outline: pass header protection key directly to UAPI

Thanks to @darkk for spotting and suggesting the fix

.github/workflows/build-if-tag.yml

@@ -0,0 +1,41 @@
+name: build-if-tag
+
+on:
+  push:
+    tags:
+      - 'v[0-9]+.[0-9]+.[0-9]+'
+
+env:
+  APP: amneziawg-go
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    name: build
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+        with:
+          ref: ${{ github.ref_name }}
+
+      - name: Login to Docker Hub
+        uses: docker/login-action@v3
+        with:
+          username: ${{ secrets.DOCKERHUB_USERNAME }}
+          password: ${{ secrets.DOCKERHUB_TOKEN }}
+
+      - name: Setup metadata
+        uses: docker/metadata-action@v5
+        id: metadata
+        with:
+          images: amneziavpn/${{ env.APP }}
+          tags: type=semver,pattern={{version}}
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+
+      - name: Build
+        uses: docker/build-push-action@v5
+        with:
+          push: true
+          tags: ${{ steps.metadata.outputs.tags }}

.gitignore

@@ -1 +1 @@
-wireguard-go
+amneziawg-go

Dockerfile

@@ -0,0 +1,24 @@
+FROM golang:1.25.12 as awg
+COPY . /awg
+WORKDIR /awg
+RUN go mod download && \
+    go mod verify && \
+    go build -ldflags '-linkmode external -extldflags "-fno-PIC -static"' -v -o /usr/bin
+
+FROM alpine:3.19 as tools
+ARG AWGTOOLS_COMMIT="v3.1.20260812"
+
+RUN apk add --no-cache git build-base linux-headers && \
+    git clone https://github.com/amnezia-vpn/amneziawg-tools.git /amneziawg-tools && \
+    cd /amneziawg-tools && git checkout ${AWGTOOLS_COMMIT} && \
+    cd src && make
+
+FROM alpine:3.19
+
+RUN apk --no-cache add iproute2 iptables bash
+COPY --from=tools /amneziawg-tools/src/wg /usr/bin/awg
+COPY --from=tools /amneziawg-tools/src/wg-quick/linux.bash /usr/bin/awg-quick
+RUN chmod +x /usr/bin/awg /usr/bin/awg-quick && \
+    ln -s /usr/bin/awg /usr/bin/wg && \
+    ln -s /usr/bin/awg-quick /usr/bin/wg-quick
+COPY --from=awg /usr/bin/amneziawg-go /usr/bin/amneziawg-go

LICENSE

@@ -1,3 +1,5 @@
+Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
+
 Permission is hereby granted, free of charge, to any person obtaining a copy of
 this software and associated documentation files (the "Software"), to deal in
 the Software without restriction, including without limitation the rights to

Makefile

@@ -9,23 +9,23 @@ MAKEFLAGS += --no-print-directory
 
 generate-version-and-build:
 	@export GIT_CEILING_DIRECTORIES="$(realpath $(CURDIR)/..)" && \
-	tag="$$(git describe --dirty 2>/dev/null)" && \
+	tag="$$(git describe --tags --dirty 2>/dev/null)" && \
 	ver="$$(printf 'package main\n\nconst Version = "%s"\n' "$$tag")" && \
 	[ "$$(cat version.go 2>/dev/null)" != "$$ver" ] && \
 	echo "$$ver" > version.go && \
 	git update-index --assume-unchanged version.go || true
-	@$(MAKE) wireguard-go
+	@$(MAKE) amneziawg-go
 
-wireguard-go: $(wildcard *.go) $(wildcard */*.go)
+amneziawg-go: $(wildcard *.go) $(wildcard */*.go)
 	go build -v -o "$@"
 
-install: wireguard-go
-	@install -v -d "$(DESTDIR)$(BINDIR)" && install -v -m 0755 "$<" "$(DESTDIR)$(BINDIR)/wireguard-go"
+install: amneziawg-go
+	@install -v -d "$(DESTDIR)$(BINDIR)" && install -v -m 0755 "$<" "$(DESTDIR)$(BINDIR)/amneziawg-go"
 
 test:
 	go test ./...
 
 clean:
-	rm -f wireguard-go
+	rm -f amneziawg-go
 
 .PHONY: all clean test install generate-version-and-build

README.md

@@ -1,24 +1,27 @@
-# Go Implementation of [WireGuard](https://www.wireguard.com/)
+# Go Implementation of AmneziaWG
 
-This is an implementation of WireGuard in Go.
+AmneziaWG is a contemporary version of the WireGuard protocol. It's a fork of WireGuard-Go and offers protection against detection by Deep Packet Inspection (DPI) systems. At the same time, it retains the simplified architecture and high performance of the original.
+
+The precursor, WireGuard, is known for its efficiency but had issues with detection due to its distinctive packet signatures.
+AmneziaWG addresses this problem by employing advanced obfuscation methods, allowing its traffic to blend seamlessly with regular internet traffic.
+As a result, AmneziaWG maintains high performance while adding an extra layer of stealth, making it a superb choice for those seeking a fast and discreet VPN connection.
 
 ## Usage
 
-Most Linux kernel WireGuard users are used to adding an interface with `ip link add wg0 type wireguard`. With wireguard-go, instead simply run:
+Simply run:
 
 ```
-$ wireguard-go wg0
+$ amneziawg-go wg0
 ```
 
-This will create an interface and fork into the background. To remove the interface, use the usual `ip link del wg0`, or if your system does not support removing interfaces directly, you may instead remove the control socket via `rm -f /var/run/wireguard/wg0.sock`, which will result in wireguard-go shutting down.
+This will create an interface and fork into the background. To remove the interface, use the usual `ip link del wg0`, or if your system does not support removing interfaces directly, you may instead remove the control socket via `rm -f /var/run/amneziawg/wg0.sock`, which will result in amneziawg-go shutting down.
 
-To run wireguard-go without forking to the background, pass `-f` or `--foreground`:
+To run amneziawg-go without forking to the background, pass `-f` or `--foreground`:
 
 ```
-$ wireguard-go -f wg0
+$ amneziawg-go -f wg0
 ```
-
-When an interface is running, you may use [`wg(8)`](https://git.zx2c4.com/wireguard-tools/about/src/man/wg.8) to configure it, as well as the usual `ip(8)` and `ifconfig(8)` commands.
+When an interface is running, you may use [`amneziawg-tools `](https://github.com/amnezia-vpn/amneziawg-tools) to configure it, as well as the usual `ip(8)` and `ifconfig(8)` commands.
 
 To run with more logging you may set the environment variable `LOG_LEVEL=debug`.
 
@@ -26,52 +29,135 @@ To run with more logging you may set the environment variable `LOG_LEVEL=debug`.
 
 ### Linux
 
-This will run on Linux; however you should instead use the kernel module, which is faster and better integrated into the OS. See the [installation page](https://www.wireguard.com/install/) for instructions.
+This will run on Linux; you should run amnezia-wg instead of using default linux kernel module.
 
 ### macOS
 
 This runs on macOS using the utun driver. It does not yet support sticky sockets, and won't support fwmarks because of Darwin limitations. Since the utun driver cannot have arbitrary interface names, you must either use `utun[0-9]+` for an explicit interface name or `utun` to have the kernel select one for you. If you choose `utun` as the interface name, and the environment variable `WG_TUN_NAME_FILE` is defined, then the actual name of the interface chosen by the kernel is written to the file specified by that variable.
+This runs on MacOS, you should use it from [amneziawg-apple](https://github.com/amnezia-vpn/amneziawg-apple)
 
 ### Windows
 
-This runs on Windows, but you should instead use it from the more [fully featured Windows app](https://git.zx2c4.com/wireguard-windows/about/), which uses this as a module.
+This runs on Windows, you should use it from [amneziawg-windows](https://github.com/amnezia-vpn/amneziawg-windows), which uses this as a module.
 
-### FreeBSD
-
-This will run on FreeBSD. It does not yet support sticky sockets. Fwmark is mapped to `SO_USER_COOKIE`.
-
-### OpenBSD
-
-This will run on OpenBSD. It does not yet support sticky sockets. Fwmark is mapped to `SO_RTABLE`. Since the tun driver cannot have arbitrary interface names, you must either use `tun[0-9]+` for an explicit interface name or `tun` to have the program select one for you. If you choose `tun` as the interface name, and the environment variable `WG_TUN_NAME_FILE` is defined, then the actual name of the interface chosen by the kernel is written to the file specified by that variable.
 
 ## Building
 
 This requires an installation of the latest version of [Go](https://go.dev/).
 
 ```
-$ git clone https://git.zx2c4.com/wireguard-go
-$ cd wireguard-go
+$ git clone https://github.com/amnezia-vpn/amneziawg-go
+$ cd amneziawg-go
 $ make
 ```
 
-## License
+## Configuration
 
-    Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
-    
-    Permission is hereby granted, free of charge, to any person obtaining a copy of
-    this software and associated documentation files (the "Software"), to deal in
-    the Software without restriction, including without limitation the rights to
-    use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
-    of the Software, and to permit persons to whom the Software is furnished to do
-    so, subject to the following conditions:
-    
-    The above copyright notice and this permission notice shall be included in all
-    copies or substantial portions of the Software.
-    
-    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-    IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-    FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-    AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-    LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-    OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
-    SOFTWARE.
+### Data types and definitions
+
+`client-side` means the param is not required to be the same on both server and client, while  
+`server-side` means this is mandatory the values are the same on server and on client  
+
+`range,x`, where x is the underlying type of left and right
+* Format: "a-b", or "a", or "(off)"
+* Example: PersistentKeepalive = 22-30
+
+> [!NOTE]
+> If there is no value specified (for any param), AWG treats it as 0
+
+### Header protection [AWG 3+]
+
+Header protection is the mechanism of protecting low-entropy values of packets' headers. The idea is to apply fast encryption to the specific fields which WireGuard does use for authentication and its own encryption. The cipher uses `S1-S4` crypto padding as nonce for each incoming packet.
+
+```
+[Device]
++ HeaderProtectionKey: key,string - server-side # the key to be used in header protection
+```
+
+> [!TIP]
+> Use `awg genkey` to generate header protection key
+
+> [!IMPORTANT]
+> Header protection requires `S1-S4` value to be 12 at least
+
+### Content padding [AWG 3+]
+
+```
+[Device]
++ ContentPaddingAddition: uint32,range - client-side # the range to be used as a custom padding
+```
+
+> [!TIP]
+> It's important to specify content padding on both sides. However, this is not strictly required and could be omitted.
+
+### Timings [AWG 3+]
+
+This param could be used to customize default Wireguard's timings
+
+```
+[Device]
++ RekeyAfterTime       = "uint32,range - client-side - seconds" # time, after which client tries to handshake
++ RekeyTimeout         = "uint32,range - client-side - seconds" # timeout, after which handshake is repeated
++ RejectAfterTime      = "uint32,range - client-side - seconds" # time, after which client forces handshake, and declines all incoming data
++ KeepaliveTimeout     = "uint32,range - client-side - seconds" # time from last data sending, after which keepalive is sent
++ MaxHandshakeAttempts = "uint32,range - client-side - amount"  # maximum attempts of handshake repetition
+
+[Peer]
+M PersistentKeepalive  = "uint32,range - client-side - seconds" # interval of persistent keepalive
+```
+
+### Junk packets
+
+The amount of junk packets specified in `Jc` with a random size between `Jmin` and `Jmax` would be generated and sent prior every handshake
+
+- `Jc: int`, recommended range is 4-12
+- `Jmin: int` <= `Jmax:int`
+
+> [!TIP]
+> Junk packets do not carry any actual data, so there is no need to specify it on both sides. General recommendation is to use it on the client side only
+
+> [!IMPORTANT]
+> If Jmax >= system MTU (not the one specified in AWG), then the system can fracture this packet into fragments, which looks suspicious from the censor side
+
+### Message paddings
+
+- `S1: int` - padding of handshake initial message
+- `S2: int` - padding of handshake response message
+- `S3: int` - padding of handshake cookie message
+- `S4: int` - padding of transport messages
+
+### Message headers
+
+Every message in wireguard has `uint32` type at the beginning of the packet. This field could be controlled by specifying the params below:
+
+- `H1: string` - header range of handshake initial message
+- `H2: string` - header range of handshake response message
+- `H3: string` - header range of handshake cookie message
+- `H4: string` - header range of transport message
+
+Values could be specified as:
+- range: `x-y`, x <= y; e.g. `123-456`
+- single value `1234`
+
+### Custom signature packets
+
+These packets are being send prior to every handshake, in the same way as Junk packets do. The sending order is `I1`, `I2`, `I3`, `I4`, `I5`. If there is no value specified, the packet is skipped.
+
+- `I1: string`
+- `I2: string`
+- `I3: string`
+- `I4: string`
+- `I5: string`
+
+Value is a sequence of tags specified below:
+- `<b 0x[seq]>` - static bytes tag. Dumps `[seq]` as-is to the packet. `[seq]` is hex-encoded sequence which represents bytes sequence (2 hex numbers per byte) and is always even-sized
+- `<r [size]>` - random bytes tag. Dumps `[size]` amount of randomly-generated bytes to the packet
+- `<rd [size]>` - random digits tag. Dumps `[size]` amount of randomly-generated bytes from `[0-9]` set to the packet
+- `<rc [size]>` - random chars tag. Dumps `[size]` amount of randomly-generated bytes from `[a-zA-Z] set to the packet
+- `<t>` - timestamp tag. Dumps 4-bytes long current system time in UNIX format
+
+> [!TIP]
+> Custom signature packets does not carry any actual data, so there is no need to specify it on both sides. General recommendation is to use it on the client side only
+
+> [!IMPORTANT]
+> If the final size of any packet exceeds system MTU, it would be fractured into fragments, which looks suspicious

conn/bind_std.go

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package conn
@@ -8,6 +8,7 @@ package conn
 import (
 	"context"
 	"errors"
+	"fmt"
 	"net"
 	"net/netip"
 	"runtime"
@@ -29,16 +30,19 @@ var (
 // methods for sending and receiving multiple datagrams per-syscall. See the
 // proposal in https://github.com/golang/go/issues/45886#issuecomment-1218301564.
 type StdNetBind struct {
-	mu     sync.Mutex // protects all fields except as specified
-	ipv4   *net.UDPConn
-	ipv6   *net.UDPConn
-	ipv4PC *ipv4.PacketConn // will be nil on non-Linux
-	ipv6PC *ipv6.PacketConn // will be nil on non-Linux
+	mu            sync.Mutex // protects all fields except as specified
+	ipv4          *net.UDPConn
+	ipv6          *net.UDPConn
+	ipv4PC        *ipv4.PacketConn // will be nil on non-Linux
+	ipv6PC        *ipv6.PacketConn // will be nil on non-Linux
+	ipv4TxOffload bool
+	ipv4RxOffload bool
+	ipv6TxOffload bool
+	ipv6RxOffload bool
 
-	// these three fields are not guarded by mu
-	udpAddrPool  sync.Pool
-	ipv4MsgsPool sync.Pool
-	ipv6MsgsPool sync.Pool
+	// these two fields are not guarded by mu
+	udpAddrPool sync.Pool
+	msgsPool    sync.Pool
 
 	blackhole4 bool
 	blackhole6 bool
@@ -54,23 +58,14 @@ func NewStdNetBind() Bind {
 			},
 		},
 
-		ipv4MsgsPool: sync.Pool{
-			New: func() any {
-				msgs := make([]ipv4.Message, IdealBatchSize)
-				for i := range msgs {
-					msgs[i].Buffers = make(net.Buffers, 1)
-					msgs[i].OOB = make([]byte, srcControlSize)
-				}
-				return &msgs
-			},
-		},
-
-		ipv6MsgsPool: sync.Pool{
+		msgsPool: sync.Pool{
 			New: func() any {
+				// ipv6.Message and ipv4.Message are interchangeable as they are
+				// both aliases for x/net/internal/socket.Message.
 				msgs := make([]ipv6.Message, IdealBatchSize)
 				for i := range msgs {
 					msgs[i].Buffers = make(net.Buffers, 1)
-					msgs[i].OOB = make([]byte, srcControlSize)
+					msgs[i].OOB = make([]byte, 0, stickyControlSize+gsoControlSize)
 				}
 				return &msgs
 			},
@@ -113,7 +108,7 @@ func (e *StdNetEndpoint) DstIP() netip.Addr {
 	return e.AddrPort.Addr()
 }
 
-// See sticky_default,linux, etc for implementations of SrcIP and SrcIfidx.
+// See control_default,linux, etc for implementations of SrcIP and SrcIfidx.
 
 func (e *StdNetEndpoint) DstToBytes() []byte {
 	b, _ := e.AddrPort.MarshalBinary()
@@ -179,19 +174,21 @@ again:
 	}
 	var fns []ReceiveFunc
 	if v4conn != nil {
-		if runtime.GOOS == "linux" {
+		s.ipv4TxOffload, s.ipv4RxOffload = supportsUDPOffload(v4conn)
+		if runtime.GOOS == "linux" || runtime.GOOS == "android" {
 			v4pc = ipv4.NewPacketConn(v4conn)
 			s.ipv4PC = v4pc
 		}
-		fns = append(fns, s.makeReceiveIPv4(v4pc, v4conn))
+		fns = append(fns, s.makeReceiveIPv4(v4pc, v4conn, s.ipv4RxOffload))
 		s.ipv4 = v4conn
 	}
 	if v6conn != nil {
-		if runtime.GOOS == "linux" {
+		s.ipv6TxOffload, s.ipv6RxOffload = supportsUDPOffload(v6conn)
+		if runtime.GOOS == "linux" || runtime.GOOS == "android" {
 			v6pc = ipv6.NewPacketConn(v6conn)
 			s.ipv6PC = v6pc
 		}
-		fns = append(fns, s.makeReceiveIPv6(v6pc, v6conn))
+		fns = append(fns, s.makeReceiveIPv6(v6pc, v6conn, s.ipv6RxOffload))
 		s.ipv6 = v6conn
 	}
 	if len(fns) == 0 {
@@ -201,76 +198,101 @@ again:
 	return fns, uint16(port), nil
 }
 
-func (s *StdNetBind) makeReceiveIPv4(pc *ipv4.PacketConn, conn *net.UDPConn) ReceiveFunc {
-	return func(bufs [][]byte, sizes []int, eps []Endpoint) (n int, err error) {
-		msgs := s.ipv4MsgsPool.Get().(*[]ipv4.Message)
-		defer s.ipv4MsgsPool.Put(msgs)
-		for i := range bufs {
-			(*msgs)[i].Buffers[0] = bufs[i]
-		}
-		var numMsgs int
-		if runtime.GOOS == "linux" {
-			numMsgs, err = pc.ReadBatch(*msgs, 0)
+func (s *StdNetBind) putMessages(msgs *[]ipv6.Message) {
+	for i := range *msgs {
+		(*msgs)[i].OOB = (*msgs)[i].OOB[:0]
+		(*msgs)[i] = ipv6.Message{Buffers: (*msgs)[i].Buffers, OOB: (*msgs)[i].OOB}
+	}
+	s.msgsPool.Put(msgs)
+}
+
+func (s *StdNetBind) getMessages() *[]ipv6.Message {
+	return s.msgsPool.Get().(*[]ipv6.Message)
+}
+
+var (
+	// If compilation fails here these are no longer the same underlying type.
+	_ ipv6.Message = ipv4.Message{}
+)
+
+type batchReader interface {
+	ReadBatch([]ipv6.Message, int) (int, error)
+}
+
+type batchWriter interface {
+	WriteBatch([]ipv6.Message, int) (int, error)
+}
+
+func (s *StdNetBind) receiveIP(
+	br batchReader,
+	conn *net.UDPConn,
+	rxOffload bool,
+	bufs [][]byte,
+	sizes []int,
+	eps []Endpoint,
+) (n int, err error) {
+	msgs := s.getMessages()
+	for i := range bufs {
+		(*msgs)[i].Buffers[0] = bufs[i]
+		(*msgs)[i].OOB = (*msgs)[i].OOB[:cap((*msgs)[i].OOB)]
+	}
+	defer s.putMessages(msgs)
+	var numMsgs int
+	if runtime.GOOS == "linux" || runtime.GOOS == "android" {
+		if rxOffload {
+			readAt := len(*msgs) - (IdealBatchSize / udpSegmentMaxDatagrams)
+			numMsgs, err = br.ReadBatch((*msgs)[readAt:], 0)
+			if err != nil {
+				return 0, err
+			}
+			numMsgs, err = splitCoalescedMessages(*msgs, readAt, getGSOSize)
 			if err != nil {
 				return 0, err
 			}
 		} else {
-			msg := &(*msgs)[0]
-			msg.N, msg.NN, _, msg.Addr, err = conn.ReadMsgUDP(msg.Buffers[0], msg.OOB)
+			numMsgs, err = br.ReadBatch(*msgs, 0)
 			if err != nil {
 				return 0, err
 			}
-			numMsgs = 1
 		}
-		for i := 0; i < numMsgs; i++ {
-			msg := &(*msgs)[i]
-			sizes[i] = msg.N
-			addrPort := msg.Addr.(*net.UDPAddr).AddrPort()
-			ep := &StdNetEndpoint{AddrPort: addrPort} // TODO: remove allocation
-			getSrcFromControl(msg.OOB[:msg.NN], ep)
-			eps[i] = ep
+	} else {
+		msg := &(*msgs)[0]
+		msg.N, msg.NN, _, msg.Addr, err = conn.ReadMsgUDP(msg.Buffers[0], msg.OOB)
+		if err != nil {
+			return 0, err
 		}
-		return numMsgs, nil
+		numMsgs = 1
+	}
+	for i := 0; i < numMsgs; i++ {
+		msg := &(*msgs)[i]
+		sizes[i] = msg.N
+		if sizes[i] == 0 {
+			continue
+		}
+		addrPort := msg.Addr.(*net.UDPAddr).AddrPort()
+		ep := &StdNetEndpoint{AddrPort: addrPort} // TODO: remove allocation
+		getSrcFromControl(msg.OOB[:msg.NN], ep)
+		eps[i] = ep
+	}
+	return numMsgs, nil
+}
+
+func (s *StdNetBind) makeReceiveIPv4(pc *ipv4.PacketConn, conn *net.UDPConn, rxOffload bool) ReceiveFunc {
+	return func(bufs [][]byte, sizes []int, eps []Endpoint) (n int, err error) {
+		return s.receiveIP(pc, conn, rxOffload, bufs, sizes, eps)
 	}
 }
 
-func (s *StdNetBind) makeReceiveIPv6(pc *ipv6.PacketConn, conn *net.UDPConn) ReceiveFunc {
+func (s *StdNetBind) makeReceiveIPv6(pc *ipv6.PacketConn, conn *net.UDPConn, rxOffload bool) ReceiveFunc {
 	return func(bufs [][]byte, sizes []int, eps []Endpoint) (n int, err error) {
-		msgs := s.ipv6MsgsPool.Get().(*[]ipv6.Message)
-		defer s.ipv6MsgsPool.Put(msgs)
-		for i := range bufs {
-			(*msgs)[i].Buffers[0] = bufs[i]
-		}
-		var numMsgs int
-		if runtime.GOOS == "linux" {
-			numMsgs, err = pc.ReadBatch(*msgs, 0)
-			if err != nil {
-				return 0, err
-			}
-		} else {
-			msg := &(*msgs)[0]
-			msg.N, msg.NN, _, msg.Addr, err = conn.ReadMsgUDP(msg.Buffers[0], msg.OOB)
-			if err != nil {
-				return 0, err
-			}
-			numMsgs = 1
-		}
-		for i := 0; i < numMsgs; i++ {
-			msg := &(*msgs)[i]
-			sizes[i] = msg.N
-			addrPort := msg.Addr.(*net.UDPAddr).AddrPort()
-			ep := &StdNetEndpoint{AddrPort: addrPort} // TODO: remove allocation
-			getSrcFromControl(msg.OOB[:msg.NN], ep)
-			eps[i] = ep
-		}
-		return numMsgs, nil
+		return s.receiveIP(pc, conn, rxOffload, bufs, sizes, eps)
 	}
 }
 
 // TODO: When all Binds handle IdealBatchSize, remove this dynamic function and
 // rename the IdealBatchSize constant to BatchSize.
 func (s *StdNetBind) BatchSize() int {
-	if runtime.GOOS == "linux" {
+	if runtime.GOOS == "linux" || runtime.GOOS == "android" {
 		return IdealBatchSize
 	}
 	return 1
@@ -293,28 +315,42 @@ func (s *StdNetBind) Close() error {
 	}
 	s.blackhole4 = false
 	s.blackhole6 = false
+	s.ipv4TxOffload = false
+	s.ipv4RxOffload = false
+	s.ipv6TxOffload = false
+	s.ipv6RxOffload = false
 	if err1 != nil {
 		return err1
 	}
 	return err2
 }
 
+type ErrUDPGSODisabled struct {
+	onLaddr  string
+	RetryErr error
+}
+
+func (e ErrUDPGSODisabled) Error() string {
+	return fmt.Sprintf("disabled UDP GSO on %s, NIC(s) may not support checksum offload or peer MTU with protocol headers is greater than path MTU", e.onLaddr)
+}
+
+func (e ErrUDPGSODisabled) Unwrap() error {
+	return e.RetryErr
+}
+
 func (s *StdNetBind) Send(bufs [][]byte, endpoint Endpoint) error {
 	s.mu.Lock()
 	blackhole := s.blackhole4
 	conn := s.ipv4
-	var (
-		pc4 *ipv4.PacketConn
-		pc6 *ipv6.PacketConn
-	)
+	offload := s.ipv4TxOffload
+	br := batchWriter(s.ipv4PC)
 	is6 := false
 	if endpoint.DstIP().Is6() {
 		blackhole = s.blackhole6
 		conn = s.ipv6
-		pc6 = s.ipv6PC
+		br = s.ipv6PC
 		is6 = true
-	} else {
-		pc4 = s.ipv4PC
+		offload = s.ipv6TxOffload
 	}
 	s.mu.Unlock()
 
@@ -324,85 +360,185 @@ func (s *StdNetBind) Send(bufs [][]byte, endpoint Endpoint) error {
 	if conn == nil {
 		return syscall.EAFNOSUPPORT
 	}
+
+	msgs := s.getMessages()
+	defer s.putMessages(msgs)
+	ua := s.udpAddrPool.Get().(*net.UDPAddr)
+	defer s.udpAddrPool.Put(ua)
 	if is6 {
-		return s.send6(conn, pc6, endpoint, bufs)
+		as16 := endpoint.DstIP().As16()
+		copy(ua.IP, as16[:])
+		ua.IP = ua.IP[:16]
 	} else {
-		return s.send4(conn, pc4, endpoint, bufs)
+		as4 := endpoint.DstIP().As4()
+		copy(ua.IP, as4[:])
+		ua.IP = ua.IP[:4]
 	}
+	ua.Port = int(endpoint.(*StdNetEndpoint).Port())
+	var (
+		retried bool
+		err     error
+	)
+retry:
+	if offload {
+		n := coalesceMessages(ua, endpoint.(*StdNetEndpoint), bufs, *msgs, setGSOSize)
+		err = s.send(conn, br, (*msgs)[:n])
+		if err != nil && offload && errShouldDisableUDPGSO(err) {
+			offload = false
+			s.mu.Lock()
+			if is6 {
+				s.ipv6TxOffload = false
+			} else {
+				s.ipv4TxOffload = false
+			}
+			s.mu.Unlock()
+			retried = true
+			goto retry
+		}
+	} else {
+		for i := range bufs {
+			(*msgs)[i].Addr = ua
+			(*msgs)[i].Buffers[0] = bufs[i]
+			setSrcControl(&(*msgs)[i].OOB, endpoint.(*StdNetEndpoint))
+		}
+		err = s.send(conn, br, (*msgs)[:len(bufs)])
+	}
+	if retried {
+		return ErrUDPGSODisabled{onLaddr: conn.LocalAddr().String(), RetryErr: err}
+	}
+	return err
 }
 
-func (s *StdNetBind) send4(conn *net.UDPConn, pc *ipv4.PacketConn, ep Endpoint, bufs [][]byte) error {
-	ua := s.udpAddrPool.Get().(*net.UDPAddr)
-	as4 := ep.DstIP().As4()
-	copy(ua.IP, as4[:])
-	ua.IP = ua.IP[:4]
-	ua.Port = int(ep.(*StdNetEndpoint).Port())
-	msgs := s.ipv4MsgsPool.Get().(*[]ipv4.Message)
-	for i, buf := range bufs {
-		(*msgs)[i].Buffers[0] = buf
-		(*msgs)[i].Addr = ua
-		setSrcControl(&(*msgs)[i].OOB, ep.(*StdNetEndpoint))
-	}
+func (s *StdNetBind) send(conn *net.UDPConn, pc batchWriter, msgs []ipv6.Message) error {
 	var (
 		n     int
 		err   error
 		start int
 	)
-	if runtime.GOOS == "linux" {
+	if runtime.GOOS == "linux" || runtime.GOOS == "android" {
 		for {
-			n, err = pc.WriteBatch((*msgs)[start:len(bufs)], 0)
-			if err != nil || n == len((*msgs)[start:len(bufs)]) {
+			n, err = pc.WriteBatch(msgs[start:], 0)
+			if err != nil || n == len(msgs[start:]) {
 				break
 			}
 			start += n
 		}
 	} else {
-		for i, buf := range bufs {
-			_, _, err = conn.WriteMsgUDP(buf, (*msgs)[i].OOB, ua)
+		for _, msg := range msgs {
+			_, _, err = conn.WriteMsgUDP(msg.Buffers[0], msg.OOB, msg.Addr.(*net.UDPAddr))
 			if err != nil {
 				break
 			}
 		}
 	}
-	s.udpAddrPool.Put(ua)
-	s.ipv4MsgsPool.Put(msgs)
 	return err
 }
 
-func (s *StdNetBind) send6(conn *net.UDPConn, pc *ipv6.PacketConn, ep Endpoint, bufs [][]byte) error {
-	ua := s.udpAddrPool.Get().(*net.UDPAddr)
-	as16 := ep.DstIP().As16()
-	copy(ua.IP, as16[:])
-	ua.IP = ua.IP[:16]
-	ua.Port = int(ep.(*StdNetEndpoint).Port())
-	msgs := s.ipv6MsgsPool.Get().(*[]ipv6.Message)
-	for i, buf := range bufs {
-		(*msgs)[i].Buffers[0] = buf
-		(*msgs)[i].Addr = ua
-		setSrcControl(&(*msgs)[i].OOB, ep.(*StdNetEndpoint))
-	}
+const (
+	// Exceeding these values results in EMSGSIZE. They account for layer3 and
+	// layer4 headers. IPv6 does not need to account for itself as the payload
+	// length field is self excluding.
+	maxIPv4PayloadLen = 1<<16 - 1 - 20 - 8
+	maxIPv6PayloadLen = 1<<16 - 1 - 8
+
+	// This is a hard limit imposed by the kernel.
+	udpSegmentMaxDatagrams = 64
+)
+
+type setGSOFunc func(control *[]byte, gsoSize uint16)
+
+func coalesceMessages(addr *net.UDPAddr, ep *StdNetEndpoint, bufs [][]byte, msgs []ipv6.Message, setGSO setGSOFunc) int {
 	var (
-		n     int
-		err   error
-		start int
+		base     = -1 // index of msg we are currently coalescing into
+		gsoSize  int  // segmentation size of msgs[base]
+		dgramCnt int  // number of dgrams coalesced into msgs[base]
+		endBatch bool // tracking flag to start a new batch on next iteration of bufs
 	)
-	if runtime.GOOS == "linux" {
-		for {
-			n, err = pc.WriteBatch((*msgs)[start:len(bufs)], 0)
-			if err != nil || n == len((*msgs)[start:len(bufs)]) {
-				break
+	maxPayloadLen := maxIPv4PayloadLen
+	if ep.DstIP().Is6() {
+		maxPayloadLen = maxIPv6PayloadLen
+	}
+	for i, buf := range bufs {
+		if i > 0 {
+			msgLen := len(buf)
+			baseLenBefore := len(msgs[base].Buffers[0])
+			freeBaseCap := cap(msgs[base].Buffers[0]) - baseLenBefore
+			if msgLen+baseLenBefore <= maxPayloadLen &&
+				msgLen <= gsoSize &&
+				msgLen <= freeBaseCap &&
+				dgramCnt < udpSegmentMaxDatagrams &&
+				!endBatch {
+				msgs[base].Buffers[0] = append(msgs[base].Buffers[0], buf...)
+				if i == len(bufs)-1 {
+					setGSO(&msgs[base].OOB, uint16(gsoSize))
+				}
+				dgramCnt++
+				if msgLen < gsoSize {
+					// A smaller than gsoSize packet on the tail is legal, but
+					// it must end the batch.
+					endBatch = true
+				}
+				continue
 			}
-			start += n
 		}
-	} else {
-		for i, buf := range bufs {
-			_, _, err = conn.WriteMsgUDP(buf, (*msgs)[i].OOB, ua)
-			if err != nil {
-				break
+		if dgramCnt > 1 {
+			setGSO(&msgs[base].OOB, uint16(gsoSize))
+		}
+		// Reset prior to incrementing base since we are preparing to start a
+		// new potential batch.
+		endBatch = false
+		base++
+		gsoSize = len(buf)
+		setSrcControl(&msgs[base].OOB, ep)
+		msgs[base].Buffers[0] = buf
+		msgs[base].Addr = addr
+		dgramCnt = 1
+	}
+	return base + 1
+}
+
+type getGSOFunc func(control []byte) (int, error)
+
+func splitCoalescedMessages(msgs []ipv6.Message, firstMsgAt int, getGSO getGSOFunc) (n int, err error) {
+	for i := firstMsgAt; i < len(msgs); i++ {
+		msg := &msgs[i]
+		if msg.N == 0 {
+			return n, err
+		}
+		var (
+			gsoSize    int
+			start      int
+			end        = msg.N
+			numToSplit = 1
+		)
+		gsoSize, err = getGSO(msg.OOB[:msg.NN])
+		if err != nil {
+			return n, err
+		}
+		if gsoSize > 0 {
+			numToSplit = (msg.N + gsoSize - 1) / gsoSize
+			end = gsoSize
+		}
+		for j := 0; j < numToSplit; j++ {
+			if n > i {
+				return n, errors.New("splitting coalesced packet resulted in overflow")
 			}
+			copied := copy(msgs[n].Buffers[0], msg.Buffers[0][start:end])
+			msgs[n].N = copied
+			msgs[n].Addr = msg.Addr
+			start = end
+			end += gsoSize
+			if end > msg.N {
+				end = msg.N
+			}
+			n++
+		}
+		if i != n-1 {
+			// It is legal for bytes to move within msg.Buffers[0] as a result
+			// of splitting, so we only zero the source msg len when it is not
+			// the destination of the last split operation above.
+			msg.N = 0
 		}
 	}
-	s.udpAddrPool.Put(ua)
-	s.ipv6MsgsPool.Put(msgs)
-	return err
+	return n, nil
 }

conn/bind_std_test.go

@@ -1,6 +1,12 @@
 package conn
 
-import "testing"
+import (
+	"encoding/binary"
+	"net"
+	"testing"
+
+	"golang.org/x/net/ipv6"
+)
 
 func TestStdNetBindReceiveFuncAfterClose(t *testing.T) {
 	bind := NewStdNetBind().(*StdNetBind)
@@ -20,3 +26,225 @@ func TestStdNetBindReceiveFuncAfterClose(t *testing.T) {
 		fn(bufs, sizes, eps)
 	}
 }
+
+func mockSetGSOSize(control *[]byte, gsoSize uint16) {
+	*control = (*control)[:cap(*control)]
+	binary.LittleEndian.PutUint16(*control, gsoSize)
+}
+
+func Test_coalesceMessages(t *testing.T) {
+	cases := []struct {
+		name     string
+		buffs    [][]byte
+		wantLens []int
+		wantGSO  []int
+	}{
+		{
+			name: "one message no coalesce",
+			buffs: [][]byte{
+				make([]byte, 1, 1),
+			},
+			wantLens: []int{1},
+			wantGSO:  []int{0},
+		},
+		{
+			name: "two messages equal len coalesce",
+			buffs: [][]byte{
+				make([]byte, 1, 2),
+				make([]byte, 1, 1),
+			},
+			wantLens: []int{2},
+			wantGSO:  []int{1},
+		},
+		{
+			name: "two messages unequal len coalesce",
+			buffs: [][]byte{
+				make([]byte, 2, 3),
+				make([]byte, 1, 1),
+			},
+			wantLens: []int{3},
+			wantGSO:  []int{2},
+		},
+		{
+			name: "three messages second unequal len coalesce",
+			buffs: [][]byte{
+				make([]byte, 2, 3),
+				make([]byte, 1, 1),
+				make([]byte, 2, 2),
+			},
+			wantLens: []int{3, 2},
+			wantGSO:  []int{2, 0},
+		},
+		{
+			name: "three messages limited cap coalesce",
+			buffs: [][]byte{
+				make([]byte, 2, 4),
+				make([]byte, 2, 2),
+				make([]byte, 2, 2),
+			},
+			wantLens: []int{4, 2},
+			wantGSO:  []int{2, 0},
+		},
+	}
+
+	for _, tt := range cases {
+		t.Run(tt.name, func(t *testing.T) {
+			addr := &net.UDPAddr{
+				IP:   net.ParseIP("127.0.0.1").To4(),
+				Port: 1,
+			}
+			msgs := make([]ipv6.Message, len(tt.buffs))
+			for i := range msgs {
+				msgs[i].Buffers = make([][]byte, 1)
+				msgs[i].OOB = make([]byte, 0, 2)
+			}
+			got := coalesceMessages(addr, &StdNetEndpoint{AddrPort: addr.AddrPort()}, tt.buffs, msgs, mockSetGSOSize)
+			if got != len(tt.wantLens) {
+				t.Fatalf("got len %d want: %d", got, len(tt.wantLens))
+			}
+			for i := 0; i < got; i++ {
+				if msgs[i].Addr != addr {
+					t.Errorf("msgs[%d].Addr != passed addr", i)
+				}
+				gotLen := len(msgs[i].Buffers[0])
+				if gotLen != tt.wantLens[i] {
+					t.Errorf("len(msgs[%d].Buffers[0]) %d != %d", i, gotLen, tt.wantLens[i])
+				}
+				gotGSO, err := mockGetGSOSize(msgs[i].OOB)
+				if err != nil {
+					t.Fatalf("msgs[%d] getGSOSize err: %v", i, err)
+				}
+				if gotGSO != tt.wantGSO[i] {
+					t.Errorf("msgs[%d] gsoSize %d != %d", i, gotGSO, tt.wantGSO[i])
+				}
+			}
+		})
+	}
+}
+
+func mockGetGSOSize(control []byte) (int, error) {
+	if len(control) < 2 {
+		return 0, nil
+	}
+	return int(binary.LittleEndian.Uint16(control)), nil
+}
+
+func Test_splitCoalescedMessages(t *testing.T) {
+	newMsg := func(n, gso int) ipv6.Message {
+		msg := ipv6.Message{
+			Buffers: [][]byte{make([]byte, 1<<16-1)},
+			N:       n,
+			OOB:     make([]byte, 2),
+		}
+		binary.LittleEndian.PutUint16(msg.OOB, uint16(gso))
+		if gso > 0 {
+			msg.NN = 2
+		}
+		return msg
+	}
+
+	cases := []struct {
+		name        string
+		msgs        []ipv6.Message
+		firstMsgAt  int
+		wantNumEval int
+		wantMsgLens []int
+		wantErr     bool
+	}{
+		{
+			name: "second last split last empty",
+			msgs: []ipv6.Message{
+				newMsg(0, 0),
+				newMsg(0, 0),
+				newMsg(3, 1),
+				newMsg(0, 0),
+			},
+			firstMsgAt:  2,
+			wantNumEval: 3,
+			wantMsgLens: []int{1, 1, 1, 0},
+			wantErr:     false,
+		},
+		{
+			name: "second last no split last empty",
+			msgs: []ipv6.Message{
+				newMsg(0, 0),
+				newMsg(0, 0),
+				newMsg(1, 0),
+				newMsg(0, 0),
+			},
+			firstMsgAt:  2,
+			wantNumEval: 1,
+			wantMsgLens: []int{1, 0, 0, 0},
+			wantErr:     false,
+		},
+		{
+			name: "second last no split last no split",
+			msgs: []ipv6.Message{
+				newMsg(0, 0),
+				newMsg(0, 0),
+				newMsg(1, 0),
+				newMsg(1, 0),
+			},
+			firstMsgAt:  2,
+			wantNumEval: 2,
+			wantMsgLens: []int{1, 1, 0, 0},
+			wantErr:     false,
+		},
+		{
+			name: "second last no split last split",
+			msgs: []ipv6.Message{
+				newMsg(0, 0),
+				newMsg(0, 0),
+				newMsg(1, 0),
+				newMsg(3, 1),
+			},
+			firstMsgAt:  2,
+			wantNumEval: 4,
+			wantMsgLens: []int{1, 1, 1, 1},
+			wantErr:     false,
+		},
+		{
+			name: "second last split last split",
+			msgs: []ipv6.Message{
+				newMsg(0, 0),
+				newMsg(0, 0),
+				newMsg(2, 1),
+				newMsg(2, 1),
+			},
+			firstMsgAt:  2,
+			wantNumEval: 4,
+			wantMsgLens: []int{1, 1, 1, 1},
+			wantErr:     false,
+		},
+		{
+			name: "second last no split last split overflow",
+			msgs: []ipv6.Message{
+				newMsg(0, 0),
+				newMsg(0, 0),
+				newMsg(1, 0),
+				newMsg(4, 1),
+			},
+			firstMsgAt:  2,
+			wantNumEval: 4,
+			wantMsgLens: []int{1, 1, 1, 1},
+			wantErr:     true,
+		},
+	}
+
+	for _, tt := range cases {
+		t.Run(tt.name, func(t *testing.T) {
+			got, err := splitCoalescedMessages(tt.msgs, 2, mockGetGSOSize)
+			if err != nil && !tt.wantErr {
+				t.Fatalf("err: %v", err)
+			}
+			if got != tt.wantNumEval {
+				t.Fatalf("got to eval: %d want: %d", got, tt.wantNumEval)
+			}
+			for i, msg := range tt.msgs {
+				if msg.N != tt.wantMsgLens[i] {
+					t.Fatalf("msg[%d].N: %d want: %d", i, msg.N, tt.wantMsgLens[i])
+				}
+			}
+		})
+	}
+}

conn/bind_windows.go

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package conn
@@ -17,7 +17,7 @@ import (
 
 	"golang.org/x/sys/windows"
 
-	"golang.zx2c4.com/wireguard/conn/winrio"
+	"github.com/amnezia-vpn/amneziawg-go/v3/conn/winrio"
 )
 
 const (
@@ -582,6 +582,24 @@ func (bind *WinRingBind) BindSocketToInterface6(interfaceIndex uint32, blackhole
 	return nil
 }
 
+func (bind *WinRingBind) PeekLookAtSocketFd4() (fd int, err error) {
+	bind.mu.RLock()
+	defer bind.mu.RUnlock()
+	if bind.isOpen.Load() != 1 {
+		return -1, net.ErrClosed
+	}
+	return int(bind.v4.sock), nil
+}
+
+func (bind *WinRingBind) PeekLookAtSocketFd6() (fd int, err error) {
+	bind.mu.RLock()
+	defer bind.mu.RUnlock()
+	if bind.isOpen.Load() != 1 {
+		return -1, net.ErrClosed
+	}
+	return int(bind.v6.sock), nil
+}
+
 func bindSocketToInterface4(handle windows.Handle, interfaceIndex uint32) error {
 	const IP_UNICAST_IF = 31
 	/* MSDN says for IPv4 this needs to be in net byte order, so that it's like an IP address with leading zeros. */

conn/bindtest/bindtest.go

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package bindtest
@@ -12,7 +12,7 @@ import (
 	"net/netip"
 	"os"
 
-	"golang.zx2c4.com/wireguard/conn"
+	"github.com/amnezia-vpn/amneziawg-go/v3/conn"
 )
 
 type ChannelBind struct {

conn/boundif.go

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package conn

conn/conn.go

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 // Package conn implements WireGuard's network connections.

conn/conn_test.go

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package conn

conn/controlfns.go

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package conn

conn/controlfns_linux.go

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package conn
@@ -13,6 +13,35 @@ import (
 	"golang.org/x/sys/unix"
 )
 
+// Taken from go/src/internal/syscall/unix/kernel_version_linux.go
+func kernelVersion() (major, minor int) {
+	var uname unix.Utsname
+	if err := unix.Uname(&uname); err != nil {
+		return
+	}
+
+	var (
+		values    [2]int
+		value, vi int
+	)
+	for _, c := range uname.Release {
+		if '0' <= c && c <= '9' {
+			value = (value * 10) + int(c-'0')
+		} else {
+			// Note that we're assuming N.N.N here.
+			// If we see anything else, we are likely to mis-parse it.
+			values[vi] = value
+			vi++
+			if vi >= len(values) {
+				break
+			}
+			value = 0
+		}
+	}
+
+	return values[0], values[1]
+}
+
 func init() {
 	controlFns = append(controlFns,
 
@@ -57,5 +86,24 @@ func init() {
 			}
 			return err
 		},
+
+		// Attempt to enable UDP_GRO
+		func(network, address string, c syscall.RawConn) error {
+			// Kernels below 5.12 are missing 98184612aca0 ("net:
+			// udp: Add support for getsockopt(..., ..., UDP_GRO,
+			// ..., ...);"), which means we can't read this back
+			// later. We could pipe the return value through to
+			// the rest of the code, but UDP_GRO is kind of buggy
+			// anyway, so just gate this here.
+			major, minor := kernelVersion()
+			if major < 5 || (major == 5 && minor < 12) {
+				return nil
+			}
+
+			c.Control(func(fd uintptr) {
+				_ = unix.SetsockoptInt(int(fd), unix.IPPROTO_UDP, unix.UDP_GRO, 1)
+			})
+			return nil
+		},
 	)
 }

conn/controlfns_unix.go

@@ -2,7 +2,7 @@
 
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package conn

conn/controlfns_windows.go

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package conn

conn/default.go

@@ -2,7 +2,7 @@
 
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package conn

conn/errors_default.go

@@ -0,0 +1,12 @@
+//go:build !linux
+
+/* SPDX-License-Identifier: MIT
+ *
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
+ */
+
+package conn
+
+func errShouldDisableUDPGSO(_ error) bool {
+	return false
+}

conn/errors_linux.go

@@ -0,0 +1,28 @@
+/* SPDX-License-Identifier: MIT
+ *
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
+ */
+
+package conn
+
+import (
+	"errors"
+	"os"
+
+	"golang.org/x/sys/unix"
+)
+
+func errShouldDisableUDPGSO(err error) bool {
+	var serr *os.SyscallError
+	if errors.As(err, &serr) {
+		// EIO is returned by udp_send_skb() if the device driver does not have
+		// tx checksumming enabled, which is a hard requirement of UDP_SEGMENT.
+		// See:
+		// https://git.kernel.org/pub/scm/docs/man-pages/man-pages.git/tree/man7/udp.7?id=806eabd74910447f21005160e90957bde4db0183#n228
+		// https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/net/ipv4/udp.c?h=v6.2&id=c9c3395d5e3dcc6daee66c6908354d47bf98cb0c#n942
+		// If gso_size + udp + ip headers > fragment size EINVAL is returned.
+		// It occurs when the peer mtu + wg headers is greater than path mtu.
+		return serr.Err == unix.EIO || serr.Err == unix.EINVAL
+	}
+	return false
+}

conn/features_default.go

@@ -0,0 +1,15 @@
+//go:build !linux
+// +build !linux
+
+/* SPDX-License-Identifier: MIT
+ *
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
+ */
+
+package conn
+
+import "net"
+
+func supportsUDPOffload(_ *net.UDPConn) (txOffload, rxOffload bool) {
+	return
+}

conn/features_linux.go

@@ -0,0 +1,31 @@
+/* SPDX-License-Identifier: MIT
+ *
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
+ */
+
+package conn
+
+import (
+	"net"
+
+	"golang.org/x/sys/unix"
+)
+
+func supportsUDPOffload(conn *net.UDPConn) (txOffload, rxOffload bool) {
+	rc, err := conn.SyscallConn()
+	if err != nil {
+		return
+	}
+	err = rc.Control(func(fd uintptr) {
+		_, errSyscall := unix.GetsockoptInt(int(fd), unix.IPPROTO_UDP, unix.UDP_SEGMENT)
+		txOffload = errSyscall == nil
+		// getsockopt(IPPROTO_UDP, UDP_GRO) is not supported in android
+		// use setsockopt workaround
+		errSyscall = unix.SetsockoptInt(int(fd), unix.IPPROTO_UDP, unix.UDP_GRO, 1)
+		rxOffload = errSyscall == nil
+	})
+	if err != nil {
+		return false, false
+	}
+	return txOffload, rxOffload
+}

conn/gso_default.go

@@ -0,0 +1,21 @@
+//go:build !linux
+
+/* SPDX-License-Identifier: MIT
+ *
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
+ */
+
+package conn
+
+// getGSOSize parses control for UDP_GRO and if found returns its GSO size data.
+func getGSOSize(control []byte) (int, error) {
+	return 0, nil
+}
+
+// setGSOSize sets a UDP_SEGMENT in control based on gsoSize.
+func setGSOSize(control *[]byte, gsoSize uint16) {
+}
+
+// gsoControlSize returns the recommended buffer size for pooling sticky and UDP
+// offloading control data.
+const gsoControlSize = 0

conn/gso_linux.go

@@ -0,0 +1,65 @@
+//go:build linux
+
+/* SPDX-License-Identifier: MIT
+ *
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
+ */
+
+package conn
+
+import (
+	"fmt"
+	"unsafe"
+
+	"golang.org/x/sys/unix"
+)
+
+const (
+	sizeOfGSOData = 2
+)
+
+// getGSOSize parses control for UDP_GRO and if found returns its GSO size data.
+func getGSOSize(control []byte) (int, error) {
+	var (
+		hdr  unix.Cmsghdr
+		data []byte
+		rem  = control
+		err  error
+	)
+
+	for len(rem) > unix.SizeofCmsghdr {
+		hdr, data, rem, err = unix.ParseOneSocketControlMessage(rem)
+		if err != nil {
+			return 0, fmt.Errorf("error parsing socket control message: %w", err)
+		}
+		if hdr.Level == unix.SOL_UDP && hdr.Type == unix.UDP_GRO && len(data) >= sizeOfGSOData {
+			var gso uint16
+			copy(unsafe.Slice((*byte)(unsafe.Pointer(&gso)), sizeOfGSOData), data[:sizeOfGSOData])
+			return int(gso), nil
+		}
+	}
+	return 0, nil
+}
+
+// setGSOSize sets a UDP_SEGMENT in control based on gsoSize. It leaves existing
+// data in control untouched.
+func setGSOSize(control *[]byte, gsoSize uint16) {
+	existingLen := len(*control)
+	avail := cap(*control) - existingLen
+	space := unix.CmsgSpace(sizeOfGSOData)
+	if avail < space {
+		return
+	}
+	*control = (*control)[:cap(*control)]
+	gsoControl := (*control)[existingLen:]
+	hdr := (*unix.Cmsghdr)(unsafe.Pointer(&(gsoControl)[0]))
+	hdr.Level = unix.SOL_UDP
+	hdr.Type = unix.UDP_SEGMENT
+	hdr.SetLen(unix.CmsgLen(sizeOfGSOData))
+	copy((gsoControl)[unix.CmsgLen(0):], unsafe.Slice((*byte)(unsafe.Pointer(&gsoSize)), sizeOfGSOData))
+	*control = (*control)[:existingLen+space]
+}
+
+// gsoControlSize returns the recommended buffer size for pooling UDP
+// offloading control data.
+var gsoControlSize = unix.CmsgSpace(sizeOfGSOData)

conn/mark_default.go

@@ -2,7 +2,7 @@
 
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package conn

conn/mark_unix.go

@@ -2,7 +2,7 @@
 
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package conn

conn/sticky_default.go

@@ -2,7 +2,7 @@
 
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package conn
@@ -21,8 +21,9 @@ func (e *StdNetEndpoint) SrcToString() string {
 	return ""
 }
 
-// TODO: macOS, FreeBSD and other BSDs likely do support this feature set, but
-// use alternatively named flags and need ports and require testing.
+// TODO: macOS, FreeBSD and other BSDs likely do support the sticky sockets
+// {get,set}srcControl feature set, but use alternatively named flags and need
+// ports and require testing.
 
 // getSrcFromControl parses the control for PKTINFO and if found updates ep with
 // the source information found.
@@ -34,8 +35,8 @@ func getSrcFromControl(control []byte, ep *StdNetEndpoint) {
 func setSrcControl(control *[]byte, ep *StdNetEndpoint) {
 }
 
-// srcControlSize returns the recommended buffer size for pooling sticky control
-// data.
-const srcControlSize = 0
+// stickyControlSize returns the recommended buffer size for pooling sticky
+// offloading control data.
+const stickyControlSize = 0
 
 const StdNetSupportsStickySockets = false

conn/sticky_linux.go

@@ -2,7 +2,7 @@
 
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package conn
@@ -105,6 +105,8 @@ func setSrcControl(control *[]byte, ep *StdNetEndpoint) {
 	*control = append(*control, ep.src...)
 }
 
-var srcControlSize = unix.CmsgSpace(unix.SizeofInet6Pktinfo)
+// stickyControlSize returns the recommended buffer size for pooling sticky
+// offloading control data.
+var stickyControlSize = unix.CmsgSpace(unix.SizeofInet6Pktinfo)
 
 const StdNetSupportsStickySockets = true

conn/sticky_linux_test.go

@@ -2,7 +2,7 @@
 
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package conn
@@ -60,7 +60,7 @@ func Test_setSrcControl(t *testing.T) {
 		}
 		setSrc(ep, netip.MustParseAddr("127.0.0.1"), 5)
 
-		control := make([]byte, srcControlSize)
+		control := make([]byte, stickyControlSize)
 
 		setSrcControl(&control, ep)
 
@@ -89,7 +89,7 @@ func Test_setSrcControl(t *testing.T) {
 		}
 		setSrc(ep, netip.MustParseAddr("::1"), 5)
 
-		control := make([]byte, srcControlSize)
+		control := make([]byte, stickyControlSize)
 
 		setSrcControl(&control, ep)
 
@@ -113,7 +113,7 @@ func Test_setSrcControl(t *testing.T) {
 	})
 
 	t.Run("ClearOnNoSrc", func(t *testing.T) {
-		control := make([]byte, unix.CmsgLen(0))
+		control := make([]byte, stickyControlSize)
 		hdr := (*unix.Cmsghdr)(unsafe.Pointer(&control[0]))
 		hdr.Level = 1
 		hdr.Type = 2
@@ -129,7 +129,7 @@ func Test_setSrcControl(t *testing.T) {
 
 func Test_getSrcFromControl(t *testing.T) {
 	t.Run("IPv4", func(t *testing.T) {
-		control := make([]byte, unix.CmsgSpace(unix.SizeofInet4Pktinfo))
+		control := make([]byte, stickyControlSize)
 		hdr := (*unix.Cmsghdr)(unsafe.Pointer(&control[0]))
 		hdr.Level = unix.IPPROTO_IP
 		hdr.Type = unix.IP_PKTINFO
@@ -149,7 +149,7 @@ func Test_getSrcFromControl(t *testing.T) {
 		}
 	})
 	t.Run("IPv6", func(t *testing.T) {
-		control := make([]byte, unix.CmsgSpace(unix.SizeofInet6Pktinfo))
+		control := make([]byte, stickyControlSize)
 		hdr := (*unix.Cmsghdr)(unsafe.Pointer(&control[0]))
 		hdr.Level = unix.IPPROTO_IPV6
 		hdr.Type = unix.IPV6_PKTINFO

conn/winrio/rio_windows.go

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package winrio

device/allowedips.go

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package device
@@ -223,6 +223,60 @@ func (table *AllowedIPs) EntriesForPeer(peer *Peer, cb func(prefix netip.Prefix)
 	}
 }
 
+func (node *trieEntry) remove() {
+	node.removeFromPeerEntries()
+	node.peer = nil
+	if node.child[0] != nil && node.child[1] != nil {
+		return
+	}
+	bit := 0
+	if node.child[0] == nil {
+		bit = 1
+	}
+	child := node.child[bit]
+	if child != nil {
+		child.parent = node.parent
+	}
+	*node.parent.parentBit = child
+	if node.child[0] != nil || node.child[1] != nil || node.parent.parentBitType > 1 {
+		node.zeroizePointers()
+		return
+	}
+	parent := (*trieEntry)(unsafe.Pointer(uintptr(unsafe.Pointer(node.parent.parentBit)) - unsafe.Offsetof(node.child) - unsafe.Sizeof(node.child[0])*uintptr(node.parent.parentBitType)))
+	if parent.peer != nil {
+		node.zeroizePointers()
+		return
+	}
+	child = parent.child[node.parent.parentBitType^1]
+	if child != nil {
+		child.parent = parent.parent
+	}
+	*parent.parent.parentBit = child
+	node.zeroizePointers()
+	parent.zeroizePointers()
+}
+
+func (table *AllowedIPs) Remove(prefix netip.Prefix, peer *Peer) {
+	table.mutex.Lock()
+	defer table.mutex.Unlock()
+	var node *trieEntry
+	var exact bool
+
+	if prefix.Addr().Is6() {
+		ip := prefix.Addr().As16()
+		node, exact = table.IPv6.nodePlacement(ip[:], uint8(prefix.Bits()))
+	} else if prefix.Addr().Is4() {
+		ip := prefix.Addr().As4()
+		node, exact = table.IPv4.nodePlacement(ip[:], uint8(prefix.Bits()))
+	} else {
+		panic(errors.New("removing unknown address type"))
+	}
+	if !exact || node == nil || peer != node.peer {
+		return
+	}
+	node.remove()
+}
+
 func (table *AllowedIPs) RemoveByPeer(peer *Peer) {
 	table.mutex.Lock()
 	defer table.mutex.Unlock()
@@ -230,38 +284,7 @@ func (table *AllowedIPs) RemoveByPeer(peer *Peer) {
 	var next *list.Element
 	for elem := peer.trieEntries.Front(); elem != nil; elem = next {
 		next = elem.Next()
-		node := elem.Value.(*trieEntry)
-
-		node.removeFromPeerEntries()
-		node.peer = nil
-		if node.child[0] != nil && node.child[1] != nil {
-			continue
-		}
-		bit := 0
-		if node.child[0] == nil {
-			bit = 1
-		}
-		child := node.child[bit]
-		if child != nil {
-			child.parent = node.parent
-		}
-		*node.parent.parentBit = child
-		if node.child[0] != nil || node.child[1] != nil || node.parent.parentBitType > 1 {
-			node.zeroizePointers()
-			continue
-		}
-		parent := (*trieEntry)(unsafe.Pointer(uintptr(unsafe.Pointer(node.parent.parentBit)) - unsafe.Offsetof(node.child) - unsafe.Sizeof(node.child[0])*uintptr(node.parent.parentBitType)))
-		if parent.peer != nil {
-			node.zeroizePointers()
-			continue
-		}
-		child = parent.child[node.parent.parentBitType^1]
-		if child != nil {
-			child.parent = parent.parent
-		}
-		*parent.parent.parentBit = child
-		node.zeroizePointers()
-		parent.zeroizePointers()
+		elem.Value.(*trieEntry).remove()
 	}
 }
 

device/allowedips_rand_test.go

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package device
@@ -83,7 +83,7 @@ func TestTrieRandom(t *testing.T) {
 	var peers []*Peer
 	var allowedIPs AllowedIPs
 
-	rand.Seed(1)
+	rng := rand.New(rand.NewSource(1))
 
 	for n := 0; n < NumberOfPeers; n++ {
 		peers = append(peers, &Peer{})
@@ -91,14 +91,14 @@ func TestTrieRandom(t *testing.T) {
 
 	for n := 0; n < NumberOfAddresses; n++ {
 		var addr4 [4]byte
-		rand.Read(addr4[:])
+		rng.Read(addr4[:])
 		cidr := uint8(rand.Intn(32) + 1)
 		index := rand.Intn(NumberOfPeers)
 		allowedIPs.Insert(netip.PrefixFrom(netip.AddrFrom4(addr4), int(cidr)), peers[index])
 		slow4 = slow4.Insert(addr4[:], cidr, peers[index])
 
 		var addr6 [16]byte
-		rand.Read(addr6[:])
+		rng.Read(addr6[:])
 		cidr = uint8(rand.Intn(128) + 1)
 		index = rand.Intn(NumberOfPeers)
 		allowedIPs.Insert(netip.PrefixFrom(netip.AddrFrom16(addr6), int(cidr)), peers[index])
@@ -109,7 +109,7 @@ func TestTrieRandom(t *testing.T) {
 	for p = 0; ; p++ {
 		for n := 0; n < NumberOfTests; n++ {
 			var addr4 [4]byte
-			rand.Read(addr4[:])
+			rng.Read(addr4[:])
 			peer1 := slow4.Lookup(addr4[:])
 			peer2 := allowedIPs.Lookup(addr4[:])
 			if peer1 != peer2 {
@@ -117,7 +117,7 @@ func TestTrieRandom(t *testing.T) {
 			}
 
 			var addr6 [16]byte
-			rand.Read(addr6[:])
+			rng.Read(addr6[:])
 			peer1 = slow6.Lookup(addr6[:])
 			peer2 = allowedIPs.Lookup(addr6[:])
 			if peer1 != peer2 {

device/allowedips_test.go

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package device
@@ -39,12 +39,12 @@ func TestCommonBits(t *testing.T) {
 	}
 }
 
-func benchmarkTrie(peerNumber, addressNumber, addressLength int, b *testing.B) {
+func benchmarkTrie(peerNumber, addressNumber, _ int, b *testing.B) {
 	var trie *trieEntry
 	var peers []*Peer
 	root := parentIndirection{&trie, 2}
 
-	rand.Seed(1)
+	rng := rand.New(rand.NewSource(1))
 
 	const AddressLength = 4
 
@@ -54,15 +54,15 @@ func benchmarkTrie(peerNumber, addressNumber, addressLength int, b *testing.B) {
 
 	for n := 0; n < addressNumber; n++ {
 		var addr [AddressLength]byte
-		rand.Read(addr[:])
-		cidr := uint8(rand.Uint32() % (AddressLength * 8))
-		index := rand.Int() % peerNumber
+		rng.Read(addr[:])
+		cidr := uint8(rng.Uint32() % (AddressLength * 8))
+		index := rng.Int() % peerNumber
 		root.insert(addr[:], cidr, peers[index])
 	}
 
 	for n := 0; n < b.N; n++ {
 		var addr [AddressLength]byte
-		rand.Read(addr[:])
+		rng.Read(addr[:])
 		trie.lookup(addr[:])
 	}
 }
@@ -101,6 +101,10 @@ func TestTrieIPv4(t *testing.T) {
 		allowedIPs.Insert(netip.PrefixFrom(netip.AddrFrom4([4]byte{a, b, c, d}), int(cidr)), peer)
 	}
 
+	remove := func(peer *Peer, a, b, c, d byte, cidr uint8) {
+		allowedIPs.Remove(netip.PrefixFrom(netip.AddrFrom4([4]byte{a, b, c, d}), int(cidr)), peer)
+	}
+
 	assertEQ := func(peer *Peer, a, b, c, d byte) {
 		p := allowedIPs.Lookup([]byte{a, b, c, d})
 		if p != peer {
@@ -176,6 +180,21 @@ func TestTrieIPv4(t *testing.T) {
 	allowedIPs.RemoveByPeer(a)
 
 	assertNEQ(a, 192, 168, 0, 1)
+
+	insert(a, 1, 0, 0, 0, 32)
+	insert(a, 192, 0, 0, 0, 24)
+	assertEQ(a, 1, 0, 0, 0)
+	assertEQ(a, 192, 0, 0, 1)
+	remove(a, 192, 0, 0, 0, 32)
+	assertEQ(a, 192, 0, 0, 1)
+	remove(nil, 192, 0, 0, 0, 24)
+	assertEQ(a, 192, 0, 0, 1)
+	remove(b, 192, 0, 0, 0, 24)
+	assertEQ(a, 192, 0, 0, 1)
+	remove(a, 192, 0, 0, 0, 24)
+	assertNEQ(a, 192, 0, 0, 1)
+	remove(a, 1, 0, 0, 0, 32)
+	assertNEQ(a, 1, 0, 0, 0)
 }
 
 /* Test ported from kernel implementation:
@@ -211,6 +230,15 @@ func TestTrieIPv6(t *testing.T) {
 		allowedIPs.Insert(netip.PrefixFrom(netip.AddrFrom16(*(*[16]byte)(addr)), int(cidr)), peer)
 	}
 
+	remove := func(peer *Peer, a, b, c, d uint32, cidr uint8) {
+		var addr []byte
+		addr = append(addr, expand(a)...)
+		addr = append(addr, expand(b)...)
+		addr = append(addr, expand(c)...)
+		addr = append(addr, expand(d)...)
+		allowedIPs.Remove(netip.PrefixFrom(netip.AddrFrom16(*(*[16]byte)(addr)), int(cidr)), peer)
+	}
+
 	assertEQ := func(peer *Peer, a, b, c, d uint32) {
 		var addr []byte
 		addr = append(addr, expand(a)...)
@@ -223,6 +251,18 @@ func TestTrieIPv6(t *testing.T) {
 		}
 	}
 
+	assertNEQ := func(peer *Peer, a, b, c, d uint32) {
+		var addr []byte
+		addr = append(addr, expand(a)...)
+		addr = append(addr, expand(b)...)
+		addr = append(addr, expand(c)...)
+		addr = append(addr, expand(d)...)
+		p := allowedIPs.Lookup(addr)
+		if p == peer {
+			t.Error("Assert NEQ failed")
+		}
+	}
+
 	insert(d, 0x26075300, 0x60006b00, 0, 0xc05f0543, 128)
 	insert(c, 0x26075300, 0x60006b00, 0, 0, 64)
 	insert(e, 0, 0, 0, 0, 0)
@@ -244,4 +284,21 @@ func TestTrieIPv6(t *testing.T) {
 	assertEQ(h, 0x24046800, 0x40040800, 0, 0)
 	assertEQ(h, 0x24046800, 0x40040800, 0x10101010, 0x10101010)
 	assertEQ(a, 0x24046800, 0x40040800, 0xdeadbeef, 0xdeadbeef)
+
+	insert(a, 0x24446801, 0x40e40800, 0xdeaebeef, 0xdefbeef, 128)
+	insert(a, 0x24446800, 0xf0e40800, 0xeeaebeef, 0, 98)
+	assertEQ(a, 0x24446801, 0x40e40800, 0xdeaebeef, 0xdefbeef)
+	assertEQ(a, 0x24446800, 0xf0e40800, 0xeeaebeef, 0x10101010)
+	remove(a, 0x24446801, 0x40e40800, 0xdeaebeef, 0xdefbeef, 96)
+	assertEQ(a, 0x24446801, 0x40e40800, 0xdeaebeef, 0xdefbeef)
+	remove(nil, 0x24446801, 0x40e40800, 0xdeaebeef, 0xdefbeef, 128)
+	assertEQ(a, 0x24446801, 0x40e40800, 0xdeaebeef, 0xdefbeef)
+	remove(b, 0x24446801, 0x40e40800, 0xdeaebeef, 0xdefbeef, 128)
+	assertEQ(a, 0x24446801, 0x40e40800, 0xdeaebeef, 0xdefbeef)
+	remove(a, 0x24446801, 0x40e40800, 0xdeaebeef, 0xdefbeef, 128)
+	assertNEQ(a, 0x24446801, 0x40e40800, 0xdeaebeef, 0xdefbeef)
+	remove(b, 0x24446800, 0xf0e40800, 0xeeaebeef, 0, 98)
+	assertEQ(a, 0x24446800, 0xf0e40800, 0xeeaebeef, 0x10101010)
+	remove(a, 0x24446800, 0xf0e40800, 0xeeaebeef, 0, 98)
+	assertNEQ(a, 0x24446800, 0xf0e40800, 0xeeaebeef, 0x10101010)
 }

device/bind_test.go

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package device
@@ -8,7 +8,7 @@ package device
 import (
 	"errors"
 
-	"golang.zx2c4.com/wireguard/conn"
+	"github.com/amnezia-vpn/amneziawg-go/v3/conn"
 )
 
 type DummyDatagram struct {

device/channels.go

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package device
@@ -19,13 +19,13 @@ import (
 // call wg.Done to remove the initial reference.
 // When the refcount hits 0, the queue's channel is closed.
 type outboundQueue struct {
-	c  chan *QueueOutboundElement
+	c  chan *QueueOutboundElementsContainer
 	wg sync.WaitGroup
 }
 
 func newOutboundQueue() *outboundQueue {
 	q := &outboundQueue{
-		c: make(chan *QueueOutboundElement, QueueOutboundSize),
+		c: make(chan *QueueOutboundElementsContainer, QueueOutboundSize),
 	}
 	q.wg.Add(1)
 	go func() {
@@ -37,13 +37,13 @@ func newOutboundQueue() *outboundQueue {
 
 // A inboundQueue is similar to an outboundQueue; see those docs.
 type inboundQueue struct {
-	c  chan *QueueInboundElement
+	c  chan *QueueInboundElementsContainer
 	wg sync.WaitGroup
 }
 
 func newInboundQueue() *inboundQueue {
 	q := &inboundQueue{
-		c: make(chan *QueueInboundElement, QueueInboundSize),
+		c: make(chan *QueueInboundElementsContainer, QueueInboundSize),
 	}
 	q.wg.Add(1)
 	go func() {
@@ -72,7 +72,7 @@ func newHandshakeQueue() *handshakeQueue {
 }
 
 type autodrainingInboundQueue struct {
-	c chan *[]*QueueInboundElement
+	c chan *QueueInboundElementsContainer
 }
 
 // newAutodrainingInboundQueue returns a channel that will be drained when it gets GC'd.
@@ -81,7 +81,7 @@ type autodrainingInboundQueue struct {
 // some other means, such as sending a sentinel nil values.
 func newAutodrainingInboundQueue(device *Device) *autodrainingInboundQueue {
 	q := &autodrainingInboundQueue{
-		c: make(chan *[]*QueueInboundElement, QueueInboundSize),
+		c: make(chan *QueueInboundElementsContainer, QueueInboundSize),
 	}
 	runtime.SetFinalizer(q, device.flushInboundQueue)
 	return q
@@ -90,13 +90,13 @@ func newAutodrainingInboundQueue(device *Device) *autodrainingInboundQueue {
 func (device *Device) flushInboundQueue(q *autodrainingInboundQueue) {
 	for {
 		select {
-		case elems := <-q.c:
-			for _, elem := range *elems {
-				elem.Lock()
+		case elemsContainer := <-q.c:
+			elemsContainer.Lock()
+			for _, elem := range elemsContainer.elems {
 				device.PutMessageBuffer(elem.buffer)
 				device.PutInboundElement(elem)
 			}
-			device.PutInboundElementsSlice(elems)
+			device.PutInboundElementsContainer(elemsContainer)
 		default:
 			return
 		}
@@ -104,7 +104,7 @@ func (device *Device) flushInboundQueue(q *autodrainingInboundQueue) {
 }
 
 type autodrainingOutboundQueue struct {
-	c chan *[]*QueueOutboundElement
+	c chan *QueueOutboundElementsContainer
 }
 
 // newAutodrainingOutboundQueue returns a channel that will be drained when it gets GC'd.
@@ -114,7 +114,7 @@ type autodrainingOutboundQueue struct {
 // All sends to the channel must be best-effort, because there may be no receivers.
 func newAutodrainingOutboundQueue(device *Device) *autodrainingOutboundQueue {
 	q := &autodrainingOutboundQueue{
-		c: make(chan *[]*QueueOutboundElement, QueueOutboundSize),
+		c: make(chan *QueueOutboundElementsContainer, QueueOutboundSize),
 	}
 	runtime.SetFinalizer(q, device.flushOutboundQueue)
 	return q
@@ -123,13 +123,13 @@ func newAutodrainingOutboundQueue(device *Device) *autodrainingOutboundQueue {
 func (device *Device) flushOutboundQueue(q *autodrainingOutboundQueue) {
 	for {
 		select {
-		case elems := <-q.c:
-			for _, elem := range *elems {
-				elem.Lock()
+		case elemsContainer := <-q.c:
+			elemsContainer.Lock()
+			for _, elem := range elemsContainer.elems {
 				device.PutMessageBuffer(elem.buffer)
 				device.PutOutboundElement(elem)
 			}
-			device.PutOutboundElementsSlice(elems)
+			device.PutOutboundElementsContainer(elemsContainer)
 		default:
 			return
 		}

device/constants.go

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package device
@@ -24,6 +24,7 @@ const (
 	CookieRefreshTime       = time.Second * 120
 	HandshakeInitationRate  = time.Second / 50
 	PaddingMultiple         = 16
+	DefaultUdpWindow        = 500
 )
 
 const (

device/cookie.go

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package device
@@ -118,6 +118,7 @@ func (st *CookieChecker) CreateReply(
 	msg []byte,
 	recv uint32,
 	src []byte,
+	msgType uint32,
 ) (*MessageCookieReply, error) {
 	st.RLock()
 
@@ -153,7 +154,7 @@ func (st *CookieChecker) CreateReply(
 	smac1 := smac2 - blake2s.Size128
 
 	reply := new(MessageCookieReply)
-	reply.Type = MessageCookieReplyType
+	reply.Type = msgType
 	reply.Receiver = recv
 
 	_, err := rand.Read(reply.Nonce[:])

device/cookie_test.go

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package device
@@ -99,7 +99,7 @@ func TestCookieMAC1(t *testing.T) {
 			0x8c, 0xe1, 0xe8, 0xfa, 0x67, 0x20, 0x80, 0x6d,
 		}
 		generator.AddMacs(msg)
-		reply, err := checker.CreateReply(msg, 1377, src)
+		reply, err := checker.CreateReply(msg, 1377, src, MessageCookieReplyType)
 		if err != nil {
 			t.Fatal("Failed to create cookie reply:", err)
 		}

device/device.go

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package device
@@ -11,10 +11,10 @@ import (
 	"sync/atomic"
 	"time"
 
-	"golang.zx2c4.com/wireguard/conn"
-	"golang.zx2c4.com/wireguard/ratelimiter"
-	"golang.zx2c4.com/wireguard/rwcancel"
-	"golang.zx2c4.com/wireguard/tun"
+	"github.com/amnezia-vpn/amneziawg-go/v3/conn"
+	"github.com/amnezia-vpn/amneziawg-go/v3/ratelimiter"
+	"github.com/amnezia-vpn/amneziawg-go/v3/rwcancel"
+	"github.com/amnezia-vpn/amneziawg-go/v3/tun"
 )
 
 type Device struct {
@@ -68,11 +68,11 @@ type Device struct {
 	cookieChecker CookieChecker
 
 	pool struct {
-		outboundElementsSlice *WaitPool
-		inboundElementsSlice  *WaitPool
-		messageBuffers        *WaitPool
-		inboundElements       *WaitPool
-		outboundElements      *WaitPool
+		inboundElementsContainer  *WaitPool
+		outboundElementsContainer *WaitPool
+		messageBuffers            *WaitPool
+		inboundElements           *WaitPool
+		outboundElements          *WaitPool
 	}
 
 	queue struct {
@@ -89,6 +89,46 @@ type Device struct {
 	ipcMutex sync.RWMutex
 	closed   chan struct{}
 	log      *Logger
+
+	junk struct {
+		min   atomic.Uint32
+		max   atomic.Uint32
+		count atomic.Uint32
+	}
+
+	headers struct {
+		init      AtomicUintRange
+		cookie    AtomicUintRange
+		response  AtomicUintRange
+		transport AtomicUintRange
+	}
+
+	paddings struct {
+		init      atomic.Uint32
+		response  atomic.Uint32
+		cookie    atomic.Uint32
+		transport atomic.Uint32
+	}
+
+	ipackets [5]*obfChain
+
+	headerProtection struct {
+		sync.RWMutex
+		key HeaderCipherKey
+	}
+
+	contentPaddingAddition AtomicUintRange
+
+	timings struct {
+		rekeyAfterTimeSec   AtomicUintRange
+		rekeyTimeoutSec     AtomicUintRange
+		rejectAfterTimeSec  AtomicUintRange
+		keepaliveTimeoutSec AtomicUintRange
+		maxHandshakeAttemps AtomicUintRange
+	}
+
+	randomTrailers atomic.Bool
+	disableCookies atomic.Bool
 }
 
 // deviceState represents the state of a Device.
@@ -162,7 +202,8 @@ func (device *Device) changeState(want deviceState) (err error) {
 			err = errDown
 		}
 	}
-	device.log.Verbosef("Interface state was %s, requested %s, now %s", old, want, device.deviceState())
+	device.log.Verbosef(
+		"Interface state was %s, requested %s, now %s", old, want, device.deviceState())
 	return
 }
 
@@ -182,7 +223,7 @@ func (device *Device) upLocked() error {
 	device.peers.RLock()
 	for _, peer := range device.peers.keyMap {
 		peer.Start()
-		if peer.persistentKeepaliveInterval.Load() > 0 {
+		if !peer.persistentKeepaliveInterval.Load().IsZero() {
 			peer.SendKeepalive()
 		}
 	}
@@ -282,6 +323,8 @@ func (device *Device) SetPrivateKey(sk NoisePrivateKey) error {
 }
 
 func NewDevice(tunDevice tun.Device, bind conn.Bind, logger *Logger) *Device {
+	var rang UintRange
+
 	device := new(Device)
 	device.state.state.Store(uint32(deviceStateDown))
 	device.closed = make(chan struct{})
@@ -298,6 +341,15 @@ func NewDevice(tunDevice tun.Device, bind conn.Bind, logger *Logger) *Device {
 	device.rate.limiter.Init()
 	device.indexTable.Init()
 
+	rang.FromUint32(MessageInitiationType, MessageInitiationType)
+	device.headers.init.Store(rang)
+	rang.FromUint32(MessageResponseType, MessageResponseType)
+	device.headers.response.Store(rang)
+	rang.FromUint32(MessageCookieReplyType, MessageCookieReplyType)
+	device.headers.cookie.Store(rang)
+	rang.FromUint32(MessageTransportType, MessageTransportType)
+	device.headers.transport.Store(rang)
+
 	device.PopulatePools()
 
 	// create queues
@@ -368,10 +420,10 @@ func (device *Device) RemoveAllPeers() {
 }
 
 func (device *Device) Close() {
-	device.ipcMutex.Lock()
-	defer device.ipcMutex.Unlock()
 	device.state.Lock()
 	defer device.state.Unlock()
+	device.ipcMutex.Lock()
+	defer device.ipcMutex.Unlock()
 	if device.isClosed() {
 		return
 	}
@@ -408,10 +460,12 @@ func (device *Device) SendKeepalivesToPeersWithCurrentKeypair() {
 		return
 	}
 
+	timeout := device.keychainExpireTime()
+
 	device.peers.RLock()
 	for _, peer := range device.peers.keyMap {
 		peer.keypairs.RLock()
-		sendKeepalive := peer.keypairs.current != nil && !peer.keypairs.current.created.Add(RejectAfterTime).Before(time.Now())
+		sendKeepalive := peer.keypairs.current != nil && !peer.keypairs.current.created.Add(timeout).Before(time.Now())
 		peer.keypairs.RUnlock()
 		if sendKeepalive {
 			peer.SendKeepalive()
@@ -461,11 +515,7 @@ func (device *Device) BindSetMark(mark uint32) error {
 	// clear cached source addresses
 	device.peers.RLock()
 	for _, peer := range device.peers.keyMap {
-		peer.Lock()
-		defer peer.Unlock()
-		if peer.endpoint != nil {
-			peer.endpoint.ClearSrc()
-		}
+		peer.markEndpointSrcForClearing()
 	}
 	device.peers.RUnlock()
 
@@ -515,11 +565,7 @@ func (device *Device) BindUpdate() error {
 	// clear cached source addresses
 	device.peers.RLock()
 	for _, peer := range device.peers.keyMap {
-		peer.Lock()
-		defer peer.Unlock()
-		if peer.endpoint != nil {
-			peer.endpoint.ClearSrc()
-		}
+		peer.markEndpointSrcForClearing()
 	}
 	device.peers.RUnlock()
 

device/device_test.go

@@ -1,29 +1,32 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package device
 
 import (
 	"bytes"
+	"context"
 	"encoding/hex"
 	"fmt"
 	"io"
 	"math/rand"
 	"net/netip"
 	"os"
+	"os/signal"
 	"runtime"
 	"runtime/pprof"
 	"sync"
-	"sync/atomic"
 	"testing"
 	"time"
 
-	"golang.zx2c4.com/wireguard/conn"
-	"golang.zx2c4.com/wireguard/conn/bindtest"
-	"golang.zx2c4.com/wireguard/tun"
-	"golang.zx2c4.com/wireguard/tun/tuntest"
+	"go.uber.org/atomic"
+
+	"github.com/amnezia-vpn/amneziawg-go/v3/conn"
+	"github.com/amnezia-vpn/amneziawg-go/v3/conn/bindtest"
+	"github.com/amnezia-vpn/amneziawg-go/v3/tun"
+	"github.com/amnezia-vpn/amneziawg-go/v3/tun/tuntest"
 )
 
 // uapiCfg returns a string that contains cfg formatted use with IpcSet.
@@ -50,7 +53,7 @@ func uapiCfg(cfg ...string) string {
 
 // genConfigs generates a pair of configs that connect to each other.
 // The configs use distinct, probably-usable ports.
-func genConfigs(tb testing.TB) (cfgs, endpointCfgs [2]string) {
+func genConfigs(tb testing.TB, cfg ...string) (cfgs, endpointCfgs [2]string) {
 	var key1, key2 NoisePrivateKey
 	_, err := rand.Read(key1[:])
 	if err != nil {
@@ -62,7 +65,8 @@ func genConfigs(tb testing.TB) (cfgs, endpointCfgs [2]string) {
 	}
 	pub1, pub2 := key1.publicKey(), key2.publicKey()
 
-	cfgs[0] = uapiCfg(
+	args0 := append([]string(nil), cfg...)
+	args0 = append(args0, []string{
 		"private_key", hex.EncodeToString(key1[:]),
 		"listen_port", "0",
 		"replace_peers", "true",
@@ -70,12 +74,16 @@ func genConfigs(tb testing.TB) (cfgs, endpointCfgs [2]string) {
 		"protocol_version", "1",
 		"replace_allowed_ips", "true",
 		"allowed_ip", "1.0.0.2/32",
-	)
+	}...)
+	cfgs[0] = uapiCfg(args0...)
+
 	endpointCfgs[0] = uapiCfg(
 		"public_key", hex.EncodeToString(pub2[:]),
 		"endpoint", "127.0.0.1:%d",
 	)
-	cfgs[1] = uapiCfg(
+
+	args1 := append([]string(nil), cfg...)
+	args1 = append(args1, []string{
 		"private_key", hex.EncodeToString(key2[:]),
 		"listen_port", "0",
 		"replace_peers", "true",
@@ -83,7 +91,9 @@ func genConfigs(tb testing.TB) (cfgs, endpointCfgs [2]string) {
 		"protocol_version", "1",
 		"replace_allowed_ips", "true",
 		"allowed_ip", "1.0.0.1/32",
-	)
+	}...)
+
+	cfgs[1] = uapiCfg(args1...)
 	endpointCfgs[1] = uapiCfg(
 		"public_key", hex.EncodeToString(pub1[:]),
 		"endpoint", "127.0.0.1:%d",
@@ -115,16 +125,21 @@ func (d SendDirection) String() string {
 	return "pong"
 }
 
-func (pair *testPair) Send(tb testing.TB, ping SendDirection, done chan struct{}) {
+func (pair *testPair) Send(
+	tb testing.TB,
+	ping SendDirection,
+	done chan struct{},
+) {
 	tb.Helper()
 	p0, p1 := pair[0], pair[1]
 	if !ping {
 		// pong is the new ping
 		p0, p1 = p1, p0
 	}
+
 	msg := tuntest.Ping(p0.ip, p1.ip)
 	p1.tun.Outbound <- msg
-	timer := time.NewTimer(5 * time.Second)
+	timer := time.NewTimer(6 * time.Second)
 	defer timer.Stop()
 	var err error
 	select {
@@ -149,8 +164,14 @@ func (pair *testPair) Send(tb testing.TB, ping SendDirection, done chan struct{}
 }
 
 // genTestPair creates a testPair.
-func genTestPair(tb testing.TB, realSocket bool) (pair testPair) {
-	cfg, endpointCfg := genConfigs(tb)
+func genTestPair(
+	tb testing.TB,
+	realSocket bool,
+	extraCfg ...string,
+) (pair testPair) {
+	var cfg, endpointCfg [2]string
+	cfg, endpointCfg = genConfigs(tb, extraCfg...)
+
 	var binds [2]conn.Bind
 	if realSocket {
 		binds[0], binds[1] = conn.NewDefaultBind(), conn.NewDefaultBind()
@@ -203,6 +224,74 @@ func TestTwoDevicePing(t *testing.T) {
 	})
 }
 
+// Run test with -race=false to avoid the race for setting the default msgTypes 2 times
+func TestAWGDevicePing(t *testing.T) {
+	goroutineLeakCheck(t)
+
+	pair := genTestPair(t, true,
+		"jc", "5",
+		"jmin", "500",
+		"jmax", "1000",
+		"s1", "15",
+		"s2", "18",
+		"s3", "20",
+		"s4", "25",
+		"h1", "123456-123500",
+		"h2", "67543-67550",
+		"h3", "123123-123200",
+		"h4", "32345-32350",
+	)
+	t.Run("ping 1.0.0.1", func(t *testing.T) {
+		pair.Send(t, Ping, nil)
+	})
+	t.Run("ping 1.0.0.2", func(t *testing.T) {
+		pair.Send(t, Pong, nil)
+	})
+}
+
+// Needs to be stopped with Ctrl-C
+func TestAWGHandshakeDevicePing(t *testing.T) {
+	t.Skip("This test is intended to be run manually, not as part of the test suite.")
+
+	signalContext, cancel := signal.NotifyContext(context.Background(), os.Interrupt)
+	defer cancel()
+	isRunning := atomic.NewBool(true)
+	go func() {
+		<-signalContext.Done()
+		fmt.Println("Waiting to finish")
+		isRunning.Store(false)
+	}()
+
+	goroutineLeakCheck(t)
+	pair := genTestPair(t, true,
+		"i1", "<b 0xf6ab3267fa><c><b 0xf6ab><t><r 10>",
+		"i2", "<b 0xf6ab3267fa><c><b 0xf6ab><t><rc 10>",
+		"i3", "<b 0xf6ab3267fa><c><b 0xf6ab><t><rd 10>",
+		"i4", "<b 0xf6ab3267fa><r 100>",
+		// "jc", "1",
+		// "jmin", "500",
+		// "jmax", "1000",
+		// "s1", "30",
+		// "s2", "40",
+		// "h1", "123456",
+		// "h2", "67543",
+		// "h4", "32345",
+		// "h3", "123123",
+	)
+	t.Run("ping 1.0.0.1", func(t *testing.T) {
+		for isRunning.Load() {
+			pair.Send(t, Ping, nil)
+			time.Sleep(2 * time.Second)
+		}
+	})
+	t.Run("ping 1.0.0.2", func(t *testing.T) {
+		for isRunning.Load() {
+			pair.Send(t, Pong, nil)
+			time.Sleep(2 * time.Second)
+		}
+	})
+}
+
 func TestUpDown(t *testing.T) {
 	goroutineLeakCheck(t)
 	const itrials = 50
@@ -423,29 +512,43 @@ type fakeBindSized struct {
 	size int
 }
 
-func (b *fakeBindSized) Open(port uint16) (fns []conn.ReceiveFunc, actualPort uint16, err error) {
+func (b *fakeBindSized) Open(
+	port uint16,
+) (fns []conn.ReceiveFunc, actualPort uint16, err error) {
 	return nil, 0, nil
 }
-func (b *fakeBindSized) Close() error                                  { return nil }
-func (b *fakeBindSized) SetMark(mark uint32) error                     { return nil }
-func (b *fakeBindSized) Send(bufs [][]byte, ep conn.Endpoint) error    { return nil }
+
+func (b *fakeBindSized) Close() error { return nil }
+
+func (b *fakeBindSized) SetMark(mark uint32) error { return nil }
+
+func (b *fakeBindSized) Send(bufs [][]byte, ep conn.Endpoint) error { return nil }
+
 func (b *fakeBindSized) ParseEndpoint(s string) (conn.Endpoint, error) { return nil, nil }
-func (b *fakeBindSized) BatchSize() int                                { return b.size }
+
+func (b *fakeBindSized) BatchSize() int { return b.size }
 
 type fakeTUNDeviceSized struct {
 	size int
 }
 
 func (t *fakeTUNDeviceSized) File() *os.File { return nil }
+
 func (t *fakeTUNDeviceSized) Read(bufs [][]byte, sizes []int, offset int) (n int, err error) {
 	return 0, nil
 }
+
 func (t *fakeTUNDeviceSized) Write(bufs [][]byte, offset int) (int, error) { return 0, nil }
-func (t *fakeTUNDeviceSized) MTU() (int, error)                            { return 0, nil }
-func (t *fakeTUNDeviceSized) Name() (string, error)                        { return "", nil }
-func (t *fakeTUNDeviceSized) Events() <-chan tun.Event                     { return nil }
-func (t *fakeTUNDeviceSized) Close() error                                 { return nil }
-func (t *fakeTUNDeviceSized) BatchSize() int                               { return t.size }
+
+func (t *fakeTUNDeviceSized) MTU() (int, error) { return 0, nil }
+
+func (t *fakeTUNDeviceSized) Name() (string, error) { return "", nil }
+
+func (t *fakeTUNDeviceSized) Events() <-chan tun.Event { return nil }
+
+func (t *fakeTUNDeviceSized) Close() error { return nil }
+
+func (t *fakeTUNDeviceSized) BatchSize() int { return t.size }
 
 func TestBatchSize(t *testing.T) {
 	d := Device{}

device/endpoint_test.go

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package device

device/indextable.go

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package device

device/ip.go

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package device

device/kdf_test.go

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package device

device/keypair.go

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package device
@@ -11,7 +11,7 @@ import (
 	"sync/atomic"
 	"time"
 
-	"golang.zx2c4.com/wireguard/replay"
+	"github.com/amnezia-vpn/amneziawg-go/v3/replay"
 )
 
 /* Due to limitations in Go and /x/crypto there is currently

device/logger.go

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package device

device/mobilequirks.go

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package device
@@ -11,9 +11,9 @@ func (device *Device) DisableSomeRoamingForBrokenMobileSemantics() {
 	device.net.brokenRoaming = true
 	device.peers.RLock()
 	for _, peer := range device.peers.keyMap {
-		peer.Lock()
-		peer.disableRoaming = peer.endpoint != nil
-		peer.Unlock()
+		peer.endpoint.Lock()
+		peer.endpoint.disableRoaming = peer.endpoint.val != nil
+		peer.endpoint.Unlock()
 	}
 	device.peers.RUnlock()
 }

device/noise-helpers.go

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package device

device/noise-protocol.go

@@ -1,21 +1,23 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package device
 
 import (
+	"crypto/rand"
 	"errors"
 	"fmt"
 	"sync"
 	"time"
 
 	"golang.org/x/crypto/blake2s"
+	"golang.org/x/crypto/chacha20"
 	"golang.org/x/crypto/chacha20poly1305"
 	"golang.org/x/crypto/poly1305"
 
-	"golang.zx2c4.com/wireguard/tai64n"
+	"github.com/amnezia-vpn/amneziawg-go/v3/tai64n"
 )
 
 type handshakeState int
@@ -53,10 +55,11 @@ const (
 )
 
 const (
-	MessageInitiationType  = 1
-	MessageResponseType    = 2
-	MessageCookieReplyType = 3
-	MessageTransportType   = 4
+	MessageUnknownType     uint32 = 0
+	MessageInitiationType  uint32 = 1
+	MessageResponseType    uint32 = 2
+	MessageCookieReplyType uint32 = 3
+	MessageTransportType   uint32 = 4
 )
 
 const (
@@ -193,8 +196,10 @@ func (device *Device) CreateMessageInitiation(peer *Peer) (*MessageInitiation, e
 
 	handshake.mixHash(handshake.remoteStatic[:])
 
+	msgType := device.headers.init.Load().PickOne()
+
 	msg := MessageInitiation{
-		Type:      MessageInitiationType,
+		Type:      msgType,
 		Ephemeral: handshake.localEphemeral.publicKey(),
 	}
 
@@ -367,7 +372,7 @@ func (device *Device) CreateMessageResponse(peer *Peer) (*MessageResponse, error
 	}
 
 	var msg MessageResponse
-	msg.Type = MessageResponseType
+	msg.Type = device.headers.response.Load().PickOne()
 	msg.Sender = handshake.localIndex
 	msg.Receiver = handshake.remoteIndex
 
@@ -623,3 +628,29 @@ func (peer *Peer) ReceivedWithKeypair(receivedKeypair *Keypair) bool {
 	keypairs.next.Store(nil)
 	return true
 }
+
+func (device *Device) JunkPackets() [][]byte {
+	var bufs [][]byte
+
+	min := device.junk.min.Load()
+	max := device.junk.max.Load()
+
+	for range device.junk.count.Load() {
+		buf := make([]byte, min+fastrandn(max-min))
+		rand.Read(buf)
+		bufs = append(bufs, buf)
+	}
+
+	return bufs
+}
+
+func (device *Device) HeaderProtectionCipher(salt []byte) (*chacha20.Cipher, error) {
+	device.headerProtection.RLock()
+	defer device.headerProtection.RUnlock()
+
+	if device.headerProtection.key.IsZero() {
+		return nil, nil
+	}
+
+	return chacha20.NewUnauthenticatedCipher(device.headerProtection.key[:], salt)
+}

device/noise-types.go

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package device
@@ -9,12 +9,18 @@ import (
 	"crypto/subtle"
 	"encoding/hex"
 	"errors"
+	"fmt"
+	"strconv"
+	"strings"
+	"sync/atomic"
 )
 
 const (
 	NoisePublicKeySize    = 32
 	NoisePrivateKeySize   = 32
 	NoisePresharedKeySize = 32
+	HeaderCipherKeySize   = 32
+	HeaderCipherNonceSize = 12
 )
 
 type (
@@ -22,6 +28,7 @@ type (
 	NoisePrivateKey   [NoisePrivateKeySize]byte
 	NoisePresharedKey [NoisePresharedKeySize]byte
 	NoiseNonce        uint64 // padded to 12-bytes
+	HeaderCipherKey   [HeaderCipherKeySize]byte
 )
 
 func loadExactHex(dst []byte, src string) error {
@@ -76,3 +83,104 @@ func (key NoisePublicKey) Equals(tar NoisePublicKey) bool {
 func (key *NoisePresharedKey) FromHex(src string) error {
 	return loadExactHex(key[:], src)
 }
+
+func (key HeaderCipherKey) IsZero() bool {
+	var zero HeaderCipherKey
+	return key.Equals(zero)
+}
+
+func (key HeaderCipherKey) Equals(tar HeaderCipherKey) bool {
+	return subtle.ConstantTimeCompare(key[:], tar[:]) == 1
+}
+
+func (key *HeaderCipherKey) FromHex(src string) error {
+	return loadExactHex(key[:], src)
+}
+
+type UintRange uint64
+
+func (r *UintRange) FromUint32(lo, hi uint32) {
+	*r = UintRange(uint64(hi)<<32 | uint64(lo))
+}
+
+func (r *UintRange) FromString(str string) error {
+	parts := strings.Split(str, "-")
+	if len(parts) < 1 || len(parts) > 2 {
+		return errors.New("wrong format")
+	}
+
+	lo, err := strconv.ParseUint(parts[0], 10, 32)
+	if err != nil {
+		return err
+	}
+
+	hi := lo
+	if len(parts) > 1 {
+		hi, err = strconv.ParseUint(parts[1], 10, 32)
+		if err != nil {
+			return err
+		}
+	}
+
+	if hi < lo {
+		return errors.New("wrong range specified")
+	}
+
+	r.FromUint32(uint32(lo), uint32(hi))
+	return nil
+}
+
+func (r UintRange) Contains(num uint32) bool {
+	lo, hi := uint32(r), uint32(r>>32)
+	return lo <= num && num <= hi
+}
+
+func (r UintRange) IsZero() bool {
+	return r == 0
+}
+
+func (r UintRange) PickOne() uint32 {
+	lo, hi := uint32(r), uint32(r>>32)
+	return lo + fastrandn(hi-lo+1)
+}
+
+func (r UintRange) ToString() string {
+	lo, hi := uint32(r), uint32(r>>32)
+
+	if lo == hi {
+		return fmt.Sprintf("%d", lo)
+	} else {
+		return fmt.Sprintf("%d-%d", lo, hi)
+	}
+}
+
+func (r UintRange) Overlap(right UintRange) bool {
+	l_lo, l_hi := uint32(r), uint32(r>>32)
+	r_lo, r_hi := uint32(right), uint32(right>>32)
+
+	return l_lo <= r_hi && r_lo <= l_hi
+}
+
+func (r UintRange) Lo() uint32 {
+	return uint32(r)
+}
+
+func (r UintRange) Hi() uint32 {
+	return uint32(r >> 32)
+}
+
+type AtomicUintRange struct {
+	v atomic.Uint64
+}
+
+func (a *AtomicUintRange) Load() UintRange {
+	return UintRange(a.v.Load())
+}
+
+func (a *AtomicUintRange) Store(r UintRange) {
+	a.v.Store(uint64(r))
+}
+
+func (a *AtomicUintRange) Swap(r UintRange) UintRange {
+	return UintRange(a.v.Swap(uint64(r)))
+}

device/noise_test.go

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package device
@@ -10,8 +10,8 @@ import (
 	"encoding/binary"
 	"testing"
 
-	"golang.zx2c4.com/wireguard/conn"
-	"golang.zx2c4.com/wireguard/tun/tuntest"
+	"github.com/amnezia-vpn/amneziawg-go/v3/conn"
+	"github.com/amnezia-vpn/amneziawg-go/v3/tun/tuntest"
 )
 
 func TestCurveWrappers(t *testing.T) {

device/obf.go

@@ -0,0 +1,143 @@
+package device
+
+import (
+	"errors"
+	"fmt"
+	"strings"
+)
+
+type obfBuilder func(val string) (obf, error)
+
+var obfBuilders = map[string]obfBuilder{
+	"b":  newBytesObf,
+	"t":  newTimestampObf,
+	"r":  newRandObf,
+	"rc": newRandCharObf,
+	"rd": newRandDigitsObf,
+	"d":  newDataObf,
+	"ds": newDataStringObf,
+	"dz": newDataSizeObf,
+}
+
+type obf interface {
+	Obfuscate(dst, src []byte)
+	Deobfuscate(dst, src []byte) bool
+	ObfuscatedLen(srcLen int) int
+	DeobfuscatedLen(srcLen int) int
+}
+
+type obfChain struct {
+	Spec string
+	obfs []obf
+}
+
+func newObfChain(spec string) (*obfChain, error) {
+	var (
+		obfs []obf
+		errs []error
+	)
+
+	remaining := spec[:]
+	for {
+		start := strings.IndexByte(remaining, '<')
+		if start == -1 {
+			break
+		}
+
+		end := strings.IndexByte(remaining[start:], '>')
+		if end == -1 {
+			return nil, errors.New("missing enclosing >")
+		}
+		end += start
+
+		tag := remaining[start+1 : end]
+		parts := strings.Fields(tag)
+		if len(parts) == 0 {
+			errs = append(errs, errors.New("empty tag"))
+			remaining = remaining[end+1:]
+			continue
+		}
+
+		key := parts[0]
+		builder, ok := obfBuilders[key]
+		if !ok {
+			errs = append(errs, fmt.Errorf("unknown tag <%s>", key))
+			remaining = remaining[end+1:]
+			continue
+		}
+
+		val := ""
+		if len(parts) > 1 {
+			val = parts[1]
+		}
+
+		o, err := builder(val)
+		if err != nil {
+			errs = append(errs, fmt.Errorf("failed to build <%s>: %w", key, err))
+			remaining = remaining[end+1:]
+			continue
+		}
+
+		obfs = append(obfs, o)
+		remaining = remaining[end+1:]
+	}
+
+	if len(errs) > 0 {
+		return nil, errors.Join(errs...)
+	}
+	if len(obfs) == 0 {
+		return nil, nil
+	}
+
+	return &obfChain{
+		Spec: spec,
+		obfs: obfs,
+	}, nil
+}
+
+func (c *obfChain) Obfuscate(dst, src []byte) {
+	written := 0
+	for _, o := range c.obfs {
+		obfLen := o.ObfuscatedLen(len(src))
+		o.Obfuscate(dst[written:written+obfLen], src)
+		written += obfLen
+	}
+}
+
+func (c *obfChain) Deobfuscate(dst, src []byte) bool {
+	dynamicLen := len(src) - c.ObfuscatedLen(0)
+
+	written, read := 0, 0
+
+	for _, o := range c.obfs {
+		deobfLen := o.DeobfuscatedLen(dynamicLen)
+		obfLen := o.ObfuscatedLen(deobfLen)
+
+		if !o.Deobfuscate(dst[written:written+deobfLen], src[read:read+obfLen]) {
+			return false
+		}
+
+		written += deobfLen
+		read += obfLen
+	}
+
+	return true
+}
+
+func (c *obfChain) ObfuscatedLen(n int) int {
+	total := 0
+	for _, o := range c.obfs {
+		total += o.ObfuscatedLen(n)
+	}
+	return total
+}
+
+func (c *obfChain) DeobfuscatedLen(n int) int {
+	dynamicLen := n - c.ObfuscatedLen(0)
+
+	total := 0
+	for _, o := range c.obfs {
+		total += o.DeobfuscatedLen(dynamicLen)
+	}
+	return total
+}

device/obf_bytes.go

@@ -0,0 +1,47 @@
+package device
+
+import (
+	"bytes"
+	"encoding/hex"
+	"errors"
+	"strings"
+)
+
+func newBytesObf(val string) (obf, error) {
+	val = strings.TrimPrefix(val, "0x")
+
+	if len(val) == 0 {
+		return nil, errors.New("empty argument")
+	}
+
+	if len(val)%2 != 0 {
+		return nil, errors.New("odd amount of symbols")
+	}
+
+	bytes, err := hex.DecodeString(val)
+	if err != nil {
+		return nil, err
+	}
+
+	return &bytesObf{data: bytes}, nil
+}
+
+type bytesObf struct {
+	data []byte
+}
+
+func (o *bytesObf) Obfuscate(dst, src []byte) {
+	copy(dst, o.data)
+}
+
+func (o *bytesObf) Deobfuscate(dst, src []byte) bool {
+	return bytes.Equal(o.data, src[:o.ObfuscatedLen(0)])
+}
+
+func (o *bytesObf) ObfuscatedLen(srcLen int) int {
+	return len(o.data)
+}
+
+func (o *bytesObf) DeobfuscatedLen(srcLen int) int {
+	return 0
+}

device/obf_data.go

@@ -0,0 +1,25 @@
+package device
+
+func newDataObf(val string) (obf, error) {
+	return &dataObf{}, nil
+}
+
+type dataObf struct {
+}
+
+func (obf *dataObf) Obfuscate(dst, src []byte) {
+	copy(dst, src)
+}
+
+func (obf *dataObf) Deobfuscate(dst, src []byte) bool {
+	copy(dst, src)
+	return true
+}
+
+func (o *dataObf) ObfuscatedLen(n int) int {
+	return n
+}
+
+func (o *dataObf) DeobfuscatedLen(n int) int {
+	return n
+}

device/obf_datasize.go

@@ -0,0 +1,38 @@
+package device
+
+import "strconv"
+
+func newDataSizeObf(val string) (obf, error) {
+	length, err := strconv.Atoi(val)
+	if err != nil {
+		return nil, err
+	}
+
+	return &dataSizeObf{
+		length: length,
+	}, nil
+}
+
+type dataSizeObf struct {
+	length int
+}
+
+func (o *dataSizeObf) Obfuscate(dst, src []byte) {
+	srcLen := len(src)
+	for i := o.length - 1; i >= 0; i-- {
+		dst[i] = byte(srcLen & 0xFF)
+		srcLen >>= 8
+	}
+}
+
+func (o *dataSizeObf) Deobfuscate(dst, src []byte) bool {
+	return true
+}
+
+func (o *dataSizeObf) ObfuscatedLen(srcLen int) int {
+	return o.length
+}
+
+func (o *dataSizeObf) DeobfuscatedLen(srcLen int) int {
+	return 0
+}

device/obf_datastring.go

@@ -0,0 +1,29 @@
+package device
+
+import (
+	"encoding/base64"
+)
+
+func newDataStringObf(val string) (obf, error) {
+	return &dataStringObf{}, nil
+}
+
+type dataStringObf struct {
+}
+
+func (o *dataStringObf) Obfuscate(dst, src []byte) {
+	base64.RawStdEncoding.Encode(dst, src)
+}
+
+func (o *dataStringObf) Deobfuscate(dst, src []byte) bool {
+	base64.RawStdEncoding.Decode(dst, src)
+	return true
+}
+
+func (o *dataStringObf) ObfuscatedLen(n int) int {
+	return base64.RawStdEncoding.EncodedLen(n)
+}
+
+func (o *dataStringObf) DeobfuscatedLen(n int) int {
+	return base64.RawStdEncoding.DecodedLen(n)
+}

device/obf_rand.go

@@ -0,0 +1,39 @@
+package device
+
+import (
+	"crypto/rand"
+	"strconv"
+)
+
+func newRandObf(val string) (obf, error) {
+	length, err := strconv.Atoi(val)
+	if err != nil {
+		return nil, err
+	}
+
+	return &randObf{
+		length: length,
+	}, nil
+}
+
+type randObf struct {
+	length int
+}
+
+func (o *randObf) Obfuscate(dst, src []byte) {
+	rand.Read(dst[:o.length])
+}
+
+func (o *randObf) Deobfuscate(dst, src []byte) bool {
+	// there is no way to validate randomness :)
+	// assume that it is always true
+	return true
+}
+
+func (o *randObf) ObfuscatedLen(n int) int {
+	return o.length
+}
+
+func (o *randObf) DeobfuscatedLen(n int) int {
+	return 0
+}

device/obf_randchars.go

@@ -0,0 +1,48 @@
+package device
+
+import (
+	"crypto/rand"
+	"strconv"
+	"unicode"
+)
+
+const chars52 = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"
+
+func newRandCharObf(val string) (obf, error) {
+	length, err := strconv.Atoi(val)
+	if err != nil {
+		return nil, err
+	}
+
+	return &randCharObf{
+		length: length,
+	}, nil
+}
+
+type randCharObf struct {
+	length int
+}
+
+func (o *randCharObf) Obfuscate(dst, src []byte) {
+	rand.Read(dst[:o.length])
+	for i := range dst[:o.length] {
+		dst[i] = chars52[dst[i]%52]
+	}
+}
+
+func (o *randCharObf) Deobfuscate(dst, src []byte) bool {
+	for _, b := range src[:o.length] {
+		if !unicode.IsLetter(rune(b)) {
+			return false
+		}
+	}
+	return true
+}
+
+func (o *randCharObf) ObfuscatedLen(n int) int {
+	return o.length
+}
+
+func (o *randCharObf) DeobfuscatedLen(n int) int {
+	return 0
+}

device/obf_randdigits.go

@@ -0,0 +1,48 @@
+package device
+
+import (
+	"crypto/rand"
+	"strconv"
+	"unicode"
+)
+
+const digits10 = "0123456789"
+
+func newRandDigitsObf(val string) (obf, error) {
+	length, err := strconv.Atoi(val)
+	if err != nil {
+		return nil, err
+	}
+
+	return &randDigitObf{
+		length: length,
+	}, nil
+}
+
+type randDigitObf struct {
+	length int
+}
+
+func (o *randDigitObf) Obfuscate(dst, src []byte) {
+	rand.Read(dst[:o.length])
+	for i := range dst[:o.length] {
+		dst[i] = digits10[dst[i]%10]
+	}
+}
+
+func (o *randDigitObf) Deobfuscate(dst, src []byte) bool {
+	for _, b := range src[:o.length] {
+		if !unicode.IsDigit(rune(b)) {
+			return false
+		}
+	}
+	return true
+}
+
+func (o *randDigitObf) ObfuscatedLen(n int) int {
+	return o.length
+}
+
+func (o *randDigitObf) DeobfuscatedLen(n int) int {
+	return 0
+}

device/obf_timestamp.go

@@ -0,0 +1,31 @@
+package device
+
+import (
+	"encoding/binary"
+	"time"
+)
+
+func newTimestampObf(_ string) (obf, error) {
+	return &timestampObf{}, nil
+}
+
+type timestampObf struct{}
+
+func (o *timestampObf) Obfuscate(dst, src []byte) {
+	t := uint32(time.Now().Unix())
+	binary.BigEndian.PutUint32(dst, t)
+}
+
+func (o *timestampObf) Deobfuscate(dst, src []byte) bool {
+	// replay attack check?
+	// requires time to be always synchronized
+	return true
+}
+
+func (o *timestampObf) ObfuscatedLen(n int) int {
+	return 4
+}
+
+func (o *timestampObf) DeobfuscatedLen(n int) int {
+	return 0
+}

device/peer.go

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package device
@@ -12,22 +12,25 @@ import (
 	"sync/atomic"
 	"time"
 
-	"golang.zx2c4.com/wireguard/conn"
+	"github.com/amnezia-vpn/amneziawg-go/v3/conn"
 )
 
 type Peer struct {
 	isRunning         atomic.Bool
-	sync.RWMutex      // Mostly protects endpoint, but is generally taken whenever we modify peer
 	keypairs          Keypairs
 	handshake         Handshake
 	device            *Device
-	endpoint          conn.Endpoint
 	stopping          sync.WaitGroup // routines pending stop
 	txBytes           atomic.Uint64  // bytes send to peer (endpoint)
 	rxBytes           atomic.Uint64  // bytes received from peer
 	lastHandshakeNano atomic.Int64   // nano seconds since epoch
 
-	disableRoaming bool
+	endpoint struct {
+		sync.Mutex
+		val            conn.Endpoint
+		clearSrcOnTx   bool // signal to val.ClearSrc() prior to next packet transmission
+		disableRoaming bool
+	}
 
 	timers struct {
 		retransmitHandshake     *Timer
@@ -36,6 +39,7 @@ type Peer struct {
 		zeroKeyMaterial         *Timer
 		persistentKeepalive     *Timer
 		handshakeAttempts       atomic.Uint32
+		maxHandshakeAttempts    atomic.Uint32
 		needAnotherKeepalive    atomic.Bool
 		sentLastMinuteHandshake atomic.Bool
 	}
@@ -45,14 +49,15 @@ type Peer struct {
 	}
 
 	queue struct {
-		staged   chan *[]*QueueOutboundElement // staged packets before a handshake is available
-		outbound *autodrainingOutboundQueue    // sequential ordering of udp transmission
-		inbound  *autodrainingInboundQueue     // sequential ordering of tun writing
+		staged   chan *QueueOutboundElementsContainer // staged packets before a handshake is available
+		outbound *autodrainingOutboundQueue           // sequential ordering of udp transmission
+		inbound  *autodrainingInboundQueue            // sequential ordering of tun writing
 	}
 
 	cookieGenerator             CookieGenerator
 	trieEntries                 list.List
-	persistentKeepaliveInterval atomic.Uint32
+	persistentKeepaliveInterval AtomicUintRange
+	udpWindow                   atomic.Uint32
 }
 
 func (device *Device) NewPeer(pk NoisePublicKey) (*Peer, error) {
@@ -74,14 +79,14 @@ func (device *Device) NewPeer(pk NoisePublicKey) (*Peer, error) {
 
 	// create peer
 	peer := new(Peer)
-	peer.Lock()
-	defer peer.Unlock()
+
+	peer.udpWindow.Store(DefaultUdpWindow)
 
 	peer.cookieGenerator.Init(pk)
 	peer.device = device
 	peer.queue.outbound = newAutodrainingOutboundQueue(device)
 	peer.queue.inbound = newAutodrainingInboundQueue(device)
-	peer.queue.staged = make(chan *[]*QueueOutboundElement, QueueStagedSize)
+	peer.queue.staged = make(chan *QueueOutboundElementsContainer, QueueStagedSize)
 
 	// map public key
 	_, ok := device.peers.keyMap[pk]
@@ -97,7 +102,11 @@ func (device *Device) NewPeer(pk NoisePublicKey) (*Peer, error) {
 	handshake.mutex.Unlock()
 
 	// reset endpoint
-	peer.endpoint = nil
+	peer.endpoint.Lock()
+	peer.endpoint.val = nil
+	peer.endpoint.disableRoaming = false
+	peer.endpoint.clearSrcOnTx = false
+	peer.endpoint.Unlock()
 
 	// init timers
 	peer.timersInit()
@@ -116,14 +125,19 @@ func (peer *Peer) SendBuffers(buffers [][]byte) error {
 		return nil
 	}
 
-	peer.RLock()
-	defer peer.RUnlock()
-
-	if peer.endpoint == nil {
+	peer.endpoint.Lock()
+	endpoint := peer.endpoint.val
+	if endpoint == nil {
+		peer.endpoint.Unlock()
 		return errors.New("no known endpoint for peer")
 	}
+	if peer.endpoint.clearSrcOnTx {
+		endpoint.ClearSrc()
+		peer.endpoint.clearSrcOnTx = false
+	}
+	peer.endpoint.Unlock()
 
-	err := peer.device.net.bind.Send(buffers, peer.endpoint)
+	err := peer.device.net.bind.Send(buffers, endpoint)
 	if err == nil {
 		var totalLen uint64
 		for _, b := range buffers {
@@ -182,7 +196,7 @@ func (peer *Peer) Start() {
 	peer.stopping.Add(2)
 
 	peer.handshake.mutex.Lock()
-	peer.handshake.lastSentHandshake = time.Now().Add(-(RekeyTimeout + time.Second))
+	peer.handshake.lastSentHandshake = time.Now().Add(-(peer.device.rekeyMinTimeout() + time.Second))
 	peer.handshake.mutex.Unlock()
 
 	peer.device.queue.encryption.wg.Add(1) // keep encryption queue open for our writes
@@ -232,7 +246,7 @@ func (peer *Peer) ExpireCurrentKeypairs() {
 	handshake.mutex.Lock()
 	peer.device.indexTable.Delete(handshake.localIndex)
 	handshake.Clear()
-	peer.handshake.lastSentHandshake = time.Now().Add(-(RekeyTimeout + time.Second))
+	peer.handshake.lastSentHandshake = time.Now().Add(-(peer.device.rekeyMinTimeout() + time.Second))
 	handshake.mutex.Unlock()
 
 	keypairs := &peer.keypairs
@@ -267,10 +281,23 @@ func (peer *Peer) Stop() {
 }
 
 func (peer *Peer) SetEndpointFromPacket(endpoint conn.Endpoint) {
-	if peer.disableRoaming {
+	peer.endpoint.Lock()
+	defer peer.endpoint.Unlock()
+	if peer.endpoint.disableRoaming {
 		return
 	}
-	peer.Lock()
-	peer.endpoint = endpoint
-	peer.Unlock()
+	if peer.endpoint.val != endpoint {
+		peer.udpWindow.Store(DefaultUdpWindow)
+	}
+	peer.endpoint.clearSrcOnTx = false
+	peer.endpoint.val = endpoint
+}
+
+func (peer *Peer) markEndpointSrcForClearing() {
+	peer.endpoint.Lock()
+	defer peer.endpoint.Unlock()
+	if peer.endpoint.val == nil {
+		return
+	}
+	peer.endpoint.clearSrcOnTx = true
 }

device/pools.go

@@ -1,20 +1,19 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package device
 
 import (
 	"sync"
-	"sync/atomic"
 )
 
 type WaitPool struct {
 	pool  sync.Pool
 	cond  sync.Cond
 	lock  sync.Mutex
-	count atomic.Uint32
+	count uint32 // Get calls not yet Put back
 	max   uint32
 }
 
@@ -27,10 +26,10 @@ func NewWaitPool(max uint32, new func() any) *WaitPool {
 func (p *WaitPool) Get() any {
 	if p.max != 0 {
 		p.lock.Lock()
-		for p.count.Load() >= p.max {
+		for p.count >= p.max {
 			p.cond.Wait()
 		}
-		p.count.Add(1)
+		p.count++
 		p.lock.Unlock()
 	}
 	return p.pool.Get()
@@ -41,18 +40,20 @@ func (p *WaitPool) Put(x any) {
 	if p.max == 0 {
 		return
 	}
-	p.count.Add(^uint32(0))
+	p.lock.Lock()
+	defer p.lock.Unlock()
+	p.count--
 	p.cond.Signal()
 }
 
 func (device *Device) PopulatePools() {
-	device.pool.outboundElementsSlice = NewWaitPool(PreallocatedBuffersPerPool, func() any {
-		s := make([]*QueueOutboundElement, 0, device.BatchSize())
-		return &s
-	})
-	device.pool.inboundElementsSlice = NewWaitPool(PreallocatedBuffersPerPool, func() any {
+	device.pool.inboundElementsContainer = NewWaitPool(PreallocatedBuffersPerPool, func() any {
 		s := make([]*QueueInboundElement, 0, device.BatchSize())
-		return &s
+		return &QueueInboundElementsContainer{elems: s}
+	})
+	device.pool.outboundElementsContainer = NewWaitPool(PreallocatedBuffersPerPool, func() any {
+		s := make([]*QueueOutboundElement, 0, device.BatchSize())
+		return &QueueOutboundElementsContainer{elems: s}
 	})
 	device.pool.messageBuffers = NewWaitPool(PreallocatedBuffersPerPool, func() any {
 		return new([MaxMessageSize]byte)
@@ -65,28 +66,32 @@ func (device *Device) PopulatePools() {
 	})
 }
 
-func (device *Device) GetOutboundElementsSlice() *[]*QueueOutboundElement {
-	return device.pool.outboundElementsSlice.Get().(*[]*QueueOutboundElement)
+func (device *Device) GetInboundElementsContainer() *QueueInboundElementsContainer {
+	c := device.pool.inboundElementsContainer.Get().(*QueueInboundElementsContainer)
+	c.Mutex = sync.Mutex{}
+	return c
 }
 
-func (device *Device) PutOutboundElementsSlice(s *[]*QueueOutboundElement) {
-	for i := range *s {
-		(*s)[i] = nil
+func (device *Device) PutInboundElementsContainer(c *QueueInboundElementsContainer) {
+	for i := range c.elems {
+		c.elems[i] = nil
 	}
-	*s = (*s)[:0]
-	device.pool.outboundElementsSlice.Put(s)
+	c.elems = c.elems[:0]
+	device.pool.inboundElementsContainer.Put(c)
 }
 
-func (device *Device) GetInboundElementsSlice() *[]*QueueInboundElement {
-	return device.pool.inboundElementsSlice.Get().(*[]*QueueInboundElement)
+func (device *Device) GetOutboundElementsContainer() *QueueOutboundElementsContainer {
+	c := device.pool.outboundElementsContainer.Get().(*QueueOutboundElementsContainer)
+	c.Mutex = sync.Mutex{}
+	return c
 }
 
-func (device *Device) PutInboundElementsSlice(s *[]*QueueInboundElement) {
-	for i := range *s {
-		(*s)[i] = nil
+func (device *Device) PutOutboundElementsContainer(c *QueueOutboundElementsContainer) {
+	for i := range c.elems {
+		c.elems[i] = nil
 	}
-	*s = (*s)[:0]
-	device.pool.inboundElementsSlice.Put(s)
+	c.elems = c.elems[:0]
+	device.pool.outboundElementsContainer.Put(c)
 }
 
 func (device *Device) GetMessageBuffer() *[MaxMessageSize]byte {

device/pools_test.go

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package device
@@ -32,7 +32,9 @@ func TestWaitPool(t *testing.T) {
 	wg.Add(workers)
 	var max atomic.Uint32
 	updateMax := func() {
-		count := p.count.Load()
+		p.lock.Lock()
+		count := p.count
+		p.lock.Unlock()
 		if count > p.max {
 			t.Errorf("count (%d) > max (%d)", count, p.max)
 		}

device/queueconstants_android.go

@@ -1,11 +1,11 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package device
 
-import "golang.zx2c4.com/wireguard/conn"
+import "github.com/amnezia-vpn/amneziawg-go/v3/conn"
 
 /* Reduce memory consumption for Android */
 
@@ -14,6 +14,6 @@ const (
 	QueueOutboundSize          = 1024
 	QueueInboundSize           = 1024
 	QueueHandshakeSize         = 1024
-	MaxSegmentSize             = 2200
+	MaxSegmentSize             = (1 << 16) - 1 // largest possible UDP datagram
 	PreallocatedBuffersPerPool = 4096
 )

device/queueconstants_default.go

@@ -2,12 +2,12 @@
 
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package device
 
-import "golang.zx2c4.com/wireguard/conn"
+import "github.com/amnezia-vpn/amneziawg-go/v3/conn"
 
 const (
 	QueueStagedSize            = conn.IdealBatchSize

device/queueconstants_ios.go

@@ -2,7 +2,7 @@
 
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package device

device/queueconstants_windows.go

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package device

device/race_disabled_test.go

@@ -2,7 +2,7 @@
 
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package device

device/race_enabled_test.go

@@ -2,7 +2,7 @@
 
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package device

device/receive.go

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package device
@@ -13,10 +13,10 @@ import (
 	"sync"
 	"time"
 
+	"github.com/amnezia-vpn/amneziawg-go/v3/conn"
 	"golang.org/x/crypto/chacha20poly1305"
 	"golang.org/x/net/ipv4"
 	"golang.org/x/net/ipv6"
-	"golang.zx2c4.com/wireguard/conn"
 )
 
 type QueueHandshakeElement struct {
@@ -27,12 +27,17 @@ type QueueHandshakeElement struct {
 }
 
 type QueueInboundElement struct {
-	sync.Mutex
 	buffer   *[MaxMessageSize]byte
 	packet   []byte
 	counter  uint64
 	keypair  *Keypair
 	endpoint conn.Endpoint
+	padding  uint32
+}
+
+type QueueInboundElementsContainer struct {
+	sync.Mutex
+	elems []*QueueInboundElement
 }
 
 // clearPointers clears elem fields that contain pointers.
@@ -55,7 +60,8 @@ func (peer *Peer) keepKeyFreshReceiving() {
 		return
 	}
 	keypair := peer.keypairs.Current()
-	if keypair != nil && keypair.isInitiator && time.Since(keypair.created) > (RejectAfterTime-KeepaliveTimeout-RekeyTimeout) {
+
+	if keypair != nil && keypair.isInitiator && time.Since(keypair.created) > peer.device.keyRefreshTimeoutReceiving() {
 		peer.timers.sentLastMinuteHandshake.Store(true)
 		peer.SendHandshakeInitiation(false)
 	}
@@ -66,7 +72,10 @@ func (peer *Peer) keepKeyFreshReceiving() {
  * Every time the bind is updated a new routine is started for
  * IPv4 and IPv6 (separately)
  */
-func (device *Device) RoutineReceiveIncoming(maxBatchSize int, recv conn.ReceiveFunc) {
+func (device *Device) RoutineReceiveIncoming(
+	maxBatchSize int,
+	recv conn.ReceiveFunc,
+) {
 	recvName := recv.PrettyName()
 	defer func() {
 		device.log.Verbosef("Routine: receive incoming %s - stopped", recvName)
@@ -87,16 +96,17 @@ func (device *Device) RoutineReceiveIncoming(maxBatchSize int, recv conn.Receive
 		count       int
 		endpoints   = make([]conn.Endpoint, maxBatchSize)
 		deathSpiral int
-		elemsByPeer = make(map[*Peer]*[]*QueueInboundElement, maxBatchSize)
+		elemsByPeer = make(map[*Peer]*QueueInboundElementsContainer, maxBatchSize)
+		typeHashBuf [4]byte
 	)
 
-	for i := range bufsArrs {
+	for i := range maxBatchSize {
 		bufsArrs[i] = device.GetMessageBuffer()
 		bufs[i] = bufsArrs[i][:]
 	}
 
 	defer func() {
-		for i := 0; i < maxBatchSize; i++ {
+		for i := range maxBatchSize {
 			if bufsArrs[i] != nil {
 				device.PutMessageBuffer(bufsArrs[i])
 			}
@@ -129,9 +139,31 @@ func (device *Device) RoutineReceiveIncoming(maxBatchSize int, recv conn.Receive
 			}
 
 			// check size of packet
-
 			packet := bufsArrs[i][:size]
-			msgType := binary.LittleEndian.Uint32(packet[:4])
+
+			cip, err := device.HeaderProtectionCipher(packet[:HeaderCipherNonceSize])
+			if err != nil {
+				device.log.Errorf("Failed to initialize header cipher")
+				continue
+			}
+
+			typeHash := typeHashBuf[:]
+			clear(typeHash)
+			if cip != nil {
+				cip.XORKeyStream(typeHash, typeHash)
+			}
+
+			// get message padding and type based on information from S1-S4 and H1-H4
+			msgSize, msgType, padding := device.DeterminePacketTypeAndPadding(packet, typeHash)
+
+			packet = packet[padding:]
+			if msgType != MessageTransportType {
+				packet = packet[:msgSize]
+			}
+
+			if cip != nil {
+				applyHash(packet[:4], packet[:4], typeHash)
+			}
 
 			switch msgType {
 
@@ -144,6 +176,9 @@ func (device *Device) RoutineReceiveIncoming(maxBatchSize int, recv conn.Receive
 				if len(packet) < MessageTransportSize {
 					continue
 				}
+				if cip != nil {
+					cip.XORKeyStream(packet[4:MessageTransportHeaderSize], packet[4:MessageTransportHeaderSize])
+				}
 
 				// lookup key pair
 
@@ -158,7 +193,7 @@ func (device *Device) RoutineReceiveIncoming(maxBatchSize int, recv conn.Receive
 
 				// check keypair expiry
 
-				if keypair.created.Add(RejectAfterTime).Before(time.Now()) {
+				if keypair.created.Add(device.keychainExpireTime()).Before(time.Now()) {
 					continue
 				}
 
@@ -170,15 +205,15 @@ func (device *Device) RoutineReceiveIncoming(maxBatchSize int, recv conn.Receive
 				elem.keypair = keypair
 				elem.endpoint = endpoints[i]
 				elem.counter = 0
-				elem.Mutex = sync.Mutex{}
-				elem.Lock()
+				elem.padding = padding
 
 				elemsForPeer, ok := elemsByPeer[peer]
 				if !ok {
-					elemsForPeer = device.GetInboundElementsSlice()
+					elemsForPeer = device.GetInboundElementsContainer()
+					elemsForPeer.Lock()
 					elemsByPeer[peer] = elemsForPeer
 				}
-				*elemsForPeer = append(*elemsForPeer, elem)
+				elemsForPeer.elems = append(elemsForPeer.elems, elem)
 				bufsArrs[i] = device.GetMessageBuffer()
 				bufs[i] = bufsArrs[i][:]
 				continue
@@ -189,16 +224,25 @@ func (device *Device) RoutineReceiveIncoming(maxBatchSize int, recv conn.Receive
 				if len(packet) != MessageInitiationSize {
 					continue
 				}
+				if cip != nil {
+					cip.XORKeyStream(packet[4:MessageInitiationSize], packet[4:MessageInitiationSize])
+				}
 
 			case MessageResponseType:
 				if len(packet) != MessageResponseSize {
 					continue
 				}
+				if cip != nil {
+					cip.XORKeyStream(packet[4:MessageResponseSize], packet[4:MessageResponseSize])
+				}
 
 			case MessageCookieReplyType:
 				if len(packet) != MessageCookieReplySize {
 					continue
 				}
+				if cip != nil {
+					cip.XORKeyStream(packet[4:MessageCookieReplySize], packet[4:MessageCookieReplySize])
+				}
 
 			default:
 				device.log.Verbosef("Received message with unknown type")
@@ -217,18 +261,16 @@ func (device *Device) RoutineReceiveIncoming(maxBatchSize int, recv conn.Receive
 			default:
 			}
 		}
-		for peer, elems := range elemsByPeer {
+		for peer, elemsContainer := range elemsByPeer {
 			if peer.isRunning.Load() {
-				peer.queue.inbound.c <- elems
-				for _, elem := range *elems {
-					device.queue.decryption.c <- elem
-				}
+				peer.queue.inbound.c <- elemsContainer
+				device.queue.decryption.c <- elemsContainer
 			} else {
-				for _, elem := range *elems {
+				for _, elem := range elemsContainer.elems {
 					device.PutMessageBuffer(elem.buffer)
 					device.PutInboundElement(elem)
 				}
-				device.PutInboundElementsSlice(elems)
+				device.PutInboundElementsContainer(elemsContainer)
 			}
 			delete(elemsByPeer, peer)
 		}
@@ -241,26 +283,28 @@ func (device *Device) RoutineDecryption(id int) {
 	defer device.log.Verbosef("Routine: decryption worker %d - stopped", id)
 	device.log.Verbosef("Routine: decryption worker %d - started", id)
 
-	for elem := range device.queue.decryption.c {
-		// split message into fields
-		counter := elem.packet[MessageTransportOffsetCounter:MessageTransportOffsetContent]
-		content := elem.packet[MessageTransportOffsetContent:]
+	for elemsContainer := range device.queue.decryption.c {
+		for _, elem := range elemsContainer.elems {
+			// split message into fields
+			counter := elem.packet[MessageTransportOffsetCounter:MessageTransportOffsetContent]
+			content := elem.packet[MessageTransportOffsetContent:]
 
-		// decrypt and release to consumer
-		var err error
-		elem.counter = binary.LittleEndian.Uint64(counter)
-		// copy counter to nonce
-		binary.LittleEndian.PutUint64(nonce[0x4:0xc], elem.counter)
-		elem.packet, err = elem.keypair.receive.Open(
-			content[:0],
-			nonce[:],
-			content,
-			nil,
-		)
-		if err != nil {
-			elem.packet = nil
+			// decrypt and release to consumer
+			var err error
+			elem.counter = binary.LittleEndian.Uint64(counter)
+			// copy counter to nonce
+			binary.LittleEndian.PutUint64(nonce[0x4:0xc], elem.counter)
+			elem.packet, err = elem.keypair.receive.Open(
+				content[:0],
+				nonce[:],
+				content,
+				nil,
+			)
+			if err != nil {
+				elem.packet = nil
+			}
 		}
-		elem.Unlock()
+		elemsContainer.Unlock()
 	}
 }
 
@@ -274,7 +318,6 @@ func (device *Device) RoutineHandshake(id int) {
 	device.log.Verbosef("Routine: handshake worker %d - started", id)
 
 	for elem := range device.queue.handshake.c {
-
 		// handle cookie fields and ratelimiting
 
 		switch elem.msgType {
@@ -302,9 +345,14 @@ func (device *Device) RoutineHandshake(id int) {
 			// consume reply
 
 			if peer := entry.peer; peer.isRunning.Load() {
-				device.log.Verbosef("Receiving cookie response from %s", elem.endpoint.DstToString())
+				device.log.Verbosef(
+					"Receiving cookie response from %s",
+					elem.endpoint.DstToString(),
+				)
 				if !peer.cookieGenerator.ConsumeReply(&reply) {
-					device.log.Verbosef("Could not decrypt invalid cookie response")
+					device.log.Verbosef(
+						"Could not decrypt invalid cookie response",
+					)
 				}
 			}
 
@@ -321,7 +369,8 @@ func (device *Device) RoutineHandshake(id int) {
 
 			// endpoints destination address is the source of the datagram
 
-			if device.IsUnderLoad() {
+			disableCookies := device.disableCookies.Load()
+			if !disableCookies && device.IsUnderLoad() {
 
 				// verify MAC2 field
 
@@ -346,9 +395,7 @@ func (device *Device) RoutineHandshake(id int) {
 
 		switch elem.msgType {
 		case MessageInitiationType:
-
 			// unmarshal
-
 			var msg MessageInitiation
 			reader := bytes.NewReader(elem.packet)
 			err := binary.Read(reader, binary.LittleEndian, &msg)
@@ -357,8 +404,10 @@ func (device *Device) RoutineHandshake(id int) {
 				goto skip
 			}
 
-			// consume initiation
+			// have to reassign msgType for ranged msgType to work
+			msg.Type = elem.msgType
 
+			// consume initiation
 			peer := device.ConsumeMessageInitiation(&msg)
 			if peer == nil {
 				device.log.Verbosef("Received invalid initiation message from %s", elem.endpoint.DstToString())
@@ -390,6 +439,9 @@ func (device *Device) RoutineHandshake(id int) {
 				goto skip
 			}
 
+			// have to reassign msgType for ranged msgType to work
+			msg.Type = elem.msgType
+
 			// consume response
 
 			peer := device.ConsumeMessageResponse(&msg)
@@ -437,12 +489,15 @@ func (peer *Peer) RoutineSequentialReceiver(maxBatchSize int) {
 
 	bufs := make([][]byte, 0, maxBatchSize)
 
-	for elems := range peer.queue.inbound.c {
-		if elems == nil {
+	for elemsContainer := range peer.queue.inbound.c {
+		if elemsContainer == nil {
 			return
 		}
-		for _, elem := range *elems {
-			elem.Lock()
+		elemsContainer.Lock()
+		validTailPacket := -1
+		dataPacketReceived := false
+		rxBytesLen := uint64(0)
+		for i, elem := range elemsContainer.elems {
 			if elem.packet == nil {
 				// decryption failed
 				continue
@@ -452,21 +507,24 @@ func (peer *Peer) RoutineSequentialReceiver(maxBatchSize int) {
 				continue
 			}
 
-			peer.SetEndpointFromPacket(elem.endpoint)
+			validTailPacket = i
 			if peer.ReceivedWithKeypair(elem.keypair) {
+				peer.SetEndpointFromPacket(elem.endpoint)
 				peer.timersHandshakeComplete()
 				peer.SendStagedPackets()
 			}
-			peer.keepKeyFreshReceiving()
-			peer.timersAnyAuthenticatedPacketTraversal()
-			peer.timersAnyAuthenticatedPacketReceived()
-			peer.rxBytes.Add(uint64(len(elem.packet) + MinMessageSize))
+			rxBytesLen += uint64(len(elem.packet) + MinMessageSize)
 
-			if len(elem.packet) == 0 {
+			udpWindow := elem.padding + MessageTransportHeaderSize + uint32(len(elem.packet))
+			if peer.udpWindow.Load() < udpWindow {
+				peer.udpWindow.Store(udpWindow)
+			}
+
+			if len(elem.packet) == 0 || elem.packet[0] == 0 {
 				device.log.Verbosef("%v - Receiving keepalive packet", peer)
 				continue
 			}
-			peer.timersDataReceived()
+			dataPacketReceived = true
 
 			switch elem.packet[0] >> 4 {
 			case 4:
@@ -503,11 +561,25 @@ func (peer *Peer) RoutineSequentialReceiver(maxBatchSize int) {
 				}
 
 			default:
-				device.log.Verbosef("Packet with invalid IP version from %v", peer)
+				device.log.Verbosef(
+					"Packet with invalid IP version from %v",
+					peer,
+				)
 				continue
 			}
 
-			bufs = append(bufs, elem.buffer[:MessageTransportOffsetContent+len(elem.packet)])
+			bufs = append(bufs, elem.buffer[int(elem.padding):int(elem.padding)+MessageTransportHeaderSize+len(elem.packet)])
+		}
+
+		peer.rxBytes.Add(rxBytesLen)
+		if validTailPacket >= 0 {
+			peer.SetEndpointFromPacket(elemsContainer.elems[validTailPacket].endpoint)
+			peer.keepKeyFreshReceiving()
+			peer.timersAnyAuthenticatedPacketTraversal()
+			peer.timersAnyAuthenticatedPacketReceived()
+		}
+		if dataPacketReceived {
+			peer.timersDataReceived()
 		}
 		if len(bufs) > 0 {
 			_, err := device.tun.device.Write(bufs, MessageTransportOffsetContent)
@@ -515,11 +587,73 @@ func (peer *Peer) RoutineSequentialReceiver(maxBatchSize int) {
 				device.log.Errorf("Failed to write packets to TUN device: %v", err)
 			}
 		}
-		for _, elem := range *elems {
+		for _, elem := range elemsContainer.elems {
 			device.PutMessageBuffer(elem.buffer)
 			device.PutInboundElement(elem)
 		}
 		bufs = bufs[:0]
-		device.PutInboundElementsSlice(elems)
+		device.PutInboundElementsContainer(elemsContainer)
 	}
 }
+
+func applyHash(dst, src, hash []byte) {
+	for i := range len(dst) {
+		dst[i] = src[i] ^ hash[i]
+	}
+}
+
+func (device *Device) DeterminePacketTypeAndPadding(packet []byte, typeHash []byte) (int, uint32, uint32) {
+	var headerBytes [4]byte
+	var padding uint32
+	var header UintRange
+	var expectedSize int
+
+	size := len(packet)
+	randomTrailers := device.randomTrailers.Load()
+
+	padding = device.paddings.init.Load()
+	header = device.headers.init.Load()
+	expectedSize = int(padding) + MessageInitiationSize
+
+	if size == expectedSize || randomTrailers && size > expectedSize {
+		applyHash(headerBytes[:], packet[padding:padding+4], typeHash)
+		if header.Contains(binary.LittleEndian.Uint32(headerBytes[:])) {
+			return MessageInitiationSize, MessageInitiationType, padding
+		}
+	}
+
+	padding = device.paddings.response.Load()
+	header = device.headers.response.Load()
+	expectedSize = int(padding) + MessageResponseSize
+
+	if size == expectedSize || randomTrailers && size > expectedSize {
+		applyHash(headerBytes[:], packet[padding:padding+4], typeHash)
+		if header.Contains(binary.LittleEndian.Uint32(headerBytes[:])) {
+			return MessageResponseSize, MessageResponseType, padding
+		}
+	}
+
+	padding = device.paddings.cookie.Load()
+	header = device.headers.cookie.Load()
+	expectedSize = int(padding) + MessageCookieReplySize
+
+	if size == expectedSize || randomTrailers && size > expectedSize {
+		applyHash(headerBytes[:], packet[padding:padding+4], typeHash)
+		if header.Contains(binary.LittleEndian.Uint32(headerBytes[:])) {
+			return MessageCookieReplySize, MessageCookieReplyType, padding
+		}
+	}
+
+	padding = device.paddings.transport.Load()
+	header = device.headers.transport.Load()
+	expectedSize = int(padding) + MessageTransportSize
+
+	if size >= expectedSize {
+		applyHash(headerBytes[:], packet[padding:padding+4], typeHash)
+		if header.Contains(binary.LittleEndian.Uint32(headerBytes[:])) {
+			return MessageTransportSize, MessageTransportType, padding
+		}
+	}
+
+	return 0, MessageUnknownType, 0
+}

device/send.go

@@ -1,23 +1,26 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package device
 
 import (
 	"bytes"
+	"crypto/rand"
 	"encoding/binary"
 	"errors"
 	"net"
 	"os"
+	"slices"
 	"sync"
 	"time"
 
+	"github.com/amnezia-vpn/amneziawg-go/v3/conn"
+	"github.com/amnezia-vpn/amneziawg-go/v3/tun"
 	"golang.org/x/crypto/chacha20poly1305"
 	"golang.org/x/net/ipv4"
 	"golang.org/x/net/ipv6"
-	"golang.zx2c4.com/wireguard/tun"
 )
 
 /* Outbound flow
@@ -45,19 +48,26 @@ import (
  */
 
 type QueueOutboundElement struct {
+	buffer      *[MaxMessageSize]byte // slice holding the packet data
+	packet      []byte                // slice of "buffer" (always!)
+	nonce       uint64                // nonce for encryption
+	keypair     *Keypair              // keypair for encryption
+	peer        *Peer                 // related peer
+	padding     uint32
+	isKeepalive bool
+}
+
+type QueueOutboundElementsContainer struct {
 	sync.Mutex
-	buffer  *[MaxMessageSize]byte // slice holding the packet data
-	packet  []byte                // slice of "buffer" (always!)
-	nonce   uint64                // nonce for encryption
-	keypair *Keypair              // keypair for encryption
-	peer    *Peer                 // related peer
+	elems []*QueueOutboundElement
 }
 
 func (device *Device) NewOutboundElement() *QueueOutboundElement {
 	elem := device.GetOutboundElement()
 	elem.buffer = device.GetMessageBuffer()
-	elem.Mutex = sync.Mutex{}
 	elem.nonce = 0
+	elem.padding = device.paddings.transport.Load()
+	elem.isKeepalive = false
 	// keypair and peer were cleared (if necessary) by clearPointers.
 	return elem
 }
@@ -78,15 +88,16 @@ func (elem *QueueOutboundElement) clearPointers() {
 func (peer *Peer) SendKeepalive() {
 	if len(peer.queue.staged) == 0 && peer.isRunning.Load() {
 		elem := peer.device.NewOutboundElement()
-		elems := peer.device.GetOutboundElementsSlice()
-		*elems = append(*elems, elem)
+		elem.isKeepalive = true
+		elemsContainer := peer.device.GetOutboundElementsContainer()
+		elemsContainer.elems = append(elemsContainer.elems, elem)
 		select {
-		case peer.queue.staged <- elems:
+		case peer.queue.staged <- elemsContainer:
 			peer.device.log.Verbosef("%v - Sending keepalive packet", peer)
 		default:
 			peer.device.PutMessageBuffer(elem.buffer)
 			peer.device.PutOutboundElement(elem)
-			peer.device.PutOutboundElementsSlice(elems)
+			peer.device.PutOutboundElementsContainer(elemsContainer)
 		}
 	}
 	peer.SendStagedPackets()
@@ -95,17 +106,20 @@ func (peer *Peer) SendKeepalive() {
 func (peer *Peer) SendHandshakeInitiation(isRetry bool) error {
 	if !isRetry {
 		peer.timers.handshakeAttempts.Store(0)
+		peer.timers.maxHandshakeAttempts.Store(peer.device.maxHandshakeAttemps())
 	}
 
+	timeout := peer.device.rekeyMinTimeout()
+
 	peer.handshake.mutex.RLock()
-	if time.Since(peer.handshake.lastSentHandshake) < RekeyTimeout {
+	if time.Since(peer.handshake.lastSentHandshake) < timeout {
 		peer.handshake.mutex.RUnlock()
 		return nil
 	}
 	peer.handshake.mutex.RUnlock()
 
 	peer.handshake.mutex.Lock()
-	if time.Since(peer.handshake.lastSentHandshake) < RekeyTimeout {
+	if time.Since(peer.handshake.lastSentHandshake) < timeout {
 		peer.handshake.mutex.Unlock()
 		return nil
 	}
@@ -120,8 +134,27 @@ func (peer *Peer) SendHandshakeInitiation(isRetry bool) error {
 		return err
 	}
 
-	var buf [MessageInitiationSize]byte
-	writer := bytes.NewBuffer(buf[:0])
+	var sendBuffer [][]byte
+
+	for _, ipacket := range peer.device.ipackets {
+		if ipacket != nil {
+			buf := make([]byte, ipacket.ObfuscatedLen(0))
+			ipacket.Obfuscate(buf, nil)
+			sendBuffer = append(sendBuffer, buf)
+		}
+	}
+
+	sendBuffer = append(sendBuffer, peer.device.JunkPackets()...)
+
+	padding := int(peer.device.paddings.init.Load())
+	trailerLen := max(peer.randomTrailer(padding+MessageInitiationSize), 0)
+
+	buf := make([]byte, padding+MessageInitiationSize+trailerLen)
+
+	crypt := buf[:padding]
+	rand.Read(crypt)
+
+	writer := bytes.NewBuffer(buf[padding:padding])
 	binary.Write(writer, binary.LittleEndian, msg)
 	packet := writer.Bytes()
 	peer.cookieGenerator.AddMacs(packet)
@@ -129,7 +162,19 @@ func (peer *Peer) SendHandshakeInitiation(isRetry bool) error {
 	peer.timersAnyAuthenticatedPacketTraversal()
 	peer.timersAnyAuthenticatedPacketSent()
 
-	err = peer.SendBuffers([][]byte{packet})
+	cip, err := peer.device.HeaderProtectionCipher(crypt[:HeaderCipherNonceSize])
+	if err != nil {
+		return err
+	}
+	if cip != nil {
+		cip.XORKeyStream(packet, packet)
+	}
+
+	trailer := buf[padding+MessageInitiationSize:]
+	rand.Read(trailer)
+
+	sendBuffer = append(sendBuffer, buf)
+	err = peer.SendBuffers(sendBuffer)
 	if err != nil {
 		peer.device.log.Errorf("%v - Failed to send handshake initiation: %v", peer, err)
 	}
@@ -151,8 +196,15 @@ func (peer *Peer) SendHandshakeResponse() error {
 		return err
 	}
 
-	var buf [MessageResponseSize]byte
-	writer := bytes.NewBuffer(buf[:0])
+	padding := int(peer.device.paddings.response.Load())
+	trailerLen := max(peer.randomTrailer(padding+MessageResponseSize), 0)
+
+	buf := make([]byte, padding+MessageResponseSize+trailerLen)
+
+	crypt := buf[:padding]
+	rand.Read(crypt)
+
+	writer := bytes.NewBuffer(buf[padding:padding])
 	binary.Write(writer, binary.LittleEndian, response)
 	packet := writer.Bytes()
 	peer.cookieGenerator.AddMacs(packet)
@@ -167,8 +219,19 @@ func (peer *Peer) SendHandshakeResponse() error {
 	peer.timersAnyAuthenticatedPacketTraversal()
 	peer.timersAnyAuthenticatedPacketSent()
 
+	cip, err := peer.device.HeaderProtectionCipher(crypt[:HeaderCipherNonceSize])
+	if err != nil {
+		return err
+	}
+	if cip != nil {
+		cip.XORKeyStream(packet, packet)
+	}
+
+	trailer := buf[padding+MessageResponseSize:]
+	rand.Read(trailer)
+
 	// TODO: allocation could be avoided
-	err = peer.SendBuffers([][]byte{packet})
+	err = peer.SendBuffers([][]byte{buf})
 	if err != nil {
 		peer.device.log.Errorf("%v - Failed to send handshake response: %v", peer, err)
 	}
@@ -179,17 +242,44 @@ func (device *Device) SendHandshakeCookie(initiatingElem *QueueHandshakeElement)
 	device.log.Verbosef("Sending cookie response for denied handshake message for %v", initiatingElem.endpoint.DstToString())
 
 	sender := binary.LittleEndian.Uint32(initiatingElem.packet[4:8])
-	reply, err := device.cookieChecker.CreateReply(initiatingElem.packet, sender, initiatingElem.endpoint.DstToBytes())
+	msgType := device.headers.cookie.Load().PickOne()
+
+	reply, err := device.cookieChecker.CreateReply(
+		initiatingElem.packet,
+		sender,
+		initiatingElem.endpoint.DstToBytes(),
+		msgType,
+	)
 	if err != nil {
 		device.log.Errorf("Failed to create cookie reply: %v", err)
 		return err
 	}
 
-	var buf [MessageCookieReplySize]byte
-	writer := bytes.NewBuffer(buf[:0])
+	padding := int(device.paddings.cookie.Load())
+	trailerLen := max(device.randomTrailer(padding+MessageCookieReplySize), 0)
+
+	buf := make([]byte, padding+MessageCookieReplySize+trailerLen)
+
+	crypt := buf[:padding]
+	rand.Read(crypt)
+
+	writer := bytes.NewBuffer(buf[padding:padding])
 	binary.Write(writer, binary.LittleEndian, reply)
+	packet := writer.Bytes()
+
+	cip, err := device.HeaderProtectionCipher(crypt[:HeaderCipherNonceSize])
+	if err != nil {
+		return err
+	}
+	if cip != nil {
+		cip.XORKeyStream(packet, packet)
+	}
+
+	trailer := buf[padding+MessageCookieReplySize:]
+	rand.Read(trailer)
+
 	// TODO: allocation could be avoided
-	device.net.bind.Send([][]byte{writer.Bytes()}, initiatingElem.endpoint)
+	device.net.bind.Send([][]byte{buf}, initiatingElem.endpoint)
 	return nil
 }
 
@@ -199,7 +289,7 @@ func (peer *Peer) keepKeyFreshSending() {
 		return
 	}
 	nonce := keypair.sendNonce.Load()
-	if nonce > RekeyAfterMessages || (keypair.isInitiator && time.Since(keypair.created) > RekeyAfterTime) {
+	if nonce > RekeyAfterMessages || (keypair.isInitiator && time.Since(keypair.created) > peer.device.keyRefreshTimeoutSending()) {
 		peer.SendHandshakeInitiation(false)
 	}
 }
@@ -218,10 +308,9 @@ func (device *Device) RoutineReadFromTUN() {
 		readErr     error
 		elems       = make([]*QueueOutboundElement, batchSize)
 		bufs        = make([][]byte, batchSize)
-		elemsByPeer = make(map[*Peer]*[]*QueueOutboundElement, batchSize)
+		elemsByPeer = make(map[*Peer]*QueueOutboundElementsContainer, batchSize)
 		count       = 0
 		sizes       = make([]int, batchSize)
-		offset      = MessageTransportHeaderSize
 	)
 
 	for i := range elems {
@@ -239,6 +328,9 @@ func (device *Device) RoutineReadFromTUN() {
 	}()
 
 	for {
+		padding := device.paddings.transport.Load()
+		offset := MessageTransportHeaderSize + int(padding)
+
 		// read packets
 		count, readErr = device.tun.device.Read(bufs, sizes, offset)
 		for i := 0; i < count; i++ {
@@ -248,6 +340,7 @@ func (device *Device) RoutineReadFromTUN() {
 
 			elem := elems[i]
 			elem.packet = bufs[i][offset : offset+sizes[i]]
+			elem.padding = padding
 
 			// lookup peer
 			var peer *Peer
@@ -275,10 +368,10 @@ func (device *Device) RoutineReadFromTUN() {
 			}
 			elemsForPeer, ok := elemsByPeer[peer]
 			if !ok {
-				elemsForPeer = device.GetOutboundElementsSlice()
+				elemsForPeer = device.GetOutboundElementsContainer()
 				elemsByPeer[peer] = elemsForPeer
 			}
-			*elemsForPeer = append(*elemsForPeer, elem)
+			elemsForPeer.elems = append(elemsForPeer.elems, elem)
 			elems[i] = device.NewOutboundElement()
 			bufs[i] = elems[i].buffer[:]
 		}
@@ -288,11 +381,11 @@ func (device *Device) RoutineReadFromTUN() {
 				peer.StagePackets(elemsForPeer)
 				peer.SendStagedPackets()
 			} else {
-				for _, elem := range *elemsForPeer {
+				for _, elem := range elemsForPeer.elems {
 					device.PutMessageBuffer(elem.buffer)
 					device.PutOutboundElement(elem)
 				}
-				device.PutOutboundElementsSlice(elemsForPeer)
+				device.PutOutboundElementsContainer(elemsForPeer)
 			}
 			delete(elemsByPeer, peer)
 		}
@@ -316,7 +409,7 @@ func (device *Device) RoutineReadFromTUN() {
 	}
 }
 
-func (peer *Peer) StagePackets(elems *[]*QueueOutboundElement) {
+func (peer *Peer) StagePackets(elems *QueueOutboundElementsContainer) {
 	for {
 		select {
 		case peer.queue.staged <- elems:
@@ -325,11 +418,11 @@ func (peer *Peer) StagePackets(elems *[]*QueueOutboundElement) {
 		}
 		select {
 		case tooOld := <-peer.queue.staged:
-			for _, elem := range *tooOld {
+			for _, elem := range tooOld.elems {
 				peer.device.PutMessageBuffer(elem.buffer)
 				peer.device.PutOutboundElement(elem)
 			}
-			peer.device.PutOutboundElementsSlice(tooOld)
+			peer.device.PutOutboundElementsContainer(tooOld)
 		default:
 		}
 	}
@@ -342,60 +435,58 @@ top:
 	}
 
 	keypair := peer.keypairs.Current()
-	if keypair == nil || keypair.sendNonce.Load() >= RejectAfterMessages || time.Since(keypair.created) >= RejectAfterTime {
+	if keypair == nil || keypair.sendNonce.Load() >= RejectAfterMessages || time.Since(keypair.created) >= peer.device.keychainExpireTime() {
 		peer.SendHandshakeInitiation(false)
 		return
 	}
 
 	for {
-		var elemsOOO *[]*QueueOutboundElement
+		var elemsContainerOOO *QueueOutboundElementsContainer
 		select {
-		case elems := <-peer.queue.staged:
+		case elemsContainer := <-peer.queue.staged:
 			i := 0
-			for _, elem := range *elems {
+			for _, elem := range elemsContainer.elems {
 				elem.peer = peer
 				elem.nonce = keypair.sendNonce.Add(1) - 1
 				if elem.nonce >= RejectAfterMessages {
 					keypair.sendNonce.Store(RejectAfterMessages)
-					if elemsOOO == nil {
-						elemsOOO = peer.device.GetOutboundElementsSlice()
+					if elemsContainerOOO == nil {
+						elemsContainerOOO = peer.device.GetOutboundElementsContainer()
 					}
-					*elemsOOO = append(*elemsOOO, elem)
+					elemsContainerOOO.elems = append(elemsContainerOOO.elems, elem)
 					continue
 				} else {
-					(*elems)[i] = elem
+					elemsContainer.elems[i] = elem
 					i++
 				}
 
 				elem.keypair = keypair
-				elem.Lock()
 			}
-			*elems = (*elems)[:i]
+			elemsContainer.Lock()
+			elemsContainer.elems = elemsContainer.elems[:i]
 
-			if elemsOOO != nil {
-				peer.StagePackets(elemsOOO) // XXX: Out of order, but we can't front-load go chans
+			if elemsContainerOOO != nil {
+				peer.StagePackets(elemsContainerOOO) // XXX: Out of order, but we can't front-load go chans
 			}
 
-			if len(*elems) == 0 {
-				peer.device.PutOutboundElementsSlice(elems)
+			if len(elemsContainer.elems) == 0 {
+				peer.device.PutOutboundElementsContainer(elemsContainer)
 				goto top
 			}
 
 			// add to parallel and sequential queue
 			if peer.isRunning.Load() {
-				peer.queue.outbound.c <- elems
-				for _, elem := range *elems {
-					peer.device.queue.encryption.c <- elem
-				}
+				peer.queue.outbound.c <- elemsContainer
+				peer.device.queue.encryption.c <- elemsContainer
 			} else {
-				for _, elem := range *elems {
+				for _, elem := range elemsContainer.elems {
 					peer.device.PutMessageBuffer(elem.buffer)
 					peer.device.PutOutboundElement(elem)
 				}
-				peer.device.PutOutboundElementsSlice(elems)
+				peer.device.PutOutboundElementsContainer(elemsContainer)
 			}
 
-			if elemsOOO != nil {
+			if elemsContainerOOO != nil {
 				goto top
 			}
 		default:
@@ -407,12 +498,12 @@ top:
 func (peer *Peer) FlushStagedPackets() {
 	for {
 		select {
-		case elems := <-peer.queue.staged:
-			for _, elem := range *elems {
+		case elemsContainer := <-peer.queue.staged:
+			for _, elem := range elemsContainer.elems {
 				peer.device.PutMessageBuffer(elem.buffer)
 				peer.device.PutOutboundElement(elem)
 			}
-			peer.device.PutOutboundElementsSlice(elems)
+			peer.device.PutOutboundElementsContainer(elemsContainer)
 		default:
 			return
 		}
@@ -434,44 +525,121 @@ func calculatePaddingSize(packetSize, mtu int) int {
 	return paddedSize - lastUnit
 }
 
+func (peer *Peer) randomPaddingAddition(packetSize int) int {
+	addition := peer.device.contentPaddingAddition.Load()
+
+	if addition.IsZero() {
+		return -1
+	}
+
+	udpWindow := int(peer.udpWindow.Load())
+	if udpWindow < packetSize {
+		return 0
+	}
+
+	add := int(addition.PickOne())
+	space := udpWindow - packetSize
+	if add > space {
+		add = space
+	}
+	return add
+}
+
+func (device *Device) randomTrailer(packetSize int) int {
+	if !device.randomTrailers.Load() {
+		return -1
+	}
+
+	if DefaultUdpWindow < packetSize {
+		return 0
+	}
+	return int(fastrandn(uint32(DefaultUdpWindow - packetSize)))
+}
+
+func (peer *Peer) randomTrailer(packetSize int) int {
+	if !peer.device.randomTrailers.Load() {
+		return -1
+	}
+
+	udpWindow := int(peer.udpWindow.Load())
+	if udpWindow < packetSize {
+		return 0
+	}
+	return int(fastrandn(uint32(udpWindow - packetSize)))
+}
+
 /* Encrypts the elements in the queue
  * and marks them for sequential consumption (by releasing the mutex)
  *
  * Obs. One instance per core
  */
 func (device *Device) RoutineEncryption(id int) {
-	var paddingZeros [PaddingMultiple]byte
 	var nonce [chacha20poly1305.NonceSize]byte
 
 	defer device.log.Verbosef("Routine: encryption worker %d - stopped", id)
 	device.log.Verbosef("Routine: encryption worker %d - started", id)
 
-	for elem := range device.queue.encryption.c {
-		// populate header fields
-		header := elem.buffer[:MessageTransportHeaderSize]
+	for elemsContainer := range device.queue.encryption.c {
+		for _, elem := range elemsContainer.elems {
+			udpWindow := elem.padding + MinMessageSize + uint32(len(elem.packet))
+			if elem.peer.udpWindow.Load() < udpWindow {
+				elem.peer.udpWindow.Store(udpWindow)
+			}
 
-		fieldType := header[0:4]
-		fieldReceiver := header[4:8]
-		fieldNonce := header[8:16]
+			// fill crypto padding
+			crypt := elem.buffer[:elem.padding]
+			rand.Read(crypt)
 
-		binary.LittleEndian.PutUint32(fieldType, MessageTransportType)
-		binary.LittleEndian.PutUint32(fieldReceiver, elem.keypair.remoteIndex)
-		binary.LittleEndian.PutUint64(fieldNonce, elem.nonce)
+			// populate header fields
+			header := elem.buffer[elem.padding : elem.padding+MessageTransportHeaderSize]
 
-		// pad content to multiple of 16
-		paddingSize := calculatePaddingSize(len(elem.packet), int(device.tun.mtu.Load()))
-		elem.packet = append(elem.packet, paddingZeros[:paddingSize]...)
+			fieldType := header[0:4]
+			fieldReceiver := header[4:8]
+			fieldNonce := header[8:16]
 
-		// encrypt content and release to consumer
+			binary.LittleEndian.PutUint32(fieldType, device.headers.transport.Load().PickOne())
+			binary.LittleEndian.PutUint32(fieldReceiver, elem.keypair.remoteIndex)
+			binary.LittleEndian.PutUint64(fieldNonce, elem.nonce)
 
-		binary.LittleEndian.PutUint64(nonce[4:], elem.nonce)
-		elem.packet = elem.keypair.send.Seal(
-			header,
-			nonce[:],
-			elem.packet,
-			nil,
-		)
-		elem.Unlock()
+			packetSize := len(elem.packet) + MinMessageSize + int(elem.padding)
+			mtu := int(device.tun.mtu.Load())
+
+			paddingSize := elem.peer.randomPaddingAddition(packetSize)
+			if paddingSize < 0 {
+				paddingSize = elem.peer.randomTrailer(packetSize)
+			}
+			if paddingSize < 0 {
+				// pad content to multiple of 16
+				paddingSize = calculatePaddingSize(len(elem.packet), mtu)
+			}
+
+			// append trailing zeroes
+			oldLen := len(elem.packet)
+			elem.packet = slices.Grow(elem.packet, paddingSize)
+			elem.packet = elem.packet[:oldLen+paddingSize]
+			clear(elem.packet[oldLen:])
+
+			// encrypt content and release to consumer
+
+			binary.LittleEndian.PutUint64(nonce[4:], elem.nonce)
+			elem.packet = elem.keypair.send.Seal(
+				elem.buffer[:elem.padding+MessageTransportHeaderSize],
+				nonce[:],
+				elem.packet,
+				nil,
+			)
+
+			cip, err := device.HeaderProtectionCipher(crypt[:HeaderCipherNonceSize])
+			if err != nil {
+				device.log.Errorf("Routing: header obfuscation failed - packet dropped")
+				elem.packet = nil
+				continue
+			}
+			if cip != nil {
+				cip.XORKeyStream(header, header)
+			}
+		}
+		elemsContainer.Unlock()
 	}
 }
 
@@ -485,9 +653,9 @@ func (peer *Peer) RoutineSequentialSender(maxBatchSize int) {
 
 	bufs := make([][]byte, 0, maxBatchSize)
 
-	for elems := range peer.queue.outbound.c {
+	for elemsContainer := range peer.queue.outbound.c {
 		bufs = bufs[:0]
-		if elems == nil {
+		if elemsContainer == nil {
 			return
 		}
 		if !peer.isRunning.Load() {
@@ -497,19 +665,21 @@ func (peer *Peer) RoutineSequentialSender(maxBatchSize int) {
 			// The timers and SendBuffers code are resilient to a few stragglers.
 			// TODO: rework peer shutdown order to ensure
 			// that we never accidentally keep timers alive longer than necessary.
-			for _, elem := range *elems {
-				elem.Lock()
+			elemsContainer.Lock()
+			for _, elem := range elemsContainer.elems {
 				device.PutMessageBuffer(elem.buffer)
 				device.PutOutboundElement(elem)
 			}
+			device.PutOutboundElementsContainer(elemsContainer)
 			continue
 		}
 		dataSent := false
-		for _, elem := range *elems {
-			elem.Lock()
-			if len(elem.packet) != MessageKeepaliveSize {
+		elemsContainer.Lock()
+		for _, elem := range elemsContainer.elems {
+			if !elem.isKeepalive {
 				dataSent = true
 			}
+
 			bufs = append(bufs, elem.packet)
 		}
 
@@ -520,11 +690,19 @@ func (peer *Peer) RoutineSequentialSender(maxBatchSize int) {
 		if dataSent {
 			peer.timersDataSent()
 		}
-		for _, elem := range *elems {
+
+		for _, elem := range elemsContainer.elems {
 			device.PutMessageBuffer(elem.buffer)
 			device.PutOutboundElement(elem)
 		}
-		device.PutOutboundElementsSlice(elems)
+		device.PutOutboundElementsContainer(elemsContainer)
+		if err != nil {
+			var errGSO conn.ErrUDPGSODisabled
+			if errors.As(err, &errGSO) {
+				device.log.Verbosef(err.Error())
+				err = errGSO.RetryErr
+			}
+		}
 		if err != nil {
 			device.log.Errorf("%v - Failed to send data packets: %v", peer, err)
 			continue

device/sticky_default.go

@@ -3,10 +3,10 @@
 package device
 
 import (
-	"golang.zx2c4.com/wireguard/conn"
-	"golang.zx2c4.com/wireguard/rwcancel"
+	"github.com/amnezia-vpn/amneziawg-go/v3/conn"
+	"github.com/amnezia-vpn/amneziawg-go/v3/rwcancel"
 )
 
-func (device *Device) startRouteListener(bind conn.Bind) (*rwcancel.RWCancel, error) {
+func (device *Device) startRouteListener(_ conn.Bind) (*rwcancel.RWCancel, error) {
 	return nil, nil
 }

device/sticky_linux.go

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  *
  * This implements userspace semantics of "sticky sockets", modeled after
  * WireGuard's kernelspace implementation. This is more or less a straight port
@@ -9,7 +9,7 @@
  *
  * Currently there is no way to achieve this within the net package:
  * See e.g. https://github.com/golang/go/issues/17930
- * So this code is remains platform dependent.
+ * So this code remains platform dependent.
  */
 
 package device
@@ -20,8 +20,8 @@ import (
 
 	"golang.org/x/sys/unix"
 
-	"golang.zx2c4.com/wireguard/conn"
-	"golang.zx2c4.com/wireguard/rwcancel"
+	"github.com/amnezia-vpn/amneziawg-go/v3/conn"
+	"github.com/amnezia-vpn/amneziawg-go/v3/rwcancel"
 )
 
 func (device *Device) startRouteListener(bind conn.Bind) (*rwcancel.RWCancel, error) {
@@ -47,7 +47,7 @@ func (device *Device) startRouteListener(bind conn.Bind) (*rwcancel.RWCancel, er
 	return netlinkCancel, nil
 }
 
-func (device *Device) routineRouteListener(bind conn.Bind, netlinkSock int, netlinkCancel *rwcancel.RWCancel) {
+func (device *Device) routineRouteListener(_ conn.Bind, netlinkSock int, netlinkCancel *rwcancel.RWCancel) {
 	type peerEndpointPtr struct {
 		peer     *Peer
 		endpoint *conn.Endpoint
@@ -110,17 +110,17 @@ func (device *Device) routineRouteListener(bind conn.Bind, netlinkSock int, netl
 								if !ok {
 									break
 								}
-								pePtr.peer.Lock()
-								if &pePtr.peer.endpoint != pePtr.endpoint {
-									pePtr.peer.Unlock()
+								pePtr.peer.endpoint.Lock()
+								if &pePtr.peer.endpoint.val != pePtr.endpoint {
+									pePtr.peer.endpoint.Unlock()
 									break
 								}
-								if uint32(pePtr.peer.endpoint.(*conn.StdNetEndpoint).SrcIfidx()) == ifidx {
-									pePtr.peer.Unlock()
+								if uint32(pePtr.peer.endpoint.val.(*conn.StdNetEndpoint).SrcIfidx()) == ifidx {
+									pePtr.peer.endpoint.Unlock()
 									break
 								}
-								pePtr.peer.endpoint.(*conn.StdNetEndpoint).ClearSrc()
-								pePtr.peer.Unlock()
+								pePtr.peer.endpoint.clearSrcOnTx = true
+								pePtr.peer.endpoint.Unlock()
 							}
 							attr = attr[attrhdr.Len:]
 						}
@@ -134,18 +134,18 @@ func (device *Device) routineRouteListener(bind conn.Bind, netlinkSock int, netl
 					device.peers.RLock()
 					i := uint32(1)
 					for _, peer := range device.peers.keyMap {
-						peer.RLock()
-						if peer.endpoint == nil {
-							peer.RUnlock()
+						peer.endpoint.Lock()
+						if peer.endpoint.val == nil {
+							peer.endpoint.Unlock()
 							continue
 						}
-						nativeEP, _ := peer.endpoint.(*conn.StdNetEndpoint)
+						nativeEP, _ := peer.endpoint.val.(*conn.StdNetEndpoint)
 						if nativeEP == nil {
-							peer.RUnlock()
+							peer.endpoint.Unlock()
 							continue
 						}
 						if nativeEP.DstIP().Is6() || nativeEP.SrcIfidx() == 0 {
-							peer.RUnlock()
+							peer.endpoint.Unlock()
 							break
 						}
 						nlmsg := struct {
@@ -188,10 +188,10 @@ func (device *Device) routineRouteListener(bind conn.Bind, netlinkSock int, netl
 						reqPeerLock.Lock()
 						reqPeer[i] = peerEndpointPtr{
 							peer:     peer,
-							endpoint: &peer.endpoint,
+							endpoint: &peer.endpoint.val,
 						}
 						reqPeerLock.Unlock()
-						peer.RUnlock()
+						peer.endpoint.Unlock()
 						i++
 						_, err := netlinkCancel.Write((*[unsafe.Sizeof(nlmsg)]byte)(unsafe.Pointer(&nlmsg))[:])
 						if err != nil {

device/timers.go

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  *
  * This is based heavily on timers.c from the kernel implementation.
  */
@@ -22,24 +22,25 @@ type Timer struct {
 	*time.Timer
 	modifyingLock sync.RWMutex
 	runningLock   sync.Mutex
-	isPending     bool
+	duration      time.Duration
 }
 
-func (peer *Peer) NewTimer(expirationFunction func(*Peer)) *Timer {
+func (peer *Peer) NewTimer(expirationFunction func(*Peer, time.Duration)) *Timer {
 	timer := &Timer{}
 	timer.Timer = time.AfterFunc(time.Hour, func() {
 		timer.runningLock.Lock()
 		defer timer.runningLock.Unlock()
 
 		timer.modifyingLock.Lock()
-		if !timer.isPending {
+		if timer.duration == 0 {
 			timer.modifyingLock.Unlock()
 			return
 		}
-		timer.isPending = false
+		duration := timer.duration
 		timer.modifyingLock.Unlock()
+		timer.duration = 0
 
-		expirationFunction(peer)
+		expirationFunction(peer, duration)
 	})
 	timer.Stop()
 	return timer
@@ -47,14 +48,14 @@ func (peer *Peer) NewTimer(expirationFunction func(*Peer)) *Timer {
 
 func (timer *Timer) Mod(d time.Duration) {
 	timer.modifyingLock.Lock()
-	timer.isPending = true
+	timer.duration = d
 	timer.Reset(d)
 	timer.modifyingLock.Unlock()
 }
 
 func (timer *Timer) Del() {
 	timer.modifyingLock.Lock()
-	timer.isPending = false
+	timer.duration = 0
 	timer.Stop()
 	timer.modifyingLock.Unlock()
 }
@@ -69,16 +70,18 @@ func (timer *Timer) DelSync() {
 func (timer *Timer) IsPending() bool {
 	timer.modifyingLock.RLock()
 	defer timer.modifyingLock.RUnlock()
-	return timer.isPending
+	return timer.duration > 0
 }
 
 func (peer *Peer) timersActive() bool {
 	return peer.isRunning.Load() && peer.device != nil && peer.device.isUp()
 }
 
-func expiredRetransmitHandshake(peer *Peer) {
-	if peer.timers.handshakeAttempts.Load() > MaxTimerHandshakes {
-		peer.device.log.Verbosef("%s - Handshake did not complete after %d attempts, giving up", peer, MaxTimerHandshakes+2)
+func expiredRetransmitHandshake(peer *Peer, d time.Duration) {
+	maxAttempts := peer.timers.maxHandshakeAttempts.Load()
+
+	if peer.timers.handshakeAttempts.Load() > maxAttempts {
+		peer.device.log.Verbosef("%s - Handshake did not complete after %d attempts, giving up", peer, maxAttempts+2)
 
 		if peer.timersActive() {
 			peer.timers.sendKeepalive.Del()
@@ -93,51 +96,43 @@ func expiredRetransmitHandshake(peer *Peer) {
 		 * of a partial exchange.
 		 */
 		if peer.timersActive() && !peer.timers.zeroKeyMaterial.IsPending() {
-			peer.timers.zeroKeyMaterial.Mod(RejectAfterTime * 3)
+			peer.timers.zeroKeyMaterial.Mod(peer.device.keychainExpireTime() * 3)
 		}
 	} else {
 		peer.timers.handshakeAttempts.Add(1)
-		peer.device.log.Verbosef("%s - Handshake did not complete after %d seconds, retrying (try %d)", peer, int(RekeyTimeout.Seconds()), peer.timers.handshakeAttempts.Load()+1)
+		peer.device.log.Verbosef("%s - Handshake did not complete after %d seconds, retrying (try %d)", peer, int(d.Seconds()), peer.timers.handshakeAttempts.Load()+1)
 
 		/* We clear the endpoint address src address, in case this is the cause of trouble. */
-		peer.Lock()
-		if peer.endpoint != nil {
-			peer.endpoint.ClearSrc()
-		}
-		peer.Unlock()
+		peer.markEndpointSrcForClearing()
 
 		peer.SendHandshakeInitiation(true)
 	}
 }
 
-func expiredSendKeepalive(peer *Peer) {
+func expiredSendKeepalive(peer *Peer, d time.Duration) {
 	peer.SendKeepalive()
 	if peer.timers.needAnotherKeepalive.Load() {
 		peer.timers.needAnotherKeepalive.Store(false)
 		if peer.timersActive() {
-			peer.timers.sendKeepalive.Mod(KeepaliveTimeout)
+			peer.timers.sendKeepalive.Mod(peer.sendKeepaliveTimeout())
 		}
 	}
 }
 
-func expiredNewHandshake(peer *Peer) {
-	peer.device.log.Verbosef("%s - Retrying handshake because we stopped hearing back after %d seconds", peer, int((KeepaliveTimeout + RekeyTimeout).Seconds()))
+func expiredNewHandshake(peer *Peer, d time.Duration) {
+	peer.device.log.Verbosef("%s - Retrying handshake because we stopped hearing back after %d seconds", peer, int(d.Seconds()))
 	/* We clear the endpoint address src address, in case this is the cause of trouble. */
-	peer.Lock()
-	if peer.endpoint != nil {
-		peer.endpoint.ClearSrc()
-	}
-	peer.Unlock()
+	peer.markEndpointSrcForClearing()
 	peer.SendHandshakeInitiation(false)
 }
 
-func expiredZeroKeyMaterial(peer *Peer) {
-	peer.device.log.Verbosef("%s - Removing all keys, since we haven't received a new one in %d seconds", peer, int((RejectAfterTime * 3).Seconds()))
+func expiredZeroKeyMaterial(peer *Peer, d time.Duration) {
+	peer.device.log.Verbosef("%s - Removing all keys, since we haven't received a new one in %d seconds", peer, int(d.Seconds()))
 	peer.ZeroAndFlushAll()
 }
 
-func expiredPersistentKeepalive(peer *Peer) {
-	if peer.persistentKeepaliveInterval.Load() > 0 {
+func expiredPersistentKeepalive(peer *Peer, d time.Duration) {
+	if !peer.persistentKeepaliveInterval.Load().IsZero() {
 		peer.SendKeepalive()
 	}
 }
@@ -145,7 +140,7 @@ func expiredPersistentKeepalive(peer *Peer) {
 /* Should be called after an authenticated data packet is sent. */
 func (peer *Peer) timersDataSent() {
 	if peer.timersActive() && !peer.timers.newHandshake.IsPending() {
-		peer.timers.newHandshake.Mod(KeepaliveTimeout + RekeyTimeout + time.Millisecond*time.Duration(fastrandn(RekeyTimeoutJitterMaxMs)))
+		peer.timers.newHandshake.Mod(peer.newHandshakeTimeout() + time.Millisecond*time.Duration(fastrandn(RekeyTimeoutJitterMaxMs)))
 	}
 }
 
@@ -153,7 +148,7 @@ func (peer *Peer) timersDataSent() {
 func (peer *Peer) timersDataReceived() {
 	if peer.timersActive() {
 		if !peer.timers.sendKeepalive.IsPending() {
-			peer.timers.sendKeepalive.Mod(KeepaliveTimeout)
+			peer.timers.sendKeepalive.Mod(peer.sendKeepaliveTimeout())
 		} else {
 			peer.timers.needAnotherKeepalive.Store(true)
 		}
@@ -177,7 +172,7 @@ func (peer *Peer) timersAnyAuthenticatedPacketReceived() {
 /* Should be called after a handshake initiation message is sent. */
 func (peer *Peer) timersHandshakeInitiated() {
 	if peer.timersActive() {
-		peer.timers.retransmitHandshake.Mod(RekeyTimeout + time.Millisecond*time.Duration(fastrandn(RekeyTimeoutJitterMaxMs)))
+		peer.timers.retransmitHandshake.Mod(peer.retransmitHandshakeTimeout() + time.Millisecond*time.Duration(fastrandn(RekeyTimeoutJitterMaxMs)))
 	}
 }
 
@@ -187,6 +182,7 @@ func (peer *Peer) timersHandshakeComplete() {
 		peer.timers.retransmitHandshake.Del()
 	}
 	peer.timers.handshakeAttempts.Store(0)
+	peer.timers.maxHandshakeAttempts.Store(peer.device.maxHandshakeAttemps())
 	peer.timers.sentLastMinuteHandshake.Store(false)
 	peer.lastHandshakeNano.Store(time.Now().UnixNano())
 }
@@ -194,15 +190,15 @@ func (peer *Peer) timersHandshakeComplete() {
 /* Should be called after an ephemeral key is created, which is before sending a handshake response or after receiving a handshake response. */
 func (peer *Peer) timersSessionDerived() {
 	if peer.timersActive() {
-		peer.timers.zeroKeyMaterial.Mod(RejectAfterTime * 3)
+		peer.timers.zeroKeyMaterial.Mod(peer.device.keychainExpireTime() * 3)
 	}
 }
 
 /* Should be called before a packet with authentication -- keepalive, data, or handshake -- is sent, or after one is received. */
 func (peer *Peer) timersAnyAuthenticatedPacketTraversal() {
 	keepalive := peer.persistentKeepaliveInterval.Load()
-	if keepalive > 0 && peer.timersActive() {
-		peer.timers.persistentKeepalive.Mod(time.Duration(keepalive) * time.Second)
+	if !keepalive.IsZero() && peer.timersActive() {
+		peer.timers.persistentKeepalive.Mod(time.Duration(keepalive.PickOne()) * time.Second)
 	}
 }
 
@@ -216,6 +212,7 @@ func (peer *Peer) timersInit() {
 
 func (peer *Peer) timersStart() {
 	peer.timers.handshakeAttempts.Store(0)
+	peer.timers.maxHandshakeAttempts.Store(peer.device.maxHandshakeAttemps())
 	peer.timers.sentLastMinuteHandshake.Store(false)
 	peer.timers.needAnotherKeepalive.Store(false)
 }
@@ -227,3 +224,95 @@ func (peer *Peer) timersStop() {
 	peer.timers.zeroKeyMaterial.DelSync()
 	peer.timers.persistentKeepalive.DelSync()
 }
+
+func (peer *Peer) retransmitHandshakeTimeout() time.Duration {
+	timeout := RekeyTimeout
+
+	if t := peer.device.timings.rekeyTimeoutSec.Load(); !t.IsZero() {
+		timeout = time.Duration(t.PickOne()) * time.Second
+	}
+
+	return timeout
+}
+
+func (peer *Peer) sendKeepaliveTimeout() time.Duration {
+	timeout := KeepaliveTimeout
+
+	if t := peer.device.timings.keepaliveTimeoutSec.Load(); !t.IsZero() {
+		timeout = time.Duration(t.PickOne()) * time.Second
+	}
+
+	return timeout
+}
+
+func (peer *Peer) newHandshakeTimeout() time.Duration {
+	keepaliveTimeout := KeepaliveTimeout
+	rekeyTimeout := RekeyTimeout
+
+	if t := peer.device.timings.keepaliveTimeoutSec.Load(); !t.IsZero() {
+		keepaliveTimeout = time.Duration(t.Hi()) * time.Second
+	}
+	if t := peer.device.timings.rekeyTimeoutSec.Load(); !t.IsZero() {
+		rekeyTimeout = time.Duration(t.PickOne()) * time.Second
+	}
+
+	return keepaliveTimeout + rekeyTimeout
+}
+
+func (device *Device) keyRefreshTimeoutSending() time.Duration {
+	rekeyAfterTime := RekeyAfterTime
+
+	if t := device.timings.rekeyAfterTimeSec.Load(); !t.IsZero() {
+		rekeyAfterTime = time.Duration(t.PickOne()) * time.Second
+	}
+
+	return rekeyAfterTime
+}
+
+func (device *Device) keyRefreshTimeoutReceiving() time.Duration {
+	rejectAfterTime := RejectAfterTime
+	keepaliveTimeout := KeepaliveTimeout
+	rekeyTimeout := RekeyTimeout
+
+	if t := device.timings.rejectAfterTimeSec.Load(); !t.IsZero() {
+		rejectAfterTime = time.Duration(t.PickOne()) * time.Second
+	}
+	if t := device.timings.keepaliveTimeoutSec.Load(); !t.IsZero() {
+		keepaliveTimeout = time.Duration(t.Lo()) * time.Second
+	}
+	if t := device.timings.rekeyTimeoutSec.Load(); !t.IsZero() {
+		rekeyTimeout = time.Duration(t.Lo()) * time.Second
+	}
+
+	return max(0, rejectAfterTime-keepaliveTimeout-rekeyTimeout)
+}
+
+func (device *Device) keychainExpireTime() time.Duration {
+	rejectAfterTime := RejectAfterTime
+
+	if t := device.timings.rejectAfterTimeSec.Load(); !t.IsZero() {
+		rejectAfterTime = time.Duration(t.Hi()) * time.Second
+	}
+
+	return rejectAfterTime
+}
+
+func (device *Device) rekeyMinTimeout() time.Duration {
+	rekeyTimeout := RekeyTimeout
+
+	if t := device.timings.rekeyTimeoutSec.Load(); !t.IsZero() {
+		rekeyTimeout = time.Duration(t.Lo()) * time.Second
+	}
+
+	return rekeyTimeout
+}
+
+func (device *Device) maxHandshakeAttemps() uint32 {
+	res := uint32(MaxTimerHandshakes)
+
+	if t := device.timings.maxHandshakeAttemps.Load(); !t.IsZero() {
+		res = t.PickOne()
+	}
+
+	return res
+}

device/tun.go

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package device
@@ -8,7 +8,7 @@ package device
 import (
 	"fmt"
 
-	"golang.zx2c4.com/wireguard/tun"
+	"github.com/amnezia-vpn/amneziawg-go/v3/tun"
 )
 
 const DefaultMTU = 1420

device/uapi.go

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package device
@@ -18,7 +18,7 @@ import (
 	"sync"
 	"time"
 
-	"golang.zx2c4.com/wireguard/ipc"
+	"github.com/amnezia-vpn/amneziawg-go/v3/ipc"
 )
 
 type IPCError struct {
@@ -70,6 +70,18 @@ func (device *Device) IpcGetOperation(w io.Writer) error {
 		}
 		buf.WriteByte('\n')
 	}
+	boolf := func(prefix string, val bool) {
+		buf.Grow(3 + len(prefix))
+		buf.WriteString(prefix)
+		buf.WriteByte('=')
+		if val {
+			buf.WriteByte('1')
+		} else {
+			buf.WriteByte('0')
+		}
+		buf.WriteByte('\n')
+
+	}
 
 	func() {
 		// lock required resources
@@ -83,6 +95,9 @@ func (device *Device) IpcGetOperation(w io.Writer) error {
 		device.peers.RLock()
 		defer device.peers.RUnlock()
 
+		device.headerProtection.RLock()
+		defer device.headerProtection.RUnlock()
+
 		// serialize device related values
 
 		if !device.staticIdentity.privateKey.IsZero() {
@@ -97,35 +112,112 @@ func (device *Device) IpcGetOperation(w io.Writer) error {
 			sendf("fwmark=%d", device.net.fwmark)
 		}
 
+		if count := device.junk.count.Load(); count != 0 {
+			sendf("jc=%d", count)
+		}
+
+		if min := device.junk.min.Load(); min != 0 {
+			sendf("jmin=%d", min)
+		}
+
+		if max := device.junk.max.Load(); max != 0 {
+			sendf("jmax=%d", max)
+		}
+
+		if padding := device.paddings.init.Load(); padding != 0 {
+			sendf("s1=%d", padding)
+		}
+
+		if padding := device.paddings.response.Load(); padding != 0 {
+			sendf("s2=%d", padding)
+		}
+
+		if padding := device.paddings.cookie.Load(); padding != 0 {
+			sendf("s3=%d", padding)
+		}
+
+		if padding := device.paddings.transport.Load(); padding != 0 {
+			sendf("s4=%d", padding)
+		}
+
+		if header := device.headers.init.Load(); !header.IsZero() {
+			sendf("h1=%s", header.ToString())
+		}
+
+		if header := device.headers.response.Load(); !header.IsZero() {
+			sendf("h2=%s", header.ToString())
+		}
+
+		if header := device.headers.cookie.Load(); !header.IsZero() {
+			sendf("h3=%s", header.ToString())
+		}
+
+		if header := device.headers.transport.Load(); !header.IsZero() {
+			sendf("h4=%s", header.ToString())
+		}
+
+		for i, ipacket := range device.ipackets {
+			if ipacket != nil {
+				sendf("i%d=%s", i+1, ipacket.Spec)
+			}
+		}
+
+		if !device.headerProtection.key.IsZero() {
+			keyf("header_protection_key", (*[32]byte)(&device.headerProtection.key))
+		}
+
+		if addition := device.contentPaddingAddition.Load(); !addition.IsZero() {
+			sendf("content_padding_addition=%s", addition.ToString())
+		}
+
+		if timing := device.timings.rekeyAfterTimeSec.Load(); !timing.IsZero() {
+			sendf("rekey_after_time=%s", timing.ToString())
+		}
+		if timing := device.timings.rekeyTimeoutSec.Load(); !timing.IsZero() {
+			sendf("rekey_timeout=%s", timing.ToString())
+		}
+		if timing := device.timings.rejectAfterTimeSec.Load(); !timing.IsZero() {
+			sendf("reject_after_time=%s", timing.ToString())
+		}
+		if timing := device.timings.keepaliveTimeoutSec.Load(); !timing.IsZero() {
+			sendf("keepalive_timeout=%s", timing.ToString())
+		}
+		if rang := device.timings.maxHandshakeAttemps.Load(); !rang.IsZero() {
+			sendf("max_handshake_attempts=%s", rang.ToString())
+		}
+		boolf("random_trailers", device.randomTrailers.Load())
+		boolf("disable_cookies", device.disableCookies.Load())
+
 		for _, peer := range device.peers.keyMap {
 			// Serialize peer state.
-			// Do the work in an anonymous function so that we can use defer.
-			func() {
-				peer.RLock()
-				defer peer.RUnlock()
+			peer.handshake.mutex.RLock()
+			keyf("public_key", (*[32]byte)(&peer.handshake.remoteStatic))
+			keyf("preshared_key", (*[32]byte)(&peer.handshake.presharedKey))
+			peer.handshake.mutex.RUnlock()
+			sendf("protocol_version=1")
+			peer.endpoint.Lock()
+			if peer.endpoint.val != nil {
+				sendf("endpoint=%s", peer.endpoint.val.DstToString())
+			}
+			peer.endpoint.Unlock()
 
-				keyf("public_key", (*[32]byte)(&peer.handshake.remoteStatic))
-				keyf("preshared_key", (*[32]byte)(&peer.handshake.presharedKey))
-				sendf("protocol_version=1")
-				if peer.endpoint != nil {
-					sendf("endpoint=%s", peer.endpoint.DstToString())
-				}
+			nano := peer.lastHandshakeNano.Load()
+			secs := nano / time.Second.Nanoseconds()
+			nano %= time.Second.Nanoseconds()
 
-				nano := peer.lastHandshakeNano.Load()
-				secs := nano / time.Second.Nanoseconds()
-				nano %= time.Second.Nanoseconds()
+			sendf("last_handshake_time_sec=%d", secs)
+			sendf("last_handshake_time_nsec=%d", nano)
+			sendf("tx_bytes=%d", peer.txBytes.Load())
+			sendf("rx_bytes=%d", peer.rxBytes.Load())
 
-				sendf("last_handshake_time_sec=%d", secs)
-				sendf("last_handshake_time_nsec=%d", nano)
-				sendf("tx_bytes=%d", peer.txBytes.Load())
-				sendf("rx_bytes=%d", peer.rxBytes.Load())
-				sendf("persistent_keepalive_interval=%d", peer.persistentKeepaliveInterval.Load())
+			if keepalive := peer.persistentKeepaliveInterval.Load(); !keepalive.IsZero() {
+				sendf("persistent_keepalive_interval=%s", keepalive.ToString())
+			}
 
-				device.allowedips.EntriesForPeer(peer, func(prefix netip.Prefix) bool {
-					sendf("allowed_ip=%s", prefix.String())
-					return true
-				})
-			}()
+			device.allowedips.EntriesForPeer(peer, func(prefix netip.Prefix) bool {
+				sendf("allowed_ip=%s", prefix.String())
+				return true
+			})
 		}
 	}()
 
@@ -149,6 +241,8 @@ func (device *Device) IpcSetOperation(r io.Reader) (err error) {
 		}
 	}()
 
+	ipcDev := new(ipcSetDevice)
+	ipcDev.fromDevice(device)
 	peer := new(ipcSetPeer)
 	deviceConfig := true
 
@@ -157,12 +251,20 @@ func (device *Device) IpcSetOperation(r io.Reader) (err error) {
 		line := scanner.Text()
 		if line == "" {
 			// Blank line means terminate operation.
+			err := ipcDev.mergeWithDevice(device)
+			if err != nil {
+				return ipcErrorf(ipc.IpcErrorInvalid, "failed to merge with device: %w", err)
+			}
 			peer.handlePostConfig()
 			return nil
 		}
 		key, value, ok := strings.Cut(line, "=")
 		if !ok {
-			return ipcErrorf(ipc.IpcErrorProtocol, "failed to parse line %q", line)
+			return ipcErrorf(
+				ipc.IpcErrorProtocol,
+				"failed to parse line %q",
+				line,
+			)
 		}
 
 		if key == "public_key" {
@@ -180,7 +282,7 @@ func (device *Device) IpcSetOperation(r io.Reader) (err error) {
 
 		var err error
 		if deviceConfig {
-			err = device.handleDeviceLine(key, value)
+			err = device.handleDeviceLine(ipcDev, key, value)
 		} else {
 			err = device.handlePeerLine(peer, key, value)
 		}
@@ -188,6 +290,10 @@ func (device *Device) IpcSetOperation(r io.Reader) (err error) {
 			return err
 		}
 	}
+	err = ipcDev.mergeWithDevice(device)
+	if err != nil {
+		return ipcErrorf(ipc.IpcErrorInvalid, "failed to merge with device: %w", err)
+	}
 	peer.handlePostConfig()
 
 	if err := scanner.Err(); err != nil {
@@ -196,7 +302,7 @@ func (device *Device) IpcSetOperation(r io.Reader) (err error) {
 	return nil
 }
 
-func (device *Device) handleDeviceLine(key, value string) error {
+func (device *Device) handleDeviceLine(ipcDev *ipcSetDevice, key, value string) error {
 	switch key {
 	case "private_key":
 		var sk NoisePrivateKey
@@ -237,11 +343,206 @@ func (device *Device) handleDeviceLine(key, value string) error {
 
 	case "replace_peers":
 		if value != "true" {
-			return ipcErrorf(ipc.IpcErrorInvalid, "failed to set replace_peers, invalid value: %v", value)
+			return ipcErrorf(
+				ipc.IpcErrorInvalid,
+				"failed to set replace_peers, invalid value: %v",
+				value,
+			)
 		}
 		device.log.Verbosef("UAPI: Removing all peers")
 		device.RemoveAllPeers()
 
+	case "jc":
+		jc, err := strconv.ParseUint(value, 10, 32)
+		if err != nil {
+			return ipcErrorf(ipc.IpcErrorInvalid, "failed to parse jc: %w", err)
+		}
+
+		device.log.Verbosef("UAPI: Updating junk count")
+		device.junk.count.Store(uint32(jc))
+
+	case "jmin":
+		jmin, err := strconv.ParseUint(value, 10, 32)
+		if err != nil {
+			return ipcErrorf(ipc.IpcErrorInvalid, "failed to parse jmin: %w", err)
+		}
+
+		device.log.Verbosef("UAPI: Updating junk min")
+		device.junk.min.Store(uint32(jmin))
+
+	case "jmax":
+		jmax, err := strconv.ParseUint(value, 10, 32)
+		if err != nil {
+			return ipcErrorf(ipc.IpcErrorInvalid, "failed to parse jmax: %w", err)
+		}
+
+		device.log.Verbosef("UAPI: Updating junk max")
+		device.junk.max.Store(uint32(jmax))
+
+	case "s1":
+		padding, err := strconv.ParseUint(value, 10, 16)
+		if err != nil {
+			return ipcErrorf(ipc.IpcErrorInvalid, "failed to parse s1: %w", err)
+		}
+		ipcDev.paddings.init = uint32(padding)
+
+	case "s2":
+		padding, err := strconv.ParseUint(value, 10, 16)
+		if err != nil {
+			return ipcErrorf(ipc.IpcErrorInvalid, "failed to parse s2: %w", err)
+		}
+		ipcDev.paddings.response = uint32(padding)
+
+	case "s3":
+		padding, err := strconv.ParseUint(value, 10, 16)
+		if err != nil {
+			return ipcErrorf(ipc.IpcErrorInvalid, "failed to parse s3: %w", err)
+		}
+		ipcDev.paddings.cookie = uint32(padding)
+
+	case "s4":
+		padding, err := strconv.ParseUint(value, 10, 16)
+		if err != nil {
+			return ipcErrorf(ipc.IpcErrorInvalid, "failed to parse s4: %w", err)
+		}
+		ipcDev.paddings.transport = uint32(padding)
+
+	case "h1":
+		var rang UintRange
+		if err := rang.FromString(value); err != nil {
+			return ipcErrorf(ipc.IpcErrorInvalid, "failed to parse H1: %w", err)
+		}
+		ipcDev.headers.init = rang
+
+	case "h2":
+		var rang UintRange
+		if err := rang.FromString(value); err != nil {
+			return ipcErrorf(ipc.IpcErrorInvalid, "failed to parse H2: %w", err)
+		}
+		ipcDev.headers.response = rang
+
+	case "h3":
+		var rang UintRange
+		if err := rang.FromString(value); err != nil {
+			return ipcErrorf(ipc.IpcErrorInvalid, "failed to parse H3: %w", err)
+		}
+		ipcDev.headers.cookie = rang
+
+	case "h4":
+		var rang UintRange
+		if err := rang.FromString(value); err != nil {
+			return ipcErrorf(ipc.IpcErrorInvalid, "failed to parse H4: %w", err)
+		}
+		ipcDev.headers.transport = rang
+
+	case "i1":
+		chain, err := newObfChain(value)
+		if err != nil {
+			return ipcErrorf(ipc.IpcErrorInvalid, "failed to parse I1: %w", err)
+		}
+		device.ipackets[0] = chain
+
+	case "i2":
+		chain, err := newObfChain(value)
+		if err != nil {
+			return ipcErrorf(ipc.IpcErrorInvalid, "failed to parse I2: %w", err)
+		}
+		device.ipackets[1] = chain
+
+	case "i3":
+		chain, err := newObfChain(value)
+		if err != nil {
+			return ipcErrorf(ipc.IpcErrorInvalid, "failed to parse I3: %w", err)
+		}
+		device.ipackets[2] = chain
+
+	case "i4":
+		chain, err := newObfChain(value)
+		if err != nil {
+			return ipcErrorf(ipc.IpcErrorInvalid, "failed to parse I4: %w", err)
+		}
+		device.ipackets[3] = chain
+
+	case "i5":
+		chain, err := newObfChain(value)
+		if err != nil {
+			return ipcErrorf(ipc.IpcErrorInvalid, "failed to parse I5: %w", err)
+		}
+		device.ipackets[4] = chain
+
+	case "header_protection_key":
+		var key HeaderCipherKey
+		err := key.FromHex(value)
+		if err != nil {
+			return ipcErrorf(ipc.IpcErrorInvalid, "failed to set header_protection_key: %w", err)
+		}
+		ipcDev.headerProtectionKey = key
+
+	case "content_padding_addition":
+		var rang UintRange
+		if err := rang.FromString(value); err != nil {
+			return ipcErrorf(ipc.IpcErrorInvalid, "failed to parse content_padding_addition: %w", err)
+		}
+
+		device.log.Verbosef("UAPI: Updating content padding addition")
+		device.contentPaddingAddition.Store(rang)
+
+	case "rekey_after_time":
+		var rang UintRange
+		if err := rang.FromString(value); err != nil {
+			return ipcErrorf(ipc.IpcErrorInvalid, "failed to parse rekey after time: %w", err)
+		}
+		device.log.Verbosef("UAPI: Updating rekey after time")
+		device.timings.rekeyAfterTimeSec.Store(rang)
+
+	case "rekey_timeout":
+		var rang UintRange
+		if err := rang.FromString(value); err != nil {
+			return ipcErrorf(ipc.IpcErrorInvalid, "failed to parse rekey timeout: %w", err)
+		}
+		device.log.Verbosef("UAPI: Updating rekey timeout")
+		device.timings.rekeyTimeoutSec.Store(rang)
+
+	case "reject_after_time":
+		var rang UintRange
+		if err := rang.FromString(value); err != nil {
+			return ipcErrorf(ipc.IpcErrorInvalid, "failed to parse reject after time: %w", err)
+		}
+		device.log.Verbosef("UAPI: Updating reject after time")
+		device.timings.rejectAfterTimeSec.Store(rang)
+
+	case "keepalive_timeout":
+		var rang UintRange
+		if err := rang.FromString(value); err != nil {
+			return ipcErrorf(ipc.IpcErrorInvalid, "failed to parse keepalive timeout: %w", err)
+		}
+		device.log.Verbosef("UAPI: Updating keepalive timeout")
+		device.timings.keepaliveTimeoutSec.Store(rang)
+
+	case "max_handshake_attempts":
+		var rang UintRange
+		if err := rang.FromString(value); err != nil {
+			return ipcErrorf(ipc.IpcErrorInvalid, "failed to parse max handshake attempts: %w", err)
+		}
+		device.log.Verbosef("UAPI: Updating max handshake attempts")
+		device.timings.maxHandshakeAttemps.Store(rang)
+
+	case "random_trailers":
+		val, err := strconv.ParseBool(value)
+		if err != nil {
+			return ipcErrorf(ipc.IpcErrorInvalid, "failed to parse random trailers: %w", err)
+		}
+		device.log.Verbosef("UAPI: Updating random trailers")
+		device.randomTrailers.Store(val)
+
+	case "disable_cookies":
+		val, err := strconv.ParseBool(value)
+		if err != nil {
+			return ipcErrorf(ipc.IpcErrorInvalid, "failed to parse disable cookies: %w", err)
+		}
+		device.log.Verbosef("UAPI: Updating disable cookies")
+		device.disableCookies.Store(val)
+
 	default:
 		return ipcErrorf(ipc.IpcErrorInvalid, "invalid UAPI device key: %v", key)
 	}
@@ -262,7 +563,7 @@ func (peer *ipcSetPeer) handlePostConfig() {
 		return
 	}
 	if peer.created {
-		peer.disableRoaming = peer.device.net.brokenRoaming && peer.endpoint != nil
+		peer.endpoint.disableRoaming = peer.device.net.brokenRoaming && peer.endpoint.val != nil
 	}
 	if peer.device.isUp() {
 		peer.Start()
@@ -273,7 +574,10 @@ func (peer *ipcSetPeer) handlePostConfig() {
 	}
 }
 
-func (device *Device) handlePublicKeyLine(peer *ipcSetPeer, value string) error {
+func (device *Device) handlePublicKeyLine(
+	peer *ipcSetPeer,
+	value string,
+) error {
 	// Load/create the peer we are configuring.
 	var publicKey NoisePublicKey
 	err := publicKey.FromHex(value)
@@ -303,12 +607,19 @@ func (device *Device) handlePublicKeyLine(peer *ipcSetPeer, value string) error
 	return nil
 }
 
-func (device *Device) handlePeerLine(peer *ipcSetPeer, key, value string) error {
+func (device *Device) handlePeerLine(
+	peer *ipcSetPeer,
+	key, value string,
+) error {
 	switch key {
 	case "update_only":
 		// allow disabling of creation
 		if value != "true" {
-			return ipcErrorf(ipc.IpcErrorInvalid, "failed to set update only, invalid value: %v", value)
+			return ipcErrorf(
+				ipc.IpcErrorInvalid,
+				"failed to set update only, invalid value: %v",
+				value,
+			)
 		}
 		if peer.created && !peer.dummy {
 			device.RemovePeer(peer.handshake.remoteStatic)
@@ -345,27 +656,31 @@ func (device *Device) handlePeerLine(peer *ipcSetPeer, key, value string) error
 		if err != nil {
 			return ipcErrorf(ipc.IpcErrorInvalid, "failed to set endpoint %v: %w", value, err)
 		}
-		peer.Lock()
-		defer peer.Unlock()
-		peer.endpoint = endpoint
+		peer.endpoint.Lock()
+		defer peer.endpoint.Unlock()
+		peer.endpoint.val = endpoint
 
 	case "persistent_keepalive_interval":
 		device.log.Verbosef("%v - UAPI: Updating persistent keepalive interval", peer.Peer)
 
-		secs, err := strconv.ParseUint(value, 10, 16)
-		if err != nil {
+		var rang UintRange
+		if err := rang.FromString(value); err != nil {
 			return ipcErrorf(ipc.IpcErrorInvalid, "failed to set persistent keepalive interval: %w", err)
 		}
 
-		old := peer.persistentKeepaliveInterval.Swap(uint32(secs))
+		old := peer.persistentKeepaliveInterval.Swap(rang)
 
 		// Send immediate keepalive if we're turning it on and before it wasn't on.
-		peer.pkaOn = old == 0 && secs != 0
+		peer.pkaOn = old.IsZero() && !rang.IsZero()
 
 	case "replace_allowed_ips":
 		device.log.Verbosef("%v - UAPI: Removing all allowedips", peer.Peer)
 		if value != "true" {
-			return ipcErrorf(ipc.IpcErrorInvalid, "failed to replace allowedips, invalid value: %v", value)
+			return ipcErrorf(
+				ipc.IpcErrorInvalid,
+				"failed to replace allowedips, invalid value: %v",
+				value,
+			)
 		}
 		if peer.dummy {
 			return nil
@@ -373,7 +688,14 @@ func (device *Device) handlePeerLine(peer *ipcSetPeer, key, value string) error
 		device.allowedips.RemoveByPeer(peer.Peer)
 
 	case "allowed_ip":
-		device.log.Verbosef("%v - UAPI: Adding allowedip", peer.Peer)
+		add := true
+		verb := "Adding"
+		if len(value) > 0 && value[0] == '-' {
+			add = false
+			verb = "Removing"
+			value = value[1:]
+		}
+		device.log.Verbosef("%v - UAPI: %s allowedip", peer.Peer, verb)
 		prefix, err := netip.ParsePrefix(value)
 		if err != nil {
 			return ipcErrorf(ipc.IpcErrorInvalid, "failed to set allowed ip: %w", err)
@@ -381,7 +703,11 @@ func (device *Device) handlePeerLine(peer *ipcSetPeer, key, value string) error
 		if peer.dummy {
 			return nil
 		}
-		device.allowedips.Insert(prefix, peer.Peer)
+		if add {
+			device.allowedips.Insert(prefix, peer.Peer)
+		} else {
+			device.allowedips.Remove(prefix, peer.Peer)
+		}
 
 	case "protocol_version":
 		if value != "1" {
@@ -433,7 +759,11 @@ func (device *Device) IpcHandle(socket net.Conn) {
 				return
 			}
 			if nextByte != '\n' {
-				err = ipcErrorf(ipc.IpcErrorInvalid, "trailing character in UAPI get: %q", nextByte)
+				err = ipcErrorf(
+					ipc.IpcErrorInvalid,
+					"trailing character in UAPI get: %q",
+					nextByte,
+				)
 				break
 			}
 			err = device.IpcGetOperation(buffered.Writer)
@@ -457,3 +787,91 @@ func (device *Device) IpcHandle(socket net.Conn) {
 		buffered.Flush()
 	}
 }
+
+type ipcSetDevice struct {
+	headers struct {
+		init      UintRange
+		response  UintRange
+		cookie    UintRange
+		transport UintRange
+	}
+	paddings struct {
+		init      uint32
+		response  uint32
+		cookie    uint32
+		transport uint32
+	}
+	headerProtectionKey HeaderCipherKey
+}
+
+func (d *ipcSetDevice) fromDevice(device *Device) {
+	device.headerProtection.RLock()
+	defer device.headerProtection.RUnlock()
+
+	d.headers.init = device.headers.init.Load()
+	d.headers.response = device.headers.response.Load()
+	d.headers.cookie = device.headers.cookie.Load()
+	d.headers.transport = device.headers.transport.Load()
+
+	d.paddings.init = device.paddings.init.Load()
+	d.paddings.response = device.paddings.response.Load()
+	d.paddings.cookie = device.paddings.cookie.Load()
+	d.paddings.transport = device.paddings.transport.Load()
+
+	d.headerProtectionKey = device.headerProtection.key
+}
+
+func (d *ipcSetDevice) mergeWithDevice(device *Device) error {
+	device.headerProtection.Lock()
+	defer device.headerProtection.Unlock()
+
+	headers := []UintRange{d.headers.init, d.headers.response, d.headers.cookie, d.headers.transport}
+	for i := 0; i < len(headers); i++ {
+		for j := i + 1; j < len(headers); j++ {
+			left := headers[i]
+			right := headers[j]
+
+			if left.Overlap(right) {
+				return errors.New("headers must not overlap")
+			}
+		}
+	}
+
+	device.log.Verbosef("UAPI: Updating h1 padding")
+	device.headers.init.Store(d.headers.init)
+
+	device.log.Verbosef("UAPI: Updating h2 padding")
+	device.headers.response.Store(d.headers.response)
+
+	device.log.Verbosef("UAPI: Updating h3 padding")
+	device.headers.cookie.Store(d.headers.cookie)
+
+	device.log.Verbosef("UAPI: Updating h4 padding")
+	device.headers.transport.Store(d.headers.transport)
+
+	if !d.headerProtectionKey.IsZero() {
+		paddings := []uint32{d.paddings.init, d.paddings.response, d.paddings.cookie, d.paddings.transport}
+		for i, padding := range paddings {
+			if padding < HeaderCipherNonceSize {
+				return fmt.Errorf("S%d must be more then %d to use headerProtection", i, HeaderCipherNonceSize)
+			}
+		}
+	}
+
+	device.log.Verbosef("UAPI: Updating s1 padding")
+	device.paddings.init.Store(d.paddings.init)
+
+	device.log.Verbosef("UAPI: Updating s2 padding")
+	device.paddings.response.Store(d.paddings.response)
+
+	device.log.Verbosef("UAPI: Updating s3 padding")
+	device.paddings.cookie.Store(d.paddings.cookie)
+
+	device.log.Verbosef("UAPI: Updating s4 padding")
+	device.paddings.transport.Store(d.paddings.transport)
+
+	device.log.Verbosef("UAPI: Updating header protection key")
+	device.headerProtection.key = d.headerProtectionKey
+
+	return nil
+}

format_test.go

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 package main
 

go.mod

@@ -1,16 +1,35 @@
-module golang.zx2c4.com/wireguard
+module github.com/amnezia-vpn/amneziawg-go/v3
 
-go 1.20
+go 1.25.0
 
 require (
-	golang.org/x/crypto v0.6.0
-	golang.org/x/net v0.7.0
-	golang.org/x/sys v0.5.1-0.20230222185716-a3b23cc77e89
+	github.com/goccy/go-yaml v1.17.1
+	go.uber.org/atomic v1.11.0
+	golang.getoutline.org/sdk v0.0.23
+	golang.getoutline.org/sdk/x v0.2.0
+	golang.org/x/crypto v0.42.0
+	golang.org/x/net v0.44.0
+	golang.org/x/sys v0.36.0
 	golang.zx2c4.com/wintun v0.0.0-20230126152724-0fa3db229ce2
-	gvisor.dev/gvisor v0.0.0-20221203005347-703fd9b7fbc0
+	gvisor.dev/gvisor v0.0.0-20231202080848-1f7806d17489
 )
 
 require (
-	github.com/google/btree v1.0.1 // indirect
-	golang.org/x/time v0.0.0-20191024005414-555d28b269f0 // indirect
+	github.com/go-task/slim-sprig v0.0.0-20230315185526-52ccab3ef572 // indirect
+	github.com/google/btree v1.1.3 // indirect
+	github.com/google/pprof v0.0.0-20211214055906-6f57359322fd // indirect
+	github.com/gorilla/websocket v1.5.3 // indirect
+	github.com/onsi/ginkgo/v2 v2.12.0 // indirect
+	github.com/quic-go/qpack v0.5.1 // indirect
+	github.com/quic-go/quic-go v0.48.1 // indirect
+	github.com/shadowsocks/go-shadowsocks2 v0.1.5 // indirect
+	github.com/stretchr/testify v1.10.0 // indirect
+	go.uber.org/mock v0.4.0 // indirect
+	golang.org/x/exp v0.0.0-20240506185415-9bf2ced13842 // indirect
+	golang.org/x/mobile v0.0.0-20240520174638-fa72addaaa1b // indirect
+	golang.org/x/mod v0.28.0 // indirect
+	golang.org/x/sync v0.17.0 // indirect
+	golang.org/x/text v0.29.0 // indirect
+	golang.org/x/time v0.9.0 // indirect
+	golang.org/x/tools v0.37.0 // indirect
 )

go.sum

@@ -1,14 +1,95 @@
-github.com/google/btree v1.0.1 h1:gK4Kx5IaGY9CD5sPJ36FHiBJ6ZXl0kilRiiCj+jdYp4=
-github.com/google/btree v1.0.1/go.mod h1:xXMiIv4Fb/0kKde4SpL7qlzvu5cMJDRkFDxJfI9uaxA=
-golang.org/x/crypto v0.6.0 h1:qfktjS5LUO+fFKeJXZ+ikTRijMmljikvG68fpMMruSc=
-golang.org/x/crypto v0.6.0/go.mod h1:OFC/31mSvZgRz0V1QTNCzfAI1aIRzbiufJtkMIlEp58=
-golang.org/x/net v0.7.0 h1:rJrUqqhjsgNp7KqAIc25s9pZnjU7TUcSY7HcVZjdn1g=
-golang.org/x/net v0.7.0/go.mod h1:2Tu9+aMcznHK/AK1HMvgo6xiTLG5rD5rZLDS+rp2Bjs=
-golang.org/x/sys v0.5.1-0.20230222185716-a3b23cc77e89 h1:260HNjMTPDya+jq5AM1zZLgG9pv9GASPAGiEEJUbRg4=
-golang.org/x/sys v0.5.1-0.20230222185716-a3b23cc77e89/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/time v0.0.0-20191024005414-555d28b269f0 h1:/5xXl8Y5W96D+TtHSlonuFqGHIWVuyCkGJLwGh9JJFs=
-golang.org/x/time v0.0.0-20191024005414-555d28b269f0/go.mod h1:tRJNPiyCQ0inRvYxbN9jk5I+vvW/OXSQhTDSoE431IQ=
+github.com/chzyer/logex v1.1.10/go.mod h1:+Ywpsq7O8HXn0nuIou7OrIPyXbp3wmkHB+jjWRnGsAI=
+github.com/chzyer/readline v0.0.0-20180603132655-2972be24d48e/go.mod h1:nSuG5e5PlCu98SY8svDHJxuZscDgtXS6KTTbou5AhLI=
+github.com/chzyer/test v0.0.0-20180213035817-a1ea475d72b1/go.mod h1:Q3SI9o4m/ZMnBNeIyt5eFwwo7qiLfzFZmjNmxjkiQlU=
+github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/go-logr/logr v1.2.4 h1:g01GSCwiDw2xSZfjJ2/T9M+S6pFdcNtFYsp+Y43HYDQ=
+github.com/go-logr/logr v1.2.4/go.mod h1:jdQByPbusPIv2/zmleS9BjJVeZ6kBagPoEUsqbVz/1A=
+github.com/go-task/slim-sprig v0.0.0-20230315185526-52ccab3ef572 h1:tfuBGBXKqDEevZMzYi5KSi8KkcZtzBcTgAUUtapy0OI=
+github.com/go-task/slim-sprig v0.0.0-20230315185526-52ccab3ef572/go.mod h1:9Pwr4B2jHnOSGXyyzV8ROjYa2ojvAY6HCGYYfMoC3Ls=
+github.com/goccy/go-yaml v1.17.1 h1:LI34wktB2xEE3ONG/2Ar54+/HJVBriAGJ55PHls4YuY=
+github.com/goccy/go-yaml v1.17.1/go.mod h1:XBurs7gK8ATbW4ZPGKgcbrY1Br56PdM69F7LkFRi1kA=
+github.com/golang/protobuf v1.5.3 h1:KhyjKVUg7Usr/dYsdSqoFveMYd5ko72D+zANwlG1mmg=
+github.com/golang/protobuf v1.5.3/go.mod h1:XVQd3VNwM+JqD3oG2Ue2ip4fOMUkwXdXDdiuN0vRsmY=
+github.com/google/btree v1.1.3 h1:CVpQJjYgC4VbzxeGVHfvZrv1ctoYCAI8vbl07Fcxlyg=
+github.com/google/btree v1.1.3/go.mod h1:qOPhT0dTNdNzV6Z/lhRX0YXUafgPLFUh+gZMl761Gm4=
+github.com/google/go-cmp v0.6.0 h1:ofyhxvXcZhMsU5ulbFiLKl/XBFqE1GSq7atu8tAmTRI=
+github.com/google/go-cmp v0.6.0/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeNGIjoY=
+github.com/google/gopacket v1.1.19 h1:ves8RnFZPGiFnTS0uPQStjwru6uO6h+nlr9j6fL7kF8=
+github.com/google/gopacket v1.1.19/go.mod h1:iJ8V8n6KS+z2U1A8pUwu8bW5SyEMkXJB8Yo/Vo+TKTo=
+github.com/google/pprof v0.0.0-20211214055906-6f57359322fd h1:1FjCyPC+syAzJ5/2S8fqdZK1R22vvA0J7JZKcuOIQ7Y=
+github.com/google/pprof v0.0.0-20211214055906-6f57359322fd/go.mod h1:KgnwoLYCZ8IQu3XUZ8Nc/bM9CCZFOyjUNOSygVozoDg=
+github.com/gorilla/websocket v1.5.3 h1:saDtZ6Pbx/0u+bgYQ3q96pZgCzfhKXGPqt7kZ72aNNg=
+github.com/gorilla/websocket v1.5.3/go.mod h1:YR8l580nyteQvAITg2hZ9XVh4b55+EU/adAjf1fMHhE=
+github.com/ianlancetaylor/demangle v0.0.0-20210905161508-09a460cdf81d/go.mod h1:aYm2/VgdVmcIU8iMfdMvDMsRAQjcfZSKFby6HOFvi/w=
+github.com/onsi/ginkgo/v2 v2.12.0 h1:UIVDowFPwpg6yMUpPjGkYvf06K3RAiJXUhCxEwQVHRI=
+github.com/onsi/ginkgo/v2 v2.12.0/go.mod h1:ZNEzXISYlqpb8S36iN71ifqLi3vVD1rVJGvWRCJOUpQ=
+github.com/onsi/gomega v1.27.10 h1:naR28SdDFlqrG6kScpT8VWpu1xWY5nJRCF3XaYyBjhI=
+github.com/onsi/gomega v1.27.10/go.mod h1:RsS8tutOdbdgzbPtzzATp12yT7kM5I5aElG3evPbQ0M=
+github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
+github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/quic-go/qpack v0.5.1 h1:giqksBPnT/HDtZ6VhtFKgoLOWmlyo9Ei6u9PqzIMbhI=
+github.com/quic-go/qpack v0.5.1/go.mod h1:+PC4XFrEskIVkcLzpEkbLqq1uCoxPhQuvK5rH1ZgaEg=
+github.com/quic-go/quic-go v0.48.1 h1:y/8xmfWI9qmGTc+lBr4jKRUWLGSlSigv847ULJ4hYXA=
+github.com/quic-go/quic-go v0.48.1/go.mod h1:yBgs3rWBOADpga7F+jJsb6Ybg1LSYiQvwWlLX+/6HMs=
+github.com/riobard/go-bloom v0.0.0-20200614022211-cdc8013cb5b3 h1:f/FNXud6gA3MNr8meMVVGxhp+QBTqY91tM8HjEuMjGg=
+github.com/riobard/go-bloom v0.0.0-20200614022211-cdc8013cb5b3/go.mod h1:HgjTstvQsPGkxUsCd2KWxErBblirPizecHcpD3ffK+s=
+github.com/shadowsocks/go-shadowsocks2 v0.1.5 h1:PDSQv9y2S85Fl7VBeOMF9StzeXZyK1HakRm86CUbr28=
+github.com/shadowsocks/go-shadowsocks2 v0.1.5/go.mod h1:AGGpIoek4HRno4xzyFiAtLHkOpcoznZEkAccaI/rplM=
+github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
+github.com/stretchr/testify v1.6.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
+github.com/stretchr/testify v1.10.0 h1:Xv5erBjTwe/5IxqUQTdXv5kgmIvbHo3QQyRwhJsOfJA=
+github.com/stretchr/testify v1.10.0/go.mod h1:r2ic/lqez/lEtzL7wO/rwa5dbSLXVDPFyf8C91i36aY=
+github.com/things-go/go-socks5 v0.0.5 h1:qvKaGcBkfDrUL33SchHN93srAmYGzb4CxSM2DPYufe8=
+github.com/things-go/go-socks5 v0.0.5/go.mod h1:mtzInf8v5xmsBpHZVbIw2YQYhc4K0jRwzfsH64Uh0IQ=
+go.uber.org/atomic v1.11.0 h1:ZvwS0R+56ePWxUNi+Atn9dWONBPp/AUETXlHW0DxSjE=
+go.uber.org/atomic v1.11.0/go.mod h1:LUxbIzbOniOlMKjJjyPfpl4v+PKK2cNJn91OQbhoJI0=
+go.uber.org/mock v0.4.0 h1:VcM4ZOtdbR4f6VXfiOpwpVJDL6lCReaZ6mw31wqh7KU=
+go.uber.org/mock v0.4.0/go.mod h1:a6FSlNadKUHUa9IP5Vyt1zh4fC7uAwxMutEAscFbkZc=
+golang.getoutline.org/sdk v0.0.23 h1:UKoKCrRH3Ed6Jpg8ODYwOo6O1B1lvfIHPreMrTkSTcc=
+golang.getoutline.org/sdk v0.0.23/go.mod h1:nKZlO//e/sRFk+rp8gm8EJ5RasDSyY+fGDNSd3I2iaA=
+golang.getoutline.org/sdk/x v0.2.0 h1:4kuT2SgkPXktwPwT6CXuF+Jwe+COAGqiBDZbgJkS5fM=
+golang.getoutline.org/sdk/x v0.2.0/go.mod h1:vyWoHW0PUsnRHdLXiDGv1Z8X48Asp2ALgwIQfJfAaNs=
+golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
+golang.org/x/crypto v0.0.0-20210220033148-5ea612d1eb83/go.mod h1:jdWPYTVW3xRLrWPugEBEK3UY2ZEsg3UU495nc5E+M+I=
+golang.org/x/crypto v0.42.0 h1:chiH31gIWm57EkTXpwnqf8qeuMUi0yekh6mT2AvFlqI=
+golang.org/x/crypto v0.42.0/go.mod h1:4+rDnOTJhQCx2q7/j6rAN5XDw8kPjeaXEUR2eL94ix8=
+golang.org/x/exp v0.0.0-20240506185415-9bf2ced13842 h1:vr/HnozRka3pE4EsMEg1lgkXJkTFJCVUX+S/ZT6wYzM=
+golang.org/x/exp v0.0.0-20240506185415-9bf2ced13842/go.mod h1:XtvwrStGgqGPLc4cjQfWqZHG1YFdYs6swckp8vpsjnc=
+golang.org/x/mobile v0.0.0-20240520174638-fa72addaaa1b h1:WX7nnnLfCEXg+FmdYZPai2XuP3VqCP1HZVMST0n9DF0=
+golang.org/x/mobile v0.0.0-20240520174638-fa72addaaa1b/go.mod h1:EiXZlVfUTaAyySFVJb9rsODuiO+WXu8HrUuySb7nYFw=
+golang.org/x/mod v0.28.0 h1:gQBtGhjxykdjY9YhZpSlZIsbnaE2+PgjfLWUQTnoZ1U=
+golang.org/x/mod v0.28.0/go.mod h1:yfB/L0NOf/kmEbXjzCPOx1iK1fRutOydrCMsqRhEBxI=
+golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
+golang.org/x/net v0.44.0 h1:evd8IRDyfNBMBTTY5XRF1vaZlD+EmWx6x8PkhR04H/I=
+golang.org/x/net v0.44.0/go.mod h1:ECOoLqd5U3Lhyeyo/QDCEVQ4sNgYsqvCZ722XogGieY=
+golang.org/x/sync v0.17.0 h1:l60nONMj9l5drqw6jlhIELNv9I0A4OFgRsG9k2oT9Ug=
+golang.org/x/sync v0.17.0/go.mod h1:9KTHXmSnoGruLpwFjVSX0lNNA75CykiMECbovNTZqGI=
+golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
+golang.org/x/sys v0.0.0-20191026070338-33540a1f6037/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20211007075335-d3039528d8ac/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.36.0 h1:KVRy2GtZBrk1cBYA7MKu5bEZFxQk4NIDV6RLVcC8o0k=
+golang.org/x/sys v0.36.0/go.mod h1:OgkHotnGiDImocRcuBABYBEXf8A9a87e/uXjp9XT3ks=
+golang.org/x/term v0.0.0-20201117132131-f5c789dd3221/go.mod h1:Nr5EML6q2oocZ2LXRh80K7BxOlk5/8JxuGnuhpl+muw=
+golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
+golang.org/x/text v0.29.0 h1:1neNs90w9YzJ9BocxfsQNHKuAT4pkghyXc4nhZ6sJvk=
+golang.org/x/text v0.29.0/go.mod h1:7MhJOA9CD2qZyOKYazxdYMF85OwPdEr9jTtBpO7ydH4=
+golang.org/x/time v0.9.0 h1:EsRrnYcQiGH+5FfbgvV4AP7qEZstoyrHB0DzarOQ4ZY=
+golang.org/x/time v0.9.0/go.mod h1:3BpzKBy/shNhVucY/MWOyx10tF3SFh9QdLuxbVysPQM=
+golang.org/x/tools v0.37.0 h1:DVSRzp7FwePZW356yEAChSdNcQo6Nsp+fex1SUW09lE=
+golang.org/x/tools v0.37.0/go.mod h1:MBN5QPQtLMHVdvsbtarmTNukZDdgwdwlO5qGacAzF0w=
+golang.org/x/tools/go/expect v0.1.1-deprecated h1:jpBZDwmgPhXsKZC6WhL20P4b/wmnpsEAGHaNy0n/rJM=
+golang.org/x/tools/go/expect v0.1.1-deprecated/go.mod h1:eihoPOH+FgIqa3FpoTwguz/bVUSGBlGQU67vpBeOrBY=
+golang.org/x/tools/go/packages/packagestest v0.1.1-deprecated h1:1h2MnaIAIXISqTFKdENegdpAgUXz6NrPEsbIeWaBRvM=
+golang.org/x/tools/go/packages/packagestest v0.1.1-deprecated/go.mod h1:RVAQXBGNv1ib0J382/DPCRS/BPnsGebyM1Gj5VSDpG8=
 golang.zx2c4.com/wintun v0.0.0-20230126152724-0fa3db229ce2 h1:B82qJJgjvYKsXS9jeunTOisW56dUokqW/FOteYJJ/yg=
 golang.zx2c4.com/wintun v0.0.0-20230126152724-0fa3db229ce2/go.mod h1:deeaetjYA+DHMHg+sMSMI58GrEteJUUzzw7en6TJQcI=
-gvisor.dev/gvisor v0.0.0-20221203005347-703fd9b7fbc0 h1:Wobr37noukisGxpKo5jAsLREcpj61RxrWYzD8uwveOY=
-gvisor.dev/gvisor v0.0.0-20221203005347-703fd9b7fbc0/go.mod h1:Dn5idtptoW1dIos9U6A2rpebLs/MtTwFacjKb8jLdQA=
+google.golang.org/protobuf v1.33.0 h1:uNO2rsAINq/JlFpSdYEKIZ0uKD/R9cpdv0T+yoGwGmI=
+google.golang.org/protobuf v1.33.0/go.mod h1:c6P6GXX6sHbq/GpV6MGZEdwhWPcYBgnhAHhKbcUYpos=
+gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/yaml.v3 v3.0.0-20200313102051-9f266ea9e77c/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
+gopkg.in/yaml.v3 v3.0.1 h1:fxVm/GzAzEWqLHuvctI91KS9hhNmmWOoWu0XTYJS7CA=
+gopkg.in/yaml.v3 v3.0.1/go.mod h1:K4uyk7z7BCEPqu6E+C64Yfv1cQ7kz7rIZviUmN+EgEM=
+gvisor.dev/gvisor v0.0.0-20231202080848-1f7806d17489 h1:ze1vwAdliUAr68RQ5NtufWaXaOg8WUO2OACzEV+TNdE=
+gvisor.dev/gvisor v0.0.0-20231202080848-1f7806d17489/go.mod h1:10sU+Uh5KKNv1+2x2A0Gvzt8FjD3ASIhorV3YsauXhk=

ipc/namedpipe/namedpipe_test.go

@@ -20,8 +20,8 @@ import (
 	"testing"
 	"time"
 
+	"github.com/amnezia-vpn/amneziawg-go/v3/ipc/namedpipe"
 	"golang.org/x/sys/windows"
-	"golang.zx2c4.com/wireguard/ipc/namedpipe"
 )
 
 func randomPipePath() string {

ipc/uapi_bsd.go

@@ -2,7 +2,7 @@
 
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package ipc

ipc/uapi_linux.go

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package ipc
@@ -9,8 +9,8 @@ import (
 	"net"
 	"os"
 
+	"github.com/amnezia-vpn/amneziawg-go/v3/rwcancel"
 	"golang.org/x/sys/unix"
-	"golang.zx2c4.com/wireguard/rwcancel"
 )
 
 type UAPIListener struct {

ipc/uapi_unix.go

@@ -2,7 +2,7 @@
 
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package ipc
@@ -26,7 +26,7 @@ const (
 
 // socketDirectory is variable because it is modified by a linker
 // flag in wireguard-android.
-var socketDirectory = "/var/run/wireguard"
+var socketDirectory = "/var/run/amneziawg"
 
 func sockPath(iface string) string {
 	return fmt.Sprintf("%s/%s.sock", socketDirectory, iface)

ipc/uapi_wasm.go

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package ipc

ipc/uapi_windows.go

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package ipc
@@ -8,8 +8,8 @@ package ipc
 import (
 	"net"
 
+	"github.com/amnezia-vpn/amneziawg-go/v3/ipc/namedpipe"
 	"golang.org/x/sys/windows"
-	"golang.zx2c4.com/wireguard/ipc/namedpipe"
 )
 
 // TODO: replace these with actual standard windows error numbers from the win package
@@ -62,7 +62,7 @@ func init() {
 func UAPIListen(name string) (net.Listener, error) {
 	listener, err := (&namedpipe.ListenConfig{
 		SecurityDescriptor: UAPISecurityDescriptor,
-	}).Listen(`\\.\pipe\ProtectedPrefix\Administrators\WireGuard\` + name)
+	}).Listen(`\\.\pipe\ProtectedPrefix\Administrators\AmneziaWG\` + name)
 	if err != nil {
 		return nil, err
 	}

main.go

@@ -2,7 +2,7 @@
 
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package main
@@ -14,11 +14,11 @@ import (
 	"runtime"
 	"strconv"
 
+	"github.com/amnezia-vpn/amneziawg-go/v3/conn"
+	"github.com/amnezia-vpn/amneziawg-go/v3/device"
+	"github.com/amnezia-vpn/amneziawg-go/v3/ipc"
+	"github.com/amnezia-vpn/amneziawg-go/v3/tun"
 	"golang.org/x/sys/unix"
-	"golang.zx2c4.com/wireguard/conn"
-	"golang.zx2c4.com/wireguard/device"
-	"golang.zx2c4.com/wireguard/ipc"
-	"golang.zx2c4.com/wireguard/tun"
 )
 
 const (
@@ -46,20 +46,20 @@ func warning() {
 		return
 	}
 
-	fmt.Fprintln(os.Stderr, "┌──────────────────────────────────────────────────────┐")
-	fmt.Fprintln(os.Stderr, "│                                                      │")
-	fmt.Fprintln(os.Stderr, "│   Running wireguard-go is not required because this  │")
-	fmt.Fprintln(os.Stderr, "│   kernel has first class support for WireGuard. For  │")
-	fmt.Fprintln(os.Stderr, "│   information on installing the kernel module,       │")
-	fmt.Fprintln(os.Stderr, "│   please visit:                                      │")
-	fmt.Fprintln(os.Stderr, "│         https://www.wireguard.com/install/           │")
-	fmt.Fprintln(os.Stderr, "│                                                      │")
-	fmt.Fprintln(os.Stderr, "└──────────────────────────────────────────────────────┘")
+	fmt.Fprintln(os.Stderr, "┌──────────────────────────────────────────────────────────────┐")
+	fmt.Fprintln(os.Stderr, "│                                                              │")
+	fmt.Fprintln(os.Stderr, "│       Running amneziawg-go is not required because this      │")
+	fmt.Fprintln(os.Stderr, "│       kernel has first class support for AmneziaWG. For      │")
+	fmt.Fprintln(os.Stderr, "│       information on installing the kernel module,           │")
+	fmt.Fprintln(os.Stderr, "│       please visit:                                          │")
+	fmt.Fprintln(os.Stderr, "| https://github.com/amnezia-vpn/amneziawg-linux-kernel-module │")
+	fmt.Fprintln(os.Stderr, "│                                                              │")
+	fmt.Fprintln(os.Stderr, "└──────────────────────────────────────────────────────────────┘")
 }
 
 func main() {
 	if len(os.Args) == 2 && os.Args[1] == "--version" {
-		fmt.Printf("wireguard-go v%s\n\nUserspace WireGuard daemon for %s-%s.\nInformation available at https://www.wireguard.com.\nCopyright (C) Jason A. Donenfeld <Jason@zx2c4.com>.\n", Version, runtime.GOOS, runtime.GOARCH)
+		fmt.Printf("amneziawg-go %s\n\nUserspace AmneziaWG daemon for %s-%s.\nInformation available at https://amnezia.org\n", Version, runtime.GOOS, runtime.GOARCH)
 		return
 	}
 
@@ -145,7 +145,7 @@ func main() {
 		fmt.Sprintf("(%s) ", interfaceName),
 	)
 
-	logger.Verbosef("Starting wireguard-go version %s", Version)
+	logger.Verbosef("Starting amneziawg-go version %s", Version)
 
 	if err != nil {
 		logger.Errorf("Failed to create TUN device: %v", err)

main_windows.go

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package main
@@ -12,11 +12,11 @@ import (
 
 	"golang.org/x/sys/windows"
 
-	"golang.zx2c4.com/wireguard/conn"
-	"golang.zx2c4.com/wireguard/device"
-	"golang.zx2c4.com/wireguard/ipc"
+	"github.com/amnezia-vpn/amneziawg-go/v3/conn"
+	"github.com/amnezia-vpn/amneziawg-go/v3/device"
+	"github.com/amnezia-vpn/amneziawg-go/v3/ipc"
 
-	"golang.zx2c4.com/wireguard/tun"
+	"github.com/amnezia-vpn/amneziawg-go/v3/tun"
 )
 
 const (
@@ -30,13 +30,13 @@ func main() {
 	}
 	interfaceName := os.Args[1]
 
-	fmt.Fprintln(os.Stderr, "Warning: this is a test program for Windows, mainly used for debugging this Go package. For a real WireGuard for Windows client, the repo you want is <https://git.zx2c4.com/wireguard-windows/>, which includes this code as a module.")
+	fmt.Fprintln(os.Stderr, "Warning: this is a test program for Windows, mainly used for debugging this Go package. For a real AmneziaWG for Windows client, please visit: https://amnezia.org")
 
 	logger := device.NewLogger(
 		device.LogLevelVerbose,
 		fmt.Sprintf("(%s) ", interfaceName),
 	)
-	logger.Verbosef("Starting wireguard-go version %s", Version)
+	logger.Verbosef("Starting amneziawg-go version %s", Version)
 
 	tun, err := tun.CreateTUN(interfaceName, 0)
 	if err == nil {

outline/dialer.go

@@ -0,0 +1,77 @@
+package outline
+
+import (
+	"context"
+	"fmt"
+	"net"
+	"net/netip"
+
+	"github.com/amnezia-vpn/amneziawg-go/v3/conn"
+	"github.com/amnezia-vpn/amneziawg-go/v3/device"
+	"github.com/amnezia-vpn/amneziawg-go/v3/tun/netstack"
+	"golang.getoutline.org/sdk/transport"
+	"gvisor.dev/gvisor/pkg/tcpip/adapters/gonet"
+)
+
+type DialerOptions struct {
+	Ipc      string
+	Prefixes []netip.Prefix
+	Mtu      int
+	Dns      []netip.Addr
+}
+
+func NewStreamDialer(opts DialerOptions) (*StreamDialer, error) {
+	var localAddresses []netip.Addr
+	for _, prefix := range opts.Prefixes {
+		localAddresses = append(localAddresses, prefix.Addr())
+	}
+
+	tun, tnet, err := netstack.CreateNetTUN(localAddresses, opts.Dns, opts.Mtu)
+	if err != nil {
+		return nil, fmt.Errorf("failed to create network tun: %v", err)
+	}
+
+	awgLogger := device.Logger{
+		Verbosef: func(format string, args ...any) {
+		},
+		Errorf: func(format string, args ...any) {
+		},
+	}
+
+	dev := device.NewDevice(tun, conn.NewDefaultBind(), &awgLogger)
+	if err := dev.IpcSet(opts.Ipc); err != nil {
+		return nil, fmt.Errorf("failed to configure device: %v", err)
+	}
+
+	if err := dev.Up(); err != nil {
+		return nil, fmt.Errorf("failed to start awg device: %v", err)
+	}
+
+	return &StreamDialer{
+		tnet: tnet,
+	}, nil
+}
+
+var _ transport.StreamDialer = (*StreamDialer)(nil)
+
+type StreamDialer struct {
+	tnet *netstack.Net
+}
+
+func (d *StreamDialer) DialStream(ctx context.Context, raddr string) (transport.StreamConn, error) {
+	host, port, err := net.SplitHostPort(raddr)
+	if err != nil {
+		return nil, fmt.Errorf("failed to parse raddr: %v", err)
+	}
+	if l := len(host); l > 0 && host[l-1] == '.' {
+		host = host[:l-1]
+		raddr = net.JoinHostPort(host, port)
+	}
+
+	conn, err := d.tnet.DialContext(ctx, "tcp", raddr)
+	if err != nil {
+		return nil, err
+	}
+
+	return conn.(*gonet.TCPConn), nil
+}

outline/fallback.go

@@ -0,0 +1,269 @@
+package outline
+
+import (
+	"context"
+	"encoding/base64"
+	"encoding/hex"
+	"fmt"
+	"net/netip"
+	"strconv"
+	"strings"
+
+	"github.com/goccy/go-yaml"
+	"golang.getoutline.org/sdk/transport"
+	"golang.getoutline.org/sdk/x/mobileproxy"
+	"golang.getoutline.org/sdk/x/smart"
+)
+
+type DeviceConfig struct {
+	PrivateKey             string       `yaml:"private_key"`
+	Address                []string     `yaml:"address"`
+	Dns                    []string     `yaml:"dns"`
+	Mtu                    int          `yaml:"mtu,omitempty"`
+	Jc                     int          `yaml:"jc,omitempty"`
+	Jmin                   int          `yaml:"jmin,omitempty"`
+	Jmax                   int          `yaml:"jmax,omitempty"`
+	S1                     int          `yaml:"s1,omitempty"`
+	S2                     int          `yaml:"s2,omitempty"`
+	S3                     int          `yaml:"s3,omitempty"`
+	S4                     int          `yaml:"s4,omitempty"`
+	H1                     string       `yaml:"h1,omitempty"`
+	H2                     string       `yaml:"h2,omitempty"`
+	H3                     string       `yaml:"h3,omitempty"`
+	H4                     string       `yaml:"h4,omitempty"`
+	I1                     string       `yaml:"i1,omitempty"`
+	I2                     string       `yaml:"i2,omitempty"`
+	I3                     string       `yaml:"i3,omitempty"`
+	I4                     string       `yaml:"i4,omitempty"`
+	I5                     string       `yaml:"i5,omitempty"`
+	HeaderProtectionKey    string       `yaml:"header_protection_key,omitempty"`
+	ContentPaddingAddition string       `yaml:"content_padding_addition,omitempty"`
+	RekeyAfterTime         string       `yaml:"rekey_after_time,omitempty"`
+	RekeyTimeout           string       `yaml:"rekey_timeout,omitempty"`
+	RejectAfterTime        string       `yaml:"reject_after_time,omitempty"`
+	KeepaliveTimeout       string       `yaml:"keepalive_timeout,omitempty"`
+	MaxHandshakeAttempts   string       `yaml:"max_handshake_attempts,omitempty"`
+	RandomTrailers         string       `yaml:"random_trailers,omitempty"`
+	DisableCookies         string       `yaml:"disable_cookies,omitempty"`
+	Peers                  []PeerConfig `yaml:"peers,omitempty"`
+}
+
+type PeerConfig struct {
+	PublicKey                   string   `yaml:"public_key"`
+	PresharedKey                string   `yaml:"preshared_key,omitempty"`
+	Endpoint                    string   `yaml:"endpoint"`
+	AllowedIPs                  []string `yaml:"allowed_ips"`
+	PersistentKeepaliveInterval uint16   `yaml:"persistent_keepalive_interval,omitempty"`
+}
+
+func mapYamlToConfig(y smart.YAMLNode) (*DeviceConfig, error) {
+	bytes, err := yaml.Marshal(y)
+	if err != nil {
+		return nil, fmt.Errorf("failed to marshal yaml: %v", err)
+	}
+
+	var cfg DeviceConfig
+	if err = yaml.Unmarshal(bytes, &cfg); err != nil {
+		return nil, fmt.Errorf("failed to unmarshal yaml: %v", err)
+	}
+
+	return &cfg, nil
+}
+
+func genIpcString(cfg *DeviceConfig) (string, error) {
+	privateKeyBytes, err := base64.StdEncoding.DecodeString(cfg.PrivateKey)
+	if err != nil {
+		return "", fmt.Errorf("failed to decode private key: %v", err)
+	}
+
+	var b strings.Builder
+
+	b.WriteString("private_key=")
+	b.WriteString(hex.EncodeToString(privateKeyBytes))
+
+	if cfg.Jc != 0 {
+		b.WriteString("\njc=")
+		b.WriteString(strconv.Itoa(cfg.Jc))
+	}
+	if cfg.Jmin != 0 {
+		b.WriteString("\njmin=")
+		b.WriteString(strconv.Itoa(cfg.Jmin))
+	}
+	if cfg.Jmax != 0 {
+		b.WriteString("\njmax=")
+		b.WriteString(strconv.Itoa(cfg.Jmax))
+	}
+	if cfg.S1 != 0 {
+		b.WriteString("\ns1=")
+		b.WriteString(strconv.Itoa(cfg.S1))
+	}
+	if cfg.S2 != 0 {
+		b.WriteString("\ns2=")
+		b.WriteString(strconv.Itoa(cfg.S2))
+	}
+	if cfg.S3 != 0 {
+		b.WriteString("\ns3=")
+		b.WriteString(strconv.Itoa(cfg.S3))
+	}
+	if cfg.S4 != 0 {
+		b.WriteString("\ns4=")
+		b.WriteString(strconv.Itoa(cfg.S4))
+	}
+	if cfg.H1 != "" {
+		b.WriteString("\nh1=")
+		b.WriteString(cfg.H1)
+	}
+	if cfg.H2 != "" {
+		b.WriteString("\nh2=")
+		b.WriteString(cfg.H2)
+	}
+	if cfg.H3 != "" {
+		b.WriteString("\nh3=")
+		b.WriteString(cfg.H3)
+	}
+	if cfg.H4 != "" {
+		b.WriteString("\nh4=")
+		b.WriteString(cfg.H4)
+	}
+	if cfg.I1 != "" {
+		b.WriteString("\ni1=")
+		b.WriteString(cfg.I1)
+	}
+	if cfg.I2 != "" {
+		b.WriteString("\ni2=")
+		b.WriteString(cfg.I2)
+	}
+	if cfg.I3 != "" {
+		b.WriteString("\ni3=")
+		b.WriteString(cfg.I3)
+	}
+	if cfg.I4 != "" {
+		b.WriteString("\ni4=")
+		b.WriteString(cfg.I4)
+	}
+	if cfg.I5 != "" {
+		b.WriteString("\ni5=")
+		b.WriteString(cfg.I5)
+	}
+	if cfg.HeaderProtectionKey != "" {
+		b.WriteString("\nheader_protection_key=")
+		b.WriteString(cfg.HeaderProtectionKey)
+	}
+	if cfg.ContentPaddingAddition != "" {
+		b.WriteString("\ncontent_padding_addition=")
+		b.WriteString(cfg.ContentPaddingAddition)
+	}
+	if cfg.RekeyAfterTime != "" {
+		b.WriteString("\nrekey_after_time=")
+		b.WriteString(cfg.RekeyAfterTime)
+	}
+	if cfg.RekeyTimeout != "" {
+		b.WriteString("\nrekey_timeout=")
+		b.WriteString(cfg.RekeyTimeout)
+	}
+	if cfg.RejectAfterTime != "" {
+		b.WriteString("\nreject_after_time=")
+		b.WriteString(cfg.RejectAfterTime)
+	}
+	if cfg.KeepaliveTimeout != "" {
+		b.WriteString("\nkeepalive_timeout=")
+		b.WriteString(cfg.KeepaliveTimeout)
+	}
+	if cfg.MaxHandshakeAttempts != "" {
+		b.WriteString("\nmax_handshake_attempts=")
+		b.WriteString(cfg.MaxHandshakeAttempts)
+	}
+	if cfg.RandomTrailers != "" {
+		b.WriteString("\nrandom_trailers=")
+		b.WriteString(cfg.RandomTrailers)
+	}
+	if cfg.DisableCookies != "" {
+		b.WriteString("\ndisable_cookies=")
+		b.WriteString(cfg.DisableCookies)
+	}
+
+	for _, peer := range cfg.Peers {
+		publicKeyBytes, err := base64.StdEncoding.DecodeString(peer.PublicKey)
+		if err != nil {
+			return "", fmt.Errorf("failed to decode public key: %v", err)
+		}
+
+		b.WriteString("\npublic_key=")
+		b.WriteString(hex.EncodeToString(publicKeyBytes))
+
+		b.WriteString("\nendpoint=")
+		b.WriteString(peer.Endpoint)
+
+		for _, allowedIp := range peer.AllowedIPs {
+			b.WriteString("\nallowed_ip=")
+			b.WriteString(allowedIp)
+		}
+
+		if peer.PresharedKey != "" {
+			presharedKeyBytes, err := base64.StdEncoding.DecodeString(peer.PresharedKey)
+			if err != nil {
+				return "", fmt.Errorf("failed to decode preshared key: %v", err)
+			}
+
+			b.WriteString("\npreshared_key=")
+			b.WriteString(hex.EncodeToString(presharedKeyBytes))
+		}
+
+		if peer.PersistentKeepaliveInterval != 0 {
+			b.WriteString("\npersistent_keepalive_interval=")
+			b.WriteString(strconv.Itoa(int(peer.PersistentKeepaliveInterval)))
+		}
+	}
+
+	return b.String(), nil
+}
+
+func FallbackParser(ctx context.Context, y smart.YAMLNode) (transport.StreamDialer, string, error) {
+	cfg, err := mapYamlToConfig(y)
+	if err != nil {
+		return nil, "", fmt.Errorf("failed to map yaml to config: %v", err)
+	}
+
+	ipc, err := genIpcString(cfg)
+	if err != nil {
+		return nil, "", fmt.Errorf("faield to generate ipc config: %v", err)
+	}
+
+	var prefixes []netip.Prefix
+	for _, address := range cfg.Address {
+		prefix, err := netip.ParsePrefix(address)
+		if err != nil {
+			return nil, "", fmt.Errorf("failed to parse address: %v", err)
+		}
+		prefixes = append(prefixes, prefix)
+	}
+
+	var dns []netip.Addr
+	for _, saddr := range cfg.Dns {
+		addr, err := netip.ParseAddr(saddr)
+		if err != nil {
+			return nil, "", fmt.Errorf("failed to parse dns: %v", err)
+		}
+		dns = append(dns, addr)
+	}
+
+	if cfg.Mtu == 0 {
+		cfg.Mtu = 1408
+	}
+
+	dialer, err := NewStreamDialer(DialerOptions{
+		Ipc:      ipc,
+		Prefixes: prefixes,
+		Mtu:      cfg.Mtu,
+		Dns:      dns,
+	})
+	if err != nil {
+		return nil, "", fmt.Errorf("failed to create dialer: %v", err)
+	}
+
+	return dialer, ipc, nil
+}
+
+func RegisterFallbackParser(opt *mobileproxy.SmartDialerOptions, name string) {
+	opt.RegisterFallbackParser(name, FallbackParser)
+}

outline/fallback_test.go

@@ -0,0 +1,52 @@
+package outline_test
+
+import (
+	"testing"
+
+	awg "github.com/amnezia-vpn/amneziawg-go/v3/outline"
+	"golang.getoutline.org/sdk/x/mobileproxy"
+)
+
+const cfg = `
+dns:
+  - {system: {}}
+tls:
+  - ""
+fallback:
+  - awg:
+      address: [10.0.0.0/32]
+      dns: [8.8.8.8, 8.8.4.4]
+      private_key: +CdqlYvjqZ3OUr4mLWvGJo1h67CWpQwMIxA5OpyiJUM=
+      jc: 4
+      jmin: 50
+      jmax: 100
+      s1: 87
+      s2: 65
+      s3: 43
+      s4: 21
+      h1: 1000000000-1000000001
+      h2: 2000000000-2000000002
+      h3: 3000000000-3000000003
+      h4: 4000000000-4000000004
+      peers:
+        - public_key: EGxNYihRLKQ9nvdOE5j5aZ7rtw3ttzJS1xxaJpgYYHI=
+          preshared_key: 2OiSh6rP3t/g39jgJNGK70B+nize821yIFNtUqi8/XU=
+          endpoint: 123.123.123.123:51820
+          allowed_ips: [0.0.0.0/0, ::/0]
+          persistent_keepalive_interval: 25
+`
+
+var testDomains = mobileproxy.NewListFromLines("example.com")
+
+func Test_outlineIntegration(t *testing.T) {
+	opts := mobileproxy.NewSmartDialerOptions(testDomains, cfg)
+	opts.SetLogWriter(mobileproxy.NewStderrLogWriter())
+	awg.RegisterFallbackParser(opts, "awg")
+	dialer, err := opts.NewStreamDialer()
+	if err != nil {
+		t.Fatal(err)
+	}
+	if _, err = mobileproxy.RunProxy("127.0.0.1:0", dialer); err != nil {
+		t.Fatal(err)
+	}
+}

ratelimiter/ratelimiter.go

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package ratelimiter

ratelimiter/ratelimiter_test.go

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package ratelimiter

replay/replay.go

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 // Package replay implements an efficient anti-replay algorithm as specified in RFC 6479.

replay/replay_test.go

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package replay

rwcancel/rwcancel.go

@@ -2,7 +2,7 @@
 
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 // Package rwcancel implements cancelable read/write operations on
@@ -64,7 +64,7 @@ func (rw *RWCancel) ReadyRead() bool {
 
 func (rw *RWCancel) ReadyWrite() bool {
 	closeFd := int32(rw.closingReader.Fd())
-	pollFds := []unix.PollFd{{Fd: int32(rw.fd), Events: unix.POLLOUT}, {Fd: closeFd, Events: unix.POLLOUT}}
+	pollFds := []unix.PollFd{{Fd: int32(rw.fd), Events: unix.POLLOUT}, {Fd: closeFd, Events: unix.POLLIN}}
 	var err error
 	for {
 		_, err = unix.Poll(pollFds, -1)

tai64n/tai64n.go

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package tai64n

tai64n/tai64n_test.go

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package tai64n

tun/alignment_windows_test.go

@@ -1,6 +1,6 @@
 /* SPDX-License-Identifier: MIT
  *
- * Copyright (C) 2017-2023 WireGuard LLC. All Rights Reserved.
+ * Copyright (C) 2017-2025 WireGuard LLC. All Rights Reserved.
  */
 
 package tun

tun/checksum.go

@@ -1,26 +1,86 @@
 package tun
 
-import "encoding/binary"
+import (
+	"encoding/binary"
+	"math/bits"
+)
 
 // TODO: Explore SIMD and/or other assembly optimizations.
 func checksumNoFold(b []byte, initial uint64) uint64 {
-	ac := initial
-	i := 0
-	n := len(b)
-	for n >= 4 {
-		ac += uint64(binary.BigEndian.Uint32(b[i : i+4]))
-		n -= 4
-		i += 4
+	tmp := make([]byte, 8)
+	binary.NativeEndian.PutUint64(tmp, initial)
+	ac := binary.BigEndian.Uint64(tmp)
+	var carry uint64
+
+	for len(b) >= 128 {
+		ac, carry = bits.Add64(ac, binary.NativeEndian.Uint64(b[:8]), 0)
+		ac, carry = bits.Add64(ac, binary.NativeEndian.Uint64(b[8:16]), carry)
+		ac, carry = bits.Add64(ac, binary.NativeEndian.Uint64(b[16:24]), carry)
+		ac, carry = bits.Add64(ac, binary.NativeEndian.Uint64(b[24:32]), carry)
+		ac, carry = bits.Add64(ac, binary.NativeEndian.Uint64(b[32:40]), carry)
+		ac, carry = bits.Add64(ac, binary.NativeEndian.Uint64(b[40:48]), carry)
+		ac, carry = bits.Add64(ac, binary.NativeEndian.Uint64(b[48:56]), carry)
+		ac, carry = bits.Add64(ac, binary.NativeEndian.Uint64(b[56:64]), carry)
+		ac, carry = bits.Add64(ac, binary.NativeEndian.Uint64(b[64:72]), carry)
+		ac, carry = bits.Add64(ac, binary.NativeEndian.Uint64(b[72:80]), carry)
+		ac, carry = bits.Add64(ac, binary.NativeEndian.Uint64(b[80:88]), carry)
+		ac, carry = bits.Add64(ac, binary.NativeEndian.Uint64(b[88:96]), carry)
+		ac, carry = bits.Add64(ac, binary.NativeEndian.Uint64(b[96:104]), carry)
+		ac, carry = bits.Add64(ac, binary.NativeEndian.Uint64(b[104:112]), carry)
+		ac, carry = bits.Add64(ac, binary.NativeEndian.Uint64(b[112:120]), carry)
+		ac, carry = bits.Add64(ac, binary.NativeEndian.Uint64(b[120:128]), carry)
+		ac += carry
+		b = b[128:]
 	}
-	for n >= 2 {
-		ac += uint64(binary.BigEndian.Uint16(b[i : i+2]))
-		n -= 2
-		i += 2
+	if len(b) >= 64 {
+		ac, carry = bits.Add64(ac, binary.NativeEndian.Uint64(b[:8]), 0)
+		ac, carry = bits.Add64(ac, binary.NativeEndian.Uint64(b[8:16]), carry)
+		ac, carry = bits.Add64(ac, binary.NativeEndian.Uint64(b[16:24]), carry)
+		ac, carry = bits.Add64(ac, binary.NativeEndian.Uint64(b[24:32]), carry)
+		ac, carry = bits.Add64(ac, binary.NativeEndian.Uint64(b[32:40]), carry)
+		ac, carry = bits.Add64(ac, binary.NativeEndian.Uint64(b[40:48]), carry)
+		ac, carry = bits.Add64(ac, binary.NativeEndian.Uint64(b[48:56]), carry)
+		ac, carry = bits.Add64(ac, binary.NativeEndian.Uint64(b[56:64]), carry)
+		ac += carry
+		b = b[64:]
 	}
-	if n == 1 {
-		ac += uint64(b[i]) << 8
+	if len(b) >= 32 {
+		ac, carry = bits.Add64(ac, binary.NativeEndian.Uint64(b[:8]), 0)
+		ac, carry = bits.Add64(ac, binary.NativeEndian.Uint64(b[8:16]), carry)
+		ac, carry = bits.Add64(ac, binary.NativeEndian.Uint64(b[16:24]), carry)
+		ac, carry = bits.Add64(ac, binary.NativeEndian.Uint64(b[24:32]), carry)
+		ac += carry
+		b = b[32:]
 	}
-	return ac
+	if len(b) >= 16 {
+		ac, carry = bits.Add64(ac, binary.NativeEndian.Uint64(b[:8]), 0)
+		ac, carry = bits.Add64(ac, binary.NativeEndian.Uint64(b[8:16]), carry)
+		ac += carry
+		b = b[16:]
+	}
+	if len(b) >= 8 {
+		ac, carry = bits.Add64(ac, binary.NativeEndian.Uint64(b[:8]), 0)
+		ac += carry
+		b = b[8:]
+	}
+	if len(b) >= 4 {
+		ac, carry = bits.Add64(ac, uint64(binary.NativeEndian.Uint32(b[:4])), 0)
+		ac += carry
+		b = b[4:]
+	}
+	if len(b) >= 2 {
+		ac, carry = bits.Add64(ac, uint64(binary.NativeEndian.Uint16(b[:2])), 0)
+		ac += carry
+		b = b[2:]
+	}
+	if len(b) == 1 {
+		tmp := binary.NativeEndian.Uint16([]byte{b[0], 0})
+		ac, carry = bits.Add64(ac, uint64(tmp), 0)
+		ac += carry
+	}
+
+	binary.NativeEndian.PutUint64(tmp, ac)
+	return binary.BigEndian.Uint64(tmp)
 }
 
 func checksum(b []byte, initial uint64) uint16 {

tun/checksum_test.go

@@ -0,0 +1,98 @@
+package tun
+
+import (
+	"encoding/binary"
+	"fmt"
+	"math/rand"
+	"testing"
+
+	"golang.org/x/sys/unix"
+)
+
+func checksumRef(b []byte, initial uint16) uint16 {
+	ac := uint64(initial)
+
+	for len(b) >= 2 {
+		ac += uint64(binary.BigEndian.Uint16(b))
+		b = b[2:]
+	}
+	if len(b) == 1 {
+		ac += uint64(b[0]) << 8
+	}
+
+	for (ac >> 16) > 0 {
+		ac = (ac >> 16) + (ac & 0xffff)
+	}
+	return uint16(ac)
+}
+
+func pseudoHeaderChecksumRefNoFold(protocol uint8, srcAddr, dstAddr []byte, totalLen uint16) uint16 {
+	sum := checksumRef(srcAddr, 0)
+	sum = checksumRef(dstAddr, sum)
+	sum = checksumRef([]byte{0, protocol}, sum)
+	tmp := make([]byte, 2)
+	binary.BigEndian.PutUint16(tmp, totalLen)
+	return checksumRef(tmp, sum)
+}
+
+func TestChecksum(t *testing.T) {
+	for length := 0; length <= 9001; length++ {
+		buf := make([]byte, length)
+		rng := rand.New(rand.NewSource(1))
+		rng.Read(buf)
+		csum := checksum(buf, 0x1234)
+		csumRef := checksumRef(buf, 0x1234)
+		if csum != csumRef {
+			t.Error("Expected checksum", csumRef, "got", csum)
+		}
+	}
+}
+
+func TestPseudoHeaderChecksum(t *testing.T) {
+	for _, addrLen := range []int{4, 16} {
+		for length := 0; length <= 9001; length++ {
+			srcAddr := make([]byte, addrLen)
+			dstAddr := make([]byte, addrLen)
+			buf := make([]byte, length)
+			rng := rand.New(rand.NewSource(1))
+			rng.Read(srcAddr)
+			rng.Read(dstAddr)
+			rng.Read(buf)
+			phSum := pseudoHeaderChecksumNoFold(unix.IPPROTO_TCP, srcAddr, dstAddr, uint16(length))
+			csum := checksum(buf, phSum)
+			phSumRef := pseudoHeaderChecksumRefNoFold(unix.IPPROTO_TCP, srcAddr, dstAddr, uint16(length))
+			csumRef := checksumRef(buf, phSumRef)
+			if csum != csumRef {
+				t.Error("Expected checksumRef", csumRef, "got", csum)
+			}
+		}
+	}
+}
+
+func BenchmarkChecksum(b *testing.B) {
+	lengths := []int{
+		64,
+		128,
+		256,
+		512,
+		1024,
+		1500,
+		2048,
+		4096,
+		8192,
+		9000,
+		9001,
+	}
+
+	for _, length := range lengths {
+		b.Run(fmt.Sprintf("%d", length), func(b *testing.B) {
+			buf := make([]byte, length)
+			rng := rand.New(rand.NewSource(1))
+			rng.Read(buf)
+			b.ResetTimer()
+			for i := 0; i < b.N; i++ {
+				checksum(buf, 0)
+			}
+		})
+	}
+}