Add dependencies/vendor (whatsapp)

vendor/go.mau.fi/whatsmeow/socket/noisesocket.go

@@ -0,0 +1,104 @@
+// Copyright (c) 2021 Tulir Asokan
+//
+// This Source Code Form is subject to the terms of the Mozilla Public
+// License, v. 2.0. If a copy of the MPL was not distributed with this
+// file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+package socket
+
+import (
+	"context"
+	"crypto/cipher"
+	"encoding/binary"
+	"sync"
+	"sync/atomic"
+
+	"github.com/gorilla/websocket"
+)
+
+type NoiseSocket struct {
+	fs           *FrameSocket
+	onFrame      FrameHandler
+	writeKey     cipher.AEAD
+	readKey      cipher.AEAD
+	writeCounter uint32
+	readCounter  uint32
+	writeLock    sync.Mutex
+	destroyed    uint32
+	stopConsumer chan struct{}
+}
+
+type DisconnectHandler func(socket *NoiseSocket, remote bool)
+type FrameHandler func([]byte)
+
+func newNoiseSocket(fs *FrameSocket, writeKey, readKey cipher.AEAD, frameHandler FrameHandler, disconnectHandler DisconnectHandler) (*NoiseSocket, error) {
+	ns := &NoiseSocket{
+		fs:           fs,
+		writeKey:     writeKey,
+		readKey:      readKey,
+		onFrame:      frameHandler,
+		stopConsumer: make(chan struct{}),
+	}
+	fs.OnDisconnect = func(remote bool) {
+		disconnectHandler(ns, remote)
+	}
+	go ns.consumeFrames(fs.ctx, fs.Frames)
+	return ns, nil
+}
+
+func (ns *NoiseSocket) consumeFrames(ctx context.Context, frames <-chan []byte) {
+	ctxDone := ctx.Done()
+	for {
+		select {
+		case frame := <-frames:
+			ns.receiveEncryptedFrame(frame)
+		case <-ctxDone:
+			return
+		case <-ns.stopConsumer:
+			return
+		}
+	}
+}
+
+func generateIV(count uint32) []byte {
+	iv := make([]byte, 12)
+	binary.BigEndian.PutUint32(iv[8:], count)
+	return iv
+}
+
+func (ns *NoiseSocket) Context() context.Context {
+	return ns.fs.Context()
+}
+
+func (ns *NoiseSocket) Stop(disconnect bool) {
+	if atomic.CompareAndSwapUint32(&ns.destroyed, 0, 1) {
+		close(ns.stopConsumer)
+		ns.fs.OnDisconnect = nil
+		if disconnect {
+			ns.fs.Close(websocket.CloseNormalClosure)
+		}
+	}
+}
+
+func (ns *NoiseSocket) SendFrame(plaintext []byte) error {
+	ns.writeLock.Lock()
+	ciphertext := ns.writeKey.Seal(nil, generateIV(ns.writeCounter), plaintext, nil)
+	ns.writeCounter++
+	err := ns.fs.SendFrame(ciphertext)
+	ns.writeLock.Unlock()
+	return err
+}
+
+func (ns *NoiseSocket) receiveEncryptedFrame(ciphertext []byte) {
+	count := atomic.AddUint32(&ns.readCounter, 1) - 1
+	plaintext, err := ns.readKey.Open(nil, generateIV(count), ciphertext, nil)
+	if err != nil {
+		ns.fs.log.Warnf("Failed to decrypt frame: %v", err)
+		return
+	}
+	ns.onFrame(plaintext)
+}
+
+func (ns *NoiseSocket) IsConnected() bool {
+	return ns.fs.IsConnected()
+}