1 files changed, 383 insertions, 0 deletions
diff --git a/vendor/go.mau.fi/whatsmeow/message.go b/vendor/go.mau.fi/whatsmeow/message.go
new file mode 100644
index 00000000..f8906142
--- /dev/null
+++ b/vendor/go.mau.fi/whatsmeow/message.go
@@ -0,0 +1,383 @@
+// 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 whatsmeow
+
+import (
+	"bytes"
+	"compress/zlib"
+	"crypto/rand"
+	"errors"
+	"fmt"
+	"io"
+	"strconv"
+	"time"
+
+	"go.mau.fi/libsignal/signalerror"
+	"google.golang.org/protobuf/proto"
+
+	"go.mau.fi/libsignal/groups"
+	"go.mau.fi/libsignal/protocol"
+	"go.mau.fi/libsignal/session"
+
+	"go.mau.fi/whatsmeow/appstate"
+	waBinary "go.mau.fi/whatsmeow/binary"
+	waProto "go.mau.fi/whatsmeow/binary/proto"
+	"go.mau.fi/whatsmeow/store"
+	"go.mau.fi/whatsmeow/types"
+	"go.mau.fi/whatsmeow/types/events"
+)
+
+var pbSerializer = store.SignalProtobufSerializer
+
+func (cli *Client) handleEncryptedMessage(node *waBinary.Node) {
+	info, err := cli.parseMessageInfo(node)
+	if err != nil {
+		cli.Log.Warnf("Failed to parse message: %v", err)
+	} else {
+		if len(info.PushName) > 0 && info.PushName != "-" {
+			go cli.updatePushName(info.Sender, info, info.PushName)
+		}
+		cli.decryptMessages(info, node)
+	}
+}
+
+func (cli *Client) parseMessageSource(node *waBinary.Node) (source types.MessageSource, err error) {
+	from, ok := node.Attrs["from"].(types.JID)
+	if !ok {
+		err = fmt.Errorf("didn't find valid `from` attribute in message")
+	} else if from.Server == types.GroupServer || from.Server == types.BroadcastServer {
+		source.IsGroup = true
+		source.Chat = from
+		sender, ok := node.Attrs["participant"].(types.JID)
+		if !ok {
+			err = fmt.Errorf("didn't find valid `participant` attribute in group message")
+		} else {
+			source.Sender = sender
+			if source.Sender.User == cli.Store.ID.User {
+				source.IsFromMe = true
+			}
+		}
+		if from.Server == types.BroadcastServer {
+			recipient, ok := node.Attrs["recipient"].(types.JID)
+			if ok {
+				source.BroadcastListOwner = recipient
+			}
+		}
+	} else if from.User == cli.Store.ID.User {
+		source.IsFromMe = true
+		source.Sender = from
+		recipient, ok := node.Attrs["recipient"].(types.JID)
+		if !ok {
+			source.Chat = from.ToNonAD()
+		} else {
+			source.Chat = recipient
+		}
+	} else {
+		source.Chat = from.ToNonAD()
+		source.Sender = from
+	}
+	return
+}
+
+func (cli *Client) parseMessageInfo(node *waBinary.Node) (*types.MessageInfo, error) {
+	var info types.MessageInfo
+	var err error
+	var ok bool
+	info.MessageSource, err = cli.parseMessageSource(node)
+	if err != nil {
+		return nil, err
+	}
+	info.ID, ok = node.Attrs["id"].(string)
+	if !ok {
+		return nil, fmt.Errorf("didn't find valid `id` attribute in message")
+	}
+	ts, ok := node.Attrs["t"].(string)
+	if !ok {
+		return nil, fmt.Errorf("didn't find valid `t` (timestamp) attribute in message")
+	}
+	tsInt, err := strconv.ParseInt(ts, 10, 64)
+	if err != nil {
+		return nil, fmt.Errorf("didn't find valid `t` (timestamp) attribute in message: %w", err)
+	}
+	info.Timestamp = time.Unix(tsInt, 0)
+
+	info.PushName, _ = node.Attrs["notify"].(string)
+	info.Category, _ = node.Attrs["category"].(string)
+
+	return &info, nil
+}
+
+func (cli *Client) decryptMessages(info *types.MessageInfo, node *waBinary.Node) {
+	go cli.sendAck(node)
+	if len(node.GetChildrenByTag("unavailable")) == len(node.GetChildren()) {
+		cli.Log.Warnf("Unavailable message %s from %s", info.ID, info.SourceString())
+		go cli.sendRetryReceipt(node, true)
+		cli.dispatchEvent(&events.UndecryptableMessage{Info: *info, IsUnavailable: true})
+		return
+	}
+	children := node.GetChildren()
+	cli.Log.Debugf("Decrypting %d messages from %s", len(children), info.SourceString())
+	handled := false
+	for _, child := range children {
+		if child.Tag != "enc" {
+			continue
+		}
+		encType, ok := child.Attrs["type"].(string)
+		if !ok {
+			continue
+		}
+		var decrypted []byte
+		var err error
+		if encType == "pkmsg" || encType == "msg" {
+			decrypted, err = cli.decryptDM(&child, info.Sender, encType == "pkmsg")
+		} else if info.IsGroup && encType == "skmsg" {
+			decrypted, err = cli.decryptGroupMsg(&child, info.Sender, info.Chat)
+		} else {
+			cli.Log.Warnf("Unhandled encrypted message (type %s) from %s", encType, info.SourceString())
+			continue
+		}
+		if err != nil {
+			cli.Log.Warnf("Error decrypting message from %s: %v", info.SourceString(), err)
+			go cli.sendRetryReceipt(node, false)
+			cli.dispatchEvent(&events.UndecryptableMessage{Info: *info, IsUnavailable: false})
+			return
+		}
+
+		var msg waProto.Message
+		err = proto.Unmarshal(decrypted, &msg)
+		if err != nil {
+			cli.Log.Warnf("Error unmarshaling decrypted message from %s: %v", info.SourceString(), err)
+			continue
+		}
+
+		cli.handleDecryptedMessage(info, &msg)
+		handled = true
+	}
+	if handled {
+		go cli.sendMessageReceipt(info)
+	}
+}
+
+func (cli *Client) decryptDM(child *waBinary.Node, from types.JID, isPreKey bool) ([]byte, error) {
+	content, _ := child.Content.([]byte)
+
+	builder := session.NewBuilderFromSignal(cli.Store, from.SignalAddress(), pbSerializer)
+	cipher := session.NewCipher(builder, from.SignalAddress())
+	var plaintext []byte
+	if isPreKey {
+		preKeyMsg, err := protocol.NewPreKeySignalMessageFromBytes(content, pbSerializer.PreKeySignalMessage, pbSerializer.SignalMessage)
+		if err != nil {
+			return nil, fmt.Errorf("failed to parse prekey message: %w", err)
+		}
+		plaintext, _, err = cipher.DecryptMessageReturnKey(preKeyMsg)
+		if errors.Is(err, signalerror.ErrUntrustedIdentity) {
+			cli.Log.Warnf("Got %v error while trying to decrypt prekey message from %s, clearing stored identity and retrying", err, from)
+			err = cli.Store.Identities.DeleteIdentity(from.SignalAddress().String())
+			if err != nil {
+				cli.Log.Warnf("Failed to delete identity of %s from store after decryption error: %v", from, err)
+			}
+			err = cli.Store.Sessions.DeleteSession(from.SignalAddress().String())
+			if err != nil {
+				cli.Log.Warnf("Failed to delete session with %s from store after decryption error: %v", from, err)
+			}
+			cli.dispatchEvent(&events.IdentityChange{JID: from, Timestamp: time.Now(), Implicit: true})
+			plaintext, _, err = cipher.DecryptMessageReturnKey(preKeyMsg)
+		}
+		if err != nil {
+			return nil, fmt.Errorf("failed to decrypt prekey message: %w", err)
+		}
+	} else {
+		msg, err := protocol.NewSignalMessageFromBytes(content, pbSerializer.SignalMessage)
+		if err != nil {
+			return nil, fmt.Errorf("failed to parse normal message: %w", err)
+		}
+		plaintext, err = cipher.Decrypt(msg)
+		if err != nil {
+			return nil, fmt.Errorf("failed to decrypt normal message: %w", err)
+		}
+	}
+	return unpadMessage(plaintext)
+}
+
+func (cli *Client) decryptGroupMsg(child *waBinary.Node, from types.JID, chat types.JID) ([]byte, error) {
+	content, _ := child.Content.([]byte)
+
+	senderKeyName := protocol.NewSenderKeyName(chat.String(), from.SignalAddress())
+	builder := groups.NewGroupSessionBuilder(cli.Store, pbSerializer)
+	cipher := groups.NewGroupCipher(builder, senderKeyName, cli.Store)
+	msg, err := protocol.NewSenderKeyMessageFromBytes(content, pbSerializer.SenderKeyMessage)
+	if err != nil {
+		return nil, fmt.Errorf("failed to parse group message: %w", err)
+	}
+	plaintext, err := cipher.Decrypt(msg)
+	if err != nil {
+		return nil, fmt.Errorf("failed to decrypt group message: %w", err)
+	}
+	return unpadMessage(plaintext)
+}
+
+const checkPadding = true
+
+func isValidPadding(plaintext []byte) bool {
+	lastByte := plaintext[len(plaintext)-1]
+	expectedPadding := bytes.Repeat([]byte{lastByte}, int(lastByte))
+	return bytes.HasSuffix(plaintext, expectedPadding)
+}
+
+func unpadMessage(plaintext []byte) ([]byte, error) {
+	if checkPadding && !isValidPadding(plaintext) {
+		return nil, fmt.Errorf("plaintext doesn't have expected padding")
+	}
+	return plaintext[:len(plaintext)-int(plaintext[len(plaintext)-1])], nil
+}
+
+func padMessage(plaintext []byte) []byte {
+	var pad [1]byte
+	_, err := rand.Read(pad[:])
+	if err != nil {
+		panic(err)
+	}
+	pad[0] &= 0xf
+	if pad[0] == 0 {
+		pad[0] = 0xf
+	}
+	plaintext = append(plaintext, bytes.Repeat(pad[:], int(pad[0]))...)
+	return plaintext
+}
+
+func (cli *Client) handleSenderKeyDistributionMessage(chat, from types.JID, rawSKDMsg *waProto.SenderKeyDistributionMessage) {
+	builder := groups.NewGroupSessionBuilder(cli.Store, pbSerializer)
+	senderKeyName := protocol.NewSenderKeyName(chat.String(), from.SignalAddress())
+	sdkMsg, err := protocol.NewSenderKeyDistributionMessageFromBytes(rawSKDMsg.AxolotlSenderKeyDistributionMessage, pbSerializer.SenderKeyDistributionMessage)
+	if err != nil {
+		cli.Log.Errorf("Failed to parse sender key distribution message from %s for %s: %v", from, chat, err)
+		return
+	}
+	builder.Process(senderKeyName, sdkMsg)
+	cli.Log.Debugf("Processed sender key distribution message from %s in %s", senderKeyName.Sender().String(), senderKeyName.GroupID())
+}
+
+func (cli *Client) handleHistorySyncNotification(notif *waProto.HistorySyncNotification) {
+	var historySync waProto.HistorySync
+	if data, err := cli.Download(notif); err != nil {
+		cli.Log.Errorf("Failed to download history sync data: %v", err)
+	} else if reader, err := zlib.NewReader(bytes.NewReader(data)); err != nil {
+		cli.Log.Errorf("Failed to create zlib reader for history sync data: %v", err)
+	} else if rawData, err := io.ReadAll(reader); err != nil {
+		cli.Log.Errorf("Failed to decompress history sync data: %v", err)
+	} else if err = proto.Unmarshal(rawData, &historySync); err != nil {
+		cli.Log.Errorf("Failed to unmarshal history sync data: %v", err)
+	} else {
+		cli.Log.Debugf("Received history sync")
+		if historySync.GetSyncType() == waProto.HistorySync_PUSH_NAME {
+			go cli.handleHistoricalPushNames(historySync.GetPushnames())
+		}
+		cli.dispatchEvent(&events.HistorySync{
+			Data: &historySync,
+		})
+	}
+}
+
+func (cli *Client) handleAppStateSyncKeyShare(keys *waProto.AppStateSyncKeyShare) {
+	for _, key := range keys.GetKeys() {
+		marshaledFingerprint, err := proto.Marshal(key.GetKeyData().GetFingerprint())
+		if err != nil {
+			cli.Log.Errorf("Failed to marshal fingerprint of app state sync key %X", key.GetKeyId().GetKeyId())
+			continue
+		}
+		err = cli.Store.AppStateKeys.PutAppStateSyncKey(key.GetKeyId().GetKeyId(), store.AppStateSyncKey{
+			Data:        key.GetKeyData().GetKeyData(),
+			Fingerprint: marshaledFingerprint,
+			Timestamp:   key.GetKeyData().GetTimestamp(),
+		})
+		if err != nil {
+			cli.Log.Errorf("Failed to store app state sync key %X", key.GetKeyId().GetKeyId())
+			continue
+		}
+		cli.Log.Debugf("Received app state sync key %X", key.GetKeyId().GetKeyId())
+	}
+
+	for _, name := range appstate.AllPatchNames {
+		err := cli.FetchAppState(name, false, true)
+		if err != nil {
+			cli.Log.Errorf("Failed to do initial fetch of app state %s: %v", name, err)
+		}
+	}
+}
+
+func (cli *Client) handleProtocolMessage(info *types.MessageInfo, msg *waProto.Message) {
+	protoMsg := msg.GetProtocolMessage()
+
+	if protoMsg.GetHistorySyncNotification() != nil && info.IsFromMe {
+		cli.handleHistorySyncNotification(protoMsg.HistorySyncNotification)
+		cli.sendProtocolMessageReceipt(info.ID, "hist_sync")
+	}
+
+	if protoMsg.GetAppStateSyncKeyShare() != nil && info.IsFromMe {
+		cli.handleAppStateSyncKeyShare(protoMsg.AppStateSyncKeyShare)
+	}
+
+	if info.Category == "peer" {
+		cli.sendProtocolMessageReceipt(info.ID, "peer_msg")
+	}
+}
+
+func (cli *Client) handleDecryptedMessage(info *types.MessageInfo, msg *waProto.Message) {
+	evt := &events.Message{Info: *info, RawMessage: msg}
+
+	// First unwrap device sent messages
+	if msg.GetDeviceSentMessage().GetMessage() != nil {
+		msg = msg.GetDeviceSentMessage().GetMessage()
+		evt.Info.DeviceSentMeta = &types.DeviceSentMeta{
+			DestinationJID: msg.GetDeviceSentMessage().GetDestinationJid(),
+			Phash:          msg.GetDeviceSentMessage().GetPhash(),
+		}
+	}
+
+	if msg.GetSenderKeyDistributionMessage() != nil {
+		if !info.IsGroup {
+			cli.Log.Warnf("Got sender key distribution message in non-group chat from", info.Sender)
+		} else {
+			cli.handleSenderKeyDistributionMessage(info.Chat, info.Sender, msg.SenderKeyDistributionMessage)
+		}
+	}
+	if msg.GetProtocolMessage() != nil {
+		go cli.handleProtocolMessage(info, msg)
+	}
+
+	// Unwrap ephemeral and view-once messages
+	// Hopefully sender key distribution messages and protocol messages can't be inside ephemeral messages
+	if msg.GetEphemeralMessage().GetMessage() != nil {
+		msg = msg.GetEphemeralMessage().GetMessage()
+		evt.IsEphemeral = true
+	}
+	if msg.GetViewOnceMessage().GetMessage() != nil {
+		msg = msg.GetViewOnceMessage().GetMessage()
+		evt.IsViewOnce = true
+	}
+	evt.Message = msg
+
+	cli.dispatchEvent(evt)
+}
+
+func (cli *Client) sendProtocolMessageReceipt(id, msgType string) {
+	if len(id) == 0 {
+		return
+	}
+	err := cli.sendNode(waBinary.Node{
+		Tag: "receipt",
+		Attrs: waBinary.Attrs{
+			"id":   id,
+			"type": msgType,
+			"to":   types.NewJID(cli.Store.ID.User, types.LegacyUserServer),
+		},
+		Content: nil,
+	})
+	if err != nil {
+		cli.Log.Warnf("Failed to send acknowledgement for protocol message %s: %v", id, err)
+	}
+}