755 lines
27 KiB
C++
755 lines
27 KiB
C++
#include "EncryptedConnection.h"
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#include "CryptoHelper.h"
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#include "rtc_base/logging.h"
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#include "rtc_base/byte_buffer.h"
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#include "rtc_base/time_utils.h"
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namespace tgcalls {
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namespace {
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constexpr auto kSingleMessagePacketSeqBit = (uint32_t(1) << 31);
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constexpr auto kMessageRequiresAckSeqBit = (uint32_t(1) << 30);
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constexpr auto kMaxAllowedCounter = std::numeric_limits<uint32_t>::max()
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& ~kSingleMessagePacketSeqBit
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& ~kMessageRequiresAckSeqBit;
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static_assert(kMaxAllowedCounter < kSingleMessagePacketSeqBit, "bad");
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static_assert(kMaxAllowedCounter < kMessageRequiresAckSeqBit, "bad");
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constexpr auto kAckSerializedSize = sizeof(uint32_t) + sizeof(uint8_t);
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constexpr auto kNotAckedMessagesLimit = 64 * 1024;
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constexpr auto kMaxIncomingPacketSize = 128 * 1024; // don't try decrypting more
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constexpr auto kKeepIncomingCountersCount = 64;
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constexpr auto kMaxFullPacketSize = 1500; // IP_PACKET_SIZE from webrtc.
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// Max seen turn_overhead is around 36.
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constexpr auto kMaxOuterPacketSize = kMaxFullPacketSize - 48;
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constexpr auto kMaxSignalingPacketSize = 16 * 1024;
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constexpr auto kServiceCauseAcks = 1;
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constexpr auto kServiceCauseResend = 2;
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static constexpr uint8_t kAckId = uint8_t(-1);
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static constexpr uint8_t kEmptyId = uint8_t(-2);
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static constexpr uint8_t kCustomId = uint8_t(127);
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void AppendSeq(rtc::CopyOnWriteBuffer &buffer, uint32_t seq) {
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const auto bytes = rtc::HostToNetwork32(seq);
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buffer.AppendData(reinterpret_cast<const char*>(&bytes), sizeof(bytes));
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}
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void WriteSeq(void *bytes, uint32_t seq) {
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*reinterpret_cast<uint32_t*>(bytes) = rtc::HostToNetwork32(seq);
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}
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uint32_t ReadSeq(const void *bytes) {
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return rtc::NetworkToHost32(*reinterpret_cast<const uint32_t*>(bytes));
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}
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uint32_t CounterFromSeq(uint32_t seq) {
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return seq & ~kSingleMessagePacketSeqBit & ~kMessageRequiresAckSeqBit;
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}
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absl::nullopt_t LogError(
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const char *message,
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const std::string &additional = std::string()) {
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RTC_LOG(LS_ERROR) << "ERROR! " << message << additional;
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return absl::nullopt;
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}
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bool ConstTimeIsDifferent(const void *a, const void *b, size_t size) {
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auto ca = reinterpret_cast<const char*>(a);
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auto cb = reinterpret_cast<const char*>(b);
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volatile auto different = false;
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for (const auto ce = ca + size; ca != ce; ++ca, ++cb) {
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different = different | (*ca != *cb);
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}
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return different;
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}
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rtc::CopyOnWriteBuffer SerializeRawMessageWithSeq(
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const rtc::CopyOnWriteBuffer &message,
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uint32_t seq,
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bool singleMessagePacket) {
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rtc::ByteBufferWriter writer;
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writer.WriteUInt32(seq);
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writer.WriteUInt8(kCustomId);
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writer.WriteUInt32((uint32_t)message.size());
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writer.WriteBytes((const char *)message.data(), message.size());
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auto result = rtc::CopyOnWriteBuffer();
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result.AppendData(writer.Data(), writer.Length());
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return result;
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}
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} // namespace
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EncryptedConnection::EncryptedConnection(
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Type type,
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const EncryptionKey &key,
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std::function<void(int delayMs, int cause)> requestSendService) :
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_type(type),
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_key(key),
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_delayIntervals(DelayIntervalsByType(type)),
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_requestSendService(std::move(requestSendService)) {
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assert(_key.value != nullptr);
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}
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absl::optional<rtc::CopyOnWriteBuffer> EncryptedConnection::encryptRawPacket(rtc::CopyOnWriteBuffer const &buffer) {
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auto seq = ++_counter;
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rtc::ByteBufferWriter writer;
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writer.WriteUInt32(seq);
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auto result = rtc::CopyOnWriteBuffer();
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result.AppendData(writer.Data(), writer.Length());
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result.AppendData(buffer);
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auto encryptedPacket = encryptPrepared(result);
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rtc::CopyOnWriteBuffer encryptedBuffer;
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encryptedBuffer.AppendData(encryptedPacket.bytes.data(), encryptedPacket.bytes.size());
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return encryptedBuffer;
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}
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absl::optional<rtc::CopyOnWriteBuffer> EncryptedConnection::decryptRawPacket(rtc::CopyOnWriteBuffer const &buffer) {
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if (buffer.size() < 21 || buffer.size() > kMaxIncomingPacketSize) {
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return absl::nullopt;
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}
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const auto x = (_key.isOutgoing ? 8 : 0) + (_type == Type::Signaling ? 128 : 0);
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const auto key = _key.value->data();
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const auto msgKey = reinterpret_cast<const uint8_t*>(buffer.data());
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const auto encryptedData = msgKey + 16;
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const auto dataSize = buffer.size() - 16;
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auto aesKeyIv = PrepareAesKeyIv(key, msgKey, x);
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auto decryptionBuffer = rtc::Buffer(dataSize);
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AesProcessCtr(
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MemorySpan{ encryptedData, dataSize },
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decryptionBuffer.data(),
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std::move(aesKeyIv));
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const auto msgKeyLarge = ConcatSHA256(
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MemorySpan{ key + 88 + x, 32 },
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MemorySpan{ decryptionBuffer.data(), decryptionBuffer.size() });
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if (ConstTimeIsDifferent(msgKeyLarge.data() + 8, msgKey, 16)) {
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return absl::nullopt;
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}
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const auto incomingSeq = ReadSeq(decryptionBuffer.data());
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const auto incomingCounter = CounterFromSeq(incomingSeq);
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if (!registerIncomingCounter(incomingCounter)) {
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// We've received that packet already.
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return absl::nullopt;
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}
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rtc::CopyOnWriteBuffer resultBuffer;
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resultBuffer.AppendData(decryptionBuffer.data() + 4, decryptionBuffer.size() - 4);
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return resultBuffer;
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}
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auto EncryptedConnection::prepareForSending(const Message &message)
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-> absl::optional<EncryptedPacket> {
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const auto messageRequiresAck = absl::visit([](const auto &data) {
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return std::decay_t<decltype(data)>::kRequiresAck;
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}, message.data);
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// If message requires ack, then we can't serialize it as a single
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// message packet, because later it may be sent as a part of big packet.
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const auto singleMessagePacket = !haveAdditionalMessages() && !messageRequiresAck;
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const auto maybeSeq = computeNextSeq(messageRequiresAck, singleMessagePacket);
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if (!maybeSeq) {
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return absl::nullopt;
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}
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const auto seq = *maybeSeq;
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auto serialized = SerializeMessageWithSeq(message, seq, singleMessagePacket);
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return prepareForSendingMessageInternal(serialized, seq, messageRequiresAck);
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}
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absl::optional<EncryptedConnection::EncryptedPacket> EncryptedConnection::prepareForSendingRawMessage(rtc::CopyOnWriteBuffer &message, bool messageRequiresAck) {
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// If message requires ack, then we can't serialize it as a single
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// message packet, because later it may be sent as a part of big packet.
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const auto singleMessagePacket = !haveAdditionalMessages() && !messageRequiresAck;
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const auto maybeSeq = computeNextSeq(messageRequiresAck, singleMessagePacket);
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if (!maybeSeq) {
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return absl::nullopt;
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}
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const auto seq = *maybeSeq;
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auto serialized = SerializeRawMessageWithSeq(message, seq, singleMessagePacket);
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return prepareForSendingMessageInternal(serialized, seq, messageRequiresAck);
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}
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absl::optional<EncryptedConnection::EncryptedPacket> EncryptedConnection::prepareForSendingMessageInternal(rtc::CopyOnWriteBuffer &serialized, uint32_t seq, bool messageRequiresAck) {
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if (!enoughSpaceInPacket(serialized, 0)) {
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return LogError("Too large packet: ", std::to_string(serialized.size()));
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}
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const auto notYetAckedCopy = messageRequiresAck
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? serialized
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: rtc::CopyOnWriteBuffer();
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if (!messageRequiresAck) {
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appendAdditionalMessages(serialized);
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return encryptPrepared(serialized);
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}
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const auto type = uint8_t(serialized.cdata()[4]);
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const auto sendEnqueued = !_myNotYetAckedMessages.empty();
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if (sendEnqueued) {
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// All requiring ack messages should always be sent in order within
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// one packet, starting with the least not-yet-acked one.
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// So if we still have those, we send an empty message with all
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// requiring ack messages that will fit in correct order.
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RTC_LOG(LS_INFO) << logHeader()
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<< "Enqueue SEND:type" << type << "#" << CounterFromSeq(seq);
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} else {
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RTC_LOG(LS_INFO) << logHeader()
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<< "Add SEND:type" << type << "#" << CounterFromSeq(seq);
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appendAdditionalMessages(serialized);
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}
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_myNotYetAckedMessages.push_back({ notYetAckedCopy, rtc::TimeMillis() });
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if (!sendEnqueued) {
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return encryptPrepared(serialized);
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}
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for (auto &queued : _myNotYetAckedMessages) {
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queued.lastSent = 0;
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}
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return prepareForSendingService(0);
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}
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auto EncryptedConnection::prepareForSendingService(int cause)
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-> absl::optional<EncryptedPacket> {
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if (cause == kServiceCauseAcks) {
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_sendAcksTimerActive = false;
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} else if (cause == kServiceCauseResend) {
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_resendTimerActive = false;
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}
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if (!haveAdditionalMessages()) {
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return absl::nullopt;
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}
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const auto messageRequiresAck = false;
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const auto singleMessagePacket = false;
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const auto seq = computeNextSeq(messageRequiresAck, singleMessagePacket);
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if (!seq) {
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return absl::nullopt;
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}
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auto serialized = SerializeEmptyMessageWithSeq(*seq);
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assert(enoughSpaceInPacket(serialized, 0));
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RTC_LOG(LS_INFO) << logHeader()
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<< "SEND:empty#" << CounterFromSeq(*seq);
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appendAdditionalMessages(serialized);
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return encryptPrepared(serialized);
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}
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bool EncryptedConnection::haveAdditionalMessages() const {
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return !_myNotYetAckedMessages.empty() || !_acksToSendSeqs.empty();
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}
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absl::optional<uint32_t> EncryptedConnection::computeNextSeq(
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bool messageRequiresAck,
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bool singleMessagePacket) {
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if (messageRequiresAck && _myNotYetAckedMessages.size() >= kNotAckedMessagesLimit) {
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return LogError("Too many not ACKed messages.");
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} else if (_counter == kMaxAllowedCounter) {
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return LogError("Outgoing packet limit reached.");
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}
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return (++_counter)
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| (singleMessagePacket ? kSingleMessagePacketSeqBit : 0)
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| (messageRequiresAck ? kMessageRequiresAckSeqBit : 0);
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}
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size_t EncryptedConnection::packetLimit() const {
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switch (_type) {
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case Type::Signaling:
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return kMaxSignalingPacketSize;
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default:
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return kMaxOuterPacketSize;
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}
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}
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bool EncryptedConnection::enoughSpaceInPacket(const rtc::CopyOnWriteBuffer &buffer, size_t amount) const {
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const auto limit = packetLimit();
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return (amount < limit)
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&& (16 + buffer.size() + amount <= limit);
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}
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void EncryptedConnection::appendAcksToSend(rtc::CopyOnWriteBuffer &buffer) {
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auto i = _acksToSendSeqs.begin();
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while ((i != _acksToSendSeqs.end())
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&& enoughSpaceInPacket(
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buffer,
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kAckSerializedSize)) {
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RTC_LOG(LS_INFO) << logHeader()
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<< "Add ACK#" << CounterFromSeq(*i);
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AppendSeq(buffer, *i);
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buffer.AppendData(&kAckId, 1);
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++i;
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}
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_acksToSendSeqs.erase(_acksToSendSeqs.begin(), i);
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for (const auto seq : _acksToSendSeqs) {
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RTC_LOG(LS_INFO) << logHeader()
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<< "Skip ACK#" << CounterFromSeq(seq)
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<< " (no space, length: " << kAckSerializedSize << ", already: " << buffer.size() << ")";
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}
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}
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size_t EncryptedConnection::fullNotAckedLength() const {
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assert(_myNotYetAckedMessages.size() < kNotAckedMessagesLimit);
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auto result = size_t();
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for (const auto &message : _myNotYetAckedMessages) {
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result += message.data.size();
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}
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return result;
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}
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void EncryptedConnection::appendAdditionalMessages(rtc::CopyOnWriteBuffer &buffer) {
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appendAcksToSend(buffer);
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if (_myNotYetAckedMessages.empty()) {
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return;
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}
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const auto now = rtc::TimeMillis();
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for (auto &resending : _myNotYetAckedMessages) {
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const auto sent = resending.lastSent;
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const auto when = sent
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? (sent + _delayIntervals.minDelayBeforeMessageResend)
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: 0;
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assert(resending.data.size() >= 5);
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const auto counter = CounterFromSeq(ReadSeq(resending.data.data()));
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const auto type = uint8_t(resending.data.data()[4]);
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if (when > now) {
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RTC_LOG(LS_INFO) << logHeader()
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<< "Skip RESEND:type" << type << "#" << counter
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<< " (wait " << (when - now) << "ms).";
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break;
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} else if (enoughSpaceInPacket(buffer, resending.data.size())) {
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RTC_LOG(LS_INFO) << logHeader()
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<< "Add RESEND:type" << type << "#" << counter;
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buffer.AppendData(resending.data);
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resending.lastSent = now;
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} else {
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RTC_LOG(LS_INFO) << logHeader()
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<< "Skip RESEND:type" << type << "#" << counter
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<< " (no space, length: " << resending.data.size() << ", already: " << buffer.size() << ")";
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break;
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}
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}
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if (!_resendTimerActive) {
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_resendTimerActive = true;
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_requestSendService(
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_delayIntervals.maxDelayBeforeMessageResend,
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kServiceCauseResend);
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}
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}
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auto EncryptedConnection::encryptPrepared(const rtc::CopyOnWriteBuffer &buffer)
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-> EncryptedPacket {
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auto result = EncryptedPacket();
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result.counter = CounterFromSeq(ReadSeq(buffer.data()));
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result.bytes.resize(16 + buffer.size());
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const auto x = (_key.isOutgoing ? 0 : 8) + (_type == Type::Signaling ? 128 : 0);
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const auto key = _key.value->data();
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const auto msgKeyLarge = ConcatSHA256(
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MemorySpan{ key + 88 + x, 32 },
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MemorySpan{ buffer.data(), buffer.size() });
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const auto msgKey = result.bytes.data();
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memcpy(msgKey, msgKeyLarge.data() + 8, 16);
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auto aesKeyIv = PrepareAesKeyIv(key, msgKey, x);
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AesProcessCtr(
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MemorySpan{ buffer.data(), buffer.size() },
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result.bytes.data() + 16,
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std::move(aesKeyIv));
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return result;
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}
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bool EncryptedConnection::registerIncomingCounter(uint32_t incomingCounter) {
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auto &list = _largestIncomingCounters;
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const auto position = std::lower_bound(list.begin(), list.end(), incomingCounter);
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const auto largest = list.empty() ? 0 : list.back();
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if (position != list.end() && *position == incomingCounter) {
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// The packet is in the list already.
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return false;
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} else if (incomingCounter + kKeepIncomingCountersCount <= largest) {
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// The packet is too old.
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return false;
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}
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const auto eraseTill = std::find_if(list.begin(), list.end(), [&](uint32_t counter) {
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return (counter + kKeepIncomingCountersCount > incomingCounter);
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});
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const auto eraseCount = eraseTill - list.begin();
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const auto positionIndex = (position - list.begin()) - eraseCount;
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list.erase(list.begin(), eraseTill);
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assert(positionIndex >= 0 && positionIndex <= list.size());
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list.insert(list.begin() + positionIndex, incomingCounter);
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return true;
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}
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auto EncryptedConnection::handleIncomingPacket(const char *bytes, size_t size)
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-> absl::optional<DecryptedPacket> {
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if (size < 21 || size > kMaxIncomingPacketSize) {
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return LogError("Bad incoming packet size: ", std::to_string(size));
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}
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const auto x = (_key.isOutgoing ? 8 : 0) + (_type == Type::Signaling ? 128 : 0);
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const auto key = _key.value->data();
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const auto msgKey = reinterpret_cast<const uint8_t*>(bytes);
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const auto encryptedData = msgKey + 16;
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const auto dataSize = size - 16;
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auto aesKeyIv = PrepareAesKeyIv(key, msgKey, x);
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auto decryptionBuffer = rtc::Buffer(dataSize);
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AesProcessCtr(
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MemorySpan{ encryptedData, dataSize },
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decryptionBuffer.data(),
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std::move(aesKeyIv));
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const auto msgKeyLarge = ConcatSHA256(
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MemorySpan{ key + 88 + x, 32 },
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MemorySpan{ decryptionBuffer.data(), decryptionBuffer.size() });
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if (ConstTimeIsDifferent(msgKeyLarge.data() + 8, msgKey, 16)) {
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return LogError("Bad incoming data hash.");
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}
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const auto incomingSeq = ReadSeq(decryptionBuffer.data());
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const auto incomingCounter = CounterFromSeq(incomingSeq);
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if (!registerIncomingCounter(incomingCounter)) {
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// We've received that packet already.
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return LogError("Already handled packet received.", std::to_string(incomingCounter));
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}
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return processPacket(decryptionBuffer, incomingSeq);
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}
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absl::optional<EncryptedConnection::DecryptedRawPacket> EncryptedConnection::handleIncomingRawPacket(const char *bytes, size_t size) {
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if (size < 21 || size > kMaxIncomingPacketSize) {
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return LogError("Bad incoming packet size: ", std::to_string(size));
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}
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const auto x = (_key.isOutgoing ? 8 : 0) + (_type == Type::Signaling ? 128 : 0);
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const auto key = _key.value->data();
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const auto msgKey = reinterpret_cast<const uint8_t*>(bytes);
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const auto encryptedData = msgKey + 16;
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const auto dataSize = size - 16;
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auto aesKeyIv = PrepareAesKeyIv(key, msgKey, x);
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auto decryptionBuffer = rtc::Buffer(dataSize);
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AesProcessCtr(
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MemorySpan{ encryptedData, dataSize },
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decryptionBuffer.data(),
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std::move(aesKeyIv));
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const auto msgKeyLarge = ConcatSHA256(
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MemorySpan{ key + 88 + x, 32 },
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MemorySpan{ decryptionBuffer.data(), decryptionBuffer.size() });
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if (ConstTimeIsDifferent(msgKeyLarge.data() + 8, msgKey, 16)) {
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return LogError("Bad incoming data hash.");
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}
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const auto incomingSeq = ReadSeq(decryptionBuffer.data());
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const auto incomingCounter = CounterFromSeq(incomingSeq);
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if (!registerIncomingCounter(incomingCounter)) {
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// We've received that packet already.
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return LogError("Already handled packet received.", std::to_string(incomingCounter));
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}
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return processRawPacket(decryptionBuffer, incomingSeq);
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}
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auto EncryptedConnection::processPacket(
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|
const rtc::Buffer &fullBuffer,
|
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uint32_t packetSeq)
|
|
-> absl::optional<DecryptedPacket> {
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assert(fullBuffer.size() >= 5);
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|
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auto additionalMessage = false;
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auto firstMessageRequiringAck = true;
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auto newRequiringAckReceived = false;
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auto currentSeq = packetSeq;
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auto currentCounter = CounterFromSeq(currentSeq);
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rtc::ByteBufferReader reader(
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reinterpret_cast<const char*>(fullBuffer.data() + 4), // Skip seq.
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fullBuffer.size() - 4);
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|
|
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auto result = absl::optional<DecryptedPacket>();
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while (true) {
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const auto type = uint8_t(*reader.Data());
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const auto singleMessagePacket = ((currentSeq & kSingleMessagePacketSeqBit) != 0);
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if (singleMessagePacket && additionalMessage) {
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return LogError("Single message packet bit in not first message.");
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}
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if (type == kEmptyId) {
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if (additionalMessage) {
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return LogError("Empty message should be only the first one in the packet.");
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}
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RTC_LOG(LS_INFO) << logHeader()
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<< "Got RECV:empty" << "#" << currentCounter;
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reader.Consume(1);
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} else if (type == kAckId) {
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if (!additionalMessage) {
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return LogError("Ack message must not be the first one in the packet.");
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}
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ackMyMessage(currentSeq);
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reader.Consume(1);
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} else if (auto message = DeserializeMessage(reader, singleMessagePacket)) {
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const auto messageRequiresAck = ((currentSeq & kMessageRequiresAckSeqBit) != 0);
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const auto skipMessage = messageRequiresAck
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? !registerSentAck(currentCounter, firstMessageRequiringAck)
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: (additionalMessage && !registerIncomingCounter(currentCounter));
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if (messageRequiresAck) {
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firstMessageRequiringAck = false;
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if (!skipMessage) {
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newRequiringAckReceived = true;
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}
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sendAckPostponed(currentSeq);
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RTC_LOG(LS_INFO) << logHeader()
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<< (skipMessage ? "Repeated RECV:type" : "Got RECV:type") << type << "#" << currentCounter;
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}
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if (!skipMessage) {
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appendReceivedMessage(result, std::move(*message), currentSeq);
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}
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} else {
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return LogError("Could not parse message from packet, type: ", std::to_string(type));
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}
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if (!reader.Length()) {
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break;
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} else if (singleMessagePacket) {
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return LogError("Single message didn't fill the entire packet.");
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} else if (reader.Length() < 5) {
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return LogError("Bad remaining data size: ", std::to_string(reader.Length()));
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}
|
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const auto success = reader.ReadUInt32(¤tSeq);
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assert(success);
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(void)success;
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currentCounter = CounterFromSeq(currentSeq);
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|
|
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additionalMessage = true;
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}
|
|
|
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if (!_acksToSendSeqs.empty()) {
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if (newRequiringAckReceived) {
|
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_requestSendService(0, 0);
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} else if (!_sendAcksTimerActive) {
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_sendAcksTimerActive = true;
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_requestSendService(
|
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_delayIntervals.maxDelayBeforeAckResend,
|
|
kServiceCauseAcks);
|
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}
|
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}
|
|
|
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return result;
|
|
}
|
|
|
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auto EncryptedConnection::processRawPacket(
|
|
const rtc::Buffer &fullBuffer,
|
|
uint32_t packetSeq)
|
|
-> absl::optional<DecryptedRawPacket> {
|
|
assert(fullBuffer.size() >= 5);
|
|
|
|
auto additionalMessage = false;
|
|
auto firstMessageRequiringAck = true;
|
|
auto newRequiringAckReceived = false;
|
|
|
|
auto currentSeq = packetSeq;
|
|
auto currentCounter = CounterFromSeq(currentSeq);
|
|
rtc::ByteBufferReader reader(
|
|
reinterpret_cast<const char*>(fullBuffer.data() + 4), // Skip seq.
|
|
fullBuffer.size() - 4);
|
|
|
|
auto result = absl::optional<DecryptedRawPacket>();
|
|
while (true) {
|
|
const auto type = uint8_t(*reader.Data());
|
|
const auto singleMessagePacket = ((currentSeq & kSingleMessagePacketSeqBit) != 0);
|
|
if (singleMessagePacket && additionalMessage) {
|
|
return LogError("Single message packet bit in not first message.");
|
|
}
|
|
|
|
if (type == kEmptyId) {
|
|
if (additionalMessage) {
|
|
return LogError("Empty message should be only the first one in the packet.");
|
|
}
|
|
RTC_LOG(LS_INFO) << logHeader()
|
|
<< "Got RECV:empty" << "#" << currentCounter;
|
|
reader.Consume(1);
|
|
} else if (type == kAckId) {
|
|
if (!additionalMessage) {
|
|
return LogError("Ack message must not be the first one in the packet.");
|
|
}
|
|
ackMyMessage(currentSeq);
|
|
reader.Consume(1);
|
|
} else if (type == kCustomId) {
|
|
reader.Consume(1);
|
|
|
|
if (auto message = DeserializeRawMessage(reader, singleMessagePacket)) {
|
|
const auto messageRequiresAck = ((currentSeq & kMessageRequiresAckSeqBit) != 0);
|
|
const auto skipMessage = messageRequiresAck
|
|
? !registerSentAck(currentCounter, firstMessageRequiringAck)
|
|
: (additionalMessage && !registerIncomingCounter(currentCounter));
|
|
if (messageRequiresAck) {
|
|
firstMessageRequiringAck = false;
|
|
if (!skipMessage) {
|
|
newRequiringAckReceived = true;
|
|
}
|
|
sendAckPostponed(currentSeq);
|
|
RTC_LOG(LS_INFO) << logHeader()
|
|
<< (skipMessage ? "Repeated RECV:type" : "Got RECV:type") << type << "#" << currentCounter;
|
|
}
|
|
if (!skipMessage) {
|
|
appendReceivedRawMessage(result, std::move(*message), currentSeq);
|
|
}
|
|
} else {
|
|
return LogError("Could not parse message from packet, type: ", std::to_string(type));
|
|
}
|
|
} else {
|
|
return LogError("Could not parse message from packet, type: ", std::to_string(type));
|
|
}
|
|
if (!reader.Length()) {
|
|
break;
|
|
} else if (singleMessagePacket) {
|
|
return LogError("Single message didn't fill the entire packet.");
|
|
} else if (reader.Length() < 5) {
|
|
return LogError("Bad remaining data size: ", std::to_string(reader.Length()));
|
|
}
|
|
const auto success = reader.ReadUInt32(¤tSeq);
|
|
assert(success);
|
|
(void)success;
|
|
currentCounter = CounterFromSeq(currentSeq);
|
|
|
|
additionalMessage = true;
|
|
}
|
|
|
|
if (!_acksToSendSeqs.empty()) {
|
|
if (newRequiringAckReceived) {
|
|
_requestSendService(0, 0);
|
|
} else if (!_sendAcksTimerActive) {
|
|
_sendAcksTimerActive = true;
|
|
_requestSendService(
|
|
_delayIntervals.maxDelayBeforeAckResend,
|
|
kServiceCauseAcks);
|
|
}
|
|
}
|
|
|
|
return result;
|
|
}
|
|
|
|
void EncryptedConnection::appendReceivedMessage(
|
|
absl::optional<DecryptedPacket> &to,
|
|
Message &&message,
|
|
uint32_t incomingSeq) {
|
|
auto decrypted = DecryptedMessage{
|
|
std::move(message),
|
|
CounterFromSeq(incomingSeq)
|
|
};
|
|
if (to) {
|
|
to->additional.push_back(std::move(decrypted));
|
|
} else {
|
|
to = DecryptedPacket{ std::move(decrypted) };
|
|
}
|
|
}
|
|
|
|
void EncryptedConnection::appendReceivedRawMessage(
|
|
absl::optional<DecryptedRawPacket> &to,
|
|
rtc::CopyOnWriteBuffer &&message,
|
|
uint32_t incomingSeq) {
|
|
auto decrypted = DecryptedRawMessage{
|
|
std::move(message),
|
|
CounterFromSeq(incomingSeq)
|
|
};
|
|
if (to) {
|
|
to->additional.push_back(std::move(decrypted));
|
|
} else {
|
|
to = DecryptedRawPacket{ std::move(decrypted) };
|
|
}
|
|
}
|
|
|
|
const char *EncryptedConnection::logHeader() const {
|
|
return (_type == Type::Signaling) ? "(signaling) " : "(transport) ";
|
|
}
|
|
|
|
bool EncryptedConnection::registerSentAck(uint32_t counter, bool firstInPacket) {
|
|
auto &list = _acksSentCounters;
|
|
|
|
const auto position = std::lower_bound(list.begin(), list.end(), counter);
|
|
const auto already = (position != list.end()) && (*position == counter);
|
|
|
|
const auto was = list;
|
|
if (firstInPacket) {
|
|
list.erase(list.begin(), position);
|
|
if (!already) {
|
|
list.insert(list.begin(), counter);
|
|
}
|
|
} else if (!already) {
|
|
list.insert(position, counter);
|
|
}
|
|
return !already;
|
|
}
|
|
|
|
void EncryptedConnection::sendAckPostponed(uint32_t incomingSeq) {
|
|
auto &list = _acksToSendSeqs;
|
|
const auto already = std::find(list.begin(), list.end(), incomingSeq);
|
|
if (already == list.end()) {
|
|
list.push_back(incomingSeq);
|
|
}
|
|
}
|
|
|
|
void EncryptedConnection::ackMyMessage(uint32_t seq) {
|
|
auto type = uint8_t(0);
|
|
auto &list = _myNotYetAckedMessages;
|
|
for (auto i = list.begin(), e = list.end(); i != e; ++i) {
|
|
assert(i->data.size() >= 5);
|
|
if (ReadSeq(i->data.cdata()) == seq) {
|
|
type = uint8_t(i->data.cdata()[4]);
|
|
list.erase(i);
|
|
break;
|
|
}
|
|
}
|
|
RTC_LOG(LS_INFO) << logHeader()
|
|
<< (type ? "Got ACK:type" + std::to_string(type) + "#" : "Repeated ACK#")
|
|
<< CounterFromSeq(seq);
|
|
}
|
|
|
|
auto EncryptedConnection::DelayIntervalsByType(Type type) -> DelayIntervals {
|
|
auto result = DelayIntervals();
|
|
const auto signaling = (type == Type::Signaling);
|
|
|
|
// Don't resend faster than min delay even if we have a packet we can attach to.
|
|
result.minDelayBeforeMessageResend = signaling ? 3000 : 300;
|
|
|
|
// When max delay elapsed we resend anyway, in a dedicated packet.
|
|
result.maxDelayBeforeMessageResend = signaling ? 5000 : 1000;
|
|
result.maxDelayBeforeAckResend = signaling ? 5000 : 1000;
|
|
|
|
return result;
|
|
}
|
|
|
|
rtc::CopyOnWriteBuffer EncryptedConnection::SerializeEmptyMessageWithSeq(uint32_t seq) {
|
|
auto result = rtc::CopyOnWriteBuffer(5);
|
|
auto bytes = result.MutableData();
|
|
WriteSeq(bytes, seq);
|
|
bytes[4] = kEmptyId;
|
|
return result;
|
|
}
|
|
|
|
} // namespace tgcalls
|