From f9825168fbd61a1ec49610623d88338e47667863 Mon Sep 17 00:00:00 2001 From: Kittywhiskers Van Gogh <63189531+kwvg@users.noreply.github.com> Date: Thu, 12 Sep 2024 11:35:28 +0000 Subject: [PATCH] merge bitcoin#28196: BIP324 connection support --- src/net.cpp | 713 +++++++++++++++++- src/net.h | 267 ++++++- src/pubkey.cpp | 6 + src/pubkey.h | 3 +- src/test/bip324_tests.cpp | 10 +- src/test/fuzz/p2p_transport_serialization.cpp | 91 ++- src/test/net_tests.cpp | 526 +++++++++++++ src/test/util/net.cpp | 4 +- 8 files changed, 1559 insertions(+), 61 deletions(-) diff --git a/src/net.cpp b/src/net.cpp index d0ef500b14..89d8ee9eb9 100644 --- a/src/net.cpp +++ b/src/net.cpp @@ -959,20 +959,22 @@ bool V1Transport::SetMessageToSend(CSerializedNetMsg& msg) noexcept return true; } -Transport::BytesToSend V1Transport::GetBytesToSend() const noexcept +Transport::BytesToSend V1Transport::GetBytesToSend(bool have_next_message) const noexcept { AssertLockNotHeld(m_send_mutex); LOCK(m_send_mutex); if (m_sending_header) { return {Span{m_header_to_send}.subspan(m_bytes_sent), - // We have more to send after the header if the message has payload. - !m_message_to_send.data.empty(), + // We have more to send after the header if the message has payload, or if there + // is a next message after that. + have_next_message || !m_message_to_send.data.empty(), m_message_to_send.m_type }; } else { return {Span{m_message_to_send.data}.subspan(m_bytes_sent), - // We never have more to send after this message's payload. - false, + // We only have more to send after this message's payload if there is another + // message. + have_next_message, m_message_to_send.m_type }; } @@ -1003,16 +1005,676 @@ size_t V1Transport::GetSendMemoryUsage() const noexcept return m_message_to_send.GetMemoryUsage(); } +namespace { + +/** List of short messages as defined in BIP324, in order. + * + * Only message types that are actually implemented in this codebase need to be listed, as other + * messages get ignored anyway - whether we know how to decode them or not. + */ +const std::array V2_MESSAGE_IDS = { + "", // 12 bytes follow encoding the message type like in V1 + NetMsgType::ADDR, + NetMsgType::BLOCK, + NetMsgType::BLOCKTXN, + NetMsgType::CMPCTBLOCK, + "", /* FEEFILTER is not implemented in Dash */ + NetMsgType::FILTERADD, + NetMsgType::FILTERCLEAR, + NetMsgType::FILTERLOAD, + NetMsgType::GETBLOCKS, + NetMsgType::GETBLOCKTXN, + NetMsgType::GETDATA, + NetMsgType::GETHEADERS, + NetMsgType::HEADERS, + NetMsgType::INV, + NetMsgType::MEMPOOL, + NetMsgType::MERKLEBLOCK, + NetMsgType::NOTFOUND, + NetMsgType::PING, + NetMsgType::PONG, + NetMsgType::SENDCMPCT, + NetMsgType::TX, + NetMsgType::GETCFILTERS, + NetMsgType::CFILTER, + NetMsgType::GETCFHEADERS, + NetMsgType::CFHEADERS, + NetMsgType::GETCFCHECKPT, + NetMsgType::CFCHECKPT, + NetMsgType::ADDRV2, + // Unimplemented message types that are assigned in BIP324: + "", + "", + "", + "" +}; + +class V2MessageMap +{ + std::unordered_map m_map; + +public: + V2MessageMap() noexcept + { + for (size_t i = 1; i < std::size(V2_MESSAGE_IDS); ++i) { + m_map.emplace(V2_MESSAGE_IDS[i], i); + } + } + + std::optional operator()(const std::string& message_name) const noexcept + { + auto it = m_map.find(message_name); + if (it == m_map.end()) return std::nullopt; + return it->second; + } +}; + +const V2MessageMap V2_MESSAGE_MAP; + +} // namespace + +V2Transport::V2Transport(NodeId nodeid, bool initiating, int type_in, int version_in) noexcept : + m_cipher{}, m_initiating{initiating}, m_nodeid{nodeid}, + m_v1_fallback{nodeid, type_in, version_in}, m_recv_type{type_in}, m_recv_version{version_in}, + m_recv_state{initiating ? RecvState::KEY : RecvState::KEY_MAYBE_V1}, + m_send_state{initiating ? SendState::AWAITING_KEY : SendState::MAYBE_V1} +{ + // Construct garbage (including its length) using a FastRandomContext. + FastRandomContext rng; + size_t garbage_len = rng.randrange(MAX_GARBAGE_LEN + 1); + // Initialize the send buffer with ellswift pubkey + garbage. + m_send_buffer.resize(EllSwiftPubKey::size() + garbage_len); + std::copy(std::begin(m_cipher.GetOurPubKey()), std::end(m_cipher.GetOurPubKey()), MakeWritableByteSpan(m_send_buffer).begin()); + rng.fillrand(MakeWritableByteSpan(m_send_buffer).subspan(EllSwiftPubKey::size())); +} + +V2Transport::V2Transport(NodeId nodeid, bool initiating, int type_in, int version_in, const CKey& key, Span ent32, Span garbage) noexcept : + m_cipher{key, ent32}, m_initiating{initiating}, m_nodeid{nodeid}, + m_v1_fallback{nodeid, type_in, version_in}, m_recv_type{type_in}, m_recv_version{version_in}, + m_recv_state{initiating ? RecvState::KEY : RecvState::KEY_MAYBE_V1}, + m_send_state{initiating ? SendState::AWAITING_KEY : SendState::MAYBE_V1} +{ + assert(garbage.size() <= MAX_GARBAGE_LEN); + // Initialize the send buffer with ellswift pubkey + provided garbage. + m_send_buffer.resize(EllSwiftPubKey::size() + garbage.size()); + std::copy(std::begin(m_cipher.GetOurPubKey()), std::end(m_cipher.GetOurPubKey()), MakeWritableByteSpan(m_send_buffer).begin()); + std::copy(garbage.begin(), garbage.end(), m_send_buffer.begin() + EllSwiftPubKey::size()); +} + +void V2Transport::SetReceiveState(RecvState recv_state) noexcept +{ + AssertLockHeld(m_recv_mutex); + // Enforce allowed state transitions. + switch (m_recv_state) { + case RecvState::KEY_MAYBE_V1: + Assume(recv_state == RecvState::KEY || recv_state == RecvState::V1); + break; + case RecvState::KEY: + Assume(recv_state == RecvState::GARB_GARBTERM); + break; + case RecvState::GARB_GARBTERM: + Assume(recv_state == RecvState::GARBAUTH); + break; + case RecvState::GARBAUTH: + Assume(recv_state == RecvState::VERSION); + break; + case RecvState::VERSION: + Assume(recv_state == RecvState::APP); + break; + case RecvState::APP: + Assume(recv_state == RecvState::APP_READY); + break; + case RecvState::APP_READY: + Assume(recv_state == RecvState::APP); + break; + case RecvState::V1: + Assume(false); // V1 state cannot be left + break; + } + // Change state. + m_recv_state = recv_state; +} + +void V2Transport::SetSendState(SendState send_state) noexcept +{ + AssertLockHeld(m_send_mutex); + // Enforce allowed state transitions. + switch (m_send_state) { + case SendState::MAYBE_V1: + Assume(send_state == SendState::V1 || send_state == SendState::AWAITING_KEY); + break; + case SendState::AWAITING_KEY: + Assume(send_state == SendState::READY); + break; + case SendState::READY: + case SendState::V1: + Assume(false); // Final states + break; + } + // Change state. + m_send_state = send_state; +} + +bool V2Transport::ReceivedMessageComplete() const noexcept +{ + AssertLockNotHeld(m_recv_mutex); + LOCK(m_recv_mutex); + if (m_recv_state == RecvState::V1) return m_v1_fallback.ReceivedMessageComplete(); + + return m_recv_state == RecvState::APP_READY; +} + +void V2Transport::ProcessReceivedMaybeV1Bytes() noexcept +{ + AssertLockHeld(m_recv_mutex); + AssertLockNotHeld(m_send_mutex); + Assume(m_recv_state == RecvState::KEY_MAYBE_V1); + // We still have to determine if this is a v1 or v2 connection. The bytes being received could + // be the beginning of either a v1 packet (network magic + "version\x00"), or of a v2 public + // key. BIP324 specifies that a mismatch with this 12-byte string should trigger sending of the + // key. + std::array v1_prefix = {0, 0, 0, 0, 'v', 'e', 'r', 's', 'i', 'o', 'n', 0}; + std::copy(std::begin(Params().MessageStart()), std::end(Params().MessageStart()), v1_prefix.begin()); + Assume(m_recv_buffer.size() <= v1_prefix.size()); + if (!std::equal(m_recv_buffer.begin(), m_recv_buffer.end(), v1_prefix.begin())) { + // Mismatch with v1 prefix, so we can assume a v2 connection. + SetReceiveState(RecvState::KEY); // Convert to KEY state, leaving received bytes around. + // Transition the sender to AWAITING_KEY state (if not already). + LOCK(m_send_mutex); + SetSendState(SendState::AWAITING_KEY); + } else if (m_recv_buffer.size() == v1_prefix.size()) { + // Full match with the v1 prefix, so fall back to v1 behavior. + LOCK(m_send_mutex); + Span feedback{m_recv_buffer}; + // Feed already received bytes to v1 transport. It should always accept these, because it's + // less than the size of a v1 header, and these are the first bytes fed to m_v1_fallback. + bool ret = m_v1_fallback.ReceivedBytes(feedback); + Assume(feedback.empty()); + Assume(ret); + SetReceiveState(RecvState::V1); + SetSendState(SendState::V1); + // Reset v2 transport buffers to save memory. + m_recv_buffer = {}; + m_send_buffer = {}; + } else { + // We have not received enough to distinguish v1 from v2 yet. Wait until more bytes come. + } +} + +bool V2Transport::ProcessReceivedKeyBytes() noexcept +{ + AssertLockHeld(m_recv_mutex); + AssertLockNotHeld(m_send_mutex); + Assume(m_recv_state == RecvState::KEY); + Assume(m_recv_buffer.size() <= EllSwiftPubKey::size()); + + // As a special exception, if bytes 4-16 of the key on a responder connection match the + // corresponding bytes of a V1 version message, but bytes 0-4 don't match the network magic + // (if they did, we'd have switched to V1 state already), assume this is a peer from + // another network, and disconnect them. They will almost certainly disconnect us too when + // they receive our uniformly random key and garbage, but detecting this case specially + // means we can log it. + static constexpr std::array MATCH = {'v', 'e', 'r', 's', 'i', 'o', 'n', 0, 0, 0, 0, 0}; + static constexpr size_t OFFSET = sizeof(CMessageHeader::MessageStartChars); + if (!m_initiating && m_recv_buffer.size() >= OFFSET + MATCH.size()) { + if (std::equal(MATCH.begin(), MATCH.end(), m_recv_buffer.begin() + OFFSET)) { + LogPrint(BCLog::NET, "V2 transport error: V1 peer with wrong MessageStart %s\n", + HexStr(Span(m_recv_buffer).first(OFFSET))); + return false; + } + } + + if (m_recv_buffer.size() == EllSwiftPubKey::size()) { + // Other side's key has been fully received, and can now be Diffie-Hellman combined with + // our key to initialize the encryption ciphers. + + // Initialize the ciphers. + EllSwiftPubKey ellswift(MakeByteSpan(m_recv_buffer)); + LOCK(m_send_mutex); + m_cipher.Initialize(ellswift, m_initiating); + + // Switch receiver state to GARB_GARBTERM. + SetReceiveState(RecvState::GARB_GARBTERM); + m_recv_buffer.clear(); + + // Switch sender state to READY. + SetSendState(SendState::READY); + + // Append the garbage terminator to the send buffer. + size_t garbage_len = m_send_buffer.size() - EllSwiftPubKey::size(); + m_send_buffer.resize(m_send_buffer.size() + BIP324Cipher::GARBAGE_TERMINATOR_LEN); + std::copy(m_cipher.GetSendGarbageTerminator().begin(), + m_cipher.GetSendGarbageTerminator().end(), + MakeWritableByteSpan(m_send_buffer).last(BIP324Cipher::GARBAGE_TERMINATOR_LEN).begin()); + + // Construct garbage authentication packet in the send buffer (using the garbage data which + // is still there). + m_send_buffer.resize(m_send_buffer.size() + BIP324Cipher::EXPANSION); + m_cipher.Encrypt( + /*contents=*/{}, + /*aad=*/MakeByteSpan(m_send_buffer).subspan(EllSwiftPubKey::size(), garbage_len), + /*ignore=*/false, + /*output=*/MakeWritableByteSpan(m_send_buffer).last(BIP324Cipher::EXPANSION)); + + // Construct version packet in the send buffer. + m_send_buffer.resize(m_send_buffer.size() + BIP324Cipher::EXPANSION + VERSION_CONTENTS.size()); + m_cipher.Encrypt( + /*contents=*/VERSION_CONTENTS, + /*aad=*/{}, + /*ignore=*/false, + /*output=*/MakeWritableByteSpan(m_send_buffer).last(BIP324Cipher::EXPANSION + VERSION_CONTENTS.size())); + } else { + // We still have to receive more key bytes. + } + return true; +} + +bool V2Transport::ProcessReceivedGarbageBytes() noexcept +{ + AssertLockHeld(m_recv_mutex); + Assume(m_recv_state == RecvState::GARB_GARBTERM); + Assume(m_recv_buffer.size() <= MAX_GARBAGE_LEN + BIP324Cipher::GARBAGE_TERMINATOR_LEN); + if (m_recv_buffer.size() >= BIP324Cipher::GARBAGE_TERMINATOR_LEN) { + if (MakeByteSpan(m_recv_buffer).last(BIP324Cipher::GARBAGE_TERMINATOR_LEN) == m_cipher.GetReceiveGarbageTerminator()) { + // Garbage terminator received. Switch to receiving garbage authentication packet. + m_recv_garbage = std::move(m_recv_buffer); + m_recv_garbage.resize(m_recv_garbage.size() - BIP324Cipher::GARBAGE_TERMINATOR_LEN); + m_recv_buffer.clear(); + SetReceiveState(RecvState::GARBAUTH); + } else if (m_recv_buffer.size() == MAX_GARBAGE_LEN + BIP324Cipher::GARBAGE_TERMINATOR_LEN) { + // We've reached the maximum length for garbage + garbage terminator, and the + // terminator still does not match. Abort. + LogPrint(BCLog::NET, "V2 transport error: missing garbage terminator, peer=%d\n", m_nodeid); + return false; + } else { + // We still need to receive more garbage and/or garbage terminator bytes. + } + } else { + // We have less than GARBAGE_TERMINATOR_LEN (16) bytes, so we certainly need to receive + // more first. + } + return true; +} + +bool V2Transport::ProcessReceivedPacketBytes() noexcept +{ + AssertLockHeld(m_recv_mutex); + Assume(m_recv_state == RecvState::GARBAUTH || m_recv_state == RecvState::VERSION || + m_recv_state == RecvState::APP); + + // The maximum permitted contents length for a packet, consisting of: + // - 0x00 byte: indicating long message type encoding + // - 12 bytes of message type + // - payload + static constexpr size_t MAX_CONTENTS_LEN = + 1 + CMessageHeader::COMMAND_SIZE + + std::min(MAX_SIZE, MAX_PROTOCOL_MESSAGE_LENGTH); + + if (m_recv_buffer.size() == BIP324Cipher::LENGTH_LEN) { + // Length descriptor received. + m_recv_len = m_cipher.DecryptLength(MakeByteSpan(m_recv_buffer)); + if (m_recv_len > MAX_CONTENTS_LEN) { + LogPrint(BCLog::NET, "V2 transport error: packet too large (%u bytes), peer=%d\n", m_recv_len, m_nodeid); + return false; + } + } else if (m_recv_buffer.size() > BIP324Cipher::LENGTH_LEN && m_recv_buffer.size() == m_recv_len + BIP324Cipher::EXPANSION) { + // Ciphertext received, decrypt it into m_recv_decode_buffer. + // Note that it is impossible to reach this branch without hitting the branch above first, + // as GetMaxBytesToProcess only allows up to LENGTH_LEN into the buffer before that point. + m_recv_decode_buffer.resize(m_recv_len); + bool ignore{false}; + Span aad; + if (m_recv_state == RecvState::GARBAUTH) aad = MakeByteSpan(m_recv_garbage); + bool ret = m_cipher.Decrypt( + /*input=*/MakeByteSpan(m_recv_buffer).subspan(BIP324Cipher::LENGTH_LEN), + /*aad=*/aad, + /*ignore=*/ignore, + /*contents=*/MakeWritableByteSpan(m_recv_decode_buffer)); + if (!ret) { + LogPrint(BCLog::NET, "V2 transport error: packet decryption failure (%u bytes), peer=%d\n", m_recv_len, m_nodeid); + return false; + } + // Feed the last 4 bytes of the Poly1305 authentication tag (and its timing) into our RNG. + RandAddEvent(ReadLE32(m_recv_buffer.data() + m_recv_buffer.size() - 4)); + + // At this point we have a valid packet decrypted into m_recv_decode_buffer. Depending on + // the current state, decide what to do with it. + switch (m_recv_state) { + case RecvState::GARBAUTH: + // Ignore flag does not matter for garbage authentication. Any valid packet functions + // as authentication. Receive and process the version packet next. + SetReceiveState(RecvState::VERSION); + m_recv_garbage = {}; + break; + case RecvState::VERSION: + if (!ignore) { + // Version message received; transition to application phase. The contents is + // ignored, but can be used for future extensions. + SetReceiveState(RecvState::APP); + } + break; + case RecvState::APP: + if (!ignore) { + // Application message decrypted correctly. It can be extracted using GetMessage(). + SetReceiveState(RecvState::APP_READY); + } + break; + default: + // Any other state is invalid (this function should not have been called). + Assume(false); + } + // Wipe the receive buffer where the next packet will be received into. + m_recv_buffer = {}; + // In all but APP_READY state, we can wipe the decoded contents. + if (m_recv_state != RecvState::APP_READY) m_recv_decode_buffer = {}; + } else { + // We either have less than 3 bytes, so we don't know the packet's length yet, or more + // than 3 bytes but less than the packet's full ciphertext. Wait until those arrive. + } + return true; +} + +size_t V2Transport::GetMaxBytesToProcess() noexcept +{ + AssertLockHeld(m_recv_mutex); + switch (m_recv_state) { + case RecvState::KEY_MAYBE_V1: + // During the KEY_MAYBE_V1 state we do not allow more than the length of v1 prefix into the + // receive buffer. + Assume(m_recv_buffer.size() <= V1_PREFIX_LEN); + // As long as we're not sure if this is a v1 or v2 connection, don't receive more than what + // is strictly necessary to distinguish the two (12 bytes). If we permitted more than + // the v1 header size (24 bytes), we may not be able to feed the already-received bytes + // back into the m_v1_fallback V1 transport. + return V1_PREFIX_LEN - m_recv_buffer.size(); + case RecvState::KEY: + // During the KEY state, we only allow the 64-byte key into the receive buffer. + Assume(m_recv_buffer.size() <= EllSwiftPubKey::size()); + // As long as we have not received the other side's public key, don't receive more than + // that (64 bytes), as garbage follows, and locating the garbage terminator requires the + // key exchange first. + return EllSwiftPubKey::size() - m_recv_buffer.size(); + case RecvState::GARB_GARBTERM: + // Process garbage bytes one by one (because terminator may appear anywhere). + return 1; + case RecvState::GARBAUTH: + case RecvState::VERSION: + case RecvState::APP: + // These three states all involve decoding a packet. Process the length descriptor first, + // so that we know where the current packet ends (and we don't process bytes from the next + // packet or decoy yet). Then, process the ciphertext bytes of the current packet. + if (m_recv_buffer.size() < BIP324Cipher::LENGTH_LEN) { + return BIP324Cipher::LENGTH_LEN - m_recv_buffer.size(); + } else { + // Note that BIP324Cipher::EXPANSION is the total difference between contents size + // and encoded packet size, which includes the 3 bytes due to the packet length. + // When transitioning from receiving the packet length to receiving its ciphertext, + // the encrypted packet length is left in the receive buffer. + return BIP324Cipher::EXPANSION + m_recv_len - m_recv_buffer.size(); + } + case RecvState::APP_READY: + // No bytes can be processed until GetMessage() is called. + return 0; + case RecvState::V1: + // Not allowed (must be dealt with by the caller). + Assume(false); + return 0; + } + Assume(false); // unreachable + return 0; +} + +bool V2Transport::ReceivedBytes(Span& msg_bytes) noexcept +{ + AssertLockNotHeld(m_recv_mutex); + /** How many bytes to allocate in the receive buffer at most above what is received so far. */ + static constexpr size_t MAX_RESERVE_AHEAD = 256 * 1024; + + LOCK(m_recv_mutex); + if (m_recv_state == RecvState::V1) return m_v1_fallback.ReceivedBytes(msg_bytes); + + // Process the provided bytes in msg_bytes in a loop. In each iteration a nonzero number of + // bytes (decided by GetMaxBytesToProcess) are taken from the beginning om msg_bytes, and + // appended to m_recv_buffer. Then, depending on the receiver state, one of the + // ProcessReceived*Bytes functions is called to process the bytes in that buffer. + while (!msg_bytes.empty()) { + // Decide how many bytes to copy from msg_bytes to m_recv_buffer. + size_t max_read = GetMaxBytesToProcess(); + + // Reserve space in the buffer if there is not enough. + if (m_recv_buffer.size() + std::min(msg_bytes.size(), max_read) > m_recv_buffer.capacity()) { + switch (m_recv_state) { + case RecvState::KEY_MAYBE_V1: + case RecvState::KEY: + case RecvState::GARB_GARBTERM: + // During the initial states (key/garbage), allocate once to fit the maximum (4111 + // bytes). + m_recv_buffer.reserve(MAX_GARBAGE_LEN + BIP324Cipher::GARBAGE_TERMINATOR_LEN); + break; + case RecvState::GARBAUTH: + case RecvState::VERSION: + case RecvState::APP: { + // During states where a packet is being received, as much as is expected but never + // more than MAX_RESERVE_AHEAD bytes in addition to what is received so far. + // This means attackers that want to cause us to waste allocated memory are limited + // to MAX_RESERVE_AHEAD above the largest allowed message contents size, and to + // MAX_RESERVE_AHEAD more than they've actually sent us. + size_t alloc_add = std::min(max_read, msg_bytes.size() + MAX_RESERVE_AHEAD); + m_recv_buffer.reserve(m_recv_buffer.size() + alloc_add); + break; + } + case RecvState::APP_READY: + // The buffer is empty in this state. + Assume(m_recv_buffer.empty()); + break; + case RecvState::V1: + // Should have bailed out above. + Assume(false); + break; + } + } + + // Can't read more than provided input. + max_read = std::min(msg_bytes.size(), max_read); + // Copy data to buffer. + m_recv_buffer.insert(m_recv_buffer.end(), UCharCast(msg_bytes.data()), UCharCast(msg_bytes.data() + max_read)); + msg_bytes = msg_bytes.subspan(max_read); + + // Process data in the buffer. + switch (m_recv_state) { + case RecvState::KEY_MAYBE_V1: + ProcessReceivedMaybeV1Bytes(); + if (m_recv_state == RecvState::V1) return true; + break; + + case RecvState::KEY: + if (!ProcessReceivedKeyBytes()) return false; + break; + + case RecvState::GARB_GARBTERM: + if (!ProcessReceivedGarbageBytes()) return false; + break; + + case RecvState::GARBAUTH: + case RecvState::VERSION: + case RecvState::APP: + if (!ProcessReceivedPacketBytes()) return false; + break; + + case RecvState::APP_READY: + return true; + + case RecvState::V1: + // We should have bailed out before. + Assume(false); + break; + } + // Make sure we have made progress before continuing. + Assume(max_read > 0); + } + + return true; +} + +std::optional V2Transport::GetMessageType(Span& contents) noexcept +{ + if (contents.size() == 0) return std::nullopt; // Empty contents + uint8_t first_byte = contents[0]; + contents = contents.subspan(1); // Strip first byte. + + if (first_byte != 0) { + // Short (1 byte) encoding. + if (first_byte < std::size(V2_MESSAGE_IDS)) { + // Valid short message id. + return V2_MESSAGE_IDS[first_byte]; + } else { + // Unknown short message id. + return std::nullopt; + } + } + + if (contents.size() < CMessageHeader::COMMAND_SIZE) { + return std::nullopt; // Long encoding needs 12 message type bytes. + } + + size_t msg_type_len{0}; + while (msg_type_len < CMessageHeader::COMMAND_SIZE && contents[msg_type_len] != 0) { + // Verify that message type bytes before the first 0x00 are in range. + if (contents[msg_type_len] < ' ' || contents[msg_type_len] > 0x7F) { + return {}; + } + ++msg_type_len; + } + std::string ret{reinterpret_cast(contents.data()), msg_type_len}; + while (msg_type_len < CMessageHeader::COMMAND_SIZE) { + // Verify that message type bytes after the first 0x00 are also 0x00. + if (contents[msg_type_len] != 0) return {}; + ++msg_type_len; + } + // Strip message type bytes of contents. + contents = contents.subspan(CMessageHeader::COMMAND_SIZE); + return {std::move(ret)}; +} + +CNetMessage V2Transport::GetReceivedMessage(std::chrono::microseconds time, bool& reject_message) noexcept +{ + AssertLockNotHeld(m_recv_mutex); + LOCK(m_recv_mutex); + if (m_recv_state == RecvState::V1) return m_v1_fallback.GetReceivedMessage(time, reject_message); + + Assume(m_recv_state == RecvState::APP_READY); + Span contents{m_recv_decode_buffer}; + auto msg_type = GetMessageType(contents); + CDataStream ret(m_recv_type, m_recv_version); + CNetMessage msg{std::move(ret)}; + // Note that BIP324Cipher::EXPANSION also includes the length descriptor size. + msg.m_raw_message_size = m_recv_decode_buffer.size() + BIP324Cipher::EXPANSION; + if (msg_type) { + reject_message = false; + msg.m_type = std::move(*msg_type); + msg.m_time = time; + msg.m_message_size = contents.size(); + msg.m_recv.resize(contents.size()); + std::copy(contents.begin(), contents.end(), UCharCast(msg.m_recv.data())); + } else { + LogPrint(BCLog::NET, "V2 transport error: invalid message type (%u bytes contents), peer=%d\n", m_recv_decode_buffer.size(), m_nodeid); + reject_message = true; + } + m_recv_decode_buffer = {}; + SetReceiveState(RecvState::APP); + + return msg; +} + +bool V2Transport::SetMessageToSend(CSerializedNetMsg& msg) noexcept +{ + AssertLockNotHeld(m_send_mutex); + LOCK(m_send_mutex); + if (m_send_state == SendState::V1) return m_v1_fallback.SetMessageToSend(msg); + // We only allow adding a new message to be sent when in the READY state (so the packet cipher + // is available) and the send buffer is empty. This limits the number of messages in the send + // buffer to just one, and leaves the responsibility for queueing them up to the caller. + if (!(m_send_state == SendState::READY && m_send_buffer.empty())) return false; + // Construct contents (encoding message type + payload). + std::vector contents; + auto short_message_id = V2_MESSAGE_MAP(msg.m_type); + if (short_message_id) { + contents.resize(1 + msg.data.size()); + contents[0] = *short_message_id; + std::copy(msg.data.begin(), msg.data.end(), contents.begin() + 1); + } else { + // Initialize with zeroes, and then write the message type string starting at offset 1. + // This means contents[0] and the unused positions in contents[1..13] remain 0x00. + contents.resize(1 + CMessageHeader::COMMAND_SIZE + msg.data.size(), 0); + std::copy(msg.m_type.begin(), msg.m_type.end(), contents.data() + 1); + std::copy(msg.data.begin(), msg.data.end(), contents.begin() + 1 + CMessageHeader::COMMAND_SIZE); + } + // Construct ciphertext in send buffer. + m_send_buffer.resize(contents.size() + BIP324Cipher::EXPANSION); + m_cipher.Encrypt(MakeByteSpan(contents), {}, false, MakeWritableByteSpan(m_send_buffer)); + m_send_type = msg.m_type; + // Release memory + msg.data = {}; + return true; +} + +Transport::BytesToSend V2Transport::GetBytesToSend(bool have_next_message) const noexcept +{ + AssertLockNotHeld(m_send_mutex); + LOCK(m_send_mutex); + if (m_send_state == SendState::V1) return m_v1_fallback.GetBytesToSend(have_next_message); + + // We do not send anything in MAYBE_V1 state (as we don't know if the peer is v1 or v2), + // despite there being data in the send buffer in that state. + if (m_send_state == SendState::MAYBE_V1) return {{}, false, m_send_type}; + Assume(m_send_pos <= m_send_buffer.size()); + return { + Span{m_send_buffer}.subspan(m_send_pos), + // We only have more to send after the current m_send_buffer if there is a (next) + // message to be sent, and we're capable of sending packets. */ + have_next_message && m_send_state == SendState::READY, + m_send_type + }; +} + +void V2Transport::MarkBytesSent(size_t bytes_sent) noexcept +{ + AssertLockNotHeld(m_send_mutex); + LOCK(m_send_mutex); + if (m_send_state == SendState::V1) return m_v1_fallback.MarkBytesSent(bytes_sent); + + m_send_pos += bytes_sent; + Assume(m_send_pos <= m_send_buffer.size()); + // Only wipe the buffer when everything is sent in the READY state. In the AWAITING_KEY state + // we still need the garbage that's in the send buffer to construct the garbage authentication + // packet. + if (m_send_state == SendState::READY && m_send_pos == m_send_buffer.size()) { + m_send_pos = 0; + m_send_buffer = {}; + } +} + +size_t V2Transport::GetSendMemoryUsage() const noexcept +{ + AssertLockNotHeld(m_send_mutex); + LOCK(m_send_mutex); + if (m_send_state == SendState::V1) return m_v1_fallback.GetSendMemoryUsage(); + + return sizeof(m_send_buffer) + memusage::DynamicUsage(m_send_buffer); +} + std::pair CConnman::SocketSendData(CNode& node) const { auto it = node.vSendMsg.begin(); size_t nSentSize = 0; bool data_left{false}; //!< second return value (whether unsent data remains) + std::optional expected_more; while (true) { if (it != node.vSendMsg.end()) { // If possible, move one message from the send queue to the transport. This fails when - // there is an existing message still being sent. + // there is an existing message still being sent, or (for v2 transports) when the + // handshake has not yet completed. size_t memusage = it->GetMemoryUsage(); if (node.m_transport->SetMessageToSend(*it)) { // Update memory usage of send buffer (as *it will be deleted). @@ -1020,7 +1682,12 @@ std::pair CConnman::SocketSendData(CNode& node) const ++it; } } - const auto& [data, more, msg_type] = node.m_transport->GetBytesToSend(); + const auto& [data, more, msg_type] = node.m_transport->GetBytesToSend(it != node.vSendMsg.end()); + // We rely on the 'more' value returned by GetBytesToSend to correctly predict whether more + // bytes are still to be sent, to correctly set the MSG_MORE flag. As a sanity check, + // verify that the previously returned 'more' was correct. + if (expected_more.has_value()) Assume(!data.empty() == *expected_more); + expected_more = more; data_left = !data.empty(); // will be overwritten on next loop if all of data gets sent int nBytes = 0; if (!data.empty()) { @@ -1033,9 +1700,7 @@ std::pair CConnman::SocketSendData(CNode& node) const } int flags = MSG_NOSIGNAL | MSG_DONTWAIT; #ifdef MSG_MORE - // We have more to send if either the transport itself has more, or if we have more - // messages to send. - if (more || it != node.vSendMsg.end()) { + if (more) { flags |= MSG_MORE; } #endif @@ -1404,8 +2069,8 @@ void CConnman::DisconnectNodes() } if (GetTimeMillis() < pnode->nDisconnectLingerTime) { // everything flushed to the kernel? - const auto& [to_send, _more, _msg_type] = pnode->m_transport->GetBytesToSend(); - const bool queue_is_empty{to_send.empty() && pnode->nSendMsgSize == 0}; + const auto& [to_send, more, _msg_type] = pnode->m_transport->GetBytesToSend(pnode->nSendMsgSize != 0); + const bool queue_is_empty{to_send.empty() && !more}; if (!pnode->fSocketShutdown && queue_is_empty) { LOCK(pnode->m_sock_mutex); if (pnode->m_sock) { @@ -1963,8 +2628,8 @@ void CConnman::SocketHandlerConnected(const std::set& recv_set, // receiving data. This means properly utilizing TCP flow control signalling. // * Otherwise, if there is space left in the receive buffer (!fPauseRecv), try // receiving data (which should succeed as the socket signalled as receivable). - const auto& [to_send, _more, _msg_type] = it->second->m_transport->GetBytesToSend(); - const bool queue_is_empty{to_send.empty() && it->second->nSendMsgSize == 0}; + const auto& [to_send, more, _msg_type] = it->second->m_transport->GetBytesToSend(it->second->nSendMsgSize != 0); + const bool queue_is_empty{to_send.empty() && !more}; if (!it->second->fPauseRecv && !it->second->fDisconnect && queue_is_empty) { it->second->AddRef(); vReceivableNodes.emplace(it->second); @@ -1979,8 +2644,8 @@ void CConnman::SocketHandlerConnected(const std::set& recv_set, // but don't have any in this iteration LOCK(cs_mapNodesWithDataToSend); for (auto it = mapNodesWithDataToSend.begin(); it != mapNodesWithDataToSend.end(); ) { - const auto& [to_send, _more, _msg_type] = it->second->m_transport->GetBytesToSend(); - if (to_send.empty() && it->second->nSendMsgSize == 0) { + const auto& [to_send, more, _msg_type] = it->second->m_transport->GetBytesToSend(it->second->nSendMsgSize != 0); + if (to_send.empty() && !more) { // See comment in PushMessage it->second->Release(); it = mapNodesWithDataToSend.erase(it); @@ -4146,7 +4811,10 @@ void CConnman::PushMessage(CNode* pnode, CSerializedNetMsg&& msg) { LOCK(pnode->cs_vSend); - const auto& [to_send, _more, _msg_type] = pnode->m_transport->GetBytesToSend(); + // Check if the transport still has unsent bytes, and indicate to it that we're about to + // give it a message to send. + const auto& [to_send, more, _msg_type] = + pnode->m_transport->GetBytesToSend(/*have_next_message=*/true); const bool queue_was_empty{to_send.empty() && pnode->vSendMsg.empty()}; // Update memory usage of send buffer. @@ -4167,9 +4835,14 @@ void CConnman::PushMessage(CNode* pnode, CSerializedNetMsg&& msg) } } - // Wake up select() call in case there was no pending data before (so it was not selecting - // this socket for sending) - if (queue_was_empty) { + // If there was nothing to send before, and there is now (predicted by the "more" value + // returned by the GetBytesToSend call above), attempt "optimistic write": + // because the poll/select loop may pause for SELECT_TIMEOUT_MILLISECONDS before actually + // doing a send, try sending from the calling thread if the queue was empty before. + // With a V1Transport, more will always be true here, because adding a message always + // results in sendable bytes there, but with V2Transport this is not the case (it may + // still be in the handshake). + if (queue_was_empty && more) { if (m_wakeup_pipe && m_wakeup_pipe->m_need_wakeup.load()) { m_wakeup_pipe->Write(); } diff --git a/src/net.h b/src/net.h index 732bf328e5..8a97076052 100644 --- a/src/net.h +++ b/src/net.h @@ -7,6 +7,7 @@ #define BITCOIN_NET_H #include +#include #include #include #include @@ -302,8 +303,6 @@ public: /** Returns true if the current message is complete (so GetReceivedMessage can be called). */ virtual bool ReceivedMessageComplete() const = 0; - /** Set the deserialization context version for objects returned by GetReceivedMessage. */ - virtual void SetReceiveVersion(int version) = 0; /** Feed wire bytes to the transport. * @@ -336,7 +335,8 @@ public: * - Span to_send: span of bytes to be sent over the wire (possibly empty). * - bool more: whether there will be more bytes to be sent after the ones in to_send are * all sent (as signaled by MarkBytesSent()). - * - const std::string& m_type: message type on behalf of which this is being sent. + * - const std::string& m_type: message type on behalf of which this is being sent + * ("" for bytes that are not on behalf of any message). */ using BytesToSend = std::tuple< Span /*to_send*/, @@ -344,19 +344,42 @@ public: const std::string& /*m_type*/ >; - /** Get bytes to send on the wire. + /** Get bytes to send on the wire, if any, along with other information about it. * * As a const function, it does not modify the transport's observable state, and is thus safe * to be called multiple times. * - * The bytes returned by this function act as a stream which can only be appended to. This - * means that with the exception of MarkBytesSent, operations on the transport can only append - * to what is being returned. + * @param[in] have_next_message If true, the "more" return value reports whether more will + * be sendable after a SetMessageToSend call. It is set by the caller when they know + * they have another message ready to send, and only care about what happens + * after that. The have_next_message argument only affects this "more" return value + * and nothing else. * - * Note that m_type and to_send refer to data that is internal to the transport, and calling - * any non-const function on this object may invalidate them. + * Effectively, there are three possible outcomes about whether there are more bytes + * to send: + * - Yes: the transport itself has more bytes to send later. For example, for + * V1Transport this happens during the sending of the header of a + * message, when there is a non-empty payload that follows. + * - No: the transport itself has no more bytes to send, but will have bytes to + * send if handed a message through SetMessageToSend. In V1Transport this + * happens when sending the payload of a message. + * - Blocked: the transport itself has no more bytes to send, and is also incapable + * of sending anything more at all now, if it were handed another + * message to send. This occurs in V2Transport before the handshake is + * complete, as the encryption ciphers are not set up for sending + * messages before that point. + * + * The boolean 'more' is true for Yes, false for Blocked, and have_next_message + * controls what is returned for No. + * + * @return a BytesToSend object. The to_send member returned acts as a stream which is only + * ever appended to. This means that with the exception of MarkBytesSent (which pops + * bytes off the front of later to_sends), operations on the transport can only append + * to what is being returned. Also note that m_type and to_send refer to data that is + * internal to the transport, and calling any non-const function on this object may + * invalidate them. */ - virtual BytesToSend GetBytesToSend() const noexcept = 0; + virtual BytesToSend GetBytesToSend(bool have_next_message) const noexcept = 0; /** Report how many bytes returned by the last GetBytesToSend() have been sent. * @@ -428,14 +451,6 @@ public: return WITH_LOCK(m_recv_mutex, return CompleteInternal()); } - void SetReceiveVersion(int nVersionIn) override EXCLUSIVE_LOCKS_REQUIRED(!m_recv_mutex) - { - AssertLockNotHeld(m_recv_mutex); - LOCK(m_recv_mutex); - hdrbuf.SetVersion(nVersionIn); - vRecv.SetVersion(nVersionIn); - } - bool ReceivedBytes(Span& msg_bytes) override EXCLUSIVE_LOCKS_REQUIRED(!m_recv_mutex) { AssertLockNotHeld(m_recv_mutex); @@ -452,7 +467,221 @@ public: CNetMessage GetReceivedMessage(std::chrono::microseconds time, bool& reject_message) override EXCLUSIVE_LOCKS_REQUIRED(!m_recv_mutex); bool SetMessageToSend(CSerializedNetMsg& msg) noexcept override EXCLUSIVE_LOCKS_REQUIRED(!m_send_mutex); - BytesToSend GetBytesToSend() const noexcept override EXCLUSIVE_LOCKS_REQUIRED(!m_send_mutex); + BytesToSend GetBytesToSend(bool have_next_message) const noexcept override EXCLUSIVE_LOCKS_REQUIRED(!m_send_mutex); + void MarkBytesSent(size_t bytes_sent) noexcept override EXCLUSIVE_LOCKS_REQUIRED(!m_send_mutex); + size_t GetSendMemoryUsage() const noexcept override EXCLUSIVE_LOCKS_REQUIRED(!m_send_mutex); +}; + +class V2Transport final : public Transport +{ +private: + /** Contents of the version packet to send. BIP324 stipulates that senders should leave this + * empty, and receivers should ignore it. Future extensions can change what is sent as long as + * an empty version packet contents is interpreted as no extensions supported. */ + static constexpr std::array VERSION_CONTENTS = {}; + + /** The length of the V1 prefix to match bytes initially received by responders with to + * determine if their peer is speaking V1 or V2. */ + static constexpr size_t V1_PREFIX_LEN = 12; + + // The sender side and receiver side of V2Transport are state machines that are transitioned + // through, based on what has been received. The receive state corresponds to the contents of, + // and bytes received to, the receive buffer. The send state controls what can be appended to + // the send buffer and what can be sent from it. + + /** State type that defines the current contents of the receive buffer and/or how the next + * received bytes added to it will be interpreted. + * + * Diagram: + * + * start(responder) + * | + * | start(initiator) /---------\ + * | | | | + * v v v | + * KEY_MAYBE_V1 -> KEY -> GARB_GARBTERM -> GARBAUTH -> VERSION -> APP -> APP_READY + * | + * \-------> V1 + */ + enum class RecvState : uint8_t { + /** (Responder only) either v2 public key or v1 header. + * + * This is the initial state for responders, before data has been received to distinguish + * v1 from v2 connections. When that happens, the state becomes either KEY (for v2) or V1 + * (for v1). */ + KEY_MAYBE_V1, + + /** Public key. + * + * This is the initial state for initiators, during which the other side's public key is + * received. When that information arrives, the ciphers get initialized and the state + * becomes GARB_GARBTERM. */ + KEY, + + /** Garbage and garbage terminator. + * + * Whenever a byte is received, the last 16 bytes are compared with the expected garbage + * terminator. When that happens, the state becomes GARBAUTH. If no matching terminator is + * received in 4111 bytes (4095 for the maximum garbage length, and 16 bytes for the + * terminator), the connection aborts. */ + GARB_GARBTERM, + + /** Garbage authentication packet. + * + * A packet is received, and decrypted/verified with AAD set to the garbage received during + * the GARB_GARBTERM state. If that succeeds, the state becomes VERSION. If it fails the + * connection aborts. */ + GARBAUTH, + + /** Version packet. + * + * A packet is received, and decrypted/verified. If that succeeds, the state becomes APP, + * and the decrypted contents is interpreted as version negotiation (currently, that means + * ignoring it, but it can be used for negotiating future extensions). If it fails, the + * connection aborts. */ + VERSION, + + /** Application packet. + * + * A packet is received, and decrypted/verified. If that succeeds, the state becomes + * APP_READY and the decrypted contents is kept in m_recv_decode_buffer until it is + * retrieved as a message by GetMessage(). */ + APP, + + /** Nothing (an application packet is available for GetMessage()). + * + * Nothing can be received in this state. When the message is retrieved by GetMessage, + * the state becomes APP again. */ + APP_READY, + + /** Nothing (this transport is using v1 fallback). + * + * All receive operations are redirected to m_v1_fallback. */ + V1, + }; + + /** State type that controls the sender side. + * + * Diagram: + * + * start(responder) + * | + * | start(initiator) + * | | + * v v + * MAYBE_V1 -> AWAITING_KEY -> READY + * | + * \-----> V1 + */ + enum class SendState : uint8_t { + /** (Responder only) Not sending until v1 or v2 is detected. + * + * This is the initial state for responders. The send buffer contains the public key to + * send, but nothing is sent in this state yet. When the receiver determines whether this + * is a V1 or V2 connection, the sender state becomes AWAITING_KEY (for v2) or V1 (for v1). + */ + MAYBE_V1, + + /** Waiting for the other side's public key. + * + * This is the initial state for initiators. The public key is sent out. When the receiver + * receives the other side's public key and transitions to GARB_GARBTERM, the sender state + * becomes READY. */ + AWAITING_KEY, + + /** Normal sending state. + * + * In this state, the ciphers are initialized, so packets can be sent. When this state is + * entered, the garbage, garbage terminator, garbage authentication packet, and version + * packet are appended to the send buffer (in addition to the key which may still be + * there). In this state a message can be provided if the send buffer is empty. */ + READY, + + /** This transport is using v1 fallback. + * + * All send operations are redirected to m_v1_fallback. */ + V1, + }; + + /** Cipher state. */ + BIP324Cipher m_cipher; + /** Whether we are the initiator side. */ + const bool m_initiating; + /** NodeId (for debug logging). */ + const NodeId m_nodeid; + /** Encapsulate a V1Transport to fall back to. */ + V1Transport m_v1_fallback; + + /** Lock for receiver-side fields. */ + mutable Mutex m_recv_mutex ACQUIRED_BEFORE(m_send_mutex); + /** In {GARBAUTH, VERSION, APP}, the decrypted packet length, if m_recv_buffer.size() >= + * BIP324Cipher::LENGTH_LEN. Unspecified otherwise. */ + uint32_t m_recv_len GUARDED_BY(m_recv_mutex) {0}; + /** Receive buffer; meaning is determined by m_recv_state. */ + std::vector m_recv_buffer GUARDED_BY(m_recv_mutex); + /** During GARBAUTH, the garbage received during GARB_GARBTERM. */ + std::vector m_recv_garbage GUARDED_BY(m_recv_mutex); + /** Buffer to put decrypted contents in, for converting to CNetMessage. */ + std::vector m_recv_decode_buffer GUARDED_BY(m_recv_mutex); + /** Deserialization type. */ + const int m_recv_type; + /** Deserialization version number. */ + const int m_recv_version; + /** Current receiver state. */ + RecvState m_recv_state GUARDED_BY(m_recv_mutex); + + /** Lock for sending-side fields. If both sending and receiving fields are accessed, + * m_recv_mutex must be acquired before m_send_mutex. */ + mutable Mutex m_send_mutex ACQUIRED_AFTER(m_recv_mutex); + /** The send buffer; meaning is determined by m_send_state. */ + std::vector m_send_buffer GUARDED_BY(m_send_mutex); + /** How many bytes from the send buffer have been sent so far. */ + uint32_t m_send_pos GUARDED_BY(m_send_mutex) {0}; + /** Type of the message being sent. */ + std::string m_send_type GUARDED_BY(m_send_mutex); + /** Current sender state. */ + SendState m_send_state GUARDED_BY(m_send_mutex); + + /** Change the receive state. */ + void SetReceiveState(RecvState recv_state) noexcept EXCLUSIVE_LOCKS_REQUIRED(m_recv_mutex); + /** Change the send state. */ + void SetSendState(SendState send_state) noexcept EXCLUSIVE_LOCKS_REQUIRED(m_send_mutex); + /** Given a packet's contents, find the message type (if valid), and strip it from contents. */ + static std::optional GetMessageType(Span& contents) noexcept; + /** Determine how many received bytes can be processed in one go (not allowed in V1 state). */ + size_t GetMaxBytesToProcess() noexcept EXCLUSIVE_LOCKS_REQUIRED(m_recv_mutex); + /** Process bytes in m_recv_buffer, while in KEY_MAYBE_V1 state. */ + void ProcessReceivedMaybeV1Bytes() noexcept EXCLUSIVE_LOCKS_REQUIRED(m_recv_mutex, !m_send_mutex); + /** Process bytes in m_recv_buffer, while in KEY state. */ + bool ProcessReceivedKeyBytes() noexcept EXCLUSIVE_LOCKS_REQUIRED(m_recv_mutex, !m_send_mutex); + /** Process bytes in m_recv_buffer, while in GARB_GARBTERM state. */ + bool ProcessReceivedGarbageBytes() noexcept EXCLUSIVE_LOCKS_REQUIRED(m_recv_mutex); + /** Process bytes in m_recv_buffer, while in GARBAUTH/VERSION/APP state. */ + bool ProcessReceivedPacketBytes() noexcept EXCLUSIVE_LOCKS_REQUIRED(m_recv_mutex); + +public: + static constexpr uint32_t MAX_GARBAGE_LEN = 4095; + + /** Construct a V2 transport with securely generated random keys. + * + * @param[in] nodeid the node's NodeId (only for debug log output). + * @param[in] initiating whether we are the initiator side. + * @param[in] type_in the serialization type of returned CNetMessages. + * @param[in] version_in the serialization version of returned CNetMessages. + */ + V2Transport(NodeId nodeid, bool initiating, int type_in, int version_in) noexcept; + + /** Construct a V2 transport with specified keys and garbage (test use only). */ + V2Transport(NodeId nodeid, bool initiating, int type_in, int version_in, const CKey& key, Span ent32, Span garbage) noexcept; + + // Receive side functions. + bool ReceivedMessageComplete() const noexcept override EXCLUSIVE_LOCKS_REQUIRED(!m_recv_mutex); + bool ReceivedBytes(Span& msg_bytes) noexcept override EXCLUSIVE_LOCKS_REQUIRED(!m_recv_mutex, !m_send_mutex); + CNetMessage GetReceivedMessage(std::chrono::microseconds time, bool& reject_message) noexcept override EXCLUSIVE_LOCKS_REQUIRED(!m_recv_mutex); + + // Send side functions. + bool SetMessageToSend(CSerializedNetMsg& msg) noexcept override EXCLUSIVE_LOCKS_REQUIRED(!m_send_mutex); + BytesToSend GetBytesToSend(bool have_next_message) const noexcept override EXCLUSIVE_LOCKS_REQUIRED(!m_send_mutex); void MarkBytesSent(size_t bytes_sent) noexcept override EXCLUSIVE_LOCKS_REQUIRED(!m_send_mutex); size_t GetSendMemoryUsage() const noexcept override EXCLUSIVE_LOCKS_REQUIRED(!m_send_mutex); }; diff --git a/src/pubkey.cpp b/src/pubkey.cpp index 3a9c9ced37..54363637d4 100644 --- a/src/pubkey.cpp +++ b/src/pubkey.cpp @@ -258,6 +258,12 @@ bool CPubKey::Derive(CPubKey& pubkeyChild, ChainCode &ccChild, unsigned int nChi return true; } +EllSwiftPubKey::EllSwiftPubKey(Span ellswift) noexcept +{ + assert(ellswift.size() == SIZE); + std::copy(ellswift.begin(), ellswift.end(), m_pubkey.begin()); +} + CPubKey EllSwiftPubKey::Decode() const { secp256k1_pubkey pubkey; diff --git a/src/pubkey.h b/src/pubkey.h index 062b4946c4..14b2956cfe 100644 --- a/src/pubkey.h +++ b/src/pubkey.h @@ -217,8 +217,7 @@ public: EllSwiftPubKey() noexcept = default; /** Construct a new ellswift public key from a given serialization. */ - EllSwiftPubKey(const std::array& ellswift) : - m_pubkey(ellswift) {} + EllSwiftPubKey(Span ellswift) noexcept; /** Decode to normal compressed CPubKey (for debugging purposes). */ CPubKey Decode() const; diff --git a/src/test/bip324_tests.cpp b/src/test/bip324_tests.cpp index 309b89962d..7d651d72b3 100644 --- a/src/test/bip324_tests.cpp +++ b/src/test/bip324_tests.cpp @@ -37,14 +37,8 @@ void TestBIP324PacketVector( { // Convert input from hex to char/byte vectors/arrays. const auto in_priv_ours = ParseHex(in_priv_ours_hex); - const auto in_ellswift_ours_vec = ParseHex(in_ellswift_ours_hex); - assert(in_ellswift_ours_vec.size() == 64); - std::array in_ellswift_ours; - std::copy(in_ellswift_ours_vec.begin(), in_ellswift_ours_vec.end(), in_ellswift_ours.begin()); - const auto in_ellswift_theirs_vec = ParseHex(in_ellswift_theirs_hex); - assert(in_ellswift_theirs_vec.size() == 64); - std::array in_ellswift_theirs; - std::copy(in_ellswift_theirs_vec.begin(), in_ellswift_theirs_vec.end(), in_ellswift_theirs.begin()); + const auto in_ellswift_ours = ParseHex(in_ellswift_ours_hex); + const auto in_ellswift_theirs = ParseHex(in_ellswift_theirs_hex); const auto in_contents = ParseHex(in_contents_hex); const auto in_aad = ParseHex(in_aad_hex); const auto mid_send_garbage = ParseHex(mid_send_garbage_hex); diff --git a/src/test/fuzz/p2p_transport_serialization.cpp b/src/test/fuzz/p2p_transport_serialization.cpp index 1931562f5a..e7a422fff5 100644 --- a/src/test/fuzz/p2p_transport_serialization.cpp +++ b/src/test/fuzz/p2p_transport_serialization.cpp @@ -22,6 +22,7 @@ std::vector g_all_messages; void initialize_p2p_transport_serialization() { + ECC_Start(); SelectParams(CBaseChainParams::REGTEST); g_all_messages = getAllNetMessageTypes(); std::sort(g_all_messages.begin(), g_all_messages.end()); @@ -87,7 +88,7 @@ FUZZ_TARGET_INIT(p2p_transport_serialization, initialize_p2p_transport_serializa assert(queued); std::optional known_more; while (true) { - const auto& [to_send, more, _msg_type] = send_transport.GetBytesToSend(); + const auto& [to_send, more, _msg_type] = send_transport.GetBytesToSend(false); if (known_more) assert(!to_send.empty() == *known_more); if (to_send.empty()) break; send_transport.MarkBytesSent(to_send.size()); @@ -119,11 +120,13 @@ void SimulationTest(Transport& initiator, Transport& responder, R& rng, FuzzedDa // Vectors with bytes last returned by GetBytesToSend() on transport[i]. std::array, 2> to_send; - // Last returned 'more' values (if still relevant) by transport[i]->GetBytesToSend(). - std::array, 2> last_more; + // Last returned 'more' values (if still relevant) by transport[i]->GetBytesToSend(), for + // both have_next_message false and true. + std::array, 2> last_more, last_more_next; - // Whether more bytes to be sent are expected on transport[i]. - std::array, 2> expect_more; + // Whether more bytes to be sent are expected on transport[i], before and after + // SetMessageToSend(). + std::array, 2> expect_more, expect_more_next; // Function to consume a message type. auto msg_type_fn = [&]() { @@ -172,18 +175,27 @@ void SimulationTest(Transport& initiator, Transport& responder, R& rng, FuzzedDa // Wrapper around transport[i]->GetBytesToSend() that performs sanity checks. auto bytes_to_send_fn = [&](int side) -> Transport::BytesToSend { - const auto& [bytes, more, msg_type] = transports[side]->GetBytesToSend(); + // Invoke GetBytesToSend twice (for have_next_message = {false, true}). This function does + // not modify state (it's const), and only the "more" return value should differ between + // the calls. + const auto& [bytes, more_nonext, msg_type] = transports[side]->GetBytesToSend(false); + const auto& [bytes_next, more_next, msg_type_next] = transports[side]->GetBytesToSend(true); // Compare with expected more. if (expect_more[side].has_value()) assert(!bytes.empty() == *expect_more[side]); + // Verify consistency between the two results. + assert(bytes == bytes_next); + assert(msg_type == msg_type_next); + if (more_nonext) assert(more_next); // Compare with previously reported output. assert(to_send[side].size() <= bytes.size()); assert(to_send[side] == Span{bytes}.first(to_send[side].size())); to_send[side].resize(bytes.size()); std::copy(bytes.begin(), bytes.end(), to_send[side].begin()); - // Remember 'more' result. - last_more[side] = {more}; + // Remember 'more' results. + last_more[side] = {more_nonext}; + last_more_next[side] = {more_next}; // Return. - return {bytes, more, msg_type}; + return {bytes, more_nonext, msg_type}; }; // Function to make side send a new message. @@ -194,7 +206,8 @@ void SimulationTest(Transport& initiator, Transport& responder, R& rng, FuzzedDa CSerializedNetMsg msg = next_msg[side].Copy(); bool queued = transports[side]->SetMessageToSend(msg); // Update expected more data. - expect_more[side] = std::nullopt; + expect_more[side] = expect_more_next[side]; + expect_more_next[side] = std::nullopt; // Verify consistency of GetBytesToSend after SetMessageToSend bytes_to_send_fn(/*side=*/side); if (queued) { @@ -218,6 +231,7 @@ void SimulationTest(Transport& initiator, Transport& responder, R& rng, FuzzedDa // If all to-be-sent bytes were sent, move last_more data to expect_more data. if (send_now == bytes.size()) { expect_more[side] = last_more[side]; + expect_more_next[side] = last_more_next[side]; } // Remove the bytes from the last reported to-be-sent vector. assert(to_send[side].size() >= send_now); @@ -246,6 +260,7 @@ void SimulationTest(Transport& initiator, Transport& responder, R& rng, FuzzedDa // Clear cached expected 'more' information: if certainly no more data was to be sent // before, receiving bytes makes this uncertain. if (expect_more[!side] == false) expect_more[!side] = std::nullopt; + if (expect_more_next[!side] == false) expect_more_next[!side] = std::nullopt; // Verify consistency of GetBytesToSend after ReceivedBytes bytes_to_send_fn(/*side=*/!side); bool progress = to_recv.size() < old_len; @@ -315,6 +330,40 @@ std::unique_ptr MakeV1Transport(NodeId nodeid) noexcept return std::make_unique(nodeid, SER_NETWORK, INIT_PROTO_VERSION); } +template +std::unique_ptr MakeV2Transport(NodeId nodeid, bool initiator, RNG& rng, FuzzedDataProvider& provider) +{ + // Retrieve key + auto key = ConsumePrivateKey(provider); + if (!key.IsValid()) return {}; + // Construct garbage + size_t garb_len = provider.ConsumeIntegralInRange(0, V2Transport::MAX_GARBAGE_LEN); + std::vector garb; + if (garb_len <= 64) { + // When the garbage length is up to 64 bytes, read it directly from the fuzzer input. + garb = provider.ConsumeBytes(garb_len); + garb.resize(garb_len); + } else { + // If it's longer, generate it from the RNG. This avoids having large amounts of + // (hopefully) irrelevant data needing to be stored in the fuzzer data. + for (auto& v : garb) v = uint8_t(rng()); + } + // Retrieve entropy + auto ent = provider.ConsumeBytes(32); + ent.resize(32); + // Use as entropy SHA256(ent || garbage). This prevents a situation where the fuzzer manages to + // include the garbage terminator (which is a function of both ellswift keys) in the garbage. + // This is extremely unlikely (~2^-116) with random keys/garbage, but the fuzzer can choose + // both non-randomly and dependently. Since the entropy is hashed anyway inside the ellswift + // computation, no coverage should be lost by using a hash as entropy, and it removes the + // possibility of garbage that happens to contain what is effectively a hash of the keys. + CSHA256().Write(UCharCast(ent.data()), ent.size()) + .Write(garb.data(), garb.size()) + .Finalize(UCharCast(ent.data())); + + return std::make_unique(nodeid, initiator, SER_NETWORK, INIT_PROTO_VERSION, key, ent, garb); +} + } // namespace FUZZ_TARGET_INIT(p2p_transport_bidirectional, initialize_p2p_transport_serialization) @@ -327,3 +376,25 @@ FUZZ_TARGET_INIT(p2p_transport_bidirectional, initialize_p2p_transport_serializa if (!t1 || !t2) return; SimulationTest(*t1, *t2, rng, provider); } + +FUZZ_TARGET_INIT(p2p_transport_bidirectional_v2, initialize_p2p_transport_serialization) +{ + // Test with two V2 transports talking to each other. + FuzzedDataProvider provider{buffer.data(), buffer.size()}; + XoRoShiRo128PlusPlus rng(provider.ConsumeIntegral()); + auto t1 = MakeV2Transport(NodeId{0}, true, rng, provider); + auto t2 = MakeV2Transport(NodeId{1}, false, rng, provider); + if (!t1 || !t2) return; + SimulationTest(*t1, *t2, rng, provider); +} + +FUZZ_TARGET_INIT(p2p_transport_bidirectional_v1v2, initialize_p2p_transport_serialization) +{ + // Test with a V1 initiator talking to a V2 responder. + FuzzedDataProvider provider{buffer.data(), buffer.size()}; + XoRoShiRo128PlusPlus rng(provider.ConsumeIntegral()); + auto t1 = MakeV1Transport(NodeId{0}); + auto t2 = MakeV2Transport(NodeId{1}, false, rng, provider); + if (!t1 || !t2) return; + SimulationTest(*t1, *t2, rng, provider); +} diff --git a/src/test/net_tests.cpp b/src/test/net_tests.cpp index d6235ce623..d7c2870b7a 100644 --- a/src/test/net_tests.cpp +++ b/src/test/net_tests.cpp @@ -1013,4 +1013,530 @@ BOOST_AUTO_TEST_CASE(advertise_local_address) RemoveLocal(addr_cjdns); } +namespace { + +/** A class for scenario-based tests of V2Transport + * + * Each V2TransportTester encapsulates a V2Transport (the one being tested), and can be told to + * interact with it. To do so, it also encapsulates a BIP324Cipher to act as the other side. A + * second V2Transport is not used, as doing so would not permit scenarios that involve sending + * invalid data, or ones scenarios using BIP324 features that are not implemented on the sending + * side (like decoy packets). + */ +class V2TransportTester +{ + V2Transport m_transport; //!< V2Transport being tested + BIP324Cipher m_cipher; //!< Cipher to help with the other side + bool m_test_initiator; //!< Whether m_transport is the initiator (true) or responder (false) + + std::vector m_sent_garbage; //!< The garbage we've sent to m_transport. + std::vector m_to_send; //!< Bytes we have queued up to send to m_transport. + std::vector m_received; //!< Bytes we have received from m_transport. + std::deque m_msg_to_send; //!< Messages to be sent *by* m_transport to us. + +public: + /** Construct a tester object. test_initiator: whether the tested transport is initiator. */ + V2TransportTester(bool test_initiator) : + m_transport(0, test_initiator, SER_NETWORK, INIT_PROTO_VERSION), + m_test_initiator(test_initiator) {} + + /** Data type returned by Interact: + * + * - std::nullopt: transport error occurred + * - otherwise: a vector of + * - std::nullopt: invalid message received + * - otherwise: a CNetMessage retrieved + */ + using InteractResult = std::optional>>; + + /** Send/receive scheduled/available bytes and messages. + * + * This is the only function that interacts with the transport being tested; everything else is + * scheduling things done by Interact(), or processing things learned by it. + */ + InteractResult Interact() + { + std::vector> ret; + while (true) { + bool progress{false}; + // Send bytes from m_to_send to the transport. + if (!m_to_send.empty()) { + Span to_send = Span{m_to_send}.first(1 + InsecureRandRange(m_to_send.size())); + size_t old_len = to_send.size(); + if (!m_transport.ReceivedBytes(to_send)) { + return std::nullopt; // transport error occurred + } + if (old_len != to_send.size()) { + progress = true; + m_to_send.erase(m_to_send.begin(), m_to_send.begin() + (old_len - to_send.size())); + } + } + // Retrieve messages received by the transport. + if (m_transport.ReceivedMessageComplete() && (!progress || InsecureRandBool())) { + bool reject{false}; + auto msg = m_transport.GetReceivedMessage({}, reject); + if (reject) { + ret.push_back(std::nullopt); + } else { + ret.push_back(std::move(msg)); + } + progress = true; + } + // Enqueue a message to be sent by the transport to us. + if (!m_msg_to_send.empty() && (!progress || InsecureRandBool())) { + if (m_transport.SetMessageToSend(m_msg_to_send.front())) { + m_msg_to_send.pop_front(); + progress = true; + } + } + // Receive bytes from the transport. + const auto& [recv_bytes, _more, _msg_type] = m_transport.GetBytesToSend(!m_msg_to_send.empty()); + if (!recv_bytes.empty() && (!progress || InsecureRandBool())) { + size_t to_receive = 1 + InsecureRandRange(recv_bytes.size()); + m_received.insert(m_received.end(), recv_bytes.begin(), recv_bytes.begin() + to_receive); + progress = true; + m_transport.MarkBytesSent(to_receive); + } + if (!progress) break; + } + return ret; + } + + /** Expose the cipher. */ + BIP324Cipher& GetCipher() { return m_cipher; } + + /** Schedule bytes to be sent to the transport. */ + void Send(Span data) + { + m_to_send.insert(m_to_send.end(), data.begin(), data.end()); + } + + /** Send V1 version message header to the transport. */ + void SendV1Version(const CMessageHeader::MessageStartChars& magic) + { + CMessageHeader hdr(magic, "version", 126 + InsecureRandRange(11)); + CDataStream ser(SER_NETWORK, CLIENT_VERSION); + ser << hdr; + m_to_send.insert(m_to_send.end(), UCharCast(ser.data()), UCharCast(ser.data() + ser.size())); + } + + /** Schedule bytes to be sent to the transport. */ + void Send(Span data) { Send(MakeUCharSpan(data)); } + + /** Schedule our ellswift key to be sent to the transport. */ + void SendKey() { Send(m_cipher.GetOurPubKey()); } + + /** Schedule specified garbage to be sent to the transport. */ + void SendGarbage(Span garbage) + { + // Remember the specified garbage (so we can use it for constructing the garbage + // authentication packet). + m_sent_garbage.assign(garbage.begin(), garbage.end()); + // Schedule it for sending. + Send(m_sent_garbage); + } + + /** Schedule garbage (of specified length) to be sent to the transport. */ + void SendGarbage(size_t garbage_len) + { + // Generate random garbage and send it. + SendGarbage(g_insecure_rand_ctx.randbytes(garbage_len)); + } + + /** Schedule garbage (with valid random length) to be sent to the transport. */ + void SendGarbage() + { + SendGarbage(InsecureRandRange(V2Transport::MAX_GARBAGE_LEN + 1)); + } + + /** Schedule a message to be sent to us by the transport. */ + void AddMessage(std::string m_type, std::vector payload) + { + CSerializedNetMsg msg; + msg.m_type = std::move(m_type); + msg.data = std::move(payload); + m_msg_to_send.push_back(std::move(msg)); + } + + /** Expect ellswift key to have been received from transport and process it. + * + * Many other V2TransportTester functions cannot be called until after ReceiveKey() has been + * called, as no encryption keys are set up before that point. + */ + void ReceiveKey() + { + // When processing a key, enough bytes need to have been received already. + BOOST_REQUIRE(m_received.size() >= EllSwiftPubKey::size()); + // Initialize the cipher using it (acting as the opposite side of the tested transport). + m_cipher.Initialize(MakeByteSpan(m_received).first(EllSwiftPubKey::size()), !m_test_initiator); + // Strip the processed bytes off the front of the receive buffer. + m_received.erase(m_received.begin(), m_received.begin() + EllSwiftPubKey::size()); + } + + /** Schedule an encrypted packet with specified content/aad/ignore to be sent to transport + * (only after ReceiveKey). */ + void SendPacket(Span content, Span aad = {}, bool ignore = false) + { + // Use cipher to construct ciphertext. + std::vector ciphertext; + ciphertext.resize(content.size() + BIP324Cipher::EXPANSION); + m_cipher.Encrypt( + /*contents=*/MakeByteSpan(content), + /*aad=*/MakeByteSpan(aad), + /*ignore=*/ignore, + /*output=*/ciphertext); + // Schedule it for sending. + Send(ciphertext); + } + + /** Schedule garbage terminator and authentication packet to be sent to the transport (only + * after ReceiveKey). */ + void SendGarbageTermAuth(size_t garb_auth_data_len = 0, bool garb_auth_ignore = false) + { + // Generate random data to include in the garbage authentication packet (ignored by peer). + auto garb_auth_data = g_insecure_rand_ctx.randbytes(garb_auth_data_len); + // Schedule the garbage terminator to be sent. + Send(m_cipher.GetSendGarbageTerminator()); + // Schedule the garbage authentication packet to be sent. + SendPacket(/*content=*/garb_auth_data, /*aad=*/m_sent_garbage, /*ignore=*/garb_auth_ignore); + } + + /** Schedule version packet to be sent to the transport (only after ReceiveKey). */ + void SendVersion(Span version_data = {}, bool vers_ignore = false) + { + SendPacket(/*content=*/version_data, /*aad=*/{}, /*ignore=*/vers_ignore); + } + + /** Expect a packet to have been received from transport, process it, and return its contents + * (only after ReceiveKey). By default, decoys are skipped. */ + std::vector ReceivePacket(Span aad = {}, bool skip_decoy = true) + { + std::vector contents; + // Loop as long as there are ignored packets that are to be skipped. + while (true) { + // When processing a packet, at least enough bytes for its length descriptor must be received. + BOOST_REQUIRE(m_received.size() >= BIP324Cipher::LENGTH_LEN); + // Decrypt the content length. + size_t size = m_cipher.DecryptLength(MakeByteSpan(Span{m_received}.first(BIP324Cipher::LENGTH_LEN))); + // Check that the full packet is in the receive buffer. + BOOST_REQUIRE(m_received.size() >= size + BIP324Cipher::EXPANSION); + // Decrypt the packet contents. + contents.resize(size); + bool ignore{false}; + bool ret = m_cipher.Decrypt( + /*input=*/MakeByteSpan( + Span{m_received}.first(size + BIP324Cipher::EXPANSION).subspan(BIP324Cipher::LENGTH_LEN)), + /*aad=*/aad, + /*ignore=*/ignore, + /*contents=*/MakeWritableByteSpan(contents)); + BOOST_CHECK(ret); + // Strip the processed packet's bytes off the front of the receive buffer. + m_received.erase(m_received.begin(), m_received.begin() + size + BIP324Cipher::EXPANSION); + // Stop if the ignore bit is not set on this packet, or if we choose to not honor it. + if (!ignore || !skip_decoy) break; + } + return contents; + } + + /** Expect garbage, garbage terminator, and garbage auth packet to have been received, and + * process them (only after ReceiveKey). */ + void ReceiveGarbage() + { + // Figure out the garbage length. + size_t garblen; + for (garblen = 0; garblen <= V2Transport::MAX_GARBAGE_LEN; ++garblen) { + BOOST_REQUIRE(m_received.size() >= garblen + BIP324Cipher::GARBAGE_TERMINATOR_LEN); + auto term_span = MakeByteSpan(Span{m_received}.subspan(garblen, BIP324Cipher::GARBAGE_TERMINATOR_LEN)); + if (term_span == m_cipher.GetReceiveGarbageTerminator()) break; + } + // Copy the garbage to a buffer. + std::vector garbage(m_received.begin(), m_received.begin() + garblen); + // Strip garbage + garbage terminator off the front of the receive buffer. + m_received.erase(m_received.begin(), m_received.begin() + garblen + BIP324Cipher::GARBAGE_TERMINATOR_LEN); + // Process the expected garbage authentication packet. Such a packet still functions as one + // even when its ignore bit is set to true, so we do not skip decoy packets here. + ReceivePacket(/*aad=*/MakeByteSpan(garbage), /*skip_decoy=*/false); + } + + /** Expect version packet to have been received, and process it (only after ReceiveKey). */ + void ReceiveVersion() + { + auto contents = ReceivePacket(); + // Version packets from real BIP324 peers are expected to be empty, despite the fact that + // this class supports *sending* non-empty version packets (to test that BIP324 peers + // correctly ignore version packet contents). + BOOST_CHECK(contents.empty()); + } + + /** Expect application packet to have been received, with specified short id and payload. + * (only after ReceiveKey). */ + void ReceiveMessage(uint8_t short_id, Span payload) + { + auto ret = ReceivePacket(); + BOOST_CHECK(ret.size() == payload.size() + 1); + BOOST_CHECK(ret[0] == short_id); + BOOST_CHECK(Span{ret}.subspan(1) == payload); + } + + /** Expect application packet to have been received, with specified 12-char message type and + * payload (only after ReceiveKey). */ + void ReceiveMessage(const std::string& m_type, Span payload) + { + auto ret = ReceivePacket(); + BOOST_REQUIRE(ret.size() == payload.size() + 1 + CMessageHeader::COMMAND_SIZE); + BOOST_CHECK(ret[0] == 0); + for (unsigned i = 0; i < 12; ++i) { + if (i < m_type.size()) { + BOOST_CHECK(ret[1 + i] == m_type[i]); + } else { + BOOST_CHECK(ret[1 + i] == 0); + } + } + BOOST_CHECK(Span{ret}.subspan(1 + CMessageHeader::COMMAND_SIZE) == payload); + } + + /** Schedule an encrypted packet with specified message type and payload to be sent to + * transport (only after ReceiveKey). */ + void SendMessage(std::string mtype, Span payload) + { + // Construct contents consisting of 0x00 + 12-byte message type + payload. + std::vector contents(1 + CMessageHeader::COMMAND_SIZE + payload.size()); + std::copy(mtype.begin(), mtype.end(), reinterpret_cast(contents.data() + 1)); + std::copy(payload.begin(), payload.end(), contents.begin() + 1 + CMessageHeader::COMMAND_SIZE); + // Send a packet with that as contents. + SendPacket(contents); + } + + /** Schedule an encrypted packet with specified short message id and payload to be sent to + * transport (only after ReceiveKey). */ + void SendMessage(uint8_t short_id, Span payload) + { + // Construct contents consisting of short_id + payload. + std::vector contents(1 + payload.size()); + contents[0] = short_id; + std::copy(payload.begin(), payload.end(), contents.begin() + 1); + // Send a packet with that as contents. + SendPacket(contents); + } + + /** Introduce a bit error in the data scheduled to be sent. */ + void Damage() + { + m_to_send[InsecureRandRange(m_to_send.size())] ^= (uint8_t{1} << InsecureRandRange(8)); + } +}; + +} // namespace + +BOOST_AUTO_TEST_CASE(v2transport_test) +{ + // A mostly normal scenario, testing a transport in initiator mode. + for (int i = 0; i < 10; ++i) { + V2TransportTester tester(true); + auto ret = tester.Interact(); + BOOST_REQUIRE(ret && ret->empty()); + tester.SendKey(); + tester.SendGarbage(); + tester.ReceiveKey(); + tester.SendGarbageTermAuth(); + tester.SendVersion(); + ret = tester.Interact(); + BOOST_REQUIRE(ret && ret->empty()); + tester.ReceiveGarbage(); + tester.ReceiveVersion(); + auto msg_data_1 = g_insecure_rand_ctx.randbytes(InsecureRandRange(100000)); + auto msg_data_2 = g_insecure_rand_ctx.randbytes(InsecureRandRange(1000)); + tester.SendMessage(uint8_t(4), msg_data_1); // cmpctblock short id + tester.SendMessage(0, {}); // Invalidly encoded message + tester.SendMessage("tx", msg_data_2); // 12-character encoded message type + ret = tester.Interact(); + BOOST_REQUIRE(ret && ret->size() == 3); + BOOST_CHECK((*ret)[0] && (*ret)[0]->m_type == "cmpctblock" && Span{(*ret)[0]->m_recv} == MakeByteSpan(msg_data_1)); + BOOST_CHECK(!(*ret)[1]); + BOOST_CHECK((*ret)[2] && (*ret)[2]->m_type == "tx" && Span{(*ret)[2]->m_recv} == MakeByteSpan(msg_data_2)); + + // Then send a message with a bit error, expecting failure. + tester.SendMessage("bad", msg_data_1); + tester.Damage(); + ret = tester.Interact(); + BOOST_CHECK(!ret); + } + + // Normal scenario, with a transport in responder node. + for (int i = 0; i < 10; ++i) { + V2TransportTester tester(false); + tester.SendKey(); + tester.SendGarbage(); + auto ret = tester.Interact(); + BOOST_REQUIRE(ret && ret->empty()); + tester.ReceiveKey(); + tester.SendGarbageTermAuth(); + tester.SendVersion(); + ret = tester.Interact(); + BOOST_REQUIRE(ret && ret->empty()); + tester.ReceiveGarbage(); + tester.ReceiveVersion(); + auto msg_data_1 = g_insecure_rand_ctx.randbytes(InsecureRandRange(100000)); + auto msg_data_2 = g_insecure_rand_ctx.randbytes(InsecureRandRange(1000)); + tester.SendMessage(uint8_t(14), msg_data_1); // inv short id + tester.SendMessage(uint8_t(19), msg_data_2); // pong short id + ret = tester.Interact(); + BOOST_REQUIRE(ret && ret->size() == 2); + BOOST_CHECK((*ret)[0] && (*ret)[0]->m_type == "inv" && Span{(*ret)[0]->m_recv} == MakeByteSpan(msg_data_1)); + BOOST_CHECK((*ret)[1] && (*ret)[1]->m_type == "pong" && Span{(*ret)[1]->m_recv} == MakeByteSpan(msg_data_2)); + + // Then send a too-large message. + auto msg_data_3 = g_insecure_rand_ctx.randbytes(4005000); + tester.SendMessage(uint8_t(11), msg_data_3); // getdata short id + ret = tester.Interact(); + BOOST_CHECK(!ret); + } + + // Various valid but unusual scenarios. + for (int i = 0; i < 50; ++i) { + /** Whether an initiator or responder is being tested. */ + bool initiator = InsecureRandBool(); + /** Use either 0 bytes or the maximum possible (4095 bytes) garbage length. */ + size_t garb_len = InsecureRandBool() ? 0 : V2Transport::MAX_GARBAGE_LEN; + /** Sometimes, use non-empty contents in the garbage authentication packet (which is to be ignored). */ + size_t garb_auth_data_len = InsecureRandBool() ? 0 : InsecureRandRange(100000); + /** Whether to set the ignore bit on the garbage authentication packet (it still functions as garbage authentication). */ + bool garb_ignore = InsecureRandBool(); + /** How many decoy packets to send before the version packet. */ + unsigned num_ignore_version = InsecureRandRange(10); + /** What data to send in the version packet (ignored by BIP324 peers, but reserved for future extensions). */ + auto ver_data = g_insecure_rand_ctx.randbytes(InsecureRandBool() ? 0 : InsecureRandRange(1000)); + /** Whether to immediately send key and garbage out (required for responders, optional otherwise). */ + bool send_immediately = !initiator || InsecureRandBool(); + /** How many decoy packets to send before the first and second real message. */ + unsigned num_decoys_1 = InsecureRandRange(1000), num_decoys_2 = InsecureRandRange(1000); + V2TransportTester tester(initiator); + if (send_immediately) { + tester.SendKey(); + tester.SendGarbage(garb_len); + } + auto ret = tester.Interact(); + BOOST_REQUIRE(ret && ret->empty()); + if (!send_immediately) { + tester.SendKey(); + tester.SendGarbage(garb_len); + } + tester.ReceiveKey(); + tester.SendGarbageTermAuth(garb_auth_data_len, garb_ignore); + for (unsigned v = 0; v < num_ignore_version; ++v) { + size_t ver_ign_data_len = InsecureRandBool() ? 0 : InsecureRandRange(1000); + auto ver_ign_data = g_insecure_rand_ctx.randbytes(ver_ign_data_len); + tester.SendVersion(ver_ign_data, true); + } + tester.SendVersion(ver_data, false); + ret = tester.Interact(); + BOOST_REQUIRE(ret && ret->empty()); + tester.ReceiveGarbage(); + tester.ReceiveVersion(); + for (unsigned d = 0; d < num_decoys_1; ++d) { + auto decoy_data = g_insecure_rand_ctx.randbytes(InsecureRandRange(1000)); + tester.SendPacket(/*content=*/decoy_data, /*aad=*/{}, /*ignore=*/true); + } + auto msg_data_1 = g_insecure_rand_ctx.randbytes(InsecureRandRange(MAX_PROTOCOL_MESSAGE_LENGTH)); + tester.SendMessage(uint8_t(28), msg_data_1); + for (unsigned d = 0; d < num_decoys_2; ++d) { + auto decoy_data = g_insecure_rand_ctx.randbytes(InsecureRandRange(1000)); + tester.SendPacket(/*content=*/decoy_data, /*aad=*/{}, /*ignore=*/true); + } + auto msg_data_2 = g_insecure_rand_ctx.randbytes(InsecureRandRange(1000)); + tester.SendMessage(uint8_t(13), msg_data_2); // headers short id + // Send invalidly-encoded message + tester.SendMessage(std::string("blocktxn\x00\x00\x00a", CMessageHeader::COMMAND_SIZE), {}); + tester.SendMessage("foobar", {}); // test receiving unknown message type + tester.AddMessage("barfoo", {}); // test sending unknown message type + ret = tester.Interact(); + BOOST_REQUIRE(ret && ret->size() == 4); + BOOST_CHECK((*ret)[0] && (*ret)[0]->m_type == "addrv2" && Span{(*ret)[0]->m_recv} == MakeByteSpan(msg_data_1)); + BOOST_CHECK((*ret)[1] && (*ret)[1]->m_type == "headers" && Span{(*ret)[1]->m_recv} == MakeByteSpan(msg_data_2)); + BOOST_CHECK(!(*ret)[2]); + BOOST_CHECK((*ret)[3] && (*ret)[3]->m_type == "foobar" && (*ret)[3]->m_recv.empty()); + tester.ReceiveMessage("barfoo", {}); + } + + // Too long garbage (initiator). + { + V2TransportTester tester(true); + auto ret = tester.Interact(); + BOOST_REQUIRE(ret && ret->empty()); + tester.SendKey(); + tester.SendGarbage(V2Transport::MAX_GARBAGE_LEN + 1); + tester.ReceiveKey(); + tester.SendGarbageTermAuth(); + ret = tester.Interact(); + BOOST_CHECK(!ret); + } + + // Too long garbage (responder). + { + V2TransportTester tester(false); + tester.SendKey(); + tester.SendGarbage(V2Transport::MAX_GARBAGE_LEN + 1); + auto ret = tester.Interact(); + BOOST_REQUIRE(ret && ret->empty()); + tester.ReceiveKey(); + tester.SendGarbageTermAuth(); + ret = tester.Interact(); + BOOST_CHECK(!ret); + } + + // Send garbage that includes the first 15 garbage terminator bytes somewhere. + { + V2TransportTester tester(true); + auto ret = tester.Interact(); + BOOST_REQUIRE(ret && ret->empty()); + tester.SendKey(); + tester.ReceiveKey(); + /** The number of random garbage bytes before the included first 15 bytes of terminator. */ + size_t len_before = InsecureRandRange(V2Transport::MAX_GARBAGE_LEN - 16 + 1); + /** The number of random garbage bytes after it. */ + size_t len_after = InsecureRandRange(V2Transport::MAX_GARBAGE_LEN - 16 - len_before + 1); + // Construct len_before + 16 + len_after random bytes. + auto garbage = g_insecure_rand_ctx.randbytes(len_before + 16 + len_after); + // Replace the designed 16 bytes in the middle with the to-be-sent garbage terminator. + auto garb_term = MakeUCharSpan(tester.GetCipher().GetSendGarbageTerminator()); + std::copy(garb_term.begin(), garb_term.begin() + 16, garbage.begin() + len_before); + // Introduce a bit error in the last byte of that copied garbage terminator, making only + // the first 15 of them match. + garbage[len_before + 15] ^= (uint8_t(1) << InsecureRandRange(8)); + tester.SendGarbage(garbage); + tester.SendGarbageTermAuth(); + tester.SendVersion(); + ret = tester.Interact(); + BOOST_REQUIRE(ret && ret->empty()); + tester.ReceiveGarbage(); + tester.ReceiveVersion(); + auto msg_data_1 = g_insecure_rand_ctx.randbytes(MAX_PROTOCOL_MESSAGE_LENGTH); // test that receiving max size payload works + auto msg_data_2 = g_insecure_rand_ctx.randbytes(MAX_PROTOCOL_MESSAGE_LENGTH); // test that sending max size payload works + tester.SendMessage(uint8_t(InsecureRandRange(223) + 33), {}); // unknown short id + tester.SendMessage(uint8_t(2), msg_data_1); // "block" short id + tester.AddMessage("blocktxn", msg_data_2); // schedule blocktxn to be sent to us + ret = tester.Interact(); + BOOST_REQUIRE(ret && ret->size() == 2); + BOOST_CHECK(!(*ret)[0]); + BOOST_CHECK((*ret)[1] && (*ret)[1]->m_type == "block" && Span{(*ret)[1]->m_recv} == MakeByteSpan(msg_data_1)); + tester.ReceiveMessage(uint8_t(3), msg_data_2); // "blocktxn" short id + } + + // Send correct network's V1 header + { + V2TransportTester tester(false); + tester.SendV1Version(Params().MessageStart()); + auto ret = tester.Interact(); + BOOST_CHECK(ret); + } + + // Send wrong network's V1 header + { + V2TransportTester tester(false); + tester.SendV1Version(CreateChainParams(*m_node.args, CBaseChainParams::MAIN)->MessageStart()); + auto ret = tester.Interact(); + BOOST_CHECK(!ret); + } +} + BOOST_AUTO_TEST_SUITE_END() diff --git a/src/test/util/net.cpp b/src/test/util/net.cpp index e9f43e69cf..ee29613fa0 100644 --- a/src/test/util/net.cpp +++ b/src/test/util/net.cpp @@ -78,7 +78,7 @@ void ConnmanTestMsg::FlushSendBuffer(CNode& node) const node.vSendMsg.clear(); node.m_send_memusage = 0; while (true) { - const auto& [to_send, _more, _msg_type] = node.m_transport->GetBytesToSend(); + const auto& [to_send, _more, _msg_type] = node.m_transport->GetBytesToSend(false); if (to_send.empty()) break; node.m_transport->MarkBytesSent(to_send.size()); } @@ -90,7 +90,7 @@ bool ConnmanTestMsg::ReceiveMsgFrom(CNode& node, CSerializedNetMsg&& ser_msg) co assert(queued); bool complete{false}; while (true) { - const auto& [to_send, _more, _msg_type] = node.m_transport->GetBytesToSend(); + const auto& [to_send, _more, _msg_type] = node.m_transport->GetBytesToSend(false); if (to_send.empty()) break; NodeReceiveMsgBytes(node, to_send, complete); node.m_transport->MarkBytesSent(to_send.size());