diff options
-rw-r--r-- | src/protocol.h | 76 |
1 files changed, 65 insertions, 11 deletions
diff --git a/src/protocol.h b/src/protocol.h index aaa9f1df40..251b8892cf 100644 --- a/src/protocol.h +++ b/src/protocol.h @@ -13,6 +13,7 @@ #include <netaddress.h> #include <primitives/transaction.h> #include <serialize.h> +#include <streams.h> #include <uint256.h> #include <version.h> @@ -358,6 +359,31 @@ class CAddress : public CService { static constexpr uint32_t TIME_INIT{100000000}; + /** Historically, CAddress disk serialization stored the CLIENT_VERSION, optionally OR'ed with + * the ADDRV2_FORMAT flag to indicate V2 serialization. The first field has since been + * disentangled from client versioning, and now instead: + * - The low bits (masked by DISK_VERSION_IGNORE_MASK) store the fixed value DISK_VERSION_INIT, + * (in case any code exists that treats it as a client version) but are ignored on + * deserialization. + * - The high bits (masked by ~DISK_VERSION_IGNORE_MASK) store actual serialization information. + * Only 0 or DISK_VERSION_ADDRV2 (equal to the historical ADDRV2_FORMAT) are valid now, and + * any other value triggers a deserialization failure. Other values can be added later if + * needed. + * + * For disk deserialization, ADDRV2_FORMAT in the stream version signals that ADDRV2 + * deserialization is permitted, but the actual format is determined by the high bits in the + * stored version field. For network serialization, the stream version having ADDRV2_FORMAT or + * not determines the actual format used (as it has no embedded version number). + */ + static constexpr uint32_t DISK_VERSION_INIT{220000}; + static constexpr uint32_t DISK_VERSION_IGNORE_MASK{0b00000000'00000111'11111111'11111111}; + /** The version number written in disk serialized addresses to indicate V2 serializations. + * It must be exactly 1<<29, as that is the value that historical versions used for this + * (they used their internal ADDRV2_FORMAT flag here). */ + static constexpr uint32_t DISK_VERSION_ADDRV2{1 << 29}; + static_assert((DISK_VERSION_INIT & ~DISK_VERSION_IGNORE_MASK) == 0, "DISK_VERSION_INIT must be covered by DISK_VERSION_IGNORE_MASK"); + static_assert((DISK_VERSION_ADDRV2 & DISK_VERSION_IGNORE_MASK) == 0, "DISK_VERSION_ADDRV2 must not be covered by DISK_VERSION_IGNORE_MASK"); + public: CAddress() : CService{} {}; CAddress(CService ipIn, ServiceFlags nServicesIn) : CService{ipIn}, nServices{nServicesIn} {}; @@ -365,22 +391,48 @@ public: SERIALIZE_METHODS(CAddress, obj) { - SER_READ(obj, obj.nTime = TIME_INIT); - int nVersion = s.GetVersion(); + // CAddress has a distinct network serialization and a disk serialization, but it should never + // be hashed (except through CHashWriter in addrdb.cpp, which sets SER_DISK), and it's + // ambiguous what that would mean. Make sure no code relying on that is introduced: + assert(!(s.GetType() & SER_GETHASH)); + bool use_v2; + bool store_time; if (s.GetType() & SER_DISK) { - READWRITE(nVersion); - } - if ((s.GetType() & SER_DISK) || - (nVersion != INIT_PROTO_VERSION && !(s.GetType() & SER_GETHASH))) { + // In the disk serialization format, the encoding (v1 or v2) is determined by a flag version + // that's part of the serialization itself. ADDRV2_FORMAT in the stream version only determines + // whether V2 is chosen/permitted at all. + uint32_t stored_format_version = DISK_VERSION_INIT; + if (s.GetVersion() & ADDRV2_FORMAT) stored_format_version |= DISK_VERSION_ADDRV2; + READWRITE(stored_format_version); + stored_format_version &= ~DISK_VERSION_IGNORE_MASK; // ignore low bits + if (stored_format_version == 0) { + use_v2 = false; + } else if (stored_format_version == DISK_VERSION_ADDRV2 && (s.GetVersion() & ADDRV2_FORMAT)) { + // Only support v2 deserialization if ADDRV2_FORMAT is set. + use_v2 = true; + } else { + throw std::ios_base::failure("Unsupported CAddress disk format version"); + } + store_time = true; + } else { + // In the network serialization format, the encoding (v1 or v2) is determined directly by + // the value of ADDRV2_FORMAT in the stream version, as no explicitly encoded version + // exists in the stream. + assert(s.GetType() & SER_NETWORK); + use_v2 = s.GetVersion() & ADDRV2_FORMAT; // The only time we serialize a CAddress object without nTime is in // the initial VERSION messages which contain two CAddress records. // At that point, the serialization version is INIT_PROTO_VERSION. // After the version handshake, serialization version is >= // MIN_PEER_PROTO_VERSION and all ADDR messages are serialized with // nTime. - READWRITE(obj.nTime); + store_time = s.GetVersion() != INIT_PROTO_VERSION; } - if (nVersion & ADDRV2_FORMAT) { + + SER_READ(obj, obj.nTime = TIME_INIT); + if (store_time) READWRITE(obj.nTime); + // nServices is serialized as CompactSize in V2; as uint64_t in V1. + if (use_v2) { uint64_t services_tmp; SER_WRITE(obj, services_tmp = obj.nServices); READWRITE(Using<CompactSizeFormatter<false>>(services_tmp)); @@ -388,12 +440,14 @@ public: } else { READWRITE(Using<CustomUintFormatter<8>>(obj.nServices)); } - READWRITEAS(CService, obj); + // Invoke V1/V2 serializer for CService parent object. + OverrideStream<Stream> os(&s, s.GetType(), use_v2 ? ADDRV2_FORMAT : 0); + SerReadWriteMany(os, ser_action, ReadWriteAsHelper<CService>(obj)); } - // disk and network only + //! Always included in serialization, except in the network format on INIT_PROTO_VERSION. uint32_t nTime{TIME_INIT}; - + //! Serialized as uint64_t in V1, and as CompactSize in V2. ServiceFlags nServices{NODE_NONE}; }; |