BIP-155 addrv2 + Remove Tor v2 (OnionCat) support#2
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BIP-155 addrv2 + Remove Tor v2 (OnionCat) support#2
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Research-based implementation plan incorporating lessons learned from: - Bitcoin Core PRs #19031, #19954, #20119, #20564 - Zcash issues zcash#5277, zcash#3051 Key issues addressed in plan: - sendaddrv2 timing (send before verack, not after) - Protocol version gating (don't send to old nodes) - Address relay black holes prevention - peers.dat migration strategy - Spam prevention for unknown network types 4-phase implementation over ~4 weeks: 1. Data structures 2. Protocol messages 3. Address manager 4. Testing & hardening 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
- Bump protocol version to 170012 - Add sendaddrv2/addrv2 message handlers - Add BIP155Network enum and address size constants - Implement address serialization for variable-length addresses - Add m_wants_addrv2 flag for peer negotiation - Update address relay logic for addrv2-aware peers - Add -enablebip155 config flag (default: on) - Backward compatible with protocol 170011 peers Tested: Tor v3 onion address advertised, legacy peers receive legacy addr format, unexpected sendaddrv2 from old peers rejected. 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
Accept sendaddrv2 at any time from 170012+ peers, not just before verack. This improves compatibility with implementations that may send sendaddrv2 slightly after verack while still rejecting it from old protocol versions. 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
When -proxy or -onion is set, also configure NET_TORV3 network: - Set proxy for Tor v3 connections - Mark NET_TORV3 as reachable (not limited) This allows the node to make outbound connections to Tor v3 onion addresses and properly display them in getnetworkinfo. 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
This commit completes the BIP-155 implementation by adding proper serialization support for variable-length addresses in peers.dat, enabling Tor v3 addresses to persist across node restarts. Changes aligned with Bitcoin Core's approach (PR #19954, #20284): peers.dat format versioning: - Format byte 0: version (V0_HISTORICAL, V1_DETERMINISTIC, V3_BIP155) - Format byte 1: INCOMPATIBILITY_BASE(32) + lowest_compatible_version - Old nodes see keysize=35 (not 32), fail gracefully with "Incorrect keysize in addrman deserialization" - New nodes detect format and use addrv2 when format >= V3_BIP155 Serialization changes: - src/serialize.h: Add SER_ADDRV2 flag for address serialization - src/netbase.h: CNetAddr/CService serialize in BIP155 format when SER_ADDRV2 flag is set (network_id + CompactSize len + variable addr) - src/protocol.h: CAddress uses CompactSize for services in addrv2 - src/addrman.h: CAddrMan Serialize/Unserialize handle both legacy and addrv2 formats with proper version detection Migration behavior: - Read: Detects old format (keysize=32) and reads legacy 16-byte addrs - Write: Always writes V3_BIP155 format with addrv2 addresses - Backward: Old nodes reject new peers.dat, create fresh database This enables Zclassic nodes to store and relay Tor v3 onion addresses (.onion 56-char), making Zclassic one of the first Zcash-based coins to fully implement BIP-155. 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
Build fixes for the BIP-155 peers.dat implementation:
1. Replace static const with enum for INCOMPATIBILITY_BASE
- static const/constexpr class members require out-of-line definitions
when ODR-used (passed to strprintf varargs)
- Using anonymous enum avoids linker "undefined symbol" errors
- Removed FILE_FORMAT and LOWEST_COMPATIBLE, use V3_BIP155 directly
2. Fix CDataStream buffer access
- CDataStream doesn't have data() method (unlike std::vector)
- Use &ssAddr[0] instead of ssAddr.data() for write() calls
3. Add explicit int casts in strprintf
- Enum values passed to varargs need explicit casting to avoid
format specifier warnings
Tested: peers.dat now correctly writes V3_BIP155 format (03 23 header)
verified by xxd after flush - old format was (01 20), new is (03 23).
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
Two critical bugs were causing peers.dat load failures after addrv2 flush:
1. Missing nVersion read in addrv2 Unserialize (addrman.h)
- CAddress with SER_DISK serializes: nVersion(4) + nTime(4) + nServices + CService
- The addrv2 parsing code was missing the nVersion read, causing stream
position misalignment and "ReadCompactSize(): size too large" errors
- Fixed by adding `int nAddrVersion; s >> nAddrVersion;` before nAddrTime
2. m_net field not set after legacy format deserialization (netbase.h)
- When loading legacy peers.dat, CNetAddr::m_net remained at default NET_IPV4
- This caused GetBIP155Network() to return BIP155_IPV4 for all addresses
- IPv6 addresses were incorrectly serialized as 4-byte IPv4, corrupting data
- Fixed by detecting network type from IP content after legacy FLATDATA read:
IsIPv4() -> NET_IPV4, IsTor() -> NET_ONION, else -> NET_IPV6
Testing verified:
- Legacy peers.dat (01 20) loads correctly, sets proper m_net values
- Addrv2 peers.dat (03 23) written on flush with correct network IDs
- Addrv2 peers.dat reloads correctly (tested with 2059 addresses)
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
Documentation updates:
- doc/bips.md: Add BIP-155 to list of implemented BIPs for Zclassic v2.1.2
- doc/BIP-155-IMPLEMENTATION-PLAN.md:
- Document Bitcoin Core compatible peers.dat versioning scheme
- Add upgrade instructions with mandatory peers.dat backup step
- Document rollback procedures
- List critical bug fixes (nVersion read, m_net detection)
peers.dat format details:
- Legacy format: [magic][0x01][0x20]... (format=1, compat=32)
- BIP155 format: [magic][0x03][0x23]... (format=3, compat=35)
- Versioning uses INCOMPATIBILITY_BASE(32) + lowest_compatible
- Old nodes reject new format gracefully ("Corrupt peers.dat")
- New nodes can read both legacy and addrv2 formats
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
- Mark implementation as tested on macOS ARM64 only - Add TODO items for Linux and Windows testing - Add requirement for extended testnet validation before mainnet release - Document additional test results (peers.dat migration cycle) 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
- Remove pchOnionCat constant and all OnionCat IPv6 prefix handling - Remove v2 .onion (16-char) address parsing in SetSpecial() - Remove v2 ToStringIP() encoding - Unify IsTor() to just call IsTorV3() - Remove NET_ONION enum, add compatibility alias to NET_TORV3 - Remove ADDR_TORV2_SIZE constant - Update BIP155 handling to reject TORV2 addresses - Update tests to use v3 onion addresses instead of OnionCat Tor v2 has been deprecated since October 2021 and fully removed from the Tor network. This cleanup removes ~30 lines of dead code and simplifies the codebase for easier maintenance. 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
- Remove #define NET_ONION NET_TORV3 compatibility alias - Replace all NET_ONION references with NET_TORV3 in: - src/netbase.h (serialization) - src/netbase.cpp (ParseNetwork, GetNetwork, GetGroup) - src/init.cpp (proxy setup - cleaned up duplicate calls) - src/torcontrol.cpp (Tor authentication) - src/test/netbase_tests.cpp (v3 onion tests) - Update BIP-155 documentation to v3.0 - Regenerate cleanup diagram with better layout 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
- Shows NET_ONION completely removed (not just aliased) - Includes verification: grep NET_ONION = 0 results - Documents all files modified with NET_TORV3 references 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>
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Summary
NET_TORV3only (no aliases)Changes
BIP-155 Implementation
sendaddrv2message exchange during version handshakeOnion v2 Removal (Complete)
pchOnionCat[]constant (FD87:D87E:EB43 prefix)SetSpecial()ToStringIP()#define NET_ONION NET_TORV3aliasIsTor()to callIsTorV3()Files Modified
src/netbase.hsrc/netbase.cppsrc/init.cppsrc/torcontrol.cppsrc/net.h/src/net.cppsrc/addrman.h/src/addrman.cppsrc/test/netbase_tests.cppdoc/BIP-155-IMPLEMENTATION-PLAN.mdVerification
Test plan
grep NET_ONIONreturns 0 results (clean codebase)🤖 Generated with Claude Code