Skip to content
MoreBC2

Raw transaction RPC

CategoryDocumentationStatusSource-reviewed / Runtime-tested partialLast reviewed2026-09-12

Summary

Section titled “Summary”

This page covers node-level raw transaction and PSBT RPC behavior centered on src/rpc/rawtransaction.cpp.

The command inventory remains broadly Bitcoin-style, but BitcoinII Core v31.1.0 adds a material signing rule: transaction signing/finalization paths derive the replay-protection signature-hash domain for the next block.

Command surface

Section titled “Command surface”

Reviewed commands include:

  • getrawtransaction
  • createrawtransaction
  • decoderawtransaction
  • decodescript
  • combinerawtransaction
  • signrawtransactionwithkey
  • decodepsbt
  • combinepsbt
  • finalizepsbt
  • createpsbt
  • converttopsbt
  • utxoupdatepsbt
  • descriptorprocesspsbt
  • joinpsbts
  • analyzepsbt

Read-only lookup/decoding behavior remains structurally consistent with the earlier MoreBC2 review.

v31 next-block sighash domain

Section titled “v31 next-block sighash domain”

src/rpc/rawtransaction.cpp defines a next-block fork-id helper that derives:

SighashForkId(active_height + 1)

That matters at the activation boundary: a transaction intended for block 57750 must use the post-activation BC2 domain even when the current tip is still one block below activation.

Mainnet uses fork/domain id 0x01324342 from height 57750.

The domain propagates through relevant raw-transaction signing and PSBT precompute/finalization/analysis paths. A third-party service can therefore understand Bitcoin transaction/PSBT serialization while still being signing-incompatible with post-activation BitcoinII.

Read-only versus signing-sensitive behavior

Section titled “Read-only versus signing-sensitive behavior”

Replay protection does not make ordinary decoding or lookup inherently signing-sensitive. The material compatibility boundary is in workflows that create or verify signatures, finalize/extract signed PSBTs, or analyze signing completeness using BC2 signature semantics.

Runtime evidence — 2026-09-11

Section titled “Runtime evidence — 2026-09-11”

MoreBC2’s isolated v31 regtest PSBT test directly exercised raw/PSBT helpers including:

  • decodepsbt;
  • finalizepsbt;
  • decoderawtransaction;
  • testmempoolaccept;
  • local-only sendrawtransaction.

The PSBT was created and signed by a fresh disposable BitcoinII Core wallet, finalized successfully, decoded successfully, accepted by testmempoolaccept, and submitted only to a zero-peer local regtest mempool.

This establishes a working ordinary v31 raw-transaction/PSBT extraction and local-acceptance path under the documented environment. It is not a public broadcast test and does not runtime-exercise mainnet replay activation.

See Windows v31.1.0 PSBT and replay-protection validation — 2026-09-11.

Remaining verification work

Section titled “Remaining verification work”
  • deterministic pre/post-fork signature vectors;
  • explicit-key raw signing across the replay boundary;
  • raw-RPC versus wallet-signing digest equivalence tests;
  • third-party raw transaction/PSBT library compatibility;
  • public-network valid transaction broadcast.

Service guidance

Section titled “Service guidance”

Do not infer signing compatibility from address/script/PSBT format compatibility alone. Services that sign withdrawals should use current BitcoinII Core signing paths or independently implement and test the BC2 replay-domain rules.

Section titled “Related pages”

Sources

Section titled “Sources”

Pinned BitcoinII Core v31.1.0 paths include src/rpc/rawtransaction.cpp, src/rpc/rawtransaction_util.cpp, src/psbt.cpp, src/node/psbt.cpp, src/script/sign.cpp, and src/script/interpreter.cpp.

Canonical tag: https://github.com/Bitcoin-II/BitcoinII-Core/tree/v31.1.0

Verification

Section titled “Verification”

Status: Source-reviewed / Runtime-tested partial
Primary sources checked: BitcoinII Core v31.1.0 plus the 2026-09-11 isolated PSBT/raw-transaction runtime record
Notes: Next-block replay-domain propagation is source-backed. Ordinary PSBT finalization/decoding/local acceptance was runtime-tested; activation-boundary signing, third-party signing, and public broadcast remain open.