feat(wasm-utxo): fix zcash blake2b sighash for 256-byte outputs#257
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feat(wasm-utxo): fix zcash blake2b sighash for 256-byte outputs#257
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A Zcash transaction with 8 P2SH outputs has a 256-byte outputs preimage (8 × 32 bytes each), which is an exact multiple of the 128-byte BLAKE2b block size. The old blake2b_256_personal in rust-bitcoin processed all complete blocks eagerly and left an empty buffer for finalize, causing a spurious all-zero final block and an incorrect sighash. This test signs such a transaction and verifies the signature, catching the regression in wasm-utxo's Zcash signing and verification path. Issue: BTC-0
Update miniscript dependency from bitgo.1 to bitgo.2, which includes the corresponding bitcoin crate update to 0.32.8-bitgo.2. Issue: BTC-0 Co-authored-by: llm-git <llm-git@ttll.de>
lcovar
approved these changes
Apr 22, 2026
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Update miniscript dependency from bitgo.1 to bitgo.2, which includes
the corresponding bitcoin crate update to 0.32.8-bitgo.2.
A Zcash transaction with 8 P2SH outputs has a 256-byte outputs preimage
(8 × 32 bytes each), which is an exact multiple of the 128-byte BLAKE2b
block size. The old blake2b_256_personal in rust-bitcoin processed all
complete blocks eagerly and left an empty buffer for finalize, causing a
spurious all-zero final block and an incorrect sighash.
Added regression test that signs such a transaction and verifies the
signature, catching the regression in wasm-utxo's Zcash signing and
verification path.
Issue: BTC-0