BitGo / rust-bitcoin

82%

master: 83%

push

github

fix(crypto): fix BLAKE2b finalization for block-aligned inputs in ZIP-243

The blake2b_256_personal function had a manual loop that processed all
complete 128-byte blocks with the finalization flag f=0. For inputs whose
length is an exact multiple of the block size (e.g. the outputs preimage
for 8+ outputs), the finalize call would find an empty buffer and compress
a spurious all-zero block as the final block, producing the wrong hash.

Fix: remove the manual loop and feed all data through the Lazy buffer
(buffer.digest_blocks), which retains the last block until finalize so
the correct finalization flag is always applied.

1 of 1 new or added line in 1 file covered. (100.0%)

17138 of 20776 relevant lines covered (82.49%)

17336.58 hits per line