small ecc signatures have bad padding#86
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lealem47 merged 1 commit intowolfSSL:masterfrom Mar 9, 2026
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Thanks @sebastian-carpenter !
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ecc signatures were pretty much guaranteed to fail every few hundred iterations.
When the signature is generated
mp_to_unsigned_binwas used to write it out but this function does not pad the buffer. As a result, smaller signatures would leave 0x00 bytes at the end. The buffer is a big-endian number so it would later be interpreted incorrectly.Replaced
mp_to_unsigned_binwithmp_to_unsigned_bin_lenas is normally done in the wolfcrypt ecc code. This will left-pad the buffer.