XMSS: Fix index copy for signing.#9978
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JacobBarthelmeh merged 1 commit intowolfSSL:masterfrom Mar 16, 2026
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The index is already big-endian encoded but it needs to be front padded with zeros instead of back end padded.
JacobBarthelmeh
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Mar 16, 2026
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Pull request overview
Fixes XMSS index padding for signing by right-aligning the big-endian index within the destination buffer (zero-padding the front), addressing #9966.
Changes:
- Update
wc_idx_copy()to zero-pad the left side and copy the index into the end of the destination buffer. - Adjust the function comment to reflect the new alignment behavior.
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Description
The index is already big-endian encoded but it needs to be front padded with zeros instead of back end padded.
Fixes #9966
Testing
Standard XMSS build.