Add buffer size and callback checks to wc_LmsKey_Sign

[holtrop-wolfssl]

Description

Add buffer size and callback checks to wc_LmsKey_Sign

Fixes ZD#21439

Testing

Added unit tests to reproduce ZD bug report. Tested with and without fix in place.

Checklist

• added tests
• updated/added doxygen
• updated appropriate READMEs
• Updated manual and documentation

[Copilot]

Pull request overview

Adds stricter input validation to wc_LmsKey_Sign to prevent signing when the output buffer is too small or when required callbacks/context are missing, along with unit tests reproducing the reported issue (ZD#21439).

Changes:

• Add signature buffer size validation in wc_LmsKey_Sign.
• Require read/write private-key callbacks and context to be configured before signing.
• Add unit tests covering the new validation failures.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 3 comments.

File	Description
wolfcrypt/src/wc_lms.c	Adds early validation for signature buffer size, callbacks, and context in wc_LmsKey_Sign.
wolfcrypt/test/test.c	Adds unit tests to ensure wc_LmsKey_Sign returns expected errors for invalid inputs.

Comments suppressed due to low confidence (4)

wolfcrypt/test/test.c:1

• These casts convert msg to a non-const byte*, which discards constness even though wc_LmsKey_Sign takes a const byte* message pointer. Prefer passing msg without a cast (or casting to const byte* if needed) to avoid hiding accidental mutation and to keep const-correctness in the test.
  wolfcrypt/test/test.c:1
• These casts convert msg to a non-const byte*, which discards constness even though wc_LmsKey_Sign takes a const byte* message pointer. Prefer passing msg without a cast (or casting to const byte* if needed) to avoid hiding accidental mutation and to keep const-correctness in the test.
  wolfcrypt/test/test.c:1
• These casts convert msg to a non-const byte*, which discards constness even though wc_LmsKey_Sign takes a const byte* message pointer. Prefer passing msg without a cast (or casting to const byte* if needed) to avoid hiding accidental mutation and to keep const-correctness in the test.
  wolfcrypt/test/test.c:1
• These casts convert msg to a non-const byte*, which discards constness even though wc_LmsKey_Sign takes a const byte* message pointer. Prefer passing msg without a cast (or casting to const byte* if needed) to avoid hiding accidental mutation and to keep const-correctness in the test.

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[Copilot]

Pull request overview

Copilot reviewed 2 out of 2 changed files in this pull request and generated 3 comments.

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[Copilot]

Pull request overview

Copilot reviewed 2 out of 2 changed files in this pull request and generated no new comments.

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