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Codecov Report❌ Patch coverage is
Additional details and impacted files@@ Coverage Diff @@
## main #3064 +/- ##
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+ Coverage 78.37% 78.53% +0.16%
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Files 689 689
Lines 121148 121175 +27
Branches 16973 16982 +9
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+ Hits 94948 95169 +221
+ Misses 25302 25106 -196
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justsmth
previously approved these changes
Mar 3, 2026
WillChilds-Klein
approved these changes
Mar 3, 2026
justsmth
approved these changes
Mar 3, 2026
WillChilds-Klein
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Mar 11, 2026
### Issues: Resolves: 17, 56, 58, 60 ### Description of changes: This PR rejects XOF digests in HKDF, cleanse sensitive states, and update function pointers: * HKDF is built on HMAC, which does not support XOF (extendable-output) algorithms such as SHAKE128 and SHAKE256. Previously, passing a SHAKE digest would fall through to HMAC, which rejects it internally - except in HKDF_expand, where EVP_MD_size() returns 0 for XOF digests, causing a division by zero before HMAC is ever called. * Add early EVP_MD_FLAG_XOF checks to all three public HKDF functions so that XOF digests are rejected immediately with a clear error rather than causing undefined behavior or relying on HMAC's internal rejection. * Cleanse bitstates in batched SHAKE operations. * Clean up digest context on early return in EVP_Digest. * Explicitly set XOF function pointers to NULL for EVP_sha512_224. ### Call-out: * Some check are _redundant_ - HKDF calls with SHAKE will fail once HMAC-layer is reached. However, this _redundancy_ aims at early failing in the expected API layer, thus prevents hidden bugs as the division by zero. ### Testing: `./crypto/crypto_test` By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license and the ISC license. --------- Co-authored-by: Justin W Smith <103147162+justsmth@users.noreply.github.com>
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Issues:
Resolves: 17, 56, 58, 60
Description of changes:
This PR rejects XOF digests in HKDF, cleanse sensitive states, and update function pointers:
Call-out:
Testing:
./crypto/crypto_testBy submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license and the ISC license.