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  • src/ssh/kex/libcrux_mlkem

    From Deuc¿@VERT to Git commit to main/sbbs/m on Thursday, March 26, 2026 03:45:00
    https://gitlab.synchro.net/main/sbbs/-/commit/2eea8a78fa3f28b81c861559
    Added Files:
    src/ssh/kex/libcrux_mlkem768_sha3.h mlkem768.c mlkem768.h mlkem768x25519-sha256.c
    Modified Files:
    src/ssh/CMakeLists.txt client.c deucessh-algorithms.h src/ssh/test/CMakeLists.txt test_alloc.c test_auth.c test_conn.c test_dhgex_provider.h test_selftest.c test_transport.c
    Log Message:
    Implement mlkem768x25519-sha256 post-quantum hybrid KEX

    Adds mlkem768x25519-sha256 key exchange combining ML-KEM-768
    (FIPS 203) with X25519, hashed with SHA-256. Supported in OpenSSH
    since 9.9; verified interop against OpenSSH 9.9.

    New files:
    - kex/libcrux_mlkem768_sha3.h: ML-KEM-768 implementation from
    libcrux (Cryspen, MIT license). Self-contained with its own
    SHA-3/SHAKE. 23 -Wconversion casts fixed, stdbool.h added,
    KRML_HOST_EXIT changed from fatal_f to abort.
    - kex/mlkem768.h, kex/mlkem768.c: thin wrappers providing a
    byte-array API with RAND_bytes for randomness. Public key
    validation via libcrux validate_public_key. Error propagation
    on RAND_bytes failure.
    - kex/mlkem768x25519-sha256.c: KEX handler module following the
    sntrup761x25519-sha512 pattern. SHA-256 hash, string-encoded K.

    Test matrix expanded from 6 to 8 variants (mlkem, mlkem_rsa).
    4277 tests passing.

    Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

    ---
    þ Synchronet þ Vertrauen þ Home of Synchronet þ [vert/cvs/bbs].synchro.net
  • From Deuc¿@VERT to Git commit to main/sbbs/m on Friday, March 27, 2026 20:57:00
    https://gitlab.synchro.net/main/sbbs/-/commit/26addde18e25b790b1778e71
    Modified Files:
    src/ssh/kex/libcrux_mlkem768_sha3.h sntrup761.c src/ssh/ssh-arch.c src/ssh/test/dssh_test_ossl.c test_alloc.c test_transport.c
    Log Message:
    Fix all GCC13 -Wconversion/-Wpedantic warnings for clean -Werror builds

    Add explicit narrowing casts throughout sntrup761.c (popcount helpers,
    XOR-swap loops, field element arithmetic), libcrux_mlkem768_sha3.h
    (Barrett reduction), ssh-arch.c and test helpers (serialize shifts).
    Fix missing openssl/rsa.h include for EVP_PKEY_CTX_set_rsa_padding
    declaration. Replace ISO C-forbidden object-to-function-pointer casts
    in tests with memcpy. Both GCC13 and Clang now build clean with
    -Werror -Wconversion; 4487/4487 tests pass on both compilers.

    Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

    ---
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