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libngu PR #59 patch

libngu-pr-59-patch

https://github.com/switck/libngu/pull/59.patch

Organisation
switck
Evidence role
Repository patch
Published
not established
Source changes
0
Detected differences
0
Unreviewed
0
Copies held
1

Patch content for the open incident-response proposal. Kept separately from the conversation and review-state capture.

Every check is recorded, including checks that found no text change. A detected edit is therefore bounded between two checks. The publisher's exact save time is not observable from this record. Last checked 2 Aug 2026, 00:58 UTC.

  1. Earliest copy held Current
    seen 1 Aug 2026, 06:39 UTC · Captured here text sha256 ced1e8bf8109e44ea31d04bc 64,233 chars
    Extracted text as captured
    From 4c0ea35499ab72245b5c8d0252312c0baccfc668 Mon Sep 17 00:00:00 2001
    From: "Javier G. Montoya S" <[email protected]>
    Date: Fri, 31 Jul 2026 17:42:44 -0400
    Subject: [PATCH 1/5] add HMAC_DRBG (SP 800-90A 10.1.2, SHA-256), verified
     against NIST CAVP vectors
    Self-contained core for the RNG rework that follows: K/V state machine
    with instantiate, mixing reseed, and backtracking-resistant generate.
    No heap allocation and no failure paths -- HMAC is built directly on
    the SHA-256 backend the rest of libngu already uses (mbedtls or cifra,
    as in hash.c), because mbedtls' HMAC layer allocates and hardware SHA
    (MBEDTLS_SHA256_ALT) can fail at runtime; the latter is refused at
    compile time until a target proves its no-fail contract. Reseed
    interval and prediction resistance are deliberately omitted and
    documented: the consumer (random.c, next commits) mixes fresh entropy
    into every output instead. Secret-bearing temporaries are wiped via a
    volatile-store helper the optimizer cannot elide.
    Verified by a host-compiled harness (ngu_tests: make cavp, part of
    'make tests') against official NIST CAVP vectors -- 12 vectors plus 2
    derived partial-block KATs, run through BOTH SHA-256 backends. The
    vector extractor cross-checks every vector against an independent
    pure-python reference before emitting; vectors are checked in with
    provenance.
    ---
     .gitignore                             |   2 +
     ngu/hmac_drbg.c                        | 149 +++++++++++++++++++
     ngu/hmac_drbg.h                        |  31 ++++
     ngu/ngu_tests/Makefile                 |  24 ++-
     ngu/ngu_tests/gen_hmac_drbg_vectors.py | 196 +++++++++++++++++++++++++
     ngu/ngu_tests/hmac_drbg_cavp.c         |  46 ++++++
     ngu/ngu_tests/hmac_drbg_cavp_vectors.h |  71 +++++++++
     7 files changed, 518 insertions(+), 1 deletion(-)
     create mode 100644 ngu/hmac_drbg.c
     create mode 100644 ngu/hmac_drbg.h
     create mode 100644 ngu/ngu_tests/gen_hmac_drbg_vectors.py
     create mode 100644 ngu/ngu_tests/hmac_drbg_cavp.c
     create mode 100644 ngu/ngu_tests/hmac_drbg_cavp_vectors.h
    diff --git a/.gitignore b/.gitignore
    index 35465d8..5881e0d 100644
    --- a/.gitignore
    +++ b/.gitignore

    Excerpt only. The complete copy is held offline and backs quotations on this site. The original publication remains the canonical public source.

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