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Root cause of the never-passing 'HQC PQClean cgo e2e (NIST KAT roundtrip)' job, in two layers: 1. The lux-build runner had no C compiler (gcc/cc/clang absent), so cgo aborted before any code ran. Fixed in prior commits by installing build-essential + selecting an available CC. 2. With a compiler present, the cgo build then failed on accel@v1.1.9/ops/code/code_cpu.go's '#include "lux/gpu/hqc.h"' and '-lluxgpu_hqc' — the native HQC library (built from luxfi/mlx) that is NOT present in CI (nor in most consumers). accel v1.1.9 gated that native path on '//go:build cgo', so every cgo build hard-required the native lib/header. Fix: bump github.com/luxfi/accel v1.1.9 -> v1.2.4, which gates the native path behind '-tags=lux_hqc_native' and otherwise returns code.ErrNativeHQCUnavailable (documented: 'callers should fall back to their own CPU KEM path'). crypto/hqc now honours that contract: - gpu.go: batchEncapsulateGPU/batchDecapsulateGPU treat ErrNativeHQCUnavailable as 'declined' (return false,nil) so callers fall back to the per-item PQClean path. Secret buffers are zeroised on the decline path. - gpu_cgo.go: GF2Polymul falls back to the pure-Go Karatsuba path on ErrNativeHQCUnavailable. Removed the duplicated vecNSize64 / redMaskForMode / GF2Add (now shared). - gpu_polymul_purego.go (new, tag-neutral): the canonical pure-Go, PQClean-byte-identical GF(2)^N polymul (Karatsuba + reduce + base_mul), extracted from gpu_nocgo.go so BOTH builds share one implementation. - gpu_nocgo.go: trimmed to the thin !cgo public wrappers over the shared helpers. - randombytes_shim.c: split. Default (hqc_pqclean, no native) forwards randombytes -> hqcGoRandombytes only; the native seed-buffer dispatch (which references lux_hqc_randombytes / lux_hqc_seed_has_bytes from the native lib) moves to randombytes_shim_native.c, gated on lux_hqc_native. Previously the default build referenced those native-only symbols unconditionally, which would not link without the native lib. NOT a crypto/KAT regression: the NIST KAT roundtrip (TestKAT_HQC128/192/ 256), TestRoundTrip_AllModes, TestDeterminism, and the GF2 polymul known-answer vectors all pass byte-for-byte. The GPU batch tests skip gracefully when the native kernel is absent (their existing t.Skip path). Verified: CGO_ENABLED=1 go test -tags=hqc_pqclean ./hqc/ passes from a clean cache; cgo (with/without hqc_pqclean) and nocgo builds all green; broader suite unchanged (only pre-existing pkg-config failures in cgo/ and hash/poseidon2 remain, unrelated). Co-authored-by: Hanzo Dev <dev@hanzo.ai>
34 lines
1.4 KiB
C
34 lines
1.4 KiB
C
//go:build hqc_pqclean && !lux_hqc_native
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/*
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* randombytes_shim.c — PQClean randombytes() bridge (non-native build).
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*
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* PQClean's HQC reference calls `randombytes(out, n)` for every byte
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* of entropy it needs. In the default (non-native) build there is no
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* luxgpu_hqc static library linked in, so the only entropy source is
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* the Go-side io.Reader, reached via the cgo-exported hqcGoRandombytes
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* callback (backend_pqclean.go's installRNG + lock).
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*
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* The native batch path (C++ host kernel installing a per-slot TLS
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* seed buffer, served by lux_hqc_randombytes) is compiled only under
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* the `lux_hqc_native` build tag — see randombytes_shim_native.c.
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* Referencing those symbols here would leave them undefined at link
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* time whenever the native library is absent (which is the common
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* case: CI, pure-Go deployments). So this default TU forwards
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* unconditionally to Go.
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*
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* Determinism contract: every call consumes exactly `n` bytes from
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* the Go reader, in call order. Two KeyGen/Encapsulate invocations
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* seeded from byte-identical streams produce byte-identical outputs.
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* This is load-bearing for the HQC precompile.
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*/
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#include <stdint.h>
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#include <stddef.h>
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/* Forward declaration of the cgo-exported Go callback. */
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extern int hqcGoRandombytes(uint8_t *buf, size_t n);
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int randombytes(uint8_t *output, size_t n) {
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return hqcGoRandombytes(output, n);
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}
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