From 950a81224e8bda92813c5ecf851f488c94f06aba Mon Sep 17 00:00:00 2001 From: Eric Biggers Date: Wed, 9 Jul 2025 13:01:09 -0700 Subject: lib/crypto: tests: Add hash-test-template.h and gen-hash-testvecs.py Add hash-test-template.h which generates the following KUnit test cases for hash functions: test_hash_test_vectors test_hash_all_lens_up_to_4096 test_hash_incremental_updates test_hash_buffer_overruns test_hash_overlaps test_hash_alignment_consistency test_hash_ctx_zeroization test_hash_interrupt_context_1 test_hash_interrupt_context_2 test_hmac (when HMAC is supported) benchmark_hash (when CONFIG_CRYPTO_LIB_BENCHMARK=y) The initial use cases for this will be sha224_kunit, sha256_kunit, sha384_kunit, sha512_kunit, and poly1305_kunit. Add a Python script gen-hash-testvecs.py which generates the test vectors required by test_hash_test_vectors, test_hash_all_lens_up_to_4096, and test_hmac. Acked-by: Ard Biesheuvel Link: https://lore.kernel.org/r/20250709200112.258500-2-ebiggers@kernel.org Signed-off-by: Eric Biggers --- scripts/crypto/gen-hash-testvecs.py | 102 ++++++++++++++++++++++++++++++++++++ 1 file changed, 102 insertions(+) create mode 100755 scripts/crypto/gen-hash-testvecs.py (limited to 'scripts/crypto/gen-hash-testvecs.py') diff --git a/scripts/crypto/gen-hash-testvecs.py b/scripts/crypto/gen-hash-testvecs.py new file mode 100755 index 000000000000..55f1010339a6 --- /dev/null +++ b/scripts/crypto/gen-hash-testvecs.py @@ -0,0 +1,102 @@ +#!/usr/bin/env python3 +# SPDX-License-Identifier: GPL-2.0-or-later +# +# Script that generates test vectors for the given cryptographic hash function. +# +# Copyright 2025 Google LLC + +import hashlib +import hmac +import sys + +DATA_LENS = [0, 1, 2, 3, 16, 32, 48, 49, 63, 64, 65, 127, 128, 129, 256, 511, + 513, 1000, 3333, 4096, 4128, 4160, 4224, 16384] + +# Generate the given number of random bytes, using the length itself as the seed +# for a simple linear congruential generator (LCG). The C test code uses the +# same LCG with the same seeding strategy to reconstruct the data, ensuring +# reproducibility without explicitly storing the data in the test vectors. +def rand_bytes(length): + seed = length + out = [] + for _ in range(length): + seed = (seed * 25214903917 + 11) % 2**48 + out.append((seed >> 16) % 256) + return bytes(out) + +def hash_init(alg): + return hashlib.new(alg) + +def hash_update(ctx, data): + ctx.update(data) + +def hash_final(ctx): + return ctx.digest() + +def compute_hash(alg, data): + ctx = hash_init(alg) + hash_update(ctx, data) + return hash_final(ctx) + +def print_bytes(prefix, value, bytes_per_line): + for i in range(0, len(value), bytes_per_line): + line = prefix + ''.join(f'0x{b:02x}, ' for b in value[i:i+bytes_per_line]) + print(f'{line.rstrip()}') + +def print_static_u8_array_definition(name, value): + print('') + print(f'static const u8 {name} = {{') + print_bytes('\t', value, 8) + print('};') + +def print_c_struct_u8_array_field(name, value): + print(f'\t\t.{name} = {{') + print_bytes('\t\t\t', value, 8) + print('\t\t},') + +def gen_unkeyed_testvecs(alg): + print('') + print('static const struct {') + print('\tsize_t data_len;') + print(f'\tu8 digest[{alg.upper()}_DIGEST_SIZE];') + print('} hash_testvecs[] = {') + for data_len in DATA_LENS: + data = rand_bytes(data_len) + print('\t{') + print(f'\t\t.data_len = {data_len},') + print_c_struct_u8_array_field('digest', compute_hash(alg, data)) + print('\t},') + print('};') + + data = rand_bytes(4096) + ctx = hash_init(alg) + for data_len in range(len(data) + 1): + hash_update(ctx, compute_hash(alg, data[:data_len])) + print_static_u8_array_definition( + f'hash_testvec_consolidated[{alg.upper()}_DIGEST_SIZE]', + hash_final(ctx)) + +def gen_hmac_testvecs(alg): + ctx = hmac.new(rand_bytes(32), digestmod=alg) + data = rand_bytes(4096) + for data_len in range(len(data) + 1): + ctx.update(data[:data_len]) + key_len = data_len % 293 + key = rand_bytes(key_len) + mac = hmac.digest(key, data[:data_len], alg) + ctx.update(mac) + print_static_u8_array_definition( + f'hmac_testvec_consolidated[{alg.upper()}_DIGEST_SIZE]', + ctx.digest()) + +if len(sys.argv) != 2: + sys.stderr.write('Usage: gen-hash-testvecs.py ALGORITHM\n') + sys.stderr.write('ALGORITHM may be any supported by Python hashlib.\n') + sys.stderr.write('Example: gen-hash-testvecs.py sha512\n') + sys.exit(1) + +alg = sys.argv[1] +print('/* SPDX-License-Identifier: GPL-2.0-or-later */') +print(f'/* This file was generated by: {sys.argv[0]} {" ".join(sys.argv[1:])} */') +gen_unkeyed_testvecs(alg) +gen_hmac_testvecs(alg) -- cgit v1.2.3