From: Eric Biggers Date: Thu, 19 Mar 2026 06:17:05 +0000 (-0700) Subject: lib/crypto: tests: Add KUnit tests for GHASH X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=75e34bef53251744d95fd242b0345122fa462c7b;p=thirdparty%2Fkernel%2Fstable.git lib/crypto: tests: Add KUnit tests for GHASH Add a KUnit test suite for the GHASH library functions. It closely mirrors the POLYVAL test suite. Acked-by: Ard Biesheuvel Link: https://lore.kernel.org/r/20260319061723.1140720-5-ebiggers@kernel.org Signed-off-by: Eric Biggers --- diff --git a/lib/crypto/.kunitconfig b/lib/crypto/.kunitconfig index 63a592731d1d..391836511c8b 100644 --- a/lib/crypto/.kunitconfig +++ b/lib/crypto/.kunitconfig @@ -6,6 +6,7 @@ CONFIG_CRYPTO_LIB_AES_CBC_MACS_KUNIT_TEST=y CONFIG_CRYPTO_LIB_BLAKE2B_KUNIT_TEST=y CONFIG_CRYPTO_LIB_BLAKE2S_KUNIT_TEST=y CONFIG_CRYPTO_LIB_CURVE25519_KUNIT_TEST=y +CONFIG_CRYPTO_LIB_GHASH_KUNIT_TEST=y CONFIG_CRYPTO_LIB_MD5_KUNIT_TEST=y CONFIG_CRYPTO_LIB_MLDSA_KUNIT_TEST=y CONFIG_CRYPTO_LIB_NH_KUNIT_TEST=y diff --git a/lib/crypto/tests/Kconfig b/lib/crypto/tests/Kconfig index aa627b6b9855..5b60d5c3644b 100644 --- a/lib/crypto/tests/Kconfig +++ b/lib/crypto/tests/Kconfig @@ -35,6 +35,14 @@ config CRYPTO_LIB_CURVE25519_KUNIT_TEST help KUnit tests for the Curve25519 Diffie-Hellman function. +config CRYPTO_LIB_GHASH_KUNIT_TEST + tristate "KUnit tests for GHASH" if !KUNIT_ALL_TESTS + depends on KUNIT && CRYPTO_LIB_GF128HASH + default KUNIT_ALL_TESTS + select CRYPTO_LIB_BENCHMARK_VISIBLE + help + KUnit tests for the GHASH library functions. + config CRYPTO_LIB_MD5_KUNIT_TEST tristate "KUnit tests for MD5" if !KUNIT_ALL_TESTS depends on KUNIT && CRYPTO_LIB_MD5 diff --git a/lib/crypto/tests/Makefile b/lib/crypto/tests/Makefile index f864e0ffbee4..751ae507fdd0 100644 --- a/lib/crypto/tests/Makefile +++ b/lib/crypto/tests/Makefile @@ -4,6 +4,7 @@ obj-$(CONFIG_CRYPTO_LIB_AES_CBC_MACS_KUNIT_TEST) += aes_cbc_macs_kunit.o obj-$(CONFIG_CRYPTO_LIB_BLAKE2B_KUNIT_TEST) += blake2b_kunit.o obj-$(CONFIG_CRYPTO_LIB_BLAKE2S_KUNIT_TEST) += blake2s_kunit.o obj-$(CONFIG_CRYPTO_LIB_CURVE25519_KUNIT_TEST) += curve25519_kunit.o +obj-$(CONFIG_CRYPTO_LIB_GHASH_KUNIT_TEST) += ghash_kunit.o obj-$(CONFIG_CRYPTO_LIB_MD5_KUNIT_TEST) += md5_kunit.o obj-$(CONFIG_CRYPTO_LIB_MLDSA_KUNIT_TEST) += mldsa_kunit.o obj-$(CONFIG_CRYPTO_LIB_NH_KUNIT_TEST) += nh_kunit.o diff --git a/lib/crypto/tests/ghash-testvecs.h b/lib/crypto/tests/ghash-testvecs.h new file mode 100644 index 000000000000..759eb4072336 --- /dev/null +++ b/lib/crypto/tests/ghash-testvecs.h @@ -0,0 +1,186 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* This file was generated by: ./scripts/crypto/gen-hash-testvecs.py ghash */ + +static const struct { + size_t data_len; + u8 digest[GHASH_DIGEST_SIZE]; +} hash_testvecs[] = { + { + .data_len = 0, + .digest = { + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + }, + }, + { + .data_len = 1, + .digest = { + 0x13, 0x91, 0xa1, 0x11, 0x08, 0xc3, 0x7e, 0xeb, + 0x21, 0x42, 0x4a, 0xd6, 0x45, 0x0f, 0x41, 0xa7, + }, + }, + { + .data_len = 2, + .digest = { + 0xde, 0x00, 0x63, 0x3f, 0x71, 0x0f, 0xc6, 0x29, + 0x53, 0x2e, 0x49, 0xd9, 0xc2, 0xb7, 0x73, 0xce, + }, + }, + { + .data_len = 3, + .digest = { + 0xcf, 0xc7, 0xa8, 0x20, 0x24, 0xe9, 0x7a, 0x6c, + 0x2c, 0x2a, 0x34, 0x70, 0x26, 0xba, 0xd5, 0x9a, + }, + }, + { + .data_len = 16, + .digest = { + 0xaa, 0xe0, 0xdc, 0x7f, 0xcf, 0x8b, 0xe6, 0x0c, + 0x2e, 0x93, 0x89, 0x7d, 0x68, 0x4e, 0xc2, 0x63, + }, + }, + { + .data_len = 32, + .digest = { + 0x4b, 0x8b, 0x93, 0x5c, 0x79, 0xad, 0x85, 0x08, + 0xd3, 0x8a, 0xcd, 0xdd, 0x4c, 0x6e, 0x0e, 0x6f, + }, + }, + { + .data_len = 48, + .digest = { + 0xfa, 0xa0, 0x25, 0xdd, 0x61, 0x9a, 0x52, 0x9a, + 0xea, 0xee, 0xc6, 0x62, 0xb2, 0xba, 0x11, 0x49, + }, + }, + { + .data_len = 49, + .digest = { + 0x23, 0xf1, 0x05, 0xeb, 0x30, 0x40, 0xb9, 0x1d, + 0xe6, 0x35, 0x51, 0x4e, 0x0f, 0xc0, 0x1b, 0x9e, + }, + }, + { + .data_len = 63, + .digest = { + 0x8d, 0xcf, 0xa0, 0xc8, 0x83, 0x21, 0x06, 0x81, + 0xc6, 0x36, 0xd5, 0x62, 0xbf, 0xa0, 0xcd, 0x9c, + }, + }, + { + .data_len = 64, + .digest = { + 0xe7, 0xca, 0xbe, 0xe7, 0x66, 0xc8, 0x85, 0xad, + 0xbc, 0xaf, 0x58, 0x21, 0xd7, 0x67, 0x82, 0x15, + }, + }, + { + .data_len = 65, + .digest = { + 0x9f, 0x48, 0x10, 0xd9, 0xa2, 0x6b, 0x9d, 0xe0, + 0xb1, 0x87, 0xe1, 0x39, 0xc3, 0xd7, 0xee, 0x09, + }, + }, + { + .data_len = 127, + .digest = { + 0xa4, 0x36, 0xb7, 0x82, 0xd2, 0x67, 0x7e, 0xaf, + 0x5d, 0xfd, 0x67, 0x9c, 0x1d, 0x9f, 0xe4, 0xf7, + }, + }, + { + .data_len = 128, + .digest = { + 0x57, 0xe7, 0x1d, 0x78, 0xf0, 0x8e, 0xc7, 0x0c, + 0x15, 0xee, 0x18, 0xc4, 0xd1, 0x75, 0x90, 0xaa, + }, + }, + { + .data_len = 129, + .digest = { + 0x9b, 0xad, 0x81, 0xa9, 0x22, 0xb2, 0x19, 0x53, + 0x60, 0x30, 0xe7, 0xa0, 0x4f, 0xd6, 0x72, 0x42, + }, + }, + { + .data_len = 256, + .digest = { + 0xf7, 0x33, 0x42, 0xbf, 0x58, 0xde, 0x88, 0x0f, + 0x8d, 0x3d, 0xa6, 0x11, 0x14, 0xc3, 0xf1, 0xdc, + }, + }, + { + .data_len = 511, + .digest = { + 0x59, 0xdc, 0xa9, 0xc0, 0x4e, 0xd6, 0x97, 0xb3, + 0x60, 0xaf, 0xa8, 0xa0, 0xea, 0x54, 0x8e, 0xc3, + }, + }, + { + .data_len = 513, + .digest = { + 0xa2, 0x23, 0x37, 0xcc, 0x97, 0xec, 0xea, 0xbe, + 0xd6, 0xc7, 0x13, 0xf7, 0x93, 0x73, 0xc0, 0x64, + }, + }, + { + .data_len = 1000, + .digest = { + 0x46, 0x8b, 0x43, 0x77, 0x9b, 0xc2, 0xfc, 0xa4, + 0x68, 0x6a, 0x6c, 0x07, 0xa4, 0x6f, 0x47, 0x65, + }, + }, + { + .data_len = 3333, + .digest = { + 0x69, 0x7f, 0x19, 0xc3, 0xb9, 0xa4, 0xff, 0x40, + 0xe3, 0x03, 0x71, 0xa3, 0x88, 0x8a, 0xf1, 0xbd, + }, + }, + { + .data_len = 4096, + .digest = { + 0x4d, 0x65, 0xe6, 0x9c, 0xeb, 0x6a, 0x46, 0x8d, + 0xe9, 0x32, 0x96, 0x72, 0xb3, 0x0d, 0x08, 0xa9, + }, + }, + { + .data_len = 4128, + .digest = { + 0xfc, 0xa1, 0x74, 0x46, 0x21, 0x64, 0xa7, 0x64, + 0xbe, 0x47, 0x03, 0x1e, 0x05, 0xf7, 0xd8, 0x37, + }, + }, + { + .data_len = 4160, + .digest = { + 0x70, 0x5b, 0xe9, 0x17, 0xab, 0xd5, 0xa2, 0xee, + 0xcb, 0x39, 0xa4, 0x81, 0x2f, 0x41, 0x70, 0xae, + }, + }, + { + .data_len = 4224, + .digest = { + 0x07, 0xbd, 0xb6, 0x52, 0xe2, 0x75, 0x2c, 0x33, + 0x6d, 0x1b, 0x63, 0x56, 0x58, 0xda, 0x98, 0x55, + }, + }, + { + .data_len = 16384, + .digest = { + 0x9c, 0xb5, 0xf4, 0x14, 0xe8, 0xa8, 0x4a, 0xde, + 0xee, 0x7b, 0xbb, 0xd6, 0x21, 0x6d, 0x6a, 0x69, + }, + }, +}; + +static const u8 hash_testvec_consolidated[GHASH_DIGEST_SIZE] = { + 0x08, 0xef, 0xf5, 0x27, 0xb1, 0xca, 0xd4, 0x1d, + 0xad, 0x38, 0x69, 0x88, 0x6b, 0x16, 0xdf, 0xa8, +}; + +static const u8 ghash_allones_hashofhashes[GHASH_DIGEST_SIZE] = { + 0xef, 0x85, 0x58, 0xf8, 0x54, 0x9c, 0x5e, 0x54, + 0xd9, 0xbe, 0x04, 0x1f, 0xff, 0xff, 0xff, 0xff, +}; diff --git a/lib/crypto/tests/ghash_kunit.c b/lib/crypto/tests/ghash_kunit.c new file mode 100644 index 000000000000..68b3837a3607 --- /dev/null +++ b/lib/crypto/tests/ghash_kunit.c @@ -0,0 +1,194 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright 2026 Google LLC + */ +#include +#include "ghash-testvecs.h" + +/* + * A fixed key used when presenting GHASH as an unkeyed hash function in order + * to reuse hash-test-template.h. At the beginning of the test suite, this is + * initialized to a key prepared from bytes generated from a fixed seed. + */ +static struct ghash_key test_key; + +static void ghash_init_withtestkey(struct ghash_ctx *ctx) +{ + ghash_init(ctx, &test_key); +} + +static void ghash_withtestkey(const u8 *data, size_t len, + u8 out[GHASH_BLOCK_SIZE]) +{ + ghash(&test_key, data, len, out); +} + +/* Generate the HASH_KUNIT_CASES using hash-test-template.h. */ +#define HASH ghash_withtestkey +#define HASH_CTX ghash_ctx +#define HASH_SIZE GHASH_BLOCK_SIZE +#define HASH_INIT ghash_init_withtestkey +#define HASH_UPDATE ghash_update +#define HASH_FINAL ghash_final +#include "hash-test-template.h" + +/* + * Test a key and messages containing all one bits. This is useful to detect + * overflow bugs in implementations that emulate carryless multiplication using + * a series of standard multiplications with the bits spread out. + */ +static void test_ghash_allones_key_and_message(struct kunit *test) +{ + struct ghash_key key; + struct ghash_ctx hashofhashes_ctx; + u8 hash[GHASH_BLOCK_SIZE]; + + static_assert(TEST_BUF_LEN >= 4096); + memset(test_buf, 0xff, 4096); + + ghash_preparekey(&key, test_buf); + ghash_init(&hashofhashes_ctx, &key); + for (size_t len = 0; len <= 4096; len += 16) { + ghash(&key, test_buf, len, hash); + ghash_update(&hashofhashes_ctx, hash, sizeof(hash)); + } + ghash_final(&hashofhashes_ctx, hash); + KUNIT_ASSERT_MEMEQ(test, hash, ghash_allones_hashofhashes, + sizeof(hash)); +} + +#define MAX_LEN_FOR_KEY_CHECK 1024 + +/* + * Given two prepared keys which should be identical (but may differ in + * alignment and/or whether they are followed by a guard page or not), verify + * that they produce consistent results on various data lengths. + */ +static void check_key_consistency(struct kunit *test, + const struct ghash_key *key1, + const struct ghash_key *key2) +{ + u8 *data = test_buf; + u8 hash1[GHASH_BLOCK_SIZE]; + u8 hash2[GHASH_BLOCK_SIZE]; + + rand_bytes(data, MAX_LEN_FOR_KEY_CHECK); + KUNIT_ASSERT_MEMEQ(test, key1, key2, sizeof(*key1)); + + for (int i = 0; i < 100; i++) { + size_t len = rand_length(MAX_LEN_FOR_KEY_CHECK); + + ghash(key1, data, len, hash1); + ghash(key2, data, len, hash2); + KUNIT_ASSERT_MEMEQ(test, hash1, hash2, sizeof(hash1)); + } +} + +/* Test that no buffer overreads occur on either raw_key or ghash_key. */ +static void test_ghash_with_guarded_key(struct kunit *test) +{ + u8 raw_key[GHASH_BLOCK_SIZE]; + u8 *guarded_raw_key = &test_buf[TEST_BUF_LEN - sizeof(raw_key)]; + struct ghash_key key1, key2; + struct ghash_key *guarded_key = + (struct ghash_key *)&test_buf[TEST_BUF_LEN - sizeof(key1)]; + + /* Prepare with regular buffers. */ + rand_bytes(raw_key, sizeof(raw_key)); + ghash_preparekey(&key1, raw_key); + + /* Prepare with guarded raw_key, then check that it works. */ + memcpy(guarded_raw_key, raw_key, sizeof(raw_key)); + ghash_preparekey(&key2, guarded_raw_key); + check_key_consistency(test, &key1, &key2); + + /* Prepare guarded ghash_key, then check that it works. */ + ghash_preparekey(guarded_key, raw_key); + check_key_consistency(test, &key1, guarded_key); +} + +/* + * Test that ghash_key only needs to be aligned to + * __alignof__(struct ghash_key), i.e. 8 bytes. The assembly code may prefer + * 16-byte or higher alignment, but it mustn't require it. + */ +static void test_ghash_with_minimally_aligned_key(struct kunit *test) +{ + u8 raw_key[GHASH_BLOCK_SIZE]; + struct ghash_key key; + struct ghash_key *minaligned_key = + (struct ghash_key *)&test_buf[MAX_LEN_FOR_KEY_CHECK + + __alignof__(struct ghash_key)]; + + KUNIT_ASSERT_TRUE(test, IS_ALIGNED((uintptr_t)minaligned_key, + __alignof__(struct ghash_key))); + KUNIT_ASSERT_TRUE(test, !IS_ALIGNED((uintptr_t)minaligned_key, + 2 * __alignof__(struct ghash_key))); + + rand_bytes(raw_key, sizeof(raw_key)); + ghash_preparekey(&key, raw_key); + ghash_preparekey(minaligned_key, raw_key); + check_key_consistency(test, &key, minaligned_key); +} + +struct ghash_irq_test_state { + struct ghash_key expected_key; + u8 raw_key[GHASH_BLOCK_SIZE]; +}; + +static bool ghash_irq_test_func(void *state_) +{ + struct ghash_irq_test_state *state = state_; + struct ghash_key key; + + ghash_preparekey(&key, state->raw_key); + return memcmp(&key, &state->expected_key, sizeof(key)) == 0; +} + +/* + * Test that ghash_preparekey() produces the same output regardless of whether + * FPU or vector registers are usable when it is called. + */ +static void test_ghash_preparekey_in_irqs(struct kunit *test) +{ + struct ghash_irq_test_state state; + + rand_bytes(state.raw_key, sizeof(state.raw_key)); + ghash_preparekey(&state.expected_key, state.raw_key); + kunit_run_irq_test(test, ghash_irq_test_func, 200000, &state); +} + +static int ghash_suite_init(struct kunit_suite *suite) +{ + u8 raw_key[GHASH_BLOCK_SIZE]; + + rand_bytes_seeded_from_len(raw_key, sizeof(raw_key)); + ghash_preparekey(&test_key, raw_key); + return hash_suite_init(suite); +} + +static void ghash_suite_exit(struct kunit_suite *suite) +{ + hash_suite_exit(suite); +} + +static struct kunit_case ghash_test_cases[] = { + HASH_KUNIT_CASES, + KUNIT_CASE(test_ghash_allones_key_and_message), + KUNIT_CASE(test_ghash_with_guarded_key), + KUNIT_CASE(test_ghash_with_minimally_aligned_key), + KUNIT_CASE(test_ghash_preparekey_in_irqs), + KUNIT_CASE(benchmark_hash), + {}, +}; + +static struct kunit_suite ghash_test_suite = { + .name = "ghash", + .test_cases = ghash_test_cases, + .suite_init = ghash_suite_init, + .suite_exit = ghash_suite_exit, +}; +kunit_test_suite(ghash_test_suite); + +MODULE_DESCRIPTION("KUnit tests and benchmark for GHASH"); +MODULE_LICENSE("GPL"); diff --git a/scripts/crypto/gen-hash-testvecs.py b/scripts/crypto/gen-hash-testvecs.py index 34b7c48f3456..e69ce213fb33 100755 --- a/scripts/crypto/gen-hash-testvecs.py +++ b/scripts/crypto/gen-hash-testvecs.py @@ -68,6 +68,52 @@ class Poly1305: m = (self.h + self.s) % 2**128 return m.to_bytes(16, byteorder='little') +GHASH_POLY = sum((1 << i) for i in [128, 7, 2, 1, 0]) +GHASH_BLOCK_SIZE = 16 + +# A straightforward, unoptimized implementation of GHASH. +class Ghash: + + @staticmethod + def reflect_bits_in_bytes(v): + res = 0 + for offs in range(0, 128, 8): + for bit in range(8): + if (v & (1 << (offs + bit))) != 0: + res ^= 1 << (offs + 7 - bit) + return res + + @staticmethod + def bytes_to_poly(data): + return Ghash.reflect_bits_in_bytes(int.from_bytes(data, byteorder='little')) + + @staticmethod + def poly_to_bytes(poly): + return Ghash.reflect_bits_in_bytes(poly).to_bytes(16, byteorder='little') + + def __init__(self, key): + assert len(key) == 16 + self.h = Ghash.bytes_to_poly(key) + self.acc = 0 + + # Note: this supports partial blocks only at the end. + def update(self, data): + for i in range(0, len(data), 16): + # acc += block + self.acc ^= Ghash.bytes_to_poly(data[i:i+16]) + # acc = (acc * h) mod GHASH_POLY + product = 0 + for j in range(127, -1, -1): + if (self.h & (1 << j)) != 0: + product ^= self.acc << j + if (product & (1 << (128 + j))) != 0: + product ^= GHASH_POLY << j + self.acc = product + return self + + def digest(self): + return Ghash.poly_to_bytes(self.acc) + POLYVAL_POLY = sum((1 << i) for i in [128, 127, 126, 121, 0]) POLYVAL_BLOCK_SIZE = 16 @@ -103,6 +149,8 @@ def hash_init(alg): # unkeyed hash functions to work on them. if alg == 'aes-cmac': return AesCmac(rand_bytes(AES_256_KEY_SIZE)) + if alg == 'ghash': + return Ghash(rand_bytes(GHASH_BLOCK_SIZE)) if alg == 'poly1305': return Poly1305(rand_bytes(POLY1305_KEY_SIZE)) if alg == 'polyval': @@ -257,6 +305,15 @@ def gen_additional_poly1305_testvecs(): 'poly1305_allones_macofmacs[POLY1305_DIGEST_SIZE]', Poly1305(key).update(data).digest()) +def gen_additional_ghash_testvecs(): + key = b'\xff' * GHASH_BLOCK_SIZE + hashes = b'' + for data_len in range(0, 4097, 16): + hashes += Ghash(key).update(b'\xff' * data_len).digest() + print_static_u8_array_definition( + 'ghash_allones_hashofhashes[GHASH_DIGEST_SIZE]', + Ghash(key).update(hashes).digest()) + def gen_additional_polyval_testvecs(): key = b'\xff' * POLYVAL_BLOCK_SIZE hashes = b'' @@ -268,7 +325,8 @@ def gen_additional_polyval_testvecs(): 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; or poly1305, polyval, or sha3.\n') + sys.stderr.write('ALGORITHM may be any supported by Python hashlib;\n') + sys.stderr.write(' or aes-cmac, ghash, nh, poly1305, polyval, or sha3.\n') sys.stderr.write('Example: gen-hash-testvecs.py sha512\n') sys.exit(1) @@ -280,6 +338,9 @@ if alg == 'aes-cmac': elif alg.startswith('blake2'): gen_unkeyed_testvecs(alg) gen_additional_blake2_testvecs(alg) +elif alg == 'ghash': + gen_unkeyed_testvecs(alg) + gen_additional_ghash_testvecs() elif alg == 'nh': gen_nh_testvecs() elif alg == 'poly1305':