crypto: md5 - Wrap library and add HMAC support

Reimplement crypto/md5.c on top of the new MD5 library functions.  Also
add support for HMAC-MD5, again just wrapping the library functions.

This closely mirrors crypto/sha1.c.

Link: https://lore.kernel.org/r/20250805222855.10362-7-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@kernel.org>
This commit is contained in:
Eric Biggers 2025-08-05 15:28:54 -07:00
parent a1848f6e38
commit ba8ee22a7f
4 changed files with 171 additions and 194 deletions

View file

@ -938,8 +938,9 @@ config CRYPTO_MD4
config CRYPTO_MD5
tristate "MD5"
select CRYPTO_HASH
select CRYPTO_LIB_MD5
help
MD5 message digest algorithm (RFC1321)
MD5 message digest algorithm (RFC1321), including HMAC support.
config CRYPTO_MICHAEL_MIC
tristate "Michael MIC"

View file

@ -1,25 +1,50 @@
/*
* Cryptographic API.
*
* MD5 Message Digest Algorithm (RFC1321).
*
* Derived from cryptoapi implementation, originally based on the
* public domain implementation written by Colin Plumb in 1993.
*
* Copyright (c) Cryptoapi developers.
* Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the Free
* Software Foundation; either version 2 of the License, or (at your option)
* any later version.
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Crypto API support for MD5 and HMAC-MD5
*
* Copyright 2025 Google LLC
*/
#include <crypto/internal/hash.h>
#include <crypto/md5.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/string.h>
/*
* Export and import functions. crypto_shash wants a particular format that
* matches that used by some legacy drivers. It currently is the same as the
* library MD5 context, except the value in bytecount must be block-aligned and
* the remainder must be stored in an extra u8 appended to the struct.
*/
#define MD5_SHASH_STATE_SIZE (sizeof(struct md5_ctx) + 1)
static_assert(sizeof(struct md5_ctx) == sizeof(struct md5_state));
static_assert(offsetof(struct md5_ctx, state) == offsetof(struct md5_state, hash));
static_assert(offsetof(struct md5_ctx, bytecount) == offsetof(struct md5_state, byte_count));
static_assert(offsetof(struct md5_ctx, buf) == offsetof(struct md5_state, block));
static int __crypto_md5_export(const struct md5_ctx *ctx0, void *out)
{
struct md5_ctx ctx = *ctx0;
unsigned int partial;
u8 *p = out;
partial = ctx.bytecount % MD5_BLOCK_SIZE;
ctx.bytecount -= partial;
memcpy(p, &ctx, sizeof(ctx));
p += sizeof(ctx);
*p = partial;
return 0;
}
static int __crypto_md5_import(struct md5_ctx *ctx, const void *in)
{
const u8 *p = in;
memcpy(ctx, p, sizeof(*ctx));
p += sizeof(*ctx);
ctx->bytecount += *p;
return 0;
}
const u8 md5_zero_message_hash[MD5_DIGEST_SIZE] = {
0xd4, 0x1d, 0x8c, 0xd9, 0x8f, 0x00, 0xb2, 0x04,
@ -27,198 +52,146 @@ const u8 md5_zero_message_hash[MD5_DIGEST_SIZE] = {
};
EXPORT_SYMBOL_GPL(md5_zero_message_hash);
#define F1(x, y, z) (z ^ (x & (y ^ z)))
#define F2(x, y, z) F1(z, x, y)
#define F3(x, y, z) (x ^ y ^ z)
#define F4(x, y, z) (y ^ (x | ~z))
#define MD5_CTX(desc) ((struct md5_ctx *)shash_desc_ctx(desc))
#define MD5STEP(f, w, x, y, z, in, s) \
(w += f(x, y, z) + in, w = (w<<s | w>>(32-s)) + x)
static void md5_transform(__u32 *hash, __u32 const *in)
static int crypto_md5_init(struct shash_desc *desc)
{
u32 a, b, c, d;
a = hash[0];
b = hash[1];
c = hash[2];
d = hash[3];
MD5STEP(F1, a, b, c, d, in[0] + 0xd76aa478, 7);
MD5STEP(F1, d, a, b, c, in[1] + 0xe8c7b756, 12);
MD5STEP(F1, c, d, a, b, in[2] + 0x242070db, 17);
MD5STEP(F1, b, c, d, a, in[3] + 0xc1bdceee, 22);
MD5STEP(F1, a, b, c, d, in[4] + 0xf57c0faf, 7);
MD5STEP(F1, d, a, b, c, in[5] + 0x4787c62a, 12);
MD5STEP(F1, c, d, a, b, in[6] + 0xa8304613, 17);
MD5STEP(F1, b, c, d, a, in[7] + 0xfd469501, 22);
MD5STEP(F1, a, b, c, d, in[8] + 0x698098d8, 7);
MD5STEP(F1, d, a, b, c, in[9] + 0x8b44f7af, 12);
MD5STEP(F1, c, d, a, b, in[10] + 0xffff5bb1, 17);
MD5STEP(F1, b, c, d, a, in[11] + 0x895cd7be, 22);
MD5STEP(F1, a, b, c, d, in[12] + 0x6b901122, 7);
MD5STEP(F1, d, a, b, c, in[13] + 0xfd987193, 12);
MD5STEP(F1, c, d, a, b, in[14] + 0xa679438e, 17);
MD5STEP(F1, b, c, d, a, in[15] + 0x49b40821, 22);
MD5STEP(F2, a, b, c, d, in[1] + 0xf61e2562, 5);
MD5STEP(F2, d, a, b, c, in[6] + 0xc040b340, 9);
MD5STEP(F2, c, d, a, b, in[11] + 0x265e5a51, 14);
MD5STEP(F2, b, c, d, a, in[0] + 0xe9b6c7aa, 20);
MD5STEP(F2, a, b, c, d, in[5] + 0xd62f105d, 5);
MD5STEP(F2, d, a, b, c, in[10] + 0x02441453, 9);
MD5STEP(F2, c, d, a, b, in[15] + 0xd8a1e681, 14);
MD5STEP(F2, b, c, d, a, in[4] + 0xe7d3fbc8, 20);
MD5STEP(F2, a, b, c, d, in[9] + 0x21e1cde6, 5);
MD5STEP(F2, d, a, b, c, in[14] + 0xc33707d6, 9);
MD5STEP(F2, c, d, a, b, in[3] + 0xf4d50d87, 14);
MD5STEP(F2, b, c, d, a, in[8] + 0x455a14ed, 20);
MD5STEP(F2, a, b, c, d, in[13] + 0xa9e3e905, 5);
MD5STEP(F2, d, a, b, c, in[2] + 0xfcefa3f8, 9);
MD5STEP(F2, c, d, a, b, in[7] + 0x676f02d9, 14);
MD5STEP(F2, b, c, d, a, in[12] + 0x8d2a4c8a, 20);
MD5STEP(F3, a, b, c, d, in[5] + 0xfffa3942, 4);
MD5STEP(F3, d, a, b, c, in[8] + 0x8771f681, 11);
MD5STEP(F3, c, d, a, b, in[11] + 0x6d9d6122, 16);
MD5STEP(F3, b, c, d, a, in[14] + 0xfde5380c, 23);
MD5STEP(F3, a, b, c, d, in[1] + 0xa4beea44, 4);
MD5STEP(F3, d, a, b, c, in[4] + 0x4bdecfa9, 11);
MD5STEP(F3, c, d, a, b, in[7] + 0xf6bb4b60, 16);
MD5STEP(F3, b, c, d, a, in[10] + 0xbebfbc70, 23);
MD5STEP(F3, a, b, c, d, in[13] + 0x289b7ec6, 4);
MD5STEP(F3, d, a, b, c, in[0] + 0xeaa127fa, 11);
MD5STEP(F3, c, d, a, b, in[3] + 0xd4ef3085, 16);
MD5STEP(F3, b, c, d, a, in[6] + 0x04881d05, 23);
MD5STEP(F3, a, b, c, d, in[9] + 0xd9d4d039, 4);
MD5STEP(F3, d, a, b, c, in[12] + 0xe6db99e5, 11);
MD5STEP(F3, c, d, a, b, in[15] + 0x1fa27cf8, 16);
MD5STEP(F3, b, c, d, a, in[2] + 0xc4ac5665, 23);
MD5STEP(F4, a, b, c, d, in[0] + 0xf4292244, 6);
MD5STEP(F4, d, a, b, c, in[7] + 0x432aff97, 10);
MD5STEP(F4, c, d, a, b, in[14] + 0xab9423a7, 15);
MD5STEP(F4, b, c, d, a, in[5] + 0xfc93a039, 21);
MD5STEP(F4, a, b, c, d, in[12] + 0x655b59c3, 6);
MD5STEP(F4, d, a, b, c, in[3] + 0x8f0ccc92, 10);
MD5STEP(F4, c, d, a, b, in[10] + 0xffeff47d, 15);
MD5STEP(F4, b, c, d, a, in[1] + 0x85845dd1, 21);
MD5STEP(F4, a, b, c, d, in[8] + 0x6fa87e4f, 6);
MD5STEP(F4, d, a, b, c, in[15] + 0xfe2ce6e0, 10);
MD5STEP(F4, c, d, a, b, in[6] + 0xa3014314, 15);
MD5STEP(F4, b, c, d, a, in[13] + 0x4e0811a1, 21);
MD5STEP(F4, a, b, c, d, in[4] + 0xf7537e82, 6);
MD5STEP(F4, d, a, b, c, in[11] + 0xbd3af235, 10);
MD5STEP(F4, c, d, a, b, in[2] + 0x2ad7d2bb, 15);
MD5STEP(F4, b, c, d, a, in[9] + 0xeb86d391, 21);
hash[0] += a;
hash[1] += b;
hash[2] += c;
hash[3] += d;
}
static inline void md5_transform_helper(struct md5_state *ctx,
u32 block[MD5_BLOCK_WORDS])
{
le32_to_cpu_array(block, MD5_BLOCK_WORDS);
md5_transform(ctx->hash, block);
}
static int md5_init(struct shash_desc *desc)
{
struct md5_state *mctx = shash_desc_ctx(desc);
mctx->hash[0] = MD5_H0;
mctx->hash[1] = MD5_H1;
mctx->hash[2] = MD5_H2;
mctx->hash[3] = MD5_H3;
mctx->byte_count = 0;
md5_init(MD5_CTX(desc));
return 0;
}
static int md5_update(struct shash_desc *desc, const u8 *data, unsigned int len)
static int crypto_md5_update(struct shash_desc *desc,
const u8 *data, unsigned int len)
{
struct md5_state *mctx = shash_desc_ctx(desc);
u32 block[MD5_BLOCK_WORDS];
mctx->byte_count += len;
do {
memcpy(block, data, sizeof(block));
md5_transform_helper(mctx, block);
data += sizeof(block);
len -= sizeof(block);
} while (len >= sizeof(block));
memzero_explicit(block, sizeof(block));
mctx->byte_count -= len;
return len;
}
static int md5_finup(struct shash_desc *desc, const u8 *data, unsigned int len,
u8 *out)
{
struct md5_state *mctx = shash_desc_ctx(desc);
u32 block[MD5_BLOCK_WORDS];
unsigned int offset;
int padding;
char *p;
memcpy(block, data, len);
offset = len;
p = (char *)block + offset;
padding = 56 - (offset + 1);
*p++ = 0x80;
if (padding < 0) {
memset(p, 0x00, padding + sizeof (u64));
md5_transform_helper(mctx, block);
p = (char *)block;
padding = 56;
}
memset(p, 0, padding);
mctx->byte_count += len;
block[14] = mctx->byte_count << 3;
block[15] = mctx->byte_count >> 29;
le32_to_cpu_array(block, (sizeof(block) - sizeof(u64)) / sizeof(u32));
md5_transform(mctx->hash, block);
memzero_explicit(block, sizeof(block));
cpu_to_le32_array(mctx->hash, sizeof(mctx->hash) / sizeof(u32));
memcpy(out, mctx->hash, sizeof(mctx->hash));
md5_update(MD5_CTX(desc), data, len);
return 0;
}
static struct shash_alg alg = {
.digestsize = MD5_DIGEST_SIZE,
.init = md5_init,
.update = md5_update,
.finup = md5_finup,
.descsize = MD5_STATE_SIZE,
.base = {
.cra_name = "md5",
.cra_driver_name = "md5-generic",
.cra_flags = CRYPTO_AHASH_ALG_BLOCK_ONLY,
.cra_blocksize = MD5_HMAC_BLOCK_SIZE,
.cra_module = THIS_MODULE,
}
static int crypto_md5_final(struct shash_desc *desc, u8 *out)
{
md5_final(MD5_CTX(desc), out);
return 0;
}
static int crypto_md5_digest(struct shash_desc *desc,
const u8 *data, unsigned int len, u8 *out)
{
md5(data, len, out);
return 0;
}
static int crypto_md5_export(struct shash_desc *desc, void *out)
{
return __crypto_md5_export(MD5_CTX(desc), out);
}
static int crypto_md5_import(struct shash_desc *desc, const void *in)
{
return __crypto_md5_import(MD5_CTX(desc), in);
}
#define HMAC_MD5_KEY(tfm) ((struct hmac_md5_key *)crypto_shash_ctx(tfm))
#define HMAC_MD5_CTX(desc) ((struct hmac_md5_ctx *)shash_desc_ctx(desc))
static int crypto_hmac_md5_setkey(struct crypto_shash *tfm,
const u8 *raw_key, unsigned int keylen)
{
hmac_md5_preparekey(HMAC_MD5_KEY(tfm), raw_key, keylen);
return 0;
}
static int crypto_hmac_md5_init(struct shash_desc *desc)
{
hmac_md5_init(HMAC_MD5_CTX(desc), HMAC_MD5_KEY(desc->tfm));
return 0;
}
static int crypto_hmac_md5_update(struct shash_desc *desc,
const u8 *data, unsigned int len)
{
hmac_md5_update(HMAC_MD5_CTX(desc), data, len);
return 0;
}
static int crypto_hmac_md5_final(struct shash_desc *desc, u8 *out)
{
hmac_md5_final(HMAC_MD5_CTX(desc), out);
return 0;
}
static int crypto_hmac_md5_digest(struct shash_desc *desc,
const u8 *data, unsigned int len, u8 *out)
{
hmac_md5(HMAC_MD5_KEY(desc->tfm), data, len, out);
return 0;
}
static int crypto_hmac_md5_export(struct shash_desc *desc, void *out)
{
return __crypto_md5_export(&HMAC_MD5_CTX(desc)->hash_ctx, out);
}
static int crypto_hmac_md5_import(struct shash_desc *desc, const void *in)
{
struct hmac_md5_ctx *ctx = HMAC_MD5_CTX(desc);
ctx->ostate = HMAC_MD5_KEY(desc->tfm)->ostate;
return __crypto_md5_import(&ctx->hash_ctx, in);
}
static struct shash_alg algs[] = {
{
.base.cra_name = "md5",
.base.cra_driver_name = "md5-lib",
.base.cra_priority = 300,
.base.cra_blocksize = MD5_BLOCK_SIZE,
.base.cra_module = THIS_MODULE,
.digestsize = MD5_DIGEST_SIZE,
.init = crypto_md5_init,
.update = crypto_md5_update,
.final = crypto_md5_final,
.digest = crypto_md5_digest,
.export = crypto_md5_export,
.import = crypto_md5_import,
.descsize = sizeof(struct md5_ctx),
.statesize = MD5_SHASH_STATE_SIZE,
},
{
.base.cra_name = "hmac(md5)",
.base.cra_driver_name = "hmac-md5-lib",
.base.cra_priority = 300,
.base.cra_blocksize = MD5_BLOCK_SIZE,
.base.cra_ctxsize = sizeof(struct hmac_md5_key),
.base.cra_module = THIS_MODULE,
.digestsize = MD5_DIGEST_SIZE,
.setkey = crypto_hmac_md5_setkey,
.init = crypto_hmac_md5_init,
.update = crypto_hmac_md5_update,
.final = crypto_hmac_md5_final,
.digest = crypto_hmac_md5_digest,
.export = crypto_hmac_md5_export,
.import = crypto_hmac_md5_import,
.descsize = sizeof(struct hmac_md5_ctx),
.statesize = MD5_SHASH_STATE_SIZE,
},
};
static int __init md5_mod_init(void)
static int __init crypto_md5_mod_init(void)
{
return crypto_register_shash(&alg);
return crypto_register_shashes(algs, ARRAY_SIZE(algs));
}
module_init(crypto_md5_mod_init);
static void __exit md5_mod_fini(void)
static void __exit crypto_md5_mod_exit(void)
{
crypto_unregister_shash(&alg);
crypto_unregister_shashes(algs, ARRAY_SIZE(algs));
}
module_init(md5_mod_init);
module_exit(md5_mod_fini);
module_exit(crypto_md5_mod_exit);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("MD5 Message Digest Algorithm");
MODULE_DESCRIPTION("Crypto API support for MD5 and HMAC-MD5");
MODULE_ALIAS_CRYPTO("md5");
MODULE_ALIAS_CRYPTO("md5-lib");
MODULE_ALIAS_CRYPTO("hmac(md5)");
MODULE_ALIAS_CRYPTO("hmac-md5-lib");

View file

@ -4178,6 +4178,7 @@ static const struct alg_test_desc alg_test_descs[] = {
}
}, {
.alg = "authenc(hmac(md5),ecb(cipher_null))",
.generic_driver = "authenc(hmac-md5-lib,ecb-cipher_null)",
.test = alg_test_aead,
.suite = {
.aead = __VECS(hmac_md5_ecb_cipher_null_tv_template)
@ -5064,6 +5065,7 @@ static const struct alg_test_desc alg_test_descs[] = {
}
}, {
.alg = "hmac(md5)",
.generic_driver = "hmac-md5-lib",
.test = alg_test_hash,
.suite = {
.hash = __VECS(hmac_md5_tv_template)
@ -5250,6 +5252,7 @@ static const struct alg_test_desc alg_test_descs[] = {
}
}, {
.alg = "md5",
.generic_driver = "md5-lib",
.test = alg_test_hash,
.suite = {
.hash = __VECS(md5_tv_template)

View file

@ -700,7 +700,7 @@ static int img_hash_cra_init(struct crypto_tfm *tfm, const char *alg_name)
static int img_hash_cra_md5_init(struct crypto_tfm *tfm)
{
return img_hash_cra_init(tfm, "md5-generic");
return img_hash_cra_init(tfm, "md5-lib");
}
static int img_hash_cra_sha1_init(struct crypto_tfm *tfm)