mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-11-26 00:51:02 +07:00
a208fa8f33
We need to consistently enforce that keyed hashes cannot be used without setting the key. To do this we need a reliable way to determine whether a given hash algorithm is keyed or not. AF_ALG currently does this by checking for the presence of a ->setkey() method. However, this is actually slightly broken because the CRC-32 algorithms implement ->setkey() but can also be used without a key. (The CRC-32 "key" is not actually a cryptographic key but rather represents the initial state. If not overridden, then a default initial state is used.) Prepare to fix this by introducing a flag CRYPTO_ALG_OPTIONAL_KEY which indicates that the algorithm has a ->setkey() method, but it is not required to be called. Then set it on all the CRC-32 algorithms. The same also applies to the Adler-32 implementation in Lustre. Also, the cryptd and mcryptd templates have to pass through the flag from their underlying algorithm. Cc: stable@vger.kernel.org Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
162 lines
3.8 KiB
C
162 lines
3.8 KiB
C
/* GPL HEADER START
|
|
*
|
|
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License version 2 only,
|
|
* as published by the Free Software Foundation.
|
|
*
|
|
* This program is distributed in the hope that it will be useful, but
|
|
* WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
* General Public License version 2 for more details (a copy is included
|
|
* in the LICENSE file that accompanied this code).
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* version 2 along with this program; If not, see http://www.gnu.org/licenses
|
|
*
|
|
* Please visit http://www.xyratex.com/contact if you need additional
|
|
* information or have any questions.
|
|
*
|
|
* GPL HEADER END
|
|
*/
|
|
|
|
/*
|
|
* Copyright 2012 Xyratex Technology Limited
|
|
*/
|
|
|
|
/*
|
|
* This is crypto api shash wrappers to crc32_le.
|
|
*/
|
|
|
|
#include <linux/crc32.h>
|
|
#include <crypto/internal/hash.h>
|
|
#include <linux/init.h>
|
|
#include <linux/module.h>
|
|
#include <linux/string.h>
|
|
#include <linux/kernel.h>
|
|
|
|
#define CHKSUM_BLOCK_SIZE 1
|
|
#define CHKSUM_DIGEST_SIZE 4
|
|
|
|
static u32 __crc32_le(u32 crc, unsigned char const *p, size_t len)
|
|
{
|
|
return crc32_le(crc, p, len);
|
|
}
|
|
|
|
/** No default init with ~0 */
|
|
static int crc32_cra_init(struct crypto_tfm *tfm)
|
|
{
|
|
u32 *key = crypto_tfm_ctx(tfm);
|
|
|
|
*key = 0;
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
/*
|
|
* Setting the seed allows arbitrary accumulators and flexible XOR policy
|
|
* If your algorithm starts with ~0, then XOR with ~0 before you set
|
|
* the seed.
|
|
*/
|
|
static int crc32_setkey(struct crypto_shash *hash, const u8 *key,
|
|
unsigned int keylen)
|
|
{
|
|
u32 *mctx = crypto_shash_ctx(hash);
|
|
|
|
if (keylen != sizeof(u32)) {
|
|
crypto_shash_set_flags(hash, CRYPTO_TFM_RES_BAD_KEY_LEN);
|
|
return -EINVAL;
|
|
}
|
|
*mctx = le32_to_cpup((__le32 *)key);
|
|
return 0;
|
|
}
|
|
|
|
static int crc32_init(struct shash_desc *desc)
|
|
{
|
|
u32 *mctx = crypto_shash_ctx(desc->tfm);
|
|
u32 *crcp = shash_desc_ctx(desc);
|
|
|
|
*crcp = *mctx;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int crc32_update(struct shash_desc *desc, const u8 *data,
|
|
unsigned int len)
|
|
{
|
|
u32 *crcp = shash_desc_ctx(desc);
|
|
|
|
*crcp = __crc32_le(*crcp, data, len);
|
|
return 0;
|
|
}
|
|
|
|
/* No final XOR 0xFFFFFFFF, like crc32_le */
|
|
static int __crc32_finup(u32 *crcp, const u8 *data, unsigned int len,
|
|
u8 *out)
|
|
{
|
|
*(__le32 *)out = cpu_to_le32(__crc32_le(*crcp, data, len));
|
|
return 0;
|
|
}
|
|
|
|
static int crc32_finup(struct shash_desc *desc, const u8 *data,
|
|
unsigned int len, u8 *out)
|
|
{
|
|
return __crc32_finup(shash_desc_ctx(desc), data, len, out);
|
|
}
|
|
|
|
static int crc32_final(struct shash_desc *desc, u8 *out)
|
|
{
|
|
u32 *crcp = shash_desc_ctx(desc);
|
|
|
|
*(__le32 *)out = cpu_to_le32p(crcp);
|
|
return 0;
|
|
}
|
|
|
|
static int crc32_digest(struct shash_desc *desc, const u8 *data,
|
|
unsigned int len, u8 *out)
|
|
{
|
|
return __crc32_finup(crypto_shash_ctx(desc->tfm), data, len,
|
|
out);
|
|
}
|
|
static struct shash_alg alg = {
|
|
.setkey = crc32_setkey,
|
|
.init = crc32_init,
|
|
.update = crc32_update,
|
|
.final = crc32_final,
|
|
.finup = crc32_finup,
|
|
.digest = crc32_digest,
|
|
.descsize = sizeof(u32),
|
|
.digestsize = CHKSUM_DIGEST_SIZE,
|
|
.base = {
|
|
.cra_name = "crc32",
|
|
.cra_driver_name = "crc32-generic",
|
|
.cra_priority = 100,
|
|
.cra_flags = CRYPTO_ALG_OPTIONAL_KEY,
|
|
.cra_blocksize = CHKSUM_BLOCK_SIZE,
|
|
.cra_ctxsize = sizeof(u32),
|
|
.cra_module = THIS_MODULE,
|
|
.cra_init = crc32_cra_init,
|
|
}
|
|
};
|
|
|
|
static int __init crc32_mod_init(void)
|
|
{
|
|
return crypto_register_shash(&alg);
|
|
}
|
|
|
|
static void __exit crc32_mod_fini(void)
|
|
{
|
|
crypto_unregister_shash(&alg);
|
|
}
|
|
|
|
module_init(crc32_mod_init);
|
|
module_exit(crc32_mod_fini);
|
|
|
|
MODULE_AUTHOR("Alexander Boyko <alexander_boyko@xyratex.com>");
|
|
MODULE_DESCRIPTION("CRC32 calculations wrapper for lib/crc32");
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_ALIAS_CRYPTO("crc32");
|
|
MODULE_ALIAS_CRYPTO("crc32-generic");
|