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2874c5fd 1// SPDX-License-Identifier: GPL-2.0-or-later
1da177e4
LT
2/*
3 * Cryptographic API.
4 *
e8cfed5e 5 * Single-block cipher operations.
1da177e4
LT
6 *
7 * Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
c774e93e 8 * Copyright (c) 2005 Herbert Xu <herbert@gondor.apana.org.au>
1da177e4 9 */
f1ddcaf3 10
6650c4de 11#include <crypto/algapi.h>
1da177e4
LT
12#include <linux/kernel.h>
13#include <linux/crypto.h>
14#include <linux/errno.h>
791b4d5f 15#include <linux/slab.h>
1da177e4 16#include <linux/string.h>
1da177e4 17#include "internal.h"
1da177e4 18
e8cfed5e 19static int setkey_unaligned(struct crypto_cipher *tfm, const u8 *key,
791b4d5f 20 unsigned int keylen)
ca7c3938 21{
e8cfed5e
EB
22 struct cipher_alg *cia = crypto_cipher_alg(tfm);
23 unsigned long alignmask = crypto_cipher_alignmask(tfm);
ca7c3938
SS
24 int ret;
25 u8 *buffer, *alignbuffer;
26 unsigned long absize;
27
28 absize = keylen + alignmask;
29 buffer = kmalloc(absize, GFP_ATOMIC);
30 if (!buffer)
31 return -ENOMEM;
32
33 alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
34 memcpy(alignbuffer, key, keylen);
e8cfed5e 35 ret = cia->cia_setkey(crypto_cipher_tfm(tfm), alignbuffer, keylen);
06817176 36 memset(alignbuffer, 0, keylen);
ca7c3938
SS
37 kfree(buffer);
38 return ret;
39
40}
41
e8cfed5e
EB
42int crypto_cipher_setkey(struct crypto_cipher *tfm,
43 const u8 *key, unsigned int keylen)
1da177e4 44{
e8cfed5e
EB
45 struct cipher_alg *cia = crypto_cipher_alg(tfm);
46 unsigned long alignmask = crypto_cipher_alignmask(tfm);
ca7c3938 47
674f368a 48 if (keylen < cia->cia_min_keysize || keylen > cia->cia_max_keysize)
1da177e4 49 return -EINVAL;
ca7c3938
SS
50
51 if ((unsigned long)key & alignmask)
52 return setkey_unaligned(tfm, key, keylen);
53
e8cfed5e 54 return cia->cia_setkey(crypto_cipher_tfm(tfm), key, keylen);
1da177e4 55}
e8cfed5e 56EXPORT_SYMBOL_GPL(crypto_cipher_setkey);
1da177e4 57
e8cfed5e
EB
58static inline void cipher_crypt_one(struct crypto_cipher *tfm,
59 u8 *dst, const u8 *src, bool enc)
f28776a3 60{
e8cfed5e
EB
61 unsigned long alignmask = crypto_cipher_alignmask(tfm);
62 struct cipher_alg *cia = crypto_cipher_alg(tfm);
63 void (*fn)(struct crypto_tfm *, u8 *, const u8 *) =
64 enc ? cia->cia_encrypt : cia->cia_decrypt;
f28776a3
HX
65
66 if (unlikely(((unsigned long)dst | (unsigned long)src) & alignmask)) {
e8cfed5e
EB
67 unsigned int bs = crypto_cipher_blocksize(tfm);
68 u8 buffer[MAX_CIPHER_BLOCKSIZE + MAX_CIPHER_ALIGNMASK];
69 u8 *tmp = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
70
71 memcpy(tmp, src, bs);
72 fn(crypto_cipher_tfm(tfm), tmp, tmp);
73 memcpy(dst, tmp, bs);
74 } else {
75 fn(crypto_cipher_tfm(tfm), dst, src);
f28776a3 76 }
f28776a3
HX
77}
78
e8cfed5e
EB
79void crypto_cipher_encrypt_one(struct crypto_cipher *tfm,
80 u8 *dst, const u8 *src)
f28776a3 81{
e8cfed5e 82 cipher_crypt_one(tfm, dst, src, true);
f28776a3 83}
e8cfed5e 84EXPORT_SYMBOL_GPL(crypto_cipher_encrypt_one);
f28776a3 85
e8cfed5e
EB
86void crypto_cipher_decrypt_one(struct crypto_cipher *tfm,
87 u8 *dst, const u8 *src)
1da177e4 88{
e8cfed5e 89 cipher_crypt_one(tfm, dst, src, false);
1da177e4 90}
e8cfed5e 91EXPORT_SYMBOL_GPL(crypto_cipher_decrypt_one);