1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Cryptographic API.
4 *
5 * Single-block cipher operations.
6 *
7 * Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
8 * Copyright (c) 2005 Herbert Xu <herbert@gondor.apana.org.au>
9 */
10
11#include <crypto/algapi.h>
12#include <crypto/internal/cipher.h>
13#include <linux/kernel.h>
14#include <linux/crypto.h>
15#include <linux/errno.h>
16#include <linux/slab.h>
17#include <linux/string.h>
18#include "internal.h"
19
20static int setkey_unaligned(struct crypto_cipher *tfm, const u8 *key,
21 unsigned int keylen)
22{
23 struct cipher_alg *cia = crypto_cipher_alg(tfm);
24 unsigned long alignmask = crypto_cipher_alignmask(tfm);
25 int ret;
26 u8 *buffer, *alignbuffer;
27 unsigned long absize;
28
29 absize = keylen + alignmask;
30 buffer = kmalloc(absize, GFP_ATOMIC);
31 if (!buffer)
32 return -ENOMEM;
33
34 alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
35 memcpy(to: alignbuffer, from: key, len: keylen);
36 ret = cia->cia_setkey(crypto_cipher_tfm(tfm), alignbuffer, keylen);
37 kfree_sensitive(objp: buffer);
38 return ret;
39
40}
41
42int crypto_cipher_setkey(struct crypto_cipher *tfm,
43 const u8 *key, unsigned int keylen)
44{
45 struct cipher_alg *cia = crypto_cipher_alg(tfm);
46 unsigned long alignmask = crypto_cipher_alignmask(tfm);
47
48 if (keylen < cia->cia_min_keysize || keylen > cia->cia_max_keysize)
49 return -EINVAL;
50
51 if ((unsigned long)key & alignmask)
52 return setkey_unaligned(tfm, key, keylen);
53
54 return cia->cia_setkey(crypto_cipher_tfm(tfm), key, keylen);
55}
56EXPORT_SYMBOL_NS_GPL(crypto_cipher_setkey, "CRYPTO_INTERNAL");
57
58static inline void cipher_crypt_one(struct crypto_cipher *tfm,
59 u8 *dst, const u8 *src, bool enc)
60{
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;
65
66 if (unlikely(((unsigned long)dst | (unsigned long)src) & alignmask)) {
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(to: tmp, from: src, len: bs);
72 fn(crypto_cipher_tfm(tfm), tmp, tmp);
73 memcpy(to: dst, from: tmp, len: bs);
74 } else {
75 fn(crypto_cipher_tfm(tfm), dst, src);
76 }
77}
78
79void crypto_cipher_encrypt_one(struct crypto_cipher *tfm,
80 u8 *dst, const u8 *src)
81{
82 cipher_crypt_one(tfm, dst, src, enc: true);
83}
84EXPORT_SYMBOL_NS_GPL(crypto_cipher_encrypt_one, "CRYPTO_INTERNAL");
85
86void crypto_cipher_decrypt_one(struct crypto_cipher *tfm,
87 u8 *dst, const u8 *src)
88{
89 cipher_crypt_one(tfm, dst, src, enc: false);
90}
91EXPORT_SYMBOL_NS_GPL(crypto_cipher_decrypt_one, "CRYPTO_INTERNAL");
92
93struct crypto_cipher *crypto_clone_cipher(struct crypto_cipher *cipher)
94{
95 struct crypto_tfm *tfm = crypto_cipher_tfm(tfm: cipher);
96 struct crypto_alg *alg = tfm->__crt_alg;
97 struct crypto_cipher *ncipher;
98 struct crypto_tfm *ntfm;
99
100 if (alg->cra_init)
101 return ERR_PTR(error: -ENOSYS);
102
103 if (unlikely(!crypto_mod_get(alg)))
104 return ERR_PTR(error: -ESTALE);
105
106 ntfm = __crypto_alloc_tfmgfp(alg, CRYPTO_ALG_TYPE_CIPHER,
107 CRYPTO_ALG_TYPE_MASK, GFP_ATOMIC);
108 if (IS_ERR(ptr: ntfm)) {
109 crypto_mod_put(alg);
110 return ERR_CAST(ptr: ntfm);
111 }
112
113 ntfm->crt_flags = tfm->crt_flags;
114
115 ncipher = __crypto_cipher_cast(tfm: ntfm);
116
117 return ncipher;
118}
119EXPORT_SYMBOL_GPL(crypto_clone_cipher);
120