Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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kernel
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linux
1/*
2 * Cryptographic Hash operations.
3 *
4 * Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au>
5 *
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License as published by the Free
8 * Software Foundation; either version 2 of the License, or (at your option)
9 * any later version.
10 */
11
12#include <linux/errno.h>
13#include <linux/kernel.h>
14#include <linux/module.h>
15#include <linux/seq_file.h>
16
17#include "internal.h"
18
19static unsigned int crypto_hash_ctxsize(struct crypto_alg *alg, u32 type,
20 u32 mask)
21{
22 return alg->cra_ctxsize;
23}
24
25static int hash_setkey_unaligned(struct crypto_hash *crt, const u8 *key,
26 unsigned int keylen)
27{
28 struct crypto_tfm *tfm = crypto_hash_tfm(crt);
29 struct hash_alg *alg = &tfm->__crt_alg->cra_hash;
30 unsigned long alignmask = crypto_hash_alignmask(crt);
31 int ret;
32 u8 *buffer, *alignbuffer;
33 unsigned long absize;
34
35 absize = keylen + alignmask;
36 buffer = kmalloc(absize, GFP_ATOMIC);
37 if (!buffer)
38 return -ENOMEM;
39
40 alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
41 memcpy(alignbuffer, key, keylen);
42 ret = alg->setkey(crt, alignbuffer, keylen);
43 memset(alignbuffer, 0, keylen);
44 kfree(buffer);
45 return ret;
46}
47
48static int hash_setkey(struct crypto_hash *crt, const u8 *key,
49 unsigned int keylen)
50{
51 struct crypto_tfm *tfm = crypto_hash_tfm(crt);
52 struct hash_alg *alg = &tfm->__crt_alg->cra_hash;
53 unsigned long alignmask = crypto_hash_alignmask(crt);
54
55 if ((unsigned long)key & alignmask)
56 return hash_setkey_unaligned(crt, key, keylen);
57
58 return alg->setkey(crt, key, keylen);
59}
60
61static int crypto_init_hash_ops(struct crypto_tfm *tfm, u32 type, u32 mask)
62{
63 struct hash_tfm *crt = &tfm->crt_hash;
64 struct hash_alg *alg = &tfm->__crt_alg->cra_hash;
65
66 if (alg->digestsize > crypto_tfm_alg_blocksize(tfm))
67 return -EINVAL;
68
69 crt->init = alg->init;
70 crt->update = alg->update;
71 crt->final = alg->final;
72 crt->digest = alg->digest;
73 crt->setkey = hash_setkey;
74 crt->digestsize = alg->digestsize;
75
76 return 0;
77}
78
79static void crypto_hash_show(struct seq_file *m, struct crypto_alg *alg)
80 __attribute__ ((unused));
81static void crypto_hash_show(struct seq_file *m, struct crypto_alg *alg)
82{
83 seq_printf(m, "type : hash\n");
84 seq_printf(m, "blocksize : %u\n", alg->cra_blocksize);
85 seq_printf(m, "digestsize : %u\n", alg->cra_hash.digestsize);
86}
87
88const struct crypto_type crypto_hash_type = {
89 .ctxsize = crypto_hash_ctxsize,
90 .init = crypto_init_hash_ops,
91#ifdef CONFIG_PROC_FS
92 .show = crypto_hash_show,
93#endif
94};
95EXPORT_SYMBOL_GPL(crypto_hash_type);
96
97MODULE_LICENSE("GPL");
98MODULE_DESCRIPTION("Generic cryptographic hash type");