Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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kernel
os
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/slab.h>
16#include <linux/seq_file.h>
17
18#include "internal.h"
19
20static unsigned int crypto_hash_ctxsize(struct crypto_alg *alg, u32 type,
21 u32 mask)
22{
23 return alg->cra_ctxsize;
24}
25
26static int hash_setkey_unaligned(struct crypto_hash *crt, const u8 *key,
27 unsigned int keylen)
28{
29 struct crypto_tfm *tfm = crypto_hash_tfm(crt);
30 struct hash_alg *alg = &tfm->__crt_alg->cra_hash;
31 unsigned long alignmask = crypto_hash_alignmask(crt);
32 int ret;
33 u8 *buffer, *alignbuffer;
34 unsigned long absize;
35
36 absize = keylen + alignmask;
37 buffer = kmalloc(absize, GFP_ATOMIC);
38 if (!buffer)
39 return -ENOMEM;
40
41 alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
42 memcpy(alignbuffer, key, keylen);
43 ret = alg->setkey(crt, alignbuffer, keylen);
44 memset(alignbuffer, 0, keylen);
45 kfree(buffer);
46 return ret;
47}
48
49static int hash_setkey(struct crypto_hash *crt, const u8 *key,
50 unsigned int keylen)
51{
52 struct crypto_tfm *tfm = crypto_hash_tfm(crt);
53 struct hash_alg *alg = &tfm->__crt_alg->cra_hash;
54 unsigned long alignmask = crypto_hash_alignmask(crt);
55
56 if ((unsigned long)key & alignmask)
57 return hash_setkey_unaligned(crt, key, keylen);
58
59 return alg->setkey(crt, key, keylen);
60}
61
62static int crypto_init_hash_ops(struct crypto_tfm *tfm, u32 type, u32 mask)
63{
64 struct hash_tfm *crt = &tfm->crt_hash;
65 struct hash_alg *alg = &tfm->__crt_alg->cra_hash;
66
67 if (alg->digestsize > crypto_tfm_alg_blocksize(tfm))
68 return -EINVAL;
69
70 crt->init = alg->init;
71 crt->update = alg->update;
72 crt->final = alg->final;
73 crt->digest = alg->digest;
74 crt->setkey = hash_setkey;
75 crt->digestsize = alg->digestsize;
76
77 return 0;
78}
79
80static void crypto_hash_show(struct seq_file *m, struct crypto_alg *alg)
81 __attribute__ ((unused));
82static void crypto_hash_show(struct seq_file *m, struct crypto_alg *alg)
83{
84 seq_printf(m, "type : hash\n");
85 seq_printf(m, "blocksize : %u\n", alg->cra_blocksize);
86 seq_printf(m, "digestsize : %u\n", alg->cra_hash.digestsize);
87}
88
89const struct crypto_type crypto_hash_type = {
90 .ctxsize = crypto_hash_ctxsize,
91 .init = crypto_init_hash_ops,
92#ifdef CONFIG_PROC_FS
93 .show = crypto_hash_show,
94#endif
95};
96EXPORT_SYMBOL_GPL(crypto_hash_type);
97
98MODULE_LICENSE("GPL");
99MODULE_DESCRIPTION("Generic cryptographic hash type");