crypto: prng - Deterministic CPRNG
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / crypto / ahash.c
CommitLineData
004a403c
LH
1/*
2 * Asynchronous Cryptographic Hash operations.
3 *
4 * This is the asynchronous version of hash.c with notification of
5 * completion via a callback.
6 *
7 * Copyright (c) 2008 Loc Ho <lho@amcc.com>
8 *
9 * This program is free software; you can redistribute it and/or modify it
10 * under the terms of the GNU General Public License as published by the Free
11 * Software Foundation; either version 2 of the License, or (at your option)
12 * any later version.
13 *
14 */
15
16#include <crypto/algapi.h>
17#include <linux/err.h>
18#include <linux/kernel.h>
19#include <linux/module.h>
20#include <linux/sched.h>
21#include <linux/slab.h>
22#include <linux/seq_file.h>
23
24#include "internal.h"
25
26static int ahash_setkey_unaligned(struct crypto_ahash *tfm, const u8 *key,
27 unsigned int keylen)
28{
29 struct ahash_alg *ahash = crypto_ahash_alg(tfm);
30 unsigned long alignmask = crypto_ahash_alignmask(tfm);
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 = ahash->setkey(tfm, alignbuffer, keylen);
43 memset(alignbuffer, 0, keylen);
44 kfree(buffer);
45 return ret;
46}
47
48static int ahash_setkey(struct crypto_ahash *tfm, const u8 *key,
49 unsigned int keylen)
50{
51 struct ahash_alg *ahash = crypto_ahash_alg(tfm);
52 unsigned long alignmask = crypto_ahash_alignmask(tfm);
53
54 if ((unsigned long)key & alignmask)
55 return ahash_setkey_unaligned(tfm, key, keylen);
56
57 return ahash->setkey(tfm, key, keylen);
58}
59
60static unsigned int crypto_ahash_ctxsize(struct crypto_alg *alg, u32 type,
61 u32 mask)
62{
63 return alg->cra_ctxsize;
64}
65
66static int crypto_init_ahash_ops(struct crypto_tfm *tfm, u32 type, u32 mask)
67{
68 struct ahash_alg *alg = &tfm->__crt_alg->cra_ahash;
69 struct ahash_tfm *crt = &tfm->crt_ahash;
70
ca786dc7 71 if (alg->digestsize > PAGE_SIZE / 8)
004a403c
LH
72 return -EINVAL;
73
74 crt->init = alg->init;
75 crt->update = alg->update;
76 crt->final = alg->final;
77 crt->digest = alg->digest;
78 crt->setkey = ahash_setkey;
004a403c
LH
79 crt->digestsize = alg->digestsize;
80
81 return 0;
82}
83
84static void crypto_ahash_show(struct seq_file *m, struct crypto_alg *alg)
85 __attribute__ ((unused));
86static void crypto_ahash_show(struct seq_file *m, struct crypto_alg *alg)
87{
88 seq_printf(m, "type : ahash\n");
89 seq_printf(m, "async : %s\n", alg->cra_flags & CRYPTO_ALG_ASYNC ?
90 "yes" : "no");
91 seq_printf(m, "blocksize : %u\n", alg->cra_blocksize);
92 seq_printf(m, "digestsize : %u\n", alg->cra_hash.digestsize);
93}
94
95const struct crypto_type crypto_ahash_type = {
96 .ctxsize = crypto_ahash_ctxsize,
97 .init = crypto_init_ahash_ops,
98#ifdef CONFIG_PROC_FS
99 .show = crypto_ahash_show,
100#endif
101};
102EXPORT_SYMBOL_GPL(crypto_ahash_type);
103
104MODULE_LICENSE("GPL");
105MODULE_DESCRIPTION("Asynchronous cryptographic hash type");