[CRYPTO] all: Pass tfm instead of ctx to algorithms
[linux-3.10.git] / crypto / digest.c
1 /*
2  * Cryptographic API.
3  *
4  * Digest operations.
5  *
6  * Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
7  *
8  * This program is free software; you can redistribute it and/or modify it
9  * under the terms of the GNU General Public License as published by the Free
10  * Software Foundation; either version 2 of the License, or (at your option) 
11  * any later version.
12  *
13  */
14 #include <linux/crypto.h>
15 #include <linux/mm.h>
16 #include <linux/errno.h>
17 #include <linux/highmem.h>
18 #include <asm/scatterlist.h>
19 #include "internal.h"
20
21 static void init(struct crypto_tfm *tfm)
22 {
23         tfm->__crt_alg->cra_digest.dia_init(tfm);
24 }
25
26 static void update(struct crypto_tfm *tfm,
27                    struct scatterlist *sg, unsigned int nsg)
28 {
29         unsigned int i;
30         unsigned int alignmask = crypto_tfm_alg_alignmask(tfm);
31
32         for (i = 0; i < nsg; i++) {
33
34                 struct page *pg = sg[i].page;
35                 unsigned int offset = sg[i].offset;
36                 unsigned int l = sg[i].length;
37
38                 do {
39                         unsigned int bytes_from_page = min(l, ((unsigned int)
40                                                            (PAGE_SIZE)) - 
41                                                            offset);
42                         char *src = crypto_kmap(pg, 0);
43                         char *p = src + offset;
44
45                         if (unlikely(offset & alignmask)) {
46                                 unsigned int bytes =
47                                         alignmask + 1 - (offset & alignmask);
48                                 bytes = min(bytes, bytes_from_page);
49                                 tfm->__crt_alg->cra_digest.dia_update(tfm, p,
50                                                                       bytes);
51                                 p += bytes;
52                                 bytes_from_page -= bytes;
53                                 l -= bytes;
54                         }
55                         tfm->__crt_alg->cra_digest.dia_update(tfm, p,
56                                                               bytes_from_page);
57                         crypto_kunmap(src, 0);
58                         crypto_yield(tfm);
59                         offset = 0;
60                         pg++;
61                         l -= bytes_from_page;
62                 } while (l > 0);
63         }
64 }
65
66 static void final(struct crypto_tfm *tfm, u8 *out)
67 {
68         unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);
69         if (unlikely((unsigned long)out & alignmask)) {
70                 unsigned int size = crypto_tfm_alg_digestsize(tfm);
71                 u8 buffer[size + alignmask];
72                 u8 *dst = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1);
73                 tfm->__crt_alg->cra_digest.dia_final(crypto_tfm_ctx(tfm), dst);
74                 memcpy(out, dst, size);
75         } else
76                 tfm->__crt_alg->cra_digest.dia_final(crypto_tfm_ctx(tfm), out);
77 }
78
79 static int setkey(struct crypto_tfm *tfm, const u8 *key, unsigned int keylen)
80 {
81         u32 flags;
82         if (tfm->__crt_alg->cra_digest.dia_setkey == NULL)
83                 return -ENOSYS;
84         return tfm->__crt_alg->cra_digest.dia_setkey(tfm, key, keylen, &flags);
85 }
86
87 static void digest(struct crypto_tfm *tfm,
88                    struct scatterlist *sg, unsigned int nsg, u8 *out)
89 {
90         init(tfm);
91         update(tfm, sg, nsg);
92         final(tfm, out);
93 }
94
95 int crypto_init_digest_flags(struct crypto_tfm *tfm, u32 flags)
96 {
97         return flags ? -EINVAL : 0;
98 }
99
100 int crypto_init_digest_ops(struct crypto_tfm *tfm)
101 {
102         struct digest_tfm *ops = &tfm->crt_digest;
103         
104         ops->dit_init   = init;
105         ops->dit_update = update;
106         ops->dit_final  = final;
107         ops->dit_digest = digest;
108         ops->dit_setkey = setkey;
109         
110         return crypto_alloc_hmac_block(tfm);
111 }
112
113 void crypto_exit_digest_ops(struct crypto_tfm *tfm)
114 {
115         crypto_free_hmac_block(tfm);
116 }