[CRYPTO] digest: Remove old HMAC implementation
[linux-2.6.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
15 #include <linux/mm.h>
16 #include <linux/errno.h>
17 #include <linux/highmem.h>
18 #include <linux/module.h>
19 #include <linux/scatterlist.h>
20
21 #include "internal.h"
22 #include "scatterwalk.h"
23
24 void crypto_digest_init(struct crypto_tfm *tfm)
25 {
26         struct crypto_hash *hash = crypto_hash_cast(tfm);
27         struct hash_desc desc = { .tfm = hash, .flags = tfm->crt_flags };
28
29         crypto_hash_init(&desc);
30 }
31 EXPORT_SYMBOL_GPL(crypto_digest_init);
32
33 void crypto_digest_update(struct crypto_tfm *tfm,
34                           struct scatterlist *sg, unsigned int nsg)
35 {
36         struct crypto_hash *hash = crypto_hash_cast(tfm);
37         struct hash_desc desc = { .tfm = hash, .flags = tfm->crt_flags };
38         unsigned int nbytes = 0;
39         unsigned int i;
40
41         for (i = 0; i < nsg; i++)
42                 nbytes += sg[i].length;
43
44         crypto_hash_update(&desc, sg, nbytes);
45 }
46 EXPORT_SYMBOL_GPL(crypto_digest_update);
47
48 void crypto_digest_final(struct crypto_tfm *tfm, u8 *out)
49 {
50         struct crypto_hash *hash = crypto_hash_cast(tfm);
51         struct hash_desc desc = { .tfm = hash, .flags = tfm->crt_flags };
52
53         crypto_hash_final(&desc, out);
54 }
55 EXPORT_SYMBOL_GPL(crypto_digest_final);
56
57 void crypto_digest_digest(struct crypto_tfm *tfm,
58                           struct scatterlist *sg, unsigned int nsg, u8 *out)
59 {
60         struct crypto_hash *hash = crypto_hash_cast(tfm);
61         struct hash_desc desc = { .tfm = hash, .flags = tfm->crt_flags };
62         unsigned int nbytes = 0;
63         unsigned int i;
64
65         for (i = 0; i < nsg; i++)
66                 nbytes += sg[i].length;
67
68         crypto_hash_digest(&desc, sg, nbytes, out);
69 }
70 EXPORT_SYMBOL_GPL(crypto_digest_digest);
71
72 static int init(struct hash_desc *desc)
73 {
74         struct crypto_tfm *tfm = crypto_hash_tfm(desc->tfm);
75
76         tfm->__crt_alg->cra_digest.dia_init(tfm);
77         return 0;
78 }
79
80 static int update(struct hash_desc *desc,
81                   struct scatterlist *sg, unsigned int nbytes)
82 {
83         struct crypto_tfm *tfm = crypto_hash_tfm(desc->tfm);
84         unsigned int alignmask = crypto_tfm_alg_alignmask(tfm);
85
86         if (!nbytes)
87                 return 0;
88
89         for (;;) {
90                 struct page *pg = sg->page;
91                 unsigned int offset = sg->offset;
92                 unsigned int l = sg->length;
93
94                 if (unlikely(l > nbytes))
95                         l = nbytes;
96                 nbytes -= l;
97
98                 do {
99                         unsigned int bytes_from_page = min(l, ((unsigned int)
100                                                            (PAGE_SIZE)) - 
101                                                            offset);
102                         char *src = crypto_kmap(pg, 0);
103                         char *p = src + offset;
104
105                         if (unlikely(offset & alignmask)) {
106                                 unsigned int bytes =
107                                         alignmask + 1 - (offset & alignmask);
108                                 bytes = min(bytes, bytes_from_page);
109                                 tfm->__crt_alg->cra_digest.dia_update(tfm, p,
110                                                                       bytes);
111                                 p += bytes;
112                                 bytes_from_page -= bytes;
113                                 l -= bytes;
114                         }
115                         tfm->__crt_alg->cra_digest.dia_update(tfm, p,
116                                                               bytes_from_page);
117                         crypto_kunmap(src, 0);
118                         crypto_yield(desc->flags);
119                         offset = 0;
120                         pg++;
121                         l -= bytes_from_page;
122                 } while (l > 0);
123
124                 if (!nbytes)
125                         break;
126                 sg = sg_next(sg);
127         }
128
129         return 0;
130 }
131
132 static int final(struct hash_desc *desc, u8 *out)
133 {
134         struct crypto_tfm *tfm = crypto_hash_tfm(desc->tfm);
135         unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);
136         struct digest_alg *digest = &tfm->__crt_alg->cra_digest;
137
138         if (unlikely((unsigned long)out & alignmask)) {
139                 unsigned long align = alignmask + 1;
140                 unsigned long addr = (unsigned long)crypto_tfm_ctx(tfm);
141                 u8 *dst = (u8 *)ALIGN(addr, align) +
142                           ALIGN(tfm->__crt_alg->cra_ctxsize, align);
143
144                 digest->dia_final(tfm, dst);
145                 memcpy(out, dst, digest->dia_digestsize);
146         } else
147                 digest->dia_final(tfm, out);
148
149         return 0;
150 }
151
152 static int nosetkey(struct crypto_hash *tfm, const u8 *key, unsigned int keylen)
153 {
154         crypto_hash_clear_flags(tfm, CRYPTO_TFM_RES_MASK);
155         return -ENOSYS;
156 }
157
158 static int setkey(struct crypto_hash *hash, const u8 *key, unsigned int keylen)
159 {
160         struct crypto_tfm *tfm = crypto_hash_tfm(hash);
161
162         crypto_hash_clear_flags(hash, CRYPTO_TFM_RES_MASK);
163         return tfm->__crt_alg->cra_digest.dia_setkey(tfm, key, keylen);
164 }
165
166 static int digest(struct hash_desc *desc,
167                   struct scatterlist *sg, unsigned int nbytes, u8 *out)
168 {
169         init(desc);
170         update(desc, sg, nbytes);
171         return final(desc, out);
172 }
173
174 int crypto_init_digest_flags(struct crypto_tfm *tfm, u32 flags)
175 {
176         return flags ? -EINVAL : 0;
177 }
178
179 int crypto_init_digest_ops(struct crypto_tfm *tfm)
180 {
181         struct hash_tfm *ops = &tfm->crt_hash;
182         struct digest_alg *dalg = &tfm->__crt_alg->cra_digest;
183
184         if (dalg->dia_digestsize > crypto_tfm_alg_blocksize(tfm))
185                 return -EINVAL;
186         
187         ops->init       = init;
188         ops->update     = update;
189         ops->final      = final;
190         ops->digest     = digest;
191         ops->setkey     = dalg->dia_setkey ? setkey : nosetkey;
192         ops->digestsize = dalg->dia_digestsize;
193         
194         return 0;
195 }
196
197 void crypto_exit_digest_ops(struct crypto_tfm *tfm)
198 {
199 }