Merge branch 'for-linus' of git://git.kernel.dk/linux-2.6-block
[linux-2.6/mini2440.git] / crypto / digest.c
blob5d3f1303da985417d0ab192c5909aadd5f60ab0b
1 /*
2 * Cryptographic API.
4 * Digest operations.
6 * Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
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.
15 #include <crypto/internal/hash.h>
16 #include <crypto/scatterwalk.h>
17 #include <linux/mm.h>
18 #include <linux/errno.h>
19 #include <linux/hardirq.h>
20 #include <linux/highmem.h>
21 #include <linux/kernel.h>
22 #include <linux/module.h>
23 #include <linux/scatterlist.h>
25 #include "internal.h"
27 static int init(struct hash_desc *desc)
29 struct crypto_tfm *tfm = crypto_hash_tfm(desc->tfm);
31 tfm->__crt_alg->cra_digest.dia_init(tfm);
32 return 0;
35 static int update2(struct hash_desc *desc,
36 struct scatterlist *sg, unsigned int nbytes)
38 struct crypto_tfm *tfm = crypto_hash_tfm(desc->tfm);
39 unsigned int alignmask = crypto_tfm_alg_alignmask(tfm);
41 if (!nbytes)
42 return 0;
44 for (;;) {
45 struct page *pg = sg_page(sg);
46 unsigned int offset = sg->offset;
47 unsigned int l = sg->length;
49 if (unlikely(l > nbytes))
50 l = nbytes;
51 nbytes -= l;
53 do {
54 unsigned int bytes_from_page = min(l, ((unsigned int)
55 (PAGE_SIZE)) -
56 offset);
57 char *src = crypto_kmap(pg, 0);
58 char *p = src + offset;
60 if (unlikely(offset & alignmask)) {
61 unsigned int bytes =
62 alignmask + 1 - (offset & alignmask);
63 bytes = min(bytes, bytes_from_page);
64 tfm->__crt_alg->cra_digest.dia_update(tfm, p,
65 bytes);
66 p += bytes;
67 bytes_from_page -= bytes;
68 l -= bytes;
70 tfm->__crt_alg->cra_digest.dia_update(tfm, p,
71 bytes_from_page);
72 crypto_kunmap(src, 0);
73 crypto_yield(desc->flags);
74 offset = 0;
75 pg++;
76 l -= bytes_from_page;
77 } while (l > 0);
79 if (!nbytes)
80 break;
81 sg = scatterwalk_sg_next(sg);
84 return 0;
87 static int update(struct hash_desc *desc,
88 struct scatterlist *sg, unsigned int nbytes)
90 if (WARN_ON_ONCE(in_irq()))
91 return -EDEADLK;
92 return update2(desc, sg, nbytes);
95 static int final(struct hash_desc *desc, u8 *out)
97 struct crypto_tfm *tfm = crypto_hash_tfm(desc->tfm);
98 unsigned long alignmask = crypto_tfm_alg_alignmask(tfm);
99 struct digest_alg *digest = &tfm->__crt_alg->cra_digest;
101 if (unlikely((unsigned long)out & alignmask)) {
102 unsigned long align = alignmask + 1;
103 unsigned long addr = (unsigned long)crypto_tfm_ctx(tfm);
104 u8 *dst = (u8 *)ALIGN(addr, align) +
105 ALIGN(tfm->__crt_alg->cra_ctxsize, align);
107 digest->dia_final(tfm, dst);
108 memcpy(out, dst, digest->dia_digestsize);
109 } else
110 digest->dia_final(tfm, out);
112 return 0;
115 static int nosetkey(struct crypto_hash *tfm, const u8 *key, unsigned int keylen)
117 crypto_hash_clear_flags(tfm, CRYPTO_TFM_RES_MASK);
118 return -ENOSYS;
121 static int setkey(struct crypto_hash *hash, const u8 *key, unsigned int keylen)
123 struct crypto_tfm *tfm = crypto_hash_tfm(hash);
125 crypto_hash_clear_flags(hash, CRYPTO_TFM_RES_MASK);
126 return tfm->__crt_alg->cra_digest.dia_setkey(tfm, key, keylen);
129 static int digest(struct hash_desc *desc,
130 struct scatterlist *sg, unsigned int nbytes, u8 *out)
132 if (WARN_ON_ONCE(in_irq()))
133 return -EDEADLK;
135 init(desc);
136 update2(desc, sg, nbytes);
137 return final(desc, out);
140 int crypto_init_digest_ops(struct crypto_tfm *tfm)
142 struct hash_tfm *ops = &tfm->crt_hash;
143 struct digest_alg *dalg = &tfm->__crt_alg->cra_digest;
145 if (dalg->dia_digestsize > PAGE_SIZE / 8)
146 return -EINVAL;
148 ops->init = init;
149 ops->update = update;
150 ops->final = final;
151 ops->digest = digest;
152 ops->setkey = dalg->dia_setkey ? setkey : nosetkey;
153 ops->digestsize = dalg->dia_digestsize;
155 return 0;
158 void crypto_exit_digest_ops(struct crypto_tfm *tfm)
162 static int digest_async_nosetkey(struct crypto_ahash *tfm_async, const u8 *key,
163 unsigned int keylen)
165 crypto_ahash_clear_flags(tfm_async, CRYPTO_TFM_RES_MASK);
166 return -ENOSYS;
169 static int digest_async_setkey(struct crypto_ahash *tfm_async, const u8 *key,
170 unsigned int keylen)
172 struct crypto_tfm *tfm = crypto_ahash_tfm(tfm_async);
173 struct digest_alg *dalg = &tfm->__crt_alg->cra_digest;
175 crypto_ahash_clear_flags(tfm_async, CRYPTO_TFM_RES_MASK);
176 return dalg->dia_setkey(tfm, key, keylen);
179 static int digest_async_init(struct ahash_request *req)
181 struct crypto_tfm *tfm = req->base.tfm;
182 struct digest_alg *dalg = &tfm->__crt_alg->cra_digest;
184 dalg->dia_init(tfm);
185 return 0;
188 static int digest_async_update(struct ahash_request *req)
190 struct crypto_tfm *tfm = req->base.tfm;
191 struct hash_desc desc = {
192 .tfm = __crypto_hash_cast(tfm),
193 .flags = req->base.flags,
196 update(&desc, req->src, req->nbytes);
197 return 0;
200 static int digest_async_final(struct ahash_request *req)
202 struct crypto_tfm *tfm = req->base.tfm;
203 struct hash_desc desc = {
204 .tfm = __crypto_hash_cast(tfm),
205 .flags = req->base.flags,
208 final(&desc, req->result);
209 return 0;
212 static int digest_async_digest(struct ahash_request *req)
214 struct crypto_tfm *tfm = req->base.tfm;
215 struct hash_desc desc = {
216 .tfm = __crypto_hash_cast(tfm),
217 .flags = req->base.flags,
220 return digest(&desc, req->src, req->nbytes, req->result);
223 int crypto_init_digest_ops_async(struct crypto_tfm *tfm)
225 struct ahash_tfm *crt = &tfm->crt_ahash;
226 struct digest_alg *dalg = &tfm->__crt_alg->cra_digest;
228 if (dalg->dia_digestsize > PAGE_SIZE / 8)
229 return -EINVAL;
231 crt->init = digest_async_init;
232 crt->update = digest_async_update;
233 crt->final = digest_async_final;
234 crt->digest = digest_async_digest;
235 crt->setkey = dalg->dia_setkey ? digest_async_setkey :
236 digest_async_nosetkey;
237 crt->digestsize = dalg->dia_digestsize;
239 return 0;