Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
os
linux
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
21static void init(struct crypto_tfm *tfm)
22{
23 tfm->__crt_alg->cra_digest.dia_init(crypto_tfm_ctx(tfm));
24}
25
26static void update(struct crypto_tfm *tfm,
27 struct scatterlist *sg, unsigned int nsg)
28{
29 unsigned int i;
30
31 for (i = 0; i < nsg; i++) {
32
33 struct page *pg = sg[i].page;
34 unsigned int offset = sg[i].offset;
35 unsigned int l = sg[i].length;
36
37 do {
38 unsigned int bytes_from_page = min(l, ((unsigned int)
39 (PAGE_SIZE)) -
40 offset);
41 char *p = crypto_kmap(pg, 0) + offset;
42
43 tfm->__crt_alg->cra_digest.dia_update
44 (crypto_tfm_ctx(tfm), p,
45 bytes_from_page);
46 crypto_kunmap(p, 0);
47 crypto_yield(tfm);
48 offset = 0;
49 pg++;
50 l -= bytes_from_page;
51 } while (l > 0);
52 }
53}
54
55static void final(struct crypto_tfm *tfm, u8 *out)
56{
57 tfm->__crt_alg->cra_digest.dia_final(crypto_tfm_ctx(tfm), out);
58}
59
60static int setkey(struct crypto_tfm *tfm, const u8 *key, unsigned int keylen)
61{
62 u32 flags;
63 if (tfm->__crt_alg->cra_digest.dia_setkey == NULL)
64 return -ENOSYS;
65 return tfm->__crt_alg->cra_digest.dia_setkey(crypto_tfm_ctx(tfm),
66 key, keylen, &flags);
67}
68
69static void digest(struct crypto_tfm *tfm,
70 struct scatterlist *sg, unsigned int nsg, u8 *out)
71{
72 unsigned int i;
73
74 tfm->crt_digest.dit_init(tfm);
75
76 for (i = 0; i < nsg; i++) {
77 char *p = crypto_kmap(sg[i].page, 0) + sg[i].offset;
78 tfm->__crt_alg->cra_digest.dia_update(crypto_tfm_ctx(tfm),
79 p, sg[i].length);
80 crypto_kunmap(p, 0);
81 crypto_yield(tfm);
82 }
83 crypto_digest_final(tfm, out);
84}
85
86int crypto_init_digest_flags(struct crypto_tfm *tfm, u32 flags)
87{
88 return flags ? -EINVAL : 0;
89}
90
91int crypto_init_digest_ops(struct crypto_tfm *tfm)
92{
93 struct digest_tfm *ops = &tfm->crt_digest;
94
95 ops->dit_init = init;
96 ops->dit_update = update;
97 ops->dit_final = final;
98 ops->dit_digest = digest;
99 ops->dit_setkey = setkey;
100
101 return crypto_alloc_hmac_block(tfm);
102}
103
104void crypto_exit_digest_ops(struct crypto_tfm *tfm)
105{
106 crypto_free_hmac_block(tfm);
107}