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authorTim Chen <tim.c.chen@linux.intel.com>2014-01-23 06:25:47 -0500
committerHerbert Xu <herbert@gondor.apana.org.au>2014-02-25 06:45:04 -0500
commit06e5a1f29819759392239669beb2cad27059c8ec (patch)
tree641318660e841f02bd766ebf1bf375452c106c99 /crypto/crc32c.c
parent883619a931e9f54fca7495321b339669f11cc727 (diff)
CRC32C: Add soft module dependency to load other accelerated crc32c modules
We added the soft module dependency of crc32c module alias to generic crc32c module so other hardware accelerated crc32c modules could get loaded and used before the generic version. We also renamed the crypto/crc32c.c containing the generic crc32c crypto computation to crypto/crc32c_generic.c according to convention. Signed-off-by: Tim Chen <tim.c.chen@linux.intel.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Diffstat (limited to 'crypto/crc32c.c')
-rw-r--r--crypto/crc32c.c172
1 files changed, 0 insertions, 172 deletions
diff --git a/crypto/crc32c.c b/crypto/crc32c.c
deleted file mode 100644
index 06f7018c9d95..000000000000
--- a/crypto/crc32c.c
+++ /dev/null
@@ -1,172 +0,0 @@
1/*
2 * Cryptographic API.
3 *
4 * CRC32C chksum
5 *
6 *@Article{castagnoli-crc,
7 * author = { Guy Castagnoli and Stefan Braeuer and Martin Herrman},
8 * title = {{Optimization of Cyclic Redundancy-Check Codes with 24
9 * and 32 Parity Bits}},
10 * journal = IEEE Transactions on Communication,
11 * year = {1993},
12 * volume = {41},
13 * number = {6},
14 * pages = {},
15 * month = {June},
16 *}
17 * Used by the iSCSI driver, possibly others, and derived from the
18 * the iscsi-crc.c module of the linux-iscsi driver at
19 * http://linux-iscsi.sourceforge.net.
20 *
21 * Following the example of lib/crc32, this function is intended to be
22 * flexible and useful for all users. Modules that currently have their
23 * own crc32c, but hopefully may be able to use this one are:
24 * net/sctp (please add all your doco to here if you change to
25 * use this one!)
26 * <endoflist>
27 *
28 * Copyright (c) 2004 Cisco Systems, Inc.
29 * Copyright (c) 2008 Herbert Xu <herbert@gondor.apana.org.au>
30 *
31 * This program is free software; you can redistribute it and/or modify it
32 * under the terms of the GNU General Public License as published by the Free
33 * Software Foundation; either version 2 of the License, or (at your option)
34 * any later version.
35 *
36 */
37
38#include <crypto/internal/hash.h>
39#include <linux/init.h>
40#include <linux/module.h>
41#include <linux/string.h>
42#include <linux/kernel.h>
43#include <linux/crc32.h>
44
45#define CHKSUM_BLOCK_SIZE 1
46#define CHKSUM_DIGEST_SIZE 4
47
48struct chksum_ctx {
49 u32 key;
50};
51
52struct chksum_desc_ctx {
53 u32 crc;
54};
55
56/*
57 * Steps through buffer one byte at at time, calculates reflected
58 * crc using table.
59 */
60
61static int chksum_init(struct shash_desc *desc)
62{
63 struct chksum_ctx *mctx = crypto_shash_ctx(desc->tfm);
64 struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);
65
66 ctx->crc = mctx->key;
67
68 return 0;
69}
70
71/*
72 * Setting the seed allows arbitrary accumulators and flexible XOR policy
73 * If your algorithm starts with ~0, then XOR with ~0 before you set
74 * the seed.
75 */
76static int chksum_setkey(struct crypto_shash *tfm, const u8 *key,
77 unsigned int keylen)
78{
79 struct chksum_ctx *mctx = crypto_shash_ctx(tfm);
80
81 if (keylen != sizeof(mctx->key)) {
82 crypto_shash_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
83 return -EINVAL;
84 }
85 mctx->key = le32_to_cpu(*(__le32 *)key);
86 return 0;
87}
88
89static int chksum_update(struct shash_desc *desc, const u8 *data,
90 unsigned int length)
91{
92 struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);
93
94 ctx->crc = __crc32c_le(ctx->crc, data, length);
95 return 0;
96}
97
98static int chksum_final(struct shash_desc *desc, u8 *out)
99{
100 struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);
101
102 *(__le32 *)out = ~cpu_to_le32p(&ctx->crc);
103 return 0;
104}
105
106static int __chksum_finup(u32 *crcp, const u8 *data, unsigned int len, u8 *out)
107{
108 *(__le32 *)out = ~cpu_to_le32(__crc32c_le(*crcp, data, len));
109 return 0;
110}
111
112static int chksum_finup(struct shash_desc *desc, const u8 *data,
113 unsigned int len, u8 *out)
114{
115 struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);
116
117 return __chksum_finup(&ctx->crc, data, len, out);
118}
119
120static int chksum_digest(struct shash_desc *desc, const u8 *data,
121 unsigned int length, u8 *out)
122{
123 struct chksum_ctx *mctx = crypto_shash_ctx(desc->tfm);
124
125 return __chksum_finup(&mctx->key, data, length, out);
126}
127
128static int crc32c_cra_init(struct crypto_tfm *tfm)
129{
130 struct chksum_ctx *mctx = crypto_tfm_ctx(tfm);
131
132 mctx->key = ~0;
133 return 0;
134}
135
136static struct shash_alg alg = {
137 .digestsize = CHKSUM_DIGEST_SIZE,
138 .setkey = chksum_setkey,
139 .init = chksum_init,
140 .update = chksum_update,
141 .final = chksum_final,
142 .finup = chksum_finup,
143 .digest = chksum_digest,
144 .descsize = sizeof(struct chksum_desc_ctx),
145 .base = {
146 .cra_name = "crc32c",
147 .cra_driver_name = "crc32c-generic",
148 .cra_priority = 100,
149 .cra_blocksize = CHKSUM_BLOCK_SIZE,
150 .cra_alignmask = 3,
151 .cra_ctxsize = sizeof(struct chksum_ctx),
152 .cra_module = THIS_MODULE,
153 .cra_init = crc32c_cra_init,
154 }
155};
156
157static int __init crc32c_mod_init(void)
158{
159 return crypto_register_shash(&alg);
160}
161
162static void __exit crc32c_mod_fini(void)
163{
164 crypto_unregister_shash(&alg);
165}
166
167module_init(crc32c_mod_init);
168module_exit(crc32c_mod_fini);
169
170MODULE_AUTHOR("Clay Haapala <chaapala@cisco.com>");
171MODULE_DESCRIPTION("CRC32c (Castagnoli) calculations wrapper for lib/crc32c");
172MODULE_LICENSE("GPL");
generated by cgit v1.2.2 (git 2.25.0) at 2024-10-13 10:25:29 -0400