Commit | Line | Data |
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0f049f7d | 1 | // SPDX-License-Identifier: GPL-2.0-only |
78c37d19 AB |
2 | /* |
3 | * Copyright 2012 Xyratex Technology Limited | |
4 | */ | |
5 | ||
6 | /* | |
7 | * This is crypto api shash wrappers to crc32_le. | |
8 | */ | |
9 | ||
fffe7d92 | 10 | #include <asm/unaligned.h> |
78c37d19 AB |
11 | #include <linux/crc32.h> |
12 | #include <crypto/internal/hash.h> | |
13 | #include <linux/init.h> | |
14 | #include <linux/module.h> | |
15 | #include <linux/string.h> | |
16 | #include <linux/kernel.h> | |
17 | ||
18 | #define CHKSUM_BLOCK_SIZE 1 | |
19 | #define CHKSUM_DIGEST_SIZE 4 | |
20 | ||
78c37d19 AB |
21 | /** No default init with ~0 */ |
22 | static int crc32_cra_init(struct crypto_tfm *tfm) | |
23 | { | |
24 | u32 *key = crypto_tfm_ctx(tfm); | |
25 | ||
26 | *key = 0; | |
27 | ||
28 | return 0; | |
29 | } | |
30 | ||
78c37d19 AB |
31 | /* |
32 | * Setting the seed allows arbitrary accumulators and flexible XOR policy | |
33 | * If your algorithm starts with ~0, then XOR with ~0 before you set | |
34 | * the seed. | |
35 | */ | |
36 | static int crc32_setkey(struct crypto_shash *hash, const u8 *key, | |
37 | unsigned int keylen) | |
38 | { | |
39 | u32 *mctx = crypto_shash_ctx(hash); | |
40 | ||
674f368a | 41 | if (keylen != sizeof(u32)) |
78c37d19 | 42 | return -EINVAL; |
fffe7d92 | 43 | *mctx = get_unaligned_le32(key); |
78c37d19 AB |
44 | return 0; |
45 | } | |
46 | ||
47 | static int crc32_init(struct shash_desc *desc) | |
48 | { | |
49 | u32 *mctx = crypto_shash_ctx(desc->tfm); | |
50 | u32 *crcp = shash_desc_ctx(desc); | |
51 | ||
52 | *crcp = *mctx; | |
53 | ||
54 | return 0; | |
55 | } | |
56 | ||
57 | static int crc32_update(struct shash_desc *desc, const u8 *data, | |
58 | unsigned int len) | |
59 | { | |
60 | u32 *crcp = shash_desc_ctx(desc); | |
61 | ||
6943546c | 62 | *crcp = crc32_le(*crcp, data, len); |
78c37d19 AB |
63 | return 0; |
64 | } | |
65 | ||
66 | /* No final XOR 0xFFFFFFFF, like crc32_le */ | |
67 | static int __crc32_finup(u32 *crcp, const u8 *data, unsigned int len, | |
68 | u8 *out) | |
69 | { | |
6943546c | 70 | put_unaligned_le32(crc32_le(*crcp, data, len), out); |
78c37d19 AB |
71 | return 0; |
72 | } | |
73 | ||
74 | static int crc32_finup(struct shash_desc *desc, const u8 *data, | |
75 | unsigned int len, u8 *out) | |
76 | { | |
77 | return __crc32_finup(shash_desc_ctx(desc), data, len, out); | |
78 | } | |
79 | ||
80 | static int crc32_final(struct shash_desc *desc, u8 *out) | |
81 | { | |
82 | u32 *crcp = shash_desc_ctx(desc); | |
83 | ||
fffe7d92 | 84 | put_unaligned_le32(*crcp, out); |
78c37d19 AB |
85 | return 0; |
86 | } | |
87 | ||
88 | static int crc32_digest(struct shash_desc *desc, const u8 *data, | |
89 | unsigned int len, u8 *out) | |
90 | { | |
91 | return __crc32_finup(crypto_shash_ctx(desc->tfm), data, len, | |
92 | out); | |
93 | } | |
94 | static struct shash_alg alg = { | |
95 | .setkey = crc32_setkey, | |
96 | .init = crc32_init, | |
97 | .update = crc32_update, | |
98 | .final = crc32_final, | |
99 | .finup = crc32_finup, | |
100 | .digest = crc32_digest, | |
101 | .descsize = sizeof(u32), | |
102 | .digestsize = CHKSUM_DIGEST_SIZE, | |
103 | .base = { | |
104 | .cra_name = "crc32", | |
a7c58ac0 | 105 | .cra_driver_name = "crc32-generic", |
78c37d19 | 106 | .cra_priority = 100, |
a208fa8f | 107 | .cra_flags = CRYPTO_ALG_OPTIONAL_KEY, |
78c37d19 AB |
108 | .cra_blocksize = CHKSUM_BLOCK_SIZE, |
109 | .cra_ctxsize = sizeof(u32), | |
110 | .cra_module = THIS_MODULE, | |
111 | .cra_init = crc32_cra_init, | |
112 | } | |
113 | }; | |
114 | ||
115 | static int __init crc32_mod_init(void) | |
116 | { | |
117 | return crypto_register_shash(&alg); | |
118 | } | |
119 | ||
120 | static void __exit crc32_mod_fini(void) | |
121 | { | |
122 | crypto_unregister_shash(&alg); | |
123 | } | |
124 | ||
c4741b23 | 125 | subsys_initcall(crc32_mod_init); |
78c37d19 AB |
126 | module_exit(crc32_mod_fini); |
127 | ||
128 | MODULE_AUTHOR("Alexander Boyko <alexander_boyko@xyratex.com>"); | |
129 | MODULE_DESCRIPTION("CRC32 calculations wrapper for lib/crc32"); | |
130 | MODULE_LICENSE("GPL"); | |
5d26a105 | 131 | MODULE_ALIAS_CRYPTO("crc32"); |
a7c58ac0 | 132 | MODULE_ALIAS_CRYPTO("crc32-generic"); |