1 | /* |
2 | * Cryptographic API. |
3 | * |
4 | * T10 Data Integrity Field CRC16 Crypto Transform using PCLMULQDQ Instructions |
5 | * |
6 | * Copyright (C) 2013 Intel Corporation |
7 | * Author: Tim Chen <tim.c.chen@linux.intel.com> |
8 | * |
9 | * This program is free software; you can redistribute it and/or modify it |
10 | * under the terms of the GNU General Public License as published by the Free |
11 | * Software Foundation; either version 2 of the License, or (at your option) |
12 | * any later version. |
13 | * |
14 | * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, |
15 | * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF |
16 | * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND |
17 | * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS |
18 | * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN |
19 | * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN |
20 | * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE |
21 | * SOFTWARE. |
22 | * |
23 | */ |
24 | |
25 | #include <linux/types.h> |
26 | #include <linux/module.h> |
27 | #include <linux/crc-t10dif.h> |
28 | #include <crypto/internal/hash.h> |
29 | #include <crypto/internal/simd.h> |
30 | #include <linux/init.h> |
31 | #include <linux/string.h> |
32 | #include <linux/kernel.h> |
33 | #include <asm/cpufeatures.h> |
34 | #include <asm/cpu_device_id.h> |
35 | #include <asm/simd.h> |
36 | |
37 | asmlinkage u16 crc_t10dif_pcl(u16 init_crc, const u8 *buf, size_t len); |
38 | |
39 | struct chksum_desc_ctx { |
40 | __u16 crc; |
41 | }; |
42 | |
43 | static int chksum_init(struct shash_desc *desc) |
44 | { |
45 | struct chksum_desc_ctx *ctx = shash_desc_ctx(desc); |
46 | |
47 | ctx->crc = 0; |
48 | |
49 | return 0; |
50 | } |
51 | |
52 | static int chksum_update(struct shash_desc *desc, const u8 *data, |
53 | unsigned int length) |
54 | { |
55 | struct chksum_desc_ctx *ctx = shash_desc_ctx(desc); |
56 | |
57 | if (length >= 16 && crypto_simd_usable()) { |
58 | kernel_fpu_begin(); |
59 | ctx->crc = crc_t10dif_pcl(init_crc: ctx->crc, buf: data, len: length); |
60 | kernel_fpu_end(); |
61 | } else |
62 | ctx->crc = crc_t10dif_generic(crc: ctx->crc, buffer: data, len: length); |
63 | return 0; |
64 | } |
65 | |
66 | static int chksum_final(struct shash_desc *desc, u8 *out) |
67 | { |
68 | struct chksum_desc_ctx *ctx = shash_desc_ctx(desc); |
69 | |
70 | *(__u16 *)out = ctx->crc; |
71 | return 0; |
72 | } |
73 | |
74 | static int __chksum_finup(__u16 crc, const u8 *data, unsigned int len, u8 *out) |
75 | { |
76 | if (len >= 16 && crypto_simd_usable()) { |
77 | kernel_fpu_begin(); |
78 | *(__u16 *)out = crc_t10dif_pcl(init_crc: crc, buf: data, len); |
79 | kernel_fpu_end(); |
80 | } else |
81 | *(__u16 *)out = crc_t10dif_generic(crc, buffer: data, len); |
82 | return 0; |
83 | } |
84 | |
85 | static int chksum_finup(struct shash_desc *desc, const u8 *data, |
86 | unsigned int len, u8 *out) |
87 | { |
88 | struct chksum_desc_ctx *ctx = shash_desc_ctx(desc); |
89 | |
90 | return __chksum_finup(crc: ctx->crc, data, len, out); |
91 | } |
92 | |
93 | static int chksum_digest(struct shash_desc *desc, const u8 *data, |
94 | unsigned int length, u8 *out) |
95 | { |
96 | return __chksum_finup(crc: 0, data, len: length, out); |
97 | } |
98 | |
99 | static struct shash_alg alg = { |
100 | .digestsize = CRC_T10DIF_DIGEST_SIZE, |
101 | .init = chksum_init, |
102 | .update = chksum_update, |
103 | .final = chksum_final, |
104 | .finup = chksum_finup, |
105 | .digest = chksum_digest, |
106 | .descsize = sizeof(struct chksum_desc_ctx), |
107 | .base = { |
108 | .cra_name = "crct10dif" , |
109 | .cra_driver_name = "crct10dif-pclmul" , |
110 | .cra_priority = 200, |
111 | .cra_blocksize = CRC_T10DIF_BLOCK_SIZE, |
112 | .cra_module = THIS_MODULE, |
113 | } |
114 | }; |
115 | |
116 | static const struct x86_cpu_id crct10dif_cpu_id[] = { |
117 | X86_MATCH_FEATURE(X86_FEATURE_PCLMULQDQ, NULL), |
118 | {} |
119 | }; |
120 | MODULE_DEVICE_TABLE(x86cpu, crct10dif_cpu_id); |
121 | |
122 | static int __init crct10dif_intel_mod_init(void) |
123 | { |
124 | if (!x86_match_cpu(match: crct10dif_cpu_id)) |
125 | return -ENODEV; |
126 | |
127 | return crypto_register_shash(alg: &alg); |
128 | } |
129 | |
130 | static void __exit crct10dif_intel_mod_fini(void) |
131 | { |
132 | crypto_unregister_shash(alg: &alg); |
133 | } |
134 | |
135 | module_init(crct10dif_intel_mod_init); |
136 | module_exit(crct10dif_intel_mod_fini); |
137 | |
138 | MODULE_AUTHOR("Tim Chen <tim.c.chen@linux.intel.com>" ); |
139 | MODULE_DESCRIPTION("T10 DIF CRC calculation accelerated with PCLMULQDQ." ); |
140 | MODULE_LICENSE("GPL" ); |
141 | |
142 | MODULE_ALIAS_CRYPTO("crct10dif" ); |
143 | MODULE_ALIAS_CRYPTO("crct10dif-pclmul" ); |
144 | |