1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * crc32.c - CRC32 and CRC32C using LoongArch crc* instructions
4 *
5 * Module based on mips/crypto/crc32-mips.c
6 *
7 * Copyright (C) 2014 Linaro Ltd <yazen.ghannam@linaro.org>
8 * Copyright (C) 2018 MIPS Tech, LLC
9 * Copyright (C) 2020-2023 Loongson Technology Corporation Limited
10 */
11
12 #include <linux/module.h>
13 #include <crypto/internal/hash.h>
14
15 #include <asm/cpu-features.h>
16 #include <asm/unaligned.h>
17
18 #define _CRC32(crc, value, size, type) \
19 do { \
20 __asm__ __volatile__( \
21 #type ".w." #size ".w" " %0, %1, %0\n\t"\
22 : "+r" (crc) \
23 : "r" (value) \
24 : "memory"); \
25 } while (0)
26
27 #define CRC32(crc, value, size) _CRC32(crc, value, size, crc)
28 #define CRC32C(crc, value, size) _CRC32(crc, value, size, crcc)
29
30 static u32 crc32_loongarch_hw(u32 crc_, const u8 *p, unsigned int len)
31 {
32 u32 crc = crc_;
33
34 while (len >= sizeof(u64)) {
35 u64 value = get_unaligned_le64(p);
36
37 CRC32(crc, value, d);
38 p += sizeof(u64);
39 len -= sizeof(u64);
40 }
41
42 if (len & sizeof(u32)) {
43 u32 value = get_unaligned_le32(p);
44
45 CRC32(crc, value, w);
46 p += sizeof(u32);
47 }
48
49 if (len & sizeof(u16)) {
50 u16 value = get_unaligned_le16(p);
51
52 CRC32(crc, value, h);
53 p += sizeof(u16);
54 }
55
56 if (len & sizeof(u8)) {
57 u8 value = *p++;
58
59 CRC32(crc, value, b);
60 }
61
62 return crc;
63 }
64
65 static u32 crc32c_loongarch_hw(u32 crc_, const u8 *p, unsigned int len)
66 {
67 u32 crc = crc_;
68
69 while (len >= sizeof(u64)) {
70 u64 value = get_unaligned_le64(p);
71
72 CRC32C(crc, value, d);
73 p += sizeof(u64);
74 len -= sizeof(u64);
75 }
76
77 if (len & sizeof(u32)) {
78 u32 value = get_unaligned_le32(p);
79
80 CRC32C(crc, value, w);
81 p += sizeof(u32);
82 }
83
84 if (len & sizeof(u16)) {
85 u16 value = get_unaligned_le16(p);
86
87 CRC32C(crc, value, h);
88 p += sizeof(u16);
89 }
90
91 if (len & sizeof(u8)) {
92 u8 value = *p++;
93
94 CRC32C(crc, value, b);
95 }
96
97 return crc;
98 }
99
100 #define CHKSUM_BLOCK_SIZE 1
101 #define CHKSUM_DIGEST_SIZE 4
102
103 struct chksum_ctx {
104 u32 key;
105 };
106
107 struct chksum_desc_ctx {
108 u32 crc;
109 };
110
111 static int chksum_init(struct shash_desc *desc)
112 {
113 struct chksum_ctx *mctx = crypto_shash_ctx(desc->tfm);
114 struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);
115
116 ctx->crc = mctx->key;
117
118 return 0;
119 }
120
121 /*
122 * Setting the seed allows arbitrary accumulators and flexible XOR policy
123 * If your algorithm starts with ~0, then XOR with ~0 before you set the seed.
124 */
125 static int chksum_setkey(struct crypto_shash *tfm, const u8 *key, unsigned int keylen)
126 {
127 struct chksum_ctx *mctx = crypto_shash_ctx(tfm);
128
129 if (keylen != sizeof(mctx->key))
130 return -EINVAL;
131
132 mctx->key = get_unaligned_le32(key);
133
134 return 0;
135 }
136
137 static int chksum_update(struct shash_desc *desc, const u8 *data, unsigned int length)
138 {
139 struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);
140
141 ctx->crc = crc32_loongarch_hw(ctx->crc, data, length);
142 return 0;
143 }
144
145 static int chksumc_update(struct shash_desc *desc, const u8 *data, unsigned int length)
146 {
147 struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);
148
149 ctx->crc = crc32c_loongarch_hw(ctx->crc, data, length);
150 return 0;
151 }
152
153 static int chksum_final(struct shash_desc *desc, u8 *out)
154 {
155 struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);
156
157 put_unaligned_le32(ctx->crc, out);
158 return 0;
159 }
160
161 static int chksumc_final(struct shash_desc *desc, u8 *out)
162 {
163 struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);
164
165 put_unaligned_le32(~ctx->crc, out);
166 return 0;
167 }
168
169 static int __chksum_finup(u32 crc, const u8 *data, unsigned int len, u8 *out)
170 {
171 put_unaligned_le32(crc32_loongarch_hw(crc, data, len), out);
172 return 0;
173 }
174
175 static int __chksumc_finup(u32 crc, const u8 *data, unsigned int len, u8 *out)
176 {
177 put_unaligned_le32(~crc32c_loongarch_hw(crc, data, len), out);
178 return 0;
179 }
180
181 static int chksum_finup(struct shash_desc *desc, const u8 *data, unsigned int len, u8 *out)
182 {
183 struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);
184
185 return __chksum_finup(ctx->crc, data, len, out);
186 }
187
188 static int chksumc_finup(struct shash_desc *desc, const u8 *data, unsigned int len, u8 *out)
189 {
190 struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);
191
192 return __chksumc_finup(ctx->crc, data, len, out);
193 }
194
195 static int chksum_digest(struct shash_desc *desc, const u8 *data, unsigned int length, u8 *out)
196 {
197 struct chksum_ctx *mctx = crypto_shash_ctx(desc->tfm);
198
199 return __chksum_finup(mctx->key, data, length, out);
200 }
201
202 static int chksumc_digest(struct shash_desc *desc, const u8 *data, unsigned int length, u8 *out)
203 {
204 struct chksum_ctx *mctx = crypto_shash_ctx(desc->tfm);
205
206 return __chksumc_finup(mctx->key, data, length, out);
207 }
208
209 static int chksum_cra_init(struct crypto_tfm *tfm)
210 {
211 struct chksum_ctx *mctx = crypto_tfm_ctx(tfm);
212
213 mctx->key = 0;
214 return 0;
215 }
216
217 static int chksumc_cra_init(struct crypto_tfm *tfm)
218 {
219 struct chksum_ctx *mctx = crypto_tfm_ctx(tfm);
220
221 mctx->key = ~0;
222 return 0;
223 }
224
225 static struct shash_alg crc32_alg = {
226 .digestsize = CHKSUM_DIGEST_SIZE,
227 .setkey = chksum_setkey,
228 .init = chksum_init,
229 .update = chksum_update,
230 .final = chksum_final,
231 .finup = chksum_finup,
232 .digest = chksum_digest,
233 .descsize = sizeof(struct chksum_desc_ctx),
234 .base = {
235 .cra_name = "crc32",
236 .cra_driver_name = "crc32-loongarch",
237 .cra_priority = 300,
238 .cra_flags = CRYPTO_ALG_OPTIONAL_KEY,
239 .cra_blocksize = CHKSUM_BLOCK_SIZE,
240 .cra_ctxsize = sizeof(struct chksum_ctx),
241 .cra_module = THIS_MODULE,
242 .cra_init = chksum_cra_init,
243 }
244 };
245
246 static struct shash_alg crc32c_alg = {
247 .digestsize = CHKSUM_DIGEST_SIZE,
248 .setkey = chksum_setkey,
249 .init = chksum_init,
250 .update = chksumc_update,
251 .final = chksumc_final,
252 .finup = chksumc_finup,
253 .digest = chksumc_digest,
254 .descsize = sizeof(struct chksum_desc_ctx),
255 .base = {
256 .cra_name = "crc32c",
257 .cra_driver_name = "crc32c-loongarch",
258 .cra_priority = 300,
259 .cra_flags = CRYPTO_ALG_OPTIONAL_KEY,
260 .cra_blocksize = CHKSUM_BLOCK_SIZE,
261 .cra_ctxsize = sizeof(struct chksum_ctx),
262 .cra_module = THIS_MODULE,
263 .cra_init = chksumc_cra_init,
264 }
265 };
266
267 static int __init crc32_mod_init(void)
268 {
269 int err;
270
271 if (!cpu_has(CPU_FEATURE_CRC32))
272 return 0;
273
274 err = crypto_register_shash(&crc32_alg);
275 if (err)
276 return err;
277
278 err = crypto_register_shash(&crc32c_alg);
279 if (err)
280 return err;
281
282 return 0;
283 }
284
285 static void __exit crc32_mod_exit(void)
286 {
287 if (!cpu_has(CPU_FEATURE_CRC32))
288 return;
289
290 crypto_unregister_shash(&crc32_alg);
291 crypto_unregister_shash(&crc32c_alg);
292 }
293
294 module_init(crc32_mod_init);
295 module_exit(crc32_mod_exit);
296
297 MODULE_AUTHOR("Min Zhou <zhoumin@loongson.cn>");
298 MODULE_AUTHOR("Huacai Chen <chenhuacai@loongson.cn>");
299 MODULE_DESCRIPTION("CRC32 and CRC32C using LoongArch crc* instructions");
300 MODULE_LICENSE("GPL v2");
301
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