1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * crc32-mips.c - CRC32 and CRC32C using optional MIPSr6 instructions 4 * 5 * Module based on arm64/crypto/crc32-arm.c 6 * 7 * Copyright (C) 2014 Linaro Ltd <yazen.ghannam@linaro.org> 8 * Copyright (C) 2018 MIPS Tech, LLC 9 */ 10 11 #include <linux/unaligned/access_ok.h> 12 #include <linux/cpufeature.h> 13 #include <linux/init.h> 14 #include <linux/kernel.h> 15 #include <linux/module.h> 16 #include <linux/string.h> 17 #include <asm/mipsregs.h> 18 19 #include <crypto/internal/hash.h> 20 21 enum crc_op_size { 22 b, h, w, d, 23 }; 24 25 enum crc_type { 26 crc32, 27 crc32c, 28 }; 29 30 #ifndef TOOLCHAIN_SUPPORTS_CRC 31 #define _ASM_MACRO_CRC32(OP, SZ, TYPE) \ 32 _ASM_MACRO_3R(OP, rt, rs, rt2, \ 33 ".ifnc \\rt, \\rt2\n\t" \ 34 ".error \"invalid operands \\\"" #OP " \\rt,\\rs,\\rt2\\\"\"\n\t" \ 35 ".endif\n\t" \ 36 _ASM_INSN_IF_MIPS(0x7c00000f | (__rt << 16) | (__rs << 21) | \ 37 ((SZ) << 6) | ((TYPE) << 8)) \ 38 _ASM_INSN32_IF_MM(0x00000030 | (__rs << 16) | (__rt << 21) | \ 39 ((SZ) << 14) | ((TYPE) << 3))) 40 _ASM_MACRO_CRC32(crc32b, 0, 0); 41 _ASM_MACRO_CRC32(crc32h, 1, 0); 42 _ASM_MACRO_CRC32(crc32w, 2, 0); 43 _ASM_MACRO_CRC32(crc32d, 3, 0); 44 _ASM_MACRO_CRC32(crc32cb, 0, 1); 45 _ASM_MACRO_CRC32(crc32ch, 1, 1); 46 _ASM_MACRO_CRC32(crc32cw, 2, 1); 47 _ASM_MACRO_CRC32(crc32cd, 3, 1); 48 #define _ASM_SET_CRC "" 49 #else /* !TOOLCHAIN_SUPPORTS_CRC */ 50 #define _ASM_SET_CRC ".set\tcrc\n\t" 51 #endif 52 53 #define _CRC32(crc, value, size, type) \ 54 do { \ 55 __asm__ __volatile__( \ 56 ".set push\n\t" \ 57 _ASM_SET_CRC \ 58 #type #size " %0, %1, %0\n\t" \ 59 ".set pop" \ 60 : "+r" (crc) \ 61 : "r" (value)); \ 62 } while (0) 63 64 #define CRC32(crc, value, size) \ 65 _CRC32(crc, value, size, crc32) 66 67 #define CRC32C(crc, value, size) \ 68 _CRC32(crc, value, size, crc32c) 69 70 static u32 crc32_mips_le_hw(u32 crc_, const u8 *p, unsigned int len) 71 { 72 u32 crc = crc_; 73 74 #ifdef CONFIG_64BIT 75 while (len >= sizeof(u64)) { 76 u64 value = get_unaligned_le64(p); 77 78 CRC32(crc, value, d); 79 p += sizeof(u64); 80 len -= sizeof(u64); 81 } 82 83 if (len & sizeof(u32)) { 84 #else /* !CONFIG_64BIT */ 85 while (len >= sizeof(u32)) { 86 #endif 87 u32 value = get_unaligned_le32(p); 88 89 CRC32(crc, value, w); 90 p += sizeof(u32); 91 len -= sizeof(u32); 92 } 93 94 if (len & sizeof(u16)) { 95 u16 value = get_unaligned_le16(p); 96 97 CRC32(crc, value, h); 98 p += sizeof(u16); 99 } 100 101 if (len & sizeof(u8)) { 102 u8 value = *p++; 103 104 CRC32(crc, value, b); 105 } 106 107 return crc; 108 } 109 110 static u32 crc32c_mips_le_hw(u32 crc_, const u8 *p, unsigned int len) 111 { 112 u32 crc = crc_; 113 114 #ifdef CONFIG_64BIT 115 while (len >= sizeof(u64)) { 116 u64 value = get_unaligned_le64(p); 117 118 CRC32C(crc, value, d); 119 p += sizeof(u64); 120 len -= sizeof(u64); 121 } 122 123 if (len & sizeof(u32)) { 124 #else /* !CONFIG_64BIT */ 125 while (len >= sizeof(u32)) { 126 #endif 127 u32 value = get_unaligned_le32(p); 128 129 CRC32C(crc, value, w); 130 p += sizeof(u32); 131 len -= sizeof(u32); 132 } 133 134 if (len & sizeof(u16)) { 135 u16 value = get_unaligned_le16(p); 136 137 CRC32C(crc, value, h); 138 p += sizeof(u16); 139 } 140 141 if (len & sizeof(u8)) { 142 u8 value = *p++; 143 144 CRC32C(crc, value, b); 145 } 146 return crc; 147 } 148 149 #define CHKSUM_BLOCK_SIZE 1 150 #define CHKSUM_DIGEST_SIZE 4 151 152 struct chksum_ctx { 153 u32 key; 154 }; 155 156 struct chksum_desc_ctx { 157 u32 crc; 158 }; 159 160 static int chksum_init(struct shash_desc *desc) 161 { 162 struct chksum_ctx *mctx = crypto_shash_ctx(desc->tfm); 163 struct chksum_desc_ctx *ctx = shash_desc_ctx(desc); 164 165 ctx->crc = mctx->key; 166 167 return 0; 168 } 169 170 /* 171 * Setting the seed allows arbitrary accumulators and flexible XOR policy 172 * If your algorithm starts with ~0, then XOR with ~0 before you set 173 * the seed. 174 */ 175 static int chksum_setkey(struct crypto_shash *tfm, const u8 *key, 176 unsigned int keylen) 177 { 178 struct chksum_ctx *mctx = crypto_shash_ctx(tfm); 179 180 if (keylen != sizeof(mctx->key)) { 181 crypto_shash_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN); 182 return -EINVAL; 183 } 184 mctx->key = get_unaligned_le32(key); 185 return 0; 186 } 187 188 static int chksum_update(struct shash_desc *desc, const u8 *data, 189 unsigned int length) 190 { 191 struct chksum_desc_ctx *ctx = shash_desc_ctx(desc); 192 193 ctx->crc = crc32_mips_le_hw(ctx->crc, data, length); 194 return 0; 195 } 196 197 static int chksumc_update(struct shash_desc *desc, const u8 *data, 198 unsigned int length) 199 { 200 struct chksum_desc_ctx *ctx = shash_desc_ctx(desc); 201 202 ctx->crc = crc32c_mips_le_hw(ctx->crc, data, length); 203 return 0; 204 } 205 206 static int chksum_final(struct shash_desc *desc, u8 *out) 207 { 208 struct chksum_desc_ctx *ctx = shash_desc_ctx(desc); 209 210 put_unaligned_le32(ctx->crc, out); 211 return 0; 212 } 213 214 static int chksumc_final(struct shash_desc *desc, u8 *out) 215 { 216 struct chksum_desc_ctx *ctx = shash_desc_ctx(desc); 217 218 put_unaligned_le32(~ctx->crc, out); 219 return 0; 220 } 221 222 static int __chksum_finup(u32 crc, const u8 *data, unsigned int len, u8 *out) 223 { 224 put_unaligned_le32(crc32_mips_le_hw(crc, data, len), out); 225 return 0; 226 } 227 228 static int __chksumc_finup(u32 crc, const u8 *data, unsigned int len, u8 *out) 229 { 230 put_unaligned_le32(~crc32c_mips_le_hw(crc, data, len), out); 231 return 0; 232 } 233 234 static int chksum_finup(struct shash_desc *desc, const u8 *data, 235 unsigned int len, u8 *out) 236 { 237 struct chksum_desc_ctx *ctx = shash_desc_ctx(desc); 238 239 return __chksum_finup(ctx->crc, data, len, out); 240 } 241 242 static int chksumc_finup(struct shash_desc *desc, const u8 *data, 243 unsigned int len, u8 *out) 244 { 245 struct chksum_desc_ctx *ctx = shash_desc_ctx(desc); 246 247 return __chksumc_finup(ctx->crc, data, len, out); 248 } 249 250 static int chksum_digest(struct shash_desc *desc, const u8 *data, 251 unsigned int length, u8 *out) 252 { 253 struct chksum_ctx *mctx = crypto_shash_ctx(desc->tfm); 254 255 return __chksum_finup(mctx->key, data, length, out); 256 } 257 258 static int chksumc_digest(struct shash_desc *desc, const u8 *data, 259 unsigned int length, u8 *out) 260 { 261 struct chksum_ctx *mctx = crypto_shash_ctx(desc->tfm); 262 263 return __chksumc_finup(mctx->key, data, length, out); 264 } 265 266 static int chksum_cra_init(struct crypto_tfm *tfm) 267 { 268 struct chksum_ctx *mctx = crypto_tfm_ctx(tfm); 269 270 mctx->key = ~0; 271 return 0; 272 } 273 274 static struct shash_alg crc32_alg = { 275 .digestsize = CHKSUM_DIGEST_SIZE, 276 .setkey = chksum_setkey, 277 .init = chksum_init, 278 .update = chksum_update, 279 .final = chksum_final, 280 .finup = chksum_finup, 281 .digest = chksum_digest, 282 .descsize = sizeof(struct chksum_desc_ctx), 283 .base = { 284 .cra_name = "crc32", 285 .cra_driver_name = "crc32-mips-hw", 286 .cra_priority = 300, 287 .cra_flags = CRYPTO_ALG_OPTIONAL_KEY, 288 .cra_blocksize = CHKSUM_BLOCK_SIZE, 289 .cra_alignmask = 0, 290 .cra_ctxsize = sizeof(struct chksum_ctx), 291 .cra_module = THIS_MODULE, 292 .cra_init = chksum_cra_init, 293 } 294 }; 295 296 static struct shash_alg crc32c_alg = { 297 .digestsize = CHKSUM_DIGEST_SIZE, 298 .setkey = chksum_setkey, 299 .init = chksum_init, 300 .update = chksumc_update, 301 .final = chksumc_final, 302 .finup = chksumc_finup, 303 .digest = chksumc_digest, 304 .descsize = sizeof(struct chksum_desc_ctx), 305 .base = { 306 .cra_name = "crc32c", 307 .cra_driver_name = "crc32c-mips-hw", 308 .cra_priority = 300, 309 .cra_flags = CRYPTO_ALG_OPTIONAL_KEY, 310 .cra_blocksize = CHKSUM_BLOCK_SIZE, 311 .cra_alignmask = 0, 312 .cra_ctxsize = sizeof(struct chksum_ctx), 313 .cra_module = THIS_MODULE, 314 .cra_init = chksum_cra_init, 315 } 316 }; 317 318 static int __init crc32_mod_init(void) 319 { 320 int err; 321 322 err = crypto_register_shash(&crc32_alg); 323 324 if (err) 325 return err; 326 327 err = crypto_register_shash(&crc32c_alg); 328 329 if (err) { 330 crypto_unregister_shash(&crc32_alg); 331 return err; 332 } 333 334 return 0; 335 } 336 337 static void __exit crc32_mod_exit(void) 338 { 339 crypto_unregister_shash(&crc32_alg); 340 crypto_unregister_shash(&crc32c_alg); 341 } 342 343 MODULE_AUTHOR("Marcin Nowakowski <marcin.nowakowski@mips.com"); 344 MODULE_DESCRIPTION("CRC32 and CRC32C using optional MIPS instructions"); 345 MODULE_LICENSE("GPL v2"); 346 347 module_cpu_feature_match(MIPS_CRC32, crc32_mod_init); 348 module_exit(crc32_mod_exit); 349