arch/mips/crypto/crc32-mips.c

   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                 return -EINVAL;
 182         mctx->key = get_unaligned_le32(key);
 183         return 0;
 184 }
 185
 186 static int chksum_update(struct shash_desc *desc, const u8 *data,
 187                          unsigned int length)
 188 {
 189         struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);
 190
 191         ctx->crc = crc32_mips_le_hw(ctx->crc, data, length);
 192         return 0;
 193 }
 194
 195 static int chksumc_update(struct shash_desc *desc, const u8 *data,
 196                          unsigned int length)
 197 {
 198         struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);
 199
 200         ctx->crc = crc32c_mips_le_hw(ctx->crc, data, length);
 201         return 0;
 202 }
 203
 204 static int chksum_final(struct shash_desc *desc, u8 *out)
 205 {
 206         struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);
 207
 208         put_unaligned_le32(ctx->crc, out);
 209         return 0;
 210 }
 211
 212 static int chksumc_final(struct shash_desc *desc, u8 *out)
 213 {
 214         struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);
 215
 216         put_unaligned_le32(~ctx->crc, out);
 217         return 0;
 218 }
 219
 220 static int __chksum_finup(u32 crc, const u8 *data, unsigned int len, u8 *out)
 221 {
 222         put_unaligned_le32(crc32_mips_le_hw(crc, data, len), out);
 223         return 0;
 224 }
 225
 226 static int __chksumc_finup(u32 crc, const u8 *data, unsigned int len, u8 *out)
 227 {
 228         put_unaligned_le32(~crc32c_mips_le_hw(crc, data, len), out);
 229         return 0;
 230 }
 231
 232 static int chksum_finup(struct shash_desc *desc, const u8 *data,
 233                         unsigned int len, u8 *out)
 234 {
 235         struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);
 236
 237         return __chksum_finup(ctx->crc, data, len, out);
 238 }
 239
 240 static int chksumc_finup(struct shash_desc *desc, const u8 *data,
 241                         unsigned int len, u8 *out)
 242 {
 243         struct chksum_desc_ctx *ctx = shash_desc_ctx(desc);
 244
 245         return __chksumc_finup(ctx->crc, data, len, out);
 246 }
 247
 248 static int chksum_digest(struct shash_desc *desc, const u8 *data,
 249                          unsigned int length, u8 *out)
 250 {
 251         struct chksum_ctx *mctx = crypto_shash_ctx(desc->tfm);
 252
 253         return __chksum_finup(mctx->key, data, length, out);
 254 }
 255
 256 static int chksumc_digest(struct shash_desc *desc, const u8 *data,
 257                          unsigned int length, u8 *out)
 258 {
 259         struct chksum_ctx *mctx = crypto_shash_ctx(desc->tfm);
 260
 261         return __chksumc_finup(mctx->key, data, length, out);
 262 }
 263
 264 static int chksum_cra_init(struct crypto_tfm *tfm)
 265 {
 266         struct chksum_ctx *mctx = crypto_tfm_ctx(tfm);
 267
 268         mctx->key = ~0;
 269         return 0;
 270 }
 271
 272 static struct shash_alg crc32_alg = {
 273         .digestsize             =       CHKSUM_DIGEST_SIZE,
 274         .setkey                 =       chksum_setkey,
 275         .init                   =       chksum_init,
 276         .update                 =       chksum_update,
 277         .final                  =       chksum_final,
 278         .finup                  =       chksum_finup,
 279         .digest                 =       chksum_digest,
 280         .descsize               =       sizeof(struct chksum_desc_ctx),
 281         .base                   =       {
 282                 .cra_name               =       "crc32",
 283                 .cra_driver_name        =       "crc32-mips-hw",
 284                 .cra_priority           =       300,
 285                 .cra_flags              =       CRYPTO_ALG_OPTIONAL_KEY,
 286                 .cra_blocksize          =       CHKSUM_BLOCK_SIZE,
 287                 .cra_alignmask          =       0,
 288                 .cra_ctxsize            =       sizeof(struct chksum_ctx),
 289                 .cra_module             =       THIS_MODULE,
 290                 .cra_init               =       chksum_cra_init,
 291         }
 292 };
 293
 294 static struct shash_alg crc32c_alg = {
 295         .digestsize             =       CHKSUM_DIGEST_SIZE,
 296         .setkey                 =       chksum_setkey,
 297         .init                   =       chksum_init,
 298         .update                 =       chksumc_update,
 299         .final                  =       chksumc_final,
 300         .finup                  =       chksumc_finup,
 301         .digest                 =       chksumc_digest,
 302         .descsize               =       sizeof(struct chksum_desc_ctx),
 303         .base                   =       {
 304                 .cra_name               =       "crc32c",
 305                 .cra_driver_name        =       "crc32c-mips-hw",
 306                 .cra_priority           =       300,
 307                 .cra_flags              =       CRYPTO_ALG_OPTIONAL_KEY,
 308                 .cra_blocksize          =       CHKSUM_BLOCK_SIZE,
 309                 .cra_alignmask          =       0,
 310                 .cra_ctxsize            =       sizeof(struct chksum_ctx),
 311                 .cra_module             =       THIS_MODULE,
 312                 .cra_init               =       chksum_cra_init,
 313         }
 314 };
 315
 316 static int __init crc32_mod_init(void)
 317 {
 318         int err;
 319
 320         err = crypto_register_shash(&crc32_alg);
 321
 322         if (err)
 323                 return err;
 324
 325         err = crypto_register_shash(&crc32c_alg);
 326
 327         if (err) {
 328                 crypto_unregister_shash(&crc32_alg);
 329                 return err;
 330         }
 331
 332         return 0;
 333 }
 334
 335 static void __exit crc32_mod_exit(void)
 336 {
 337         crypto_unregister_shash(&crc32_alg);
 338         crypto_unregister_shash(&crc32c_alg);
 339 }
 340
 341 MODULE_AUTHOR("Marcin Nowakowski <marcin.nowakowski@mips.com");
 342 MODULE_DESCRIPTION("CRC32 and CRC32C using optional MIPS instructions");
 343 MODULE_LICENSE("GPL v2");
 344
 345 module_cpu_feature_match(MIPS_CRC32, crc32_mod_init);
 346 module_exit(crc32_mod_exit);