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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 | /* GPL HEADER START * * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 only, * as published by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License version 2 for more details (a copy is included * in the LICENSE file that accompanied this code). * * You should have received a copy of the GNU General Public License * version 2 along with this program; If not, see http://www.gnu.org/licenses * * Please visit http://www.xyratex.com/contact if you need additional * information or have any questions. * * GPL HEADER END */ /* * Copyright 2012 Xyratex Technology Limited * * Wrappers for kernel crypto shash api to pclmulqdq crc32 implementation. */ #include <linux/init.h> #include <linux/module.h> #include <linux/string.h> #include <linux/kernel.h> #include <linux/crc32.h> #include <crypto/internal/hash.h> #include <crypto/internal/simd.h> #include <asm/cpufeatures.h> #include <asm/cpu_device_id.h> #include <asm/simd.h> #define CHKSUM_BLOCK_SIZE 1 #define CHKSUM_DIGEST_SIZE 4 #define PCLMUL_MIN_LEN 64L /* minimum size of buffer * for crc32_pclmul_le_16 */ #define SCALE_F 16L /* size of xmm register */ #define SCALE_F_MASK (SCALE_F - 1) u32 crc32_pclmul_le_16(unsigned char const *buffer, size_t len, u32 crc32); static u32 __attribute__((pure)) crc32_pclmul_le(u32 crc, unsigned char const *p, size_t len) { unsigned int iquotient; unsigned int iremainder; unsigned int prealign; if (len < PCLMUL_MIN_LEN + SCALE_F_MASK || !crypto_simd_usable()) return crc32_le(crc, p, len); if ((long)p & SCALE_F_MASK) { /* align p to 16 byte */ prealign = SCALE_F - ((long)p & SCALE_F_MASK); crc = crc32_le(crc, p, prealign); len -= prealign; p = (unsigned char *)(((unsigned long)p + SCALE_F_MASK) & ~SCALE_F_MASK); } iquotient = len & (~SCALE_F_MASK); iremainder = len & SCALE_F_MASK; kernel_fpu_begin(); crc = crc32_pclmul_le_16(p, iquotient, crc); kernel_fpu_end(); if (iremainder) crc = crc32_le(crc, p + iquotient, iremainder); return crc; } static int crc32_pclmul_cra_init(struct crypto_tfm *tfm) { u32 *key = crypto_tfm_ctx(tfm); *key = 0; return 0; } static int crc32_pclmul_setkey(struct crypto_shash *hash, const u8 *key, unsigned int keylen) { u32 *mctx = crypto_shash_ctx(hash); if (keylen != sizeof(u32)) return -EINVAL; *mctx = le32_to_cpup((__le32 *)key); return 0; } static int crc32_pclmul_init(struct shash_desc *desc) { u32 *mctx = crypto_shash_ctx(desc->tfm); u32 *crcp = shash_desc_ctx(desc); *crcp = *mctx; return 0; } static int crc32_pclmul_update(struct shash_desc *desc, const u8 *data, unsigned int len) { u32 *crcp = shash_desc_ctx(desc); *crcp = crc32_pclmul_le(*crcp, data, len); return 0; } /* No final XOR 0xFFFFFFFF, like crc32_le */ static int __crc32_pclmul_finup(u32 *crcp, const u8 *data, unsigned int len, u8 *out) { *(__le32 *)out = cpu_to_le32(crc32_pclmul_le(*crcp, data, len)); return 0; } static int crc32_pclmul_finup(struct shash_desc *desc, const u8 *data, unsigned int len, u8 *out) { return __crc32_pclmul_finup(shash_desc_ctx(desc), data, len, out); } static int crc32_pclmul_final(struct shash_desc *desc, u8 *out) { u32 *crcp = shash_desc_ctx(desc); *(__le32 *)out = cpu_to_le32p(crcp); return 0; } static int crc32_pclmul_digest(struct shash_desc *desc, const u8 *data, unsigned int len, u8 *out) { return __crc32_pclmul_finup(crypto_shash_ctx(desc->tfm), data, len, out); } static struct shash_alg alg = { .setkey = crc32_pclmul_setkey, .init = crc32_pclmul_init, .update = crc32_pclmul_update, .final = crc32_pclmul_final, .finup = crc32_pclmul_finup, .digest = crc32_pclmul_digest, .descsize = sizeof(u32), .digestsize = CHKSUM_DIGEST_SIZE, .base = { .cra_name = "crc32", .cra_driver_name = "crc32-pclmul", .cra_priority = 200, .cra_flags = CRYPTO_ALG_OPTIONAL_KEY, .cra_blocksize = CHKSUM_BLOCK_SIZE, .cra_ctxsize = sizeof(u32), .cra_module = THIS_MODULE, .cra_init = crc32_pclmul_cra_init, } }; static const struct x86_cpu_id crc32pclmul_cpu_id[] = { X86_MATCH_FEATURE(X86_FEATURE_PCLMULQDQ, NULL), {} }; MODULE_DEVICE_TABLE(x86cpu, crc32pclmul_cpu_id); static int __init crc32_pclmul_mod_init(void) { if (!x86_match_cpu(crc32pclmul_cpu_id)) { pr_info("PCLMULQDQ-NI instructions are not detected.\n"); return -ENODEV; } return crypto_register_shash(&alg); } static void __exit crc32_pclmul_mod_fini(void) { crypto_unregister_shash(&alg); } module_init(crc32_pclmul_mod_init); module_exit(crc32_pclmul_mod_fini); MODULE_AUTHOR("Alexander Boyko <alexander_boyko@xyratex.com>"); MODULE_LICENSE("GPL"); MODULE_ALIAS_CRYPTO("crc32"); MODULE_ALIAS_CRYPTO("crc32-pclmul"); |