1 /* 2 * Cryptographic API. 3 * 4 * MD5 Message Digest Algorithm (RFC1321). 5 * 6 * Derived from cryptoapi implementation, originally based on the 7 * public domain implementation written by Colin Plumb in 1993. 8 * 9 * Copyright (c) Cryptoapi developers. 10 * Copyright (c) 2002 James Morris <jmorris@intercode.com.au> 11 * 12 * This program is free software; you can redistribute it and/or modify it 13 * under the terms of the GNU General Public License as published by the Free 14 * Software Foundation; either version 2 of the License, or (at your option) 15 * any later version. 16 * 17 */ 18 #include <crypto/internal/hash.h> 19 #include <crypto/md5.h> 20 #include <linux/init.h> 21 #include <linux/module.h> 22 #include <linux/string.h> 23 #include <linux/types.h> 24 #include <asm/byteorder.h> 25 26 #define F1(x, y, z) (z ^ (x & (y ^ z))) 27 #define F2(x, y, z) F1(z, x, y) 28 #define F3(x, y, z) (x ^ y ^ z) 29 #define F4(x, y, z) (y ^ (x | ~z)) 30 31 #define MD5STEP(f, w, x, y, z, in, s) \ 32 (w += f(x, y, z) + in, w = (w<<s | w>>(32-s)) + x) 33 34 static void md5_transform(u32 *hash, u32 const *in) 35 { 36 u32 a, b, c, d; 37 38 a = hash[0]; 39 b = hash[1]; 40 c = hash[2]; 41 d = hash[3]; 42 43 MD5STEP(F1, a, b, c, d, in[0] + 0xd76aa478, 7); 44 MD5STEP(F1, d, a, b, c, in[1] + 0xe8c7b756, 12); 45 MD5STEP(F1, c, d, a, b, in[2] + 0x242070db, 17); 46 MD5STEP(F1, b, c, d, a, in[3] + 0xc1bdceee, 22); 47 MD5STEP(F1, a, b, c, d, in[4] + 0xf57c0faf, 7); 48 MD5STEP(F1, d, a, b, c, in[5] + 0x4787c62a, 12); 49 MD5STEP(F1, c, d, a, b, in[6] + 0xa8304613, 17); 50 MD5STEP(F1, b, c, d, a, in[7] + 0xfd469501, 22); 51 MD5STEP(F1, a, b, c, d, in[8] + 0x698098d8, 7); 52 MD5STEP(F1, d, a, b, c, in[9] + 0x8b44f7af, 12); 53 MD5STEP(F1, c, d, a, b, in[10] + 0xffff5bb1, 17); 54 MD5STEP(F1, b, c, d, a, in[11] + 0x895cd7be, 22); 55 MD5STEP(F1, a, b, c, d, in[12] + 0x6b901122, 7); 56 MD5STEP(F1, d, a, b, c, in[13] + 0xfd987193, 12); 57 MD5STEP(F1, c, d, a, b, in[14] + 0xa679438e, 17); 58 MD5STEP(F1, b, c, d, a, in[15] + 0x49b40821, 22); 59 60 MD5STEP(F2, a, b, c, d, in[1] + 0xf61e2562, 5); 61 MD5STEP(F2, d, a, b, c, in[6] + 0xc040b340, 9); 62 MD5STEP(F2, c, d, a, b, in[11] + 0x265e5a51, 14); 63 MD5STEP(F2, b, c, d, a, in[0] + 0xe9b6c7aa, 20); 64 MD5STEP(F2, a, b, c, d, in[5] + 0xd62f105d, 5); 65 MD5STEP(F2, d, a, b, c, in[10] + 0x02441453, 9); 66 MD5STEP(F2, c, d, a, b, in[15] + 0xd8a1e681, 14); 67 MD5STEP(F2, b, c, d, a, in[4] + 0xe7d3fbc8, 20); 68 MD5STEP(F2, a, b, c, d, in[9] + 0x21e1cde6, 5); 69 MD5STEP(F2, d, a, b, c, in[14] + 0xc33707d6, 9); 70 MD5STEP(F2, c, d, a, b, in[3] + 0xf4d50d87, 14); 71 MD5STEP(F2, b, c, d, a, in[8] + 0x455a14ed, 20); 72 MD5STEP(F2, a, b, c, d, in[13] + 0xa9e3e905, 5); 73 MD5STEP(F2, d, a, b, c, in[2] + 0xfcefa3f8, 9); 74 MD5STEP(F2, c, d, a, b, in[7] + 0x676f02d9, 14); 75 MD5STEP(F2, b, c, d, a, in[12] + 0x8d2a4c8a, 20); 76 77 MD5STEP(F3, a, b, c, d, in[5] + 0xfffa3942, 4); 78 MD5STEP(F3, d, a, b, c, in[8] + 0x8771f681, 11); 79 MD5STEP(F3, c, d, a, b, in[11] + 0x6d9d6122, 16); 80 MD5STEP(F3, b, c, d, a, in[14] + 0xfde5380c, 23); 81 MD5STEP(F3, a, b, c, d, in[1] + 0xa4beea44, 4); 82 MD5STEP(F3, d, a, b, c, in[4] + 0x4bdecfa9, 11); 83 MD5STEP(F3, c, d, a, b, in[7] + 0xf6bb4b60, 16); 84 MD5STEP(F3, b, c, d, a, in[10] + 0xbebfbc70, 23); 85 MD5STEP(F3, a, b, c, d, in[13] + 0x289b7ec6, 4); 86 MD5STEP(F3, d, a, b, c, in[0] + 0xeaa127fa, 11); 87 MD5STEP(F3, c, d, a, b, in[3] + 0xd4ef3085, 16); 88 MD5STEP(F3, b, c, d, a, in[6] + 0x04881d05, 23); 89 MD5STEP(F3, a, b, c, d, in[9] + 0xd9d4d039, 4); 90 MD5STEP(F3, d, a, b, c, in[12] + 0xe6db99e5, 11); 91 MD5STEP(F3, c, d, a, b, in[15] + 0x1fa27cf8, 16); 92 MD5STEP(F3, b, c, d, a, in[2] + 0xc4ac5665, 23); 93 94 MD5STEP(F4, a, b, c, d, in[0] + 0xf4292244, 6); 95 MD5STEP(F4, d, a, b, c, in[7] + 0x432aff97, 10); 96 MD5STEP(F4, c, d, a, b, in[14] + 0xab9423a7, 15); 97 MD5STEP(F4, b, c, d, a, in[5] + 0xfc93a039, 21); 98 MD5STEP(F4, a, b, c, d, in[12] + 0x655b59c3, 6); 99 MD5STEP(F4, d, a, b, c, in[3] + 0x8f0ccc92, 10); 100 MD5STEP(F4, c, d, a, b, in[10] + 0xffeff47d, 15); 101 MD5STEP(F4, b, c, d, a, in[1] + 0x85845dd1, 21); 102 MD5STEP(F4, a, b, c, d, in[8] + 0x6fa87e4f, 6); 103 MD5STEP(F4, d, a, b, c, in[15] + 0xfe2ce6e0, 10); 104 MD5STEP(F4, c, d, a, b, in[6] + 0xa3014314, 15); 105 MD5STEP(F4, b, c, d, a, in[13] + 0x4e0811a1, 21); 106 MD5STEP(F4, a, b, c, d, in[4] + 0xf7537e82, 6); 107 MD5STEP(F4, d, a, b, c, in[11] + 0xbd3af235, 10); 108 MD5STEP(F4, c, d, a, b, in[2] + 0x2ad7d2bb, 15); 109 MD5STEP(F4, b, c, d, a, in[9] + 0xeb86d391, 21); 110 111 hash[0] += a; 112 hash[1] += b; 113 hash[2] += c; 114 hash[3] += d; 115 } 116 117 /* XXX: this stuff can be optimized */ 118 static inline void le32_to_cpu_array(u32 *buf, unsigned int words) 119 { 120 while (words--) { 121 __le32_to_cpus(buf); 122 buf++; 123 } 124 } 125 126 static inline void cpu_to_le32_array(u32 *buf, unsigned int words) 127 { 128 while (words--) { 129 __cpu_to_le32s(buf); 130 buf++; 131 } 132 } 133 134 static inline void md5_transform_helper(struct md5_state *ctx) 135 { 136 le32_to_cpu_array(ctx->block, sizeof(ctx->block) / sizeof(u32)); 137 md5_transform(ctx->hash, ctx->block); 138 } 139 140 static int md5_init(struct shash_desc *desc) 141 { 142 struct md5_state *mctx = shash_desc_ctx(desc); 143 144 mctx->hash[0] = 0x67452301; 145 mctx->hash[1] = 0xefcdab89; 146 mctx->hash[2] = 0x98badcfe; 147 mctx->hash[3] = 0x10325476; 148 mctx->byte_count = 0; 149 150 return 0; 151 } 152 153 static int md5_update(struct shash_desc *desc, const u8 *data, unsigned int len) 154 { 155 struct md5_state *mctx = shash_desc_ctx(desc); 156 const u32 avail = sizeof(mctx->block) - (mctx->byte_count & 0x3f); 157 158 mctx->byte_count += len; 159 160 if (avail > len) { 161 memcpy((char *)mctx->block + (sizeof(mctx->block) - avail), 162 data, len); 163 return 0; 164 } 165 166 memcpy((char *)mctx->block + (sizeof(mctx->block) - avail), 167 data, avail); 168 169 md5_transform_helper(mctx); 170 data += avail; 171 len -= avail; 172 173 while (len >= sizeof(mctx->block)) { 174 memcpy(mctx->block, data, sizeof(mctx->block)); 175 md5_transform_helper(mctx); 176 data += sizeof(mctx->block); 177 len -= sizeof(mctx->block); 178 } 179 180 memcpy(mctx->block, data, len); 181 182 return 0; 183 } 184 185 static int md5_final(struct shash_desc *desc, u8 *out) 186 { 187 struct md5_state *mctx = shash_desc_ctx(desc); 188 const unsigned int offset = mctx->byte_count & 0x3f; 189 char *p = (char *)mctx->block + offset; 190 int padding = 56 - (offset + 1); 191 192 *p++ = 0x80; 193 if (padding < 0) { 194 memset(p, 0x00, padding + sizeof (u64)); 195 md5_transform_helper(mctx); 196 p = (char *)mctx->block; 197 padding = 56; 198 } 199 200 memset(p, 0, padding); 201 mctx->block[14] = mctx->byte_count << 3; 202 mctx->block[15] = mctx->byte_count >> 29; 203 le32_to_cpu_array(mctx->block, (sizeof(mctx->block) - 204 sizeof(u64)) / sizeof(u32)); 205 md5_transform(mctx->hash, mctx->block); 206 cpu_to_le32_array(mctx->hash, sizeof(mctx->hash) / sizeof(u32)); 207 memcpy(out, mctx->hash, sizeof(mctx->hash)); 208 memset(mctx, 0, sizeof(*mctx)); 209 210 return 0; 211 } 212 213 static int md5_export(struct shash_desc *desc, void *out) 214 { 215 struct md5_state *ctx = shash_desc_ctx(desc); 216 217 memcpy(out, ctx, sizeof(*ctx)); 218 return 0; 219 } 220 221 static int md5_import(struct shash_desc *desc, const void *in) 222 { 223 struct md5_state *ctx = shash_desc_ctx(desc); 224 225 memcpy(ctx, in, sizeof(*ctx)); 226 return 0; 227 } 228 229 static struct shash_alg alg = { 230 .digestsize = MD5_DIGEST_SIZE, 231 .init = md5_init, 232 .update = md5_update, 233 .final = md5_final, 234 .export = md5_export, 235 .import = md5_import, 236 .descsize = sizeof(struct md5_state), 237 .statesize = sizeof(struct md5_state), 238 .base = { 239 .cra_name = "md5", 240 .cra_flags = CRYPTO_ALG_TYPE_SHASH, 241 .cra_blocksize = MD5_HMAC_BLOCK_SIZE, 242 .cra_module = THIS_MODULE, 243 } 244 }; 245 246 static int __init md5_mod_init(void) 247 { 248 return crypto_register_shash(&alg); 249 } 250 251 static void __exit md5_mod_fini(void) 252 { 253 crypto_unregister_shash(&alg); 254 } 255 256 module_init(md5_mod_init); 257 module_exit(md5_mod_fini); 258 259 MODULE_LICENSE("GPL"); 260 MODULE_DESCRIPTION("MD5 Message Digest Algorithm"); 261