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 const u8 md5_zero_message_hash[MD5_DIGEST_SIZE] = { 27 0xd4, 0x1d, 0x8c, 0xd9, 0x8f, 0x00, 0xb2, 0x04, 28 0xe9, 0x80, 0x09, 0x98, 0xec, 0xf8, 0x42, 0x7e, 29 }; 30 EXPORT_SYMBOL_GPL(md5_zero_message_hash); 31 32 #define F1(x, y, z) (z ^ (x & (y ^ z))) 33 #define F2(x, y, z) F1(z, x, y) 34 #define F3(x, y, z) (x ^ y ^ z) 35 #define F4(x, y, z) (y ^ (x | ~z)) 36 37 #define MD5STEP(f, w, x, y, z, in, s) \ 38 (w += f(x, y, z) + in, w = (w<<s | w>>(32-s)) + x) 39 40 static void md5_transform(__u32 *hash, __u32 const *in) 41 { 42 u32 a, b, c, d; 43 44 a = hash[0]; 45 b = hash[1]; 46 c = hash[2]; 47 d = hash[3]; 48 49 MD5STEP(F1, a, b, c, d, in[0] + 0xd76aa478, 7); 50 MD5STEP(F1, d, a, b, c, in[1] + 0xe8c7b756, 12); 51 MD5STEP(F1, c, d, a, b, in[2] + 0x242070db, 17); 52 MD5STEP(F1, b, c, d, a, in[3] + 0xc1bdceee, 22); 53 MD5STEP(F1, a, b, c, d, in[4] + 0xf57c0faf, 7); 54 MD5STEP(F1, d, a, b, c, in[5] + 0x4787c62a, 12); 55 MD5STEP(F1, c, d, a, b, in[6] + 0xa8304613, 17); 56 MD5STEP(F1, b, c, d, a, in[7] + 0xfd469501, 22); 57 MD5STEP(F1, a, b, c, d, in[8] + 0x698098d8, 7); 58 MD5STEP(F1, d, a, b, c, in[9] + 0x8b44f7af, 12); 59 MD5STEP(F1, c, d, a, b, in[10] + 0xffff5bb1, 17); 60 MD5STEP(F1, b, c, d, a, in[11] + 0x895cd7be, 22); 61 MD5STEP(F1, a, b, c, d, in[12] + 0x6b901122, 7); 62 MD5STEP(F1, d, a, b, c, in[13] + 0xfd987193, 12); 63 MD5STEP(F1, c, d, a, b, in[14] + 0xa679438e, 17); 64 MD5STEP(F1, b, c, d, a, in[15] + 0x49b40821, 22); 65 66 MD5STEP(F2, a, b, c, d, in[1] + 0xf61e2562, 5); 67 MD5STEP(F2, d, a, b, c, in[6] + 0xc040b340, 9); 68 MD5STEP(F2, c, d, a, b, in[11] + 0x265e5a51, 14); 69 MD5STEP(F2, b, c, d, a, in[0] + 0xe9b6c7aa, 20); 70 MD5STEP(F2, a, b, c, d, in[5] + 0xd62f105d, 5); 71 MD5STEP(F2, d, a, b, c, in[10] + 0x02441453, 9); 72 MD5STEP(F2, c, d, a, b, in[15] + 0xd8a1e681, 14); 73 MD5STEP(F2, b, c, d, a, in[4] + 0xe7d3fbc8, 20); 74 MD5STEP(F2, a, b, c, d, in[9] + 0x21e1cde6, 5); 75 MD5STEP(F2, d, a, b, c, in[14] + 0xc33707d6, 9); 76 MD5STEP(F2, c, d, a, b, in[3] + 0xf4d50d87, 14); 77 MD5STEP(F2, b, c, d, a, in[8] + 0x455a14ed, 20); 78 MD5STEP(F2, a, b, c, d, in[13] + 0xa9e3e905, 5); 79 MD5STEP(F2, d, a, b, c, in[2] + 0xfcefa3f8, 9); 80 MD5STEP(F2, c, d, a, b, in[7] + 0x676f02d9, 14); 81 MD5STEP(F2, b, c, d, a, in[12] + 0x8d2a4c8a, 20); 82 83 MD5STEP(F3, a, b, c, d, in[5] + 0xfffa3942, 4); 84 MD5STEP(F3, d, a, b, c, in[8] + 0x8771f681, 11); 85 MD5STEP(F3, c, d, a, b, in[11] + 0x6d9d6122, 16); 86 MD5STEP(F3, b, c, d, a, in[14] + 0xfde5380c, 23); 87 MD5STEP(F3, a, b, c, d, in[1] + 0xa4beea44, 4); 88 MD5STEP(F3, d, a, b, c, in[4] + 0x4bdecfa9, 11); 89 MD5STEP(F3, c, d, a, b, in[7] + 0xf6bb4b60, 16); 90 MD5STEP(F3, b, c, d, a, in[10] + 0xbebfbc70, 23); 91 MD5STEP(F3, a, b, c, d, in[13] + 0x289b7ec6, 4); 92 MD5STEP(F3, d, a, b, c, in[0] + 0xeaa127fa, 11); 93 MD5STEP(F3, c, d, a, b, in[3] + 0xd4ef3085, 16); 94 MD5STEP(F3, b, c, d, a, in[6] + 0x04881d05, 23); 95 MD5STEP(F3, a, b, c, d, in[9] + 0xd9d4d039, 4); 96 MD5STEP(F3, d, a, b, c, in[12] + 0xe6db99e5, 11); 97 MD5STEP(F3, c, d, a, b, in[15] + 0x1fa27cf8, 16); 98 MD5STEP(F3, b, c, d, a, in[2] + 0xc4ac5665, 23); 99 100 MD5STEP(F4, a, b, c, d, in[0] + 0xf4292244, 6); 101 MD5STEP(F4, d, a, b, c, in[7] + 0x432aff97, 10); 102 MD5STEP(F4, c, d, a, b, in[14] + 0xab9423a7, 15); 103 MD5STEP(F4, b, c, d, a, in[5] + 0xfc93a039, 21); 104 MD5STEP(F4, a, b, c, d, in[12] + 0x655b59c3, 6); 105 MD5STEP(F4, d, a, b, c, in[3] + 0x8f0ccc92, 10); 106 MD5STEP(F4, c, d, a, b, in[10] + 0xffeff47d, 15); 107 MD5STEP(F4, b, c, d, a, in[1] + 0x85845dd1, 21); 108 MD5STEP(F4, a, b, c, d, in[8] + 0x6fa87e4f, 6); 109 MD5STEP(F4, d, a, b, c, in[15] + 0xfe2ce6e0, 10); 110 MD5STEP(F4, c, d, a, b, in[6] + 0xa3014314, 15); 111 MD5STEP(F4, b, c, d, a, in[13] + 0x4e0811a1, 21); 112 MD5STEP(F4, a, b, c, d, in[4] + 0xf7537e82, 6); 113 MD5STEP(F4, d, a, b, c, in[11] + 0xbd3af235, 10); 114 MD5STEP(F4, c, d, a, b, in[2] + 0x2ad7d2bb, 15); 115 MD5STEP(F4, b, c, d, a, in[9] + 0xeb86d391, 21); 116 117 hash[0] += a; 118 hash[1] += b; 119 hash[2] += c; 120 hash[3] += d; 121 } 122 123 static inline void md5_transform_helper(struct md5_state *ctx) 124 { 125 le32_to_cpu_array(ctx->block, sizeof(ctx->block) / sizeof(u32)); 126 md5_transform(ctx->hash, ctx->block); 127 } 128 129 static int md5_init(struct shash_desc *desc) 130 { 131 struct md5_state *mctx = shash_desc_ctx(desc); 132 133 mctx->hash[0] = MD5_H0; 134 mctx->hash[1] = MD5_H1; 135 mctx->hash[2] = MD5_H2; 136 mctx->hash[3] = MD5_H3; 137 mctx->byte_count = 0; 138 139 return 0; 140 } 141 142 static int md5_update(struct shash_desc *desc, const u8 *data, unsigned int len) 143 { 144 struct md5_state *mctx = shash_desc_ctx(desc); 145 const u32 avail = sizeof(mctx->block) - (mctx->byte_count & 0x3f); 146 147 mctx->byte_count += len; 148 149 if (avail > len) { 150 memcpy((char *)mctx->block + (sizeof(mctx->block) - avail), 151 data, len); 152 return 0; 153 } 154 155 memcpy((char *)mctx->block + (sizeof(mctx->block) - avail), 156 data, avail); 157 158 md5_transform_helper(mctx); 159 data += avail; 160 len -= avail; 161 162 while (len >= sizeof(mctx->block)) { 163 memcpy(mctx->block, data, sizeof(mctx->block)); 164 md5_transform_helper(mctx); 165 data += sizeof(mctx->block); 166 len -= sizeof(mctx->block); 167 } 168 169 memcpy(mctx->block, data, len); 170 171 return 0; 172 } 173 174 static int md5_final(struct shash_desc *desc, u8 *out) 175 { 176 struct md5_state *mctx = shash_desc_ctx(desc); 177 const unsigned int offset = mctx->byte_count & 0x3f; 178 char *p = (char *)mctx->block + offset; 179 int padding = 56 - (offset + 1); 180 181 *p++ = 0x80; 182 if (padding < 0) { 183 memset(p, 0x00, padding + sizeof (u64)); 184 md5_transform_helper(mctx); 185 p = (char *)mctx->block; 186 padding = 56; 187 } 188 189 memset(p, 0, padding); 190 mctx->block[14] = mctx->byte_count << 3; 191 mctx->block[15] = mctx->byte_count >> 29; 192 le32_to_cpu_array(mctx->block, (sizeof(mctx->block) - 193 sizeof(u64)) / sizeof(u32)); 194 md5_transform(mctx->hash, mctx->block); 195 cpu_to_le32_array(mctx->hash, sizeof(mctx->hash) / sizeof(u32)); 196 memcpy(out, mctx->hash, sizeof(mctx->hash)); 197 memset(mctx, 0, sizeof(*mctx)); 198 199 return 0; 200 } 201 202 static int md5_export(struct shash_desc *desc, void *out) 203 { 204 struct md5_state *ctx = shash_desc_ctx(desc); 205 206 memcpy(out, ctx, sizeof(*ctx)); 207 return 0; 208 } 209 210 static int md5_import(struct shash_desc *desc, const void *in) 211 { 212 struct md5_state *ctx = shash_desc_ctx(desc); 213 214 memcpy(ctx, in, sizeof(*ctx)); 215 return 0; 216 } 217 218 static struct shash_alg alg = { 219 .digestsize = MD5_DIGEST_SIZE, 220 .init = md5_init, 221 .update = md5_update, 222 .final = md5_final, 223 .export = md5_export, 224 .import = md5_import, 225 .descsize = sizeof(struct md5_state), 226 .statesize = sizeof(struct md5_state), 227 .base = { 228 .cra_name = "md5", 229 .cra_driver_name = "md5-generic", 230 .cra_blocksize = MD5_HMAC_BLOCK_SIZE, 231 .cra_module = THIS_MODULE, 232 } 233 }; 234 235 static int __init md5_mod_init(void) 236 { 237 return crypto_register_shash(&alg); 238 } 239 240 static void __exit md5_mod_fini(void) 241 { 242 crypto_unregister_shash(&alg); 243 } 244 245 subsys_initcall(md5_mod_init); 246 module_exit(md5_mod_fini); 247 248 MODULE_LICENSE("GPL"); 249 MODULE_DESCRIPTION("MD5 Message Digest Algorithm"); 250 MODULE_ALIAS_CRYPTO("md5"); 251