1 /* 2 * Cryptographic API. 3 * 4 * MD4 Message Digest Algorithm (RFC1320). 5 * 6 * Implementation derived from Andrew Tridgell and Steve French's 7 * CIFS MD4 implementation, and the cryptoapi implementation 8 * originally based on the public domain implementation written 9 * by Colin Plumb in 1993. 10 * 11 * Copyright (c) Andrew Tridgell 1997-1998. 12 * Modified by Steve French (sfrench@us.ibm.com) 2002 13 * Copyright (c) Cryptoapi developers. 14 * Copyright (c) 2002 David S. Miller (davem@redhat.com) 15 * Copyright (c) 2002 James Morris <jmorris@intercode.com.au> 16 * 17 * This program is free software; you can redistribute it and/or modify 18 * it under the terms of the GNU General Public License as published by 19 * the Free Software Foundation; either version 2 of the License, or 20 * (at your option) any later version. 21 * 22 */ 23 #include <crypto/internal/hash.h> 24 #include <linux/init.h> 25 #include <linux/kernel.h> 26 #include <linux/module.h> 27 #include <linux/string.h> 28 #include <linux/types.h> 29 #include <asm/byteorder.h> 30 31 #define MD4_DIGEST_SIZE 16 32 #define MD4_HMAC_BLOCK_SIZE 64 33 #define MD4_BLOCK_WORDS 16 34 #define MD4_HASH_WORDS 4 35 36 struct md4_ctx { 37 u32 hash[MD4_HASH_WORDS]; 38 u32 block[MD4_BLOCK_WORDS]; 39 u64 byte_count; 40 }; 41 42 static inline u32 lshift(u32 x, unsigned int s) 43 { 44 x &= 0xFFFFFFFF; 45 return ((x << s) & 0xFFFFFFFF) | (x >> (32 - s)); 46 } 47 48 static inline u32 F(u32 x, u32 y, u32 z) 49 { 50 return (x & y) | ((~x) & z); 51 } 52 53 static inline u32 G(u32 x, u32 y, u32 z) 54 { 55 return (x & y) | (x & z) | (y & z); 56 } 57 58 static inline u32 H(u32 x, u32 y, u32 z) 59 { 60 return x ^ y ^ z; 61 } 62 63 #define ROUND1(a,b,c,d,k,s) (a = lshift(a + F(b,c,d) + k, s)) 64 #define ROUND2(a,b,c,d,k,s) (a = lshift(a + G(b,c,d) + k + (u32)0x5A827999,s)) 65 #define ROUND3(a,b,c,d,k,s) (a = lshift(a + H(b,c,d) + k + (u32)0x6ED9EBA1,s)) 66 67 /* XXX: this stuff can be optimized */ 68 static inline void le32_to_cpu_array(u32 *buf, unsigned int words) 69 { 70 while (words--) { 71 __le32_to_cpus(buf); 72 buf++; 73 } 74 } 75 76 static inline void cpu_to_le32_array(u32 *buf, unsigned int words) 77 { 78 while (words--) { 79 __cpu_to_le32s(buf); 80 buf++; 81 } 82 } 83 84 static void md4_transform(u32 *hash, u32 const *in) 85 { 86 u32 a, b, c, d; 87 88 a = hash[0]; 89 b = hash[1]; 90 c = hash[2]; 91 d = hash[3]; 92 93 ROUND1(a, b, c, d, in[0], 3); 94 ROUND1(d, a, b, c, in[1], 7); 95 ROUND1(c, d, a, b, in[2], 11); 96 ROUND1(b, c, d, a, in[3], 19); 97 ROUND1(a, b, c, d, in[4], 3); 98 ROUND1(d, a, b, c, in[5], 7); 99 ROUND1(c, d, a, b, in[6], 11); 100 ROUND1(b, c, d, a, in[7], 19); 101 ROUND1(a, b, c, d, in[8], 3); 102 ROUND1(d, a, b, c, in[9], 7); 103 ROUND1(c, d, a, b, in[10], 11); 104 ROUND1(b, c, d, a, in[11], 19); 105 ROUND1(a, b, c, d, in[12], 3); 106 ROUND1(d, a, b, c, in[13], 7); 107 ROUND1(c, d, a, b, in[14], 11); 108 ROUND1(b, c, d, a, in[15], 19); 109 110 ROUND2(a, b, c, d,in[ 0], 3); 111 ROUND2(d, a, b, c, in[4], 5); 112 ROUND2(c, d, a, b, in[8], 9); 113 ROUND2(b, c, d, a, in[12], 13); 114 ROUND2(a, b, c, d, in[1], 3); 115 ROUND2(d, a, b, c, in[5], 5); 116 ROUND2(c, d, a, b, in[9], 9); 117 ROUND2(b, c, d, a, in[13], 13); 118 ROUND2(a, b, c, d, in[2], 3); 119 ROUND2(d, a, b, c, in[6], 5); 120 ROUND2(c, d, a, b, in[10], 9); 121 ROUND2(b, c, d, a, in[14], 13); 122 ROUND2(a, b, c, d, in[3], 3); 123 ROUND2(d, a, b, c, in[7], 5); 124 ROUND2(c, d, a, b, in[11], 9); 125 ROUND2(b, c, d, a, in[15], 13); 126 127 ROUND3(a, b, c, d,in[ 0], 3); 128 ROUND3(d, a, b, c, in[8], 9); 129 ROUND3(c, d, a, b, in[4], 11); 130 ROUND3(b, c, d, a, in[12], 15); 131 ROUND3(a, b, c, d, in[2], 3); 132 ROUND3(d, a, b, c, in[10], 9); 133 ROUND3(c, d, a, b, in[6], 11); 134 ROUND3(b, c, d, a, in[14], 15); 135 ROUND3(a, b, c, d, in[1], 3); 136 ROUND3(d, a, b, c, in[9], 9); 137 ROUND3(c, d, a, b, in[5], 11); 138 ROUND3(b, c, d, a, in[13], 15); 139 ROUND3(a, b, c, d, in[3], 3); 140 ROUND3(d, a, b, c, in[11], 9); 141 ROUND3(c, d, a, b, in[7], 11); 142 ROUND3(b, c, d, a, in[15], 15); 143 144 hash[0] += a; 145 hash[1] += b; 146 hash[2] += c; 147 hash[3] += d; 148 } 149 150 static inline void md4_transform_helper(struct md4_ctx *ctx) 151 { 152 le32_to_cpu_array(ctx->block, ARRAY_SIZE(ctx->block)); 153 md4_transform(ctx->hash, ctx->block); 154 } 155 156 static int md4_init(struct shash_desc *desc) 157 { 158 struct md4_ctx *mctx = shash_desc_ctx(desc); 159 160 mctx->hash[0] = 0x67452301; 161 mctx->hash[1] = 0xefcdab89; 162 mctx->hash[2] = 0x98badcfe; 163 mctx->hash[3] = 0x10325476; 164 mctx->byte_count = 0; 165 166 return 0; 167 } 168 169 static int md4_update(struct shash_desc *desc, const u8 *data, unsigned int len) 170 { 171 struct md4_ctx *mctx = shash_desc_ctx(desc); 172 const u32 avail = sizeof(mctx->block) - (mctx->byte_count & 0x3f); 173 174 mctx->byte_count += len; 175 176 if (avail > len) { 177 memcpy((char *)mctx->block + (sizeof(mctx->block) - avail), 178 data, len); 179 return 0; 180 } 181 182 memcpy((char *)mctx->block + (sizeof(mctx->block) - avail), 183 data, avail); 184 185 md4_transform_helper(mctx); 186 data += avail; 187 len -= avail; 188 189 while (len >= sizeof(mctx->block)) { 190 memcpy(mctx->block, data, sizeof(mctx->block)); 191 md4_transform_helper(mctx); 192 data += sizeof(mctx->block); 193 len -= sizeof(mctx->block); 194 } 195 196 memcpy(mctx->block, data, len); 197 198 return 0; 199 } 200 201 static int md4_final(struct shash_desc *desc, u8 *out) 202 { 203 struct md4_ctx *mctx = shash_desc_ctx(desc); 204 const unsigned int offset = mctx->byte_count & 0x3f; 205 char *p = (char *)mctx->block + offset; 206 int padding = 56 - (offset + 1); 207 208 *p++ = 0x80; 209 if (padding < 0) { 210 memset(p, 0x00, padding + sizeof (u64)); 211 md4_transform_helper(mctx); 212 p = (char *)mctx->block; 213 padding = 56; 214 } 215 216 memset(p, 0, padding); 217 mctx->block[14] = mctx->byte_count << 3; 218 mctx->block[15] = mctx->byte_count >> 29; 219 le32_to_cpu_array(mctx->block, (sizeof(mctx->block) - 220 sizeof(u64)) / sizeof(u32)); 221 md4_transform(mctx->hash, mctx->block); 222 cpu_to_le32_array(mctx->hash, ARRAY_SIZE(mctx->hash)); 223 memcpy(out, mctx->hash, sizeof(mctx->hash)); 224 memset(mctx, 0, sizeof(*mctx)); 225 226 return 0; 227 } 228 229 static struct shash_alg alg = { 230 .digestsize = MD4_DIGEST_SIZE, 231 .init = md4_init, 232 .update = md4_update, 233 .final = md4_final, 234 .descsize = sizeof(struct md4_ctx), 235 .base = { 236 .cra_name = "md4", 237 .cra_flags = CRYPTO_ALG_TYPE_SHASH, 238 .cra_blocksize = MD4_HMAC_BLOCK_SIZE, 239 .cra_module = THIS_MODULE, 240 } 241 }; 242 243 static int __init md4_mod_init(void) 244 { 245 return crypto_register_shash(&alg); 246 } 247 248 static void __exit md4_mod_fini(void) 249 { 250 crypto_unregister_shash(&alg); 251 } 252 253 module_init(md4_mod_init); 254 module_exit(md4_mod_fini); 255 256 MODULE_LICENSE("GPL"); 257 MODULE_DESCRIPTION("MD4 Message Digest Algorithm"); 258 259