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 <linux/init.h> 24 #include <linux/crypto.h> 25 #include <linux/kernel.h> 26 #include <linux/string.h> 27 #include <asm/byteorder.h> 28 29 #define MD4_DIGEST_SIZE 16 30 #define MD4_HMAC_BLOCK_SIZE 64 31 #define MD4_BLOCK_WORDS 16 32 #define MD4_HASH_WORDS 4 33 34 struct md4_ctx { 35 u32 hash[MD4_HASH_WORDS]; 36 u32 block[MD4_BLOCK_WORDS]; 37 u64 byte_count; 38 }; 39 40 static inline u32 lshift(u32 x, unsigned int s) 41 { 42 x &= 0xFFFFFFFF; 43 return ((x << s) & 0xFFFFFFFF) | (x >> (32 - s)); 44 } 45 46 static inline u32 F(u32 x, u32 y, u32 z) 47 { 48 return (x & y) | ((~x) & z); 49 } 50 51 static inline u32 G(u32 x, u32 y, u32 z) 52 { 53 return (x & y) | (x & z) | (y & z); 54 } 55 56 static inline u32 H(u32 x, u32 y, u32 z) 57 { 58 return x ^ y ^ z; 59 } 60 61 #define ROUND1(a,b,c,d,k,s) (a = lshift(a + F(b,c,d) + k, s)) 62 #define ROUND2(a,b,c,d,k,s) (a = lshift(a + G(b,c,d) + k + (u32)0x5A827999,s)) 63 #define ROUND3(a,b,c,d,k,s) (a = lshift(a + H(b,c,d) + k + (u32)0x6ED9EBA1,s)) 64 65 /* XXX: this stuff can be optimized */ 66 static inline void le32_to_cpu_array(u32 *buf, unsigned int words) 67 { 68 while (words--) { 69 __le32_to_cpus(buf); 70 buf++; 71 } 72 } 73 74 static inline void cpu_to_le32_array(u32 *buf, unsigned int words) 75 { 76 while (words--) { 77 __cpu_to_le32s(buf); 78 buf++; 79 } 80 } 81 82 static void md4_transform(u32 *hash, u32 const *in) 83 { 84 u32 a, b, c, d; 85 86 a = hash[0]; 87 b = hash[1]; 88 c = hash[2]; 89 d = hash[3]; 90 91 ROUND1(a, b, c, d, in[0], 3); 92 ROUND1(d, a, b, c, in[1], 7); 93 ROUND1(c, d, a, b, in[2], 11); 94 ROUND1(b, c, d, a, in[3], 19); 95 ROUND1(a, b, c, d, in[4], 3); 96 ROUND1(d, a, b, c, in[5], 7); 97 ROUND1(c, d, a, b, in[6], 11); 98 ROUND1(b, c, d, a, in[7], 19); 99 ROUND1(a, b, c, d, in[8], 3); 100 ROUND1(d, a, b, c, in[9], 7); 101 ROUND1(c, d, a, b, in[10], 11); 102 ROUND1(b, c, d, a, in[11], 19); 103 ROUND1(a, b, c, d, in[12], 3); 104 ROUND1(d, a, b, c, in[13], 7); 105 ROUND1(c, d, a, b, in[14], 11); 106 ROUND1(b, c, d, a, in[15], 19); 107 108 ROUND2(a, b, c, d,in[ 0], 3); 109 ROUND2(d, a, b, c, in[4], 5); 110 ROUND2(c, d, a, b, in[8], 9); 111 ROUND2(b, c, d, a, in[12], 13); 112 ROUND2(a, b, c, d, in[1], 3); 113 ROUND2(d, a, b, c, in[5], 5); 114 ROUND2(c, d, a, b, in[9], 9); 115 ROUND2(b, c, d, a, in[13], 13); 116 ROUND2(a, b, c, d, in[2], 3); 117 ROUND2(d, a, b, c, in[6], 5); 118 ROUND2(c, d, a, b, in[10], 9); 119 ROUND2(b, c, d, a, in[14], 13); 120 ROUND2(a, b, c, d, in[3], 3); 121 ROUND2(d, a, b, c, in[7], 5); 122 ROUND2(c, d, a, b, in[11], 9); 123 ROUND2(b, c, d, a, in[15], 13); 124 125 ROUND3(a, b, c, d,in[ 0], 3); 126 ROUND3(d, a, b, c, in[8], 9); 127 ROUND3(c, d, a, b, in[4], 11); 128 ROUND3(b, c, d, a, in[12], 15); 129 ROUND3(a, b, c, d, in[2], 3); 130 ROUND3(d, a, b, c, in[10], 9); 131 ROUND3(c, d, a, b, in[6], 11); 132 ROUND3(b, c, d, a, in[14], 15); 133 ROUND3(a, b, c, d, in[1], 3); 134 ROUND3(d, a, b, c, in[9], 9); 135 ROUND3(c, d, a, b, in[5], 11); 136 ROUND3(b, c, d, a, in[13], 15); 137 ROUND3(a, b, c, d, in[3], 3); 138 ROUND3(d, a, b, c, in[11], 9); 139 ROUND3(c, d, a, b, in[7], 11); 140 ROUND3(b, c, d, a, in[15], 15); 141 142 hash[0] += a; 143 hash[1] += b; 144 hash[2] += c; 145 hash[3] += d; 146 } 147 148 static inline void md4_transform_helper(struct md4_ctx *ctx) 149 { 150 le32_to_cpu_array(ctx->block, sizeof(ctx->block) / sizeof(u32)); 151 md4_transform(ctx->hash, ctx->block); 152 } 153 154 static void md4_init(void *ctx) 155 { 156 struct md4_ctx *mctx = ctx; 157 158 mctx->hash[0] = 0x67452301; 159 mctx->hash[1] = 0xefcdab89; 160 mctx->hash[2] = 0x98badcfe; 161 mctx->hash[3] = 0x10325476; 162 mctx->byte_count = 0; 163 } 164 165 static void md4_update(void *ctx, const u8 *data, unsigned int len) 166 { 167 struct md4_ctx *mctx = ctx; 168 const u32 avail = sizeof(mctx->block) - (mctx->byte_count & 0x3f); 169 170 mctx->byte_count += len; 171 172 if (avail > len) { 173 memcpy((char *)mctx->block + (sizeof(mctx->block) - avail), 174 data, len); 175 return; 176 } 177 178 memcpy((char *)mctx->block + (sizeof(mctx->block) - avail), 179 data, avail); 180 181 md4_transform_helper(mctx); 182 data += avail; 183 len -= avail; 184 185 while (len >= sizeof(mctx->block)) { 186 memcpy(mctx->block, data, sizeof(mctx->block)); 187 md4_transform_helper(mctx); 188 data += sizeof(mctx->block); 189 len -= sizeof(mctx->block); 190 } 191 192 memcpy(mctx->block, data, len); 193 } 194 195 static void md4_final(void *ctx, u8 *out) 196 { 197 struct md4_ctx *mctx = ctx; 198 const unsigned int offset = mctx->byte_count & 0x3f; 199 char *p = (char *)mctx->block + offset; 200 int padding = 56 - (offset + 1); 201 202 *p++ = 0x80; 203 if (padding < 0) { 204 memset(p, 0x00, padding + sizeof (u64)); 205 md4_transform_helper(mctx); 206 p = (char *)mctx->block; 207 padding = 56; 208 } 209 210 memset(p, 0, padding); 211 mctx->block[14] = mctx->byte_count << 3; 212 mctx->block[15] = mctx->byte_count >> 29; 213 le32_to_cpu_array(mctx->block, (sizeof(mctx->block) - 214 sizeof(u64)) / sizeof(u32)); 215 md4_transform(mctx->hash, mctx->block); 216 cpu_to_le32_array(mctx->hash, sizeof(mctx->hash) / sizeof(u32)); 217 memcpy(out, mctx->hash, sizeof(mctx->hash)); 218 memset(mctx, 0, sizeof(*mctx)); 219 } 220 221 static struct crypto_alg alg = { 222 .cra_name = "md4", 223 .cra_flags = CRYPTO_ALG_TYPE_DIGEST, 224 .cra_blocksize = MD4_HMAC_BLOCK_SIZE, 225 .cra_ctxsize = sizeof(struct md4_ctx), 226 .cra_module = THIS_MODULE, 227 .cra_list = LIST_HEAD_INIT(alg.cra_list), 228 .cra_u = { .digest = { 229 .dia_digestsize = MD4_DIGEST_SIZE, 230 .dia_init = md4_init, 231 .dia_update = md4_update, 232 .dia_final = md4_final } } 233 }; 234 235 static int __init init(void) 236 { 237 return crypto_register_alg(&alg); 238 } 239 240 static void __exit fini(void) 241 { 242 crypto_unregister_alg(&alg); 243 } 244 245 module_init(init); 246 module_exit(fini); 247 248 MODULE_LICENSE("GPL"); 249 MODULE_DESCRIPTION("MD4 Message Digest Algorithm"); 250 251