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 <linux/types.h> 28 #include <asm/byteorder.h> 29 30 #define MD4_DIGEST_SIZE 16 31 #define MD4_HMAC_BLOCK_SIZE 64 32 #define MD4_BLOCK_WORDS 16 33 #define MD4_HASH_WORDS 4 34 35 struct md4_ctx { 36 u32 hash[MD4_HASH_WORDS]; 37 u32 block[MD4_BLOCK_WORDS]; 38 u64 byte_count; 39 }; 40 41 static inline u32 lshift(u32 x, unsigned int s) 42 { 43 x &= 0xFFFFFFFF; 44 return ((x << s) & 0xFFFFFFFF) | (x >> (32 - s)); 45 } 46 47 static inline u32 F(u32 x, u32 y, u32 z) 48 { 49 return (x & y) | ((~x) & z); 50 } 51 52 static inline u32 G(u32 x, u32 y, u32 z) 53 { 54 return (x & y) | (x & z) | (y & z); 55 } 56 57 static inline u32 H(u32 x, u32 y, u32 z) 58 { 59 return x ^ y ^ z; 60 } 61 62 #define ROUND1(a,b,c,d,k,s) (a = lshift(a + F(b,c,d) + k, s)) 63 #define ROUND2(a,b,c,d,k,s) (a = lshift(a + G(b,c,d) + k + (u32)0x5A827999,s)) 64 #define ROUND3(a,b,c,d,k,s) (a = lshift(a + H(b,c,d) + k + (u32)0x6ED9EBA1,s)) 65 66 /* XXX: this stuff can be optimized */ 67 static inline void le32_to_cpu_array(u32 *buf, unsigned int words) 68 { 69 while (words--) { 70 __le32_to_cpus(buf); 71 buf++; 72 } 73 } 74 75 static inline void cpu_to_le32_array(u32 *buf, unsigned int words) 76 { 77 while (words--) { 78 __cpu_to_le32s(buf); 79 buf++; 80 } 81 } 82 83 static void md4_transform(u32 *hash, u32 const *in) 84 { 85 u32 a, b, c, d; 86 87 a = hash[0]; 88 b = hash[1]; 89 c = hash[2]; 90 d = hash[3]; 91 92 ROUND1(a, b, c, d, in[0], 3); 93 ROUND1(d, a, b, c, in[1], 7); 94 ROUND1(c, d, a, b, in[2], 11); 95 ROUND1(b, c, d, a, in[3], 19); 96 ROUND1(a, b, c, d, in[4], 3); 97 ROUND1(d, a, b, c, in[5], 7); 98 ROUND1(c, d, a, b, in[6], 11); 99 ROUND1(b, c, d, a, in[7], 19); 100 ROUND1(a, b, c, d, in[8], 3); 101 ROUND1(d, a, b, c, in[9], 7); 102 ROUND1(c, d, a, b, in[10], 11); 103 ROUND1(b, c, d, a, in[11], 19); 104 ROUND1(a, b, c, d, in[12], 3); 105 ROUND1(d, a, b, c, in[13], 7); 106 ROUND1(c, d, a, b, in[14], 11); 107 ROUND1(b, c, d, a, in[15], 19); 108 109 ROUND2(a, b, c, d,in[ 0], 3); 110 ROUND2(d, a, b, c, in[4], 5); 111 ROUND2(c, d, a, b, in[8], 9); 112 ROUND2(b, c, d, a, in[12], 13); 113 ROUND2(a, b, c, d, in[1], 3); 114 ROUND2(d, a, b, c, in[5], 5); 115 ROUND2(c, d, a, b, in[9], 9); 116 ROUND2(b, c, d, a, in[13], 13); 117 ROUND2(a, b, c, d, in[2], 3); 118 ROUND2(d, a, b, c, in[6], 5); 119 ROUND2(c, d, a, b, in[10], 9); 120 ROUND2(b, c, d, a, in[14], 13); 121 ROUND2(a, b, c, d, in[3], 3); 122 ROUND2(d, a, b, c, in[7], 5); 123 ROUND2(c, d, a, b, in[11], 9); 124 ROUND2(b, c, d, a, in[15], 13); 125 126 ROUND3(a, b, c, d,in[ 0], 3); 127 ROUND3(d, a, b, c, in[8], 9); 128 ROUND3(c, d, a, b, in[4], 11); 129 ROUND3(b, c, d, a, in[12], 15); 130 ROUND3(a, b, c, d, in[2], 3); 131 ROUND3(d, a, b, c, in[10], 9); 132 ROUND3(c, d, a, b, in[6], 11); 133 ROUND3(b, c, d, a, in[14], 15); 134 ROUND3(a, b, c, d, in[1], 3); 135 ROUND3(d, a, b, c, in[9], 9); 136 ROUND3(c, d, a, b, in[5], 11); 137 ROUND3(b, c, d, a, in[13], 15); 138 ROUND3(a, b, c, d, in[3], 3); 139 ROUND3(d, a, b, c, in[11], 9); 140 ROUND3(c, d, a, b, in[7], 11); 141 ROUND3(b, c, d, a, in[15], 15); 142 143 hash[0] += a; 144 hash[1] += b; 145 hash[2] += c; 146 hash[3] += d; 147 } 148 149 static inline void md4_transform_helper(struct md4_ctx *ctx) 150 { 151 le32_to_cpu_array(ctx->block, sizeof(ctx->block) / sizeof(u32)); 152 md4_transform(ctx->hash, ctx->block); 153 } 154 155 static void md4_init(struct crypto_tfm *tfm) 156 { 157 struct md4_ctx *mctx = crypto_tfm_ctx(tfm); 158 159 mctx->hash[0] = 0x67452301; 160 mctx->hash[1] = 0xefcdab89; 161 mctx->hash[2] = 0x98badcfe; 162 mctx->hash[3] = 0x10325476; 163 mctx->byte_count = 0; 164 } 165 166 static void md4_update(struct crypto_tfm *tfm, const u8 *data, unsigned int len) 167 { 168 struct md4_ctx *mctx = crypto_tfm_ctx(tfm); 169 const u32 avail = sizeof(mctx->block) - (mctx->byte_count & 0x3f); 170 171 mctx->byte_count += len; 172 173 if (avail > len) { 174 memcpy((char *)mctx->block + (sizeof(mctx->block) - avail), 175 data, len); 176 return; 177 } 178 179 memcpy((char *)mctx->block + (sizeof(mctx->block) - avail), 180 data, avail); 181 182 md4_transform_helper(mctx); 183 data += avail; 184 len -= avail; 185 186 while (len >= sizeof(mctx->block)) { 187 memcpy(mctx->block, data, sizeof(mctx->block)); 188 md4_transform_helper(mctx); 189 data += sizeof(mctx->block); 190 len -= sizeof(mctx->block); 191 } 192 193 memcpy(mctx->block, data, len); 194 } 195 196 static void md4_final(struct crypto_tfm *tfm, u8 *out) 197 { 198 struct md4_ctx *mctx = crypto_tfm_ctx(tfm); 199 const unsigned int offset = mctx->byte_count & 0x3f; 200 char *p = (char *)mctx->block + offset; 201 int padding = 56 - (offset + 1); 202 203 *p++ = 0x80; 204 if (padding < 0) { 205 memset(p, 0x00, padding + sizeof (u64)); 206 md4_transform_helper(mctx); 207 p = (char *)mctx->block; 208 padding = 56; 209 } 210 211 memset(p, 0, padding); 212 mctx->block[14] = mctx->byte_count << 3; 213 mctx->block[15] = mctx->byte_count >> 29; 214 le32_to_cpu_array(mctx->block, (sizeof(mctx->block) - 215 sizeof(u64)) / sizeof(u32)); 216 md4_transform(mctx->hash, mctx->block); 217 cpu_to_le32_array(mctx->hash, sizeof(mctx->hash) / sizeof(u32)); 218 memcpy(out, mctx->hash, sizeof(mctx->hash)); 219 memset(mctx, 0, sizeof(*mctx)); 220 } 221 222 static struct crypto_alg alg = { 223 .cra_name = "md4", 224 .cra_flags = CRYPTO_ALG_TYPE_DIGEST, 225 .cra_blocksize = MD4_HMAC_BLOCK_SIZE, 226 .cra_ctxsize = sizeof(struct md4_ctx), 227 .cra_module = THIS_MODULE, 228 .cra_list = LIST_HEAD_INIT(alg.cra_list), 229 .cra_u = { .digest = { 230 .dia_digestsize = MD4_DIGEST_SIZE, 231 .dia_init = md4_init, 232 .dia_update = md4_update, 233 .dia_final = md4_final } } 234 }; 235 236 static int __init md4_mod_init(void) 237 { 238 return crypto_register_alg(&alg); 239 } 240 241 static void __exit md4_mod_fini(void) 242 { 243 crypto_unregister_alg(&alg); 244 } 245 246 module_init(md4_mod_init); 247 module_exit(md4_mod_fini); 248 249 MODULE_LICENSE("GPL"); 250 MODULE_DESCRIPTION("MD4 Message Digest Algorithm"); 251 252