1 /* 2 * SHA-256 hash implementation and interface functions 3 * Copyright (c) 2003-2011, Jouni Malinen <j@w1.fi> 4 * 5 * This program is free software; you can redistribute it and/or modify 6 * it under the terms of the GNU General Public License version 2 as 7 * published by the Free Software Foundation. 8 * 9 * Alternatively, this software may be distributed under the terms of BSD 10 * license. 11 * 12 * See README and COPYING for more details. 13 */ 14 15 #include "includes.h" 16 17 #include "common.h" 18 #include "sha256.h" 19 #include "crypto.h" 20 21 #define SHA256_BLOCK_SIZE 64 22 23 struct sha256_state { 24 u64 length; 25 u32 state[8], curlen; 26 u8 buf[SHA256_BLOCK_SIZE]; 27 }; 28 29 static void sha256_init(struct sha256_state *md); 30 static int sha256_process(struct sha256_state *md, const unsigned char *in, 31 unsigned long inlen); 32 static int sha256_done(struct sha256_state *md, unsigned char *out); 33 34 35 /** 36 * sha256_vector - SHA256 hash for data vector 37 * @num_elem: Number of elements in the data vector 38 * @addr: Pointers to the data areas 39 * @len: Lengths of the data blocks 40 * @mac: Buffer for the hash 41 * Returns: 0 on success, -1 of failure 42 */ 43 int sha256_vector(size_t num_elem, const u8 *addr[], const size_t *len, 44 u8 *mac) 45 { 46 struct sha256_state ctx; 47 size_t i; 48 49 sha256_init(&ctx); 50 for (i = 0; i < num_elem; i++) 51 if (sha256_process(&ctx, addr[i], len[i])) 52 return -1; 53 if (sha256_done(&ctx, mac)) 54 return -1; 55 return 0; 56 } 57 58 59 /* ===== start - public domain SHA256 implementation ===== */ 60 61 /* This is based on SHA256 implementation in LibTomCrypt that was released into 62 * public domain by Tom St Denis. */ 63 64 /* the K array */ 65 static const unsigned long K[64] = { 66 0x428a2f98UL, 0x71374491UL, 0xb5c0fbcfUL, 0xe9b5dba5UL, 0x3956c25bUL, 67 0x59f111f1UL, 0x923f82a4UL, 0xab1c5ed5UL, 0xd807aa98UL, 0x12835b01UL, 68 0x243185beUL, 0x550c7dc3UL, 0x72be5d74UL, 0x80deb1feUL, 0x9bdc06a7UL, 69 0xc19bf174UL, 0xe49b69c1UL, 0xefbe4786UL, 0x0fc19dc6UL, 0x240ca1ccUL, 70 0x2de92c6fUL, 0x4a7484aaUL, 0x5cb0a9dcUL, 0x76f988daUL, 0x983e5152UL, 71 0xa831c66dUL, 0xb00327c8UL, 0xbf597fc7UL, 0xc6e00bf3UL, 0xd5a79147UL, 72 0x06ca6351UL, 0x14292967UL, 0x27b70a85UL, 0x2e1b2138UL, 0x4d2c6dfcUL, 73 0x53380d13UL, 0x650a7354UL, 0x766a0abbUL, 0x81c2c92eUL, 0x92722c85UL, 74 0xa2bfe8a1UL, 0xa81a664bUL, 0xc24b8b70UL, 0xc76c51a3UL, 0xd192e819UL, 75 0xd6990624UL, 0xf40e3585UL, 0x106aa070UL, 0x19a4c116UL, 0x1e376c08UL, 76 0x2748774cUL, 0x34b0bcb5UL, 0x391c0cb3UL, 0x4ed8aa4aUL, 0x5b9cca4fUL, 77 0x682e6ff3UL, 0x748f82eeUL, 0x78a5636fUL, 0x84c87814UL, 0x8cc70208UL, 78 0x90befffaUL, 0xa4506cebUL, 0xbef9a3f7UL, 0xc67178f2UL 79 }; 80 81 82 /* Various logical functions */ 83 #define RORc(x, y) \ 84 ( ((((unsigned long) (x) & 0xFFFFFFFFUL) >> (unsigned long) ((y) & 31)) | \ 85 ((unsigned long) (x) << (unsigned long) (32 - ((y) & 31)))) & 0xFFFFFFFFUL) 86 #define Ch(x,y,z) (z ^ (x & (y ^ z))) 87 #define Maj(x,y,z) (((x | y) & z) | (x & y)) 88 #define S(x, n) RORc((x), (n)) 89 #define R(x, n) (((x)&0xFFFFFFFFUL)>>(n)) 90 #define Sigma0(x) (S(x, 2) ^ S(x, 13) ^ S(x, 22)) 91 #define Sigma1(x) (S(x, 6) ^ S(x, 11) ^ S(x, 25)) 92 #define Gamma0(x) (S(x, 7) ^ S(x, 18) ^ R(x, 3)) 93 #define Gamma1(x) (S(x, 17) ^ S(x, 19) ^ R(x, 10)) 94 #ifndef MIN 95 #define MIN(x, y) (((x) < (y)) ? (x) : (y)) 96 #endif 97 98 /* compress 512-bits */ 99 static int sha256_compress(struct sha256_state *md, unsigned char *buf) 100 { 101 u32 S[8], W[64], t0, t1; 102 u32 t; 103 int i; 104 105 /* copy state into S */ 106 for (i = 0; i < 8; i++) { 107 S[i] = md->state[i]; 108 } 109 110 /* copy the state into 512-bits into W[0..15] */ 111 for (i = 0; i < 16; i++) 112 W[i] = WPA_GET_BE32(buf + (4 * i)); 113 114 /* fill W[16..63] */ 115 for (i = 16; i < 64; i++) { 116 W[i] = Gamma1(W[i - 2]) + W[i - 7] + Gamma0(W[i - 15]) + 117 W[i - 16]; 118 } 119 120 /* Compress */ 121 #define RND(a,b,c,d,e,f,g,h,i) \ 122 t0 = h + Sigma1(e) + Ch(e, f, g) + K[i] + W[i]; \ 123 t1 = Sigma0(a) + Maj(a, b, c); \ 124 d += t0; \ 125 h = t0 + t1; 126 127 for (i = 0; i < 64; ++i) { 128 RND(S[0], S[1], S[2], S[3], S[4], S[5], S[6], S[7], i); 129 t = S[7]; S[7] = S[6]; S[6] = S[5]; S[5] = S[4]; 130 S[4] = S[3]; S[3] = S[2]; S[2] = S[1]; S[1] = S[0]; S[0] = t; 131 } 132 133 /* feedback */ 134 for (i = 0; i < 8; i++) { 135 md->state[i] = md->state[i] + S[i]; 136 } 137 return 0; 138 } 139 140 141 /* Initialize the hash state */ 142 static void sha256_init(struct sha256_state *md) 143 { 144 md->curlen = 0; 145 md->length = 0; 146 md->state[0] = 0x6A09E667UL; 147 md->state[1] = 0xBB67AE85UL; 148 md->state[2] = 0x3C6EF372UL; 149 md->state[3] = 0xA54FF53AUL; 150 md->state[4] = 0x510E527FUL; 151 md->state[5] = 0x9B05688CUL; 152 md->state[6] = 0x1F83D9ABUL; 153 md->state[7] = 0x5BE0CD19UL; 154 } 155 156 /** 157 Process a block of memory though the hash 158 @param md The hash state 159 @param in The data to hash 160 @param inlen The length of the data (octets) 161 @return CRYPT_OK if successful 162 */ 163 static int sha256_process(struct sha256_state *md, const unsigned char *in, 164 unsigned long inlen) 165 { 166 unsigned long n; 167 168 if (md->curlen >= sizeof(md->buf)) 169 return -1; 170 171 while (inlen > 0) { 172 if (md->curlen == 0 && inlen >= SHA256_BLOCK_SIZE) { 173 if (sha256_compress(md, (unsigned char *) in) < 0) 174 return -1; 175 md->length += SHA256_BLOCK_SIZE * 8; 176 in += SHA256_BLOCK_SIZE; 177 inlen -= SHA256_BLOCK_SIZE; 178 } else { 179 n = MIN(inlen, (SHA256_BLOCK_SIZE - md->curlen)); 180 os_memcpy(md->buf + md->curlen, in, n); 181 md->curlen += n; 182 in += n; 183 inlen -= n; 184 if (md->curlen == SHA256_BLOCK_SIZE) { 185 if (sha256_compress(md, md->buf) < 0) 186 return -1; 187 md->length += 8 * SHA256_BLOCK_SIZE; 188 md->curlen = 0; 189 } 190 } 191 } 192 193 return 0; 194 } 195 196 197 /** 198 Terminate the hash to get the digest 199 @param md The hash state 200 @param out [out] The destination of the hash (32 bytes) 201 @return CRYPT_OK if successful 202 */ 203 static int sha256_done(struct sha256_state *md, unsigned char *out) 204 { 205 int i; 206 207 if (md->curlen >= sizeof(md->buf)) 208 return -1; 209 210 /* increase the length of the message */ 211 md->length += md->curlen * 8; 212 213 /* append the '1' bit */ 214 md->buf[md->curlen++] = (unsigned char) 0x80; 215 216 /* if the length is currently above 56 bytes we append zeros 217 * then compress. Then we can fall back to padding zeros and length 218 * encoding like normal. 219 */ 220 if (md->curlen > 56) { 221 while (md->curlen < SHA256_BLOCK_SIZE) { 222 md->buf[md->curlen++] = (unsigned char) 0; 223 } 224 sha256_compress(md, md->buf); 225 md->curlen = 0; 226 } 227 228 /* pad up to 56 bytes of zeroes */ 229 while (md->curlen < 56) { 230 md->buf[md->curlen++] = (unsigned char) 0; 231 } 232 233 /* store length */ 234 WPA_PUT_BE64(md->buf + 56, md->length); 235 sha256_compress(md, md->buf); 236 237 /* copy output */ 238 for (i = 0; i < 8; i++) 239 WPA_PUT_BE32(out + (4 * i), md->state[i]); 240 241 return 0; 242 } 243 244 /* ===== end - public domain SHA256 implementation ===== */ 245