sha256-internal.c revision 8d520ff1dc2da35cdca849e982051b86468016d8
1/* 2 * SHA-256 hash implementation and interface functions 3 * Copyright (c) 2003-2007, 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 21struct sha256_state { 22 u64 length; 23 u32 state[8], curlen; 24 u8 buf[64]; 25}; 26 27static void sha256_init(struct sha256_state *md); 28static int sha256_process(struct sha256_state *md, const unsigned char *in, 29 unsigned long inlen); 30static int sha256_done(struct sha256_state *md, unsigned char *out); 31 32 33/** 34 * sha256_vector - SHA256 hash for data vector 35 * @num_elem: Number of elements in the data vector 36 * @addr: Pointers to the data areas 37 * @len: Lengths of the data blocks 38 * @mac: Buffer for the hash 39 * Returns: 0 on success, -1 of failure 40 */ 41int sha256_vector(size_t num_elem, const u8 *addr[], const size_t *len, 42 u8 *mac) 43{ 44 struct sha256_state ctx; 45 size_t i; 46 47 sha256_init(&ctx); 48 for (i = 0; i < num_elem; i++) 49 if (sha256_process(&ctx, addr[i], len[i])) 50 return -1; 51 if (sha256_done(&ctx, mac)) 52 return -1; 53 return 0; 54} 55 56 57/* ===== start - public domain SHA256 implementation ===== */ 58 59/* This is based on SHA256 implementation in LibTomCrypt that was released into 60 * public domain by Tom St Denis. */ 61 62/* the K array */ 63static const unsigned long K[64] = { 64 0x428a2f98UL, 0x71374491UL, 0xb5c0fbcfUL, 0xe9b5dba5UL, 0x3956c25bUL, 65 0x59f111f1UL, 0x923f82a4UL, 0xab1c5ed5UL, 0xd807aa98UL, 0x12835b01UL, 66 0x243185beUL, 0x550c7dc3UL, 0x72be5d74UL, 0x80deb1feUL, 0x9bdc06a7UL, 67 0xc19bf174UL, 0xe49b69c1UL, 0xefbe4786UL, 0x0fc19dc6UL, 0x240ca1ccUL, 68 0x2de92c6fUL, 0x4a7484aaUL, 0x5cb0a9dcUL, 0x76f988daUL, 0x983e5152UL, 69 0xa831c66dUL, 0xb00327c8UL, 0xbf597fc7UL, 0xc6e00bf3UL, 0xd5a79147UL, 70 0x06ca6351UL, 0x14292967UL, 0x27b70a85UL, 0x2e1b2138UL, 0x4d2c6dfcUL, 71 0x53380d13UL, 0x650a7354UL, 0x766a0abbUL, 0x81c2c92eUL, 0x92722c85UL, 72 0xa2bfe8a1UL, 0xa81a664bUL, 0xc24b8b70UL, 0xc76c51a3UL, 0xd192e819UL, 73 0xd6990624UL, 0xf40e3585UL, 0x106aa070UL, 0x19a4c116UL, 0x1e376c08UL, 74 0x2748774cUL, 0x34b0bcb5UL, 0x391c0cb3UL, 0x4ed8aa4aUL, 0x5b9cca4fUL, 75 0x682e6ff3UL, 0x748f82eeUL, 0x78a5636fUL, 0x84c87814UL, 0x8cc70208UL, 76 0x90befffaUL, 0xa4506cebUL, 0xbef9a3f7UL, 0xc67178f2UL 77}; 78 79 80/* Various logical functions */ 81#define RORc(x, y) \ 82( ((((unsigned long) (x) & 0xFFFFFFFFUL) >> (unsigned long) ((y) & 31)) | \ 83 ((unsigned long) (x) << (unsigned long) (32 - ((y) & 31)))) & 0xFFFFFFFFUL) 84#define Ch(x,y,z) (z ^ (x & (y ^ z))) 85#define Maj(x,y,z) (((x | y) & z) | (x & y)) 86#define S(x, n) RORc((x), (n)) 87#define R(x, n) (((x)&0xFFFFFFFFUL)>>(n)) 88#define Sigma0(x) (S(x, 2) ^ S(x, 13) ^ S(x, 22)) 89#define Sigma1(x) (S(x, 6) ^ S(x, 11) ^ S(x, 25)) 90#define Gamma0(x) (S(x, 7) ^ S(x, 18) ^ R(x, 3)) 91#define Gamma1(x) (S(x, 17) ^ S(x, 19) ^ R(x, 10)) 92#ifndef MIN 93#define MIN(x, y) (((x) < (y)) ? (x) : (y)) 94#endif 95 96/* compress 512-bits */ 97static int sha256_compress(struct sha256_state *md, unsigned char *buf) 98{ 99 u32 S[8], W[64], t0, t1; 100 u32 t; 101 int i; 102 103 /* copy state into S */ 104 for (i = 0; i < 8; i++) { 105 S[i] = md->state[i]; 106 } 107 108 /* copy the state into 512-bits into W[0..15] */ 109 for (i = 0; i < 16; i++) 110 W[i] = WPA_GET_BE32(buf + (4 * i)); 111 112 /* fill W[16..63] */ 113 for (i = 16; i < 64; i++) { 114 W[i] = Gamma1(W[i - 2]) + W[i - 7] + Gamma0(W[i - 15]) + 115 W[i - 16]; 116 } 117 118 /* Compress */ 119#define RND(a,b,c,d,e,f,g,h,i) \ 120 t0 = h + Sigma1(e) + Ch(e, f, g) + K[i] + W[i]; \ 121 t1 = Sigma0(a) + Maj(a, b, c); \ 122 d += t0; \ 123 h = t0 + t1; 124 125 for (i = 0; i < 64; ++i) { 126 RND(S[0], S[1], S[2], S[3], S[4], S[5], S[6], S[7], i); 127 t = S[7]; S[7] = S[6]; S[6] = S[5]; S[5] = S[4]; 128 S[4] = S[3]; S[3] = S[2]; S[2] = S[1]; S[1] = S[0]; S[0] = t; 129 } 130 131 /* feedback */ 132 for (i = 0; i < 8; i++) { 133 md->state[i] = md->state[i] + S[i]; 134 } 135 return 0; 136} 137 138 139/* Initialize the hash state */ 140static void sha256_init(struct sha256_state *md) 141{ 142 md->curlen = 0; 143 md->length = 0; 144 md->state[0] = 0x6A09E667UL; 145 md->state[1] = 0xBB67AE85UL; 146 md->state[2] = 0x3C6EF372UL; 147 md->state[3] = 0xA54FF53AUL; 148 md->state[4] = 0x510E527FUL; 149 md->state[5] = 0x9B05688CUL; 150 md->state[6] = 0x1F83D9ABUL; 151 md->state[7] = 0x5BE0CD19UL; 152} 153 154/** 155 Process a block of memory though the hash 156 @param md The hash state 157 @param in The data to hash 158 @param inlen The length of the data (octets) 159 @return CRYPT_OK if successful 160*/ 161static int sha256_process(struct sha256_state *md, const unsigned char *in, 162 unsigned long inlen) 163{ 164 unsigned long n; 165#define block_size 64 166 167 if (md->curlen > sizeof(md->buf)) 168 return -1; 169 170 while (inlen > 0) { 171 if (md->curlen == 0 && inlen >= block_size) { 172 if (sha256_compress(md, (unsigned char *) in) < 0) 173 return -1; 174 md->length += block_size * 8; 175 in += block_size; 176 inlen -= block_size; 177 } else { 178 n = MIN(inlen, (block_size - md->curlen)); 179 os_memcpy(md->buf + md->curlen, in, n); 180 md->curlen += n; 181 in += n; 182 inlen -= n; 183 if (md->curlen == block_size) { 184 if (sha256_compress(md, md->buf) < 0) 185 return -1; 186 md->length += 8 * block_size; 187 md->curlen = 0; 188 } 189 } 190 } 191 192 return 0; 193} 194 195 196/** 197 Terminate the hash to get the digest 198 @param md The hash state 199 @param out [out] The destination of the hash (32 bytes) 200 @return CRYPT_OK if successful 201*/ 202static int sha256_done(struct sha256_state *md, unsigned char *out) 203{ 204 int i; 205 206 if (md->curlen >= sizeof(md->buf)) 207 return -1; 208 209 /* increase the length of the message */ 210 md->length += md->curlen * 8; 211 212 /* append the '1' bit */ 213 md->buf[md->curlen++] = (unsigned char) 0x80; 214 215 /* if the length is currently above 56 bytes we append zeros 216 * then compress. Then we can fall back to padding zeros and length 217 * encoding like normal. 218 */ 219 if (md->curlen > 56) { 220 while (md->curlen < 64) { 221 md->buf[md->curlen++] = (unsigned char) 0; 222 } 223 sha256_compress(md, md->buf); 224 md->curlen = 0; 225 } 226 227 /* pad upto 56 bytes of zeroes */ 228 while (md->curlen < 56) { 229 md->buf[md->curlen++] = (unsigned char) 0; 230 } 231 232 /* store length */ 233 WPA_PUT_BE64(md->buf + 56, md->length); 234 sha256_compress(md, md->buf); 235 236 /* copy output */ 237 for (i = 0; i < 8; i++) 238 WPA_PUT_BE32(out + (4 * i), md->state[i]); 239 240 return 0; 241} 242 243/* ===== end - public domain SHA256 implementation ===== */ 244