/* sha256.c - SHA224 and SHA256 hash functions * Copyright (C) 2003, 2006 Free Software Foundation, Inc. * * Please see below for more legal information! * * This file is part of GnuPG. * * GnuPG is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 3 of the License, or * (at your option) any later version. * * GnuPG is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, see . */ /* Test vectors from FIPS-180-2: * * "abc" * 224: * 23097D22 3405D822 8642A477 BDA255B3 2AADBCE4 BDA0B3F7 E36C9DA7 * 256: * BA7816BF 8F01CFEA 414140DE 5DAE2223 B00361A3 96177A9C B410FF61 F20015AD * * "abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq" * 224: * 75388B16 512776CC 5DBA5DA1 FD890150 B0C6455C B4F58B19 52522525 * 256: * 248D6A61 D20638B8 E5C02693 0C3E6039 A33CE459 64FF2167 F6ECEDD4 19DB06C1 * * "a" x 1000000 * 224: * 20794655 980C91D8 BBB4C1EA 97618A4B F03F4258 1948B2EE 4EE7AD67 * 256: * CDC76E5C 9914FB92 81A1C7E2 84D73E67 F1809A48 A497200E 046D39CC C7112CD0 */ #include #include #include "util.h" #include "algorithms.h" typedef struct { u32 h0,h1,h2,h3,h4,h5,h6,h7; u32 nblocks; byte buf[64]; int count; } SHA256_CONTEXT; static void burn_stack (int bytes) { char buf[128]; wipememory(buf,sizeof buf); bytes -= sizeof buf; if (bytes > 0) burn_stack (bytes); } void sha256_init( SHA256_CONTEXT *hd ) { hd->h0 = 0x6a09e667; hd->h1 = 0xbb67ae85; hd->h2 = 0x3c6ef372; hd->h3 = 0xa54ff53a; hd->h4 = 0x510e527f; hd->h5 = 0x9b05688c; hd->h6 = 0x1f83d9ab; hd->h7 = 0x5be0cd19; hd->nblocks = 0; hd->count = 0; } void sha224_init( SHA256_CONTEXT *hd ) { hd->h0 = 0xc1059ed8; hd->h1 = 0x367cd507; hd->h2 = 0x3070dd17; hd->h3 = 0xf70e5939; hd->h4 = 0xffc00b31; hd->h5 = 0x68581511; hd->h6 = 0x64f98fa7; hd->h7 = 0xbefa4fa4; hd->nblocks = 0; hd->count = 0; } /**************** * Transform the message w which consists of 16 32-bit words */ static void transform( SHA256_CONTEXT *hd, byte *data ) { u32 a,b,c,d,e,f,g,h; u32 w[64]; int t; static const u32 k[]= { 0x428a2f98, 0x71374491, 0xb5c0fbcf, 0xe9b5dba5, 0x3956c25b, 0x59f111f1, 0x923f82a4, 0xab1c5ed5, 0xd807aa98, 0x12835b01, 0x243185be, 0x550c7dc3, 0x72be5d74, 0x80deb1fe, 0x9bdc06a7, 0xc19bf174, 0xe49b69c1, 0xefbe4786, 0x0fc19dc6, 0x240ca1cc, 0x2de92c6f, 0x4a7484aa, 0x5cb0a9dc, 0x76f988da, 0x983e5152, 0xa831c66d, 0xb00327c8, 0xbf597fc7, 0xc6e00bf3, 0xd5a79147, 0x06ca6351, 0x14292967, 0x27b70a85, 0x2e1b2138, 0x4d2c6dfc, 0x53380d13, 0x650a7354, 0x766a0abb, 0x81c2c92e, 0x92722c85, 0xa2bfe8a1, 0xa81a664b, 0xc24b8b70, 0xc76c51a3, 0xd192e819, 0xd6990624, 0xf40e3585, 0x106aa070, 0x19a4c116, 0x1e376c08, 0x2748774c, 0x34b0bcb5, 0x391c0cb3, 0x4ed8aa4a, 0x5b9cca4f, 0x682e6ff3, 0x748f82ee, 0x78a5636f, 0x84c87814, 0x8cc70208, 0x90befffa, 0xa4506ceb, 0xbef9a3f7, 0xc67178f2 }; /* get values from the chaining vars */ a = hd->h0; b = hd->h1; c = hd->h2; d = hd->h3; e = hd->h4; f = hd->h5; g = hd->h6; h = hd->h7; #ifdef BIG_ENDIAN_HOST memcpy( w, data, 64 ); #else { int i; byte *p2; for(i=0, p2=(byte*)w; i < 16; i++, p2 += 4 ) { p2[3] = *data++; p2[2] = *data++; p2[1] = *data++; p2[0] = *data++; } } #endif #define ROTR(x,n) (((x)>>(n)) | ((x)<<(32-(n)))) #define Ch(x,y,z) (((x) & (y)) ^ ((~(x)) & (z))) #define Maj(x,y,z) (((x) & (y)) ^ ((x) & (z)) ^ ((y) & (z))) #define Sum0(x) (ROTR((x),2) ^ ROTR((x),13) ^ ROTR((x),22)) #define Sum1(x) (ROTR((x),6) ^ ROTR((x),11) ^ ROTR((x),25)) #define S0(x) (ROTR((x),7) ^ ROTR((x),18) ^ ((x)>>3)) #define S1(x) (ROTR((x),17) ^ ROTR((x),19) ^ ((x)>>10)) for(t=16;t<64;t++) w[t] = S1(w[t-2]) + w[t-7] + S0(w[t-15]) + w[t-16]; for(t=0;t<64;t++) { u32 t1,t2; t1=h+Sum1(e)+Ch(e,f,g)+k[t]+w[t]; t2=Sum0(a)+Maj(a,b,c); h=g; g=f; f=e; e=d+t1; d=c; c=b; b=a; a=t1+t2; /* printf("t=%d a=%08lX b=%08lX c=%08lX d=%08lX e=%08lX f=%08lX g=%08lX h=%08lX\n",t,a,b,c,d,e,f,g,h); */ } /* update chaining vars */ hd->h0 += a; hd->h1 += b; hd->h2 += c; hd->h3 += d; hd->h4 += e; hd->h5 += f; hd->h6 += g; hd->h7 += h; } /* Update the message digest with the contents * of INBUF with length INLEN. */ static void sha256_write( SHA256_CONTEXT *hd, byte *inbuf, size_t inlen) { if( hd->count == 64 ) { /* flush the buffer */ transform( hd, hd->buf ); burn_stack (328); hd->count = 0; hd->nblocks++; } if( !inbuf ) return; if( hd->count ) { for( ; inlen && hd->count < 64; inlen-- ) hd->buf[hd->count++] = *inbuf++; sha256_write( hd, NULL, 0 ); if( !inlen ) return; } while( inlen >= 64 ) { transform( hd, inbuf ); hd->count = 0; hd->nblocks++; inlen -= 64; inbuf += 64; } burn_stack (328); for( ; inlen && hd->count < 64; inlen-- ) hd->buf[hd->count++] = *inbuf++; } /* The routine final terminates the computation and * returns the digest. * The handle is prepared for a new cycle, but adding bytes to the * handle will the destroy the returned buffer. * Returns: 32 bytes representing the digest. When used for sha224, * we take the leftmost 28 of those bytes. */ static void sha256_final(SHA256_CONTEXT *hd) { u32 t, msb, lsb; byte *p; sha256_write(hd, NULL, 0); /* flush */; t = hd->nblocks; /* multiply by 64 to make a byte count */ lsb = t << 6; msb = t >> 26; /* add the count */ t = lsb; if( (lsb += hd->count) < t ) msb++; /* multiply by 8 to make a bit count */ t = lsb; lsb <<= 3; msb <<= 3; msb |= t >> 29; if( hd->count < 56 ) { /* enough room */ hd->buf[hd->count++] = 0x80; /* pad */ while( hd->count < 56 ) hd->buf[hd->count++] = 0; /* pad */ } else { /* need one extra block */ hd->buf[hd->count++] = 0x80; /* pad character */ while( hd->count < 64 ) hd->buf[hd->count++] = 0; sha256_write(hd, NULL, 0); /* flush */; memset(hd->buf, 0, 56 ); /* fill next block with zeroes */ } /* append the 64 bit count */ hd->buf[56] = msb >> 24; hd->buf[57] = msb >> 16; hd->buf[58] = msb >> 8; hd->buf[59] = msb ; hd->buf[60] = lsb >> 24; hd->buf[61] = lsb >> 16; hd->buf[62] = lsb >> 8; hd->buf[63] = lsb ; transform( hd, hd->buf ); burn_stack (328); p = hd->buf; #ifdef BIG_ENDIAN_HOST #define X(a) do { *(u32*)p = hd->h##a ; p += 4; } while(0) #else /* little endian */ #define X(a) do { *p++ = hd->h##a >> 24; *p++ = hd->h##a >> 16; \ *p++ = hd->h##a >> 8; *p++ = hd->h##a; } while(0) #endif X(0); X(1); X(2); X(3); X(4); X(5); X(6); /* Note that this last chunk is included even for SHA224. We just ignore it. */ X(7); #undef X } static byte * sha256_read( SHA256_CONTEXT *hd ) { return hd->buf; } /**************** * Return some information about the algorithm. We need algo here to * distinguish different flavors of the algorithm. * Returns: A pointer to string describing the algorithm or NULL if * the ALGO is invalid. */ const char * sha256_get_info( int algo, size_t *contextsize, byte **r_asnoid, int *r_asnlen, int *r_mdlen, void (**r_init)( void *c ), void (**r_write)( void *c, byte *buf, size_t nbytes ), void (**r_final)( void *c ), byte *(**r_read)( void *c ) ) { static byte asn[] = /* Object ID is 2.16.840.1.101.3.4.2.1 */ { 0x30, 0x31, 0x30, 0x0d, 0x06, 0x09, 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x01, 0x05, 0x00, 0x04, 0x20 }; if( algo != 8 ) return NULL; *contextsize = sizeof(SHA256_CONTEXT); *r_asnoid = asn; *r_asnlen = DIM(asn); *r_mdlen = 32; *(void (**)(SHA256_CONTEXT *))r_init = sha256_init; *(void (**)(SHA256_CONTEXT *, byte*, size_t))r_write = sha256_write; *(void (**)(SHA256_CONTEXT *))r_final = sha256_final; *(byte *(**)(SHA256_CONTEXT *))r_read = sha256_read; return "SHA256"; } /* SHA224 is really a truncated SHA256 with a different initialization */ const char * sha224_get_info( int algo, size_t *contextsize, byte **r_asnoid, int *r_asnlen, int *r_mdlen, void (**r_init)( void *c ), void (**r_write)( void *c, byte *buf, size_t nbytes ), void (**r_final)( void *c ), byte *(**r_read)( void *c ) ) { static byte asn[] = /* Object ID is 2.16.840.1.101.3.4.2.4 */ { 0x30, 0x2D, 0x30, 0x0d, 0x06, 0x09, 0x60, 0x86, 0x48, 0x01, 0x65, 0x03, 0x04, 0x02, 0x04, 0x05, 0x00, 0x04, 0x1C }; if( algo != 11 ) return NULL; *contextsize = sizeof(SHA256_CONTEXT); *r_asnoid = asn; *r_asnlen = DIM(asn); *r_mdlen = 28; *(void (**)(SHA256_CONTEXT *))r_init = sha224_init; *(void (**)(SHA256_CONTEXT *, byte*, size_t))r_write = sha256_write; *(void (**)(SHA256_CONTEXT *))r_final = sha256_final; *(byte *(**)(SHA256_CONTEXT *))r_read = sha256_read; return "SHA224"; }