/* 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 <http://www.gnu.org/licenses/>.
*/
/* 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 <config.h>
#include <string.h>
#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";
}