crypto/cipher/sha1.c

   1 /* sha1.c - SHA1 hash function
   2  *      Copyright (C) 1998, 2001, 2002, 2003 Free Software Foundation, Inc.
   3  *
   4  * This file is part of Libgcrypt.
   5  *
   6  * Libgcrypt is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU Lesser General Public License as
   8  * published by the Free Software Foundation; either version 2.1 of
   9  * the License, or (at your option) any later version.
  10  *
  11  * Libgcrypt is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
  19  */
  20
  21
  22 /*  Test vectors:
  23  *
  24  *  "abc"
  25  *  A999 3E36 4706 816A BA3E  2571 7850 C26C 9CD0 D89D
  26  *
  27  *  "abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq"
  28  *  8498 3E44 1C3B D26E BAAE  4AA1 F951 29E5 E546 70F1
  29  */
  30
  31
  32 #include <config.h>
  33 #include <stdio.h>
  34 #include <stdlib.h>
  35 #include <string.h>
  36 #include <assert.h>
  37 #include "g10lib.h"
  38 #include "memory.h"
  39 #include "dynload.h"
  40 #include "bithelp.h"
  41
  42
  43 typedef struct {
  44     u32  h0,h1,h2,h3,h4;
  45     u32  nblocks;
  46     byte buf[64];
  47     int  count;
  48 } SHA1_CONTEXT;
  49
  50
  51 static void
  52 sha1_init( SHA1_CONTEXT *hd )
  53 {
  54     hd->h0 = 0x67452301;
  55     hd->h1 = 0xefcdab89;
  56     hd->h2 = 0x98badcfe;
  57     hd->h3 = 0x10325476;
  58     hd->h4 = 0xc3d2e1f0;
  59     hd->nblocks = 0;
  60     hd->count = 0;
  61 }
  62
  63
  64 /****************
  65  * Transform the message X which consists of 16 32-bit-words
  66  */
  67 static void
  68 transform( SHA1_CONTEXT *hd, byte *data )
  69 {
  70     register u32 a,b,c,d,e,tm;
  71     u32 x[16];
  72
  73     /* get values from the chaining vars */
  74     a = hd->h0;
  75     b = hd->h1;
  76     c = hd->h2;
  77     d = hd->h3;
  78     e = hd->h4;
  79
  80   #ifdef BIG_ENDIAN_HOST
  81     memcpy( x, data, 64 );
  82   #else
  83     { int i;
  84       byte *p2;
  85       for(i=0, p2=(byte*)x; i < 16; i++, p2 += 4 ) {
  86         p2[3] = *data++;
  87         p2[2] = *data++;
  88         p2[1] = *data++;
  89         p2[0] = *data++;
  90       }
  91     }
  92   #endif
  93
  94
  95 #define K1  0x5A827999L
  96 #define K2  0x6ED9EBA1L
  97 #define K3  0x8F1BBCDCL
  98 #define K4  0xCA62C1D6L
  99 #define F1(x,y,z)   ( z ^ ( x & ( y ^ z ) ) )
 100 #define F2(x,y,z)   ( x ^ y ^ z )
 101 #define F3(x,y,z)   ( ( x & y ) | ( z & ( x | y ) ) )
 102 #define F4(x,y,z)   ( x ^ y ^ z )
 103
 104
 105 #define M(i) ( tm =   x[i&0x0f] ^ x[(i-14)&0x0f] \
 106                     ^ x[(i-8)&0x0f] ^ x[(i-3)&0x0f] \
 107                , (x[i&0x0f] = rol(tm, 1)) )
 108
 109 #define R(a,b,c,d,e,f,k,m)  do { e += rol( a, 5 )     \
 110                                       + f( b, c, d )  \
 111                                       + k             \
 112                                       + m;            \
 113                                  b = rol( b, 30 );    \
 114                                } while(0)
 115     R( a, b, c, d, e, F1, K1, x[ 0] );
 116     R( e, a, b, c, d, F1, K1, x[ 1] );
 117     R( d, e, a, b, c, F1, K1, x[ 2] );
 118     R( c, d, e, a, b, F1, K1, x[ 3] );
 119     R( b, c, d, e, a, F1, K1, x[ 4] );
 120     R( a, b, c, d, e, F1, K1, x[ 5] );
 121     R( e, a, b, c, d, F1, K1, x[ 6] );
 122     R( d, e, a, b, c, F1, K1, x[ 7] );
 123     R( c, d, e, a, b, F1, K1, x[ 8] );
 124     R( b, c, d, e, a, F1, K1, x[ 9] );
 125     R( a, b, c, d, e, F1, K1, x[10] );
 126     R( e, a, b, c, d, F1, K1, x[11] );
 127     R( d, e, a, b, c, F1, K1, x[12] );
 128     R( c, d, e, a, b, F1, K1, x[13] );
 129     R( b, c, d, e, a, F1, K1, x[14] );
 130     R( a, b, c, d, e, F1, K1, x[15] );
 131     R( e, a, b, c, d, F1, K1, M(16) );
 132     R( d, e, a, b, c, F1, K1, M(17) );
 133     R( c, d, e, a, b, F1, K1, M(18) );
 134     R( b, c, d, e, a, F1, K1, M(19) );
 135     R( a, b, c, d, e, F2, K2, M(20) );
 136     R( e, a, b, c, d, F2, K2, M(21) );
 137     R( d, e, a, b, c, F2, K2, M(22) );
 138     R( c, d, e, a, b, F2, K2, M(23) );
 139     R( b, c, d, e, a, F2, K2, M(24) );
 140     R( a, b, c, d, e, F2, K2, M(25) );
 141     R( e, a, b, c, d, F2, K2, M(26) );
 142     R( d, e, a, b, c, F2, K2, M(27) );
 143     R( c, d, e, a, b, F2, K2, M(28) );
 144     R( b, c, d, e, a, F2, K2, M(29) );
 145     R( a, b, c, d, e, F2, K2, M(30) );
 146     R( e, a, b, c, d, F2, K2, M(31) );
 147     R( d, e, a, b, c, F2, K2, M(32) );
 148     R( c, d, e, a, b, F2, K2, M(33) );
 149     R( b, c, d, e, a, F2, K2, M(34) );
 150     R( a, b, c, d, e, F2, K2, M(35) );
 151     R( e, a, b, c, d, F2, K2, M(36) );
 152     R( d, e, a, b, c, F2, K2, M(37) );
 153     R( c, d, e, a, b, F2, K2, M(38) );
 154     R( b, c, d, e, a, F2, K2, M(39) );
 155     R( a, b, c, d, e, F3, K3, M(40) );
 156     R( e, a, b, c, d, F3, K3, M(41) );
 157     R( d, e, a, b, c, F3, K3, M(42) );
 158     R( c, d, e, a, b, F3, K3, M(43) );
 159     R( b, c, d, e, a, F3, K3, M(44) );
 160     R( a, b, c, d, e, F3, K3, M(45) );
 161     R( e, a, b, c, d, F3, K3, M(46) );
 162     R( d, e, a, b, c, F3, K3, M(47) );
 163     R( c, d, e, a, b, F3, K3, M(48) );
 164     R( b, c, d, e, a, F3, K3, M(49) );
 165     R( a, b, c, d, e, F3, K3, M(50) );
 166     R( e, a, b, c, d, F3, K3, M(51) );
 167     R( d, e, a, b, c, F3, K3, M(52) );
 168     R( c, d, e, a, b, F3, K3, M(53) );
 169     R( b, c, d, e, a, F3, K3, M(54) );
 170     R( a, b, c, d, e, F3, K3, M(55) );
 171     R( e, a, b, c, d, F3, K3, M(56) );
 172     R( d, e, a, b, c, F3, K3, M(57) );
 173     R( c, d, e, a, b, F3, K3, M(58) );
 174     R( b, c, d, e, a, F3, K3, M(59) );
 175     R( a, b, c, d, e, F4, K4, M(60) );
 176     R( e, a, b, c, d, F4, K4, M(61) );
 177     R( d, e, a, b, c, F4, K4, M(62) );
 178     R( c, d, e, a, b, F4, K4, M(63) );
 179     R( b, c, d, e, a, F4, K4, M(64) );
 180     R( a, b, c, d, e, F4, K4, M(65) );
 181     R( e, a, b, c, d, F4, K4, M(66) );
 182     R( d, e, a, b, c, F4, K4, M(67) );
 183     R( c, d, e, a, b, F4, K4, M(68) );
 184     R( b, c, d, e, a, F4, K4, M(69) );
 185     R( a, b, c, d, e, F4, K4, M(70) );
 186     R( e, a, b, c, d, F4, K4, M(71) );
 187     R( d, e, a, b, c, F4, K4, M(72) );
 188     R( c, d, e, a, b, F4, K4, M(73) );
 189     R( b, c, d, e, a, F4, K4, M(74) );
 190     R( a, b, c, d, e, F4, K4, M(75) );
 191     R( e, a, b, c, d, F4, K4, M(76) );
 192     R( d, e, a, b, c, F4, K4, M(77) );
 193     R( c, d, e, a, b, F4, K4, M(78) );
 194     R( b, c, d, e, a, F4, K4, M(79) );
 195
 196     /* update chainig vars */
 197     hd->h0 += a;
 198     hd->h1 += b;
 199     hd->h2 += c;
 200     hd->h3 += d;
 201     hd->h4 += e;
 202 }
 203
 204
 205 /* Update the message digest with the contents
 206  * of INBUF with length INLEN.
 207  */
 208 static void
 209 sha1_write( SHA1_CONTEXT *hd, byte *inbuf, size_t inlen)
 210 {
 211     if( hd->count == 64 ) { /* flush the buffer */
 212         transform( hd, hd->buf );
 213         _gcry_burn_stack (88+4*sizeof(void*));
 214         hd->count = 0;
 215         hd->nblocks++;
 216     }
 217     if( !inbuf )
 218         return;
 219     if( hd->count ) {
 220         for( ; inlen && hd->count < 64; inlen-- )
 221             hd->buf[hd->count++] = *inbuf++;
 222         sha1_write( hd, NULL, 0 );
 223         if( !inlen )
 224             return;
 225     }
 226
 227     while( inlen >= 64 ) {
 228         transform( hd, inbuf );
 229         hd->count = 0;
 230         hd->nblocks++;
 231         inlen -= 64;
 232         inbuf += 64;
 233     }
 234     _gcry_burn_stack (88+4*sizeof(void*));
 235     for( ; inlen && hd->count < 64; inlen-- )
 236         hd->buf[hd->count++] = *inbuf++;
 237 }
 238
 239
 240 /* The routine final terminates the computation and
 241  * returns the digest.
 242  * The handle is prepared for a new cycle, but adding bytes to the
 243  * handle will the destroy the returned buffer.
 244  * Returns: 20 bytes representing the digest.
 245  */
 246
 247 static void
 248 sha1_final(SHA1_CONTEXT *hd)
 249 {
 250     u32 t, msb, lsb;
 251     byte *p;
 252
 253     sha1_write(hd, NULL, 0); /* flush */;
 254
 255     t = hd->nblocks;
 256     /* multiply by 64 to make a byte count */
 257     lsb = t << 6;
 258     msb = t >> 26;
 259     /* add the count */
 260     t = lsb;
 261     if( (lsb += hd->count) < t )
 262         msb++;
 263     /* multiply by 8 to make a bit count */
 264     t = lsb;
 265     lsb <<= 3;
 266     msb <<= 3;
 267     msb |= t >> 29;
 268
 269     if( hd->count < 56 ) { /* enough room */
 270         hd->buf[hd->count++] = 0x80; /* pad */
 271         while( hd->count < 56 )
 272             hd->buf[hd->count++] = 0;  /* pad */
 273     }
 274     else { /* need one extra block */
 275         hd->buf[hd->count++] = 0x80; /* pad character */
 276         while( hd->count < 64 )
 277             hd->buf[hd->count++] = 0;
 278         sha1_write(hd, NULL, 0);  /* flush */;
 279         memset(hd->buf, 0, 56 ); /* fill next block with zeroes */
 280     }
 281     /* append the 64 bit count */
 282     hd->buf[56] = msb >> 24;
 283     hd->buf[57] = msb >> 16;
 284     hd->buf[58] = msb >>  8;
 285     hd->buf[59] = msb      ;
 286     hd->buf[60] = lsb >> 24;
 287     hd->buf[61] = lsb >> 16;
 288     hd->buf[62] = lsb >>  8;
 289     hd->buf[63] = lsb      ;
 290     transform( hd, hd->buf );
 291     _gcry_burn_stack (88+4*sizeof(void*));
 292
 293     p = hd->buf;
 294   #ifdef BIG_ENDIAN_HOST
 295     #define X(a) do { *(u32*)p = hd->h##a ; p += 4; } while(0)
 296   #else /* little endian */
 297     #define X(a) do { *p++ = hd->h##a >> 24; *p++ = hd->h##a >> 16;      \
 298                       *p++ = hd->h##a >> 8; *p++ = hd->h##a; } while(0)
 299   #endif
 300     X(0);
 301     X(1);
 302     X(2);
 303     X(3);
 304     X(4);
 305   #undef X
 306
 307 }
 308
 309 static byte *
 310 sha1_read( SHA1_CONTEXT *hd )
 311 {
 312     return hd->buf;
 313 }
 314
 315 /****************
 316  * Return some information about the algorithm.  We need algo here to
 317  * distinguish different flavors of the algorithm.
 318  * Returns: A pointer to string describing the algorithm or NULL if
 319  *          the ALGO is invalid.
 320  */
 321 static const char *
 322 sha1_get_info( int algo, size_t *contextsize,
 323                byte **r_asnoid, int *r_asnlen, int *r_mdlen,
 324                void (**r_init)( void *c ),
 325                void (**r_write)( void *c, byte *buf, size_t nbytes ),
 326                void (**r_final)( void *c ),
 327                byte *(**r_read)( void *c )
 328              )
 329 {
 330     static byte asn[15] = /* Object ID is 1.3.14.3.2.26 */
 331                     { 0x30, 0x21, 0x30, 0x09, 0x06, 0x05, 0x2b, 0x0e, 0x03,
 332                       0x02, 0x1a, 0x05, 0x00, 0x04, 0x14 };
 333     if( algo != 2 )
 334         return NULL;
 335
 336     *contextsize = sizeof(SHA1_CONTEXT);
 337     *r_asnoid = asn;
 338     *r_asnlen = DIM(asn);
 339     *r_mdlen = 20;
 340     *(void  (**)(SHA1_CONTEXT *))r_init                 = sha1_init;
 341     *(void  (**)(SHA1_CONTEXT *, byte*, size_t))r_write = sha1_write;
 342     *(void  (**)(SHA1_CONTEXT *))r_final                = sha1_final;
 343     *(byte *(**)(SHA1_CONTEXT *))r_read                 = sha1_read;
 344
 345     return "SHA1";
 346 }
 347
 348
 349
 350 #ifndef IS_MODULE
 351 static
 352 #endif
 353 const char * const gnupgext_version = "SHA1 ($Revision$)";
 354
 355 static struct {
 356     int class;
 357     int version;
 358     int  value;
 359     void (*func)(void);
 360 } func_table[] = {
 361     { 10, 1, 0, (void(*)(void))sha1_get_info },
 362     { 11, 1, 2 },
 363 };
 364
 365
 366 #ifndef IS_MODULE
 367 static
 368 #endif
 369 void *
 370 gnupgext_enum_func( int what, int *sequence, int *class, int *vers )
 371 {
 372     void *ret;
 373     int i = *sequence;
 374
 375     do {
 376         if( i >= DIM(func_table) || i < 0 ) {
 377             return NULL;
 378         }
 379         *class = func_table[i].class;
 380         *vers  = func_table[i].version;
 381         switch( *class ) {
 382           case 11:
 383           case 21:
 384           case 31:
 385             ret = &func_table[i].value;
 386             break;
 387           default:
 388             ret = func_table[i].func;
 389             break;
 390         }
 391         i++;
 392     } while( what && what != *class );
 393
 394     *sequence = i;
 395     return ret;
 396 }
 397
 398
 399
 400
 401 #ifndef IS_MODULE
 402 void
 403 _gcry_sha1_constructor(void)
 404 {
 405     _gcry_register_internal_cipher_extension( gnupgext_version, gnupgext_enum_func );
 406 }
 407 #endif
 408