text: /*
   *  FIPS-180-1 compliant SHA-1 implementation
   *
   *  Based on XySSL: Copyright (C) 2006-2008  Christophe Devine
   *
   *  Copyright (C) 2009  Paul Bakker <polarssl_maintainer at polarssl dot org>
   *
   *  This program 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 2 of the License, or
   *  (at your option) any later version.
   *
   *  This program 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, write to the Free Software Foundation, Inc.,
   *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
   */
  /*
   *  The SHA-1 standard was published by NIST in 1993.
   *
   *  http://www.itl.nist.gov/fipspubs/fip180-1.htm
   */
  
  /* $Cambridge: exim/exim-src/src/pdkim/sha1.c,v 1.2 2009/06/10 07:34:05 tom Exp $ */
  
  #include "sha1.h"
  
  #include <string.h>
  #include <stdio.h>
  
  /*
   * 32-bit integer manipulation macros (big endian)
   */
  #ifndef GET_ULONG_BE
  #define GET_ULONG_BE(n,b,i)                             \
  {                                                       \
      (n) = ( (unsigned long) (b)[(i)    ] << 24 )        \
          | ( (unsigned long) (b)[(i) + 1] << 16 )        \
          | ( (unsigned long) (b)[(i) + 2] <<  8 )        \
          | ( (unsigned long) (b)[(i) + 3]       );       \
  }
  #endif
  
  #ifndef PUT_ULONG_BE
  #define PUT_ULONG_BE(n,b,i)                             \
  {                                                       \
      (b)[(i)    ] = (unsigned char) ( (n) >> 24 );       \
      (b)[(i) + 1] = (unsigned char) ( (n) >> 16 );       \
      (b)[(i) + 2] = (unsigned char) ( (n) >>  8 );       \
      (b)[(i) + 3] = (unsigned char) ( (n)       );       \
  }
  #endif
  
  /*
   * SHA-1 context setup
   */
  void sha1_starts( sha1_context *ctx )
  {
      ctx->total[0] = 0;
      ctx->total[1] = 0;
  
      ctx->state[0] = 0x67452301;
      ctx->state[1] = 0xEFCDAB89;
      ctx->state[2] = 0x98BADCFE;
      ctx->state[3] = 0x10325476;
      ctx->state[4] = 0xC3D2E1F0;
  }
  
  static void sha1_process( sha1_context *ctx, unsigned char data[64] )
  {
      unsigned long temp, W[16], A, B, C, D, E;
  
      GET_ULONG_BE( W[ 0], data,  0 );
      GET_ULONG_BE( W[ 1], data,  4 );
      GET_ULONG_BE( W[ 2], data,  8 );
      GET_ULONG_BE( W[ 3], data, 12 );
      GET_ULONG_BE( W[ 4], data, 16 );
      GET_ULONG_BE( W[ 5], data, 20 );
      GET_ULONG_BE( W[ 6], data, 24 );
      GET_ULONG_BE( W[ 7], data, 28 );
      GET_ULONG_BE( W[ 8], data, 32 );
      GET_ULONG_BE( W[ 9], data, 36 );
      GET_ULONG_BE( W[10], data, 40 );
      GET_ULONG_BE( W[11], data, 44 );
      GET_ULONG_BE( W[12], data, 48 );
      GET_ULONG_BE( W[13], data, 52 );
      GET_ULONG_BE( W[14], data, 56 );
      GET_ULONG_BE( W[15], data, 60 );
  
  #define S(x,n) ((x << n) | ((x & 0xFFFFFFFF) >> (32 - n)))
  
  #define R(t)                                            \
  (                                                       \
      temp = W[(t -  3) & 0x0F] ^ W[(t - 8) & 0x0F] ^     \
             W[(t - 14) & 0x0F] ^ W[ t      & 0x0F],      \
      ( W[t & 0x0F] = S(temp,1) )                         \
  )
  
  #define P(a,b,c,d,e,x)                                  \
  {                                                       \
      e += S(a,5) + F(b,c,d) + K + x; b = S(b,30);        \
  }
  
      A = ctx->state[0];
      B = ctx->state[1];
      C = ctx->state[2];
      D = ctx->state[3];
      E = ctx->state[4];
  
  #define F(x,y,z) (z ^ (x & (y ^ z)))
  #define K 0x5A827999
  
      P( A, B, C, D, E, W[0]  );
      P( E, A, B, C, D, W[1]  );
      P( D, E, A, B, C, W[2]  );
      P( C, D, E, A, B, W[3]  );
      P( B, C, D, E, A, W[4]  );
      P( A, B, C, D, E, W[5]  );
      P( E, A, B, C, D, W[6]  );
      P( D, E, A, B, C, W[7]  );
      P( C, D, E, A, B, W[8]  );
      P( B, C, D, E, A, W[9]  );
      P( A, B, C, D, E, W[10] );
      P( E, A, B, C, D, W[11] );
      P( D, E, A, B, C, W[12] );
      P( C, D, E, A, B, W[13] );
      P( B, C, D, E, A, W[14] );
      P( A, B, C, D, E, W[15] );
      P( E, A, B, C, D, R(16) );
      P( D, E, A, B, C, R(17) );
      P( C, D, E, A, B, R(18) );
      P( B, C, D, E, A, R(19) );
  
  #undef K
  #undef F
  
  #define F(x,y,z) (x ^ y ^ z)
  #define K 0x6ED9EBA1
  
      P( A, B, C, D, E, R(20) );
      P( E, A, B, C, D, R(21) );
      P( D, E, A, B, C, R(22) );
      P( C, D, E, A, B, R(23) );
      P( B, C, D, E, A, R(24) );
      P( A, B, C, D, E, R(25) );
      P( E, A, B, C, D, R(26) );
      P( D, E, A, B, C, R(27) );
      P( C, D, E, A, B, R(28) );
      P( B, C, D, E, A, R(29) );
      P( A, B, C, D, E, R(30) );
      P( E, A, B, C, D, R(31) );
      P( D, E, A, B, C, R(32) );
      P( C, D, E, A, B, R(33) );
      P( B, C, D, E, A, R(34) );
      P( A, B, C, D, E, R(35) );
      P( E, A, B, C, D, R(36) );
      P( D, E, A, B, C, R(37) );
      P( C, D, E, A, B, R(38) );
      P( B, C, D, E, A, R(39) );
  
  #undef K
  #undef F
  
  #define F(x,y,z) ((x & y) | (z & (x | y)))
  #define K 0x8F1BBCDC
  
      P( A, B, C, D, E, R(40) );
      P( E, A, B, C, D, R(41) );
      P( D, E, A, B, C, R(42) );
      P( C, D, E, A, B, R(43) );
      P( B, C, D, E, A, R(44) );
      P( A, B, C, D, E, R(45) );
      P( E, A, B, C, D, R(46) );
      P( D, E, A, B, C, R(47) );
      P( C, D, E, A, B, R(48) );
      P( B, C, D, E, A, R(49) );
      P( A, B, C, D, E, R(50) );
      P( E, A, B, C, D, R(51) );
      P( D, E, A, B, C, R(52) );
      P( C, D, E, A, B, R(53) );
      P( B, C, D, E, A, R(54) );
      P( A, B, C, D, E, R(55) );
      P( E, A, B, C, D, R(56) );
      P( D, E, A, B, C, R(57) );
      P( C, D, E, A, B, R(58) );
      P( B, C, D, E, A, R(59) );
  
  #undef K
  #undef F
  
  #define F(x,y,z) (x ^ y ^ z)
  #define K 0xCA62C1D6
  
      P( A, B, C, D, E, R(60) );
      P( E, A, B, C, D, R(61) );
      P( D, E, A, B, C, R(62) );
      P( C, D, E, A, B, R(63) );
      P( B, C, D, E, A, R(64) );
      P( A, B, C, D, E, R(65) );
      P( E, A, B, C, D, R(66) );
      P( D, E, A, B, C, R(67) );
      P( C, D, E, A, B, R(68) );
      P( B, C, D, E, A, R(69) );
      P( A, B, C, D, E, R(70) );
      P( E, A, B, C, D, R(71) );
      P( D, E, A, B, C, R(72) );
      P( C, D, E, A, B, R(73) );
      P( B, C, D, E, A, R(74) );
      P( A, B, C, D, E, R(75) );
      P( E, A, B, C, D, R(76) );
      P( D, E, A, B, C, R(77) );
      P( C, D, E, A, B, R(78) );
      P( B, C, D, E, A, R(79) );
  
  #undef K
  #undef F
  
      ctx->state[0] += A;
      ctx->state[1] += B;
      ctx->state[2] += C;
      ctx->state[3] += D;
      ctx->state[4] += E;
  }
  
  /*
   * SHA-1 process buffer
   */
  void sha1_update( sha1_context *ctx, unsigned char *input, int ilen )
  {
      int fill;
      unsigned long left;
  
      if( ilen <= 0 )
          return;
  
      left = ctx->total[0] & 0x3F;
      fill = 64 - left;
  
      ctx->total[0] += ilen;
      ctx->total[0] &= 0xFFFFFFFF;
  
      if( ctx->total[0] < (unsigned long) ilen )
          ctx->total[1]++;
  
      if( left && ilen >= fill )
      {
          memcpy( (void *) (ctx->buffer + left),
                  (void *) input, fill );
          sha1_process( ctx, ctx->buffer );
          input += fill;
          ilen  -= fill;
          left = 0;
      }
  
      while( ilen >= 64 )
      {
          sha1_process( ctx, input );
          input += 64;
          ilen  -= 64;
      }
  
      if( ilen > 0 )
      {
          memcpy( (void *) (ctx->buffer + left),
                  (void *) input, ilen );
      }
  }
  
  static const unsigned char sha1_padding[64] =
  {
   0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
      0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
      0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
      0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
  };
  
  /*
   * SHA-1 final digest
   */
  void sha1_finish( sha1_context *ctx, unsigned char output[20] )
  {
      unsigned long last, padn;
      unsigned long high, low;
      unsigned char msglen[8];
  
      high = ( ctx->total[0] >> 29 )
           | ( ctx->total[1] <<  3 );
      low  = ( ctx->total[0] <<  3 );
  
      PUT_ULONG_BE( high, msglen, 0 );
      PUT_ULONG_BE( low,  msglen, 4 );
  
      last = ctx->total[0] & 0x3F;
      padn = ( last < 56 ) ? ( 56 - last ) : ( 120 - last );
  
      sha1_update( ctx, (unsigned char *) sha1_padding, padn );
      sha1_update( ctx, msglen, 8 );
  
      PUT_ULONG_BE( ctx->state[0], output,  0 );
      PUT_ULONG_BE( ctx->state[1], output,  4 );
      PUT_ULONG_BE( ctx->state[2], output,  8 );
      PUT_ULONG_BE( ctx->state[3], output, 12 );
      PUT_ULONG_BE( ctx->state[4], output, 16 );
  }
  
  /*
   * output = SHA-1( input buffer )
   */
  void sha1_oneshot( unsigned char *input, int ilen, unsigned char output[20] )
  {
      sha1_context ctx;
  
      sha1_starts( &ctx );
      sha1_update( &ctx, input, ilen );
      sha1_finish( &ctx, output );
  
      memset( &ctx, 0, sizeof( sha1_context ) );
  }
  
  /*
   * output = SHA-1( file contents )
   */
  int sha1_file( char *path, unsigned char output[20] )
  {
      FILE *f;
      size_t n;
      sha1_context ctx;
      unsigned char buf[1024];
  
      if( ( f = fopen( path, "rb" ) ) == NULL )
          return( 1 );
  
      sha1_starts( &ctx );
  
      while( ( n = fread( buf, 1, sizeof( buf ), f ) ) > 0 )
          sha1_update( &ctx, buf, (int) n );
  
      sha1_finish( &ctx, output );
  
      memset( &ctx, 0, sizeof( sha1_context ) );
  
      if( ferror( f ) != 0 )
      {
          fclose( f );
          return( 2 );
      }
  
      fclose( f );
      return( 0 );
  }
  
  /*
   * SHA-1 HMAC context setup
   */
  void sha1_hmac_starts( sha1_context *ctx, unsigned char *key, int keylen )
  {
      int i;
      unsigned char sum[20];
  
      if( keylen > 64 )
      {
          sha1_oneshot( key, keylen, sum );
          keylen = 20;
          key = sum;
      }
  
      memset( ctx->ipad, 0x36, 64 );
      memset( ctx->opad, 0x5C, 64 );
  
      for( i = 0; i < keylen; i++ )
      {
          ctx->ipad[i] = (unsigned char)( ctx->ipad[i] ^ key[i] );
          ctx->opad[i] = (unsigned char)( ctx->opad[i] ^ key[i] );
      }
  
      sha1_starts( ctx );
      sha1_update( ctx, ctx->ipad, 64 );
  
      memset( sum, 0, sizeof( sum ) );
  }
  
  /*
   * SHA-1 HMAC process buffer
   */
  void sha1_hmac_update( sha1_context *ctx, unsigned char *input, int ilen )
  {
      sha1_update( ctx, input, ilen );
  }
  
  /*
   * SHA-1 HMAC final digest
   */
  void sha1_hmac_finish( sha1_context *ctx, unsigned char output[20] )
  {
      unsigned char tmpbuf[20];
  
      sha1_finish( ctx, tmpbuf );
      sha1_starts( ctx );
      sha1_update( ctx, ctx->opad, 64 );
      sha1_update( ctx, tmpbuf, 20 );
      sha1_finish( ctx, output );
  
      memset( tmpbuf, 0, sizeof( tmpbuf ) );
  }
  
  /*
   * output = HMAC-SHA-1( hmac key, input buffer )
   */
  void sha1_hmac( unsigned char *key, int keylen,
                  unsigned char *input, int ilen,
                  unsigned char output[20] )
  {
      sha1_context ctx;
  
      sha1_hmac_starts( &ctx, key, keylen );
      sha1_hmac_update( &ctx, input, ilen );
      sha1_hmac_finish( &ctx, output );
  
      memset( &ctx, 0, sizeof( sha1_context ) );
  }
  