sha1.c 10.7 KB
Newer Older
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
/* Copyright (C) 2000 MySQL AB & MySQL Finland AB & TCX DataKonsult AB

 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */
 
17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49
/*
 sha1.c
 Original Source from: http://www.faqs.org/rfcs/rfc3174.html
 
 Description:
       This file implements the Secure Hashing Algorithm 1 as
       defined in FIPS PUB 180-1 published April 17, 1995.
 
       The SHA-1, produces a 160-bit message digest for a given
       data stream.  It should take about 2**n steps to find a
       message with the same digest as a given message and
       2**(n/2) to find any two messages with the same digest,
       when n is the digest size in bits.  Therefore, this
       algorithm can serve as a means of providing a
       "fingerprint" for a message.
 
   Portability Issues:
       SHA-1 is defined in terms of 32-bit "words".  This code
       uses <stdint.h> (included via "sha1.h" to define 32 and 8
       bit unsigned integer types.  If your C compiler does not
       support 32 bit unsigned integers, this code is not
       appropriate.
 
   Caveats:
       SHA-1 is designed to work with messages less than 2^64 bits
       long.  Although SHA-1 allows a message digest to be generated
       for messages of any number of bits less than 2^64, this
       implementation only works with messages with a length that is
       a multiple of the size of an 8-bit character.
 
*/
 
/* 
50
  Modified 2002 by Peter Zaitsev to 
51 52 53 54 55 56
  - fit to new prototypes according to MySQL standard
  - Some optimizations 
  - All checking is now done in debug only mode
  - More comments 
*/

57 58
#include "my_global.h"
#include "m_string.h"
59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164
#include "sha1.h"

/*
 Define the SHA1 circular left shift macro
*/
 
#define SHA1CircularShift(bits,word) \
                (((word) << (bits)) | ((word) >> (32-(bits))))

/* Local Function Prototyptes */
void SHA1PadMessage(SHA1_CONTEXT*);
void SHA1ProcessMessageBlock(SHA1_CONTEXT*);

/*
 sha1_reset
 
 Description:
       This function will initialize the SHA1Context in preparation
       for computing a new SHA1 message digest.
 
 Parameters:
       context: [in/out]
           The context to reset.
 
 Returns:
       sha Error Code.
 
*/
 

const uint32 sha_const_key[5]=
{
  0x67452301,
  0xEFCDAB89,
  0x98BADCFE,
  0x10325476,
  0xC3D2E1F0
};


int sha1_reset(SHA1_CONTEXT *context)
{

#ifndef DBUG_OFF 
  if (!context)
  {
    return SHA_NULL;
  }
#endif    

  context->Length                 = 0;
  context->Message_Block_Index    = 0;
  
  context->Intermediate_Hash[0]   = sha_const_key[0];
  context->Intermediate_Hash[1]   = sha_const_key[1];
  context->Intermediate_Hash[2]   = sha_const_key[2];
  context->Intermediate_Hash[3]   = sha_const_key[3];
  context->Intermediate_Hash[4]   = sha_const_key[4];

  context->Computed   = 0;
  context->Corrupted  = 0;

  return SHA_SUCCESS;
}

/*
 sha1_result
 
 Description:
       This function will return the 160-bit message digest into the
       Message_Digest array  provided by the caller.
       NOTE: The first octet of hash is stored in the 0th element,
             the last octet of hash in the 19th element.
 
 Parameters:
       context: [in/out]
           The context to use to calculate the SHA-1 hash.
       Message_Digest: [out]
           Where the digest is returned.
 
 Returns:
       sha Error Code.
 
*/

int sha1_result( SHA1_CONTEXT *context,
                uint8 Message_Digest[SHA1_HASH_SIZE])
{
  int i;
    
#ifndef DBUG_OFF 
  if (!context || !Message_Digest)
  {
    return SHA_NULL;
  }

  if (context->Corrupted)
  {
    return context->Corrupted;
  }

  if (!context->Computed)
  {

#endif     
    SHA1PadMessage(context);
165 166
     /* message may be sensitive, clear it out */
    bzero((char*) context->Message_Block,64);
167 168 169 170 171 172 173 174 175
    context->Length   = 0;    /* and clear length  */
    context->Computed = 1;

#ifndef DBUG_OFF
  }
#endif

  for (i = 0; i < SHA1_HASH_SIZE; i++)
  {
176 177
    Message_Digest[i] = (context->Intermediate_Hash[i>>2] >> 8 
                         * ( 3 - ( i & 0x03 ) ));
178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228
  }
  
  return SHA_SUCCESS;
}

/*
 sha1_input
 
 Description:
       This function accepts an array of octets as the next portion
       of the message.
 
   Parameters:
       context: [in/out]
           The SHA context to update
       message_array: [in]
           An array of characters representing the next portion of
           the message.
       length: [in]
           The length of the message in message_array
 
   Returns:
       sha Error Code.
 
*/

int sha1_input(SHA1_CONTEXT *context, const uint8 *message_array,
               unsigned length)
{
  if (!length)
  {
    return SHA_SUCCESS;
  }
#ifndef DBUG_OFF 
  /* We assume client konows what it is doing in non-debug mode */
  if (!context || !message_array)
  {
    return SHA_NULL;
  }
  if (context->Computed)
  {
    context->Corrupted = SHA_STATE_ERROR;
    return SHA_STATE_ERROR;
  }

  if (context->Corrupted)
  {
    return context->Corrupted;
  }    
#endif     

229
  while (length--)
230 231 232 233 234 235 236 237 238 239 240 241 242 243
  {
    context->Message_Block[context->Message_Block_Index++] =
                    (*message_array & 0xFF);
    context->Length  += 8;  /* Length is in bits */ 

#ifndef DBUG_OFF    
    /* 
     Then we're not debugging we assume we never will get message longer
     2^64 bits.
    */
    if (context->Length == 0)
    {
      /* Message is too long */
      context->Corrupted = 1;
244
      return 1;
245 246 247 248 249 250 251
    }
#endif 
	
    if (context->Message_Block_Index == 64)
    {
      SHA1ProcessMessageBlock(context);
    }
252
    message_array++;  
253
  }
254
  
255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279
  return SHA_SUCCESS;
}

/*
   SHA1ProcessMessageBlock
 
   Description:
       This function will process the next 512 bits of the message
       stored in the Message_Block array.
 
   Parameters:
       None.
 
   Returns:
       Nothing.
 
   Comments:

       Many of the variable names in this code, especially the
       single character names, were used because those were the
       names used in the publication.
 
 
*/

280
/* Constants defined in SHA-1   */
281
static const uint32  K[]=   
282
{ 
283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311
  0x5A827999,
  0x6ED9EBA1,
  0x8F1BBCDC,
  0xCA62C1D6
};


void SHA1ProcessMessageBlock(SHA1_CONTEXT *context)
{
  int           t;                 /* Loop counter                */
  uint32        temp;              /* Temporary word value        */
  uint32        W[80];             /* Word sequence               */
  uint32        A, B, C, D, E;     /* Word buffers                */
  int index;
    
  /*
   Initialize the first 16 words in the array W
   */

  for (t = 0; t < 16; t++)
  {
    index=t*4;
    W[t] = context->Message_Block[index] << 24;
    W[t] |= context->Message_Block[index + 1] << 16;
    W[t] |= context->Message_Block[index + 2] << 8;
    W[t] |= context->Message_Block[index + 3];
  }


312
  for (t = 16; t < 80; t++)
313 314 315 316 317 318 319 320 321 322
  {
    W[t] = SHA1CircularShift(1,W[t-3] ^ W[t-8] ^ W[t-14] ^ W[t-16]);
  }

  A = context->Intermediate_Hash[0];
  B = context->Intermediate_Hash[1];
  C = context->Intermediate_Hash[2];
  D = context->Intermediate_Hash[3];
  E = context->Intermediate_Hash[4];

323
  for (t = 0; t < 20; t++)
324 325 326 327 328 329 330 331 332 333
  {
    temp =  SHA1CircularShift(5,A) +
            ((B & C) | ((~B) & D)) + E + W[t] + K[0];
    E = D;
    D = C;
    C = SHA1CircularShift(30,B);
    B = A;
    A = temp;
  }
  
334
  for (t = 20; t < 40; t++)
335 336 337 338 339 340 341 342 343
  {
    temp = SHA1CircularShift(5,A) + (B ^ C ^ D) + E + W[t] + K[1];
    E = D;
    D = C;
    C = SHA1CircularShift(30,B);
    B = A;
    A = temp;
  }

344
  for (t = 40; t < 60; t++)
345 346 347 348 349 350 351 352 353 354
  {
    temp = SHA1CircularShift(5,A) +
           ((B & C) | (B & D) | (C & D)) + E + W[t] + K[2];
    E = D;
    D = C;
    C = SHA1CircularShift(30,B);
    B = A;
    A = temp;
  }

355
  for (t = 60; t < 80; t++)
356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417
  {
    temp = SHA1CircularShift(5,A) + (B ^ C ^ D) + E + W[t] + K[3];
    E = D;
    D = C;
    C = SHA1CircularShift(30,B);
    B = A;
    A = temp;
  }

  context->Intermediate_Hash[0] += A;
  context->Intermediate_Hash[1] += B;
  context->Intermediate_Hash[2] += C;
  context->Intermediate_Hash[3] += D;
  context->Intermediate_Hash[4] += E;
  
  context->Message_Block_Index = 0;
}


/*
   SHA1PadMessage
 

   Description:
       According to the standard, the message must be padded to an even
       512 bits.  The first padding bit must be a '1'.  The last 64
       bits represent the length of the original message.  All bits in
       between should be 0.  This function will pad the message
       according to those rules by filling the Message_Block array
       accordingly.  It will also call the ProcessMessageBlock function
       provided appropriately.  When it returns, it can be assumed that
       the message digest has been computed.
 
   Parameters:
       context: [in/out]
           The context to pad
       ProcessMessageBlock: [in]
           The appropriate SHA*ProcessMessageBlock function
   Returns:
       Nothing.
 
*/

void SHA1PadMessage(SHA1_CONTEXT *context)
{
  /*
   Check to see if the current message block is too small to hold
   the initial padding bits and length.  If so, we will pad the
   block, process it, and then continue padding into a second
   block.
  */
  
  int i=context->Message_Block_Index;

  if (i > 55)
  {
    context->Message_Block[i++] = 0x80;
    bzero((char*) &context->Message_Block[i],
          sizeof(context->Message_Block[0])*(64-i));
    context->Message_Block_Index=64;
    
    /* This function sets context->Message_Block_Index to zero  */
418 419
    SHA1ProcessMessageBlock(context);    

420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448
    bzero((char*) &context->Message_Block[0],
          sizeof(context->Message_Block[0])*56);
    context->Message_Block_Index=56;
    
  }  
  else
  {
    context->Message_Block[i++] = 0x80;
    bzero((char*) &context->Message_Block[i],
          sizeof(context->Message_Block[0])*(56-i));
    context->Message_Block_Index=56;
  }
            
  /*
   Store the message length as the last 8 octets
  */
  
  context->Message_Block[56] = context->Length >> 56;
  context->Message_Block[57] = context->Length >> 48;
  context->Message_Block[58] = context->Length >> 40;
  context->Message_Block[59] = context->Length >> 32;
  context->Message_Block[60] = context->Length >> 24;
  context->Message_Block[61] = context->Length >> 16;
  context->Message_Block[62] = context->Length >> 8;
  context->Message_Block[63] = context->Length;

  SHA1ProcessMessageBlock(context);
}