Return to md2c.c CVS log

Up to [PGP] / pgp / rsaref / source

Annotation of pgp/rsaref/source/md2c.c, revision 1.1

1.1     ! root        1: /* MD2C.C - RSA Data Security, Inc., MD2 message-digest algorithm
        !             2:  */
        !             3: 
        !             4: /* Copyright (C) 1990-2, RSA Data Security, Inc. Created 1990. All
        !             5:    rights reserved.
        !             6: 
        !             7:    License to copy and use this software is granted for
        !             8:    non-commercial Internet Privacy-Enhanced Mail provided that it is
        !             9:    identified as the "RSA Data Security, Inc. MD2 Message Digest
        !            10:    Algorithm" in all material mentioning or referencing this software
        !            11:    or this function.
        !            12: 
        !            13:    RSA Data Security, Inc. makes no representations concerning either
        !            14:    the merchantability of this software or the suitability of this
        !            15:    software for any particular purpose. It is provided "as is"
        !            16:    without express or implied warranty of any kind.
        !            17: 
        !            18:    These notices must be retained in any copies of any part of this
        !            19:    documentation and/or software.  
        !            20:  */
        !            21: 
        !            22: #include "global.h"
        !            23: #include "md2.h"
        !            24: 
        !            25: static void MD2Transform PROTO_LIST
        !            26:   ((unsigned char [16], unsigned char [16], unsigned char [16]));
        !            27: static void MD2_memcpy PROTO_LIST ((POINTER, POINTER, unsigned int));
        !            28: static void MD2_memset PROTO_LIST ((POINTER, int, unsigned int));
        !            29: 
        !            30: /* Permutation of 0..255 constructed from the digits of pi. It gives a
        !            31:    "random" nonlinear byte substitution operation.
        !            32:  */
        !            33: static unsigned char PI_SUBST[256] = {
        !            34:   41, 46, 67, 201, 162, 216, 124, 1, 61, 54, 84, 161, 236, 240, 6,
        !            35:   19, 98, 167, 5, 243, 192, 199, 115, 140, 152, 147, 43, 217, 188,
        !            36:   76, 130, 202, 30, 155, 87, 60, 253, 212, 224, 22, 103, 66, 111, 24,
        !            37:   138, 23, 229, 18, 190, 78, 196, 214, 218, 158, 222, 73, 160, 251,
        !            38:   245, 142, 187, 47, 238, 122, 169, 104, 121, 145, 21, 178, 7, 63,
        !            39:   148, 194, 16, 137, 11, 34, 95, 33, 128, 127, 93, 154, 90, 144, 50,
        !            40:   39, 53, 62, 204, 231, 191, 247, 151, 3, 255, 25, 48, 179, 72, 165,
        !            41:   181, 209, 215, 94, 146, 42, 172, 86, 170, 198, 79, 184, 56, 210,
        !            42:   150, 164, 125, 182, 118, 252, 107, 226, 156, 116, 4, 241, 69, 157,
        !            43:   112, 89, 100, 113, 135, 32, 134, 91, 207, 101, 230, 45, 168, 2, 27,
        !            44:   96, 37, 173, 174, 176, 185, 246, 28, 70, 97, 105, 52, 64, 126, 15,
        !            45:   85, 71, 163, 35, 221, 81, 175, 58, 195, 92, 249, 206, 186, 197,
        !            46:   234, 38, 44, 83, 13, 110, 133, 40, 132, 9, 211, 223, 205, 244, 65,
        !            47:   129, 77, 82, 106, 220, 55, 200, 108, 193, 171, 250, 36, 225, 123,
        !            48:   8, 12, 189, 177, 74, 120, 136, 149, 139, 227, 99, 232, 109, 233,
        !            49:   203, 213, 254, 59, 0, 29, 57, 242, 239, 183, 14, 102, 88, 208, 228,
        !            50:   166, 119, 114, 248, 235, 117, 75, 10, 49, 68, 80, 180, 143, 237,
        !            51:   31, 26, 219, 153, 141, 51, 159, 17, 131, 20
        !            52: };
        !            53: 
        !            54: static unsigned char *PADDING[] = {
        !            55:   (unsigned char *)"",
        !            56:   (unsigned char *)"\001",
        !            57:   (unsigned char *)"\002\002",
        !            58:   (unsigned char *)"\003\003\003",
        !            59:   (unsigned char *)"\004\004\004\004",
        !            60:   (unsigned char *)"\005\005\005\005\005",
        !            61:   (unsigned char *)"\006\006\006\006\006\006", 
        !            62:   (unsigned char *)"\007\007\007\007\007\007\007",
        !            63:   (unsigned char *)"\010\010\010\010\010\010\010\010",
        !            64:   (unsigned char *)"\011\011\011\011\011\011\011\011\011",
        !            65:   (unsigned char *)"\012\012\012\012\012\012\012\012\012\012",
        !            66:   (unsigned char *)"\013\013\013\013\013\013\013\013\013\013\013",
        !            67:   (unsigned char *)"\014\014\014\014\014\014\014\014\014\014\014\014",
        !            68:   (unsigned char *)
        !            69:     "\015\015\015\015\015\015\015\015\015\015\015\015\015",
        !            70:   (unsigned char *)
        !            71:     "\016\016\016\016\016\016\016\016\016\016\016\016\016\016",
        !            72:   (unsigned char *)
        !            73:     "\017\017\017\017\017\017\017\017\017\017\017\017\017\017\017",
        !            74:   (unsigned char *)
        !            75:     "\020\020\020\020\020\020\020\020\020\020\020\020\020\020\020\020"
        !            76: };
        !            77: 
        !            78: /* MD2 initialization. Begins an MD2 operation, writing a new context.
        !            79:  */
        !            80: void MD2Init (context)
        !            81: MD2_CTX *context;                                        /* context */
        !            82: {
        !            83:   context->count = 0;
        !            84:   MD2_memset ((POINTER)context->state, 0, sizeof (context->state));
        !            85:   MD2_memset
        !            86:     ((POINTER)context->checksum, 0, sizeof (context->checksum));
        !            87: }
        !            88: 
        !            89: /* MD2 block update operation. Continues an MD2 message-digest
        !            90:      operation, processing another message block, and updating the
        !            91:      context.
        !            92:  */
        !            93: void MD2Update (context, input, inputLen)
        !            94: MD2_CTX *context;                                        /* context */
        !            95: unsigned char *input;                                /* input block */
        !            96: unsigned int inputLen;                     /* length of input block */
        !            97: {
        !            98:   unsigned int i, index, partLen;
        !            99:   
        !           100:   /* Update number of bytes mod 16 */
        !           101:   index = context->count;
        !           102:   context->count = (index + inputLen) & 0xf;
        !           103:   
        !           104:   partLen = 16 - index;
        !           105:   
        !           106:   /* Transform as many times as possible.
        !           107:     */
        !           108:   if (inputLen >= partLen) {
        !           109:     MD2_memcpy
        !           110:       ((POINTER)&context->buffer[index], (POINTER)input, partLen);
        !           111:     MD2Transform (context->state, context->checksum, context->buffer);
        !           112: 
        !           113:     for (i = partLen; i + 15 < inputLen; i += 16)
        !           114:       MD2Transform (context->state, context->checksum, &input[i]);
        !           115:     
        !           116:     index = 0;
        !           117:   }
        !           118:   else
        !           119:     i = 0;
        !           120:   
        !           121:   /* Buffer remaining input */
        !           122:   MD2_memcpy
        !           123:     ((POINTER)&context->buffer[index], (POINTER)&input[i],
        !           124:      inputLen-i);
        !           125: }
        !           126: 
        !           127: /* MD2 finalization. Ends an MD2 message-digest operation, writing the
        !           128:      message digest and zeroizing the context.
        !           129:  */
        !           130: void MD2Final (digest, context)
        !           131: unsigned char digest[16];                         /* message digest */
        !           132: MD2_CTX *context;                                        /* context */
        !           133: {
        !           134:   unsigned int index, padLen;
        !           135: 
        !           136:   /* Pad out to multiple of 16.
        !           137:    */
        !           138:   index = context->count;
        !           139:   padLen = 16 - index;
        !           140:   MD2Update (context, PADDING[padLen], padLen);
        !           141: 
        !           142:   /* Extend with checksum */
        !           143:   MD2Update (context, context->checksum, 16);
        !           144:   
        !           145:   /* Store state in digest */
        !           146:   MD2_memcpy ((POINTER)digest, (POINTER)context->state, 16);
        !           147:   
        !           148:   /* Zeroize sensitive information.
        !           149:    */
        !           150:   MD2_memset ((POINTER)context, 0, sizeof (*context));
        !           151: }
        !           152: 
        !           153: /* MD2 basic transformation. Transforms state and updates checksum
        !           154:      based on block.
        !           155:  */
        !           156: static void MD2Transform (state, checksum, block)
        !           157: unsigned char state[16];
        !           158: unsigned char checksum[16];
        !           159: unsigned char block[16];
        !           160: {
        !           161:   unsigned int i, j, t;
        !           162:   unsigned char x[48];
        !           163:   
        !           164:   /* Form encryption block from state, block, state ^ block.
        !           165:    */
        !           166:   MD2_memcpy ((POINTER)x, (POINTER)state, 16);
        !           167:   MD2_memcpy ((POINTER)x+16, (POINTER)block, 16);
        !           168:   for (i = 0; i < 16; i++)
        !           169:     x[i+32] = state[i] ^ block[i];
        !           170:   
        !           171:   /* Encrypt block (18 rounds).
        !           172:    */
        !           173:   t = 0;
        !           174:   for (i = 0; i < 18; i++) {
        !           175:     for (j = 0; j < 48; j++)
        !           176:       t = x[j] ^= PI_SUBST[t];
        !           177:     t = (t + i) & 0xff;
        !           178:   }
        !           179:     
        !           180:   /* Save new state */
        !           181:   MD2_memcpy ((POINTER)state, (POINTER)x, 16);
        !           182:     
        !           183:   /* Update checksum.
        !           184:    */
        !           185:   t = checksum[15];
        !           186:   for (i = 0; i < 16; i++)
        !           187:     t = checksum[i] ^= PI_SUBST[block[i] ^ t];
        !           188: 
        !           189:   /* Zeroize sensitive information.
        !           190:    */
        !           191:   MD2_memset ((POINTER)x, 0, sizeof (x));
        !           192: }
        !           193: 
        !           194: /* Note: Replace "for loop" with standard memcpy if possible.
        !           195:  */
        !           196: static void MD2_memcpy (output, input, len)
        !           197: POINTER output;
        !           198: POINTER input;
        !           199: unsigned int len;
        !           200: {
        !           201:   unsigned int i;
        !           202:   
        !           203:   for (i = 0; i < len; i++)
        !           204:     output[i] = input[i];
        !           205: }
        !           206: 
        !           207: /* Note: Replace "for loop" with standard memset if possible.
        !           208:  */
        !           209: static void MD2_memset (output, value, len)
        !           210: POINTER output;
        !           211: int value;
        !           212: unsigned int len;
        !           213: {
        !           214:   unsigned int i;
        !           215:   
        !           216:   for (i = 0; i < len; i++)
        !           217:     ((char *)output)[i] = (char)value;
        !           218: }

This archive runs on limited infrastructure. Preserving old code on modern bandwidth. Automated agents are requested to crawl responsibly.