Quake-2

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md4.c (9487B)


      1 /* GLOBAL.H - RSAREF types and constants */
      2 
      3 #include <string.h>
      4 
      5 /* POINTER defines a generic pointer type */
      6 typedef unsigned char *POINTER;
      7 
      8 /* UINT2 defines a two byte word */
      9 typedef unsigned short int UINT2;
     10 
     11 /* UINT4 defines a four byte word */
     12 #ifdef __alpha__
     13 typedef unsigned int UINT4;
     14 #else
     15 typedef unsigned long int UINT4;
     16 #endif
     17 
     18   
     19 /* MD4.H - header file for MD4C.C */
     20 
     21 /* Copyright (C) 1991-2, RSA Data Security, Inc. Created 1991. 
     22 
     23 All rights reserved.
     24   
     25 License to copy and use this software is granted provided that it is identified as the “RSA Data Security, Inc. MD4 Message-Digest Algorithm” in all material mentioning or referencing this software or this function.
     26 License is also granted to make and use derivative works provided that such works are identified as “derived from the RSA Data Security, Inc. MD4 Message-Digest Algorithm” in all material mentioning or referencing the derived work.
     27 RSA Data Security, Inc. makes no representations concerning either the merchantability of this software or the suitability of this software for any particular purpose. It is provided “as is” without express or implied warranty of any kind.
     28   
     29 These notices must be retained in any copies of any part of this documentation and/or software. */
     30 
     31 /* MD4 context. */
     32 typedef struct {
     33 	UINT4 state[4];				/* state (ABCD) */
     34 	UINT4 count[2];				/* number of bits, modulo 2^64 (lsb first) */
     35 	unsigned char buffer[64]; 			/* input buffer */
     36 } MD4_CTX;
     37 
     38 void MD4Init (MD4_CTX *);
     39 void MD4Update (MD4_CTX *, unsigned char *, unsigned int);
     40 void MD4Final (unsigned char [16], MD4_CTX *);
     41   
     42 
     43   
     44 /* MD4C.C - RSA Data Security, Inc., MD4 message-digest algorithm */
     45 /* Copyright (C) 1990-2, RSA Data Security, Inc. All rights reserved.
     46   
     47 License to copy and use this software is granted provided that it is identified as the
     48 RSA Data Security, Inc. MD4 Message-Digest Algorithm
     49  in all material mentioning or referencing this software or this function.
     50 License is also granted to make and use derivative works provided that such works are identified as 
     51 derived from the RSA Data Security, Inc. MD4 Message-Digest Algorithm
     52 in all material mentioning or referencing the derived work.
     53 RSA Data Security, Inc. makes no representations concerning either the merchantability of this software or the suitability of this software for any particular purpose. It is provided
     54 as is without express or implied warranty of any kind.
     55   
     56 These notices must be retained in any copies of any part of this documentation and/or software. */
     57 
     58 /* Constants for MD4Transform routine.  */
     59 #define S11 3
     60 #define S12 7
     61 #define S13 11
     62 #define S14 19
     63 #define S21 3
     64 #define S22 5
     65 #define S23 9
     66 #define S24 13
     67 #define S31 3
     68 #define S32 9
     69 #define S33 11
     70 #define S34 15
     71 
     72 static void MD4Transform (UINT4 [4], unsigned char [64]);
     73 static void Encode (unsigned char *, UINT4 *, unsigned int);
     74 static void Decode (UINT4 *, unsigned char *, unsigned int);
     75 
     76 static unsigned char PADDING[64] = {
     77 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
     78 };
     79 
     80 /* F, G and H are basic MD4 functions. */
     81 #define F(x, y, z) (((x) & (y)) | ((~x) & (z)))
     82 #define G(x, y, z) (((x) & (y)) | ((x) & (z)) | ((y) & (z)))
     83 #define H(x, y, z) ((x) ^ (y) ^ (z))
     84 
     85 /* ROTATE_LEFT rotates x left n bits. */
     86 #define ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32-(n))))
     87 
     88 /* FF, GG and HH are transformations for rounds 1, 2 and 3 */
     89 /* Rotation is separate from addition to prevent recomputation */
     90 #define FF(a, b, c, d, x, s) {(a) += F ((b), (c), (d)) + (x); (a) = ROTATE_LEFT ((a), (s));}
     91 
     92 #define GG(a, b, c, d, x, s) {(a) += G ((b), (c), (d)) + (x) + (UINT4)0x5a827999; (a) = ROTATE_LEFT ((a), (s));}
     93 
     94 #define HH(a, b, c, d, x, s) {(a) += H ((b), (c), (d)) + (x) + (UINT4)0x6ed9eba1; (a) = ROTATE_LEFT ((a), (s));}
     95 
     96 
     97 /* MD4 initialization. Begins an MD4 operation, writing a new context. */
     98 void MD4Init (MD4_CTX *context)
     99 {
    100 	context->count[0] = context->count[1] = 0;
    101 
    102 /* Load magic initialization constants.*/
    103 context->state[0] = 0x67452301;
    104 context->state[1] = 0xefcdab89;
    105 context->state[2] = 0x98badcfe;
    106 context->state[3] = 0x10325476;
    107 }
    108 
    109 /* MD4 block update operation. Continues an MD4 message-digest operation, processing another message block, and updating the context. */
    110 void MD4Update (MD4_CTX *context, unsigned char *input, unsigned int inputLen)
    111 {
    112 	unsigned int i, index, partLen;
    113 
    114 	/* Compute number of bytes mod 64 */
    115 	index = (unsigned int)((context->count[0] >> 3) & 0x3F);
    116 
    117 	/* Update number of bits */
    118 	if ((context->count[0] += ((UINT4)inputLen << 3))< ((UINT4)inputLen << 3))
    119 		context->count[1]++;
    120 
    121 	context->count[1] += ((UINT4)inputLen >> 29);
    122 
    123 	partLen = 64 - index;
    124 
    125 	/* Transform as many times as possible.*/
    126 	if (inputLen >= partLen)
    127 	{
    128  		memcpy((POINTER)&context->buffer[index], (POINTER)input, partLen);
    129  		MD4Transform (context->state, context->buffer);
    130 
    131  		for (i = partLen; i + 63 < inputLen; i += 64)
    132  			MD4Transform (context->state, &input[i]);
    133 
    134  		index = 0;
    135 	}
    136 	else
    137  		i = 0;
    138 
    139 	/* Buffer remaining input */
    140 	memcpy ((POINTER)&context->buffer[index], (POINTER)&input[i], inputLen-i);
    141 }
    142 
    143 
    144 /* MD4 finalization. Ends an MD4 message-digest operation, writing the the message digest and zeroizing the context. */
    145 void MD4Final (unsigned char digest[16], MD4_CTX *context)
    146 {
    147 	unsigned char bits[8];
    148 	unsigned int index, padLen;
    149 
    150 	/* Save number of bits */
    151 	Encode (bits, context->count, 8);
    152 
    153 	/* Pad out to 56 mod 64.*/
    154 	index = (unsigned int)((context->count[0] >> 3) & 0x3f);
    155 	padLen = (index < 56) ? (56 - index) : (120 - index);
    156 	MD4Update (context, PADDING, padLen);
    157 
    158 	/* Append length (before padding) */
    159 	MD4Update (context, bits, 8);
    160 	
    161 	/* Store state in digest */
    162 	Encode (digest, context->state, 16);
    163 
    164 	/* Zeroize sensitive information.*/
    165 	memset ((POINTER)context, 0, sizeof (*context));
    166 }
    167 
    168 
    169 /* MD4 basic transformation. Transforms state based on block. */
    170 static void MD4Transform (UINT4 state[4], unsigned char block[64])
    171 {
    172 	UINT4 a = state[0], b = state[1], c = state[2], d = state[3], x[16];
    173 
    174 	Decode (x, block, 64);
    175 
    176 /* Round 1 */
    177 FF (a, b, c, d, x[ 0], S11); 				/* 1 */
    178 FF (d, a, b, c, x[ 1], S12); 				/* 2 */
    179 FF (c, d, a, b, x[ 2], S13); 				/* 3 */
    180 FF (b, c, d, a, x[ 3], S14); 				/* 4 */
    181 FF (a, b, c, d, x[ 4], S11); 				/* 5 */
    182 FF (d, a, b, c, x[ 5], S12); 				/* 6 */
    183 FF (c, d, a, b, x[ 6], S13); 				/* 7 */
    184 FF (b, c, d, a, x[ 7], S14); 				/* 8 */
    185 FF (a, b, c, d, x[ 8], S11); 				/* 9 */
    186 FF (d, a, b, c, x[ 9], S12); 				/* 10 */
    187 FF (c, d, a, b, x[10], S13); 			/* 11 */
    188 FF (b, c, d, a, x[11], S14); 			/* 12 */
    189 FF (a, b, c, d, x[12], S11); 			/* 13 */
    190 FF (d, a, b, c, x[13], S12); 			/* 14 */
    191 FF (c, d, a, b, x[14], S13); 			/* 15 */
    192 FF (b, c, d, a, x[15], S14); 			/* 16 */
    193 
    194 /* Round 2 */
    195 GG (a, b, c, d, x[ 0], S21); 			/* 17 */
    196 GG (d, a, b, c, x[ 4], S22); 			/* 18 */
    197 GG (c, d, a, b, x[ 8], S23); 			/* 19 */
    198 GG (b, c, d, a, x[12], S24); 			/* 20 */
    199 GG (a, b, c, d, x[ 1], S21); 			/* 21 */
    200 GG (d, a, b, c, x[ 5], S22); 			/* 22 */
    201 GG (c, d, a, b, x[ 9], S23); 			/* 23 */
    202 GG (b, c, d, a, x[13], S24); 			/* 24 */
    203 GG (a, b, c, d, x[ 2], S21); 			/* 25 */
    204 GG (d, a, b, c, x[ 6], S22); 			/* 26 */
    205 GG (c, d, a, b, x[10], S23); 			/* 27 */
    206 GG (b, c, d, a, x[14], S24); 			/* 28 */
    207 GG (a, b, c, d, x[ 3], S21); 			/* 29 */
    208 GG (d, a, b, c, x[ 7], S22); 			/* 30 */
    209 GG (c, d, a, b, x[11], S23); 			/* 31 */
    210 GG (b, c, d, a, x[15], S24); 			/* 32 */
    211 
    212 /* Round 3 */
    213 HH (a, b, c, d, x[ 0], S31);				/* 33 */
    214 HH (d, a, b, c, x[ 8], S32); 			/* 34 */
    215 HH (c, d, a, b, x[ 4], S33); 			/* 35 */
    216 HH (b, c, d, a, x[12], S34); 			/* 36 */
    217 HH (a, b, c, d, x[ 2], S31); 			/* 37 */
    218 HH (d, a, b, c, x[10], S32); 			/* 38 */
    219 HH (c, d, a, b, x[ 6], S33); 			/* 39 */
    220 HH (b, c, d, a, x[14], S34); 			/* 40 */
    221 HH (a, b, c, d, x[ 1], S31); 			/* 41 */
    222 HH (d, a, b, c, x[ 9], S32); 			/* 42 */
    223 HH (c, d, a, b, x[ 5], S33); 			/* 43 */
    224 HH (b, c, d, a, x[13], S34); 			/* 44 */
    225 HH (a, b, c, d, x[ 3], S31); 			/* 45 */
    226 HH (d, a, b, c, x[11], S32); 			/* 46 */
    227 HH (c, d, a, b, x[ 7], S33); 			/* 47 */
    228 HH (b, c, d, a, x[15], S34);			/* 48 */
    229 
    230 state[0] += a;
    231 state[1] += b;
    232 state[2] += c;
    233 state[3] += d;
    234 
    235 	/* Zeroize sensitive information.*/
    236 	memset ((POINTER)x, 0, sizeof (x));
    237 }
    238 
    239 
    240 /* Encodes input (UINT4) into output (unsigned char). Assumes len is a multiple of 4. */
    241 static void Encode (unsigned char *output, UINT4 *input, unsigned int len)
    242 {
    243 	unsigned int i, j;
    244 
    245 	for (i = 0, j = 0; j < len; i++, j += 4) {
    246  		output[j] = (unsigned char)(input[i] & 0xff);
    247  		output[j+1] = (unsigned char)((input[i] >> 8) & 0xff);
    248  		output[j+2] = (unsigned char)((input[i] >> 16) & 0xff);
    249  		output[j+3] = (unsigned char)((input[i] >> 24) & 0xff);
    250 	}
    251 }
    252 
    253 
    254 /* Decodes input (unsigned char) into output (UINT4). Assumes len is a multiple of 4. */
    255 static void Decode (UINT4 *output, unsigned char *input, unsigned int len)
    256 {
    257 unsigned int i, j;
    258 
    259 for (i = 0, j = 0; j < len; i++, j += 4)
    260  	output[i] = ((UINT4)input[j]) | (((UINT4)input[j+1]) << 8) | (((UINT4)input[j+2]) << 16) | (((UINT4)input[j+3]) << 24);
    261 }
    262 
    263 //===================================================================
    264 
    265 unsigned Com_BlockChecksum (void *buffer, int length)
    266 {
    267 	int			digest[4];
    268 	unsigned	val;
    269 	MD4_CTX		ctx;
    270 
    271 	MD4Init (&ctx);
    272 	MD4Update (&ctx, (unsigned char *)buffer, length);
    273 	MD4Final ( (unsigned char *)digest, &ctx);
    274 	
    275 	val = digest[0] ^ digest[1] ^ digest[2] ^ digest[3];
    276 
    277 	return val;
    278 }