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      1 /*
      2  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
      3  * Use is subject to license terms.
      4  */
      5 
      6 /*
      7  * MD4C.C - RSA Data Security, Inc., MD4 message-digest algorithm
      8  */
      9 
     10 /*
     11  * Copyright (C) 1990-2, RSA Data Security, Inc. All rights reserved.
     12  *
     13  * License to copy and use this software is granted provided that it
     14  * is identified as the "RSA Data Security, Inc. MD4 Message-Digest
     15  * Algorithm" in all material mentioning or referencing this software
     16  * or this function.
     17  *
     18  * License is also granted to make and use derivative works provided
     19  * that such works are identified as "derived from the RSA Data
     20  * Security, Inc. MD4 Message-Digest Algorithm" in all material
     21  * mentioning or referencing the derived work.
     22  *
     23  * RSA Data Security, Inc. makes no representations concerning either
     24  * the merchantability of this software or the suitability of this
     25  * software for any particular purpose. It is provided "as is"
     26  * without express or implied warranty of any kind.
     27  *
     28  * These notices must be retained in any copies of any part of this
     29  * documentation and/or software.
     30  */
     31 
     32 #include <sys/types.h>
     33 #ifdef _KERNEL
     34 #include <sys/sunddi.h>
     35 #else
     36 #include <strings.h>
     37 #endif /* _KERNEL */
     38 
     39 #if defined(__i386) || defined(__amd64)
     40 #define	UNALIGNED_POINTERS_PERMITTED
     41 #endif
     42 
     43 #include <sys/md4.h>
     44 
     45 /*
     46  * Constants for MD4Transform routine.
     47  */
     48 #define	S11 3
     49 #define	S12 7
     50 #define	S13 11
     51 #define	S14 19
     52 #define	S21 3
     53 #define	S22 5
     54 #define	S23 9
     55 #define	S24 13
     56 #define	S31 3
     57 #define	S32 9
     58 #define	S33 11
     59 #define	S34 15
     60 
     61 static void MD4Transform(uint32_t [4], unsigned char [64]);
     62 static void Encode(unsigned char *, uint32_t *, unsigned int);
     63 static void Decode(uint32_t *, unsigned char *, unsigned int);
     64 
     65 static unsigned char PADDING[64] = {
     66 	0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
     67 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
     68 	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
     69 };
     70 
     71 /*
     72  * F, G and H are basic MD4 functions.
     73  */
     74 #define	F(x, y, z) (((x) & (y)) | ((~x) & (z)))
     75 #define	G(x, y, z) (((x) & (y)) | ((x) & (z)) | ((y) & (z)))
     76 #define	H(x, y, z) ((x) ^ (y) ^ (z))
     77 
     78 /*
     79  * ROTATE_LEFT rotates x left n bits.
     80  */
     81 #define	ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32-(n))))
     82 
     83 /* FF, GG and HH are transformations for rounds 1, 2 and 3 */
     84 /* Rotation is separate from addition to prevent recomputation */
     85 
     86 #define	FF(a, b, c, d, x, s) { \
     87 		(a) += F((b), (c), (d)) + (x); \
     88 		(a) = ROTATE_LEFT((a), (s)); \
     89 	}
     90 #define	GG(a, b, c, d, x, s) { \
     91 		(a) += G((b), (c), (d)) + (x) + (uint32_t)0x5a827999; \
     92 		(a) = ROTATE_LEFT((a), (s)); \
     93 	}
     94 #define	HH(a, b, c, d, x, s) { \
     95 		(a) += H((b), (c), (d)) + (x) + (uint32_t)0x6ed9eba1; \
     96 		(a) = ROTATE_LEFT((a), (s)); \
     97 	}
     98 
     99 /*
    100  * MD4 initialization. Begins an MD4 operation, writing a new context.
    101  */
    102 void
    103 MD4Init(MD4_CTX *context)
    104 {
    105 	context->count[0] = context->count[1] = 0;
    106 
    107 	/*
    108 	 * Load magic initialization constants.
    109 	 */
    110 	context->state[0] = 0x67452301UL;
    111 	context->state[1] = 0xefcdab89UL;
    112 	context->state[2] = 0x98badcfeUL;
    113 	context->state[3] = 0x10325476UL;
    114 }
    115 
    116 
    117 /*
    118  * MD4 block update operation. Continues an MD4 message-digest
    119  * operation, processing another message block, and updating the
    120  * context.
    121  */
    122 void
    123 MD4Update(MD4_CTX *context, const void *_RESTRICT_KYWD inptr, size_t inputLen)
    124 {
    125 	unsigned int i, index, partLen;
    126 	uchar_t *input = (uchar_t *)inptr;
    127 
    128 	/* Compute number of bytes mod 64 */
    129 	index = (unsigned int)((context->count[0] >> 3) & 0x3F);
    130 	/* Update number of bits */
    131 	if ((context->count[0] += ((uint32_t)inputLen << 3))
    132 	    < ((uint32_t)inputLen << 3))
    133 		context->count[1]++;
    134 	context->count[1] += ((uint32_t)inputLen >> 29);
    135 
    136 	partLen = 64 - index;
    137 
    138 	/*
    139 	 * Transform as many times as possible.
    140 	 */
    141 	if (inputLen >= partLen) {
    142 		bcopy(input, &context->buffer[index], partLen);
    143 		MD4Transform(context->state, (uchar_t *)context->buffer);
    144 
    145 		for (i = partLen; i + 63 < inputLen; i += 64) {
    146 			MD4Transform(context->state, (uchar_t *)&input[i]);
    147 		}
    148 
    149 		index = 0;
    150 	} else {
    151 		i = 0;
    152 	}
    153 
    154 	/* Buffer remaining input */
    155 	bcopy(&input[i], &context->buffer[index], inputLen - i);
    156 }
    157 
    158 /*
    159  * MD4 finalization. Ends an MD4 message-digest operation, writing the
    160  *	the message digest and zeroizing the context.
    161  */
    162 void
    163 MD4Final(void *digest, MD4_CTX *context)
    164 {
    165 	unsigned char bits[8];
    166 	unsigned int index, padLen;
    167 
    168 	/* Save number of bits */
    169 	Encode(bits, context->count, 8);
    170 
    171 	/*
    172 	 * Pad out to 56 mod 64.
    173 	 */
    174 	index = (unsigned int)((context->count[0] >> 3) & 0x3f);
    175 	padLen = (index < 56) ? (56 - index) : (120 - index);
    176 	MD4Update(context, PADDING, padLen);
    177 
    178 	/* Append length (before padding) */
    179 	MD4Update(context, bits, 8);
    180 	/* Store state in digest */
    181 	Encode(digest, context->state, 16);
    182 
    183 	/* zeroize sensitive information */
    184 	bzero(context, sizeof (*context));
    185 }
    186 
    187 /*
    188  * MD4 basic transformation. Transforms state based on block.
    189  */
    190 static void
    191 MD4Transform(uint32_t state[4], unsigned char block[64])
    192 {
    193 	uint32_t a = state[0], b = state[1], c = state[2], d = state[3], x[16];
    194 
    195 
    196 	Decode(x, block, 64);
    197 
    198 	/* Round 1 */
    199 	FF(a, b, c, d, x[ 0], S11); /* 1 */
    200 	FF(d, a, b, c, x[ 1], S12); /* 2 */
    201 	FF(c, d, a, b, x[ 2], S13); /* 3 */
    202 	FF(b, c, d, a, x[ 3], S14); /* 4 */
    203 	FF(a, b, c, d, x[ 4], S11); /* 5 */
    204 	FF(d, a, b, c, x[ 5], S12); /* 6 */
    205 	FF(c, d, a, b, x[ 6], S13); /* 7 */
    206 	FF(b, c, d, a, x[ 7], S14); /* 8 */
    207 	FF(a, b, c, d, x[ 8], S11); /* 9 */
    208 	FF(d, a, b, c, x[ 9], S12); /* 10 */
    209 	FF(c, d, a, b, x[10], S13); /* 11 */
    210 	FF(b, c, d, a, x[11], S14); /* 12 */
    211 	FF(a, b, c, d, x[12], S11); /* 13 */
    212 	FF(d, a, b, c, x[13], S12); /* 14 */
    213 	FF(c, d, a, b, x[14], S13); /* 15 */
    214 	FF(b, c, d, a, x[15], S14); /* 16 */
    215 
    216 	/* Round 2 */
    217 	GG(a, b, c, d, x[ 0], S21); /* 17 */
    218 	GG(d, a, b, c, x[ 4], S22); /* 18 */
    219 	GG(c, d, a, b, x[ 8], S23); /* 19 */
    220 	GG(b, c, d, a, x[12], S24); /* 20 */
    221 	GG(a, b, c, d, x[ 1], S21); /* 21 */
    222 	GG(d, a, b, c, x[ 5], S22); /* 22 */
    223 	GG(c, d, a, b, x[ 9], S23); /* 23 */
    224 	GG(b, c, d, a, x[13], S24); /* 24 */
    225 	GG(a, b, c, d, x[ 2], S21); /* 25 */
    226 	GG(d, a, b, c, x[ 6], S22); /* 26 */
    227 	GG(c, d, a, b, x[10], S23); /* 27 */
    228 	GG(b, c, d, a, x[14], S24); /* 28 */
    229 	GG(a, b, c, d, x[ 3], S21); /* 29 */
    230 	GG(d, a, b, c, x[ 7], S22); /* 30 */
    231 	GG(c, d, a, b, x[11], S23); /* 31 */
    232 	GG(b, c, d, a, x[15], S24); /* 32 */
    233 
    234 
    235 	/* Round 3 */
    236 	HH(a, b, c, d, x[ 0], S31); /* 33 */
    237 	HH(d, a, b, c, x[ 8], S32); /* 34 */
    238 	HH(c, d, a, b, x[ 4], S33); /* 35 */
    239 	HH(b, c, d, a, x[12], S34); /* 36 */
    240 	HH(a, b, c, d, x[ 2], S31); /* 37 */
    241 	HH(d, a, b, c, x[10], S32); /* 38 */
    242 	HH(c, d, a, b, x[ 6], S33); /* 39 */
    243 	HH(b, c, d, a, x[14], S34); /* 40 */
    244 	HH(a, b, c, d, x[ 1], S31); /* 41 */
    245 	HH(d, a, b, c, x[ 9], S32); /* 42 */
    246 	HH(c, d, a, b, x[ 5], S33); /* 43 */
    247 	HH(b, c, d, a, x[13], S34); /* 44 */
    248 	HH(a, b, c, d, x[ 3], S31); /* 45 */
    249 	HH(d, a, b, c, x[11], S32); /* 46 */
    250 	HH(c, d, a, b, x[ 7], S33); /* 47 */
    251 	HH(b, c, d, a, x[15], S34); /* 48 */
    252 
    253 	state[0] += a;
    254 	state[1] += b;
    255 	state[2] += c;
    256 	state[3] += d;
    257 
    258 	/* zeroize sensitive information */
    259 	bzero(x, sizeof (*x));
    260 }
    261 
    262 /*
    263  * Encodes input (uint32_t) into output (unsigned char). Assumes len is
    264  * a multiple of 4.
    265  */
    266 static void
    267 Encode(unsigned char *output, uint32_t *input, unsigned int len)
    268 {
    269 	unsigned int i, j;
    270 
    271 	for (i = 0, j = 0; j < len; i++, j += 4) {
    272 #if defined(_LITTLE_ENDIAN) && defined(UNALIGNED_POINTERS_PERMITTED)
    273 		*(uint32_t *)(void *)&output[j] = input[i];
    274 #else
    275 		/* endian-independent code */
    276 		output[j] = (unsigned char)(input[i] & 0xff);
    277 		output[j+1] = (unsigned char)((input[i] >> 8) & 0xff);
    278 		output[j+2] = (unsigned char)((input[i] >> 16) & 0xff);
    279 		output[j+3] = (unsigned char)((input[i] >> 24) & 0xff);
    280 #endif	/* _LITTLE_ENDIAN && UNALIGNED_POINTERS_PERMITTED */
    281 	}
    282 }
    283 
    284 /*
    285  * Decodes input (unsigned char) into output (uint32_t). Assumes len is
    286  * a multiple of 4.
    287  */
    288 static void
    289 Decode(uint32_t *output, unsigned char *input, unsigned int len)
    290 {
    291 	unsigned int i, j;
    292 
    293 	for (i = 0, j = 0; j < len; i++, j += 4) {
    294 #if defined(_LITTLE_ENDIAN) && defined(UNALIGNED_POINTERS_PERMITTED)
    295 		output[i] = *(uint32_t *)(void *)&input[j];
    296 #else
    297 		/* endian-independent code */
    298 		output[i] = ((uint32_t)input[j]) |
    299 		    (((uint32_t)input[j+1]) << 8) |
    300 		    (((uint32_t)input[j+2]) << 16) |
    301 		    (((uint32_t)input[j+3]) << 24);
    302 #endif	/* _LITTLE_ENDIAN && UNALIGNED_POINTERS_PERMITTED */
    303 	}
    304 
    305 }
    306