[libfaim.git] / md5.c

/*
  Copyright (C) 1999 Aladdin Enterprises.  All rights reserved.

  This software is provided 'as-is', without any express or implied
  warranty.  In no event will the authors be held liable for any damages
  arising from the use of this software.

  Permission is granted to anyone to use this software for any purpose,
  including commercial applications, and to alter it and redistribute it
  freely, subject to the following restrictions:

  1. The origin of this software must not be misrepresented; you must not
     claim that you wrote the original software. If you use this software
     in a product, an acknowledgment in the product documentation would be
     appreciated but is not required.
  2. Altered source versions must be plainly marked as such, and must not be
     misrepresented as being the original software.
  3. This notice may not be removed or altered from any source distribution.

  L. Peter Deutsch
  ghost@aladdin.com

 */
/*$Id$ */
/*
  Independent implementation of MD5 (RFC 1321).

  This code implements the MD5 Algorithm defined in RFC 1321.
  It is derived directly from the text of the RFC and not from the
  reference implementation.

  The original and principal author of md5.c is L. Peter Deutsch
  <ghost@aladdin.com>.  Other authors are noted in the change history
  that follows (in reverse chronological order):

  1999-11-04 lpd Edited comments slightly for automatic TOC extraction.
  1999-10-18 lpd Fixed typo in header comment (ansi2knr rather than md5).
  1999-05-03 lpd Original version.
 */

#include "md5.h"
#include <string.h>

#ifdef TEST
/*
 * Compile with -DTEST to create a self-contained executable test program.
 * The test program should print out the same values as given in section
 * A.5 of RFC 1321, reproduced below.
 */
#include <string.h>
main()
{
    static const char *const test[7] = {
	"", /*d41d8cd98f00b204e9800998ecf8427e*/
	"945399884.61923487334tuvga", /*0cc175b9c0f1b6a831c399e269772661*/
	"abc", /*900150983cd24fb0d6963f7d28e17f72*/
	"message digest", /*f96b697d7cb7938d525a2f31aaf161d0*/
	"abcdefghijklmnopqrstuvwxyz", /*c3fcd3d76192e4007dfb496cca67e13b*/
	"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789",
				/*d174ab98d277d9f5a5611c2c9f419d9f*/
	"12345678901234567890123456789012345678901234567890123456789012345678901234567890" /*57edf4a22be3c955ac49da2e2107b67a*/
    };
    int i;

    for (i = 0; i < 7; ++i) {
	md5_state_t state;
	md5_byte_t digest[16];
	int di;

	md5_init(&state);
	md5_append(&state, (const md5_byte_t *)test[i], strlen(test[i]));
	md5_finish(&state, digest);
	printf("MD5 (\"%s\") = ", test[i]);
	for (di = 0; di < 16; ++di)
	    printf("%02x", digest[di]);
	printf("\n");
    }
    return 0;
}
#endif /* TEST */


/*
 * For reference, here is the program that computed the T values.
 */
#if 0
#include <math.h>
main()
{
    int i;
    for (i = 1; i <= 64; ++i) {
	unsigned long v = (unsigned long)(4294967296.0 * fabs(sin((double)i)));
	printf("#define T%d 0x%08lx\n", i, v);
    }
    return 0;
}
#endif
/*
 * End of T computation program.
 */
#define T1 0xd76aa478
#define T2 0xe8c7b756
#define T3 0x242070db
#define T4 0xc1bdceee
#define T5 0xf57c0faf
#define T6 0x4787c62a
#define T7 0xa8304613
#define T8 0xfd469501
#define T9 0x698098d8
#define T10 0x8b44f7af
#define T11 0xffff5bb1
#define T12 0x895cd7be
#define T13 0x6b901122
#define T14 0xfd987193
#define T15 0xa679438e
#define T16 0x49b40821
#define T17 0xf61e2562
#define T18 0xc040b340
#define T19 0x265e5a51
#define T20 0xe9b6c7aa
#define T21 0xd62f105d
#define T22 0x02441453
#define T23 0xd8a1e681
#define T24 0xe7d3fbc8
#define T25 0x21e1cde6
#define T26 0xc33707d6
#define T27 0xf4d50d87
#define T28 0x455a14ed
#define T29 0xa9e3e905
#define T30 0xfcefa3f8
#define T31 0x676f02d9
#define T32 0x8d2a4c8a
#define T33 0xfffa3942
#define T34 0x8771f681
#define T35 0x6d9d6122
#define T36 0xfde5380c
#define T37 0xa4beea44
#define T38 0x4bdecfa9
#define T39 0xf6bb4b60
#define T40 0xbebfbc70
#define T41 0x289b7ec6
#define T42 0xeaa127fa
#define T43 0xd4ef3085
#define T44 0x04881d05
#define T45 0xd9d4d039
#define T46 0xe6db99e5
#define T47 0x1fa27cf8
#define T48 0xc4ac5665
#define T49 0xf4292244
#define T50 0x432aff97
#define T51 0xab9423a7
#define T52 0xfc93a039
#define T53 0x655b59c3
#define T54 0x8f0ccc92
#define T55 0xffeff47d
#define T56 0x85845dd1
#define T57 0x6fa87e4f
#define T58 0xfe2ce6e0
#define T59 0xa3014314
#define T60 0x4e0811a1
#define T61 0xf7537e82
#define T62 0xbd3af235
#define T63 0x2ad7d2bb
#define T64 0xeb86d391

static void
md5_process(md5_state_t *pms, const md5_byte_t *data /*[64]*/)
{
    md5_word_t
	a = pms->abcd[0], b = pms->abcd[1],
	c = pms->abcd[2], d = pms->abcd[3];
    md5_word_t t;

#ifndef ARCH_IS_BIG_ENDIAN
# define ARCH_IS_BIG_ENDIAN 1	/* slower, default implementation */
#endif
#if ARCH_IS_BIG_ENDIAN

    /*
     * On big-endian machines, we must arrange the bytes in the right
     * order.  (This also works on machines of unknown byte order.)
     */
    md5_word_t X[16];
    const md5_byte_t *xp = data;
    int i;

    for (i = 0; i < 16; ++i, xp += 4)
	X[i] = xp[0] + (xp[1] << 8) + (xp[2] << 16) + (xp[3] << 24);

#else  /* !ARCH_IS_BIG_ENDIAN */

    /*
     * On little-endian machines, we can process properly aligned data
     * without copying it.
     */
    md5_word_t xbuf[16];
    const md5_word_t *X;

    if (!((data - (const md5_byte_t *)0) & 3)) {
	/* data are properly aligned */
	X = (const md5_word_t *)data;
    } else {
	/* not aligned */
	memcpy(xbuf, data, 64);
	X = xbuf;
    }
#endif

#define ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32 - (n))))

    /* Round 1. */
    /* Let [abcd k s i] denote the operation
       a = b + ((a + F(b,c,d) + X[k] + T[i]) <<< s). */
#define F(x, y, z) (((x) & (y)) | (~(x) & (z)))
#define SET(a, b, c, d, k, s, Ti)\
  t = a + F(b,c,d) + X[k] + Ti;\
  a = ROTATE_LEFT(t, s) + b
    /* Do the following 16 operations. */
    SET(a, b, c, d,  0,  7,  T1);
    SET(d, a, b, c,  1, 12,  T2);
    SET(c, d, a, b,  2, 17,  T3);
    SET(b, c, d, a,  3, 22,  T4);
    SET(a, b, c, d,  4,  7,  T5);
    SET(d, a, b, c,  5, 12,  T6);
    SET(c, d, a, b,  6, 17,  T7);
    SET(b, c, d, a,  7, 22,  T8);
    SET(a, b, c, d,  8,  7,  T9);
    SET(d, a, b, c,  9, 12, T10);
    SET(c, d, a, b, 10, 17, T11);
    SET(b, c, d, a, 11, 22, T12);
    SET(a, b, c, d, 12,  7, T13);
    SET(d, a, b, c, 13, 12, T14);
    SET(c, d, a, b, 14, 17, T15);
    SET(b, c, d, a, 15, 22, T16);
#undef SET

     /* Round 2. */
     /* Let [abcd k s i] denote the operation
          a = b + ((a + G(b,c,d) + X[k] + T[i]) <<< s). */
#define G(x, y, z) (((x) & (z)) | ((y) & ~(z)))
#define SET(a, b, c, d, k, s, Ti)\
  t = a + G(b,c,d) + X[k] + Ti;\
  a = ROTATE_LEFT(t, s) + b
     /* Do the following 16 operations. */
    SET(a, b, c, d,  1,  5, T17);
    SET(d, a, b, c,  6,  9, T18);
    SET(c, d, a, b, 11, 14, T19);
    SET(b, c, d, a,  0, 20, T20);
    SET(a, b, c, d,  5,  5, T21);
    SET(d, a, b, c, 10,  9, T22);
    SET(c, d, a, b, 15, 14, T23);
    SET(b, c, d, a,  4, 20, T24);
    SET(a, b, c, d,  9,  5, T25);
    SET(d, a, b, c, 14,  9, T26);
    SET(c, d, a, b,  3, 14, T27);
    SET(b, c, d, a,  8, 20, T28);
    SET(a, b, c, d, 13,  5, T29);
    SET(d, a, b, c,  2,  9, T30);
    SET(c, d, a, b,  7, 14, T31);
    SET(b, c, d, a, 12, 20, T32);
#undef SET

     /* Round 3. */
     /* Let [abcd k s t] denote the operation
          a = b + ((a + H(b,c,d) + X[k] + T[i]) <<< s). */
#define H(x, y, z) ((x) ^ (y) ^ (z))
#define SET(a, b, c, d, k, s, Ti)\
  t = a + H(b,c,d) + X[k] + Ti;\
  a = ROTATE_LEFT(t, s) + b
     /* Do the following 16 operations. */
    SET(a, b, c, d,  5,  4, T33);
    SET(d, a, b, c,  8, 11, T34);
    SET(c, d, a, b, 11, 16, T35);
    SET(b, c, d, a, 14, 23, T36);
    SET(a, b, c, d,  1,  4, T37);
    SET(d, a, b, c,  4, 11, T38);
    SET(c, d, a, b,  7, 16, T39);
    SET(b, c, d, a, 10, 23, T40);
    SET(a, b, c, d, 13,  4, T41);
    SET(d, a, b, c,  0, 11, T42);
    SET(c, d, a, b,  3, 16, T43);
    SET(b, c, d, a,  6, 23, T44);
    SET(a, b, c, d,  9,  4, T45);
    SET(d, a, b, c, 12, 11, T46);
    SET(c, d, a, b, 15, 16, T47);
    SET(b, c, d, a,  2, 23, T48);
#undef SET

     /* Round 4. */
     /* Let [abcd k s t] denote the operation
          a = b + ((a + I(b,c,d) + X[k] + T[i]) <<< s). */
#define I(x, y, z) ((y) ^ ((x) | ~(z)))
#define SET(a, b, c, d, k, s, Ti)\
  t = a + I(b,c,d) + X[k] + Ti;\
  a = ROTATE_LEFT(t, s) + b
     /* Do the following 16 operations. */
    SET(a, b, c, d,  0,  6, T49);
    SET(d, a, b, c,  7, 10, T50);
    SET(c, d, a, b, 14, 15, T51);
    SET(b, c, d, a,  5, 21, T52);
    SET(a, b, c, d, 12,  6, T53);
    SET(d, a, b, c,  3, 10, T54);
    SET(c, d, a, b, 10, 15, T55);
    SET(b, c, d, a,  1, 21, T56);
    SET(a, b, c, d,  8,  6, T57);
    SET(d, a, b, c, 15, 10, T58);
    SET(c, d, a, b,  6, 15, T59);
    SET(b, c, d, a, 13, 21, T60);
    SET(a, b, c, d,  4,  6, T61);
    SET(d, a, b, c, 11, 10, T62);
    SET(c, d, a, b,  2, 15, T63);
    SET(b, c, d, a,  9, 21, T64);
#undef SET

     /* Then perform the following additions. (That is increment each
        of the four registers by the value it had before this block
        was started.) */
    pms->abcd[0] += a;
    pms->abcd[1] += b;
    pms->abcd[2] += c;
    pms->abcd[3] += d;
}

void
md5_init(md5_state_t *pms)
{
    pms->count[0] = pms->count[1] = 0;
    pms->abcd[0] = 0x67452301;
    pms->abcd[1] = 0xefcdab89;
    pms->abcd[2] = 0x98badcfe;
    pms->abcd[3] = 0x10325476;
}

void
md5_append(md5_state_t *pms, const md5_byte_t *data, int nbytes)
{
    const md5_byte_t *p = data;
    int left = nbytes;
    int offset = (pms->count[0] >> 3) & 63;
    md5_word_t nbits = (md5_word_t)(nbytes << 3);

    if (nbytes <= 0)
	return;

    /* Update the message length. */
    pms->count[1] += nbytes >> 29;
    pms->count[0] += nbits;
    if (pms->count[0] < nbits)
	pms->count[1]++;

    /* Process an initial partial block. */
    if (offset) {
	int copy = (offset + nbytes > 64 ? 64 - offset : nbytes);

	memcpy(pms->buf + offset, p, copy);
	if (offset + copy < 64)
	    return;
	p += copy;
	left -= copy;
	md5_process(pms, pms->buf);
    }

    /* Process full blocks. */
    for (; left >= 64; p += 64, left -= 64)
	md5_process(pms, p);

    /* Process a final partial block. */
    if (left)
	memcpy(pms->buf, p, left);
}

void
md5_finish(md5_state_t *pms, md5_byte_t digest[16])
{
    static const md5_byte_t pad[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
    };
    md5_byte_t data[8];
    int i;

    /* Save the length before padding. */
    for (i = 0; i < 8; ++i)
	data[i] = (md5_byte_t)(pms->count[i >> 2] >> ((i & 3) << 3));
    /* Pad to 56 bytes mod 64. */
    md5_append(pms, pad, ((55 - (pms->count[0] >> 3)) & 63) + 1);
    /* Append the length. */
    md5_append(pms, data, 8);
    for (i = 0; i < 16; ++i)
	digest[i] = (md5_byte_t)(pms->abcd[i >> 2] >> ((i & 3) << 3));
}
Commit	Line	Data
b5bc2a8c	1	/*
	2	Copyright (C) 1999 Aladdin Enterprises. All rights reserved.
	3
	4	This software is provided 'as-is', without any express or implied
	5	warranty. In no event will the authors be held liable for any damages
	6	arising from the use of this software.
	7
	8	Permission is granted to anyone to use this software for any purpose,
	9	including commercial applications, and to alter it and redistribute it
	10	freely, subject to the following restrictions:
	11
	12	1. The origin of this software must not be misrepresented; you must not
	13	claim that you wrote the original software. If you use this software
	14	in a product, an acknowledgment in the product documentation would be
	15	appreciated but is not required.
	16	2. Altered source versions must be plainly marked as such, and must not be
	17	misrepresented as being the original software.
	18	3. This notice may not be removed or altered from any source distribution.
	19
	20	L. Peter Deutsch
	21	ghost@aladdin.com
	22
	23	*/
	24	/$Id$ /
	25	/*
	26	Independent implementation of MD5 (RFC 1321).
	27
	28	This code implements the MD5 Algorithm defined in RFC 1321.
	29	It is derived directly from the text of the RFC and not from the
	30	reference implementation.
	31
	32	The original and principal author of md5.c is L. Peter Deutsch
	33	<ghost@aladdin.com>. Other authors are noted in the change history
	34	that follows (in reverse chronological order):
	35
	36	1999-11-04 lpd Edited comments slightly for automatic TOC extraction.
	37	1999-10-18 lpd Fixed typo in header comment (ansi2knr rather than md5).
	38	1999-05-03 lpd Original version.
	39	*/
	40
	41	#include "md5.h"
5ac21963	42	#include <string.h>
b5bc2a8c	43
	44	#ifdef TEST
	45	/*
	46	* Compile with -DTEST to create a self-contained executable test program.
	47	* The test program should print out the same values as given in section
	48	* A.5 of RFC 1321, reproduced below.
	49	*/
	50	#include <string.h>
	51	main()
	52	{
	53	static const char *const test[7] = {
	54	"", /d41d8cd98f00b204e9800998ecf8427e/
	55	"945399884.61923487334tuvga", /0cc175b9c0f1b6a831c399e269772661/
	56	"abc", /900150983cd24fb0d6963f7d28e17f72/
	57	"message digest", /f96b697d7cb7938d525a2f31aaf161d0/
	58	"abcdefghijklmnopqrstuvwxyz", /c3fcd3d76192e4007dfb496cca67e13b/
	59	"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789",
	60	/d174ab98d277d9f5a5611c2c9f419d9f/
	61	"12345678901234567890123456789012345678901234567890123456789012345678901234567890" /57edf4a22be3c955ac49da2e2107b67a/
	62	};
	63	int i;
	64
	65	for (i = 0; i < 7; ++i) {
	66	md5_state_t state;
	67	md5_byte_t digest[16];
	68	int di;
	69
	70	md5_init(&state);
	71	md5_append(&state, (const md5_byte_t *)test[i], strlen(test[i]));
	72	md5_finish(&state, digest);
	73	printf("MD5 (\"%s\") = ", test[i]);
	74	for (di = 0; di < 16; ++di)
	75	printf("%02x", digest[di]);
	76	printf("\n");
	77	}
	78	return 0;
	79	}
	80	#endif /* TEST */
	81
	82
	83	/*
	84	* For reference, here is the program that computed the T values.
	85	*/
	86	#if 0
	87	#include <math.h>
	88	main()
	89	{
	90	int i;
	91	for (i = 1; i <= 64; ++i) {
	92	unsigned long v = (unsigned long)(4294967296.0 * fabs(sin((double)i)));
	93	printf("#define T%d 0x%08lx\n", i, v);
	94	}
	95	return 0;
	96	}
	97	#endif
	98	/*
	99	* End of T computation program.
	100	*/
	101	#define T1 0xd76aa478
	102	#define T2 0xe8c7b756
	103	#define T3 0x242070db
	104	#define T4 0xc1bdceee
	105	#define T5 0xf57c0faf
	106	#define T6 0x4787c62a
107	#define T7 0xa8304613
108	#define T8 0xfd469501
109	#define T9 0x698098d8
110	#define T10 0x8b44f7af
111	#define T11 0xffff5bb1
112	#define T12 0x895cd7be
113	#define T13 0x6b901122
114	#define T14 0xfd987193
115	#define T15 0xa679438e
116	#define T16 0x49b40821
117	#define T17 0xf61e2562
118	#define T18 0xc040b340
119	#define T19 0x265e5a51
120	#define T20 0xe9b6c7aa
121	#define T21 0xd62f105d
122	#define T22 0x02441453
123	#define T23 0xd8a1e681
124	#define T24 0xe7d3fbc8
125	#define T25 0x21e1cde6
126	#define T26 0xc33707d6
127	#define T27 0xf4d50d87
128	#define T28 0x455a14ed
129	#define T29 0xa9e3e905
130	#define T30 0xfcefa3f8
131	#define T31 0x676f02d9
132	#define T32 0x8d2a4c8a
133	#define T33 0xfffa3942
134	#define T34 0x8771f681
135	#define T35 0x6d9d6122
136	#define T36 0xfde5380c
137	#define T37 0xa4beea44
138	#define T38 0x4bdecfa9
139	#define T39 0xf6bb4b60
140	#define T40 0xbebfbc70
141	#define T41 0x289b7ec6
142	#define T42 0xeaa127fa
143	#define T43 0xd4ef3085
144	#define T44 0x04881d05
145	#define T45 0xd9d4d039
146	#define T46 0xe6db99e5
147	#define T47 0x1fa27cf8
148	#define T48 0xc4ac5665
149	#define T49 0xf4292244
150	#define T50 0x432aff97
151	#define T51 0xab9423a7
152	#define T52 0xfc93a039
153	#define T53 0x655b59c3
154	#define T54 0x8f0ccc92
155	#define T55 0xffeff47d
156	#define T56 0x85845dd1
157	#define T57 0x6fa87e4f
158	#define T58 0xfe2ce6e0
159	#define T59 0xa3014314
160	#define T60 0x4e0811a1
161	#define T61 0xf7537e82
162	#define T62 0xbd3af235
163	#define T63 0x2ad7d2bb
164	#define T64 0xeb86d391
165
166	static void
167	md5_process(md5_state_t pms, const md5_byte_t data /[64]/)
168	{
169	md5_word_t
170	a = pms->abcd[0], b = pms->abcd[1],
171	c = pms->abcd[2], d = pms->abcd[3];
172	md5_word_t t;
173
174	#ifndef ARCH_IS_BIG_ENDIAN
175	# define ARCH_IS_BIG_ENDIAN 1 /* slower, default implementation */
176	#endif
177	#if ARCH_IS_BIG_ENDIAN
178
179	/*
180	* On big-endian machines, we must arrange the bytes in the right
181	* order. (This also works on machines of unknown byte order.)
182	*/
183	md5_word_t X[16];
184	const md5_byte_t *xp = data;
185	int i;
186
187	for (i = 0; i < 16; ++i, xp += 4)
188	X[i] = xp[0] + (xp[1] << 8) + (xp[2] << 16) + (xp[3] << 24);
189
190	#else /* !ARCH_IS_BIG_ENDIAN */
191
192	/*
193	* On little-endian machines, we can process properly aligned data
194	* without copying it.
195	*/
196	md5_word_t xbuf[16];
197	const md5_word_t *X;
198
199	if (!((data - (const md5_byte_t *)0) & 3)) {
200	/* data are properly aligned */
201	X = (const md5_word_t *)data;
202	} else {
203	/* not aligned */
204	memcpy(xbuf, data, 64);
205	X = xbuf;
206	}
207	#endif
208
209	#define ROTATE_LEFT(x, n) (((x) << (n)) \| ((x) >> (32 - (n))))
210
211	/* Round 1. */
212	/* Let [abcd k s i] denote the operation
213	a = b + ((a + F(b,c,d) + X[k] + T[i]) <<< s). */
214	#define F(x, y, z) (((x) & (y)) \| (~(x) & (z)))
215	#define SET(a, b, c, d, k, s, Ti)\
216	t = a + F(b,c,d) + X[k] + Ti;\
217	a = ROTATE_LEFT(t, s) + b
218	/* Do the following 16 operations. */
219	SET(a, b, c, d, 0, 7, T1);
220	SET(d, a, b, c, 1, 12, T2);
221	SET(c, d, a, b, 2, 17, T3);
222	SET(b, c, d, a, 3, 22, T4);
223	SET(a, b, c, d, 4, 7, T5);
224	SET(d, a, b, c, 5, 12, T6);
225	SET(c, d, a, b, 6, 17, T7);
226	SET(b, c, d, a, 7, 22, T8);
227	SET(a, b, c, d, 8, 7, T9);
228	SET(d, a, b, c, 9, 12, T10);
229	SET(c, d, a, b, 10, 17, T11);
230	SET(b, c, d, a, 11, 22, T12);
231	SET(a, b, c, d, 12, 7, T13);
232	SET(d, a, b, c, 13, 12, T14);
233	SET(c, d, a, b, 14, 17, T15);
234	SET(b, c, d, a, 15, 22, T16);
235	#undef SET
236
237	/* Round 2. */
238	/* Let [abcd k s i] denote the operation
239	a = b + ((a + G(b,c,d) + X[k] + T[i]) <<< s). */
240	#define G(x, y, z) (((x) & (z)) \| ((y) & ~(z)))
241	#define SET(a, b, c, d, k, s, Ti)\
242	t = a + G(b,c,d) + X[k] + Ti;\
243	a = ROTATE_LEFT(t, s) + b
244	/* Do the following 16 operations. */
245	SET(a, b, c, d, 1, 5, T17);
246	SET(d, a, b, c, 6, 9, T18);
247	SET(c, d, a, b, 11, 14, T19);
248	SET(b, c, d, a, 0, 20, T20);
249	SET(a, b, c, d, 5, 5, T21);
250	SET(d, a, b, c, 10, 9, T22);
251	SET(c, d, a, b, 15, 14, T23);
252	SET(b, c, d, a, 4, 20, T24);
253	SET(a, b, c, d, 9, 5, T25);
254	SET(d, a, b, c, 14, 9, T26);
255	SET(c, d, a, b, 3, 14, T27);
256	SET(b, c, d, a, 8, 20, T28);
257	SET(a, b, c, d, 13, 5, T29);
258	SET(d, a, b, c, 2, 9, T30);
259	SET(c, d, a, b, 7, 14, T31);
260	SET(b, c, d, a, 12, 20, T32);
261	#undef SET
262
263	/* Round 3. */
264	/* Let [abcd k s t] denote the operation
265	a = b + ((a + H(b,c,d) + X[k] + T[i]) <<< s). */
266	#define H(x, y, z) ((x) ^ (y) ^ (z))
267	#define SET(a, b, c, d, k, s, Ti)\
268	t = a + H(b,c,d) + X[k] + Ti;\
269	a = ROTATE_LEFT(t, s) + b
270	/* Do the following 16 operations. */
271	SET(a, b, c, d, 5, 4, T33);
272	SET(d, a, b, c, 8, 11, T34);
273	SET(c, d, a, b, 11, 16, T35);
274	SET(b, c, d, a, 14, 23, T36);
275	SET(a, b, c, d, 1, 4, T37);
276	SET(d, a, b, c, 4, 11, T38);
277	SET(c, d, a, b, 7, 16, T39);
278	SET(b, c, d, a, 10, 23, T40);
279	SET(a, b, c, d, 13, 4, T41);
280	SET(d, a, b, c, 0, 11, T42);
281	SET(c, d, a, b, 3, 16, T43);
282	SET(b, c, d, a, 6, 23, T44);
283	SET(a, b, c, d, 9, 4, T45);
284	SET(d, a, b, c, 12, 11, T46);
285	SET(c, d, a, b, 15, 16, T47);
286	SET(b, c, d, a, 2, 23, T48);
287	#undef SET
288
289	/* Round 4. */
290	/* Let [abcd k s t] denote the operation
291	a = b + ((a + I(b,c,d) + X[k] + T[i]) <<< s). */
292	#define I(x, y, z) ((y) ^ ((x) \| ~(z)))
293	#define SET(a, b, c, d, k, s, Ti)\
294	t = a + I(b,c,d) + X[k] + Ti;\
295	a = ROTATE_LEFT(t, s) + b
296	/* Do the following 16 operations. */
297	SET(a, b, c, d, 0, 6, T49);
298	SET(d, a, b, c, 7, 10, T50);
299	SET(c, d, a, b, 14, 15, T51);
300	SET(b, c, d, a, 5, 21, T52);
301	SET(a, b, c, d, 12, 6, T53);
302	SET(d, a, b, c, 3, 10, T54);
303	SET(c, d, a, b, 10, 15, T55);
304	SET(b, c, d, a, 1, 21, T56);
305	SET(a, b, c, d, 8, 6, T57);
306	SET(d, a, b, c, 15, 10, T58);
307	SET(c, d, a, b, 6, 15, T59);
308	SET(b, c, d, a, 13, 21, T60);
309	SET(a, b, c, d, 4, 6, T61);
310	SET(d, a, b, c, 11, 10, T62);
311	SET(c, d, a, b, 2, 15, T63);
312	SET(b, c, d, a, 9, 21, T64);
313	#undef SET
314
315	/* Then perform the following additions. (That is increment each
316	of the four registers by the value it had before this block
317	was started.) */
318	pms->abcd[0] += a;
319	pms->abcd[1] += b;
320	pms->abcd[2] += c;
321	pms->abcd[3] += d;
322	}
323
324	void
325	md5_init(md5_state_t *pms)
326	{
327	pms->count[0] = pms->count[1] = 0;
328	pms->abcd[0] = 0x67452301;
329	pms->abcd[1] = 0xefcdab89;
330	pms->abcd[2] = 0x98badcfe;
331	pms->abcd[3] = 0x10325476;
332	}
333
334	void
335	md5_append(md5_state_t pms, const md5_byte_t data, int nbytes)
336	{
337	const md5_byte_t *p = data;
338	int left = nbytes;
339	int offset = (pms->count[0] >> 3) & 63;
340	md5_word_t nbits = (md5_word_t)(nbytes << 3);
341
342	if (nbytes <= 0)
343	return;
344
345	/* Update the message length. */
346	pms->count[1] += nbytes >> 29;
347	pms->count[0] += nbits;
348	if (pms->count[0] < nbits)
349	pms->count[1]++;
350
351	/* Process an initial partial block. */
352	if (offset) {
353	int copy = (offset + nbytes > 64 ? 64 - offset : nbytes);
354
355	memcpy(pms->buf + offset, p, copy);
356	if (offset + copy < 64)
357	return;
358	p += copy;
359	left -= copy;
360	md5_process(pms, pms->buf);
361	}
362
363	/* Process full blocks. */
364	for (; left >= 64; p += 64, left -= 64)
365	md5_process(pms, p);
366
367	/* Process a final partial block. */
368	if (left)
369	memcpy(pms->buf, p, left);
370	}
371
372	void
373	md5_finish(md5_state_t *pms, md5_byte_t digest[16])
374	{
375	static const md5_byte_t pad[64] = {
376	0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
377	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
378	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
379	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
380	};
381	md5_byte_t data[8];
382	int i;
383
384	/* Save the length before padding. */
385	for (i = 0; i < 8; ++i)
386	data[i] = (md5_byte_t)(pms->count[i >> 2] >> ((i & 3) << 3));
387	/* Pad to 56 bytes mod 64. */
388	md5_append(pms, pad, ((55 - (pms->count[0] >> 3)) & 63) + 1);
389	/* Append the length. */
390	md5_append(pms, data, 8);
391	for (i = 0; i < 16; ++i)
392	digest[i] = (md5_byte_t)(pms->abcd[i >> 2] >> ((i & 3) << 3));
393	}