[libfaim.git] / src / 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

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