libbb/pw_encrypt_md5.c - busybox - Git at Google

 /*
  * MD5C.C - RSA Data Security, Inc., MD5 message-digest algorithm
  *
  * Copyright (C) 1991-2, RSA Data Security, Inc. Created 1991. All
  * rights reserved.
  *
  * License to copy and use this software is granted provided that it
  * is identified as the "RSA Data Security, Inc. MD5 Message-Digest
  * Algorithm" in all material mentioning or referencing this software
  * or this function.
  *
  * License is also granted to make and use derivative works provided
  * that such works are identified as "derived from the RSA Data
  * Security, Inc. MD5 Message-Digest Algorithm" in all material
  * mentioning or referencing the derived work.
  *
  * 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.
  *
  * These notices must be retained in any copies of any part of this
  * documentation and/or software.
  *
  * $FreeBSD: src/lib/libmd/md5c.c,v 1.9.2.1 1999/08/29 14:57:12 peter Exp $
  *
  * This code is the same as the code published by RSA Inc.  It has been
  * edited for clarity and style only.
  *
  * ----------------------------------------------------------------------------
  * The md5_crypt() function was taken from freeBSD's libcrypt and contains
  * this license:
  *    "THE BEER-WARE LICENSE" (Revision 42):
  *     <phk@login.dknet.dk> wrote this file.  As long as you retain this notice you
  *     can do whatever you want with this stuff. If we meet some day, and you think
  *     this stuff is worth it, you can buy me a beer in return.   Poul-Henning Kamp
  *
  * $FreeBSD: src/lib/libcrypt/crypt.c,v 1.7.2.1 1999/08/29 14:56:33 peter Exp $
  *
  * ----------------------------------------------------------------------------
  * On April 19th, 2001 md5_crypt() was modified to make it reentrant
  * by Erik Andersen <andersen@uclibc.org>
  *
  *
  * June 28, 2001             Manuel Novoa III
  *
  * "Un-inlined" code using loops and static const tables in order to
  * reduce generated code size (on i386 from approx 4k to approx 2.5k).
  *
  * June 29, 2001             Manuel Novoa III
  *
  * Completely removed static PADDING array.
  *
  * Reintroduced the loop unrolling in MD5_Transform and added the
  * MD5_SIZE_OVER_SPEED option for configurability.  Define below as:
  *       0    fully unrolled loops
  *       1    partially unrolled (4 ops per loop)
  *       2    no unrolling -- introduces the need to swap 4 variables (slow)
  *       3    no unrolling and all 4 loops merged into one with switch
  *               in each loop (glacial)
  * On i386, sizes are roughly (-Os -fno-builtin):
  *     0: 3k     1: 2.5k     2: 2.2k     3: 2k
  *
  *
  * Since SuSv3 does not require crypt_r, modified again August 7, 2002
  * by Erik Andersen to remove reentrance stuff...
  */

 /*
  * Valid values are  1 (fastest/largest) to 3 (smallest/slowest).
  */
 #define MD5_SIZE_OVER_SPEED 3

 /**********************************************************************/

 /* MD5 context. */
 struct MD5Context {
 	uint32_t state[4];	/* state (ABCD) */
 	uint32_t count[2];	/* number of bits, modulo 2^64 (lsb first) */
 	unsigned char buffer[64];	/* input buffer */
 };

 static void __md5_Init(struct MD5Context *);
 static void __md5_Update(struct MD5Context *, const unsigned char *, unsigned int);
 static void __md5_Pad(struct MD5Context *);
 static void __md5_Final(unsigned char [16], struct MD5Context *);
 static void __md5_Transform(uint32_t [4], const unsigned char [64]);


 #define MD5_MAGIC_STR "$1$"
 #define MD5_MAGIC_LEN (sizeof(MD5_MAGIC_STR) - 1)
 static const unsigned char __md5__magic[] = MD5_MAGIC_STR;


 #ifdef i386
 #define __md5_Encode memcpy
 #define __md5_Decode memcpy
 #else /* i386 */

 /*
  * __md5_Encodes input (uint32_t) into output (unsigned char). Assumes len is
  * a multiple of 4.
  */
 static void
 __md5_Encode(unsigned char *output, uint32_t *input, unsigned int len)
 {
 	unsigned int i, j;

 	for (i = 0, j = 0; j < len; i++, j += 4) {
 		output[j] = input[i];
 		output[j+1] = (input[i] >> 8);
 		output[j+2] = (input[i] >> 16);
 		output[j+3] = (input[i] >> 24);
 	}
 }

 /*
  * __md5_Decodes input (unsigned char) into output (uint32_t). Assumes len is
  * a multiple of 4.
  */
 static void
 __md5_Decode(uint32_t *output, const unsigned char *input, unsigned int len)
 {
 	unsigned int i, j;

 	for (i = 0, j = 0; j < len; i++, j += 4)
 		output[i] = ((uint32_t)input[j]) | (((uint32_t)input[j+1]) << 8) |
 		    (((uint32_t)input[j+2]) << 16) | (((uint32_t)input[j+3]) << 24);
 }
 #endif /* i386 */

 /* F, G, H and I are basic MD5 functions. */
 #define F(x, y, z) (((x) & (y)) | (~(x) & (z)))
 #define G(x, y, z) (((x) & (z)) | ((y) & ~(z)))
 #define H(x, y, z) ((x) ^ (y) ^ (z))
 #define I(x, y, z) ((y) ^ ((x) | ~(z)))

 /* ROTATE_LEFT rotates x left n bits. */
 #define ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32-(n))))

 /*
  * FF, GG, HH, and II transformations for rounds 1, 2, 3, and 4.
  * Rotation is separate from addition to prevent recomputation.
  */
 #define FF(a, b, c, d, x, s, ac) { \
 	(a) += F ((b), (c), (d)) + (x) + (uint32_t)(ac); \
 	(a) = ROTATE_LEFT((a), (s)); \
 	(a) += (b); \
 	}
 #define GG(a, b, c, d, x, s, ac) { \
 	(a) += G ((b), (c), (d)) + (x) + (uint32_t)(ac); \
 	(a) = ROTATE_LEFT((a), (s)); \
 	(a) += (b); \
 	}
 #define HH(a, b, c, d, x, s, ac) { \
 	(a) += H ((b), (c), (d)) + (x) + (uint32_t)(ac); \
 	(a) = ROTATE_LEFT((a), (s)); \
 	(a) += (b); \
 	}
 #define II(a, b, c, d, x, s, ac) { \
 	(a) += I ((b), (c), (d)) + (x) + (uint32_t)(ac); \
 	(a) = ROTATE_LEFT((a), (s)); \
 	(a) += (b); \
 	}

 /* MD5 initialization. Begins an MD5 operation, writing a new context. */
 static void __md5_Init(struct MD5Context *context)
 {
 	context->count[0] = context->count[1] = 0;

 	/* Load magic initialization constants.  */
 	context->state[0] = 0x67452301;
 	context->state[1] = 0xefcdab89;
 	context->state[2] = 0x98badcfe;
 	context->state[3] = 0x10325476;
 }

 /*
  * MD5 block update operation. Continues an MD5 message-digest
  * operation, processing another message block, and updating the
  * context.
  */
 static void __md5_Update(struct MD5Context *context, const unsigned char *input, unsigned int inputLen)
 {
 	unsigned int i, idx, partLen;

 	/* Compute number of bytes mod 64 */
 	idx = (context->count[0] >> 3) & 0x3F;

 	/* Update number of bits */
 	context->count[0] += (inputLen << 3);
 	if (context->count[0] < (inputLen << 3))
 		context->count[1]++;
 	context->count[1] += (inputLen >> 29);

 	partLen = 64 - idx;

 	/* Transform as many times as possible. */
 	if (inputLen >= partLen) {
 		memcpy(&context->buffer[idx], input, partLen);
 		__md5_Transform(context->state, context->buffer);

 		for (i = partLen; i + 63 < inputLen; i += 64)
 			__md5_Transform(context->state, &input[i]);

 		idx = 0;
 	} else
 		i = 0;

 	/* Buffer remaining input */
 	memcpy(&context->buffer[idx], &input[i], inputLen - i);
 }

 /*
  * MD5 padding. Adds padding followed by original length.
  */
 static void __md5_Pad(struct MD5Context *context)
 {
 	unsigned char bits[8];
 	unsigned int idx, padLen;
 	unsigned char PADDING[64];

 	memset(PADDING, 0, sizeof(PADDING));
 	PADDING[0] = 0x80;

 	/* Save number of bits */
 	__md5_Encode(bits, context->count, 8);

 	/* Pad out to 56 mod 64. */
 	idx = (context->count[0] >> 3) & 0x3f;
 	padLen = (idx < 56) ? (56 - idx) : (120 - idx);
 	__md5_Update(context, PADDING, padLen);

 	/* Append length (before padding) */
 	__md5_Update(context, bits, 8);
 }

 /*
  * MD5 finalization. Ends an MD5 message-digest operation, writing the
  * the message digest and zeroizing the context.
  */
 static void __md5_Final(unsigned char digest[16], struct MD5Context *context)
 {
 	/* Do padding. */
 	__md5_Pad(context);

 	/* Store state in digest */
 	__md5_Encode(digest, context->state, 16);

 	/* Zeroize sensitive information. */
 	memset(context, 0, sizeof(*context));
 }

 /* MD5 basic transformation. Transforms state based on block. */
 static void __md5_Transform(uint32_t state[4], const unsigned char block[64])
 {
 	uint32_t a, b, c, d, x[16];
 #if MD5_SIZE_OVER_SPEED > 1
 	uint32_t temp;
 	const unsigned char *ps;

 	static const unsigned char S[] = {
 		7, 12, 17, 22,
 		5, 9, 14, 20,
 		4, 11, 16, 23,
 		6, 10, 15, 21
 	};
 #endif /* MD5_SIZE_OVER_SPEED > 1 */

 #if MD5_SIZE_OVER_SPEED > 0
 	const uint32_t *pc;
 	const unsigned char *pp;
 	int i;

 	static const uint32_t C[] = {
 								/* round 1 */
 		0xd76aa478, 0xe8c7b756, 0x242070db, 0xc1bdceee,
 		0xf57c0faf, 0x4787c62a, 0xa8304613, 0xfd469501,
 		0x698098d8, 0x8b44f7af, 0xffff5bb1, 0x895cd7be,
 		0x6b901122, 0xfd987193, 0xa679438e, 0x49b40821,
 								/* round 2 */
 		0xf61e2562, 0xc040b340, 0x265e5a51, 0xe9b6c7aa,
 		0xd62f105d, 0x2441453,  0xd8a1e681, 0xe7d3fbc8,
 		0x21e1cde6, 0xc33707d6, 0xf4d50d87, 0x455a14ed,
 		0xa9e3e905, 0xfcefa3f8, 0x676f02d9, 0x8d2a4c8a,
 								/* round 3 */
 		0xfffa3942, 0x8771f681, 0x6d9d6122, 0xfde5380c,
 		0xa4beea44, 0x4bdecfa9, 0xf6bb4b60, 0xbebfbc70,
 		0x289b7ec6, 0xeaa127fa, 0xd4ef3085, 0x4881d05,
 		0xd9d4d039, 0xe6db99e5, 0x1fa27cf8, 0xc4ac5665,
 								/* round 4 */
 		0xf4292244, 0x432aff97, 0xab9423a7, 0xfc93a039,
 		0x655b59c3, 0x8f0ccc92, 0xffeff47d, 0x85845dd1,
 		0x6fa87e4f, 0xfe2ce6e0, 0xa3014314, 0x4e0811a1,
 		0xf7537e82, 0xbd3af235, 0x2ad7d2bb, 0xeb86d391
 	};

 	static const unsigned char P[] = {
 		0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, /* 1 */
 		1, 6, 11, 0, 5, 10, 15, 4, 9, 14, 3, 8, 13, 2, 7, 12, /* 2 */
 		5, 8, 11, 14, 1, 4, 7, 10, 13, 0, 3, 6, 9, 12, 15, 2, /* 3 */
 		0, 7, 14, 5, 12, 3, 10, 1, 8, 15, 6, 13, 4, 11, 2, 9  /* 4 */
 	};

 #endif /* MD5_SIZE_OVER_SPEED > 0 */

 	__md5_Decode(x, block, 64);

 	a = state[0]; b = state[1]; c = state[2]; d = state[3];

 #if MD5_SIZE_OVER_SPEED > 2
 	pc = C; pp = P; ps = S - 4;

 	for (i = 0; i < 64; i++) {
 		if ((i & 0x0f) == 0) ps += 4;
 		temp = a;
 		switch (i>>4) {
 			case 0:
 				temp += F(b, c, d);
 				break;
 			case 1:
 				temp += G(b, c, d);
 				break;
 			case 2:
 				temp += H(b, c, d);
 				break;
 			case 3:
 				temp += I(b, c, d);
 				break;
 		}
 		temp += x[*pp++] + *pc++;
 		temp = ROTATE_LEFT(temp, ps[i & 3]);
 		temp += b;
 		a = d; d = c; c = b; b = temp;
 	}
 #elif MD5_SIZE_OVER_SPEED > 1
 	pc = C; pp = P; ps = S;

 	/* Round 1 */
 	for (i = 0; i < 16; i++) {
 		FF(a, b, c, d, x[*pp], ps[i & 0x3], *pc); pp++; pc++;
 		temp = d; d = c; c = b; b = a; a = temp;
 	}

 	/* Round 2 */
 	ps += 4;
 	for (; i < 32; i++) {
 		GG(a, b, c, d, x[*pp], ps[i & 0x3], *pc); pp++; pc++;
 		temp = d; d = c; c = b; b = a; a = temp;
 	}
 	/* Round 3 */
 	ps += 4;
 	for (; i < 48; i++) {
 		HH(a, b, c, d, x[*pp], ps[i & 0x3], *pc); pp++; pc++;
 		temp = d; d = c; c = b; b = a; a = temp;
 	}

 	/* Round 4 */
 	ps += 4;
 	for (; i < 64; i++) {
 		II(a, b, c, d, x[*pp], ps[i & 0x3], *pc); pp++; pc++;
 		temp = d; d = c; c = b; b = a; a = temp;
 	}
 #elif MD5_SIZE_OVER_SPEED > 0
 	pc = C; pp = P;

 	/* Round 1 */
 	for (i = 0; i < 4; i++) {
 		FF(a, b, c, d, x[*pp],  7, *pc); pp++; pc++;
 		FF(d, a, b, c, x[*pp], 12, *pc); pp++; pc++;
 		FF(c, d, a, b, x[*pp], 17, *pc); pp++; pc++;
 		FF(b, c, d, a, x[*pp], 22, *pc); pp++; pc++;
 	}

 	/* Round 2 */
 	for (i = 0; i < 4; i++) {
 		GG(a, b, c, d, x[*pp],  5, *pc); pp++; pc++;
 		GG(d, a, b, c, x[*pp],  9, *pc); pp++; pc++;
 		GG(c, d, a, b, x[*pp], 14, *pc); pp++; pc++;
 		GG(b, c, d, a, x[*pp], 20, *pc); pp++; pc++;
 	}
 	/* Round 3 */
 	for (i = 0; i < 4; i++) {
 		HH(a, b, c, d, x[*pp],  4, *pc); pp++; pc++;
 		HH(d, a, b, c, x[*pp], 11, *pc); pp++; pc++;
 		HH(c, d, a, b, x[*pp], 16, *pc); pp++; pc++;
 		HH(b, c, d, a, x[*pp], 23, *pc); pp++; pc++;
 	}

 	/* Round 4 */
 	for (i = 0; i < 4; i++) {
 		II(a, b, c, d, x[*pp],  6, *pc); pp++; pc++;
 		II(d, a, b, c, x[*pp], 10, *pc); pp++; pc++;
 		II(c, d, a, b, x[*pp], 15, *pc); pp++; pc++;
 		II(b, c, d, a, x[*pp], 21, *pc); pp++; pc++;
 	}
 #else
 	/* Round 1 */
 #define S11 7
 #define S12 12
 #define S13 17
 #define S14 22
 	FF(a, b, c, d, x[ 0], S11, 0xd76aa478); /* 1 */
 	FF(d, a, b, c, x[ 1], S12, 0xe8c7b756); /* 2 */
 	FF(c, d, a, b, x[ 2], S13, 0x242070db); /* 3 */
 	FF(b, c, d, a, x[ 3], S14, 0xc1bdceee); /* 4 */
 	FF(a, b, c, d, x[ 4], S11, 0xf57c0faf); /* 5 */
 	FF(d, a, b, c, x[ 5], S12, 0x4787c62a); /* 6 */
 	FF(c, d, a, b, x[ 6], S13, 0xa8304613); /* 7 */
 	FF(b, c, d, a, x[ 7], S14, 0xfd469501); /* 8 */
 	FF(a, b, c, d, x[ 8], S11, 0x698098d8); /* 9 */
 	FF(d, a, b, c, x[ 9], S12, 0x8b44f7af); /* 10 */
 	FF(c, d, a, b, x[10], S13, 0xffff5bb1); /* 11 */
 	FF(b, c, d, a, x[11], S14, 0x895cd7be); /* 12 */
 	FF(a, b, c, d, x[12], S11, 0x6b901122); /* 13 */
 	FF(d, a, b, c, x[13], S12, 0xfd987193); /* 14 */
 	FF(c, d, a, b, x[14], S13, 0xa679438e); /* 15 */
 	FF(b, c, d, a, x[15], S14, 0x49b40821); /* 16 */

 	/* Round 2 */
 #define S21 5
 #define S22 9
 #define S23 14
 #define S24 20
 	GG(a, b, c, d, x[ 1], S21, 0xf61e2562); /* 17 */
 	GG(d, a, b, c, x[ 6], S22, 0xc040b340); /* 18 */
 	GG(c, d, a, b, x[11], S23, 0x265e5a51); /* 19 */
 	GG(b, c, d, a, x[ 0], S24, 0xe9b6c7aa); /* 20 */
 	GG(a, b, c, d, x[ 5], S21, 0xd62f105d); /* 21 */
 	GG(d, a, b, c, x[10], S22,  0x2441453); /* 22 */
 	GG(c, d, a, b, x[15], S23, 0xd8a1e681); /* 23 */
 	GG(b, c, d, a, x[ 4], S24, 0xe7d3fbc8); /* 24 */
 	GG(a, b, c, d, x[ 9], S21, 0x21e1cde6); /* 25 */
 	GG(d, a, b, c, x[14], S22, 0xc33707d6); /* 26 */
 	GG(c, d, a, b, x[ 3], S23, 0xf4d50d87); /* 27 */
 	GG(b, c, d, a, x[ 8], S24, 0x455a14ed); /* 28 */
 	GG(a, b, c, d, x[13], S21, 0xa9e3e905); /* 29 */
 	GG(d, a, b, c, x[ 2], S22, 0xfcefa3f8); /* 30 */
 	GG(c, d, a, b, x[ 7], S23, 0x676f02d9); /* 31 */
 	GG(b, c, d, a, x[12], S24, 0x8d2a4c8a); /* 32 */

 	/* Round 3 */
 #define S31 4
 #define S32 11
 #define S33 16
 #define S34 23
 	HH(a, b, c, d, x[ 5], S31, 0xfffa3942); /* 33 */
 	HH(d, a, b, c, x[ 8], S32, 0x8771f681); /* 34 */
 	HH(c, d, a, b, x[11], S33, 0x6d9d6122); /* 35 */
 	HH(b, c, d, a, x[14], S34, 0xfde5380c); /* 36 */
 	HH(a, b, c, d, x[ 1], S31, 0xa4beea44); /* 37 */
 	HH(d, a, b, c, x[ 4], S32, 0x4bdecfa9); /* 38 */
 	HH(c, d, a, b, x[ 7], S33, 0xf6bb4b60); /* 39 */
 	HH(b, c, d, a, x[10], S34, 0xbebfbc70); /* 40 */
 	HH(a, b, c, d, x[13], S31, 0x289b7ec6); /* 41 */
 	HH(d, a, b, c, x[ 0], S32, 0xeaa127fa); /* 42 */
 	HH(c, d, a, b, x[ 3], S33, 0xd4ef3085); /* 43 */
 	HH(b, c, d, a, x[ 6], S34,  0x4881d05); /* 44 */
 	HH(a, b, c, d, x[ 9], S31, 0xd9d4d039); /* 45 */
 	HH(d, a, b, c, x[12], S32, 0xe6db99e5); /* 46 */
 	HH(c, d, a, b, x[15], S33, 0x1fa27cf8); /* 47 */
 	HH(b, c, d, a, x[ 2], S34, 0xc4ac5665); /* 48 */

 	/* Round 4 */
 #define S41 6
 #define S42 10
 #define S43 15
 #define S44 21
 	II(a, b, c, d, x[ 0], S41, 0xf4292244); /* 49 */
 	II(d, a, b, c, x[ 7], S42, 0x432aff97); /* 50 */
 	II(c, d, a, b, x[14], S43, 0xab9423a7); /* 51 */
 	II(b, c, d, a, x[ 5], S44, 0xfc93a039); /* 52 */
 	II(a, b, c, d, x[12], S41, 0x655b59c3); /* 53 */
 	II(d, a, b, c, x[ 3], S42, 0x8f0ccc92); /* 54 */
 	II(c, d, a, b, x[10], S43, 0xffeff47d); /* 55 */
 	II(b, c, d, a, x[ 1], S44, 0x85845dd1); /* 56 */
 	II(a, b, c, d, x[ 8], S41, 0x6fa87e4f); /* 57 */
 	II(d, a, b, c, x[15], S42, 0xfe2ce6e0); /* 58 */
 	II(c, d, a, b, x[ 6], S43, 0xa3014314); /* 59 */
 	II(b, c, d, a, x[13], S44, 0x4e0811a1); /* 60 */
 	II(a, b, c, d, x[ 4], S41, 0xf7537e82); /* 61 */
 	II(d, a, b, c, x[11], S42, 0xbd3af235); /* 62 */
 	II(c, d, a, b, x[ 2], S43, 0x2ad7d2bb); /* 63 */
 	II(b, c, d, a, x[ 9], S44, 0xeb86d391); /* 64 */
 #endif

 	state[0] += a;
 	state[1] += b;
 	state[2] += c;
 	state[3] += d;

 	/* Zeroize sensitive information. */
 	memset(x, 0, sizeof(x));
 }


 static char*
 __md5_to64(char *s, unsigned v, int n)
 {
 	while (--n >= 0) {
 		*s++ = ascii64[v & 0x3f];
 		v >>= 6;
 	}
 	return s;
 }

 /*
  * UNIX password
  *
  * Use MD5 for what it is best at...
  */
 #define MD5_OUT_BUFSIZE 36
 static char *
 NOINLINE
 md5_crypt(char passwd[MD5_OUT_BUFSIZE], const unsigned char *pw, const unsigned char *salt)
 {
 	const unsigned char *sp, *ep;
 	char *p;
 	unsigned char final[17];	/* final[16] exists only to aid in looping */
 	int sl, pl, i, pw_len;
 	struct MD5Context ctx, ctx1;

 	/* Refine the Salt first */
 	sp = salt;

 // always true for bbox
 //	/* If it starts with the magic string, then skip that */
 //	if (!strncmp(sp, __md5__magic, MD5_MAGIC_LEN))
 		sp += MD5_MAGIC_LEN;

 	/* It stops at the first '$', max 8 chars */
 	for (ep = sp; *ep && *ep != '$' && ep < (sp+8); ep++)
 		continue;

 	/* get the length of the true salt */
 	sl = ep - sp;

 	__md5_Init(&ctx);

 	/* The password first, since that is what is most unknown */
 	pw_len = strlen((char*)pw);
 	__md5_Update(&ctx, pw, pw_len);

 	/* Then our magic string */
 	__md5_Update(&ctx, __md5__magic, MD5_MAGIC_LEN);

 	/* Then the raw salt */
 	__md5_Update(&ctx, sp, sl);

 	/* Then just as many characters of the MD5(pw, salt, pw) */
 	__md5_Init(&ctx1);
 	__md5_Update(&ctx1, pw, pw_len);
 	__md5_Update(&ctx1, sp, sl);
 	__md5_Update(&ctx1, pw, pw_len);
 	__md5_Final(final, &ctx1);
 	for (pl = pw_len; pl > 0; pl -= 16)
 		__md5_Update(&ctx, final, pl > 16 ? 16 : pl);

 	/* Don't leave anything around in vm they could use. */
 //TODO: the above comment seems to be wrong. final is used later.
 	memset(final, 0, sizeof(final));

 	/* Then something really weird... */
 	for (i = pw_len; i; i >>= 1) {
 		__md5_Update(&ctx, ((i & 1) ? final : (const unsigned char *) pw), 1);
 	}

 	/* Now make the output string */
 	passwd[0] = '$';
 	passwd[1] = '1';
 	passwd[2] = '$';
 	strncpy(passwd + 3, (char*)sp, sl);
 	passwd[sl + 3] = '$';

 	__md5_Final(final, &ctx);

 	/*
 	 * and now, just to make sure things don't run too fast
 	 * On a 60 Mhz Pentium this takes 34 msec, so you would
 	 * need 30 seconds to build a 1000 entry dictionary...
 	 */
 	for (i = 0; i < 1000; i++) {
 		__md5_Init(&ctx1);
 		if (i & 1)
 			__md5_Update(&ctx1, pw, pw_len);
 		else
 			__md5_Update(&ctx1, final, 16);

 		if (i % 3)
 			__md5_Update(&ctx1, sp, sl);

 		if (i % 7)
 			__md5_Update(&ctx1, pw, pw_len);

 		if (i & 1)
 			__md5_Update(&ctx1, final, 16);
 		else
 			__md5_Update(&ctx1, pw, pw_len);
 		__md5_Final(final, &ctx1);
 	}

 	p = passwd + sl + 4; /* 12 bytes max (sl is up to 8 bytes) */

 	/* Add 5*4+2 = 22 bytes of hash, + NUL byte. */
 	final[16] = final[5];
 	for (i = 0; i < 5; i++) {
 		unsigned l = (final[i] << 16) | (final[i+6] << 8) | final[i+12];
 		p = __md5_to64(p, l, 4);
 	}
 	p = __md5_to64(p, final[11], 2);
 	*p = '\0';

 	/* Don't leave anything around in vm they could use. */
 	memset(final, 0, sizeof(final));

 	return passwd;
 }

 #undef MD5_SIZE_OVER_SPEED
 #undef MD5_MAGIC_STR
 #undef MD5_MAGIC_LEN
 #undef __md5_Encode
 #undef __md5_Decode
 #undef F
 #undef G
 #undef H
 #undef I
 #undef ROTATE_LEFT
 #undef FF
 #undef GG
 #undef HH
 #undef II
 #undef S11
 #undef S12
 #undef S13
 #undef S14
 #undef S21
 #undef S22
 #undef S23
 #undef S24
 #undef S31
 #undef S32
 #undef S33
 #undef S34
 #undef S41
 #undef S42
 #undef S43
 #undef S44
	/*
	* MD5C.C - RSA Data Security, Inc., MD5 message-digest algorithm
	*
	* Copyright (C) 1991-2, RSA Data Security, Inc. Created 1991. All
	* rights reserved.
	*
	* License to copy and use this software is granted provided that it
	* is identified as the "RSA Data Security, Inc. MD5 Message-Digest
	* Algorithm" in all material mentioning or referencing this software
	* or this function.
	*
	* License is also granted to make and use derivative works provided
	* that such works are identified as "derived from the RSA Data
	* Security, Inc. MD5 Message-Digest Algorithm" in all material
	* mentioning or referencing the derived work.
	*
	* 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.
	*
	* These notices must be retained in any copies of any part of this
	* documentation and/or software.
	*
	* $FreeBSD: src/lib/libmd/md5c.c,v 1.9.2.1 1999/08/29 14:57:12 peter Exp $
	*
	* This code is the same as the code published by RSA Inc. It has been
	* edited for clarity and style only.
	*
	* ----------------------------------------------------------------------------
	* The md5_crypt() function was taken from freeBSD's libcrypt and contains
	* this license:
	* "THE BEER-WARE LICENSE" (Revision 42):
	* <phk@login.dknet.dk> wrote this file. As long as you retain this notice you
	* can do whatever you want with this stuff. If we meet some day, and you think
	* this stuff is worth it, you can buy me a beer in return. Poul-Henning Kamp
	*
	* $FreeBSD: src/lib/libcrypt/crypt.c,v 1.7.2.1 1999/08/29 14:56:33 peter Exp $
	*
	* ----------------------------------------------------------------------------
	* On April 19th, 2001 md5_crypt() was modified to make it reentrant
	* by Erik Andersen <andersen@uclibc.org>
	*
	*
	* June 28, 2001 Manuel Novoa III
	*
	* "Un-inlined" code using loops and static const tables in order to
	* reduce generated code size (on i386 from approx 4k to approx 2.5k).
	*
	* June 29, 2001 Manuel Novoa III
	*
	* Completely removed static PADDING array.
	*
	* Reintroduced the loop unrolling in MD5_Transform and added the
	* MD5_SIZE_OVER_SPEED option for configurability. Define below as:
	* 0 fully unrolled loops
	* 1 partially unrolled (4 ops per loop)
	* 2 no unrolling -- introduces the need to swap 4 variables (slow)
	* 3 no unrolling and all 4 loops merged into one with switch
	* in each loop (glacial)
	* On i386, sizes are roughly (-Os -fno-builtin):
	* 0: 3k 1: 2.5k 2: 2.2k 3: 2k
	*
	*
	* Since SuSv3 does not require crypt_r, modified again August 7, 2002
	* by Erik Andersen to remove reentrance stuff...
	*/

	/*
	* Valid values are 1 (fastest/largest) to 3 (smallest/slowest).
	*/
	#define MD5_SIZE_OVER_SPEED 3

	/**********************************************************************/

	/* MD5 context. */
	struct MD5Context {
	uint32_t state[4]; /* state (ABCD) */
	uint32_t count[2]; /* number of bits, modulo 2^64 (lsb first) */
	unsigned char buffer[64]; /* input buffer */
	};

	static void __md5_Init(struct MD5Context *);
	static void __md5_Update(struct MD5Context , const unsigned char , unsigned int);
	static void __md5_Pad(struct MD5Context *);
	static void __md5_Final(unsigned char [16], struct MD5Context *);
	static void __md5_Transform(uint32_t [4], const unsigned char [64]);


	#define MD5_MAGIC_STR "$1$"
	#define MD5_MAGIC_LEN (sizeof(MD5_MAGIC_STR) - 1)
	static const unsigned char __md5__magic[] = MD5_MAGIC_STR;


	#ifdef i386
	#define __md5_Encode memcpy
	#define __md5_Decode memcpy
	#else /* i386 */

	/*
	* __md5_Encodes input (uint32_t) into output (unsigned char). Assumes len is
	* a multiple of 4.
	*/
	static void
	__md5_Encode(unsigned char output, uint32_t input, unsigned int len)
	{
	unsigned int i, j;

	for (i = 0, j = 0; j < len; i++, j += 4) {
	output[j] = input[i];
	output[j+1] = (input[i] >> 8);
	output[j+2] = (input[i] >> 16);
	output[j+3] = (input[i] >> 24);
	}
	}

	/*
	* __md5_Decodes input (unsigned char) into output (uint32_t). Assumes len is
	* a multiple of 4.
	*/
	static void
	__md5_Decode(uint32_t output, const unsigned char input, unsigned int len)
	{
	unsigned int i, j;

	for (i = 0, j = 0; j < len; i++, j += 4)
	output[i] = ((uint32_t)input[j]) \| (((uint32_t)input[j+1]) << 8) \|
	(((uint32_t)input[j+2]) << 16) \| (((uint32_t)input[j+3]) << 24);
	}
	#endif /* i386 */

	/* F, G, H and I are basic MD5 functions. */
	#define F(x, y, z) (((x) & (y)) \| (~(x) & (z)))
	#define G(x, y, z) (((x) & (z)) \| ((y) & ~(z)))
	#define H(x, y, z) ((x) ^ (y) ^ (z))
	#define I(x, y, z) ((y) ^ ((x) \| ~(z)))

	/* ROTATE_LEFT rotates x left n bits. */
	#define ROTATE_LEFT(x, n) (((x) << (n)) \| ((x) >> (32-(n))))

	/*
	* FF, GG, HH, and II transformations for rounds 1, 2, 3, and 4.
	* Rotation is separate from addition to prevent recomputation.
	*/
	#define FF(a, b, c, d, x, s, ac) { \
	(a) += F ((b), (c), (d)) + (x) + (uint32_t)(ac); \
	(a) = ROTATE_LEFT((a), (s)); \
	(a) += (b); \
	}
	#define GG(a, b, c, d, x, s, ac) { \
	(a) += G ((b), (c), (d)) + (x) + (uint32_t)(ac); \
	(a) = ROTATE_LEFT((a), (s)); \
	(a) += (b); \
	}
	#define HH(a, b, c, d, x, s, ac) { \
	(a) += H ((b), (c), (d)) + (x) + (uint32_t)(ac); \
	(a) = ROTATE_LEFT((a), (s)); \
	(a) += (b); \
	}
	#define II(a, b, c, d, x, s, ac) { \
	(a) += I ((b), (c), (d)) + (x) + (uint32_t)(ac); \
	(a) = ROTATE_LEFT((a), (s)); \
	(a) += (b); \
	}

	/* MD5 initialization. Begins an MD5 operation, writing a new context. */
	static void __md5_Init(struct MD5Context *context)
	{
	context->count[0] = context->count[1] = 0;

	/* Load magic initialization constants. */
	context->state[0] = 0x67452301;
	context->state[1] = 0xefcdab89;
	context->state[2] = 0x98badcfe;
	context->state[3] = 0x10325476;
	}

	/*
	* MD5 block update operation. Continues an MD5 message-digest
	* operation, processing another message block, and updating the
	* context.
	*/
	static void __md5_Update(struct MD5Context context, const unsigned char input, unsigned int inputLen)
	{
	unsigned int i, idx, partLen;

	/* Compute number of bytes mod 64 */
	idx = (context->count[0] >> 3) & 0x3F;

	/* Update number of bits */
	context->count[0] += (inputLen << 3);
	if (context->count[0] < (inputLen << 3))
	context->count[1]++;
	context->count[1] += (inputLen >> 29);

	partLen = 64 - idx;

	/* Transform as many times as possible. */
	if (inputLen >= partLen) {
	memcpy(&context->buffer[idx], input, partLen);
	__md5_Transform(context->state, context->buffer);

	for (i = partLen; i + 63 < inputLen; i += 64)
	__md5_Transform(context->state, &input[i]);

	idx = 0;
	} else
	i = 0;

	/* Buffer remaining input */
	memcpy(&context->buffer[idx], &input[i], inputLen - i);
	}

	/*
	* MD5 padding. Adds padding followed by original length.
	*/
	static void __md5_Pad(struct MD5Context *context)
	{
	unsigned char bits[8];
	unsigned int idx, padLen;
	unsigned char PADDING[64];

	memset(PADDING, 0, sizeof(PADDING));
	PADDING[0] = 0x80;

	/* Save number of bits */
	__md5_Encode(bits, context->count, 8);

	/* Pad out to 56 mod 64. */
	idx = (context->count[0] >> 3) & 0x3f;
	padLen = (idx < 56) ? (56 - idx) : (120 - idx);
	__md5_Update(context, PADDING, padLen);

	/* Append length (before padding) */
	__md5_Update(context, bits, 8);
	}

	/*
	* MD5 finalization. Ends an MD5 message-digest operation, writing the
	* the message digest and zeroizing the context.
	*/
	static void __md5_Final(unsigned char digest[16], struct MD5Context *context)
	{
	/* Do padding. */
	__md5_Pad(context);

	/* Store state in digest */
	__md5_Encode(digest, context->state, 16);

	/* Zeroize sensitive information. */
	memset(context, 0, sizeof(*context));
	}

	/* MD5 basic transformation. Transforms state based on block. */
	static void __md5_Transform(uint32_t state[4], const unsigned char block[64])
	{
	uint32_t a, b, c, d, x[16];
	#if MD5_SIZE_OVER_SPEED > 1
	uint32_t temp;
	const unsigned char *ps;

	static const unsigned char S[] = {
	7, 12, 17, 22,
	5, 9, 14, 20,
	4, 11, 16, 23,
	6, 10, 15, 21
	};
	#endif /* MD5_SIZE_OVER_SPEED > 1 */

	#if MD5_SIZE_OVER_SPEED > 0
	const uint32_t *pc;
	const unsigned char *pp;
	int i;

	static const uint32_t C[] = {
	/* round 1 */
	0xd76aa478, 0xe8c7b756, 0x242070db, 0xc1bdceee,
	0xf57c0faf, 0x4787c62a, 0xa8304613, 0xfd469501,
	0x698098d8, 0x8b44f7af, 0xffff5bb1, 0x895cd7be,
	0x6b901122, 0xfd987193, 0xa679438e, 0x49b40821,
	/* round 2 */
	0xf61e2562, 0xc040b340, 0x265e5a51, 0xe9b6c7aa,
	0xd62f105d, 0x2441453, 0xd8a1e681, 0xe7d3fbc8,
	0x21e1cde6, 0xc33707d6, 0xf4d50d87, 0x455a14ed,
	0xa9e3e905, 0xfcefa3f8, 0x676f02d9, 0x8d2a4c8a,
	/* round 3 */
	0xfffa3942, 0x8771f681, 0x6d9d6122, 0xfde5380c,
	0xa4beea44, 0x4bdecfa9, 0xf6bb4b60, 0xbebfbc70,
	0x289b7ec6, 0xeaa127fa, 0xd4ef3085, 0x4881d05,
	0xd9d4d039, 0xe6db99e5, 0x1fa27cf8, 0xc4ac5665,
	/* round 4 */
	0xf4292244, 0x432aff97, 0xab9423a7, 0xfc93a039,
	0x655b59c3, 0x8f0ccc92, 0xffeff47d, 0x85845dd1,
	0x6fa87e4f, 0xfe2ce6e0, 0xa3014314, 0x4e0811a1,
	0xf7537e82, 0xbd3af235, 0x2ad7d2bb, 0xeb86d391
	};

	static const unsigned char P[] = {
	0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, /* 1 */
	1, 6, 11, 0, 5, 10, 15, 4, 9, 14, 3, 8, 13, 2, 7, 12, /* 2 */
	5, 8, 11, 14, 1, 4, 7, 10, 13, 0, 3, 6, 9, 12, 15, 2, /* 3 */
	0, 7, 14, 5, 12, 3, 10, 1, 8, 15, 6, 13, 4, 11, 2, 9 /* 4 */
	};

	#endif /* MD5_SIZE_OVER_SPEED > 0 */

	__md5_Decode(x, block, 64);

	a = state[0]; b = state[1]; c = state[2]; d = state[3];

	#if MD5_SIZE_OVER_SPEED > 2
	pc = C; pp = P; ps = S - 4;

	for (i = 0; i < 64; i++) {
	if ((i & 0x0f) == 0) ps += 4;
	temp = a;
	switch (i>>4) {
	case 0:
	temp += F(b, c, d);
	break;
	case 1:
	temp += G(b, c, d);
	break;
	case 2:
	temp += H(b, c, d);
	break;
	case 3:
	temp += I(b, c, d);
	break;
	}
	temp += x[pp++] + pc++;
	temp = ROTATE_LEFT(temp, ps[i & 3]);
	temp += b;
	a = d; d = c; c = b; b = temp;
	}
	#elif MD5_SIZE_OVER_SPEED > 1
	pc = C; pp = P; ps = S;

	/* Round 1 */
	for (i = 0; i < 16; i++) {
	FF(a, b, c, d, x[pp], ps[i & 0x3], pc); pp++; pc++;
	temp = d; d = c; c = b; b = a; a = temp;
	}

	/* Round 2 */
	ps += 4;
	for (; i < 32; i++) {
	GG(a, b, c, d, x[pp], ps[i & 0x3], pc); pp++; pc++;
	temp = d; d = c; c = b; b = a; a = temp;
	}
	/* Round 3 */
	ps += 4;
	for (; i < 48; i++) {
	HH(a, b, c, d, x[pp], ps[i & 0x3], pc); pp++; pc++;
	temp = d; d = c; c = b; b = a; a = temp;
	}

	/* Round 4 */
	ps += 4;
	for (; i < 64; i++) {
	II(a, b, c, d, x[pp], ps[i & 0x3], pc); pp++; pc++;
	temp = d; d = c; c = b; b = a; a = temp;
	}
	#elif MD5_SIZE_OVER_SPEED > 0
	pc = C; pp = P;

	/* Round 1 */
	for (i = 0; i < 4; i++) {
	FF(a, b, c, d, x[pp], 7, pc); pp++; pc++;
	FF(d, a, b, c, x[pp], 12, pc); pp++; pc++;
	FF(c, d, a, b, x[pp], 17, pc); pp++; pc++;
	FF(b, c, d, a, x[pp], 22, pc); pp++; pc++;
	}

	/* Round 2 */
	for (i = 0; i < 4; i++) {
	GG(a, b, c, d, x[pp], 5, pc); pp++; pc++;
	GG(d, a, b, c, x[pp], 9, pc); pp++; pc++;
	GG(c, d, a, b, x[pp], 14, pc); pp++; pc++;
	GG(b, c, d, a, x[pp], 20, pc); pp++; pc++;
	}
	/* Round 3 */
	for (i = 0; i < 4; i++) {
	HH(a, b, c, d, x[pp], 4, pc); pp++; pc++;
	HH(d, a, b, c, x[pp], 11, pc); pp++; pc++;
	HH(c, d, a, b, x[pp], 16, pc); pp++; pc++;
	HH(b, c, d, a, x[pp], 23, pc); pp++; pc++;
	}

	/* Round 4 */
	for (i = 0; i < 4; i++) {
	II(a, b, c, d, x[pp], 6, pc); pp++; pc++;
	II(d, a, b, c, x[pp], 10, pc); pp++; pc++;
	II(c, d, a, b, x[pp], 15, pc); pp++; pc++;
	II(b, c, d, a, x[pp], 21, pc); pp++; pc++;
	}
	#else
	/* Round 1 */
	#define S11 7
	#define S12 12
	#define S13 17
	#define S14 22
	FF(a, b, c, d, x[ 0], S11, 0xd76aa478); /* 1 */
	FF(d, a, b, c, x[ 1], S12, 0xe8c7b756); /* 2 */
	FF(c, d, a, b, x[ 2], S13, 0x242070db); /* 3 */
	FF(b, c, d, a, x[ 3], S14, 0xc1bdceee); /* 4 */
	FF(a, b, c, d, x[ 4], S11, 0xf57c0faf); /* 5 */
	FF(d, a, b, c, x[ 5], S12, 0x4787c62a); /* 6 */
	FF(c, d, a, b, x[ 6], S13, 0xa8304613); /* 7 */
	FF(b, c, d, a, x[ 7], S14, 0xfd469501); /* 8 */
	FF(a, b, c, d, x[ 8], S11, 0x698098d8); /* 9 */
	FF(d, a, b, c, x[ 9], S12, 0x8b44f7af); /* 10 */
	FF(c, d, a, b, x[10], S13, 0xffff5bb1); /* 11 */
	FF(b, c, d, a, x[11], S14, 0x895cd7be); /* 12 */
	FF(a, b, c, d, x[12], S11, 0x6b901122); /* 13 */
	FF(d, a, b, c, x[13], S12, 0xfd987193); /* 14 */
	FF(c, d, a, b, x[14], S13, 0xa679438e); /* 15 */
	FF(b, c, d, a, x[15], S14, 0x49b40821); /* 16 */

	/* Round 2 */
	#define S21 5
	#define S22 9
	#define S23 14
	#define S24 20
	GG(a, b, c, d, x[ 1], S21, 0xf61e2562); /* 17 */
	GG(d, a, b, c, x[ 6], S22, 0xc040b340); /* 18 */
	GG(c, d, a, b, x[11], S23, 0x265e5a51); /* 19 */
	GG(b, c, d, a, x[ 0], S24, 0xe9b6c7aa); /* 20 */
	GG(a, b, c, d, x[ 5], S21, 0xd62f105d); /* 21 */
	GG(d, a, b, c, x[10], S22, 0x2441453); /* 22 */
	GG(c, d, a, b, x[15], S23, 0xd8a1e681); /* 23 */
	GG(b, c, d, a, x[ 4], S24, 0xe7d3fbc8); /* 24 */
	GG(a, b, c, d, x[ 9], S21, 0x21e1cde6); /* 25 */
	GG(d, a, b, c, x[14], S22, 0xc33707d6); /* 26 */
	GG(c, d, a, b, x[ 3], S23, 0xf4d50d87); /* 27 */
	GG(b, c, d, a, x[ 8], S24, 0x455a14ed); /* 28 */
	GG(a, b, c, d, x[13], S21, 0xa9e3e905); /* 29 */
	GG(d, a, b, c, x[ 2], S22, 0xfcefa3f8); /* 30 */
	GG(c, d, a, b, x[ 7], S23, 0x676f02d9); /* 31 */
	GG(b, c, d, a, x[12], S24, 0x8d2a4c8a); /* 32 */

	/* Round 3 */
	#define S31 4
	#define S32 11
	#define S33 16
	#define S34 23
	HH(a, b, c, d, x[ 5], S31, 0xfffa3942); /* 33 */
	HH(d, a, b, c, x[ 8], S32, 0x8771f681); /* 34 */
	HH(c, d, a, b, x[11], S33, 0x6d9d6122); /* 35 */
	HH(b, c, d, a, x[14], S34, 0xfde5380c); /* 36 */
	HH(a, b, c, d, x[ 1], S31, 0xa4beea44); /* 37 */
	HH(d, a, b, c, x[ 4], S32, 0x4bdecfa9); /* 38 */
	HH(c, d, a, b, x[ 7], S33, 0xf6bb4b60); /* 39 */
	HH(b, c, d, a, x[10], S34, 0xbebfbc70); /* 40 */
	HH(a, b, c, d, x[13], S31, 0x289b7ec6); /* 41 */
	HH(d, a, b, c, x[ 0], S32, 0xeaa127fa); /* 42 */
	HH(c, d, a, b, x[ 3], S33, 0xd4ef3085); /* 43 */
	HH(b, c, d, a, x[ 6], S34, 0x4881d05); /* 44 */
	HH(a, b, c, d, x[ 9], S31, 0xd9d4d039); /* 45 */
	HH(d, a, b, c, x[12], S32, 0xe6db99e5); /* 46 */
	HH(c, d, a, b, x[15], S33, 0x1fa27cf8); /* 47 */
	HH(b, c, d, a, x[ 2], S34, 0xc4ac5665); /* 48 */

	/* Round 4 */
	#define S41 6
	#define S42 10
	#define S43 15
	#define S44 21
	II(a, b, c, d, x[ 0], S41, 0xf4292244); /* 49 */
	II(d, a, b, c, x[ 7], S42, 0x432aff97); /* 50 */
	II(c, d, a, b, x[14], S43, 0xab9423a7); /* 51 */
	II(b, c, d, a, x[ 5], S44, 0xfc93a039); /* 52 */
	II(a, b, c, d, x[12], S41, 0x655b59c3); /* 53 */
	II(d, a, b, c, x[ 3], S42, 0x8f0ccc92); /* 54 */
	II(c, d, a, b, x[10], S43, 0xffeff47d); /* 55 */
	II(b, c, d, a, x[ 1], S44, 0x85845dd1); /* 56 */
	II(a, b, c, d, x[ 8], S41, 0x6fa87e4f); /* 57 */
	II(d, a, b, c, x[15], S42, 0xfe2ce6e0); /* 58 */
	II(c, d, a, b, x[ 6], S43, 0xa3014314); /* 59 */
	II(b, c, d, a, x[13], S44, 0x4e0811a1); /* 60 */
	II(a, b, c, d, x[ 4], S41, 0xf7537e82); /* 61 */
	II(d, a, b, c, x[11], S42, 0xbd3af235); /* 62 */
	II(c, d, a, b, x[ 2], S43, 0x2ad7d2bb); /* 63 */
	II(b, c, d, a, x[ 9], S44, 0xeb86d391); /* 64 */
	#endif

	state[0] += a;
	state[1] += b;
	state[2] += c;
	state[3] += d;

	/* Zeroize sensitive information. */
	memset(x, 0, sizeof(x));
	}


	static char*
	__md5_to64(char *s, unsigned v, int n)
	{
	while (--n >= 0) {
	*s++ = ascii64[v & 0x3f];
	v >>= 6;
	}
	return s;
	}

	/*
	* UNIX password
	*
	* Use MD5 for what it is best at...
	*/
	#define MD5_OUT_BUFSIZE 36
	static char *
	NOINLINE
	md5_crypt(char passwd[MD5_OUT_BUFSIZE], const unsigned char pw, const unsigned char salt)
	{
	const unsigned char sp, ep;
	char *p;
	unsigned char final[17]; /* final[16] exists only to aid in looping */
	int sl, pl, i, pw_len;
	struct MD5Context ctx, ctx1;

	/* Refine the Salt first */
	sp = salt;

	// always true for bbox
	// /* If it starts with the magic string, then skip that */
	// if (!strncmp(sp, __md5__magic, MD5_MAGIC_LEN))
	sp += MD5_MAGIC_LEN;

	/* It stops at the first '$', max 8 chars */
	for (ep = sp; ep && ep != '$' && ep < (sp+8); ep++)
	continue;

	/* get the length of the true salt */
	sl = ep - sp;

	__md5_Init(&ctx);

	/* The password first, since that is what is most unknown */
	pw_len = strlen((char*)pw);
	__md5_Update(&ctx, pw, pw_len);

	/* Then our magic string */
	__md5_Update(&ctx, __md5__magic, MD5_MAGIC_LEN);

	/* Then the raw salt */
	__md5_Update(&ctx, sp, sl);

	/* Then just as many characters of the MD5(pw, salt, pw) */
	__md5_Init(&ctx1);
	__md5_Update(&ctx1, pw, pw_len);
	__md5_Update(&ctx1, sp, sl);
	__md5_Update(&ctx1, pw, pw_len);
	__md5_Final(final, &ctx1);
	for (pl = pw_len; pl > 0; pl -= 16)
	__md5_Update(&ctx, final, pl > 16 ? 16 : pl);

	/* Don't leave anything around in vm they could use. */
	//TODO: the above comment seems to be wrong. final is used later.
	memset(final, 0, sizeof(final));

	/* Then something really weird... */
	for (i = pw_len; i; i >>= 1) {
	__md5_Update(&ctx, ((i & 1) ? final : (const unsigned char *) pw), 1);
	}

	/* Now make the output string */
	passwd[0] = '$';
	passwd[1] = '1';
	passwd[2] = '$';
	strncpy(passwd + 3, (char*)sp, sl);
	passwd[sl + 3] = '$';

	__md5_Final(final, &ctx);

	/*
	* and now, just to make sure things don't run too fast
	* On a 60 Mhz Pentium this takes 34 msec, so you would
	* need 30 seconds to build a 1000 entry dictionary...
	*/
	for (i = 0; i < 1000; i++) {
	__md5_Init(&ctx1);
	if (i & 1)
	__md5_Update(&ctx1, pw, pw_len);
	else
	__md5_Update(&ctx1, final, 16);

	if (i % 3)
	__md5_Update(&ctx1, sp, sl);

	if (i % 7)
	__md5_Update(&ctx1, pw, pw_len);

	if (i & 1)
	__md5_Update(&ctx1, final, 16);
	else
	__md5_Update(&ctx1, pw, pw_len);
	__md5_Final(final, &ctx1);
	}

	p = passwd + sl + 4; /* 12 bytes max (sl is up to 8 bytes) */

	/* Add 54+2 = 22 bytes of hash, + NUL byte. /
	final[16] = final[5];
	for (i = 0; i < 5; i++) {
	unsigned l = (final[i] << 16) \| (final[i+6] << 8) \| final[i+12];
	p = __md5_to64(p, l, 4);
	}
	p = __md5_to64(p, final[11], 2);
	*p = '\0';

	/* Don't leave anything around in vm they could use. */
	memset(final, 0, sizeof(final));

	return passwd;
	}

	#undef MD5_SIZE_OVER_SPEED
	#undef MD5_MAGIC_STR
	#undef MD5_MAGIC_LEN
	#undef __md5_Encode
	#undef __md5_Decode
	#undef F
	#undef G
	#undef H
	#undef I
	#undef ROTATE_LEFT
	#undef FF
	#undef GG
	#undef HH
	#undef II
	#undef S11
	#undef S12
	#undef S13
	#undef S14
	#undef S21
	#undef S22
	#undef S23
	#undef S24
	#undef S31
	#undef S32
	#undef S33
	#undef S34
	#undef S41
	#undef S42
	#undef S43
	#undef S44