lib/apr_md5.c - apr - Git at Google

 /*
  * This is work is derived from material Copyright RSA Data Security, Inc.
  *
  * The RSA copyright statement and Licence for that original material is
  * included below. This is followed by the Apache copyright statement and
  * licence for the modifications made to that material.
  */

 /* 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.
  */

 /* ====================================================================
  * Copyright (c) 1996-1999 The Apache Group.  All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  *
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in
  *    the documentation and/or other materials provided with the
  *    distribution.
  *
  * 3. All advertising materials mentioning features or use of this
  *    software must display the following acknowledgment:
  *    "This product includes software developed by the Apache Group
  *    for use in the Apache HTTP server project (http://www.apache.org/)."
  *
  * 4. The names "Apache Server" and "Apache Group" must not be used to
  *    endorse or promote products derived from this software without
  *    prior written permission. For written permission, please contact
  *    apache@apache.org.
  *
  * 5. Products derived from this software may not be called "Apache"
  *    nor may "Apache" appear in their names without prior written
  *    permission of the Apache Group.
  *
  * 6. Redistributions of any form whatsoever must retain the following
  *    acknowledgment:
  *    "This product includes software developed by the Apache Group
  *    for use in the Apache HTTP server project (http://www.apache.org/)."
  *
  * THIS SOFTWARE IS PROVIDED BY THE APACHE GROUP ``AS IS'' AND ANY
  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE APACHE GROUP OR
  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
  * OF THE POSSIBILITY OF SUCH DAMAGE.
  * ====================================================================
  *
  * This software consists of voluntary contributions made by many
  * individuals on behalf of the Apache Group and was originally based
  * on public domain software written at the National Center for
  * Supercomputing Applications, University of Illinois, Urbana-Champaign.
  * For more information on the Apache Group and the Apache HTTP server
  * project, please see <http://www.apache.org/>.
  *
  */

 /*
  * The apr_MD5Encode() routine uses much code obtained from the FreeBSD 3.0
  * MD5 crypt() function, which is licenced as follows:
  * ----------------------------------------------------------------------------
  * "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
  * ----------------------------------------------------------------------------
  */
 #ifndef WIN32
 #include "apr_config.h"
 #endif
 #include "apr_md5.h"
 #include "apr_lib.h"

 #ifdef HAVE_CRYPT_H
 #include <crypt.h>
 #endif

 /* Constants for MD5Transform routine.
  */

 #define S11 7
 #define S12 12
 #define S13 17
 #define S14 22
 #define S21 5
 #define S22 9
 #define S23 14
 #define S24 20
 #define S31 4
 #define S32 11
 #define S33 16
 #define S34 23
 #define S41 6
 #define S42 10
 #define S43 15
 #define S44 21

 static void MD5Transform(UINT4 state[4], const unsigned char block[64]);
 static void Encode(unsigned char *output, const UINT4 *input,
 		   unsigned int len);
 static void Decode(UINT4 *output, const unsigned char *input,
 		   unsigned int len);

 static unsigned char PADDING[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
 };

 /* 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) + (UINT4)(ac); \
  (a) = ROTATE_LEFT ((a), (s)); \
  (a) += (b); \
   }
 #define GG(a, b, c, d, x, s, ac) { \
  (a) += G ((b), (c), (d)) + (x) + (UINT4)(ac); \
  (a) = ROTATE_LEFT ((a), (s)); \
  (a) += (b); \
   }
 #define HH(a, b, c, d, x, s, ac) { \
  (a) += H ((b), (c), (d)) + (x) + (UINT4)(ac); \
  (a) = ROTATE_LEFT ((a), (s)); \
  (a) += (b); \
   }
 #define II(a, b, c, d, x, s, ac) { \
  (a) += I ((b), (c), (d)) + (x) + (UINT4)(ac); \
  (a) = ROTATE_LEFT ((a), (s)); \
  (a) += (b); \
   }

 /* MD5 initialization. Begins an MD5 operation, writing a new context.
  */
 API_EXPORT(void) apr_MD5Init(APR_MD5_CTX * 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.
  */
 API_EXPORT(void) apr_MD5Update(APR_MD5_CTX * context, const unsigned char *input,
 			   unsigned int inputLen)
 {
     unsigned int i, idx, partLen;

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

     /* Update number of bits */
     if ((context->count[0] += ((UINT4) inputLen << 3)) < ((UINT4) inputLen << 3))
 	context->count[1]++;
     context->count[1] += (UINT4) inputLen >> 29;

     partLen = 64 - idx;

     /* Transform as many times as possible. */
 #ifndef CHARSET_EBCDIC
     if (inputLen >= partLen) {
 	memcpy(&context->buffer[idx], input, partLen);
 	MD5Transform(context->state, context->buffer);

 	for (i = partLen; i + 63 < inputLen; i += 64)
 	    MD5Transform(context->state, &input[i]);

 	idx = 0;
     }
     else
 	i = 0;

     /* Buffer remaining input */
     memcpy(&context->buffer[idx], &input[i], inputLen - i);
 #else /*CHARSET_EBCDIC*/
     if (inputLen >= partLen) {
 	ebcdic2ascii_strictly(&context->buffer[idx], input, partLen);
 	MD5Transform(context->state, context->buffer);

 	for (i = partLen; i + 63 < inputLen; i += 64) {
 	    unsigned char inp_tmp[64];
 	    ebcdic2ascii_strictly(inp_tmp, &input[i], 64);
 	    MD5Transform(context->state, inp_tmp);
 	}

 	idx = 0;
     }
     else
 	i = 0;

     /* Buffer remaining input */
     ebcdic2ascii_strictly(&context->buffer[idx], &input[i], inputLen - i);
 #endif /*CHARSET_EBCDIC*/
 }

 /* MD5 finalization. Ends an MD5 message-digest operation, writing the
    the message digest and zeroizing the context.
  */
 API_EXPORT(void) apr_MD5Final(unsigned char digest[16], APR_MD5_CTX * context)
 {
     unsigned char bits[8];
     unsigned int idx, padLen;


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

 #ifdef CHARSET_EBCDIC
     /* XXX: @@@: In order to make this no more complex than necessary,
      * this kludge converts the bits[] array using the ascii-to-ebcdic
      * table, because the following apr_MD5Update() re-translates
      * its input (ebcdic-to-ascii).
      * Otherwise, we would have to pass a "conversion" flag to apr_MD5Update()
      */
     ascii2ebcdic(bits,bits,8);

     /* Since everything is converted to ascii within apr_MD5Update(),
      * the initial 0x80 (PADDING[0]) must be stored as 0x20
      */
     PADDING[0] = os_toebcdic[0x80];
 #endif /*CHARSET_EBCDIC*/

     /* Pad out to 56 mod 64. */
     idx = (unsigned int) ((context->count[0] >> 3) & 0x3f);
     padLen = (idx < 56) ? (56 - idx) : (120 - idx);
     apr_MD5Update(context, PADDING, padLen);

     /* Append length (before padding) */
     apr_MD5Update(context, bits, 8);

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

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

 /* MD5 basic transformation. Transforms state based on block. */
 static void MD5Transform(UINT4 state[4], const unsigned char block[64])
 {
     UINT4 a = state[0], b = state[1], c = state[2], d = state[3], x[16];

     Decode(x, block, 64);

     /* Round 1 */
     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 */
     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 */
     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 */
     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 */

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

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

 /* Encodes input (UINT4) into output (unsigned char). Assumes len is
    a multiple of 4.
  */
 static void Encode(unsigned char *output, const UINT4 *input, unsigned int len)
 {
     unsigned int i, j;
     UINT4 k;

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

 /* Decodes input (unsigned char) into output (UINT4). Assumes len is
  * a multiple of 4.
  */
 static void Decode(UINT4 *output, const unsigned char *input, unsigned int len)
 {
     unsigned int i, j;

     for (i = 0, j = 0; j < len; i++, j += 4)
 	output[i] = ((UINT4) input[j]) | (((UINT4) input[j + 1]) << 8) |
 	    (((UINT4) input[j + 2]) << 16) | (((UINT4) input[j + 3]) << 24);
 }

 /*
  * Define the Magic String prefix that identifies a password as being
  * hashed using our algorithm.
  */
 static const char *apr1_id = "$apr1$";

 /*
  * The following MD5 password encryption code was largely borrowed from
  * the FreeBSD 3.0 /usr/src/lib/libcrypt/crypt.c file, which is
  * licenced as stated at the top of this file.
  */

 static void to64(char *s, unsigned long v, int n)
 {
     static unsigned char itoa64[] =         /* 0 ... 63 => ASCII - 64 */
 	"./0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";

     while (--n >= 0) {
 	*s++ = itoa64[v&0x3f];
 	v >>= 6;
     }
 }

 API_EXPORT(void) apr_MD5Encode(const char *pw, const char *salt,
 			      char *result, size_t nbytes)
 {
     /*
      * Minimum size is 8 bytes for salt, plus 1 for the trailing NUL,
      * plus 4 for the '$' separators, plus the password hash itself.
      * Let's leave a goodly amount of leeway.
      */

     char passwd[120], *p;
     const char *sp, *ep;
     unsigned char final[16];
     int sl, pl, i;
     APR_MD5_CTX ctx, ctx1;
     unsigned long l;

     /*
      * Refine the salt first.  It's possible we were given an already-hashed
      * string as the salt argument, so extract the actual salt value from it
      * if so.  Otherwise just use the string up to the first '$' as the salt.
      */
     sp = salt;

     /*
      * If it starts with the magic string, then skip that.
      */
     if (!strncmp(sp, apr1_id, strlen(apr1_id))) {
 	sp += strlen(apr1_id);
     }

     /*
      * It stops at the first '$' or 8 chars, whichever comes first
      */
     for (ep = sp; (*ep != '\0') && (*ep != '$') && (ep < (sp + 8)); ep++) {
 	continue;
     }

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

     /*
      * 'Time to make the doughnuts..'
      */
     apr_MD5Init(&ctx);

     /*
      * The password first, since that is what is most unknown
      */
     apr_MD5Update(&ctx, pw, strlen(pw));

     /*
      * Then our magic string
      */
     apr_MD5Update(&ctx, apr1_id, strlen(apr1_id));

     /*
      * Then the raw salt
      */
     apr_MD5Update(&ctx, sp, sl);

     /*
      * Then just as many characters of the MD5(pw, salt, pw)
      */
     apr_MD5Init(&ctx1);
     apr_MD5Update(&ctx1, pw, strlen(pw));
     apr_MD5Update(&ctx1, sp, sl);
     apr_MD5Update(&ctx1, pw, strlen(pw));
     apr_MD5Final(final, &ctx1);
     for(pl = strlen(pw); pl > 0; pl -= 16) {
 	apr_MD5Update(&ctx, final, (pl > 16) ? 16 : pl);
     }

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

     /*
      * Then something really weird...
      */
     for (i = strlen(pw); i != 0; i >>= 1) {
 	if (i & 1) {
 	    apr_MD5Update(&ctx, final, 1);
 	}
 	else {
 	    apr_MD5Update(&ctx, pw, 1);
 	}
     }

     /*
      * Now make the output string.  We know our limitations, so we
      * can use the string routines without bounds checking.
      */
     strcpy(passwd, apr1_id);
     strncat(passwd, sp, sl);
     strcat(passwd, "$");

     apr_MD5Final(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++) {
 	apr_MD5Init(&ctx1);
 	if (i & 1) {
 	    apr_MD5Update(&ctx1, pw, strlen(pw));
 	}
 	else {
 	    apr_MD5Update(&ctx1, final, 16);
 	}
 	if (i % 3) {
 	    apr_MD5Update(&ctx1, sp, sl);
 	}

 	if (i % 7) {
 	    apr_MD5Update(&ctx1, pw, strlen(pw));
 	}

 	if (i & 1) {
 	    apr_MD5Update(&ctx1, final, 16);
 	}
 	else {
 	    apr_MD5Update(&ctx1, pw, strlen(pw));
 	}
 	apr_MD5Final(final,&ctx1);
     }

     p = passwd + strlen(passwd);

     l = (final[ 0]<<16) | (final[ 6]<<8) | final[12]; to64(p, l, 4); p += 4;
     l = (final[ 1]<<16) | (final[ 7]<<8) | final[13]; to64(p, l, 4); p += 4;
     l = (final[ 2]<<16) | (final[ 8]<<8) | final[14]; to64(p, l, 4); p += 4;
     l = (final[ 3]<<16) | (final[ 9]<<8) | final[15]; to64(p, l, 4); p += 4;
     l = (final[ 4]<<16) | (final[10]<<8) | final[ 5]; to64(p, l, 4); p += 4;
     l =                    final[11]                ; to64(p, l, 2); p += 2;
     *p = '\0';

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

     apr_cpystrn(result, passwd, nbytes - 1);
 }

 /*
  * Validate a plaintext password against a smashed one.  Use either
  * crypt() (if available) or apr_MD5Encode(), depending upon the format
  * of the smashed input password.  Return NULL if they match, or
  * an explanatory text string if they don't.
  */

 API_EXPORT(char *) apr_validate_password(const char *passwd, const char *hash)
 {
     char sample[120];
 #ifndef WIN32
     char *crypt_pw;
 #endif
     if (!strncmp(hash, apr1_id, strlen(apr1_id))) {
 	/*
 	 * The hash was created using our custom algorithm.
 	 */
 	apr_MD5Encode(passwd, hash, sample, sizeof(sample));
     }
     else {
 	/*
 	 * It's not our algorithm, so feed it to crypt() if possible.
 	 */
 #ifdef WIN32
 	apr_cpystrn(sample, passwd, sizeof(sample) - 1);
 #else
 	crypt_pw = crypt(passwd, hash);
 	apr_cpystrn(sample, crypt_pw, sizeof(sample) - 1);
 #endif
     }
     return (strcmp(sample, hash) == 0) ? NULL : "password mismatch";
 }
	/*
	* This is work is derived from material Copyright RSA Data Security, Inc.
	*
	* The RSA copyright statement and Licence for that original material is
	* included below. This is followed by the Apache copyright statement and
	* licence for the modifications made to that material.
	*/

	/* 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.
	*/

	/* ====================================================================
	* Copyright (c) 1996-1999 The Apache Group. All rights reserved.
	*
	* Redistribution and use in source and binary forms, with or without
	* modification, are permitted provided that the following conditions
	* are met:
	*
	* 1. Redistributions of source code must retain the above copyright
	* notice, this list of conditions and the following disclaimer.
	*
	* 2. Redistributions in binary form must reproduce the above copyright
	* notice, this list of conditions and the following disclaimer in
	* the documentation and/or other materials provided with the
	* distribution.
	*
	* 3. All advertising materials mentioning features or use of this
	* software must display the following acknowledgment:
	* "This product includes software developed by the Apache Group
	* for use in the Apache HTTP server project (http://www.apache.org/)."
	*
	* 4. The names "Apache Server" and "Apache Group" must not be used to
	* endorse or promote products derived from this software without
	* prior written permission. For written permission, please contact
	* apache@apache.org.
	*
	* 5. Products derived from this software may not be called "Apache"
	* nor may "Apache" appear in their names without prior written
	* permission of the Apache Group.
	*
	* 6. Redistributions of any form whatsoever must retain the following
	* acknowledgment:
	* "This product includes software developed by the Apache Group
	* for use in the Apache HTTP server project (http://www.apache.org/)."
	*
	* THIS SOFTWARE IS PROVIDED BY THE APACHE GROUP ``AS IS'' AND ANY
	* EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
	* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE APACHE GROUP OR
	* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
	* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
	* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
	* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
	* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
	* OF THE POSSIBILITY OF SUCH DAMAGE.
	* ====================================================================
	*
	* This software consists of voluntary contributions made by many
	* individuals on behalf of the Apache Group and was originally based
	* on public domain software written at the National Center for
	* Supercomputing Applications, University of Illinois, Urbana-Champaign.
	* For more information on the Apache Group and the Apache HTTP server
	* project, please see <http://www.apache.org/>.
	*
	*/

	/*
	* The apr_MD5Encode() routine uses much code obtained from the FreeBSD 3.0
	* MD5 crypt() function, which is licenced as follows:
	* ----------------------------------------------------------------------------
	* "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
	* ----------------------------------------------------------------------------
	*/
	#ifndef WIN32
	#include "apr_config.h"
	#endif
	#include "apr_md5.h"
	#include "apr_lib.h"

	#ifdef HAVE_CRYPT_H
	#include <crypt.h>
	#endif

	/* Constants for MD5Transform routine.
	*/

	#define S11 7
	#define S12 12
	#define S13 17
	#define S14 22
	#define S21 5
	#define S22 9
	#define S23 14
	#define S24 20
	#define S31 4
	#define S32 11
	#define S33 16
	#define S34 23
	#define S41 6
	#define S42 10
	#define S43 15
	#define S44 21

	static void MD5Transform(UINT4 state[4], const unsigned char block[64]);
	static void Encode(unsigned char output, const UINT4 input,
	unsigned int len);
	static void Decode(UINT4 output, const unsigned char input,
	unsigned int len);

	static unsigned char PADDING[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
	};

	/* 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) + (UINT4)(ac); \
	(a) = ROTATE_LEFT ((a), (s)); \
	(a) += (b); \
	}
	#define GG(a, b, c, d, x, s, ac) { \
	(a) += G ((b), (c), (d)) + (x) + (UINT4)(ac); \
	(a) = ROTATE_LEFT ((a), (s)); \
	(a) += (b); \
	}
	#define HH(a, b, c, d, x, s, ac) { \
	(a) += H ((b), (c), (d)) + (x) + (UINT4)(ac); \
	(a) = ROTATE_LEFT ((a), (s)); \
	(a) += (b); \
	}
	#define II(a, b, c, d, x, s, ac) { \
	(a) += I ((b), (c), (d)) + (x) + (UINT4)(ac); \
	(a) = ROTATE_LEFT ((a), (s)); \
	(a) += (b); \
	}

	/* MD5 initialization. Begins an MD5 operation, writing a new context.
	*/
	API_EXPORT(void) apr_MD5Init(APR_MD5_CTX * 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.
	*/
	API_EXPORT(void) apr_MD5Update(APR_MD5_CTX * context, const unsigned char *input,
	unsigned int inputLen)
	{
	unsigned int i, idx, partLen;

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

	/* Update number of bits */
	if ((context->count[0] += ((UINT4) inputLen << 3)) < ((UINT4) inputLen << 3))
	context->count[1]++;
	context->count[1] += (UINT4) inputLen >> 29;

	partLen = 64 - idx;

	/* Transform as many times as possible. */
	#ifndef CHARSET_EBCDIC
	if (inputLen >= partLen) {
	memcpy(&context->buffer[idx], input, partLen);
	MD5Transform(context->state, context->buffer);

	for (i = partLen; i + 63 < inputLen; i += 64)
	MD5Transform(context->state, &input[i]);

	idx = 0;
	}
	else
	i = 0;

	/* Buffer remaining input */
	memcpy(&context->buffer[idx], &input[i], inputLen - i);
	#else /CHARSET_EBCDIC/
	if (inputLen >= partLen) {
	ebcdic2ascii_strictly(&context->buffer[idx], input, partLen);
	MD5Transform(context->state, context->buffer);

	for (i = partLen; i + 63 < inputLen; i += 64) {
	unsigned char inp_tmp[64];
	ebcdic2ascii_strictly(inp_tmp, &input[i], 64);
	MD5Transform(context->state, inp_tmp);
	}

	idx = 0;
	}
	else
	i = 0;

	/* Buffer remaining input */
	ebcdic2ascii_strictly(&context->buffer[idx], &input[i], inputLen - i);
	#endif /CHARSET_EBCDIC/
	}

	/* MD5 finalization. Ends an MD5 message-digest operation, writing the
	the message digest and zeroizing the context.
	*/
	API_EXPORT(void) apr_MD5Final(unsigned char digest[16], APR_MD5_CTX * context)
	{
	unsigned char bits[8];
	unsigned int idx, padLen;


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

	#ifdef CHARSET_EBCDIC
	/* XXX: @@@: In order to make this no more complex than necessary,
	* this kludge converts the bits[] array using the ascii-to-ebcdic
	* table, because the following apr_MD5Update() re-translates
	* its input (ebcdic-to-ascii).
	* Otherwise, we would have to pass a "conversion" flag to apr_MD5Update()
	*/
	ascii2ebcdic(bits,bits,8);

	/* Since everything is converted to ascii within apr_MD5Update(),
	* the initial 0x80 (PADDING[0]) must be stored as 0x20
	*/
	PADDING[0] = os_toebcdic[0x80];
	#endif /CHARSET_EBCDIC/

	/* Pad out to 56 mod 64. */
	idx = (unsigned int) ((context->count[0] >> 3) & 0x3f);
	padLen = (idx < 56) ? (56 - idx) : (120 - idx);
	apr_MD5Update(context, PADDING, padLen);

	/* Append length (before padding) */
	apr_MD5Update(context, bits, 8);

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

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

	/* MD5 basic transformation. Transforms state based on block. */
	static void MD5Transform(UINT4 state[4], const unsigned char block[64])
	{
	UINT4 a = state[0], b = state[1], c = state[2], d = state[3], x[16];

	Decode(x, block, 64);

	/* Round 1 */
	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 */
	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 */
	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 */
	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 */

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

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

	/* Encodes input (UINT4) into output (unsigned char). Assumes len is
	a multiple of 4.
	*/
	static void Encode(unsigned char output, const UINT4 input, unsigned int len)
	{
	unsigned int i, j;
	UINT4 k;

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

	/* Decodes input (unsigned char) into output (UINT4). Assumes len is
	* a multiple of 4.
	*/
	static void Decode(UINT4 output, const unsigned char input, unsigned int len)
	{
	unsigned int i, j;

	for (i = 0, j = 0; j < len; i++, j += 4)
	output[i] = ((UINT4) input[j]) \| (((UINT4) input[j + 1]) << 8) \|
	(((UINT4) input[j + 2]) << 16) \| (((UINT4) input[j + 3]) << 24);
	}

	/*
	* Define the Magic String prefix that identifies a password as being
	* hashed using our algorithm.
	*/
	static const char *apr1_id = "$apr1$";

	/*
	* The following MD5 password encryption code was largely borrowed from
	* the FreeBSD 3.0 /usr/src/lib/libcrypt/crypt.c file, which is
	* licenced as stated at the top of this file.
	*/

	static void to64(char *s, unsigned long v, int n)
	{
	static unsigned char itoa64[] = /* 0 ... 63 => ASCII - 64 */
	"./0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";

	while (--n >= 0) {
	*s++ = itoa64[v&0x3f];
	v >>= 6;
	}
	}

	API_EXPORT(void) apr_MD5Encode(const char pw, const char salt,
	char *result, size_t nbytes)
	{
	/*
	* Minimum size is 8 bytes for salt, plus 1 for the trailing NUL,
	* plus 4 for the '$' separators, plus the password hash itself.
	* Let's leave a goodly amount of leeway.
	*/

	char passwd[120], *p;
	const char sp, ep;
	unsigned char final[16];
	int sl, pl, i;
	APR_MD5_CTX ctx, ctx1;
	unsigned long l;

	/*
	* Refine the salt first. It's possible we were given an already-hashed
	* string as the salt argument, so extract the actual salt value from it
	* if so. Otherwise just use the string up to the first '$' as the salt.
	*/
	sp = salt;

	/*
	* If it starts with the magic string, then skip that.
	*/
	if (!strncmp(sp, apr1_id, strlen(apr1_id))) {
	sp += strlen(apr1_id);
	}

	/*
	* It stops at the first '$' or 8 chars, whichever comes first
	*/
	for (ep = sp; (ep != '\0') && (ep != '$') && (ep < (sp + 8)); ep++) {
	continue;
	}

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

	/*
	* 'Time to make the doughnuts..'
	*/
	apr_MD5Init(&ctx);

	/*
	* The password first, since that is what is most unknown
	*/
	apr_MD5Update(&ctx, pw, strlen(pw));

	/*
	* Then our magic string
	*/
	apr_MD5Update(&ctx, apr1_id, strlen(apr1_id));

	/*
	* Then the raw salt
	*/
	apr_MD5Update(&ctx, sp, sl);

	/*
	* Then just as many characters of the MD5(pw, salt, pw)
	*/
	apr_MD5Init(&ctx1);
	apr_MD5Update(&ctx1, pw, strlen(pw));
	apr_MD5Update(&ctx1, sp, sl);
	apr_MD5Update(&ctx1, pw, strlen(pw));
	apr_MD5Final(final, &ctx1);
	for(pl = strlen(pw); pl > 0; pl -= 16) {
	apr_MD5Update(&ctx, final, (pl > 16) ? 16 : pl);
	}

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

	/*
	* Then something really weird...
	*/
	for (i = strlen(pw); i != 0; i >>= 1) {
	if (i & 1) {
	apr_MD5Update(&ctx, final, 1);
	}
	else {
	apr_MD5Update(&ctx, pw, 1);
	}
	}

	/*
	* Now make the output string. We know our limitations, so we
	* can use the string routines without bounds checking.
	*/
	strcpy(passwd, apr1_id);
	strncat(passwd, sp, sl);
	strcat(passwd, "$");

	apr_MD5Final(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++) {
	apr_MD5Init(&ctx1);
	if (i & 1) {
	apr_MD5Update(&ctx1, pw, strlen(pw));
	}
	else {
	apr_MD5Update(&ctx1, final, 16);
	}
	if (i % 3) {
	apr_MD5Update(&ctx1, sp, sl);
	}

	if (i % 7) {
	apr_MD5Update(&ctx1, pw, strlen(pw));
	}

	if (i & 1) {
	apr_MD5Update(&ctx1, final, 16);
	}
	else {
	apr_MD5Update(&ctx1, pw, strlen(pw));
	}
	apr_MD5Final(final,&ctx1);
	}

	p = passwd + strlen(passwd);

	l = (final[ 0]<<16) \| (final[ 6]<<8) \| final[12]; to64(p, l, 4); p += 4;
	l = (final[ 1]<<16) \| (final[ 7]<<8) \| final[13]; to64(p, l, 4); p += 4;
	l = (final[ 2]<<16) \| (final[ 8]<<8) \| final[14]; to64(p, l, 4); p += 4;
	l = (final[ 3]<<16) \| (final[ 9]<<8) \| final[15]; to64(p, l, 4); p += 4;
	l = (final[ 4]<<16) \| (final[10]<<8) \| final[ 5]; to64(p, l, 4); p += 4;
	l = final[11] ; to64(p, l, 2); p += 2;
	*p = '\0';

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

	apr_cpystrn(result, passwd, nbytes - 1);
	}

	/*
	* Validate a plaintext password against a smashed one. Use either
	* crypt() (if available) or apr_MD5Encode(), depending upon the format
	* of the smashed input password. Return NULL if they match, or
	* an explanatory text string if they don't.
	*/

	API_EXPORT(char ) apr_validate_password(const char passwd, const char *hash)
	{
	char sample[120];
	#ifndef WIN32
	char *crypt_pw;
	#endif
	if (!strncmp(hash, apr1_id, strlen(apr1_id))) {
	/*
	* The hash was created using our custom algorithm.
	*/
	apr_MD5Encode(passwd, hash, sample, sizeof(sample));
	}
	else {
	/*
	* It's not our algorithm, so feed it to crypt() if possible.
	*/
	#ifdef WIN32
	apr_cpystrn(sample, passwd, sizeof(sample) - 1);
	#else
	crypt_pw = crypt(passwd, hash);
	apr_cpystrn(sample, crypt_pw, sizeof(sample) - 1);
	#endif
	}
	return (strcmp(sample, hash) == 0) ? NULL : "password mismatch";
	}