/*

   +----------------------------------------------------------------------+

   | Copyright © The PHP Group and Contributors.                          |

   +----------------------------------------------------------------------+

   | This source file is subject to the Modified BSD License that is      |

   | bundled with this package in the file LICENSE, and is available      |

   | through the World Wide Web at <https://www.php.net/license/>.        |

   |                                                                      |

   | SPDX-License-Identifier: BSD-3-Clause                                |

   +----------------------------------------------------------------------+

   | Authors: Pierre Alain Joye  <pajoye@php.net                          |

   +----------------------------------------------------------------------+

 */

/*

 * License for the Unix md5crypt implementation (md5_crypt):

 *

 * ----------------------------------------------------------------------------

 * "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

 * ----------------------------------------------------------------------------

 *

 * from FreeBSD: crypt.c,v 1.5 1996/10/14 08:34:02 phk Exp

 * via OpenBSD: md5crypt.c,v 1.9 1997/07/23 20:58:27 kstailey Exp

 * via NetBSD: md5crypt.c,v 1.4.2.1 2002/01/22 19:31:59 he Exp

 *

 */

#include "php.h"

#include <string.h>

#ifdef PHP_WIN32

# include <windows.h>

# include <Wincrypt.h>

#endif

#include "php_crypt_r.h"

#include "crypt_freesec.h"

#include "ext/standard/md5.h"

#ifdef ZTS

MUTEX_T php_crypt_extended_init_lock;

#endif

void php_init_crypt_r(void)

{

#ifdef ZTS

  php_crypt_extended_init_lock = tsrm_mutex_alloc();

#endif

}

void php_shutdown_crypt_r(void)

{

#ifdef ZTS

  tsrm_mutex_free(php_crypt_extended_init_lock);

#endif

}

void _crypt_extended_init_r(void)

{

  static int initialized = 0;

#ifdef ZTS

  tsrm_mutex_lock(php_crypt_extended_init_lock);

#endif

  if (!initialized) {

    initialized = 1;

    _crypt_extended_init();

  }

#ifdef ZTS

  tsrm_mutex_unlock(php_crypt_extended_init_lock);

#endif

}

/* MD5 crypt implementation using the windows CryptoApi */

#define MD5_MAGIC "$1$"

#define MD5_MAGIC_LEN 3

static const unsigned char itoa64[] =   /* 0 ... 63 => ascii - 64 */

  "./0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";

/* Convert a 16/32 bit integer to Base64 string representation */

static void to64(char *s, int32_t v, int n)

{

  while (--n >= 0) {

    *s++ = itoa64[v & 0x3f];

    v >>= 6;

  }

}

/*

 * MD5 password encryption.

 */

char * php_md5_crypt_r(const char *pw, const char *salt, char *out)

{

  ZEND_TLS char passwd[MD5_HASH_MAX_LEN], *p;

  const char *sp, *ep;

  unsigned char final[16];

  unsigned int i, sl, pwl;

  PHP_MD5_CTX ctx, ctx1;

  uint32_t l;

  int pl;

  pwl = strlen(pw);

  /* Refine the salt first */

  sp = salt;

  /* If it starts with the magic string, then skip that */

  if (strncmp(sp, MD5_MAGIC, MD5_MAGIC_LEN) == 0)

    sp += MD5_MAGIC_LEN;

  /* It stops at the first '$', max 8 chars */

  for (ep = sp; *ep != '\0' && *ep != '$' && ep < (sp + 8); ep++);

  /* get the length of the true salt */

  sl = ep - sp;

  PHP_MD5Init(&ctx);

  /* The password first, since that is what is most unknown */

  PHP_MD5Update(&ctx, (const unsigned char *)pw, pwl);

  /* Then our magic string */

  PHP_MD5Update(&ctx, (const unsigned char *)MD5_MAGIC, MD5_MAGIC_LEN);

  /* Then the raw salt */

  PHP_MD5Update(&ctx, (const unsigned char *)sp, sl);

  /* Then just as many characters of the MD5(pw,salt,pw) */

  PHP_MD5Init(&ctx1);

  PHP_MD5Update(&ctx1, (const unsigned char *)pw, pwl);

  PHP_MD5Update(&ctx1, (const unsigned char *)sp, sl);

  PHP_MD5Update(&ctx1, (const unsigned char *)pw, pwl);

  PHP_MD5Final(final, &ctx1);

  for (pl = pwl; pl > 0; pl -= 16)

    PHP_MD5Update(&ctx, final, (unsigned int)(pl > 16 ? 16 : pl));

  /* Don't leave anything around in vm they could use. */

  ZEND_SECURE_ZERO(final, sizeof(final));

  /* Then something really weird... */

  for (i = pwl; i != 0; i >>= 1)

    if ((i & 1) != 0)

        PHP_MD5Update(&ctx, final, 1);

    else

        PHP_MD5Update(&ctx, (const unsigned char *)pw, 1);

  /* Now make the output string */

  memcpy(passwd, MD5_MAGIC, MD5_MAGIC_LEN);

  strlcpy(passwd + MD5_MAGIC_LEN, sp, sl + 1);

  strcat(passwd, "$");

  PHP_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++) {

    PHP_MD5Init(&ctx1);

    if ((i & 1) != 0)

      PHP_MD5Update(&ctx1, (const unsigned char *)pw, pwl);

    else

      PHP_MD5Update(&ctx1, final, 16);

    if ((i % 3) != 0)

      PHP_MD5Update(&ctx1, (const unsigned char *)sp, sl);

    if ((i % 7) != 0)

      PHP_MD5Update(&ctx1, (const unsigned char *)pw, pwl);

    if ((i & 1) != 0)

      PHP_MD5Update(&ctx1, final, 16);

    else

      PHP_MD5Update(&ctx1, (const unsigned char *)pw, pwl);

    PHP_MD5Final(final, &ctx1);

  }

  p = passwd + sl + MD5_MAGIC_LEN + 1;

  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. */

  ZEND_SECURE_ZERO(final, sizeof(final));

  return (passwd);

}