hphp/runtime/base/md5.h

   1 /*
   2    +----------------------------------------------------------------------+
   3    | HipHop for PHP                                                       |
   4    +----------------------------------------------------------------------+
   5    | Copyright (c) 2010-2013 Facebook, Inc. (http://www.facebook.com)     |
   6    | Copyright (c) 1998-2010 Zend Technologies Ltd. (http://www.zend.com) |
   7    +----------------------------------------------------------------------+
   8    | This source file is subject to version 2.00 of the Zend license,     |
   9    | that is bundled with this package in the file LICENSE, and is        |
  10    | available through the world-wide-web at the following url:           |
  11    | http://www.zend.com/license/2_00.txt.                                |
  12    | If you did not receive a copy of the Zend license and are unable to  |
  13    | obtain it through the world-wide-web, please send a note to          |
  14    | license@zend.com so we can mail you a copy immediately.              |
  15    +----------------------------------------------------------------------+
  16 */
  17
  18 #ifndef incl_HPHP_BASE_MD5_H_
  19 #define incl_HPHP_BASE_MD5_H_
  20
  21 #include "hphp/runtime/base/zend-string.h"
  22 #include "hphp/util/util.h"
  23
  24 namespace HPHP {
  25 /*
  26  * Most of php's infrastructure for md5sums treats them as strings. They
  27  * are 128-bits, though, and fit economically in a fixed-size struct.
  28  */
  29
  30 struct MD5 {
  31   uint64_t q[2];
  32   MD5() {
  33     q[0] = q[1] = 0;
  34   }
  35
  36   explicit MD5(const char* str) {
  37     // We expect our input to be null-terminated output from PHP::md5().
  38     assert(strlen(str) == 32);
  39     const int kQWordAsciiLen = 16;
  40     char buf[kQWordAsciiLen + 1];
  41     buf[kQWordAsciiLen] = 0;
  42     memcpy(buf, str, kQWordAsciiLen);
  43     assert(strlen(buf) == 16);
  44     q[0] = strtoull(buf, nullptr, 16);
  45
  46     memcpy(buf, str + kQWordAsciiLen, 16);
  47     assert(strlen(buf) == 16);
  48     q[1] = strtoull(buf, nullptr, 16);
  49   }
  50
  51   std::string toString() const {
  52     int len = 16;
  53     char md5nbo[16];
  54     nbo((void *)md5nbo);
  55     return std::string(string_bin2hex(md5nbo, len));
  56   }
  57
  58   // blob is assumed to be in network byte order.
  59   explicit MD5(const void* blob) {
  60     q[0] = ntohq(((const uint64_t*)blob)[0]);
  61     q[1] = ntohq(((const uint64_t*)blob)[1]);
  62   }
  63
  64   // Copy out in network byte order.
  65   void nbo(void* blob) const {
  66     ((uint64_t*)blob)[0] = htonq(q[0]);
  67     ((uint64_t*)blob)[1] = htonq(q[1]);
  68   }
  69
  70   bool isValid() const {
  71     /*
  72      * We arbitrarily choose kDefaultMD5 to be an "impossible" md5 value.
  73      * If someone manages to construct a PHP compilation unit that
  74      * collides, well, we owe them a pizza dinner or something.
  75      */
  76     return q[0] || q[1];
  77   }
  78
  79   bool operator==(const MD5& r) const {
  80     return q[0] == r.q[0] && q[1] == r.q[1];
  81   }
  82   bool operator<(const MD5& r) const {
  83     return q[0] < r.q[0] || (q[0] == r.q[0] && q[1] < r.q[1]);
  84   }
  85   bool operator>(const MD5& r) const {
  86     return q[0] > r.q[0] || (q[0] == r.q[0] && q[1] > r.q[1]);
  87   }
  88   bool operator!=(const MD5& r) const {
  89     return !operator==(r);
  90   }
  91
  92   uint64_t hash() const {
  93     // hash_int64_pair does way more work than necessary; all the bits here
  94     // are fantastically good.
  95     return q[0];
  96   }
  97 };
  98
  99 } // HPHP
 100 #endif
 101