hphp/util/md5.h

   1 /*
   2    +----------------------------------------------------------------------+
   3    | HipHop for PHP                                                       |
   4    +----------------------------------------------------------------------+
   5    | Copyright (c) 2010-2015 Facebook, Inc. (http://www.facebook.com)     |
   6    +----------------------------------------------------------------------+
   7    | This source file is subject to version 3.01 of the PHP license,      |
   8    | that is bundled with this package in the file LICENSE, and is        |
   9    | available through the world-wide-web at the following url:           |
  10    | http://www.php.net/license/3_01.txt                                  |
  11    | If you did not receive a copy of the PHP license and are unable to   |
  12    | obtain it through the world-wide-web, please send a note to          |
  13    | license@php.net so we can mail you a copy immediately.               |
  14    +----------------------------------------------------------------------+
  15 */
  16
  17 #ifndef incl_HPHP_BASE_MD5_H_
  18 #define incl_HPHP_BASE_MD5_H_
  19
  20 #include <cstring>
  21 #include <memory>
  22
  23 #include <boost/operators.hpp>
  24
  25 #include <folly/String.h>
  26 #include <folly/Range.h>
  27
  28 #include "hphp/util/byte-order.h"
  29
  30 namespace HPHP {
  31
  32 //////////////////////////////////////////////////////////////////////
  33
  34 struct MD5 : private boost::totally_ordered<MD5> {
  35   uint64_t q[2];
  36
  37   MD5() : q{} {}
  38
  39   // Input should be null-terminated output from PHP::md5().
  40   explicit MD5(const char* str) {
  41     assert(strlen(str) == 32);
  42     const int kQWordAsciiLen = 16;
  43     char buf[kQWordAsciiLen + 1];
  44     buf[kQWordAsciiLen] = 0;
  45     memcpy(buf, str, kQWordAsciiLen);
  46     assert(strlen(buf) == 16);
  47     q[0] = strtoull(buf, nullptr, 16);
  48
  49     memcpy(buf, str + kQWordAsciiLen, 16);
  50     assert(strlen(buf) == 16);
  51     q[1] = strtoull(buf, nullptr, 16);
  52   }
  53
  54   // Blob is assumed to be in network byte order.
  55   explicit MD5(const void* blob) {
  56     q[0] = ntohq(((const uint64_t*)blob)[0]);
  57     q[1] = ntohq(((const uint64_t*)blob)[1]);
  58   }
  59
  60   // Copy out in network byte order.
  61   void nbo(void* blob) const {
  62     ((uint64_t*)blob)[0] = htonq(q[0]);
  63     ((uint64_t*)blob)[1] = htonq(q[1]);
  64   }
  65
  66   // Convert to a std::string with hex representation of the md5.
  67   std::string toString() const {
  68     std::string ret;
  69     char md5nbo[16];
  70     nbo(md5nbo);
  71     folly::hexlify(folly::StringPiece(md5nbo, sizeof md5nbo), ret);
  72     return ret;
  73   }
  74
  75   bool operator==(const MD5& r) const {
  76     return q[0] == r.q[0] && q[1] == r.q[1];
  77   }
  78
  79   bool operator<(const MD5& r) const {
  80     return q[0] < r.q[0] || (q[0] == r.q[0] && q[1] < r.q[1]);
  81   }
  82
  83   uint64_t hash() const {
  84     // hash_int64_pair does way more work than necessary; all the bits here
  85     // are fantastically good.
  86     return q[0];
  87   }
  88 };
  89
  90 //////////////////////////////////////////////////////////////////////
  91
  92 }
  93
  94 #endif
  95