hphp/util/md5.h

   1 /*
   2    +----------------------------------------------------------------------+
   3    | HipHop for PHP                                                       |
   4    +----------------------------------------------------------------------+
   5    | Copyright (c) 2010-present 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/assertions.h"
  29 #include "hphp/util/byte-order.h"
  30
  31 namespace HPHP {
  32
  33 //////////////////////////////////////////////////////////////////////
  34
  35 struct MD5 : private boost::totally_ordered<MD5> {
  36   uint64_t q[2];
  37
  38   MD5() : q{} {}
  39
  40   // Input should be null-terminated output from PHP::md5().
  41   explicit MD5(folly::StringPiece str) {
  42     assertx(str.size() == 32);
  43     auto constexpr kQWordAsciiLen = 16;
  44     char buf[kQWordAsciiLen + 1];
  45     buf[kQWordAsciiLen] = '\0';
  46     memcpy(buf, str.begin(), kQWordAsciiLen);
  47     assertx(strlen(buf) == 16);
  48     q[0] = strtoull(buf, nullptr, 16);
  49
  50     memcpy(buf, str.begin() + kQWordAsciiLen, 16);
  51     assertx(strlen(buf) == 16);
  52     q[1] = strtoull(buf, nullptr, 16);
  53   }
  54
  55   // Blob is assumed to be in network byte order.
  56   explicit MD5(const void* blob, DEBUG_ONLY size_t len) {
  57     assertx(len == 16);
  58     q[0] = ntohq(((const uint64_t*)blob)[0]);
  59     q[1] = ntohq(((const uint64_t*)blob)[1]);
  60   }
  61
  62   explicit MD5(uint64_t x) {
  63     q[0] = 0; q[1] = x;
  64   }
  65
  66   // Copy out in network byte order.
  67   void nbo(void* blob) const {
  68     ((uint64_t*)blob)[0] = htonq(q[0]);
  69     ((uint64_t*)blob)[1] = htonq(q[1]);
  70   }
  71
  72   // Convert to a std::string with hex representation of the md5.
  73   std::string toString() const {
  74     std::string ret;
  75     char md5nbo[16];
  76     nbo(md5nbo);
  77     folly::hexlify(folly::StringPiece(md5nbo, sizeof md5nbo), ret);
  78     return ret;
  79   }
  80
  81   bool operator==(const MD5& r) const {
  82     return q[0] == r.q[0] && q[1] == r.q[1];
  83   }
  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
  89   uint64_t hash() const {
  90     // All the bits here are fantastically good.
  91     return q[0];
  92   }
  93 };
  94
  95 //////////////////////////////////////////////////////////////////////
  96
  97 }
  98
  99 #endif