include/llvm/Support/MD5.h

   1 /* -*- C++ -*-
   2  * This code is derived from (original license follows):
   3  *
   4  * This is an OpenSSL-compatible implementation of the RSA Data Security, Inc.
   5  * MD5 Message-Digest Algorithm (RFC 1321).
   6  *
   7  * Homepage:
   8  * http://openwall.info/wiki/people/solar/software/public-domain-source-code/md5
   9  *
  10  * Author:
  11  * Alexander Peslyak, better known as Solar Designer <solar at openwall.com>
  12  *
  13  * This software was written by Alexander Peslyak in 2001.  No copyright is
  14  * claimed, and the software is hereby placed in the public domain.
  15  * In case this attempt to disclaim copyright and place the software in the
  16  * public domain is deemed null and void, then the software is
  17  * Copyright (c) 2001 Alexander Peslyak and it is hereby released to the
  18  * general public under the following terms:
  19  *
  20  * Redistribution and use in source and binary forms, with or without
  21  * modification, are permitted.
  22  *
  23  * There's ABSOLUTELY NO WARRANTY, express or implied.
  24  *
  25  * See md5.c for more information.
  26  */
  27
  28 #ifndef LLVM_SUPPORT_MD5_H
  29 #define LLVM_SUPPORT_MD5_H
  30
  31 #include "llvm/ADT/SmallString.h"
  32 #include "llvm/ADT/StringRef.h"
  33 #include "llvm/Support/Endian.h"
  34 #include <array>
  35 #include <cstdint>
  36
  37 namespace llvm {
  38
  39 template <typename T> class ArrayRef;
  40
  41 class MD5 {
  42   // Any 32-bit or wider unsigned integer data type will do.
  43   typedef uint32_t MD5_u32plus;
  44
  45   MD5_u32plus a = 0x67452301;
  46   MD5_u32plus b = 0xefcdab89;
  47   MD5_u32plus c = 0x98badcfe;
  48   MD5_u32plus d = 0x10325476;
  49   MD5_u32plus hi = 0;
  50   MD5_u32plus lo = 0;
  51   uint8_t buffer[64];
  52   MD5_u32plus block[16];
  53
  54 public:
  55   struct MD5Result {
  56     std::array<uint8_t, 16> Bytes;
  57
  58     operator std::array<uint8_t, 16>() const { return Bytes; }
  59
  60     const uint8_t &operator[](size_t I) const { return Bytes[I]; }
  61     uint8_t &operator[](size_t I) { return Bytes[I]; }
  62
  63     SmallString<32> digest() const;
  64
  65     uint64_t low() const {
  66       // Our MD5 implementation returns the result in little endian, so the low
  67       // word is first.
  68       using namespace support;
  69       return endian::read<uint64_t, little, unaligned>(Bytes.data());
  70     }
  71
  72     uint64_t high() const {
  73       using namespace support;
  74       return endian::read<uint64_t, little, unaligned>(Bytes.data() + 8);
  75     }
  76     std::pair<uint64_t, uint64_t> words() const {
  77       using namespace support;
  78       return std::make_pair(high(), low());
  79     }
  80   };
  81
  82   MD5();
  83
  84   /// Updates the hash for the byte stream provided.
  85   void update(ArrayRef<uint8_t> Data);
  86
  87   /// Updates the hash for the StringRef provided.
  88   void update(StringRef Str);
  89
  90   /// Finishes off the hash and puts the result in result.
  91   void final(MD5Result &Result);
  92
  93   /// Translates the bytes in \p Res to a hex string that is
  94   /// deposited into \p Str. The result will be of length 32.
  95   static void stringifyResult(MD5Result &Result, SmallString<32> &Str);
  96
  97   /// Computes the hash for a given bytes.
  98   static std::array<uint8_t, 16> hash(ArrayRef<uint8_t> Data);
  99
 100 private:
 101   const uint8_t *body(ArrayRef<uint8_t> Data);
 102 };
 103
 104 inline bool operator==(const MD5::MD5Result &LHS, const MD5::MD5Result &RHS) {
 105   return LHS.Bytes == RHS.Bytes;
 106 }
 107
 108 /// Helper to compute and return lower 64 bits of the given string's MD5 hash.
 109 inline uint64_t MD5Hash(StringRef Str) {
 110   using namespace support;
 111
 112   MD5 Hash;
 113   Hash.update(Str);
 114   MD5::MD5Result Result;
 115   Hash.final(Result);
 116   // Return the least significant word.
 117   return Result.low();
 118 }
 119
 120 } // end namespace llvm
 121
 122 #endif // LLVM_SUPPORT_MD5_H