MD5.h revision 321369 
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
37namespace llvm {
38
39template <typename T> class ArrayRef;
40
41class 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
54public:
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  /// \brief Updates the hash for the byte stream provided.
85  void update(ArrayRef<uint8_t> Data);
86
87  /// \brief Updates the hash for the StringRef provided.
88  void update(StringRef Str);
89
90  /// \brief Finishes off the hash and puts the result in result.
91  void final(MD5Result &Result);
92
93  /// \brief 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  /// \brief Computes the hash for a given bytes.
98  static std::array<uint8_t, 16> hash(ArrayRef<uint8_t> Data);
99
100private:
101  const uint8_t *body(ArrayRef<uint8_t> Data);
102};
103
104inline 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.
109inline 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
123