1 | //==- SHA1.h - SHA1 implementation for LLVM --*- C++ -*-==// |
2 | // |
3 | // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
4 | // See https://llvm.org/LICENSE.txt for license information. |
5 | // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
6 | // |
7 | //===----------------------------------------------------------------------===// |
8 | // This code is taken from public domain |
9 | // (http://oauth.googlecode.com/svn/code/c/liboauth/src/sha1.c) |
10 | // and modified by wrapping it in a C++ interface for LLVM, |
11 | // and removing unnecessary code. |
12 | // |
13 | //===----------------------------------------------------------------------===// |
14 | |
15 | #ifndef LLVM_SUPPORT_SHA1_H |
16 | #define LLVM_SUPPORT_SHA1_H |
17 | |
18 | #include <array> |
19 | #include <cstdint> |
20 | |
21 | namespace llvm { |
22 | template <typename T> class ArrayRef; |
23 | class StringRef; |
24 | |
25 | /// A class that wrap the SHA1 algorithm. |
26 | class SHA1 { |
27 | public: |
28 | SHA1() { init(); } |
29 | |
30 | /// Reinitialize the internal state |
31 | void init(); |
32 | |
33 | /// Digest more data. |
34 | void update(ArrayRef<uint8_t> Data); |
35 | |
36 | /// Digest more data. |
37 | void update(StringRef Str); |
38 | |
39 | /// Return the current raw 160-bits SHA1 for the digested data |
40 | /// since the last call to init(). This call will add data to the internal |
41 | /// state and as such is not suited for getting an intermediate result |
42 | /// (see result()). |
43 | std::array<uint8_t, 20> final(); |
44 | |
45 | /// Return the current raw 160-bits SHA1 for the digested data |
46 | /// since the last call to init(). This is suitable for getting the SHA1 at |
47 | /// any time without invalidating the internal state so that more calls can be |
48 | /// made into update. |
49 | std::array<uint8_t, 20> result(); |
50 | |
51 | /// Returns a raw 160-bit SHA1 hash for the given data. |
52 | static std::array<uint8_t, 20> hash(ArrayRef<uint8_t> Data); |
53 | |
54 | private: |
55 | /// Define some constants. |
56 | /// "static constexpr" would be cleaner but MSVC does not support it yet. |
57 | enum { BLOCK_LENGTH = 64 }; |
58 | enum { HASH_LENGTH = 20 }; |
59 | |
60 | // Internal State |
61 | struct { |
62 | union { |
63 | uint8_t C[BLOCK_LENGTH]; |
64 | uint32_t L[BLOCK_LENGTH / 4]; |
65 | } Buffer; |
66 | uint32_t State[HASH_LENGTH / 4]; |
67 | uint32_t ByteCount; |
68 | uint8_t BufferOffset; |
69 | } InternalState; |
70 | |
71 | // Helper |
72 | void writebyte(uint8_t data); |
73 | void hashBlock(); |
74 | void addUncounted(uint8_t data); |
75 | void pad(); |
76 | |
77 | void final(std::array<uint32_t, HASH_LENGTH / 4> &HashResult); |
78 | }; |
79 | |
80 | } // end llvm namespace |
81 | |
82 | #endif |
83 | |