xref: /freebsd/contrib/llvm-project/llvm/lib/Support/SHA1.cpp (revision ba3c1f5972d7b90feb6e6da47905ff2757e0fe57)
1 //====- SHA1.cpp - Private copy of the SHA1 implementation ---*- 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 //
9 // This code is taken from public domain
10 // (http://oauth.googlecode.com/svn/code/c/liboauth/src/sha1.c and
11 // http://cvsweb.netbsd.org/bsdweb.cgi/src/common/lib/libc/hash/sha1/sha1.c?rev=1.6)
12 // and modified by wrapping it in a C++ interface for LLVM,
13 // and removing unnecessary code.
14 //
15 //===----------------------------------------------------------------------===//
16 
17 #include "llvm/Support/SHA1.h"
18 #include "llvm/ADT/ArrayRef.h"
19 #include "llvm/ADT/StringRef.h"
20 #include "llvm/Support/Endian.h"
21 #include "llvm/Support/SwapByteOrder.h"
22 #include <string.h>
23 
24 using namespace llvm;
25 
26 static inline uint32_t rol(uint32_t Number, int Bits) {
27   return (Number << Bits) | (Number >> (32 - Bits));
28 }
29 
30 static inline uint32_t blk0(uint32_t *Buf, int I) { return Buf[I]; }
31 
32 static inline uint32_t blk(uint32_t *Buf, int I) {
33   Buf[I & 15] = rol(Buf[(I + 13) & 15] ^ Buf[(I + 8) & 15] ^ Buf[(I + 2) & 15] ^
34                         Buf[I & 15],
35                     1);
36   return Buf[I & 15];
37 }
38 
39 static inline void r0(uint32_t &A, uint32_t &B, uint32_t &C, uint32_t &D,
40                       uint32_t &E, int I, uint32_t *Buf) {
41   E += ((B & (C ^ D)) ^ D) + blk0(Buf, I) + 0x5A827999 + rol(A, 5);
42   B = rol(B, 30);
43 }
44 
45 static inline void r1(uint32_t &A, uint32_t &B, uint32_t &C, uint32_t &D,
46                       uint32_t &E, int I, uint32_t *Buf) {
47   E += ((B & (C ^ D)) ^ D) + blk(Buf, I) + 0x5A827999 + rol(A, 5);
48   B = rol(B, 30);
49 }
50 
51 static inline void r2(uint32_t &A, uint32_t &B, uint32_t &C, uint32_t &D,
52                       uint32_t &E, int I, uint32_t *Buf) {
53   E += (B ^ C ^ D) + blk(Buf, I) + 0x6ED9EBA1 + rol(A, 5);
54   B = rol(B, 30);
55 }
56 
57 static inline void r3(uint32_t &A, uint32_t &B, uint32_t &C, uint32_t &D,
58                       uint32_t &E, int I, uint32_t *Buf) {
59   E += (((B | C) & D) | (B & C)) + blk(Buf, I) + 0x8F1BBCDC + rol(A, 5);
60   B = rol(B, 30);
61 }
62 
63 static inline void r4(uint32_t &A, uint32_t &B, uint32_t &C, uint32_t &D,
64                       uint32_t &E, int I, uint32_t *Buf) {
65   E += (B ^ C ^ D) + blk(Buf, I) + 0xCA62C1D6 + rol(A, 5);
66   B = rol(B, 30);
67 }
68 
69 /* code */
70 #define SHA1_K0 0x5a827999
71 #define SHA1_K20 0x6ed9eba1
72 #define SHA1_K40 0x8f1bbcdc
73 #define SHA1_K60 0xca62c1d6
74 
75 #define SEED_0 0x67452301
76 #define SEED_1 0xefcdab89
77 #define SEED_2 0x98badcfe
78 #define SEED_3 0x10325476
79 #define SEED_4 0xc3d2e1f0
80 
81 void SHA1::init() {
82   InternalState.State[0] = SEED_0;
83   InternalState.State[1] = SEED_1;
84   InternalState.State[2] = SEED_2;
85   InternalState.State[3] = SEED_3;
86   InternalState.State[4] = SEED_4;
87   InternalState.ByteCount = 0;
88   InternalState.BufferOffset = 0;
89 }
90 
91 void SHA1::hashBlock() {
92   uint32_t A = InternalState.State[0];
93   uint32_t B = InternalState.State[1];
94   uint32_t C = InternalState.State[2];
95   uint32_t D = InternalState.State[3];
96   uint32_t E = InternalState.State[4];
97 
98   // 4 rounds of 20 operations each. Loop unrolled.
99   r0(A, B, C, D, E, 0, InternalState.Buffer.L);
100   r0(E, A, B, C, D, 1, InternalState.Buffer.L);
101   r0(D, E, A, B, C, 2, InternalState.Buffer.L);
102   r0(C, D, E, A, B, 3, InternalState.Buffer.L);
103   r0(B, C, D, E, A, 4, InternalState.Buffer.L);
104   r0(A, B, C, D, E, 5, InternalState.Buffer.L);
105   r0(E, A, B, C, D, 6, InternalState.Buffer.L);
106   r0(D, E, A, B, C, 7, InternalState.Buffer.L);
107   r0(C, D, E, A, B, 8, InternalState.Buffer.L);
108   r0(B, C, D, E, A, 9, InternalState.Buffer.L);
109   r0(A, B, C, D, E, 10, InternalState.Buffer.L);
110   r0(E, A, B, C, D, 11, InternalState.Buffer.L);
111   r0(D, E, A, B, C, 12, InternalState.Buffer.L);
112   r0(C, D, E, A, B, 13, InternalState.Buffer.L);
113   r0(B, C, D, E, A, 14, InternalState.Buffer.L);
114   r0(A, B, C, D, E, 15, InternalState.Buffer.L);
115   r1(E, A, B, C, D, 16, InternalState.Buffer.L);
116   r1(D, E, A, B, C, 17, InternalState.Buffer.L);
117   r1(C, D, E, A, B, 18, InternalState.Buffer.L);
118   r1(B, C, D, E, A, 19, InternalState.Buffer.L);
119 
120   r2(A, B, C, D, E, 20, InternalState.Buffer.L);
121   r2(E, A, B, C, D, 21, InternalState.Buffer.L);
122   r2(D, E, A, B, C, 22, InternalState.Buffer.L);
123   r2(C, D, E, A, B, 23, InternalState.Buffer.L);
124   r2(B, C, D, E, A, 24, InternalState.Buffer.L);
125   r2(A, B, C, D, E, 25, InternalState.Buffer.L);
126   r2(E, A, B, C, D, 26, InternalState.Buffer.L);
127   r2(D, E, A, B, C, 27, InternalState.Buffer.L);
128   r2(C, D, E, A, B, 28, InternalState.Buffer.L);
129   r2(B, C, D, E, A, 29, InternalState.Buffer.L);
130   r2(A, B, C, D, E, 30, InternalState.Buffer.L);
131   r2(E, A, B, C, D, 31, InternalState.Buffer.L);
132   r2(D, E, A, B, C, 32, InternalState.Buffer.L);
133   r2(C, D, E, A, B, 33, InternalState.Buffer.L);
134   r2(B, C, D, E, A, 34, InternalState.Buffer.L);
135   r2(A, B, C, D, E, 35, InternalState.Buffer.L);
136   r2(E, A, B, C, D, 36, InternalState.Buffer.L);
137   r2(D, E, A, B, C, 37, InternalState.Buffer.L);
138   r2(C, D, E, A, B, 38, InternalState.Buffer.L);
139   r2(B, C, D, E, A, 39, InternalState.Buffer.L);
140 
141   r3(A, B, C, D, E, 40, InternalState.Buffer.L);
142   r3(E, A, B, C, D, 41, InternalState.Buffer.L);
143   r3(D, E, A, B, C, 42, InternalState.Buffer.L);
144   r3(C, D, E, A, B, 43, InternalState.Buffer.L);
145   r3(B, C, D, E, A, 44, InternalState.Buffer.L);
146   r3(A, B, C, D, E, 45, InternalState.Buffer.L);
147   r3(E, A, B, C, D, 46, InternalState.Buffer.L);
148   r3(D, E, A, B, C, 47, InternalState.Buffer.L);
149   r3(C, D, E, A, B, 48, InternalState.Buffer.L);
150   r3(B, C, D, E, A, 49, InternalState.Buffer.L);
151   r3(A, B, C, D, E, 50, InternalState.Buffer.L);
152   r3(E, A, B, C, D, 51, InternalState.Buffer.L);
153   r3(D, E, A, B, C, 52, InternalState.Buffer.L);
154   r3(C, D, E, A, B, 53, InternalState.Buffer.L);
155   r3(B, C, D, E, A, 54, InternalState.Buffer.L);
156   r3(A, B, C, D, E, 55, InternalState.Buffer.L);
157   r3(E, A, B, C, D, 56, InternalState.Buffer.L);
158   r3(D, E, A, B, C, 57, InternalState.Buffer.L);
159   r3(C, D, E, A, B, 58, InternalState.Buffer.L);
160   r3(B, C, D, E, A, 59, InternalState.Buffer.L);
161 
162   r4(A, B, C, D, E, 60, InternalState.Buffer.L);
163   r4(E, A, B, C, D, 61, InternalState.Buffer.L);
164   r4(D, E, A, B, C, 62, InternalState.Buffer.L);
165   r4(C, D, E, A, B, 63, InternalState.Buffer.L);
166   r4(B, C, D, E, A, 64, InternalState.Buffer.L);
167   r4(A, B, C, D, E, 65, InternalState.Buffer.L);
168   r4(E, A, B, C, D, 66, InternalState.Buffer.L);
169   r4(D, E, A, B, C, 67, InternalState.Buffer.L);
170   r4(C, D, E, A, B, 68, InternalState.Buffer.L);
171   r4(B, C, D, E, A, 69, InternalState.Buffer.L);
172   r4(A, B, C, D, E, 70, InternalState.Buffer.L);
173   r4(E, A, B, C, D, 71, InternalState.Buffer.L);
174   r4(D, E, A, B, C, 72, InternalState.Buffer.L);
175   r4(C, D, E, A, B, 73, InternalState.Buffer.L);
176   r4(B, C, D, E, A, 74, InternalState.Buffer.L);
177   r4(A, B, C, D, E, 75, InternalState.Buffer.L);
178   r4(E, A, B, C, D, 76, InternalState.Buffer.L);
179   r4(D, E, A, B, C, 77, InternalState.Buffer.L);
180   r4(C, D, E, A, B, 78, InternalState.Buffer.L);
181   r4(B, C, D, E, A, 79, InternalState.Buffer.L);
182 
183   InternalState.State[0] += A;
184   InternalState.State[1] += B;
185   InternalState.State[2] += C;
186   InternalState.State[3] += D;
187   InternalState.State[4] += E;
188 }
189 
190 void SHA1::addUncounted(uint8_t Data) {
191   if constexpr (sys::IsBigEndianHost)
192     InternalState.Buffer.C[InternalState.BufferOffset] = Data;
193   else
194     InternalState.Buffer.C[InternalState.BufferOffset ^ 3] = Data;
195 
196   InternalState.BufferOffset++;
197   if (InternalState.BufferOffset == BLOCK_LENGTH) {
198     hashBlock();
199     InternalState.BufferOffset = 0;
200   }
201 }
202 
203 void SHA1::writebyte(uint8_t Data) {
204   ++InternalState.ByteCount;
205   addUncounted(Data);
206 }
207 
208 void SHA1::update(ArrayRef<uint8_t> Data) {
209   InternalState.ByteCount += Data.size();
210 
211   // Finish the current block.
212   if (InternalState.BufferOffset > 0) {
213     const size_t Remainder = std::min<size_t>(
214         Data.size(), BLOCK_LENGTH - InternalState.BufferOffset);
215     for (size_t I = 0; I < Remainder; ++I)
216       addUncounted(Data[I]);
217     Data = Data.drop_front(Remainder);
218   }
219 
220   // Fast buffer filling for large inputs.
221   while (Data.size() >= BLOCK_LENGTH) {
222     assert(InternalState.BufferOffset == 0);
223     static_assert(BLOCK_LENGTH % 4 == 0);
224     constexpr size_t BLOCK_LENGTH_32 = BLOCK_LENGTH / 4;
225     for (size_t I = 0; I < BLOCK_LENGTH_32; ++I)
226       InternalState.Buffer.L[I] = support::endian::read32be(&Data[I * 4]);
227     hashBlock();
228     Data = Data.drop_front(BLOCK_LENGTH);
229   }
230 
231   // Finish the remainder.
232   for (uint8_t C : Data)
233     addUncounted(C);
234 }
235 
236 void SHA1::update(StringRef Str) {
237   update(
238       ArrayRef<uint8_t>((uint8_t *)const_cast<char *>(Str.data()), Str.size()));
239 }
240 
241 void SHA1::pad() {
242   // Implement SHA-1 padding (fips180-2 5.1.1)
243 
244   // Pad with 0x80 followed by 0x00 until the end of the block
245   addUncounted(0x80);
246   while (InternalState.BufferOffset != 56)
247     addUncounted(0x00);
248 
249   // Append length in the last 8 bytes
250   addUncounted(0); // We're only using 32 bit lengths
251   addUncounted(0); // But SHA-1 supports 64 bit lengths
252   addUncounted(0); // So zero pad the top bits
253   addUncounted(InternalState.ByteCount >> 29); // Shifting to multiply by 8
254   addUncounted(InternalState.ByteCount >>
255                21); // as SHA-1 supports bitstreams as well as
256   addUncounted(InternalState.ByteCount >> 13); // byte.
257   addUncounted(InternalState.ByteCount >> 5);
258   addUncounted(InternalState.ByteCount << 3);
259 }
260 
261 void SHA1::final(std::array<uint32_t, HASH_LENGTH / 4> &HashResult) {
262   // Pad to complete the last block
263   pad();
264 
265   if constexpr (sys::IsBigEndianHost) {
266     // Just copy the current state
267     for (int i = 0; i < 5; i++) {
268       HashResult[i] = InternalState.State[i];
269     }
270   } else {
271     // Swap byte order back
272     for (int i = 0; i < 5; i++) {
273       HashResult[i] = sys::getSwappedBytes(InternalState.State[i]);
274     }
275   }
276 }
277 
278 std::array<uint8_t, 20> SHA1::final() {
279   union {
280     std::array<uint32_t, HASH_LENGTH / 4> HashResult;
281     std::array<uint8_t, HASH_LENGTH> ReturnResult;
282   };
283   static_assert(sizeof(HashResult) == sizeof(ReturnResult));
284   final(HashResult);
285   return ReturnResult;
286 }
287 
288 std::array<uint8_t, 20> SHA1::result() {
289   auto StateToRestore = InternalState;
290 
291   auto Hash = final();
292 
293   // Restore the state
294   InternalState = StateToRestore;
295 
296   // Return pointer to hash (20 characters)
297   return Hash;
298 }
299 
300 std::array<uint8_t, 20> SHA1::hash(ArrayRef<uint8_t> Data) {
301   SHA1 Hash;
302   Hash.update(Data);
303   return Hash.final();
304 }
305