1 //====- SHA256.cpp - SHA256 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 * The SHA-256 Secure Hash Standard was published by NIST in 2002.
10 *
11 * http://csrc.nist.gov/publications/fips/fips180-2/fips180-2.pdf
12 *
13 * The implementation is based on nacl's sha256 implementation [0] and LLVM's
14 * pre-exsiting SHA1 code [1].
15 *
16 * [0] https://hyperelliptic.org/nacl/nacl-20110221.tar.bz2 (public domain
17 * code)
18 * [1] llvm/lib/Support/SHA1.{h,cpp}
19 */
20 //===----------------------------------------------------------------------===//
21
22 #include "llvm/Support/SHA256.h"
23 #include "llvm/ADT/ArrayRef.h"
24 #include "llvm/ADT/StringRef.h"
25 #include "llvm/Support/Endian.h"
26 #include "llvm/Support/Host.h"
27 #include <string.h>
28
29 namespace llvm {
rol(uint32_t Number,int Bits)30
31 #if defined(BYTE_ORDER) && defined(BIG_ENDIAN) && BYTE_ORDER == BIG_ENDIAN
32 #define SHA_BIG_ENDIAN
33 #endif
34
35 #define SHR(x, c) ((x) >> (c))
36 #define ROTR(x, n) (((x) >> n) | ((x) << (32 - (n))))
37
38 #define CH(x, y, z) (((x) & (y)) ^ (~(x) & (z)))
39 #define MAJ(x, y, z) (((x) & (y)) ^ ((x) & (z)) ^ ((y) & (z)))
40
41 #define SIGMA_0(x) (ROTR(x, 2) ^ ROTR(x, 13) ^ ROTR(x, 22))
42 #define SIGMA_1(x) (ROTR(x, 6) ^ ROTR(x, 11) ^ ROTR(x, 25))
43
44 #define SIGMA_2(x) (ROTR(x, 17) ^ ROTR(x, 19) ^ SHR(x, 10))
45 #define SIGMA_3(x) (ROTR(x, 7) ^ ROTR(x, 18) ^ SHR(x, 3))
46
47 #define F_EXPAND(A, B, C, D, E, F, G, H, M1, M2, M3, M4, k) \
48 do { \
49 H += SIGMA_1(E) + CH(E, F, G) + M1 + k; \
50 D += H; \
51 H += SIGMA_0(A) + MAJ(A, B, C); \
52 M1 += SIGMA_2(M2) + M3 + SIGMA_3(M4); \
53 } while (0);
54
r2(uint32_t & A,uint32_t & B,uint32_t & C,uint32_t & D,uint32_t & E,int I,uint32_t * Buf)55 void SHA256::init() {
56 InternalState.State[0] = 0x6A09E667;
57 InternalState.State[1] = 0xBB67AE85;
58 InternalState.State[2] = 0x3C6EF372;
59 InternalState.State[3] = 0xA54FF53A;
60 InternalState.State[4] = 0x510E527F;
61 InternalState.State[5] = 0x9B05688C;
62 InternalState.State[6] = 0x1F83D9AB;
63 InternalState.State[7] = 0x5BE0CD19;
64 InternalState.ByteCount = 0;
65 InternalState.BufferOffset = 0;
66 }
r4(uint32_t & A,uint32_t & B,uint32_t & C,uint32_t & D,uint32_t & E,int I,uint32_t * Buf)67
68 void SHA256::hashBlock() {
69 uint32_t A = InternalState.State[0];
70 uint32_t B = InternalState.State[1];
71 uint32_t C = InternalState.State[2];
72 uint32_t D = InternalState.State[3];
73 uint32_t E = InternalState.State[4];
74 uint32_t F = InternalState.State[5];
75 uint32_t G = InternalState.State[6];
76 uint32_t H = InternalState.State[7];
77
78 uint32_t W00 = InternalState.Buffer.L[0];
79 uint32_t W01 = InternalState.Buffer.L[1];
80 uint32_t W02 = InternalState.Buffer.L[2];
81 uint32_t W03 = InternalState.Buffer.L[3];
82 uint32_t W04 = InternalState.Buffer.L[4];
83 uint32_t W05 = InternalState.Buffer.L[5];
84 uint32_t W06 = InternalState.Buffer.L[6];
85 uint32_t W07 = InternalState.Buffer.L[7];
86 uint32_t W08 = InternalState.Buffer.L[8];
87 uint32_t W09 = InternalState.Buffer.L[9];
88 uint32_t W10 = InternalState.Buffer.L[10];
89 uint32_t W11 = InternalState.Buffer.L[11];
90 uint32_t W12 = InternalState.Buffer.L[12];
91 uint32_t W13 = InternalState.Buffer.L[13];
92 uint32_t W14 = InternalState.Buffer.L[14];
93 uint32_t W15 = InternalState.Buffer.L[15];
94
95 F_EXPAND(A, B, C, D, E, F, G, H, W00, W14, W09, W01, 0x428A2F98);
96 F_EXPAND(H, A, B, C, D, E, F, G, W01, W15, W10, W02, 0x71374491);
97 F_EXPAND(G, H, A, B, C, D, E, F, W02, W00, W11, W03, 0xB5C0FBCF);
98 F_EXPAND(F, G, H, A, B, C, D, E, W03, W01, W12, W04, 0xE9B5DBA5);
99 F_EXPAND(E, F, G, H, A, B, C, D, W04, W02, W13, W05, 0x3956C25B);
100 F_EXPAND(D, E, F, G, H, A, B, C, W05, W03, W14, W06, 0x59F111F1);
101 F_EXPAND(C, D, E, F, G, H, A, B, W06, W04, W15, W07, 0x923F82A4);
102 F_EXPAND(B, C, D, E, F, G, H, A, W07, W05, W00, W08, 0xAB1C5ED5);
103 F_EXPAND(A, B, C, D, E, F, G, H, W08, W06, W01, W09, 0xD807AA98);
104 F_EXPAND(H, A, B, C, D, E, F, G, W09, W07, W02, W10, 0x12835B01);
105 F_EXPAND(G, H, A, B, C, D, E, F, W10, W08, W03, W11, 0x243185BE);
106 F_EXPAND(F, G, H, A, B, C, D, E, W11, W09, W04, W12, 0x550C7DC3);
107 F_EXPAND(E, F, G, H, A, B, C, D, W12, W10, W05, W13, 0x72BE5D74);
108 F_EXPAND(D, E, F, G, H, A, B, C, W13, W11, W06, W14, 0x80DEB1FE);
109 F_EXPAND(C, D, E, F, G, H, A, B, W14, W12, W07, W15, 0x9BDC06A7);
110 F_EXPAND(B, C, D, E, F, G, H, A, W15, W13, W08, W00, 0xC19BF174);
111
112 F_EXPAND(A, B, C, D, E, F, G, H, W00, W14, W09, W01, 0xE49B69C1);
113 F_EXPAND(H, A, B, C, D, E, F, G, W01, W15, W10, W02, 0xEFBE4786);
114 F_EXPAND(G, H, A, B, C, D, E, F, W02, W00, W11, W03, 0x0FC19DC6);
115 F_EXPAND(F, G, H, A, B, C, D, E, W03, W01, W12, W04, 0x240CA1CC);
116 F_EXPAND(E, F, G, H, A, B, C, D, W04, W02, W13, W05, 0x2DE92C6F);
117 F_EXPAND(D, E, F, G, H, A, B, C, W05, W03, W14, W06, 0x4A7484AA);
118 F_EXPAND(C, D, E, F, G, H, A, B, W06, W04, W15, W07, 0x5CB0A9DC);
119 F_EXPAND(B, C, D, E, F, G, H, A, W07, W05, W00, W08, 0x76F988DA);
120 F_EXPAND(A, B, C, D, E, F, G, H, W08, W06, W01, W09, 0x983E5152);
121 F_EXPAND(H, A, B, C, D, E, F, G, W09, W07, W02, W10, 0xA831C66D);
122 F_EXPAND(G, H, A, B, C, D, E, F, W10, W08, W03, W11, 0xB00327C8);
123 F_EXPAND(F, G, H, A, B, C, D, E, W11, W09, W04, W12, 0xBF597FC7);
124 F_EXPAND(E, F, G, H, A, B, C, D, W12, W10, W05, W13, 0xC6E00BF3);
125 F_EXPAND(D, E, F, G, H, A, B, C, W13, W11, W06, W14, 0xD5A79147);
126 F_EXPAND(C, D, E, F, G, H, A, B, W14, W12, W07, W15, 0x06CA6351);
127 F_EXPAND(B, C, D, E, F, G, H, A, W15, W13, W08, W00, 0x14292967);
128
129 F_EXPAND(A, B, C, D, E, F, G, H, W00, W14, W09, W01, 0x27B70A85);
130 F_EXPAND(H, A, B, C, D, E, F, G, W01, W15, W10, W02, 0x2E1B2138);
131 F_EXPAND(G, H, A, B, C, D, E, F, W02, W00, W11, W03, 0x4D2C6DFC);
132 F_EXPAND(F, G, H, A, B, C, D, E, W03, W01, W12, W04, 0x53380D13);
133 F_EXPAND(E, F, G, H, A, B, C, D, W04, W02, W13, W05, 0x650A7354);
134 F_EXPAND(D, E, F, G, H, A, B, C, W05, W03, W14, W06, 0x766A0ABB);
135 F_EXPAND(C, D, E, F, G, H, A, B, W06, W04, W15, W07, 0x81C2C92E);
136 F_EXPAND(B, C, D, E, F, G, H, A, W07, W05, W00, W08, 0x92722C85);
137 F_EXPAND(A, B, C, D, E, F, G, H, W08, W06, W01, W09, 0xA2BFE8A1);
138 F_EXPAND(H, A, B, C, D, E, F, G, W09, W07, W02, W10, 0xA81A664B);
139 F_EXPAND(G, H, A, B, C, D, E, F, W10, W08, W03, W11, 0xC24B8B70);
140 F_EXPAND(F, G, H, A, B, C, D, E, W11, W09, W04, W12, 0xC76C51A3);
141 F_EXPAND(E, F, G, H, A, B, C, D, W12, W10, W05, W13, 0xD192E819);
142 F_EXPAND(D, E, F, G, H, A, B, C, W13, W11, W06, W14, 0xD6990624);
143 F_EXPAND(C, D, E, F, G, H, A, B, W14, W12, W07, W15, 0xF40E3585);
144 F_EXPAND(B, C, D, E, F, G, H, A, W15, W13, W08, W00, 0x106AA070);
145
146 F_EXPAND(A, B, C, D, E, F, G, H, W00, W14, W09, W01, 0x19A4C116);
147 F_EXPAND(H, A, B, C, D, E, F, G, W01, W15, W10, W02, 0x1E376C08);
148 F_EXPAND(G, H, A, B, C, D, E, F, W02, W00, W11, W03, 0x2748774C);
149 F_EXPAND(F, G, H, A, B, C, D, E, W03, W01, W12, W04, 0x34B0BCB5);
150 F_EXPAND(E, F, G, H, A, B, C, D, W04, W02, W13, W05, 0x391C0CB3);
151 F_EXPAND(D, E, F, G, H, A, B, C, W05, W03, W14, W06, 0x4ED8AA4A);
152 F_EXPAND(C, D, E, F, G, H, A, B, W06, W04, W15, W07, 0x5B9CCA4F);
153 F_EXPAND(B, C, D, E, F, G, H, A, W07, W05, W00, W08, 0x682E6FF3);
154 F_EXPAND(A, B, C, D, E, F, G, H, W08, W06, W01, W09, 0x748F82EE);
155 F_EXPAND(H, A, B, C, D, E, F, G, W09, W07, W02, W10, 0x78A5636F);
156 F_EXPAND(G, H, A, B, C, D, E, F, W10, W08, W03, W11, 0x84C87814);
157 F_EXPAND(F, G, H, A, B, C, D, E, W11, W09, W04, W12, 0x8CC70208);
158 F_EXPAND(E, F, G, H, A, B, C, D, W12, W10, W05, W13, 0x90BEFFFA);
159 F_EXPAND(D, E, F, G, H, A, B, C, W13, W11, W06, W14, 0xA4506CEB);
160 F_EXPAND(C, D, E, F, G, H, A, B, W14, W12, W07, W15, 0xBEF9A3F7);
161 F_EXPAND(B, C, D, E, F, G, H, A, W15, W13, W08, W00, 0xC67178F2);
162
163 InternalState.State[0] += A;
164 InternalState.State[1] += B;
165 InternalState.State[2] += C;
166 InternalState.State[3] += D;
167 InternalState.State[4] += E;
168 InternalState.State[5] += F;
169 InternalState.State[6] += G;
170 InternalState.State[7] += H;
171 }
172
173 void SHA256::addUncounted(uint8_t Data) {
174 #ifdef SHA_BIG_ENDIAN
175 InternalState.Buffer.C[InternalState.BufferOffset] = Data;
176 #else
177 InternalState.Buffer.C[InternalState.BufferOffset ^ 3] = Data;
178 #endif
179
180 InternalState.BufferOffset++;
181 if (InternalState.BufferOffset == BLOCK_LENGTH) {
182 hashBlock();
183 InternalState.BufferOffset = 0;
184 }
185 }
186
187 void SHA256::writebyte(uint8_t Data) {
188 ++InternalState.ByteCount;
189 addUncounted(Data);
190 }
191
192 void SHA256::update(ArrayRef<uint8_t> Data) {
193 InternalState.ByteCount += Data.size();
addUncounted(uint8_t Data)194
195 // Finish the current block.
196 if (InternalState.BufferOffset > 0) {
197 const size_t Remainder = std::min<size_t>(
198 Data.size(), BLOCK_LENGTH - InternalState.BufferOffset);
199 for (size_t I = 0; I < Remainder; ++I)
200 addUncounted(Data[I]);
201 Data = Data.drop_front(Remainder);
202 }
203
204 // Fast buffer filling for large inputs.
205 while (Data.size() >= BLOCK_LENGTH) {
206 assert(InternalState.BufferOffset == 0);
207 static_assert(BLOCK_LENGTH % 4 == 0, "");
writebyte(uint8_t Data)208 constexpr size_t BLOCK_LENGTH_32 = BLOCK_LENGTH / 4;
209 for (size_t I = 0; I < BLOCK_LENGTH_32; ++I)
210 InternalState.Buffer.L[I] = support::endian::read32be(&Data[I * 4]);
211 hashBlock();
212 Data = Data.drop_front(BLOCK_LENGTH);
update(ArrayRef<uint8_t> Data)213 }
214
215 // Finish the remainder.
216 for (uint8_t C : Data)
217 addUncounted(C);
218 }
219
220 void SHA256::update(StringRef Str) {
221 update(
222 ArrayRef<uint8_t>((uint8_t *)const_cast<char *>(Str.data()), Str.size()));
223 }
224
225 void SHA256::pad() {
226 // Implement SHA-2 padding (fips180-2 5.1.1)
227
228 // Pad with 0x80 followed by 0x00 until the end of the block
229 addUncounted(0x80);
230 while (InternalState.BufferOffset != 56)
231 addUncounted(0x00);
232
233 uint64_t len = InternalState.ByteCount << 3; // bit size
234
235 // Append length in the last 8 bytes big edian encoded
236 addUncounted(len >> 56);
237 addUncounted(len >> 48);
238 addUncounted(len >> 40);
239 addUncounted(len >> 32);
240 addUncounted(len >> 24);
update(StringRef Str)241 addUncounted(len >> 16);
242 addUncounted(len >> 8);
243 addUncounted(len);
244 }
245
pad()246 StringRef SHA256::final() {
247 // Pad to complete the last block
248 pad();
249
250 #ifdef SHA_BIG_ENDIAN
251 // Just copy the current state
252 for (int i = 0; i < 8; i++) {
253 HashResult[i] = InternalState.State[i];
254 }
255 #else
256 // Swap byte order back
257 for (int i = 0; i < 8; i++) {
258 HashResult[i] = (((InternalState.State[i]) << 24) & 0xff000000) |
259 (((InternalState.State[i]) << 8) & 0x00ff0000) |
260 (((InternalState.State[i]) >> 8) & 0x0000ff00) |
261 (((InternalState.State[i]) >> 24) & 0x000000ff);
262 }
263 #endif
264
265 // Return pointer to hash (32 characters)
266 return StringRef((char *)HashResult, HASH_LENGTH);
267 }
268
269 StringRef SHA256::result() {
270 auto StateToRestore = InternalState;
271
272 auto Hash = final();
273
274 // Restore the state
275 InternalState = StateToRestore;
276
277 // Return pointer to hash (32 characters)
278 return Hash;
279 }
280
281 std::array<uint8_t, 32> SHA256::hash(ArrayRef<uint8_t> Data) {
282 SHA256 Hash;
283 Hash.update(Data);
284 StringRef S = Hash.final();
285
286 std::array<uint8_t, 32> Arr;
287 memcpy(Arr.data(), S.data(), S.size());
288 return Arr;
result()289 }
290
291 } // namespace llvm
292