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