llvm/lib/Support/SHA256.cpp

   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 {
  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
  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 }
  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();
 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, "");
 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);
 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);
 241   addUncounted(len >> 16);
 242   addUncounted(len >> 8);
 243   addUncounted(len);
 244 }
 245
 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;
 289 }
 290
 291 } // namespace llvm