path: root/contrib/libs/llvm12/lib/Support/SHA1.cpp

//====- SHA1.cpp - Private copy of the SHA1 implementation ---*- C++ -* ======// 
// 
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 
// See https://llvm.org/LICENSE.txt for license information. 
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 
// 
//===----------------------------------------------------------------------===// 
// 
// This code is taken from public domain 
// (http://oauth.googlecode.com/svn/code/c/liboauth/src/sha1.c and 
// http://cvsweb.netbsd.org/bsdweb.cgi/src/common/lib/libc/hash/sha1/sha1.c?rev=1.6) 
// and modified by wrapping it in a C++ interface for LLVM, 
// and removing unnecessary code. 
// 
//===----------------------------------------------------------------------===// 
 
#include "llvm/Support/SHA1.h" 
#include "llvm/ADT/ArrayRef.h" 
#include "llvm/ADT/StringRef.h" 
#include "llvm/Support/Endian.h" 
#include "llvm/Support/Host.h" 
#include <string.h> 
 
using namespace llvm; 
 
#if defined(BYTE_ORDER) && defined(BIG_ENDIAN) && BYTE_ORDER == BIG_ENDIAN 
#define SHA_BIG_ENDIAN 
#endif 
 
static inline uint32_t rol(uint32_t Number, int Bits) { 
  return (Number << Bits) | (Number >> (32 - Bits)); 
} 
 
static inline uint32_t blk0(uint32_t *Buf, int I) { return Buf[I]; } 
 
static inline uint32_t blk(uint32_t *Buf, int I) { 
  Buf[I & 15] = rol(Buf[(I + 13) & 15] ^ Buf[(I + 8) & 15] ^ Buf[(I + 2) & 15] ^ 
                        Buf[I & 15], 
                    1); 
  return Buf[I & 15]; 
} 
 
static inline void r0(uint32_t &A, uint32_t &B, uint32_t &C, uint32_t &D, 
                      uint32_t &E, int I, uint32_t *Buf) { 
  E += ((B & (C ^ D)) ^ D) + blk0(Buf, I) + 0x5A827999 + rol(A, 5); 
  B = rol(B, 30); 
} 
 
static inline void r1(uint32_t &A, uint32_t &B, uint32_t &C, uint32_t &D, 
                      uint32_t &E, int I, uint32_t *Buf) { 
  E += ((B & (C ^ D)) ^ D) + blk(Buf, I) + 0x5A827999 + rol(A, 5); 
  B = rol(B, 30); 
} 
 
static inline void r2(uint32_t &A, uint32_t &B, uint32_t &C, uint32_t &D, 
                      uint32_t &E, int I, uint32_t *Buf) { 
  E += (B ^ C ^ D) + blk(Buf, I) + 0x6ED9EBA1 + rol(A, 5); 
  B = rol(B, 30); 
} 
 
static inline void r3(uint32_t &A, uint32_t &B, uint32_t &C, uint32_t &D, 
                      uint32_t &E, int I, uint32_t *Buf) { 
  E += (((B | C) & D) | (B & C)) + blk(Buf, I) + 0x8F1BBCDC + rol(A, 5); 
  B = rol(B, 30); 
} 
 
static inline void r4(uint32_t &A, uint32_t &B, uint32_t &C, uint32_t &D, 
                      uint32_t &E, int I, uint32_t *Buf) { 
  E += (B ^ C ^ D) + blk(Buf, I) + 0xCA62C1D6 + rol(A, 5); 
  B = rol(B, 30); 
} 
 
/* code */ 
#define SHA1_K0 0x5a827999 
#define SHA1_K20 0x6ed9eba1 
#define SHA1_K40 0x8f1bbcdc 
#define SHA1_K60 0xca62c1d6 
 
#define SEED_0 0x67452301 
#define SEED_1 0xefcdab89 
#define SEED_2 0x98badcfe 
#define SEED_3 0x10325476 
#define SEED_4 0xc3d2e1f0 
 
void SHA1::init() { 
  InternalState.State[0] = SEED_0; 
  InternalState.State[1] = SEED_1; 
  InternalState.State[2] = SEED_2; 
  InternalState.State[3] = SEED_3; 
  InternalState.State[4] = SEED_4; 
  InternalState.ByteCount = 0; 
  InternalState.BufferOffset = 0; 
} 
 
void SHA1::hashBlock() { 
  uint32_t A = InternalState.State[0]; 
  uint32_t B = InternalState.State[1]; 
  uint32_t C = InternalState.State[2]; 
  uint32_t D = InternalState.State[3]; 
  uint32_t E = InternalState.State[4]; 
 
  // 4 rounds of 20 operations each. Loop unrolled. 
  r0(A, B, C, D, E, 0, InternalState.Buffer.L); 
  r0(E, A, B, C, D, 1, InternalState.Buffer.L); 
  r0(D, E, A, B, C, 2, InternalState.Buffer.L); 
  r0(C, D, E, A, B, 3, InternalState.Buffer.L); 
  r0(B, C, D, E, A, 4, InternalState.Buffer.L); 
  r0(A, B, C, D, E, 5, InternalState.Buffer.L); 
  r0(E, A, B, C, D, 6, InternalState.Buffer.L); 
  r0(D, E, A, B, C, 7, InternalState.Buffer.L); 
  r0(C, D, E, A, B, 8, InternalState.Buffer.L); 
  r0(B, C, D, E, A, 9, InternalState.Buffer.L); 
  r0(A, B, C, D, E, 10, InternalState.Buffer.L); 
  r0(E, A, B, C, D, 11, InternalState.Buffer.L); 
  r0(D, E, A, B, C, 12, InternalState.Buffer.L); 
  r0(C, D, E, A, B, 13, InternalState.Buffer.L); 
  r0(B, C, D, E, A, 14, InternalState.Buffer.L); 
  r0(A, B, C, D, E, 15, InternalState.Buffer.L); 
  r1(E, A, B, C, D, 16, InternalState.Buffer.L); 
  r1(D, E, A, B, C, 17, InternalState.Buffer.L); 
  r1(C, D, E, A, B, 18, InternalState.Buffer.L); 
  r1(B, C, D, E, A, 19, InternalState.Buffer.L); 
 
  r2(A, B, C, D, E, 20, InternalState.Buffer.L); 
  r2(E, A, B, C, D, 21, InternalState.Buffer.L); 
  r2(D, E, A, B, C, 22, InternalState.Buffer.L); 
  r2(C, D, E, A, B, 23, InternalState.Buffer.L); 
  r2(B, C, D, E, A, 24, InternalState.Buffer.L); 
  r2(A, B, C, D, E, 25, InternalState.Buffer.L); 
  r2(E, A, B, C, D, 26, InternalState.Buffer.L); 
  r2(D, E, A, B, C, 27, InternalState.Buffer.L); 
  r2(C, D, E, A, B, 28, InternalState.Buffer.L); 
  r2(B, C, D, E, A, 29, InternalState.Buffer.L); 
  r2(A, B, C, D, E, 30, InternalState.Buffer.L); 
  r2(E, A, B, C, D, 31, InternalState.Buffer.L); 
  r2(D, E, A, B, C, 32, InternalState.Buffer.L); 
  r2(C, D, E, A, B, 33, InternalState.Buffer.L); 
  r2(B, C, D, E, A, 34, InternalState.Buffer.L); 
  r2(A, B, C, D, E, 35, InternalState.Buffer.L); 
  r2(E, A, B, C, D, 36, InternalState.Buffer.L); 
  r2(D, E, A, B, C, 37, InternalState.Buffer.L); 
  r2(C, D, E, A, B, 38, InternalState.Buffer.L); 
  r2(B, C, D, E, A, 39, InternalState.Buffer.L); 
 
  r3(A, B, C, D, E, 40, InternalState.Buffer.L); 
  r3(E, A, B, C, D, 41, InternalState.Buffer.L); 
  r3(D, E, A, B, C, 42, InternalState.Buffer.L); 
  r3(C, D, E, A, B, 43, InternalState.Buffer.L); 
  r3(B, C, D, E, A, 44, InternalState.Buffer.L); 
  r3(A, B, C, D, E, 45, InternalState.Buffer.L); 
  r3(E, A, B, C, D, 46, InternalState.Buffer.L); 
  r3(D, E, A, B, C, 47, InternalState.Buffer.L); 
  r3(C, D, E, A, B, 48, InternalState.Buffer.L); 
  r3(B, C, D, E, A, 49, InternalState.Buffer.L); 
  r3(A, B, C, D, E, 50, InternalState.Buffer.L); 
  r3(E, A, B, C, D, 51, InternalState.Buffer.L); 
  r3(D, E, A, B, C, 52, InternalState.Buffer.L); 
  r3(C, D, E, A, B, 53, InternalState.Buffer.L); 
  r3(B, C, D, E, A, 54, InternalState.Buffer.L); 
  r3(A, B, C, D, E, 55, InternalState.Buffer.L); 
  r3(E, A, B, C, D, 56, InternalState.Buffer.L); 
  r3(D, E, A, B, C, 57, InternalState.Buffer.L); 
  r3(C, D, E, A, B, 58, InternalState.Buffer.L); 
  r3(B, C, D, E, A, 59, InternalState.Buffer.L); 
 
  r4(A, B, C, D, E, 60, InternalState.Buffer.L); 
  r4(E, A, B, C, D, 61, InternalState.Buffer.L); 
  r4(D, E, A, B, C, 62, InternalState.Buffer.L); 
  r4(C, D, E, A, B, 63, InternalState.Buffer.L); 
  r4(B, C, D, E, A, 64, InternalState.Buffer.L); 
  r4(A, B, C, D, E, 65, InternalState.Buffer.L); 
  r4(E, A, B, C, D, 66, InternalState.Buffer.L); 
  r4(D, E, A, B, C, 67, InternalState.Buffer.L); 
  r4(C, D, E, A, B, 68, InternalState.Buffer.L); 
  r4(B, C, D, E, A, 69, InternalState.Buffer.L); 
  r4(A, B, C, D, E, 70, InternalState.Buffer.L); 
  r4(E, A, B, C, D, 71, InternalState.Buffer.L); 
  r4(D, E, A, B, C, 72, InternalState.Buffer.L); 
  r4(C, D, E, A, B, 73, InternalState.Buffer.L); 
  r4(B, C, D, E, A, 74, InternalState.Buffer.L); 
  r4(A, B, C, D, E, 75, InternalState.Buffer.L); 
  r4(E, A, B, C, D, 76, InternalState.Buffer.L); 
  r4(D, E, A, B, C, 77, InternalState.Buffer.L); 
  r4(C, D, E, A, B, 78, InternalState.Buffer.L); 
  r4(B, C, D, E, A, 79, InternalState.Buffer.L); 
 
  InternalState.State[0] += A; 
  InternalState.State[1] += B; 
  InternalState.State[2] += C; 
  InternalState.State[3] += D; 
  InternalState.State[4] += E; 
} 
 
void SHA1::addUncounted(uint8_t Data) { 
#ifdef SHA_BIG_ENDIAN 
  InternalState.Buffer.C[InternalState.BufferOffset] = Data; 
#else 
  InternalState.Buffer.C[InternalState.BufferOffset ^ 3] = Data; 
#endif 
 
  InternalState.BufferOffset++; 
  if (InternalState.BufferOffset == BLOCK_LENGTH) { 
    hashBlock(); 
    InternalState.BufferOffset = 0; 
  } 
} 
 
void SHA1::writebyte(uint8_t Data) { 
  ++InternalState.ByteCount; 
  addUncounted(Data); 
} 
 
void SHA1::update(ArrayRef<uint8_t> Data) { 
  InternalState.ByteCount += Data.size(); 
 
  // Finish the current block. 
  if (InternalState.BufferOffset > 0) { 
    const size_t Remainder = std::min<size_t>( 
        Data.size(), BLOCK_LENGTH - InternalState.BufferOffset); 
    for (size_t I = 0; I < Remainder; ++I) 
      addUncounted(Data[I]); 
    Data = Data.drop_front(Remainder); 
  } 
 
  // Fast buffer filling for large inputs. 
  while (Data.size() >= BLOCK_LENGTH) { 
    assert(InternalState.BufferOffset == 0); 
    static_assert(BLOCK_LENGTH % 4 == 0, "");
    constexpr size_t BLOCK_LENGTH_32 = BLOCK_LENGTH / 4; 
    for (size_t I = 0; I < BLOCK_LENGTH_32; ++I) 
      InternalState.Buffer.L[I] = support::endian::read32be(&Data[I * 4]); 
    hashBlock(); 
    Data = Data.drop_front(BLOCK_LENGTH); 
  } 
 
  // Finish the remainder. 
  for (uint8_t C : Data) 
    addUncounted(C); 
} 
 
void SHA1::update(StringRef Str) { 
  update( 
      ArrayRef<uint8_t>((uint8_t *)const_cast<char *>(Str.data()), Str.size())); 
} 
 
void SHA1::pad() { 
  // Implement SHA-1 padding (fips180-2 5.1.1) 
 
  // Pad with 0x80 followed by 0x00 until the end of the block 
  addUncounted(0x80); 
  while (InternalState.BufferOffset != 56) 
    addUncounted(0x00); 
 
  // Append length in the last 8 bytes 
  addUncounted(0); // We're only using 32 bit lengths 
  addUncounted(0); // But SHA-1 supports 64 bit lengths 
  addUncounted(0); // So zero pad the top bits 
  addUncounted(InternalState.ByteCount >> 29); // Shifting to multiply by 8 
  addUncounted(InternalState.ByteCount >> 
               21); // as SHA-1 supports bitstreams as well as 
  addUncounted(InternalState.ByteCount >> 13); // byte. 
  addUncounted(InternalState.ByteCount >> 5); 
  addUncounted(InternalState.ByteCount << 3); 
} 
 
StringRef SHA1::final() { 
  // Pad to complete the last block 
  pad(); 
 
#ifdef SHA_BIG_ENDIAN 
  // Just copy the current state 
  for (int i = 0; i < 5; i++) { 
    HashResult[i] = InternalState.State[i]; 
  } 
#else 
  // Swap byte order back 
  for (int i = 0; i < 5; i++) { 
    HashResult[i] = (((InternalState.State[i]) << 24) & 0xff000000) | 
                    (((InternalState.State[i]) << 8) & 0x00ff0000) | 
                    (((InternalState.State[i]) >> 8) & 0x0000ff00) | 
                    (((InternalState.State[i]) >> 24) & 0x000000ff); 
  } 
#endif 
 
  // Return pointer to hash (20 characters) 
  return StringRef((char *)HashResult, HASH_LENGTH); 
} 
 
StringRef SHA1::result() { 
  auto StateToRestore = InternalState; 
 
  auto Hash = final(); 
 
  // Restore the state 
  InternalState = StateToRestore; 
 
  // Return pointer to hash (20 characters) 
  return Hash; 
} 
 
std::array<uint8_t, 20> SHA1::hash(ArrayRef<uint8_t> Data) { 
  SHA1 Hash; 
  Hash.update(Data); 
  StringRef S = Hash.final(); 
 
  std::array<uint8_t, 20> Arr; 
  memcpy(Arr.data(), S.data(), S.size()); 
  return Arr; 
}