text: /*
   * Tencent is pleased to support the open source community by making IoT Hub available.
   * Copyright (C) 2018-2020 THL A29 Limited, a Tencent company. All rights reserved.
  
   * Licensed under the MIT License (the "License"); you may not use this file except in
   * compliance with the License. You may obtain a copy of the License at
   * http://opensource.org/licenses/MIT
  
   * Unless required by applicable law or agreed to in writing, software distributed under the License is
   * distributed on an "AS IS" basis, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
   * either express or implied. See the License for the specific language governing permissions and
   * limitations under the License.
   *
   */
  
  #include "utils_sha1.h"
  
  #include <stdlib.h>
  #include <string.h>
  
  #include "qcloud_iot_export_log.h"
  #include "qcloud_iot_import.h"
  
  /* Implementation that should never be optimized out by the compiler */
  static void utils_sha1_zeroize(void *v, size_t n)
  {
      volatile unsigned char *p = v;
      while (n--) {
          *p++ = 0;
      }
  }
  
  /*
   * 32-bit integer manipulation macros (big endian)
   */
  #ifndef IOT_SHA1_GET_UINT32_BE
  #define IOT_SHA1_GET_UINT32_BE(n, b, i)                                                                     \
      {                                                                                                       \
          (n) = ((uint32_t)(b)[(i)] << 24) | ((uint32_t)(b)[(i) + 1] << 16) | ((uint32_t)(b)[(i) + 2] << 8) | \
                ((uint32_t)(b)[(i) + 3]);                                                                     \
      }
  #endif
  
  #ifndef IOT_SHA1_PUT_UINT32_BE
  #define IOT_SHA1_PUT_UINT32_BE(n, b, i)            \
      {                                              \
          (b)[(i)]     = (unsigned char)((n) >> 24); \
          (b)[(i) + 1] = (unsigned char)((n) >> 16); \
          (b)[(i) + 2] = (unsigned char)((n) >> 8);  \
          (b)[(i) + 3] = (unsigned char)((n));       \
      }
  #endif
  
  void utils_sha1_init(iot_sha1_context *ctx)
  {
      memset(ctx, 0, sizeof(iot_sha1_context));
  }
  
  void utils_sha1_free(iot_sha1_context *ctx)
  {
      if (ctx == NULL) {
          return;
      }
  
      utils_sha1_zeroize(ctx, sizeof(iot_sha1_context));
  }
  
  void utils_sha1_clone(iot_sha1_context *dst, const iot_sha1_context *src)
  {
      *dst = *src;
  }
  
  /*
   * SHA-1 context setup
   */
  void utils_sha1_starts(iot_sha1_context *ctx)
  {
      ctx->total[0] = 0;
      ctx->total[1] = 0;
  
      ctx->state[0] = 0x67452301;
      ctx->state[1] = 0xEFCDAB89;
      ctx->state[2] = 0x98BADCFE;
      ctx->state[3] = 0x10325476;
      ctx->state[4] = 0xC3D2E1F0;
  }
  
  void utils_sha1_process(iot_sha1_context *ctx, const unsigned char data[64])
  {
      uint32_t temp, W[16], A, B, C, D, E;
  
      IOT_SHA1_GET_UINT32_BE(W[0], data, 0);
      IOT_SHA1_GET_UINT32_BE(W[1], data, 4);
      IOT_SHA1_GET_UINT32_BE(W[2], data, 8);
      IOT_SHA1_GET_UINT32_BE(W[3], data, 12);
      IOT_SHA1_GET_UINT32_BE(W[4], data, 16);
      IOT_SHA1_GET_UINT32_BE(W[5], data, 20);
      IOT_SHA1_GET_UINT32_BE(W[6], data, 24);
      IOT_SHA1_GET_UINT32_BE(W[7], data, 28);
      IOT_SHA1_GET_UINT32_BE(W[8], data, 32);
      IOT_SHA1_GET_UINT32_BE(W[9], data, 36);
      IOT_SHA1_GET_UINT32_BE(W[10], data, 40);
      IOT_SHA1_GET_UINT32_BE(W[11], data, 44);
      IOT_SHA1_GET_UINT32_BE(W[12], data, 48);
      IOT_SHA1_GET_UINT32_BE(W[13], data, 52);
      IOT_SHA1_GET_UINT32_BE(W[14], data, 56);
      IOT_SHA1_GET_UINT32_BE(W[15], data, 60);
  
  #define S(x, n) ((x << n) | ((x & 0xFFFFFFFF) >> (32 - n)))
  
  #define R(t) \
      (temp = W[(t - 3) & 0x0F] ^ W[(t - 8) & 0x0F] ^ W[(t - 14) & 0x0F] ^ W[t & 0x0F], (W[t & 0x0F] = S(temp, 1)))
  
  #define P(a, b, c, d, e, x)                \
      {                                      \
          e += S(a, 5) + F(b, c, d) + K + x; \
          b = S(b, 30);                      \
      }
  
      A = ctx->state[0];
      B = ctx->state[1];
      C = ctx->state[2];
      D = ctx->state[3];
      E = ctx->state[4];
  
  #define F(x, y, z) (z ^ (x & (y ^ z)))
  #define K          0x5A827999
  
      P(A, B, C, D, E, W[0]);
      P(E, A, B, C, D, W[1]);
      P(D, E, A, B, C, W[2]);
      P(C, D, E, A, B, W[3]);
      P(B, C, D, E, A, W[4]);
      P(A, B, C, D, E, W[5]);
      P(E, A, B, C, D, W[6]);
      P(D, E, A, B, C, W[7]);
      P(C, D, E, A, B, W[8]);
      P(B, C, D, E, A, W[9]);
      P(A, B, C, D, E, W[10]);
      P(E, A, B, C, D, W[11]);
      P(D, E, A, B, C, W[12]);
      P(C, D, E, A, B, W[13]);
      P(B, C, D, E, A, W[14]);
      P(A, B, C, D, E, W[15]);
      P(E, A, B, C, D, R(16));
      P(D, E, A, B, C, R(17));
      P(C, D, E, A, B, R(18));
      P(B, C, D, E, A, R(19));
  
  #undef K
  #undef F
  
  #define F(x, y, z) (x ^ y ^ z)
  #define K          0x6ED9EBA1
  
      P(A, B, C, D, E, R(20));
      P(E, A, B, C, D, R(21));
      P(D, E, A, B, C, R(22));
      P(C, D, E, A, B, R(23));
      P(B, C, D, E, A, R(24));
      P(A, B, C, D, E, R(25));
      P(E, A, B, C, D, R(26));
      P(D, E, A, B, C, R(27));
      P(C, D, E, A, B, R(28));
      P(B, C, D, E, A, R(29));
      P(A, B, C, D, E, R(30));
      P(E, A, B, C, D, R(31));
      P(D, E, A, B, C, R(32));
      P(C, D, E, A, B, R(33));
      P(B, C, D, E, A, R(34));
      P(A, B, C, D, E, R(35));
      P(E, A, B, C, D, R(36));
      P(D, E, A, B, C, R(37));
      P(C, D, E, A, B, R(38));
      P(B, C, D, E, A, R(39));
  
  #undef K
  #undef F
  
  #define F(x, y, z) ((x & y) | (z & (x | y)))
  #define K          0x8F1BBCDC
  
      P(A, B, C, D, E, R(40));
      P(E, A, B, C, D, R(41));
      P(D, E, A, B, C, R(42));
      P(C, D, E, A, B, R(43));
      P(B, C, D, E, A, R(44));
      P(A, B, C, D, E, R(45));
      P(E, A, B, C, D, R(46));
      P(D, E, A, B, C, R(47));
      P(C, D, E, A, B, R(48));
      P(B, C, D, E, A, R(49));
      P(A, B, C, D, E, R(50));
      P(E, A, B, C, D, R(51));
      P(D, E, A, B, C, R(52));
      P(C, D, E, A, B, R(53));
      P(B, C, D, E, A, R(54));
      P(A, B, C, D, E, R(55));
      P(E, A, B, C, D, R(56));
      P(D, E, A, B, C, R(57));
      P(C, D, E, A, B, R(58));
      P(B, C, D, E, A, R(59));
  
  #undef K
  #undef F
  
  #define F(x, y, z) (x ^ y ^ z)
  #define K          0xCA62C1D6
  
      P(A, B, C, D, E, R(60));
      P(E, A, B, C, D, R(61));
      P(D, E, A, B, C, R(62));
      P(C, D, E, A, B, R(63));
      P(B, C, D, E, A, R(64));
      P(A, B, C, D, E, R(65));
      P(E, A, B, C, D, R(66));
      P(D, E, A, B, C, R(67));
      P(C, D, E, A, B, R(68));
      P(B, C, D, E, A, R(69));
      P(A, B, C, D, E, R(70));
      P(E, A, B, C, D, R(71));
      P(D, E, A, B, C, R(72));
      P(C, D, E, A, B, R(73));
      P(B, C, D, E, A, R(74));
      P(A, B, C, D, E, R(75));
      P(E, A, B, C, D, R(76));
      P(D, E, A, B, C, R(77));
      P(C, D, E, A, B, R(78));
      P(B, C, D, E, A, R(79));
  
  #undef K
  #undef F
  
      ctx->state[0] += A;
      ctx->state[1] += B;
      ctx->state[2] += C;
      ctx->state[3] += D;
      ctx->state[4] += E;
  }
  
  /*
   * SHA-1 process buffer
   */
  void utils_sha1_update(iot_sha1_context *ctx, const unsigned char *input, size_t ilen)
  {
      size_t   fill;
      uint32_t left;
  
      if (ilen == 0) {
          return;
      }
  
      left = ctx->total[0] & 0x3F;
      fill = 64 - left;
  
      ctx->total[0] += (uint32_t)ilen;
      ctx->total[0] &= 0xFFFFFFFF;
  
      if (ctx->total[0] < (uint32_t)ilen) {
          ctx->total[1]++;
      }
  
      if (left && ilen >= fill) {
          memcpy((void *)(ctx->buffer + left), input, fill);
          utils_sha1_process(ctx, ctx->buffer);
          input += fill;
          ilen -= fill;
          left = 0;
      }
  
      while (ilen >= 64) {
          utils_sha1_process(ctx, input);
          input += 64;
          ilen -= 64;
      }
  
      if (ilen > 0) {
          memcpy((void *)(ctx->buffer + left), input, ilen);
      }
  }
  
  static const unsigned char iot_sha1_padding[64] = {0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
                                                     0,    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
                                                     0,    0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0};
  
  /*
   * SHA-1 final digest
   */
  void utils_sha1_finish(iot_sha1_context *ctx, unsigned char output[20])
  {
      uint32_t      last, padn;
      uint32_t      high, low;
      unsigned char msglen[8];
  
      high = (ctx->total[0] >> 29) | (ctx->total[1] << 3);
      low  = (ctx->total[0] << 3);
  
      IOT_SHA1_PUT_UINT32_BE(high, msglen, 0);
      IOT_SHA1_PUT_UINT32_BE(low, msglen, 4);
  
      last = ctx->total[0] & 0x3F;
      padn = (last < 56) ? (56 - last) : (120 - last);
  
      utils_sha1_update(ctx, iot_sha1_padding, padn);
      utils_sha1_update(ctx, msglen, 8);
  
      IOT_SHA1_PUT_UINT32_BE(ctx->state[0], output, 0);
      IOT_SHA1_PUT_UINT32_BE(ctx->state[1], output, 4);
      IOT_SHA1_PUT_UINT32_BE(ctx->state[2], output, 8);
      IOT_SHA1_PUT_UINT32_BE(ctx->state[3], output, 12);
      IOT_SHA1_PUT_UINT32_BE(ctx->state[4], output, 16);
  }
  
  /*
   * output = SHA-1( input buffer )
   */
  void utils_sha1(const unsigned char *input, size_t ilen, unsigned char output[20])
  {
      iot_sha1_context ctx;
  
      utils_sha1_init(&ctx);
      utils_sha1_starts(&ctx);
      utils_sha1_update(&ctx, input, ilen);
      utils_sha1_finish(&ctx, output);
      utils_sha1_free(&ctx);
  }
  