OTAInterfaceDefault.cpp

/*
  This file is part of the ArduinoIoTCloud library.

  Copyright (c) 2024 Arduino SA

  This Source Code Form is subject to the terms of the Mozilla Public
  License, v. 2.0. If a copy of the MPL was not distributed with this
  file, You can obtain one at http://mozilla.org/MPL/2.0/.
*/
#include <AIoTC_Config.h>

#if OTA_ENABLED && ! defined(OFFLOADED_DOWNLOAD)
#include "OTAInterfaceDefault.h"
#include "../OTA.h"

static uint32_t crc_update(uint32_t crc, const void * data, size_t data_len);

OTADefaultCloudProcessInterface::OTADefaultCloudProcessInterface(MessageStream *ms, Client* client)
: OTACloudProcessInterface(ms)
, client(client)
, http_client(nullptr)
, username(nullptr), password(nullptr)
, context(nullptr) {
}

OTADefaultCloudProcessInterface::~OTADefaultCloudProcessInterface() {
  reset();
}

OTACloudProcessInterface::State OTADefaultCloudProcessInterface::startOTA() {
  assert(client != nullptr);
  assert(OTACloudProcessInterface::context != nullptr);
  assert(context == nullptr);

  context = new Context(
    OTACloudProcessInterface::context->url,
    [this](uint8_t c) {
        if (this->writeFlash(&c, 1) != 1) {
          this->context->writeError = true;
        }
    }
  );

  // make the http get request
  if(strcmp(context->parsed_url.schema(), "https") == 0) {
    http_client = new HttpClient(*client, context->parsed_url.host(), context->parsed_url.port());
  } else {
    return UrlParseErrorFail;
  }

  http_client->beginRequest();
  auto res = http_client->get(context->parsed_url.path());

  if(username != nullptr && password != nullptr) {
    http_client->sendBasicAuth(username, password);
  }

  http_client->endRequest();

  if(res == HTTP_ERROR_CONNECTION_FAILED) {
    DEBUG_VERBOSE("OTA ERROR: http client error connecting to server \"%s:%d\"",
      context->parsed_url.host(), context->parsed_url.port());
    return ServerConnectErrorFail;
  } else if(res == HTTP_ERROR_TIMED_OUT) {
    DEBUG_VERBOSE("OTA ERROR: http client timeout \"%s\"", OTACloudProcessInterface::context->url);
    return OtaHeaderTimeoutFail;
  } else if(res != HTTP_SUCCESS) {
    DEBUG_VERBOSE("OTA ERROR: http client returned %d on  get \"%s\"", res, OTACloudProcessInterface::context->url);
    return OtaDownloadFail;
  }

  int statusCode = http_client->responseStatusCode();

  if(statusCode != 200) {
    DEBUG_VERBOSE("OTA ERROR: get response on \"%s\" returned status %d", OTACloudProcessInterface::context->url, statusCode);
    return HttpResponseFail;
  }

  // The following call is required to save the header value , keep it
  if(http_client->contentLength() == HttpClient::kNoContentLengthHeader) {
    DEBUG_VERBOSE("OTA ERROR: the response header doesn't contain \"ContentLength\" field");
    return HttpHeaderErrorFail;
  }

  context->lastReportTime = millis();

  return Fetch;
}

OTACloudProcessInterface::State OTADefaultCloudProcessInterface::fetch() {
  OTACloudProcessInterface::State res = Fetch;
  int http_res = 0;
  uint32_t start = millis();

  do {
    if(!http_client->connected()) {
      res = OtaDownloadFail;
      goto exit;
    }

    if(http_client->available() == 0) {
      /* Avoid tight loop and allow yield */
      delay(1);
      continue;
    }

    http_res = http_client->read(context->buffer, context->buf_len);

    if(http_res < 0) {
      DEBUG_VERBOSE("OTA ERROR: Download read error %d", http_res);
      res = OtaDownloadFail;
      goto exit;
    }

    parseOta(context->buffer, http_res);

    if(context->writeError) {
      DEBUG_VERBOSE("OTA ERROR: File write error");
      res = ErrorWriteUpdateFileFail;
      goto exit;
    }
  } while((context->downloadState == OtaDownloadFile || context->downloadState == OtaDownloadHeader) &&
    millis() - start < downloadTime);

  // TODO verify that the information present in the ota header match the info in context
  if(context->downloadState == OtaDownloadCompleted) {
    // Verify that the downloaded file size is matching the expected size ??
    // this could distinguish between consistency of the downloaded bytes and filesize

    // validate CRC
    context->calculatedCrc32 ^= 0xFFFFFFFF; // finalize CRC
    if(context->header.header.crc32 == context->calculatedCrc32) {
      DEBUG_VERBOSE("Ota download completed successfully");
      res = FlashOTA;
    } else {
      res = OtaHeaderCrcFail;
    }
  } else if(context->downloadState == OtaDownloadError) {
    DEBUG_VERBOSE("OTA ERROR: OtaDownloadError");

    res = OtaDownloadFail;
  } else if(context->downloadState == OtaDownloadMagicNumberMismatch) {
    DEBUG_VERBOSE("OTA ERROR: Magic number mismatch");
    res = OtaHeaderMagicNumberFail;
  }

exit:
  if(res != Fetch) {
    http_client->stop(); // close the connection
    delete http_client;
    http_client = nullptr;
  }
  return res;
}

void OTADefaultCloudProcessInterface::parseOta(uint8_t* buffer, size_t buf_len) {
  assert(context != nullptr); // This should never fail

  for(uint8_t* cursor=(uint8_t*)buffer; cursor<buffer+buf_len; ) {
    switch(context->downloadState) {
    case OtaDownloadHeader: {
      const uint32_t headerLeft = context->headerCopiedBytes + buf_len <= sizeof(context->header.buf) ? buf_len : sizeof(context->header.buf) - context->headerCopiedBytes;
      memcpy(context->header.buf+context->headerCopiedBytes, buffer, headerLeft);
      cursor += headerLeft;
      context->headerCopiedBytes += headerLeft;

      // when finished go to next state
      if(sizeof(context->header.buf) == context->headerCopiedBytes) {
        context->downloadState = OtaDownloadFile;

        context->calculatedCrc32 = crc_update(
          context->calculatedCrc32,
          &(context->header.header.magic_number),
          sizeof(context->header) - offsetof(ota::OTAHeader, header.magic_number)
        );

        if(context->header.header.magic_number != OtaMagicNumber) {
          context->downloadState = OtaDownloadMagicNumberMismatch;
          return;
        }
        context->downloadedSize += sizeof(context->header.buf);
      }

      break;
    }
    case OtaDownloadFile: {
      const uint32_t contentLength = http_client->contentLength();
      const uint32_t dataLeft = buf_len - (cursor-buffer);
      context->decoder.decompress(cursor, dataLeft); // TODO verify return value

      context->calculatedCrc32 = crc_update(
          context->calculatedCrc32,
          cursor,
          dataLeft
        );

      cursor += dataLeft;
      context->downloadedSize += dataLeft;

      if((millis() - context->lastReportTime) > 10000) { // Report the download progress each X millisecond
        DEBUG_VERBOSE("OTA Download Progress %d/%d", context->downloadedSize, contentLength);

        reportStatus(context->downloadedSize);
        context->lastReportTime = millis();
      }

      // TODO there should be no more bytes available when the download is completed
      if(context->downloadedSize == contentLength) {
        context->downloadState = OtaDownloadCompleted;
      }

      if(context->downloadedSize > contentLength) {
        context->downloadState = OtaDownloadError;
      }
      // TODO fail if we exceed a timeout? and available is 0 (client is broken)
      break;
    }
    case OtaDownloadCompleted:
      return;
    default:
      context->downloadState = OtaDownloadError;
      return;
    }
  }
}

void OTADefaultCloudProcessInterface::reset() {
  if(http_client != nullptr) {
    http_client->stop(); // close the connection
    delete http_client;
    http_client = nullptr;
  }

  if(client!=nullptr && client->connected()) {
    client->stop();
  }

  // free the context pointer
  if(context != nullptr) {
    delete context;
    context = nullptr;
  }
}

OTADefaultCloudProcessInterface::Context::Context(
  const char* url, std::function<void(uint8_t)> putc)
    : parsed_url(url)
    , downloadState(OtaDownloadHeader)
    , calculatedCrc32(0xFFFFFFFF)
    , headerCopiedBytes(0)
    , downloadedSize(0)
    , lastReportTime(0)
    , writeError(false)
    , decoder(putc) { }

static const uint32_t crc_table[256] = {
    0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, 0x076dc419, 0x706af48f, 0xe963a535, 0x9e6495a3,
    0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988, 0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, 0x90bf1d91,
    0x1db71064, 0x6ab020f2, 0xf3b97148, 0x84be41de, 0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7,
    0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec, 0x14015c4f, 0x63066cd9, 0xfa0f3d63, 0x8d080df5,
    0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172, 0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b,
    0x35b5a8fa, 0x42b2986c, 0xdbbbc9d6, 0xacbcf940, 0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59,
    0x26d930ac, 0x51de003a, 0xc8d75180, 0xbfd06116, 0x21b4f4b5, 0x56b3c423, 0xcfba9599, 0xb8bda50f,
    0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924, 0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d,
    0x76dc4190, 0x01db7106, 0x98d220bc, 0xefd5102a, 0x71b18589, 0x06b6b51f, 0x9fbfe4a5, 0xe8b8d433,
    0x7807c9a2, 0x0f00f934, 0x9609a88e, 0xe10e9818, 0x7f6a0dbb, 0x086d3d2d, 0x91646c97, 0xe6635c01,
    0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e, 0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457,
    0x65b0d9c6, 0x12b7e950, 0x8bbeb8ea, 0xfcb9887c, 0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65,
    0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2, 0x4adfa541, 0x3dd895d7, 0xa4d1c46d, 0xd3d6f4fb,
    0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0, 0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9,
    0x5005713c, 0x270241aa, 0xbe0b1010, 0xc90c2086, 0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f,
    0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4, 0x59b33d17, 0x2eb40d81, 0xb7bd5c3b, 0xc0ba6cad,
    0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a, 0xead54739, 0x9dd277af, 0x04db2615, 0x73dc1683,
    0xe3630b12, 0x94643b84, 0x0d6d6a3e, 0x7a6a5aa8, 0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1,
    0xf00f9344, 0x8708a3d2, 0x1e01f268, 0x6906c2fe, 0xf762575d, 0x806567cb, 0x196c3671, 0x6e6b06e7,
    0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc, 0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5,
    0xd6d6a3e8, 0xa1d1937e, 0x38d8c2c4, 0x4fdff252, 0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b,
    0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60, 0xdf60efc3, 0xa867df55, 0x316e8eef, 0x4669be79,
    0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236, 0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f,
    0xc5ba3bbe, 0xb2bd0b28, 0x2bb45a92, 0x5cb36a04, 0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d,
    0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x026d930a, 0x9c0906a9, 0xeb0e363f, 0x72076785, 0x05005713,
    0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38, 0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21,
    0x86d3d2d4, 0xf1d4e242, 0x68ddb3f8, 0x1fda836e, 0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777,
    0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c, 0x8f659eff, 0xf862ae69, 0x616bffd3, 0x166ccf45,
    0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2, 0xa7672661, 0xd06016f7, 0x4969474d, 0x3e6e77db,
    0xaed16a4a, 0xd9d65adc, 0x40df0b66, 0x37d83bf0, 0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9,
    0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6, 0xbad03605, 0xcdd70693, 0x54de5729, 0x23d967bf,
    0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94, 0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d
};

uint32_t crc_update(uint32_t crc, const void * data, size_t data_len) {
  const unsigned char *d = (const unsigned char *)data;
  unsigned int tbl_idx;

  while (data_len--) {
    tbl_idx = (crc ^ *d) & 0xff;
    crc = (crc_table[tbl_idx] ^ (crc >> 8)) & 0xffffffff;
    d++;
  }

  return crc & 0xffffffff;
}
#endif /* OTA_ENABLED && ! defined(OFFLOADED_DOWNLOAD) */