bool AWSAuthV4Signer::SignRequest(Aws::Http::HttpRequest& request, bool signBody) const
{
    AWSCredentials credentials = m_credentialsProvider->GetAWSCredentials();

    //don't sign anonymous requests
    if (credentials.GetAWSAccessKeyId().empty() || credentials.GetAWSSecretKey().empty())
    {
        return true;
    }

    if (!credentials.GetSessionToken().empty())
    {
        request.SetAwsSessionToken(credentials.GetSessionToken());
    }

    Aws::String payloadHash(UNSIGNED_PAYLOAD);
    if(signBody || request.GetUri().GetScheme() != Http::Scheme::HTTPS)
    {
        payloadHash.assign(ComputePayloadHash(request));
        if (payloadHash.empty())
        {
            return false;
        }
    }
    else
    {
        AWS_LOGSTREAM_DEBUG(v4LogTag, "Note: Http payloads are not being signed. signPayloads=" << m_signPayloads
                << " http scheme=" << Http::SchemeMapper::ToString(request.GetUri().GetScheme()));
    }

    if(m_includeSha256HashHeader)
    {
        request.SetHeaderValue("x-amz-content-sha256", payloadHash);
    }

    //calculate date header to use in internal signature (this also goes into date header).
    DateTime now = GetSigningTimestamp();
    Aws::String dateHeaderValue = now.ToGmtString(LONG_DATE_FORMAT_STR);
    request.SetHeaderValue(AWS_DATE_HEADER, dateHeaderValue);

    Aws::StringStream headersStream;
    Aws::StringStream signedHeadersStream;

    for (const auto& header : CanonicalizeHeaders(request.GetHeaders()))
    {
        if(ShouldSignHeader(header.first))
        {
            headersStream << header.first.c_str() << ":" << header.second.c_str() << NEWLINE;
            signedHeadersStream << header.first.c_str() << ";";
        }
    }

    Aws::String canonicalHeadersString = headersStream.str();
    AWS_LOGSTREAM_DEBUG(v4LogTag, "Canonical Header String: " << canonicalHeadersString);

    //calculate signed headers parameter
    Aws::String signedHeadersValue = signedHeadersStream.str();
    //remove that last semi-colon
    signedHeadersValue.erase(signedHeadersValue.length() - 1);
    AWS_LOGSTREAM_DEBUG(v4LogTag, "Signed Headers value:" << signedHeadersValue);

    //generate generalized canonicalized request string.
    Aws::String canonicalRequestString = CanonicalizeRequestSigningString(request, m_urlEscapePath);

    //append v4 stuff to the canonical request string.
    canonicalRequestString.append(canonicalHeadersString);
    canonicalRequestString.append(NEWLINE);
    canonicalRequestString.append(signedHeadersValue);
    canonicalRequestString.append(NEWLINE);
    canonicalRequestString.append(payloadHash);

    AWS_LOGSTREAM_DEBUG(v4LogTag, "Canonical Request String: " << canonicalRequestString);

    //now compute sha256 on that request string
    auto hashResult = m_hash->Calculate(canonicalRequestString);
    if (!hashResult.IsSuccess())
    {
        AWS_LOGSTREAM_ERROR(v4LogTag, "Failed to hash (sha256) request string \"" << canonicalRequestString << "\"");
        return false;
    }

    auto sha256Digest = hashResult.GetResult();
    Aws::String cannonicalRequestHash = HashingUtils::HexEncode(sha256Digest);
    Aws::String simpleDate = now.ToGmtString(SIMPLE_DATE_FORMAT_STR);

    Aws::String stringToSign = GenerateStringToSign(dateHeaderValue, simpleDate, cannonicalRequestHash);
    auto finalSignature = GenerateSignature(credentials, stringToSign, simpleDate);

    Aws::StringStream ss;
    ss << AWS_HMAC_SHA256 << " " << CREDENTIAL << EQ << credentials.GetAWSAccessKeyId() << "/" << simpleDate
        << "/" << m_region << "/" << m_serviceName << "/" << AWS4_REQUEST << ", " << SIGNED_HEADERS << EQ
        << signedHeadersValue << ", " << SIGNATURE << EQ << finalSignature;

    auto awsAuthString = ss.str();
    AWS_LOGSTREAM_DEBUG(v4LogTag, "Signing request with: " << awsAuthString);
    request.SetAwsAuthorization(awsAuthString);

    return true;
}
Exemple #2
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std::shared_ptr<Aws::Http::HttpResponse> NetlibHttpClient::MakeRequest(
    Aws::Http::HttpRequest& request,
    Aws::Utils::RateLimits::RateLimiterInterface* readLimiter,
    Aws::Utils::RateLimits::RateLimiterInterface* writeLimiter) const {
  // AWS allows rate limiters to be passed around, but we are doing rate
  // limiting on the logger plugin side and so don't implement this.
  if (readLimiter != nullptr || writeLimiter != nullptr) {
    LOG(WARNING) << "Read/write limiters are unsupported";
  }

  Aws::Http::URI uri = request.GetUri();
  uri.SetPath(Aws::Http::URI::URLEncodePath(uri.GetPath()));
  Aws::String url = uri.GetURIString();

  bn::http::client client = TLSTransport().getClient();
  bn::http::client::request req(url);

  for (const auto& requestHeader : request.GetHeaders()) {
    req << bn::header(requestHeader.first, requestHeader.second);
  }

  std::string body;
  if (request.GetContentBody()) {
    std::stringstream ss;
    ss << request.GetContentBody()->rdbuf();
    body = ss.str();
  }

  auto response = std::make_shared<Standard::StandardHttpResponse>(request);
  try {
    bn::http::client::response resp;

    switch (request.GetMethod()) {
    case Aws::Http::HttpMethod::HTTP_GET:
      resp = client.get(req);
      if (resp.status() == 301 || resp.status() == 302) {
        VLOG(1) << "Attempting custom redirect as cpp-netlib does not support "
                   "redirects";
        for (const auto& header : resp.headers()) {
          if (header.first == "Location") {
            req.uri(header.second);
            resp = client.get(req);
          }
        }
      }
      break;
    case Aws::Http::HttpMethod::HTTP_POST:
      resp = client.post(req, body, request.GetContentType());
      break;
    case Aws::Http::HttpMethod::HTTP_PUT:
      resp = client.put(req, body, request.GetContentType());
      break;
    case Aws::Http::HttpMethod::HTTP_HEAD:
      resp = client.head(req);
      break;
    case Aws::Http::HttpMethod::HTTP_PATCH:
      LOG(ERROR) << "cpp-netlib does not support HTTP PATCH";
      return nullptr;
      break;
    case Aws::Http::HttpMethod::HTTP_DELETE:
      resp = client.delete_(req);
      break;
    default:
      LOG(ERROR) << "Unrecognized HTTP Method used: "
                 << static_cast<int>(request.GetMethod());
      return nullptr;
      break;
    }

    response->SetResponseCode(
        static_cast<Aws::Http::HttpResponseCode>(resp.status()));

    for (const auto& header : resp.headers()) {
      if (header.first == "content-type") {
        response->SetContentType(header.second);
      }
      response->AddHeader(header.first, header.second);
    }

    response->GetResponseBody() << resp.body();

  } catch (const std::exception& /*e*/) {
    LOG(ERROR) << "Exception making HTTP request to URL: " << url;
    return nullptr;
  }

  return response;
}