components/apdu/apdu_response.cc

   1 // Copyright 2017 The Chromium Authors
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "components/apdu/apdu_response.h"
   6
   7 #include <utility>
   8
   9 #include "base/numerics/safe_conversions.h"
  10
  11 namespace apdu {
  12
  13 // static
  14 absl::optional<ApduResponse> ApduResponse::CreateFromMessage(
  15     base::span<const uint8_t> data) {
  16   // Invalid message size, data is appended by status byte.
  17   if (data.size() < 2)
  18     return absl::nullopt;
  19
  20   uint16_t status_bytes = data[data.size() - 2] << 8;
  21   status_bytes |= data[data.size() - 1];
  22
  23   return ApduResponse(std::vector<uint8_t>(data.begin(), data.end() - 2),
  24                       static_cast<Status>(status_bytes));
  25 }
  26
  27 ApduResponse::ApduResponse(std::vector<uint8_t> data, Status response_status)
  28     : data_(std::move(data)), response_status_(response_status) {}
  29
  30 ApduResponse::ApduResponse(ApduResponse&& that) = default;
  31
  32 ApduResponse& ApduResponse::operator=(ApduResponse&& that) = default;
  33
  34 ApduResponse::~ApduResponse() = default;
  35
  36 std::vector<uint8_t> ApduResponse::GetEncodedResponse() const {
  37   std::vector<uint8_t> encoded_response = data_;
  38   encoded_response.push_back(
  39       base::strict_cast<uint16_t>(response_status_) >> 8 & 0xff);
  40   encoded_response.push_back(base::strict_cast<uint16_t>(response_status_) &
  41                              0xff);
  42   return encoded_response;
  43 }
  44
  45 }  // namespace apdu