1 // Copyright (c) 2019 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef QUICHE_QUIC_CORE_INTERNET_CHECKSUM_H_ 6 #define QUICHE_QUIC_CORE_INTERNET_CHECKSUM_H_ 7 8 #include <cstddef> 9 #include <cstdint> 10 11 #include "absl/strings/string_view.h" 12 #include "absl/types/span.h" 13 #include "quiche/common/platform/api/quiche_export.h" 14 15 namespace quic { 16 17 // Incrementally compute an Internet header checksum as described in RFC 1071. 18 class QUICHE_EXPORT InternetChecksum { 19 public: 20 // Update the checksum with the specified data. Note that while the checksum 21 // is commutative, the data has to be supplied in the units of two-byte words. 22 // If there is an extra byte at the end, the function has to be called on it 23 // last. 24 void Update(const char* data, size_t size); 25 void Update(const uint8_t* data, size_t size); 26 void Update(absl::string_view data); 27 void Update(absl::Span<const uint8_t> data); 28 29 uint16_t Value() const; 30 31 private: 32 uint32_t accumulator_ = 0; 33 }; 34 35 } // namespace quic 36 37 #endif // QUICHE_QUIC_CORE_INTERNET_CHECKSUM_H_ 38