xref: /aosp_15_r20/external/webrtc/net/dcsctp/packet/chunk/heartbeat_ack_chunk.cc (revision d9f758449e529ab9291ac668be2861e7a55c2422) 
1 /*
2  *  Copyright (c) 2021 The WebRTC project authors. All Rights Reserved.
3  *
4  *  Use of this source code is governed by a BSD-style license
5  *  that can be found in the LICENSE file in the root of the source
6  *  tree. An additional intellectual property rights grant can be found
7  *  in the file PATENTS.  All contributing project authors may
8  *  be found in the AUTHORS file in the root of the source tree.
9  */
10 #include "net/dcsctp/packet/chunk/heartbeat_ack_chunk.h"
11 
12 #include <stdint.h>
13 
14 #include <utility>
15 #include <vector>
16 
17 #include "absl/types/optional.h"
18 #include "api/array_view.h"
19 #include "net/dcsctp/packet/bounded_byte_reader.h"
20 #include "net/dcsctp/packet/bounded_byte_writer.h"
21 #include "net/dcsctp/packet/parameter/parameter.h"
22 #include "net/dcsctp/packet/tlv_trait.h"
23 
24 namespace dcsctp {
25 
26 // https://tools.ietf.org/html/rfc4960#section-3.3.6
27 
28 //   0                   1                   2                   3
29 //   0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
30 //  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
31 //  |   Type = 5    | Chunk  Flags  |    Heartbeat Ack Length       |
32 //  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
33 //  \                                                               \
34 //  /            Heartbeat Information TLV (Variable-Length)        /
35 //  \                                                               \
36 //  +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
37 constexpr int HeartbeatAckChunk::kType;
38 
Parse(rtc::ArrayView<const uint8_t> data)39 absl::optional<HeartbeatAckChunk> HeartbeatAckChunk::Parse(
40     rtc::ArrayView<const uint8_t> data) {
41   absl::optional<BoundedByteReader<kHeaderSize>> reader = ParseTLV(data);
42   if (!reader.has_value()) {
43     return absl::nullopt;
44   }
45 
46   absl::optional<Parameters> parameters =
47       Parameters::Parse(reader->variable_data());
48   if (!parameters.has_value()) {
49     return absl::nullopt;
50   }
51   return HeartbeatAckChunk(*std::move(parameters));
52 }
53 
SerializeTo(std::vector<uint8_t> & out) const54 void HeartbeatAckChunk::SerializeTo(std::vector<uint8_t>& out) const {
55   rtc::ArrayView<const uint8_t> parameters = parameters_.data();
56   BoundedByteWriter<kHeaderSize> writer = AllocateTLV(out, parameters.size());
57   writer.CopyToVariableData(parameters);
58 }
59 
ToString() const60 std::string HeartbeatAckChunk::ToString() const {
61   return "HEARTBEAT-ACK";
62 }
63 }  // namespace dcsctp
64