jcs.org
Serenity Operating System
1/*
2 * Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
3 *
4 * SPDX-License-Identifier: BSD-2-Clause
5 */
6
7#pragma once
8
9#include <Kernel/Net/IPv4.h>
10
11namespace Kernel {
12
13struct TCPFlags {
14 enum : u16 {
15 FIN = 0x01,
16 SYN = 0x02,
17 RST = 0x04,
18 PSH = 0x08,
19 ACK = 0x10,
20 URG = 0x20
21 };
22};
23
24class [[gnu::packed]] TCPOptionMSS {
25public:
26 TCPOptionMSS(u16 value)
27 : m_value(value)
28 {
29 }
30
31 u16 value() const { return m_value; }
32
33private:
34 u8 m_option_kind { 0x02 };
35 u8 m_option_length { sizeof(TCPOptionMSS) };
36 NetworkOrdered<u16> m_value;
37};
38
39static_assert(AssertSize<TCPOptionMSS, 4>());
40
41class [[gnu::packed]] TCPPacket {
42public:
43 TCPPacket() = default;
44 ~TCPPacket() = default;
45
46 size_t header_size() const { return data_offset() * sizeof(u32); }
47
48 u16 source_port() const { return m_source_port; }
49 void set_source_port(u16 port) { m_source_port = port; }
50
51 u16 destination_port() const { return m_destination_port; }
52 void set_destination_port(u16 port) { m_destination_port = port; }
53
54 u32 sequence_number() const { return m_sequence_number; }
55 void set_sequence_number(u32 number) { m_sequence_number = number; }
56
57 u32 ack_number() const { return m_ack_number; }
58 void set_ack_number(u32 number) { m_ack_number = number; }
59
60 u16 flags() const { return m_flags_and_data_offset & 0x1ff; }
61 void set_flags(u16 flags) { m_flags_and_data_offset = (m_flags_and_data_offset & ~0x1ff) | (flags & 0x1ff); }
62
63 bool has_syn() const { return flags() & TCPFlags::SYN; }
64 bool has_ack() const { return flags() & TCPFlags::ACK; }
65 bool has_fin() const { return flags() & TCPFlags::FIN; }
66 bool has_rst() const { return flags() & TCPFlags::RST; }
67
68 u8 data_offset() const { return (m_flags_and_data_offset & 0xf000) >> 12; }
69 void set_data_offset(u16 data_offset) { m_flags_and_data_offset = (m_flags_and_data_offset & ~0xf000) | data_offset << 12; }
70
71 u16 window_size() const { return m_window_size; }
72 void set_window_size(u16 window_size) { m_window_size = window_size; }
73
74 u16 checksum() const { return m_checksum; }
75 void set_checksum(u16 checksum) { m_checksum = checksum; }
76
77 u16 urgent() const { return m_urgent; }
78 void set_urgent(u16 urgent) { m_urgent = urgent; }
79
80 void const* payload() const { return ((u8 const*)this) + header_size(); }
81 void* payload() { return ((u8*)this) + header_size(); }
82
83private:
84 NetworkOrdered<u16> m_source_port;
85 NetworkOrdered<u16> m_destination_port;
86 NetworkOrdered<u32> m_sequence_number;
87 NetworkOrdered<u32> m_ack_number;
88
89 NetworkOrdered<u16> m_flags_and_data_offset;
90 NetworkOrdered<u16> m_window_size;
91 NetworkOrdered<u16> m_checksum;
92 NetworkOrdered<u16> m_urgent;
93};
94
95static_assert(AssertSize<TCPPacket, 20>());
96
97}