1 /* 2 * Copyright 2006-2007, Haiku, Inc. All Rights Reserved. 3 * Distributed under the terms of the MIT License. 4 * 5 * Authors: 6 * Axel Dörfler, axeld@pinc-software.de 7 * Andrew Galante, haiku.galante@gmail.com 8 * Hugo Santos, hugosantos@gmail.com 9 */ 10 #ifndef TCP_H 11 #define TCP_H 12 13 14 #include <net_buffer.h> 15 #include <net_datalink.h> 16 #include <net_socket.h> 17 #include <net_stack.h> 18 19 #include <util/khash.h> 20 21 #include <ByteOrder.h> 22 23 #include <sys/socket.h> 24 25 26 class EndpointManager; 27 28 typedef enum { 29 // establishing a connection 30 CLOSED, 31 LISTEN, 32 SYNCHRONIZE_SENT, 33 SYNCHRONIZE_RECEIVED, 34 ESTABLISHED, 35 36 // peer closes the connection 37 FINISH_RECEIVED, 38 WAIT_FOR_FINISH_ACKNOWLEDGE, 39 40 // we close the connection 41 FINISH_SENT, 42 FINISH_ACKNOWLEDGED, 43 CLOSING, 44 TIME_WAIT 45 } tcp_state; 46 47 struct tcp_header { 48 uint16 source_port; 49 uint16 destination_port; 50 uint32 sequence; 51 uint32 acknowledge; 52 struct { 53 #if B_HOST_IS_LENDIAN == 1 54 uint8 reserved : 4; 55 uint8 header_length : 4; 56 #else 57 uint8 header_length : 4; 58 uint8 reserved : 4; 59 #endif 60 }; 61 uint8 flags; 62 uint16 advertised_window; 63 uint16 checksum; 64 uint16 urgent_offset; 65 66 uint32 HeaderLength() const { return (uint32)header_length << 2; } 67 uint32 Sequence() const { return ntohl(sequence); } 68 uint32 Acknowledge() const { return ntohl(acknowledge); } 69 uint16 AdvertisedWindow() const { return ntohs(advertised_window); } 70 uint16 Checksum() const { return ntohs(checksum); } 71 uint16 UrgentOffset() const { return ntohs(urgent_offset); } 72 } _PACKED; 73 74 class tcp_sequence { 75 public: 76 tcp_sequence() {} 77 tcp_sequence(uint32 sequence) : number(sequence) {} 78 79 operator uint32() const { return number; } 80 81 void operator=(uint32 sequence) { number = sequence; } 82 bool operator>(uint32 sequence) const { return (int32)(number - sequence) > 0; } 83 bool operator>=(uint32 sequence) const { return (int32)(number - sequence) >= 0; } 84 bool operator<(uint32 sequence) const { return (int32)(number - sequence) < 0; } 85 bool operator<=(uint32 sequence) const { return (int32)(number - sequence) <= 0; } 86 87 uint32& operator+=(uint32 sequence) { return number += sequence; } 88 uint32& operator++() { return ++number; } 89 uint32 operator++(int _) { return number++; } 90 91 private: 92 uint32 number; 93 }; 94 95 // TCP flag constants 96 #define TCP_FLAG_FINISH 0x01 97 #define TCP_FLAG_SYNCHRONIZE 0x02 98 #define TCP_FLAG_RESET 0x04 99 #define TCP_FLAG_PUSH 0x08 100 #define TCP_FLAG_ACKNOWLEDGE 0x10 101 #define TCP_FLAG_URGENT 0x20 102 #define TCP_FLAG_CONGESTION_NOTIFICATION_ECHO 0x40 103 #define TCP_FLAG_CONGESTION_WINDOW_REDUCED 0x80 104 105 #define TCP_CONNECTION_TIMEOUT 75000000 // 75 secs 106 #define TCP_DELAYED_ACKNOWLEDGE_TIMEOUT 100000 // 100 msecs 107 #define TCP_DEFAULT_MAX_SEGMENT_SIZE 536 108 #define TCP_MAX_WINDOW 65535 109 #define TCP_MAX_SEGMENT_LIFETIME 60000000 // 60 secs 110 111 struct tcp_sack { 112 uint32 left_edge; 113 uint32 right_edge; 114 } _PACKED; 115 116 struct tcp_option { 117 uint8 kind; 118 uint8 length; 119 union { 120 uint8 window_shift; 121 uint16 max_segment_size; 122 struct { 123 uint32 value; 124 uint32 reply; 125 } timestamp; 126 tcp_sack sack[0]; 127 }; 128 } _PACKED; 129 130 enum tcp_option_kind { 131 TCP_OPTION_END = 0, 132 TCP_OPTION_NOP = 1, 133 TCP_OPTION_MAX_SEGMENT_SIZE = 2, 134 TCP_OPTION_WINDOW_SHIFT = 3, 135 TCP_OPTION_SACK_PERMITTED = 4, 136 TCP_OPTION_SACK = 5, 137 TCP_OPTION_TIMESTAMP = 8, 138 }; 139 140 #define TCP_MAX_WINDOW_SHIFT 14 141 142 enum { 143 TCP_HAS_WINDOW_SCALE = 1 << 0, 144 TCP_HAS_TIMESTAMPS = 1 << 1, 145 TCP_SACK_PERMITTED = 1 << 2, 146 }; 147 148 struct tcp_segment_header { 149 tcp_segment_header(uint8 _flags) 150 : 151 flags(_flags), 152 window_shift(0), 153 max_segment_size(0), 154 sack_count(0), 155 options(0) 156 {} 157 158 uint32 sequence; 159 uint32 acknowledge; 160 uint16 advertised_window; 161 uint16 urgent_offset; 162 uint8 flags; 163 uint8 window_shift; 164 uint16 max_segment_size; 165 166 uint32 timestamp_value; 167 uint32 timestamp_reply; 168 169 tcp_sack *sacks; 170 int sack_count; 171 172 uint32 options; 173 174 bool AcknowledgeOnly() const 175 { 176 return (flags & (TCP_FLAG_SYNCHRONIZE | TCP_FLAG_FINISH | TCP_FLAG_RESET 177 | TCP_FLAG_URGENT | TCP_FLAG_ACKNOWLEDGE)) == TCP_FLAG_ACKNOWLEDGE; 178 } 179 }; 180 181 enum tcp_segment_action { 182 KEEP = 0x00, 183 DROP = 0x01, 184 RESET = 0x02, 185 ACKNOWLEDGE = 0x04, 186 IMMEDIATE_ACKNOWLEDGE = 0x08, 187 }; 188 189 190 extern net_buffer_module_info *gBufferModule; 191 extern net_datalink_module_info *gDatalinkModule; 192 extern net_socket_module_info *gSocketModule; 193 extern net_stack_module_info *gStackModule; 194 195 196 status_t add_tcp_header(net_address_module_info *addressModule, 197 tcp_segment_header &segment, net_buffer *buffer); 198 size_t tcp_options_length(tcp_segment_header &segment); 199 200 const char *name_for_state(tcp_state state); 201 202 EndpointManager *create_endpoint_manager(net_domain *domain); 203 void return_endpoint_manager(EndpointManager *); 204 205 #endif // TCP_H 206