tcp.h 6.0 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212
  1. /*
  2. * INET An implementation of the TCP/IP protocol suite for the LINUX
  3. * operating system. INET is implemented using the BSD Socket
  4. * interface as the means of communication with the user level.
  5. *
  6. * Definitions for the TCP protocol.
  7. *
  8. * Version: @(#)tcp.h 1.0.2 04/28/93
  9. *
  10. * Author: Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
  11. *
  12. * This program is free software; you can redistribute it and/or
  13. * modify it under the terms of the GNU General Public License
  14. * as published by the Free Software Foundation; either version
  15. * 2 of the License, or (at your option) any later version.
  16. */
  17. #ifndef _LINUX_TCP_H
  18. #define _LINUX_TCP_H
  19. #include <linux/types.h>
  20. #include <asm/byteorder.h>
  21. #include <linux/socket.h>
  22. struct tcphdr {
  23. __be16 source;
  24. __be16 dest;
  25. __be32 seq;
  26. __be32 ack_seq;
  27. #if defined(__LITTLE_ENDIAN_BITFIELD)
  28. __u16 res1:4,
  29. doff:4,
  30. fin:1,
  31. syn:1,
  32. rst:1,
  33. psh:1,
  34. ack:1,
  35. urg:1,
  36. ece:1,
  37. cwr:1;
  38. #elif defined(__BIG_ENDIAN_BITFIELD)
  39. __u16 doff:4,
  40. res1:4,
  41. cwr:1,
  42. ece:1,
  43. urg:1,
  44. ack:1,
  45. psh:1,
  46. rst:1,
  47. syn:1,
  48. fin:1;
  49. #else
  50. #error "Adjust your <asm/byteorder.h> defines"
  51. #endif
  52. __be16 window;
  53. __sum16 check;
  54. __be16 urg_ptr;
  55. };
  56. /*
  57. * The union cast uses a gcc extension to avoid aliasing problems
  58. * (union is compatible to any of its members)
  59. * This means this part of the code is -fstrict-aliasing safe now.
  60. */
  61. union tcp_word_hdr {
  62. struct tcphdr hdr;
  63. __be32 words[5];
  64. };
  65. #define tcp_flag_word(tp) ( ((union tcp_word_hdr *)(tp))->words [3])
  66. enum {
  67. TCP_FLAG_CWR = __constant_cpu_to_be32(0x00800000),
  68. TCP_FLAG_ECE = __constant_cpu_to_be32(0x00400000),
  69. TCP_FLAG_URG = __constant_cpu_to_be32(0x00200000),
  70. TCP_FLAG_ACK = __constant_cpu_to_be32(0x00100000),
  71. TCP_FLAG_PSH = __constant_cpu_to_be32(0x00080000),
  72. TCP_FLAG_RST = __constant_cpu_to_be32(0x00040000),
  73. TCP_FLAG_SYN = __constant_cpu_to_be32(0x00020000),
  74. TCP_FLAG_FIN = __constant_cpu_to_be32(0x00010000),
  75. TCP_RESERVED_BITS = __constant_cpu_to_be32(0x0F000000),
  76. TCP_DATA_OFFSET = __constant_cpu_to_be32(0xF0000000)
  77. };
  78. /*
  79. * TCP general constants
  80. */
  81. #define TCP_MSS_DEFAULT 536U /* IPv4 (RFC1122, RFC2581) */
  82. #define TCP_MSS_DESIRED 1220U /* IPv6 (tunneled), EDNS0 (RFC3226) */
  83. /* TCP socket options */
  84. #define TCP_NODELAY 1 /* Turn off Nagle's algorithm. */
  85. #define TCP_MAXSEG 2 /* Limit MSS */
  86. #define TCP_CORK 3 /* Never send partially complete segments */
  87. #define TCP_KEEPIDLE 4 /* Start keeplives after this period */
  88. #define TCP_KEEPINTVL 5 /* Interval between keepalives */
  89. #define TCP_KEEPCNT 6 /* Number of keepalives before death */
  90. #define TCP_SYNCNT 7 /* Number of SYN retransmits */
  91. #define TCP_LINGER2 8 /* Life time of orphaned FIN-WAIT-2 state */
  92. #define TCP_DEFER_ACCEPT 9 /* Wake up listener only when data arrive */
  93. #define TCP_WINDOW_CLAMP 10 /* Bound advertised window */
  94. #define TCP_INFO 11 /* Information about this connection. */
  95. #define TCP_QUICKACK 12 /* Block/reenable quick acks */
  96. #define TCP_CONGESTION 13 /* Congestion control algorithm */
  97. #define TCP_MD5SIG 14 /* TCP MD5 Signature (RFC2385) */
  98. #define TCP_THIN_LINEAR_TIMEOUTS 16 /* Use linear timeouts for thin streams*/
  99. #define TCP_THIN_DUPACK 17 /* Fast retrans. after 1 dupack */
  100. #define TCP_USER_TIMEOUT 18 /* How long for loss retry before timeout */
  101. #define TCP_REPAIR 19 /* TCP sock is under repair right now */
  102. #define TCP_REPAIR_QUEUE 20
  103. #define TCP_QUEUE_SEQ 21
  104. #define TCP_REPAIR_OPTIONS 22
  105. #define TCP_FASTOPEN 23 /* Enable FastOpen on listeners */
  106. #define TCP_TIMESTAMP 24
  107. #define TCP_NOTSENT_LOWAT 25 /* limit number of unsent bytes in write queue */
  108. #define TCP_CC_INFO 26 /* Get Congestion Control (optional) info */
  109. #define TCP_SAVE_SYN 27 /* Record SYN headers for new connections */
  110. #define TCP_SAVED_SYN 28 /* Get SYN headers recorded for connection */
  111. struct tcp_repair_opt {
  112. __u32 opt_code;
  113. __u32 opt_val;
  114. };
  115. enum {
  116. TCP_NO_QUEUE,
  117. TCP_RECV_QUEUE,
  118. TCP_SEND_QUEUE,
  119. TCP_QUEUES_NR,
  120. };
  121. /* for TCP_INFO socket option */
  122. #define TCPI_OPT_TIMESTAMPS 1
  123. #define TCPI_OPT_SACK 2
  124. #define TCPI_OPT_WSCALE 4
  125. #define TCPI_OPT_ECN 8 /* ECN was negociated at TCP session init */
  126. #define TCPI_OPT_ECN_SEEN 16 /* we received at least one packet with ECT */
  127. #define TCPI_OPT_SYN_DATA 32 /* SYN-ACK acked data in SYN sent or rcvd */
  128. enum tcp_ca_state {
  129. TCP_CA_Open = 0,
  130. #define TCPF_CA_Open (1<<TCP_CA_Open)
  131. TCP_CA_Disorder = 1,
  132. #define TCPF_CA_Disorder (1<<TCP_CA_Disorder)
  133. TCP_CA_CWR = 2,
  134. #define TCPF_CA_CWR (1<<TCP_CA_CWR)
  135. TCP_CA_Recovery = 3,
  136. #define TCPF_CA_Recovery (1<<TCP_CA_Recovery)
  137. TCP_CA_Loss = 4
  138. #define TCPF_CA_Loss (1<<TCP_CA_Loss)
  139. };
  140. struct tcp_info {
  141. __u8 tcpi_state;
  142. __u8 tcpi_ca_state;
  143. __u8 tcpi_retransmits;
  144. __u8 tcpi_probes;
  145. __u8 tcpi_backoff;
  146. __u8 tcpi_options;
  147. __u8 tcpi_snd_wscale : 4, tcpi_rcv_wscale : 4;
  148. __u32 tcpi_rto;
  149. __u32 tcpi_ato;
  150. __u32 tcpi_snd_mss;
  151. __u32 tcpi_rcv_mss;
  152. __u32 tcpi_unacked;
  153. __u32 tcpi_sacked;
  154. __u32 tcpi_lost;
  155. __u32 tcpi_retrans;
  156. __u32 tcpi_fackets;
  157. /* Times. */
  158. __u32 tcpi_last_data_sent;
  159. __u32 tcpi_last_ack_sent; /* Not remembered, sorry. */
  160. __u32 tcpi_last_data_recv;
  161. __u32 tcpi_last_ack_recv;
  162. /* Metrics. */
  163. __u32 tcpi_pmtu;
  164. __u32 tcpi_rcv_ssthresh;
  165. __u32 tcpi_rtt;
  166. __u32 tcpi_rttvar;
  167. __u32 tcpi_snd_ssthresh;
  168. __u32 tcpi_snd_cwnd;
  169. __u32 tcpi_advmss;
  170. __u32 tcpi_reordering;
  171. __u32 tcpi_rcv_rtt;
  172. __u32 tcpi_rcv_space;
  173. __u32 tcpi_total_retrans;
  174. __u64 tcpi_pacing_rate;
  175. __u64 tcpi_max_pacing_rate;
  176. __u64 tcpi_bytes_acked; /* RFC4898 tcpEStatsAppHCThruOctetsAcked */
  177. __u64 tcpi_bytes_received; /* RFC4898 tcpEStatsAppHCThruOctetsReceived */
  178. __u32 tcpi_segs_out; /* RFC4898 tcpEStatsPerfSegsOut */
  179. __u32 tcpi_segs_in; /* RFC4898 tcpEStatsPerfSegsIn */
  180. };
  181. /* for TCP_MD5SIG socket option */
  182. #define TCP_MD5SIG_MAXKEYLEN 80
  183. struct tcp_md5sig {
  184. struct __kernel_sockaddr_storage tcpm_addr; /* address associated */
  185. __u16 __tcpm_pad1; /* zero */
  186. __u16 tcpm_keylen; /* key length */
  187. __u32 __tcpm_pad2; /* zero */
  188. __u8 tcpm_key[TCP_MD5SIG_MAXKEYLEN]; /* key (binary) */
  189. };
  190. #endif /* _LINUX_TCP_H */