tcp.h 9.4 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231232233234235236237238239240241242243244245246247248249250251252253254255256257258259260261262263264265266267268269270271272273274275276277278279280281282283284285286287288289290291292293294295296297298299300301302303
  1. /* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */
  2. /*
  3. * INET An implementation of the TCP/IP protocol suite for the LINUX
  4. * operating system. INET is implemented using the BSD Socket
  5. * interface as the means of communication with the user level.
  6. *
  7. * Definitions for the TCP protocol.
  8. *
  9. * Version: @(#)tcp.h 1.0.2 04/28/93
  10. *
  11. * Author: Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
  12. *
  13. * This program is free software; you can redistribute it and/or
  14. * modify it under the terms of the GNU General Public License
  15. * as published by the Free Software Foundation; either version
  16. * 2 of the License, or (at your option) any later version.
  17. */
  18. #ifndef _UAPI_LINUX_TCP_H
  19. #define _UAPI_LINUX_TCP_H
  20. #include <linux/types.h>
  21. #include <asm/byteorder.h>
  22. #include <linux/socket.h>
  23. struct tcphdr {
  24. __be16 source;
  25. __be16 dest;
  26. __be32 seq;
  27. __be32 ack_seq;
  28. #if defined(__LITTLE_ENDIAN_BITFIELD)
  29. __u16 res1:4,
  30. doff:4,
  31. fin:1,
  32. syn:1,
  33. rst:1,
  34. psh:1,
  35. ack:1,
  36. urg:1,
  37. ece:1,
  38. cwr:1;
  39. #elif defined(__BIG_ENDIAN_BITFIELD)
  40. __u16 doff:4,
  41. res1:4,
  42. cwr:1,
  43. ece:1,
  44. urg:1,
  45. ack:1,
  46. psh:1,
  47. rst:1,
  48. syn:1,
  49. fin:1;
  50. #else
  51. #error "Adjust your <asm/byteorder.h> defines"
  52. #endif
  53. __be16 window;
  54. __sum16 check;
  55. __be16 urg_ptr;
  56. };
  57. /*
  58. * The union cast uses a gcc extension to avoid aliasing problems
  59. * (union is compatible to any of its members)
  60. * This means this part of the code is -fstrict-aliasing safe now.
  61. */
  62. union tcp_word_hdr {
  63. struct tcphdr hdr;
  64. __be32 words[5];
  65. };
  66. #define tcp_flag_word(tp) ( ((union tcp_word_hdr *)(tp))->words [3])
  67. enum {
  68. TCP_FLAG_CWR = __constant_cpu_to_be32(0x00800000),
  69. TCP_FLAG_ECE = __constant_cpu_to_be32(0x00400000),
  70. TCP_FLAG_URG = __constant_cpu_to_be32(0x00200000),
  71. TCP_FLAG_ACK = __constant_cpu_to_be32(0x00100000),
  72. TCP_FLAG_PSH = __constant_cpu_to_be32(0x00080000),
  73. TCP_FLAG_RST = __constant_cpu_to_be32(0x00040000),
  74. TCP_FLAG_SYN = __constant_cpu_to_be32(0x00020000),
  75. TCP_FLAG_FIN = __constant_cpu_to_be32(0x00010000),
  76. TCP_RESERVED_BITS = __constant_cpu_to_be32(0x0F000000),
  77. TCP_DATA_OFFSET = __constant_cpu_to_be32(0xF0000000)
  78. };
  79. /*
  80. * TCP general constants
  81. */
  82. #define TCP_MSS_DEFAULT 536U /* IPv4 (RFC1122, RFC2581) */
  83. #define TCP_MSS_DESIRED 1220U /* IPv6 (tunneled), EDNS0 (RFC3226) */
  84. /* TCP socket options */
  85. #define TCP_NODELAY 1 /* Turn off Nagle's algorithm. */
  86. #define TCP_MAXSEG 2 /* Limit MSS */
  87. #define TCP_CORK 3 /* Never send partially complete segments */
  88. #define TCP_KEEPIDLE 4 /* Start keeplives after this period */
  89. #define TCP_KEEPINTVL 5 /* Interval between keepalives */
  90. #define TCP_KEEPCNT 6 /* Number of keepalives before death */
  91. #define TCP_SYNCNT 7 /* Number of SYN retransmits */
  92. #define TCP_LINGER2 8 /* Life time of orphaned FIN-WAIT-2 state */
  93. #define TCP_DEFER_ACCEPT 9 /* Wake up listener only when data arrive */
  94. #define TCP_WINDOW_CLAMP 10 /* Bound advertised window */
  95. #define TCP_INFO 11 /* Information about this connection. */
  96. #define TCP_QUICKACK 12 /* Block/reenable quick acks */
  97. #define TCP_CONGESTION 13 /* Congestion control algorithm */
  98. #define TCP_MD5SIG 14 /* TCP MD5 Signature (RFC2385) */
  99. #define TCP_THIN_LINEAR_TIMEOUTS 16 /* Use linear timeouts for thin streams*/
  100. #define TCP_THIN_DUPACK 17 /* Fast retrans. after 1 dupack */
  101. #define TCP_USER_TIMEOUT 18 /* How long for loss retry before timeout */
  102. #define TCP_REPAIR 19 /* TCP sock is under repair right now */
  103. #define TCP_REPAIR_QUEUE 20
  104. #define TCP_QUEUE_SEQ 21
  105. #define TCP_REPAIR_OPTIONS 22
  106. #define TCP_FASTOPEN 23 /* Enable FastOpen on listeners */
  107. #define TCP_TIMESTAMP 24
  108. #define TCP_NOTSENT_LOWAT 25 /* limit number of unsent bytes in write queue */
  109. #define TCP_CC_INFO 26 /* Get Congestion Control (optional) info */
  110. #define TCP_SAVE_SYN 27 /* Record SYN headers for new connections */
  111. #define TCP_SAVED_SYN 28 /* Get SYN headers recorded for connection */
  112. #define TCP_REPAIR_WINDOW 29 /* Get/set window parameters */
  113. #define TCP_FASTOPEN_CONNECT 30 /* Attempt FastOpen with connect */
  114. #define TCP_ULP 31 /* Attach a ULP to a TCP connection */
  115. #define TCP_MD5SIG_EXT 32 /* TCP MD5 Signature with extensions */
  116. #define TCP_FASTOPEN_KEY 33 /* Set the key for Fast Open (cookie) */
  117. #define TCP_FASTOPEN_NO_COOKIE 34 /* Enable TFO without a TFO cookie */
  118. #define TCP_ZEROCOPY_RECEIVE 35
  119. #define TCP_INQ 36 /* Notify bytes available to read as a cmsg on read */
  120. #define TCP_CM_INQ TCP_INQ
  121. #define TCP_REPAIR_ON 1
  122. #define TCP_REPAIR_OFF 0
  123. #define TCP_REPAIR_OFF_NO_WP -1 /* Turn off without window probes */
  124. struct tcp_repair_opt {
  125. __u32 opt_code;
  126. __u32 opt_val;
  127. };
  128. struct tcp_repair_window {
  129. __u32 snd_wl1;
  130. __u32 snd_wnd;
  131. __u32 max_window;
  132. __u32 rcv_wnd;
  133. __u32 rcv_wup;
  134. };
  135. enum {
  136. TCP_NO_QUEUE,
  137. TCP_RECV_QUEUE,
  138. TCP_SEND_QUEUE,
  139. TCP_QUEUES_NR,
  140. };
  141. /* for TCP_INFO socket option */
  142. #define TCPI_OPT_TIMESTAMPS 1
  143. #define TCPI_OPT_SACK 2
  144. #define TCPI_OPT_WSCALE 4
  145. #define TCPI_OPT_ECN 8 /* ECN was negociated at TCP session init */
  146. #define TCPI_OPT_ECN_SEEN 16 /* we received at least one packet with ECT */
  147. #define TCPI_OPT_SYN_DATA 32 /* SYN-ACK acked data in SYN sent or rcvd */
  148. enum tcp_ca_state {
  149. TCP_CA_Open = 0,
  150. #define TCPF_CA_Open (1<<TCP_CA_Open)
  151. TCP_CA_Disorder = 1,
  152. #define TCPF_CA_Disorder (1<<TCP_CA_Disorder)
  153. TCP_CA_CWR = 2,
  154. #define TCPF_CA_CWR (1<<TCP_CA_CWR)
  155. TCP_CA_Recovery = 3,
  156. #define TCPF_CA_Recovery (1<<TCP_CA_Recovery)
  157. TCP_CA_Loss = 4
  158. #define TCPF_CA_Loss (1<<TCP_CA_Loss)
  159. };
  160. struct tcp_info {
  161. __u8 tcpi_state;
  162. __u8 tcpi_ca_state;
  163. __u8 tcpi_retransmits;
  164. __u8 tcpi_probes;
  165. __u8 tcpi_backoff;
  166. __u8 tcpi_options;
  167. __u8 tcpi_snd_wscale : 4, tcpi_rcv_wscale : 4;
  168. __u8 tcpi_delivery_rate_app_limited:1;
  169. __u32 tcpi_rto;
  170. __u32 tcpi_ato;
  171. __u32 tcpi_snd_mss;
  172. __u32 tcpi_rcv_mss;
  173. __u32 tcpi_unacked;
  174. __u32 tcpi_sacked;
  175. __u32 tcpi_lost;
  176. __u32 tcpi_retrans;
  177. __u32 tcpi_fackets;
  178. /* Times. */
  179. __u32 tcpi_last_data_sent;
  180. __u32 tcpi_last_ack_sent; /* Not remembered, sorry. */
  181. __u32 tcpi_last_data_recv;
  182. __u32 tcpi_last_ack_recv;
  183. /* Metrics. */
  184. __u32 tcpi_pmtu;
  185. __u32 tcpi_rcv_ssthresh;
  186. __u32 tcpi_rtt;
  187. __u32 tcpi_rttvar;
  188. __u32 tcpi_snd_ssthresh;
  189. __u32 tcpi_snd_cwnd;
  190. __u32 tcpi_advmss;
  191. __u32 tcpi_reordering;
  192. __u32 tcpi_rcv_rtt;
  193. __u32 tcpi_rcv_space;
  194. __u32 tcpi_total_retrans;
  195. __u64 tcpi_pacing_rate;
  196. __u64 tcpi_max_pacing_rate;
  197. __u64 tcpi_bytes_acked; /* RFC4898 tcpEStatsAppHCThruOctetsAcked */
  198. __u64 tcpi_bytes_received; /* RFC4898 tcpEStatsAppHCThruOctetsReceived */
  199. __u32 tcpi_segs_out; /* RFC4898 tcpEStatsPerfSegsOut */
  200. __u32 tcpi_segs_in; /* RFC4898 tcpEStatsPerfSegsIn */
  201. __u32 tcpi_notsent_bytes;
  202. __u32 tcpi_min_rtt;
  203. __u32 tcpi_data_segs_in; /* RFC4898 tcpEStatsDataSegsIn */
  204. __u32 tcpi_data_segs_out; /* RFC4898 tcpEStatsDataSegsOut */
  205. __u64 tcpi_delivery_rate;
  206. __u64 tcpi_busy_time; /* Time (usec) busy sending data */
  207. __u64 tcpi_rwnd_limited; /* Time (usec) limited by receive window */
  208. __u64 tcpi_sndbuf_limited; /* Time (usec) limited by send buffer */
  209. __u32 tcpi_delivered;
  210. __u32 tcpi_delivered_ce;
  211. __u64 tcpi_bytes_sent; /* RFC4898 tcpEStatsPerfHCDataOctetsOut */
  212. __u64 tcpi_bytes_retrans; /* RFC4898 tcpEStatsPerfOctetsRetrans */
  213. __u32 tcpi_dsack_dups; /* RFC4898 tcpEStatsStackDSACKDups */
  214. __u32 tcpi_reord_seen; /* reordering events seen */
  215. };
  216. /* netlink attributes types for SCM_TIMESTAMPING_OPT_STATS */
  217. enum {
  218. TCP_NLA_PAD,
  219. TCP_NLA_BUSY, /* Time (usec) busy sending data */
  220. TCP_NLA_RWND_LIMITED, /* Time (usec) limited by receive window */
  221. TCP_NLA_SNDBUF_LIMITED, /* Time (usec) limited by send buffer */
  222. TCP_NLA_DATA_SEGS_OUT, /* Data pkts sent including retransmission */
  223. TCP_NLA_TOTAL_RETRANS, /* Data pkts retransmitted */
  224. TCP_NLA_PACING_RATE, /* Pacing rate in bytes per second */
  225. TCP_NLA_DELIVERY_RATE, /* Delivery rate in bytes per second */
  226. TCP_NLA_SND_CWND, /* Sending congestion window */
  227. TCP_NLA_REORDERING, /* Reordering metric */
  228. TCP_NLA_MIN_RTT, /* minimum RTT */
  229. TCP_NLA_RECUR_RETRANS, /* Recurring retransmits for the current pkt */
  230. TCP_NLA_DELIVERY_RATE_APP_LMT, /* delivery rate application limited ? */
  231. TCP_NLA_SNDQ_SIZE, /* Data (bytes) pending in send queue */
  232. TCP_NLA_CA_STATE, /* ca_state of socket */
  233. TCP_NLA_SND_SSTHRESH, /* Slow start size threshold */
  234. TCP_NLA_DELIVERED, /* Data pkts delivered incl. out-of-order */
  235. TCP_NLA_DELIVERED_CE, /* Like above but only ones w/ CE marks */
  236. TCP_NLA_BYTES_SENT, /* Data bytes sent including retransmission */
  237. TCP_NLA_BYTES_RETRANS, /* Data bytes retransmitted */
  238. TCP_NLA_DSACK_DUPS, /* DSACK blocks received */
  239. TCP_NLA_REORD_SEEN, /* reordering events seen */
  240. };
  241. /* for TCP_MD5SIG socket option */
  242. #define TCP_MD5SIG_MAXKEYLEN 80
  243. /* tcp_md5sig extension flags for TCP_MD5SIG_EXT */
  244. #define TCP_MD5SIG_FLAG_PREFIX 1 /* address prefix length */
  245. struct tcp_md5sig {
  246. struct __kernel_sockaddr_storage tcpm_addr; /* address associated */
  247. __u8 tcpm_flags; /* extension flags */
  248. __u8 tcpm_prefixlen; /* address prefix */
  249. __u16 tcpm_keylen; /* key length */
  250. __u32 __tcpm_pad; /* zero */
  251. __u8 tcpm_key[TCP_MD5SIG_MAXKEYLEN]; /* key (binary) */
  252. };
  253. /* INET_DIAG_MD5SIG */
  254. struct tcp_diag_md5sig {
  255. __u8 tcpm_family;
  256. __u8 tcpm_prefixlen;
  257. __u16 tcpm_keylen;
  258. __be32 tcpm_addr[4];
  259. __u8 tcpm_key[TCP_MD5SIG_MAXKEYLEN];
  260. };
  261. /* setsockopt(fd, IPPROTO_TCP, TCP_ZEROCOPY_RECEIVE, ...) */
  262. struct tcp_zerocopy_receive {
  263. __u64 address; /* in: address of mapping */
  264. __u32 length; /* in/out: number of bytes to map/mapped */
  265. __u32 recv_skip_hint; /* out: amount of bytes to skip */
  266. };
  267. #endif /* _UAPI_LINUX_TCP_H */