Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 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 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 20 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 21 | #include <linux/skbuff.h> |
David Woodhouse | c8a553ad | 2006-06-22 14:28:09 -0700 | [diff] [blame] | 22 | #include <linux/dmaengine.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 23 | #include <net/sock.h> |
Arnaldo Carvalho de Melo | 463c84b | 2005-08-09 20:10:42 -0700 | [diff] [blame] | 24 | #include <net/inet_connection_sock.h> |
Arnaldo Carvalho de Melo | 8feaf0c0 | 2005-08-09 20:09:30 -0700 | [diff] [blame] | 25 | #include <net/inet_timewait_sock.h> |
David Howells | 607ca46 | 2012-10-13 10:46:48 +0100 | [diff] [blame] | 26 | #include <uapi/linux/tcp.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 27 | |
Arnaldo Carvalho de Melo | aa8223c | 2007-04-10 21:04:22 -0700 | [diff] [blame] | 28 | static inline struct tcphdr *tcp_hdr(const struct sk_buff *skb) |
| 29 | { |
Arnaldo Carvalho de Melo | 9c70220 | 2007-04-25 18:04:18 -0700 | [diff] [blame] | 30 | return (struct tcphdr *)skb_transport_header(skb); |
Arnaldo Carvalho de Melo | aa8223c | 2007-04-10 21:04:22 -0700 | [diff] [blame] | 31 | } |
| 32 | |
Arnaldo Carvalho de Melo | ab6a5bb | 2007-03-18 17:43:48 -0700 | [diff] [blame] | 33 | static inline unsigned int tcp_hdrlen(const struct sk_buff *skb) |
| 34 | { |
Arnaldo Carvalho de Melo | aa8223c | 2007-04-10 21:04:22 -0700 | [diff] [blame] | 35 | return tcp_hdr(skb)->doff * 4; |
Arnaldo Carvalho de Melo | ab6a5bb | 2007-03-18 17:43:48 -0700 | [diff] [blame] | 36 | } |
| 37 | |
| 38 | static inline unsigned int tcp_optlen(const struct sk_buff *skb) |
| 39 | { |
Arnaldo Carvalho de Melo | aa8223c | 2007-04-10 21:04:22 -0700 | [diff] [blame] | 40 | return (tcp_hdr(skb)->doff - 5) * 4; |
Arnaldo Carvalho de Melo | ab6a5bb | 2007-03-18 17:43:48 -0700 | [diff] [blame] | 41 | } |
| 42 | |
Yuchung Cheng | 2100c8d | 2012-07-19 06:43:05 +0000 | [diff] [blame] | 43 | /* TCP Fast Open */ |
| 44 | #define TCP_FASTOPEN_COOKIE_MIN 4 /* Min Fast Open Cookie size in bytes */ |
| 45 | #define TCP_FASTOPEN_COOKIE_MAX 16 /* Max Fast Open Cookie size in bytes */ |
Jerry Chu | 1046716 | 2012-08-31 12:29:11 +0000 | [diff] [blame] | 46 | #define TCP_FASTOPEN_COOKIE_SIZE 8 /* the size employed by this impl. */ |
Yuchung Cheng | 2100c8d | 2012-07-19 06:43:05 +0000 | [diff] [blame] | 47 | |
| 48 | /* TCP Fast Open Cookie as stored in memory */ |
| 49 | struct tcp_fastopen_cookie { |
| 50 | s8 len; |
| 51 | u8 val[TCP_FASTOPEN_COOKIE_MAX]; |
| 52 | }; |
| 53 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 54 | /* This defines a selective acknowledgement block. */ |
Al Viro | 269bd27 | 2006-09-27 18:32:28 -0700 | [diff] [blame] | 55 | struct tcp_sack_block_wire { |
| 56 | __be32 start_seq; |
| 57 | __be32 end_seq; |
| 58 | }; |
| 59 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 60 | struct tcp_sack_block { |
Arnaldo Carvalho de Melo | 3a137d2 | 2006-11-28 01:12:38 -0200 | [diff] [blame] | 61 | u32 start_seq; |
| 62 | u32 end_seq; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 63 | }; |
| 64 | |
Vijay Subramanian | ab56222 | 2011-12-20 13:23:24 +0000 | [diff] [blame] | 65 | /*These are used to set the sack_ok field in struct tcp_options_received */ |
| 66 | #define TCP_SACK_SEEN (1 << 0) /*1 = peer is SACK capable, */ |
| 67 | #define TCP_FACK_ENABLED (1 << 1) /*1 = FACK is enabled locally*/ |
| 68 | #define TCP_DSACK_SEEN (1 << 2) /*1 = DSACK was received from peer*/ |
| 69 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 70 | struct tcp_options_received { |
| 71 | /* PAWS/RTTM data */ |
| 72 | long ts_recent_stamp;/* Time we stored ts_recent (for aging) */ |
Arnaldo Carvalho de Melo | 3a137d2 | 2006-11-28 01:12:38 -0200 | [diff] [blame] | 73 | u32 ts_recent; /* Time stamp to echo next */ |
| 74 | u32 rcv_tsval; /* Time stamp value */ |
| 75 | u32 rcv_tsecr; /* Time stamp echo reply */ |
| 76 | u16 saw_tstamp : 1, /* Saw TIMESTAMP on last packet */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 77 | tstamp_ok : 1, /* TIMESTAMP seen on SYN packet */ |
| 78 | dsack : 1, /* D-SACK is scheduled */ |
| 79 | wscale_ok : 1, /* Wscale seen on SYN packet */ |
| 80 | sack_ok : 4, /* SACK seen on SYN packet */ |
| 81 | snd_wscale : 4, /* Window scaling received from sender */ |
| 82 | rcv_wscale : 4; /* Window scaling to send to receiver */ |
William Allen Simpson | 435cf55 | 2009-12-02 18:17:05 +0000 | [diff] [blame] | 83 | u8 cookie_plus:6, /* bytes in authenticator/cookie option */ |
| 84 | cookie_out_never:1, |
| 85 | cookie_in_always:1; |
Arnaldo Carvalho de Melo | 3a137d2 | 2006-11-28 01:12:38 -0200 | [diff] [blame] | 86 | u8 num_sacks; /* Number of SACK blocks */ |
William Allen Simpson | 435cf55 | 2009-12-02 18:17:05 +0000 | [diff] [blame] | 87 | u16 user_mss; /* mss requested by user in ioctl */ |
Arnaldo Carvalho de Melo | 3a137d2 | 2006-11-28 01:12:38 -0200 | [diff] [blame] | 88 | u16 mss_clamp; /* Maximal mss, negotiated at connection setup */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 89 | }; |
| 90 | |
William Allen Simpson | 519855c | 2009-12-02 18:14:19 +0000 | [diff] [blame] | 91 | static inline void tcp_clear_options(struct tcp_options_received *rx_opt) |
| 92 | { |
William Allen Simpson | 435cf55 | 2009-12-02 18:17:05 +0000 | [diff] [blame] | 93 | rx_opt->tstamp_ok = rx_opt->sack_ok = 0; |
| 94 | rx_opt->wscale_ok = rx_opt->snd_wscale = 0; |
| 95 | rx_opt->cookie_plus = 0; |
William Allen Simpson | 519855c | 2009-12-02 18:14:19 +0000 | [diff] [blame] | 96 | } |
| 97 | |
Adam Langley | 4389dde | 2008-07-19 00:07:02 -0700 | [diff] [blame] | 98 | /* This is the max number of SACKS that we'll generate and process. It's safe |
William Allen Simpson | 435cf55 | 2009-12-02 18:17:05 +0000 | [diff] [blame] | 99 | * to increase this, although since: |
Adam Langley | 4389dde | 2008-07-19 00:07:02 -0700 | [diff] [blame] | 100 | * size = TCPOLEN_SACK_BASE_ALIGNED (4) + n * TCPOLEN_SACK_PERBLOCK (8) |
| 101 | * only four options will fit in a standard TCP header */ |
| 102 | #define TCP_NUM_SACKS 4 |
| 103 | |
William Allen Simpson | 435cf55 | 2009-12-02 18:17:05 +0000 | [diff] [blame] | 104 | struct tcp_cookie_values; |
| 105 | struct tcp_request_sock_ops; |
| 106 | |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 107 | struct tcp_request_sock { |
YOSHIFUJI Hideaki | cfb6eeb | 2006-11-14 19:07:45 -0800 | [diff] [blame] | 108 | struct inet_request_sock req; |
| 109 | #ifdef CONFIG_TCP_MD5SIG |
| 110 | /* Only used by TCP MD5 Signature so far. */ |
Stephen Hemminger | b2e4b3d | 2009-09-01 19:25:03 +0000 | [diff] [blame] | 111 | const struct tcp_request_sock_ops *af_specific; |
YOSHIFUJI Hideaki | cfb6eeb | 2006-11-14 19:07:45 -0800 | [diff] [blame] | 112 | #endif |
Jerry Chu | 1046716 | 2012-08-31 12:29:11 +0000 | [diff] [blame] | 113 | struct sock *listener; /* needed for TFO */ |
William Allen Simpson | 435cf55 | 2009-12-02 18:17:05 +0000 | [diff] [blame] | 114 | u32 rcv_isn; |
| 115 | u32 snt_isn; |
Jerry Chu | 9ad7c04 | 2011-06-08 11:08:38 +0000 | [diff] [blame] | 116 | u32 snt_synack; /* synack sent time */ |
Jerry Chu | 1046716 | 2012-08-31 12:29:11 +0000 | [diff] [blame] | 117 | u32 rcv_nxt; /* the ack # by SYNACK. For |
| 118 | * FastOpen it's the seq# |
| 119 | * after data-in-SYN. |
| 120 | */ |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 121 | }; |
| 122 | |
Arnaldo Carvalho de Melo | 60236fd | 2005-06-18 22:47:21 -0700 | [diff] [blame] | 123 | static inline struct tcp_request_sock *tcp_rsk(const struct request_sock *req) |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 124 | { |
| 125 | return (struct tcp_request_sock *)req; |
| 126 | } |
| 127 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 128 | struct tcp_sock { |
Arnaldo Carvalho de Melo | 463c84b | 2005-08-09 20:10:42 -0700 | [diff] [blame] | 129 | /* inet_connection_sock has to be the first member of tcp_sock */ |
| 130 | struct inet_connection_sock inet_conn; |
Arnaldo Carvalho de Melo | 2ff52f2 | 2006-11-28 00:48:32 -0200 | [diff] [blame] | 131 | u16 tcp_header_len; /* Bytes of tcp header to send */ |
Ilpo Järvinen | 2a3a041 | 2009-03-14 22:45:16 +0000 | [diff] [blame] | 132 | u16 xmit_size_goal_segs; /* Goal for segmenting output packets */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 133 | |
| 134 | /* |
| 135 | * Header prediction flags |
| 136 | * 0x5?10 << 16 + snd_wnd in net byte order |
| 137 | */ |
Al Viro | dddc93c | 2006-09-27 18:32:46 -0700 | [diff] [blame] | 138 | __be32 pred_flags; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 139 | |
| 140 | /* |
| 141 | * RFC793 variables by their proper names. This means you can |
| 142 | * read the code and the spec side by side (and laugh ...) |
| 143 | * See RFC793 and RFC1122. The RFC writes these in capitals. |
| 144 | */ |
Arnaldo Carvalho de Melo | 3a137d2 | 2006-11-28 01:12:38 -0200 | [diff] [blame] | 145 | u32 rcv_nxt; /* What we want to receive next */ |
Eric Dumazet | 54287cc | 2007-02-22 03:20:44 -0800 | [diff] [blame] | 146 | u32 copied_seq; /* Head of yet unread data */ |
| 147 | u32 rcv_wup; /* rcv_nxt on last window update sent */ |
Arnaldo Carvalho de Melo | 3a137d2 | 2006-11-28 01:12:38 -0200 | [diff] [blame] | 148 | u32 snd_nxt; /* Next sequence we send */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 149 | |
Arnaldo Carvalho de Melo | 3a137d2 | 2006-11-28 01:12:38 -0200 | [diff] [blame] | 150 | u32 snd_una; /* First byte we want an ack for */ |
| 151 | u32 snd_sml; /* Last byte of the most recently transmitted small packet */ |
| 152 | u32 rcv_tstamp; /* timestamp of last received ACK (for keepalives) */ |
| 153 | u32 lsndtime; /* timestamp of last sent data packet (for restart window) */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 154 | |
Eric Dumazet | 46d3cea | 2012-07-11 05:50:31 +0000 | [diff] [blame] | 155 | struct list_head tsq_node; /* anchor in tsq_tasklet.head list */ |
| 156 | unsigned long tsq_flags; |
| 157 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 158 | /* Data for direct copy to user */ |
| 159 | struct { |
| 160 | struct sk_buff_head prequeue; |
| 161 | struct task_struct *task; |
| 162 | struct iovec *iov; |
| 163 | int memory; |
| 164 | int len; |
Chris Leech | 97fc2f0 | 2006-05-23 17:55:33 -0700 | [diff] [blame] | 165 | #ifdef CONFIG_NET_DMA |
| 166 | /* members for async copy */ |
| 167 | struct dma_chan *dma_chan; |
| 168 | int wakeup; |
| 169 | struct dma_pinned_list *pinned_list; |
| 170 | dma_cookie_t dma_cookie; |
| 171 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 172 | } ucopy; |
| 173 | |
Arnaldo Carvalho de Melo | 3a137d2 | 2006-11-28 01:12:38 -0200 | [diff] [blame] | 174 | u32 snd_wl1; /* Sequence for window update */ |
| 175 | u32 snd_wnd; /* The window we expect to receive */ |
| 176 | u32 max_window; /* Maximal window ever seen from peer */ |
| 177 | u32 mss_cache; /* Cached effective mss, not including SACKS */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 178 | |
Arnaldo Carvalho de Melo | 3a137d2 | 2006-11-28 01:12:38 -0200 | [diff] [blame] | 179 | u32 window_clamp; /* Maximal window to advertise */ |
| 180 | u32 rcv_ssthresh; /* Current window clamp */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 181 | |
Arnaldo Carvalho de Melo | 3a137d2 | 2006-11-28 01:12:38 -0200 | [diff] [blame] | 182 | u32 frto_highmark; /* snd_nxt when RTO occurred */ |
Ilpo Järvinen | b79eeeb | 2008-05-29 03:25:23 -0700 | [diff] [blame] | 183 | u16 advmss; /* Advertised MSS */ |
Arnaldo Carvalho de Melo | 3a137d2 | 2006-11-28 01:12:38 -0200 | [diff] [blame] | 184 | u8 frto_counter; /* Number of new acks after RTO */ |
Andreas Petlund | 36e31b0a | 2010-02-18 02:47:01 +0000 | [diff] [blame] | 185 | u8 nonagle : 4,/* Disable Nagle algorithm? */ |
| 186 | thin_lto : 1,/* Use linear timeouts for thin streams */ |
Andreas Petlund | 7e38017 | 2010-02-18 04:48:19 +0000 | [diff] [blame] | 187 | thin_dupack : 1,/* Fast retransmit on first dupack */ |
Pavel Emelyanov | ee99528 | 2012-04-19 03:40:39 +0000 | [diff] [blame] | 188 | repair : 1, |
| 189 | unused : 1; |
| 190 | u8 repair_queue; |
Yuchung Cheng | 750ea2b | 2012-05-02 13:30:04 +0000 | [diff] [blame] | 191 | u8 do_early_retrans:1,/* Enable RFC5827 early-retransmit */ |
Yuchung Cheng | 783237e | 2012-07-19 06:43:07 +0000 | [diff] [blame] | 192 | early_retrans_delayed:1, /* Delayed ER timer installed */ |
Yuchung Cheng | 67da22d | 2012-07-19 06:43:11 +0000 | [diff] [blame] | 193 | syn_data:1, /* SYN includes data */ |
Yuchung Cheng | 783237e | 2012-07-19 06:43:07 +0000 | [diff] [blame] | 194 | syn_fastopen:1; /* SYN includes Fast Open option */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 195 | |
| 196 | /* RTT measurement */ |
Arnaldo Carvalho de Melo | 3a137d2 | 2006-11-28 01:12:38 -0200 | [diff] [blame] | 197 | u32 srtt; /* smoothed round trip time << 3 */ |
| 198 | u32 mdev; /* medium deviation */ |
| 199 | u32 mdev_max; /* maximal mdev for the last rtt period */ |
| 200 | u32 rttvar; /* smoothed mdev_max */ |
| 201 | u32 rtt_seq; /* sequence number to update rttvar */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 202 | |
Arnaldo Carvalho de Melo | 3a137d2 | 2006-11-28 01:12:38 -0200 | [diff] [blame] | 203 | u32 packets_out; /* Packets which are "in flight" */ |
Arnaldo Carvalho de Melo | 3a137d2 | 2006-11-28 01:12:38 -0200 | [diff] [blame] | 204 | u32 retrans_out; /* Retransmitted packets out */ |
Ilpo Järvinen | b79eeeb | 2008-05-29 03:25:23 -0700 | [diff] [blame] | 205 | |
| 206 | u16 urg_data; /* Saved octet of OOB data and control flags */ |
Ilpo Järvinen | b79eeeb | 2008-05-29 03:25:23 -0700 | [diff] [blame] | 207 | u8 ecn_flags; /* ECN status bits. */ |
Ilpo Järvinen | 33f5f57 | 2008-10-07 14:43:06 -0700 | [diff] [blame] | 208 | u8 reordering; /* Packet reordering metric. */ |
| 209 | u32 snd_up; /* Urgent pointer */ |
| 210 | |
| 211 | u8 keepalive_probes; /* num of allowed keep alive probes */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 212 | /* |
| 213 | * Options received (usually on last packet, some only on SYN packets). |
| 214 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 215 | struct tcp_options_received rx_opt; |
| 216 | |
| 217 | /* |
| 218 | * Slow start and congestion control (see also Nagle, and Karn & Partridge) |
| 219 | */ |
Arnaldo Carvalho de Melo | 3a137d2 | 2006-11-28 01:12:38 -0200 | [diff] [blame] | 220 | u32 snd_ssthresh; /* Slow start size threshold */ |
| 221 | u32 snd_cwnd; /* Sending congestion window */ |
Ilpo Järvinen | f78a1b3 | 2007-10-15 12:59:43 -0700 | [diff] [blame] | 222 | u32 snd_cwnd_cnt; /* Linear increase counter */ |
David S. Miller | e0ef57c | 2007-02-22 22:52:59 -0800 | [diff] [blame] | 223 | u32 snd_cwnd_clamp; /* Do not allow snd_cwnd to grow above this */ |
Arnaldo Carvalho de Melo | 3a137d2 | 2006-11-28 01:12:38 -0200 | [diff] [blame] | 224 | u32 snd_cwnd_used; |
| 225 | u32 snd_cwnd_stamp; |
Nandita Dukkipati | a262f0c | 2011-08-21 20:21:57 +0000 | [diff] [blame] | 226 | u32 prior_cwnd; /* Congestion window at start of Recovery. */ |
| 227 | u32 prr_delivered; /* Number of newly delivered packets to |
| 228 | * receiver in Recovery. */ |
| 229 | u32 prr_out; /* Total number of pkts sent during Recovery. */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 230 | |
Arnaldo Carvalho de Melo | 3a137d2 | 2006-11-28 01:12:38 -0200 | [diff] [blame] | 231 | u32 rcv_wnd; /* Current receiver window */ |
Arnaldo Carvalho de Melo | 3a137d2 | 2006-11-28 01:12:38 -0200 | [diff] [blame] | 232 | u32 write_seq; /* Tail(+1) of data held in tcp send buffer */ |
| 233 | u32 pushed_seq; /* Last pushed seq, required to talk to windows */ |
Ilpo Järvinen | b79eeeb | 2008-05-29 03:25:23 -0700 | [diff] [blame] | 234 | u32 lost_out; /* Lost packets */ |
| 235 | u32 sacked_out; /* SACK'd packets */ |
| 236 | u32 fackets_out; /* FACK'd packets */ |
| 237 | u32 tso_deferred; |
| 238 | u32 bytes_acked; /* Appropriate Byte Counting - RFC3465 */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 239 | |
Ilpo Järvinen | b79eeeb | 2008-05-29 03:25:23 -0700 | [diff] [blame] | 240 | /* from STCP, retrans queue hinting */ |
| 241 | struct sk_buff* lost_skb_hint; |
| 242 | struct sk_buff *scoreboard_skb_hint; |
| 243 | struct sk_buff *retransmit_skb_hint; |
Ilpo Järvinen | b79eeeb | 2008-05-29 03:25:23 -0700 | [diff] [blame] | 244 | |
| 245 | struct sk_buff_head out_of_order_queue; /* Out of order segments go here */ |
| 246 | |
Kyle McMartin | c0a788c | 2012-05-07 15:33:04 -0400 | [diff] [blame] | 247 | /* SACKs data, these 2 need to be together (see tcp_options_write) */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 248 | struct tcp_sack_block duplicate_sack[1]; /* D-SACK block */ |
| 249 | struct tcp_sack_block selective_acks[4]; /* The SACKS themselves*/ |
| 250 | |
Ilpo Järvinen | fd6dad6 | 2007-11-15 19:49:47 -0800 | [diff] [blame] | 251 | struct tcp_sack_block recv_sack_cache[4]; |
Stephen Hemminger | 6a438bb | 2005-11-10 17:14:59 -0800 | [diff] [blame] | 252 | |
Neal Cardwell | ecb9719 | 2012-02-27 17:52:52 -0500 | [diff] [blame] | 253 | struct sk_buff *highest_sack; /* skb just after the highest |
| 254 | * skb with SACKed bit set |
Ilpo Järvinen | a47e5a9 | 2007-11-15 19:41:46 -0800 | [diff] [blame] | 255 | * (validity guaranteed only if |
| 256 | * sacked_out > 0) |
| 257 | */ |
Ilpo Järvinen | d738cd8 | 2007-03-24 21:03:23 -0700 | [diff] [blame] | 258 | |
Stephen Hemminger | 6a438bb | 2005-11-10 17:14:59 -0800 | [diff] [blame] | 259 | int lost_cnt_hint; |
Ilpo Järvinen | 006f582 | 2008-09-20 21:20:20 -0700 | [diff] [blame] | 260 | u32 retransmit_high; /* L-bits may be on up to this seqno */ |
Stephen Hemminger | 6a438bb | 2005-11-10 17:14:59 -0800 | [diff] [blame] | 261 | |
Ilpo Järvinen | b08d6cb | 2007-10-11 17:36:13 -0700 | [diff] [blame] | 262 | u32 lost_retrans_low; /* Sent seq after any rxmit (lowest) */ |
| 263 | |
Ilpo Järvinen | 4b749440 | 2008-05-21 17:40:05 -0700 | [diff] [blame] | 264 | u32 prior_ssthresh; /* ssthresh saved at recovery start */ |
Arnaldo Carvalho de Melo | 3a137d2 | 2006-11-28 01:12:38 -0200 | [diff] [blame] | 265 | u32 high_seq; /* snd_nxt at onset of congestion */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 266 | |
Arnaldo Carvalho de Melo | 3a137d2 | 2006-11-28 01:12:38 -0200 | [diff] [blame] | 267 | u32 retrans_stamp; /* Timestamp of the last retransmit, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 268 | * also used in SYN-SENT to remember stamp of |
| 269 | * the first SYN. */ |
Arnaldo Carvalho de Melo | 3a137d2 | 2006-11-28 01:12:38 -0200 | [diff] [blame] | 270 | u32 undo_marker; /* tracking retrans started here. */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 271 | int undo_retrans; /* number of undoable retransmissions. */ |
Arnaldo Carvalho de Melo | 3a137d2 | 2006-11-28 01:12:38 -0200 | [diff] [blame] | 272 | u32 total_retrans; /* Total retransmits for entire connection */ |
Ilpo Järvinen | b79eeeb | 2008-05-29 03:25:23 -0700 | [diff] [blame] | 273 | |
| 274 | u32 urg_seq; /* Seq of received urgent pointer */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 275 | unsigned int keepalive_time; /* time before keep alive takes place */ |
| 276 | unsigned int keepalive_intvl; /* time interval between keep alive probes */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 277 | |
Florian Westphal | a0f82f6 | 2009-04-19 09:43:48 +0000 | [diff] [blame] | 278 | int linger2; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 279 | |
| 280 | /* Receiver side RTT estimation */ |
| 281 | struct { |
Arnaldo Carvalho de Melo | 3a137d2 | 2006-11-28 01:12:38 -0200 | [diff] [blame] | 282 | u32 rtt; |
| 283 | u32 seq; |
| 284 | u32 time; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 285 | } rcv_rtt_est; |
| 286 | |
| 287 | /* Receiver queue space */ |
| 288 | struct { |
| 289 | int space; |
Arnaldo Carvalho de Melo | 3a137d2 | 2006-11-28 01:12:38 -0200 | [diff] [blame] | 290 | u32 seq; |
| 291 | u32 time; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 292 | } rcvq_space; |
John Heffner | 0e7b136 | 2006-03-20 21:32:58 -0800 | [diff] [blame] | 293 | |
| 294 | /* TCP-specific MTU probe information. */ |
| 295 | struct { |
Arnaldo Carvalho de Melo | 3a137d2 | 2006-11-28 01:12:38 -0200 | [diff] [blame] | 296 | u32 probe_seq_start; |
| 297 | u32 probe_seq_end; |
John Heffner | 0e7b136 | 2006-03-20 21:32:58 -0800 | [diff] [blame] | 298 | } mtu_probe; |
Eric Dumazet | 563d34d | 2012-07-23 09:48:52 +0200 | [diff] [blame] | 299 | u32 mtu_info; /* We received an ICMP_FRAG_NEEDED / ICMPV6_PKT_TOOBIG |
| 300 | * while socket was owned by user. |
| 301 | */ |
YOSHIFUJI Hideaki | cfb6eeb | 2006-11-14 19:07:45 -0800 | [diff] [blame] | 302 | |
| 303 | #ifdef CONFIG_TCP_MD5SIG |
| 304 | /* TCP AF-Specific parts; only used by MD5 Signature support so far */ |
Stephen Hemminger | b2e4b3d | 2009-09-01 19:25:03 +0000 | [diff] [blame] | 305 | const struct tcp_sock_af_ops *af_specific; |
YOSHIFUJI Hideaki | cfb6eeb | 2006-11-14 19:07:45 -0800 | [diff] [blame] | 306 | |
Stephen Hemminger | b2e4b3d | 2009-09-01 19:25:03 +0000 | [diff] [blame] | 307 | /* TCP MD5 Signature Option information */ |
Eric Dumazet | a8afca0 | 2012-01-31 18:45:40 +0000 | [diff] [blame] | 308 | struct tcp_md5sig_info __rcu *md5sig_info; |
YOSHIFUJI Hideaki | cfb6eeb | 2006-11-14 19:07:45 -0800 | [diff] [blame] | 309 | #endif |
William Allen Simpson | 435cf55 | 2009-12-02 18:17:05 +0000 | [diff] [blame] | 310 | |
| 311 | /* When the cookie options are generated and exchanged, then this |
| 312 | * object holds a reference to them (cookie_values->kref). Also |
| 313 | * contains related tcp_cookie_transactions fields. |
| 314 | */ |
| 315 | struct tcp_cookie_values *cookie_values; |
Jerry Chu | 1046716 | 2012-08-31 12:29:11 +0000 | [diff] [blame] | 316 | |
| 317 | /* TCP fastopen related information */ |
| 318 | struct tcp_fastopen_request *fastopen_req; |
| 319 | /* fastopen_rsk points to request_sock that resulted in this big |
| 320 | * socket. Used to retransmit SYNACKs etc. |
| 321 | */ |
| 322 | struct request_sock *fastopen_rsk; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 323 | }; |
| 324 | |
Eric Dumazet | 46d3cea | 2012-07-11 05:50:31 +0000 | [diff] [blame] | 325 | enum tsq_flags { |
| 326 | TSQ_THROTTLED, |
| 327 | TSQ_QUEUED, |
Eric Dumazet | 6f458df | 2012-07-20 05:45:50 +0000 | [diff] [blame] | 328 | TCP_TSQ_DEFERRED, /* tcp_tasklet_func() found socket was owned */ |
| 329 | TCP_WRITE_TIMER_DEFERRED, /* tcp_write_timer() found socket was owned */ |
| 330 | TCP_DELACK_TIMER_DEFERRED, /* tcp_delack_timer() found socket was owned */ |
Eric Dumazet | 563d34d | 2012-07-23 09:48:52 +0200 | [diff] [blame] | 331 | TCP_MTU_REDUCED_DEFERRED, /* tcp_v{4|6}_err() could not call |
| 332 | * tcp_v{4|6}_mtu_reduced() |
| 333 | */ |
Eric Dumazet | 46d3cea | 2012-07-11 05:50:31 +0000 | [diff] [blame] | 334 | }; |
| 335 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 336 | static inline struct tcp_sock *tcp_sk(const struct sock *sk) |
| 337 | { |
| 338 | return (struct tcp_sock *)sk; |
| 339 | } |
| 340 | |
Arnaldo Carvalho de Melo | 8feaf0c0 | 2005-08-09 20:09:30 -0700 | [diff] [blame] | 341 | struct tcp_timewait_sock { |
| 342 | struct inet_timewait_sock tw_sk; |
Arnaldo Carvalho de Melo | 3a137d2 | 2006-11-28 01:12:38 -0200 | [diff] [blame] | 343 | u32 tw_rcv_nxt; |
| 344 | u32 tw_snd_nxt; |
| 345 | u32 tw_rcv_wnd; |
| 346 | u32 tw_ts_recent; |
Arnaldo Carvalho de Melo | 8feaf0c0 | 2005-08-09 20:09:30 -0700 | [diff] [blame] | 347 | long tw_ts_recent_stamp; |
YOSHIFUJI Hideaki | cfb6eeb | 2006-11-14 19:07:45 -0800 | [diff] [blame] | 348 | #ifdef CONFIG_TCP_MD5SIG |
David S. Miller | 2397849 | 2012-06-09 14:56:12 -0700 | [diff] [blame] | 349 | struct tcp_md5sig_key *tw_md5_key; |
YOSHIFUJI Hideaki | cfb6eeb | 2006-11-14 19:07:45 -0800 | [diff] [blame] | 350 | #endif |
William Allen Simpson | 435cf55 | 2009-12-02 18:17:05 +0000 | [diff] [blame] | 351 | /* Few sockets in timewait have cookies; in that case, then this |
| 352 | * object holds a reference to them (tw_cookie_values->kref). |
| 353 | */ |
| 354 | struct tcp_cookie_values *tw_cookie_values; |
Arnaldo Carvalho de Melo | 8feaf0c0 | 2005-08-09 20:09:30 -0700 | [diff] [blame] | 355 | }; |
| 356 | |
| 357 | static inline struct tcp_timewait_sock *tcp_twsk(const struct sock *sk) |
| 358 | { |
| 359 | return (struct tcp_timewait_sock *)sk; |
| 360 | } |
| 361 | |
Jerry Chu | 1046716 | 2012-08-31 12:29:11 +0000 | [diff] [blame] | 362 | static inline bool tcp_passive_fastopen(const struct sock *sk) |
| 363 | { |
| 364 | return (sk->sk_state == TCP_SYN_RECV && |
| 365 | tcp_sk(sk)->fastopen_rsk != NULL); |
| 366 | } |
| 367 | |
| 368 | static inline bool fastopen_cookie_present(struct tcp_fastopen_cookie *foc) |
| 369 | { |
| 370 | return foc->len != -1; |
| 371 | } |
| 372 | |
Christoph Paasch | bb68b64 | 2012-09-18 14:19:23 +0000 | [diff] [blame] | 373 | extern void tcp_sock_destruct(struct sock *sk); |
| 374 | |
Jerry Chu | 1046716 | 2012-08-31 12:29:11 +0000 | [diff] [blame] | 375 | static inline int fastopen_init_queue(struct sock *sk, int backlog) |
| 376 | { |
| 377 | struct request_sock_queue *queue = |
| 378 | &inet_csk(sk)->icsk_accept_queue; |
| 379 | |
| 380 | if (queue->fastopenq == NULL) { |
| 381 | queue->fastopenq = kzalloc( |
| 382 | sizeof(struct fastopen_queue), |
| 383 | sk->sk_allocation); |
| 384 | if (queue->fastopenq == NULL) |
| 385 | return -ENOMEM; |
Christoph Paasch | bb68b64 | 2012-09-18 14:19:23 +0000 | [diff] [blame] | 386 | |
| 387 | sk->sk_destruct = tcp_sock_destruct; |
Jerry Chu | 1046716 | 2012-08-31 12:29:11 +0000 | [diff] [blame] | 388 | spin_lock_init(&queue->fastopenq->lock); |
| 389 | } |
| 390 | queue->fastopenq->max_qlen = backlog; |
| 391 | return 0; |
| 392 | } |
| 393 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 394 | #endif /* _LINUX_TCP_H */ |