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 module. |
| 7 | * |
| 8 | * Version: @(#)tcp.h 1.0.5 05/23/93 |
| 9 | * |
Jesper Juhl | 02c30a8 | 2005-05-05 16:16:16 -0700 | [diff] [blame] | 10 | * Authors: Ross Biro |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 11 | * 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 _TCP_H |
| 19 | #define _TCP_H |
| 20 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 21 | #define FASTRETRANS_DEBUG 1 |
| 22 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 23 | #include <linux/list.h> |
| 24 | #include <linux/tcp.h> |
Paul Gortmaker | 187f188 | 2011-11-23 20:12:59 -0500 | [diff] [blame] | 25 | #include <linux/bug.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 26 | #include <linux/slab.h> |
| 27 | #include <linux/cache.h> |
| 28 | #include <linux/percpu.h> |
Herbert Xu | fb286bb | 2005-11-10 13:01:24 -0800 | [diff] [blame] | 29 | #include <linux/skbuff.h> |
Chris Leech | 97fc2f0 | 2006-05-23 17:55:33 -0700 | [diff] [blame] | 30 | #include <linux/dmaengine.h> |
YOSHIFUJI Hideaki | cfb6eeb | 2006-11-14 19:07:45 -0800 | [diff] [blame] | 31 | #include <linux/crypto.h> |
Glenn Griffin | c6aefaf | 2008-02-07 21:49:26 -0800 | [diff] [blame] | 32 | #include <linux/cryptohash.h> |
William Allen Simpson | 435cf55 | 2009-12-02 18:17:05 +0000 | [diff] [blame] | 33 | #include <linux/kref.h> |
Arnaldo Carvalho de Melo | 3f421ba | 2005-08-09 20:11:08 -0700 | [diff] [blame] | 34 | |
| 35 | #include <net/inet_connection_sock.h> |
Arnaldo Carvalho de Melo | 295ff7e | 2005-08-09 20:44:40 -0700 | [diff] [blame] | 36 | #include <net/inet_timewait_sock.h> |
Arnaldo Carvalho de Melo | 77d8bf9 | 2005-08-09 20:00:51 -0700 | [diff] [blame] | 37 | #include <net/inet_hashtables.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 38 | #include <net/checksum.h> |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 39 | #include <net/request_sock.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 40 | #include <net/sock.h> |
| 41 | #include <net/snmp.h> |
| 42 | #include <net/ip.h> |
Arnaldo Carvalho de Melo | c752f07 | 2005-08-09 20:08:28 -0700 | [diff] [blame] | 43 | #include <net/tcp_states.h> |
Ilpo Järvinen | bdf1ee5 | 2007-05-27 02:04:16 -0700 | [diff] [blame] | 44 | #include <net/inet_ecn.h> |
Satoru SATOH | 0c26689 | 2009-05-04 11:11:01 -0700 | [diff] [blame] | 45 | #include <net/dst.h> |
Arnaldo Carvalho de Melo | c752f07 | 2005-08-09 20:08:28 -0700 | [diff] [blame] | 46 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 47 | #include <linux/seq_file.h> |
Glauber Costa | 180d8cd | 2011-12-11 21:47:02 +0000 | [diff] [blame] | 48 | #include <linux/memcontrol.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 49 | |
Arnaldo Carvalho de Melo | 6e04e02 | 2005-08-09 20:07:35 -0700 | [diff] [blame] | 50 | extern struct inet_hashinfo tcp_hashinfo; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 51 | |
Eric Dumazet | dd24c00 | 2008-11-25 21:17:14 -0800 | [diff] [blame] | 52 | extern struct percpu_counter tcp_orphan_count; |
Joe Perches | 5c9f302 | 2013-09-23 11:33:32 -0700 | [diff] [blame] | 53 | void tcp_time_wait(struct sock *sk, int state, int timeo); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 54 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 55 | #define MAX_TCP_HEADER (128 + MAX_HEADER) |
Adam Langley | 33ad798 | 2008-07-19 00:04:31 -0700 | [diff] [blame] | 56 | #define MAX_TCP_OPTION_SPACE 40 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 57 | |
| 58 | /* |
| 59 | * Never offer a window over 32767 without using window scaling. Some |
| 60 | * poor stacks do signed 16bit maths! |
| 61 | */ |
| 62 | #define MAX_TCP_WINDOW 32767U |
| 63 | |
| 64 | /* Minimal accepted MSS. It is (60+60+8) - (20+20). */ |
| 65 | #define TCP_MIN_MSS 88U |
| 66 | |
John Heffner | 5d424d5 | 2006-03-20 17:53:41 -0800 | [diff] [blame] | 67 | /* The least MTU to use for probing */ |
| 68 | #define TCP_BASE_MSS 512 |
| 69 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 70 | /* After receiving this amount of duplicate ACKs fast retransmit starts. */ |
| 71 | #define TCP_FASTRETRANS_THRESH 3 |
| 72 | |
| 73 | /* Maximal reordering. */ |
| 74 | #define TCP_MAX_REORDERING 127 |
| 75 | |
| 76 | /* Maximal number of ACKs sent quickly to accelerate slow-start. */ |
| 77 | #define TCP_MAX_QUICKACKS 16U |
| 78 | |
| 79 | /* urg_data states */ |
| 80 | #define TCP_URG_VALID 0x0100 |
| 81 | #define TCP_URG_NOTYET 0x0200 |
| 82 | #define TCP_URG_READ 0x0400 |
| 83 | |
| 84 | #define TCP_RETR1 3 /* |
| 85 | * This is how many retries it does before it |
| 86 | * tries to figure out if the gateway is |
| 87 | * down. Minimal RFC value is 3; it corresponds |
| 88 | * to ~3sec-8min depending on RTO. |
| 89 | */ |
| 90 | |
| 91 | #define TCP_RETR2 15 /* |
| 92 | * This should take at least |
| 93 | * 90 minutes to time out. |
| 94 | * RFC1122 says that the limit is 100 sec. |
| 95 | * 15 is ~13-30min depending on RTO. |
| 96 | */ |
| 97 | |
Alex Bergmann | 6c9ff97 | 2012-08-31 02:48:31 +0000 | [diff] [blame] | 98 | #define TCP_SYN_RETRIES 6 /* This is how many retries are done |
| 99 | * when active opening a connection. |
| 100 | * RFC1122 says the minimum retry MUST |
| 101 | * be at least 180secs. Nevertheless |
| 102 | * this value is corresponding to |
| 103 | * 63secs of retransmission with the |
| 104 | * current initial RTO. |
| 105 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 106 | |
Alex Bergmann | 6c9ff97 | 2012-08-31 02:48:31 +0000 | [diff] [blame] | 107 | #define TCP_SYNACK_RETRIES 5 /* This is how may retries are done |
| 108 | * when passive opening a connection. |
| 109 | * This is corresponding to 31secs of |
| 110 | * retransmission with the current |
| 111 | * initial RTO. |
| 112 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 113 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 114 | #define TCP_TIMEWAIT_LEN (60*HZ) /* how long to wait to destroy TIME-WAIT |
| 115 | * state, about 60 seconds */ |
| 116 | #define TCP_FIN_TIMEOUT TCP_TIMEWAIT_LEN |
| 117 | /* BSD style FIN_WAIT2 deadlock breaker. |
| 118 | * It used to be 3min, new value is 60sec, |
| 119 | * to combine FIN-WAIT-2 timeout with |
| 120 | * TIME-WAIT timer. |
| 121 | */ |
| 122 | |
| 123 | #define TCP_DELACK_MAX ((unsigned)(HZ/5)) /* maximal time to delay before sending an ACK */ |
| 124 | #if HZ >= 100 |
| 125 | #define TCP_DELACK_MIN ((unsigned)(HZ/25)) /* minimal time to delay before sending an ACK */ |
| 126 | #define TCP_ATO_MIN ((unsigned)(HZ/25)) |
| 127 | #else |
| 128 | #define TCP_DELACK_MIN 4U |
| 129 | #define TCP_ATO_MIN 4U |
| 130 | #endif |
| 131 | #define TCP_RTO_MAX ((unsigned)(120*HZ)) |
| 132 | #define TCP_RTO_MIN ((unsigned)(HZ/5)) |
Eric Dumazet | fd4f2ce | 2012-04-12 19:48:40 +0000 | [diff] [blame] | 133 | #define TCP_TIMEOUT_INIT ((unsigned)(1*HZ)) /* RFC6298 2.1 initial RTO value */ |
Jerry Chu | 9ad7c04 | 2011-06-08 11:08:38 +0000 | [diff] [blame] | 134 | #define TCP_TIMEOUT_FALLBACK ((unsigned)(3*HZ)) /* RFC 1122 initial RTO value, now |
| 135 | * used as a fallback RTO for the |
| 136 | * initial data transmission if no |
| 137 | * valid RTT sample has been acquired, |
| 138 | * most likely due to retrans in 3WHS. |
| 139 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 140 | |
| 141 | #define TCP_RESOURCE_PROBE_INTERVAL ((unsigned)(HZ/2U)) /* Maximal interval between probes |
| 142 | * for local resources. |
| 143 | */ |
| 144 | |
| 145 | #define TCP_KEEPALIVE_TIME (120*60*HZ) /* two hours */ |
| 146 | #define TCP_KEEPALIVE_PROBES 9 /* Max of 9 keepalive probes */ |
| 147 | #define TCP_KEEPALIVE_INTVL (75*HZ) |
| 148 | |
| 149 | #define MAX_TCP_KEEPIDLE 32767 |
| 150 | #define MAX_TCP_KEEPINTVL 32767 |
| 151 | #define MAX_TCP_KEEPCNT 127 |
| 152 | #define MAX_TCP_SYNCNT 127 |
| 153 | |
| 154 | #define TCP_SYNQ_INTERVAL (HZ/5) /* Period of SYNACK timer */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 155 | |
| 156 | #define TCP_PAWS_24DAYS (60 * 60 * 24 * 24) |
| 157 | #define TCP_PAWS_MSL 60 /* Per-host timestamps are invalidated |
| 158 | * after this time. It should be equal |
| 159 | * (or greater than) TCP_TIMEWAIT_LEN |
| 160 | * to provide reliability equal to one |
| 161 | * provided by timewait state. |
| 162 | */ |
| 163 | #define TCP_PAWS_WINDOW 1 /* Replay window for per-host |
| 164 | * timestamps. It must be less than |
| 165 | * minimal timewait lifetime. |
| 166 | */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 167 | /* |
| 168 | * TCP option |
| 169 | */ |
| 170 | |
| 171 | #define TCPOPT_NOP 1 /* Padding */ |
| 172 | #define TCPOPT_EOL 0 /* End of options */ |
| 173 | #define TCPOPT_MSS 2 /* Segment size negotiating */ |
| 174 | #define TCPOPT_WINDOW 3 /* Window scaling */ |
| 175 | #define TCPOPT_SACK_PERM 4 /* SACK Permitted */ |
| 176 | #define TCPOPT_SACK 5 /* SACK Block */ |
| 177 | #define TCPOPT_TIMESTAMP 8 /* Better RTT estimations/PAWS */ |
YOSHIFUJI Hideaki | cfb6eeb | 2006-11-14 19:07:45 -0800 | [diff] [blame] | 178 | #define TCPOPT_MD5SIG 19 /* MD5 Signature (RFC2385) */ |
Yuchung Cheng | 2100c8d | 2012-07-19 06:43:05 +0000 | [diff] [blame] | 179 | #define TCPOPT_EXP 254 /* Experimental */ |
| 180 | /* Magic number to be after the option value for sharing TCP |
| 181 | * experimental options. See draft-ietf-tcpm-experimental-options-00.txt |
| 182 | */ |
| 183 | #define TCPOPT_FASTOPEN_MAGIC 0xF989 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 184 | |
| 185 | /* |
| 186 | * TCP option lengths |
| 187 | */ |
| 188 | |
| 189 | #define TCPOLEN_MSS 4 |
| 190 | #define TCPOLEN_WINDOW 3 |
| 191 | #define TCPOLEN_SACK_PERM 2 |
| 192 | #define TCPOLEN_TIMESTAMP 10 |
YOSHIFUJI Hideaki | cfb6eeb | 2006-11-14 19:07:45 -0800 | [diff] [blame] | 193 | #define TCPOLEN_MD5SIG 18 |
Yuchung Cheng | 2100c8d | 2012-07-19 06:43:05 +0000 | [diff] [blame] | 194 | #define TCPOLEN_EXP_FASTOPEN_BASE 4 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 195 | |
| 196 | /* But this is what stacks really send out. */ |
| 197 | #define TCPOLEN_TSTAMP_ALIGNED 12 |
| 198 | #define TCPOLEN_WSCALE_ALIGNED 4 |
| 199 | #define TCPOLEN_SACKPERM_ALIGNED 4 |
| 200 | #define TCPOLEN_SACK_BASE 2 |
| 201 | #define TCPOLEN_SACK_BASE_ALIGNED 4 |
| 202 | #define TCPOLEN_SACK_PERBLOCK 8 |
YOSHIFUJI Hideaki | cfb6eeb | 2006-11-14 19:07:45 -0800 | [diff] [blame] | 203 | #define TCPOLEN_MD5SIG_ALIGNED 20 |
Adam Langley | 33ad798 | 2008-07-19 00:04:31 -0700 | [diff] [blame] | 204 | #define TCPOLEN_MSS_ALIGNED 4 |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 205 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 206 | /* Flags in tp->nonagle */ |
| 207 | #define TCP_NAGLE_OFF 1 /* Nagle's algo is disabled */ |
| 208 | #define TCP_NAGLE_CORK 2 /* Socket is corked */ |
Stephen Hemminger | caa20d9a | 2005-11-10 17:13:47 -0800 | [diff] [blame] | 209 | #define TCP_NAGLE_PUSH 4 /* Cork is overridden for already queued data */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 210 | |
Andreas Petlund | 36e31b0a | 2010-02-18 02:47:01 +0000 | [diff] [blame] | 211 | /* TCP thin-stream limits */ |
| 212 | #define TCP_THIN_LINEAR_RETRIES 6 /* After 6 linear retries, do exp. backoff */ |
| 213 | |
David S. Miller | 7eb3852 | 2011-02-05 18:13:45 -0800 | [diff] [blame] | 214 | /* TCP initial congestion window as per draft-hkchu-tcpm-initcwnd-01 */ |
David S. Miller | 442b963 | 2011-02-02 17:05:11 -0800 | [diff] [blame] | 215 | #define TCP_INIT_CWND 10 |
| 216 | |
Yuchung Cheng | cf60af0 | 2012-07-19 06:43:09 +0000 | [diff] [blame] | 217 | /* Bit Flags for sysctl_tcp_fastopen */ |
| 218 | #define TFO_CLIENT_ENABLE 1 |
Jerry Chu | 1046716 | 2012-08-31 12:29:11 +0000 | [diff] [blame] | 219 | #define TFO_SERVER_ENABLE 2 |
Yuchung Cheng | 67da22d | 2012-07-19 06:43:11 +0000 | [diff] [blame] | 220 | #define TFO_CLIENT_NO_COOKIE 4 /* Data in SYN w/o cookie option */ |
Yuchung Cheng | cf60af0 | 2012-07-19 06:43:09 +0000 | [diff] [blame] | 221 | |
Jerry Chu | 1046716 | 2012-08-31 12:29:11 +0000 | [diff] [blame] | 222 | /* Process SYN data but skip cookie validation */ |
| 223 | #define TFO_SERVER_COOKIE_NOT_CHKED 0x100 |
| 224 | /* Accept SYN data w/o any cookie option */ |
| 225 | #define TFO_SERVER_COOKIE_NOT_REQD 0x200 |
| 226 | |
| 227 | /* Force enable TFO on all listeners, i.e., not requiring the |
| 228 | * TCP_FASTOPEN socket option. SOCKOPT1/2 determine how to set max_qlen. |
| 229 | */ |
| 230 | #define TFO_SERVER_WO_SOCKOPT1 0x400 |
| 231 | #define TFO_SERVER_WO_SOCKOPT2 0x800 |
| 232 | /* Always create TFO child sockets on a TFO listener even when |
| 233 | * cookie/data not present. (For testing purpose!) |
| 234 | */ |
| 235 | #define TFO_SERVER_ALWAYS 0x1000 |
| 236 | |
Arnaldo Carvalho de Melo | 295ff7e | 2005-08-09 20:44:40 -0700 | [diff] [blame] | 237 | extern struct inet_timewait_death_row tcp_death_row; |
| 238 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 239 | /* sysctl variables for tcp */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 240 | extern int sysctl_tcp_timestamps; |
| 241 | extern int sysctl_tcp_window_scaling; |
| 242 | extern int sysctl_tcp_sack; |
| 243 | extern int sysctl_tcp_fin_timeout; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 244 | extern int sysctl_tcp_keepalive_time; |
| 245 | extern int sysctl_tcp_keepalive_probes; |
| 246 | extern int sysctl_tcp_keepalive_intvl; |
| 247 | extern int sysctl_tcp_syn_retries; |
| 248 | extern int sysctl_tcp_synack_retries; |
| 249 | extern int sysctl_tcp_retries1; |
| 250 | extern int sysctl_tcp_retries2; |
| 251 | extern int sysctl_tcp_orphan_retries; |
| 252 | extern int sysctl_tcp_syncookies; |
Yuchung Cheng | 2100c8d | 2012-07-19 06:43:05 +0000 | [diff] [blame] | 253 | extern int sysctl_tcp_fastopen; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 254 | extern int sysctl_tcp_retrans_collapse; |
| 255 | extern int sysctl_tcp_stdurg; |
| 256 | extern int sysctl_tcp_rfc1337; |
| 257 | extern int sysctl_tcp_abort_on_overflow; |
| 258 | extern int sysctl_tcp_max_orphans; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 259 | extern int sysctl_tcp_fack; |
| 260 | extern int sysctl_tcp_reordering; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 261 | extern int sysctl_tcp_dsack; |
Eric W. Biederman | a4fe34b | 2013-10-19 16:25:36 -0700 | [diff] [blame] | 262 | extern long sysctl_tcp_mem[3]; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 263 | extern int sysctl_tcp_wmem[3]; |
| 264 | extern int sysctl_tcp_rmem[3]; |
| 265 | extern int sysctl_tcp_app_win; |
| 266 | extern int sysctl_tcp_adv_win_scale; |
| 267 | extern int sysctl_tcp_tw_reuse; |
| 268 | extern int sysctl_tcp_frto; |
| 269 | extern int sysctl_tcp_low_latency; |
Chris Leech | 9593782 | 2006-05-23 18:02:55 -0700 | [diff] [blame] | 270 | extern int sysctl_tcp_dma_copybreak; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 271 | extern int sysctl_tcp_nometrics_save; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 272 | extern int sysctl_tcp_moderate_rcvbuf; |
| 273 | extern int sysctl_tcp_tso_win_divisor; |
John Heffner | 5d424d5 | 2006-03-20 17:53:41 -0800 | [diff] [blame] | 274 | extern int sysctl_tcp_mtu_probing; |
| 275 | extern int sysctl_tcp_base_mss; |
Rick Jones | 15d99e0 | 2006-03-20 22:40:29 -0800 | [diff] [blame] | 276 | extern int sysctl_tcp_workaround_signed_windows; |
David S. Miller | 35089bb | 2006-06-13 22:33:04 -0700 | [diff] [blame] | 277 | extern int sysctl_tcp_slow_start_after_idle; |
Andreas Petlund | 36e31b0a | 2010-02-18 02:47:01 +0000 | [diff] [blame] | 278 | extern int sysctl_tcp_thin_linear_timeouts; |
Andreas Petlund | 7e38017 | 2010-02-18 04:48:19 +0000 | [diff] [blame] | 279 | extern int sysctl_tcp_thin_dupack; |
Yuchung Cheng | eed530b | 2012-05-02 13:30:03 +0000 | [diff] [blame] | 280 | extern int sysctl_tcp_early_retrans; |
Eric Dumazet | 46d3cea | 2012-07-11 05:50:31 +0000 | [diff] [blame] | 281 | extern int sysctl_tcp_limit_output_bytes; |
Eric Dumazet | 282f23c | 2012-07-17 10:13:05 +0200 | [diff] [blame] | 282 | extern int sysctl_tcp_challenge_ack_limit; |
Eric Dumazet | c9bee3b7 | 2013-07-22 20:27:07 -0700 | [diff] [blame] | 283 | extern unsigned int sysctl_tcp_notsent_lowat; |
Eric Dumazet | 95bd09e | 2013-08-27 05:46:32 -0700 | [diff] [blame] | 284 | extern int sysctl_tcp_min_tso_segs; |
Eric Dumazet | f54b311 | 2013-12-05 22:36:05 -0800 | [diff] [blame] | 285 | extern int sysctl_tcp_autocorking; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 286 | |
Eric Dumazet | 8d987e5 | 2010-11-09 23:24:26 +0000 | [diff] [blame] | 287 | extern atomic_long_t tcp_memory_allocated; |
Eric Dumazet | 1748376 | 2008-11-25 21:16:35 -0800 | [diff] [blame] | 288 | extern struct percpu_counter tcp_sockets_allocated; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 289 | extern int tcp_memory_pressure; |
| 290 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 291 | /* |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 292 | * The next routines deal with comparing 32 bit unsigned ints |
| 293 | * and worry about wraparound (automatic with unsigned arithmetic). |
| 294 | */ |
| 295 | |
Eric Dumazet | a2a385d | 2012-05-16 23:15:34 +0000 | [diff] [blame] | 296 | static inline bool before(__u32 seq1, __u32 seq2) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 297 | { |
Gerrit Renker | 0d630cc | 2007-01-04 12:25:16 -0800 | [diff] [blame] | 298 | return (__s32)(seq1-seq2) < 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 299 | } |
Gerrit Renker | 9a036b9c | 2006-12-20 10:25:55 -0800 | [diff] [blame] | 300 | #define after(seq2, seq1) before(seq1, seq2) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 301 | |
| 302 | /* is s2<=s1<=s3 ? */ |
Eric Dumazet | a2a385d | 2012-05-16 23:15:34 +0000 | [diff] [blame] | 303 | static inline bool between(__u32 seq1, __u32 seq2, __u32 seq3) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 304 | { |
| 305 | return seq3 - seq2 >= seq1 - seq2; |
| 306 | } |
| 307 | |
Arun Sharma | efcdbf2 | 2012-01-30 14:16:06 -0800 | [diff] [blame] | 308 | static inline bool tcp_out_of_memory(struct sock *sk) |
| 309 | { |
| 310 | if (sk->sk_wmem_queued > SOCK_MIN_SNDBUF && |
| 311 | sk_memory_allocated(sk) > sk_prot_mem_limits(sk, 2)) |
| 312 | return true; |
| 313 | return false; |
| 314 | } |
| 315 | |
David S. Miller | ad1af0f | 2010-08-25 02:27:49 -0700 | [diff] [blame] | 316 | static inline bool tcp_too_many_orphans(struct sock *sk, int shift) |
Pavel Emelianov | e4fd5da | 2007-05-29 13:19:18 -0700 | [diff] [blame] | 317 | { |
David S. Miller | ad1af0f | 2010-08-25 02:27:49 -0700 | [diff] [blame] | 318 | struct percpu_counter *ocp = sk->sk_prot->orphan_count; |
| 319 | int orphans = percpu_counter_read_positive(ocp); |
| 320 | |
| 321 | if (orphans << shift > sysctl_tcp_max_orphans) { |
| 322 | orphans = percpu_counter_sum_positive(ocp); |
| 323 | if (orphans << shift > sysctl_tcp_max_orphans) |
| 324 | return true; |
| 325 | } |
David S. Miller | ad1af0f | 2010-08-25 02:27:49 -0700 | [diff] [blame] | 326 | return false; |
Pavel Emelianov | e4fd5da | 2007-05-29 13:19:18 -0700 | [diff] [blame] | 327 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 328 | |
Joe Perches | 5c9f302 | 2013-09-23 11:33:32 -0700 | [diff] [blame] | 329 | bool tcp_check_oom(struct sock *sk, int shift); |
Arun Sharma | efcdbf2 | 2012-01-30 14:16:06 -0800 | [diff] [blame] | 330 | |
Florian Westphal | a0f82f6 | 2009-04-19 09:43:48 +0000 | [diff] [blame] | 331 | /* syncookies: remember time of last synqueue overflow */ |
| 332 | static inline void tcp_synq_overflow(struct sock *sk) |
| 333 | { |
| 334 | tcp_sk(sk)->rx_opt.ts_recent_stamp = jiffies; |
| 335 | } |
| 336 | |
| 337 | /* syncookies: no recent synqueue overflow on this listening socket? */ |
Eric Dumazet | a2a385d | 2012-05-16 23:15:34 +0000 | [diff] [blame] | 338 | static inline bool tcp_synq_no_recent_overflow(const struct sock *sk) |
Florian Westphal | a0f82f6 | 2009-04-19 09:43:48 +0000 | [diff] [blame] | 339 | { |
| 340 | unsigned long last_overflow = tcp_sk(sk)->rx_opt.ts_recent_stamp; |
Jerry Chu | 9ad7c04 | 2011-06-08 11:08:38 +0000 | [diff] [blame] | 341 | return time_after(jiffies, last_overflow + TCP_TIMEOUT_FALLBACK); |
Florian Westphal | a0f82f6 | 2009-04-19 09:43:48 +0000 | [diff] [blame] | 342 | } |
| 343 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 344 | extern struct proto tcp_prot; |
| 345 | |
Pavel Emelyanov | 57ef42d | 2008-07-18 04:02:08 -0700 | [diff] [blame] | 346 | #define TCP_INC_STATS(net, field) SNMP_INC_STATS((net)->mib.tcp_statistics, field) |
| 347 | #define TCP_INC_STATS_BH(net, field) SNMP_INC_STATS_BH((net)->mib.tcp_statistics, field) |
| 348 | #define TCP_DEC_STATS(net, field) SNMP_DEC_STATS((net)->mib.tcp_statistics, field) |
| 349 | #define TCP_ADD_STATS_USER(net, field, val) SNMP_ADD_STATS_USER((net)->mib.tcp_statistics, field, val) |
Tom Herbert | aa2ea05 | 2010-04-22 07:00:24 +0000 | [diff] [blame] | 350 | #define TCP_ADD_STATS(net, field, val) SNMP_ADD_STATS((net)->mib.tcp_statistics, field, val) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 351 | |
Joe Perches | 5c9f302 | 2013-09-23 11:33:32 -0700 | [diff] [blame] | 352 | void tcp_tasklet_init(void); |
Eric Dumazet | 46d3cea | 2012-07-11 05:50:31 +0000 | [diff] [blame] | 353 | |
Joe Perches | 5c9f302 | 2013-09-23 11:33:32 -0700 | [diff] [blame] | 354 | void tcp_v4_err(struct sk_buff *skb, u32); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 355 | |
Joe Perches | 5c9f302 | 2013-09-23 11:33:32 -0700 | [diff] [blame] | 356 | void tcp_shutdown(struct sock *sk, int how); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 357 | |
Joe Perches | 5c9f302 | 2013-09-23 11:33:32 -0700 | [diff] [blame] | 358 | void tcp_v4_early_demux(struct sk_buff *skb); |
| 359 | int tcp_v4_rcv(struct sk_buff *skb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 360 | |
Joe Perches | 5c9f302 | 2013-09-23 11:33:32 -0700 | [diff] [blame] | 361 | int tcp_v4_tw_remember_stamp(struct inet_timewait_sock *tw); |
| 362 | int tcp_sendmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, |
| 363 | size_t size); |
| 364 | int tcp_sendpage(struct sock *sk, struct page *page, int offset, size_t size, |
| 365 | int flags); |
| 366 | void tcp_release_cb(struct sock *sk); |
| 367 | void tcp_wfree(struct sk_buff *skb); |
| 368 | void tcp_write_timer_handler(struct sock *sk); |
| 369 | void tcp_delack_timer_handler(struct sock *sk); |
| 370 | int tcp_ioctl(struct sock *sk, int cmd, unsigned long arg); |
| 371 | int tcp_rcv_state_process(struct sock *sk, struct sk_buff *skb, |
| 372 | const struct tcphdr *th, unsigned int len); |
| 373 | void tcp_rcv_established(struct sock *sk, struct sk_buff *skb, |
| 374 | const struct tcphdr *th, unsigned int len); |
| 375 | void tcp_rcv_space_adjust(struct sock *sk); |
| 376 | void tcp_cleanup_rbuf(struct sock *sk, int copied); |
| 377 | int tcp_twsk_unique(struct sock *sk, struct sock *sktw, void *twp); |
| 378 | void tcp_twsk_destructor(struct sock *sk); |
| 379 | ssize_t tcp_splice_read(struct socket *sk, loff_t *ppos, |
| 380 | struct pipe_inode_info *pipe, size_t len, |
| 381 | unsigned int flags); |
Jens Axboe | 9c55e01 | 2007-11-06 23:30:13 -0800 | [diff] [blame] | 382 | |
Arnaldo Carvalho de Melo | 463c84b | 2005-08-09 20:10:42 -0700 | [diff] [blame] | 383 | static inline void tcp_dec_quickack_mode(struct sock *sk, |
| 384 | const unsigned int pkts) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 385 | { |
Arnaldo Carvalho de Melo | 463c84b | 2005-08-09 20:10:42 -0700 | [diff] [blame] | 386 | struct inet_connection_sock *icsk = inet_csk(sk); |
David S. Miller | fc6415bc | 2005-07-05 15:17:45 -0700 | [diff] [blame] | 387 | |
Arnaldo Carvalho de Melo | 463c84b | 2005-08-09 20:10:42 -0700 | [diff] [blame] | 388 | if (icsk->icsk_ack.quick) { |
| 389 | if (pkts >= icsk->icsk_ack.quick) { |
| 390 | icsk->icsk_ack.quick = 0; |
David S. Miller | fc6415bc | 2005-07-05 15:17:45 -0700 | [diff] [blame] | 391 | /* Leaving quickack mode we deflate ATO. */ |
Arnaldo Carvalho de Melo | 463c84b | 2005-08-09 20:10:42 -0700 | [diff] [blame] | 392 | icsk->icsk_ack.ato = TCP_ATO_MIN; |
David S. Miller | fc6415bc | 2005-07-05 15:17:45 -0700 | [diff] [blame] | 393 | } else |
Arnaldo Carvalho de Melo | 463c84b | 2005-08-09 20:10:42 -0700 | [diff] [blame] | 394 | icsk->icsk_ack.quick -= pkts; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 395 | } |
| 396 | } |
| 397 | |
Ilpo Järvinen | bdf1ee5 | 2007-05-27 02:04:16 -0700 | [diff] [blame] | 398 | #define TCP_ECN_OK 1 |
| 399 | #define TCP_ECN_QUEUE_CWR 2 |
| 400 | #define TCP_ECN_DEMAND_CWR 4 |
Eric Dumazet | 7a269ff | 2011-09-22 20:02:19 +0000 | [diff] [blame] | 401 | #define TCP_ECN_SEEN 8 |
Ilpo Järvinen | bdf1ee5 | 2007-05-27 02:04:16 -0700 | [diff] [blame] | 402 | |
Eric Dumazet | fd2c3ef | 2009-11-03 03:26:03 +0000 | [diff] [blame] | 403 | enum tcp_tw_status { |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 404 | TCP_TW_SUCCESS = 0, |
| 405 | TCP_TW_RST = 1, |
| 406 | TCP_TW_ACK = 2, |
| 407 | TCP_TW_SYN = 3 |
| 408 | }; |
| 409 | |
| 410 | |
Joe Perches | 5c9f302 | 2013-09-23 11:33:32 -0700 | [diff] [blame] | 411 | enum tcp_tw_status tcp_timewait_state_process(struct inet_timewait_sock *tw, |
| 412 | struct sk_buff *skb, |
| 413 | const struct tcphdr *th); |
| 414 | struct sock *tcp_check_req(struct sock *sk, struct sk_buff *skb, |
| 415 | struct request_sock *req, struct request_sock **prev, |
| 416 | bool fastopen); |
| 417 | int tcp_child_process(struct sock *parent, struct sock *child, |
| 418 | struct sk_buff *skb); |
| 419 | void tcp_enter_loss(struct sock *sk, int how); |
| 420 | void tcp_clear_retrans(struct tcp_sock *tp); |
| 421 | void tcp_update_metrics(struct sock *sk); |
| 422 | void tcp_init_metrics(struct sock *sk); |
| 423 | void tcp_metrics_init(void); |
| 424 | bool tcp_peer_is_proven(struct request_sock *req, struct dst_entry *dst, |
| 425 | bool paws_check); |
| 426 | bool tcp_remember_stamp(struct sock *sk); |
| 427 | bool tcp_tw_remember_stamp(struct inet_timewait_sock *tw); |
| 428 | void tcp_fetch_timewait_stamp(struct sock *sk, struct dst_entry *dst); |
| 429 | void tcp_disable_fack(struct tcp_sock *tp); |
| 430 | void tcp_close(struct sock *sk, long timeout); |
| 431 | void tcp_init_sock(struct sock *sk); |
| 432 | unsigned int tcp_poll(struct file *file, struct socket *sock, |
| 433 | struct poll_table_struct *wait); |
| 434 | int tcp_getsockopt(struct sock *sk, int level, int optname, |
| 435 | char __user *optval, int __user *optlen); |
| 436 | int tcp_setsockopt(struct sock *sk, int level, int optname, |
| 437 | char __user *optval, unsigned int optlen); |
| 438 | int compat_tcp_getsockopt(struct sock *sk, int level, int optname, |
Changli Gao | 53d3176 | 2010-07-10 20:41:06 +0000 | [diff] [blame] | 439 | char __user *optval, int __user *optlen); |
Joe Perches | 5c9f302 | 2013-09-23 11:33:32 -0700 | [diff] [blame] | 440 | int compat_tcp_setsockopt(struct sock *sk, int level, int optname, |
Changli Gao | 53d3176 | 2010-07-10 20:41:06 +0000 | [diff] [blame] | 441 | char __user *optval, unsigned int optlen); |
Joe Perches | 5c9f302 | 2013-09-23 11:33:32 -0700 | [diff] [blame] | 442 | void tcp_set_keepalive(struct sock *sk, int val); |
| 443 | void tcp_syn_ack_timeout(struct sock *sk, struct request_sock *req); |
| 444 | int tcp_recvmsg(struct kiocb *iocb, struct sock *sk, struct msghdr *msg, |
| 445 | size_t len, int nonblock, int flags, int *addr_len); |
| 446 | void tcp_parse_options(const struct sk_buff *skb, |
| 447 | struct tcp_options_received *opt_rx, |
| 448 | int estab, struct tcp_fastopen_cookie *foc); |
| 449 | const u8 *tcp_parse_md5sig_option(const struct tcphdr *th); |
YOSHIFUJI Hideaki | 7d5d552 | 2008-04-17 12:29:53 +0900 | [diff] [blame] | 450 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 451 | /* |
| 452 | * TCP v4 functions exported for the inet6 API |
| 453 | */ |
| 454 | |
Joe Perches | 5c9f302 | 2013-09-23 11:33:32 -0700 | [diff] [blame] | 455 | void tcp_v4_send_check(struct sock *sk, struct sk_buff *skb); |
| 456 | int tcp_v4_conn_request(struct sock *sk, struct sk_buff *skb); |
| 457 | struct sock *tcp_create_openreq_child(struct sock *sk, |
| 458 | struct request_sock *req, |
| 459 | struct sk_buff *skb); |
| 460 | struct sock *tcp_v4_syn_recv_sock(struct sock *sk, struct sk_buff *skb, |
| 461 | struct request_sock *req, |
| 462 | struct dst_entry *dst); |
| 463 | int tcp_v4_do_rcv(struct sock *sk, struct sk_buff *skb); |
| 464 | int tcp_v4_connect(struct sock *sk, struct sockaddr *uaddr, int addr_len); |
| 465 | int tcp_connect(struct sock *sk); |
| 466 | struct sk_buff *tcp_make_synack(struct sock *sk, struct dst_entry *dst, |
| 467 | struct request_sock *req, |
| 468 | struct tcp_fastopen_cookie *foc); |
| 469 | int tcp_disconnect(struct sock *sk, int flags); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 470 | |
Pavel Emelyanov | 370816a | 2012-04-19 03:40:01 +0000 | [diff] [blame] | 471 | void tcp_connect_init(struct sock *sk); |
| 472 | void tcp_finish_connect(struct sock *sk, struct sk_buff *skb); |
Pavel Emelyanov | 292e8d8 | 2012-05-10 01:49:41 +0000 | [diff] [blame] | 473 | int tcp_send_rcvq(struct sock *sk, struct msghdr *msg, size_t size); |
Eric Dumazet | 63d02d1 | 2012-08-09 14:11:00 +0000 | [diff] [blame] | 474 | void inet_sk_rx_dst_set(struct sock *sk, const struct sk_buff *skb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 475 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 476 | /* From syncookies.c */ |
Joe Perches | 5c9f302 | 2013-09-23 11:33:32 -0700 | [diff] [blame] | 477 | int __cookie_v4_check(const struct iphdr *iph, const struct tcphdr *th, |
| 478 | u32 cookie); |
| 479 | struct sock *cookie_v4_check(struct sock *sk, struct sk_buff *skb, |
| 480 | struct ip_options *opt); |
Eric Dumazet | e05c82d | 2011-09-18 21:02:55 -0400 | [diff] [blame] | 481 | #ifdef CONFIG_SYN_COOKIES |
Florian Westphal | 8c27bd7 | 2013-09-20 22:32:55 +0200 | [diff] [blame] | 482 | #include <linux/ktime.h> |
| 483 | |
| 484 | /* Syncookies use a monotonic timer which increments every 64 seconds. |
| 485 | * This counter is used both as a hash input and partially encoded into |
| 486 | * the cookie value. A cookie is only validated further if the delta |
| 487 | * between the current counter value and the encoded one is less than this, |
| 488 | * i.e. a sent cookie is valid only at most for 128 seconds (or less if |
| 489 | * the counter advances immediately after a cookie is generated). |
| 490 | */ |
| 491 | #define MAX_SYNCOOKIE_AGE 2 |
| 492 | |
| 493 | static inline u32 tcp_cookie_time(void) |
| 494 | { |
| 495 | struct timespec now; |
| 496 | getnstimeofday(&now); |
| 497 | return now.tv_sec >> 6; /* 64 seconds granularity */ |
| 498 | } |
| 499 | |
Joe Perches | 5c9f302 | 2013-09-23 11:33:32 -0700 | [diff] [blame] | 500 | u32 __cookie_v4_init_sequence(const struct iphdr *iph, const struct tcphdr *th, |
| 501 | u16 *mssp); |
| 502 | __u32 cookie_v4_init_sequence(struct sock *sk, struct sk_buff *skb, __u16 *mss); |
Eric Dumazet | e05c82d | 2011-09-18 21:02:55 -0400 | [diff] [blame] | 503 | #else |
| 504 | static inline __u32 cookie_v4_init_sequence(struct sock *sk, |
| 505 | struct sk_buff *skb, |
| 506 | __u16 *mss) |
| 507 | { |
| 508 | return 0; |
| 509 | } |
| 510 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 511 | |
Joe Perches | 5c9f302 | 2013-09-23 11:33:32 -0700 | [diff] [blame] | 512 | __u32 cookie_init_timestamp(struct request_sock *req); |
| 513 | bool cookie_check_timestamp(struct tcp_options_received *opt, struct net *net, |
| 514 | bool *ecn_ok); |
Florian Westphal | 4dfc281 | 2008-04-10 03:12:40 -0700 | [diff] [blame] | 515 | |
Glenn Griffin | c6aefaf | 2008-02-07 21:49:26 -0800 | [diff] [blame] | 516 | /* From net/ipv6/syncookies.c */ |
Joe Perches | 5c9f302 | 2013-09-23 11:33:32 -0700 | [diff] [blame] | 517 | int __cookie_v6_check(const struct ipv6hdr *iph, const struct tcphdr *th, |
| 518 | u32 cookie); |
| 519 | struct sock *cookie_v6_check(struct sock *sk, struct sk_buff *skb); |
Eric Dumazet | e05c82d | 2011-09-18 21:02:55 -0400 | [diff] [blame] | 520 | #ifdef CONFIG_SYN_COOKIES |
Joe Perches | 5c9f302 | 2013-09-23 11:33:32 -0700 | [diff] [blame] | 521 | u32 __cookie_v6_init_sequence(const struct ipv6hdr *iph, |
| 522 | const struct tcphdr *th, u16 *mssp); |
| 523 | __u32 cookie_v6_init_sequence(struct sock *sk, const struct sk_buff *skb, |
| 524 | __u16 *mss); |
Eric Dumazet | e05c82d | 2011-09-18 21:02:55 -0400 | [diff] [blame] | 525 | #else |
| 526 | static inline __u32 cookie_v6_init_sequence(struct sock *sk, |
| 527 | struct sk_buff *skb, |
| 528 | __u16 *mss) |
| 529 | { |
| 530 | return 0; |
| 531 | } |
| 532 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 533 | /* tcp_output.c */ |
| 534 | |
Joe Perches | 5c9f302 | 2013-09-23 11:33:32 -0700 | [diff] [blame] | 535 | void __tcp_push_pending_frames(struct sock *sk, unsigned int cur_mss, |
| 536 | int nonagle); |
| 537 | bool tcp_may_send_now(struct sock *sk); |
| 538 | int __tcp_retransmit_skb(struct sock *, struct sk_buff *); |
| 539 | int tcp_retransmit_skb(struct sock *, struct sk_buff *); |
| 540 | void tcp_retransmit_timer(struct sock *sk); |
| 541 | void tcp_xmit_retransmit_queue(struct sock *); |
| 542 | void tcp_simple_retransmit(struct sock *); |
| 543 | int tcp_trim_head(struct sock *, struct sk_buff *, u32); |
| 544 | int tcp_fragment(struct sock *, struct sk_buff *, u32, unsigned int); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 545 | |
Joe Perches | 5c9f302 | 2013-09-23 11:33:32 -0700 | [diff] [blame] | 546 | void tcp_send_probe0(struct sock *); |
| 547 | void tcp_send_partial(struct sock *); |
| 548 | int tcp_write_wakeup(struct sock *); |
| 549 | void tcp_send_fin(struct sock *sk); |
| 550 | void tcp_send_active_reset(struct sock *sk, gfp_t priority); |
| 551 | int tcp_send_synack(struct sock *); |
| 552 | bool tcp_syn_flood_action(struct sock *sk, const struct sk_buff *skb, |
| 553 | const char *proto); |
| 554 | void tcp_push_one(struct sock *, unsigned int mss_now); |
| 555 | void tcp_send_ack(struct sock *sk); |
| 556 | void tcp_send_delayed_ack(struct sock *sk); |
| 557 | void tcp_send_loss_probe(struct sock *sk); |
| 558 | bool tcp_schedule_loss_probe(struct sock *sk); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 559 | |
David S. Miller | a762a98 | 2005-07-05 15:18:51 -0700 | [diff] [blame] | 560 | /* tcp_input.c */ |
Joe Perches | 5c9f302 | 2013-09-23 11:33:32 -0700 | [diff] [blame] | 561 | void tcp_cwnd_application_limited(struct sock *sk); |
| 562 | void tcp_resume_early_retransmit(struct sock *sk); |
| 563 | void tcp_rearm_rto(struct sock *sk); |
| 564 | void tcp_reset(struct sock *sk); |
David S. Miller | a762a98 | 2005-07-05 15:18:51 -0700 | [diff] [blame] | 565 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 566 | /* tcp_timer.c */ |
Joe Perches | 5c9f302 | 2013-09-23 11:33:32 -0700 | [diff] [blame] | 567 | void tcp_init_xmit_timers(struct sock *); |
Arnaldo Carvalho de Melo | 463c84b | 2005-08-09 20:10:42 -0700 | [diff] [blame] | 568 | static inline void tcp_clear_xmit_timers(struct sock *sk) |
| 569 | { |
| 570 | inet_csk_clear_xmit_timers(sk); |
| 571 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 572 | |
Joe Perches | 5c9f302 | 2013-09-23 11:33:32 -0700 | [diff] [blame] | 573 | unsigned int tcp_sync_mss(struct sock *sk, u32 pmtu); |
| 574 | unsigned int tcp_current_mss(struct sock *sk); |
Ilpo Järvinen | 0c54b85 | 2009-03-14 14:23:05 +0000 | [diff] [blame] | 575 | |
| 576 | /* Bound MSS / TSO packet size with the half of the window */ |
| 577 | static inline int tcp_bound_to_half_wnd(struct tcp_sock *tp, int pktsize) |
| 578 | { |
Alexey Kuznetsov | 01f83d6 | 2010-09-15 10:27:52 -0700 | [diff] [blame] | 579 | int cutoff; |
| 580 | |
| 581 | /* When peer uses tiny windows, there is no use in packetizing |
| 582 | * to sub-MSS pieces for the sake of SWS or making sure there |
| 583 | * are enough packets in the pipe for fast recovery. |
| 584 | * |
| 585 | * On the other hand, for extremely large MSS devices, handling |
| 586 | * smaller than MSS windows in this way does make sense. |
| 587 | */ |
| 588 | if (tp->max_window >= 512) |
| 589 | cutoff = (tp->max_window >> 1); |
| 590 | else |
| 591 | cutoff = tp->max_window; |
| 592 | |
| 593 | if (cutoff && pktsize > cutoff) |
| 594 | return max_t(int, cutoff, 68U - tp->tcp_header_len); |
Ilpo Järvinen | 0c54b85 | 2009-03-14 14:23:05 +0000 | [diff] [blame] | 595 | else |
| 596 | return pktsize; |
| 597 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 598 | |
Arnaldo Carvalho de Melo | 17b085e | 2005-08-12 12:59:17 -0300 | [diff] [blame] | 599 | /* tcp.c */ |
Joe Perches | 5c9f302 | 2013-09-23 11:33:32 -0700 | [diff] [blame] | 600 | void tcp_get_info(const struct sock *, struct tcp_info *); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 601 | |
| 602 | /* Read 'sendfile()'-style from a TCP socket */ |
| 603 | typedef int (*sk_read_actor_t)(read_descriptor_t *, struct sk_buff *, |
| 604 | unsigned int, size_t); |
Joe Perches | 5c9f302 | 2013-09-23 11:33:32 -0700 | [diff] [blame] | 605 | int tcp_read_sock(struct sock *sk, read_descriptor_t *desc, |
| 606 | sk_read_actor_t recv_actor); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 607 | |
Joe Perches | 5c9f302 | 2013-09-23 11:33:32 -0700 | [diff] [blame] | 608 | void tcp_initialize_rcv_mss(struct sock *sk); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 609 | |
Joe Perches | 5c9f302 | 2013-09-23 11:33:32 -0700 | [diff] [blame] | 610 | int tcp_mtu_to_mss(struct sock *sk, int pmtu); |
| 611 | int tcp_mss_to_mtu(struct sock *sk, int mss); |
| 612 | void tcp_mtup_init(struct sock *sk); |
| 613 | void tcp_init_buffer_space(struct sock *sk); |
John Heffner | 5d424d5 | 2006-03-20 17:53:41 -0800 | [diff] [blame] | 614 | |
Damian Lukowski | f1ecd5d | 2009-08-26 00:16:31 +0000 | [diff] [blame] | 615 | static inline void tcp_bound_rto(const struct sock *sk) |
| 616 | { |
| 617 | if (inet_csk(sk)->icsk_rto > TCP_RTO_MAX) |
| 618 | inet_csk(sk)->icsk_rto = TCP_RTO_MAX; |
| 619 | } |
| 620 | |
| 621 | static inline u32 __tcp_set_rto(const struct tcp_sock *tp) |
| 622 | { |
| 623 | return (tp->srtt >> 3) + tp->rttvar; |
| 624 | } |
| 625 | |
Joe Perches | 5c9f302 | 2013-09-23 11:33:32 -0700 | [diff] [blame] | 626 | void tcp_set_rto(struct sock *sk); |
David S. Miller | 4aabd8e | 2012-07-09 16:07:30 -0700 | [diff] [blame] | 627 | |
Stephen Hemminger | 40efc6f | 2006-01-03 16:03:49 -0800 | [diff] [blame] | 628 | static inline void __tcp_fast_path_on(struct tcp_sock *tp, u32 snd_wnd) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 629 | { |
| 630 | tp->pred_flags = htonl((tp->tcp_header_len << 26) | |
| 631 | ntohl(TCP_FLAG_ACK) | |
| 632 | snd_wnd); |
| 633 | } |
| 634 | |
Stephen Hemminger | 40efc6f | 2006-01-03 16:03:49 -0800 | [diff] [blame] | 635 | static inline void tcp_fast_path_on(struct tcp_sock *tp) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 636 | { |
| 637 | __tcp_fast_path_on(tp, tp->snd_wnd >> tp->rx_opt.snd_wscale); |
| 638 | } |
| 639 | |
Ilpo Järvinen | 9e412ba | 2007-04-20 22:18:02 -0700 | [diff] [blame] | 640 | static inline void tcp_fast_path_check(struct sock *sk) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 641 | { |
Ilpo Järvinen | 9e412ba | 2007-04-20 22:18:02 -0700 | [diff] [blame] | 642 | struct tcp_sock *tp = tcp_sk(sk); |
| 643 | |
David S. Miller | b03efcf | 2005-07-08 14:57:23 -0700 | [diff] [blame] | 644 | if (skb_queue_empty(&tp->out_of_order_queue) && |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 645 | tp->rcv_wnd && |
| 646 | atomic_read(&sk->sk_rmem_alloc) < sk->sk_rcvbuf && |
| 647 | !tp->urg_data) |
| 648 | tcp_fast_path_on(tp); |
| 649 | } |
| 650 | |
Satoru SATOH | 0c26689 | 2009-05-04 11:11:01 -0700 | [diff] [blame] | 651 | /* Compute the actual rto_min value */ |
| 652 | static inline u32 tcp_rto_min(struct sock *sk) |
| 653 | { |
Eric Dumazet | cf533ea | 2011-10-21 05:22:42 -0400 | [diff] [blame] | 654 | const struct dst_entry *dst = __sk_dst_get(sk); |
Satoru SATOH | 0c26689 | 2009-05-04 11:11:01 -0700 | [diff] [blame] | 655 | u32 rto_min = TCP_RTO_MIN; |
| 656 | |
| 657 | if (dst && dst_metric_locked(dst, RTAX_RTO_MIN)) |
| 658 | rto_min = dst_metric_rtt(dst, RTAX_RTO_MIN); |
| 659 | return rto_min; |
| 660 | } |
| 661 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 662 | /* Compute the actual receive window we are currently advertising. |
| 663 | * Rcv_nxt can be after the window if our peer push more data |
| 664 | * than the offered window. |
| 665 | */ |
Stephen Hemminger | 40efc6f | 2006-01-03 16:03:49 -0800 | [diff] [blame] | 666 | static inline u32 tcp_receive_window(const struct tcp_sock *tp) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 667 | { |
| 668 | s32 win = tp->rcv_wup + tp->rcv_wnd - tp->rcv_nxt; |
| 669 | |
| 670 | if (win < 0) |
| 671 | win = 0; |
| 672 | return (u32) win; |
| 673 | } |
| 674 | |
| 675 | /* Choose a new window, without checks for shrinking, and without |
| 676 | * scaling applied to the result. The caller does these things |
| 677 | * if necessary. This is a "raw" window selection. |
| 678 | */ |
Joe Perches | 5c9f302 | 2013-09-23 11:33:32 -0700 | [diff] [blame] | 679 | u32 __tcp_select_window(struct sock *sk); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 680 | |
Pavel Emelyanov | ee99528 | 2012-04-19 03:40:39 +0000 | [diff] [blame] | 681 | void tcp_send_window_probe(struct sock *sk); |
| 682 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 683 | /* TCP timestamps are only 32-bits, this causes a slight |
| 684 | * complication on 64-bit systems since we store a snapshot |
Stephen Hemminger | 31f3426 | 2005-11-15 15:17:10 -0800 | [diff] [blame] | 685 | * of jiffies in the buffer control blocks below. We decided |
| 686 | * to use only the low 32-bits of jiffies and hide the ugly |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 687 | * casts with the following macro. |
| 688 | */ |
| 689 | #define tcp_time_stamp ((__u32)(jiffies)) |
| 690 | |
Changli Gao | a3433f3 | 2010-06-12 14:01:43 +0000 | [diff] [blame] | 691 | #define tcp_flag_byte(th) (((u_int8_t *)th)[13]) |
| 692 | |
| 693 | #define TCPHDR_FIN 0x01 |
| 694 | #define TCPHDR_SYN 0x02 |
| 695 | #define TCPHDR_RST 0x04 |
| 696 | #define TCPHDR_PSH 0x08 |
| 697 | #define TCPHDR_ACK 0x10 |
| 698 | #define TCPHDR_URG 0x20 |
| 699 | #define TCPHDR_ECE 0x40 |
| 700 | #define TCPHDR_CWR 0x80 |
| 701 | |
Stephen Hemminger | caa20d9a | 2005-11-10 17:13:47 -0800 | [diff] [blame] | 702 | /* This is what the send packet queuing engine uses to pass |
Eric Dumazet | f86586f | 2010-07-15 21:41:00 -0700 | [diff] [blame] | 703 | * TCP per-packet control information to the transmission code. |
| 704 | * We also store the host-order sequence numbers in here too. |
| 705 | * This is 44 bytes if IPV6 is enabled. |
| 706 | * If this grows please adjust skbuff.h:skbuff->cb[xxx] size appropriately. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 707 | */ |
| 708 | struct tcp_skb_cb { |
| 709 | union { |
| 710 | struct inet_skb_parm h4; |
Eric Dumazet | dfd56b8 | 2011-12-10 09:48:31 +0000 | [diff] [blame] | 711 | #if IS_ENABLED(CONFIG_IPV6) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 712 | struct inet6_skb_parm h6; |
| 713 | #endif |
| 714 | } header; /* For incoming frames */ |
| 715 | __u32 seq; /* Starting sequence number */ |
| 716 | __u32 end_seq; /* SEQ + FIN + SYN + datalen */ |
| 717 | __u32 when; /* used to compute rtt's */ |
Eric Dumazet | 4de075e | 2011-09-27 13:25:05 -0400 | [diff] [blame] | 718 | __u8 tcp_flags; /* TCP header flags. (tcp[13]) */ |
Neal Cardwell | f4f9f6e | 2012-04-16 07:08:06 +0000 | [diff] [blame] | 719 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 720 | __u8 sacked; /* State flags for SACK/FACK. */ |
| 721 | #define TCPCB_SACKED_ACKED 0x01 /* SKB ACK'd by a SACK block */ |
| 722 | #define TCPCB_SACKED_RETRANS 0x02 /* SKB retransmitted */ |
| 723 | #define TCPCB_LOST 0x04 /* SKB is lost */ |
| 724 | #define TCPCB_TAGBITS 0x07 /* All tag bits */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 725 | #define TCPCB_EVER_RETRANS 0x80 /* Ever retransmitted frame */ |
| 726 | #define TCPCB_RETRANS (TCPCB_SACKED_RETRANS|TCPCB_EVER_RETRANS) |
| 727 | |
Neal Cardwell | f4f9f6e | 2012-04-16 07:08:06 +0000 | [diff] [blame] | 728 | __u8 ip_dsfield; /* IPv4 tos or IPv6 dsfield */ |
| 729 | /* 1 byte hole */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 730 | __u32 ack_seq; /* Sequence number ACK'd */ |
| 731 | }; |
| 732 | |
| 733 | #define TCP_SKB_CB(__skb) ((struct tcp_skb_cb *)&((__skb)->cb[0])) |
| 734 | |
Eric Dumazet | bd14b1b | 2012-05-04 05:14:02 +0000 | [diff] [blame] | 735 | /* RFC3168 : 6.1.1 SYN packets must not have ECT/ECN bits set |
| 736 | * |
| 737 | * If we receive a SYN packet with these bits set, it means a network is |
| 738 | * playing bad games with TOS bits. In order to avoid possible false congestion |
| 739 | * notifications, we disable TCP ECN negociation. |
| 740 | */ |
| 741 | static inline void |
Hannes Frederic Sowa | 5d134f1 | 2013-01-05 16:10:48 +0000 | [diff] [blame] | 742 | TCP_ECN_create_request(struct request_sock *req, const struct sk_buff *skb, |
| 743 | struct net *net) |
Eric Dumazet | bd14b1b | 2012-05-04 05:14:02 +0000 | [diff] [blame] | 744 | { |
| 745 | const struct tcphdr *th = tcp_hdr(skb); |
| 746 | |
Hannes Frederic Sowa | 5d134f1 | 2013-01-05 16:10:48 +0000 | [diff] [blame] | 747 | if (net->ipv4.sysctl_tcp_ecn && th->ece && th->cwr && |
Eric Dumazet | bd14b1b | 2012-05-04 05:14:02 +0000 | [diff] [blame] | 748 | INET_ECN_is_not_ect(TCP_SKB_CB(skb)->ip_dsfield)) |
| 749 | inet_rsk(req)->ecn_ok = 1; |
| 750 | } |
| 751 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 752 | /* Due to TSO, an SKB can be composed of multiple actual |
| 753 | * packets. To keep these tracked properly, we use this. |
| 754 | */ |
| 755 | static inline int tcp_skb_pcount(const struct sk_buff *skb) |
| 756 | { |
Herbert Xu | 7967168 | 2006-06-22 02:40:14 -0700 | [diff] [blame] | 757 | return skb_shinfo(skb)->gso_segs; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 758 | } |
| 759 | |
| 760 | /* This is valid iff tcp_skb_pcount() > 1. */ |
| 761 | static inline int tcp_skb_mss(const struct sk_buff *skb) |
| 762 | { |
Herbert Xu | 7967168 | 2006-06-22 02:40:14 -0700 | [diff] [blame] | 763 | return skb_shinfo(skb)->gso_size; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 764 | } |
| 765 | |
Stephen Hemminger | 317a76f | 2005-06-23 12:19:55 -0700 | [diff] [blame] | 766 | /* Events passed to congestion control interface */ |
| 767 | enum tcp_ca_event { |
| 768 | CA_EVENT_TX_START, /* first transmit when no packets in flight */ |
| 769 | CA_EVENT_CWND_RESTART, /* congestion window restart */ |
| 770 | CA_EVENT_COMPLETE_CWR, /* end of congestion recovery */ |
Stephen Hemminger | 317a76f | 2005-06-23 12:19:55 -0700 | [diff] [blame] | 771 | CA_EVENT_LOSS, /* loss timeout */ |
| 772 | CA_EVENT_FAST_ACK, /* in sequence ack */ |
| 773 | CA_EVENT_SLOW_ACK, /* other ack */ |
| 774 | }; |
| 775 | |
| 776 | /* |
| 777 | * Interface for adding new TCP congestion control handlers |
| 778 | */ |
| 779 | #define TCP_CA_NAME_MAX 16 |
Stephen Hemminger | 3ff825b | 2006-11-09 16:32:06 -0800 | [diff] [blame] | 780 | #define TCP_CA_MAX 128 |
| 781 | #define TCP_CA_BUF_MAX (TCP_CA_NAME_MAX*TCP_CA_MAX) |
| 782 | |
Stephen Hemminger | 164891a | 2007-04-23 22:26:16 -0700 | [diff] [blame] | 783 | #define TCP_CONG_NON_RESTRICTED 0x1 |
| 784 | #define TCP_CONG_RTT_STAMP 0x2 |
| 785 | |
Stephen Hemminger | 317a76f | 2005-06-23 12:19:55 -0700 | [diff] [blame] | 786 | struct tcp_congestion_ops { |
| 787 | struct list_head list; |
Stephen Hemminger | 164891a | 2007-04-23 22:26:16 -0700 | [diff] [blame] | 788 | unsigned long flags; |
Stephen Hemminger | 317a76f | 2005-06-23 12:19:55 -0700 | [diff] [blame] | 789 | |
| 790 | /* initialize private data (optional) */ |
Arnaldo Carvalho de Melo | 6687e98 | 2005-08-10 04:03:31 -0300 | [diff] [blame] | 791 | void (*init)(struct sock *sk); |
Stephen Hemminger | 317a76f | 2005-06-23 12:19:55 -0700 | [diff] [blame] | 792 | /* cleanup private data (optional) */ |
Arnaldo Carvalho de Melo | 6687e98 | 2005-08-10 04:03:31 -0300 | [diff] [blame] | 793 | void (*release)(struct sock *sk); |
Stephen Hemminger | 317a76f | 2005-06-23 12:19:55 -0700 | [diff] [blame] | 794 | |
| 795 | /* return slow start threshold (required) */ |
Arnaldo Carvalho de Melo | 6687e98 | 2005-08-10 04:03:31 -0300 | [diff] [blame] | 796 | u32 (*ssthresh)(struct sock *sk); |
Stephen Hemminger | 317a76f | 2005-06-23 12:19:55 -0700 | [diff] [blame] | 797 | /* lower bound for congestion window (optional) */ |
Stephen Hemminger | 72dc5b9 | 2006-06-05 17:30:08 -0700 | [diff] [blame] | 798 | u32 (*min_cwnd)(const struct sock *sk); |
Stephen Hemminger | 317a76f | 2005-06-23 12:19:55 -0700 | [diff] [blame] | 799 | /* do new cwnd calculation (required) */ |
Yuchung Cheng | 9f9843a7 | 2013-10-31 11:07:31 -0700 | [diff] [blame] | 800 | void (*cong_avoid)(struct sock *sk, u32 ack, u32 acked, u32 in_flight); |
Stephen Hemminger | 317a76f | 2005-06-23 12:19:55 -0700 | [diff] [blame] | 801 | /* call before changing ca_state (optional) */ |
Arnaldo Carvalho de Melo | 6687e98 | 2005-08-10 04:03:31 -0300 | [diff] [blame] | 802 | void (*set_state)(struct sock *sk, u8 new_state); |
Stephen Hemminger | 317a76f | 2005-06-23 12:19:55 -0700 | [diff] [blame] | 803 | /* call when cwnd event occurs (optional) */ |
Arnaldo Carvalho de Melo | 6687e98 | 2005-08-10 04:03:31 -0300 | [diff] [blame] | 804 | void (*cwnd_event)(struct sock *sk, enum tcp_ca_event ev); |
Stephen Hemminger | 317a76f | 2005-06-23 12:19:55 -0700 | [diff] [blame] | 805 | /* new value of cwnd after loss (optional) */ |
Arnaldo Carvalho de Melo | 6687e98 | 2005-08-10 04:03:31 -0300 | [diff] [blame] | 806 | u32 (*undo_cwnd)(struct sock *sk); |
Stephen Hemminger | 317a76f | 2005-06-23 12:19:55 -0700 | [diff] [blame] | 807 | /* hook for packet ack accounting (optional) */ |
Stephen Hemminger | 30cfd0b | 2007-07-25 23:49:34 -0700 | [diff] [blame] | 808 | void (*pkts_acked)(struct sock *sk, u32 num_acked, s32 rtt_us); |
Arnaldo Carvalho de Melo | 73c1f4a | 2005-08-12 12:51:49 -0300 | [diff] [blame] | 809 | /* get info for inet_diag (optional) */ |
Arnaldo Carvalho de Melo | 6687e98 | 2005-08-10 04:03:31 -0300 | [diff] [blame] | 810 | void (*get_info)(struct sock *sk, u32 ext, struct sk_buff *skb); |
Stephen Hemminger | 317a76f | 2005-06-23 12:19:55 -0700 | [diff] [blame] | 811 | |
| 812 | char name[TCP_CA_NAME_MAX]; |
| 813 | struct module *owner; |
| 814 | }; |
| 815 | |
Joe Perches | 5c9f302 | 2013-09-23 11:33:32 -0700 | [diff] [blame] | 816 | int tcp_register_congestion_control(struct tcp_congestion_ops *type); |
| 817 | void tcp_unregister_congestion_control(struct tcp_congestion_ops *type); |
Stephen Hemminger | 317a76f | 2005-06-23 12:19:55 -0700 | [diff] [blame] | 818 | |
Joe Perches | 5c9f302 | 2013-09-23 11:33:32 -0700 | [diff] [blame] | 819 | void tcp_init_congestion_control(struct sock *sk); |
| 820 | void tcp_cleanup_congestion_control(struct sock *sk); |
| 821 | int tcp_set_default_congestion_control(const char *name); |
| 822 | void tcp_get_default_congestion_control(char *name); |
| 823 | void tcp_get_available_congestion_control(char *buf, size_t len); |
| 824 | void tcp_get_allowed_congestion_control(char *buf, size_t len); |
| 825 | int tcp_set_allowed_congestion_control(char *allowed); |
| 826 | int tcp_set_congestion_control(struct sock *sk, const char *name); |
Yuchung Cheng | 9f9843a7 | 2013-10-31 11:07:31 -0700 | [diff] [blame] | 827 | int tcp_slow_start(struct tcp_sock *tp, u32 acked); |
Joe Perches | 5c9f302 | 2013-09-23 11:33:32 -0700 | [diff] [blame] | 828 | void tcp_cong_avoid_ai(struct tcp_sock *tp, u32 w); |
Stephen Hemminger | 317a76f | 2005-06-23 12:19:55 -0700 | [diff] [blame] | 829 | |
Stephen Hemminger | 5f8ef48 | 2005-06-23 20:37:36 -0700 | [diff] [blame] | 830 | extern struct tcp_congestion_ops tcp_init_congestion_ops; |
Joe Perches | 5c9f302 | 2013-09-23 11:33:32 -0700 | [diff] [blame] | 831 | u32 tcp_reno_ssthresh(struct sock *sk); |
Yuchung Cheng | 9f9843a7 | 2013-10-31 11:07:31 -0700 | [diff] [blame] | 832 | void tcp_reno_cong_avoid(struct sock *sk, u32 ack, u32 acked, u32 in_flight); |
Joe Perches | 5c9f302 | 2013-09-23 11:33:32 -0700 | [diff] [blame] | 833 | u32 tcp_reno_min_cwnd(const struct sock *sk); |
David S. Miller | a8acfba | 2005-06-23 23:45:02 -0700 | [diff] [blame] | 834 | extern struct tcp_congestion_ops tcp_reno; |
Stephen Hemminger | 317a76f | 2005-06-23 12:19:55 -0700 | [diff] [blame] | 835 | |
Arnaldo Carvalho de Melo | 6687e98 | 2005-08-10 04:03:31 -0300 | [diff] [blame] | 836 | static inline void tcp_set_ca_state(struct sock *sk, const u8 ca_state) |
Stephen Hemminger | 317a76f | 2005-06-23 12:19:55 -0700 | [diff] [blame] | 837 | { |
Arnaldo Carvalho de Melo | 6687e98 | 2005-08-10 04:03:31 -0300 | [diff] [blame] | 838 | struct inet_connection_sock *icsk = inet_csk(sk); |
| 839 | |
| 840 | if (icsk->icsk_ca_ops->set_state) |
| 841 | icsk->icsk_ca_ops->set_state(sk, ca_state); |
| 842 | icsk->icsk_ca_state = ca_state; |
Stephen Hemminger | 317a76f | 2005-06-23 12:19:55 -0700 | [diff] [blame] | 843 | } |
| 844 | |
Arnaldo Carvalho de Melo | 6687e98 | 2005-08-10 04:03:31 -0300 | [diff] [blame] | 845 | static inline void tcp_ca_event(struct sock *sk, const enum tcp_ca_event event) |
Stephen Hemminger | 317a76f | 2005-06-23 12:19:55 -0700 | [diff] [blame] | 846 | { |
Arnaldo Carvalho de Melo | 6687e98 | 2005-08-10 04:03:31 -0300 | [diff] [blame] | 847 | const struct inet_connection_sock *icsk = inet_csk(sk); |
| 848 | |
| 849 | if (icsk->icsk_ca_ops->cwnd_event) |
| 850 | icsk->icsk_ca_ops->cwnd_event(sk, event); |
Stephen Hemminger | 317a76f | 2005-06-23 12:19:55 -0700 | [diff] [blame] | 851 | } |
| 852 | |
Ilpo Järvinen | e60402d | 2007-08-09 15:14:46 +0300 | [diff] [blame] | 853 | /* These functions determine how the current flow behaves in respect of SACK |
| 854 | * handling. SACK is negotiated with the peer, and therefore it can vary |
| 855 | * between different flows. |
| 856 | * |
| 857 | * tcp_is_sack - SACK enabled |
| 858 | * tcp_is_reno - No SACK |
| 859 | * tcp_is_fack - FACK enabled, implies SACK enabled |
| 860 | */ |
| 861 | static inline int tcp_is_sack(const struct tcp_sock *tp) |
| 862 | { |
| 863 | return tp->rx_opt.sack_ok; |
| 864 | } |
| 865 | |
Eric Dumazet | a2a385d | 2012-05-16 23:15:34 +0000 | [diff] [blame] | 866 | static inline bool tcp_is_reno(const struct tcp_sock *tp) |
Ilpo Järvinen | e60402d | 2007-08-09 15:14:46 +0300 | [diff] [blame] | 867 | { |
| 868 | return !tcp_is_sack(tp); |
| 869 | } |
| 870 | |
Eric Dumazet | a2a385d | 2012-05-16 23:15:34 +0000 | [diff] [blame] | 871 | static inline bool tcp_is_fack(const struct tcp_sock *tp) |
Ilpo Järvinen | e60402d | 2007-08-09 15:14:46 +0300 | [diff] [blame] | 872 | { |
Vijay Subramanian | ab56222 | 2011-12-20 13:23:24 +0000 | [diff] [blame] | 873 | return tp->rx_opt.sack_ok & TCP_FACK_ENABLED; |
Ilpo Järvinen | e60402d | 2007-08-09 15:14:46 +0300 | [diff] [blame] | 874 | } |
| 875 | |
| 876 | static inline void tcp_enable_fack(struct tcp_sock *tp) |
| 877 | { |
Vijay Subramanian | ab56222 | 2011-12-20 13:23:24 +0000 | [diff] [blame] | 878 | tp->rx_opt.sack_ok |= TCP_FACK_ENABLED; |
Ilpo Järvinen | e60402d | 2007-08-09 15:14:46 +0300 | [diff] [blame] | 879 | } |
| 880 | |
Yuchung Cheng | eed530b | 2012-05-02 13:30:03 +0000 | [diff] [blame] | 881 | /* TCP early-retransmit (ER) is similar to but more conservative than |
| 882 | * the thin-dupack feature. Enable ER only if thin-dupack is disabled. |
| 883 | */ |
| 884 | static inline void tcp_enable_early_retrans(struct tcp_sock *tp) |
| 885 | { |
| 886 | tp->do_early_retrans = sysctl_tcp_early_retrans && |
Nandita Dukkipati | 6ba8a3b | 2013-03-11 10:00:43 +0000 | [diff] [blame] | 887 | sysctl_tcp_early_retrans < 4 && !sysctl_tcp_thin_dupack && |
| 888 | sysctl_tcp_reordering == 3; |
Yuchung Cheng | eed530b | 2012-05-02 13:30:03 +0000 | [diff] [blame] | 889 | } |
| 890 | |
| 891 | static inline void tcp_disable_early_retrans(struct tcp_sock *tp) |
| 892 | { |
| 893 | tp->do_early_retrans = 0; |
| 894 | } |
| 895 | |
Ilpo Järvinen | 83ae408 | 2007-08-09 14:37:30 +0300 | [diff] [blame] | 896 | static inline unsigned int tcp_left_out(const struct tcp_sock *tp) |
| 897 | { |
| 898 | return tp->sacked_out + tp->lost_out; |
| 899 | } |
| 900 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 901 | /* This determines how many packets are "in the network" to the best |
| 902 | * of our knowledge. In many cases it is conservative, but where |
| 903 | * detailed information is available from the receiver (via SACK |
| 904 | * blocks etc.) we can make more aggressive calculations. |
| 905 | * |
| 906 | * Use this for decisions involving congestion control, use just |
| 907 | * tp->packets_out to determine if the send queue is empty or not. |
| 908 | * |
| 909 | * Read this equation as: |
| 910 | * |
| 911 | * "Packets sent once on transmission queue" MINUS |
| 912 | * "Packets left network, but not honestly ACKed yet" PLUS |
| 913 | * "Packets fast retransmitted" |
| 914 | */ |
Stephen Hemminger | 40efc6f | 2006-01-03 16:03:49 -0800 | [diff] [blame] | 915 | static inline unsigned int tcp_packets_in_flight(const struct tcp_sock *tp) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 916 | { |
Ilpo Järvinen | 83ae408 | 2007-08-09 14:37:30 +0300 | [diff] [blame] | 917 | return tp->packets_out - tcp_left_out(tp) + tp->retrans_out; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 918 | } |
| 919 | |
Ilpo Järvinen | 0b6a05c | 2009-09-15 01:30:10 -0700 | [diff] [blame] | 920 | #define TCP_INFINITE_SSTHRESH 0x7fffffff |
| 921 | |
| 922 | static inline bool tcp_in_initial_slowstart(const struct tcp_sock *tp) |
| 923 | { |
| 924 | return tp->snd_ssthresh >= TCP_INFINITE_SSTHRESH; |
| 925 | } |
| 926 | |
Yuchung Cheng | 684bad1 | 2012-09-02 17:38:04 +0000 | [diff] [blame] | 927 | static inline bool tcp_in_cwnd_reduction(const struct sock *sk) |
| 928 | { |
| 929 | return (TCPF_CA_CWR | TCPF_CA_Recovery) & |
| 930 | (1 << inet_csk(sk)->icsk_ca_state); |
| 931 | } |
| 932 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 933 | /* If cwnd > ssthresh, we may raise ssthresh to be half-way to cwnd. |
Yuchung Cheng | 684bad1 | 2012-09-02 17:38:04 +0000 | [diff] [blame] | 934 | * The exception is cwnd reduction phase, when cwnd is decreasing towards |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 935 | * ssthresh. |
| 936 | */ |
Arnaldo Carvalho de Melo | 6687e98 | 2005-08-10 04:03:31 -0300 | [diff] [blame] | 937 | static inline __u32 tcp_current_ssthresh(const struct sock *sk) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 938 | { |
Arnaldo Carvalho de Melo | 6687e98 | 2005-08-10 04:03:31 -0300 | [diff] [blame] | 939 | const struct tcp_sock *tp = tcp_sk(sk); |
Eric Dumazet | cf533ea | 2011-10-21 05:22:42 -0400 | [diff] [blame] | 940 | |
Yuchung Cheng | 684bad1 | 2012-09-02 17:38:04 +0000 | [diff] [blame] | 941 | if (tcp_in_cwnd_reduction(sk)) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 942 | return tp->snd_ssthresh; |
| 943 | else |
| 944 | return max(tp->snd_ssthresh, |
| 945 | ((tp->snd_cwnd >> 1) + |
| 946 | (tp->snd_cwnd >> 2))); |
| 947 | } |
| 948 | |
Ilpo Järvinen | b9c4595 | 2007-07-27 16:36:17 +0300 | [diff] [blame] | 949 | /* Use define here intentionally to get WARN_ON location shown at the caller */ |
| 950 | #define tcp_verify_left_out(tp) WARN_ON(tcp_left_out(tp) > tp->packets_out) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 951 | |
Joe Perches | 5c9f302 | 2013-09-23 11:33:32 -0700 | [diff] [blame] | 952 | void tcp_enter_cwr(struct sock *sk, const int set_ssthresh); |
| 953 | __u32 tcp_init_cwnd(const struct tcp_sock *tp, const struct dst_entry *dst); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 954 | |
Neal Cardwell | 6b5a5c0 | 2011-11-21 17:15:14 +0000 | [diff] [blame] | 955 | /* The maximum number of MSS of available cwnd for which TSO defers |
| 956 | * sending if not using sysctl_tcp_tso_win_divisor. |
| 957 | */ |
| 958 | static inline __u32 tcp_max_tso_deferred_mss(const struct tcp_sock *tp) |
| 959 | { |
| 960 | return 3; |
| 961 | } |
| 962 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 963 | /* Slow start with delack produces 3 packets of burst, so that |
John Heffner | dd9e0dd | 2008-04-15 15:26:39 -0700 | [diff] [blame] | 964 | * it is safe "de facto". This will be the default - same as |
| 965 | * the default reordering threshold - but if reordering increases, |
| 966 | * we must be able to allow cwnd to burst at least this much in order |
| 967 | * to not pull it back when holes are filled. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 968 | */ |
| 969 | static __inline__ __u32 tcp_max_burst(const struct tcp_sock *tp) |
| 970 | { |
John Heffner | dd9e0dd | 2008-04-15 15:26:39 -0700 | [diff] [blame] | 971 | return tp->reordering; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 972 | } |
| 973 | |
Ilpo Järvinen | 90840de | 2007-12-31 04:48:41 -0800 | [diff] [blame] | 974 | /* Returns end sequence number of the receiver's advertised window */ |
| 975 | static inline u32 tcp_wnd_end(const struct tcp_sock *tp) |
| 976 | { |
| 977 | return tp->snd_una + tp->snd_wnd; |
| 978 | } |
Joe Perches | 5c9f302 | 2013-09-23 11:33:32 -0700 | [diff] [blame] | 979 | bool tcp_is_cwnd_limited(const struct sock *sk, u32 in_flight); |
Stephen Hemminger | f4805ed | 2005-11-10 16:53:30 -0800 | [diff] [blame] | 980 | |
Ilpo Järvinen | 9e412ba | 2007-04-20 22:18:02 -0700 | [diff] [blame] | 981 | static inline void tcp_check_probe_timer(struct sock *sk) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 982 | { |
Eric Dumazet | cf533ea | 2011-10-21 05:22:42 -0400 | [diff] [blame] | 983 | const struct tcp_sock *tp = tcp_sk(sk); |
Arnaldo Carvalho de Melo | 463c84b | 2005-08-09 20:10:42 -0700 | [diff] [blame] | 984 | const struct inet_connection_sock *icsk = inet_csk(sk); |
Ilpo Järvinen | 9e412ba | 2007-04-20 22:18:02 -0700 | [diff] [blame] | 985 | |
Arnaldo Carvalho de Melo | 463c84b | 2005-08-09 20:10:42 -0700 | [diff] [blame] | 986 | if (!tp->packets_out && !icsk->icsk_pending) |
Arnaldo Carvalho de Melo | 3f421ba | 2005-08-09 20:11:08 -0700 | [diff] [blame] | 987 | inet_csk_reset_xmit_timer(sk, ICSK_TIME_PROBE0, |
| 988 | icsk->icsk_rto, TCP_RTO_MAX); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 989 | } |
| 990 | |
Hantzis Fotis | ee7537b | 2009-03-02 22:42:02 -0800 | [diff] [blame] | 991 | static inline void tcp_init_wl(struct tcp_sock *tp, u32 seq) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 992 | { |
| 993 | tp->snd_wl1 = seq; |
| 994 | } |
| 995 | |
Hantzis Fotis | ee7537b | 2009-03-02 22:42:02 -0800 | [diff] [blame] | 996 | static inline void tcp_update_wl(struct tcp_sock *tp, u32 seq) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 997 | { |
| 998 | tp->snd_wl1 = seq; |
| 999 | } |
| 1000 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1001 | /* |
| 1002 | * Calculate(/check) TCP checksum |
| 1003 | */ |
Frederik Deweerdt | ba7808e | 2007-02-04 20:15:27 -0800 | [diff] [blame] | 1004 | static inline __sum16 tcp_v4_check(int len, __be32 saddr, |
| 1005 | __be32 daddr, __wsum base) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1006 | { |
| 1007 | return csum_tcpudp_magic(saddr,daddr,len,IPPROTO_TCP,base); |
| 1008 | } |
| 1009 | |
Al Viro | b51655b | 2006-11-14 21:40:42 -0800 | [diff] [blame] | 1010 | static inline __sum16 __tcp_checksum_complete(struct sk_buff *skb) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1011 | { |
Herbert Xu | fb286bb | 2005-11-10 13:01:24 -0800 | [diff] [blame] | 1012 | return __skb_checksum_complete(skb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1013 | } |
| 1014 | |
Eric Dumazet | a2a385d | 2012-05-16 23:15:34 +0000 | [diff] [blame] | 1015 | static inline bool tcp_checksum_complete(struct sk_buff *skb) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1016 | { |
Herbert Xu | 6047637 | 2007-04-09 11:59:39 -0700 | [diff] [blame] | 1017 | return !skb_csum_unnecessary(skb) && |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1018 | __tcp_checksum_complete(skb); |
| 1019 | } |
| 1020 | |
| 1021 | /* Prequeue for VJ style copy to user, combined with checksumming. */ |
| 1022 | |
Stephen Hemminger | 40efc6f | 2006-01-03 16:03:49 -0800 | [diff] [blame] | 1023 | static inline void tcp_prequeue_init(struct tcp_sock *tp) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1024 | { |
| 1025 | tp->ucopy.task = NULL; |
| 1026 | tp->ucopy.len = 0; |
| 1027 | tp->ucopy.memory = 0; |
| 1028 | skb_queue_head_init(&tp->ucopy.prequeue); |
Chris Leech | 97fc2f0 | 2006-05-23 17:55:33 -0700 | [diff] [blame] | 1029 | #ifdef CONFIG_NET_DMA |
| 1030 | tp->ucopy.dma_chan = NULL; |
| 1031 | tp->ucopy.wakeup = 0; |
| 1032 | tp->ucopy.pinned_list = NULL; |
| 1033 | tp->ucopy.dma_cookie = 0; |
| 1034 | #endif |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1035 | } |
| 1036 | |
Joe Perches | 5c9f302 | 2013-09-23 11:33:32 -0700 | [diff] [blame] | 1037 | bool tcp_prequeue(struct sock *sk, struct sk_buff *skb); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1038 | |
| 1039 | #undef STATE_TRACE |
| 1040 | |
| 1041 | #ifdef STATE_TRACE |
| 1042 | static const char *statename[]={ |
| 1043 | "Unused","Established","Syn Sent","Syn Recv", |
| 1044 | "Fin Wait 1","Fin Wait 2","Time Wait", "Close", |
| 1045 | "Close Wait","Last ACK","Listen","Closing" |
| 1046 | }; |
| 1047 | #endif |
Joe Perches | 5c9f302 | 2013-09-23 11:33:32 -0700 | [diff] [blame] | 1048 | void tcp_set_state(struct sock *sk, int state); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1049 | |
Joe Perches | 5c9f302 | 2013-09-23 11:33:32 -0700 | [diff] [blame] | 1050 | void tcp_done(struct sock *sk); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1051 | |
Stephen Hemminger | 40efc6f | 2006-01-03 16:03:49 -0800 | [diff] [blame] | 1052 | static inline void tcp_sack_reset(struct tcp_options_received *rx_opt) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1053 | { |
| 1054 | rx_opt->dsack = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1055 | rx_opt->num_sacks = 0; |
| 1056 | } |
| 1057 | |
Joe Perches | 5c9f302 | 2013-09-23 11:33:32 -0700 | [diff] [blame] | 1058 | u32 tcp_default_init_rwnd(u32 mss); |
Yuchung Cheng | 85f1652 | 2013-06-11 15:35:32 -0700 | [diff] [blame] | 1059 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1060 | /* Determine a window scaling and initial window to offer. */ |
Joe Perches | 5c9f302 | 2013-09-23 11:33:32 -0700 | [diff] [blame] | 1061 | void tcp_select_initial_window(int __space, __u32 mss, __u32 *rcv_wnd, |
| 1062 | __u32 *window_clamp, int wscale_ok, |
| 1063 | __u8 *rcv_wscale, __u32 init_rcv_wnd); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1064 | |
| 1065 | static inline int tcp_win_from_space(int space) |
| 1066 | { |
| 1067 | return sysctl_tcp_adv_win_scale<=0 ? |
| 1068 | (space>>(-sysctl_tcp_adv_win_scale)) : |
| 1069 | space - (space>>sysctl_tcp_adv_win_scale); |
| 1070 | } |
| 1071 | |
| 1072 | /* Note: caller must be prepared to deal with negative returns */ |
| 1073 | static inline int tcp_space(const struct sock *sk) |
| 1074 | { |
| 1075 | return tcp_win_from_space(sk->sk_rcvbuf - |
| 1076 | atomic_read(&sk->sk_rmem_alloc)); |
| 1077 | } |
| 1078 | |
| 1079 | static inline int tcp_full_space(const struct sock *sk) |
| 1080 | { |
| 1081 | return tcp_win_from_space(sk->sk_rcvbuf); |
| 1082 | } |
| 1083 | |
Stephen Hemminger | 40efc6f | 2006-01-03 16:03:49 -0800 | [diff] [blame] | 1084 | static inline void tcp_openreq_init(struct request_sock *req, |
| 1085 | struct tcp_options_received *rx_opt, |
| 1086 | struct sk_buff *skb) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1087 | { |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 1088 | struct inet_request_sock *ireq = inet_rsk(req); |
| 1089 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1090 | req->rcv_wnd = 0; /* So that tcp_send_synack() knows! */ |
Florian Westphal | 4dfc281 | 2008-04-10 03:12:40 -0700 | [diff] [blame] | 1091 | req->cookie_ts = 0; |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 1092 | tcp_rsk(req)->rcv_isn = TCP_SKB_CB(skb)->seq; |
Jerry Chu | 1046716 | 2012-08-31 12:29:11 +0000 | [diff] [blame] | 1093 | tcp_rsk(req)->rcv_nxt = TCP_SKB_CB(skb)->seq + 1; |
Neal Cardwell | 016818d | 2012-09-22 04:18:55 +0000 | [diff] [blame] | 1094 | tcp_rsk(req)->snt_synack = 0; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1095 | req->mss = rx_opt->mss_clamp; |
| 1096 | req->ts_recent = rx_opt->saw_tstamp ? rx_opt->rcv_tsval : 0; |
Arnaldo Carvalho de Melo | 2e6599c | 2005-06-18 22:46:52 -0700 | [diff] [blame] | 1097 | ireq->tstamp_ok = rx_opt->tstamp_ok; |
| 1098 | ireq->sack_ok = rx_opt->sack_ok; |
| 1099 | ireq->snd_wscale = rx_opt->snd_wscale; |
| 1100 | ireq->wscale_ok = rx_opt->wscale_ok; |
| 1101 | ireq->acked = 0; |
| 1102 | ireq->ecn_ok = 0; |
Eric Dumazet | 634fb979 | 2013-10-09 15:21:29 -0700 | [diff] [blame] | 1103 | ireq->ir_rmt_port = tcp_hdr(skb)->source; |
Eric Dumazet | b44084c | 2013-10-10 00:04:37 -0700 | [diff] [blame] | 1104 | ireq->ir_num = ntohs(tcp_hdr(skb)->dest); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1105 | } |
| 1106 | |
Joe Perches | 5c9f302 | 2013-09-23 11:33:32 -0700 | [diff] [blame] | 1107 | void tcp_enter_memory_pressure(struct sock *sk); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1108 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1109 | static inline int keepalive_intvl_when(const struct tcp_sock *tp) |
| 1110 | { |
| 1111 | return tp->keepalive_intvl ? : sysctl_tcp_keepalive_intvl; |
| 1112 | } |
| 1113 | |
| 1114 | static inline int keepalive_time_when(const struct tcp_sock *tp) |
| 1115 | { |
| 1116 | return tp->keepalive_time ? : sysctl_tcp_keepalive_time; |
| 1117 | } |
| 1118 | |
Eric Dumazet | df19a62 | 2009-08-28 23:48:54 -0700 | [diff] [blame] | 1119 | static inline int keepalive_probes(const struct tcp_sock *tp) |
| 1120 | { |
| 1121 | return tp->keepalive_probes ? : sysctl_tcp_keepalive_probes; |
| 1122 | } |
| 1123 | |
Flavio Leitner | 6c37e5d | 2010-04-26 18:33:27 +0000 | [diff] [blame] | 1124 | static inline u32 keepalive_time_elapsed(const struct tcp_sock *tp) |
| 1125 | { |
| 1126 | const struct inet_connection_sock *icsk = &tp->inet_conn; |
| 1127 | |
| 1128 | return min_t(u32, tcp_time_stamp - icsk->icsk_ack.lrcvtime, |
| 1129 | tcp_time_stamp - tp->rcv_tstamp); |
| 1130 | } |
| 1131 | |
Arnaldo Carvalho de Melo | 463c84b | 2005-08-09 20:10:42 -0700 | [diff] [blame] | 1132 | static inline int tcp_fin_time(const struct sock *sk) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1133 | { |
Arnaldo Carvalho de Melo | 463c84b | 2005-08-09 20:10:42 -0700 | [diff] [blame] | 1134 | int fin_timeout = tcp_sk(sk)->linger2 ? : sysctl_tcp_fin_timeout; |
| 1135 | const int rto = inet_csk(sk)->icsk_rto; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1136 | |
Arnaldo Carvalho de Melo | 463c84b | 2005-08-09 20:10:42 -0700 | [diff] [blame] | 1137 | if (fin_timeout < (rto << 2) - (rto >> 1)) |
| 1138 | fin_timeout = (rto << 2) - (rto >> 1); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1139 | |
| 1140 | return fin_timeout; |
| 1141 | } |
| 1142 | |
Eric Dumazet | a2a385d | 2012-05-16 23:15:34 +0000 | [diff] [blame] | 1143 | static inline bool tcp_paws_check(const struct tcp_options_received *rx_opt, |
| 1144 | int paws_win) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1145 | { |
Ilpo Järvinen | c887e6d | 2009-03-14 14:23:03 +0000 | [diff] [blame] | 1146 | if ((s32)(rx_opt->ts_recent - rx_opt->rcv_tsval) <= paws_win) |
Eric Dumazet | a2a385d | 2012-05-16 23:15:34 +0000 | [diff] [blame] | 1147 | return true; |
Ilpo Järvinen | c887e6d | 2009-03-14 14:23:03 +0000 | [diff] [blame] | 1148 | if (unlikely(get_seconds() >= rx_opt->ts_recent_stamp + TCP_PAWS_24DAYS)) |
Eric Dumazet | a2a385d | 2012-05-16 23:15:34 +0000 | [diff] [blame] | 1149 | return true; |
Eric Dumazet | bc2ce89 | 2010-12-16 14:08:34 -0800 | [diff] [blame] | 1150 | /* |
| 1151 | * Some OSes send SYN and SYNACK messages with tsval=0 tsecr=0, |
| 1152 | * then following tcp messages have valid values. Ignore 0 value, |
| 1153 | * or else 'negative' tsval might forbid us to accept their packets. |
| 1154 | */ |
| 1155 | if (!rx_opt->ts_recent) |
Eric Dumazet | a2a385d | 2012-05-16 23:15:34 +0000 | [diff] [blame] | 1156 | return true; |
| 1157 | return false; |
Ilpo Järvinen | c887e6d | 2009-03-14 14:23:03 +0000 | [diff] [blame] | 1158 | } |
| 1159 | |
Eric Dumazet | a2a385d | 2012-05-16 23:15:34 +0000 | [diff] [blame] | 1160 | static inline bool tcp_paws_reject(const struct tcp_options_received *rx_opt, |
| 1161 | int rst) |
Ilpo Järvinen | c887e6d | 2009-03-14 14:23:03 +0000 | [diff] [blame] | 1162 | { |
| 1163 | if (tcp_paws_check(rx_opt, 0)) |
Eric Dumazet | a2a385d | 2012-05-16 23:15:34 +0000 | [diff] [blame] | 1164 | return false; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1165 | |
| 1166 | /* RST segments are not recommended to carry timestamp, |
| 1167 | and, if they do, it is recommended to ignore PAWS because |
| 1168 | "their cleanup function should take precedence over timestamps." |
| 1169 | Certainly, it is mistake. It is necessary to understand the reasons |
| 1170 | of this constraint to relax it: if peer reboots, clock may go |
| 1171 | out-of-sync and half-open connections will not be reset. |
| 1172 | Actually, the problem would be not existing if all |
| 1173 | the implementations followed draft about maintaining clock |
| 1174 | via reboots. Linux-2.2 DOES NOT! |
| 1175 | |
| 1176 | However, we can relax time bounds for RST segments to MSL. |
| 1177 | */ |
James Morris | 9d729f7 | 2007-03-04 16:12:44 -0800 | [diff] [blame] | 1178 | if (rst && get_seconds() >= rx_opt->ts_recent_stamp + TCP_PAWS_MSL) |
Eric Dumazet | a2a385d | 2012-05-16 23:15:34 +0000 | [diff] [blame] | 1179 | return false; |
| 1180 | return true; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1181 | } |
| 1182 | |
Pavel Emelyanov | a9c19329 | 2008-07-16 20:21:42 -0700 | [diff] [blame] | 1183 | static inline void tcp_mib_init(struct net *net) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1184 | { |
| 1185 | /* See RFC 2012 */ |
Pavel Emelyanov | cf1100a | 2008-07-16 20:27:38 -0700 | [diff] [blame] | 1186 | TCP_ADD_STATS_USER(net, TCP_MIB_RTOALGORITHM, 1); |
| 1187 | TCP_ADD_STATS_USER(net, TCP_MIB_RTOMIN, TCP_RTO_MIN*1000/HZ); |
| 1188 | TCP_ADD_STATS_USER(net, TCP_MIB_RTOMAX, TCP_RTO_MAX*1000/HZ); |
| 1189 | TCP_ADD_STATS_USER(net, TCP_MIB_MAXCONN, -1); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1190 | } |
| 1191 | |
Ilpo Järvinen | 5af4ec2 | 2007-09-20 11:30:48 -0700 | [diff] [blame] | 1192 | /* from STCP */ |
Ilpo Järvinen | ef9da47 | 2008-09-20 21:25:15 -0700 | [diff] [blame] | 1193 | static inline void tcp_clear_retrans_hints_partial(struct tcp_sock *tp) |
David S. Miller | 0800f17 | 2007-09-20 11:40:37 -0700 | [diff] [blame] | 1194 | { |
Stephen Hemminger | 6a438bb | 2005-11-10 17:14:59 -0800 | [diff] [blame] | 1195 | tp->lost_skb_hint = NULL; |
Ilpo Järvinen | ef9da47 | 2008-09-20 21:25:15 -0700 | [diff] [blame] | 1196 | } |
| 1197 | |
| 1198 | static inline void tcp_clear_all_retrans_hints(struct tcp_sock *tp) |
| 1199 | { |
| 1200 | tcp_clear_retrans_hints_partial(tp); |
Stephen Hemminger | 6a438bb | 2005-11-10 17:14:59 -0800 | [diff] [blame] | 1201 | tp->retransmit_skb_hint = NULL; |
Ilpo Järvinen | b768920 | 2007-09-20 11:37:19 -0700 | [diff] [blame] | 1202 | } |
| 1203 | |
YOSHIFUJI Hideaki | cfb6eeb | 2006-11-14 19:07:45 -0800 | [diff] [blame] | 1204 | /* MD5 Signature */ |
| 1205 | struct crypto_hash; |
| 1206 | |
Eric Dumazet | a915da9b | 2012-01-31 05:18:33 +0000 | [diff] [blame] | 1207 | union tcp_md5_addr { |
| 1208 | struct in_addr a4; |
| 1209 | #if IS_ENABLED(CONFIG_IPV6) |
| 1210 | struct in6_addr a6; |
| 1211 | #endif |
| 1212 | }; |
| 1213 | |
YOSHIFUJI Hideaki | cfb6eeb | 2006-11-14 19:07:45 -0800 | [diff] [blame] | 1214 | /* - key database */ |
| 1215 | struct tcp_md5sig_key { |
Eric Dumazet | a915da9b | 2012-01-31 05:18:33 +0000 | [diff] [blame] | 1216 | struct hlist_node node; |
YOSHIFUJI Hideaki | cfb6eeb | 2006-11-14 19:07:45 -0800 | [diff] [blame] | 1217 | u8 keylen; |
Eric Dumazet | a915da9b | 2012-01-31 05:18:33 +0000 | [diff] [blame] | 1218 | u8 family; /* AF_INET or AF_INET6 */ |
| 1219 | union tcp_md5_addr addr; |
| 1220 | u8 key[TCP_MD5SIG_MAXKEYLEN]; |
| 1221 | struct rcu_head rcu; |
YOSHIFUJI Hideaki | cfb6eeb | 2006-11-14 19:07:45 -0800 | [diff] [blame] | 1222 | }; |
| 1223 | |
| 1224 | /* - sock block */ |
| 1225 | struct tcp_md5sig_info { |
Eric Dumazet | a915da9b | 2012-01-31 05:18:33 +0000 | [diff] [blame] | 1226 | struct hlist_head head; |
Eric Dumazet | a8afca0 | 2012-01-31 18:45:40 +0000 | [diff] [blame] | 1227 | struct rcu_head rcu; |
YOSHIFUJI Hideaki | cfb6eeb | 2006-11-14 19:07:45 -0800 | [diff] [blame] | 1228 | }; |
| 1229 | |
| 1230 | /* - pseudo header */ |
| 1231 | struct tcp4_pseudohdr { |
| 1232 | __be32 saddr; |
| 1233 | __be32 daddr; |
| 1234 | __u8 pad; |
| 1235 | __u8 protocol; |
| 1236 | __be16 len; |
| 1237 | }; |
| 1238 | |
| 1239 | struct tcp6_pseudohdr { |
| 1240 | struct in6_addr saddr; |
| 1241 | struct in6_addr daddr; |
| 1242 | __be32 len; |
| 1243 | __be32 protocol; /* including padding */ |
| 1244 | }; |
| 1245 | |
| 1246 | union tcp_md5sum_block { |
| 1247 | struct tcp4_pseudohdr ip4; |
Eric Dumazet | dfd56b8 | 2011-12-10 09:48:31 +0000 | [diff] [blame] | 1248 | #if IS_ENABLED(CONFIG_IPV6) |
YOSHIFUJI Hideaki | cfb6eeb | 2006-11-14 19:07:45 -0800 | [diff] [blame] | 1249 | struct tcp6_pseudohdr ip6; |
| 1250 | #endif |
| 1251 | }; |
| 1252 | |
| 1253 | /* - pool: digest algorithm, hash description and scratch buffer */ |
| 1254 | struct tcp_md5sig_pool { |
| 1255 | struct hash_desc md5_desc; |
| 1256 | union tcp_md5sum_block md5_blk; |
| 1257 | }; |
| 1258 | |
YOSHIFUJI Hideaki | cfb6eeb | 2006-11-14 19:07:45 -0800 | [diff] [blame] | 1259 | /* - functions */ |
Joe Perches | 5c9f302 | 2013-09-23 11:33:32 -0700 | [diff] [blame] | 1260 | int tcp_v4_md5_hash_skb(char *md5_hash, struct tcp_md5sig_key *key, |
| 1261 | const struct sock *sk, const struct request_sock *req, |
| 1262 | const struct sk_buff *skb); |
| 1263 | int tcp_md5_do_add(struct sock *sk, const union tcp_md5_addr *addr, |
| 1264 | int family, const u8 *newkey, u8 newkeylen, gfp_t gfp); |
| 1265 | int tcp_md5_do_del(struct sock *sk, const union tcp_md5_addr *addr, |
| 1266 | int family); |
| 1267 | struct tcp_md5sig_key *tcp_v4_md5_lookup(struct sock *sk, |
Eric Dumazet | a915da9b | 2012-01-31 05:18:33 +0000 | [diff] [blame] | 1268 | struct sock *addr_sk); |
YOSHIFUJI Hideaki | cfb6eeb | 2006-11-14 19:07:45 -0800 | [diff] [blame] | 1269 | |
YOSHIFUJI Hideaki | 9501f97 | 2008-04-18 12:45:16 +0900 | [diff] [blame] | 1270 | #ifdef CONFIG_TCP_MD5SIG |
Joe Perches | 5c9f302 | 2013-09-23 11:33:32 -0700 | [diff] [blame] | 1271 | struct tcp_md5sig_key *tcp_md5_do_lookup(struct sock *sk, |
| 1272 | const union tcp_md5_addr *addr, |
| 1273 | int family); |
Eric Dumazet | a915da9b | 2012-01-31 05:18:33 +0000 | [diff] [blame] | 1274 | #define tcp_twsk_md5_key(twsk) ((twsk)->tw_md5_key) |
YOSHIFUJI Hideaki | 9501f97 | 2008-04-18 12:45:16 +0900 | [diff] [blame] | 1275 | #else |
Eric Dumazet | a915da9b | 2012-01-31 05:18:33 +0000 | [diff] [blame] | 1276 | static inline struct tcp_md5sig_key *tcp_md5_do_lookup(struct sock *sk, |
| 1277 | const union tcp_md5_addr *addr, |
| 1278 | int family) |
| 1279 | { |
| 1280 | return NULL; |
| 1281 | } |
YOSHIFUJI Hideaki | 9501f97 | 2008-04-18 12:45:16 +0900 | [diff] [blame] | 1282 | #define tcp_twsk_md5_key(twsk) NULL |
| 1283 | #endif |
| 1284 | |
Joe Perches | 5c9f302 | 2013-09-23 11:33:32 -0700 | [diff] [blame] | 1285 | bool tcp_alloc_md5sig_pool(void); |
YOSHIFUJI Hideaki | cfb6eeb | 2006-11-14 19:07:45 -0800 | [diff] [blame] | 1286 | |
Joe Perches | 5c9f302 | 2013-09-23 11:33:32 -0700 | [diff] [blame] | 1287 | struct tcp_md5sig_pool *tcp_get_md5sig_pool(void); |
Eric Dumazet | 71cea17 | 2013-05-20 06:52:26 +0000 | [diff] [blame] | 1288 | static inline void tcp_put_md5sig_pool(void) |
| 1289 | { |
| 1290 | local_bh_enable(); |
| 1291 | } |
Eric Dumazet | 35790c0 | 2010-05-16 00:34:04 -0700 | [diff] [blame] | 1292 | |
Joe Perches | 5c9f302 | 2013-09-23 11:33:32 -0700 | [diff] [blame] | 1293 | int tcp_md5_hash_header(struct tcp_md5sig_pool *, const struct tcphdr *); |
| 1294 | int tcp_md5_hash_skb_data(struct tcp_md5sig_pool *, const struct sk_buff *, |
| 1295 | unsigned int header_len); |
| 1296 | int tcp_md5_hash_key(struct tcp_md5sig_pool *hp, |
| 1297 | const struct tcp_md5sig_key *key); |
YOSHIFUJI Hideaki | cfb6eeb | 2006-11-14 19:07:45 -0800 | [diff] [blame] | 1298 | |
Jerry Chu | 1046716 | 2012-08-31 12:29:11 +0000 | [diff] [blame] | 1299 | /* From tcp_fastopen.c */ |
Joe Perches | 5c9f302 | 2013-09-23 11:33:32 -0700 | [diff] [blame] | 1300 | void tcp_fastopen_cache_get(struct sock *sk, u16 *mss, |
| 1301 | struct tcp_fastopen_cookie *cookie, int *syn_loss, |
| 1302 | unsigned long *last_syn_loss); |
| 1303 | void tcp_fastopen_cache_set(struct sock *sk, u16 mss, |
| 1304 | struct tcp_fastopen_cookie *cookie, bool syn_lost); |
Yuchung Cheng | 783237e | 2012-07-19 06:43:07 +0000 | [diff] [blame] | 1305 | struct tcp_fastopen_request { |
| 1306 | /* Fast Open cookie. Size 0 means a cookie request */ |
| 1307 | struct tcp_fastopen_cookie cookie; |
| 1308 | struct msghdr *data; /* data in MSG_FASTOPEN */ |
| 1309 | u16 copied; /* queued in tcp_connect() */ |
| 1310 | }; |
Yuchung Cheng | 783237e | 2012-07-19 06:43:07 +0000 | [diff] [blame] | 1311 | void tcp_free_fastopen_req(struct tcp_sock *tp); |
| 1312 | |
Jerry Chu | 1046716 | 2012-08-31 12:29:11 +0000 | [diff] [blame] | 1313 | extern struct tcp_fastopen_context __rcu *tcp_fastopen_ctx; |
| 1314 | int tcp_fastopen_reset_cipher(void *key, unsigned int len); |
Joe Perches | 5c9f302 | 2013-09-23 11:33:32 -0700 | [diff] [blame] | 1315 | void tcp_fastopen_cookie_gen(__be32 src, __be32 dst, |
| 1316 | struct tcp_fastopen_cookie *foc); |
Hannes Frederic Sowa | 222e83d | 2013-10-19 21:48:58 +0200 | [diff] [blame] | 1317 | void tcp_fastopen_init_key_once(bool publish); |
Jerry Chu | 1046716 | 2012-08-31 12:29:11 +0000 | [diff] [blame] | 1318 | #define TCP_FASTOPEN_KEY_LENGTH 16 |
| 1319 | |
| 1320 | /* Fastopen key context */ |
| 1321 | struct tcp_fastopen_context { |
Eric Dumazet | 7ae8639 | 2013-06-25 01:21:06 -0700 | [diff] [blame] | 1322 | struct crypto_cipher *tfm; |
| 1323 | __u8 key[TCP_FASTOPEN_KEY_LENGTH]; |
| 1324 | struct rcu_head rcu; |
Jerry Chu | 1046716 | 2012-08-31 12:29:11 +0000 | [diff] [blame] | 1325 | }; |
| 1326 | |
David S. Miller | fe067e8 | 2007-03-07 12:12:44 -0800 | [diff] [blame] | 1327 | /* write queue abstraction */ |
| 1328 | static inline void tcp_write_queue_purge(struct sock *sk) |
| 1329 | { |
| 1330 | struct sk_buff *skb; |
| 1331 | |
| 1332 | while ((skb = __skb_dequeue(&sk->sk_write_queue)) != NULL) |
Hideo Aoki | 3ab224b | 2007-12-31 00:11:19 -0800 | [diff] [blame] | 1333 | sk_wmem_free_skb(sk, skb); |
| 1334 | sk_mem_reclaim(sk); |
Ilpo Järvinen | 8818a9d | 2009-12-02 22:24:02 -0800 | [diff] [blame] | 1335 | tcp_clear_all_retrans_hints(tcp_sk(sk)); |
David S. Miller | fe067e8 | 2007-03-07 12:12:44 -0800 | [diff] [blame] | 1336 | } |
| 1337 | |
Eric Dumazet | cf533ea | 2011-10-21 05:22:42 -0400 | [diff] [blame] | 1338 | static inline struct sk_buff *tcp_write_queue_head(const struct sock *sk) |
David S. Miller | fe067e8 | 2007-03-07 12:12:44 -0800 | [diff] [blame] | 1339 | { |
David S. Miller | cd07a8e | 2008-09-23 00:50:13 -0700 | [diff] [blame] | 1340 | return skb_peek(&sk->sk_write_queue); |
David S. Miller | fe067e8 | 2007-03-07 12:12:44 -0800 | [diff] [blame] | 1341 | } |
| 1342 | |
Eric Dumazet | cf533ea | 2011-10-21 05:22:42 -0400 | [diff] [blame] | 1343 | static inline struct sk_buff *tcp_write_queue_tail(const struct sock *sk) |
David S. Miller | fe067e8 | 2007-03-07 12:12:44 -0800 | [diff] [blame] | 1344 | { |
David S. Miller | cd07a8e | 2008-09-23 00:50:13 -0700 | [diff] [blame] | 1345 | return skb_peek_tail(&sk->sk_write_queue); |
David S. Miller | fe067e8 | 2007-03-07 12:12:44 -0800 | [diff] [blame] | 1346 | } |
| 1347 | |
Eric Dumazet | cf533ea | 2011-10-21 05:22:42 -0400 | [diff] [blame] | 1348 | static inline struct sk_buff *tcp_write_queue_next(const struct sock *sk, |
| 1349 | const struct sk_buff *skb) |
David S. Miller | fe067e8 | 2007-03-07 12:12:44 -0800 | [diff] [blame] | 1350 | { |
David S. Miller | cd07a8e | 2008-09-23 00:50:13 -0700 | [diff] [blame] | 1351 | return skb_queue_next(&sk->sk_write_queue, skb); |
David S. Miller | fe067e8 | 2007-03-07 12:12:44 -0800 | [diff] [blame] | 1352 | } |
| 1353 | |
Eric Dumazet | cf533ea | 2011-10-21 05:22:42 -0400 | [diff] [blame] | 1354 | static inline struct sk_buff *tcp_write_queue_prev(const struct sock *sk, |
| 1355 | const struct sk_buff *skb) |
Ilpo Järvinen | 832d11c | 2008-11-24 21:20:15 -0800 | [diff] [blame] | 1356 | { |
| 1357 | return skb_queue_prev(&sk->sk_write_queue, skb); |
| 1358 | } |
| 1359 | |
David S. Miller | fe067e8 | 2007-03-07 12:12:44 -0800 | [diff] [blame] | 1360 | #define tcp_for_write_queue(skb, sk) \ |
David S. Miller | cd07a8e | 2008-09-23 00:50:13 -0700 | [diff] [blame] | 1361 | skb_queue_walk(&(sk)->sk_write_queue, skb) |
David S. Miller | fe067e8 | 2007-03-07 12:12:44 -0800 | [diff] [blame] | 1362 | |
| 1363 | #define tcp_for_write_queue_from(skb, sk) \ |
David S. Miller | cd07a8e | 2008-09-23 00:50:13 -0700 | [diff] [blame] | 1364 | skb_queue_walk_from(&(sk)->sk_write_queue, skb) |
David S. Miller | fe067e8 | 2007-03-07 12:12:44 -0800 | [diff] [blame] | 1365 | |
Ilpo Järvinen | 234b686 | 2007-12-02 00:48:02 +0200 | [diff] [blame] | 1366 | #define tcp_for_write_queue_from_safe(skb, tmp, sk) \ |
David S. Miller | cd07a8e | 2008-09-23 00:50:13 -0700 | [diff] [blame] | 1367 | skb_queue_walk_from_safe(&(sk)->sk_write_queue, skb, tmp) |
Ilpo Järvinen | 234b686 | 2007-12-02 00:48:02 +0200 | [diff] [blame] | 1368 | |
Eric Dumazet | cf533ea | 2011-10-21 05:22:42 -0400 | [diff] [blame] | 1369 | static inline struct sk_buff *tcp_send_head(const struct sock *sk) |
David S. Miller | fe067e8 | 2007-03-07 12:12:44 -0800 | [diff] [blame] | 1370 | { |
| 1371 | return sk->sk_send_head; |
| 1372 | } |
| 1373 | |
David S. Miller | cd07a8e | 2008-09-23 00:50:13 -0700 | [diff] [blame] | 1374 | static inline bool tcp_skb_is_last(const struct sock *sk, |
| 1375 | const struct sk_buff *skb) |
| 1376 | { |
| 1377 | return skb_queue_is_last(&sk->sk_write_queue, skb); |
| 1378 | } |
| 1379 | |
Eric Dumazet | cf533ea | 2011-10-21 05:22:42 -0400 | [diff] [blame] | 1380 | static inline void tcp_advance_send_head(struct sock *sk, const struct sk_buff *skb) |
David S. Miller | fe067e8 | 2007-03-07 12:12:44 -0800 | [diff] [blame] | 1381 | { |
David S. Miller | cd07a8e | 2008-09-23 00:50:13 -0700 | [diff] [blame] | 1382 | if (tcp_skb_is_last(sk, skb)) |
David S. Miller | fe067e8 | 2007-03-07 12:12:44 -0800 | [diff] [blame] | 1383 | sk->sk_send_head = NULL; |
David S. Miller | cd07a8e | 2008-09-23 00:50:13 -0700 | [diff] [blame] | 1384 | else |
| 1385 | sk->sk_send_head = tcp_write_queue_next(sk, skb); |
David S. Miller | fe067e8 | 2007-03-07 12:12:44 -0800 | [diff] [blame] | 1386 | } |
| 1387 | |
| 1388 | static inline void tcp_check_send_head(struct sock *sk, struct sk_buff *skb_unlinked) |
| 1389 | { |
| 1390 | if (sk->sk_send_head == skb_unlinked) |
| 1391 | sk->sk_send_head = NULL; |
| 1392 | } |
| 1393 | |
| 1394 | static inline void tcp_init_send_head(struct sock *sk) |
| 1395 | { |
| 1396 | sk->sk_send_head = NULL; |
| 1397 | } |
| 1398 | |
| 1399 | static inline void __tcp_add_write_queue_tail(struct sock *sk, struct sk_buff *skb) |
| 1400 | { |
| 1401 | __skb_queue_tail(&sk->sk_write_queue, skb); |
| 1402 | } |
| 1403 | |
| 1404 | static inline void tcp_add_write_queue_tail(struct sock *sk, struct sk_buff *skb) |
| 1405 | { |
| 1406 | __tcp_add_write_queue_tail(sk, skb); |
| 1407 | |
| 1408 | /* Queue it, remembering where we must start sending. */ |
Ilpo Järvinen | 6859d49 | 2007-12-02 00:48:06 +0200 | [diff] [blame] | 1409 | if (sk->sk_send_head == NULL) { |
David S. Miller | fe067e8 | 2007-03-07 12:12:44 -0800 | [diff] [blame] | 1410 | sk->sk_send_head = skb; |
Ilpo Järvinen | 6859d49 | 2007-12-02 00:48:06 +0200 | [diff] [blame] | 1411 | |
| 1412 | if (tcp_sk(sk)->highest_sack == NULL) |
| 1413 | tcp_sk(sk)->highest_sack = skb; |
| 1414 | } |
David S. Miller | fe067e8 | 2007-03-07 12:12:44 -0800 | [diff] [blame] | 1415 | } |
| 1416 | |
| 1417 | static inline void __tcp_add_write_queue_head(struct sock *sk, struct sk_buff *skb) |
| 1418 | { |
| 1419 | __skb_queue_head(&sk->sk_write_queue, skb); |
| 1420 | } |
| 1421 | |
| 1422 | /* Insert buff after skb on the write queue of sk. */ |
| 1423 | static inline void tcp_insert_write_queue_after(struct sk_buff *skb, |
| 1424 | struct sk_buff *buff, |
| 1425 | struct sock *sk) |
| 1426 | { |
Gerrit Renker | 7de6c03 | 2008-04-14 00:05:09 -0700 | [diff] [blame] | 1427 | __skb_queue_after(&sk->sk_write_queue, skb, buff); |
David S. Miller | fe067e8 | 2007-03-07 12:12:44 -0800 | [diff] [blame] | 1428 | } |
| 1429 | |
David S. Miller | 43f59c8 | 2008-09-21 21:28:51 -0700 | [diff] [blame] | 1430 | /* Insert new before skb on the write queue of sk. */ |
David S. Miller | fe067e8 | 2007-03-07 12:12:44 -0800 | [diff] [blame] | 1431 | static inline void tcp_insert_write_queue_before(struct sk_buff *new, |
| 1432 | struct sk_buff *skb, |
| 1433 | struct sock *sk) |
| 1434 | { |
David S. Miller | 43f59c8 | 2008-09-21 21:28:51 -0700 | [diff] [blame] | 1435 | __skb_queue_before(&sk->sk_write_queue, skb, new); |
Ilpo Järvinen | 6e42141 | 2007-11-19 23:24:09 -0800 | [diff] [blame] | 1436 | |
| 1437 | if (sk->sk_send_head == skb) |
| 1438 | sk->sk_send_head = new; |
David S. Miller | fe067e8 | 2007-03-07 12:12:44 -0800 | [diff] [blame] | 1439 | } |
| 1440 | |
| 1441 | static inline void tcp_unlink_write_queue(struct sk_buff *skb, struct sock *sk) |
| 1442 | { |
| 1443 | __skb_unlink(skb, &sk->sk_write_queue); |
| 1444 | } |
| 1445 | |
Eric Dumazet | a2a385d | 2012-05-16 23:15:34 +0000 | [diff] [blame] | 1446 | static inline bool tcp_write_queue_empty(struct sock *sk) |
David S. Miller | fe067e8 | 2007-03-07 12:12:44 -0800 | [diff] [blame] | 1447 | { |
| 1448 | return skb_queue_empty(&sk->sk_write_queue); |
| 1449 | } |
| 1450 | |
Krishna Kumar | 12d50c4 | 2009-12-08 22:26:13 +0000 | [diff] [blame] | 1451 | static inline void tcp_push_pending_frames(struct sock *sk) |
| 1452 | { |
| 1453 | if (tcp_send_head(sk)) { |
| 1454 | struct tcp_sock *tp = tcp_sk(sk); |
| 1455 | |
| 1456 | __tcp_push_pending_frames(sk, tcp_current_mss(sk), tp->nonagle); |
| 1457 | } |
| 1458 | } |
| 1459 | |
Neal Cardwell | ecb9719 | 2012-02-27 17:52:52 -0500 | [diff] [blame] | 1460 | /* Start sequence of the skb just after the highest skb with SACKed |
| 1461 | * bit, valid only if sacked_out > 0 or when the caller has ensured |
| 1462 | * validity by itself. |
Ilpo Järvinen | a47e5a9 | 2007-11-15 19:41:46 -0800 | [diff] [blame] | 1463 | */ |
| 1464 | static inline u32 tcp_highest_sack_seq(struct tcp_sock *tp) |
| 1465 | { |
| 1466 | if (!tp->sacked_out) |
| 1467 | return tp->snd_una; |
Ilpo Järvinen | 6859d49 | 2007-12-02 00:48:06 +0200 | [diff] [blame] | 1468 | |
| 1469 | if (tp->highest_sack == NULL) |
| 1470 | return tp->snd_nxt; |
| 1471 | |
Ilpo Järvinen | a47e5a9 | 2007-11-15 19:41:46 -0800 | [diff] [blame] | 1472 | return TCP_SKB_CB(tp->highest_sack)->seq; |
| 1473 | } |
| 1474 | |
Ilpo Järvinen | 6859d49 | 2007-12-02 00:48:06 +0200 | [diff] [blame] | 1475 | static inline void tcp_advance_highest_sack(struct sock *sk, struct sk_buff *skb) |
| 1476 | { |
| 1477 | tcp_sk(sk)->highest_sack = tcp_skb_is_last(sk, skb) ? NULL : |
| 1478 | tcp_write_queue_next(sk, skb); |
| 1479 | } |
| 1480 | |
| 1481 | static inline struct sk_buff *tcp_highest_sack(struct sock *sk) |
| 1482 | { |
| 1483 | return tcp_sk(sk)->highest_sack; |
| 1484 | } |
| 1485 | |
| 1486 | static inline void tcp_highest_sack_reset(struct sock *sk) |
| 1487 | { |
| 1488 | tcp_sk(sk)->highest_sack = tcp_write_queue_head(sk); |
| 1489 | } |
| 1490 | |
| 1491 | /* Called when old skb is about to be deleted (to be combined with new skb) */ |
| 1492 | static inline void tcp_highest_sack_combine(struct sock *sk, |
| 1493 | struct sk_buff *old, |
| 1494 | struct sk_buff *new) |
| 1495 | { |
| 1496 | if (tcp_sk(sk)->sacked_out && (old == tcp_sk(sk)->highest_sack)) |
| 1497 | tcp_sk(sk)->highest_sack = new; |
| 1498 | } |
| 1499 | |
Andreas Petlund | 5aa4b32 | 2010-02-18 02:45:45 +0000 | [diff] [blame] | 1500 | /* Determines whether this is a thin stream (which may suffer from |
| 1501 | * increased latency). Used to trigger latency-reducing mechanisms. |
| 1502 | */ |
Eric Dumazet | a2a385d | 2012-05-16 23:15:34 +0000 | [diff] [blame] | 1503 | static inline bool tcp_stream_is_thin(struct tcp_sock *tp) |
Andreas Petlund | 5aa4b32 | 2010-02-18 02:45:45 +0000 | [diff] [blame] | 1504 | { |
| 1505 | return tp->packets_out < 4 && !tcp_in_initial_slowstart(tp); |
| 1506 | } |
| 1507 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1508 | /* /proc */ |
| 1509 | enum tcp_seq_states { |
| 1510 | TCP_SEQ_STATE_LISTENING, |
| 1511 | TCP_SEQ_STATE_OPENREQ, |
| 1512 | TCP_SEQ_STATE_ESTABLISHED, |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1513 | }; |
| 1514 | |
Arjan van de Ven | 73cb88e | 2011-10-30 06:46:30 +0000 | [diff] [blame] | 1515 | int tcp_seq_open(struct inode *inode, struct file *file); |
| 1516 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1517 | struct tcp_seq_afinfo { |
Arjan van de Ven | 73cb88e | 2011-10-30 06:46:30 +0000 | [diff] [blame] | 1518 | char *name; |
| 1519 | sa_family_t family; |
| 1520 | const struct file_operations *seq_fops; |
| 1521 | struct seq_operations seq_ops; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1522 | }; |
| 1523 | |
| 1524 | struct tcp_iter_state { |
Denis V. Lunev | a4146b1 | 2008-04-13 22:11:14 -0700 | [diff] [blame] | 1525 | struct seq_net_private p; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1526 | sa_family_t family; |
| 1527 | enum tcp_seq_states state; |
| 1528 | struct sock *syn_wait_sk; |
Eric W. Biederman | a7cb5a4 | 2012-05-24 01:10:10 -0600 | [diff] [blame] | 1529 | int bucket, offset, sbucket, num; |
| 1530 | kuid_t uid; |
Tom Herbert | a8b690f | 2010-06-07 00:43:42 -0700 | [diff] [blame] | 1531 | loff_t last_pos; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1532 | }; |
| 1533 | |
Joe Perches | 5c9f302 | 2013-09-23 11:33:32 -0700 | [diff] [blame] | 1534 | int tcp_proc_register(struct net *net, struct tcp_seq_afinfo *afinfo); |
| 1535 | void tcp_proc_unregister(struct net *net, struct tcp_seq_afinfo *afinfo); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1536 | |
Arnaldo Carvalho de Melo | 2038073 | 2005-08-16 02:18:02 -0300 | [diff] [blame] | 1537 | extern struct request_sock_ops tcp_request_sock_ops; |
Glenn Griffin | c6aefaf | 2008-02-07 21:49:26 -0800 | [diff] [blame] | 1538 | extern struct request_sock_ops tcp6_request_sock_ops; |
Arnaldo Carvalho de Melo | 2038073 | 2005-08-16 02:18:02 -0300 | [diff] [blame] | 1539 | |
Joe Perches | 5c9f302 | 2013-09-23 11:33:32 -0700 | [diff] [blame] | 1540 | void tcp_v4_destroy_sock(struct sock *sk); |
Arnaldo Carvalho de Melo | 2038073 | 2005-08-16 02:18:02 -0300 | [diff] [blame] | 1541 | |
Eric Dumazet | 28be6e0 | 2013-10-18 10:36:17 -0700 | [diff] [blame] | 1542 | struct sk_buff *tcp_gso_segment(struct sk_buff *skb, |
Joe Perches | 5c9f302 | 2013-09-23 11:33:32 -0700 | [diff] [blame] | 1543 | netdev_features_t features); |
| 1544 | struct sk_buff **tcp_gro_receive(struct sk_buff **head, struct sk_buff *skb); |
| 1545 | int tcp_gro_complete(struct sk_buff *skb); |
Daniel Borkmann | 28850dc | 2013-06-07 05:11:46 +0000 | [diff] [blame] | 1546 | |
Joe Perches | 5c9f302 | 2013-09-23 11:33:32 -0700 | [diff] [blame] | 1547 | void __tcp_v4_send_check(struct sk_buff *skb, __be32 saddr, __be32 daddr); |
Herbert Xu | f4c50d9 | 2006-06-22 03:02:40 -0700 | [diff] [blame] | 1548 | |
Eric Dumazet | c9bee3b7 | 2013-07-22 20:27:07 -0700 | [diff] [blame] | 1549 | static inline u32 tcp_notsent_lowat(const struct tcp_sock *tp) |
| 1550 | { |
| 1551 | return tp->notsent_lowat ?: sysctl_tcp_notsent_lowat; |
| 1552 | } |
| 1553 | |
| 1554 | static inline bool tcp_stream_memory_free(const struct sock *sk) |
| 1555 | { |
| 1556 | const struct tcp_sock *tp = tcp_sk(sk); |
| 1557 | u32 notsent_bytes = tp->write_seq - tp->snd_nxt; |
| 1558 | |
| 1559 | return notsent_bytes < tcp_notsent_lowat(tp); |
| 1560 | } |
| 1561 | |
Arnaldo Carvalho de Melo | 2038073 | 2005-08-16 02:18:02 -0300 | [diff] [blame] | 1562 | #ifdef CONFIG_PROC_FS |
Joe Perches | 5c9f302 | 2013-09-23 11:33:32 -0700 | [diff] [blame] | 1563 | int tcp4_proc_init(void); |
| 1564 | void tcp4_proc_exit(void); |
Arnaldo Carvalho de Melo | 2038073 | 2005-08-16 02:18:02 -0300 | [diff] [blame] | 1565 | #endif |
| 1566 | |
YOSHIFUJI Hideaki | cfb6eeb | 2006-11-14 19:07:45 -0800 | [diff] [blame] | 1567 | /* TCP af-specific functions */ |
| 1568 | struct tcp_sock_af_ops { |
| 1569 | #ifdef CONFIG_TCP_MD5SIG |
| 1570 | struct tcp_md5sig_key *(*md5_lookup) (struct sock *sk, |
| 1571 | struct sock *addr_sk); |
| 1572 | int (*calc_md5_hash) (char *location, |
| 1573 | struct tcp_md5sig_key *md5, |
Eric Dumazet | 318cf7a | 2011-10-24 02:46:04 -0400 | [diff] [blame] | 1574 | const struct sock *sk, |
| 1575 | const struct request_sock *req, |
| 1576 | const struct sk_buff *skb); |
YOSHIFUJI Hideaki | cfb6eeb | 2006-11-14 19:07:45 -0800 | [diff] [blame] | 1577 | int (*md5_parse) (struct sock *sk, |
| 1578 | char __user *optval, |
| 1579 | int optlen); |
| 1580 | #endif |
| 1581 | }; |
| 1582 | |
| 1583 | struct tcp_request_sock_ops { |
| 1584 | #ifdef CONFIG_TCP_MD5SIG |
| 1585 | struct tcp_md5sig_key *(*md5_lookup) (struct sock *sk, |
| 1586 | struct request_sock *req); |
John Dykstra | e3afe7b | 2009-07-16 05:04:51 +0000 | [diff] [blame] | 1587 | int (*calc_md5_hash) (char *location, |
| 1588 | struct tcp_md5sig_key *md5, |
Eric Dumazet | 318cf7a | 2011-10-24 02:46:04 -0400 | [diff] [blame] | 1589 | const struct sock *sk, |
| 1590 | const struct request_sock *req, |
| 1591 | const struct sk_buff *skb); |
YOSHIFUJI Hideaki | cfb6eeb | 2006-11-14 19:07:45 -0800 | [diff] [blame] | 1592 | #endif |
| 1593 | }; |
| 1594 | |
Joe Perches | 5c9f302 | 2013-09-23 11:33:32 -0700 | [diff] [blame] | 1595 | int tcpv4_offload_init(void); |
Daniel Borkmann | 28850dc | 2013-06-07 05:11:46 +0000 | [diff] [blame] | 1596 | |
Joe Perches | 5c9f302 | 2013-09-23 11:33:32 -0700 | [diff] [blame] | 1597 | void tcp_v4_init(void); |
| 1598 | void tcp_init(void); |
Arnaldo Carvalho de Melo | 2038073 | 2005-08-16 02:18:02 -0300 | [diff] [blame] | 1599 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1600 | #endif /* _TCP_H */ |