kernel: Make SMP support default (and non-optional).
[dragonfly.git] / sys / netinet / tcp_subr.c
CommitLineData
984263bc 1/*
66d6c637
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2 * Copyright (c) 2003, 2004 Jeffrey M. Hsu. All rights reserved.
3 * Copyright (c) 2003, 2004 The DragonFly Project. All rights reserved.
f23061d4 4 *
66d6c637
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5 * This code is derived from software contributed to The DragonFly Project
6 * by Jeffrey M. Hsu.
f23061d4 7 *
66d6c637
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8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the name of The DragonFly Project nor the names of its
17 * contributors may be used to endorse or promote products derived
18 * from this software without specific, prior written permission.
f23061d4 19 *
66d6c637
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20 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
23 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
24 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
25 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
26 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
27 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
28 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
29 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
30 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
66d6c637 34/*
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35 * Copyright (c) 1982, 1986, 1988, 1990, 1993, 1995
36 * The Regents of the University of California. All rights reserved.
37 *
38 * Redistribution and use in source and binary forms, with or without
39 * modification, are permitted provided that the following conditions
40 * are met:
41 * 1. Redistributions of source code must retain the above copyright
42 * notice, this list of conditions and the following disclaimer.
43 * 2. Redistributions in binary form must reproduce the above copyright
44 * notice, this list of conditions and the following disclaimer in the
45 * documentation and/or other materials provided with the distribution.
46 * 3. All advertising materials mentioning features or use of this software
47 * must display the following acknowledgement:
48 * This product includes software developed by the University of
49 * California, Berkeley and its contributors.
50 * 4. Neither the name of the University nor the names of its contributors
51 * may be used to endorse or promote products derived from this software
52 * without specific prior written permission.
53 *
54 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
55 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
56 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
57 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
58 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
59 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
60 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
61 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
62 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
63 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
64 * SUCH DAMAGE.
65 *
66 * @(#)tcp_subr.c 8.2 (Berkeley) 5/24/95
67 * $FreeBSD: src/sys/netinet/tcp_subr.c,v 1.73.2.31 2003/01/24 05:11:34 sam Exp $
68 */
69
70#include "opt_compat.h"
b1992928 71#include "opt_inet.h"
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72#include "opt_inet6.h"
73#include "opt_ipsec.h"
74#include "opt_tcpdebug.h"
75
76#include <sys/param.h>
77#include <sys/systm.h>
78#include <sys/callout.h>
79#include <sys/kernel.h>
80#include <sys/sysctl.h>
81#include <sys/malloc.h>
dd2b0fb4 82#include <sys/mpipe.h>
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83#include <sys/mbuf.h>
84#ifdef INET6
85#include <sys/domain.h>
86#endif
87#include <sys/proc.h>
895c1f85 88#include <sys/priv.h>
984263bc 89#include <sys/socket.h>
96c6eb29 90#include <sys/socketops.h>
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91#include <sys/socketvar.h>
92#include <sys/protosw.h>
93#include <sys/random.h>
3f9db7f8 94#include <sys/in_cksum.h>
c7afbe76 95#include <sys/ktr.h>
984263bc 96
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97#include <net/route.h>
98#include <net/if.h>
0ddb6032 99#include <net/netisr.h>
984263bc 100
707ad4ed 101#define _IP_VHL
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102#include <netinet/in.h>
103#include <netinet/in_systm.h>
104#include <netinet/ip.h>
984263bc 105#include <netinet/ip6.h>
984263bc 106#include <netinet/in_pcb.h>
984263bc 107#include <netinet6/in6_pcb.h>
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108#include <netinet/in_var.h>
109#include <netinet/ip_var.h>
984263bc 110#include <netinet6/ip6_var.h>
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111#include <netinet/ip_icmp.h>
112#ifdef INET6
113#include <netinet/icmp6.h>
114#endif
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115#include <netinet/tcp.h>
116#include <netinet/tcp_fsm.h>
117#include <netinet/tcp_seq.h>
118#include <netinet/tcp_timer.h>
a48c5dd5 119#include <netinet/tcp_timer2.h>
984263bc 120#include <netinet/tcp_var.h>
984263bc 121#include <netinet6/tcp6_var.h>
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122#include <netinet/tcpip.h>
123#ifdef TCPDEBUG
124#include <netinet/tcp_debug.h>
125#endif
126#include <netinet6/ip6protosw.h>
127
128#ifdef IPSEC
129#include <netinet6/ipsec.h>
b1992928 130#include <netproto/key/key.h>
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131#ifdef INET6
132#include <netinet6/ipsec6.h>
133#endif
707ad4ed 134#endif
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135
136#ifdef FAST_IPSEC
bf844ffa 137#include <netproto/ipsec/ipsec.h>
984263bc 138#ifdef INET6
bf844ffa 139#include <netproto/ipsec/ipsec6.h>
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140#endif
141#define IPSEC
707ad4ed 142#endif
984263bc 143
984263bc 144#include <sys/md5.h>
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145#include <machine/smp.h>
146
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147#include <sys/msgport2.h>
148#include <sys/mplock2.h>
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149#include <net/netmsg2.h>
150
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151#if !defined(KTR_TCP)
152#define KTR_TCP KTR_ALL
153#endif
c3c96e44 154/*
879a1b60 155KTR_INFO_MASTER(tcp);
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156KTR_INFO(KTR_TCP, tcp, rxmsg, 0, "tcp getmsg", 0);
157KTR_INFO(KTR_TCP, tcp, wait, 1, "tcp waitmsg", 0);
158KTR_INFO(KTR_TCP, tcp, delayed, 2, "tcp execute delayed ops", 0);
159#define logtcp(name) KTR_LOG(tcp_ ## name)
879a1b60 160*/
c7afbe76 161
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162#define TCP_IW_MAXSEGS_DFLT 4
163#define TCP_IW_CAPSEGS_DFLT 3
164
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165struct inpcbinfo tcbinfo[MAXCPU];
166struct tcpcbackqhead tcpcbackq[MAXCPU];
167
0ce0603e 168static struct lwkt_token tcp_port_token =
a3c18566 169 LWKT_TOKEN_INITIALIZER(tcp_port_token);
0ce0603e 170
707ad4ed 171int tcp_mssdflt = TCP_MSS;
f23061d4 172SYSCTL_INT(_net_inet_tcp, TCPCTL_MSSDFLT, mssdflt, CTLFLAG_RW,
707ad4ed 173 &tcp_mssdflt, 0, "Default TCP Maximum Segment Size");
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174
175#ifdef INET6
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176int tcp_v6mssdflt = TCP6_MSS;
177SYSCTL_INT(_net_inet_tcp, TCPCTL_V6MSSDFLT, v6mssdflt, CTLFLAG_RW,
178 &tcp_v6mssdflt, 0, "Default TCP Maximum Segment Size for IPv6");
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179#endif
180
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181/*
182 * Minimum MSS we accept and use. This prevents DoS attacks where
183 * we are forced to a ridiculous low MSS like 20 and send hundreds
184 * of packets instead of one. The effect scales with the available
185 * bandwidth and quickly saturates the CPU and network interface
186 * with packet generation and sending. Set to zero to disable MINMSS
187 * checking. This setting prevents us from sending too small packets.
188 */
189int tcp_minmss = TCP_MINMSS;
190SYSCTL_INT(_net_inet_tcp, OID_AUTO, minmss, CTLFLAG_RW,
191 &tcp_minmss , 0, "Minmum TCP Maximum Segment Size");
5b0b9fa5 192
984263bc 193#if 0
707ad4ed 194static int tcp_rttdflt = TCPTV_SRTTDFLT / PR_SLOWHZ;
f23061d4 195SYSCTL_INT(_net_inet_tcp, TCPCTL_RTTDFLT, rttdflt, CTLFLAG_RW,
707ad4ed 196 &tcp_rttdflt, 0, "Default maximum TCP Round Trip Time");
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197#endif
198
707ad4ed 199int tcp_do_rfc1323 = 1;
f23061d4 200SYSCTL_INT(_net_inet_tcp, TCPCTL_DO_RFC1323, rfc1323, CTLFLAG_RW,
707ad4ed 201 &tcp_do_rfc1323, 0, "Enable rfc1323 (high performance TCP) extensions");
984263bc 202
707ad4ed 203static int tcp_tcbhashsize = 0;
984263bc 204SYSCTL_INT(_net_inet_tcp, OID_AUTO, tcbhashsize, CTLFLAG_RD,
707ad4ed 205 &tcp_tcbhashsize, 0, "Size of TCP control block hashtable");
984263bc 206
707ad4ed 207static int do_tcpdrain = 1;
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208SYSCTL_INT(_net_inet_tcp, OID_AUTO, do_tcpdrain, CTLFLAG_RW, &do_tcpdrain, 0,
209 "Enable tcp_drain routine for extra help when low on mbufs");
210
707ad4ed 211static int icmp_may_rst = 1;
f23061d4 212SYSCTL_INT(_net_inet_tcp, OID_AUTO, icmp_may_rst, CTLFLAG_RW, &icmp_may_rst, 0,
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213 "Certain ICMP unreachable messages may abort connections in SYN_SENT");
214
707ad4ed 215static int tcp_isn_reseed_interval = 0;
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216SYSCTL_INT(_net_inet_tcp, OID_AUTO, isn_reseed_interval, CTLFLAG_RW,
217 &tcp_isn_reseed_interval, 0, "Seconds between reseeding of ISN secret");
218
219/*
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220 * TCP bandwidth limiting sysctls. The inflight limiter is now turned on
221 * by default, but with generous values which should allow maximal
222 * bandwidth. In particular, the slop defaults to 50 (5 packets).
223 *
224 * The reason for doing this is that the limiter is the only mechanism we
225 * have which seems to do a really good job preventing receiver RX rings
226 * on network interfaces from getting blown out. Even though GigE/10GigE
227 * is supposed to flow control it looks like either it doesn't actually
228 * do it or Open Source drivers do not properly enable it.
229 *
230 * People using the limiter to reduce bottlenecks on slower WAN connections
231 * should set the slop to 20 (2 packets).
984263bc 232 */
d66b98eb 233static int tcp_inflight_enable = 1;
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234SYSCTL_INT(_net_inet_tcp, OID_AUTO, inflight_enable, CTLFLAG_RW,
235 &tcp_inflight_enable, 0, "Enable automatic TCP inflight data limiting");
236
707ad4ed 237static int tcp_inflight_debug = 0;
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238SYSCTL_INT(_net_inet_tcp, OID_AUTO, inflight_debug, CTLFLAG_RW,
239 &tcp_inflight_debug, 0, "Debug TCP inflight calculations");
240
707ad4ed 241static int tcp_inflight_min = 6144;
984263bc 242SYSCTL_INT(_net_inet_tcp, OID_AUTO, inflight_min, CTLFLAG_RW,
707ad4ed 243 &tcp_inflight_min, 0, "Lower bound for TCP inflight window");
984263bc 244
707ad4ed 245static int tcp_inflight_max = TCP_MAXWIN << TCP_MAX_WINSHIFT;
984263bc 246SYSCTL_INT(_net_inet_tcp, OID_AUTO, inflight_max, CTLFLAG_RW,
707ad4ed 247 &tcp_inflight_max, 0, "Upper bound for TCP inflight window");
984263bc 248
d66b98eb 249static int tcp_inflight_stab = 50;
984263bc 250SYSCTL_INT(_net_inet_tcp, OID_AUTO, inflight_stab, CTLFLAG_RW,
d66b98eb 251 &tcp_inflight_stab, 0, "Slop in maximal packets / 10 (20 = 3 packets)");
984263bc 252
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253static int tcp_do_rfc3390 = 1;
254SYSCTL_INT(_net_inet_tcp, OID_AUTO, rfc3390, CTLFLAG_RW,
255 &tcp_do_rfc3390, 0,
256 "Enable RFC 3390 (Increasing TCP's Initial Congestion Window)");
257
c01148a3 258static u_long tcp_iw_maxsegs = TCP_IW_MAXSEGS_DFLT;
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259SYSCTL_ULONG(_net_inet_tcp, OID_AUTO, iwmaxsegs, CTLFLAG_RW,
260 &tcp_iw_maxsegs, 0, "TCP IW segments max");
261
c01148a3 262static u_long tcp_iw_capsegs = TCP_IW_CAPSEGS_DFLT;
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263SYSCTL_ULONG(_net_inet_tcp, OID_AUTO, iwcapsegs, CTLFLAG_RW,
264 &tcp_iw_capsegs, 0, "TCP IW segments");
265
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266int tcp_low_rtobase = 1;
267SYSCTL_INT(_net_inet_tcp, OID_AUTO, low_rtobase, CTLFLAG_RW,
268 &tcp_low_rtobase, 0, "Lowering the Initial RTO (RFC 6298)");
269
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270static int tcp_do_ncr = 1;
271SYSCTL_INT(_net_inet_tcp, OID_AUTO, ncr, CTLFLAG_RW,
272 &tcp_do_ncr, 0, "Non-Congestion Robustness (RFC 4653)");
273
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274static MALLOC_DEFINE(M_TCPTEMP, "tcptemp", "TCP Templates for Keepalives");
275static struct malloc_pipe tcptemp_mpipe;
276
c3c96e44 277static void tcp_willblock(void);
707ad4ed 278static void tcp_notify (struct inpcb *, int);
984263bc 279
5f7ab76b 280struct tcp_stats tcpstats_percpu[MAXCPU];
1918fc5c 281
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282static int
283sysctl_tcpstats(SYSCTL_HANDLER_ARGS)
284{
707ad4ed 285 int cpu, error = 0;
2b57d013 286
707ad4ed 287 for (cpu = 0; cpu < ncpus; ++cpu) {
5f7ab76b 288 if ((error = SYSCTL_OUT(req, &tcpstats_percpu[cpu],
707ad4ed 289 sizeof(struct tcp_stats))))
2b57d013 290 break;
5f7ab76b 291 if ((error = SYSCTL_IN(req, &tcpstats_percpu[cpu],
707ad4ed 292 sizeof(struct tcp_stats))))
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MD
293 break;
294 }
295
296 return (error);
297}
707ad4ed
JH
298SYSCTL_PROC(_net_inet_tcp, TCPCTL_STATS, stats, (CTLTYPE_OPAQUE | CTLFLAG_RW),
299 0, 0, sysctl_tcpstats, "S,tcp_stats", "TCP statistics");
2b57d013 300
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301/*
302 * Target size of TCP PCB hash tables. Must be a power of two.
303 *
304 * Note that this can be overridden by the kernel environment
305 * variable net.inet.tcp.tcbhashsize
306 */
307#ifndef TCBHASHSIZE
707ad4ed 308#define TCBHASHSIZE 512
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309#endif
310
311/*
312 * This is the actual shape of what we allocate using the zone
313 * allocator. Doing it this way allows us to protect both structures
314 * using the same generation count, and also eliminates the overhead
315 * of allocating tcpcbs separately. By hiding the structure here,
316 * we avoid changing most of the rest of the code (although it needs
317 * to be changed, eventually, for greater efficiency).
318 */
319#define ALIGNMENT 32
320#define ALIGNM1 (ALIGNMENT - 1)
321struct inp_tp {
322 union {
323 struct inpcb inp;
324 char align[(sizeof(struct inpcb) + ALIGNM1) & ~ALIGNM1];
325 } inp_tp_u;
326 struct tcpcb tcb;
a48c5dd5
SZ
327 struct tcp_callout inp_tp_rexmt;
328 struct tcp_callout inp_tp_persist;
329 struct tcp_callout inp_tp_keep;
330 struct tcp_callout inp_tp_2msl;
331 struct tcp_callout inp_tp_delack;
0f758523 332 struct netmsg_tcp_timer inp_tp_timermsg;
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333};
334#undef ALIGNMENT
335#undef ALIGNM1
336
337/*
338 * Tcp initialization
339 */
340void
f3f70f0d 341tcp_init(void)
984263bc 342{
0ce0603e 343 struct inpcbporthead *porthashbase;
85095f20 344 struct inpcbinfo *ticb;
0ce0603e 345 u_long porthashmask;
984263bc 346 int hashsize = TCBHASHSIZE;
d371a63a 347 int cpu;
bf82f9b7 348
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349 /*
350 * note: tcptemp is used for keepalives, and it is ok for an
351 * allocation to fail so do not specify MPF_INT.
352 */
dd2b0fb4 353 mpipe_init(&tcptemp_mpipe, M_TCPTEMP, sizeof(struct tcptemp),
fdec03d6 354 25, -1, 0, NULL, NULL, NULL);
dd2b0fb4 355
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356 tcp_delacktime = TCPTV_DELACK;
357 tcp_keepinit = TCPTV_KEEP_INIT;
358 tcp_keepidle = TCPTV_KEEP_IDLE;
359 tcp_keepintvl = TCPTV_KEEPINTVL;
360 tcp_maxpersistidle = TCPTV_KEEP_IDLE;
361 tcp_msl = TCPTV_MSL;
362 tcp_rexmit_min = TCPTV_MIN;
363 tcp_rexmit_slop = TCPTV_CPU_VAR;
364
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365 TUNABLE_INT_FETCH("net.inet.tcp.tcbhashsize", &hashsize);
366 if (!powerof2(hashsize)) {
a6ec04bc 367 kprintf("WARNING: TCB hash size not a power of 2\n");
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368 hashsize = 512; /* safe default */
369 }
370 tcp_tcbhashsize = hashsize;
0ce0603e 371 porthashbase = hashinit(hashsize, M_PCB, &porthashmask);
d371a63a
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372
373 for (cpu = 0; cpu < ncpus2; cpu++) {
85095f20
MD
374 ticb = &tcbinfo[cpu];
375 in_pcbinfo_init(ticb);
376 ticb->cpu = cpu;
377 ticb->hashbase = hashinit(hashsize, M_PCB,
378 &ticb->hashmask);
0ce0603e
MD
379 ticb->porthashbase = porthashbase;
380 ticb->porthashmask = porthashmask;
381 ticb->porttoken = &tcp_port_token;
382#if 0
85095f20
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383 ticb->porthashbase = hashinit(hashsize, M_PCB,
384 &ticb->porthashmask);
0ce0603e 385#endif
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386 ticb->wildcardhashbase = hashinit(hashsize, M_PCB,
387 &ticb->wildcardhashmask);
388 ticb->ipi_size = sizeof(struct inp_tp);
2b1ce38a 389 TAILQ_INIT(&tcpcbackq[cpu]);
d371a63a 390 }
3edf7c37
RG
391
392 tcp_reass_maxseg = nmbclusters / 16;
707ad4ed 393 TUNABLE_INT_FETCH("net.inet.tcp.reass.maxsegments", &tcp_reass_maxseg);
3edf7c37 394
984263bc 395#ifdef INET6
707ad4ed
JH
396#define TCP_MINPROTOHDR (sizeof(struct ip6_hdr) + sizeof(struct tcphdr))
397#else
398#define TCP_MINPROTOHDR (sizeof(struct tcpiphdr))
399#endif
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MD
400 if (max_protohdr < TCP_MINPROTOHDR)
401 max_protohdr = TCP_MINPROTOHDR;
402 if (max_linkhdr + TCP_MINPROTOHDR > MHLEN)
403 panic("tcp_init");
404#undef TCP_MINPROTOHDR
405
2b57d013 406 /*
5f7ab76b 407 * Initialize TCP statistics counters for each CPU.
2b57d013 408 */
2b57d013 409 for (cpu = 0; cpu < ncpus; ++cpu) {
5f7ab76b 410 bzero(&tcpstats_percpu[cpu], sizeof(struct tcp_stats));
2b57d013 411 }
2b57d013 412
984263bc 413 syncache_init();
c3c96e44 414 netisr_register_rollup(tcp_willblock);
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MD
415}
416
417static void
c3c96e44 418tcp_willblock(void)
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MD
419{
420 struct tcpcb *tp;
421 int cpu = mycpu->gd_cpuid;
422
423 while ((tp = TAILQ_FIRST(&tcpcbackq[cpu])) != NULL) {
424 KKASSERT(tp->t_flags & TF_ONOUTPUTQ);
425 tp->t_flags &= ~TF_ONOUTPUTQ;
426 TAILQ_REMOVE(&tcpcbackq[cpu], tp, t_outputq);
427 tcp_output(tp);
428 }
429}
430
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431/*
432 * Fill in the IP and TCP headers for an outgoing packet, given the tcpcb.
433 * tcp_template used to store this data in mbufs, but we now recopy it out
434 * of the tcpcb each time to conserve mbufs.
435 */
436void
5f60906c 437tcp_fillheaders(struct tcpcb *tp, void *ip_ptr, void *tcp_ptr, boolean_t tso)
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438{
439 struct inpcb *inp = tp->t_inpcb;
440 struct tcphdr *tcp_hdr = (struct tcphdr *)tcp_ptr;
441
442#ifdef INET6
707ad4ed 443 if (inp->inp_vflag & INP_IPV6) {
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444 struct ip6_hdr *ip6;
445
446 ip6 = (struct ip6_hdr *)ip_ptr;
447 ip6->ip6_flow = (ip6->ip6_flow & ~IPV6_FLOWINFO_MASK) |
448 (inp->in6p_flowinfo & IPV6_FLOWINFO_MASK);
449 ip6->ip6_vfc = (ip6->ip6_vfc & ~IPV6_VERSION_MASK) |
450 (IPV6_VERSION & IPV6_VERSION_MASK);
451 ip6->ip6_nxt = IPPROTO_TCP;
452 ip6->ip6_plen = sizeof(struct tcphdr);
453 ip6->ip6_src = inp->in6p_laddr;
454 ip6->ip6_dst = inp->in6p_faddr;
455 tcp_hdr->th_sum = 0;
456 } else
457#endif
458 {
707ad4ed 459 struct ip *ip = (struct ip *) ip_ptr;
5f60906c 460 u_int plen;
707ad4ed
JH
461
462 ip->ip_vhl = IP_VHL_BORING;
463 ip->ip_tos = 0;
464 ip->ip_len = 0;
465 ip->ip_id = 0;
466 ip->ip_off = 0;
467 ip->ip_ttl = 0;
468 ip->ip_sum = 0;
469 ip->ip_p = IPPROTO_TCP;
470 ip->ip_src = inp->inp_laddr;
471 ip->ip_dst = inp->inp_faddr;
5f60906c
SZ
472
473 if (tso)
474 plen = htons(IPPROTO_TCP);
475 else
476 plen = htons(sizeof(struct tcphdr) + IPPROTO_TCP);
707ad4ed 477 tcp_hdr->th_sum = in_pseudo(ip->ip_src.s_addr,
5f60906c 478 ip->ip_dst.s_addr, plen);
984263bc
MD
479 }
480
481 tcp_hdr->th_sport = inp->inp_lport;
482 tcp_hdr->th_dport = inp->inp_fport;
483 tcp_hdr->th_seq = 0;
484 tcp_hdr->th_ack = 0;
485 tcp_hdr->th_x2 = 0;
486 tcp_hdr->th_off = 5;
487 tcp_hdr->th_flags = 0;
488 tcp_hdr->th_win = 0;
489 tcp_hdr->th_urp = 0;
490}
491
492/*
493 * Create template to be used to send tcp packets on a connection.
494 * Allocates an mbuf and fills in a skeletal tcp/ip header. The only
495 * use for this function is in keepalives, which use tcp_respond.
496 */
497struct tcptemp *
707ad4ed 498tcp_maketemplate(struct tcpcb *tp)
984263bc 499{
dd2b0fb4 500 struct tcptemp *tmp;
984263bc 501
dd2b0fb4 502 if ((tmp = mpipe_alloc_nowait(&tcptemp_mpipe)) == NULL)
707ad4ed 503 return (NULL);
5f60906c 504 tcp_fillheaders(tp, &tmp->tt_ipgen, &tmp->tt_t, FALSE);
dd2b0fb4
MD
505 return (tmp);
506}
984263bc 507
dd2b0fb4
MD
508void
509tcp_freetemplate(struct tcptemp *tmp)
510{
511 mpipe_free(&tcptemp_mpipe, tmp);
984263bc
MD
512}
513
514/*
515 * Send a single message to the TCP at address specified by
707ad4ed 516 * the given TCP/IP header. If m == NULL, then we make a copy
984263bc
MD
517 * of the tcpiphdr at ti and send directly to the addressed host.
518 * This is used to force keep alive messages out using the TCP
519 * template for a connection. If flags are given then we send
520 * a message back to the TCP which originated the * segment ti,
521 * and discard the mbuf containing it and any other attached mbufs.
522 *
523 * In any case the ack and sequence number of the transmitted
524 * segment are as specified by the parameters.
525 *
526 * NOTE: If m != NULL, then ti must point to *inside* the mbuf.
527 */
528void
707ad4ed
JH
529tcp_respond(struct tcpcb *tp, void *ipgen, struct tcphdr *th, struct mbuf *m,
530 tcp_seq ack, tcp_seq seq, int flags)
984263bc 531{
2256ba69 532 int tlen;
984263bc 533 int win = 0;
707ad4ed 534 struct route *ro = NULL;
984263bc 535 struct route sro;
707ad4ed 536 struct ip *ip = ipgen;
984263bc 537 struct tcphdr *nth;
984263bc 538 int ipflags = 0;
707ad4ed
JH
539 struct route_in6 *ro6 = NULL;
540 struct route_in6 sro6;
541 struct ip6_hdr *ip6 = ipgen;
5a0e5b43 542 boolean_t use_tmpro = TRUE;
984263bc 543#ifdef INET6
707ad4ed
JH
544 boolean_t isipv6 = (IP_VHL_V(ip->ip_vhl) == 6);
545#else
546 const boolean_t isipv6 = FALSE;
547#endif
984263bc 548
707ad4ed 549 if (tp != NULL) {
984263bc 550 if (!(flags & TH_RST)) {
6d49aa6f 551 win = ssb_space(&tp->t_inpcb->inp_socket->so_rcv);
46e92930
MD
552 if (win < 0)
553 win = 0;
984263bc
MD
554 if (win > (long)TCP_MAXWIN << tp->rcv_scale)
555 win = (long)TCP_MAXWIN << tp->rcv_scale;
556 }
5a0e5b43
SZ
557 /*
558 * Don't use the route cache of a listen socket,
559 * it is not MPSAFE; use temporary route cache.
560 */
561 if (tp->t_state != TCPS_LISTEN) {
562 if (isipv6)
563 ro6 = &tp->t_inpcb->in6p_route;
564 else
565 ro = &tp->t_inpcb->inp_route;
566 use_tmpro = FALSE;
567 }
568 }
569 if (use_tmpro) {
984263bc
MD
570 if (isipv6) {
571 ro6 = &sro6;
572 bzero(ro6, sizeof *ro6);
707ad4ed
JH
573 } else {
574 ro = &sro;
575 bzero(ro, sizeof *ro);
576 }
984263bc 577 }
707ad4ed 578 if (m == NULL) {
74f1caca 579 m = m_gethdr(MB_DONTWAIT, MT_HEADER);
984263bc
MD
580 if (m == NULL)
581 return;
582 tlen = 0;
583 m->m_data += max_linkhdr;
984263bc 584 if (isipv6) {
707ad4ed 585 bcopy(ip6, mtod(m, caddr_t), sizeof(struct ip6_hdr));
984263bc
MD
586 ip6 = mtod(m, struct ip6_hdr *);
587 nth = (struct tcphdr *)(ip6 + 1);
707ad4ed
JH
588 } else {
589 bcopy(ip, mtod(m, caddr_t), sizeof(struct ip));
590 ip = mtod(m, struct ip *);
591 nth = (struct tcphdr *)(ip + 1);
592 }
593 bcopy(th, nth, sizeof(struct tcphdr));
984263bc
MD
594 flags = TH_ACK;
595 } else {
596 m_freem(m->m_next);
707ad4ed 597 m->m_next = NULL;
984263bc
MD
598 m->m_data = (caddr_t)ipgen;
599 /* m_len is set later */
600 tlen = 0;
707ad4ed 601#define xchg(a, b, type) { type t; t = a; a = b; b = t; }
984263bc
MD
602 if (isipv6) {
603 xchg(ip6->ip6_dst, ip6->ip6_src, struct in6_addr);
604 nth = (struct tcphdr *)(ip6 + 1);
707ad4ed
JH
605 } else {
606 xchg(ip->ip_dst.s_addr, ip->ip_src.s_addr, n_long);
607 nth = (struct tcphdr *)(ip + 1);
608 }
984263bc
MD
609 if (th != nth) {
610 /*
611 * this is usually a case when an extension header
612 * exists between the IPv6 header and the
613 * TCP header.
614 */
615 nth->th_sport = th->th_sport;
616 nth->th_dport = th->th_dport;
617 }
618 xchg(nth->th_dport, nth->th_sport, n_short);
619#undef xchg
620 }
984263bc
MD
621 if (isipv6) {
622 ip6->ip6_flow = 0;
623 ip6->ip6_vfc = IPV6_VERSION;
624 ip6->ip6_nxt = IPPROTO_TCP;
707ad4ed
JH
625 ip6->ip6_plen = htons((u_short)(sizeof(struct tcphdr) + tlen));
626 tlen += sizeof(struct ip6_hdr) + sizeof(struct tcphdr);
627 } else {
628 tlen += sizeof(struct tcpiphdr);
629 ip->ip_len = tlen;
630 ip->ip_ttl = ip_defttl;
631 }
984263bc
MD
632 m->m_len = tlen;
633 m->m_pkthdr.len = tlen;
2038fb68 634 m->m_pkthdr.rcvif = NULL;
984263bc
MD
635 nth->th_seq = htonl(seq);
636 nth->th_ack = htonl(ack);
637 nth->th_x2 = 0;
707ad4ed 638 nth->th_off = sizeof(struct tcphdr) >> 2;
984263bc 639 nth->th_flags = flags;
707ad4ed 640 if (tp != NULL)
984263bc
MD
641 nth->th_win = htons((u_short) (win >> tp->rcv_scale));
642 else
643 nth->th_win = htons((u_short)win);
644 nth->th_urp = 0;
984263bc
MD
645 if (isipv6) {
646 nth->th_sum = 0;
647 nth->th_sum = in6_cksum(m, IPPROTO_TCP,
648 sizeof(struct ip6_hdr),
649 tlen - sizeof(struct ip6_hdr));
650 ip6->ip6_hlim = in6_selecthlim(tp ? tp->t_inpcb : NULL,
707ad4ed 651 (ro6 && ro6->ro_rt) ?
f23061d4 652 ro6->ro_rt->rt_ifp : NULL);
707ad4ed
JH
653 } else {
654 nth->th_sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr,
655 htons((u_short)(tlen - sizeof(struct ip) + ip->ip_p)));
656 m->m_pkthdr.csum_flags = CSUM_TCP;
657 m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum);
7df36335 658 m->m_pkthdr.csum_thlen = sizeof(struct tcphdr);
707ad4ed 659 }
984263bc
MD
660#ifdef TCPDEBUG
661 if (tp == NULL || (tp->t_inpcb->inp_socket->so_options & SO_DEBUG))
662 tcp_trace(TA_OUTPUT, 0, tp, mtod(m, void *), th, 0);
663#endif
984263bc 664 if (isipv6) {
f23061d4
JH
665 ip6_output(m, NULL, ro6, ipflags, NULL, NULL,
666 tp ? tp->t_inpcb : NULL);
707ad4ed 667 if ((ro6 == &sro6) && (ro6->ro_rt != NULL)) {
984263bc
MD
668 RTFREE(ro6->ro_rt);
669 ro6->ro_rt = NULL;
670 }
707ad4ed 671 } else {
1dbb3516 672 ipflags |= IP_DEBUGROUTE;
f23061d4 673 ip_output(m, NULL, ro, ipflags, NULL, tp ? tp->t_inpcb : NULL);
707ad4ed
JH
674 if ((ro == &sro) && (ro->ro_rt != NULL)) {
675 RTFREE(ro->ro_rt);
676 ro->ro_rt = NULL;
677 }
984263bc 678 }
984263bc
MD
679}
680
681/*
682 * Create a new TCP control block, making an
683 * empty reassembly queue and hooking it to the argument
684 * protocol control block. The `inp' parameter must have
685 * come from the zone allocator set up in tcp_init().
686 */
687struct tcpcb *
707ad4ed 688tcp_newtcpcb(struct inpcb *inp)
984263bc
MD
689{
690 struct inp_tp *it;
2256ba69 691 struct tcpcb *tp;
984263bc 692#ifdef INET6
707ad4ed
JH
693 boolean_t isipv6 = ((inp->inp_vflag & INP_IPV6) != 0);
694#else
695 const boolean_t isipv6 = FALSE;
696#endif
984263bc
MD
697
698 it = (struct inp_tp *)inp;
699 tp = &it->tcb;
707ad4ed 700 bzero(tp, sizeof(struct tcpcb));
0f9e45de 701 TAILQ_INIT(&tp->t_segq);
707ad4ed 702 tp->t_maxseg = tp->t_maxopd = isipv6 ? tcp_v6mssdflt : tcp_mssdflt;
7e4852bb 703 tp->t_rxtthresh = tcprexmtthresh;
984263bc
MD
704
705 /* Set up our timeouts. */
a48c5dd5
SZ
706 tp->tt_rexmt = &it->inp_tp_rexmt;
707 tp->tt_persist = &it->inp_tp_persist;
708 tp->tt_keep = &it->inp_tp_keep;
709 tp->tt_2msl = &it->inp_tp_2msl;
710 tp->tt_delack = &it->inp_tp_delack;
711 tcp_inittimers(tp);
984263bc 712
3db1c8a3
SZ
713 /*
714 * Zero out timer message. We don't create it here,
715 * since the current CPU may not be the owner of this
716 * inpcb.
717 */
0f758523 718 tp->tt_msg = &it->inp_tp_timermsg;
3db1c8a3 719 bzero(tp->tt_msg, sizeof(*tp->tt_msg));
0f758523 720
2ce132be 721 tp->t_keepinit = tcp_keepinit;
7ea3a353 722 tp->t_keepidle = tcp_keepidle;
5d61ded3
SZ
723 tp->t_keepintvl = tcp_keepintvl;
724 tp->t_keepcnt = tcp_keepcnt;
725 tp->t_maxidle = tp->t_keepintvl * tp->t_keepcnt;
2ce132be 726
e2289e66
SZ
727 if (tcp_do_ncr)
728 tp->t_flags |= TF_NCR;
984263bc 729 if (tcp_do_rfc1323)
e2289e66
SZ
730 tp->t_flags |= (TF_REQ_SCALE | TF_REQ_TSTMP);
731
984263bc 732 tp->t_inpcb = inp; /* XXX */
eb594563 733 tp->t_state = TCPS_CLOSED;
984263bc
MD
734 /*
735 * Init srtt to TCPTV_SRTTBASE (0), so we can tell that we have no
736 * rtt estimate. Set rttvar so that srtt + 4 * rttvar gives
737 * reasonable initial retransmit time.
738 */
739 tp->t_srtt = TCPTV_SRTTBASE;
707ad4ed
JH
740 tp->t_rttvar =
741 ((TCPTV_RTOBASE - TCPTV_SRTTBASE) << TCP_RTTVAR_SHIFT) / 4;
984263bc
MD
742 tp->t_rttmin = tcp_rexmit_min;
743 tp->t_rxtcur = TCPTV_RTOBASE;
744 tp->snd_cwnd = TCP_MAXWIN << TCP_MAX_WINSHIFT;
745 tp->snd_bwnd = TCP_MAXWIN << TCP_MAX_WINSHIFT;
746 tp->snd_ssthresh = TCP_MAXWIN << TCP_MAX_WINSHIFT;
3d127502 747 tp->snd_last = ticks;
984263bc 748 tp->t_rcvtime = ticks;
707ad4ed 749 /*
984263bc
MD
750 * IPv4 TTL initialization is necessary for an IPv6 socket as well,
751 * because the socket may be bound to an IPv6 wildcard address,
752 * which may match an IPv4-mapped IPv6 address.
753 */
754 inp->inp_ip_ttl = ip_defttl;
f23061d4 755 inp->inp_ppcb = tp;
91489f6b 756 tcp_sack_tcpcb_init(tp);
984263bc
MD
757 return (tp); /* XXX */
758}
759
760/*
707ad4ed
JH
761 * Drop a TCP connection, reporting the specified error.
762 * If connection is synchronized, then send a RST to peer.
984263bc
MD
763 */
764struct tcpcb *
71f385dc 765tcp_drop(struct tcpcb *tp, int error)
984263bc
MD
766{
767 struct socket *so = tp->t_inpcb->inp_socket;
768
769 if (TCPS_HAVERCVDSYN(tp->t_state)) {
770 tp->t_state = TCPS_CLOSED;
f23061d4 771 tcp_output(tp);
984263bc
MD
772 tcpstat.tcps_drops++;
773 } else
774 tcpstat.tcps_conndrops++;
71f385dc
MD
775 if (error == ETIMEDOUT && tp->t_softerror)
776 error = tp->t_softerror;
777 so->so_error = error;
984263bc
MD
778 return (tcp_close(tp));
779}
780
ce6f0462 781struct netmsg_listen_detach {
002c1265 782 struct netmsg_base base;
ce6f0462 783 struct tcpcb *nm_tp;
8affadf8
JH
784};
785
4599cf19 786static void
ce6f0462 787tcp_listen_detach_handler(netmsg_t msg)
8affadf8 788{
ce6f0462
SZ
789 struct netmsg_listen_detach *nmsg = (struct netmsg_listen_detach *)msg;
790 struct tcpcb *tp = nmsg->nm_tp;
791 int cpu = mycpuid, nextcpu;
8affadf8 792
f7b29de5 793 if (tp->t_flags & TF_LISTEN)
ce6f0462 794 syncache_destroy(tp);
eb594563 795
ce6f0462
SZ
796 in_pcbremwildcardhash_oncpu(tp->t_inpcb, &tcbinfo[cpu]);
797
798 nextcpu = cpu + 1;
799 if (nextcpu < ncpus2)
3abced87 800 lwkt_forwardmsg(netisr_portfn(nextcpu), &nmsg->base.lmsg);
ce6f0462 801 else
002c1265 802 lwkt_replymsg(&nmsg->base.lmsg, 0);
8affadf8 803}
eb594563 804
984263bc
MD
805/*
806 * Close a TCP control block:
807 * discard all space held by the tcp
808 * discard internet protocol block
809 * wake up any sleepers
810 */
811struct tcpcb *
707ad4ed 812tcp_close(struct tcpcb *tp)
984263bc 813{
2256ba69 814 struct tseg_qent *q;
984263bc
MD
815 struct inpcb *inp = tp->t_inpcb;
816 struct socket *so = inp->inp_socket;
2256ba69 817 struct rtentry *rt;
707ad4ed
JH
818 boolean_t dosavessthresh;
819#ifdef INET6
820 boolean_t isipv6 = ((inp->inp_vflag & INP_IPV6) != 0);
eb594563 821 boolean_t isafinet6 = (INP_CHECK_SOCKAF(so, AF_INET6) != 0);
707ad4ed
JH
822#else
823 const boolean_t isipv6 = FALSE;
824#endif
984263bc 825
eb594563 826 /*
ce6f0462
SZ
827 * INP_WILDCARD_MP indicates that listen(2) has been called on
828 * this socket. This implies:
829 * - A wildcard inp's hash is replicated for each protocol thread.
830 * - Syncache for this inp grows independently in each protocol
831 * thread.
985b2cb0 832 * - There is more than one cpu
eb594563 833 *
ce6f0462
SZ
834 * We have to chain a message to the rest of the protocol threads
835 * to cleanup the wildcard hash and the syncache. The cleanup
836 * in the current protocol thread is defered till the end of this
837 * function.
838 *
839 * NOTE:
840 * After cleanup the inp's hash and syncache entries, this inp will
841 * no longer be available to the rest of the protocol threads, so we
842 * are safe to whack the inp in the following code.
eb594563 843 */
ce6f0462
SZ
844 if (inp->inp_flags & INP_WILDCARD_MP) {
845 struct netmsg_listen_detach nmsg;
846
3abced87
NA
847 KKASSERT(so->so_port == netisr_portfn(0));
848 KKASSERT(&curthread->td_msgport == netisr_portfn(0));
ce6f0462
SZ
849 KKASSERT(inp->inp_pcbinfo == &tcbinfo[0]);
850
851 netmsg_init(&nmsg.base, NULL, &curthread->td_msgport,
852 MSGF_PRIORITY, tcp_listen_detach_handler);
853 nmsg.nm_tp = tp;
3abced87 854 lwkt_domsg(netisr_portfn(1), &nmsg.base.lmsg, 0);
ce6f0462
SZ
855
856 inp->inp_flags &= ~INP_WILDCARD_MP;
857 }
ce6f0462 858
eb594563
MD
859 KKASSERT(tp->t_state != TCPS_TERMINATING);
860 tp->t_state = TCPS_TERMINATING;
861
984263bc
MD
862 /*
863 * Make sure that all of our timers are stopped before we
2d42d2b0 864 * delete the PCB. For listen TCP socket (tp->tt_msg == NULL),
697aadcd
SZ
865 * timers are never used. If timer message is never created
866 * (tp->tt_msg->tt_tcb == NULL), timers are never used too.
984263bc 867 */
697aadcd 868 if (tp->tt_msg != NULL && tp->tt_msg->tt_tcb != NULL) {
2d42d2b0
SZ
869 tcp_callout_stop(tp, tp->tt_rexmt);
870 tcp_callout_stop(tp, tp->tt_persist);
871 tcp_callout_stop(tp, tp->tt_keep);
872 tcp_callout_stop(tp, tp->tt_2msl);
873 tcp_callout_stop(tp, tp->tt_delack);
874 }
984263bc 875
2b1ce38a
MD
876 if (tp->t_flags & TF_ONOUTPUTQ) {
877 KKASSERT(tp->tt_cpu == mycpu->gd_cpuid);
878 TAILQ_REMOVE(&tcpcbackq[tp->tt_cpu], tp, t_outputq);
879 tp->t_flags &= ~TF_ONOUTPUTQ;
880 }
881
984263bc
MD
882 /*
883 * If we got enough samples through the srtt filter,
884 * save the rtt and rttvar in the routing entry.
885 * 'Enough' is arbitrarily defined as the 16 samples.
886 * 16 samples is enough for the srtt filter to converge
887 * to within 5% of the correct value; fewer samples and
888 * we could save a very bogus rtt.
889 *
890 * Don't update the default route's characteristics and don't
891 * update anything that the user "locked".
892 */
893 if (tp->t_rttupdated >= 16) {
2256ba69 894 u_long i = 0;
707ad4ed 895
984263bc
MD
896 if (isipv6) {
897 struct sockaddr_in6 *sin6;
898
899 if ((rt = inp->in6p_route.ro_rt) == NULL)
900 goto no_valid_rt;
901 sin6 = (struct sockaddr_in6 *)rt_key(rt);
902 if (IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr))
903 goto no_valid_rt;
707ad4ed
JH
904 } else
905 if ((rt = inp->inp_route.ro_rt) == NULL ||
906 ((struct sockaddr_in *)rt_key(rt))->
907 sin_addr.s_addr == INADDR_ANY)
908 goto no_valid_rt;
909
910 if (!(rt->rt_rmx.rmx_locks & RTV_RTT)) {
911 i = tp->t_srtt * (RTM_RTTUNIT / (hz * TCP_RTT_SCALE));
984263bc
MD
912 if (rt->rt_rmx.rmx_rtt && i)
913 /*
914 * filter this update to half the old & half
915 * the new values, converting scale.
916 * See route.h and tcp_var.h for a
917 * description of the scaling constants.
918 */
919 rt->rt_rmx.rmx_rtt =
920 (rt->rt_rmx.rmx_rtt + i) / 2;
921 else
922 rt->rt_rmx.rmx_rtt = i;
923 tcpstat.tcps_cachedrtt++;
924 }
707ad4ed 925 if (!(rt->rt_rmx.rmx_locks & RTV_RTTVAR)) {
984263bc
MD
926 i = tp->t_rttvar *
927 (RTM_RTTUNIT / (hz * TCP_RTTVAR_SCALE));
928 if (rt->rt_rmx.rmx_rttvar && i)
929 rt->rt_rmx.rmx_rttvar =
930 (rt->rt_rmx.rmx_rttvar + i) / 2;
931 else
932 rt->rt_rmx.rmx_rttvar = i;
933 tcpstat.tcps_cachedrttvar++;
934 }
935 /*
936 * The old comment here said:
937 * update the pipelimit (ssthresh) if it has been updated
938 * already or if a pipesize was specified & the threshhold
939 * got below half the pipesize. I.e., wait for bad news
940 * before we start updating, then update on both good
941 * and bad news.
942 *
943 * But we want to save the ssthresh even if no pipesize is
944 * specified explicitly in the route, because such
945 * connections still have an implicit pipesize specified
946 * by the global tcp_sendspace. In the absence of a reliable
947 * way to calculate the pipesize, it will have to do.
948 */
949 i = tp->snd_ssthresh;
950 if (rt->rt_rmx.rmx_sendpipe != 0)
707ad4ed 951 dosavessthresh = (i < rt->rt_rmx.rmx_sendpipe/2);
984263bc 952 else
6d49aa6f 953 dosavessthresh = (i < so->so_snd.ssb_hiwat/2);
707ad4ed
JH
954 if (dosavessthresh ||
955 (!(rt->rt_rmx.rmx_locks & RTV_SSTHRESH) && (i != 0) &&
956 (rt->rt_rmx.rmx_ssthresh != 0))) {
984263bc
MD
957 /*
958 * convert the limit from user data bytes to
959 * packets then to packet data bytes.
960 */
961 i = (i + tp->t_maxseg / 2) / tp->t_maxseg;
962 if (i < 2)
963 i = 2;
707ad4ed
JH
964 i *= tp->t_maxseg +
965 (isipv6 ?
966 sizeof(struct ip6_hdr) + sizeof(struct tcphdr) :
967 sizeof(struct tcpiphdr));
984263bc
MD
968 if (rt->rt_rmx.rmx_ssthresh)
969 rt->rt_rmx.rmx_ssthresh =
970 (rt->rt_rmx.rmx_ssthresh + i) / 2;
971 else
972 rt->rt_rmx.rmx_ssthresh = i;
973 tcpstat.tcps_cachedssthresh++;
974 }
975 }
707ad4ed
JH
976
977no_valid_rt:
984263bc 978 /* free the reassembly queue, if any */
0f9e45de
SZ
979 while((q = TAILQ_FIRST(&tp->t_segq)) != NULL) {
980 TAILQ_REMOVE(&tp->t_segq, q, tqe_q);
984263bc 981 m_freem(q->tqe_m);
884717e1 982 kfree(q, M_TSEGQ);
2d23a8be 983 atomic_add_int(&tcp_reass_qsize, -1);
984263bc 984 }
4617a559 985 /* throw away SACK blocks in scoreboard*/
91489f6b 986 if (TCP_DO_SACK(tp))
006af0db 987 tcp_sack_destroy(&tp->scb);
eb594563 988
4617a559 989 inp->inp_ppcb = NULL;
984263bc 990 soisdisconnected(so);
4617a559
MD
991 /* note: pcb detached later on */
992
0f758523 993 tcp_destroy_timermsg(tp);
ce6f0462 994
f7b29de5 995 if (tp->t_flags & TF_LISTEN)
e5fe3477 996 syncache_destroy(tp);
0f758523 997
96c6eb29
SZ
998 so_async_rcvd_drop(so);
999
eb594563 1000 /*
ce6f0462
SZ
1001 * NOTE:
1002 * pcbdetach removes any wildcard hash entry on the current CPU.
eb594563 1003 */
984263bc 1004#ifdef INET6
ce6f0462
SZ
1005 if (isafinet6)
1006 in6_pcbdetach(inp);
1007 else
707ad4ed 1008#endif
ce6f0462
SZ
1009 in_pcbdetach(inp);
1010
984263bc 1011 tcpstat.tcps_closed++;
707ad4ed 1012 return (NULL);
984263bc
MD
1013}
1014
3f48f9c5
JH
1015static __inline void
1016tcp_drain_oncpu(struct inpcbhead *head)
984263bc 1017{
2d23a8be 1018 struct inpcb *marker;
d371a63a
JH
1019 struct inpcb *inpb;
1020 struct tcpcb *tcpb;
1021 struct tseg_qent *te;
3f48f9c5 1022
2d23a8be
MD
1023 /*
1024 * Allows us to block while running the list
1025 */
1026 marker = kmalloc(sizeof(struct inpcb), M_TEMP, M_WAITOK|M_ZERO);
1027 marker->inp_flags |= INP_PLACEMARKER;
1028 LIST_INSERT_HEAD(head, marker, inp_list);
1029
1030 while ((inpb = LIST_NEXT(marker, inp_list)) != NULL) {
1031 if ((inpb->inp_flags & INP_PLACEMARKER) == 0 &&
1032 (tcpb = intotcpcb(inpb)) != NULL &&
0f9e45de
SZ
1033 (te = TAILQ_FIRST(&tcpb->t_segq)) != NULL) {
1034 TAILQ_REMOVE(&tcpb->t_segq, te, tqe_q);
942d88ef
SZ
1035 if (te->tqe_th->th_flags & TH_FIN)
1036 tcpb->t_flags &= ~TF_QUEDFIN;
2d23a8be 1037 m_freem(te->tqe_m);
884717e1 1038 kfree(te, M_TSEGQ);
2d23a8be
MD
1039 atomic_add_int(&tcp_reass_qsize, -1);
1040 /* retry */
1041 } else {
1042 LIST_REMOVE(marker, inp_list);
1043 LIST_INSERT_AFTER(inpb, marker, inp_list);
3f48f9c5
JH
1044 }
1045 }
2d23a8be
MD
1046 LIST_REMOVE(marker, inp_list);
1047 kfree(marker, M_TEMP);
3f48f9c5
JH
1048}
1049
0ddb6032 1050struct netmsg_tcp_drain {
002c1265 1051 struct netmsg_base base;
0ddb6032
JH
1052 struct inpcbhead *nm_head;
1053};
1054
4599cf19 1055static void
002c1265 1056tcp_drain_handler(netmsg_t msg)
0ddb6032 1057{
002c1265 1058 struct netmsg_tcp_drain *nm = (void *)msg;
0ddb6032
JH
1059
1060 tcp_drain_oncpu(nm->nm_head);
002c1265 1061 lwkt_replymsg(&nm->base.lmsg, 0);
0ddb6032 1062}
0ddb6032 1063
3f48f9c5 1064void
f3f70f0d 1065tcp_drain(void)
3f48f9c5 1066{
d371a63a
JH
1067 int cpu;
1068
1069 if (!do_tcpdrain)
1070 return;
984263bc
MD
1071
1072 /*
1073 * Walk the tcpbs, if existing, and flush the reassembly queue,
1074 * if there is one...
1075 * XXX: The "Net/3" implementation doesn't imply that the TCP
707ad4ed
JH
1076 * reassembly queue should be flushed, but in a situation
1077 * where we're really low on mbufs, this is potentially
1078 * useful.
984263bc 1079 */
d371a63a 1080 for (cpu = 0; cpu < ncpus2; cpu++) {
002c1265 1081 struct netmsg_tcp_drain *nm;
3f48f9c5 1082
0ddb6032 1083 if (cpu == mycpu->gd_cpuid) {
d2e9e54c 1084 tcp_drain_oncpu(&tcbinfo[cpu].pcblisthead);
3f48f9c5 1085 } else {
002c1265
MD
1086 nm = kmalloc(sizeof(struct netmsg_tcp_drain),
1087 M_LWKTMSG, M_NOWAIT);
1088 if (nm == NULL)
3f48f9c5 1089 continue;
002c1265 1090 netmsg_init(&nm->base, NULL, &netisr_afree_rport,
48e7b118 1091 0, tcp_drain_handler);
002c1265 1092 nm->nm_head = &tcbinfo[cpu].pcblisthead;
3abced87 1093 lwkt_sendmsg(netisr_portfn(cpu), &nm->base.lmsg);
984263bc 1094 }
984263bc
MD
1095 }
1096}
1097
1098/*
1099 * Notify a tcp user of an asynchronous error;
1100 * store error as soft error, but wake up user
1101 * (for now, won't do anything until can select for soft error).
1102 *
1103 * Do not wake up user since there currently is no mechanism for
1104 * reporting soft errors (yet - a kqueue filter may be added).
1105 */
1106static void
707ad4ed 1107tcp_notify(struct inpcb *inp, int error)
984263bc 1108{
707ad4ed 1109 struct tcpcb *tp = intotcpcb(inp);
984263bc
MD
1110
1111 /*
1112 * Ignore some errors if we are hooked up.
1113 * If connection hasn't completed, has retransmitted several times,
1114 * and receives a second error, give up now. This is better
1115 * than waiting a long time to establish a connection that
1116 * can never complete.
1117 */
1118 if (tp->t_state == TCPS_ESTABLISHED &&
1119 (error == EHOSTUNREACH || error == ENETUNREACH ||
1120 error == EHOSTDOWN)) {
1121 return;
1122 } else if (tp->t_state < TCPS_ESTABLISHED && tp->t_rxtshift > 3 &&
1123 tp->t_softerror)
1124 tcp_drop(tp, error);
1125 else
1126 tp->t_softerror = error;
1127#if 0
f23061d4 1128 wakeup(&so->so_timeo);
984263bc
MD
1129 sorwakeup(so);
1130 sowwakeup(so);
1131#endif
1132}
1133
1134static int
1135tcp_pcblist(SYSCTL_HANDLER_ARGS)
1136{
d2e9e54c
MD
1137 int error, i, n;
1138 struct inpcb *marker;
1139 struct inpcb *inp;
d2e9e54c
MD
1140 globaldata_t gd;
1141 int origcpu, ccpu;
1142
1143 error = 0;
1144 n = 0;
984263bc
MD
1145
1146 /*
1147 * The process of preparing the TCB list is too time-consuming and
1148 * resource-intensive to repeat twice on every request.
1149 */
707ad4ed 1150 if (req->oldptr == NULL) {
d2e9e54c
MD
1151 for (ccpu = 0; ccpu < ncpus; ++ccpu) {
1152 gd = globaldata_find(ccpu);
1153 n += tcbinfo[gd->gd_cpuid].ipi_count;
1154 }
8d7c364e 1155 req->oldidx = (n + n/8 + 10) * sizeof(struct xtcpcb);
707ad4ed 1156 return (0);
984263bc
MD
1157 }
1158
707ad4ed
JH
1159 if (req->newptr != NULL)
1160 return (EPERM);
984263bc 1161
efda3bd0 1162 marker = kmalloc(sizeof(struct inpcb), M_TEMP, M_WAITOK|M_ZERO);
d2e9e54c
MD
1163 marker->inp_flags |= INP_PLACEMARKER;
1164
984263bc 1165 /*
d2e9e54c 1166 * OK, now we're committed to doing something. Run the inpcb list
f23061d4 1167 * for each cpu in the system and construct the output. Use a
d2e9e54c
MD
1168 * list placemarker to deal with list changes occuring during
1169 * copyout blockages (but otherwise depend on being on the correct
1170 * cpu to avoid races).
984263bc 1171 */
d2e9e54c
MD
1172 origcpu = mycpu->gd_cpuid;
1173 for (ccpu = 1; ccpu <= ncpus && error == 0; ++ccpu) {
1174 globaldata_t rgd;
1175 caddr_t inp_ppcb;
1176 struct xtcpcb xt;
1177 int cpu_id;
1178
1179 cpu_id = (origcpu + ccpu) % ncpus;
da23a592 1180 if ((smp_active_mask & CPUMASK(cpu_id)) == 0)
d2e9e54c
MD
1181 continue;
1182 rgd = globaldata_find(cpu_id);
1183 lwkt_setcpu_self(rgd);
1184
d2e9e54c
MD
1185 n = tcbinfo[cpu_id].ipi_count;
1186
d2e9e54c
MD
1187 LIST_INSERT_HEAD(&tcbinfo[cpu_id].pcblisthead, marker, inp_list);
1188 i = 0;
1189 while ((inp = LIST_NEXT(marker, inp_list)) != NULL && i < n) {
1190 /*
1191 * process a snapshot of pcbs, ignoring placemarkers
1192 * and using our own to allow SYSCTL_OUT to block.
1193 */
1194 LIST_REMOVE(marker, inp_list);
1195 LIST_INSERT_AFTER(inp, marker, inp_list);
707ad4ed 1196
d2e9e54c
MD
1197 if (inp->inp_flags & INP_PLACEMARKER)
1198 continue;
d2e9e54c
MD
1199 if (prison_xinpcb(req->td, inp))
1200 continue;
984263bc 1201
984263bc 1202 xt.xt_len = sizeof xt;
984263bc
MD
1203 bcopy(inp, &xt.xt_inp, sizeof *inp);
1204 inp_ppcb = inp->inp_ppcb;
1205 if (inp_ppcb != NULL)
1206 bcopy(inp_ppcb, &xt.xt_tp, sizeof xt.xt_tp);
1207 else
707ad4ed 1208 bzero(&xt.xt_tp, sizeof xt.xt_tp);
984263bc
MD
1209 if (inp->inp_socket)
1210 sotoxsocket(inp->inp_socket, &xt.xt_socket);
d2e9e54c
MD
1211 if ((error = SYSCTL_OUT(req, &xt, sizeof xt)) != 0)
1212 break;
1213 ++i;
1214 }
1215 LIST_REMOVE(marker, inp_list);
1216 if (error == 0 && i < n) {
0c3c561c
JH
1217 bzero(&xt, sizeof xt);
1218 xt.xt_len = sizeof xt;
d2e9e54c 1219 while (i < n) {
f23061d4 1220 error = SYSCTL_OUT(req, &xt, sizeof xt);
d2e9e54c
MD
1221 if (error)
1222 break;
1223 ++i;
1224 }
1225 }
984263bc 1226 }
d2e9e54c
MD
1227
1228 /*
1229 * Make sure we are on the same cpu we were on originally, since
1230 * higher level callers expect this. Also don't pollute caches with
1231 * migrated userland data by (eventually) returning to userland
1232 * on a different cpu.
1233 */
1234 lwkt_setcpu_self(globaldata_find(origcpu));
efda3bd0 1235 kfree(marker, M_TEMP);
707ad4ed 1236 return (error);
984263bc
MD
1237}
1238
1239SYSCTL_PROC(_net_inet_tcp, TCPCTL_PCBLIST, pcblist, CTLFLAG_RD, 0, 0,
1240 tcp_pcblist, "S,xtcpcb", "List of active TCP connections");
1241
1242static int
1243tcp_getcred(SYSCTL_HANDLER_ARGS)
1244{
1245 struct sockaddr_in addrs[2];
1246 struct inpcb *inp;
d371a63a 1247 int cpu;
1cae611f 1248 int error;
984263bc 1249
895c1f85 1250 error = priv_check(req->td, PRIV_ROOT);
707ad4ed 1251 if (error != 0)
984263bc 1252 return (error);
707ad4ed
JH
1253 error = SYSCTL_IN(req, addrs, sizeof addrs);
1254 if (error != 0)
984263bc 1255 return (error);
1cae611f 1256 crit_enter();
d371a63a
JH
1257 cpu = tcp_addrcpu(addrs[1].sin_addr.s_addr, addrs[1].sin_port,
1258 addrs[0].sin_addr.s_addr, addrs[0].sin_port);
1259 inp = in_pcblookup_hash(&tcbinfo[cpu], addrs[1].sin_addr,
1260 addrs[1].sin_port, addrs[0].sin_addr, addrs[0].sin_port, 0, NULL);
984263bc
MD
1261 if (inp == NULL || inp->inp_socket == NULL) {
1262 error = ENOENT;
1263 goto out;
1264 }
1265 error = SYSCTL_OUT(req, inp->inp_socket->so_cred, sizeof(struct ucred));
1266out:
1cae611f 1267 crit_exit();
984263bc
MD
1268 return (error);
1269}
1270
707ad4ed 1271SYSCTL_PROC(_net_inet_tcp, OID_AUTO, getcred, (CTLTYPE_OPAQUE | CTLFLAG_RW),
984263bc
MD
1272 0, 0, tcp_getcred, "S,ucred", "Get the ucred of a TCP connection");
1273
1274#ifdef INET6
1275static int
1276tcp6_getcred(SYSCTL_HANDLER_ARGS)
1277{
1278 struct sockaddr_in6 addrs[2];
1279 struct inpcb *inp;
1cae611f 1280 int error;
707ad4ed 1281 boolean_t mapped = FALSE;
984263bc 1282
895c1f85 1283 error = priv_check(req->td, PRIV_ROOT);
707ad4ed 1284 if (error != 0)
984263bc 1285 return (error);
707ad4ed
JH
1286 error = SYSCTL_IN(req, addrs, sizeof addrs);
1287 if (error != 0)
984263bc
MD
1288 return (error);
1289 if (IN6_IS_ADDR_V4MAPPED(&addrs[0].sin6_addr)) {
1290 if (IN6_IS_ADDR_V4MAPPED(&addrs[1].sin6_addr))
707ad4ed 1291 mapped = TRUE;
984263bc
MD
1292 else
1293 return (EINVAL);
1294 }
1cae611f 1295 crit_enter();
707ad4ed 1296 if (mapped) {
d371a63a
JH
1297 inp = in_pcblookup_hash(&tcbinfo[0],
1298 *(struct in_addr *)&addrs[1].sin6_addr.s6_addr[12],
1299 addrs[1].sin6_port,
1300 *(struct in_addr *)&addrs[0].sin6_addr.s6_addr[12],
1301 addrs[0].sin6_port,
1302 0, NULL);
1303 } else {
1304 inp = in6_pcblookup_hash(&tcbinfo[0],
1305 &addrs[1].sin6_addr, addrs[1].sin6_port,
1306 &addrs[0].sin6_addr, addrs[0].sin6_port,
1307 0, NULL);
1308 }
984263bc
MD
1309 if (inp == NULL || inp->inp_socket == NULL) {
1310 error = ENOENT;
1311 goto out;
1312 }
707ad4ed 1313 error = SYSCTL_OUT(req, inp->inp_socket->so_cred, sizeof(struct ucred));
984263bc 1314out:
1cae611f 1315 crit_exit();
984263bc
MD
1316 return (error);
1317}
1318
707ad4ed 1319SYSCTL_PROC(_net_inet6_tcp6, OID_AUTO, getcred, (CTLTYPE_OPAQUE | CTLFLAG_RW),
984263bc
MD
1320 0, 0,
1321 tcp6_getcred, "S,ucred", "Get the ucred of a TCP6 connection");
1322#endif
1323
14572273 1324struct netmsg_tcp_notify {
002c1265 1325 struct netmsg_base base;
14572273
SZ
1326 void (*nm_notify)(struct inpcb *, int);
1327 struct in_addr nm_faddr;
1328 int nm_arg;
1329};
1330
1331static void
002c1265 1332tcp_notifyall_oncpu(netmsg_t msg)
14572273 1333{
002c1265 1334 struct netmsg_tcp_notify *nm = (struct netmsg_tcp_notify *)msg;
14572273
SZ
1335 int nextcpu;
1336
002c1265
MD
1337 in_pcbnotifyall(&tcbinfo[mycpuid].pcblisthead, nm->nm_faddr,
1338 nm->nm_arg, nm->nm_notify);
14572273
SZ
1339
1340 nextcpu = mycpuid + 1;
1341 if (nextcpu < ncpus2)
3abced87 1342 lwkt_forwardmsg(netisr_portfn(nextcpu), &nm->base.lmsg);
14572273 1343 else
002c1265 1344 lwkt_replymsg(&nm->base.lmsg, 0);
14572273
SZ
1345}
1346
984263bc 1347void
002c1265 1348tcp_ctlinput(netmsg_t msg)
984263bc 1349{
002c1265
MD
1350 int cmd = msg->ctlinput.nm_cmd;
1351 struct sockaddr *sa = msg->ctlinput.nm_arg;
1352 struct ip *ip = msg->ctlinput.nm_extra;
984263bc
MD
1353 struct tcphdr *th;
1354 struct in_addr faddr;
1355 struct inpcb *inp;
1356 struct tcpcb *tp;
707ad4ed 1357 void (*notify)(struct inpcb *, int) = tcp_notify;
7d448528 1358 tcp_seq icmpseq;
1cae611f 1359 int arg, cpu;
7d448528
JH
1360
1361 if ((unsigned)cmd >= PRC_NCMDS || inetctlerrmap[cmd] == 0) {
002c1265 1362 goto done;
7d448528 1363 }
984263bc
MD
1364
1365 faddr = ((struct sockaddr_in *)sa)->sin_addr;
1366 if (sa->sa_family != AF_INET || faddr.s_addr == INADDR_ANY)
002c1265 1367 goto done;
984263bc 1368
7d448528
JH
1369 arg = inetctlerrmap[cmd];
1370 if (cmd == PRC_QUENCH) {
984263bc 1371 notify = tcp_quench;
7d448528
JH
1372 } else if (icmp_may_rst &&
1373 (cmd == PRC_UNREACH_ADMIN_PROHIB ||
1374 cmd == PRC_UNREACH_PORT ||
1375 cmd == PRC_TIMXCEED_INTRANS) &&
1376 ip != NULL) {
984263bc 1377 notify = tcp_drop_syn_sent;
7d448528
JH
1378 } else if (cmd == PRC_MSGSIZE) {
1379 struct icmp *icmp = (struct icmp *)
1380 ((caddr_t)ip - offsetof(struct icmp, icmp_ip));
1381
1382 arg = ntohs(icmp->icmp_nextmtu);
984263bc 1383 notify = tcp_mtudisc;
7d448528 1384 } else if (PRC_IS_REDIRECT(cmd)) {
707ad4ed 1385 ip = NULL;
984263bc 1386 notify = in_rtchange;
7d448528 1387 } else if (cmd == PRC_HOSTDEAD) {
707ad4ed 1388 ip = NULL;
7d448528
JH
1389 }
1390
707ad4ed 1391 if (ip != NULL) {
1cae611f 1392 crit_enter();
707ad4ed
JH
1393 th = (struct tcphdr *)((caddr_t)ip +
1394 (IP_VHL_HL(ip->ip_vhl) << 2));
d371a63a 1395 cpu = tcp_addrcpu(faddr.s_addr, th->th_dport,
707ad4ed 1396 ip->ip_src.s_addr, th->th_sport);
d371a63a 1397 inp = in_pcblookup_hash(&tcbinfo[cpu], faddr, th->th_dport,
707ad4ed
JH
1398 ip->ip_src, th->th_sport, 0, NULL);
1399 if ((inp != NULL) && (inp->inp_socket != NULL)) {
7d448528 1400 icmpseq = htonl(th->th_seq);
984263bc 1401 tp = intotcpcb(inp);
7d448528
JH
1402 if (SEQ_GEQ(icmpseq, tp->snd_una) &&
1403 SEQ_LT(icmpseq, tp->snd_max))
1404 (*notify)(inp, arg);
984263bc
MD
1405 } else {
1406 struct in_conninfo inc;
1407
1408 inc.inc_fport = th->th_dport;
1409 inc.inc_lport = th->th_sport;
1410 inc.inc_faddr = faddr;
1411 inc.inc_laddr = ip->ip_src;
1412#ifdef INET6
1413 inc.inc_isipv6 = 0;
1414#endif
1415 syncache_unreach(&inc, th);
1416 }
1cae611f 1417 crit_exit();
d371a63a 1418 } else {
002c1265 1419 struct netmsg_tcp_notify *nm;
14572273 1420
3abced87 1421 KKASSERT(&curthread->td_msgport == netisr_portfn(0));
002c1265
MD
1422 nm = kmalloc(sizeof(*nm), M_LWKTMSG, M_INTWAIT);
1423 netmsg_init(&nm->base, NULL, &netisr_afree_rport,
48e7b118 1424 0, tcp_notifyall_oncpu);
002c1265
MD
1425 nm->nm_faddr = faddr;
1426 nm->nm_arg = arg;
1427 nm->nm_notify = notify;
14572273 1428
3abced87 1429 lwkt_sendmsg(netisr_portfn(0), &nm->base.lmsg);
d371a63a 1430 }
002c1265
MD
1431done:
1432 lwkt_replymsg(&msg->lmsg, 0);
984263bc
MD
1433}
1434
1435#ifdef INET6
002c1265 1436
984263bc 1437void
002c1265 1438tcp6_ctlinput(netmsg_t msg)
984263bc 1439{
002c1265
MD
1440 int cmd = msg->ctlinput.nm_cmd;
1441 struct sockaddr *sa = msg->ctlinput.nm_arg;
1442 void *d = msg->ctlinput.nm_extra;
984263bc 1443 struct tcphdr th;
42a7fc75 1444 void (*notify) (struct inpcb *, int) = tcp_notify;
984263bc
MD
1445 struct ip6_hdr *ip6;
1446 struct mbuf *m;
1447 struct ip6ctlparam *ip6cp = NULL;
1448 const struct sockaddr_in6 *sa6_src = NULL;
1449 int off;
1450 struct tcp_portonly {
1451 u_int16_t th_sport;
1452 u_int16_t th_dport;
1453 } *thp;
7d448528 1454 int arg;
984263bc
MD
1455
1456 if (sa->sa_family != AF_INET6 ||
002c1265
MD
1457 sa->sa_len != sizeof(struct sockaddr_in6)) {
1458 goto out;
1459 }
984263bc 1460
7d448528 1461 arg = 0;
984263bc
MD
1462 if (cmd == PRC_QUENCH)
1463 notify = tcp_quench;
7d448528
JH
1464 else if (cmd == PRC_MSGSIZE) {
1465 struct ip6ctlparam *ip6cp = d;
1466 struct icmp6_hdr *icmp6 = ip6cp->ip6c_icmp6;
1467
1468 arg = ntohl(icmp6->icmp6_mtu);
984263bc 1469 notify = tcp_mtudisc;
7d448528
JH
1470 } else if (!PRC_IS_REDIRECT(cmd) &&
1471 ((unsigned)cmd > PRC_NCMDS || inet6ctlerrmap[cmd] == 0)) {
002c1265 1472 goto out;
7d448528 1473 }
984263bc
MD
1474
1475 /* if the parameter is from icmp6, decode it. */
1476 if (d != NULL) {
1477 ip6cp = (struct ip6ctlparam *)d;
1478 m = ip6cp->ip6c_m;
1479 ip6 = ip6cp->ip6c_ip6;
1480 off = ip6cp->ip6c_off;
1481 sa6_src = ip6cp->ip6c_src;
1482 } else {
1483 m = NULL;
1484 ip6 = NULL;
1485 off = 0; /* fool gcc */
1486 sa6_src = &sa6_any;
1487 }
1488
707ad4ed 1489 if (ip6 != NULL) {
984263bc
MD
1490 struct in_conninfo inc;
1491 /*
1492 * XXX: We assume that when IPV6 is non NULL,
1493 * M and OFF are valid.
1494 */
1495
1496 /* check if we can safely examine src and dst ports */
707ad4ed 1497 if (m->m_pkthdr.len < off + sizeof *thp)
002c1265 1498 goto out;
984263bc 1499
707ad4ed
JH
1500 bzero(&th, sizeof th);
1501 m_copydata(m, off, sizeof *thp, (caddr_t)&th);
984263bc 1502
d2e9e54c 1503 in6_pcbnotify(&tcbinfo[0].pcblisthead, sa, th.th_dport,
984263bc 1504 (struct sockaddr *)ip6cp->ip6c_src,
7d448528 1505 th.th_sport, cmd, arg, notify);
984263bc
MD
1506
1507 inc.inc_fport = th.th_dport;
1508 inc.inc_lport = th.th_sport;
1509 inc.inc6_faddr = ((struct sockaddr_in6 *)sa)->sin6_addr;
1510 inc.inc6_laddr = ip6cp->ip6c_src->sin6_addr;
1511 inc.inc_isipv6 = 1;
1512 syncache_unreach(&inc, &th);
002c1265 1513 } else {
d2e9e54c 1514 in6_pcbnotify(&tcbinfo[0].pcblisthead, sa, 0,
7d448528 1515 (const struct sockaddr *)sa6_src, 0, cmd, arg, notify);
002c1265
MD
1516 }
1517out:
1518 lwkt_replymsg(&msg->ctlinput.base.lmsg, 0);
984263bc 1519}
002c1265 1520
707ad4ed 1521#endif
984263bc
MD
1522
1523/*
1524 * Following is where TCP initial sequence number generation occurs.
1525 *
1526 * There are two places where we must use initial sequence numbers:
1527 * 1. In SYN-ACK packets.
1528 * 2. In SYN packets.
1529 *
1530 * All ISNs for SYN-ACK packets are generated by the syncache. See
1531 * tcp_syncache.c for details.
1532 *
1533 * The ISNs in SYN packets must be monotonic; TIME_WAIT recycling
1534 * depends on this property. In addition, these ISNs should be
1535 * unguessable so as to prevent connection hijacking. To satisfy
1536 * the requirements of this situation, the algorithm outlined in
1537 * RFC 1948 is used to generate sequence numbers.
1538 *
1539 * Implementation details:
1540 *
1541 * Time is based off the system timer, and is corrected so that it
1542 * increases by one megabyte per second. This allows for proper
1543 * recycling on high speed LANs while still leaving over an hour
1544 * before rollover.
1545 *
1546 * net.inet.tcp.isn_reseed_interval controls the number of seconds
1547 * between seeding of isn_secret. This is normally set to zero,
1548 * as reseeding should not be necessary.
1549 *
1550 */
1551
707ad4ed 1552#define ISN_BYTES_PER_SECOND 1048576
984263bc
MD
1553
1554u_char isn_secret[32];
1555int isn_last_reseed;
1556MD5_CTX isn_ctx;
1557
1558tcp_seq
707ad4ed 1559tcp_new_isn(struct tcpcb *tp)
984263bc
MD
1560{
1561 u_int32_t md5_buffer[4];
1562 tcp_seq new_isn;
1563
1564 /* Seed if this is the first use, reseed if requested. */
1565 if ((isn_last_reseed == 0) || ((tcp_isn_reseed_interval > 0) &&
1566 (((u_int)isn_last_reseed + (u_int)tcp_isn_reseed_interval*hz)
1567 < (u_int)ticks))) {
707ad4ed 1568 read_random_unlimited(&isn_secret, sizeof isn_secret);
984263bc
MD
1569 isn_last_reseed = ticks;
1570 }
707ad4ed 1571
984263bc
MD
1572 /* Compute the md5 hash and return the ISN. */
1573 MD5Init(&isn_ctx);
707ad4ed
JH
1574 MD5Update(&isn_ctx, (u_char *)&tp->t_inpcb->inp_fport, sizeof(u_short));
1575 MD5Update(&isn_ctx, (u_char *)&tp->t_inpcb->inp_lport, sizeof(u_short));
984263bc 1576#ifdef INET6
707ad4ed 1577 if (tp->t_inpcb->inp_vflag & INP_IPV6) {
984263bc
MD
1578 MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->in6p_faddr,
1579 sizeof(struct in6_addr));
1580 MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->in6p_laddr,
1581 sizeof(struct in6_addr));
1582 } else
1583#endif
1584 {
1585 MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->inp_faddr,
1586 sizeof(struct in_addr));
1587 MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->inp_laddr,
1588 sizeof(struct in_addr));
1589 }
1590 MD5Update(&isn_ctx, (u_char *) &isn_secret, sizeof(isn_secret));
1591 MD5Final((u_char *) &md5_buffer, &isn_ctx);
1592 new_isn = (tcp_seq) md5_buffer[0];
1593 new_isn += ticks * (ISN_BYTES_PER_SECOND / hz);
707ad4ed 1594 return (new_isn);
984263bc
MD
1595}
1596
1597/*
1598 * When a source quench is received, close congestion window
1599 * to one segment. We will gradually open it again as we proceed.
1600 */
1601void
71f385dc 1602tcp_quench(struct inpcb *inp, int error)
984263bc
MD
1603{
1604 struct tcpcb *tp = intotcpcb(inp);
1605
8acdb67c 1606 if (tp != NULL) {
984263bc 1607 tp->snd_cwnd = tp->t_maxseg;
8acdb67c
JH
1608 tp->snd_wacked = 0;
1609 }
984263bc
MD
1610}
1611
1612/*
1613 * When a specific ICMP unreachable message is received and the
1614 * connection state is SYN-SENT, drop the connection. This behavior
1615 * is controlled by the icmp_may_rst sysctl.
1616 */
1617void
71f385dc 1618tcp_drop_syn_sent(struct inpcb *inp, int error)
984263bc
MD
1619{
1620 struct tcpcb *tp = intotcpcb(inp);
1621
707ad4ed 1622 if ((tp != NULL) && (tp->t_state == TCPS_SYN_SENT))
71f385dc 1623 tcp_drop(tp, error);
984263bc
MD
1624}
1625
1626/*
7d448528 1627 * When a `need fragmentation' ICMP is received, update our idea of the MSS
984263bc
MD
1628 * based on the new value in the route. Also nudge TCP to send something,
1629 * since we know the packet we just sent was dropped.
1630 * This duplicates some code in the tcp_mss() function in tcp_input.c.
1631 */
1632void
7d448528 1633tcp_mtudisc(struct inpcb *inp, int mtu)
984263bc
MD
1634{
1635 struct tcpcb *tp = intotcpcb(inp);
1636 struct rtentry *rt;
984263bc 1637 struct socket *so = inp->inp_socket;
7d448528 1638 int maxopd, mss;
984263bc 1639#ifdef INET6
707ad4ed
JH
1640 boolean_t isipv6 = ((tp->t_inpcb->inp_vflag & INP_IPV6) != 0);
1641#else
1642 const boolean_t isipv6 = FALSE;
1643#endif
984263bc 1644
7d448528
JH
1645 if (tp == NULL)
1646 return;
1647
1648 /*
1649 * If no MTU is provided in the ICMP message, use the
1650 * next lower likely value, as specified in RFC 1191.
1651 */
1652 if (mtu == 0) {
1653 int oldmtu;
1654
1655 oldmtu = tp->t_maxopd +
1656 (isipv6 ?
1657 sizeof(struct ip6_hdr) + sizeof(struct tcphdr) :
1658 sizeof(struct tcpiphdr));
1659 mtu = ip_next_mtu(oldmtu, 0);
1660 }
1661
1662 if (isipv6)
1663 rt = tcp_rtlookup6(&inp->inp_inc);
1664 else
1665 rt = tcp_rtlookup(&inp->inp_inc);
1666 if (rt != NULL) {
7d448528
JH
1667 if (rt->rt_rmx.rmx_mtu != 0 && rt->rt_rmx.rmx_mtu < mtu)
1668 mtu = rt->rt_rmx.rmx_mtu;
1669
1670 maxopd = mtu -
1671 (isipv6 ?
1672 sizeof(struct ip6_hdr) + sizeof(struct tcphdr) :
1673 sizeof(struct tcpiphdr));
1674
984263bc 1675 /*
7d448528 1676 * XXX - The following conditional probably violates the TCP
984263bc
MD
1677 * spec. The problem is that, since we don't know the
1678 * other end's MSS, we are supposed to use a conservative
1679 * default. But, if we do that, then MTU discovery will
1680 * never actually take place, because the conservative
1681 * default is much less than the MTUs typically seen
1682 * on the Internet today. For the moment, we'll sweep
1683 * this under the carpet.
1684 *
1685 * The conservative default might not actually be a problem
1686 * if the only case this occurs is when sending an initial
1687 * SYN with options and data to a host we've never talked
1688 * to before. Then, they will reply with an MSS value which
1689 * will get recorded and the new parameters should get
1690 * recomputed. For Further Study.
1691 */
27b8aee3
AE
1692 if (rt->rt_rmx.rmx_mssopt && rt->rt_rmx.rmx_mssopt < maxopd)
1693 maxopd = rt->rt_rmx.rmx_mssopt;
7d448528
JH
1694 } else
1695 maxopd = mtu -
1696 (isipv6 ?
1697 sizeof(struct ip6_hdr) + sizeof(struct tcphdr) :
1698 sizeof(struct tcpiphdr));
1699
1700 if (tp->t_maxopd <= maxopd)
1701 return;
1702 tp->t_maxopd = maxopd;
1703
1704 mss = maxopd;
1705 if ((tp->t_flags & (TF_REQ_TSTMP | TF_RCVD_TSTMP | TF_NOOPT)) ==
1706 (TF_REQ_TSTMP | TF_RCVD_TSTMP))
1707 mss -= TCPOLEN_TSTAMP_APPA;
1708
7d448528
JH
1709 /* round down to multiple of MCLBYTES */
1710#if (MCLBYTES & (MCLBYTES - 1)) == 0 /* test if MCLBYTES power of 2 */
1711 if (mss > MCLBYTES)
1712 mss &= ~(MCLBYTES - 1);
984263bc 1713#else
7d448528
JH
1714 if (mss > MCLBYTES)
1715 mss = (mss / MCLBYTES) * MCLBYTES;
984263bc 1716#endif
984263bc 1717
6d49aa6f
MD
1718 if (so->so_snd.ssb_hiwat < mss)
1719 mss = so->so_snd.ssb_hiwat;
984263bc 1720
7d448528
JH
1721 tp->t_maxseg = mss;
1722 tp->t_rtttime = 0;
1723 tp->snd_nxt = tp->snd_una;
1724 tcp_output(tp);
1725 tcpstat.tcps_mturesent++;
984263bc
MD
1726}
1727
1728/*
1729 * Look-up the routing entry to the peer of this inpcb. If no route
1730 * is found and it cannot be allocated the return NULL. This routine
1731 * is called by TCP routines that access the rmx structure and by tcp_mss
1732 * to get the interface MTU.
1733 */
1734struct rtentry *
707ad4ed 1735tcp_rtlookup(struct in_conninfo *inc)
984263bc 1736{
f23061d4 1737 struct route *ro = &inc->inc_route;
984263bc 1738
f23061d4 1739 if (ro->ro_rt == NULL || !(ro->ro_rt->rt_flags & RTF_UP)) {
984263bc
MD
1740 /* No route yet, so try to acquire one */
1741 if (inc->inc_faddr.s_addr != INADDR_ANY) {
88fcebeb
MD
1742 /*
1743 * unused portions of the structure MUST be zero'd
1744 * out because rtalloc() treats it as opaque data
1745 */
1746 bzero(&ro->ro_dst, sizeof(struct sockaddr_in));
984263bc
MD
1747 ro->ro_dst.sa_family = AF_INET;
1748 ro->ro_dst.sa_len = sizeof(struct sockaddr_in);
1749 ((struct sockaddr_in *) &ro->ro_dst)->sin_addr =
1750 inc->inc_faddr;
1751 rtalloc(ro);
984263bc
MD
1752 }
1753 }
f23061d4 1754 return (ro->ro_rt);
984263bc
MD
1755}
1756
1757#ifdef INET6
1758struct rtentry *
707ad4ed 1759tcp_rtlookup6(struct in_conninfo *inc)
984263bc 1760{
f23061d4 1761 struct route_in6 *ro6 = &inc->inc6_route;
984263bc 1762
f23061d4 1763 if (ro6->ro_rt == NULL || !(ro6->ro_rt->rt_flags & RTF_UP)) {
984263bc
MD
1764 /* No route yet, so try to acquire one */
1765 if (!IN6_IS_ADDR_UNSPECIFIED(&inc->inc6_faddr)) {
88fcebeb
MD
1766 /*
1767 * unused portions of the structure MUST be zero'd
1768 * out because rtalloc() treats it as opaque data
1769 */
1770 bzero(&ro6->ro_dst, sizeof(struct sockaddr_in6));
984263bc
MD
1771 ro6->ro_dst.sin6_family = AF_INET6;
1772 ro6->ro_dst.sin6_len = sizeof(struct sockaddr_in6);
1773 ro6->ro_dst.sin6_addr = inc->inc6_faddr;
1774 rtalloc((struct route *)ro6);
984263bc
MD
1775 }
1776 }
f23061d4 1777 return (ro6->ro_rt);
984263bc 1778}
707ad4ed 1779#endif
984263bc
MD
1780
1781#ifdef IPSEC
1782/* compute ESP/AH header size for TCP, including outer IP header. */
1783size_t
707ad4ed 1784ipsec_hdrsiz_tcp(struct tcpcb *tp)
984263bc
MD
1785{
1786 struct inpcb *inp;
1787 struct mbuf *m;
1788 size_t hdrsiz;
1789 struct ip *ip;
984263bc
MD
1790 struct tcphdr *th;
1791
1792 if ((tp == NULL) || ((inp = tp->t_inpcb) == NULL))
707ad4ed 1793 return (0);
74f1caca 1794 MGETHDR(m, MB_DONTWAIT, MT_DATA);
984263bc 1795 if (!m)
707ad4ed 1796 return (0);
984263bc
MD
1797
1798#ifdef INET6
707ad4ed
JH
1799 if (inp->inp_vflag & INP_IPV6) {
1800 struct ip6_hdr *ip6 = mtod(m, struct ip6_hdr *);
1801
984263bc
MD
1802 th = (struct tcphdr *)(ip6 + 1);
1803 m->m_pkthdr.len = m->m_len =
707ad4ed 1804 sizeof(struct ip6_hdr) + sizeof(struct tcphdr);
5f60906c 1805 tcp_fillheaders(tp, ip6, th, FALSE);
984263bc
MD
1806 hdrsiz = ipsec6_hdrsiz(m, IPSEC_DIR_OUTBOUND, inp);
1807 } else
707ad4ed
JH
1808#endif
1809 {
1810 ip = mtod(m, struct ip *);
1811 th = (struct tcphdr *)(ip + 1);
1812 m->m_pkthdr.len = m->m_len = sizeof(struct tcpiphdr);
5f60906c 1813 tcp_fillheaders(tp, ip, th, FALSE);
707ad4ed
JH
1814 hdrsiz = ipsec4_hdrsiz(m, IPSEC_DIR_OUTBOUND, inp);
1815 }
984263bc
MD
1816
1817 m_free(m);
707ad4ed 1818 return (hdrsiz);
984263bc 1819}
707ad4ed 1820#endif
984263bc 1821
984263bc
MD
1822/*
1823 * TCP BANDWIDTH DELAY PRODUCT WINDOW LIMITING
1824 *
1825 * This code attempts to calculate the bandwidth-delay product as a
1826 * means of determining the optimal window size to maximize bandwidth,
1827 * minimize RTT, and avoid the over-allocation of buffers on interfaces and
1828 * routers. This code also does a fairly good job keeping RTTs in check
1829 * across slow links like modems. We implement an algorithm which is very
1830 * similar (but not meant to be) TCP/Vegas. The code operates on the
1831 * transmitter side of a TCP connection and so only effects the transmit
1832 * side of the connection.
1833 *
1834 * BACKGROUND: TCP makes no provision for the management of buffer space
f23061d4 1835 * at the end points or at the intermediate routers and switches. A TCP
984263bc
MD
1836 * stream, whether using NewReno or not, will eventually buffer as
1837 * many packets as it is able and the only reason this typically works is
1838 * due to the fairly small default buffers made available for a connection
1839 * (typicaly 16K or 32K). As machines use larger windows and/or window
1840 * scaling it is now fairly easy for even a single TCP connection to blow-out
f23061d4 1841 * all available buffer space not only on the local interface, but on
984263bc
MD
1842 * intermediate routers and switches as well. NewReno makes a misguided
1843 * attempt to 'solve' this problem by waiting for an actual failure to occur,
1844 * then backing off, then steadily increasing the window again until another
1845 * failure occurs, ad-infinitum. This results in terrible oscillation that
1846 * is only made worse as network loads increase and the idea of intentionally
1847 * blowing out network buffers is, frankly, a terrible way to manage network
1848 * resources.
1849 *
1850 * It is far better to limit the transmit window prior to the failure
1851 * condition being achieved. There are two general ways to do this: First
1852 * you can 'scan' through different transmit window sizes and locate the
1853 * point where the RTT stops increasing, indicating that you have filled the
1854 * pipe, then scan backwards until you note that RTT stops decreasing, then
1855 * repeat ad-infinitum. This method works in principle but has severe
1856 * implementation issues due to RTT variances, timer granularity, and
1857 * instability in the algorithm which can lead to many false positives and
1858 * create oscillations as well as interact badly with other TCP streams
1859 * implementing the same algorithm.
1860 *
1861 * The second method is to limit the window to the bandwidth delay product
1862 * of the link. This is the method we implement. RTT variances and our
f23061d4 1863 * own manipulation of the congestion window, bwnd, can potentially
984263bc
MD
1864 * destabilize the algorithm. For this reason we have to stabilize the
1865 * elements used to calculate the window. We do this by using the minimum
1866 * observed RTT, the long term average of the observed bandwidth, and
1867 * by adding two segments worth of slop. It isn't perfect but it is able
1868 * to react to changing conditions and gives us a very stable basis on
1869 * which to extend the algorithm.
1870 */
1871void
1872tcp_xmit_bandwidth_limit(struct tcpcb *tp, tcp_seq ack_seq)
1873{
1874 u_long bw;
1875 u_long bwnd;
1876 int save_ticks;
421de19e 1877 int delta_ticks;
984263bc
MD
1878
1879 /*
1880 * If inflight_enable is disabled in the middle of a tcp connection,
1881 * make sure snd_bwnd is effectively disabled.
1882 */
707ad4ed 1883 if (!tcp_inflight_enable) {
984263bc
MD
1884 tp->snd_bwnd = TCP_MAXWIN << TCP_MAX_WINSHIFT;
1885 tp->snd_bandwidth = 0;
1886 return;
1887 }
1888
421de19e
MD
1889 /*
1890 * Validate the delta time. If a connection is new or has been idle
1891 * a long time we have to reset the bandwidth calculator.
1892 */
1893 save_ticks = ticks;
1894 delta_ticks = save_ticks - tp->t_bw_rtttime;
1895 if (tp->t_bw_rtttime == 0 || delta_ticks < 0 || delta_ticks > hz * 10) {
1896 tp->t_bw_rtttime = ticks;
1897 tp->t_bw_rtseq = ack_seq;
1898 if (tp->snd_bandwidth == 0)
1899 tp->snd_bandwidth = tcp_inflight_min;
1900 return;
1901 }
1902 if (delta_ticks == 0)
1903 return;
1904
1905 /*
1906 * Sanity check, plus ignore pure window update acks.
1907 */
1908 if ((int)(ack_seq - tp->t_bw_rtseq) <= 0)
1909 return;
1910
984263bc
MD
1911 /*
1912 * Figure out the bandwidth. Due to the tick granularity this
1913 * is a very rough number and it MUST be averaged over a fairly
1914 * long period of time. XXX we need to take into account a link
1915 * that is not using all available bandwidth, but for now our
1916 * slop will ramp us up if this case occurs and the bandwidth later
1917 * increases.
984263bc 1918 */
421de19e 1919 bw = (int64_t)(ack_seq - tp->t_bw_rtseq) * hz / delta_ticks;
984263bc
MD
1920 tp->t_bw_rtttime = save_ticks;
1921 tp->t_bw_rtseq = ack_seq;
984263bc
MD
1922 bw = ((int64_t)tp->snd_bandwidth * 15 + bw) >> 4;
1923
1924 tp->snd_bandwidth = bw;
1925
1926 /*
1927 * Calculate the semi-static bandwidth delay product, plus two maximal
1928 * segments. The additional slop puts us squarely in the sweet
1929 * spot and also handles the bandwidth run-up case. Without the
1930 * slop we could be locking ourselves into a lower bandwidth.
1931 *
1932 * Situations Handled:
1933 * (1) Prevents over-queueing of packets on LANs, especially on
1934 * high speed LANs, allowing larger TCP buffers to be
f23061d4 1935 * specified, and also does a good job preventing
984263bc
MD
1936 * over-queueing of packets over choke points like modems
1937 * (at least for the transmit side).
1938 *
1939 * (2) Is able to handle changing network loads (bandwidth
1940 * drops so bwnd drops, bandwidth increases so bwnd
1941 * increases).
1942 *
1943 * (3) Theoretically should stabilize in the face of multiple
1944 * connections implementing the same algorithm (this may need
1945 * a little work).
1946 *
f23061d4 1947 * (4) Stability value (defaults to 20 = 2 maximal packets) can
984263bc
MD
1948 * be adjusted with a sysctl but typically only needs to be on
1949 * very slow connections. A value no smaller then 5 should
1950 * be used, but only reduce this default if you have no other
1951 * choice.
1952 */
707ad4ed
JH
1953
1954#define USERTT ((tp->t_srtt + tp->t_rttbest) / 2)
1955 bwnd = (int64_t)bw * USERTT / (hz << TCP_RTT_SHIFT) +
1956 tcp_inflight_stab * (int)tp->t_maxseg / 10;
984263bc
MD
1957#undef USERTT
1958
1959 if (tcp_inflight_debug > 0) {
1960 static int ltime;
1961 if ((u_int)(ticks - ltime) >= hz / tcp_inflight_debug) {
1962 ltime = ticks;
a6ec04bc 1963 kprintf("%p bw %ld rttbest %d srtt %d bwnd %ld\n",
707ad4ed 1964 tp, bw, tp->t_rttbest, tp->t_srtt, bwnd);
984263bc
MD
1965 }
1966 }
1967 if ((long)bwnd < tcp_inflight_min)
1968 bwnd = tcp_inflight_min;
1969 if (bwnd > tcp_inflight_max)
1970 bwnd = tcp_inflight_max;
1971 if ((long)bwnd < tp->t_maxseg * 2)
1972 bwnd = tp->t_maxseg * 2;
1973 tp->snd_bwnd = bwnd;
1974}
b1992928 1975
c01148a3
SZ
1976static void
1977tcp_rmx_iwsegs(struct tcpcb *tp, u_long *maxsegs, u_long *capsegs)
1978{
1979 struct rtentry *rt;
1980 struct inpcb *inp = tp->t_inpcb;
1981#ifdef INET6
1982 boolean_t isipv6 = ((inp->inp_vflag & INP_IPV6) ? TRUE : FALSE);
1983#else
1984 const boolean_t isipv6 = FALSE;
1985#endif
1986
1987 /* XXX */
1988 if (tcp_iw_maxsegs < TCP_IW_MAXSEGS_DFLT)
1989 tcp_iw_maxsegs = TCP_IW_MAXSEGS_DFLT;
1990 if (tcp_iw_capsegs < TCP_IW_CAPSEGS_DFLT)
1991 tcp_iw_capsegs = TCP_IW_CAPSEGS_DFLT;
1992
1993 if (isipv6)
1994 rt = tcp_rtlookup6(&inp->inp_inc);
1995 else
1996 rt = tcp_rtlookup(&inp->inp_inc);
1997 if (rt == NULL ||
1998 rt->rt_rmx.rmx_iwmaxsegs < TCP_IW_MAXSEGS_DFLT ||
1999 rt->rt_rmx.rmx_iwcapsegs < TCP_IW_CAPSEGS_DFLT) {
2000 *maxsegs = tcp_iw_maxsegs;
2001 *capsegs = tcp_iw_capsegs;
2002 return;
2003 }
2004 *maxsegs = rt->rt_rmx.rmx_iwmaxsegs;
2005 *capsegs = rt->rt_rmx.rmx_iwcapsegs;
2006}
2007
697020f5 2008u_long
c01148a3 2009tcp_initial_window(struct tcpcb *tp)
697020f5 2010{
fa1b6ee4 2011 if (tcp_do_rfc3390) {
d5082e3d
SZ
2012 /*
2013 * RFC3390:
2014 * "If the SYN or SYN/ACK is lost, the initial window
2015 * used by a sender after a correctly transmitted SYN
2016 * MUST be one segment consisting of MSS bytes."
2017 *
2018 * However, we do something a little bit more aggressive
2019 * then RFC3390 here:
2020 * - Only if time spent in the SYN or SYN|ACK retransmition
2021 * >= 3 seconds, the IW is reduced. We do this mainly
2022 * because when RFC3390 is published, the initial RTO is
2023 * still 3 seconds (the threshold we test here), while
2024 * after RFC6298, the initial RTO is 1 second. This
2025 * behaviour probably still falls within the spirit of
2026 * RFC3390.
2027 * - When IW is reduced, 2*MSS is used instead of 1*MSS.
2028 * Mainly to avoid sender and receiver deadlock until
2029 * delayed ACK timer expires. And even RFC2581 does not
2030 * try to reduce IW upon SYN or SYN|ACK retransmition
2031 * timeout.
2032 *
2033 * See also:
2034 * http://tools.ietf.org/html/draft-ietf-tcpm-initcwnd-03
2035 */
2036 if (tp->t_rxtsyn >= TCPTV_RTOBASE3) {
2037 return (2 * tp->t_maxseg);
2038 } else {
c01148a3
SZ
2039 u_long maxsegs, capsegs;
2040
2041 tcp_rmx_iwsegs(tp, &maxsegs, &capsegs);
2042 return min(maxsegs * tp->t_maxseg,
2043 max(2 * tp->t_maxseg, capsegs * 1460));
d5082e3d 2044 }
fa1b6ee4
SZ
2045 } else {
2046 /*
2047 * Even RFC2581 (back to 1999) allows 2*SMSS IW.
2048 *
2049 * Mainly to avoid sender and receiver deadlock
2050 * until delayed ACK timer expires.
2051 */
2052 return (2 * tp->t_maxseg);
2053 }
697020f5
SZ
2054}
2055
b1992928
MD
2056#ifdef TCP_SIGNATURE
2057/*
2058 * Compute TCP-MD5 hash of a TCP segment. (RFC2385)
2059 *
2060 * We do this over ip, tcphdr, segment data, and the key in the SADB.
2061 * When called from tcp_input(), we can be sure that th_sum has been
2062 * zeroed out and verified already.
2063 *
2064 * Return 0 if successful, otherwise return -1.
2065 *
2066 * XXX The key is retrieved from the system's PF_KEY SADB, by keying a
2067 * search with the destination IP address, and a 'magic SPI' to be
2068 * determined by the application. This is hardcoded elsewhere to 1179
2069 * right now. Another branch of this code exists which uses the SPD to
2070 * specify per-application flows but it is unstable.
2071 */
2072int
2073tcpsignature_compute(
2074 struct mbuf *m, /* mbuf chain */
2075 int len, /* length of TCP data */
2076 int optlen, /* length of TCP options */
2077 u_char *buf, /* storage for MD5 digest */
2078 u_int direction) /* direction of flow */
2079{
2080 struct ippseudo ippseudo;
2081 MD5_CTX ctx;
2082 int doff;
2083 struct ip *ip;
2084 struct ipovly *ipovly;
2085 struct secasvar *sav;
2086 struct tcphdr *th;
2087#ifdef INET6
2088 struct ip6_hdr *ip6;
2089 struct in6_addr in6;
2090 uint32_t plen;
2091 uint16_t nhdr;
2092#endif /* INET6 */
2093 u_short savecsum;
2094
2095 KASSERT(m != NULL, ("passed NULL mbuf. Game over."));
2096 KASSERT(buf != NULL, ("passed NULL storage pointer for MD5 signature"));
2097 /*
2098 * Extract the destination from the IP header in the mbuf.
2099 */
2100 ip = mtod(m, struct ip *);
2101#ifdef INET6
2102 ip6 = NULL; /* Make the compiler happy. */
2103#endif /* INET6 */
2104 /*
2105 * Look up an SADB entry which matches the address found in
2106 * the segment.
2107 */
2108 switch (IP_VHL_V(ip->ip_vhl)) {
2109 case IPVERSION:
2110 sav = key_allocsa(AF_INET, (caddr_t)&ip->ip_src, (caddr_t)&ip->ip_dst,
2111 IPPROTO_TCP, htonl(TCP_SIG_SPI));
2112 break;
2113#ifdef INET6
2114 case (IPV6_VERSION >> 4):
2115 ip6 = mtod(m, struct ip6_hdr *);
2116 sav = key_allocsa(AF_INET6, (caddr_t)&ip6->ip6_src, (caddr_t)&ip6->ip6_dst,
2117 IPPROTO_TCP, htonl(TCP_SIG_SPI));
2118 break;
2119#endif /* INET6 */
2120 default:
2121 return (EINVAL);
2122 /* NOTREACHED */
2123 break;
2124 }
2125 if (sav == NULL) {
2126 kprintf("%s: SADB lookup failed\n", __func__);
2127 return (EINVAL);
2128 }
2129 MD5Init(&ctx);
2130
2131 /*
2132 * Step 1: Update MD5 hash with IP pseudo-header.
2133 *
2134 * XXX The ippseudo header MUST be digested in network byte order,
2135 * or else we'll fail the regression test. Assume all fields we've
2136 * been doing arithmetic on have been in host byte order.
2137 * XXX One cannot depend on ipovly->ih_len here. When called from
2138 * tcp_output(), the underlying ip_len member has not yet been set.
2139 */
2140 switch (IP_VHL_V(ip->ip_vhl)) {
2141 case IPVERSION:
2142 ipovly = (struct ipovly *)ip;
2143 ippseudo.ippseudo_src = ipovly->ih_src;
2144 ippseudo.ippseudo_dst = ipovly->ih_dst;
2145 ippseudo.ippseudo_pad = 0;
2146 ippseudo.ippseudo_p = IPPROTO_TCP;
2147 ippseudo.ippseudo_len = htons(len + sizeof(struct tcphdr) + optlen);
2148 MD5Update(&ctx, (char *)&ippseudo, sizeof(struct ippseudo));
2149 th = (struct tcphdr *)((u_char *)ip + sizeof(struct ip));
2150 doff = sizeof(struct ip) + sizeof(struct tcphdr) + optlen;
2151 break;
2152#ifdef INET6
2153 /*
2154 * RFC 2385, 2.0 Proposal
2155 * For IPv6, the pseudo-header is as described in RFC 2460, namely the
2156 * 128-bit source IPv6 address, 128-bit destination IPv6 address, zero-
2157 * extended next header value (to form 32 bits), and 32-bit segment
2158 * length.
2159 * Note: Upper-Layer Packet Length comes before Next Header.
2160 */
2161 case (IPV6_VERSION >> 4):
2162 in6 = ip6->ip6_src;
2163 in6_clearscope(&in6);
2164 MD5Update(&ctx, (char *)&in6, sizeof(struct in6_addr));
2165 in6 = ip6->ip6_dst;
2166 in6_clearscope(&in6);
2167 MD5Update(&ctx, (char *)&in6, sizeof(struct in6_addr));
2168 plen = htonl(len + sizeof(struct tcphdr) + optlen);
2169 MD5Update(&ctx, (char *)&plen, sizeof(uint32_t));
2170 nhdr = 0;
2171 MD5Update(&ctx, (char *)&nhdr, sizeof(uint8_t));
2172 MD5Update(&ctx, (char *)&nhdr, sizeof(uint8_t));
2173 MD5Update(&ctx, (char *)&nhdr, sizeof(uint8_t));
2174 nhdr = IPPROTO_TCP;
2175 MD5Update(&ctx, (char *)&nhdr, sizeof(uint8_t));
2176 th = (struct tcphdr *)((u_char *)ip6 + sizeof(struct ip6_hdr));
2177 doff = sizeof(struct ip6_hdr) + sizeof(struct tcphdr) + optlen;
2178 break;
2179#endif /* INET6 */
2180 default:
2181 return (EINVAL);
2182 /* NOTREACHED */
2183 break;
2184 }
2185 /*
2186 * Step 2: Update MD5 hash with TCP header, excluding options.
2187 * The TCP checksum must be set to zero.
2188 */
2189 savecsum = th->th_sum;
2190 th->th_sum = 0;
2191 MD5Update(&ctx, (char *)th, sizeof(struct tcphdr));
2192 th->th_sum = savecsum;
2193 /*
2194 * Step 3: Update MD5 hash with TCP segment data.
2195 * Use m_apply() to avoid an early m_pullup().
2196 */
2197 if (len > 0)
2198 m_apply(m, doff, len, tcpsignature_apply, &ctx);
2199 /*
2200 * Step 4: Update MD5 hash with shared secret.
2201 */
2202 MD5Update(&ctx, _KEYBUF(sav->key_auth), _KEYLEN(sav->key_auth));
2203 MD5Final(buf, &ctx);
2204 key_sa_recordxfer(sav, m);
2205 key_freesav(sav);
2206 return (0);
2207}
2208
2209int
2210tcpsignature_apply(void *fstate, void *data, unsigned int len)
2211{
2212
2213 MD5Update((MD5_CTX *)fstate, (unsigned char *)data, len);
2214 return (0);
2215}
2216#endif /* TCP_SIGNATURE */
5f60906c
SZ
2217
2218boolean_t
2219tcp_tso_pullup(struct mbuf **mp, int hoff, struct ip **ip0, int *iphlen0,
2220 struct tcphdr **th0, int *thoff0)
2221{
2222 struct mbuf *m = *mp;
2223 struct ip *ip;
2224 int len, iphlen;
2225 struct tcphdr *th;
2226 int thoff;
2227
2228 len = hoff + sizeof(struct ip);
2229
2230 /* The fixed IP header must reside completely in the first mbuf. */
2231 if (m->m_len < len) {
2232 m = m_pullup(m, len);
2233 if (m == NULL)
2234 goto fail;
2235 }
2236
2237 ip = mtodoff(m, struct ip *, hoff);
2238 iphlen = IP_VHL_HL(ip->ip_vhl) << 2;
2239
2240 /* The full IP header must reside completely in the one mbuf. */
2241 if (m->m_len < hoff + iphlen) {
2242 m = m_pullup(m, hoff + iphlen);
2243 if (m == NULL)
2244 goto fail;
2245 ip = mtodoff(m, struct ip *, hoff);
2246 }
2247
2248 KASSERT(ip->ip_p == IPPROTO_TCP, ("not tcp %d", ip->ip_p));
2249
2250 if (m->m_len < hoff + iphlen + sizeof(struct tcphdr)) {
2251 m = m_pullup(m, hoff + iphlen + sizeof(struct tcphdr));
2252 if (m == NULL)
2253 goto fail;
2254 ip = mtodoff(m, struct ip *, hoff);
2255 }
2256
2257 th = (struct tcphdr *)((caddr_t)ip + iphlen);
2258 thoff = th->th_off << 2;
2259
2260 if (m->m_len < hoff + iphlen + thoff) {
2261 m = m_pullup(m, hoff + iphlen + thoff);
2262 if (m == NULL)
2263 goto fail;
2264 ip = mtodoff(m, struct ip *, hoff);
2265 th = (struct tcphdr *)((caddr_t)ip + iphlen);
2266 }
2267
2268 *mp = m;
2269 *ip0 = ip;
2270 *iphlen0 = iphlen;
2271 *th0 = th;
2272 *thoff0 = thoff;
2273 return TRUE;
2274
2275fail:
2276 if (m != NULL)
2277 m_freem(m);
2278 *mp = NULL;
2279 return FALSE;
2280}