2 * SPDX-License-Identifier: BSD-3-Clause
4 * Copyright (c) 1982, 1986, 1988, 1990, 1993, 1995
5 * The Regents of the University of California. All rights reserved.
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 * 3. Neither the name of the University nor the names of its contributors
16 * may be used to endorse or promote products derived from this software
17 * without specific prior written permission.
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * @(#)tcp_subr.c 8.2 (Berkeley) 5/24/95
34 #include <sys/cdefs.h>
35 __FBSDID("$FreeBSD$");
38 #include "opt_inet6.h"
39 #include "opt_ipsec.h"
40 #include "opt_tcpdebug.h"
42 #include <sys/param.h>
43 #include <sys/systm.h>
44 #include <sys/callout.h>
45 #include <sys/eventhandler.h>
47 #include <sys/hhook.h>
49 #include <sys/kernel.h>
51 #include <sys/khelp.h>
53 #include <sys/sysctl.h>
55 #include <sys/malloc.h>
56 #include <sys/refcount.h>
59 #include <sys/domain.h>
64 #include <sys/socket.h>
65 #include <sys/socketvar.h>
66 #include <sys/protosw.h>
67 #include <sys/random.h>
71 #include <net/route.h>
73 #include <net/if_var.h>
76 #include <netinet/in.h>
77 #include <netinet/in_fib.h>
78 #include <netinet/in_kdtrace.h>
79 #include <netinet/in_pcb.h>
80 #include <netinet/in_systm.h>
81 #include <netinet/in_var.h>
82 #include <netinet/ip.h>
83 #include <netinet/ip_icmp.h>
84 #include <netinet/ip_var.h>
86 #include <netinet/icmp6.h>
87 #include <netinet/ip6.h>
88 #include <netinet6/in6_fib.h>
89 #include <netinet6/in6_pcb.h>
90 #include <netinet6/ip6_var.h>
91 #include <netinet6/scope6_var.h>
92 #include <netinet6/nd6.h>
95 #include <netinet/tcp.h>
96 #include <netinet/tcp_fsm.h>
97 #include <netinet/tcp_seq.h>
98 #include <netinet/tcp_timer.h>
99 #include <netinet/tcp_var.h>
100 #include <netinet/tcp_log_buf.h>
101 #include <netinet/tcp_syncache.h>
102 #include <netinet/tcp_hpts.h>
103 #include <netinet/cc/cc.h>
105 #include <netinet6/tcp6_var.h>
107 #include <netinet/tcpip.h>
108 #include <netinet/tcp_fastopen.h>
110 #include <netinet/tcp_pcap.h>
113 #include <netinet/tcp_debug.h>
116 #include <netinet6/ip6protosw.h>
119 #include <netinet/tcp_offload.h>
122 #include <netipsec/ipsec_support.h>
124 #include <machine/in_cksum.h>
127 #include <security/mac/mac_framework.h>
129 VNET_DEFINE(int, tcp_mssdflt) = TCP_MSS;
131 VNET_DEFINE(int, tcp_v6mssdflt) = TCP6_MSS;
134 struct rwlock tcp_function_lock;
137 sysctl_net_inet_tcp_mss_check(SYSCTL_HANDLER_ARGS)
142 error = sysctl_handle_int(oidp, &new, 0, req);
143 if (error == 0 && req->newptr) {
144 if (new < TCP_MINMSS)
152 SYSCTL_PROC(_net_inet_tcp, TCPCTL_MSSDFLT, mssdflt,
153 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW, &VNET_NAME(tcp_mssdflt), 0,
154 &sysctl_net_inet_tcp_mss_check, "I",
155 "Default TCP Maximum Segment Size");
159 sysctl_net_inet_tcp_mss_v6_check(SYSCTL_HANDLER_ARGS)
163 new = V_tcp_v6mssdflt;
164 error = sysctl_handle_int(oidp, &new, 0, req);
165 if (error == 0 && req->newptr) {
166 if (new < TCP_MINMSS)
169 V_tcp_v6mssdflt = new;
174 SYSCTL_PROC(_net_inet_tcp, TCPCTL_V6MSSDFLT, v6mssdflt,
175 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW, &VNET_NAME(tcp_v6mssdflt), 0,
176 &sysctl_net_inet_tcp_mss_v6_check, "I",
177 "Default TCP Maximum Segment Size for IPv6");
181 * Minimum MSS we accept and use. This prevents DoS attacks where
182 * we are forced to a ridiculous low MSS like 20 and send hundreds
183 * of packets instead of one. The effect scales with the available
184 * bandwidth and quickly saturates the CPU and network interface
185 * with packet generation and sending. Set to zero to disable MINMSS
186 * checking. This setting prevents us from sending too small packets.
188 VNET_DEFINE(int, tcp_minmss) = TCP_MINMSS;
189 SYSCTL_INT(_net_inet_tcp, OID_AUTO, minmss, CTLFLAG_VNET | CTLFLAG_RW,
190 &VNET_NAME(tcp_minmss), 0,
191 "Minimum TCP Maximum Segment Size");
193 VNET_DEFINE(int, tcp_do_rfc1323) = 1;
194 SYSCTL_INT(_net_inet_tcp, TCPCTL_DO_RFC1323, rfc1323, CTLFLAG_VNET | CTLFLAG_RW,
195 &VNET_NAME(tcp_do_rfc1323), 0,
196 "Enable rfc1323 (high performance TCP) extensions");
198 static int tcp_log_debug = 0;
199 SYSCTL_INT(_net_inet_tcp, OID_AUTO, log_debug, CTLFLAG_RW,
200 &tcp_log_debug, 0, "Log errors caused by incoming TCP segments");
202 static int tcp_tcbhashsize;
203 SYSCTL_INT(_net_inet_tcp, OID_AUTO, tcbhashsize, CTLFLAG_RDTUN | CTLFLAG_NOFETCH,
204 &tcp_tcbhashsize, 0, "Size of TCP control-block hashtable");
206 static int do_tcpdrain = 1;
207 SYSCTL_INT(_net_inet_tcp, OID_AUTO, do_tcpdrain, CTLFLAG_RW, &do_tcpdrain, 0,
208 "Enable tcp_drain routine for extra help when low on mbufs");
210 SYSCTL_UINT(_net_inet_tcp, OID_AUTO, pcbcount, CTLFLAG_VNET | CTLFLAG_RD,
211 &VNET_NAME(tcbinfo.ipi_count), 0, "Number of active PCBs");
213 static VNET_DEFINE(int, icmp_may_rst) = 1;
214 #define V_icmp_may_rst VNET(icmp_may_rst)
215 SYSCTL_INT(_net_inet_tcp, OID_AUTO, icmp_may_rst, CTLFLAG_VNET | CTLFLAG_RW,
216 &VNET_NAME(icmp_may_rst), 0,
217 "Certain ICMP unreachable messages may abort connections in SYN_SENT");
219 static VNET_DEFINE(int, tcp_isn_reseed_interval) = 0;
220 #define V_tcp_isn_reseed_interval VNET(tcp_isn_reseed_interval)
221 SYSCTL_INT(_net_inet_tcp, OID_AUTO, isn_reseed_interval, CTLFLAG_VNET | CTLFLAG_RW,
222 &VNET_NAME(tcp_isn_reseed_interval), 0,
223 "Seconds between reseeding of ISN secret");
225 static int tcp_soreceive_stream;
226 SYSCTL_INT(_net_inet_tcp, OID_AUTO, soreceive_stream, CTLFLAG_RDTUN,
227 &tcp_soreceive_stream, 0, "Using soreceive_stream for TCP sockets");
229 VNET_DEFINE(uma_zone_t, sack_hole_zone);
230 #define V_sack_hole_zone VNET(sack_hole_zone)
233 VNET_DEFINE(struct hhook_head *, tcp_hhh[HHOOK_TCP_LAST+1]);
236 static int tcp_default_fb_init(struct tcpcb *tp);
237 static void tcp_default_fb_fini(struct tcpcb *tp, int tcb_is_purged);
238 static int tcp_default_handoff_ok(struct tcpcb *tp);
239 static struct inpcb *tcp_notify(struct inpcb *, int);
240 static struct inpcb *tcp_mtudisc_notify(struct inpcb *, int);
241 static void tcp_mtudisc(struct inpcb *, int);
242 static char * tcp_log_addr(struct in_conninfo *inc, struct tcphdr *th,
243 void *ip4hdr, const void *ip6hdr);
246 static struct tcp_function_block tcp_def_funcblk = {
247 .tfb_tcp_block_name = "freebsd",
248 .tfb_tcp_output = tcp_output,
249 .tfb_tcp_do_segment = tcp_do_segment,
250 .tfb_tcp_ctloutput = tcp_default_ctloutput,
251 .tfb_tcp_handoff_ok = tcp_default_handoff_ok,
252 .tfb_tcp_fb_init = tcp_default_fb_init,
253 .tfb_tcp_fb_fini = tcp_default_fb_fini,
256 int t_functions_inited = 0;
257 static int tcp_fb_cnt = 0;
258 struct tcp_funchead t_functions;
259 static struct tcp_function_block *tcp_func_set_ptr = &tcp_def_funcblk;
262 init_tcp_functions(void)
264 if (t_functions_inited == 0) {
265 TAILQ_INIT(&t_functions);
266 rw_init_flags(&tcp_function_lock, "tcp_func_lock" , 0);
267 t_functions_inited = 1;
271 static struct tcp_function_block *
272 find_tcp_functions_locked(struct tcp_function_set *fs)
274 struct tcp_function *f;
275 struct tcp_function_block *blk=NULL;
277 TAILQ_FOREACH(f, &t_functions, tf_next) {
278 if (strcmp(f->tf_name, fs->function_set_name) == 0) {
286 static struct tcp_function_block *
287 find_tcp_fb_locked(struct tcp_function_block *blk, struct tcp_function **s)
289 struct tcp_function_block *rblk=NULL;
290 struct tcp_function *f;
292 TAILQ_FOREACH(f, &t_functions, tf_next) {
293 if (f->tf_fb == blk) {
304 struct tcp_function_block *
305 find_and_ref_tcp_functions(struct tcp_function_set *fs)
307 struct tcp_function_block *blk;
309 rw_rlock(&tcp_function_lock);
310 blk = find_tcp_functions_locked(fs);
312 refcount_acquire(&blk->tfb_refcnt);
313 rw_runlock(&tcp_function_lock);
317 struct tcp_function_block *
318 find_and_ref_tcp_fb(struct tcp_function_block *blk)
320 struct tcp_function_block *rblk;
322 rw_rlock(&tcp_function_lock);
323 rblk = find_tcp_fb_locked(blk, NULL);
325 refcount_acquire(&rblk->tfb_refcnt);
326 rw_runlock(&tcp_function_lock);
330 static struct tcp_function_block *
331 find_and_ref_tcp_default_fb(void)
333 struct tcp_function_block *rblk;
335 rw_rlock(&tcp_function_lock);
336 rblk = tcp_func_set_ptr;
337 refcount_acquire(&rblk->tfb_refcnt);
338 rw_runlock(&tcp_function_lock);
343 tcp_switch_back_to_default(struct tcpcb *tp)
345 struct tcp_function_block *tfb;
347 KASSERT(tp->t_fb != &tcp_def_funcblk,
348 ("%s: called by the built-in default stack", __func__));
351 * Release the old stack. This function will either find a new one
354 if (tp->t_fb->tfb_tcp_fb_fini != NULL)
355 (*tp->t_fb->tfb_tcp_fb_fini)(tp, 0);
356 refcount_release(&tp->t_fb->tfb_refcnt);
359 * Now, we'll find a new function block to use.
360 * Start by trying the current user-selected
361 * default, unless this stack is the user-selected
364 tfb = find_and_ref_tcp_default_fb();
365 if (tfb == tp->t_fb) {
366 refcount_release(&tfb->tfb_refcnt);
369 /* Does the stack accept this connection? */
370 if (tfb != NULL && tfb->tfb_tcp_handoff_ok != NULL &&
371 (*tfb->tfb_tcp_handoff_ok)(tp)) {
372 refcount_release(&tfb->tfb_refcnt);
375 /* Try to use that stack. */
377 /* Initialize the new stack. If it succeeds, we are done. */
379 if (tp->t_fb->tfb_tcp_fb_init == NULL ||
380 (*tp->t_fb->tfb_tcp_fb_init)(tp) == 0)
384 * Initialization failed. Release the reference count on
387 refcount_release(&tfb->tfb_refcnt);
391 * If that wasn't feasible, use the built-in default
392 * stack which is not allowed to reject anyone.
394 tfb = find_and_ref_tcp_fb(&tcp_def_funcblk);
396 /* there always should be a default */
397 panic("Can't refer to tcp_def_funcblk");
399 if (tfb->tfb_tcp_handoff_ok != NULL) {
400 if ((*tfb->tfb_tcp_handoff_ok) (tp)) {
401 /* The default stack cannot say no */
402 panic("Default stack rejects a new session?");
406 if (tp->t_fb->tfb_tcp_fb_init != NULL &&
407 (*tp->t_fb->tfb_tcp_fb_init)(tp)) {
408 /* The default stack cannot fail */
409 panic("Default stack initialization failed");
414 sysctl_net_inet_default_tcp_functions(SYSCTL_HANDLER_ARGS)
417 struct tcp_function_set fs;
418 struct tcp_function_block *blk;
420 memset(&fs, 0, sizeof(fs));
421 rw_rlock(&tcp_function_lock);
422 blk = find_tcp_fb_locked(tcp_func_set_ptr, NULL);
425 strcpy(fs.function_set_name, blk->tfb_tcp_block_name);
426 fs.pcbcnt = blk->tfb_refcnt;
428 rw_runlock(&tcp_function_lock);
429 error = sysctl_handle_string(oidp, fs.function_set_name,
430 sizeof(fs.function_set_name), req);
432 /* Check for error or no change */
433 if (error != 0 || req->newptr == NULL)
436 rw_wlock(&tcp_function_lock);
437 blk = find_tcp_functions_locked(&fs);
439 (blk->tfb_flags & TCP_FUNC_BEING_REMOVED)) {
443 tcp_func_set_ptr = blk;
445 rw_wunlock(&tcp_function_lock);
449 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, functions_default,
450 CTLTYPE_STRING | CTLFLAG_RW,
451 NULL, 0, sysctl_net_inet_default_tcp_functions, "A",
452 "Set/get the default TCP functions");
455 sysctl_net_inet_list_available(SYSCTL_HANDLER_ARGS)
457 int error, cnt, linesz;
458 struct tcp_function *f;
464 rw_rlock(&tcp_function_lock);
465 TAILQ_FOREACH(f, &t_functions, tf_next) {
468 rw_runlock(&tcp_function_lock);
470 bufsz = (cnt+2) * ((TCP_FUNCTION_NAME_LEN_MAX * 2) + 13) + 1;
471 buffer = malloc(bufsz, M_TEMP, M_WAITOK);
476 linesz = snprintf(cp, bufsz, "\n%-32s%c %-32s %s\n", "Stack", 'D',
477 "Alias", "PCB count");
482 rw_rlock(&tcp_function_lock);
483 TAILQ_FOREACH(f, &t_functions, tf_next) {
484 alias = (f->tf_name != f->tf_fb->tfb_tcp_block_name);
485 linesz = snprintf(cp, bufsz, "%-32s%c %-32s %u\n",
486 f->tf_fb->tfb_tcp_block_name,
487 (f->tf_fb == tcp_func_set_ptr) ? '*' : ' ',
488 alias ? f->tf_name : "-",
489 f->tf_fb->tfb_refcnt);
490 if (linesz >= bufsz) {
498 rw_runlock(&tcp_function_lock);
500 error = sysctl_handle_string(oidp, buffer, outsz + 1, req);
501 free(buffer, M_TEMP);
505 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, functions_available,
506 CTLTYPE_STRING|CTLFLAG_RD,
507 NULL, 0, sysctl_net_inet_list_available, "A",
508 "list available TCP Function sets");
511 * Exports one (struct tcp_function_info) for each alias/name.
514 sysctl_net_inet_list_func_info(SYSCTL_HANDLER_ARGS)
517 struct tcp_function *f;
518 struct tcp_function_info tfi;
521 * We don't allow writes.
523 if (req->newptr != NULL)
527 * Wire the old buffer so we can directly copy the functions to
528 * user space without dropping the lock.
530 if (req->oldptr != NULL) {
531 error = sysctl_wire_old_buffer(req, 0);
537 * Walk the list and copy out matching entries. If INVARIANTS
538 * is compiled in, also walk the list to verify the length of
539 * the list matches what we have recorded.
541 rw_rlock(&tcp_function_lock);
545 if (req->oldptr == NULL) {
550 TAILQ_FOREACH(f, &t_functions, tf_next) {
554 if (req->oldptr != NULL) {
555 tfi.tfi_refcnt = f->tf_fb->tfb_refcnt;
556 tfi.tfi_id = f->tf_fb->tfb_id;
557 (void)strncpy(tfi.tfi_alias, f->tf_name,
558 TCP_FUNCTION_NAME_LEN_MAX);
559 tfi.tfi_alias[TCP_FUNCTION_NAME_LEN_MAX - 1] = '\0';
560 (void)strncpy(tfi.tfi_name,
561 f->tf_fb->tfb_tcp_block_name,
562 TCP_FUNCTION_NAME_LEN_MAX);
563 tfi.tfi_name[TCP_FUNCTION_NAME_LEN_MAX - 1] = '\0';
564 error = SYSCTL_OUT(req, &tfi, sizeof(tfi));
566 * Don't stop on error, as that is the
567 * mechanism we use to accumulate length
568 * information if the buffer was too short.
572 KASSERT(cnt == tcp_fb_cnt,
573 ("%s: cnt (%d) != tcp_fb_cnt (%d)", __func__, cnt, tcp_fb_cnt));
577 rw_runlock(&tcp_function_lock);
578 if (req->oldptr == NULL)
579 error = SYSCTL_OUT(req, NULL,
580 (cnt + 1) * sizeof(struct tcp_function_info));
585 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, function_info,
586 CTLTYPE_OPAQUE | CTLFLAG_SKIP | CTLFLAG_RD | CTLFLAG_MPSAFE,
587 NULL, 0, sysctl_net_inet_list_func_info, "S,tcp_function_info",
588 "List TCP function block name-to-ID mappings");
591 * tfb_tcp_handoff_ok() function for the default stack.
592 * Note that we'll basically try to take all comers.
595 tcp_default_handoff_ok(struct tcpcb *tp)
602 * tfb_tcp_fb_init() function for the default stack.
604 * This handles making sure we have appropriate timers set if you are
605 * transitioning a socket that has some amount of setup done.
607 * The init() fuction from the default can *never* return non-zero i.e.
608 * it is required to always succeed since it is the stack of last resort!
611 tcp_default_fb_init(struct tcpcb *tp)
616 INP_WLOCK_ASSERT(tp->t_inpcb);
618 KASSERT(tp->t_state >= 0 && tp->t_state < TCPS_TIME_WAIT,
619 ("%s: connection %p in unexpected state %d", __func__, tp,
623 * Nothing to do for ESTABLISHED or LISTEN states. And, we don't
624 * know what to do for unexpected states (which includes TIME_WAIT).
626 if (tp->t_state <= TCPS_LISTEN || tp->t_state >= TCPS_TIME_WAIT)
630 * Make sure some kind of transmission timer is set if there is
633 so = tp->t_inpcb->inp_socket;
634 if ((!TCPS_HAVEESTABLISHED(tp->t_state) || sbavail(&so->so_snd) ||
635 tp->snd_una != tp->snd_max) && !(tcp_timer_active(tp, TT_REXMT) ||
636 tcp_timer_active(tp, TT_PERSIST))) {
638 * If the session has established and it looks like it should
639 * be in the persist state, set the persist timer. Otherwise,
640 * set the retransmit timer.
642 if (TCPS_HAVEESTABLISHED(tp->t_state) && tp->snd_wnd == 0 &&
643 (int32_t)(tp->snd_nxt - tp->snd_una) <
644 (int32_t)sbavail(&so->so_snd))
647 tcp_timer_activate(tp, TT_REXMT, tp->t_rxtcur);
650 /* All non-embryonic sessions get a keepalive timer. */
651 if (!tcp_timer_active(tp, TT_KEEP))
652 tcp_timer_activate(tp, TT_KEEP,
653 TCPS_HAVEESTABLISHED(tp->t_state) ? TP_KEEPIDLE(tp) :
660 * tfb_tcp_fb_fini() function for the default stack.
662 * This changes state as necessary (or prudent) to prepare for another stack
663 * to assume responsibility for the connection.
666 tcp_default_fb_fini(struct tcpcb *tp, int tcb_is_purged)
669 INP_WLOCK_ASSERT(tp->t_inpcb);
674 * Target size of TCP PCB hash tables. Must be a power of two.
676 * Note that this can be overridden by the kernel environment
677 * variable net.inet.tcp.tcbhashsize
680 #define TCBHASHSIZE 0
685 * Callouts should be moved into struct tcp directly. They are currently
686 * separate because the tcpcb structure is exported to userland for sysctl
687 * parsing purposes, which do not know about callouts.
698 static VNET_DEFINE(uma_zone_t, tcpcb_zone);
699 #define V_tcpcb_zone VNET(tcpcb_zone)
701 MALLOC_DEFINE(M_TCPLOG, "tcplog", "TCP address and flags print buffers");
702 MALLOC_DEFINE(M_TCPFUNCTIONS, "tcpfunc", "TCP function set memory");
704 static struct mtx isn_mtx;
706 #define ISN_LOCK_INIT() mtx_init(&isn_mtx, "isn_mtx", NULL, MTX_DEF)
707 #define ISN_LOCK() mtx_lock(&isn_mtx)
708 #define ISN_UNLOCK() mtx_unlock(&isn_mtx)
711 * TCP initialization.
714 tcp_zone_change(void *tag)
717 uma_zone_set_max(V_tcbinfo.ipi_zone, maxsockets);
718 uma_zone_set_max(V_tcpcb_zone, maxsockets);
719 tcp_tw_zone_change();
723 tcp_inpcb_init(void *mem, int size, int flags)
725 struct inpcb *inp = mem;
727 INP_LOCK_INIT(inp, "inp", "tcpinp");
732 * Take a value and get the next power of 2 that doesn't overflow.
733 * Used to size the tcp_inpcb hash buckets.
736 maketcp_hashsize(int size)
742 * get the next power of 2 higher than maxsockets.
744 hashsize = 1 << fls(size);
745 /* catch overflow, and just go one power of 2 smaller */
746 if (hashsize < size) {
747 hashsize = 1 << (fls(size) - 1);
752 static volatile int next_tcp_stack_id = 1;
755 * Register a TCP function block with the name provided in the names
756 * array. (Note that this function does NOT automatically register
757 * blk->tfb_tcp_block_name as a stack name. Therefore, you should
758 * explicitly include blk->tfb_tcp_block_name in the list of names if
759 * you wish to register the stack with that name.)
761 * Either all name registrations will succeed or all will fail. If
762 * a name registration fails, the function will update the num_names
763 * argument to point to the array index of the name that encountered
766 * Returns 0 on success, or an error code on failure.
769 register_tcp_functions_as_names(struct tcp_function_block *blk, int wait,
770 const char *names[], int *num_names)
772 struct tcp_function *n;
773 struct tcp_function_set fs;
776 KASSERT(names != NULL && *num_names > 0,
777 ("%s: Called with 0-length name list", __func__));
778 KASSERT(names != NULL, ("%s: Called with NULL name list", __func__));
780 if (t_functions_inited == 0) {
781 init_tcp_functions();
783 if ((blk->tfb_tcp_output == NULL) ||
784 (blk->tfb_tcp_do_segment == NULL) ||
785 (blk->tfb_tcp_ctloutput == NULL) ||
786 (strlen(blk->tfb_tcp_block_name) == 0)) {
788 * These functions are required and you
794 if (blk->tfb_tcp_timer_stop_all ||
795 blk->tfb_tcp_timer_activate ||
796 blk->tfb_tcp_timer_active ||
797 blk->tfb_tcp_timer_stop) {
799 * If you define one timer function you
800 * must have them all.
802 if ((blk->tfb_tcp_timer_stop_all == NULL) ||
803 (blk->tfb_tcp_timer_activate == NULL) ||
804 (blk->tfb_tcp_timer_active == NULL) ||
805 (blk->tfb_tcp_timer_stop == NULL)) {
811 refcount_init(&blk->tfb_refcnt, 0);
813 blk->tfb_id = atomic_fetchadd_int(&next_tcp_stack_id, 1);
814 for (i = 0; i < *num_names; i++) {
815 n = malloc(sizeof(struct tcp_function), M_TCPFUNCTIONS, wait);
822 (void)strncpy(fs.function_set_name, names[i],
823 TCP_FUNCTION_NAME_LEN_MAX);
824 fs.function_set_name[TCP_FUNCTION_NAME_LEN_MAX - 1] = '\0';
825 rw_wlock(&tcp_function_lock);
826 if (find_tcp_functions_locked(&fs) != NULL) {
827 /* Duplicate name space not allowed */
828 rw_wunlock(&tcp_function_lock);
829 free(n, M_TCPFUNCTIONS);
833 (void)strncpy(n->tf_name, names[i], TCP_FUNCTION_NAME_LEN_MAX);
834 n->tf_name[TCP_FUNCTION_NAME_LEN_MAX - 1] = '\0';
835 TAILQ_INSERT_TAIL(&t_functions, n, tf_next);
837 rw_wunlock(&tcp_function_lock);
843 * Deregister the names we just added. Because registration failed
844 * for names[i], we don't need to deregister that name.
847 rw_wlock(&tcp_function_lock);
849 TAILQ_FOREACH(n, &t_functions, tf_next) {
850 if (!strncmp(n->tf_name, names[i],
851 TCP_FUNCTION_NAME_LEN_MAX)) {
852 TAILQ_REMOVE(&t_functions, n, tf_next);
855 free(n, M_TCPFUNCTIONS);
860 rw_wunlock(&tcp_function_lock);
865 * Register a TCP function block using the name provided in the name
868 * Returns 0 on success, or an error code on failure.
871 register_tcp_functions_as_name(struct tcp_function_block *blk, const char *name,
874 const char *name_list[1];
881 name_list[0] = blk->tfb_tcp_block_name;
882 rv = register_tcp_functions_as_names(blk, wait, name_list, &num_names);
887 * Register a TCP function block using the name defined in
888 * blk->tfb_tcp_block_name.
890 * Returns 0 on success, or an error code on failure.
893 register_tcp_functions(struct tcp_function_block *blk, int wait)
896 return (register_tcp_functions_as_name(blk, NULL, wait));
900 * Deregister all names associated with a function block. This
901 * functionally removes the function block from use within the system.
903 * When called with a true quiesce argument, mark the function block
904 * as being removed so no more stacks will use it and determine
905 * whether the removal would succeed.
907 * When called with a false quiesce argument, actually attempt the
910 * When called with a force argument, attempt to switch all TCBs to
911 * use the default stack instead of returning EBUSY.
913 * Returns 0 on success (or if the removal would succeed, or an error
917 deregister_tcp_functions(struct tcp_function_block *blk, bool quiesce,
920 struct tcp_function *f;
922 if (strcmp(blk->tfb_tcp_block_name, "default") == 0) {
923 /* You can't un-register the default */
926 rw_wlock(&tcp_function_lock);
927 if (blk == tcp_func_set_ptr) {
928 /* You can't free the current default */
929 rw_wunlock(&tcp_function_lock);
932 /* Mark the block so no more stacks can use it. */
933 blk->tfb_flags |= TCP_FUNC_BEING_REMOVED;
935 * If TCBs are still attached to the stack, attempt to switch them
936 * to the default stack.
938 if (force && blk->tfb_refcnt) {
941 VNET_ITERATOR_DECL(vnet_iter);
943 rw_wunlock(&tcp_function_lock);
947 VNET_FOREACH(vnet_iter) {
948 CURVNET_SET(vnet_iter);
949 INP_INFO_WLOCK(&V_tcbinfo);
950 CK_LIST_FOREACH(inp, V_tcbinfo.ipi_listhead, inp_list) {
952 if (inp->inp_flags & INP_TIMEWAIT) {
957 if (tp == NULL || tp->t_fb != blk) {
961 tcp_switch_back_to_default(tp);
964 INP_INFO_WUNLOCK(&V_tcbinfo);
969 rw_wlock(&tcp_function_lock);
971 if (blk->tfb_refcnt) {
972 /* TCBs still attached. */
973 rw_wunlock(&tcp_function_lock);
978 rw_wunlock(&tcp_function_lock);
981 /* Remove any function names that map to this function block. */
982 while (find_tcp_fb_locked(blk, &f) != NULL) {
983 TAILQ_REMOVE(&t_functions, f, tf_next);
986 free(f, M_TCPFUNCTIONS);
988 rw_wunlock(&tcp_function_lock);
995 const char *tcbhash_tuneable;
998 tcbhash_tuneable = "net.inet.tcp.tcbhashsize";
1001 if (hhook_head_register(HHOOK_TYPE_TCP, HHOOK_TCP_EST_IN,
1002 &V_tcp_hhh[HHOOK_TCP_EST_IN], HHOOK_NOWAIT|HHOOK_HEADISINVNET) != 0)
1003 printf("%s: WARNING: unable to register helper hook\n", __func__);
1004 if (hhook_head_register(HHOOK_TYPE_TCP, HHOOK_TCP_EST_OUT,
1005 &V_tcp_hhh[HHOOK_TCP_EST_OUT], HHOOK_NOWAIT|HHOOK_HEADISINVNET) != 0)
1006 printf("%s: WARNING: unable to register helper hook\n", __func__);
1008 hashsize = TCBHASHSIZE;
1009 TUNABLE_INT_FETCH(tcbhash_tuneable, &hashsize);
1010 if (hashsize == 0) {
1012 * Auto tune the hash size based on maxsockets.
1013 * A perfect hash would have a 1:1 mapping
1014 * (hashsize = maxsockets) however it's been
1015 * suggested that O(2) average is better.
1017 hashsize = maketcp_hashsize(maxsockets / 4);
1019 * Our historical default is 512,
1020 * do not autotune lower than this.
1024 if (bootverbose && IS_DEFAULT_VNET(curvnet))
1025 printf("%s: %s auto tuned to %d\n", __func__,
1026 tcbhash_tuneable, hashsize);
1029 * We require a hashsize to be a power of two.
1030 * Previously if it was not a power of two we would just reset it
1031 * back to 512, which could be a nasty surprise if you did not notice
1032 * the error message.
1033 * Instead what we do is clip it to the closest power of two lower
1034 * than the specified hash value.
1036 if (!powerof2(hashsize)) {
1037 int oldhashsize = hashsize;
1039 hashsize = maketcp_hashsize(hashsize);
1040 /* prevent absurdly low value */
1043 printf("%s: WARNING: TCB hash size not a power of 2, "
1044 "clipped from %d to %d.\n", __func__, oldhashsize,
1047 in_pcbinfo_init(&V_tcbinfo, "tcp", &V_tcb, hashsize, hashsize,
1048 "tcp_inpcb", tcp_inpcb_init, IPI_HASHFIELDS_4TUPLE);
1051 * These have to be type stable for the benefit of the timers.
1053 V_tcpcb_zone = uma_zcreate("tcpcb", sizeof(struct tcpcb_mem),
1054 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
1055 uma_zone_set_max(V_tcpcb_zone, maxsockets);
1056 uma_zone_set_warning(V_tcpcb_zone, "kern.ipc.maxsockets limit reached");
1062 TUNABLE_INT_FETCH("net.inet.tcp.sack.enable", &V_tcp_do_sack);
1063 V_sack_hole_zone = uma_zcreate("sackhole", sizeof(struct sackhole),
1064 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
1066 tcp_fastopen_init();
1068 /* Skip initialization of globals for non-default instances. */
1069 if (!IS_DEFAULT_VNET(curvnet))
1072 tcp_reass_global_init();
1074 /* XXX virtualize those bellow? */
1075 tcp_delacktime = TCPTV_DELACK;
1076 tcp_keepinit = TCPTV_KEEP_INIT;
1077 tcp_keepidle = TCPTV_KEEP_IDLE;
1078 tcp_keepintvl = TCPTV_KEEPINTVL;
1079 tcp_maxpersistidle = TCPTV_KEEP_IDLE;
1080 tcp_msl = TCPTV_MSL;
1081 tcp_rexmit_min = TCPTV_MIN;
1082 if (tcp_rexmit_min < 1)
1084 tcp_persmin = TCPTV_PERSMIN;
1085 tcp_persmax = TCPTV_PERSMAX;
1086 tcp_rexmit_slop = TCPTV_CPU_VAR;
1087 tcp_finwait2_timeout = TCPTV_FINWAIT2_TIMEOUT;
1088 tcp_tcbhashsize = hashsize;
1089 /* Setup the tcp function block list */
1090 init_tcp_functions();
1091 register_tcp_functions(&tcp_def_funcblk, M_WAITOK);
1093 /* Initialize the TCP logging data. */
1097 if (tcp_soreceive_stream) {
1099 tcp_usrreqs.pru_soreceive = soreceive_stream;
1102 tcp6_usrreqs.pru_soreceive = soreceive_stream;
1107 #define TCP_MINPROTOHDR (sizeof(struct ip6_hdr) + sizeof(struct tcphdr))
1109 #define TCP_MINPROTOHDR (sizeof(struct tcpiphdr))
1111 if (max_protohdr < TCP_MINPROTOHDR)
1112 max_protohdr = TCP_MINPROTOHDR;
1113 if (max_linkhdr + TCP_MINPROTOHDR > MHLEN)
1115 #undef TCP_MINPROTOHDR
1118 EVENTHANDLER_REGISTER(shutdown_pre_sync, tcp_fini, NULL,
1119 SHUTDOWN_PRI_DEFAULT);
1120 EVENTHANDLER_REGISTER(maxsockets_change, tcp_zone_change, NULL,
1121 EVENTHANDLER_PRI_ANY);
1129 tcp_destroy(void *unused __unused)
1137 * All our processes are gone, all our sockets should be cleaned
1138 * up, which means, we should be past the tcp_discardcb() calls.
1139 * Sleep to let all tcpcb timers really disappear and cleanup.
1142 INP_LIST_RLOCK(&V_tcbinfo);
1143 n = V_tcbinfo.ipi_count;
1144 INP_LIST_RUNLOCK(&V_tcbinfo);
1147 pause("tcpdes", hz / 10);
1152 in_pcbinfo_destroy(&V_tcbinfo);
1153 /* tcp_discardcb() clears the sack_holes up. */
1154 uma_zdestroy(V_sack_hole_zone);
1155 uma_zdestroy(V_tcpcb_zone);
1158 * Cannot free the zone until all tcpcbs are released as we attach
1159 * the allocations to them.
1161 tcp_fastopen_destroy();
1164 error = hhook_head_deregister(V_tcp_hhh[HHOOK_TCP_EST_IN]);
1166 printf("%s: WARNING: unable to deregister helper hook "
1167 "type=%d, id=%d: error %d returned\n", __func__,
1168 HHOOK_TYPE_TCP, HHOOK_TCP_EST_IN, error);
1170 error = hhook_head_deregister(V_tcp_hhh[HHOOK_TCP_EST_OUT]);
1172 printf("%s: WARNING: unable to deregister helper hook "
1173 "type=%d, id=%d: error %d returned\n", __func__,
1174 HHOOK_TYPE_TCP, HHOOK_TCP_EST_OUT, error);
1178 VNET_SYSUNINIT(tcp, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH, tcp_destroy, NULL);
1188 * Fill in the IP and TCP headers for an outgoing packet, given the tcpcb.
1189 * tcp_template used to store this data in mbufs, but we now recopy it out
1190 * of the tcpcb each time to conserve mbufs.
1193 tcpip_fillheaders(struct inpcb *inp, void *ip_ptr, void *tcp_ptr)
1195 struct tcphdr *th = (struct tcphdr *)tcp_ptr;
1197 INP_WLOCK_ASSERT(inp);
1200 if ((inp->inp_vflag & INP_IPV6) != 0) {
1201 struct ip6_hdr *ip6;
1203 ip6 = (struct ip6_hdr *)ip_ptr;
1204 ip6->ip6_flow = (ip6->ip6_flow & ~IPV6_FLOWINFO_MASK) |
1205 (inp->inp_flow & IPV6_FLOWINFO_MASK);
1206 ip6->ip6_vfc = (ip6->ip6_vfc & ~IPV6_VERSION_MASK) |
1207 (IPV6_VERSION & IPV6_VERSION_MASK);
1208 ip6->ip6_nxt = IPPROTO_TCP;
1209 ip6->ip6_plen = htons(sizeof(struct tcphdr));
1210 ip6->ip6_src = inp->in6p_laddr;
1211 ip6->ip6_dst = inp->in6p_faddr;
1214 #if defined(INET6) && defined(INET)
1221 ip = (struct ip *)ip_ptr;
1222 ip->ip_v = IPVERSION;
1224 ip->ip_tos = inp->inp_ip_tos;
1228 ip->ip_ttl = inp->inp_ip_ttl;
1230 ip->ip_p = IPPROTO_TCP;
1231 ip->ip_src = inp->inp_laddr;
1232 ip->ip_dst = inp->inp_faddr;
1235 th->th_sport = inp->inp_lport;
1236 th->th_dport = inp->inp_fport;
1244 th->th_sum = 0; /* in_pseudo() is called later for ipv4 */
1248 * Create template to be used to send tcp packets on a connection.
1249 * Allocates an mbuf and fills in a skeletal tcp/ip header. The only
1250 * use for this function is in keepalives, which use tcp_respond.
1253 tcpip_maketemplate(struct inpcb *inp)
1257 t = malloc(sizeof(*t), M_TEMP, M_NOWAIT);
1260 tcpip_fillheaders(inp, (void *)&t->tt_ipgen, (void *)&t->tt_t);
1265 * Send a single message to the TCP at address specified by
1266 * the given TCP/IP header. If m == NULL, then we make a copy
1267 * of the tcpiphdr at th and send directly to the addressed host.
1268 * This is used to force keep alive messages out using the TCP
1269 * template for a connection. If flags are given then we send
1270 * a message back to the TCP which originated the segment th,
1271 * and discard the mbuf containing it and any other attached mbufs.
1273 * In any case the ack and sequence number of the transmitted
1274 * segment are as specified by the parameters.
1276 * NOTE: If m != NULL, then th must point to *inside* the mbuf.
1279 tcp_respond(struct tcpcb *tp, void *ipgen, struct tcphdr *th, struct mbuf *m,
1280 tcp_seq ack, tcp_seq seq, int flags)
1289 struct ip6_hdr *ip6;
1292 int optlen, tlen, win;
1295 KASSERT(tp != NULL || m != NULL, ("tcp_respond: tp and m both NULL"));
1298 isipv6 = ((struct ip *)ipgen)->ip_v == (IPV6_VERSION >> 4);
1305 KASSERT(inp != NULL, ("tcp control block w/o inpcb"));
1306 INP_WLOCK_ASSERT(inp);
1313 if (!(flags & TH_RST)) {
1314 win = sbspace(&inp->inp_socket->so_rcv);
1315 if (win > TCP_MAXWIN << tp->rcv_scale)
1316 win = TCP_MAXWIN << tp->rcv_scale;
1318 if ((tp->t_flags & TF_NOOPT) == 0)
1322 m = m_gethdr(M_NOWAIT, MT_DATA);
1325 m->m_data += max_linkhdr;
1328 bcopy((caddr_t)ip6, mtod(m, caddr_t),
1329 sizeof(struct ip6_hdr));
1330 ip6 = mtod(m, struct ip6_hdr *);
1331 nth = (struct tcphdr *)(ip6 + 1);
1335 bcopy((caddr_t)ip, mtod(m, caddr_t), sizeof(struct ip));
1336 ip = mtod(m, struct ip *);
1337 nth = (struct tcphdr *)(ip + 1);
1339 bcopy((caddr_t)th, (caddr_t)nth, sizeof(struct tcphdr));
1341 } else if (!M_WRITABLE(m)) {
1344 /* Can't reuse 'm', allocate a new mbuf. */
1345 n = m_gethdr(M_NOWAIT, MT_DATA);
1351 if (!m_dup_pkthdr(n, m, M_NOWAIT)) {
1357 n->m_data += max_linkhdr;
1358 /* m_len is set later */
1359 #define xchg(a,b,type) { type t; t=a; a=b; b=t; }
1362 bcopy((caddr_t)ip6, mtod(n, caddr_t),
1363 sizeof(struct ip6_hdr));
1364 ip6 = mtod(n, struct ip6_hdr *);
1365 xchg(ip6->ip6_dst, ip6->ip6_src, struct in6_addr);
1366 nth = (struct tcphdr *)(ip6 + 1);
1370 bcopy((caddr_t)ip, mtod(n, caddr_t), sizeof(struct ip));
1371 ip = mtod(n, struct ip *);
1372 xchg(ip->ip_dst.s_addr, ip->ip_src.s_addr, uint32_t);
1373 nth = (struct tcphdr *)(ip + 1);
1375 bcopy((caddr_t)th, (caddr_t)nth, sizeof(struct tcphdr));
1376 xchg(nth->th_dport, nth->th_sport, uint16_t);
1383 * XXX MRT We inherit the FIB, which is lucky.
1387 m->m_data = (caddr_t)ipgen;
1388 /* m_len is set later */
1391 xchg(ip6->ip6_dst, ip6->ip6_src, struct in6_addr);
1392 nth = (struct tcphdr *)(ip6 + 1);
1396 xchg(ip->ip_dst.s_addr, ip->ip_src.s_addr, uint32_t);
1397 nth = (struct tcphdr *)(ip + 1);
1401 * this is usually a case when an extension header
1402 * exists between the IPv6 header and the
1405 nth->th_sport = th->th_sport;
1406 nth->th_dport = th->th_dport;
1408 xchg(nth->th_dport, nth->th_sport, uint16_t);
1414 tlen = sizeof (struct ip6_hdr) + sizeof (struct tcphdr);
1416 #if defined(INET) && defined(INET6)
1420 tlen = sizeof (struct tcpiphdr);
1424 KASSERT(M_TRAILINGSPACE(m) >= tlen,
1425 ("Not enough trailing space for message (m=%p, need=%d, have=%ld)",
1426 m, tlen, (long)M_TRAILINGSPACE(m)));
1431 /* Make sure we have room. */
1432 if (M_TRAILINGSPACE(m) < TCP_MAXOLEN) {
1433 m->m_next = m_get(M_NOWAIT, MT_DATA);
1435 optp = mtod(m->m_next, u_char *);
1440 optp = (u_char *) (nth + 1);
1446 if (tp->t_flags & TF_RCVD_TSTMP) {
1447 to.to_tsval = tcp_ts_getticks() + tp->ts_offset;
1448 to.to_tsecr = tp->ts_recent;
1449 to.to_flags |= TOF_TS;
1451 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE)
1452 /* TCP-MD5 (RFC2385). */
1453 if (tp->t_flags & TF_SIGNATURE)
1454 to.to_flags |= TOF_SIGNATURE;
1456 /* Add the options. */
1457 tlen += optlen = tcp_addoptions(&to, optp);
1459 /* Update m_len in the correct mbuf. */
1460 optm->m_len += optlen;
1466 ip6->ip6_vfc = IPV6_VERSION;
1467 ip6->ip6_nxt = IPPROTO_TCP;
1468 ip6->ip6_plen = htons(tlen - sizeof(*ip6));
1471 #if defined(INET) && defined(INET6)
1476 ip->ip_len = htons(tlen);
1477 ip->ip_ttl = V_ip_defttl;
1478 if (V_path_mtu_discovery)
1479 ip->ip_off |= htons(IP_DF);
1482 m->m_pkthdr.len = tlen;
1483 m->m_pkthdr.rcvif = NULL;
1487 * Packet is associated with a socket, so allow the
1488 * label of the response to reflect the socket label.
1490 INP_WLOCK_ASSERT(inp);
1491 mac_inpcb_create_mbuf(inp, m);
1494 * Packet is not associated with a socket, so possibly
1495 * update the label in place.
1497 mac_netinet_tcp_reply(m);
1500 nth->th_seq = htonl(seq);
1501 nth->th_ack = htonl(ack);
1503 nth->th_off = (sizeof (struct tcphdr) + optlen) >> 2;
1504 nth->th_flags = flags;
1506 nth->th_win = htons((u_short) (win >> tp->rcv_scale));
1508 nth->th_win = htons((u_short)win);
1511 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE)
1512 if (to.to_flags & TOF_SIGNATURE) {
1513 if (!TCPMD5_ENABLED() ||
1514 TCPMD5_OUTPUT(m, nth, to.to_signature) != 0) {
1521 m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum);
1524 m->m_pkthdr.csum_flags = CSUM_TCP_IPV6;
1525 nth->th_sum = in6_cksum_pseudo(ip6,
1526 tlen - sizeof(struct ip6_hdr), IPPROTO_TCP, 0);
1527 ip6->ip6_hlim = in6_selecthlim(tp != NULL ? tp->t_inpcb :
1531 #if defined(INET6) && defined(INET)
1536 m->m_pkthdr.csum_flags = CSUM_TCP;
1537 nth->th_sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr,
1538 htons((u_short)(tlen - sizeof(struct ip) + ip->ip_p)));
1542 if (tp == NULL || (inp->inp_socket->so_options & SO_DEBUG))
1543 tcp_trace(TA_OUTPUT, 0, tp, mtod(m, void *), th, 0);
1545 TCP_PROBE3(debug__output, tp, th, m);
1547 TCP_PROBE5(accept__refused, NULL, NULL, m, tp, nth);
1551 TCP_PROBE5(send, NULL, tp, ip6, tp, nth);
1552 (void)ip6_output(m, NULL, NULL, 0, NULL, NULL, inp);
1555 #if defined(INET) && defined(INET6)
1560 TCP_PROBE5(send, NULL, tp, ip, tp, nth);
1561 (void)ip_output(m, NULL, NULL, 0, NULL, inp);
1567 * Create a new TCP control block, making an
1568 * empty reassembly queue and hooking it to the argument
1569 * protocol control block. The `inp' parameter must have
1570 * come from the zone allocator set up in tcp_init().
1573 tcp_newtcpcb(struct inpcb *inp)
1575 struct tcpcb_mem *tm;
1578 int isipv6 = (inp->inp_vflag & INP_IPV6) != 0;
1581 tm = uma_zalloc(V_tcpcb_zone, M_NOWAIT | M_ZERO);
1586 /* Initialise cc_var struct for this tcpcb. */
1588 tp->ccv->type = IPPROTO_TCP;
1589 tp->ccv->ccvc.tcp = tp;
1590 rw_rlock(&tcp_function_lock);
1591 tp->t_fb = tcp_func_set_ptr;
1592 refcount_acquire(&tp->t_fb->tfb_refcnt);
1593 rw_runlock(&tcp_function_lock);
1595 * Use the current system default CC algorithm.
1598 KASSERT(!STAILQ_EMPTY(&cc_list), ("cc_list is empty!"));
1599 CC_ALGO(tp) = CC_DEFAULT();
1602 if (CC_ALGO(tp)->cb_init != NULL)
1603 if (CC_ALGO(tp)->cb_init(tp->ccv) > 0) {
1604 if (tp->t_fb->tfb_tcp_fb_fini)
1605 (*tp->t_fb->tfb_tcp_fb_fini)(tp, 1);
1606 refcount_release(&tp->t_fb->tfb_refcnt);
1607 uma_zfree(V_tcpcb_zone, tm);
1613 if (khelp_init_osd(HELPER_CLASS_TCP, tp->osd)) {
1614 if (tp->t_fb->tfb_tcp_fb_fini)
1615 (*tp->t_fb->tfb_tcp_fb_fini)(tp, 1);
1616 refcount_release(&tp->t_fb->tfb_refcnt);
1617 uma_zfree(V_tcpcb_zone, tm);
1623 tp->t_vnet = inp->inp_vnet;
1625 tp->t_timers = &tm->tt;
1626 /* LIST_INIT(&tp->t_segq); */ /* XXX covered by M_ZERO */
1629 isipv6 ? V_tcp_v6mssdflt :
1633 /* Set up our timeouts. */
1634 callout_init(&tp->t_timers->tt_rexmt, 1);
1635 callout_init(&tp->t_timers->tt_persist, 1);
1636 callout_init(&tp->t_timers->tt_keep, 1);
1637 callout_init(&tp->t_timers->tt_2msl, 1);
1638 callout_init(&tp->t_timers->tt_delack, 1);
1640 if (V_tcp_do_rfc1323)
1641 tp->t_flags = (TF_REQ_SCALE|TF_REQ_TSTMP);
1643 tp->t_flags |= TF_SACK_PERMIT;
1644 TAILQ_INIT(&tp->snd_holes);
1646 * The tcpcb will hold a reference on its inpcb until tcp_discardcb()
1649 in_pcbref(inp); /* Reference for tcpcb */
1653 * Init srtt to TCPTV_SRTTBASE (0), so we can tell that we have no
1654 * rtt estimate. Set rttvar so that srtt + 4 * rttvar gives
1655 * reasonable initial retransmit time.
1657 tp->t_srtt = TCPTV_SRTTBASE;
1658 tp->t_rttvar = ((TCPTV_RTOBASE - TCPTV_SRTTBASE) << TCP_RTTVAR_SHIFT) / 4;
1659 tp->t_rttmin = tcp_rexmit_min;
1660 tp->t_rxtcur = TCPTV_RTOBASE;
1661 tp->snd_cwnd = TCP_MAXWIN << TCP_MAX_WINSHIFT;
1662 tp->snd_ssthresh = TCP_MAXWIN << TCP_MAX_WINSHIFT;
1663 tp->t_rcvtime = ticks;
1665 * IPv4 TTL initialization is necessary for an IPv6 socket as well,
1666 * because the socket may be bound to an IPv6 wildcard address,
1667 * which may match an IPv4-mapped IPv6 address.
1669 inp->inp_ip_ttl = V_ip_defttl;
1673 * Init the TCP PCAP queues.
1675 tcp_pcap_tcpcb_init(tp);
1678 /* Initialize the per-TCPCB log data. */
1679 tcp_log_tcpcbinit(tp);
1681 if (tp->t_fb->tfb_tcp_fb_init) {
1682 (*tp->t_fb->tfb_tcp_fb_init)(tp);
1684 return (tp); /* XXX */
1688 * Switch the congestion control algorithm back to NewReno for any active
1689 * control blocks using an algorithm which is about to go away.
1690 * This ensures the CC framework can allow the unload to proceed without leaving
1691 * any dangling pointers which would trigger a panic.
1692 * Returning non-zero would inform the CC framework that something went wrong
1693 * and it would be unsafe to allow the unload to proceed. However, there is no
1694 * way for this to occur with this implementation so we always return zero.
1697 tcp_ccalgounload(struct cc_algo *unload_algo)
1699 struct cc_algo *tmpalgo;
1702 VNET_ITERATOR_DECL(vnet_iter);
1705 * Check all active control blocks across all network stacks and change
1706 * any that are using "unload_algo" back to NewReno. If "unload_algo"
1707 * requires cleanup code to be run, call it.
1710 VNET_FOREACH(vnet_iter) {
1711 CURVNET_SET(vnet_iter);
1712 INP_INFO_WLOCK(&V_tcbinfo);
1714 * New connections already part way through being initialised
1715 * with the CC algo we're removing will not race with this code
1716 * because the INP_INFO_WLOCK is held during initialisation. We
1717 * therefore don't enter the loop below until the connection
1718 * list has stabilised.
1720 CK_LIST_FOREACH(inp, &V_tcb, inp_list) {
1722 /* Important to skip tcptw structs. */
1723 if (!(inp->inp_flags & INP_TIMEWAIT) &&
1724 (tp = intotcpcb(inp)) != NULL) {
1726 * By holding INP_WLOCK here, we are assured
1727 * that the connection is not currently
1728 * executing inside the CC module's functions
1729 * i.e. it is safe to make the switch back to
1732 if (CC_ALGO(tp) == unload_algo) {
1733 tmpalgo = CC_ALGO(tp);
1734 /* NewReno does not require any init. */
1735 CC_ALGO(tp) = &newreno_cc_algo;
1736 /* XXX defer to epoch_call */
1737 if (tmpalgo->cb_destroy != NULL)
1738 tmpalgo->cb_destroy(tp->ccv);
1743 INP_INFO_WUNLOCK(&V_tcbinfo);
1746 VNET_LIST_RUNLOCK();
1752 * Drop a TCP connection, reporting
1753 * the specified error. If connection is synchronized,
1754 * then send a RST to peer.
1757 tcp_drop(struct tcpcb *tp, int errno)
1759 struct socket *so = tp->t_inpcb->inp_socket;
1761 INP_INFO_LOCK_ASSERT(&V_tcbinfo);
1762 INP_WLOCK_ASSERT(tp->t_inpcb);
1764 if (TCPS_HAVERCVDSYN(tp->t_state)) {
1765 tcp_state_change(tp, TCPS_CLOSED);
1766 (void) tp->t_fb->tfb_tcp_output(tp);
1767 TCPSTAT_INC(tcps_drops);
1769 TCPSTAT_INC(tcps_conndrops);
1770 if (errno == ETIMEDOUT && tp->t_softerror)
1771 errno = tp->t_softerror;
1772 so->so_error = errno;
1773 return (tcp_close(tp));
1777 tcp_discardcb(struct tcpcb *tp)
1779 struct inpcb *inp = tp->t_inpcb;
1780 struct socket *so = inp->inp_socket;
1782 int isipv6 = (inp->inp_vflag & INP_IPV6) != 0;
1784 int released __unused;
1786 INP_WLOCK_ASSERT(inp);
1789 * Make sure that all of our timers are stopped before we delete the
1792 * If stopping a timer fails, we schedule a discard function in same
1793 * callout, and the last discard function called will take care of
1794 * deleting the tcpcb.
1796 tp->t_timers->tt_draincnt = 0;
1797 tcp_timer_stop(tp, TT_REXMT);
1798 tcp_timer_stop(tp, TT_PERSIST);
1799 tcp_timer_stop(tp, TT_KEEP);
1800 tcp_timer_stop(tp, TT_2MSL);
1801 tcp_timer_stop(tp, TT_DELACK);
1802 if (tp->t_fb->tfb_tcp_timer_stop_all) {
1804 * Call the stop-all function of the methods,
1805 * this function should call the tcp_timer_stop()
1806 * method with each of the function specific timeouts.
1807 * That stop will be called via the tfb_tcp_timer_stop()
1808 * which should use the async drain function of the
1809 * callout system (see tcp_var.h).
1811 tp->t_fb->tfb_tcp_timer_stop_all(tp);
1815 * If we got enough samples through the srtt filter,
1816 * save the rtt and rttvar in the routing entry.
1817 * 'Enough' is arbitrarily defined as 4 rtt samples.
1818 * 4 samples is enough for the srtt filter to converge
1819 * to within enough % of the correct value; fewer samples
1820 * and we could save a bogus rtt. The danger is not high
1821 * as tcp quickly recovers from everything.
1822 * XXX: Works very well but needs some more statistics!
1824 if (tp->t_rttupdated >= 4) {
1825 struct hc_metrics_lite metrics;
1828 bzero(&metrics, sizeof(metrics));
1830 * Update the ssthresh always when the conditions below
1831 * are satisfied. This gives us better new start value
1832 * for the congestion avoidance for new connections.
1833 * ssthresh is only set if packet loss occurred on a session.
1835 * XXXRW: 'so' may be NULL here, and/or socket buffer may be
1836 * being torn down. Ideally this code would not use 'so'.
1838 ssthresh = tp->snd_ssthresh;
1839 if (ssthresh != 0 && ssthresh < so->so_snd.sb_hiwat / 2) {
1841 * convert the limit from user data bytes to
1842 * packets then to packet data bytes.
1844 ssthresh = (ssthresh + tp->t_maxseg / 2) / tp->t_maxseg;
1847 ssthresh *= (tp->t_maxseg +
1849 (isipv6 ? sizeof (struct ip6_hdr) +
1850 sizeof (struct tcphdr) :
1852 sizeof (struct tcpiphdr)
1859 metrics.rmx_ssthresh = ssthresh;
1861 metrics.rmx_rtt = tp->t_srtt;
1862 metrics.rmx_rttvar = tp->t_rttvar;
1863 metrics.rmx_cwnd = tp->snd_cwnd;
1864 metrics.rmx_sendpipe = 0;
1865 metrics.rmx_recvpipe = 0;
1867 tcp_hc_update(&inp->inp_inc, &metrics);
1870 /* free the reassembly queue, if any */
1871 tcp_reass_flush(tp);
1874 /* Disconnect offload device, if any. */
1875 if (tp->t_flags & TF_TOE)
1876 tcp_offload_detach(tp);
1879 tcp_free_sackholes(tp);
1882 /* Free the TCP PCAP queues. */
1883 tcp_pcap_drain(&(tp->t_inpkts));
1884 tcp_pcap_drain(&(tp->t_outpkts));
1887 /* Allow the CC algorithm to clean up after itself. */
1888 if (CC_ALGO(tp)->cb_destroy != NULL)
1889 CC_ALGO(tp)->cb_destroy(tp->ccv);
1892 khelp_destroy_osd(tp->osd);
1896 inp->inp_ppcb = NULL;
1897 if (tp->t_timers->tt_draincnt == 0) {
1898 /* We own the last reference on tcpcb, let's free it. */
1900 tcp_log_tcpcbfini(tp);
1902 TCPSTATES_DEC(tp->t_state);
1903 if (tp->t_fb->tfb_tcp_fb_fini)
1904 (*tp->t_fb->tfb_tcp_fb_fini)(tp, 1);
1905 refcount_release(&tp->t_fb->tfb_refcnt);
1907 uma_zfree(V_tcpcb_zone, tp);
1908 released = in_pcbrele_wlocked(inp);
1909 KASSERT(!released, ("%s: inp %p should not have been released "
1910 "here", __func__, inp));
1915 tcp_timer_discard(void *ptp)
1920 tp = (struct tcpcb *)ptp;
1921 CURVNET_SET(tp->t_vnet);
1922 INP_INFO_RLOCK(&V_tcbinfo);
1924 KASSERT(inp != NULL, ("%s: tp %p tp->t_inpcb == NULL",
1927 KASSERT((tp->t_timers->tt_flags & TT_STOPPED) != 0,
1928 ("%s: tcpcb has to be stopped here", __func__));
1929 tp->t_timers->tt_draincnt--;
1930 if (tp->t_timers->tt_draincnt == 0) {
1931 /* We own the last reference on this tcpcb, let's free it. */
1933 tcp_log_tcpcbfini(tp);
1935 TCPSTATES_DEC(tp->t_state);
1936 if (tp->t_fb->tfb_tcp_fb_fini)
1937 (*tp->t_fb->tfb_tcp_fb_fini)(tp, 1);
1938 refcount_release(&tp->t_fb->tfb_refcnt);
1940 uma_zfree(V_tcpcb_zone, tp);
1941 if (in_pcbrele_wlocked(inp)) {
1942 INP_INFO_RUNLOCK(&V_tcbinfo);
1948 INP_INFO_RUNLOCK(&V_tcbinfo);
1953 * Attempt to close a TCP control block, marking it as dropped, and freeing
1954 * the socket if we hold the only reference.
1957 tcp_close(struct tcpcb *tp)
1959 struct inpcb *inp = tp->t_inpcb;
1962 INP_INFO_LOCK_ASSERT(&V_tcbinfo);
1963 INP_WLOCK_ASSERT(inp);
1966 if (tp->t_state == TCPS_LISTEN)
1967 tcp_offload_listen_stop(tp);
1970 * This releases the TFO pending counter resource for TFO listen
1971 * sockets as well as passively-created TFO sockets that transition
1972 * from SYN_RECEIVED to CLOSED.
1974 if (tp->t_tfo_pending) {
1975 tcp_fastopen_decrement_counter(tp->t_tfo_pending);
1976 tp->t_tfo_pending = NULL;
1979 TCPSTAT_INC(tcps_closed);
1980 if (tp->t_state != TCPS_CLOSED)
1981 tcp_state_change(tp, TCPS_CLOSED);
1982 KASSERT(inp->inp_socket != NULL, ("tcp_close: inp_socket NULL"));
1983 so = inp->inp_socket;
1984 soisdisconnected(so);
1985 if (inp->inp_flags & INP_SOCKREF) {
1986 KASSERT(so->so_state & SS_PROTOREF,
1987 ("tcp_close: !SS_PROTOREF"));
1988 inp->inp_flags &= ~INP_SOCKREF;
1991 so->so_state &= ~SS_PROTOREF;
2001 VNET_ITERATOR_DECL(vnet_iter);
2006 VNET_LIST_RLOCK_NOSLEEP();
2007 VNET_FOREACH(vnet_iter) {
2008 CURVNET_SET(vnet_iter);
2013 * Walk the tcpbs, if existing, and flush the reassembly queue,
2014 * if there is one...
2015 * XXX: The "Net/3" implementation doesn't imply that the TCP
2016 * reassembly queue should be flushed, but in a situation
2017 * where we're really low on mbufs, this is potentially
2020 INP_INFO_WLOCK(&V_tcbinfo);
2021 CK_LIST_FOREACH(inpb, V_tcbinfo.ipi_listhead, inp_list) {
2022 if (inpb->inp_flags & INP_TIMEWAIT)
2025 if ((tcpb = intotcpcb(inpb)) != NULL) {
2026 tcp_reass_flush(tcpb);
2027 tcp_clean_sackreport(tcpb);
2029 tcp_log_drain(tcpb);
2032 if (tcp_pcap_aggressive_free) {
2033 /* Free the TCP PCAP queues. */
2034 tcp_pcap_drain(&(tcpb->t_inpkts));
2035 tcp_pcap_drain(&(tcpb->t_outpkts));
2041 INP_INFO_WUNLOCK(&V_tcbinfo);
2044 VNET_LIST_RUNLOCK_NOSLEEP();
2048 * Notify a tcp user of an asynchronous error;
2049 * store error as soft error, but wake up user
2050 * (for now, won't do anything until can select for soft error).
2052 * Do not wake up user since there currently is no mechanism for
2053 * reporting soft errors (yet - a kqueue filter may be added).
2055 static struct inpcb *
2056 tcp_notify(struct inpcb *inp, int error)
2060 INP_INFO_LOCK_ASSERT(&V_tcbinfo);
2061 INP_WLOCK_ASSERT(inp);
2063 if ((inp->inp_flags & INP_TIMEWAIT) ||
2064 (inp->inp_flags & INP_DROPPED))
2067 tp = intotcpcb(inp);
2068 KASSERT(tp != NULL, ("tcp_notify: tp == NULL"));
2071 * Ignore some errors if we are hooked up.
2072 * If connection hasn't completed, has retransmitted several times,
2073 * and receives a second error, give up now. This is better
2074 * than waiting a long time to establish a connection that
2075 * can never complete.
2077 if (tp->t_state == TCPS_ESTABLISHED &&
2078 (error == EHOSTUNREACH || error == ENETUNREACH ||
2079 error == EHOSTDOWN)) {
2080 if (inp->inp_route.ro_rt) {
2081 RTFREE(inp->inp_route.ro_rt);
2082 inp->inp_route.ro_rt = (struct rtentry *)NULL;
2085 } else if (tp->t_state < TCPS_ESTABLISHED && tp->t_rxtshift > 3 &&
2087 tp = tcp_drop(tp, error);
2093 tp->t_softerror = error;
2097 wakeup( &so->so_timeo);
2104 tcp_pcblist(SYSCTL_HANDLER_ARGS)
2106 int error, i, m, n, pcb_count;
2107 struct in_pcblist *il;
2108 struct inpcb *inp, **inp_list;
2113 * The process of preparing the TCB list is too time-consuming and
2114 * resource-intensive to repeat twice on every request.
2116 if (req->oldptr == NULL) {
2117 n = V_tcbinfo.ipi_count +
2118 counter_u64_fetch(V_tcps_states[TCPS_SYN_RECEIVED]);
2119 n += imax(n / 8, 10);
2120 req->oldidx = 2 * (sizeof xig) + n * sizeof(struct xtcpcb);
2124 if (req->newptr != NULL)
2128 * OK, now we're committed to doing something.
2130 INP_LIST_RLOCK(&V_tcbinfo);
2131 gencnt = V_tcbinfo.ipi_gencnt;
2132 n = V_tcbinfo.ipi_count;
2133 INP_LIST_RUNLOCK(&V_tcbinfo);
2135 m = counter_u64_fetch(V_tcps_states[TCPS_SYN_RECEIVED]);
2137 error = sysctl_wire_old_buffer(req, 2 * (sizeof xig)
2138 + (n + m) * sizeof(struct xtcpcb));
2142 xig.xig_len = sizeof xig;
2143 xig.xig_count = n + m;
2144 xig.xig_gen = gencnt;
2145 xig.xig_sogen = so_gencnt;
2146 error = SYSCTL_OUT(req, &xig, sizeof xig);
2150 error = syncache_pcblist(req, m, &pcb_count);
2154 il = malloc(sizeof(struct in_pcblist) + n * sizeof(struct inpcb *), M_TEMP, M_WAITOK|M_ZERO_INVARIANTS);
2155 inp_list = il->il_inp_list;
2157 INP_INFO_WLOCK(&V_tcbinfo);
2158 for (inp = CK_LIST_FIRST(V_tcbinfo.ipi_listhead), i = 0;
2159 inp != NULL && i < n; inp = CK_LIST_NEXT(inp, inp_list)) {
2161 if (inp->inp_gencnt <= gencnt) {
2163 * XXX: This use of cr_cansee(), introduced with
2164 * TCP state changes, is not quite right, but for
2165 * now, better than nothing.
2167 if (inp->inp_flags & INP_TIMEWAIT) {
2168 if (intotw(inp) != NULL)
2169 error = cr_cansee(req->td->td_ucred,
2170 intotw(inp)->tw_cred);
2172 error = EINVAL; /* Skip this inp. */
2174 error = cr_canseeinpcb(req->td->td_ucred, inp);
2177 inp_list[i++] = inp;
2182 INP_INFO_WUNLOCK(&V_tcbinfo);
2186 for (i = 0; i < n; i++) {
2189 if (inp->inp_gencnt <= gencnt) {
2192 tcp_inptoxtp(inp, &xt);
2194 error = SYSCTL_OUT(req, &xt, sizeof xt);
2200 il->il_pcbinfo = &V_tcbinfo;
2201 epoch_call(net_epoch_preempt, &il->il_epoch_ctx, in_pcblist_rele_rlocked);
2205 * Give the user an updated idea of our state.
2206 * If the generation differs from what we told
2207 * her before, she knows that something happened
2208 * while we were processing this request, and it
2209 * might be necessary to retry.
2211 INP_LIST_RLOCK(&V_tcbinfo);
2212 xig.xig_gen = V_tcbinfo.ipi_gencnt;
2213 xig.xig_sogen = so_gencnt;
2214 xig.xig_count = V_tcbinfo.ipi_count + pcb_count;
2215 INP_LIST_RUNLOCK(&V_tcbinfo);
2216 error = SYSCTL_OUT(req, &xig, sizeof xig);
2221 SYSCTL_PROC(_net_inet_tcp, TCPCTL_PCBLIST, pcblist,
2222 CTLTYPE_OPAQUE | CTLFLAG_RD, NULL, 0,
2223 tcp_pcblist, "S,xtcpcb", "List of active TCP connections");
2227 tcp_getcred(SYSCTL_HANDLER_ARGS)
2230 struct sockaddr_in addrs[2];
2234 error = priv_check(req->td, PRIV_NETINET_GETCRED);
2237 error = SYSCTL_IN(req, addrs, sizeof(addrs));
2240 inp = in_pcblookup(&V_tcbinfo, addrs[1].sin_addr, addrs[1].sin_port,
2241 addrs[0].sin_addr, addrs[0].sin_port, INPLOOKUP_RLOCKPCB, NULL);
2243 if (inp->inp_socket == NULL)
2246 error = cr_canseeinpcb(req->td->td_ucred, inp);
2248 cru2x(inp->inp_cred, &xuc);
2253 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred));
2257 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, getcred,
2258 CTLTYPE_OPAQUE|CTLFLAG_RW|CTLFLAG_PRISON, 0, 0,
2259 tcp_getcred, "S,xucred", "Get the xucred of a TCP connection");
2264 tcp6_getcred(SYSCTL_HANDLER_ARGS)
2267 struct sockaddr_in6 addrs[2];
2274 error = priv_check(req->td, PRIV_NETINET_GETCRED);
2277 error = SYSCTL_IN(req, addrs, sizeof(addrs));
2280 if ((error = sa6_embedscope(&addrs[0], V_ip6_use_defzone)) != 0 ||
2281 (error = sa6_embedscope(&addrs[1], V_ip6_use_defzone)) != 0) {
2284 if (IN6_IS_ADDR_V4MAPPED(&addrs[0].sin6_addr)) {
2286 if (IN6_IS_ADDR_V4MAPPED(&addrs[1].sin6_addr))
2295 inp = in_pcblookup(&V_tcbinfo,
2296 *(struct in_addr *)&addrs[1].sin6_addr.s6_addr[12],
2298 *(struct in_addr *)&addrs[0].sin6_addr.s6_addr[12],
2299 addrs[0].sin6_port, INPLOOKUP_RLOCKPCB, NULL);
2302 inp = in6_pcblookup(&V_tcbinfo,
2303 &addrs[1].sin6_addr, addrs[1].sin6_port,
2304 &addrs[0].sin6_addr, addrs[0].sin6_port,
2305 INPLOOKUP_RLOCKPCB, NULL);
2307 if (inp->inp_socket == NULL)
2310 error = cr_canseeinpcb(req->td->td_ucred, inp);
2312 cru2x(inp->inp_cred, &xuc);
2317 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred));
2321 SYSCTL_PROC(_net_inet6_tcp6, OID_AUTO, getcred,
2322 CTLTYPE_OPAQUE|CTLFLAG_RW|CTLFLAG_PRISON, 0, 0,
2323 tcp6_getcred, "S,xucred", "Get the xucred of a TCP6 connection");
2329 tcp_ctlinput(int cmd, struct sockaddr *sa, void *vip)
2331 struct ip *ip = vip;
2333 struct in_addr faddr;
2336 struct inpcb *(*notify)(struct inpcb *, int) = tcp_notify;
2338 struct in_conninfo inc;
2339 tcp_seq icmp_tcp_seq;
2342 faddr = ((struct sockaddr_in *)sa)->sin_addr;
2343 if (sa->sa_family != AF_INET || faddr.s_addr == INADDR_ANY)
2346 if (cmd == PRC_MSGSIZE)
2347 notify = tcp_mtudisc_notify;
2348 else if (V_icmp_may_rst && (cmd == PRC_UNREACH_ADMIN_PROHIB ||
2349 cmd == PRC_UNREACH_PORT || cmd == PRC_UNREACH_PROTOCOL ||
2350 cmd == PRC_TIMXCEED_INTRANS) && ip)
2351 notify = tcp_drop_syn_sent;
2354 * Hostdead is ugly because it goes linearly through all PCBs.
2355 * XXX: We never get this from ICMP, otherwise it makes an
2356 * excellent DoS attack on machines with many connections.
2358 else if (cmd == PRC_HOSTDEAD)
2360 else if ((unsigned)cmd >= PRC_NCMDS || inetctlerrmap[cmd] == 0)
2364 in_pcbnotifyall(&V_tcbinfo, faddr, inetctlerrmap[cmd], notify);
2368 icp = (struct icmp *)((caddr_t)ip - offsetof(struct icmp, icmp_ip));
2369 th = (struct tcphdr *)((caddr_t)ip + (ip->ip_hl << 2));
2370 INP_INFO_RLOCK(&V_tcbinfo);
2371 inp = in_pcblookup(&V_tcbinfo, faddr, th->th_dport, ip->ip_src,
2372 th->th_sport, INPLOOKUP_WLOCKPCB, NULL);
2373 if (inp != NULL && PRC_IS_REDIRECT(cmd)) {
2374 /* signal EHOSTDOWN, as it flushes the cached route */
2375 inp = (*notify)(inp, EHOSTDOWN);
2378 icmp_tcp_seq = th->th_seq;
2380 if (!(inp->inp_flags & INP_TIMEWAIT) &&
2381 !(inp->inp_flags & INP_DROPPED) &&
2382 !(inp->inp_socket == NULL)) {
2383 tp = intotcpcb(inp);
2384 if (SEQ_GEQ(ntohl(icmp_tcp_seq), tp->snd_una) &&
2385 SEQ_LT(ntohl(icmp_tcp_seq), tp->snd_max)) {
2386 if (cmd == PRC_MSGSIZE) {
2389 * If we got a needfrag set the MTU
2390 * in the route to the suggested new
2391 * value (if given) and then notify.
2393 mtu = ntohs(icp->icmp_nextmtu);
2395 * If no alternative MTU was
2396 * proposed, try the next smaller
2401 ntohs(ip->ip_len), 1);
2402 if (mtu < V_tcp_minmss +
2403 sizeof(struct tcpiphdr))
2404 mtu = V_tcp_minmss +
2405 sizeof(struct tcpiphdr);
2407 * Only process the offered MTU if it
2408 * is smaller than the current one.
2410 if (mtu < tp->t_maxseg +
2411 sizeof(struct tcpiphdr)) {
2412 bzero(&inc, sizeof(inc));
2413 inc.inc_faddr = faddr;
2415 inp->inp_inc.inc_fibnum;
2416 tcp_hc_updatemtu(&inc, mtu);
2417 tcp_mtudisc(inp, mtu);
2420 inp = (*notify)(inp,
2421 inetctlerrmap[cmd]);
2425 bzero(&inc, sizeof(inc));
2426 inc.inc_fport = th->th_dport;
2427 inc.inc_lport = th->th_sport;
2428 inc.inc_faddr = faddr;
2429 inc.inc_laddr = ip->ip_src;
2430 syncache_unreach(&inc, icmp_tcp_seq);
2435 INP_INFO_RUNLOCK(&V_tcbinfo);
2441 tcp6_ctlinput(int cmd, struct sockaddr *sa, void *d)
2443 struct in6_addr *dst;
2444 struct inpcb *(*notify)(struct inpcb *, int) = tcp_notify;
2445 struct ip6_hdr *ip6;
2449 struct icmp6_hdr *icmp6;
2450 struct ip6ctlparam *ip6cp = NULL;
2451 const struct sockaddr_in6 *sa6_src = NULL;
2452 struct in_conninfo inc;
2457 tcp_seq icmp_tcp_seq;
2461 if (sa->sa_family != AF_INET6 ||
2462 sa->sa_len != sizeof(struct sockaddr_in6))
2465 /* if the parameter is from icmp6, decode it. */
2467 ip6cp = (struct ip6ctlparam *)d;
2468 icmp6 = ip6cp->ip6c_icmp6;
2470 ip6 = ip6cp->ip6c_ip6;
2471 off = ip6cp->ip6c_off;
2472 sa6_src = ip6cp->ip6c_src;
2473 dst = ip6cp->ip6c_finaldst;
2477 off = 0; /* fool gcc */
2482 if (cmd == PRC_MSGSIZE)
2483 notify = tcp_mtudisc_notify;
2484 else if (V_icmp_may_rst && (cmd == PRC_UNREACH_ADMIN_PROHIB ||
2485 cmd == PRC_UNREACH_PORT || cmd == PRC_UNREACH_PROTOCOL ||
2486 cmd == PRC_TIMXCEED_INTRANS) && ip6 != NULL)
2487 notify = tcp_drop_syn_sent;
2490 * Hostdead is ugly because it goes linearly through all PCBs.
2491 * XXX: We never get this from ICMP, otherwise it makes an
2492 * excellent DoS attack on machines with many connections.
2494 else if (cmd == PRC_HOSTDEAD)
2496 else if ((unsigned)cmd >= PRC_NCMDS || inet6ctlerrmap[cmd] == 0)
2500 in6_pcbnotify(&V_tcbinfo, sa, 0,
2501 (const struct sockaddr *)sa6_src,
2502 0, cmd, NULL, notify);
2506 /* Check if we can safely get the ports from the tcp hdr */
2509 (int32_t) (off + sizeof(struct tcp_ports)))) {
2512 bzero(&t_ports, sizeof(struct tcp_ports));
2513 m_copydata(m, off, sizeof(struct tcp_ports), (caddr_t)&t_ports);
2514 INP_INFO_RLOCK(&V_tcbinfo);
2515 inp = in6_pcblookup(&V_tcbinfo, &ip6->ip6_dst, t_ports.th_dport,
2516 &ip6->ip6_src, t_ports.th_sport, INPLOOKUP_WLOCKPCB, NULL);
2517 if (inp != NULL && PRC_IS_REDIRECT(cmd)) {
2518 /* signal EHOSTDOWN, as it flushes the cached route */
2519 inp = (*notify)(inp, EHOSTDOWN);
2522 off += sizeof(struct tcp_ports);
2523 if (m->m_pkthdr.len < (int32_t) (off + sizeof(tcp_seq))) {
2526 m_copydata(m, off, sizeof(tcp_seq), (caddr_t)&icmp_tcp_seq);
2528 if (!(inp->inp_flags & INP_TIMEWAIT) &&
2529 !(inp->inp_flags & INP_DROPPED) &&
2530 !(inp->inp_socket == NULL)) {
2531 tp = intotcpcb(inp);
2532 if (SEQ_GEQ(ntohl(icmp_tcp_seq), tp->snd_una) &&
2533 SEQ_LT(ntohl(icmp_tcp_seq), tp->snd_max)) {
2534 if (cmd == PRC_MSGSIZE) {
2537 * If we got a needfrag set the MTU
2538 * in the route to the suggested new
2539 * value (if given) and then notify.
2541 mtu = ntohl(icmp6->icmp6_mtu);
2543 * If no alternative MTU was
2544 * proposed, or the proposed
2545 * MTU was too small, set to
2548 if (mtu < IPV6_MMTU)
2549 mtu = IPV6_MMTU - 8;
2550 bzero(&inc, sizeof(inc));
2551 inc.inc_fibnum = M_GETFIB(m);
2552 inc.inc_flags |= INC_ISIPV6;
2553 inc.inc6_faddr = *dst;
2554 if (in6_setscope(&inc.inc6_faddr,
2555 m->m_pkthdr.rcvif, NULL))
2558 * Only process the offered MTU if it
2559 * is smaller than the current one.
2561 if (mtu < tp->t_maxseg +
2562 sizeof (struct tcphdr) +
2563 sizeof (struct ip6_hdr)) {
2564 tcp_hc_updatemtu(&inc, mtu);
2565 tcp_mtudisc(inp, mtu);
2566 ICMP6STAT_INC(icp6s_pmtuchg);
2569 inp = (*notify)(inp,
2570 inet6ctlerrmap[cmd]);
2574 bzero(&inc, sizeof(inc));
2575 inc.inc_fibnum = M_GETFIB(m);
2576 inc.inc_flags |= INC_ISIPV6;
2577 inc.inc_fport = t_ports.th_dport;
2578 inc.inc_lport = t_ports.th_sport;
2579 inc.inc6_faddr = *dst;
2580 inc.inc6_laddr = ip6->ip6_src;
2581 syncache_unreach(&inc, icmp_tcp_seq);
2586 INP_INFO_RUNLOCK(&V_tcbinfo);
2592 * Following is where TCP initial sequence number generation occurs.
2594 * There are two places where we must use initial sequence numbers:
2595 * 1. In SYN-ACK packets.
2596 * 2. In SYN packets.
2598 * All ISNs for SYN-ACK packets are generated by the syncache. See
2599 * tcp_syncache.c for details.
2601 * The ISNs in SYN packets must be monotonic; TIME_WAIT recycling
2602 * depends on this property. In addition, these ISNs should be
2603 * unguessable so as to prevent connection hijacking. To satisfy
2604 * the requirements of this situation, the algorithm outlined in
2605 * RFC 1948 is used, with only small modifications.
2607 * Implementation details:
2609 * Time is based off the system timer, and is corrected so that it
2610 * increases by one megabyte per second. This allows for proper
2611 * recycling on high speed LANs while still leaving over an hour
2614 * As reading the *exact* system time is too expensive to be done
2615 * whenever setting up a TCP connection, we increment the time
2616 * offset in two ways. First, a small random positive increment
2617 * is added to isn_offset for each connection that is set up.
2618 * Second, the function tcp_isn_tick fires once per clock tick
2619 * and increments isn_offset as necessary so that sequence numbers
2620 * are incremented at approximately ISN_BYTES_PER_SECOND. The
2621 * random positive increments serve only to ensure that the same
2622 * exact sequence number is never sent out twice (as could otherwise
2623 * happen when a port is recycled in less than the system tick
2626 * net.inet.tcp.isn_reseed_interval controls the number of seconds
2627 * between seeding of isn_secret. This is normally set to zero,
2628 * as reseeding should not be necessary.
2630 * Locking of the global variables isn_secret, isn_last_reseed, isn_offset,
2631 * isn_offset_old, and isn_ctx is performed using the TCP pcbinfo lock. In
2632 * general, this means holding an exclusive (write) lock.
2635 #define ISN_BYTES_PER_SECOND 1048576
2636 #define ISN_STATIC_INCREMENT 4096
2637 #define ISN_RANDOM_INCREMENT (4096 - 1)
2639 static VNET_DEFINE(u_char, isn_secret[32]);
2640 static VNET_DEFINE(int, isn_last);
2641 static VNET_DEFINE(int, isn_last_reseed);
2642 static VNET_DEFINE(u_int32_t, isn_offset);
2643 static VNET_DEFINE(u_int32_t, isn_offset_old);
2645 #define V_isn_secret VNET(isn_secret)
2646 #define V_isn_last VNET(isn_last)
2647 #define V_isn_last_reseed VNET(isn_last_reseed)
2648 #define V_isn_offset VNET(isn_offset)
2649 #define V_isn_offset_old VNET(isn_offset_old)
2652 tcp_new_isn(struct tcpcb *tp)
2655 u_int32_t md5_buffer[4];
2657 u_int32_t projected_offset;
2659 INP_WLOCK_ASSERT(tp->t_inpcb);
2662 /* Seed if this is the first use, reseed if requested. */
2663 if ((V_isn_last_reseed == 0) || ((V_tcp_isn_reseed_interval > 0) &&
2664 (((u_int)V_isn_last_reseed + (u_int)V_tcp_isn_reseed_interval*hz)
2666 read_random(&V_isn_secret, sizeof(V_isn_secret));
2667 V_isn_last_reseed = ticks;
2670 /* Compute the md5 hash and return the ISN. */
2672 MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->inp_fport, sizeof(u_short));
2673 MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->inp_lport, sizeof(u_short));
2675 if ((tp->t_inpcb->inp_vflag & INP_IPV6) != 0) {
2676 MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->in6p_faddr,
2677 sizeof(struct in6_addr));
2678 MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->in6p_laddr,
2679 sizeof(struct in6_addr));
2683 MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->inp_faddr,
2684 sizeof(struct in_addr));
2685 MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->inp_laddr,
2686 sizeof(struct in_addr));
2688 MD5Update(&isn_ctx, (u_char *) &V_isn_secret, sizeof(V_isn_secret));
2689 MD5Final((u_char *) &md5_buffer, &isn_ctx);
2690 new_isn = (tcp_seq) md5_buffer[0];
2691 V_isn_offset += ISN_STATIC_INCREMENT +
2692 (arc4random() & ISN_RANDOM_INCREMENT);
2693 if (ticks != V_isn_last) {
2694 projected_offset = V_isn_offset_old +
2695 ISN_BYTES_PER_SECOND / hz * (ticks - V_isn_last);
2696 if (SEQ_GT(projected_offset, V_isn_offset))
2697 V_isn_offset = projected_offset;
2698 V_isn_offset_old = V_isn_offset;
2701 new_isn += V_isn_offset;
2707 * When a specific ICMP unreachable message is received and the
2708 * connection state is SYN-SENT, drop the connection. This behavior
2709 * is controlled by the icmp_may_rst sysctl.
2712 tcp_drop_syn_sent(struct inpcb *inp, int errno)
2716 INP_INFO_RLOCK_ASSERT(&V_tcbinfo);
2717 INP_WLOCK_ASSERT(inp);
2719 if ((inp->inp_flags & INP_TIMEWAIT) ||
2720 (inp->inp_flags & INP_DROPPED))
2723 tp = intotcpcb(inp);
2724 if (tp->t_state != TCPS_SYN_SENT)
2727 if (IS_FASTOPEN(tp->t_flags))
2728 tcp_fastopen_disable_path(tp);
2730 tp = tcp_drop(tp, errno);
2738 * When `need fragmentation' ICMP is received, update our idea of the MSS
2739 * based on the new value. Also nudge TCP to send something, since we
2740 * know the packet we just sent was dropped.
2741 * This duplicates some code in the tcp_mss() function in tcp_input.c.
2743 static struct inpcb *
2744 tcp_mtudisc_notify(struct inpcb *inp, int error)
2747 tcp_mtudisc(inp, -1);
2752 tcp_mtudisc(struct inpcb *inp, int mtuoffer)
2757 INP_WLOCK_ASSERT(inp);
2758 if ((inp->inp_flags & INP_TIMEWAIT) ||
2759 (inp->inp_flags & INP_DROPPED))
2762 tp = intotcpcb(inp);
2763 KASSERT(tp != NULL, ("tcp_mtudisc: tp == NULL"));
2765 tcp_mss_update(tp, -1, mtuoffer, NULL, NULL);
2767 so = inp->inp_socket;
2768 SOCKBUF_LOCK(&so->so_snd);
2769 /* If the mss is larger than the socket buffer, decrease the mss. */
2770 if (so->so_snd.sb_hiwat < tp->t_maxseg)
2771 tp->t_maxseg = so->so_snd.sb_hiwat;
2772 SOCKBUF_UNLOCK(&so->so_snd);
2774 TCPSTAT_INC(tcps_mturesent);
2776 tp->snd_nxt = tp->snd_una;
2777 tcp_free_sackholes(tp);
2778 tp->snd_recover = tp->snd_max;
2779 if (tp->t_flags & TF_SACK_PERMIT)
2780 EXIT_FASTRECOVERY(tp->t_flags);
2781 tp->t_fb->tfb_tcp_output(tp);
2786 * Look-up the routing entry to the peer of this inpcb. If no route
2787 * is found and it cannot be allocated, then return 0. This routine
2788 * is called by TCP routines that access the rmx structure and by
2789 * tcp_mss_update to get the peer/interface MTU.
2792 tcp_maxmtu(struct in_conninfo *inc, struct tcp_ifcap *cap)
2794 struct nhop4_extended nh4;
2796 uint32_t maxmtu = 0;
2798 KASSERT(inc != NULL, ("tcp_maxmtu with NULL in_conninfo pointer"));
2800 if (inc->inc_faddr.s_addr != INADDR_ANY) {
2802 if (fib4_lookup_nh_ext(inc->inc_fibnum, inc->inc_faddr,
2803 NHR_REF, 0, &nh4) != 0)
2807 maxmtu = nh4.nh_mtu;
2809 /* Report additional interface capabilities. */
2811 if (ifp->if_capenable & IFCAP_TSO4 &&
2812 ifp->if_hwassist & CSUM_TSO) {
2813 cap->ifcap |= CSUM_TSO;
2814 cap->tsomax = ifp->if_hw_tsomax;
2815 cap->tsomaxsegcount = ifp->if_hw_tsomaxsegcount;
2816 cap->tsomaxsegsize = ifp->if_hw_tsomaxsegsize;
2819 fib4_free_nh_ext(inc->inc_fibnum, &nh4);
2827 tcp_maxmtu6(struct in_conninfo *inc, struct tcp_ifcap *cap)
2829 struct nhop6_extended nh6;
2830 struct in6_addr dst6;
2833 uint32_t maxmtu = 0;
2835 KASSERT(inc != NULL, ("tcp_maxmtu6 with NULL in_conninfo pointer"));
2837 if (!IN6_IS_ADDR_UNSPECIFIED(&inc->inc6_faddr)) {
2838 in6_splitscope(&inc->inc6_faddr, &dst6, &scopeid);
2839 if (fib6_lookup_nh_ext(inc->inc_fibnum, &dst6, scopeid, 0,
2844 maxmtu = nh6.nh_mtu;
2846 /* Report additional interface capabilities. */
2848 if (ifp->if_capenable & IFCAP_TSO6 &&
2849 ifp->if_hwassist & CSUM_TSO) {
2850 cap->ifcap |= CSUM_TSO;
2851 cap->tsomax = ifp->if_hw_tsomax;
2852 cap->tsomaxsegcount = ifp->if_hw_tsomaxsegcount;
2853 cap->tsomaxsegsize = ifp->if_hw_tsomaxsegsize;
2856 fib6_free_nh_ext(inc->inc_fibnum, &nh6);
2864 * Calculate effective SMSS per RFC5681 definition for a given TCP
2865 * connection at its current state, taking into account SACK and etc.
2868 tcp_maxseg(const struct tcpcb *tp)
2872 if (tp->t_flags & TF_NOOPT)
2873 return (tp->t_maxseg);
2876 * Here we have a simplified code from tcp_addoptions(),
2877 * without a proper loop, and having most of paddings hardcoded.
2878 * We might make mistakes with padding here in some edge cases,
2879 * but this is harmless, since result of tcp_maxseg() is used
2880 * only in cwnd and ssthresh estimations.
2882 #define PAD(len) ((((len) / 4) + !!((len) % 4)) * 4)
2883 if (TCPS_HAVEESTABLISHED(tp->t_state)) {
2884 if (tp->t_flags & TF_RCVD_TSTMP)
2885 optlen = TCPOLEN_TSTAMP_APPA;
2888 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE)
2889 if (tp->t_flags & TF_SIGNATURE)
2890 optlen += PAD(TCPOLEN_SIGNATURE);
2892 if ((tp->t_flags & TF_SACK_PERMIT) && tp->rcv_numsacks > 0) {
2893 optlen += TCPOLEN_SACKHDR;
2894 optlen += tp->rcv_numsacks * TCPOLEN_SACK;
2895 optlen = PAD(optlen);
2898 if (tp->t_flags & TF_REQ_TSTMP)
2899 optlen = TCPOLEN_TSTAMP_APPA;
2901 optlen = PAD(TCPOLEN_MAXSEG);
2902 if (tp->t_flags & TF_REQ_SCALE)
2903 optlen += PAD(TCPOLEN_WINDOW);
2904 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE)
2905 if (tp->t_flags & TF_SIGNATURE)
2906 optlen += PAD(TCPOLEN_SIGNATURE);
2908 if (tp->t_flags & TF_SACK_PERMIT)
2909 optlen += PAD(TCPOLEN_SACK_PERMITTED);
2912 optlen = min(optlen, TCP_MAXOLEN);
2913 return (tp->t_maxseg - optlen);
2917 sysctl_drop(SYSCTL_HANDLER_ARGS)
2919 /* addrs[0] is a foreign socket, addrs[1] is a local one. */
2920 struct sockaddr_storage addrs[2];
2924 struct sockaddr_in *fin, *lin;
2926 struct sockaddr_in6 *fin6, *lin6;
2937 if (req->oldptr != NULL || req->oldlen != 0)
2939 if (req->newptr == NULL)
2941 if (req->newlen < sizeof(addrs))
2943 error = SYSCTL_IN(req, &addrs, sizeof(addrs));
2947 switch (addrs[0].ss_family) {
2950 fin6 = (struct sockaddr_in6 *)&addrs[0];
2951 lin6 = (struct sockaddr_in6 *)&addrs[1];
2952 if (fin6->sin6_len != sizeof(struct sockaddr_in6) ||
2953 lin6->sin6_len != sizeof(struct sockaddr_in6))
2955 if (IN6_IS_ADDR_V4MAPPED(&fin6->sin6_addr)) {
2956 if (!IN6_IS_ADDR_V4MAPPED(&lin6->sin6_addr))
2958 in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[0]);
2959 in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[1]);
2960 fin = (struct sockaddr_in *)&addrs[0];
2961 lin = (struct sockaddr_in *)&addrs[1];
2964 error = sa6_embedscope(fin6, V_ip6_use_defzone);
2967 error = sa6_embedscope(lin6, V_ip6_use_defzone);
2974 fin = (struct sockaddr_in *)&addrs[0];
2975 lin = (struct sockaddr_in *)&addrs[1];
2976 if (fin->sin_len != sizeof(struct sockaddr_in) ||
2977 lin->sin_len != sizeof(struct sockaddr_in))
2984 INP_INFO_RLOCK(&V_tcbinfo);
2985 switch (addrs[0].ss_family) {
2988 inp = in6_pcblookup(&V_tcbinfo, &fin6->sin6_addr,
2989 fin6->sin6_port, &lin6->sin6_addr, lin6->sin6_port,
2990 INPLOOKUP_WLOCKPCB, NULL);
2995 inp = in_pcblookup(&V_tcbinfo, fin->sin_addr, fin->sin_port,
2996 lin->sin_addr, lin->sin_port, INPLOOKUP_WLOCKPCB, NULL);
3001 if (inp->inp_flags & INP_TIMEWAIT) {
3003 * XXXRW: There currently exists a state where an
3004 * inpcb is present, but its timewait state has been
3005 * discarded. For now, don't allow dropping of this
3013 } else if (!(inp->inp_flags & INP_DROPPED) &&
3014 !(inp->inp_socket->so_options & SO_ACCEPTCONN)) {
3015 tp = intotcpcb(inp);
3016 tp = tcp_drop(tp, ECONNABORTED);
3023 INP_INFO_RUNLOCK(&V_tcbinfo);
3027 SYSCTL_PROC(_net_inet_tcp, TCPCTL_DROP, drop,
3028 CTLFLAG_VNET | CTLTYPE_STRUCT | CTLFLAG_WR | CTLFLAG_SKIP, NULL,
3029 0, sysctl_drop, "", "Drop TCP connection");
3032 * Generate a standardized TCP log line for use throughout the
3033 * tcp subsystem. Memory allocation is done with M_NOWAIT to
3034 * allow use in the interrupt context.
3036 * NB: The caller MUST free(s, M_TCPLOG) the returned string.
3037 * NB: The function may return NULL if memory allocation failed.
3039 * Due to header inclusion and ordering limitations the struct ip
3040 * and ip6_hdr pointers have to be passed as void pointers.
3043 tcp_log_vain(struct in_conninfo *inc, struct tcphdr *th, void *ip4hdr,
3047 /* Is logging enabled? */
3048 if (tcp_log_in_vain == 0)
3051 return (tcp_log_addr(inc, th, ip4hdr, ip6hdr));
3055 tcp_log_addrs(struct in_conninfo *inc, struct tcphdr *th, void *ip4hdr,
3059 /* Is logging enabled? */
3060 if (tcp_log_debug == 0)
3063 return (tcp_log_addr(inc, th, ip4hdr, ip6hdr));
3067 tcp_log_addr(struct in_conninfo *inc, struct tcphdr *th, void *ip4hdr,
3074 const struct ip6_hdr *ip6;
3076 ip6 = (const struct ip6_hdr *)ip6hdr;
3078 ip = (struct ip *)ip4hdr;
3081 * The log line looks like this:
3082 * "TCP: [1.2.3.4]:50332 to [1.2.3.4]:80 tcpflags 0x2<SYN>"
3084 size = sizeof("TCP: []:12345 to []:12345 tcpflags 0x2<>") +
3085 sizeof(PRINT_TH_FLAGS) + 1 +
3087 2 * INET6_ADDRSTRLEN;
3089 2 * INET_ADDRSTRLEN;
3092 s = malloc(size, M_TCPLOG, M_ZERO|M_NOWAIT);
3096 strcat(s, "TCP: [");
3099 if (inc && ((inc->inc_flags & INC_ISIPV6) == 0)) {
3100 inet_ntoa_r(inc->inc_faddr, sp);
3102 sprintf(sp, "]:%i to [", ntohs(inc->inc_fport));
3104 inet_ntoa_r(inc->inc_laddr, sp);
3106 sprintf(sp, "]:%i", ntohs(inc->inc_lport));
3109 ip6_sprintf(sp, &inc->inc6_faddr);
3111 sprintf(sp, "]:%i to [", ntohs(inc->inc_fport));
3113 ip6_sprintf(sp, &inc->inc6_laddr);
3115 sprintf(sp, "]:%i", ntohs(inc->inc_lport));
3116 } else if (ip6 && th) {
3117 ip6_sprintf(sp, &ip6->ip6_src);
3119 sprintf(sp, "]:%i to [", ntohs(th->th_sport));
3121 ip6_sprintf(sp, &ip6->ip6_dst);
3123 sprintf(sp, "]:%i", ntohs(th->th_dport));
3126 } else if (ip && th) {
3127 inet_ntoa_r(ip->ip_src, sp);
3129 sprintf(sp, "]:%i to [", ntohs(th->th_sport));
3131 inet_ntoa_r(ip->ip_dst, sp);
3133 sprintf(sp, "]:%i", ntohs(th->th_dport));
3141 sprintf(sp, " tcpflags 0x%b", th->th_flags, PRINT_TH_FLAGS);
3142 if (*(s + size - 1) != '\0')
3143 panic("%s: string too long", __func__);
3148 * A subroutine which makes it easy to track TCP state changes with DTrace.
3149 * This function shouldn't be called for t_state initializations that don't
3150 * correspond to actual TCP state transitions.
3153 tcp_state_change(struct tcpcb *tp, int newstate)
3155 #if defined(KDTRACE_HOOKS)
3156 int pstate = tp->t_state;
3159 TCPSTATES_DEC(tp->t_state);
3160 TCPSTATES_INC(newstate);
3161 tp->t_state = newstate;
3162 TCP_PROBE6(state__change, NULL, tp, NULL, tp, NULL, pstate);
3166 * Create an external-format (``xtcpcb'') structure using the information in
3167 * the kernel-format tcpcb structure pointed to by tp. This is done to
3168 * reduce the spew of irrelevant information over this interface, to isolate
3169 * user code from changes in the kernel structure, and potentially to provide
3170 * information-hiding if we decide that some of this information should be
3171 * hidden from users.
3174 tcp_inptoxtp(const struct inpcb *inp, struct xtcpcb *xt)
3176 struct tcpcb *tp = intotcpcb(inp);
3179 if (inp->inp_flags & INP_TIMEWAIT) {
3180 bzero(xt, sizeof(struct xtcpcb));
3181 xt->t_state = TCPS_TIME_WAIT;
3183 xt->t_state = tp->t_state;
3184 xt->t_logstate = tp->t_logstate;
3185 xt->t_flags = tp->t_flags;
3186 xt->t_sndzerowin = tp->t_sndzerowin;
3187 xt->t_sndrexmitpack = tp->t_sndrexmitpack;
3188 xt->t_rcvoopack = tp->t_rcvoopack;
3190 now = getsbinuptime();
3191 #define COPYTIMER(ttt) do { \
3192 if (callout_active(&tp->t_timers->ttt)) \
3193 xt->ttt = (tp->t_timers->ttt.c_time - now) / \
3198 COPYTIMER(tt_delack);
3199 COPYTIMER(tt_rexmt);
3200 COPYTIMER(tt_persist);
3204 xt->t_rcvtime = 1000 * (ticks - tp->t_rcvtime) / hz;
3206 bcopy(tp->t_fb->tfb_tcp_block_name, xt->xt_stack,
3207 TCP_FUNCTION_NAME_LEN_MAX);
3208 bzero(xt->xt_logid, TCP_LOG_ID_LEN);
3210 (void)tcp_log_get_id(tp, xt->xt_logid);
3214 xt->xt_len = sizeof(struct xtcpcb);
3215 in_pcbtoxinpcb(inp, &xt->xt_inp);
3216 if (inp->inp_socket == NULL)
3217 xt->xt_inp.xi_socket.xso_protocol = IPPROTO_TCP;