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);
946 VNET_FOREACH(vnet_iter) {
947 CURVNET_SET(vnet_iter);
948 INP_INFO_WLOCK(&V_tcbinfo);
949 LIST_FOREACH(inp, V_tcbinfo.ipi_listhead, inp_list) {
951 if (inp->inp_flags & INP_TIMEWAIT) {
956 if (tp == NULL || tp->t_fb != blk) {
960 tcp_switch_back_to_default(tp);
963 INP_INFO_WUNLOCK(&V_tcbinfo);
968 rw_wlock(&tcp_function_lock);
970 if (blk->tfb_refcnt) {
971 /* TCBs still attached. */
972 rw_wunlock(&tcp_function_lock);
977 rw_wunlock(&tcp_function_lock);
980 /* Remove any function names that map to this function block. */
981 while (find_tcp_fb_locked(blk, &f) != NULL) {
982 TAILQ_REMOVE(&t_functions, f, tf_next);
985 free(f, M_TCPFUNCTIONS);
987 rw_wunlock(&tcp_function_lock);
994 const char *tcbhash_tuneable;
997 tcbhash_tuneable = "net.inet.tcp.tcbhashsize";
1000 if (hhook_head_register(HHOOK_TYPE_TCP, HHOOK_TCP_EST_IN,
1001 &V_tcp_hhh[HHOOK_TCP_EST_IN], HHOOK_NOWAIT|HHOOK_HEADISINVNET) != 0)
1002 printf("%s: WARNING: unable to register helper hook\n", __func__);
1003 if (hhook_head_register(HHOOK_TYPE_TCP, HHOOK_TCP_EST_OUT,
1004 &V_tcp_hhh[HHOOK_TCP_EST_OUT], HHOOK_NOWAIT|HHOOK_HEADISINVNET) != 0)
1005 printf("%s: WARNING: unable to register helper hook\n", __func__);
1007 hashsize = TCBHASHSIZE;
1008 TUNABLE_INT_FETCH(tcbhash_tuneable, &hashsize);
1009 if (hashsize == 0) {
1011 * Auto tune the hash size based on maxsockets.
1012 * A perfect hash would have a 1:1 mapping
1013 * (hashsize = maxsockets) however it's been
1014 * suggested that O(2) average is better.
1016 hashsize = maketcp_hashsize(maxsockets / 4);
1018 * Our historical default is 512,
1019 * do not autotune lower than this.
1023 if (bootverbose && IS_DEFAULT_VNET(curvnet))
1024 printf("%s: %s auto tuned to %d\n", __func__,
1025 tcbhash_tuneable, hashsize);
1028 * We require a hashsize to be a power of two.
1029 * Previously if it was not a power of two we would just reset it
1030 * back to 512, which could be a nasty surprise if you did not notice
1031 * the error message.
1032 * Instead what we do is clip it to the closest power of two lower
1033 * than the specified hash value.
1035 if (!powerof2(hashsize)) {
1036 int oldhashsize = hashsize;
1038 hashsize = maketcp_hashsize(hashsize);
1039 /* prevent absurdly low value */
1042 printf("%s: WARNING: TCB hash size not a power of 2, "
1043 "clipped from %d to %d.\n", __func__, oldhashsize,
1046 in_pcbinfo_init(&V_tcbinfo, "tcp", &V_tcb, hashsize, hashsize,
1047 "tcp_inpcb", tcp_inpcb_init, IPI_HASHFIELDS_4TUPLE);
1050 * These have to be type stable for the benefit of the timers.
1052 V_tcpcb_zone = uma_zcreate("tcpcb", sizeof(struct tcpcb_mem),
1053 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
1054 uma_zone_set_max(V_tcpcb_zone, maxsockets);
1055 uma_zone_set_warning(V_tcpcb_zone, "kern.ipc.maxsockets limit reached");
1061 TUNABLE_INT_FETCH("net.inet.tcp.sack.enable", &V_tcp_do_sack);
1062 V_sack_hole_zone = uma_zcreate("sackhole", sizeof(struct sackhole),
1063 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
1065 tcp_fastopen_init();
1067 /* Skip initialization of globals for non-default instances. */
1068 if (!IS_DEFAULT_VNET(curvnet))
1071 tcp_reass_global_init();
1073 /* XXX virtualize those bellow? */
1074 tcp_delacktime = TCPTV_DELACK;
1075 tcp_keepinit = TCPTV_KEEP_INIT;
1076 tcp_keepidle = TCPTV_KEEP_IDLE;
1077 tcp_keepintvl = TCPTV_KEEPINTVL;
1078 tcp_maxpersistidle = TCPTV_KEEP_IDLE;
1079 tcp_msl = TCPTV_MSL;
1080 tcp_rexmit_min = TCPTV_MIN;
1081 if (tcp_rexmit_min < 1)
1083 tcp_persmin = TCPTV_PERSMIN;
1084 tcp_persmax = TCPTV_PERSMAX;
1085 tcp_rexmit_slop = TCPTV_CPU_VAR;
1086 tcp_finwait2_timeout = TCPTV_FINWAIT2_TIMEOUT;
1087 tcp_tcbhashsize = hashsize;
1088 /* Setup the tcp function block list */
1089 init_tcp_functions();
1090 register_tcp_functions(&tcp_def_funcblk, M_WAITOK);
1092 /* Initialize the TCP logging data. */
1096 if (tcp_soreceive_stream) {
1098 tcp_usrreqs.pru_soreceive = soreceive_stream;
1101 tcp6_usrreqs.pru_soreceive = soreceive_stream;
1106 #define TCP_MINPROTOHDR (sizeof(struct ip6_hdr) + sizeof(struct tcphdr))
1108 #define TCP_MINPROTOHDR (sizeof(struct tcpiphdr))
1110 if (max_protohdr < TCP_MINPROTOHDR)
1111 max_protohdr = TCP_MINPROTOHDR;
1112 if (max_linkhdr + TCP_MINPROTOHDR > MHLEN)
1114 #undef TCP_MINPROTOHDR
1117 EVENTHANDLER_REGISTER(shutdown_pre_sync, tcp_fini, NULL,
1118 SHUTDOWN_PRI_DEFAULT);
1119 EVENTHANDLER_REGISTER(maxsockets_change, tcp_zone_change, NULL,
1120 EVENTHANDLER_PRI_ANY);
1128 tcp_destroy(void *unused __unused)
1136 * All our processes are gone, all our sockets should be cleaned
1137 * up, which means, we should be past the tcp_discardcb() calls.
1138 * Sleep to let all tcpcb timers really disappear and cleanup.
1141 INP_LIST_RLOCK(&V_tcbinfo);
1142 n = V_tcbinfo.ipi_count;
1143 INP_LIST_RUNLOCK(&V_tcbinfo);
1146 pause("tcpdes", hz / 10);
1151 in_pcbinfo_destroy(&V_tcbinfo);
1152 /* tcp_discardcb() clears the sack_holes up. */
1153 uma_zdestroy(V_sack_hole_zone);
1154 uma_zdestroy(V_tcpcb_zone);
1157 * Cannot free the zone until all tcpcbs are released as we attach
1158 * the allocations to them.
1160 tcp_fastopen_destroy();
1163 error = hhook_head_deregister(V_tcp_hhh[HHOOK_TCP_EST_IN]);
1165 printf("%s: WARNING: unable to deregister helper hook "
1166 "type=%d, id=%d: error %d returned\n", __func__,
1167 HHOOK_TYPE_TCP, HHOOK_TCP_EST_IN, error);
1169 error = hhook_head_deregister(V_tcp_hhh[HHOOK_TCP_EST_OUT]);
1171 printf("%s: WARNING: unable to deregister helper hook "
1172 "type=%d, id=%d: error %d returned\n", __func__,
1173 HHOOK_TYPE_TCP, HHOOK_TCP_EST_OUT, error);
1177 VNET_SYSUNINIT(tcp, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH, tcp_destroy, NULL);
1187 * Fill in the IP and TCP headers for an outgoing packet, given the tcpcb.
1188 * tcp_template used to store this data in mbufs, but we now recopy it out
1189 * of the tcpcb each time to conserve mbufs.
1192 tcpip_fillheaders(struct inpcb *inp, void *ip_ptr, void *tcp_ptr)
1194 struct tcphdr *th = (struct tcphdr *)tcp_ptr;
1196 INP_WLOCK_ASSERT(inp);
1199 if ((inp->inp_vflag & INP_IPV6) != 0) {
1200 struct ip6_hdr *ip6;
1202 ip6 = (struct ip6_hdr *)ip_ptr;
1203 ip6->ip6_flow = (ip6->ip6_flow & ~IPV6_FLOWINFO_MASK) |
1204 (inp->inp_flow & IPV6_FLOWINFO_MASK);
1205 ip6->ip6_vfc = (ip6->ip6_vfc & ~IPV6_VERSION_MASK) |
1206 (IPV6_VERSION & IPV6_VERSION_MASK);
1207 ip6->ip6_nxt = IPPROTO_TCP;
1208 ip6->ip6_plen = htons(sizeof(struct tcphdr));
1209 ip6->ip6_src = inp->in6p_laddr;
1210 ip6->ip6_dst = inp->in6p_faddr;
1213 #if defined(INET6) && defined(INET)
1220 ip = (struct ip *)ip_ptr;
1221 ip->ip_v = IPVERSION;
1223 ip->ip_tos = inp->inp_ip_tos;
1227 ip->ip_ttl = inp->inp_ip_ttl;
1229 ip->ip_p = IPPROTO_TCP;
1230 ip->ip_src = inp->inp_laddr;
1231 ip->ip_dst = inp->inp_faddr;
1234 th->th_sport = inp->inp_lport;
1235 th->th_dport = inp->inp_fport;
1243 th->th_sum = 0; /* in_pseudo() is called later for ipv4 */
1247 * Create template to be used to send tcp packets on a connection.
1248 * Allocates an mbuf and fills in a skeletal tcp/ip header. The only
1249 * use for this function is in keepalives, which use tcp_respond.
1252 tcpip_maketemplate(struct inpcb *inp)
1256 t = malloc(sizeof(*t), M_TEMP, M_NOWAIT);
1259 tcpip_fillheaders(inp, (void *)&t->tt_ipgen, (void *)&t->tt_t);
1264 * Send a single message to the TCP at address specified by
1265 * the given TCP/IP header. If m == NULL, then we make a copy
1266 * of the tcpiphdr at th and send directly to the addressed host.
1267 * This is used to force keep alive messages out using the TCP
1268 * template for a connection. If flags are given then we send
1269 * a message back to the TCP which originated the segment th,
1270 * and discard the mbuf containing it and any other attached mbufs.
1272 * In any case the ack and sequence number of the transmitted
1273 * segment are as specified by the parameters.
1275 * NOTE: If m != NULL, then th must point to *inside* the mbuf.
1278 tcp_respond(struct tcpcb *tp, void *ipgen, struct tcphdr *th, struct mbuf *m,
1279 tcp_seq ack, tcp_seq seq, int flags)
1288 struct ip6_hdr *ip6;
1291 int optlen, tlen, win;
1294 KASSERT(tp != NULL || m != NULL, ("tcp_respond: tp and m both NULL"));
1297 isipv6 = ((struct ip *)ipgen)->ip_v == (IPV6_VERSION >> 4);
1304 KASSERT(inp != NULL, ("tcp control block w/o inpcb"));
1305 INP_WLOCK_ASSERT(inp);
1312 if (!(flags & TH_RST)) {
1313 win = sbspace(&inp->inp_socket->so_rcv);
1314 if (win > TCP_MAXWIN << tp->rcv_scale)
1315 win = TCP_MAXWIN << tp->rcv_scale;
1317 if ((tp->t_flags & TF_NOOPT) == 0)
1321 m = m_gethdr(M_NOWAIT, MT_DATA);
1324 m->m_data += max_linkhdr;
1327 bcopy((caddr_t)ip6, mtod(m, caddr_t),
1328 sizeof(struct ip6_hdr));
1329 ip6 = mtod(m, struct ip6_hdr *);
1330 nth = (struct tcphdr *)(ip6 + 1);
1334 bcopy((caddr_t)ip, mtod(m, caddr_t), sizeof(struct ip));
1335 ip = mtod(m, struct ip *);
1336 nth = (struct tcphdr *)(ip + 1);
1338 bcopy((caddr_t)th, (caddr_t)nth, sizeof(struct tcphdr));
1340 } else if (!M_WRITABLE(m)) {
1343 /* Can't reuse 'm', allocate a new mbuf. */
1344 n = m_gethdr(M_NOWAIT, MT_DATA);
1350 if (!m_dup_pkthdr(n, m, M_NOWAIT)) {
1356 n->m_data += max_linkhdr;
1357 /* m_len is set later */
1358 #define xchg(a,b,type) { type t; t=a; a=b; b=t; }
1361 bcopy((caddr_t)ip6, mtod(n, caddr_t),
1362 sizeof(struct ip6_hdr));
1363 ip6 = mtod(n, struct ip6_hdr *);
1364 xchg(ip6->ip6_dst, ip6->ip6_src, struct in6_addr);
1365 nth = (struct tcphdr *)(ip6 + 1);
1369 bcopy((caddr_t)ip, mtod(n, caddr_t), sizeof(struct ip));
1370 ip = mtod(n, struct ip *);
1371 xchg(ip->ip_dst.s_addr, ip->ip_src.s_addr, uint32_t);
1372 nth = (struct tcphdr *)(ip + 1);
1374 bcopy((caddr_t)th, (caddr_t)nth, sizeof(struct tcphdr));
1375 xchg(nth->th_dport, nth->th_sport, uint16_t);
1382 * XXX MRT We inherit the FIB, which is lucky.
1386 m->m_data = (caddr_t)ipgen;
1387 /* m_len is set later */
1390 xchg(ip6->ip6_dst, ip6->ip6_src, struct in6_addr);
1391 nth = (struct tcphdr *)(ip6 + 1);
1395 xchg(ip->ip_dst.s_addr, ip->ip_src.s_addr, uint32_t);
1396 nth = (struct tcphdr *)(ip + 1);
1400 * this is usually a case when an extension header
1401 * exists between the IPv6 header and the
1404 nth->th_sport = th->th_sport;
1405 nth->th_dport = th->th_dport;
1407 xchg(nth->th_dport, nth->th_sport, uint16_t);
1413 tlen = sizeof (struct ip6_hdr) + sizeof (struct tcphdr);
1415 #if defined(INET) && defined(INET6)
1419 tlen = sizeof (struct tcpiphdr);
1423 KASSERT(M_TRAILINGSPACE(m) >= tlen,
1424 ("Not enough trailing space for message (m=%p, need=%d, have=%ld)",
1425 m, tlen, (long)M_TRAILINGSPACE(m)));
1430 /* Make sure we have room. */
1431 if (M_TRAILINGSPACE(m) < TCP_MAXOLEN) {
1432 m->m_next = m_get(M_NOWAIT, MT_DATA);
1434 optp = mtod(m->m_next, u_char *);
1439 optp = (u_char *) (nth + 1);
1445 if (tp->t_flags & TF_RCVD_TSTMP) {
1446 to.to_tsval = tcp_ts_getticks() + tp->ts_offset;
1447 to.to_tsecr = tp->ts_recent;
1448 to.to_flags |= TOF_TS;
1450 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE)
1451 /* TCP-MD5 (RFC2385). */
1452 if (tp->t_flags & TF_SIGNATURE)
1453 to.to_flags |= TOF_SIGNATURE;
1455 /* Add the options. */
1456 tlen += optlen = tcp_addoptions(&to, optp);
1458 /* Update m_len in the correct mbuf. */
1459 optm->m_len += optlen;
1465 ip6->ip6_vfc = IPV6_VERSION;
1466 ip6->ip6_nxt = IPPROTO_TCP;
1467 ip6->ip6_plen = htons(tlen - sizeof(*ip6));
1470 #if defined(INET) && defined(INET6)
1475 ip->ip_len = htons(tlen);
1476 ip->ip_ttl = V_ip_defttl;
1477 if (V_path_mtu_discovery)
1478 ip->ip_off |= htons(IP_DF);
1481 m->m_pkthdr.len = tlen;
1482 m->m_pkthdr.rcvif = NULL;
1486 * Packet is associated with a socket, so allow the
1487 * label of the response to reflect the socket label.
1489 INP_WLOCK_ASSERT(inp);
1490 mac_inpcb_create_mbuf(inp, m);
1493 * Packet is not associated with a socket, so possibly
1494 * update the label in place.
1496 mac_netinet_tcp_reply(m);
1499 nth->th_seq = htonl(seq);
1500 nth->th_ack = htonl(ack);
1502 nth->th_off = (sizeof (struct tcphdr) + optlen) >> 2;
1503 nth->th_flags = flags;
1505 nth->th_win = htons((u_short) (win >> tp->rcv_scale));
1507 nth->th_win = htons((u_short)win);
1510 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE)
1511 if (to.to_flags & TOF_SIGNATURE) {
1512 if (!TCPMD5_ENABLED() ||
1513 TCPMD5_OUTPUT(m, nth, to.to_signature) != 0) {
1520 m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum);
1523 m->m_pkthdr.csum_flags = CSUM_TCP_IPV6;
1524 nth->th_sum = in6_cksum_pseudo(ip6,
1525 tlen - sizeof(struct ip6_hdr), IPPROTO_TCP, 0);
1526 ip6->ip6_hlim = in6_selecthlim(tp != NULL ? tp->t_inpcb :
1530 #if defined(INET6) && defined(INET)
1535 m->m_pkthdr.csum_flags = CSUM_TCP;
1536 nth->th_sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr,
1537 htons((u_short)(tlen - sizeof(struct ip) + ip->ip_p)));
1541 if (tp == NULL || (inp->inp_socket->so_options & SO_DEBUG))
1542 tcp_trace(TA_OUTPUT, 0, tp, mtod(m, void *), th, 0);
1544 TCP_PROBE3(debug__output, tp, th, m);
1546 TCP_PROBE5(accept__refused, NULL, NULL, m, tp, nth);
1550 TCP_PROBE5(send, NULL, tp, ip6, tp, nth);
1551 (void)ip6_output(m, NULL, NULL, 0, NULL, NULL, inp);
1554 #if defined(INET) && defined(INET6)
1559 TCP_PROBE5(send, NULL, tp, ip, tp, nth);
1560 (void)ip_output(m, NULL, NULL, 0, NULL, inp);
1566 * Create a new TCP control block, making an
1567 * empty reassembly queue and hooking it to the argument
1568 * protocol control block. The `inp' parameter must have
1569 * come from the zone allocator set up in tcp_init().
1572 tcp_newtcpcb(struct inpcb *inp)
1574 struct tcpcb_mem *tm;
1577 int isipv6 = (inp->inp_vflag & INP_IPV6) != 0;
1580 tm = uma_zalloc(V_tcpcb_zone, M_NOWAIT | M_ZERO);
1585 /* Initialise cc_var struct for this tcpcb. */
1587 tp->ccv->type = IPPROTO_TCP;
1588 tp->ccv->ccvc.tcp = tp;
1589 rw_rlock(&tcp_function_lock);
1590 tp->t_fb = tcp_func_set_ptr;
1591 refcount_acquire(&tp->t_fb->tfb_refcnt);
1592 rw_runlock(&tcp_function_lock);
1594 * Use the current system default CC algorithm.
1597 KASSERT(!STAILQ_EMPTY(&cc_list), ("cc_list is empty!"));
1598 CC_ALGO(tp) = CC_DEFAULT();
1601 if (CC_ALGO(tp)->cb_init != NULL)
1602 if (CC_ALGO(tp)->cb_init(tp->ccv) > 0) {
1603 if (tp->t_fb->tfb_tcp_fb_fini)
1604 (*tp->t_fb->tfb_tcp_fb_fini)(tp, 1);
1605 refcount_release(&tp->t_fb->tfb_refcnt);
1606 uma_zfree(V_tcpcb_zone, tm);
1612 if (khelp_init_osd(HELPER_CLASS_TCP, tp->osd)) {
1613 if (tp->t_fb->tfb_tcp_fb_fini)
1614 (*tp->t_fb->tfb_tcp_fb_fini)(tp, 1);
1615 refcount_release(&tp->t_fb->tfb_refcnt);
1616 uma_zfree(V_tcpcb_zone, tm);
1622 tp->t_vnet = inp->inp_vnet;
1624 tp->t_timers = &tm->tt;
1625 /* LIST_INIT(&tp->t_segq); */ /* XXX covered by M_ZERO */
1628 isipv6 ? V_tcp_v6mssdflt :
1632 /* Set up our timeouts. */
1633 callout_init(&tp->t_timers->tt_rexmt, 1);
1634 callout_init(&tp->t_timers->tt_persist, 1);
1635 callout_init(&tp->t_timers->tt_keep, 1);
1636 callout_init(&tp->t_timers->tt_2msl, 1);
1637 callout_init(&tp->t_timers->tt_delack, 1);
1639 if (V_tcp_do_rfc1323)
1640 tp->t_flags = (TF_REQ_SCALE|TF_REQ_TSTMP);
1642 tp->t_flags |= TF_SACK_PERMIT;
1643 TAILQ_INIT(&tp->snd_holes);
1645 * The tcpcb will hold a reference on its inpcb until tcp_discardcb()
1648 in_pcbref(inp); /* Reference for tcpcb */
1652 * Init srtt to TCPTV_SRTTBASE (0), so we can tell that we have no
1653 * rtt estimate. Set rttvar so that srtt + 4 * rttvar gives
1654 * reasonable initial retransmit time.
1656 tp->t_srtt = TCPTV_SRTTBASE;
1657 tp->t_rttvar = ((TCPTV_RTOBASE - TCPTV_SRTTBASE) << TCP_RTTVAR_SHIFT) / 4;
1658 tp->t_rttmin = tcp_rexmit_min;
1659 tp->t_rxtcur = TCPTV_RTOBASE;
1660 tp->snd_cwnd = TCP_MAXWIN << TCP_MAX_WINSHIFT;
1661 tp->snd_ssthresh = TCP_MAXWIN << TCP_MAX_WINSHIFT;
1662 tp->t_rcvtime = ticks;
1664 * IPv4 TTL initialization is necessary for an IPv6 socket as well,
1665 * because the socket may be bound to an IPv6 wildcard address,
1666 * which may match an IPv4-mapped IPv6 address.
1668 inp->inp_ip_ttl = V_ip_defttl;
1672 * Init the TCP PCAP queues.
1674 tcp_pcap_tcpcb_init(tp);
1677 /* Initialize the per-TCPCB log data. */
1678 tcp_log_tcpcbinit(tp);
1680 if (tp->t_fb->tfb_tcp_fb_init) {
1681 (*tp->t_fb->tfb_tcp_fb_init)(tp);
1683 return (tp); /* XXX */
1687 * Switch the congestion control algorithm back to NewReno for any active
1688 * control blocks using an algorithm which is about to go away.
1689 * This ensures the CC framework can allow the unload to proceed without leaving
1690 * any dangling pointers which would trigger a panic.
1691 * Returning non-zero would inform the CC framework that something went wrong
1692 * and it would be unsafe to allow the unload to proceed. However, there is no
1693 * way for this to occur with this implementation so we always return zero.
1696 tcp_ccalgounload(struct cc_algo *unload_algo)
1698 struct cc_algo *tmpalgo;
1701 VNET_ITERATOR_DECL(vnet_iter);
1704 * Check all active control blocks across all network stacks and change
1705 * any that are using "unload_algo" back to NewReno. If "unload_algo"
1706 * requires cleanup code to be run, call it.
1709 VNET_FOREACH(vnet_iter) {
1710 CURVNET_SET(vnet_iter);
1711 INP_INFO_WLOCK(&V_tcbinfo);
1713 * New connections already part way through being initialised
1714 * with the CC algo we're removing will not race with this code
1715 * because the INP_INFO_WLOCK is held during initialisation. We
1716 * therefore don't enter the loop below until the connection
1717 * list has stabilised.
1719 LIST_FOREACH(inp, &V_tcb, inp_list) {
1721 /* Important to skip tcptw structs. */
1722 if (!(inp->inp_flags & INP_TIMEWAIT) &&
1723 (tp = intotcpcb(inp)) != NULL) {
1725 * By holding INP_WLOCK here, we are assured
1726 * that the connection is not currently
1727 * executing inside the CC module's functions
1728 * i.e. it is safe to make the switch back to
1731 if (CC_ALGO(tp) == unload_algo) {
1732 tmpalgo = CC_ALGO(tp);
1733 /* NewReno does not require any init. */
1734 CC_ALGO(tp) = &newreno_cc_algo;
1735 if (tmpalgo->cb_destroy != NULL)
1736 tmpalgo->cb_destroy(tp->ccv);
1741 INP_INFO_WUNLOCK(&V_tcbinfo);
1744 VNET_LIST_RUNLOCK();
1750 * Drop a TCP connection, reporting
1751 * the specified error. If connection is synchronized,
1752 * then send a RST to peer.
1755 tcp_drop(struct tcpcb *tp, int errno)
1757 struct socket *so = tp->t_inpcb->inp_socket;
1759 INP_INFO_LOCK_ASSERT(&V_tcbinfo);
1760 INP_WLOCK_ASSERT(tp->t_inpcb);
1762 if (TCPS_HAVERCVDSYN(tp->t_state)) {
1763 tcp_state_change(tp, TCPS_CLOSED);
1764 (void) tp->t_fb->tfb_tcp_output(tp);
1765 TCPSTAT_INC(tcps_drops);
1767 TCPSTAT_INC(tcps_conndrops);
1768 if (errno == ETIMEDOUT && tp->t_softerror)
1769 errno = tp->t_softerror;
1770 so->so_error = errno;
1771 return (tcp_close(tp));
1775 tcp_discardcb(struct tcpcb *tp)
1777 struct inpcb *inp = tp->t_inpcb;
1778 struct socket *so = inp->inp_socket;
1780 int isipv6 = (inp->inp_vflag & INP_IPV6) != 0;
1784 INP_WLOCK_ASSERT(inp);
1787 * Make sure that all of our timers are stopped before we delete the
1790 * If stopping a timer fails, we schedule a discard function in same
1791 * callout, and the last discard function called will take care of
1792 * deleting the tcpcb.
1794 tp->t_timers->tt_draincnt = 0;
1795 tcp_timer_stop(tp, TT_REXMT);
1796 tcp_timer_stop(tp, TT_PERSIST);
1797 tcp_timer_stop(tp, TT_KEEP);
1798 tcp_timer_stop(tp, TT_2MSL);
1799 tcp_timer_stop(tp, TT_DELACK);
1800 if (tp->t_fb->tfb_tcp_timer_stop_all) {
1802 * Call the stop-all function of the methods,
1803 * this function should call the tcp_timer_stop()
1804 * method with each of the function specific timeouts.
1805 * That stop will be called via the tfb_tcp_timer_stop()
1806 * which should use the async drain function of the
1807 * callout system (see tcp_var.h).
1809 tp->t_fb->tfb_tcp_timer_stop_all(tp);
1813 * If we got enough samples through the srtt filter,
1814 * save the rtt and rttvar in the routing entry.
1815 * 'Enough' is arbitrarily defined as 4 rtt samples.
1816 * 4 samples is enough for the srtt filter to converge
1817 * to within enough % of the correct value; fewer samples
1818 * and we could save a bogus rtt. The danger is not high
1819 * as tcp quickly recovers from everything.
1820 * XXX: Works very well but needs some more statistics!
1822 if (tp->t_rttupdated >= 4) {
1823 struct hc_metrics_lite metrics;
1826 bzero(&metrics, sizeof(metrics));
1828 * Update the ssthresh always when the conditions below
1829 * are satisfied. This gives us better new start value
1830 * for the congestion avoidance for new connections.
1831 * ssthresh is only set if packet loss occurred on a session.
1833 * XXXRW: 'so' may be NULL here, and/or socket buffer may be
1834 * being torn down. Ideally this code would not use 'so'.
1836 ssthresh = tp->snd_ssthresh;
1837 if (ssthresh != 0 && ssthresh < so->so_snd.sb_hiwat / 2) {
1839 * convert the limit from user data bytes to
1840 * packets then to packet data bytes.
1842 ssthresh = (ssthresh + tp->t_maxseg / 2) / tp->t_maxseg;
1845 ssthresh *= (tp->t_maxseg +
1847 (isipv6 ? sizeof (struct ip6_hdr) +
1848 sizeof (struct tcphdr) :
1850 sizeof (struct tcpiphdr)
1857 metrics.rmx_ssthresh = ssthresh;
1859 metrics.rmx_rtt = tp->t_srtt;
1860 metrics.rmx_rttvar = tp->t_rttvar;
1861 metrics.rmx_cwnd = tp->snd_cwnd;
1862 metrics.rmx_sendpipe = 0;
1863 metrics.rmx_recvpipe = 0;
1865 tcp_hc_update(&inp->inp_inc, &metrics);
1868 /* free the reassembly queue, if any */
1869 tcp_reass_flush(tp);
1872 /* Disconnect offload device, if any. */
1873 if (tp->t_flags & TF_TOE)
1874 tcp_offload_detach(tp);
1877 tcp_free_sackholes(tp);
1880 /* Free the TCP PCAP queues. */
1881 tcp_pcap_drain(&(tp->t_inpkts));
1882 tcp_pcap_drain(&(tp->t_outpkts));
1885 /* Allow the CC algorithm to clean up after itself. */
1886 if (CC_ALGO(tp)->cb_destroy != NULL)
1887 CC_ALGO(tp)->cb_destroy(tp->ccv);
1890 khelp_destroy_osd(tp->osd);
1894 inp->inp_ppcb = NULL;
1895 if (tp->t_timers->tt_draincnt == 0) {
1896 /* We own the last reference on tcpcb, let's free it. */
1898 tcp_log_tcpcbfini(tp);
1900 TCPSTATES_DEC(tp->t_state);
1901 if (tp->t_fb->tfb_tcp_fb_fini)
1902 (*tp->t_fb->tfb_tcp_fb_fini)(tp, 1);
1903 refcount_release(&tp->t_fb->tfb_refcnt);
1905 uma_zfree(V_tcpcb_zone, tp);
1906 released = in_pcbrele_wlocked(inp);
1907 KASSERT(!released, ("%s: inp %p should not have been released "
1908 "here", __func__, inp));
1913 tcp_timer_discard(void *ptp)
1918 tp = (struct tcpcb *)ptp;
1919 CURVNET_SET(tp->t_vnet);
1920 INP_INFO_RLOCK(&V_tcbinfo);
1922 KASSERT(inp != NULL, ("%s: tp %p tp->t_inpcb == NULL",
1925 KASSERT((tp->t_timers->tt_flags & TT_STOPPED) != 0,
1926 ("%s: tcpcb has to be stopped here", __func__));
1927 tp->t_timers->tt_draincnt--;
1928 if (tp->t_timers->tt_draincnt == 0) {
1929 /* We own the last reference on this tcpcb, let's free it. */
1931 tcp_log_tcpcbfini(tp);
1933 TCPSTATES_DEC(tp->t_state);
1934 if (tp->t_fb->tfb_tcp_fb_fini)
1935 (*tp->t_fb->tfb_tcp_fb_fini)(tp, 1);
1936 refcount_release(&tp->t_fb->tfb_refcnt);
1938 uma_zfree(V_tcpcb_zone, tp);
1939 if (in_pcbrele_wlocked(inp)) {
1940 INP_INFO_RUNLOCK(&V_tcbinfo);
1946 INP_INFO_RUNLOCK(&V_tcbinfo);
1951 * Attempt to close a TCP control block, marking it as dropped, and freeing
1952 * the socket if we hold the only reference.
1955 tcp_close(struct tcpcb *tp)
1957 struct inpcb *inp = tp->t_inpcb;
1960 INP_INFO_LOCK_ASSERT(&V_tcbinfo);
1961 INP_WLOCK_ASSERT(inp);
1964 if (tp->t_state == TCPS_LISTEN)
1965 tcp_offload_listen_stop(tp);
1968 * This releases the TFO pending counter resource for TFO listen
1969 * sockets as well as passively-created TFO sockets that transition
1970 * from SYN_RECEIVED to CLOSED.
1972 if (tp->t_tfo_pending) {
1973 tcp_fastopen_decrement_counter(tp->t_tfo_pending);
1974 tp->t_tfo_pending = NULL;
1977 TCPSTAT_INC(tcps_closed);
1978 if (tp->t_state != TCPS_CLOSED)
1979 tcp_state_change(tp, TCPS_CLOSED);
1980 KASSERT(inp->inp_socket != NULL, ("tcp_close: inp_socket NULL"));
1981 so = inp->inp_socket;
1982 soisdisconnected(so);
1983 if (inp->inp_flags & INP_SOCKREF) {
1984 KASSERT(so->so_state & SS_PROTOREF,
1985 ("tcp_close: !SS_PROTOREF"));
1986 inp->inp_flags &= ~INP_SOCKREF;
1989 so->so_state &= ~SS_PROTOREF;
1999 VNET_ITERATOR_DECL(vnet_iter);
2004 VNET_LIST_RLOCK_NOSLEEP();
2005 VNET_FOREACH(vnet_iter) {
2006 CURVNET_SET(vnet_iter);
2011 * Walk the tcpbs, if existing, and flush the reassembly queue,
2012 * if there is one...
2013 * XXX: The "Net/3" implementation doesn't imply that the TCP
2014 * reassembly queue should be flushed, but in a situation
2015 * where we're really low on mbufs, this is potentially
2018 INP_INFO_WLOCK(&V_tcbinfo);
2019 LIST_FOREACH(inpb, V_tcbinfo.ipi_listhead, inp_list) {
2020 if (inpb->inp_flags & INP_TIMEWAIT)
2023 if ((tcpb = intotcpcb(inpb)) != NULL) {
2024 tcp_reass_flush(tcpb);
2025 tcp_clean_sackreport(tcpb);
2027 tcp_log_drain(tcpb);
2030 if (tcp_pcap_aggressive_free) {
2031 /* Free the TCP PCAP queues. */
2032 tcp_pcap_drain(&(tcpb->t_inpkts));
2033 tcp_pcap_drain(&(tcpb->t_outpkts));
2039 INP_INFO_WUNLOCK(&V_tcbinfo);
2042 VNET_LIST_RUNLOCK_NOSLEEP();
2046 * Notify a tcp user of an asynchronous error;
2047 * store error as soft error, but wake up user
2048 * (for now, won't do anything until can select for soft error).
2050 * Do not wake up user since there currently is no mechanism for
2051 * reporting soft errors (yet - a kqueue filter may be added).
2053 static struct inpcb *
2054 tcp_notify(struct inpcb *inp, int error)
2058 INP_INFO_LOCK_ASSERT(&V_tcbinfo);
2059 INP_WLOCK_ASSERT(inp);
2061 if ((inp->inp_flags & INP_TIMEWAIT) ||
2062 (inp->inp_flags & INP_DROPPED))
2065 tp = intotcpcb(inp);
2066 KASSERT(tp != NULL, ("tcp_notify: tp == NULL"));
2069 * Ignore some errors if we are hooked up.
2070 * If connection hasn't completed, has retransmitted several times,
2071 * and receives a second error, give up now. This is better
2072 * than waiting a long time to establish a connection that
2073 * can never complete.
2075 if (tp->t_state == TCPS_ESTABLISHED &&
2076 (error == EHOSTUNREACH || error == ENETUNREACH ||
2077 error == EHOSTDOWN)) {
2078 if (inp->inp_route.ro_rt) {
2079 RTFREE(inp->inp_route.ro_rt);
2080 inp->inp_route.ro_rt = (struct rtentry *)NULL;
2083 } else if (tp->t_state < TCPS_ESTABLISHED && tp->t_rxtshift > 3 &&
2085 tp = tcp_drop(tp, error);
2091 tp->t_softerror = error;
2095 wakeup( &so->so_timeo);
2102 tcp_pcblist(SYSCTL_HANDLER_ARGS)
2104 int error, i, m, n, pcb_count;
2105 struct inpcb *inp, **inp_list;
2110 * The process of preparing the TCB list is too time-consuming and
2111 * resource-intensive to repeat twice on every request.
2113 if (req->oldptr == NULL) {
2114 n = V_tcbinfo.ipi_count +
2115 counter_u64_fetch(V_tcps_states[TCPS_SYN_RECEIVED]);
2116 n += imax(n / 8, 10);
2117 req->oldidx = 2 * (sizeof xig) + n * sizeof(struct xtcpcb);
2121 if (req->newptr != NULL)
2125 * OK, now we're committed to doing something.
2127 INP_LIST_RLOCK(&V_tcbinfo);
2128 gencnt = V_tcbinfo.ipi_gencnt;
2129 n = V_tcbinfo.ipi_count;
2130 INP_LIST_RUNLOCK(&V_tcbinfo);
2132 m = counter_u64_fetch(V_tcps_states[TCPS_SYN_RECEIVED]);
2134 error = sysctl_wire_old_buffer(req, 2 * (sizeof xig)
2135 + (n + m) * sizeof(struct xtcpcb));
2139 xig.xig_len = sizeof xig;
2140 xig.xig_count = n + m;
2141 xig.xig_gen = gencnt;
2142 xig.xig_sogen = so_gencnt;
2143 error = SYSCTL_OUT(req, &xig, sizeof xig);
2147 error = syncache_pcblist(req, m, &pcb_count);
2151 inp_list = malloc(n * sizeof *inp_list, M_TEMP, M_WAITOK);
2153 INP_INFO_WLOCK(&V_tcbinfo);
2154 for (inp = LIST_FIRST(V_tcbinfo.ipi_listhead), i = 0;
2155 inp != NULL && i < n; inp = LIST_NEXT(inp, inp_list)) {
2157 if (inp->inp_gencnt <= gencnt) {
2159 * XXX: This use of cr_cansee(), introduced with
2160 * TCP state changes, is not quite right, but for
2161 * now, better than nothing.
2163 if (inp->inp_flags & INP_TIMEWAIT) {
2164 if (intotw(inp) != NULL)
2165 error = cr_cansee(req->td->td_ucred,
2166 intotw(inp)->tw_cred);
2168 error = EINVAL; /* Skip this inp. */
2170 error = cr_canseeinpcb(req->td->td_ucred, inp);
2173 inp_list[i++] = inp;
2178 INP_INFO_WUNLOCK(&V_tcbinfo);
2182 for (i = 0; i < n; i++) {
2185 if (inp->inp_gencnt <= gencnt) {
2188 tcp_inptoxtp(inp, &xt);
2190 error = SYSCTL_OUT(req, &xt, sizeof xt);
2194 INP_INFO_RLOCK(&V_tcbinfo);
2195 for (i = 0; i < n; i++) {
2198 if (!in_pcbrele_rlocked(inp))
2201 INP_INFO_RUNLOCK(&V_tcbinfo);
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);
2218 free(inp_list, M_TEMP);
2222 SYSCTL_PROC(_net_inet_tcp, TCPCTL_PCBLIST, pcblist,
2223 CTLTYPE_OPAQUE | CTLFLAG_RD, NULL, 0,
2224 tcp_pcblist, "S,xtcpcb", "List of active TCP connections");
2228 tcp_getcred(SYSCTL_HANDLER_ARGS)
2231 struct sockaddr_in addrs[2];
2235 error = priv_check(req->td, PRIV_NETINET_GETCRED);
2238 error = SYSCTL_IN(req, addrs, sizeof(addrs));
2241 inp = in_pcblookup(&V_tcbinfo, addrs[1].sin_addr, addrs[1].sin_port,
2242 addrs[0].sin_addr, addrs[0].sin_port, INPLOOKUP_RLOCKPCB, NULL);
2244 if (inp->inp_socket == NULL)
2247 error = cr_canseeinpcb(req->td->td_ucred, inp);
2249 cru2x(inp->inp_cred, &xuc);
2254 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred));
2258 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, getcred,
2259 CTLTYPE_OPAQUE|CTLFLAG_RW|CTLFLAG_PRISON, 0, 0,
2260 tcp_getcred, "S,xucred", "Get the xucred of a TCP connection");
2265 tcp6_getcred(SYSCTL_HANDLER_ARGS)
2268 struct sockaddr_in6 addrs[2];
2275 error = priv_check(req->td, PRIV_NETINET_GETCRED);
2278 error = SYSCTL_IN(req, addrs, sizeof(addrs));
2281 if ((error = sa6_embedscope(&addrs[0], V_ip6_use_defzone)) != 0 ||
2282 (error = sa6_embedscope(&addrs[1], V_ip6_use_defzone)) != 0) {
2285 if (IN6_IS_ADDR_V4MAPPED(&addrs[0].sin6_addr)) {
2287 if (IN6_IS_ADDR_V4MAPPED(&addrs[1].sin6_addr))
2296 inp = in_pcblookup(&V_tcbinfo,
2297 *(struct in_addr *)&addrs[1].sin6_addr.s6_addr[12],
2299 *(struct in_addr *)&addrs[0].sin6_addr.s6_addr[12],
2300 addrs[0].sin6_port, INPLOOKUP_RLOCKPCB, NULL);
2303 inp = in6_pcblookup(&V_tcbinfo,
2304 &addrs[1].sin6_addr, addrs[1].sin6_port,
2305 &addrs[0].sin6_addr, addrs[0].sin6_port,
2306 INPLOOKUP_RLOCKPCB, NULL);
2308 if (inp->inp_socket == NULL)
2311 error = cr_canseeinpcb(req->td->td_ucred, inp);
2313 cru2x(inp->inp_cred, &xuc);
2318 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred));
2322 SYSCTL_PROC(_net_inet6_tcp6, OID_AUTO, getcred,
2323 CTLTYPE_OPAQUE|CTLFLAG_RW|CTLFLAG_PRISON, 0, 0,
2324 tcp6_getcred, "S,xucred", "Get the xucred of a TCP6 connection");
2330 tcp_ctlinput(int cmd, struct sockaddr *sa, void *vip)
2332 struct ip *ip = vip;
2334 struct in_addr faddr;
2337 struct inpcb *(*notify)(struct inpcb *, int) = tcp_notify;
2339 struct in_conninfo inc;
2340 tcp_seq icmp_tcp_seq;
2343 faddr = ((struct sockaddr_in *)sa)->sin_addr;
2344 if (sa->sa_family != AF_INET || faddr.s_addr == INADDR_ANY)
2347 if (cmd == PRC_MSGSIZE)
2348 notify = tcp_mtudisc_notify;
2349 else if (V_icmp_may_rst && (cmd == PRC_UNREACH_ADMIN_PROHIB ||
2350 cmd == PRC_UNREACH_PORT || cmd == PRC_UNREACH_PROTOCOL ||
2351 cmd == PRC_TIMXCEED_INTRANS) && ip)
2352 notify = tcp_drop_syn_sent;
2355 * Hostdead is ugly because it goes linearly through all PCBs.
2356 * XXX: We never get this from ICMP, otherwise it makes an
2357 * excellent DoS attack on machines with many connections.
2359 else if (cmd == PRC_HOSTDEAD)
2361 else if ((unsigned)cmd >= PRC_NCMDS || inetctlerrmap[cmd] == 0)
2365 in_pcbnotifyall(&V_tcbinfo, faddr, inetctlerrmap[cmd], notify);
2369 icp = (struct icmp *)((caddr_t)ip - offsetof(struct icmp, icmp_ip));
2370 th = (struct tcphdr *)((caddr_t)ip + (ip->ip_hl << 2));
2371 INP_INFO_RLOCK(&V_tcbinfo);
2372 inp = in_pcblookup(&V_tcbinfo, faddr, th->th_dport, ip->ip_src,
2373 th->th_sport, INPLOOKUP_WLOCKPCB, NULL);
2374 if (inp != NULL && PRC_IS_REDIRECT(cmd)) {
2375 /* signal EHOSTDOWN, as it flushes the cached route */
2376 inp = (*notify)(inp, EHOSTDOWN);
2379 icmp_tcp_seq = th->th_seq;
2381 if (!(inp->inp_flags & INP_TIMEWAIT) &&
2382 !(inp->inp_flags & INP_DROPPED) &&
2383 !(inp->inp_socket == NULL)) {
2384 tp = intotcpcb(inp);
2385 if (SEQ_GEQ(ntohl(icmp_tcp_seq), tp->snd_una) &&
2386 SEQ_LT(ntohl(icmp_tcp_seq), tp->snd_max)) {
2387 if (cmd == PRC_MSGSIZE) {
2390 * If we got a needfrag set the MTU
2391 * in the route to the suggested new
2392 * value (if given) and then notify.
2394 mtu = ntohs(icp->icmp_nextmtu);
2396 * If no alternative MTU was
2397 * proposed, try the next smaller
2402 ntohs(ip->ip_len), 1);
2403 if (mtu < V_tcp_minmss +
2404 sizeof(struct tcpiphdr))
2405 mtu = V_tcp_minmss +
2406 sizeof(struct tcpiphdr);
2408 * Only process the offered MTU if it
2409 * is smaller than the current one.
2411 if (mtu < tp->t_maxseg +
2412 sizeof(struct tcpiphdr)) {
2413 bzero(&inc, sizeof(inc));
2414 inc.inc_faddr = faddr;
2416 inp->inp_inc.inc_fibnum;
2417 tcp_hc_updatemtu(&inc, mtu);
2418 tcp_mtudisc(inp, mtu);
2421 inp = (*notify)(inp,
2422 inetctlerrmap[cmd]);
2426 bzero(&inc, sizeof(inc));
2427 inc.inc_fport = th->th_dport;
2428 inc.inc_lport = th->th_sport;
2429 inc.inc_faddr = faddr;
2430 inc.inc_laddr = ip->ip_src;
2431 syncache_unreach(&inc, icmp_tcp_seq);
2436 INP_INFO_RUNLOCK(&V_tcbinfo);
2442 tcp6_ctlinput(int cmd, struct sockaddr *sa, void *d)
2444 struct in6_addr *dst;
2445 struct inpcb *(*notify)(struct inpcb *, int) = tcp_notify;
2446 struct ip6_hdr *ip6;
2450 struct icmp6_hdr *icmp6;
2451 struct ip6ctlparam *ip6cp = NULL;
2452 const struct sockaddr_in6 *sa6_src = NULL;
2453 struct in_conninfo inc;
2458 tcp_seq icmp_tcp_seq;
2462 if (sa->sa_family != AF_INET6 ||
2463 sa->sa_len != sizeof(struct sockaddr_in6))
2466 /* if the parameter is from icmp6, decode it. */
2468 ip6cp = (struct ip6ctlparam *)d;
2469 icmp6 = ip6cp->ip6c_icmp6;
2471 ip6 = ip6cp->ip6c_ip6;
2472 off = ip6cp->ip6c_off;
2473 sa6_src = ip6cp->ip6c_src;
2474 dst = ip6cp->ip6c_finaldst;
2478 off = 0; /* fool gcc */
2483 if (cmd == PRC_MSGSIZE)
2484 notify = tcp_mtudisc_notify;
2485 else if (V_icmp_may_rst && (cmd == PRC_UNREACH_ADMIN_PROHIB ||
2486 cmd == PRC_UNREACH_PORT || cmd == PRC_UNREACH_PROTOCOL ||
2487 cmd == PRC_TIMXCEED_INTRANS) && ip6 != NULL)
2488 notify = tcp_drop_syn_sent;
2491 * Hostdead is ugly because it goes linearly through all PCBs.
2492 * XXX: We never get this from ICMP, otherwise it makes an
2493 * excellent DoS attack on machines with many connections.
2495 else if (cmd == PRC_HOSTDEAD)
2497 else if ((unsigned)cmd >= PRC_NCMDS || inet6ctlerrmap[cmd] == 0)
2501 in6_pcbnotify(&V_tcbinfo, sa, 0,
2502 (const struct sockaddr *)sa6_src,
2503 0, cmd, NULL, notify);
2507 /* Check if we can safely get the ports from the tcp hdr */
2510 (int32_t) (off + sizeof(struct tcp_ports)))) {
2513 bzero(&t_ports, sizeof(struct tcp_ports));
2514 m_copydata(m, off, sizeof(struct tcp_ports), (caddr_t)&t_ports);
2515 INP_INFO_RLOCK(&V_tcbinfo);
2516 inp = in6_pcblookup(&V_tcbinfo, &ip6->ip6_dst, t_ports.th_dport,
2517 &ip6->ip6_src, t_ports.th_sport, INPLOOKUP_WLOCKPCB, NULL);
2518 if (inp != NULL && PRC_IS_REDIRECT(cmd)) {
2519 /* signal EHOSTDOWN, as it flushes the cached route */
2520 inp = (*notify)(inp, EHOSTDOWN);
2523 off += sizeof(struct tcp_ports);
2524 if (m->m_pkthdr.len < (int32_t) (off + sizeof(tcp_seq))) {
2527 m_copydata(m, off, sizeof(tcp_seq), (caddr_t)&icmp_tcp_seq);
2529 if (!(inp->inp_flags & INP_TIMEWAIT) &&
2530 !(inp->inp_flags & INP_DROPPED) &&
2531 !(inp->inp_socket == NULL)) {
2532 tp = intotcpcb(inp);
2533 if (SEQ_GEQ(ntohl(icmp_tcp_seq), tp->snd_una) &&
2534 SEQ_LT(ntohl(icmp_tcp_seq), tp->snd_max)) {
2535 if (cmd == PRC_MSGSIZE) {
2538 * If we got a needfrag set the MTU
2539 * in the route to the suggested new
2540 * value (if given) and then notify.
2542 mtu = ntohl(icmp6->icmp6_mtu);
2544 * If no alternative MTU was
2545 * proposed, or the proposed
2546 * MTU was too small, set to
2549 if (mtu < IPV6_MMTU)
2550 mtu = IPV6_MMTU - 8;
2551 bzero(&inc, sizeof(inc));
2552 inc.inc_fibnum = M_GETFIB(m);
2553 inc.inc_flags |= INC_ISIPV6;
2554 inc.inc6_faddr = *dst;
2555 if (in6_setscope(&inc.inc6_faddr,
2556 m->m_pkthdr.rcvif, NULL))
2559 * Only process the offered MTU if it
2560 * is smaller than the current one.
2562 if (mtu < tp->t_maxseg +
2563 sizeof (struct tcphdr) +
2564 sizeof (struct ip6_hdr)) {
2565 tcp_hc_updatemtu(&inc, mtu);
2566 tcp_mtudisc(inp, mtu);
2567 ICMP6STAT_INC(icp6s_pmtuchg);
2570 inp = (*notify)(inp,
2571 inet6ctlerrmap[cmd]);
2575 bzero(&inc, sizeof(inc));
2576 inc.inc_fibnum = M_GETFIB(m);
2577 inc.inc_flags |= INC_ISIPV6;
2578 inc.inc_fport = t_ports.th_dport;
2579 inc.inc_lport = t_ports.th_sport;
2580 inc.inc6_faddr = *dst;
2581 inc.inc6_laddr = ip6->ip6_src;
2582 syncache_unreach(&inc, icmp_tcp_seq);
2587 INP_INFO_RUNLOCK(&V_tcbinfo);
2593 * Following is where TCP initial sequence number generation occurs.
2595 * There are two places where we must use initial sequence numbers:
2596 * 1. In SYN-ACK packets.
2597 * 2. In SYN packets.
2599 * All ISNs for SYN-ACK packets are generated by the syncache. See
2600 * tcp_syncache.c for details.
2602 * The ISNs in SYN packets must be monotonic; TIME_WAIT recycling
2603 * depends on this property. In addition, these ISNs should be
2604 * unguessable so as to prevent connection hijacking. To satisfy
2605 * the requirements of this situation, the algorithm outlined in
2606 * RFC 1948 is used, with only small modifications.
2608 * Implementation details:
2610 * Time is based off the system timer, and is corrected so that it
2611 * increases by one megabyte per second. This allows for proper
2612 * recycling on high speed LANs while still leaving over an hour
2615 * As reading the *exact* system time is too expensive to be done
2616 * whenever setting up a TCP connection, we increment the time
2617 * offset in two ways. First, a small random positive increment
2618 * is added to isn_offset for each connection that is set up.
2619 * Second, the function tcp_isn_tick fires once per clock tick
2620 * and increments isn_offset as necessary so that sequence numbers
2621 * are incremented at approximately ISN_BYTES_PER_SECOND. The
2622 * random positive increments serve only to ensure that the same
2623 * exact sequence number is never sent out twice (as could otherwise
2624 * happen when a port is recycled in less than the system tick
2627 * net.inet.tcp.isn_reseed_interval controls the number of seconds
2628 * between seeding of isn_secret. This is normally set to zero,
2629 * as reseeding should not be necessary.
2631 * Locking of the global variables isn_secret, isn_last_reseed, isn_offset,
2632 * isn_offset_old, and isn_ctx is performed using the TCP pcbinfo lock. In
2633 * general, this means holding an exclusive (write) lock.
2636 #define ISN_BYTES_PER_SECOND 1048576
2637 #define ISN_STATIC_INCREMENT 4096
2638 #define ISN_RANDOM_INCREMENT (4096 - 1)
2640 static VNET_DEFINE(u_char, isn_secret[32]);
2641 static VNET_DEFINE(int, isn_last);
2642 static VNET_DEFINE(int, isn_last_reseed);
2643 static VNET_DEFINE(u_int32_t, isn_offset);
2644 static VNET_DEFINE(u_int32_t, isn_offset_old);
2646 #define V_isn_secret VNET(isn_secret)
2647 #define V_isn_last VNET(isn_last)
2648 #define V_isn_last_reseed VNET(isn_last_reseed)
2649 #define V_isn_offset VNET(isn_offset)
2650 #define V_isn_offset_old VNET(isn_offset_old)
2653 tcp_new_isn(struct tcpcb *tp)
2656 u_int32_t md5_buffer[4];
2658 u_int32_t projected_offset;
2660 INP_WLOCK_ASSERT(tp->t_inpcb);
2663 /* Seed if this is the first use, reseed if requested. */
2664 if ((V_isn_last_reseed == 0) || ((V_tcp_isn_reseed_interval > 0) &&
2665 (((u_int)V_isn_last_reseed + (u_int)V_tcp_isn_reseed_interval*hz)
2667 read_random(&V_isn_secret, sizeof(V_isn_secret));
2668 V_isn_last_reseed = ticks;
2671 /* Compute the md5 hash and return the ISN. */
2673 MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->inp_fport, sizeof(u_short));
2674 MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->inp_lport, sizeof(u_short));
2676 if ((tp->t_inpcb->inp_vflag & INP_IPV6) != 0) {
2677 MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->in6p_faddr,
2678 sizeof(struct in6_addr));
2679 MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->in6p_laddr,
2680 sizeof(struct in6_addr));
2684 MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->inp_faddr,
2685 sizeof(struct in_addr));
2686 MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->inp_laddr,
2687 sizeof(struct in_addr));
2689 MD5Update(&isn_ctx, (u_char *) &V_isn_secret, sizeof(V_isn_secret));
2690 MD5Final((u_char *) &md5_buffer, &isn_ctx);
2691 new_isn = (tcp_seq) md5_buffer[0];
2692 V_isn_offset += ISN_STATIC_INCREMENT +
2693 (arc4random() & ISN_RANDOM_INCREMENT);
2694 if (ticks != V_isn_last) {
2695 projected_offset = V_isn_offset_old +
2696 ISN_BYTES_PER_SECOND / hz * (ticks - V_isn_last);
2697 if (SEQ_GT(projected_offset, V_isn_offset))
2698 V_isn_offset = projected_offset;
2699 V_isn_offset_old = V_isn_offset;
2702 new_isn += V_isn_offset;
2708 * When a specific ICMP unreachable message is received and the
2709 * connection state is SYN-SENT, drop the connection. This behavior
2710 * is controlled by the icmp_may_rst sysctl.
2713 tcp_drop_syn_sent(struct inpcb *inp, int errno)
2717 INP_INFO_RLOCK_ASSERT(&V_tcbinfo);
2718 INP_WLOCK_ASSERT(inp);
2720 if ((inp->inp_flags & INP_TIMEWAIT) ||
2721 (inp->inp_flags & INP_DROPPED))
2724 tp = intotcpcb(inp);
2725 if (tp->t_state != TCPS_SYN_SENT)
2728 if (IS_FASTOPEN(tp->t_flags))
2729 tcp_fastopen_disable_path(tp);
2731 tp = tcp_drop(tp, errno);
2739 * When `need fragmentation' ICMP is received, update our idea of the MSS
2740 * based on the new value. Also nudge TCP to send something, since we
2741 * know the packet we just sent was dropped.
2742 * This duplicates some code in the tcp_mss() function in tcp_input.c.
2744 static struct inpcb *
2745 tcp_mtudisc_notify(struct inpcb *inp, int error)
2748 tcp_mtudisc(inp, -1);
2753 tcp_mtudisc(struct inpcb *inp, int mtuoffer)
2758 INP_WLOCK_ASSERT(inp);
2759 if ((inp->inp_flags & INP_TIMEWAIT) ||
2760 (inp->inp_flags & INP_DROPPED))
2763 tp = intotcpcb(inp);
2764 KASSERT(tp != NULL, ("tcp_mtudisc: tp == NULL"));
2766 tcp_mss_update(tp, -1, mtuoffer, NULL, NULL);
2768 so = inp->inp_socket;
2769 SOCKBUF_LOCK(&so->so_snd);
2770 /* If the mss is larger than the socket buffer, decrease the mss. */
2771 if (so->so_snd.sb_hiwat < tp->t_maxseg)
2772 tp->t_maxseg = so->so_snd.sb_hiwat;
2773 SOCKBUF_UNLOCK(&so->so_snd);
2775 TCPSTAT_INC(tcps_mturesent);
2777 tp->snd_nxt = tp->snd_una;
2778 tcp_free_sackholes(tp);
2779 tp->snd_recover = tp->snd_max;
2780 if (tp->t_flags & TF_SACK_PERMIT)
2781 EXIT_FASTRECOVERY(tp->t_flags);
2782 tp->t_fb->tfb_tcp_output(tp);
2787 * Look-up the routing entry to the peer of this inpcb. If no route
2788 * is found and it cannot be allocated, then return 0. This routine
2789 * is called by TCP routines that access the rmx structure and by
2790 * tcp_mss_update to get the peer/interface MTU.
2793 tcp_maxmtu(struct in_conninfo *inc, struct tcp_ifcap *cap)
2795 struct nhop4_extended nh4;
2797 uint32_t maxmtu = 0;
2799 KASSERT(inc != NULL, ("tcp_maxmtu with NULL in_conninfo pointer"));
2801 if (inc->inc_faddr.s_addr != INADDR_ANY) {
2803 if (fib4_lookup_nh_ext(inc->inc_fibnum, inc->inc_faddr,
2804 NHR_REF, 0, &nh4) != 0)
2808 maxmtu = nh4.nh_mtu;
2810 /* Report additional interface capabilities. */
2812 if (ifp->if_capenable & IFCAP_TSO4 &&
2813 ifp->if_hwassist & CSUM_TSO) {
2814 cap->ifcap |= CSUM_TSO;
2815 cap->tsomax = ifp->if_hw_tsomax;
2816 cap->tsomaxsegcount = ifp->if_hw_tsomaxsegcount;
2817 cap->tsomaxsegsize = ifp->if_hw_tsomaxsegsize;
2820 fib4_free_nh_ext(inc->inc_fibnum, &nh4);
2828 tcp_maxmtu6(struct in_conninfo *inc, struct tcp_ifcap *cap)
2830 struct nhop6_extended nh6;
2831 struct in6_addr dst6;
2834 uint32_t maxmtu = 0;
2836 KASSERT(inc != NULL, ("tcp_maxmtu6 with NULL in_conninfo pointer"));
2838 if (!IN6_IS_ADDR_UNSPECIFIED(&inc->inc6_faddr)) {
2839 in6_splitscope(&inc->inc6_faddr, &dst6, &scopeid);
2840 if (fib6_lookup_nh_ext(inc->inc_fibnum, &dst6, scopeid, 0,
2845 maxmtu = nh6.nh_mtu;
2847 /* Report additional interface capabilities. */
2849 if (ifp->if_capenable & IFCAP_TSO6 &&
2850 ifp->if_hwassist & CSUM_TSO) {
2851 cap->ifcap |= CSUM_TSO;
2852 cap->tsomax = ifp->if_hw_tsomax;
2853 cap->tsomaxsegcount = ifp->if_hw_tsomaxsegcount;
2854 cap->tsomaxsegsize = ifp->if_hw_tsomaxsegsize;
2857 fib6_free_nh_ext(inc->inc_fibnum, &nh6);
2865 * Calculate effective SMSS per RFC5681 definition for a given TCP
2866 * connection at its current state, taking into account SACK and etc.
2869 tcp_maxseg(const struct tcpcb *tp)
2873 if (tp->t_flags & TF_NOOPT)
2874 return (tp->t_maxseg);
2877 * Here we have a simplified code from tcp_addoptions(),
2878 * without a proper loop, and having most of paddings hardcoded.
2879 * We might make mistakes with padding here in some edge cases,
2880 * but this is harmless, since result of tcp_maxseg() is used
2881 * only in cwnd and ssthresh estimations.
2883 #define PAD(len) ((((len) / 4) + !!((len) % 4)) * 4)
2884 if (TCPS_HAVEESTABLISHED(tp->t_state)) {
2885 if (tp->t_flags & TF_RCVD_TSTMP)
2886 optlen = TCPOLEN_TSTAMP_APPA;
2889 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE)
2890 if (tp->t_flags & TF_SIGNATURE)
2891 optlen += PAD(TCPOLEN_SIGNATURE);
2893 if ((tp->t_flags & TF_SACK_PERMIT) && tp->rcv_numsacks > 0) {
2894 optlen += TCPOLEN_SACKHDR;
2895 optlen += tp->rcv_numsacks * TCPOLEN_SACK;
2896 optlen = PAD(optlen);
2899 if (tp->t_flags & TF_REQ_TSTMP)
2900 optlen = TCPOLEN_TSTAMP_APPA;
2902 optlen = PAD(TCPOLEN_MAXSEG);
2903 if (tp->t_flags & TF_REQ_SCALE)
2904 optlen += PAD(TCPOLEN_WINDOW);
2905 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE)
2906 if (tp->t_flags & TF_SIGNATURE)
2907 optlen += PAD(TCPOLEN_SIGNATURE);
2909 if (tp->t_flags & TF_SACK_PERMIT)
2910 optlen += PAD(TCPOLEN_SACK_PERMITTED);
2913 optlen = min(optlen, TCP_MAXOLEN);
2914 return (tp->t_maxseg - optlen);
2918 sysctl_drop(SYSCTL_HANDLER_ARGS)
2920 /* addrs[0] is a foreign socket, addrs[1] is a local one. */
2921 struct sockaddr_storage addrs[2];
2925 struct sockaddr_in *fin, *lin;
2927 struct sockaddr_in6 *fin6, *lin6;
2938 if (req->oldptr != NULL || req->oldlen != 0)
2940 if (req->newptr == NULL)
2942 if (req->newlen < sizeof(addrs))
2944 error = SYSCTL_IN(req, &addrs, sizeof(addrs));
2948 switch (addrs[0].ss_family) {
2951 fin6 = (struct sockaddr_in6 *)&addrs[0];
2952 lin6 = (struct sockaddr_in6 *)&addrs[1];
2953 if (fin6->sin6_len != sizeof(struct sockaddr_in6) ||
2954 lin6->sin6_len != sizeof(struct sockaddr_in6))
2956 if (IN6_IS_ADDR_V4MAPPED(&fin6->sin6_addr)) {
2957 if (!IN6_IS_ADDR_V4MAPPED(&lin6->sin6_addr))
2959 in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[0]);
2960 in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[1]);
2961 fin = (struct sockaddr_in *)&addrs[0];
2962 lin = (struct sockaddr_in *)&addrs[1];
2965 error = sa6_embedscope(fin6, V_ip6_use_defzone);
2968 error = sa6_embedscope(lin6, V_ip6_use_defzone);
2975 fin = (struct sockaddr_in *)&addrs[0];
2976 lin = (struct sockaddr_in *)&addrs[1];
2977 if (fin->sin_len != sizeof(struct sockaddr_in) ||
2978 lin->sin_len != sizeof(struct sockaddr_in))
2985 INP_INFO_RLOCK(&V_tcbinfo);
2986 switch (addrs[0].ss_family) {
2989 inp = in6_pcblookup(&V_tcbinfo, &fin6->sin6_addr,
2990 fin6->sin6_port, &lin6->sin6_addr, lin6->sin6_port,
2991 INPLOOKUP_WLOCKPCB, NULL);
2996 inp = in_pcblookup(&V_tcbinfo, fin->sin_addr, fin->sin_port,
2997 lin->sin_addr, lin->sin_port, INPLOOKUP_WLOCKPCB, NULL);
3002 if (inp->inp_flags & INP_TIMEWAIT) {
3004 * XXXRW: There currently exists a state where an
3005 * inpcb is present, but its timewait state has been
3006 * discarded. For now, don't allow dropping of this
3014 } else if (!(inp->inp_flags & INP_DROPPED) &&
3015 !(inp->inp_socket->so_options & SO_ACCEPTCONN)) {
3016 tp = intotcpcb(inp);
3017 tp = tcp_drop(tp, ECONNABORTED);
3024 INP_INFO_RUNLOCK(&V_tcbinfo);
3028 SYSCTL_PROC(_net_inet_tcp, TCPCTL_DROP, drop,
3029 CTLFLAG_VNET | CTLTYPE_STRUCT | CTLFLAG_WR | CTLFLAG_SKIP, NULL,
3030 0, sysctl_drop, "", "Drop TCP connection");
3033 * Generate a standardized TCP log line for use throughout the
3034 * tcp subsystem. Memory allocation is done with M_NOWAIT to
3035 * allow use in the interrupt context.
3037 * NB: The caller MUST free(s, M_TCPLOG) the returned string.
3038 * NB: The function may return NULL if memory allocation failed.
3040 * Due to header inclusion and ordering limitations the struct ip
3041 * and ip6_hdr pointers have to be passed as void pointers.
3044 tcp_log_vain(struct in_conninfo *inc, struct tcphdr *th, void *ip4hdr,
3048 /* Is logging enabled? */
3049 if (tcp_log_in_vain == 0)
3052 return (tcp_log_addr(inc, th, ip4hdr, ip6hdr));
3056 tcp_log_addrs(struct in_conninfo *inc, struct tcphdr *th, void *ip4hdr,
3060 /* Is logging enabled? */
3061 if (tcp_log_debug == 0)
3064 return (tcp_log_addr(inc, th, ip4hdr, ip6hdr));
3068 tcp_log_addr(struct in_conninfo *inc, struct tcphdr *th, void *ip4hdr,
3075 const struct ip6_hdr *ip6;
3077 ip6 = (const struct ip6_hdr *)ip6hdr;
3079 ip = (struct ip *)ip4hdr;
3082 * The log line looks like this:
3083 * "TCP: [1.2.3.4]:50332 to [1.2.3.4]:80 tcpflags 0x2<SYN>"
3085 size = sizeof("TCP: []:12345 to []:12345 tcpflags 0x2<>") +
3086 sizeof(PRINT_TH_FLAGS) + 1 +
3088 2 * INET6_ADDRSTRLEN;
3090 2 * INET_ADDRSTRLEN;
3093 s = malloc(size, M_TCPLOG, M_ZERO|M_NOWAIT);
3097 strcat(s, "TCP: [");
3100 if (inc && ((inc->inc_flags & INC_ISIPV6) == 0)) {
3101 inet_ntoa_r(inc->inc_faddr, sp);
3103 sprintf(sp, "]:%i to [", ntohs(inc->inc_fport));
3105 inet_ntoa_r(inc->inc_laddr, sp);
3107 sprintf(sp, "]:%i", ntohs(inc->inc_lport));
3110 ip6_sprintf(sp, &inc->inc6_faddr);
3112 sprintf(sp, "]:%i to [", ntohs(inc->inc_fport));
3114 ip6_sprintf(sp, &inc->inc6_laddr);
3116 sprintf(sp, "]:%i", ntohs(inc->inc_lport));
3117 } else if (ip6 && th) {
3118 ip6_sprintf(sp, &ip6->ip6_src);
3120 sprintf(sp, "]:%i to [", ntohs(th->th_sport));
3122 ip6_sprintf(sp, &ip6->ip6_dst);
3124 sprintf(sp, "]:%i", ntohs(th->th_dport));
3127 } else if (ip && th) {
3128 inet_ntoa_r(ip->ip_src, sp);
3130 sprintf(sp, "]:%i to [", ntohs(th->th_sport));
3132 inet_ntoa_r(ip->ip_dst, sp);
3134 sprintf(sp, "]:%i", ntohs(th->th_dport));
3142 sprintf(sp, " tcpflags 0x%b", th->th_flags, PRINT_TH_FLAGS);
3143 if (*(s + size - 1) != '\0')
3144 panic("%s: string too long", __func__);
3149 * A subroutine which makes it easy to track TCP state changes with DTrace.
3150 * This function shouldn't be called for t_state initializations that don't
3151 * correspond to actual TCP state transitions.
3154 tcp_state_change(struct tcpcb *tp, int newstate)
3156 #if defined(KDTRACE_HOOKS)
3157 int pstate = tp->t_state;
3160 TCPSTATES_DEC(tp->t_state);
3161 TCPSTATES_INC(newstate);
3162 tp->t_state = newstate;
3163 TCP_PROBE6(state__change, NULL, tp, NULL, tp, NULL, pstate);
3167 * Create an external-format (``xtcpcb'') structure using the information in
3168 * the kernel-format tcpcb structure pointed to by tp. This is done to
3169 * reduce the spew of irrelevant information over this interface, to isolate
3170 * user code from changes in the kernel structure, and potentially to provide
3171 * information-hiding if we decide that some of this information should be
3172 * hidden from users.
3175 tcp_inptoxtp(const struct inpcb *inp, struct xtcpcb *xt)
3177 struct tcpcb *tp = intotcpcb(inp);
3180 if (inp->inp_flags & INP_TIMEWAIT) {
3181 bzero(xt, sizeof(struct xtcpcb));
3182 xt->t_state = TCPS_TIME_WAIT;
3184 xt->t_state = tp->t_state;
3185 xt->t_logstate = tp->t_logstate;
3186 xt->t_flags = tp->t_flags;
3187 xt->t_sndzerowin = tp->t_sndzerowin;
3188 xt->t_sndrexmitpack = tp->t_sndrexmitpack;
3189 xt->t_rcvoopack = tp->t_rcvoopack;
3191 now = getsbinuptime();
3192 #define COPYTIMER(ttt) do { \
3193 if (callout_active(&tp->t_timers->ttt)) \
3194 xt->ttt = (tp->t_timers->ttt.c_time - now) / \
3199 COPYTIMER(tt_delack);
3200 COPYTIMER(tt_rexmt);
3201 COPYTIMER(tt_persist);
3205 xt->t_rcvtime = 1000 * (ticks - tp->t_rcvtime) / hz;
3207 bcopy(tp->t_fb->tfb_tcp_block_name, xt->xt_stack,
3208 TCP_FUNCTION_NAME_LEN_MAX);
3209 bzero(xt->xt_logid, TCP_LOG_ID_LEN);
3211 (void)tcp_log_get_id(tp, xt->xt_logid);
3215 xt->xt_len = sizeof(struct xtcpcb);
3216 in_pcbtoxinpcb(inp, &xt->xt_inp);
3217 if (inp->inp_socket == NULL)
3218 xt->xt_inp.xi_socket.xso_protocol = IPPROTO_TCP;