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cxgbe/t4_tom: Read the chip's DDP page sizes and save them in a
[freebsd-src.git] / sys / netinet / tcp_subr.c
bloba9cd81925daca2d21266cb4973ed3d8d0c108c3c
1 /*-
2 * Copyright (c) 1982, 1986, 1988, 1990, 1993, 1995
3 * The Regents of the University of California. All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 * 4. Neither the name of the University nor the names of its contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 *
29 * @(#)tcp_subr.c 8.2 (Berkeley) 5/24/95
30 */
31
32 #include <sys/cdefs.h>
33 __FBSDID("$FreeBSD$");
34
35 #include "opt_compat.h"
36 #include "opt_inet.h"
37 #include "opt_inet6.h"
38 #include "opt_ipsec.h"
39 #include "opt_tcpdebug.h"
40
41 #include <sys/param.h>
42 #include <sys/systm.h>
43 #include <sys/callout.h>
44 #include <sys/eventhandler.h>
45 #include <sys/hhook.h>
46 #include <sys/kernel.h>
47 #include <sys/khelp.h>
48 #include <sys/sysctl.h>
49 #include <sys/jail.h>
50 #include <sys/malloc.h>
51 #include <sys/refcount.h>
52 #include <sys/mbuf.h>
53 #ifdef INET6
54 #include <sys/domain.h>
55 #endif
56 #include <sys/priv.h>
57 #include <sys/proc.h>
58 #include <sys/sdt.h>
59 #include <sys/socket.h>
60 #include <sys/socketvar.h>
61 #include <sys/protosw.h>
62 #include <sys/random.h>
63
64 #include <vm/uma.h>
65
66 #include <net/route.h>
67 #include <net/if.h>
68 #include <net/if_var.h>
69 #include <net/vnet.h>
70
71 #include <netinet/in.h>
72 #include <netinet/in_fib.h>
73 #include <netinet/in_kdtrace.h>
74 #include <netinet/in_pcb.h>
75 #include <netinet/in_systm.h>
76 #include <netinet/in_var.h>
77 #include <netinet/ip.h>
78 #include <netinet/ip_icmp.h>
79 #include <netinet/ip_var.h>
80 #ifdef INET6
81 #include <netinet/icmp6.h>
82 #include <netinet/ip6.h>
83 #include <netinet6/in6_fib.h>
84 #include <netinet6/in6_pcb.h>
85 #include <netinet6/ip6_var.h>
86 #include <netinet6/scope6_var.h>
87 #include <netinet6/nd6.h>
88 #endif
89
90 #ifdef TCP_RFC7413
91 #include <netinet/tcp_fastopen.h>
92 #endif
93 #include <netinet/tcp.h>
94 #include <netinet/tcp_fsm.h>
95 #include <netinet/tcp_seq.h>
96 #include <netinet/tcp_timer.h>
97 #include <netinet/tcp_var.h>
98 #include <netinet/tcp_syncache.h>
99 #include <netinet/cc/cc.h>
100 #ifdef INET6
101 #include <netinet6/tcp6_var.h>
102 #endif
103 #include <netinet/tcpip.h>
104 #ifdef TCPPCAP
105 #include <netinet/tcp_pcap.h>
106 #endif
107 #ifdef TCPDEBUG
108 #include <netinet/tcp_debug.h>
109 #endif
110 #ifdef INET6
111 #include <netinet6/ip6protosw.h>
112 #endif
113 #ifdef TCP_OFFLOAD
114 #include <netinet/tcp_offload.h>
115 #endif
116
117 #ifdef IPSEC
118 #include <netipsec/ipsec.h>
119 #include <netipsec/xform.h>
120 #ifdef INET6
121 #include <netipsec/ipsec6.h>
122 #endif
123 #include <netipsec/key.h>
124 #include <sys/syslog.h>
125 #endif /*IPSEC*/
126
127 #include <machine/in_cksum.h>
128 #include <sys/md5.h>
129
130 #include <security/mac/mac_framework.h>
131
132 VNET_DEFINE(int, tcp_mssdflt) = TCP_MSS;
133 #ifdef INET6
134 VNET_DEFINE(int, tcp_v6mssdflt) = TCP6_MSS;
135 #endif
136
137 struct rwlock tcp_function_lock;
138
139 static int
140 sysctl_net_inet_tcp_mss_check(SYSCTL_HANDLER_ARGS)
141 {
142 int error, new;
143
144 new = V_tcp_mssdflt;
145 error = sysctl_handle_int(oidp, &new, 0, req);
146 if (error == 0 && req->newptr) {
147 if (new < TCP_MINMSS)
148 error = EINVAL;
149 else
150 V_tcp_mssdflt = new;
151 }
152 return (error);
153 }
154
155 SYSCTL_PROC(_net_inet_tcp, TCPCTL_MSSDFLT, mssdflt,
156 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW, &VNET_NAME(tcp_mssdflt), 0,
157 &sysctl_net_inet_tcp_mss_check, "I",
158 "Default TCP Maximum Segment Size");
159
160 #ifdef INET6
161 static int
162 sysctl_net_inet_tcp_mss_v6_check(SYSCTL_HANDLER_ARGS)
163 {
164 int error, new;
165
166 new = V_tcp_v6mssdflt;
167 error = sysctl_handle_int(oidp, &new, 0, req);
168 if (error == 0 && req->newptr) {
169 if (new < TCP_MINMSS)
170 error = EINVAL;
171 else
172 V_tcp_v6mssdflt = new;
173 }
174 return (error);
175 }
176
177 SYSCTL_PROC(_net_inet_tcp, TCPCTL_V6MSSDFLT, v6mssdflt,
178 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW, &VNET_NAME(tcp_v6mssdflt), 0,
179 &sysctl_net_inet_tcp_mss_v6_check, "I",
180 "Default TCP Maximum Segment Size for IPv6");
181 #endif /* INET6 */
182
183 /*
184 * Minimum MSS we accept and use. This prevents DoS attacks where
185 * we are forced to a ridiculous low MSS like 20 and send hundreds
186 * of packets instead of one. The effect scales with the available
187 * bandwidth and quickly saturates the CPU and network interface
188 * with packet generation and sending. Set to zero to disable MINMSS
189 * checking. This setting prevents us from sending too small packets.
190 */
191 VNET_DEFINE(int, tcp_minmss) = TCP_MINMSS;
192 SYSCTL_INT(_net_inet_tcp, OID_AUTO, minmss, CTLFLAG_VNET | CTLFLAG_RW,
193 &VNET_NAME(tcp_minmss), 0,
194 "Minimum TCP Maximum Segment Size");
195
196 VNET_DEFINE(int, tcp_do_rfc1323) = 1;
197 SYSCTL_INT(_net_inet_tcp, TCPCTL_DO_RFC1323, rfc1323, CTLFLAG_VNET | CTLFLAG_RW,
198 &VNET_NAME(tcp_do_rfc1323), 0,
199 "Enable rfc1323 (high performance TCP) extensions");
200
201 static int tcp_log_debug = 0;
202 SYSCTL_INT(_net_inet_tcp, OID_AUTO, log_debug, CTLFLAG_RW,
203 &tcp_log_debug, 0, "Log errors caused by incoming TCP segments");
204
205 static int tcp_tcbhashsize;
206 SYSCTL_INT(_net_inet_tcp, OID_AUTO, tcbhashsize, CTLFLAG_RDTUN | CTLFLAG_NOFETCH,
207 &tcp_tcbhashsize, 0, "Size of TCP control-block hashtable");
208
209 static int do_tcpdrain = 1;
210 SYSCTL_INT(_net_inet_tcp, OID_AUTO, do_tcpdrain, CTLFLAG_RW, &do_tcpdrain, 0,
211 "Enable tcp_drain routine for extra help when low on mbufs");
212
213 SYSCTL_UINT(_net_inet_tcp, OID_AUTO, pcbcount, CTLFLAG_VNET | CTLFLAG_RD,
214 &VNET_NAME(tcbinfo.ipi_count), 0, "Number of active PCBs");
215
216 static VNET_DEFINE(int, icmp_may_rst) = 1;
217 #define V_icmp_may_rst VNET(icmp_may_rst)
218 SYSCTL_INT(_net_inet_tcp, OID_AUTO, icmp_may_rst, CTLFLAG_VNET | CTLFLAG_RW,
219 &VNET_NAME(icmp_may_rst), 0,
220 "Certain ICMP unreachable messages may abort connections in SYN_SENT");
221
222 static VNET_DEFINE(int, tcp_isn_reseed_interval) = 0;
223 #define V_tcp_isn_reseed_interval VNET(tcp_isn_reseed_interval)
224 SYSCTL_INT(_net_inet_tcp, OID_AUTO, isn_reseed_interval, CTLFLAG_VNET | CTLFLAG_RW,
225 &VNET_NAME(tcp_isn_reseed_interval), 0,
226 "Seconds between reseeding of ISN secret");
227
228 static int tcp_soreceive_stream;
229 SYSCTL_INT(_net_inet_tcp, OID_AUTO, soreceive_stream, CTLFLAG_RDTUN,
230 &tcp_soreceive_stream, 0, "Using soreceive_stream for TCP sockets");
231
232 #ifdef TCP_SIGNATURE
233 static int tcp_sig_checksigs = 1;
234 SYSCTL_INT(_net_inet_tcp, OID_AUTO, signature_verify_input, CTLFLAG_RW,
235 &tcp_sig_checksigs, 0, "Verify RFC2385 digests on inbound traffic");
236 #endif
237
238 VNET_DEFINE(uma_zone_t, sack_hole_zone);
239 #define V_sack_hole_zone VNET(sack_hole_zone)
240
241 VNET_DEFINE(struct hhook_head *, tcp_hhh[HHOOK_TCP_LAST+1]);
242
243 static struct inpcb *tcp_notify(struct inpcb *, int);
244 static struct inpcb *tcp_mtudisc_notify(struct inpcb *, int);
245 static void tcp_mtudisc(struct inpcb *, int);
246 static char * tcp_log_addr(struct in_conninfo *inc, struct tcphdr *th,
247 void *ip4hdr, const void *ip6hdr);
248
249
250 static struct tcp_function_block tcp_def_funcblk = {
251 "default",
252 tcp_output,
253 tcp_do_segment,
254 tcp_default_ctloutput,
255 NULL,
256 NULL,
257 NULL,
258 NULL,
259 NULL,
260 NULL,
261 0,
262 0
263 };
264
265 int t_functions_inited = 0;
266 struct tcp_funchead t_functions;
267 static struct tcp_function_block *tcp_func_set_ptr = &tcp_def_funcblk;
268
269 static void
270 init_tcp_functions(void)
271 {
272 if (t_functions_inited == 0) {
273 TAILQ_INIT(&t_functions);
274 rw_init_flags(&tcp_function_lock, "tcp_func_lock" , 0);
275 t_functions_inited = 1;
276 }
277 }
278
279 static struct tcp_function_block *
280 find_tcp_functions_locked(struct tcp_function_set *fs)
281 {
282 struct tcp_function *f;
283 struct tcp_function_block *blk=NULL;
284
285 TAILQ_FOREACH(f, &t_functions, tf_next) {
286 if (strcmp(f->tf_fb->tfb_tcp_block_name, fs->function_set_name) == 0) {
287 blk = f->tf_fb;
288 break;
289 }
290 }
291 return(blk);
292 }
293
294 static struct tcp_function_block *
295 find_tcp_fb_locked(struct tcp_function_block *blk, struct tcp_function **s)
296 {
297 struct tcp_function_block *rblk=NULL;
298 struct tcp_function *f;
299
300 TAILQ_FOREACH(f, &t_functions, tf_next) {
301 if (f->tf_fb == blk) {
302 rblk = blk;
303 if (s) {
304 *s = f;
305 }
306 break;
307 }
308 }
309 return (rblk);
310 }
311
312 struct tcp_function_block *
313 find_and_ref_tcp_functions(struct tcp_function_set *fs)
314 {
315 struct tcp_function_block *blk;
316
317 rw_rlock(&tcp_function_lock);
318 blk = find_tcp_functions_locked(fs);
319 if (blk)
320 refcount_acquire(&blk->tfb_refcnt);
321 rw_runlock(&tcp_function_lock);
322 return(blk);
323 }
324
325 struct tcp_function_block *
326 find_and_ref_tcp_fb(struct tcp_function_block *blk)
327 {
328 struct tcp_function_block *rblk;
329
330 rw_rlock(&tcp_function_lock);
331 rblk = find_tcp_fb_locked(blk, NULL);
332 if (rblk)
333 refcount_acquire(&rblk->tfb_refcnt);
334 rw_runlock(&tcp_function_lock);
335 return(rblk);
336 }
337
338
339 static int
340 sysctl_net_inet_default_tcp_functions(SYSCTL_HANDLER_ARGS)
341 {
342 int error=ENOENT;
343 struct tcp_function_set fs;
344 struct tcp_function_block *blk;
345
346 memset(&fs, 0, sizeof(fs));
347 rw_rlock(&tcp_function_lock);
348 blk = find_tcp_fb_locked(tcp_func_set_ptr, NULL);
349 if (blk) {
350 /* Found him */
351 strcpy(fs.function_set_name, blk->tfb_tcp_block_name);
352 fs.pcbcnt = blk->tfb_refcnt;
353 }
354 rw_runlock(&tcp_function_lock);
355 error = sysctl_handle_string(oidp, fs.function_set_name,
356 sizeof(fs.function_set_name), req);
357
358 /* Check for error or no change */
359 if (error != 0 || req->newptr == NULL)
360 return(error);
361
362 rw_wlock(&tcp_function_lock);
363 blk = find_tcp_functions_locked(&fs);
364 if ((blk == NULL) ||
365 (blk->tfb_flags & TCP_FUNC_BEING_REMOVED)) {
366 error = ENOENT;
367 goto done;
368 }
369 tcp_func_set_ptr = blk;
370 done:
371 rw_wunlock(&tcp_function_lock);
372 return (error);
373 }
374
375 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, functions_default,
376 CTLTYPE_STRING | CTLFLAG_RW,
377 NULL, 0, sysctl_net_inet_default_tcp_functions, "A",
378 "Set/get the default TCP functions");
379
380 static int
381 sysctl_net_inet_list_available(SYSCTL_HANDLER_ARGS)
382 {
383 int error, cnt, linesz;
384 struct tcp_function *f;
385 char *buffer, *cp;
386 size_t bufsz, outsz;
387
388 cnt = 0;
389 rw_rlock(&tcp_function_lock);
390 TAILQ_FOREACH(f, &t_functions, tf_next) {
391 cnt++;
392 }
393 rw_runlock(&tcp_function_lock);
394
395 bufsz = (cnt+2) * (TCP_FUNCTION_NAME_LEN_MAX + 12) + 1;
396 buffer = malloc(bufsz, M_TEMP, M_WAITOK);
397
398 error = 0;
399 cp = buffer;
400
401 linesz = snprintf(cp, bufsz, "\n%-32s%c %s\n", "Stack", 'D', "PCB count");
402 cp += linesz;
403 bufsz -= linesz;
404 outsz = linesz;
405
406 rw_rlock(&tcp_function_lock);
407 TAILQ_FOREACH(f, &t_functions, tf_next) {
408 linesz = snprintf(cp, bufsz, "%-32s%c %u\n",
409 f->tf_fb->tfb_tcp_block_name,
410 (f->tf_fb == tcp_func_set_ptr) ? '*' : ' ',
411 f->tf_fb->tfb_refcnt);
412 if (linesz >= bufsz) {
413 error = EOVERFLOW;
414 break;
415 }
416 cp += linesz;
417 bufsz -= linesz;
418 outsz += linesz;
419 }
420 rw_runlock(&tcp_function_lock);
421 if (error == 0)
422 error = sysctl_handle_string(oidp, buffer, outsz + 1, req);
423 free(buffer, M_TEMP);
424 return (error);
425 }
426
427 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, functions_available,
428 CTLTYPE_STRING|CTLFLAG_RD,
429 NULL, 0, sysctl_net_inet_list_available, "A",
430 "list available TCP Function sets");
431
432 /*
433 * Target size of TCP PCB hash tables. Must be a power of two.
434 *
435 * Note that this can be overridden by the kernel environment
436 * variable net.inet.tcp.tcbhashsize
437 */
438 #ifndef TCBHASHSIZE
439 #define TCBHASHSIZE 0
440 #endif
441
442 /*
443 * XXX
444 * Callouts should be moved into struct tcp directly. They are currently
445 * separate because the tcpcb structure is exported to userland for sysctl
446 * parsing purposes, which do not know about callouts.
447 */
448 struct tcpcb_mem {
449 struct tcpcb tcb;
450 struct tcp_timer tt;
451 struct cc_var ccv;
452 struct osd osd;
453 };
454
455 static VNET_DEFINE(uma_zone_t, tcpcb_zone);
456 #define V_tcpcb_zone VNET(tcpcb_zone)
457
458 MALLOC_DEFINE(M_TCPLOG, "tcplog", "TCP address and flags print buffers");
459 MALLOC_DEFINE(M_TCPFUNCTIONS, "tcpfunc", "TCP function set memory");
460
461 static struct mtx isn_mtx;
462
463 #define ISN_LOCK_INIT() mtx_init(&isn_mtx, "isn_mtx", NULL, MTX_DEF)
464 #define ISN_LOCK() mtx_lock(&isn_mtx)
465 #define ISN_UNLOCK() mtx_unlock(&isn_mtx)
466
467 /*
468 * TCP initialization.
469 */
470 static void
471 tcp_zone_change(void *tag)
472 {
473
474 uma_zone_set_max(V_tcbinfo.ipi_zone, maxsockets);
475 uma_zone_set_max(V_tcpcb_zone, maxsockets);
476 tcp_tw_zone_change();
477 }
478
479 static int
480 tcp_inpcb_init(void *mem, int size, int flags)
481 {
482 struct inpcb *inp = mem;
483
484 INP_LOCK_INIT(inp, "inp", "tcpinp");
485 return (0);
486 }
487
488 /*
489 * Take a value and get the next power of 2 that doesn't overflow.
490 * Used to size the tcp_inpcb hash buckets.
491 */
492 static int
493 maketcp_hashsize(int size)
494 {
495 int hashsize;
496
497 /*
498 * auto tune.
499 * get the next power of 2 higher than maxsockets.
500 */
501 hashsize = 1 << fls(size);
502 /* catch overflow, and just go one power of 2 smaller */
503 if (hashsize < size) {
504 hashsize = 1 << (fls(size) - 1);
505 }
506 return (hashsize);
507 }
508
509 int
510 register_tcp_functions(struct tcp_function_block *blk, int wait)
511 {
512 struct tcp_function_block *lblk;
513 struct tcp_function *n;
514 struct tcp_function_set fs;
515
516 if (t_functions_inited == 0) {
517 init_tcp_functions();
518 }
519 if ((blk->tfb_tcp_output == NULL) ||
520 (blk->tfb_tcp_do_segment == NULL) ||
521 (blk->tfb_tcp_ctloutput == NULL) ||
522 (strlen(blk->tfb_tcp_block_name) == 0)) {
523 /*
524 * These functions are required and you
525 * need a name.
526 */
527 return (EINVAL);
528 }
529 if (blk->tfb_tcp_timer_stop_all ||
530 blk->tfb_tcp_timer_activate ||
531 blk->tfb_tcp_timer_active ||
532 blk->tfb_tcp_timer_stop) {
533 /*
534 * If you define one timer function you
535 * must have them all.
536 */
537 if ((blk->tfb_tcp_timer_stop_all == NULL) ||
538 (blk->tfb_tcp_timer_activate == NULL) ||
539 (blk->tfb_tcp_timer_active == NULL) ||
540 (blk->tfb_tcp_timer_stop == NULL)) {
541 return (EINVAL);
542 }
543 }
544 n = malloc(sizeof(struct tcp_function), M_TCPFUNCTIONS, wait);
545 if (n == NULL) {
546 return (ENOMEM);
547 }
548 n->tf_fb = blk;
549 strcpy(fs.function_set_name, blk->tfb_tcp_block_name);
550 rw_wlock(&tcp_function_lock);
551 lblk = find_tcp_functions_locked(&fs);
552 if (lblk) {
553 /* Duplicate name space not allowed */
554 rw_wunlock(&tcp_function_lock);
555 free(n, M_TCPFUNCTIONS);
556 return (EALREADY);
557 }
558 refcount_init(&blk->tfb_refcnt, 0);
559 blk->tfb_flags = 0;
560 TAILQ_INSERT_TAIL(&t_functions, n, tf_next);
561 rw_wunlock(&tcp_function_lock);
562 return(0);
563 }
564
565 int
566 deregister_tcp_functions(struct tcp_function_block *blk)
567 {
568 struct tcp_function_block *lblk;
569 struct tcp_function *f;
570 int error=ENOENT;
571
572 if (strcmp(blk->tfb_tcp_block_name, "default") == 0) {
573 /* You can't un-register the default */
574 return (EPERM);
575 }
576 rw_wlock(&tcp_function_lock);
577 if (blk == tcp_func_set_ptr) {
578 /* You can't free the current default */
579 rw_wunlock(&tcp_function_lock);
580 return (EBUSY);
581 }
582 if (blk->tfb_refcnt) {
583 /* Still tcb attached, mark it. */
584 blk->tfb_flags |= TCP_FUNC_BEING_REMOVED;
585 rw_wunlock(&tcp_function_lock);
586 return (EBUSY);
587 }
588 lblk = find_tcp_fb_locked(blk, &f);
589 if (lblk) {
590 /* Found */
591 TAILQ_REMOVE(&t_functions, f, tf_next);
592 f->tf_fb = NULL;
593 free(f, M_TCPFUNCTIONS);
594 error = 0;
595 }
596 rw_wunlock(&tcp_function_lock);
597 return (error);
598 }
599
600 void
601 tcp_init(void)
602 {
603 const char *tcbhash_tuneable;
604 int hashsize;
605
606 tcbhash_tuneable = "net.inet.tcp.tcbhashsize";
607
608 if (hhook_head_register(HHOOK_TYPE_TCP, HHOOK_TCP_EST_IN,
609 &V_tcp_hhh[HHOOK_TCP_EST_IN], HHOOK_NOWAIT|HHOOK_HEADISINVNET) != 0)
610 printf("%s: WARNING: unable to register helper hook\n", __func__);
611 if (hhook_head_register(HHOOK_TYPE_TCP, HHOOK_TCP_EST_OUT,
612 &V_tcp_hhh[HHOOK_TCP_EST_OUT], HHOOK_NOWAIT|HHOOK_HEADISINVNET) != 0)
613 printf("%s: WARNING: unable to register helper hook\n", __func__);
614 hashsize = TCBHASHSIZE;
615 TUNABLE_INT_FETCH(tcbhash_tuneable, &hashsize);
616 if (hashsize == 0) {
617 /*
618 * Auto tune the hash size based on maxsockets.
619 * A perfect hash would have a 1:1 mapping
620 * (hashsize = maxsockets) however it's been
621 * suggested that O(2) average is better.
622 */
623 hashsize = maketcp_hashsize(maxsockets / 4);
624 /*
625 * Our historical default is 512,
626 * do not autotune lower than this.
627 */
628 if (hashsize < 512)
629 hashsize = 512;
630 if (bootverbose && IS_DEFAULT_VNET(curvnet))
631 printf("%s: %s auto tuned to %d\n", __func__,
632 tcbhash_tuneable, hashsize);
633 }
634 /*
635 * We require a hashsize to be a power of two.
636 * Previously if it was not a power of two we would just reset it
637 * back to 512, which could be a nasty surprise if you did not notice
638 * the error message.
639 * Instead what we do is clip it to the closest power of two lower
640 * than the specified hash value.
641 */
642 if (!powerof2(hashsize)) {
643 int oldhashsize = hashsize;
644
645 hashsize = maketcp_hashsize(hashsize);
646 /* prevent absurdly low value */
647 if (hashsize < 16)
648 hashsize = 16;
649 printf("%s: WARNING: TCB hash size not a power of 2, "
650 "clipped from %d to %d.\n", __func__, oldhashsize,
651 hashsize);
652 }
653 in_pcbinfo_init(&V_tcbinfo, "tcp", &V_tcb, hashsize, hashsize,
654 "tcp_inpcb", tcp_inpcb_init, NULL, 0, IPI_HASHFIELDS_4TUPLE);
655
656 /*
657 * These have to be type stable for the benefit of the timers.
658 */
659 V_tcpcb_zone = uma_zcreate("tcpcb", sizeof(struct tcpcb_mem),
660 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
661 uma_zone_set_max(V_tcpcb_zone, maxsockets);
662 uma_zone_set_warning(V_tcpcb_zone, "kern.ipc.maxsockets limit reached");
663
664 tcp_tw_init();
665 syncache_init();
666 tcp_hc_init();
667
668 TUNABLE_INT_FETCH("net.inet.tcp.sack.enable", &V_tcp_do_sack);
669 V_sack_hole_zone = uma_zcreate("sackhole", sizeof(struct sackhole),
670 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
671
672 /* Skip initialization of globals for non-default instances. */
673 if (!IS_DEFAULT_VNET(curvnet))
674 return;
675
676 tcp_reass_global_init();
677
678 /* XXX virtualize those bellow? */
679 tcp_delacktime = TCPTV_DELACK;
680 tcp_keepinit = TCPTV_KEEP_INIT;
681 tcp_keepidle = TCPTV_KEEP_IDLE;
682 tcp_keepintvl = TCPTV_KEEPINTVL;
683 tcp_maxpersistidle = TCPTV_KEEP_IDLE;
684 tcp_msl = TCPTV_MSL;
685 tcp_rexmit_min = TCPTV_MIN;
686 if (tcp_rexmit_min < 1)
687 tcp_rexmit_min = 1;
688 tcp_persmin = TCPTV_PERSMIN;
689 tcp_persmax = TCPTV_PERSMAX;
690 tcp_rexmit_slop = TCPTV_CPU_VAR;
691 tcp_finwait2_timeout = TCPTV_FINWAIT2_TIMEOUT;
692 tcp_tcbhashsize = hashsize;
693 /* Setup the tcp function block list */
694 init_tcp_functions();
695 register_tcp_functions(&tcp_def_funcblk, M_WAITOK);
696
697 if (tcp_soreceive_stream) {
698 #ifdef INET
699 tcp_usrreqs.pru_soreceive = soreceive_stream;
700 #endif
701 #ifdef INET6
702 tcp6_usrreqs.pru_soreceive = soreceive_stream;
703 #endif /* INET6 */
704 }
705
706 #ifdef INET6
707 #define TCP_MINPROTOHDR (sizeof(struct ip6_hdr) + sizeof(struct tcphdr))
708 #else /* INET6 */
709 #define TCP_MINPROTOHDR (sizeof(struct tcpiphdr))
710 #endif /* INET6 */
711 if (max_protohdr < TCP_MINPROTOHDR)
712 max_protohdr = TCP_MINPROTOHDR;
713 if (max_linkhdr + TCP_MINPROTOHDR > MHLEN)
714 panic("tcp_init");
715 #undef TCP_MINPROTOHDR
716
717 ISN_LOCK_INIT();
718 EVENTHANDLER_REGISTER(shutdown_pre_sync, tcp_fini, NULL,
719 SHUTDOWN_PRI_DEFAULT);
720 EVENTHANDLER_REGISTER(maxsockets_change, tcp_zone_change, NULL,
721 EVENTHANDLER_PRI_ANY);
722 #ifdef TCPPCAP
723 tcp_pcap_init();
724 #endif
725
726 #ifdef TCP_RFC7413
727 tcp_fastopen_init();
728 #endif
729 }
730
731 #ifdef VIMAGE
732 static void
733 tcp_destroy(void *unused __unused)
734 {
735 int error, n;
736
737 /*
738 * All our processes are gone, all our sockets should be cleaned
739 * up, which means, we should be past the tcp_discardcb() calls.
740 * Sleep to let all tcpcb timers really disappear and cleanup.
741 */
742 for (;;) {
743 INP_LIST_RLOCK(&V_tcbinfo);
744 n = V_tcbinfo.ipi_count;
745 INP_LIST_RUNLOCK(&V_tcbinfo);
746 if (n == 0)
747 break;
748 pause("tcpdes", hz / 10);
749 }
750 tcp_hc_destroy();
751 syncache_destroy();
752 tcp_tw_destroy();
753 in_pcbinfo_destroy(&V_tcbinfo);
754 /* tcp_discardcb() clears the sack_holes up. */
755 uma_zdestroy(V_sack_hole_zone);
756 uma_zdestroy(V_tcpcb_zone);
757
758 #ifdef TCP_RFC7413
759 /*
760 * Cannot free the zone until all tcpcbs are released as we attach
761 * the allocations to them.
762 */
763 tcp_fastopen_destroy();
764 #endif
765
766 error = hhook_head_deregister(V_tcp_hhh[HHOOK_TCP_EST_IN]);
767 if (error != 0) {
768 printf("%s: WARNING: unable to deregister helper hook "
769 "type=%d, id=%d: error %d returned\n", __func__,
770 HHOOK_TYPE_TCP, HHOOK_TCP_EST_IN, error);
771 }
772 error = hhook_head_deregister(V_tcp_hhh[HHOOK_TCP_EST_OUT]);
773 if (error != 0) {
774 printf("%s: WARNING: unable to deregister helper hook "
775 "type=%d, id=%d: error %d returned\n", __func__,
776 HHOOK_TYPE_TCP, HHOOK_TCP_EST_OUT, error);
777 }
778 }
779 VNET_SYSUNINIT(tcp, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH, tcp_destroy, NULL);
780 #endif
781
782 void
783 tcp_fini(void *xtp)
784 {
785
786 }
787
788 /*
789 * Fill in the IP and TCP headers for an outgoing packet, given the tcpcb.
790 * tcp_template used to store this data in mbufs, but we now recopy it out
791 * of the tcpcb each time to conserve mbufs.
792 */
793 void
794 tcpip_fillheaders(struct inpcb *inp, void *ip_ptr, void *tcp_ptr)
795 {
796 struct tcphdr *th = (struct tcphdr *)tcp_ptr;
797
798 INP_WLOCK_ASSERT(inp);
799
800 #ifdef INET6
801 if ((inp->inp_vflag & INP_IPV6) != 0) {
802 struct ip6_hdr *ip6;
803
804 ip6 = (struct ip6_hdr *)ip_ptr;
805 ip6->ip6_flow = (ip6->ip6_flow & ~IPV6_FLOWINFO_MASK) |
806 (inp->inp_flow & IPV6_FLOWINFO_MASK);
807 ip6->ip6_vfc = (ip6->ip6_vfc & ~IPV6_VERSION_MASK) |
808 (IPV6_VERSION & IPV6_VERSION_MASK);
809 ip6->ip6_nxt = IPPROTO_TCP;
810 ip6->ip6_plen = htons(sizeof(struct tcphdr));
811 ip6->ip6_src = inp->in6p_laddr;
812 ip6->ip6_dst = inp->in6p_faddr;
813 }
814 #endif /* INET6 */
815 #if defined(INET6) && defined(INET)
816 else
817 #endif
818 #ifdef INET
819 {
820 struct ip *ip;
821
822 ip = (struct ip *)ip_ptr;
823 ip->ip_v = IPVERSION;
824 ip->ip_hl = 5;
825 ip->ip_tos = inp->inp_ip_tos;
826 ip->ip_len = 0;
827 ip->ip_id = 0;
828 ip->ip_off = 0;
829 ip->ip_ttl = inp->inp_ip_ttl;
830 ip->ip_sum = 0;
831 ip->ip_p = IPPROTO_TCP;
832 ip->ip_src = inp->inp_laddr;
833 ip->ip_dst = inp->inp_faddr;
834 }
835 #endif /* INET */
836 th->th_sport = inp->inp_lport;
837 th->th_dport = inp->inp_fport;
838 th->th_seq = 0;
839 th->th_ack = 0;
840 th->th_x2 = 0;
841 th->th_off = 5;
842 th->th_flags = 0;
843 th->th_win = 0;
844 th->th_urp = 0;
845 th->th_sum = 0; /* in_pseudo() is called later for ipv4 */
846 }
847
848 /*
849 * Create template to be used to send tcp packets on a connection.
850 * Allocates an mbuf and fills in a skeletal tcp/ip header. The only
851 * use for this function is in keepalives, which use tcp_respond.
852 */
853 struct tcptemp *
854 tcpip_maketemplate(struct inpcb *inp)
855 {
856 struct tcptemp *t;
857
858 t = malloc(sizeof(*t), M_TEMP, M_NOWAIT);
859 if (t == NULL)
860 return (NULL);
861 tcpip_fillheaders(inp, (void *)&t->tt_ipgen, (void *)&t->tt_t);
862 return (t);
863 }
864
865 /*
866 * Send a single message to the TCP at address specified by
867 * the given TCP/IP header. If m == NULL, then we make a copy
868 * of the tcpiphdr at th and send directly to the addressed host.
869 * This is used to force keep alive messages out using the TCP
870 * template for a connection. If flags are given then we send
871 * a message back to the TCP which originated the segment th,
872 * and discard the mbuf containing it and any other attached mbufs.
873 *
874 * In any case the ack and sequence number of the transmitted
875 * segment are as specified by the parameters.
876 *
877 * NOTE: If m != NULL, then th must point to *inside* the mbuf.
878 */
879 void
880 tcp_respond(struct tcpcb *tp, void *ipgen, struct tcphdr *th, struct mbuf *m,
881 tcp_seq ack, tcp_seq seq, int flags)
882 {
883 struct tcpopt to;
884 struct inpcb *inp;
885 struct ip *ip;
886 struct mbuf *optm;
887 struct tcphdr *nth;
888 u_char *optp;
889 #ifdef INET6
890 struct ip6_hdr *ip6;
891 int isipv6;
892 #endif /* INET6 */
893 int optlen, tlen, win;
894 bool incl_opts;
895
896 KASSERT(tp != NULL || m != NULL, ("tcp_respond: tp and m both NULL"));
897
898 #ifdef INET6
899 isipv6 = ((struct ip *)ipgen)->ip_v == (IPV6_VERSION >> 4);
900 ip6 = ipgen;
901 #endif /* INET6 */
902 ip = ipgen;
903
904 if (tp != NULL) {
905 inp = tp->t_inpcb;
906 KASSERT(inp != NULL, ("tcp control block w/o inpcb"));
907 INP_WLOCK_ASSERT(inp);
908 } else
909 inp = NULL;
910
911 incl_opts = false;
912 win = 0;
913 if (tp != NULL) {
914 if (!(flags & TH_RST)) {
915 win = sbspace(&inp->inp_socket->so_rcv);
916 if (win > (long)TCP_MAXWIN << tp->rcv_scale)
917 win = (long)TCP_MAXWIN << tp->rcv_scale;
918 }
919 if ((tp->t_flags & TF_NOOPT) == 0)
920 incl_opts = true;
921 }
922 if (m == NULL) {
923 m = m_gethdr(M_NOWAIT, MT_DATA);
924 if (m == NULL)
925 return;
926 m->m_data += max_linkhdr;
927 #ifdef INET6
928 if (isipv6) {
929 bcopy((caddr_t)ip6, mtod(m, caddr_t),
930 sizeof(struct ip6_hdr));
931 ip6 = mtod(m, struct ip6_hdr *);
932 nth = (struct tcphdr *)(ip6 + 1);
933 } else
934 #endif /* INET6 */
935 {
936 bcopy((caddr_t)ip, mtod(m, caddr_t), sizeof(struct ip));
937 ip = mtod(m, struct ip *);
938 nth = (struct tcphdr *)(ip + 1);
939 }
940 bcopy((caddr_t)th, (caddr_t)nth, sizeof(struct tcphdr));
941 flags = TH_ACK;
942 } else if (!M_WRITABLE(m)) {
943 struct mbuf *n;
944
945 /* Can't reuse 'm', allocate a new mbuf. */
946 n = m_gethdr(M_NOWAIT, MT_DATA);
947 if (n == NULL) {
948 m_freem(m);
949 return;
950 }
951
952 if (!m_dup_pkthdr(n, m, M_NOWAIT)) {
953 m_freem(m);
954 m_freem(n);
955 return;
956 }
957
958 n->m_data += max_linkhdr;
959 /* m_len is set later */
960 #define xchg(a,b,type) { type t; t=a; a=b; b=t; }
961 #ifdef INET6
962 if (isipv6) {
963 bcopy((caddr_t)ip6, mtod(n, caddr_t),
964 sizeof(struct ip6_hdr));
965 ip6 = mtod(n, struct ip6_hdr *);
966 xchg(ip6->ip6_dst, ip6->ip6_src, struct in6_addr);
967 nth = (struct tcphdr *)(ip6 + 1);
968 } else
969 #endif /* INET6 */
970 {
971 bcopy((caddr_t)ip, mtod(n, caddr_t), sizeof(struct ip));
972 ip = mtod(n, struct ip *);
973 xchg(ip->ip_dst.s_addr, ip->ip_src.s_addr, uint32_t);
974 nth = (struct tcphdr *)(ip + 1);
975 }
976 bcopy((caddr_t)th, (caddr_t)nth, sizeof(struct tcphdr));
977 xchg(nth->th_dport, nth->th_sport, uint16_t);
978 th = nth;
979 m_freem(m);
980 m = n;
981 } else {
982 /*
983 * reuse the mbuf.
984 * XXX MRT We inherit the FIB, which is lucky.
985 */
986 m_freem(m->m_next);
987 m->m_next = NULL;
988 m->m_data = (caddr_t)ipgen;
989 /* m_len is set later */
990 #ifdef INET6
991 if (isipv6) {
992 xchg(ip6->ip6_dst, ip6->ip6_src, struct in6_addr);
993 nth = (struct tcphdr *)(ip6 + 1);
994 } else
995 #endif /* INET6 */
996 {
997 xchg(ip->ip_dst.s_addr, ip->ip_src.s_addr, uint32_t);
998 nth = (struct tcphdr *)(ip + 1);
999 }
1000 if (th != nth) {
1001 /*
1002 * this is usually a case when an extension header
1003 * exists between the IPv6 header and the
1004 * TCP header.
1005 */
1006 nth->th_sport = th->th_sport;
1007 nth->th_dport = th->th_dport;
1008 }
1009 xchg(nth->th_dport, nth->th_sport, uint16_t);
1010 #undef xchg
1011 }
1012 tlen = 0;
1013 #ifdef INET6
1014 if (isipv6)
1015 tlen = sizeof (struct ip6_hdr) + sizeof (struct tcphdr);
1016 #endif
1017 #if defined(INET) && defined(INET6)
1018 else
1019 #endif
1020 #ifdef INET
1021 tlen = sizeof (struct tcpiphdr);
1022 #endif
1023 #ifdef INVARIANTS
1024 m->m_len = 0;
1025 KASSERT(M_TRAILINGSPACE(m) >= tlen,
1026 ("Not enough trailing space for message (m=%p, need=%d, have=%ld)",
1027 m, tlen, (long)M_TRAILINGSPACE(m)));
1028 #endif
1029 m->m_len = tlen;
1030 to.to_flags = 0;
1031 if (incl_opts) {
1032 /* Make sure we have room. */
1033 if (M_TRAILINGSPACE(m) < TCP_MAXOLEN) {
1034 m->m_next = m_get(M_NOWAIT, MT_DATA);
1035 if (m->m_next) {
1036 optp = mtod(m->m_next, u_char *);
1037 optm = m->m_next;
1038 } else
1039 incl_opts = false;
1040 } else {
1041 optp = (u_char *) (nth + 1);
1042 optm = m;
1043 }
1044 }
1045 if (incl_opts) {
1046 /* Timestamps. */
1047 if (tp->t_flags & TF_RCVD_TSTMP) {
1048 to.to_tsval = tcp_ts_getticks() + tp->ts_offset;
1049 to.to_tsecr = tp->ts_recent;
1050 to.to_flags |= TOF_TS;
1051 }
1052 #ifdef TCP_SIGNATURE
1053 /* TCP-MD5 (RFC2385). */
1054 if (tp->t_flags & TF_SIGNATURE)
1055 to.to_flags |= TOF_SIGNATURE;
1056 #endif
1057
1058 /* Add the options. */
1059 tlen += optlen = tcp_addoptions(&to, optp);
1060
1061 /* Update m_len in the correct mbuf. */
1062 optm->m_len += optlen;
1063 } else
1064 optlen = 0;
1065 #ifdef INET6
1066 if (isipv6) {
1067 ip6->ip6_flow = 0;
1068 ip6->ip6_vfc = IPV6_VERSION;
1069 ip6->ip6_nxt = IPPROTO_TCP;
1070 ip6->ip6_plen = htons(tlen - sizeof(*ip6));
1071 }
1072 #endif
1073 #if defined(INET) && defined(INET6)
1074 else
1075 #endif
1076 #ifdef INET
1077 {
1078 ip->ip_len = htons(tlen);
1079 ip->ip_ttl = V_ip_defttl;
1080 if (V_path_mtu_discovery)
1081 ip->ip_off |= htons(IP_DF);
1082 }
1083 #endif
1084 m->m_pkthdr.len = tlen;
1085 m->m_pkthdr.rcvif = NULL;
1086 #ifdef MAC
1087 if (inp != NULL) {
1088 /*
1089 * Packet is associated with a socket, so allow the
1090 * label of the response to reflect the socket label.
1091 */
1092 INP_WLOCK_ASSERT(inp);
1093 mac_inpcb_create_mbuf(inp, m);
1094 } else {
1095 /*
1096 * Packet is not associated with a socket, so possibly
1097 * update the label in place.
1098 */
1099 mac_netinet_tcp_reply(m);
1100 }
1101 #endif
1102 nth->th_seq = htonl(seq);
1103 nth->th_ack = htonl(ack);
1104 nth->th_x2 = 0;
1105 nth->th_off = (sizeof (struct tcphdr) + optlen) >> 2;
1106 nth->th_flags = flags;
1107 if (tp != NULL)
1108 nth->th_win = htons((u_short) (win >> tp->rcv_scale));
1109 else
1110 nth->th_win = htons((u_short)win);
1111 nth->th_urp = 0;
1112
1113 #ifdef TCP_SIGNATURE
1114 if (to.to_flags & TOF_SIGNATURE) {
1115 tcp_signature_compute(m, 0, 0, optlen, to.to_signature,
1116 IPSEC_DIR_OUTBOUND);
1117 }
1118 #endif
1119
1120 m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum);
1121 #ifdef INET6
1122 if (isipv6) {
1123 m->m_pkthdr.csum_flags = CSUM_TCP_IPV6;
1124 nth->th_sum = in6_cksum_pseudo(ip6,
1125 tlen - sizeof(struct ip6_hdr), IPPROTO_TCP, 0);
1126 ip6->ip6_hlim = in6_selecthlim(tp != NULL ? tp->t_inpcb :
1127 NULL, NULL);
1128 }
1129 #endif /* INET6 */
1130 #if defined(INET6) && defined(INET)
1131 else
1132 #endif
1133 #ifdef INET
1134 {
1135 m->m_pkthdr.csum_flags = CSUM_TCP;
1136 nth->th_sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr,
1137 htons((u_short)(tlen - sizeof(struct ip) + ip->ip_p)));
1138 }
1139 #endif /* INET */
1140 #ifdef TCPDEBUG
1141 if (tp == NULL || (inp->inp_socket->so_options & SO_DEBUG))
1142 tcp_trace(TA_OUTPUT, 0, tp, mtod(m, void *), th, 0);
1143 #endif
1144 TCP_PROBE3(debug__output, tp, th, mtod(m, const char *));
1145 if (flags & TH_RST)
1146 TCP_PROBE5(accept__refused, NULL, NULL, mtod(m, const char *),
1147 tp, nth);
1148
1149 TCP_PROBE5(send, NULL, tp, mtod(m, const char *), tp, nth);
1150 #ifdef INET6
1151 if (isipv6)
1152 (void) ip6_output(m, NULL, NULL, 0, NULL, NULL, inp);
1153 #endif /* INET6 */
1154 #if defined(INET) && defined(INET6)
1155 else
1156 #endif
1157 #ifdef INET
1158 (void) ip_output(m, NULL, NULL, 0, NULL, inp);
1159 #endif
1160 }
1161
1162 /*
1163 * Create a new TCP control block, making an
1164 * empty reassembly queue and hooking it to the argument
1165 * protocol control block. The `inp' parameter must have
1166 * come from the zone allocator set up in tcp_init().
1167 */
1168 struct tcpcb *
1169 tcp_newtcpcb(struct inpcb *inp)
1170 {
1171 struct tcpcb_mem *tm;
1172 struct tcpcb *tp;
1173 #ifdef INET6
1174 int isipv6 = (inp->inp_vflag & INP_IPV6) != 0;
1175 #endif /* INET6 */
1176
1177 tm = uma_zalloc(V_tcpcb_zone, M_NOWAIT | M_ZERO);
1178 if (tm == NULL)
1179 return (NULL);
1180 tp = &tm->tcb;
1181
1182 /* Initialise cc_var struct for this tcpcb. */
1183 tp->ccv = &tm->ccv;
1184 tp->ccv->type = IPPROTO_TCP;
1185 tp->ccv->ccvc.tcp = tp;
1186 rw_rlock(&tcp_function_lock);
1187 tp->t_fb = tcp_func_set_ptr;
1188 refcount_acquire(&tp->t_fb->tfb_refcnt);
1189 rw_runlock(&tcp_function_lock);
1190 if (tp->t_fb->tfb_tcp_fb_init) {
1191 (*tp->t_fb->tfb_tcp_fb_init)(tp);
1192 }
1193 /*
1194 * Use the current system default CC algorithm.
1195 */
1196 CC_LIST_RLOCK();
1197 KASSERT(!STAILQ_EMPTY(&cc_list), ("cc_list is empty!"));
1198 CC_ALGO(tp) = CC_DEFAULT();
1199 CC_LIST_RUNLOCK();
1200
1201 if (CC_ALGO(tp)->cb_init != NULL)
1202 if (CC_ALGO(tp)->cb_init(tp->ccv) > 0) {
1203 if (tp->t_fb->tfb_tcp_fb_fini)
1204 (*tp->t_fb->tfb_tcp_fb_fini)(tp);
1205 refcount_release(&tp->t_fb->tfb_refcnt);
1206 uma_zfree(V_tcpcb_zone, tm);
1207 return (NULL);
1208 }
1209
1210 tp->osd = &tm->osd;
1211 if (khelp_init_osd(HELPER_CLASS_TCP, tp->osd)) {
1212 if (tp->t_fb->tfb_tcp_fb_fini)
1213 (*tp->t_fb->tfb_tcp_fb_fini)(tp);
1214 refcount_release(&tp->t_fb->tfb_refcnt);
1215 uma_zfree(V_tcpcb_zone, tm);
1216 return (NULL);
1217 }
1218
1219 #ifdef VIMAGE
1220 tp->t_vnet = inp->inp_vnet;
1221 #endif
1222 tp->t_timers = &tm->tt;
1223 /* LIST_INIT(&tp->t_segq); */ /* XXX covered by M_ZERO */
1224 tp->t_maxseg =
1225 #ifdef INET6
1226 isipv6 ? V_tcp_v6mssdflt :
1227 #endif /* INET6 */
1228 V_tcp_mssdflt;
1229
1230 /* Set up our timeouts. */
1231 callout_init(&tp->t_timers->tt_rexmt, 1);
1232 callout_init(&tp->t_timers->tt_persist, 1);
1233 callout_init(&tp->t_timers->tt_keep, 1);
1234 callout_init(&tp->t_timers->tt_2msl, 1);
1235 callout_init(&tp->t_timers->tt_delack, 1);
1236
1237 if (V_tcp_do_rfc1323)
1238 tp->t_flags = (TF_REQ_SCALE|TF_REQ_TSTMP);
1239 if (V_tcp_do_sack)
1240 tp->t_flags |= TF_SACK_PERMIT;
1241 TAILQ_INIT(&tp->snd_holes);
1242 /*
1243 * The tcpcb will hold a reference on its inpcb until tcp_discardcb()
1244 * is called.
1245 */
1246 in_pcbref(inp); /* Reference for tcpcb */
1247 tp->t_inpcb = inp;
1248
1249 /*
1250 * Init srtt to TCPTV_SRTTBASE (0), so we can tell that we have no
1251 * rtt estimate. Set rttvar so that srtt + 4 * rttvar gives
1252 * reasonable initial retransmit time.
1253 */
1254 tp->t_srtt = TCPTV_SRTTBASE;
1255 tp->t_rttvar = ((TCPTV_RTOBASE - TCPTV_SRTTBASE) << TCP_RTTVAR_SHIFT) / 4;
1256 tp->t_rttmin = tcp_rexmit_min;
1257 tp->t_rxtcur = TCPTV_RTOBASE;
1258 tp->snd_cwnd = TCP_MAXWIN << TCP_MAX_WINSHIFT;
1259 tp->snd_ssthresh = TCP_MAXWIN << TCP_MAX_WINSHIFT;
1260 tp->t_rcvtime = ticks;
1261 /*
1262 * IPv4 TTL initialization is necessary for an IPv6 socket as well,
1263 * because the socket may be bound to an IPv6 wildcard address,
1264 * which may match an IPv4-mapped IPv6 address.
1265 */
1266 inp->inp_ip_ttl = V_ip_defttl;
1267 inp->inp_ppcb = tp;
1268 #ifdef TCPPCAP
1269 /*
1270 * Init the TCP PCAP queues.
1271 */
1272 tcp_pcap_tcpcb_init(tp);
1273 #endif
1274 return (tp); /* XXX */
1275 }
1276
1277 /*
1278 * Switch the congestion control algorithm back to NewReno for any active
1279 * control blocks using an algorithm which is about to go away.
1280 * This ensures the CC framework can allow the unload to proceed without leaving
1281 * any dangling pointers which would trigger a panic.
1282 * Returning non-zero would inform the CC framework that something went wrong
1283 * and it would be unsafe to allow the unload to proceed. However, there is no
1284 * way for this to occur with this implementation so we always return zero.
1285 */
1286 int
1287 tcp_ccalgounload(struct cc_algo *unload_algo)
1288 {
1289 struct cc_algo *tmpalgo;
1290 struct inpcb *inp;
1291 struct tcpcb *tp;
1292 VNET_ITERATOR_DECL(vnet_iter);
1293
1294 /*
1295 * Check all active control blocks across all network stacks and change
1296 * any that are using "unload_algo" back to NewReno. If "unload_algo"
1297 * requires cleanup code to be run, call it.
1298 */
1299 VNET_LIST_RLOCK();
1300 VNET_FOREACH(vnet_iter) {
1301 CURVNET_SET(vnet_iter);
1302 INP_INFO_WLOCK(&V_tcbinfo);
1303 /*
1304 * New connections already part way through being initialised
1305 * with the CC algo we're removing will not race with this code
1306 * because the INP_INFO_WLOCK is held during initialisation. We
1307 * therefore don't enter the loop below until the connection
1308 * list has stabilised.
1309 */
1310 LIST_FOREACH(inp, &V_tcb, inp_list) {
1311 INP_WLOCK(inp);
1312 /* Important to skip tcptw structs. */
1313 if (!(inp->inp_flags & INP_TIMEWAIT) &&
1314 (tp = intotcpcb(inp)) != NULL) {
1315 /*
1316 * By holding INP_WLOCK here, we are assured
1317 * that the connection is not currently
1318 * executing inside the CC module's functions
1319 * i.e. it is safe to make the switch back to
1320 * NewReno.
1321 */
1322 if (CC_ALGO(tp) == unload_algo) {
1323 tmpalgo = CC_ALGO(tp);
1324 /* NewReno does not require any init. */
1325 CC_ALGO(tp) = &newreno_cc_algo;
1326 if (tmpalgo->cb_destroy != NULL)
1327 tmpalgo->cb_destroy(tp->ccv);
1328 }
1329 }
1330 INP_WUNLOCK(inp);
1331 }
1332 INP_INFO_WUNLOCK(&V_tcbinfo);
1333 CURVNET_RESTORE();
1334 }
1335 VNET_LIST_RUNLOCK();
1336
1337 return (0);
1338 }
1339
1340 /*
1341 * Drop a TCP connection, reporting
1342 * the specified error. If connection is synchronized,
1343 * then send a RST to peer.
1344 */
1345 struct tcpcb *
1346 tcp_drop(struct tcpcb *tp, int errno)
1347 {
1348 struct socket *so = tp->t_inpcb->inp_socket;
1349
1350 INP_INFO_LOCK_ASSERT(&V_tcbinfo);
1351 INP_WLOCK_ASSERT(tp->t_inpcb);
1352
1353 if (TCPS_HAVERCVDSYN(tp->t_state)) {
1354 tcp_state_change(tp, TCPS_CLOSED);
1355 (void) tp->t_fb->tfb_tcp_output(tp);
1356 TCPSTAT_INC(tcps_drops);
1357 } else
1358 TCPSTAT_INC(tcps_conndrops);
1359 if (errno == ETIMEDOUT && tp->t_softerror)
1360 errno = tp->t_softerror;
1361 so->so_error = errno;
1362 return (tcp_close(tp));
1363 }
1364
1365 void
1366 tcp_discardcb(struct tcpcb *tp)
1367 {
1368 struct inpcb *inp = tp->t_inpcb;
1369 struct socket *so = inp->inp_socket;
1370 #ifdef INET6
1371 int isipv6 = (inp->inp_vflag & INP_IPV6) != 0;
1372 #endif /* INET6 */
1373 int released;
1374
1375 INP_WLOCK_ASSERT(inp);
1376
1377 /*
1378 * Make sure that all of our timers are stopped before we delete the
1379 * PCB.
1380 *
1381 * If stopping a timer fails, we schedule a discard function in same
1382 * callout, and the last discard function called will take care of
1383 * deleting the tcpcb.
1384 */
1385 tp->t_timers->tt_draincnt = 0;
1386 tcp_timer_stop(tp, TT_REXMT);
1387 tcp_timer_stop(tp, TT_PERSIST);
1388 tcp_timer_stop(tp, TT_KEEP);
1389 tcp_timer_stop(tp, TT_2MSL);
1390 tcp_timer_stop(tp, TT_DELACK);
1391 if (tp->t_fb->tfb_tcp_timer_stop_all) {
1392 /*
1393 * Call the stop-all function of the methods,
1394 * this function should call the tcp_timer_stop()
1395 * method with each of the function specific timeouts.
1396 * That stop will be called via the tfb_tcp_timer_stop()
1397 * which should use the async drain function of the
1398 * callout system (see tcp_var.h).
1399 */
1400 tp->t_fb->tfb_tcp_timer_stop_all(tp);
1401 }
1402
1403 /*
1404 * If we got enough samples through the srtt filter,
1405 * save the rtt and rttvar in the routing entry.
1406 * 'Enough' is arbitrarily defined as 4 rtt samples.
1407 * 4 samples is enough for the srtt filter to converge
1408 * to within enough % of the correct value; fewer samples
1409 * and we could save a bogus rtt. The danger is not high
1410 * as tcp quickly recovers from everything.
1411 * XXX: Works very well but needs some more statistics!
1412 */
1413 if (tp->t_rttupdated >= 4) {
1414 struct hc_metrics_lite metrics;
1415 u_long ssthresh;
1416
1417 bzero(&metrics, sizeof(metrics));
1418 /*
1419 * Update the ssthresh always when the conditions below
1420 * are satisfied. This gives us better new start value
1421 * for the congestion avoidance for new connections.
1422 * ssthresh is only set if packet loss occurred on a session.
1423 *
1424 * XXXRW: 'so' may be NULL here, and/or socket buffer may be
1425 * being torn down. Ideally this code would not use 'so'.
1426 */
1427 ssthresh = tp->snd_ssthresh;
1428 if (ssthresh != 0 && ssthresh < so->so_snd.sb_hiwat / 2) {
1429 /*
1430 * convert the limit from user data bytes to
1431 * packets then to packet data bytes.
1432 */
1433 ssthresh = (ssthresh + tp->t_maxseg / 2) / tp->t_maxseg;
1434 if (ssthresh < 2)
1435 ssthresh = 2;
1436 ssthresh *= (u_long)(tp->t_maxseg +
1437 #ifdef INET6
1438 (isipv6 ? sizeof (struct ip6_hdr) +
1439 sizeof (struct tcphdr) :
1440 #endif
1441 sizeof (struct tcpiphdr)
1442 #ifdef INET6
1443 )
1444 #endif
1445 );
1446 } else
1447 ssthresh = 0;
1448 metrics.rmx_ssthresh = ssthresh;
1449
1450 metrics.rmx_rtt = tp->t_srtt;
1451 metrics.rmx_rttvar = tp->t_rttvar;
1452 metrics.rmx_cwnd = tp->snd_cwnd;
1453 metrics.rmx_sendpipe = 0;
1454 metrics.rmx_recvpipe = 0;
1455
1456 tcp_hc_update(&inp->inp_inc, &metrics);
1457 }
1458
1459 /* free the reassembly queue, if any */
1460 tcp_reass_flush(tp);
1461
1462 #ifdef TCP_OFFLOAD
1463 /* Disconnect offload device, if any. */
1464 if (tp->t_flags & TF_TOE)
1465 tcp_offload_detach(tp);
1466 #endif
1467
1468 tcp_free_sackholes(tp);
1469
1470 #ifdef TCPPCAP
1471 /* Free the TCP PCAP queues. */
1472 tcp_pcap_drain(&(tp->t_inpkts));
1473 tcp_pcap_drain(&(tp->t_outpkts));
1474 #endif
1475
1476 /* Allow the CC algorithm to clean up after itself. */
1477 if (CC_ALGO(tp)->cb_destroy != NULL)
1478 CC_ALGO(tp)->cb_destroy(tp->ccv);
1479
1480 khelp_destroy_osd(tp->osd);
1481
1482 CC_ALGO(tp) = NULL;
1483 inp->inp_ppcb = NULL;
1484 if (tp->t_timers->tt_draincnt == 0) {
1485 /* We own the last reference on tcpcb, let's free it. */
1486 if (tp->t_fb->tfb_tcp_fb_fini)
1487 (*tp->t_fb->tfb_tcp_fb_fini)(tp);
1488 refcount_release(&tp->t_fb->tfb_refcnt);
1489 tp->t_inpcb = NULL;
1490 uma_zfree(V_tcpcb_zone, tp);
1491 released = in_pcbrele_wlocked(inp);
1492 KASSERT(!released, ("%s: inp %p should not have been released "
1493 "here", __func__, inp));
1494 }
1495 }
1496
1497 void
1498 tcp_timer_discard(void *ptp)
1499 {
1500 struct inpcb *inp;
1501 struct tcpcb *tp;
1502
1503 tp = (struct tcpcb *)ptp;
1504 CURVNET_SET(tp->t_vnet);
1505 INP_INFO_RLOCK(&V_tcbinfo);
1506 inp = tp->t_inpcb;
1507 KASSERT(inp != NULL, ("%s: tp %p tp->t_inpcb == NULL",
1508 __func__, tp));
1509 INP_WLOCK(inp);
1510 KASSERT((tp->t_timers->tt_flags & TT_STOPPED) != 0,
1511 ("%s: tcpcb has to be stopped here", __func__));
1512 tp->t_timers->tt_draincnt--;
1513 if (tp->t_timers->tt_draincnt == 0) {
1514 /* We own the last reference on this tcpcb, let's free it. */
1515 if (tp->t_fb->tfb_tcp_fb_fini)
1516 (*tp->t_fb->tfb_tcp_fb_fini)(tp);
1517 refcount_release(&tp->t_fb->tfb_refcnt);
1518 tp->t_inpcb = NULL;
1519 uma_zfree(V_tcpcb_zone, tp);
1520 if (in_pcbrele_wlocked(inp)) {
1521 INP_INFO_RUNLOCK(&V_tcbinfo);
1522 CURVNET_RESTORE();
1523 return;
1524 }
1525 }
1526 INP_WUNLOCK(inp);
1527 INP_INFO_RUNLOCK(&V_tcbinfo);
1528 CURVNET_RESTORE();
1529 }
1530
1531 /*
1532 * Attempt to close a TCP control block, marking it as dropped, and freeing
1533 * the socket if we hold the only reference.
1534 */
1535 struct tcpcb *
1536 tcp_close(struct tcpcb *tp)
1537 {
1538 struct inpcb *inp = tp->t_inpcb;
1539 struct socket *so;
1540
1541 INP_INFO_LOCK_ASSERT(&V_tcbinfo);
1542 INP_WLOCK_ASSERT(inp);
1543
1544 #ifdef TCP_OFFLOAD
1545 if (tp->t_state == TCPS_LISTEN)
1546 tcp_offload_listen_stop(tp);
1547 #endif
1548 #ifdef TCP_RFC7413
1549 /*
1550 * This releases the TFO pending counter resource for TFO listen
1551 * sockets as well as passively-created TFO sockets that transition
1552 * from SYN_RECEIVED to CLOSED.
1553 */
1554 if (tp->t_tfo_pending) {
1555 tcp_fastopen_decrement_counter(tp->t_tfo_pending);
1556 tp->t_tfo_pending = NULL;
1557 }
1558 #endif
1559 in_pcbdrop(inp);
1560 TCPSTAT_INC(tcps_closed);
1561 TCPSTATES_DEC(tp->t_state);
1562 KASSERT(inp->inp_socket != NULL, ("tcp_close: inp_socket NULL"));
1563 so = inp->inp_socket;
1564 soisdisconnected(so);
1565 if (inp->inp_flags & INP_SOCKREF) {
1566 KASSERT(so->so_state & SS_PROTOREF,
1567 ("tcp_close: !SS_PROTOREF"));
1568 inp->inp_flags &= ~INP_SOCKREF;
1569 INP_WUNLOCK(inp);
1570 ACCEPT_LOCK();
1571 SOCK_LOCK(so);
1572 so->so_state &= ~SS_PROTOREF;
1573 sofree(so);
1574 return (NULL);
1575 }
1576 return (tp);
1577 }
1578
1579 void
1580 tcp_drain(void)
1581 {
1582 VNET_ITERATOR_DECL(vnet_iter);
1583
1584 if (!do_tcpdrain)
1585 return;
1586
1587 VNET_LIST_RLOCK_NOSLEEP();
1588 VNET_FOREACH(vnet_iter) {
1589 CURVNET_SET(vnet_iter);
1590 struct inpcb *inpb;
1591 struct tcpcb *tcpb;
1592
1593 /*
1594 * Walk the tcpbs, if existing, and flush the reassembly queue,
1595 * if there is one...
1596 * XXX: The "Net/3" implementation doesn't imply that the TCP
1597 * reassembly queue should be flushed, but in a situation
1598 * where we're really low on mbufs, this is potentially
1599 * useful.
1600 */
1601 INP_INFO_WLOCK(&V_tcbinfo);
1602 LIST_FOREACH(inpb, V_tcbinfo.ipi_listhead, inp_list) {
1603 if (inpb->inp_flags & INP_TIMEWAIT)
1604 continue;
1605 INP_WLOCK(inpb);
1606 if ((tcpb = intotcpcb(inpb)) != NULL) {
1607 tcp_reass_flush(tcpb);
1608 tcp_clean_sackreport(tcpb);
1609 #ifdef TCPPCAP
1610 if (tcp_pcap_aggressive_free) {
1611 /* Free the TCP PCAP queues. */
1612 tcp_pcap_drain(&(tcpb->t_inpkts));
1613 tcp_pcap_drain(&(tcpb->t_outpkts));
1614 }
1615 #endif
1616 }
1617 INP_WUNLOCK(inpb);
1618 }
1619 INP_INFO_WUNLOCK(&V_tcbinfo);
1620 CURVNET_RESTORE();
1621 }
1622 VNET_LIST_RUNLOCK_NOSLEEP();
1623 }
1624
1625 /*
1626 * Notify a tcp user of an asynchronous error;
1627 * store error as soft error, but wake up user
1628 * (for now, won't do anything until can select for soft error).
1629 *
1630 * Do not wake up user since there currently is no mechanism for
1631 * reporting soft errors (yet - a kqueue filter may be added).
1632 */
1633 static struct inpcb *
1634 tcp_notify(struct inpcb *inp, int error)
1635 {
1636 struct tcpcb *tp;
1637
1638 INP_INFO_LOCK_ASSERT(&V_tcbinfo);
1639 INP_WLOCK_ASSERT(inp);
1640
1641 if ((inp->inp_flags & INP_TIMEWAIT) ||
1642 (inp->inp_flags & INP_DROPPED))
1643 return (inp);
1644
1645 tp = intotcpcb(inp);
1646 KASSERT(tp != NULL, ("tcp_notify: tp == NULL"));
1647
1648 /*
1649 * Ignore some errors if we are hooked up.
1650 * If connection hasn't completed, has retransmitted several times,
1651 * and receives a second error, give up now. This is better
1652 * than waiting a long time to establish a connection that
1653 * can never complete.
1654 */
1655 if (tp->t_state == TCPS_ESTABLISHED &&
1656 (error == EHOSTUNREACH || error == ENETUNREACH ||
1657 error == EHOSTDOWN)) {
1658 if (inp->inp_route.ro_rt) {
1659 RTFREE(inp->inp_route.ro_rt);
1660 inp->inp_route.ro_rt = (struct rtentry *)NULL;
1661 }
1662 return (inp);
1663 } else if (tp->t_state < TCPS_ESTABLISHED && tp->t_rxtshift > 3 &&
1664 tp->t_softerror) {
1665 tp = tcp_drop(tp, error);
1666 if (tp != NULL)
1667 return (inp);
1668 else
1669 return (NULL);
1670 } else {
1671 tp->t_softerror = error;
1672 return (inp);
1673 }
1674 #if 0
1675 wakeup( &so->so_timeo);
1676 sorwakeup(so);
1677 sowwakeup(so);
1678 #endif
1679 }
1680
1681 static int
1682 tcp_pcblist(SYSCTL_HANDLER_ARGS)
1683 {
1684 int error, i, m, n, pcb_count;
1685 struct inpcb *inp, **inp_list;
1686 inp_gen_t gencnt;
1687 struct xinpgen xig;
1688
1689 /*
1690 * The process of preparing the TCB list is too time-consuming and
1691 * resource-intensive to repeat twice on every request.
1692 */
1693 if (req->oldptr == NULL) {
1694 n = V_tcbinfo.ipi_count +
1695 counter_u64_fetch(V_tcps_states[TCPS_SYN_RECEIVED]);
1696 n += imax(n / 8, 10);
1697 req->oldidx = 2 * (sizeof xig) + n * sizeof(struct xtcpcb);
1698 return (0);
1699 }
1700
1701 if (req->newptr != NULL)
1702 return (EPERM);
1703
1704 /*
1705 * OK, now we're committed to doing something.
1706 */
1707 INP_LIST_RLOCK(&V_tcbinfo);
1708 gencnt = V_tcbinfo.ipi_gencnt;
1709 n = V_tcbinfo.ipi_count;
1710 INP_LIST_RUNLOCK(&V_tcbinfo);
1711
1712 m = counter_u64_fetch(V_tcps_states[TCPS_SYN_RECEIVED]);
1713
1714 error = sysctl_wire_old_buffer(req, 2 * (sizeof xig)
1715 + (n + m) * sizeof(struct xtcpcb));
1716 if (error != 0)
1717 return (error);
1718
1719 xig.xig_len = sizeof xig;
1720 xig.xig_count = n + m;
1721 xig.xig_gen = gencnt;
1722 xig.xig_sogen = so_gencnt;
1723 error = SYSCTL_OUT(req, &xig, sizeof xig);
1724 if (error)
1725 return (error);
1726
1727 error = syncache_pcblist(req, m, &pcb_count);
1728 if (error)
1729 return (error);
1730
1731 inp_list = malloc(n * sizeof *inp_list, M_TEMP, M_WAITOK);
1732
1733 INP_INFO_WLOCK(&V_tcbinfo);
1734 for (inp = LIST_FIRST(V_tcbinfo.ipi_listhead), i = 0;
1735 inp != NULL && i < n; inp = LIST_NEXT(inp, inp_list)) {
1736 INP_WLOCK(inp);
1737 if (inp->inp_gencnt <= gencnt) {
1738 /*
1739 * XXX: This use of cr_cansee(), introduced with
1740 * TCP state changes, is not quite right, but for
1741 * now, better than nothing.
1742 */
1743 if (inp->inp_flags & INP_TIMEWAIT) {
1744 if (intotw(inp) != NULL)
1745 error = cr_cansee(req->td->td_ucred,
1746 intotw(inp)->tw_cred);
1747 else
1748 error = EINVAL; /* Skip this inp. */
1749 } else
1750 error = cr_canseeinpcb(req->td->td_ucred, inp);
1751 if (error == 0) {
1752 in_pcbref(inp);
1753 inp_list[i++] = inp;
1754 }
1755 }
1756 INP_WUNLOCK(inp);
1757 }
1758 INP_INFO_WUNLOCK(&V_tcbinfo);
1759 n = i;
1760
1761 error = 0;
1762 for (i = 0; i < n; i++) {
1763 inp = inp_list[i];
1764 INP_RLOCK(inp);
1765 if (inp->inp_gencnt <= gencnt) {
1766 struct xtcpcb xt;
1767 void *inp_ppcb;
1768
1769 bzero(&xt, sizeof(xt));
1770 xt.xt_len = sizeof xt;
1771 /* XXX should avoid extra copy */
1772 bcopy(inp, &xt.xt_inp, sizeof *inp);
1773 inp_ppcb = inp->inp_ppcb;
1774 if (inp_ppcb == NULL)
1775 bzero((char *) &xt.xt_tp, sizeof xt.xt_tp);
1776 else if (inp->inp_flags & INP_TIMEWAIT) {
1777 bzero((char *) &xt.xt_tp, sizeof xt.xt_tp);
1778 xt.xt_tp.t_state = TCPS_TIME_WAIT;
1779 } else {
1780 bcopy(inp_ppcb, &xt.xt_tp, sizeof xt.xt_tp);
1781 if (xt.xt_tp.t_timers)
1782 tcp_timer_to_xtimer(&xt.xt_tp, xt.xt_tp.t_timers, &xt.xt_timer);
1783 }
1784 if (inp->inp_socket != NULL)
1785 sotoxsocket(inp->inp_socket, &xt.xt_socket);
1786 else {
1787 bzero(&xt.xt_socket, sizeof xt.xt_socket);
1788 xt.xt_socket.xso_protocol = IPPROTO_TCP;
1789 }
1790 xt.xt_inp.inp_gencnt = inp->inp_gencnt;
1791 INP_RUNLOCK(inp);
1792 error = SYSCTL_OUT(req, &xt, sizeof xt);
1793 } else
1794 INP_RUNLOCK(inp);
1795 }
1796 INP_INFO_RLOCK(&V_tcbinfo);
1797 for (i = 0; i < n; i++) {
1798 inp = inp_list[i];
1799 INP_RLOCK(inp);
1800 if (!in_pcbrele_rlocked(inp))
1801 INP_RUNLOCK(inp);
1802 }
1803 INP_INFO_RUNLOCK(&V_tcbinfo);
1804
1805 if (!error) {
1806 /*
1807 * Give the user an updated idea of our state.
1808 * If the generation differs from what we told
1809 * her before, she knows that something happened
1810 * while we were processing this request, and it
1811 * might be necessary to retry.
1812 */
1813 INP_LIST_RLOCK(&V_tcbinfo);
1814 xig.xig_gen = V_tcbinfo.ipi_gencnt;
1815 xig.xig_sogen = so_gencnt;
1816 xig.xig_count = V_tcbinfo.ipi_count + pcb_count;
1817 INP_LIST_RUNLOCK(&V_tcbinfo);
1818 error = SYSCTL_OUT(req, &xig, sizeof xig);
1819 }
1820 free(inp_list, M_TEMP);
1821 return (error);
1822 }
1823
1824 SYSCTL_PROC(_net_inet_tcp, TCPCTL_PCBLIST, pcblist,
1825 CTLTYPE_OPAQUE | CTLFLAG_RD, NULL, 0,
1826 tcp_pcblist, "S,xtcpcb", "List of active TCP connections");
1827
1828 #ifdef INET
1829 static int
1830 tcp_getcred(SYSCTL_HANDLER_ARGS)
1831 {
1832 struct xucred xuc;
1833 struct sockaddr_in addrs[2];
1834 struct inpcb *inp;
1835 int error;
1836
1837 error = priv_check(req->td, PRIV_NETINET_GETCRED);
1838 if (error)
1839 return (error);
1840 error = SYSCTL_IN(req, addrs, sizeof(addrs));
1841 if (error)
1842 return (error);
1843 inp = in_pcblookup(&V_tcbinfo, addrs[1].sin_addr, addrs[1].sin_port,
1844 addrs[0].sin_addr, addrs[0].sin_port, INPLOOKUP_RLOCKPCB, NULL);
1845 if (inp != NULL) {
1846 if (inp->inp_socket == NULL)
1847 error = ENOENT;
1848 if (error == 0)
1849 error = cr_canseeinpcb(req->td->td_ucred, inp);
1850 if (error == 0)
1851 cru2x(inp->inp_cred, &xuc);
1852 INP_RUNLOCK(inp);
1853 } else
1854 error = ENOENT;
1855 if (error == 0)
1856 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred));
1857 return (error);
1858 }
1859
1860 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, getcred,
1861 CTLTYPE_OPAQUE|CTLFLAG_RW|CTLFLAG_PRISON, 0, 0,
1862 tcp_getcred, "S,xucred", "Get the xucred of a TCP connection");
1863 #endif /* INET */
1864
1865 #ifdef INET6
1866 static int
1867 tcp6_getcred(SYSCTL_HANDLER_ARGS)
1868 {
1869 struct xucred xuc;
1870 struct sockaddr_in6 addrs[2];
1871 struct inpcb *inp;
1872 int error;
1873 #ifdef INET
1874 int mapped = 0;
1875 #endif
1876
1877 error = priv_check(req->td, PRIV_NETINET_GETCRED);
1878 if (error)
1879 return (error);
1880 error = SYSCTL_IN(req, addrs, sizeof(addrs));
1881 if (error)
1882 return (error);
1883 if ((error = sa6_embedscope(&addrs[0], V_ip6_use_defzone)) != 0 ||
1884 (error = sa6_embedscope(&addrs[1], V_ip6_use_defzone)) != 0) {
1885 return (error);
1886 }
1887 if (IN6_IS_ADDR_V4MAPPED(&addrs[0].sin6_addr)) {
1888 #ifdef INET
1889 if (IN6_IS_ADDR_V4MAPPED(&addrs[1].sin6_addr))
1890 mapped = 1;
1891 else
1892 #endif
1893 return (EINVAL);
1894 }
1895
1896 #ifdef INET
1897 if (mapped == 1)
1898 inp = in_pcblookup(&V_tcbinfo,
1899 *(struct in_addr *)&addrs[1].sin6_addr.s6_addr[12],
1900 addrs[1].sin6_port,
1901 *(struct in_addr *)&addrs[0].sin6_addr.s6_addr[12],
1902 addrs[0].sin6_port, INPLOOKUP_RLOCKPCB, NULL);
1903 else
1904 #endif
1905 inp = in6_pcblookup(&V_tcbinfo,
1906 &addrs[1].sin6_addr, addrs[1].sin6_port,
1907 &addrs[0].sin6_addr, addrs[0].sin6_port,
1908 INPLOOKUP_RLOCKPCB, NULL);
1909 if (inp != NULL) {
1910 if (inp->inp_socket == NULL)
1911 error = ENOENT;
1912 if (error == 0)
1913 error = cr_canseeinpcb(req->td->td_ucred, inp);
1914 if (error == 0)
1915 cru2x(inp->inp_cred, &xuc);
1916 INP_RUNLOCK(inp);
1917 } else
1918 error = ENOENT;
1919 if (error == 0)
1920 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred));
1921 return (error);
1922 }
1923
1924 SYSCTL_PROC(_net_inet6_tcp6, OID_AUTO, getcred,
1925 CTLTYPE_OPAQUE|CTLFLAG_RW|CTLFLAG_PRISON, 0, 0,
1926 tcp6_getcred, "S,xucred", "Get the xucred of a TCP6 connection");
1927 #endif /* INET6 */
1928
1929
1930 #ifdef INET
1931 void
1932 tcp_ctlinput(int cmd, struct sockaddr *sa, void *vip)
1933 {
1934 struct ip *ip = vip;
1935 struct tcphdr *th;
1936 struct in_addr faddr;
1937 struct inpcb *inp;
1938 struct tcpcb *tp;
1939 struct inpcb *(*notify)(struct inpcb *, int) = tcp_notify;
1940 struct icmp *icp;
1941 struct in_conninfo inc;
1942 tcp_seq icmp_tcp_seq;
1943 int mtu;
1944
1945 faddr = ((struct sockaddr_in *)sa)->sin_addr;
1946 if (sa->sa_family != AF_INET || faddr.s_addr == INADDR_ANY)
1947 return;
1948
1949 if (cmd == PRC_MSGSIZE)
1950 notify = tcp_mtudisc_notify;
1951 else if (V_icmp_may_rst && (cmd == PRC_UNREACH_ADMIN_PROHIB ||
1952 cmd == PRC_UNREACH_PORT || cmd == PRC_TIMXCEED_INTRANS) && ip)
1953 notify = tcp_drop_syn_sent;
1954
1955 /*
1956 * Hostdead is ugly because it goes linearly through all PCBs.
1957 * XXX: We never get this from ICMP, otherwise it makes an
1958 * excellent DoS attack on machines with many connections.
1959 */
1960 else if (cmd == PRC_HOSTDEAD)
1961 ip = NULL;
1962 else if ((unsigned)cmd >= PRC_NCMDS || inetctlerrmap[cmd] == 0)
1963 return;
1964
1965 if (ip == NULL) {
1966 in_pcbnotifyall(&V_tcbinfo, faddr, inetctlerrmap[cmd], notify);
1967 return;
1968 }
1969
1970 icp = (struct icmp *)((caddr_t)ip - offsetof(struct icmp, icmp_ip));
1971 th = (struct tcphdr *)((caddr_t)ip + (ip->ip_hl << 2));
1972 INP_INFO_RLOCK(&V_tcbinfo);
1973 inp = in_pcblookup(&V_tcbinfo, faddr, th->th_dport, ip->ip_src,
1974 th->th_sport, INPLOOKUP_WLOCKPCB, NULL);
1975 if (inp != NULL && PRC_IS_REDIRECT(cmd)) {
1976 /* signal EHOSTDOWN, as it flushes the cached route */
1977 inp = (*notify)(inp, EHOSTDOWN);
1978 if (inp != NULL)
1979 INP_WUNLOCK(inp);
1980 } else if (inp != NULL) {
1981 if (!(inp->inp_flags & INP_TIMEWAIT) &&
1982 !(inp->inp_flags & INP_DROPPED) &&
1983 !(inp->inp_socket == NULL)) {
1984 icmp_tcp_seq = ntohl(th->th_seq);
1985 tp = intotcpcb(inp);
1986 if (SEQ_GEQ(icmp_tcp_seq, tp->snd_una) &&
1987 SEQ_LT(icmp_tcp_seq, tp->snd_max)) {
1988 if (cmd == PRC_MSGSIZE) {
1989 /*
1990 * MTU discovery:
1991 * If we got a needfrag set the MTU
1992 * in the route to the suggested new
1993 * value (if given) and then notify.
1994 */
1995 mtu = ntohs(icp->icmp_nextmtu);
1996 /*
1997 * If no alternative MTU was
1998 * proposed, try the next smaller
1999 * one.
2000 */
2001 if (!mtu)
2002 mtu = ip_next_mtu(
2003 ntohs(ip->ip_len), 1);
2004 if (mtu < V_tcp_minmss +
2005 sizeof(struct tcpiphdr))
2006 mtu = V_tcp_minmss +
2007 sizeof(struct tcpiphdr);
2008 /*
2009 * Only process the offered MTU if it
2010 * is smaller than the current one.
2011 */
2012 if (mtu < tp->t_maxseg +
2013 sizeof(struct tcpiphdr)) {
2014 bzero(&inc, sizeof(inc));
2015 inc.inc_faddr = faddr;
2016 inc.inc_fibnum =
2017 inp->inp_inc.inc_fibnum;
2018 tcp_hc_updatemtu(&inc, mtu);
2019 tcp_mtudisc(inp, mtu);
2020 }
2021 } else
2022 inp = (*notify)(inp,
2023 inetctlerrmap[cmd]);
2024 }
2025 }
2026 if (inp != NULL)
2027 INP_WUNLOCK(inp);
2028 } else {
2029 bzero(&inc, sizeof(inc));
2030 inc.inc_fport = th->th_dport;
2031 inc.inc_lport = th->th_sport;
2032 inc.inc_faddr = faddr;
2033 inc.inc_laddr = ip->ip_src;
2034 syncache_unreach(&inc, th);
2035 }
2036 INP_INFO_RUNLOCK(&V_tcbinfo);
2037 }
2038 #endif /* INET */
2039
2040 #ifdef INET6
2041 void
2042 tcp6_ctlinput(int cmd, struct sockaddr *sa, void *d)
2043 {
2044 struct in6_addr *dst;
2045 struct tcphdr *th;
2046 struct inpcb *(*notify)(struct inpcb *, int) = tcp_notify;
2047 struct ip6_hdr *ip6;
2048 struct mbuf *m;
2049 struct inpcb *inp;
2050 struct tcpcb *tp;
2051 struct icmp6_hdr *icmp6;
2052 struct ip6ctlparam *ip6cp = NULL;
2053 const struct sockaddr_in6 *sa6_src = NULL;
2054 struct in_conninfo inc;
2055 tcp_seq icmp_tcp_seq;
2056 unsigned int mtu;
2057 unsigned int off;
2058
2059
2060 if (sa->sa_family != AF_INET6 ||
2061 sa->sa_len != sizeof(struct sockaddr_in6))
2062 return;
2063
2064 /* if the parameter is from icmp6, decode it. */
2065 if (d != NULL) {
2066 ip6cp = (struct ip6ctlparam *)d;
2067 icmp6 = ip6cp->ip6c_icmp6;
2068 m = ip6cp->ip6c_m;
2069 ip6 = ip6cp->ip6c_ip6;
2070 off = ip6cp->ip6c_off;
2071 sa6_src = ip6cp->ip6c_src;
2072 dst = ip6cp->ip6c_finaldst;
2073 } else {
2074 m = NULL;
2075 ip6 = NULL;
2076 off = 0; /* fool gcc */
2077 sa6_src = &sa6_any;
2078 dst = NULL;
2079 }
2080
2081 if (cmd == PRC_MSGSIZE)
2082 notify = tcp_mtudisc_notify;
2083 else if (V_icmp_may_rst && (cmd == PRC_UNREACH_ADMIN_PROHIB ||
2084 cmd == PRC_UNREACH_PORT || cmd == PRC_TIMXCEED_INTRANS) &&
2085 ip6 != NULL)
2086 notify = tcp_drop_syn_sent;
2087
2088 /*
2089 * Hostdead is ugly because it goes linearly through all PCBs.
2090 * XXX: We never get this from ICMP, otherwise it makes an
2091 * excellent DoS attack on machines with many connections.
2092 */
2093 else if (cmd == PRC_HOSTDEAD)
2094 ip6 = NULL;
2095 else if ((unsigned)cmd >= PRC_NCMDS || inet6ctlerrmap[cmd] == 0)
2096 return;
2097
2098 if (ip6 == NULL) {
2099 in6_pcbnotify(&V_tcbinfo, sa, 0,
2100 (const struct sockaddr *)sa6_src,
2101 0, cmd, NULL, notify);
2102 return;
2103 }
2104
2105 /* Check if we can safely get the ports from the tcp hdr */
2106 if (m == NULL ||
2107 (m->m_pkthdr.len <
2108 (int32_t) (off + offsetof(struct tcphdr, th_seq)))) {
2109 return;
2110 }
2111
2112 th = (struct tcphdr *) mtodo(ip6cp->ip6c_m, ip6cp->ip6c_off);
2113 INP_INFO_RLOCK(&V_tcbinfo);
2114 inp = in6_pcblookup(&V_tcbinfo, &ip6->ip6_dst, th->th_dport,
2115 &ip6->ip6_src, th->th_sport, INPLOOKUP_WLOCKPCB, NULL);
2116 if (inp != NULL && PRC_IS_REDIRECT(cmd)) {
2117 /* signal EHOSTDOWN, as it flushes the cached route */
2118 inp = (*notify)(inp, EHOSTDOWN);
2119 if (inp != NULL)
2120 INP_WUNLOCK(inp);
2121 } else if (inp != NULL) {
2122 if (!(inp->inp_flags & INP_TIMEWAIT) &&
2123 !(inp->inp_flags & INP_DROPPED) &&
2124 !(inp->inp_socket == NULL)) {
2125 icmp_tcp_seq = ntohl(th->th_seq);
2126 tp = intotcpcb(inp);
2127 if (SEQ_GEQ(icmp_tcp_seq, tp->snd_una) &&
2128 SEQ_LT(icmp_tcp_seq, tp->snd_max)) {
2129 if (cmd == PRC_MSGSIZE) {
2130 /*
2131 * MTU discovery:
2132 * If we got a needfrag set the MTU
2133 * in the route to the suggested new
2134 * value (if given) and then notify.
2135 */
2136 mtu = ntohl(icmp6->icmp6_mtu);
2137 /*
2138 * If no alternative MTU was
2139 * proposed, or the proposed
2140 * MTU was too small, set to
2141 * the min.
2142 */
2143 if (mtu < IPV6_MMTU)
2144 mtu = IPV6_MMTU - 8;
2145
2146
2147 bzero(&inc, sizeof(inc));
2148 inc.inc_fibnum = M_GETFIB(m);
2149 inc.inc_flags |= INC_ISIPV6;
2150 inc.inc6_faddr = *dst;
2151 if (in6_setscope(&inc.inc6_faddr,
2152 m->m_pkthdr.rcvif, NULL))
2153 goto unlock_inp;
2154
2155 /*
2156 * Only process the offered MTU if it
2157 * is smaller than the current one.
2158 */
2159 if (mtu < tp->t_maxseg +
2160 (sizeof (*th) + sizeof (*ip6))) {
2161 tcp_hc_updatemtu(&inc, mtu);
2162 tcp_mtudisc(inp, mtu);
2163 ICMP6STAT_INC(icp6s_pmtuchg);
2164 }
2165 } else
2166 inp = (*notify)(inp,
2167 inet6ctlerrmap[cmd]);
2168 }
2169 }
2170 unlock_inp:
2171 if (inp != NULL)
2172 INP_WUNLOCK(inp);
2173 } else {
2174 bzero(&inc, sizeof(inc));
2175 inc.inc_fibnum = M_GETFIB(m);
2176 inc.inc_flags |= INC_ISIPV6;
2177 inc.inc_fport = th->th_dport;
2178 inc.inc_lport = th->th_sport;
2179 inc.inc6_faddr = *dst;
2180 inc.inc6_laddr = ip6->ip6_src;
2181 syncache_unreach(&inc, th);
2182 }
2183 INP_INFO_RUNLOCK(&V_tcbinfo);
2184 }
2185 #endif /* INET6 */
2186
2187
2188 /*
2189 * Following is where TCP initial sequence number generation occurs.
2190 *
2191 * There are two places where we must use initial sequence numbers:
2192 * 1. In SYN-ACK packets.
2193 * 2. In SYN packets.
2194 *
2195 * All ISNs for SYN-ACK packets are generated by the syncache. See
2196 * tcp_syncache.c for details.
2197 *
2198 * The ISNs in SYN packets must be monotonic; TIME_WAIT recycling
2199 * depends on this property. In addition, these ISNs should be
2200 * unguessable so as to prevent connection hijacking. To satisfy
2201 * the requirements of this situation, the algorithm outlined in
2202 * RFC 1948 is used, with only small modifications.
2203 *
2204 * Implementation details:
2205 *
2206 * Time is based off the system timer, and is corrected so that it
2207 * increases by one megabyte per second. This allows for proper
2208 * recycling on high speed LANs while still leaving over an hour
2209 * before rollover.
2210 *
2211 * As reading the *exact* system time is too expensive to be done
2212 * whenever setting up a TCP connection, we increment the time
2213 * offset in two ways. First, a small random positive increment
2214 * is added to isn_offset for each connection that is set up.
2215 * Second, the function tcp_isn_tick fires once per clock tick
2216 * and increments isn_offset as necessary so that sequence numbers
2217 * are incremented at approximately ISN_BYTES_PER_SECOND. The
2218 * random positive increments serve only to ensure that the same
2219 * exact sequence number is never sent out twice (as could otherwise
2220 * happen when a port is recycled in less than the system tick
2221 * interval.)
2222 *
2223 * net.inet.tcp.isn_reseed_interval controls the number of seconds
2224 * between seeding of isn_secret. This is normally set to zero,
2225 * as reseeding should not be necessary.
2226 *
2227 * Locking of the global variables isn_secret, isn_last_reseed, isn_offset,
2228 * isn_offset_old, and isn_ctx is performed using the TCP pcbinfo lock. In
2229 * general, this means holding an exclusive (write) lock.
2230 */
2231
2232 #define ISN_BYTES_PER_SECOND 1048576
2233 #define ISN_STATIC_INCREMENT 4096
2234 #define ISN_RANDOM_INCREMENT (4096 - 1)
2235
2236 static VNET_DEFINE(u_char, isn_secret[32]);
2237 static VNET_DEFINE(int, isn_last);
2238 static VNET_DEFINE(int, isn_last_reseed);
2239 static VNET_DEFINE(u_int32_t, isn_offset);
2240 static VNET_DEFINE(u_int32_t, isn_offset_old);
2241
2242 #define V_isn_secret VNET(isn_secret)
2243 #define V_isn_last VNET(isn_last)
2244 #define V_isn_last_reseed VNET(isn_last_reseed)
2245 #define V_isn_offset VNET(isn_offset)
2246 #define V_isn_offset_old VNET(isn_offset_old)
2247
2248 tcp_seq
2249 tcp_new_isn(struct tcpcb *tp)
2250 {
2251 MD5_CTX isn_ctx;
2252 u_int32_t md5_buffer[4];
2253 tcp_seq new_isn;
2254 u_int32_t projected_offset;
2255
2256 INP_WLOCK_ASSERT(tp->t_inpcb);
2257
2258 ISN_LOCK();
2259 /* Seed if this is the first use, reseed if requested. */
2260 if ((V_isn_last_reseed == 0) || ((V_tcp_isn_reseed_interval > 0) &&
2261 (((u_int)V_isn_last_reseed + (u_int)V_tcp_isn_reseed_interval*hz)
2262 < (u_int)ticks))) {
2263 read_random(&V_isn_secret, sizeof(V_isn_secret));
2264 V_isn_last_reseed = ticks;
2265 }
2266
2267 /* Compute the md5 hash and return the ISN. */
2268 MD5Init(&isn_ctx);
2269 MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->inp_fport, sizeof(u_short));
2270 MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->inp_lport, sizeof(u_short));
2271 #ifdef INET6
2272 if ((tp->t_inpcb->inp_vflag & INP_IPV6) != 0) {
2273 MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->in6p_faddr,
2274 sizeof(struct in6_addr));
2275 MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->in6p_laddr,
2276 sizeof(struct in6_addr));
2277 } else
2278 #endif
2279 {
2280 MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->inp_faddr,
2281 sizeof(struct in_addr));
2282 MD5Update(&isn_ctx, (u_char *) &tp->t_inpcb->inp_laddr,
2283 sizeof(struct in_addr));
2284 }
2285 MD5Update(&isn_ctx, (u_char *) &V_isn_secret, sizeof(V_isn_secret));
2286 MD5Final((u_char *) &md5_buffer, &isn_ctx);
2287 new_isn = (tcp_seq) md5_buffer[0];
2288 V_isn_offset += ISN_STATIC_INCREMENT +
2289 (arc4random() & ISN_RANDOM_INCREMENT);
2290 if (ticks != V_isn_last) {
2291 projected_offset = V_isn_offset_old +
2292 ISN_BYTES_PER_SECOND / hz * (ticks - V_isn_last);
2293 if (SEQ_GT(projected_offset, V_isn_offset))
2294 V_isn_offset = projected_offset;
2295 V_isn_offset_old = V_isn_offset;
2296 V_isn_last = ticks;
2297 }
2298 new_isn += V_isn_offset;
2299 ISN_UNLOCK();
2300 return (new_isn);
2301 }
2302
2303 /*
2304 * When a specific ICMP unreachable message is received and the
2305 * connection state is SYN-SENT, drop the connection. This behavior
2306 * is controlled by the icmp_may_rst sysctl.
2307 */
2308 struct inpcb *
2309 tcp_drop_syn_sent(struct inpcb *inp, int errno)
2310 {
2311 struct tcpcb *tp;
2312
2313 INP_INFO_RLOCK_ASSERT(&V_tcbinfo);
2314 INP_WLOCK_ASSERT(inp);
2315
2316 if ((inp->inp_flags & INP_TIMEWAIT) ||
2317 (inp->inp_flags & INP_DROPPED))
2318 return (inp);
2319
2320 tp = intotcpcb(inp);
2321 if (tp->t_state != TCPS_SYN_SENT)
2322 return (inp);
2323
2324 tp = tcp_drop(tp, errno);
2325 if (tp != NULL)
2326 return (inp);
2327 else
2328 return (NULL);
2329 }
2330
2331 /*
2332 * When `need fragmentation' ICMP is received, update our idea of the MSS
2333 * based on the new value. Also nudge TCP to send something, since we
2334 * know the packet we just sent was dropped.
2335 * This duplicates some code in the tcp_mss() function in tcp_input.c.
2336 */
2337 static struct inpcb *
2338 tcp_mtudisc_notify(struct inpcb *inp, int error)
2339 {
2340
2341 tcp_mtudisc(inp, -1);
2342 return (inp);
2343 }
2344
2345 static void
2346 tcp_mtudisc(struct inpcb *inp, int mtuoffer)
2347 {
2348 struct tcpcb *tp;
2349 struct socket *so;
2350
2351 INP_WLOCK_ASSERT(inp);
2352 if ((inp->inp_flags & INP_TIMEWAIT) ||
2353 (inp->inp_flags & INP_DROPPED))
2354 return;
2355
2356 tp = intotcpcb(inp);
2357 KASSERT(tp != NULL, ("tcp_mtudisc: tp == NULL"));
2358
2359 tcp_mss_update(tp, -1, mtuoffer, NULL, NULL);
2360
2361 so = inp->inp_socket;
2362 SOCKBUF_LOCK(&so->so_snd);
2363 /* If the mss is larger than the socket buffer, decrease the mss. */
2364 if (so->so_snd.sb_hiwat < tp->t_maxseg)
2365 tp->t_maxseg = so->so_snd.sb_hiwat;
2366 SOCKBUF_UNLOCK(&so->so_snd);
2367
2368 TCPSTAT_INC(tcps_mturesent);
2369 tp->t_rtttime = 0;
2370 tp->snd_nxt = tp->snd_una;
2371 tcp_free_sackholes(tp);
2372 tp->snd_recover = tp->snd_max;
2373 if (tp->t_flags & TF_SACK_PERMIT)
2374 EXIT_FASTRECOVERY(tp->t_flags);
2375 tp->t_fb->tfb_tcp_output(tp);
2376 }
2377
2378 #ifdef INET
2379 /*
2380 * Look-up the routing entry to the peer of this inpcb. If no route
2381 * is found and it cannot be allocated, then return 0. This routine
2382 * is called by TCP routines that access the rmx structure and by
2383 * tcp_mss_update to get the peer/interface MTU.
2384 */
2385 u_long
2386 tcp_maxmtu(struct in_conninfo *inc, struct tcp_ifcap *cap)
2387 {
2388 struct nhop4_extended nh4;
2389 struct ifnet *ifp;
2390 u_long maxmtu = 0;
2391
2392 KASSERT(inc != NULL, ("tcp_maxmtu with NULL in_conninfo pointer"));
2393
2394 if (inc->inc_faddr.s_addr != INADDR_ANY) {
2395
2396 if (fib4_lookup_nh_ext(inc->inc_fibnum, inc->inc_faddr,
2397 NHR_REF, 0, &nh4) != 0)
2398 return (0);
2399
2400 ifp = nh4.nh_ifp;
2401 maxmtu = nh4.nh_mtu;
2402
2403 /* Report additional interface capabilities. */
2404 if (cap != NULL) {
2405 if (ifp->if_capenable & IFCAP_TSO4 &&
2406 ifp->if_hwassist & CSUM_TSO) {
2407 cap->ifcap |= CSUM_TSO;
2408 cap->tsomax = ifp->if_hw_tsomax;
2409 cap->tsomaxsegcount = ifp->if_hw_tsomaxsegcount;
2410 cap->tsomaxsegsize = ifp->if_hw_tsomaxsegsize;
2411 }
2412 }
2413 fib4_free_nh_ext(inc->inc_fibnum, &nh4);
2414 }
2415 return (maxmtu);
2416 }
2417 #endif /* INET */
2418
2419 #ifdef INET6
2420 u_long
2421 tcp_maxmtu6(struct in_conninfo *inc, struct tcp_ifcap *cap)
2422 {
2423 struct nhop6_extended nh6;
2424 struct in6_addr dst6;
2425 uint32_t scopeid;
2426 struct ifnet *ifp;
2427 u_long maxmtu = 0;
2428
2429 KASSERT(inc != NULL, ("tcp_maxmtu6 with NULL in_conninfo pointer"));
2430
2431 if (!IN6_IS_ADDR_UNSPECIFIED(&inc->inc6_faddr)) {
2432 in6_splitscope(&inc->inc6_faddr, &dst6, &scopeid);
2433 if (fib6_lookup_nh_ext(inc->inc_fibnum, &dst6, scopeid, 0,
2434 0, &nh6) != 0)
2435 return (0);
2436
2437 ifp = nh6.nh_ifp;
2438 maxmtu = nh6.nh_mtu;
2439
2440 /* Report additional interface capabilities. */
2441 if (cap != NULL) {
2442 if (ifp->if_capenable & IFCAP_TSO6 &&
2443 ifp->if_hwassist & CSUM_TSO) {
2444 cap->ifcap |= CSUM_TSO;
2445 cap->tsomax = ifp->if_hw_tsomax;
2446 cap->tsomaxsegcount = ifp->if_hw_tsomaxsegcount;
2447 cap->tsomaxsegsize = ifp->if_hw_tsomaxsegsize;
2448 }
2449 }
2450 fib6_free_nh_ext(inc->inc_fibnum, &nh6);
2451 }
2452
2453 return (maxmtu);
2454 }
2455 #endif /* INET6 */
2456
2457 /*
2458 * Calculate effective SMSS per RFC5681 definition for a given TCP
2459 * connection at its current state, taking into account SACK and etc.
2460 */
2461 u_int
2462 tcp_maxseg(const struct tcpcb *tp)
2463 {
2464 u_int optlen;
2465
2466 if (tp->t_flags & TF_NOOPT)
2467 return (tp->t_maxseg);
2468
2469 /*
2470 * Here we have a simplified code from tcp_addoptions(),
2471 * without a proper loop, and having most of paddings hardcoded.
2472 * We might make mistakes with padding here in some edge cases,
2473 * but this is harmless, since result of tcp_maxseg() is used
2474 * only in cwnd and ssthresh estimations.
2475 */
2476 #define PAD(len) ((((len) / 4) + !!((len) % 4)) * 4)
2477 if (TCPS_HAVEESTABLISHED(tp->t_state)) {
2478 if (tp->t_flags & TF_RCVD_TSTMP)
2479 optlen = TCPOLEN_TSTAMP_APPA;
2480 else
2481 optlen = 0;
2482 #ifdef TCP_SIGNATURE
2483 if (tp->t_flags & TF_SIGNATURE)
2484 optlen += PAD(TCPOLEN_SIGNATURE);
2485 #endif
2486 if ((tp->t_flags & TF_SACK_PERMIT) && tp->rcv_numsacks > 0) {
2487 optlen += TCPOLEN_SACKHDR;
2488 optlen += tp->rcv_numsacks * TCPOLEN_SACK;
2489 optlen = PAD(optlen);
2490 }
2491 } else {
2492 if (tp->t_flags & TF_REQ_TSTMP)
2493 optlen = TCPOLEN_TSTAMP_APPA;
2494 else
2495 optlen = PAD(TCPOLEN_MAXSEG);
2496 if (tp->t_flags & TF_REQ_SCALE)
2497 optlen += PAD(TCPOLEN_WINDOW);
2498 #ifdef TCP_SIGNATURE
2499 if (tp->t_flags & TF_SIGNATURE)
2500 optlen += PAD(TCPOLEN_SIGNATURE);
2501 #endif
2502 if (tp->t_flags & TF_SACK_PERMIT)
2503 optlen += PAD(TCPOLEN_SACK_PERMITTED);
2504 }
2505 #undef PAD
2506 optlen = min(optlen, TCP_MAXOLEN);
2507 return (tp->t_maxseg - optlen);
2508 }
2509
2510 #ifdef IPSEC
2511 /* compute ESP/AH header size for TCP, including outer IP header. */
2512 size_t
2513 ipsec_hdrsiz_tcp(struct tcpcb *tp)
2514 {
2515 struct inpcb *inp;
2516 struct mbuf *m;
2517 size_t hdrsiz;
2518 struct ip *ip;
2519 #ifdef INET6
2520 struct ip6_hdr *ip6;
2521 #endif
2522 struct tcphdr *th;
2523
2524 if ((tp == NULL) || ((inp = tp->t_inpcb) == NULL) ||
2525 (!key_havesp(IPSEC_DIR_OUTBOUND)))
2526 return (0);
2527 m = m_gethdr(M_NOWAIT, MT_DATA);
2528 if (!m)
2529 return (0);
2530
2531 #ifdef INET6
2532 if ((inp->inp_vflag & INP_IPV6) != 0) {
2533 ip6 = mtod(m, struct ip6_hdr *);
2534 th = (struct tcphdr *)(ip6 + 1);
2535 m->m_pkthdr.len = m->m_len =
2536 sizeof(struct ip6_hdr) + sizeof(struct tcphdr);
2537 tcpip_fillheaders(inp, ip6, th);
2538 hdrsiz = ipsec_hdrsiz(m, IPSEC_DIR_OUTBOUND, inp);
2539 } else
2540 #endif /* INET6 */
2541 {
2542 ip = mtod(m, struct ip *);
2543 th = (struct tcphdr *)(ip + 1);
2544 m->m_pkthdr.len = m->m_len = sizeof(struct tcpiphdr);
2545 tcpip_fillheaders(inp, ip, th);
2546 hdrsiz = ipsec_hdrsiz(m, IPSEC_DIR_OUTBOUND, inp);
2547 }
2548
2549 m_free(m);
2550 return (hdrsiz);
2551 }
2552 #endif /* IPSEC */
2553
2554 #ifdef TCP_SIGNATURE
2555 /*
2556 * Callback function invoked by m_apply() to digest TCP segment data
2557 * contained within an mbuf chain.
2558 */
2559 static int
2560 tcp_signature_apply(void *fstate, void *data, u_int len)
2561 {
2562
2563 MD5Update(fstate, (u_char *)data, len);
2564 return (0);
2565 }
2566
2567 /*
2568 * XXX The key is retrieved from the system's PF_KEY SADB, by keying a
2569 * search with the destination IP address, and a 'magic SPI' to be
2570 * determined by the application. This is hardcoded elsewhere to 1179
2571 */
2572 struct secasvar *
2573 tcp_get_sav(struct mbuf *m, u_int direction)
2574 {
2575 union sockaddr_union dst;
2576 struct secasvar *sav;
2577 struct ip *ip;
2578 #ifdef INET6
2579 struct ip6_hdr *ip6;
2580 char ip6buf[INET6_ADDRSTRLEN];
2581 #endif
2582
2583 /* Extract the destination from the IP header in the mbuf. */
2584 bzero(&dst, sizeof(union sockaddr_union));
2585 ip = mtod(m, struct ip *);
2586 #ifdef INET6
2587 ip6 = NULL; /* Make the compiler happy. */
2588 #endif
2589 switch (ip->ip_v) {
2590 #ifdef INET
2591 case IPVERSION:
2592 dst.sa.sa_len = sizeof(struct sockaddr_in);
2593 dst.sa.sa_family = AF_INET;
2594 dst.sin.sin_addr = (direction == IPSEC_DIR_INBOUND) ?
2595 ip->ip_src : ip->ip_dst;
2596 break;
2597 #endif
2598 #ifdef INET6
2599 case (IPV6_VERSION >> 4):
2600 ip6 = mtod(m, struct ip6_hdr *);
2601 dst.sa.sa_len = sizeof(struct sockaddr_in6);
2602 dst.sa.sa_family = AF_INET6;
2603 dst.sin6.sin6_addr = (direction == IPSEC_DIR_INBOUND) ?
2604 ip6->ip6_src : ip6->ip6_dst;
2605 break;
2606 #endif
2607 default:
2608 return (NULL);
2609 /* NOTREACHED */
2610 break;
2611 }
2612
2613 /* Look up an SADB entry which matches the address of the peer. */
2614 sav = KEY_ALLOCSA(&dst, IPPROTO_TCP, htonl(TCP_SIG_SPI));
2615 if (sav == NULL) {
2616 ipseclog((LOG_ERR, "%s: SADB lookup failed for %s\n", __func__,
2617 (ip->ip_v == IPVERSION) ? inet_ntoa(dst.sin.sin_addr) :
2618 #ifdef INET6
2619 (ip->ip_v == (IPV6_VERSION >> 4)) ?
2620 ip6_sprintf(ip6buf, &dst.sin6.sin6_addr) :
2621 #endif
2622 "(unsupported)"));
2623 }
2624
2625 return (sav);
2626 }
2627
2628 /*
2629 * Compute TCP-MD5 hash of a TCP segment. (RFC2385)
2630 *
2631 * Parameters:
2632 * m pointer to head of mbuf chain
2633 * len length of TCP segment data, excluding options
2634 * optlen length of TCP segment options
2635 * buf pointer to storage for computed MD5 digest
2636 * sav pointer to security assosiation
2637 *
2638 * We do this over ip, tcphdr, segment data, and the key in the SADB.
2639 * When called from tcp_input(), we can be sure that th_sum has been
2640 * zeroed out and verified already.
2641 *
2642 * Releases reference to SADB key before return.
2643 *
2644 * Return 0 if successful, otherwise return -1.
2645 *
2646 */
2647 int
2648 tcp_signature_do_compute(struct mbuf *m, int len, int optlen,
2649 u_char *buf, struct secasvar *sav)
2650 {
2651 #ifdef INET
2652 struct ippseudo ippseudo;
2653 #endif
2654 MD5_CTX ctx;
2655 int doff;
2656 struct ip *ip;
2657 #ifdef INET
2658 struct ipovly *ipovly;
2659 #endif
2660 struct tcphdr *th;
2661 #ifdef INET6
2662 struct ip6_hdr *ip6;
2663 struct in6_addr in6;
2664 uint32_t plen;
2665 uint16_t nhdr;
2666 #endif
2667 u_short savecsum;
2668
2669 KASSERT(m != NULL, ("NULL mbuf chain"));
2670 KASSERT(buf != NULL, ("NULL signature pointer"));
2671
2672 /* Extract the destination from the IP header in the mbuf. */
2673 ip = mtod(m, struct ip *);
2674 #ifdef INET6
2675 ip6 = NULL; /* Make the compiler happy. */
2676 #endif
2677
2678 MD5Init(&ctx);
2679 /*
2680 * Step 1: Update MD5 hash with IP(v6) pseudo-header.
2681 *
2682 * XXX The ippseudo header MUST be digested in network byte order,
2683 * or else we'll fail the regression test. Assume all fields we've
2684 * been doing arithmetic on have been in host byte order.
2685 * XXX One cannot depend on ipovly->ih_len here. When called from
2686 * tcp_output(), the underlying ip_len member has not yet been set.
2687 */
2688 switch (ip->ip_v) {
2689 #ifdef INET
2690 case IPVERSION:
2691 ipovly = (struct ipovly *)ip;
2692 ippseudo.ippseudo_src = ipovly->ih_src;
2693 ippseudo.ippseudo_dst = ipovly->ih_dst;
2694 ippseudo.ippseudo_pad = 0;
2695 ippseudo.ippseudo_p = IPPROTO_TCP;
2696 ippseudo.ippseudo_len = htons(len + sizeof(struct tcphdr) +
2697 optlen);
2698 MD5Update(&ctx, (char *)&ippseudo, sizeof(struct ippseudo));
2699
2700 th = (struct tcphdr *)((u_char *)ip + sizeof(struct ip));
2701 doff = sizeof(struct ip) + sizeof(struct tcphdr) + optlen;
2702 break;
2703 #endif
2704 #ifdef INET6
2705 /*
2706 * RFC 2385, 2.0 Proposal
2707 * For IPv6, the pseudo-header is as described in RFC 2460, namely the
2708 * 128-bit source IPv6 address, 128-bit destination IPv6 address, zero-
2709 * extended next header value (to form 32 bits), and 32-bit segment
2710 * length.
2711 * Note: Upper-Layer Packet Length comes before Next Header.
2712 */
2713 case (IPV6_VERSION >> 4):
2714 in6 = ip6->ip6_src;
2715 in6_clearscope(&in6);
2716 MD5Update(&ctx, (char *)&in6, sizeof(struct in6_addr));
2717 in6 = ip6->ip6_dst;
2718 in6_clearscope(&in6);
2719 MD5Update(&ctx, (char *)&in6, sizeof(struct in6_addr));
2720 plen = htonl(len + sizeof(struct tcphdr) + optlen);
2721 MD5Update(&ctx, (char *)&plen, sizeof(uint32_t));
2722 nhdr = 0;
2723 MD5Update(&ctx, (char *)&nhdr, sizeof(uint8_t));
2724 MD5Update(&ctx, (char *)&nhdr, sizeof(uint8_t));
2725 MD5Update(&ctx, (char *)&nhdr, sizeof(uint8_t));
2726 nhdr = IPPROTO_TCP;
2727 MD5Update(&ctx, (char *)&nhdr, sizeof(uint8_t));
2728
2729 th = (struct tcphdr *)((u_char *)ip6 + sizeof(struct ip6_hdr));
2730 doff = sizeof(struct ip6_hdr) + sizeof(struct tcphdr) + optlen;
2731 break;
2732 #endif
2733 default:
2734 KEY_FREESAV(&sav);
2735 return (-1);
2736 /* NOTREACHED */
2737 break;
2738 }
2739
2740
2741 /*
2742 * Step 2: Update MD5 hash with TCP header, excluding options.
2743 * The TCP checksum must be set to zero.
2744 */
2745 savecsum = th->th_sum;
2746 th->th_sum = 0;
2747 MD5Update(&ctx, (char *)th, sizeof(struct tcphdr));
2748 th->th_sum = savecsum;
2749
2750 /*
2751 * Step 3: Update MD5 hash with TCP segment data.
2752 * Use m_apply() to avoid an early m_pullup().
2753 */
2754 if (len > 0)
2755 m_apply(m, doff, len, tcp_signature_apply, &ctx);
2756
2757 /*
2758 * Step 4: Update MD5 hash with shared secret.
2759 */
2760 MD5Update(&ctx, sav->key_auth->key_data, _KEYLEN(sav->key_auth));
2761 MD5Final(buf, &ctx);
2762
2763 key_sa_recordxfer(sav, m);
2764 KEY_FREESAV(&sav);
2765 return (0);
2766 }
2767
2768 /*
2769 * Compute TCP-MD5 hash of a TCP segment. (RFC2385)
2770 *
2771 * Return 0 if successful, otherwise return -1.
2772 */
2773 int
2774 tcp_signature_compute(struct mbuf *m, int _unused, int len, int optlen,
2775 u_char *buf, u_int direction)
2776 {
2777 struct secasvar *sav;
2778
2779 if ((sav = tcp_get_sav(m, direction)) == NULL)
2780 return (-1);
2781
2782 return (tcp_signature_do_compute(m, len, optlen, buf, sav));
2783 }
2784
2785 /*
2786 * Verify the TCP-MD5 hash of a TCP segment. (RFC2385)
2787 *
2788 * Parameters:
2789 * m pointer to head of mbuf chain
2790 * len length of TCP segment data, excluding options
2791 * optlen length of TCP segment options
2792 * buf pointer to storage for computed MD5 digest
2793 * direction direction of flow (IPSEC_DIR_INBOUND or OUTBOUND)
2794 *
2795 * Return 1 if successful, otherwise return 0.
2796 */
2797 int
2798 tcp_signature_verify(struct mbuf *m, int off0, int tlen, int optlen,
2799 struct tcpopt *to, struct tcphdr *th, u_int tcpbflag)
2800 {
2801 char tmpdigest[TCP_SIGLEN];
2802
2803 if (tcp_sig_checksigs == 0)
2804 return (1);
2805 if ((tcpbflag & TF_SIGNATURE) == 0) {
2806 if ((to->to_flags & TOF_SIGNATURE) != 0) {
2807
2808 /*
2809 * If this socket is not expecting signature but
2810 * the segment contains signature just fail.
2811 */
2812 TCPSTAT_INC(tcps_sig_err_sigopt);
2813 TCPSTAT_INC(tcps_sig_rcvbadsig);
2814 return (0);
2815 }
2816
2817 /* Signature is not expected, and not present in segment. */
2818 return (1);
2819 }
2820
2821 /*
2822 * If this socket is expecting signature but the segment does not
2823 * contain any just fail.
2824 */
2825 if ((to->to_flags & TOF_SIGNATURE) == 0) {
2826 TCPSTAT_INC(tcps_sig_err_nosigopt);
2827 TCPSTAT_INC(tcps_sig_rcvbadsig);
2828 return (0);
2829 }
2830 if (tcp_signature_compute(m, off0, tlen, optlen, &tmpdigest[0],
2831 IPSEC_DIR_INBOUND) == -1) {
2832 TCPSTAT_INC(tcps_sig_err_buildsig);
2833 TCPSTAT_INC(tcps_sig_rcvbadsig);
2834 return (0);
2835 }
2836
2837 if (bcmp(to->to_signature, &tmpdigest[0], TCP_SIGLEN) != 0) {
2838 TCPSTAT_INC(tcps_sig_rcvbadsig);
2839 return (0);
2840 }
2841 TCPSTAT_INC(tcps_sig_rcvgoodsig);
2842 return (1);
2843 }
2844 #endif /* TCP_SIGNATURE */
2845
2846 static int
2847 sysctl_drop(SYSCTL_HANDLER_ARGS)
2848 {
2849 /* addrs[0] is a foreign socket, addrs[1] is a local one. */
2850 struct sockaddr_storage addrs[2];
2851 struct inpcb *inp;
2852 struct tcpcb *tp;
2853 struct tcptw *tw;
2854 struct sockaddr_in *fin, *lin;
2855 #ifdef INET6
2856 struct sockaddr_in6 *fin6, *lin6;
2857 #endif
2858 int error;
2859
2860 inp = NULL;
2861 fin = lin = NULL;
2862 #ifdef INET6
2863 fin6 = lin6 = NULL;
2864 #endif
2865 error = 0;
2866
2867 if (req->oldptr != NULL || req->oldlen != 0)
2868 return (EINVAL);
2869 if (req->newptr == NULL)
2870 return (EPERM);
2871 if (req->newlen < sizeof(addrs))
2872 return (ENOMEM);
2873 error = SYSCTL_IN(req, &addrs, sizeof(addrs));
2874 if (error)
2875 return (error);
2876
2877 switch (addrs[0].ss_family) {
2878 #ifdef INET6
2879 case AF_INET6:
2880 fin6 = (struct sockaddr_in6 *)&addrs[0];
2881 lin6 = (struct sockaddr_in6 *)&addrs[1];
2882 if (fin6->sin6_len != sizeof(struct sockaddr_in6) ||
2883 lin6->sin6_len != sizeof(struct sockaddr_in6))
2884 return (EINVAL);
2885 if (IN6_IS_ADDR_V4MAPPED(&fin6->sin6_addr)) {
2886 if (!IN6_IS_ADDR_V4MAPPED(&lin6->sin6_addr))
2887 return (EINVAL);
2888 in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[0]);
2889 in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[1]);
2890 fin = (struct sockaddr_in *)&addrs[0];
2891 lin = (struct sockaddr_in *)&addrs[1];
2892 break;
2893 }
2894 error = sa6_embedscope(fin6, V_ip6_use_defzone);
2895 if (error)
2896 return (error);
2897 error = sa6_embedscope(lin6, V_ip6_use_defzone);
2898 if (error)
2899 return (error);
2900 break;
2901 #endif
2902 #ifdef INET
2903 case AF_INET:
2904 fin = (struct sockaddr_in *)&addrs[0];
2905 lin = (struct sockaddr_in *)&addrs[1];
2906 if (fin->sin_len != sizeof(struct sockaddr_in) ||
2907 lin->sin_len != sizeof(struct sockaddr_in))
2908 return (EINVAL);
2909 break;
2910 #endif
2911 default:
2912 return (EINVAL);
2913 }
2914 INP_INFO_RLOCK(&V_tcbinfo);
2915 switch (addrs[0].ss_family) {
2916 #ifdef INET6
2917 case AF_INET6:
2918 inp = in6_pcblookup(&V_tcbinfo, &fin6->sin6_addr,
2919 fin6->sin6_port, &lin6->sin6_addr, lin6->sin6_port,
2920 INPLOOKUP_WLOCKPCB, NULL);
2921 break;
2922 #endif
2923 #ifdef INET
2924 case AF_INET:
2925 inp = in_pcblookup(&V_tcbinfo, fin->sin_addr, fin->sin_port,
2926 lin->sin_addr, lin->sin_port, INPLOOKUP_WLOCKPCB, NULL);
2927 break;
2928 #endif
2929 }
2930 if (inp != NULL) {
2931 if (inp->inp_flags & INP_TIMEWAIT) {
2932 /*
2933 * XXXRW: There currently exists a state where an
2934 * inpcb is present, but its timewait state has been
2935 * discarded. For now, don't allow dropping of this
2936 * type of inpcb.
2937 */
2938 tw = intotw(inp);
2939 if (tw != NULL)
2940 tcp_twclose(tw, 0);
2941 else
2942 INP_WUNLOCK(inp);
2943 } else if (!(inp->inp_flags & INP_DROPPED) &&
2944 !(inp->inp_socket->so_options & SO_ACCEPTCONN)) {
2945 tp = intotcpcb(inp);
2946 tp = tcp_drop(tp, ECONNABORTED);
2947 if (tp != NULL)
2948 INP_WUNLOCK(inp);
2949 } else
2950 INP_WUNLOCK(inp);
2951 } else
2952 error = ESRCH;
2953 INP_INFO_RUNLOCK(&V_tcbinfo);
2954 return (error);
2955 }
2956
2957 SYSCTL_PROC(_net_inet_tcp, TCPCTL_DROP, drop,
2958 CTLFLAG_VNET | CTLTYPE_STRUCT | CTLFLAG_WR | CTLFLAG_SKIP, NULL,
2959 0, sysctl_drop, "", "Drop TCP connection");
2960
2961 /*
2962 * Generate a standardized TCP log line for use throughout the
2963 * tcp subsystem. Memory allocation is done with M_NOWAIT to
2964 * allow use in the interrupt context.
2965 *
2966 * NB: The caller MUST free(s, M_TCPLOG) the returned string.
2967 * NB: The function may return NULL if memory allocation failed.
2968 *
2969 * Due to header inclusion and ordering limitations the struct ip
2970 * and ip6_hdr pointers have to be passed as void pointers.
2971 */
2972 char *
2973 tcp_log_vain(struct in_conninfo *inc, struct tcphdr *th, void *ip4hdr,
2974 const void *ip6hdr)
2975 {
2976
2977 /* Is logging enabled? */
2978 if (tcp_log_in_vain == 0)
2979 return (NULL);
2980
2981 return (tcp_log_addr(inc, th, ip4hdr, ip6hdr));
2982 }
2983
2984 char *
2985 tcp_log_addrs(struct in_conninfo *inc, struct tcphdr *th, void *ip4hdr,
2986 const void *ip6hdr)
2987 {
2988
2989 /* Is logging enabled? */
2990 if (tcp_log_debug == 0)
2991 return (NULL);
2992
2993 return (tcp_log_addr(inc, th, ip4hdr, ip6hdr));
2994 }
2995
2996 static char *
2997 tcp_log_addr(struct in_conninfo *inc, struct tcphdr *th, void *ip4hdr,
2998 const void *ip6hdr)
2999 {
3000 char *s, *sp;
3001 size_t size;
3002 struct ip *ip;
3003 #ifdef INET6
3004 const struct ip6_hdr *ip6;
3005
3006 ip6 = (const struct ip6_hdr *)ip6hdr;
3007 #endif /* INET6 */
3008 ip = (struct ip *)ip4hdr;
3009
3010 /*
3011 * The log line looks like this:
3012 * "TCP: [1.2.3.4]:50332 to [1.2.3.4]:80 tcpflags 0x2<SYN>"
3013 */
3014 size = sizeof("TCP: []:12345 to []:12345 tcpflags 0x2<>") +
3015 sizeof(PRINT_TH_FLAGS) + 1 +
3016 #ifdef INET6
3017 2 * INET6_ADDRSTRLEN;
3018 #else
3019 2 * INET_ADDRSTRLEN;
3020 #endif /* INET6 */
3021
3022 s = malloc(size, M_TCPLOG, M_ZERO|M_NOWAIT);
3023 if (s == NULL)
3024 return (NULL);
3025
3026 strcat(s, "TCP: [");
3027 sp = s + strlen(s);
3028
3029 if (inc && ((inc->inc_flags & INC_ISIPV6) == 0)) {
3030 inet_ntoa_r(inc->inc_faddr, sp);
3031 sp = s + strlen(s);
3032 sprintf(sp, "]:%i to [", ntohs(inc->inc_fport));
3033 sp = s + strlen(s);
3034 inet_ntoa_r(inc->inc_laddr, sp);
3035 sp = s + strlen(s);
3036 sprintf(sp, "]:%i", ntohs(inc->inc_lport));
3037 #ifdef INET6
3038 } else if (inc) {
3039 ip6_sprintf(sp, &inc->inc6_faddr);
3040 sp = s + strlen(s);
3041 sprintf(sp, "]:%i to [", ntohs(inc->inc_fport));
3042 sp = s + strlen(s);
3043 ip6_sprintf(sp, &inc->inc6_laddr);
3044 sp = s + strlen(s);
3045 sprintf(sp, "]:%i", ntohs(inc->inc_lport));
3046 } else if (ip6 && th) {
3047 ip6_sprintf(sp, &ip6->ip6_src);
3048 sp = s + strlen(s);
3049 sprintf(sp, "]:%i to [", ntohs(th->th_sport));
3050 sp = s + strlen(s);
3051 ip6_sprintf(sp, &ip6->ip6_dst);
3052 sp = s + strlen(s);
3053 sprintf(sp, "]:%i", ntohs(th->th_dport));
3054 #endif /* INET6 */
3055 #ifdef INET
3056 } else if (ip && th) {
3057 inet_ntoa_r(ip->ip_src, sp);
3058 sp = s + strlen(s);
3059 sprintf(sp, "]:%i to [", ntohs(th->th_sport));
3060 sp = s + strlen(s);
3061 inet_ntoa_r(ip->ip_dst, sp);
3062 sp = s + strlen(s);
3063 sprintf(sp, "]:%i", ntohs(th->th_dport));
3064 #endif /* INET */
3065 } else {
3066 free(s, M_TCPLOG);
3067 return (NULL);
3068 }
3069 sp = s + strlen(s);
3070 if (th)
3071 sprintf(sp, " tcpflags 0x%b", th->th_flags, PRINT_TH_FLAGS);
3072 if (*(s + size - 1) != '\0')
3073 panic("%s: string too long", __func__);
3074 return (s);
3075 }
3076
3077 /*
3078 * A subroutine which makes it easy to track TCP state changes with DTrace.
3079 * This function shouldn't be called for t_state initializations that don't
3080 * correspond to actual TCP state transitions.
3081 */
3082 void
3083 tcp_state_change(struct tcpcb *tp, int newstate)
3084 {
3085 #if defined(KDTRACE_HOOKS)
3086 int pstate = tp->t_state;
3087 #endif
3088
3089 TCPSTATES_DEC(tp->t_state);
3090 TCPSTATES_INC(newstate);
3091 tp->t_state = newstate;
3092 TCP_PROBE6(state__change, NULL, tp, NULL, tp, NULL, pstate);
3093 }
FreeBSD src