1 /*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1982, 1986, 1988, 1990, 1993, 1995
5 * The Regents of the University of California. All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
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.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 * SUCH DAMAGE.
30 */
31
32 #include <sys/cdefs.h>
33 #include "opt_inet.h"
34 #include "opt_inet6.h"
35 #include "opt_ipsec.h"
36 #include "opt_kern_tls.h"
37
38 #include <sys/param.h>
39 #include <sys/systm.h>
40 #include <sys/arb.h>
41 #include <sys/callout.h>
42 #include <sys/eventhandler.h>
43 #ifdef TCP_HHOOK
44 #include <sys/hhook.h>
45 #endif
46 #include <sys/kernel.h>
47 #ifdef TCP_HHOOK
48 #include <sys/khelp.h>
49 #endif
50 #ifdef KERN_TLS
51 #include <sys/ktls.h>
52 #endif
53 #include <sys/qmath.h>
54 #include <sys/stats.h>
55 #include <sys/sysctl.h>
56 #include <sys/jail.h>
57 #include <sys/malloc.h>
58 #include <sys/refcount.h>
59 #include <sys/mbuf.h>
60 #include <sys/priv.h>
61 #include <sys/proc.h>
62 #include <sys/sdt.h>
63 #include <sys/socket.h>
64 #include <sys/socketvar.h>
65 #include <sys/protosw.h>
66 #include <sys/random.h>
67
68 #include <vm/uma.h>
69
70 #include <net/route.h>
71 #include <net/route/nhop.h>
72 #include <net/if.h>
73 #include <net/if_var.h>
74 #include <net/if_private.h>
75 #include <net/vnet.h>
76
77 #include <netinet/in.h>
78 #include <netinet/in_fib.h>
79 #include <netinet/in_kdtrace.h>
80 #include <netinet/in_pcb.h>
81 #include <netinet/in_systm.h>
82 #include <netinet/in_var.h>
83 #include <netinet/ip.h>
84 #include <netinet/ip_icmp.h>
85 #include <netinet/ip_var.h>
86 #ifdef INET6
87 #include <netinet/icmp6.h>
88 #include <netinet/ip6.h>
89 #include <netinet6/in6_fib.h>
90 #include <netinet6/in6_pcb.h>
91 #include <netinet6/ip6_var.h>
92 #include <netinet6/scope6_var.h>
93 #include <netinet6/nd6.h>
94 #endif
95
96 #include <netinet/tcp.h>
97 #ifdef INVARIANTS
98 #define TCPSTATES
99 #endif
100 #include <netinet/tcp_fsm.h>
101 #include <netinet/tcp_seq.h>
102 #include <netinet/tcp_timer.h>
103 #include <netinet/tcp_var.h>
104 #include <netinet/tcp_ecn.h>
105 #include <netinet/tcp_log_buf.h>
106 #include <netinet/tcp_syncache.h>
107 #include <netinet/tcp_hpts.h>
108 #include <netinet/tcp_lro.h>
109 #include <netinet/cc/cc.h>
110 #include <netinet/tcpip.h>
111 #include <netinet/tcp_fastopen.h>
112 #include <netinet/tcp_accounting.h>
113 #ifdef TCPPCAP
114 #include <netinet/tcp_pcap.h>
115 #endif
116 #ifdef TCP_OFFLOAD
117 #include <netinet/tcp_offload.h>
118 #endif
119 #include <netinet/udp.h>
120 #include <netinet/udp_var.h>
121 #ifdef INET6
122 #include <netinet6/tcp6_var.h>
123 #endif
124
125 #include <netipsec/ipsec_support.h>
126
127 #include <machine/in_cksum.h>
128 #include <crypto/siphash/siphash.h>
129
130 #include <security/mac/mac_framework.h>
131
132 #ifdef INET6
133 static ip6proto_ctlinput_t tcp6_ctlinput;
134 static udp_tun_icmp_t tcp6_ctlinput_viaudp;
135 #endif
136
137 VNET_DEFINE(int, tcp_mssdflt) = TCP_MSS;
138 #ifdef INET6
139 VNET_DEFINE(int, tcp_v6mssdflt) = TCP6_MSS;
140 #endif
141
142 uint32_t tcp_ack_war_time_window = 1000;
143 SYSCTL_UINT(_net_inet_tcp, OID_AUTO, ack_war_timewindow,
144 CTLFLAG_RW,
145 &tcp_ack_war_time_window, 1000,
146 "If the tcp_stack does ack-war prevention how many milliseconds are in its time window?");
147 uint32_t tcp_ack_war_cnt = 5;
148 SYSCTL_UINT(_net_inet_tcp, OID_AUTO, ack_war_cnt,
149 CTLFLAG_RW,
150 &tcp_ack_war_cnt, 5,
151 "If the tcp_stack does ack-war prevention how many acks can be sent in its time window?");
152
153 struct rwlock tcp_function_lock;
154
155 static int
sysctl_net_inet_tcp_mss_check(SYSCTL_HANDLER_ARGS)156 sysctl_net_inet_tcp_mss_check(SYSCTL_HANDLER_ARGS)
157 {
158 int error, new;
159
160 new = V_tcp_mssdflt;
161 error = sysctl_handle_int(oidp, &new, 0, req);
162 if (error == 0 && req->newptr) {
163 if (new < TCP_MINMSS)
164 error = EINVAL;
165 else
166 V_tcp_mssdflt = new;
167 }
168 return (error);
169 }
170
171 SYSCTL_PROC(_net_inet_tcp, TCPCTL_MSSDFLT, mssdflt,
172 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_NEEDGIANT,
173 &VNET_NAME(tcp_mssdflt), 0, &sysctl_net_inet_tcp_mss_check, "I",
174 "Default TCP Maximum Segment Size");
175
176 #ifdef INET6
177 static int
sysctl_net_inet_tcp_mss_v6_check(SYSCTL_HANDLER_ARGS)178 sysctl_net_inet_tcp_mss_v6_check(SYSCTL_HANDLER_ARGS)
179 {
180 int error, new;
181
182 new = V_tcp_v6mssdflt;
183 error = sysctl_handle_int(oidp, &new, 0, req);
184 if (error == 0 && req->newptr) {
185 if (new < TCP_MINMSS)
186 error = EINVAL;
187 else
188 V_tcp_v6mssdflt = new;
189 }
190 return (error);
191 }
192
193 SYSCTL_PROC(_net_inet_tcp, TCPCTL_V6MSSDFLT, v6mssdflt,
194 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_NEEDGIANT,
195 &VNET_NAME(tcp_v6mssdflt), 0, &sysctl_net_inet_tcp_mss_v6_check, "I",
196 "Default TCP Maximum Segment Size for IPv6");
197 #endif /* INET6 */
198
199 /*
200 * Minimum MSS we accept and use. This prevents DoS attacks where
201 * we are forced to a ridiculous low MSS like 20 and send hundreds
202 * of packets instead of one. The effect scales with the available
203 * bandwidth and quickly saturates the CPU and network interface
204 * with packet generation and sending. Set to zero to disable MINMSS
205 * checking. This setting prevents us from sending too small packets.
206 */
207 VNET_DEFINE(int, tcp_minmss) = TCP_MINMSS;
208 SYSCTL_INT(_net_inet_tcp, OID_AUTO, minmss, CTLFLAG_VNET | CTLFLAG_RW,
209 &VNET_NAME(tcp_minmss), 0,
210 "Minimum TCP Maximum Segment Size");
211
212 VNET_DEFINE(int, tcp_do_rfc1323) = 1;
213 SYSCTL_INT(_net_inet_tcp, TCPCTL_DO_RFC1323, rfc1323, CTLFLAG_VNET | CTLFLAG_RW,
214 &VNET_NAME(tcp_do_rfc1323), 0,
215 "Enable rfc1323 (high performance TCP) extensions");
216
217 /*
218 * As of June 2021, several TCP stacks violate RFC 7323 from September 2014.
219 * Some stacks negotiate TS, but never send them after connection setup. Some
220 * stacks negotiate TS, but don't send them when sending keep-alive segments.
221 * These include modern widely deployed TCP stacks.
222 * Therefore tolerating violations for now...
223 */
224 VNET_DEFINE(int, tcp_tolerate_missing_ts) = 1;
225 SYSCTL_INT(_net_inet_tcp, OID_AUTO, tolerate_missing_ts, CTLFLAG_VNET | CTLFLAG_RW,
226 &VNET_NAME(tcp_tolerate_missing_ts), 0,
227 "Tolerate missing TCP timestamps");
228
229 VNET_DEFINE(int, tcp_ts_offset_per_conn) = 1;
230 SYSCTL_INT(_net_inet_tcp, OID_AUTO, ts_offset_per_conn, CTLFLAG_VNET | CTLFLAG_RW,
231 &VNET_NAME(tcp_ts_offset_per_conn), 0,
232 "Initialize TCP timestamps per connection instead of per host pair");
233
234 /* How many connections are pacing */
235 static volatile uint32_t number_of_tcp_connections_pacing = 0;
236 static uint32_t shadow_num_connections = 0;
237 static counter_u64_t tcp_pacing_failures;
238 static counter_u64_t tcp_dgp_failures;
239 static uint32_t shadow_tcp_pacing_dgp = 0;
240 static volatile uint32_t number_of_dgp_connections = 0;
241
242 static int tcp_pacing_limit = 10000;
243 SYSCTL_INT(_net_inet_tcp, OID_AUTO, pacing_limit, CTLFLAG_RW,
244 &tcp_pacing_limit, 1000,
245 "If the TCP stack does pacing, is there a limit (-1 = no, 0 = no pacing N = number of connections)");
246
247 static int tcp_dgp_limit = -1;
248 SYSCTL_INT(_net_inet_tcp, OID_AUTO, dgp_limit, CTLFLAG_RW,
249 &tcp_dgp_limit, -1,
250 "If the TCP stack does DGP, is there a limit (-1 = no, 0 = no dgp N = number of connections)");
251
252 SYSCTL_UINT(_net_inet_tcp, OID_AUTO, pacing_count, CTLFLAG_RD,
253 &shadow_num_connections, 0, "Number of TCP connections being paced");
254
255 SYSCTL_COUNTER_U64(_net_inet_tcp, OID_AUTO, pacing_failures, CTLFLAG_RD,
256 &tcp_pacing_failures, "Number of times we failed to enable pacing to avoid exceeding the limit");
257
258 SYSCTL_COUNTER_U64(_net_inet_tcp, OID_AUTO, dgp_failures, CTLFLAG_RD,
259 &tcp_dgp_failures, "Number of times we failed to enable dgp to avoid exceeding the limit");
260
261 static int tcp_log_debug = 0;
262 SYSCTL_INT(_net_inet_tcp, OID_AUTO, log_debug, CTLFLAG_RW,
263 &tcp_log_debug, 0, "Log errors caused by incoming TCP segments");
264
265 /*
266 * Target size of TCP PCB hash tables. Must be a power of two.
267 *
268 * Note that this can be overridden by the kernel environment
269 * variable net.inet.tcp.tcbhashsize
270 */
271 #ifndef TCBHASHSIZE
272 #define TCBHASHSIZE 0
273 #endif
274 static int tcp_tcbhashsize = TCBHASHSIZE;
275 SYSCTL_INT(_net_inet_tcp, OID_AUTO, tcbhashsize, CTLFLAG_RDTUN,
276 &tcp_tcbhashsize, 0, "Size of TCP control-block hashtable");
277
278 static int do_tcpdrain = 1;
279 SYSCTL_INT(_net_inet_tcp, OID_AUTO, do_tcpdrain, CTLFLAG_RW, &do_tcpdrain, 0,
280 "Enable tcp_drain routine for extra help when low on mbufs");
281
282 SYSCTL_UINT(_net_inet_tcp, OID_AUTO, pcbcount, CTLFLAG_VNET | CTLFLAG_RD,
283 &VNET_NAME(tcbinfo.ipi_count), 0, "Number of active PCBs");
284
285 VNET_DEFINE_STATIC(int, icmp_may_rst) = 1;
286 #define V_icmp_may_rst VNET(icmp_may_rst)
287 SYSCTL_INT(_net_inet_tcp, OID_AUTO, icmp_may_rst, CTLFLAG_VNET | CTLFLAG_RW,
288 &VNET_NAME(icmp_may_rst), 0,
289 "Certain ICMP unreachable messages may abort connections in SYN_SENT");
290
291 VNET_DEFINE_STATIC(int, tcp_isn_reseed_interval) = 0;
292 #define V_tcp_isn_reseed_interval VNET(tcp_isn_reseed_interval)
293 SYSCTL_INT(_net_inet_tcp, OID_AUTO, isn_reseed_interval, CTLFLAG_VNET | CTLFLAG_RW,
294 &VNET_NAME(tcp_isn_reseed_interval), 0,
295 "Seconds between reseeding of ISN secret");
296
297 static int tcp_soreceive_stream;
298 SYSCTL_INT(_net_inet_tcp, OID_AUTO, soreceive_stream, CTLFLAG_RDTUN,
299 &tcp_soreceive_stream, 0, "Using soreceive_stream for TCP sockets");
300
301 VNET_DEFINE(uma_zone_t, sack_hole_zone);
302 #define V_sack_hole_zone VNET(sack_hole_zone)
303 VNET_DEFINE(uint32_t, tcp_map_entries_limit) = 0; /* unlimited */
304 static int
sysctl_net_inet_tcp_map_limit_check(SYSCTL_HANDLER_ARGS)305 sysctl_net_inet_tcp_map_limit_check(SYSCTL_HANDLER_ARGS)
306 {
307 int error;
308 uint32_t new;
309
310 new = V_tcp_map_entries_limit;
311 error = sysctl_handle_int(oidp, &new, 0, req);
312 if (error == 0 && req->newptr) {
313 /* only allow "0" and value > minimum */
314 if (new > 0 && new < TCP_MIN_MAP_ENTRIES_LIMIT)
315 error = EINVAL;
316 else
317 V_tcp_map_entries_limit = new;
318 }
319 return (error);
320 }
321 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, map_limit,
322 CTLFLAG_VNET | CTLTYPE_UINT | CTLFLAG_RW | CTLFLAG_NEEDGIANT,
323 &VNET_NAME(tcp_map_entries_limit), 0,
324 &sysctl_net_inet_tcp_map_limit_check, "IU",
325 "Total sendmap entries limit");
326
327 VNET_DEFINE(uint32_t, tcp_map_split_limit) = 0; /* unlimited */
328 SYSCTL_UINT(_net_inet_tcp, OID_AUTO, split_limit, CTLFLAG_VNET | CTLFLAG_RW,
329 &VNET_NAME(tcp_map_split_limit), 0,
330 "Total sendmap split entries limit");
331
332 #ifdef TCP_HHOOK
333 VNET_DEFINE(struct hhook_head *, tcp_hhh[HHOOK_TCP_LAST+1]);
334 #endif
335
336 #define TS_OFFSET_SECRET_LENGTH SIPHASH_KEY_LENGTH
337 VNET_DEFINE_STATIC(u_char, ts_offset_secret[TS_OFFSET_SECRET_LENGTH]);
338 #define V_ts_offset_secret VNET(ts_offset_secret)
339
340 static int tcp_default_fb_init(struct tcpcb *tp, void **ptr);
341 static void tcp_default_fb_fini(struct tcpcb *tp, int tcb_is_purged);
342 static int tcp_default_handoff_ok(struct tcpcb *tp);
343 static struct inpcb *tcp_notify(struct inpcb *, int);
344 static struct inpcb *tcp_mtudisc_notify(struct inpcb *, int);
345 static struct inpcb *tcp_mtudisc(struct inpcb *, int);
346 static struct inpcb *tcp_drop_syn_sent(struct inpcb *, int);
347 static char * tcp_log_addr(struct in_conninfo *inc, struct tcphdr *th,
348 const void *ip4hdr, const void *ip6hdr);
349 static void tcp_default_switch_failed(struct tcpcb *tp);
350 static ipproto_ctlinput_t tcp_ctlinput;
351 static udp_tun_icmp_t tcp_ctlinput_viaudp;
352
353 static struct tcp_function_block tcp_def_funcblk = {
354 .tfb_tcp_block_name = "freebsd",
355 .tfb_tcp_output = tcp_default_output,
356 .tfb_tcp_do_segment = tcp_do_segment,
357 .tfb_tcp_ctloutput = tcp_default_ctloutput,
358 .tfb_tcp_handoff_ok = tcp_default_handoff_ok,
359 .tfb_tcp_fb_init = tcp_default_fb_init,
360 .tfb_tcp_fb_fini = tcp_default_fb_fini,
361 .tfb_switch_failed = tcp_default_switch_failed,
362 };
363
364 static int tcp_fb_cnt = 0;
365 struct tcp_funchead t_functions;
366 VNET_DEFINE_STATIC(struct tcp_function_block *, tcp_func_set_ptr) = &tcp_def_funcblk;
367 #define V_tcp_func_set_ptr VNET(tcp_func_set_ptr)
368
369 void
tcp_record_dsack(struct tcpcb * tp,tcp_seq start,tcp_seq end,int tlp)370 tcp_record_dsack(struct tcpcb *tp, tcp_seq start, tcp_seq end, int tlp)
371 {
372 TCPSTAT_INC(tcps_dsack_count);
373 tp->t_dsack_pack++;
374 if (tlp == 0) {
375 if (SEQ_GT(end, start)) {
376 tp->t_dsack_bytes += (end - start);
377 TCPSTAT_ADD(tcps_dsack_bytes, (end - start));
378 } else {
379 tp->t_dsack_tlp_bytes += (start - end);
380 TCPSTAT_ADD(tcps_dsack_bytes, (start - end));
381 }
382 } else {
383 if (SEQ_GT(end, start)) {
384 tp->t_dsack_bytes += (end - start);
385 TCPSTAT_ADD(tcps_dsack_tlp_bytes, (end - start));
386 } else {
387 tp->t_dsack_tlp_bytes += (start - end);
388 TCPSTAT_ADD(tcps_dsack_tlp_bytes, (start - end));
389 }
390 }
391 }
392
393 static struct tcp_function_block *
find_tcp_functions_locked(struct tcp_function_set * fs)394 find_tcp_functions_locked(struct tcp_function_set *fs)
395 {
396 struct tcp_function *f;
397 struct tcp_function_block *blk=NULL;
398
399 TAILQ_FOREACH(f, &t_functions, tf_next) {
400 if (strcmp(f->tf_name, fs->function_set_name) == 0) {
401 blk = f->tf_fb;
402 break;
403 }
404 }
405 return(blk);
406 }
407
408 static struct tcp_function_block *
find_tcp_fb_locked(struct tcp_function_block * blk,struct tcp_function ** s)409 find_tcp_fb_locked(struct tcp_function_block *blk, struct tcp_function **s)
410 {
411 struct tcp_function_block *rblk=NULL;
412 struct tcp_function *f;
413
414 TAILQ_FOREACH(f, &t_functions, tf_next) {
415 if (f->tf_fb == blk) {
416 rblk = blk;
417 if (s) {
418 *s = f;
419 }
420 break;
421 }
422 }
423 return (rblk);
424 }
425
426 struct tcp_function_block *
find_and_ref_tcp_functions(struct tcp_function_set * fs)427 find_and_ref_tcp_functions(struct tcp_function_set *fs)
428 {
429 struct tcp_function_block *blk;
430
431 rw_rlock(&tcp_function_lock);
432 blk = find_tcp_functions_locked(fs);
433 if (blk)
434 refcount_acquire(&blk->tfb_refcnt);
435 rw_runlock(&tcp_function_lock);
436 return(blk);
437 }
438
439 struct tcp_function_block *
find_and_ref_tcp_fb(struct tcp_function_block * blk)440 find_and_ref_tcp_fb(struct tcp_function_block *blk)
441 {
442 struct tcp_function_block *rblk;
443
444 rw_rlock(&tcp_function_lock);
445 rblk = find_tcp_fb_locked(blk, NULL);
446 if (rblk)
447 refcount_acquire(&rblk->tfb_refcnt);
448 rw_runlock(&tcp_function_lock);
449 return(rblk);
450 }
451
452 /* Find a matching alias for the given tcp_function_block. */
453 int
find_tcp_function_alias(struct tcp_function_block * blk,struct tcp_function_set * fs)454 find_tcp_function_alias(struct tcp_function_block *blk,
455 struct tcp_function_set *fs)
456 {
457 struct tcp_function *f;
458 int found;
459
460 found = 0;
461 rw_rlock(&tcp_function_lock);
462 TAILQ_FOREACH(f, &t_functions, tf_next) {
463 if ((f->tf_fb == blk) &&
464 (strncmp(f->tf_name, blk->tfb_tcp_block_name,
465 TCP_FUNCTION_NAME_LEN_MAX) != 0)) {
466 /* Matching function block with different name. */
467 strncpy(fs->function_set_name, f->tf_name,
468 TCP_FUNCTION_NAME_LEN_MAX);
469 found = 1;
470 break;
471 }
472 }
473 /* Null terminate the string appropriately. */
474 if (found) {
475 fs->function_set_name[TCP_FUNCTION_NAME_LEN_MAX - 1] = '\0';
476 } else {
477 fs->function_set_name[0] = '\0';
478 }
479 rw_runlock(&tcp_function_lock);
480 return (found);
481 }
482
483 static struct tcp_function_block *
find_and_ref_tcp_default_fb(void)484 find_and_ref_tcp_default_fb(void)
485 {
486 struct tcp_function_block *rblk;
487
488 rw_rlock(&tcp_function_lock);
489 rblk = V_tcp_func_set_ptr;
490 refcount_acquire(&rblk->tfb_refcnt);
491 rw_runlock(&tcp_function_lock);
492 return (rblk);
493 }
494
495 void
tcp_switch_back_to_default(struct tcpcb * tp)496 tcp_switch_back_to_default(struct tcpcb *tp)
497 {
498 struct tcp_function_block *tfb;
499 void *ptr = NULL;
500
501 KASSERT(tp->t_fb != &tcp_def_funcblk,
502 ("%s: called by the built-in default stack", __func__));
503
504 if (tp->t_fb->tfb_tcp_timer_stop_all != NULL)
505 tp->t_fb->tfb_tcp_timer_stop_all(tp);
506
507 /*
508 * Now, we'll find a new function block to use.
509 * Start by trying the current user-selected
510 * default, unless this stack is the user-selected
511 * default.
512 */
513 tfb = find_and_ref_tcp_default_fb();
514 if (tfb == tp->t_fb) {
515 refcount_release(&tfb->tfb_refcnt);
516 tfb = NULL;
517 }
518 /* Does the stack accept this connection? */
519 if (tfb != NULL && (*tfb->tfb_tcp_handoff_ok)(tp)) {
520 refcount_release(&tfb->tfb_refcnt);
521 tfb = NULL;
522 }
523 /* Try to use that stack. */
524 if (tfb != NULL) {
525 /* Initialize the new stack. If it succeeds, we are done. */
526 if (tfb->tfb_tcp_fb_init == NULL ||
527 (*tfb->tfb_tcp_fb_init)(tp, &ptr) == 0) {
528 /* Release the old stack */
529 if (tp->t_fb->tfb_tcp_fb_fini != NULL)
530 (*tp->t_fb->tfb_tcp_fb_fini)(tp, 0);
531 refcount_release(&tp->t_fb->tfb_refcnt);
532 /* Now set in all the pointers */
533 tp->t_fb = tfb;
534 tp->t_fb_ptr = ptr;
535 return;
536 }
537 /*
538 * Initialization failed. Release the reference count on
539 * the looked up default stack.
540 */
541 refcount_release(&tfb->tfb_refcnt);
542 }
543
544 /*
545 * If that wasn't feasible, use the built-in default
546 * stack which is not allowed to reject anyone.
547 */
548 tfb = find_and_ref_tcp_fb(&tcp_def_funcblk);
549 if (tfb == NULL) {
550 /* there always should be a default */
551 panic("Can't refer to tcp_def_funcblk");
552 }
553 if ((*tfb->tfb_tcp_handoff_ok)(tp)) {
554 /* The default stack cannot say no */
555 panic("Default stack rejects a new session?");
556 }
557 if (tfb->tfb_tcp_fb_init != NULL &&
558 (*tfb->tfb_tcp_fb_init)(tp, &ptr)) {
559 /* The default stack cannot fail */
560 panic("Default stack initialization failed");
561 }
562 /* Now release the old stack */
563 if (tp->t_fb->tfb_tcp_fb_fini != NULL)
564 (*tp->t_fb->tfb_tcp_fb_fini)(tp, 0);
565 refcount_release(&tp->t_fb->tfb_refcnt);
566 /* And set in the pointers to the new */
567 tp->t_fb = tfb;
568 tp->t_fb_ptr = ptr;
569 }
570
571 static bool
tcp_recv_udp_tunneled_packet(struct mbuf * m,int off,struct inpcb * inp,const struct sockaddr * sa,void * ctx)572 tcp_recv_udp_tunneled_packet(struct mbuf *m, int off, struct inpcb *inp,
573 const struct sockaddr *sa, void *ctx)
574 {
575 struct ip *iph;
576 #ifdef INET6
577 struct ip6_hdr *ip6;
578 #endif
579 struct udphdr *uh;
580 struct tcphdr *th;
581 int thlen;
582 uint16_t port;
583
584 TCPSTAT_INC(tcps_tunneled_pkts);
585 if ((m->m_flags & M_PKTHDR) == 0) {
586 /* Can't handle one that is not a pkt hdr */
587 TCPSTAT_INC(tcps_tunneled_errs);
588 goto out;
589 }
590 thlen = sizeof(struct tcphdr);
591 if (m->m_len < off + sizeof(struct udphdr) + thlen &&
592 (m = m_pullup(m, off + sizeof(struct udphdr) + thlen)) == NULL) {
593 TCPSTAT_INC(tcps_tunneled_errs);
594 goto out;
595 }
596 iph = mtod(m, struct ip *);
597 uh = (struct udphdr *)((caddr_t)iph + off);
598 th = (struct tcphdr *)(uh + 1);
599 thlen = th->th_off << 2;
600 if (m->m_len < off + sizeof(struct udphdr) + thlen) {
601 m = m_pullup(m, off + sizeof(struct udphdr) + thlen);
602 if (m == NULL) {
603 TCPSTAT_INC(tcps_tunneled_errs);
604 goto out;
605 } else {
606 iph = mtod(m, struct ip *);
607 uh = (struct udphdr *)((caddr_t)iph + off);
608 th = (struct tcphdr *)(uh + 1);
609 }
610 }
611 m->m_pkthdr.tcp_tun_port = port = uh->uh_sport;
612 bcopy(th, uh, m->m_len - off);
613 m->m_len -= sizeof(struct udphdr);
614 m->m_pkthdr.len -= sizeof(struct udphdr);
615 /*
616 * We use the same algorithm for
617 * both UDP and TCP for c-sum. So
618 * the code in tcp_input will skip
619 * the checksum. So we do nothing
620 * with the flag (m->m_pkthdr.csum_flags).
621 */
622 switch (iph->ip_v) {
623 #ifdef INET
624 case IPVERSION:
625 iph->ip_len = htons(ntohs(iph->ip_len) - sizeof(struct udphdr));
626 tcp_input_with_port(&m, &off, IPPROTO_TCP, port);
627 break;
628 #endif
629 #ifdef INET6
630 case IPV6_VERSION >> 4:
631 ip6 = mtod(m, struct ip6_hdr *);
632 ip6->ip6_plen = htons(ntohs(ip6->ip6_plen) - sizeof(struct udphdr));
633 tcp6_input_with_port(&m, &off, IPPROTO_TCP, port);
634 break;
635 #endif
636 default:
637 goto out;
638 break;
639 }
640 return (true);
641 out:
642 m_freem(m);
643
644 return (true);
645 }
646
647 static int
sysctl_net_inet_default_tcp_functions(SYSCTL_HANDLER_ARGS)648 sysctl_net_inet_default_tcp_functions(SYSCTL_HANDLER_ARGS)
649 {
650 int error=ENOENT;
651 struct tcp_function_set fs;
652 struct tcp_function_block *blk;
653
654 memset(&fs, 0, sizeof(fs));
655 rw_rlock(&tcp_function_lock);
656 blk = find_tcp_fb_locked(V_tcp_func_set_ptr, NULL);
657 if (blk) {
658 /* Found him */
659 strcpy(fs.function_set_name, blk->tfb_tcp_block_name);
660 fs.pcbcnt = blk->tfb_refcnt;
661 }
662 rw_runlock(&tcp_function_lock);
663 error = sysctl_handle_string(oidp, fs.function_set_name,
664 sizeof(fs.function_set_name), req);
665
666 /* Check for error or no change */
667 if (error != 0 || req->newptr == NULL)
668 return(error);
669
670 rw_wlock(&tcp_function_lock);
671 blk = find_tcp_functions_locked(&fs);
672 if ((blk == NULL) ||
673 (blk->tfb_flags & TCP_FUNC_BEING_REMOVED)) {
674 error = ENOENT;
675 goto done;
676 }
677 V_tcp_func_set_ptr = blk;
678 done:
679 rw_wunlock(&tcp_function_lock);
680 return (error);
681 }
682
683 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, functions_default,
684 CTLFLAG_VNET | CTLTYPE_STRING | CTLFLAG_RW | CTLFLAG_NEEDGIANT,
685 NULL, 0, sysctl_net_inet_default_tcp_functions, "A",
686 "Set/get the default TCP functions");
687
688 static int
sysctl_net_inet_list_available(SYSCTL_HANDLER_ARGS)689 sysctl_net_inet_list_available(SYSCTL_HANDLER_ARGS)
690 {
691 int error, cnt, linesz;
692 struct tcp_function *f;
693 char *buffer, *cp;
694 size_t bufsz, outsz;
695 bool alias;
696
697 cnt = 0;
698 rw_rlock(&tcp_function_lock);
699 TAILQ_FOREACH(f, &t_functions, tf_next) {
700 cnt++;
701 }
702 rw_runlock(&tcp_function_lock);
703
704 bufsz = (cnt+2) * ((TCP_FUNCTION_NAME_LEN_MAX * 2) + 13) + 1;
705 buffer = malloc(bufsz, M_TEMP, M_WAITOK);
706
707 error = 0;
708 cp = buffer;
709
710 linesz = snprintf(cp, bufsz, "\n%-32s%c %-32s %s\n", "Stack", 'D',
711 "Alias", "PCB count");
712 cp += linesz;
713 bufsz -= linesz;
714 outsz = linesz;
715
716 rw_rlock(&tcp_function_lock);
717 TAILQ_FOREACH(f, &t_functions, tf_next) {
718 alias = (f->tf_name != f->tf_fb->tfb_tcp_block_name);
719 linesz = snprintf(cp, bufsz, "%-32s%c %-32s %u\n",
720 f->tf_fb->tfb_tcp_block_name,
721 (f->tf_fb == V_tcp_func_set_ptr) ? '*' : ' ',
722 alias ? f->tf_name : "-",
723 f->tf_fb->tfb_refcnt);
724 if (linesz >= bufsz) {
725 error = EOVERFLOW;
726 break;
727 }
728 cp += linesz;
729 bufsz -= linesz;
730 outsz += linesz;
731 }
732 rw_runlock(&tcp_function_lock);
733 if (error == 0)
734 error = sysctl_handle_string(oidp, buffer, outsz + 1, req);
735 free(buffer, M_TEMP);
736 return (error);
737 }
738
739 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, functions_available,
740 CTLFLAG_VNET | CTLTYPE_STRING | CTLFLAG_RD | CTLFLAG_NEEDGIANT,
741 NULL, 0, sysctl_net_inet_list_available, "A",
742 "list available TCP Function sets");
743
744 VNET_DEFINE(int, tcp_udp_tunneling_port) = TCP_TUNNELING_PORT_DEFAULT;
745
746 #ifdef INET
747 VNET_DEFINE(struct socket *, udp4_tun_socket) = NULL;
748 #define V_udp4_tun_socket VNET(udp4_tun_socket)
749 #endif
750 #ifdef INET6
751 VNET_DEFINE(struct socket *, udp6_tun_socket) = NULL;
752 #define V_udp6_tun_socket VNET(udp6_tun_socket)
753 #endif
754
755 static struct sx tcpoudp_lock;
756
757 static void
tcp_over_udp_stop(void)758 tcp_over_udp_stop(void)
759 {
760
761 sx_assert(&tcpoudp_lock, SA_XLOCKED);
762
763 #ifdef INET
764 if (V_udp4_tun_socket != NULL) {
765 soclose(V_udp4_tun_socket);
766 V_udp4_tun_socket = NULL;
767 }
768 #endif
769 #ifdef INET6
770 if (V_udp6_tun_socket != NULL) {
771 soclose(V_udp6_tun_socket);
772 V_udp6_tun_socket = NULL;
773 }
774 #endif
775 }
776
777 static int
tcp_over_udp_start(void)778 tcp_over_udp_start(void)
779 {
780 uint16_t port;
781 int ret;
782 #ifdef INET
783 struct sockaddr_in sin;
784 #endif
785 #ifdef INET6
786 struct sockaddr_in6 sin6;
787 #endif
788
789 sx_assert(&tcpoudp_lock, SA_XLOCKED);
790
791 port = V_tcp_udp_tunneling_port;
792 if (ntohs(port) == 0) {
793 /* Must have a port set */
794 return (EINVAL);
795 }
796 #ifdef INET
797 if (V_udp4_tun_socket != NULL) {
798 /* Already running -- must stop first */
799 return (EALREADY);
800 }
801 #endif
802 #ifdef INET6
803 if (V_udp6_tun_socket != NULL) {
804 /* Already running -- must stop first */
805 return (EALREADY);
806 }
807 #endif
808 #ifdef INET
809 if ((ret = socreate(PF_INET, &V_udp4_tun_socket,
810 SOCK_DGRAM, IPPROTO_UDP,
811 curthread->td_ucred, curthread))) {
812 tcp_over_udp_stop();
813 return (ret);
814 }
815 /* Call the special UDP hook. */
816 if ((ret = udp_set_kernel_tunneling(V_udp4_tun_socket,
817 tcp_recv_udp_tunneled_packet,
818 tcp_ctlinput_viaudp,
819 NULL))) {
820 tcp_over_udp_stop();
821 return (ret);
822 }
823 /* Ok, we have a socket, bind it to the port. */
824 memset(&sin, 0, sizeof(struct sockaddr_in));
825 sin.sin_len = sizeof(struct sockaddr_in);
826 sin.sin_family = AF_INET;
827 sin.sin_port = htons(port);
828 if ((ret = sobind(V_udp4_tun_socket,
829 (struct sockaddr *)&sin, curthread))) {
830 tcp_over_udp_stop();
831 return (ret);
832 }
833 #endif
834 #ifdef INET6
835 if ((ret = socreate(PF_INET6, &V_udp6_tun_socket,
836 SOCK_DGRAM, IPPROTO_UDP,
837 curthread->td_ucred, curthread))) {
838 tcp_over_udp_stop();
839 return (ret);
840 }
841 /* Call the special UDP hook. */
842 if ((ret = udp_set_kernel_tunneling(V_udp6_tun_socket,
843 tcp_recv_udp_tunneled_packet,
844 tcp6_ctlinput_viaudp,
845 NULL))) {
846 tcp_over_udp_stop();
847 return (ret);
848 }
849 /* Ok, we have a socket, bind it to the port. */
850 memset(&sin6, 0, sizeof(struct sockaddr_in6));
851 sin6.sin6_len = sizeof(struct sockaddr_in6);
852 sin6.sin6_family = AF_INET6;
853 sin6.sin6_port = htons(port);
854 if ((ret = sobind(V_udp6_tun_socket,
855 (struct sockaddr *)&sin6, curthread))) {
856 tcp_over_udp_stop();
857 return (ret);
858 }
859 #endif
860 return (0);
861 }
862
863 static int
sysctl_net_inet_tcp_udp_tunneling_port_check(SYSCTL_HANDLER_ARGS)864 sysctl_net_inet_tcp_udp_tunneling_port_check(SYSCTL_HANDLER_ARGS)
865 {
866 int error;
867 uint32_t old, new;
868
869 old = V_tcp_udp_tunneling_port;
870 new = old;
871 error = sysctl_handle_int(oidp, &new, 0, req);
872 if ((error == 0) &&
873 (req->newptr != NULL)) {
874 if ((new < TCP_TUNNELING_PORT_MIN) ||
875 (new > TCP_TUNNELING_PORT_MAX)) {
876 error = EINVAL;
877 } else {
878 sx_xlock(&tcpoudp_lock);
879 V_tcp_udp_tunneling_port = new;
880 if (old != 0) {
881 tcp_over_udp_stop();
882 }
883 if (new != 0) {
884 error = tcp_over_udp_start();
885 if (error != 0) {
886 V_tcp_udp_tunneling_port = 0;
887 }
888 }
889 sx_xunlock(&tcpoudp_lock);
890 }
891 }
892 return (error);
893 }
894
895 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, udp_tunneling_port,
896 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE,
897 &VNET_NAME(tcp_udp_tunneling_port),
898 0, &sysctl_net_inet_tcp_udp_tunneling_port_check, "IU",
899 "Tunneling port for tcp over udp");
900
901 VNET_DEFINE(int, tcp_udp_tunneling_overhead) = TCP_TUNNELING_OVERHEAD_DEFAULT;
902
903 static int
sysctl_net_inet_tcp_udp_tunneling_overhead_check(SYSCTL_HANDLER_ARGS)904 sysctl_net_inet_tcp_udp_tunneling_overhead_check(SYSCTL_HANDLER_ARGS)
905 {
906 int error, new;
907
908 new = V_tcp_udp_tunneling_overhead;
909 error = sysctl_handle_int(oidp, &new, 0, req);
910 if (error == 0 && req->newptr) {
911 if ((new < TCP_TUNNELING_OVERHEAD_MIN) ||
912 (new > TCP_TUNNELING_OVERHEAD_MAX))
913 error = EINVAL;
914 else
915 V_tcp_udp_tunneling_overhead = new;
916 }
917 return (error);
918 }
919
920 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, udp_tunneling_overhead,
921 CTLFLAG_VNET | CTLTYPE_INT | CTLFLAG_RW | CTLFLAG_MPSAFE,
922 &VNET_NAME(tcp_udp_tunneling_overhead),
923 0, &sysctl_net_inet_tcp_udp_tunneling_overhead_check, "IU",
924 "MSS reduction when using tcp over udp");
925
926 /*
927 * Exports one (struct tcp_function_info) for each alias/name.
928 */
929 static int
sysctl_net_inet_list_func_info(SYSCTL_HANDLER_ARGS)930 sysctl_net_inet_list_func_info(SYSCTL_HANDLER_ARGS)
931 {
932 int cnt, error;
933 struct tcp_function *f;
934 struct tcp_function_info tfi;
935
936 /*
937 * We don't allow writes.
938 */
939 if (req->newptr != NULL)
940 return (EINVAL);
941
942 /*
943 * Wire the old buffer so we can directly copy the functions to
944 * user space without dropping the lock.
945 */
946 if (req->oldptr != NULL) {
947 error = sysctl_wire_old_buffer(req, 0);
948 if (error)
949 return (error);
950 }
951
952 /*
953 * Walk the list and copy out matching entries. If INVARIANTS
954 * is compiled in, also walk the list to verify the length of
955 * the list matches what we have recorded.
956 */
957 rw_rlock(&tcp_function_lock);
958
959 cnt = 0;
960 #ifndef INVARIANTS
961 if (req->oldptr == NULL) {
962 cnt = tcp_fb_cnt;
963 goto skip_loop;
964 }
965 #endif
966 TAILQ_FOREACH(f, &t_functions, tf_next) {
967 #ifdef INVARIANTS
968 cnt++;
969 #endif
970 if (req->oldptr != NULL) {
971 bzero(&tfi, sizeof(tfi));
972 tfi.tfi_refcnt = f->tf_fb->tfb_refcnt;
973 tfi.tfi_id = f->tf_fb->tfb_id;
974 (void)strlcpy(tfi.tfi_alias, f->tf_name,
975 sizeof(tfi.tfi_alias));
976 (void)strlcpy(tfi.tfi_name,
977 f->tf_fb->tfb_tcp_block_name, sizeof(tfi.tfi_name));
978 error = SYSCTL_OUT(req, &tfi, sizeof(tfi));
979 /*
980 * Don't stop on error, as that is the
981 * mechanism we use to accumulate length
982 * information if the buffer was too short.
983 */
984 }
985 }
986 KASSERT(cnt == tcp_fb_cnt,
987 ("%s: cnt (%d) != tcp_fb_cnt (%d)", __func__, cnt, tcp_fb_cnt));
988 #ifndef INVARIANTS
989 skip_loop:
990 #endif
991 rw_runlock(&tcp_function_lock);
992 if (req->oldptr == NULL)
993 error = SYSCTL_OUT(req, NULL,
994 (cnt + 1) * sizeof(struct tcp_function_info));
995
996 return (error);
997 }
998
999 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, function_info,
1000 CTLTYPE_OPAQUE | CTLFLAG_SKIP | CTLFLAG_RD | CTLFLAG_MPSAFE,
1001 NULL, 0, sysctl_net_inet_list_func_info, "S,tcp_function_info",
1002 "List TCP function block name-to-ID mappings");
1003
1004 /*
1005 * tfb_tcp_handoff_ok() function for the default stack.
1006 * Note that we'll basically try to take all comers.
1007 */
1008 static int
tcp_default_handoff_ok(struct tcpcb * tp)1009 tcp_default_handoff_ok(struct tcpcb *tp)
1010 {
1011
1012 return (0);
1013 }
1014
1015 /*
1016 * tfb_tcp_fb_init() function for the default stack.
1017 *
1018 * This handles making sure we have appropriate timers set if you are
1019 * transitioning a socket that has some amount of setup done.
1020 *
1021 * The init() fuction from the default can *never* return non-zero i.e.
1022 * it is required to always succeed since it is the stack of last resort!
1023 */
1024 static int
tcp_default_fb_init(struct tcpcb * tp,void ** ptr)1025 tcp_default_fb_init(struct tcpcb *tp, void **ptr)
1026 {
1027 struct socket *so = tptosocket(tp);
1028 int rexmt;
1029
1030 INP_WLOCK_ASSERT(tptoinpcb(tp));
1031 /* We don't use the pointer */
1032 *ptr = NULL;
1033
1034 KASSERT(tp->t_state < TCPS_TIME_WAIT,
1035 ("%s: connection %p in unexpected state %d", __func__, tp,
1036 tp->t_state));
1037
1038 /* Make sure we get no interesting mbuf queuing behavior */
1039 /* All mbuf queue/ack compress flags should be off */
1040 tcp_lro_features_off(tp);
1041
1042 /* Cancel the GP measurement in progress */
1043 tp->t_flags &= ~TF_GPUTINPROG;
1044 /* Validate the timers are not in usec, if they are convert */
1045 tcp_change_time_units(tp, TCP_TMR_GRANULARITY_TICKS);
1046 if ((tp->t_state == TCPS_SYN_SENT) ||
1047 (tp->t_state == TCPS_SYN_RECEIVED))
1048 rexmt = tcp_rexmit_initial * tcp_backoff[tp->t_rxtshift];
1049 else
1050 rexmt = TCP_REXMTVAL(tp) * tcp_backoff[tp->t_rxtshift];
1051 if (tp->t_rxtshift == 0)
1052 tp->t_rxtcur = rexmt;
1053 else
1054 TCPT_RANGESET(tp->t_rxtcur, rexmt, tp->t_rttmin, TCPTV_REXMTMAX);
1055
1056 /*
1057 * Nothing to do for ESTABLISHED or LISTEN states. And, we don't
1058 * know what to do for unexpected states (which includes TIME_WAIT).
1059 */
1060 if (tp->t_state <= TCPS_LISTEN || tp->t_state >= TCPS_TIME_WAIT)
1061 return (0);
1062
1063 /*
1064 * Make sure some kind of transmission timer is set if there is
1065 * outstanding data.
1066 */
1067 if ((!TCPS_HAVEESTABLISHED(tp->t_state) || sbavail(&so->so_snd) ||
1068 tp->snd_una != tp->snd_max) && !(tcp_timer_active(tp, TT_REXMT) ||
1069 tcp_timer_active(tp, TT_PERSIST))) {
1070 /*
1071 * If the session has established and it looks like it should
1072 * be in the persist state, set the persist timer. Otherwise,
1073 * set the retransmit timer.
1074 */
1075 if (TCPS_HAVEESTABLISHED(tp->t_state) && tp->snd_wnd == 0 &&
1076 (int32_t)(tp->snd_nxt - tp->snd_una) <
1077 (int32_t)sbavail(&so->so_snd))
1078 tcp_setpersist(tp);
1079 else
1080 tcp_timer_activate(tp, TT_REXMT, TP_RXTCUR(tp));
1081 }
1082
1083 /* All non-embryonic sessions get a keepalive timer. */
1084 if (!tcp_timer_active(tp, TT_KEEP))
1085 tcp_timer_activate(tp, TT_KEEP,
1086 TCPS_HAVEESTABLISHED(tp->t_state) ? TP_KEEPIDLE(tp) :
1087 TP_KEEPINIT(tp));
1088
1089 /*
1090 * Make sure critical variables are initialized
1091 * if transitioning while in Recovery.
1092 */
1093 if IN_FASTRECOVERY(tp->t_flags) {
1094 if (tp->sackhint.recover_fs == 0)
1095 tp->sackhint.recover_fs = max(1,
1096 tp->snd_nxt - tp->snd_una);
1097 }
1098
1099 return (0);
1100 }
1101
1102 /*
1103 * tfb_tcp_fb_fini() function for the default stack.
1104 *
1105 * This changes state as necessary (or prudent) to prepare for another stack
1106 * to assume responsibility for the connection.
1107 */
1108 static void
tcp_default_fb_fini(struct tcpcb * tp,int tcb_is_purged)1109 tcp_default_fb_fini(struct tcpcb *tp, int tcb_is_purged)
1110 {
1111
1112 INP_WLOCK_ASSERT(tptoinpcb(tp));
1113
1114 #ifdef TCP_BLACKBOX
1115 tcp_log_flowend(tp);
1116 #endif
1117 tp->t_acktime = 0;
1118 return;
1119 }
1120
1121 MALLOC_DEFINE(M_TCPLOG, "tcplog", "TCP address and flags print buffers");
1122 MALLOC_DEFINE(M_TCPFUNCTIONS, "tcpfunc", "TCP function set memory");
1123
1124 static struct mtx isn_mtx;
1125
1126 #define ISN_LOCK_INIT() mtx_init(&isn_mtx, "isn_mtx", NULL, MTX_DEF)
1127 #define ISN_LOCK() mtx_lock(&isn_mtx)
1128 #define ISN_UNLOCK() mtx_unlock(&isn_mtx)
1129
1130 INPCBSTORAGE_DEFINE(tcpcbstor, tcpcb, "tcpinp", "tcp_inpcb", "tcp", "tcphash");
1131
1132 /*
1133 * Take a value and get the next power of 2 that doesn't overflow.
1134 * Used to size the tcp_inpcb hash buckets.
1135 */
1136 static int
maketcp_hashsize(int size)1137 maketcp_hashsize(int size)
1138 {
1139 int hashsize;
1140
1141 /*
1142 * auto tune.
1143 * get the next power of 2 higher than maxsockets.
1144 */
1145 hashsize = 1 << fls(size);
1146 /* catch overflow, and just go one power of 2 smaller */
1147 if (hashsize < size) {
1148 hashsize = 1 << (fls(size) - 1);
1149 }
1150 return (hashsize);
1151 }
1152
1153 static volatile int next_tcp_stack_id = 1;
1154
1155 /*
1156 * Register a TCP function block with the name provided in the names
1157 * array. (Note that this function does NOT automatically register
1158 * blk->tfb_tcp_block_name as a stack name. Therefore, you should
1159 * explicitly include blk->tfb_tcp_block_name in the list of names if
1160 * you wish to register the stack with that name.)
1161 *
1162 * Either all name registrations will succeed or all will fail. If
1163 * a name registration fails, the function will update the num_names
1164 * argument to point to the array index of the name that encountered
1165 * the failure.
1166 *
1167 * Returns 0 on success, or an error code on failure.
1168 */
1169 int
register_tcp_functions_as_names(struct tcp_function_block * blk,int wait,const char * names[],int * num_names)1170 register_tcp_functions_as_names(struct tcp_function_block *blk, int wait,
1171 const char *names[], int *num_names)
1172 {
1173 struct tcp_function *n;
1174 struct tcp_function_set fs;
1175 int error, i;
1176
1177 KASSERT(names != NULL && *num_names > 0,
1178 ("%s: Called with 0-length name list", __func__));
1179 KASSERT(names != NULL, ("%s: Called with NULL name list", __func__));
1180 KASSERT(rw_initialized(&tcp_function_lock),
1181 ("%s: called too early", __func__));
1182
1183 if ((blk->tfb_tcp_output == NULL) ||
1184 (blk->tfb_tcp_do_segment == NULL) ||
1185 (blk->tfb_tcp_ctloutput == NULL) ||
1186 (blk->tfb_tcp_handoff_ok == NULL) ||
1187 (strlen(blk->tfb_tcp_block_name) == 0)) {
1188 /*
1189 * These functions are required and you
1190 * need a name.
1191 */
1192 *num_names = 0;
1193 return (EINVAL);
1194 }
1195
1196 if (blk->tfb_flags & TCP_FUNC_BEING_REMOVED) {
1197 *num_names = 0;
1198 return (EINVAL);
1199 }
1200
1201 refcount_init(&blk->tfb_refcnt, 0);
1202 blk->tfb_id = atomic_fetchadd_int(&next_tcp_stack_id, 1);
1203 for (i = 0; i < *num_names; i++) {
1204 n = malloc(sizeof(struct tcp_function), M_TCPFUNCTIONS, wait);
1205 if (n == NULL) {
1206 error = ENOMEM;
1207 goto cleanup;
1208 }
1209 n->tf_fb = blk;
1210
1211 (void)strlcpy(fs.function_set_name, names[i],
1212 sizeof(fs.function_set_name));
1213 rw_wlock(&tcp_function_lock);
1214 if (find_tcp_functions_locked(&fs) != NULL) {
1215 /* Duplicate name space not allowed */
1216 rw_wunlock(&tcp_function_lock);
1217 free(n, M_TCPFUNCTIONS);
1218 error = EALREADY;
1219 goto cleanup;
1220 }
1221 (void)strlcpy(n->tf_name, names[i], sizeof(n->tf_name));
1222 TAILQ_INSERT_TAIL(&t_functions, n, tf_next);
1223 tcp_fb_cnt++;
1224 rw_wunlock(&tcp_function_lock);
1225 }
1226 return(0);
1227
1228 cleanup:
1229 /*
1230 * Deregister the names we just added. Because registration failed
1231 * for names[i], we don't need to deregister that name.
1232 */
1233 *num_names = i;
1234 rw_wlock(&tcp_function_lock);
1235 while (--i >= 0) {
1236 TAILQ_FOREACH(n, &t_functions, tf_next) {
1237 if (!strncmp(n->tf_name, names[i],
1238 TCP_FUNCTION_NAME_LEN_MAX)) {
1239 TAILQ_REMOVE(&t_functions, n, tf_next);
1240 tcp_fb_cnt--;
1241 n->tf_fb = NULL;
1242 free(n, M_TCPFUNCTIONS);
1243 break;
1244 }
1245 }
1246 }
1247 rw_wunlock(&tcp_function_lock);
1248 return (error);
1249 }
1250
1251 /*
1252 * Register a TCP function block using the name provided in the name
1253 * argument.
1254 *
1255 * Returns 0 on success, or an error code on failure.
1256 */
1257 int
register_tcp_functions_as_name(struct tcp_function_block * blk,const char * name,int wait)1258 register_tcp_functions_as_name(struct tcp_function_block *blk, const char *name,
1259 int wait)
1260 {
1261 const char *name_list[1];
1262 int num_names, rv;
1263
1264 num_names = 1;
1265 if (name != NULL)
1266 name_list[0] = name;
1267 else
1268 name_list[0] = blk->tfb_tcp_block_name;
1269 rv = register_tcp_functions_as_names(blk, wait, name_list, &num_names);
1270 return (rv);
1271 }
1272
1273 /*
1274 * Register a TCP function block using the name defined in
1275 * blk->tfb_tcp_block_name.
1276 *
1277 * Returns 0 on success, or an error code on failure.
1278 */
1279 int
register_tcp_functions(struct tcp_function_block * blk,int wait)1280 register_tcp_functions(struct tcp_function_block *blk, int wait)
1281 {
1282
1283 return (register_tcp_functions_as_name(blk, NULL, wait));
1284 }
1285
1286 /*
1287 * Deregister all names associated with a function block. This
1288 * functionally removes the function block from use within the system.
1289 *
1290 * When called with a true quiesce argument, mark the function block
1291 * as being removed so no more stacks will use it and determine
1292 * whether the removal would succeed.
1293 *
1294 * When called with a false quiesce argument, actually attempt the
1295 * removal.
1296 *
1297 * When called with a force argument, attempt to switch all TCBs to
1298 * use the default stack instead of returning EBUSY.
1299 *
1300 * Returns 0 on success (or if the removal would succeed), or an error
1301 * code on failure.
1302 */
1303 int
deregister_tcp_functions(struct tcp_function_block * blk,bool quiesce,bool force)1304 deregister_tcp_functions(struct tcp_function_block *blk, bool quiesce,
1305 bool force)
1306 {
1307 struct tcp_function *f;
1308 VNET_ITERATOR_DECL(vnet_iter);
1309
1310 if (blk == &tcp_def_funcblk) {
1311 /* You can't un-register the default */
1312 return (EPERM);
1313 }
1314 rw_wlock(&tcp_function_lock);
1315 VNET_LIST_RLOCK_NOSLEEP();
1316 VNET_FOREACH(vnet_iter) {
1317 CURVNET_SET(vnet_iter);
1318 if (blk == V_tcp_func_set_ptr) {
1319 /* You can't free the current default in some vnet. */
1320 CURVNET_RESTORE();
1321 VNET_LIST_RUNLOCK_NOSLEEP();
1322 rw_wunlock(&tcp_function_lock);
1323 return (EBUSY);
1324 }
1325 CURVNET_RESTORE();
1326 }
1327 VNET_LIST_RUNLOCK_NOSLEEP();
1328 /* Mark the block so no more stacks can use it. */
1329 blk->tfb_flags |= TCP_FUNC_BEING_REMOVED;
1330 /*
1331 * If TCBs are still attached to the stack, attempt to switch them
1332 * to the default stack.
1333 */
1334 if (force && blk->tfb_refcnt) {
1335 struct inpcb *inp;
1336 struct tcpcb *tp;
1337 VNET_ITERATOR_DECL(vnet_iter);
1338
1339 rw_wunlock(&tcp_function_lock);
1340
1341 VNET_LIST_RLOCK();
1342 VNET_FOREACH(vnet_iter) {
1343 CURVNET_SET(vnet_iter);
1344 struct inpcb_iterator inpi = INP_ALL_ITERATOR(&V_tcbinfo,
1345 INPLOOKUP_WLOCKPCB);
1346
1347 while ((inp = inp_next(&inpi)) != NULL) {
1348 tp = intotcpcb(inp);
1349 if (tp == NULL || tp->t_fb != blk)
1350 continue;
1351 tcp_switch_back_to_default(tp);
1352 }
1353 CURVNET_RESTORE();
1354 }
1355 VNET_LIST_RUNLOCK();
1356
1357 rw_wlock(&tcp_function_lock);
1358 }
1359 if (blk->tfb_refcnt) {
1360 /* TCBs still attached. */
1361 rw_wunlock(&tcp_function_lock);
1362 return (EBUSY);
1363 }
1364 if (quiesce) {
1365 /* Skip removal. */
1366 rw_wunlock(&tcp_function_lock);
1367 return (0);
1368 }
1369 /* Remove any function names that map to this function block. */
1370 while (find_tcp_fb_locked(blk, &f) != NULL) {
1371 TAILQ_REMOVE(&t_functions, f, tf_next);
1372 tcp_fb_cnt--;
1373 f->tf_fb = NULL;
1374 free(f, M_TCPFUNCTIONS);
1375 }
1376 rw_wunlock(&tcp_function_lock);
1377 return (0);
1378 }
1379
1380 static void
tcp_drain(void)1381 tcp_drain(void)
1382 {
1383 struct epoch_tracker et;
1384 VNET_ITERATOR_DECL(vnet_iter);
1385
1386 if (!do_tcpdrain)
1387 return;
1388
1389 NET_EPOCH_ENTER(et);
1390 VNET_LIST_RLOCK_NOSLEEP();
1391 VNET_FOREACH(vnet_iter) {
1392 CURVNET_SET(vnet_iter);
1393 struct inpcb_iterator inpi = INP_ALL_ITERATOR(&V_tcbinfo,
1394 INPLOOKUP_WLOCKPCB);
1395 struct inpcb *inpb;
1396 struct tcpcb *tcpb;
1397
1398 /*
1399 * Walk the tcpbs, if existing, and flush the reassembly queue,
1400 * if there is one...
1401 * XXX: The "Net/3" implementation doesn't imply that the TCP
1402 * reassembly queue should be flushed, but in a situation
1403 * where we're really low on mbufs, this is potentially
1404 * useful.
1405 */
1406 while ((inpb = inp_next(&inpi)) != NULL) {
1407 if ((tcpb = intotcpcb(inpb)) != NULL) {
1408 tcp_reass_flush(tcpb);
1409 tcp_clean_sackreport(tcpb);
1410 #ifdef TCP_BLACKBOX
1411 tcp_log_drain(tcpb);
1412 #endif
1413 #ifdef TCPPCAP
1414 if (tcp_pcap_aggressive_free) {
1415 /* Free the TCP PCAP queues. */
1416 tcp_pcap_drain(&(tcpb->t_inpkts));
1417 tcp_pcap_drain(&(tcpb->t_outpkts));
1418 }
1419 #endif
1420 }
1421 }
1422 CURVNET_RESTORE();
1423 }
1424 VNET_LIST_RUNLOCK_NOSLEEP();
1425 NET_EPOCH_EXIT(et);
1426 }
1427
1428 static void
tcp_vnet_init(void * arg __unused)1429 tcp_vnet_init(void *arg __unused)
1430 {
1431
1432 #ifdef TCP_HHOOK
1433 if (hhook_head_register(HHOOK_TYPE_TCP, HHOOK_TCP_EST_IN,
1434 &V_tcp_hhh[HHOOK_TCP_EST_IN], HHOOK_NOWAIT|HHOOK_HEADISINVNET) != 0)
1435 printf("%s: WARNING: unable to register helper hook\n", __func__);
1436 if (hhook_head_register(HHOOK_TYPE_TCP, HHOOK_TCP_EST_OUT,
1437 &V_tcp_hhh[HHOOK_TCP_EST_OUT], HHOOK_NOWAIT|HHOOK_HEADISINVNET) != 0)
1438 printf("%s: WARNING: unable to register helper hook\n", __func__);
1439 #endif
1440 #ifdef STATS
1441 if (tcp_stats_init())
1442 printf("%s: WARNING: unable to initialise TCP stats\n",
1443 __func__);
1444 #endif
1445 in_pcbinfo_init(&V_tcbinfo, &tcpcbstor, tcp_tcbhashsize,
1446 tcp_tcbhashsize);
1447
1448 syncache_init();
1449 tcp_hc_init();
1450
1451 TUNABLE_INT_FETCH("net.inet.tcp.sack.enable", &V_tcp_do_sack);
1452 V_sack_hole_zone = uma_zcreate("sackhole", sizeof(struct sackhole),
1453 NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, 0);
1454
1455 tcp_fastopen_init();
1456
1457 COUNTER_ARRAY_ALLOC(V_tcps_states, TCP_NSTATES, M_WAITOK);
1458 VNET_PCPUSTAT_ALLOC(tcpstat, M_WAITOK);
1459
1460 V_tcp_msl = TCPTV_MSL;
1461 }
1462 VNET_SYSINIT(tcp_vnet_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH,
1463 tcp_vnet_init, NULL);
1464
1465 static void
tcp_init(void * arg __unused)1466 tcp_init(void *arg __unused)
1467 {
1468 int hashsize;
1469
1470 tcp_reass_global_init();
1471
1472 /* XXX virtualize those below? */
1473 tcp_delacktime = TCPTV_DELACK;
1474 tcp_keepinit = TCPTV_KEEP_INIT;
1475 tcp_keepidle = TCPTV_KEEP_IDLE;
1476 tcp_keepintvl = TCPTV_KEEPINTVL;
1477 tcp_maxpersistidle = TCPTV_KEEP_IDLE;
1478 tcp_rexmit_initial = TCPTV_RTOBASE;
1479 if (tcp_rexmit_initial < 1)
1480 tcp_rexmit_initial = 1;
1481 tcp_rexmit_min = TCPTV_MIN;
1482 if (tcp_rexmit_min < 1)
1483 tcp_rexmit_min = 1;
1484 tcp_persmin = TCPTV_PERSMIN;
1485 tcp_persmax = TCPTV_PERSMAX;
1486 tcp_rexmit_slop = TCPTV_CPU_VAR;
1487 tcp_finwait2_timeout = TCPTV_FINWAIT2_TIMEOUT;
1488
1489 /* Setup the tcp function block list */
1490 TAILQ_INIT(&t_functions);
1491 rw_init(&tcp_function_lock, "tcp_func_lock");
1492 register_tcp_functions(&tcp_def_funcblk, M_WAITOK);
1493 sx_init(&tcpoudp_lock, "TCP over UDP configuration");
1494 #ifdef TCP_BLACKBOX
1495 /* Initialize the TCP logging data. */
1496 tcp_log_init();
1497 #endif
1498 arc4rand(&V_ts_offset_secret, sizeof(V_ts_offset_secret), 0);
1499
1500 if (tcp_soreceive_stream) {
1501 #ifdef INET
1502 tcp_protosw.pr_soreceive = soreceive_stream;
1503 #endif
1504 #ifdef INET6
1505 tcp6_protosw.pr_soreceive = soreceive_stream;
1506 #endif /* INET6 */
1507 }
1508
1509 #ifdef INET6
1510 max_protohdr_grow(sizeof(struct ip6_hdr) + sizeof(struct tcphdr));
1511 #else /* INET6 */
1512 max_protohdr_grow(sizeof(struct tcpiphdr));
1513 #endif /* INET6 */
1514
1515 ISN_LOCK_INIT();
1516 EVENTHANDLER_REGISTER(shutdown_pre_sync, tcp_fini, NULL,
1517 SHUTDOWN_PRI_DEFAULT);
1518 EVENTHANDLER_REGISTER(vm_lowmem, tcp_drain, NULL, LOWMEM_PRI_DEFAULT);
1519 EVENTHANDLER_REGISTER(mbuf_lowmem, tcp_drain, NULL, LOWMEM_PRI_DEFAULT);
1520
1521 tcp_inp_lro_direct_queue = counter_u64_alloc(M_WAITOK);
1522 tcp_inp_lro_wokeup_queue = counter_u64_alloc(M_WAITOK);
1523 tcp_inp_lro_compressed = counter_u64_alloc(M_WAITOK);
1524 tcp_inp_lro_locks_taken = counter_u64_alloc(M_WAITOK);
1525 tcp_extra_mbuf = counter_u64_alloc(M_WAITOK);
1526 tcp_would_have_but = counter_u64_alloc(M_WAITOK);
1527 tcp_comp_total = counter_u64_alloc(M_WAITOK);
1528 tcp_uncomp_total = counter_u64_alloc(M_WAITOK);
1529 tcp_bad_csums = counter_u64_alloc(M_WAITOK);
1530 tcp_pacing_failures = counter_u64_alloc(M_WAITOK);
1531 tcp_dgp_failures = counter_u64_alloc(M_WAITOK);
1532 #ifdef TCPPCAP
1533 tcp_pcap_init();
1534 #endif
1535
1536 hashsize = tcp_tcbhashsize;
1537 if (hashsize == 0) {
1538 /*
1539 * Auto tune the hash size based on maxsockets.
1540 * A perfect hash would have a 1:1 mapping
1541 * (hashsize = maxsockets) however it's been
1542 * suggested that O(2) average is better.
1543 */
1544 hashsize = maketcp_hashsize(maxsockets / 4);
1545 /*
1546 * Our historical default is 512,
1547 * do not autotune lower than this.
1548 */
1549 if (hashsize < 512)
1550 hashsize = 512;
1551 if (bootverbose)
1552 printf("%s: %s auto tuned to %d\n", __func__,
1553 "net.inet.tcp.tcbhashsize", hashsize);
1554 }
1555 /*
1556 * We require a hashsize to be a power of two.
1557 * Previously if it was not a power of two we would just reset it
1558 * back to 512, which could be a nasty surprise if you did not notice
1559 * the error message.
1560 * Instead what we do is clip it to the closest power of two lower
1561 * than the specified hash value.
1562 */
1563 if (!powerof2(hashsize)) {
1564 int oldhashsize = hashsize;
1565
1566 hashsize = maketcp_hashsize(hashsize);
1567 /* prevent absurdly low value */
1568 if (hashsize < 16)
1569 hashsize = 16;
1570 printf("%s: WARNING: TCB hash size not a power of 2, "
1571 "clipped from %d to %d.\n", __func__, oldhashsize,
1572 hashsize);
1573 }
1574 tcp_tcbhashsize = hashsize;
1575
1576 #ifdef INET
1577 IPPROTO_REGISTER(IPPROTO_TCP, tcp_input, tcp_ctlinput);
1578 #endif
1579 #ifdef INET6
1580 IP6PROTO_REGISTER(IPPROTO_TCP, tcp6_input, tcp6_ctlinput);
1581 #endif
1582 }
1583 SYSINIT(tcp_init, SI_SUB_PROTO_DOMAIN, SI_ORDER_THIRD, tcp_init, NULL);
1584
1585 #ifdef VIMAGE
1586 static void
tcp_destroy(void * unused __unused)1587 tcp_destroy(void *unused __unused)
1588 {
1589 int n;
1590 #ifdef TCP_HHOOK
1591 int error;
1592 #endif
1593
1594 /*
1595 * All our processes are gone, all our sockets should be cleaned
1596 * up, which means, we should be past the tcp_discardcb() calls.
1597 * Sleep to let all tcpcb timers really disappear and cleanup.
1598 */
1599 for (;;) {
1600 INP_INFO_WLOCK(&V_tcbinfo);
1601 n = V_tcbinfo.ipi_count;
1602 INP_INFO_WUNLOCK(&V_tcbinfo);
1603 if (n == 0)
1604 break;
1605 pause("tcpdes", hz / 10);
1606 }
1607 tcp_hc_destroy();
1608 syncache_destroy();
1609 in_pcbinfo_destroy(&V_tcbinfo);
1610 /* tcp_discardcb() clears the sack_holes up. */
1611 uma_zdestroy(V_sack_hole_zone);
1612
1613 /*
1614 * Cannot free the zone until all tcpcbs are released as we attach
1615 * the allocations to them.
1616 */
1617 tcp_fastopen_destroy();
1618
1619 COUNTER_ARRAY_FREE(V_tcps_states, TCP_NSTATES);
1620 VNET_PCPUSTAT_FREE(tcpstat);
1621
1622 #ifdef TCP_HHOOK
1623 error = hhook_head_deregister(V_tcp_hhh[HHOOK_TCP_EST_IN]);
1624 if (error != 0) {
1625 printf("%s: WARNING: unable to deregister helper hook "
1626 "type=%d, id=%d: error %d returned\n", __func__,
1627 HHOOK_TYPE_TCP, HHOOK_TCP_EST_IN, error);
1628 }
1629 error = hhook_head_deregister(V_tcp_hhh[HHOOK_TCP_EST_OUT]);
1630 if (error != 0) {
1631 printf("%s: WARNING: unable to deregister helper hook "
1632 "type=%d, id=%d: error %d returned\n", __func__,
1633 HHOOK_TYPE_TCP, HHOOK_TCP_EST_OUT, error);
1634 }
1635 #endif
1636 }
1637 VNET_SYSUNINIT(tcp, SI_SUB_PROTO_DOMAIN, SI_ORDER_FOURTH, tcp_destroy, NULL);
1638 #endif
1639
1640 void
tcp_fini(void * xtp)1641 tcp_fini(void *xtp)
1642 {
1643
1644 }
1645
1646 /*
1647 * Fill in the IP and TCP headers for an outgoing packet, given the tcpcb.
1648 * tcp_template used to store this data in mbufs, but we now recopy it out
1649 * of the tcpcb each time to conserve mbufs.
1650 */
1651 void
tcpip_fillheaders(struct inpcb * inp,uint16_t port,void * ip_ptr,void * tcp_ptr)1652 tcpip_fillheaders(struct inpcb *inp, uint16_t port, void *ip_ptr, void *tcp_ptr)
1653 {
1654 struct tcphdr *th = (struct tcphdr *)tcp_ptr;
1655
1656 INP_WLOCK_ASSERT(inp);
1657
1658 #ifdef INET6
1659 if ((inp->inp_vflag & INP_IPV6) != 0) {
1660 struct ip6_hdr *ip6;
1661
1662 ip6 = (struct ip6_hdr *)ip_ptr;
1663 ip6->ip6_flow = (ip6->ip6_flow & ~IPV6_FLOWINFO_MASK) |
1664 (inp->inp_flow & IPV6_FLOWINFO_MASK);
1665 ip6->ip6_vfc = (ip6->ip6_vfc & ~IPV6_VERSION_MASK) |
1666 (IPV6_VERSION & IPV6_VERSION_MASK);
1667 if (port == 0)
1668 ip6->ip6_nxt = IPPROTO_TCP;
1669 else
1670 ip6->ip6_nxt = IPPROTO_UDP;
1671 ip6->ip6_plen = htons(sizeof(struct tcphdr));
1672 ip6->ip6_src = inp->in6p_laddr;
1673 ip6->ip6_dst = inp->in6p_faddr;
1674 }
1675 #endif /* INET6 */
1676 #if defined(INET6) && defined(INET)
1677 else
1678 #endif
1679 #ifdef INET
1680 {
1681 struct ip *ip;
1682
1683 ip = (struct ip *)ip_ptr;
1684 ip->ip_v = IPVERSION;
1685 ip->ip_hl = 5;
1686 ip->ip_tos = inp->inp_ip_tos;
1687 ip->ip_len = 0;
1688 ip->ip_id = 0;
1689 ip->ip_off = 0;
1690 ip->ip_ttl = inp->inp_ip_ttl;
1691 ip->ip_sum = 0;
1692 if (port == 0)
1693 ip->ip_p = IPPROTO_TCP;
1694 else
1695 ip->ip_p = IPPROTO_UDP;
1696 ip->ip_src = inp->inp_laddr;
1697 ip->ip_dst = inp->inp_faddr;
1698 }
1699 #endif /* INET */
1700 th->th_sport = inp->inp_lport;
1701 th->th_dport = inp->inp_fport;
1702 th->th_seq = 0;
1703 th->th_ack = 0;
1704 th->th_off = 5;
1705 tcp_set_flags(th, 0);
1706 th->th_win = 0;
1707 th->th_urp = 0;
1708 th->th_sum = 0; /* in_pseudo() is called later for ipv4 */
1709 }
1710
1711 /*
1712 * Create template to be used to send tcp packets on a connection.
1713 * Allocates an mbuf and fills in a skeletal tcp/ip header. The only
1714 * use for this function is in keepalives, which use tcp_respond.
1715 */
1716 struct tcptemp *
tcpip_maketemplate(struct inpcb * inp)1717 tcpip_maketemplate(struct inpcb *inp)
1718 {
1719 struct tcptemp *t;
1720
1721 t = malloc(sizeof(*t), M_TEMP, M_NOWAIT);
1722 if (t == NULL)
1723 return (NULL);
1724 tcpip_fillheaders(inp, 0, (void *)&t->tt_ipgen, (void *)&t->tt_t);
1725 return (t);
1726 }
1727
1728 /*
1729 * Send a single message to the TCP at address specified by
1730 * the given TCP/IP header. If m == NULL, then we make a copy
1731 * of the tcpiphdr at th and send directly to the addressed host.
1732 * This is used to force keep alive messages out using the TCP
1733 * template for a connection. If flags are given then we send
1734 * a message back to the TCP which originated the segment th,
1735 * and discard the mbuf containing it and any other attached mbufs.
1736 *
1737 * In any case the ack and sequence number of the transmitted
1738 * segment are as specified by the parameters.
1739 *
1740 * NOTE: If m != NULL, then th must point to *inside* the mbuf.
1741 */
1742
1743 void
tcp_respond(struct tcpcb * tp,void * ipgen,struct tcphdr * th,struct mbuf * m,tcp_seq ack,tcp_seq seq,uint16_t flags)1744 tcp_respond(struct tcpcb *tp, void *ipgen, struct tcphdr *th, struct mbuf *m,
1745 tcp_seq ack, tcp_seq seq, uint16_t flags)
1746 {
1747 struct tcpopt to;
1748 struct inpcb *inp;
1749 struct ip *ip;
1750 struct mbuf *optm;
1751 struct udphdr *uh = NULL;
1752 struct tcphdr *nth;
1753 struct tcp_log_buffer *lgb;
1754 u_char *optp;
1755 #ifdef INET6
1756 struct ip6_hdr *ip6;
1757 int isipv6;
1758 #endif /* INET6 */
1759 int optlen, tlen, win, ulen;
1760 int ect = 0;
1761 bool incl_opts;
1762 uint16_t port;
1763 int output_ret;
1764 #ifdef INVARIANTS
1765 int thflags = tcp_get_flags(th);
1766 #endif
1767
1768 KASSERT(tp != NULL || m != NULL, ("tcp_respond: tp and m both NULL"));
1769 NET_EPOCH_ASSERT();
1770
1771 #ifdef INET6
1772 isipv6 = ((struct ip *)ipgen)->ip_v == (IPV6_VERSION >> 4);
1773 ip6 = ipgen;
1774 #endif /* INET6 */
1775 ip = ipgen;
1776
1777 if (tp != NULL) {
1778 inp = tptoinpcb(tp);
1779 INP_LOCK_ASSERT(inp);
1780 } else
1781 inp = NULL;
1782
1783 if (m != NULL) {
1784 #ifdef INET6
1785 if (isipv6 && ip6 && (ip6->ip6_nxt == IPPROTO_UDP))
1786 port = m->m_pkthdr.tcp_tun_port;
1787 else
1788 #endif
1789 if (ip && (ip->ip_p == IPPROTO_UDP))
1790 port = m->m_pkthdr.tcp_tun_port;
1791 else
1792 port = 0;
1793 } else
1794 port = tp->t_port;
1795
1796 incl_opts = false;
1797 win = 0;
1798 if (tp != NULL) {
1799 if (!(flags & TH_RST)) {
1800 win = sbspace(&inp->inp_socket->so_rcv);
1801 if (win > TCP_MAXWIN << tp->rcv_scale)
1802 win = TCP_MAXWIN << tp->rcv_scale;
1803 }
1804 if ((tp->t_flags & TF_NOOPT) == 0)
1805 incl_opts = true;
1806 }
1807 if (m == NULL) {
1808 m = m_gethdr(M_NOWAIT, MT_DATA);
1809 if (m == NULL)
1810 return;
1811 m->m_data += max_linkhdr;
1812 #ifdef INET6
1813 if (isipv6) {
1814 bcopy((caddr_t)ip6, mtod(m, caddr_t),
1815 sizeof(struct ip6_hdr));
1816 ip6 = mtod(m, struct ip6_hdr *);
1817 nth = (struct tcphdr *)(ip6 + 1);
1818 if (port) {
1819 /* Insert a UDP header */
1820 uh = (struct udphdr *)nth;
1821 uh->uh_sport = htons(V_tcp_udp_tunneling_port);
1822 uh->uh_dport = port;
1823 nth = (struct tcphdr *)(uh + 1);
1824 }
1825 } else
1826 #endif /* INET6 */
1827 {
1828 bcopy((caddr_t)ip, mtod(m, caddr_t), sizeof(struct ip));
1829 ip = mtod(m, struct ip *);
1830 nth = (struct tcphdr *)(ip + 1);
1831 if (port) {
1832 /* Insert a UDP header */
1833 uh = (struct udphdr *)nth;
1834 uh->uh_sport = htons(V_tcp_udp_tunneling_port);
1835 uh->uh_dport = port;
1836 nth = (struct tcphdr *)(uh + 1);
1837 }
1838 }
1839 bcopy((caddr_t)th, (caddr_t)nth, sizeof(struct tcphdr));
1840 flags = TH_ACK;
1841 } else if ((!M_WRITABLE(m)) || (port != 0)) {
1842 struct mbuf *n;
1843
1844 /* Can't reuse 'm', allocate a new mbuf. */
1845 n = m_gethdr(M_NOWAIT, MT_DATA);
1846 if (n == NULL) {
1847 m_freem(m);
1848 return;
1849 }
1850
1851 if (!m_dup_pkthdr(n, m, M_NOWAIT)) {
1852 m_freem(m);
1853 m_freem(n);
1854 return;
1855 }
1856
1857 n->m_data += max_linkhdr;
1858 /* m_len is set later */
1859 #define xchg(a,b,type) { type t; t=a; a=b; b=t; }
1860 #ifdef INET6
1861 if (isipv6) {
1862 bcopy((caddr_t)ip6, mtod(n, caddr_t),
1863 sizeof(struct ip6_hdr));
1864 ip6 = mtod(n, struct ip6_hdr *);
1865 xchg(ip6->ip6_dst, ip6->ip6_src, struct in6_addr);
1866 nth = (struct tcphdr *)(ip6 + 1);
1867 if (port) {
1868 /* Insert a UDP header */
1869 uh = (struct udphdr *)nth;
1870 uh->uh_sport = htons(V_tcp_udp_tunneling_port);
1871 uh->uh_dport = port;
1872 nth = (struct tcphdr *)(uh + 1);
1873 }
1874 } else
1875 #endif /* INET6 */
1876 {
1877 bcopy((caddr_t)ip, mtod(n, caddr_t), sizeof(struct ip));
1878 ip = mtod(n, struct ip *);
1879 xchg(ip->ip_dst.s_addr, ip->ip_src.s_addr, uint32_t);
1880 nth = (struct tcphdr *)(ip + 1);
1881 if (port) {
1882 /* Insert a UDP header */
1883 uh = (struct udphdr *)nth;
1884 uh->uh_sport = htons(V_tcp_udp_tunneling_port);
1885 uh->uh_dport = port;
1886 nth = (struct tcphdr *)(uh + 1);
1887 }
1888 }
1889 bcopy((caddr_t)th, (caddr_t)nth, sizeof(struct tcphdr));
1890 xchg(nth->th_dport, nth->th_sport, uint16_t);
1891 th = nth;
1892 m_freem(m);
1893 m = n;
1894 } else {
1895 /*
1896 * reuse the mbuf.
1897 * XXX MRT We inherit the FIB, which is lucky.
1898 */
1899 m_freem(m->m_next);
1900 m->m_next = NULL;
1901 m->m_data = (caddr_t)ipgen;
1902 /* clear any receive flags for proper bpf timestamping */
1903 m->m_flags &= ~(M_TSTMP | M_TSTMP_LRO);
1904 /* m_len is set later */
1905 #ifdef INET6
1906 if (isipv6) {
1907 xchg(ip6->ip6_dst, ip6->ip6_src, struct in6_addr);
1908 nth = (struct tcphdr *)(ip6 + 1);
1909 } else
1910 #endif /* INET6 */
1911 {
1912 xchg(ip->ip_dst.s_addr, ip->ip_src.s_addr, uint32_t);
1913 nth = (struct tcphdr *)(ip + 1);
1914 }
1915 if (th != nth) {
1916 /*
1917 * this is usually a case when an extension header
1918 * exists between the IPv6 header and the
1919 * TCP header.
1920 */
1921 nth->th_sport = th->th_sport;
1922 nth->th_dport = th->th_dport;
1923 }
1924 xchg(nth->th_dport, nth->th_sport, uint16_t);
1925 #undef xchg
1926 }
1927 tlen = 0;
1928 #ifdef INET6
1929 if (isipv6)
1930 tlen = sizeof (struct ip6_hdr) + sizeof (struct tcphdr);
1931 #endif
1932 #if defined(INET) && defined(INET6)
1933 else
1934 #endif
1935 #ifdef INET
1936 tlen = sizeof (struct tcpiphdr);
1937 #endif
1938 if (port)
1939 tlen += sizeof (struct udphdr);
1940 #ifdef INVARIANTS
1941 m->m_len = 0;
1942 KASSERT(M_TRAILINGSPACE(m) >= tlen,
1943 ("Not enough trailing space for message (m=%p, need=%d, have=%ld)",
1944 m, tlen, (long)M_TRAILINGSPACE(m)));
1945 #endif
1946 m->m_len = tlen;
1947 to.to_flags = 0;
1948 if (incl_opts) {
1949 ect = tcp_ecn_output_established(tp, &flags, 0, false);
1950 /* Make sure we have room. */
1951 if (M_TRAILINGSPACE(m) < TCP_MAXOLEN) {
1952 m->m_next = m_get(M_NOWAIT, MT_DATA);
1953 if (m->m_next) {
1954 optp = mtod(m->m_next, u_char *);
1955 optm = m->m_next;
1956 } else
1957 incl_opts = false;
1958 } else {
1959 optp = (u_char *) (nth + 1);
1960 optm = m;
1961 }
1962 }
1963 if (incl_opts) {
1964 /* Timestamps. */
1965 if (tp->t_flags & TF_RCVD_TSTMP) {
1966 to.to_tsval = tcp_ts_getticks() + tp->ts_offset;
1967 to.to_tsecr = tp->ts_recent;
1968 to.to_flags |= TOF_TS;
1969 }
1970 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE)
1971 /* TCP-MD5 (RFC2385). */
1972 if (tp->t_flags & TF_SIGNATURE)
1973 to.to_flags |= TOF_SIGNATURE;
1974 #endif
1975 /* Add the options. */
1976 tlen += optlen = tcp_addoptions(&to, optp);
1977
1978 /* Update m_len in the correct mbuf. */
1979 optm->m_len += optlen;
1980 } else
1981 optlen = 0;
1982 #ifdef INET6
1983 if (isipv6) {
1984 if (uh) {
1985 ulen = tlen - sizeof(struct ip6_hdr);
1986 uh->uh_ulen = htons(ulen);
1987 }
1988 ip6->ip6_flow = htonl(ect << IPV6_FLOWLABEL_LEN);
1989 ip6->ip6_vfc = IPV6_VERSION;
1990 if (port)
1991 ip6->ip6_nxt = IPPROTO_UDP;
1992 else
1993 ip6->ip6_nxt = IPPROTO_TCP;
1994 ip6->ip6_plen = htons(tlen - sizeof(*ip6));
1995 }
1996 #endif
1997 #if defined(INET) && defined(INET6)
1998 else
1999 #endif
2000 #ifdef INET
2001 {
2002 if (uh) {
2003 ulen = tlen - sizeof(struct ip);
2004 uh->uh_ulen = htons(ulen);
2005 }
2006 ip->ip_len = htons(tlen);
2007 if (inp != NULL) {
2008 ip->ip_tos = inp->inp_ip_tos & ~IPTOS_ECN_MASK;
2009 ip->ip_ttl = inp->inp_ip_ttl;
2010 } else {
2011 ip->ip_tos = 0;
2012 ip->ip_ttl = V_ip_defttl;
2013 }
2014 ip->ip_tos |= ect;
2015 if (port) {
2016 ip->ip_p = IPPROTO_UDP;
2017 } else {
2018 ip->ip_p = IPPROTO_TCP;
2019 }
2020 if (V_path_mtu_discovery)
2021 ip->ip_off |= htons(IP_DF);
2022 }
2023 #endif
2024 m->m_pkthdr.len = tlen;
2025 m->m_pkthdr.rcvif = NULL;
2026 #ifdef MAC
2027 if (inp != NULL) {
2028 /*
2029 * Packet is associated with a socket, so allow the
2030 * label of the response to reflect the socket label.
2031 */
2032 INP_LOCK_ASSERT(inp);
2033 mac_inpcb_create_mbuf(inp, m);
2034 } else {
2035 /*
2036 * Packet is not associated with a socket, so possibly
2037 * update the label in place.
2038 */
2039 mac_netinet_tcp_reply(m);
2040 }
2041 #endif
2042 nth->th_seq = htonl(seq);
2043 nth->th_ack = htonl(ack);
2044 nth->th_off = (sizeof (struct tcphdr) + optlen) >> 2;
2045 tcp_set_flags(nth, flags);
2046 if (tp && (flags & TH_RST)) {
2047 /* Log the reset */
2048 tcp_log_end_status(tp, TCP_EI_STATUS_SERVER_RST);
2049 }
2050 if (tp != NULL)
2051 nth->th_win = htons((u_short) (win >> tp->rcv_scale));
2052 else
2053 nth->th_win = htons((u_short)win);
2054 nth->th_urp = 0;
2055
2056 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE)
2057 if (to.to_flags & TOF_SIGNATURE) {
2058 if (!TCPMD5_ENABLED() ||
2059 TCPMD5_OUTPUT(m, nth, to.to_signature) != 0) {
2060 m_freem(m);
2061 return;
2062 }
2063 }
2064 #endif
2065
2066 #ifdef INET6
2067 if (isipv6) {
2068 if (port) {
2069 m->m_pkthdr.csum_flags = CSUM_UDP_IPV6;
2070 m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum);
2071 uh->uh_sum = in6_cksum_pseudo(ip6, ulen, IPPROTO_UDP, 0);
2072 nth->th_sum = 0;
2073 } else {
2074 m->m_pkthdr.csum_flags = CSUM_TCP_IPV6;
2075 m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum);
2076 nth->th_sum = in6_cksum_pseudo(ip6,
2077 tlen - sizeof(struct ip6_hdr), IPPROTO_TCP, 0);
2078 }
2079 ip6->ip6_hlim = in6_selecthlim(inp, NULL);
2080 }
2081 #endif /* INET6 */
2082 #if defined(INET6) && defined(INET)
2083 else
2084 #endif
2085 #ifdef INET
2086 {
2087 if (port) {
2088 uh->uh_sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr,
2089 htons(ulen + IPPROTO_UDP));
2090 m->m_pkthdr.csum_flags = CSUM_UDP;
2091 m->m_pkthdr.csum_data = offsetof(struct udphdr, uh_sum);
2092 nth->th_sum = 0;
2093 } else {
2094 m->m_pkthdr.csum_flags = CSUM_TCP;
2095 m->m_pkthdr.csum_data = offsetof(struct tcphdr, th_sum);
2096 nth->th_sum = in_pseudo(ip->ip_src.s_addr, ip->ip_dst.s_addr,
2097 htons((u_short)(tlen - sizeof(struct ip) + ip->ip_p)));
2098 }
2099 }
2100 #endif /* INET */
2101 TCP_PROBE3(debug__output, tp, th, m);
2102 if (flags & TH_RST)
2103 TCP_PROBE5(accept__refused, NULL, NULL, m, tp, nth);
2104 lgb = NULL;
2105 if ((tp != NULL) && tcp_bblogging_on(tp)) {
2106 if (INP_WLOCKED(inp)) {
2107 union tcp_log_stackspecific log;
2108 struct timeval tv;
2109
2110 memset(&log.u_bbr, 0, sizeof(log.u_bbr));
2111 log.u_bbr.inhpts = tcp_in_hpts(tp);
2112 log.u_bbr.flex8 = 4;
2113 log.u_bbr.pkts_out = tp->t_maxseg;
2114 log.u_bbr.timeStamp = tcp_get_usecs(&tv);
2115 log.u_bbr.delivered = 0;
2116 lgb = tcp_log_event(tp, nth, NULL, NULL, TCP_LOG_OUT,
2117 ERRNO_UNK, 0, &log, false, NULL, NULL, 0, &tv);
2118 } else {
2119 /*
2120 * We can not log the packet, since we only own the
2121 * read lock, but a write lock is needed. The read lock
2122 * is not upgraded to a write lock, since only getting
2123 * the read lock was done intentionally to improve the
2124 * handling of SYN flooding attacks.
2125 * This happens only for pure SYN segments received in
2126 * the initial CLOSED state, or received in a more
2127 * advanced state than listen and the UDP encapsulation
2128 * port is unexpected.
2129 * The incoming SYN segments do not really belong to
2130 * the TCP connection and the handling does not change
2131 * the state of the TCP connection. Therefore, the
2132 * sending of the RST segments is not logged. Please
2133 * note that also the incoming SYN segments are not
2134 * logged.
2135 *
2136 * The following code ensures that the above description
2137 * is and stays correct.
2138 */
2139 KASSERT((thflags & (TH_ACK|TH_SYN)) == TH_SYN &&
2140 (tp->t_state == TCPS_CLOSED ||
2141 (tp->t_state > TCPS_LISTEN && tp->t_port != port)),
2142 ("%s: Logging of TCP segment with flags 0x%b and "
2143 "UDP encapsulation port %u skipped in state %s",
2144 __func__, thflags, PRINT_TH_FLAGS,
2145 ntohs(port), tcpstates[tp->t_state]));
2146 }
2147 }
2148
2149 if (flags & TH_ACK)
2150 TCPSTAT_INC(tcps_sndacks);
2151 else if (flags & (TH_SYN|TH_FIN|TH_RST))
2152 TCPSTAT_INC(tcps_sndctrl);
2153 TCPSTAT_INC(tcps_sndtotal);
2154
2155 #ifdef INET6
2156 if (isipv6) {
2157 TCP_PROBE5(send, NULL, tp, ip6, tp, nth);
2158 output_ret = ip6_output(m, inp ? inp->in6p_outputopts : NULL,
2159 NULL, 0, NULL, NULL, inp);
2160 }
2161 #endif /* INET6 */
2162 #if defined(INET) && defined(INET6)
2163 else
2164 #endif
2165 #ifdef INET
2166 {
2167 TCP_PROBE5(send, NULL, tp, ip, tp, nth);
2168 output_ret = ip_output(m, NULL, NULL, 0, NULL, inp);
2169 }
2170 #endif
2171 if (lgb != NULL)
2172 lgb->tlb_errno = output_ret;
2173 }
2174
2175 /*
2176 * Create a new TCP control block, making an empty reassembly queue and hooking
2177 * it to the argument protocol control block. The `inp' parameter must have
2178 * come from the zone allocator set up by tcpcbstor declaration.
2179 */
2180 struct tcpcb *
tcp_newtcpcb(struct inpcb * inp)2181 tcp_newtcpcb(struct inpcb *inp)
2182 {
2183 struct tcpcb *tp = intotcpcb(inp);
2184 #ifdef INET6
2185 int isipv6 = (inp->inp_vflag & INP_IPV6) != 0;
2186 #endif /* INET6 */
2187
2188 /*
2189 * Historically allocation was done with M_ZERO. There is a lot of
2190 * code that rely on that. For now take safe approach and zero whole
2191 * tcpcb. This definitely can be optimized.
2192 */
2193 bzero(&tp->t_start_zero, t_zero_size);
2194
2195 /* Initialise cc_var struct for this tcpcb. */
2196 tp->t_ccv.type = IPPROTO_TCP;
2197 tp->t_ccv.ccvc.tcp = tp;
2198 rw_rlock(&tcp_function_lock);
2199 tp->t_fb = V_tcp_func_set_ptr;
2200 refcount_acquire(&tp->t_fb->tfb_refcnt);
2201 rw_runlock(&tcp_function_lock);
2202 /*
2203 * Use the current system default CC algorithm.
2204 */
2205 cc_attach(tp, CC_DEFAULT_ALGO());
2206
2207 if (CC_ALGO(tp)->cb_init != NULL)
2208 if (CC_ALGO(tp)->cb_init(&tp->t_ccv, NULL) > 0) {
2209 cc_detach(tp);
2210 if (tp->t_fb->tfb_tcp_fb_fini)
2211 (*tp->t_fb->tfb_tcp_fb_fini)(tp, 1);
2212 refcount_release(&tp->t_fb->tfb_refcnt);
2213 return (NULL);
2214 }
2215
2216 #ifdef TCP_HHOOK
2217 if (khelp_init_osd(HELPER_CLASS_TCP, &tp->t_osd)) {
2218 if (tp->t_fb->tfb_tcp_fb_fini)
2219 (*tp->t_fb->tfb_tcp_fb_fini)(tp, 1);
2220 refcount_release(&tp->t_fb->tfb_refcnt);
2221 return (NULL);
2222 }
2223 #endif
2224
2225 TAILQ_INIT(&tp->t_segq);
2226 STAILQ_INIT(&tp->t_inqueue);
2227 tp->t_maxseg =
2228 #ifdef INET6
2229 isipv6 ? V_tcp_v6mssdflt :
2230 #endif /* INET6 */
2231 V_tcp_mssdflt;
2232
2233 /* All mbuf queue/ack compress flags should be off */
2234 tcp_lro_features_off(tp);
2235
2236 tp->t_hpts_cpu = HPTS_CPU_NONE;
2237 tp->t_lro_cpu = HPTS_CPU_NONE;
2238
2239 callout_init_rw(&tp->t_callout, &inp->inp_lock, CALLOUT_RETURNUNLOCKED);
2240 for (int i = 0; i < TT_N; i++)
2241 tp->t_timers[i] = SBT_MAX;
2242
2243 switch (V_tcp_do_rfc1323) {
2244 case 0:
2245 break;
2246 default:
2247 case 1:
2248 tp->t_flags = (TF_REQ_SCALE|TF_REQ_TSTMP);
2249 break;
2250 case 2:
2251 tp->t_flags = TF_REQ_SCALE;
2252 break;
2253 case 3:
2254 tp->t_flags = TF_REQ_TSTMP;
2255 break;
2256 }
2257 if (V_tcp_do_sack)
2258 tp->t_flags |= TF_SACK_PERMIT;
2259 TAILQ_INIT(&tp->snd_holes);
2260
2261 /*
2262 * Init srtt to TCPTV_SRTTBASE (0), so we can tell that we have no
2263 * rtt estimate. Set rttvar so that srtt + 4 * rttvar gives
2264 * reasonable initial retransmit time.
2265 */
2266 tp->t_srtt = TCPTV_SRTTBASE;
2267 tp->t_rttvar = ((tcp_rexmit_initial - TCPTV_SRTTBASE) << TCP_RTTVAR_SHIFT) / 4;
2268 tp->t_rttmin = tcp_rexmit_min;
2269 tp->t_rxtcur = tcp_rexmit_initial;
2270 tp->snd_cwnd = TCP_MAXWIN << TCP_MAX_WINSHIFT;
2271 tp->snd_ssthresh = TCP_MAXWIN << TCP_MAX_WINSHIFT;
2272 tp->t_rcvtime = ticks;
2273 /* We always start with ticks granularity */
2274 tp->t_tmr_granularity = TCP_TMR_GRANULARITY_TICKS;
2275 /*
2276 * IPv4 TTL initialization is necessary for an IPv6 socket as well,
2277 * because the socket may be bound to an IPv6 wildcard address,
2278 * which may match an IPv4-mapped IPv6 address.
2279 */
2280 inp->inp_ip_ttl = V_ip_defttl;
2281 #ifdef TCPPCAP
2282 /*
2283 * Init the TCP PCAP queues.
2284 */
2285 tcp_pcap_tcpcb_init(tp);
2286 #endif
2287 #ifdef TCP_BLACKBOX
2288 /* Initialize the per-TCPCB log data. */
2289 tcp_log_tcpcbinit(tp);
2290 #endif
2291 tp->t_pacing_rate = -1;
2292 if (tp->t_fb->tfb_tcp_fb_init) {
2293 if ((*tp->t_fb->tfb_tcp_fb_init)(tp, &tp->t_fb_ptr)) {
2294 refcount_release(&tp->t_fb->tfb_refcnt);
2295 return (NULL);
2296 }
2297 }
2298 #ifdef STATS
2299 if (V_tcp_perconn_stats_enable == 1)
2300 tp->t_stats = stats_blob_alloc(V_tcp_perconn_stats_dflt_tpl, 0);
2301 #endif
2302 if (V_tcp_do_lrd)
2303 tp->t_flags |= TF_LRD;
2304
2305 return (tp);
2306 }
2307
2308 /*
2309 * Drop a TCP connection, reporting
2310 * the specified error. If connection is synchronized,
2311 * then send a RST to peer.
2312 */
2313 struct tcpcb *
tcp_drop(struct tcpcb * tp,int errno)2314 tcp_drop(struct tcpcb *tp, int errno)
2315 {
2316 struct socket *so = tptosocket(tp);
2317
2318 NET_EPOCH_ASSERT();
2319 INP_WLOCK_ASSERT(tptoinpcb(tp));
2320
2321 if (TCPS_HAVERCVDSYN(tp->t_state)) {
2322 tcp_state_change(tp, TCPS_CLOSED);
2323 /* Don't use tcp_output() here due to possible recursion. */
2324 (void)tcp_output_nodrop(tp);
2325 TCPSTAT_INC(tcps_drops);
2326 } else
2327 TCPSTAT_INC(tcps_conndrops);
2328 if (errno == ETIMEDOUT && tp->t_softerror)
2329 errno = tp->t_softerror;
2330 so->so_error = errno;
2331 return (tcp_close(tp));
2332 }
2333
2334 void
tcp_discardcb(struct tcpcb * tp)2335 tcp_discardcb(struct tcpcb *tp)
2336 {
2337 struct inpcb *inp = tptoinpcb(tp);
2338 struct socket *so = tptosocket(tp);
2339 struct mbuf *m;
2340 #ifdef INET6
2341 bool isipv6 = (inp->inp_vflag & INP_IPV6) != 0;
2342 #endif
2343
2344 INP_WLOCK_ASSERT(inp);
2345 MPASS(!callout_active(&tp->t_callout));
2346 MPASS(TAILQ_EMPTY(&tp->snd_holes));
2347
2348 /* free the reassembly queue, if any */
2349 tcp_reass_flush(tp);
2350
2351 #ifdef TCP_OFFLOAD
2352 /* Disconnect offload device, if any. */
2353 if (tp->t_flags & TF_TOE)
2354 tcp_offload_detach(tp);
2355 #endif
2356 #ifdef TCPPCAP
2357 /* Free the TCP PCAP queues. */
2358 tcp_pcap_drain(&(tp->t_inpkts));
2359 tcp_pcap_drain(&(tp->t_outpkts));
2360 #endif
2361
2362 /* Allow the CC algorithm to clean up after itself. */
2363 if (CC_ALGO(tp)->cb_destroy != NULL)
2364 CC_ALGO(tp)->cb_destroy(&tp->t_ccv);
2365 CC_DATA(tp) = NULL;
2366 /* Detach from the CC algorithm */
2367 cc_detach(tp);
2368
2369 #ifdef TCP_HHOOK
2370 khelp_destroy_osd(&tp->t_osd);
2371 #endif
2372 #ifdef STATS
2373 stats_blob_destroy(tp->t_stats);
2374 #endif
2375
2376 CC_ALGO(tp) = NULL;
2377 if ((m = STAILQ_FIRST(&tp->t_inqueue)) != NULL) {
2378 struct mbuf *prev;
2379
2380 STAILQ_INIT(&tp->t_inqueue);
2381 STAILQ_FOREACH_FROM_SAFE(m, &tp->t_inqueue, m_stailqpkt, prev)
2382 m_freem(m);
2383 }
2384 TCPSTATES_DEC(tp->t_state);
2385
2386 if (tp->t_fb->tfb_tcp_fb_fini)
2387 (*tp->t_fb->tfb_tcp_fb_fini)(tp, 1);
2388 MPASS(!tcp_in_hpts(tp));
2389 #ifdef TCP_BLACKBOX
2390 tcp_log_tcpcbfini(tp);
2391 #endif
2392
2393 /*
2394 * If we got enough samples through the srtt filter,
2395 * save the rtt and rttvar in the routing entry.
2396 * 'Enough' is arbitrarily defined as 4 rtt samples.
2397 * 4 samples is enough for the srtt filter to converge
2398 * to within enough % of the correct value; fewer samples
2399 * and we could save a bogus rtt. The danger is not high
2400 * as tcp quickly recovers from everything.
2401 * XXX: Works very well but needs some more statistics!
2402 *
2403 * XXXRRS: Updating must be after the stack fini() since
2404 * that may be converting some internal representation of
2405 * say srtt etc into the general one used by other stacks.
2406 * Lets also at least protect against the so being NULL
2407 * as RW stated below.
2408 */
2409 if ((tp->t_rttupdated >= 4) && (so != NULL)) {
2410 struct hc_metrics_lite metrics;
2411 uint32_t ssthresh;
2412
2413 bzero(&metrics, sizeof(metrics));
2414 /*
2415 * Update the ssthresh always when the conditions below
2416 * are satisfied. This gives us better new start value
2417 * for the congestion avoidance for new connections.
2418 * ssthresh is only set if packet loss occurred on a session.
2419 *
2420 * XXXRW: 'so' may be NULL here, and/or socket buffer may be
2421 * being torn down. Ideally this code would not use 'so'.
2422 */
2423 ssthresh = tp->snd_ssthresh;
2424 if (ssthresh != 0 && ssthresh < so->so_snd.sb_hiwat / 2) {
2425 /*
2426 * convert the limit from user data bytes to
2427 * packets then to packet data bytes.
2428 */
2429 ssthresh = (ssthresh + tp->t_maxseg / 2) / tp->t_maxseg;
2430 if (ssthresh < 2)
2431 ssthresh = 2;
2432 ssthresh *= (tp->t_maxseg +
2433 #ifdef INET6
2434 (isipv6 ? sizeof (struct ip6_hdr) +
2435 sizeof (struct tcphdr) :
2436 #endif
2437 sizeof (struct tcpiphdr)
2438 #ifdef INET6
2439 )
2440 #endif
2441 );
2442 } else
2443 ssthresh = 0;
2444 metrics.rmx_ssthresh = ssthresh;
2445
2446 metrics.rmx_rtt = tp->t_srtt;
2447 metrics.rmx_rttvar = tp->t_rttvar;
2448 metrics.rmx_cwnd = tp->snd_cwnd;
2449 metrics.rmx_sendpipe = 0;
2450 metrics.rmx_recvpipe = 0;
2451
2452 tcp_hc_update(&inp->inp_inc, &metrics);
2453 }
2454
2455 refcount_release(&tp->t_fb->tfb_refcnt);
2456 }
2457
2458 /*
2459 * Attempt to close a TCP control block, marking it as dropped, and freeing
2460 * the socket if we hold the only reference.
2461 */
2462 struct tcpcb *
tcp_close(struct tcpcb * tp)2463 tcp_close(struct tcpcb *tp)
2464 {
2465 struct inpcb *inp = tptoinpcb(tp);
2466 struct socket *so = tptosocket(tp);
2467
2468 INP_WLOCK_ASSERT(inp);
2469
2470 #ifdef TCP_OFFLOAD
2471 if (tp->t_state == TCPS_LISTEN)
2472 tcp_offload_listen_stop(tp);
2473 #endif
2474 /*
2475 * This releases the TFO pending counter resource for TFO listen
2476 * sockets as well as passively-created TFO sockets that transition
2477 * from SYN_RECEIVED to CLOSED.
2478 */
2479 if (tp->t_tfo_pending) {
2480 tcp_fastopen_decrement_counter(tp->t_tfo_pending);
2481 tp->t_tfo_pending = NULL;
2482 }
2483 tcp_timer_stop(tp);
2484 if (tp->t_fb->tfb_tcp_timer_stop_all != NULL)
2485 tp->t_fb->tfb_tcp_timer_stop_all(tp);
2486 in_pcbdrop(inp);
2487 TCPSTAT_INC(tcps_closed);
2488 if (tp->t_state != TCPS_CLOSED)
2489 tcp_state_change(tp, TCPS_CLOSED);
2490 KASSERT(inp->inp_socket != NULL, ("tcp_close: inp_socket NULL"));
2491 tcp_free_sackholes(tp);
2492 soisdisconnected(so);
2493 if (inp->inp_flags & INP_SOCKREF) {
2494 inp->inp_flags &= ~INP_SOCKREF;
2495 INP_WUNLOCK(inp);
2496 sorele(so);
2497 return (NULL);
2498 }
2499 return (tp);
2500 }
2501
2502 /*
2503 * Notify a tcp user of an asynchronous error;
2504 * store error as soft error, but wake up user
2505 * (for now, won't do anything until can select for soft error).
2506 *
2507 * Do not wake up user since there currently is no mechanism for
2508 * reporting soft errors (yet - a kqueue filter may be added).
2509 */
2510 static struct inpcb *
tcp_notify(struct inpcb * inp,int error)2511 tcp_notify(struct inpcb *inp, int error)
2512 {
2513 struct tcpcb *tp;
2514
2515 INP_WLOCK_ASSERT(inp);
2516
2517 tp = intotcpcb(inp);
2518 KASSERT(tp != NULL, ("tcp_notify: tp == NULL"));
2519
2520 /*
2521 * Ignore some errors if we are hooked up.
2522 * If connection hasn't completed, has retransmitted several times,
2523 * and receives a second error, give up now. This is better
2524 * than waiting a long time to establish a connection that
2525 * can never complete.
2526 */
2527 if (tp->t_state == TCPS_ESTABLISHED &&
2528 (error == EHOSTUNREACH || error == ENETUNREACH ||
2529 error == EHOSTDOWN)) {
2530 if (inp->inp_route.ro_nh) {
2531 NH_FREE(inp->inp_route.ro_nh);
2532 inp->inp_route.ro_nh = (struct nhop_object *)NULL;
2533 }
2534 return (inp);
2535 } else if (tp->t_state < TCPS_ESTABLISHED && tp->t_rxtshift > 3 &&
2536 tp->t_softerror) {
2537 tp = tcp_drop(tp, error);
2538 if (tp != NULL)
2539 return (inp);
2540 else
2541 return (NULL);
2542 } else {
2543 tp->t_softerror = error;
2544 return (inp);
2545 }
2546 #if 0
2547 wakeup( &so->so_timeo);
2548 sorwakeup(so);
2549 sowwakeup(so);
2550 #endif
2551 }
2552
2553 static int
tcp_pcblist(SYSCTL_HANDLER_ARGS)2554 tcp_pcblist(SYSCTL_HANDLER_ARGS)
2555 {
2556 struct inpcb_iterator inpi = INP_ALL_ITERATOR(&V_tcbinfo,
2557 INPLOOKUP_RLOCKPCB);
2558 struct xinpgen xig;
2559 struct inpcb *inp;
2560 int error;
2561
2562 if (req->newptr != NULL)
2563 return (EPERM);
2564
2565 if (req->oldptr == NULL) {
2566 int n;
2567
2568 n = V_tcbinfo.ipi_count +
2569 counter_u64_fetch(V_tcps_states[TCPS_SYN_RECEIVED]);
2570 n += imax(n / 8, 10);
2571 req->oldidx = 2 * (sizeof xig) + n * sizeof(struct xtcpcb);
2572 return (0);
2573 }
2574
2575 if ((error = sysctl_wire_old_buffer(req, 0)) != 0)
2576 return (error);
2577
2578 bzero(&xig, sizeof(xig));
2579 xig.xig_len = sizeof xig;
2580 xig.xig_count = V_tcbinfo.ipi_count +
2581 counter_u64_fetch(V_tcps_states[TCPS_SYN_RECEIVED]);
2582 xig.xig_gen = V_tcbinfo.ipi_gencnt;
2583 xig.xig_sogen = so_gencnt;
2584 error = SYSCTL_OUT(req, &xig, sizeof xig);
2585 if (error)
2586 return (error);
2587
2588 error = syncache_pcblist(req);
2589 if (error)
2590 return (error);
2591
2592 while ((inp = inp_next(&inpi)) != NULL) {
2593 if (inp->inp_gencnt <= xig.xig_gen &&
2594 cr_canseeinpcb(req->td->td_ucred, inp) == 0) {
2595 struct xtcpcb xt;
2596
2597 tcp_inptoxtp(inp, &xt);
2598 error = SYSCTL_OUT(req, &xt, sizeof xt);
2599 if (error) {
2600 INP_RUNLOCK(inp);
2601 break;
2602 } else
2603 continue;
2604 }
2605 }
2606
2607 if (!error) {
2608 /*
2609 * Give the user an updated idea of our state.
2610 * If the generation differs from what we told
2611 * her before, she knows that something happened
2612 * while we were processing this request, and it
2613 * might be necessary to retry.
2614 */
2615 xig.xig_gen = V_tcbinfo.ipi_gencnt;
2616 xig.xig_sogen = so_gencnt;
2617 xig.xig_count = V_tcbinfo.ipi_count +
2618 counter_u64_fetch(V_tcps_states[TCPS_SYN_RECEIVED]);
2619 error = SYSCTL_OUT(req, &xig, sizeof xig);
2620 }
2621
2622 return (error);
2623 }
2624
2625 SYSCTL_PROC(_net_inet_tcp, TCPCTL_PCBLIST, pcblist,
2626 CTLTYPE_OPAQUE | CTLFLAG_RD | CTLFLAG_NEEDGIANT,
2627 NULL, 0, tcp_pcblist, "S,xtcpcb",
2628 "List of active TCP connections");
2629
2630 #ifdef INET
2631 static int
tcp_getcred(SYSCTL_HANDLER_ARGS)2632 tcp_getcred(SYSCTL_HANDLER_ARGS)
2633 {
2634 struct xucred xuc;
2635 struct sockaddr_in addrs[2];
2636 struct epoch_tracker et;
2637 struct inpcb *inp;
2638 int error;
2639
2640 error = priv_check(req->td, PRIV_NETINET_GETCRED);
2641 if (error)
2642 return (error);
2643 error = SYSCTL_IN(req, addrs, sizeof(addrs));
2644 if (error)
2645 return (error);
2646 NET_EPOCH_ENTER(et);
2647 inp = in_pcblookup(&V_tcbinfo, addrs[1].sin_addr, addrs[1].sin_port,
2648 addrs[0].sin_addr, addrs[0].sin_port, INPLOOKUP_RLOCKPCB, NULL);
2649 NET_EPOCH_EXIT(et);
2650 if (inp != NULL) {
2651 if (error == 0)
2652 error = cr_canseeinpcb(req->td->td_ucred, inp);
2653 if (error == 0)
2654 cru2x(inp->inp_cred, &xuc);
2655 INP_RUNLOCK(inp);
2656 } else
2657 error = ENOENT;
2658 if (error == 0)
2659 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred));
2660 return (error);
2661 }
2662
2663 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, getcred,
2664 CTLTYPE_OPAQUE | CTLFLAG_RW | CTLFLAG_PRISON | CTLFLAG_NEEDGIANT,
2665 0, 0, tcp_getcred, "S,xucred",
2666 "Get the xucred of a TCP connection");
2667 #endif /* INET */
2668
2669 #ifdef INET6
2670 static int
tcp6_getcred(SYSCTL_HANDLER_ARGS)2671 tcp6_getcred(SYSCTL_HANDLER_ARGS)
2672 {
2673 struct epoch_tracker et;
2674 struct xucred xuc;
2675 struct sockaddr_in6 addrs[2];
2676 struct inpcb *inp;
2677 int error;
2678 #ifdef INET
2679 int mapped = 0;
2680 #endif
2681
2682 error = priv_check(req->td, PRIV_NETINET_GETCRED);
2683 if (error)
2684 return (error);
2685 error = SYSCTL_IN(req, addrs, sizeof(addrs));
2686 if (error)
2687 return (error);
2688 if ((error = sa6_embedscope(&addrs[0], V_ip6_use_defzone)) != 0 ||
2689 (error = sa6_embedscope(&addrs[1], V_ip6_use_defzone)) != 0) {
2690 return (error);
2691 }
2692 if (IN6_IS_ADDR_V4MAPPED(&addrs[0].sin6_addr)) {
2693 #ifdef INET
2694 if (IN6_IS_ADDR_V4MAPPED(&addrs[1].sin6_addr))
2695 mapped = 1;
2696 else
2697 #endif
2698 return (EINVAL);
2699 }
2700
2701 NET_EPOCH_ENTER(et);
2702 #ifdef INET
2703 if (mapped == 1)
2704 inp = in_pcblookup(&V_tcbinfo,
2705 *(struct in_addr *)&addrs[1].sin6_addr.s6_addr[12],
2706 addrs[1].sin6_port,
2707 *(struct in_addr *)&addrs[0].sin6_addr.s6_addr[12],
2708 addrs[0].sin6_port, INPLOOKUP_RLOCKPCB, NULL);
2709 else
2710 #endif
2711 inp = in6_pcblookup(&V_tcbinfo,
2712 &addrs[1].sin6_addr, addrs[1].sin6_port,
2713 &addrs[0].sin6_addr, addrs[0].sin6_port,
2714 INPLOOKUP_RLOCKPCB, NULL);
2715 NET_EPOCH_EXIT(et);
2716 if (inp != NULL) {
2717 if (error == 0)
2718 error = cr_canseeinpcb(req->td->td_ucred, inp);
2719 if (error == 0)
2720 cru2x(inp->inp_cred, &xuc);
2721 INP_RUNLOCK(inp);
2722 } else
2723 error = ENOENT;
2724 if (error == 0)
2725 error = SYSCTL_OUT(req, &xuc, sizeof(struct xucred));
2726 return (error);
2727 }
2728
2729 SYSCTL_PROC(_net_inet6_tcp6, OID_AUTO, getcred,
2730 CTLTYPE_OPAQUE | CTLFLAG_RW | CTLFLAG_PRISON | CTLFLAG_NEEDGIANT,
2731 0, 0, tcp6_getcred, "S,xucred",
2732 "Get the xucred of a TCP6 connection");
2733 #endif /* INET6 */
2734
2735 #ifdef INET
2736 /* Path MTU to try next when a fragmentation-needed message is received. */
2737 static inline int
tcp_next_pmtu(const struct icmp * icp,const struct ip * ip)2738 tcp_next_pmtu(const struct icmp *icp, const struct ip *ip)
2739 {
2740 int mtu = ntohs(icp->icmp_nextmtu);
2741
2742 /* If no alternative MTU was proposed, try the next smaller one. */
2743 if (!mtu)
2744 mtu = ip_next_mtu(ntohs(ip->ip_len), 1);
2745 if (mtu < V_tcp_minmss + sizeof(struct tcpiphdr))
2746 mtu = V_tcp_minmss + sizeof(struct tcpiphdr);
2747
2748 return (mtu);
2749 }
2750
2751 static void
tcp_ctlinput_with_port(struct icmp * icp,uint16_t port)2752 tcp_ctlinput_with_port(struct icmp *icp, uint16_t port)
2753 {
2754 struct ip *ip;
2755 struct tcphdr *th;
2756 struct inpcb *inp;
2757 struct tcpcb *tp;
2758 struct inpcb *(*notify)(struct inpcb *, int);
2759 struct in_conninfo inc;
2760 tcp_seq icmp_tcp_seq;
2761 int errno, mtu;
2762
2763 errno = icmp_errmap(icp);
2764 switch (errno) {
2765 case 0:
2766 return;
2767 case EMSGSIZE:
2768 notify = tcp_mtudisc_notify;
2769 break;
2770 case ECONNREFUSED:
2771 if (V_icmp_may_rst)
2772 notify = tcp_drop_syn_sent;
2773 else
2774 notify = tcp_notify;
2775 break;
2776 case EHOSTUNREACH:
2777 if (V_icmp_may_rst && icp->icmp_type == ICMP_TIMXCEED)
2778 notify = tcp_drop_syn_sent;
2779 else
2780 notify = tcp_notify;
2781 break;
2782 default:
2783 notify = tcp_notify;
2784 }
2785
2786 ip = &icp->icmp_ip;
2787 th = (struct tcphdr *)((caddr_t)ip + (ip->ip_hl << 2));
2788 icmp_tcp_seq = th->th_seq;
2789 inp = in_pcblookup(&V_tcbinfo, ip->ip_dst, th->th_dport, ip->ip_src,
2790 th->th_sport, INPLOOKUP_WLOCKPCB, NULL);
2791 if (inp != NULL) {
2792 tp = intotcpcb(inp);
2793 #ifdef TCP_OFFLOAD
2794 if (tp->t_flags & TF_TOE && errno == EMSGSIZE) {
2795 /*
2796 * MTU discovery for offloaded connections. Let
2797 * the TOE driver verify seq# and process it.
2798 */
2799 mtu = tcp_next_pmtu(icp, ip);
2800 tcp_offload_pmtu_update(tp, icmp_tcp_seq, mtu);
2801 goto out;
2802 }
2803 #endif
2804 if (tp->t_port != port)
2805 goto out;
2806 if (SEQ_GEQ(ntohl(icmp_tcp_seq), tp->snd_una) &&
2807 SEQ_LT(ntohl(icmp_tcp_seq), tp->snd_max)) {
2808 if (errno == EMSGSIZE) {
2809 /*
2810 * MTU discovery: we got a needfrag and
2811 * will potentially try a lower MTU.
2812 */
2813 mtu = tcp_next_pmtu(icp, ip);
2814
2815 /*
2816 * Only process the offered MTU if it
2817 * is smaller than the current one.
2818 */
2819 if (mtu < tp->t_maxseg +
2820 sizeof(struct tcpiphdr)) {
2821 bzero(&inc, sizeof(inc));
2822 inc.inc_faddr = ip->ip_dst;
2823 inc.inc_fibnum =
2824 inp->inp_inc.inc_fibnum;
2825 tcp_hc_updatemtu(&inc, mtu);
2826 inp = tcp_mtudisc(inp, mtu);
2827 }
2828 } else
2829 inp = (*notify)(inp, errno);
2830 }
2831 } else {
2832 bzero(&inc, sizeof(inc));
2833 inc.inc_fport = th->th_dport;
2834 inc.inc_lport = th->th_sport;
2835 inc.inc_faddr = ip->ip_dst;
2836 inc.inc_laddr = ip->ip_src;
2837 syncache_unreach(&inc, icmp_tcp_seq, port);
2838 }
2839 out:
2840 if (inp != NULL)
2841 INP_WUNLOCK(inp);
2842 }
2843
2844 static void
tcp_ctlinput(struct icmp * icmp)2845 tcp_ctlinput(struct icmp *icmp)
2846 {
2847 tcp_ctlinput_with_port(icmp, htons(0));
2848 }
2849
2850 static void
tcp_ctlinput_viaudp(udp_tun_icmp_param_t param)2851 tcp_ctlinput_viaudp(udp_tun_icmp_param_t param)
2852 {
2853 /* Its a tunneled TCP over UDP icmp */
2854 struct icmp *icmp = param.icmp;
2855 struct ip *outer_ip, *inner_ip;
2856 struct udphdr *udp;
2857 struct tcphdr *th, ttemp;
2858 int i_hlen, o_len;
2859 uint16_t port;
2860
2861 outer_ip = (struct ip *)((caddr_t)icmp - sizeof(struct ip));
2862 inner_ip = &icmp->icmp_ip;
2863 i_hlen = inner_ip->ip_hl << 2;
2864 o_len = ntohs(outer_ip->ip_len);
2865 if (o_len <
2866 (sizeof(struct ip) + 8 + i_hlen + sizeof(struct udphdr) + offsetof(struct tcphdr, th_ack))) {
2867 /* Not enough data present */
2868 return;
2869 }
2870 /* Ok lets strip out the inner udphdr header by copying up on top of it the tcp hdr */
2871 udp = (struct udphdr *)(((caddr_t)inner_ip) + i_hlen);
2872 if (ntohs(udp->uh_sport) != V_tcp_udp_tunneling_port) {
2873 return;
2874 }
2875 port = udp->uh_dport;
2876 th = (struct tcphdr *)(udp + 1);
2877 memcpy(&ttemp, th, sizeof(struct tcphdr));
2878 memcpy(udp, &ttemp, sizeof(struct tcphdr));
2879 /* Now adjust down the size of the outer IP header */
2880 o_len -= sizeof(struct udphdr);
2881 outer_ip->ip_len = htons(o_len);
2882 /* Now call in to the normal handling code */
2883 tcp_ctlinput_with_port(icmp, port);
2884 }
2885 #endif /* INET */
2886
2887 #ifdef INET6
2888 static inline int
tcp6_next_pmtu(const struct icmp6_hdr * icmp6)2889 tcp6_next_pmtu(const struct icmp6_hdr *icmp6)
2890 {
2891 int mtu = ntohl(icmp6->icmp6_mtu);
2892
2893 /*
2894 * If no alternative MTU was proposed, or the proposed MTU was too
2895 * small, set to the min.
2896 */
2897 if (mtu < IPV6_MMTU)
2898 mtu = IPV6_MMTU - 8; /* XXXNP: what is the adjustment for? */
2899 return (mtu);
2900 }
2901
2902 static void
tcp6_ctlinput_with_port(struct ip6ctlparam * ip6cp,uint16_t port)2903 tcp6_ctlinput_with_port(struct ip6ctlparam *ip6cp, uint16_t port)
2904 {
2905 struct in6_addr *dst;
2906 struct inpcb *(*notify)(struct inpcb *, int);
2907 struct ip6_hdr *ip6;
2908 struct mbuf *m;
2909 struct inpcb *inp;
2910 struct tcpcb *tp;
2911 struct icmp6_hdr *icmp6;
2912 struct in_conninfo inc;
2913 struct tcp_ports {
2914 uint16_t th_sport;
2915 uint16_t th_dport;
2916 } t_ports;
2917 tcp_seq icmp_tcp_seq;
2918 unsigned int mtu;
2919 unsigned int off;
2920 int errno;
2921
2922 icmp6 = ip6cp->ip6c_icmp6;
2923 m = ip6cp->ip6c_m;
2924 ip6 = ip6cp->ip6c_ip6;
2925 off = ip6cp->ip6c_off;
2926 dst = &ip6cp->ip6c_finaldst->sin6_addr;
2927
2928 errno = icmp6_errmap(icmp6);
2929 switch (errno) {
2930 case 0:
2931 return;
2932 case EMSGSIZE:
2933 notify = tcp_mtudisc_notify;
2934 break;
2935 case ECONNREFUSED:
2936 if (V_icmp_may_rst)
2937 notify = tcp_drop_syn_sent;
2938 else
2939 notify = tcp_notify;
2940 break;
2941 case EHOSTUNREACH:
2942 /*
2943 * There are only four ICMPs that may reset connection:
2944 * - administratively prohibited
2945 * - port unreachable
2946 * - time exceeded in transit
2947 * - unknown next header
2948 */
2949 if (V_icmp_may_rst &&
2950 ((icmp6->icmp6_type == ICMP6_DST_UNREACH &&
2951 (icmp6->icmp6_code == ICMP6_DST_UNREACH_ADMIN ||
2952 icmp6->icmp6_code == ICMP6_DST_UNREACH_NOPORT)) ||
2953 (icmp6->icmp6_type == ICMP6_TIME_EXCEEDED &&
2954 icmp6->icmp6_code == ICMP6_TIME_EXCEED_TRANSIT) ||
2955 (icmp6->icmp6_type == ICMP6_PARAM_PROB &&
2956 icmp6->icmp6_code == ICMP6_PARAMPROB_NEXTHEADER)))
2957 notify = tcp_drop_syn_sent;
2958 else
2959 notify = tcp_notify;
2960 break;
2961 default:
2962 notify = tcp_notify;
2963 }
2964
2965 /* Check if we can safely get the ports from the tcp hdr */
2966 if (m == NULL ||
2967 (m->m_pkthdr.len <
2968 (int32_t) (off + sizeof(struct tcp_ports)))) {
2969 return;
2970 }
2971 bzero(&t_ports, sizeof(struct tcp_ports));
2972 m_copydata(m, off, sizeof(struct tcp_ports), (caddr_t)&t_ports);
2973 inp = in6_pcblookup(&V_tcbinfo, &ip6->ip6_dst, t_ports.th_dport,
2974 &ip6->ip6_src, t_ports.th_sport, INPLOOKUP_WLOCKPCB, NULL);
2975 off += sizeof(struct tcp_ports);
2976 if (m->m_pkthdr.len < (int32_t) (off + sizeof(tcp_seq))) {
2977 goto out;
2978 }
2979 m_copydata(m, off, sizeof(tcp_seq), (caddr_t)&icmp_tcp_seq);
2980 if (inp != NULL) {
2981 tp = intotcpcb(inp);
2982 #ifdef TCP_OFFLOAD
2983 if (tp->t_flags & TF_TOE && errno == EMSGSIZE) {
2984 /* MTU discovery for offloaded connections. */
2985 mtu = tcp6_next_pmtu(icmp6);
2986 tcp_offload_pmtu_update(tp, icmp_tcp_seq, mtu);
2987 goto out;
2988 }
2989 #endif
2990 if (tp->t_port != port)
2991 goto out;
2992 if (SEQ_GEQ(ntohl(icmp_tcp_seq), tp->snd_una) &&
2993 SEQ_LT(ntohl(icmp_tcp_seq), tp->snd_max)) {
2994 if (errno == EMSGSIZE) {
2995 /*
2996 * MTU discovery:
2997 * If we got a needfrag set the MTU
2998 * in the route to the suggested new
2999 * value (if given) and then notify.
3000 */
3001 mtu = tcp6_next_pmtu(icmp6);
3002
3003 bzero(&inc, sizeof(inc));
3004 inc.inc_fibnum = M_GETFIB(m);
3005 inc.inc_flags |= INC_ISIPV6;
3006 inc.inc6_faddr = *dst;
3007 if (in6_setscope(&inc.inc6_faddr,
3008 m->m_pkthdr.rcvif, NULL))
3009 goto out;
3010 /*
3011 * Only process the offered MTU if it
3012 * is smaller than the current one.
3013 */
3014 if (mtu < tp->t_maxseg +
3015 sizeof (struct tcphdr) +
3016 sizeof (struct ip6_hdr)) {
3017 tcp_hc_updatemtu(&inc, mtu);
3018 tcp_mtudisc(inp, mtu);
3019 ICMP6STAT_INC(icp6s_pmtuchg);
3020 }
3021 } else
3022 inp = (*notify)(inp, errno);
3023 }
3024 } else {
3025 bzero(&inc, sizeof(inc));
3026 inc.inc_fibnum = M_GETFIB(m);
3027 inc.inc_flags |= INC_ISIPV6;
3028 inc.inc_fport = t_ports.th_dport;
3029 inc.inc_lport = t_ports.th_sport;
3030 inc.inc6_faddr = *dst;
3031 inc.inc6_laddr = ip6->ip6_src;
3032 syncache_unreach(&inc, icmp_tcp_seq, port);
3033 }
3034 out:
3035 if (inp != NULL)
3036 INP_WUNLOCK(inp);
3037 }
3038
3039 static void
tcp6_ctlinput(struct ip6ctlparam * ctl)3040 tcp6_ctlinput(struct ip6ctlparam *ctl)
3041 {
3042 tcp6_ctlinput_with_port(ctl, htons(0));
3043 }
3044
3045 static void
tcp6_ctlinput_viaudp(udp_tun_icmp_param_t param)3046 tcp6_ctlinput_viaudp(udp_tun_icmp_param_t param)
3047 {
3048 struct ip6ctlparam *ip6cp = param.ip6cp;
3049 struct mbuf *m;
3050 struct udphdr *udp;
3051 uint16_t port;
3052
3053 m = m_pulldown(ip6cp->ip6c_m, ip6cp->ip6c_off, sizeof(struct udphdr), NULL);
3054 if (m == NULL) {
3055 return;
3056 }
3057 udp = mtod(m, struct udphdr *);
3058 if (ntohs(udp->uh_sport) != V_tcp_udp_tunneling_port) {
3059 return;
3060 }
3061 port = udp->uh_dport;
3062 m_adj(m, sizeof(struct udphdr));
3063 if ((m->m_flags & M_PKTHDR) == 0) {
3064 ip6cp->ip6c_m->m_pkthdr.len -= sizeof(struct udphdr);
3065 }
3066 /* Now call in to the normal handling code */
3067 tcp6_ctlinput_with_port(ip6cp, port);
3068 }
3069
3070 #endif /* INET6 */
3071
3072 static uint32_t
tcp_keyed_hash(struct in_conninfo * inc,u_char * key,u_int len)3073 tcp_keyed_hash(struct in_conninfo *inc, u_char *key, u_int len)
3074 {
3075 SIPHASH_CTX ctx;
3076 uint32_t hash[2];
3077
3078 KASSERT(len >= SIPHASH_KEY_LENGTH,
3079 ("%s: keylen %u too short ", __func__, len));
3080 SipHash24_Init(&ctx);
3081 SipHash_SetKey(&ctx, (uint8_t *)key);
3082 SipHash_Update(&ctx, &inc->inc_fport, sizeof(uint16_t));
3083 SipHash_Update(&ctx, &inc->inc_lport, sizeof(uint16_t));
3084 switch (inc->inc_flags & INC_ISIPV6) {
3085 #ifdef INET
3086 case 0:
3087 SipHash_Update(&ctx, &inc->inc_faddr, sizeof(struct in_addr));
3088 SipHash_Update(&ctx, &inc->inc_laddr, sizeof(struct in_addr));
3089 break;
3090 #endif
3091 #ifdef INET6
3092 case INC_ISIPV6:
3093 SipHash_Update(&ctx, &inc->inc6_faddr, sizeof(struct in6_addr));
3094 SipHash_Update(&ctx, &inc->inc6_laddr, sizeof(struct in6_addr));
3095 break;
3096 #endif
3097 }
3098 SipHash_Final((uint8_t *)hash, &ctx);
3099
3100 return (hash[0] ^ hash[1]);
3101 }
3102
3103 uint32_t
tcp_new_ts_offset(struct in_conninfo * inc)3104 tcp_new_ts_offset(struct in_conninfo *inc)
3105 {
3106 struct in_conninfo inc_store, *local_inc;
3107
3108 if (!V_tcp_ts_offset_per_conn) {
3109 memcpy(&inc_store, inc, sizeof(struct in_conninfo));
3110 inc_store.inc_lport = 0;
3111 inc_store.inc_fport = 0;
3112 local_inc = &inc_store;
3113 } else {
3114 local_inc = inc;
3115 }
3116 return (tcp_keyed_hash(local_inc, V_ts_offset_secret,
3117 sizeof(V_ts_offset_secret)));
3118 }
3119
3120 /*
3121 * Following is where TCP initial sequence number generation occurs.
3122 *
3123 * There are two places where we must use initial sequence numbers:
3124 * 1. In SYN-ACK packets.
3125 * 2. In SYN packets.
3126 *
3127 * All ISNs for SYN-ACK packets are generated by the syncache. See
3128 * tcp_syncache.c for details.
3129 *
3130 * The ISNs in SYN packets must be monotonic; TIME_WAIT recycling
3131 * depends on this property. In addition, these ISNs should be
3132 * unguessable so as to prevent connection hijacking. To satisfy
3133 * the requirements of this situation, the algorithm outlined in
3134 * RFC 1948 is used, with only small modifications.
3135 *
3136 * Implementation details:
3137 *
3138 * Time is based off the system timer, and is corrected so that it
3139 * increases by one megabyte per second. This allows for proper
3140 * recycling on high speed LANs while still leaving over an hour
3141 * before rollover.
3142 *
3143 * As reading the *exact* system time is too expensive to be done
3144 * whenever setting up a TCP connection, we increment the time
3145 * offset in two ways. First, a small random positive increment
3146 * is added to isn_offset for each connection that is set up.
3147 * Second, the function tcp_isn_tick fires once per clock tick
3148 * and increments isn_offset as necessary so that sequence numbers
3149 * are incremented at approximately ISN_BYTES_PER_SECOND. The
3150 * random positive increments serve only to ensure that the same
3151 * exact sequence number is never sent out twice (as could otherwise
3152 * happen when a port is recycled in less than the system tick
3153 * interval.)
3154 *
3155 * net.inet.tcp.isn_reseed_interval controls the number of seconds
3156 * between seeding of isn_secret. This is normally set to zero,
3157 * as reseeding should not be necessary.
3158 *
3159 * Locking of the global variables isn_secret, isn_last_reseed, isn_offset,
3160 * isn_offset_old, and isn_ctx is performed using the ISN lock. In
3161 * general, this means holding an exclusive (write) lock.
3162 */
3163
3164 #define ISN_BYTES_PER_SECOND 1048576
3165 #define ISN_STATIC_INCREMENT 4096
3166 #define ISN_RANDOM_INCREMENT (4096 - 1)
3167 #define ISN_SECRET_LENGTH SIPHASH_KEY_LENGTH
3168
3169 VNET_DEFINE_STATIC(u_char, isn_secret[ISN_SECRET_LENGTH]);
3170 VNET_DEFINE_STATIC(int, isn_last);
3171 VNET_DEFINE_STATIC(int, isn_last_reseed);
3172 VNET_DEFINE_STATIC(u_int32_t, isn_offset);
3173 VNET_DEFINE_STATIC(u_int32_t, isn_offset_old);
3174
3175 #define V_isn_secret VNET(isn_secret)
3176 #define V_isn_last VNET(isn_last)
3177 #define V_isn_last_reseed VNET(isn_last_reseed)
3178 #define V_isn_offset VNET(isn_offset)
3179 #define V_isn_offset_old VNET(isn_offset_old)
3180
3181 tcp_seq
tcp_new_isn(struct in_conninfo * inc)3182 tcp_new_isn(struct in_conninfo *inc)
3183 {
3184 tcp_seq new_isn;
3185 u_int32_t projected_offset;
3186
3187 ISN_LOCK();
3188 /* Seed if this is the first use, reseed if requested. */
3189 if ((V_isn_last_reseed == 0) || ((V_tcp_isn_reseed_interval > 0) &&
3190 (((u_int)V_isn_last_reseed + (u_int)V_tcp_isn_reseed_interval*hz)
3191 < (u_int)ticks))) {
3192 arc4rand(&V_isn_secret, sizeof(V_isn_secret), 0);
3193 V_isn_last_reseed = ticks;
3194 }
3195
3196 /* Compute the hash and return the ISN. */
3197 new_isn = (tcp_seq)tcp_keyed_hash(inc, V_isn_secret,
3198 sizeof(V_isn_secret));
3199 V_isn_offset += ISN_STATIC_INCREMENT +
3200 (arc4random() & ISN_RANDOM_INCREMENT);
3201 if (ticks != V_isn_last) {
3202 projected_offset = V_isn_offset_old +
3203 ISN_BYTES_PER_SECOND / hz * (ticks - V_isn_last);
3204 if (SEQ_GT(projected_offset, V_isn_offset))
3205 V_isn_offset = projected_offset;
3206 V_isn_offset_old = V_isn_offset;
3207 V_isn_last = ticks;
3208 }
3209 new_isn += V_isn_offset;
3210 ISN_UNLOCK();
3211 return (new_isn);
3212 }
3213
3214 /*
3215 * When a specific ICMP unreachable message is received and the
3216 * connection state is SYN-SENT, drop the connection. This behavior
3217 * is controlled by the icmp_may_rst sysctl.
3218 */
3219 static struct inpcb *
tcp_drop_syn_sent(struct inpcb * inp,int errno)3220 tcp_drop_syn_sent(struct inpcb *inp, int errno)
3221 {
3222 struct tcpcb *tp;
3223
3224 NET_EPOCH_ASSERT();
3225 INP_WLOCK_ASSERT(inp);
3226
3227 tp = intotcpcb(inp);
3228 if (tp->t_state != TCPS_SYN_SENT)
3229 return (inp);
3230
3231 if (tp->t_flags & TF_FASTOPEN)
3232 tcp_fastopen_disable_path(tp);
3233
3234 tp = tcp_drop(tp, errno);
3235 if (tp != NULL)
3236 return (inp);
3237 else
3238 return (NULL);
3239 }
3240
3241 /*
3242 * When `need fragmentation' ICMP is received, update our idea of the MSS
3243 * based on the new value. Also nudge TCP to send something, since we
3244 * know the packet we just sent was dropped.
3245 * This duplicates some code in the tcp_mss() function in tcp_input.c.
3246 */
3247 static struct inpcb *
tcp_mtudisc_notify(struct inpcb * inp,int error)3248 tcp_mtudisc_notify(struct inpcb *inp, int error)
3249 {
3250
3251 return (tcp_mtudisc(inp, -1));
3252 }
3253
3254 static struct inpcb *
tcp_mtudisc(struct inpcb * inp,int mtuoffer)3255 tcp_mtudisc(struct inpcb *inp, int mtuoffer)
3256 {
3257 struct tcpcb *tp;
3258 struct socket *so;
3259
3260 INP_WLOCK_ASSERT(inp);
3261
3262 tp = intotcpcb(inp);
3263 KASSERT(tp != NULL, ("tcp_mtudisc: tp == NULL"));
3264
3265 tcp_mss_update(tp, -1, mtuoffer, NULL, NULL);
3266
3267 so = inp->inp_socket;
3268 SOCKBUF_LOCK(&so->so_snd);
3269 /* If the mss is larger than the socket buffer, decrease the mss. */
3270 if (so->so_snd.sb_hiwat < tp->t_maxseg) {
3271 tp->t_maxseg = so->so_snd.sb_hiwat;
3272 if (tp->t_maxseg < V_tcp_mssdflt) {
3273 /*
3274 * The MSS is so small we should not process incoming
3275 * SACK's since we are subject to attack in such a
3276 * case.
3277 */
3278 tp->t_flags2 |= TF2_PROC_SACK_PROHIBIT;
3279 } else {
3280 tp->t_flags2 &= ~TF2_PROC_SACK_PROHIBIT;
3281 }
3282 }
3283 SOCKBUF_UNLOCK(&so->so_snd);
3284
3285 TCPSTAT_INC(tcps_mturesent);
3286 tp->t_rtttime = 0;
3287 tp->snd_nxt = tp->snd_una;
3288 tcp_free_sackholes(tp);
3289 tp->snd_recover = tp->snd_max;
3290 if (tp->t_flags & TF_SACK_PERMIT)
3291 EXIT_FASTRECOVERY(tp->t_flags);
3292 if (tp->t_fb->tfb_tcp_mtu_chg != NULL) {
3293 /*
3294 * Conceptually the snd_nxt setting
3295 * and freeing sack holes should
3296 * be done by the default stacks
3297 * own tfb_tcp_mtu_chg().
3298 */
3299 tp->t_fb->tfb_tcp_mtu_chg(tp);
3300 }
3301 if (tcp_output(tp) < 0)
3302 return (NULL);
3303 else
3304 return (inp);
3305 }
3306
3307 #ifdef INET
3308 /*
3309 * Look-up the routing entry to the peer of this inpcb. If no route
3310 * is found and it cannot be allocated, then return 0. This routine
3311 * is called by TCP routines that access the rmx structure and by
3312 * tcp_mss_update to get the peer/interface MTU.
3313 */
3314 uint32_t
tcp_maxmtu(struct in_conninfo * inc,struct tcp_ifcap * cap)3315 tcp_maxmtu(struct in_conninfo *inc, struct tcp_ifcap *cap)
3316 {
3317 struct nhop_object *nh;
3318 struct ifnet *ifp;
3319 uint32_t maxmtu = 0;
3320
3321 KASSERT(inc != NULL, ("tcp_maxmtu with NULL in_conninfo pointer"));
3322
3323 if (inc->inc_faddr.s_addr != INADDR_ANY) {
3324 nh = fib4_lookup(inc->inc_fibnum, inc->inc_faddr, 0, NHR_NONE, 0);
3325 if (nh == NULL)
3326 return (0);
3327
3328 ifp = nh->nh_ifp;
3329 maxmtu = nh->nh_mtu;
3330
3331 /* Report additional interface capabilities. */
3332 if (cap != NULL) {
3333 if (ifp->if_capenable & IFCAP_TSO4 &&
3334 ifp->if_hwassist & CSUM_TSO) {
3335 cap->ifcap |= CSUM_TSO;
3336 cap->tsomax = ifp->if_hw_tsomax;
3337 cap->tsomaxsegcount = ifp->if_hw_tsomaxsegcount;
3338 cap->tsomaxsegsize = ifp->if_hw_tsomaxsegsize;
3339 }
3340 }
3341 }
3342 return (maxmtu);
3343 }
3344 #endif /* INET */
3345
3346 #ifdef INET6
3347 uint32_t
tcp_maxmtu6(struct in_conninfo * inc,struct tcp_ifcap * cap)3348 tcp_maxmtu6(struct in_conninfo *inc, struct tcp_ifcap *cap)
3349 {
3350 struct nhop_object *nh;
3351 struct in6_addr dst6;
3352 uint32_t scopeid;
3353 struct ifnet *ifp;
3354 uint32_t maxmtu = 0;
3355
3356 KASSERT(inc != NULL, ("tcp_maxmtu6 with NULL in_conninfo pointer"));
3357
3358 if (inc->inc_flags & INC_IPV6MINMTU)
3359 return (IPV6_MMTU);
3360
3361 if (!IN6_IS_ADDR_UNSPECIFIED(&inc->inc6_faddr)) {
3362 in6_splitscope(&inc->inc6_faddr, &dst6, &scopeid);
3363 nh = fib6_lookup(inc->inc_fibnum, &dst6, scopeid, NHR_NONE, 0);
3364 if (nh == NULL)
3365 return (0);
3366
3367 ifp = nh->nh_ifp;
3368 maxmtu = nh->nh_mtu;
3369
3370 /* Report additional interface capabilities. */
3371 if (cap != NULL) {
3372 if (ifp->if_capenable & IFCAP_TSO6 &&
3373 ifp->if_hwassist & CSUM_TSO) {
3374 cap->ifcap |= CSUM_TSO;
3375 cap->tsomax = ifp->if_hw_tsomax;
3376 cap->tsomaxsegcount = ifp->if_hw_tsomaxsegcount;
3377 cap->tsomaxsegsize = ifp->if_hw_tsomaxsegsize;
3378 }
3379 }
3380 }
3381
3382 return (maxmtu);
3383 }
3384
3385 /*
3386 * Handle setsockopt(IPV6_USE_MIN_MTU) by a TCP stack.
3387 *
3388 * XXXGL: we are updating inpcb here with INC_IPV6MINMTU flag.
3389 * The right place to do that is ip6_setpktopt() that has just been
3390 * executed. By the way it just filled ip6po_minmtu for us.
3391 */
3392 void
tcp6_use_min_mtu(struct tcpcb * tp)3393 tcp6_use_min_mtu(struct tcpcb *tp)
3394 {
3395 struct inpcb *inp = tptoinpcb(tp);
3396
3397 INP_WLOCK_ASSERT(inp);
3398 /*
3399 * In case of the IPV6_USE_MIN_MTU socket
3400 * option, the INC_IPV6MINMTU flag to announce
3401 * a corresponding MSS during the initial
3402 * handshake. If the TCP connection is not in
3403 * the front states, just reduce the MSS being
3404 * used. This avoids the sending of TCP
3405 * segments which will be fragmented at the
3406 * IPv6 layer.
3407 */
3408 inp->inp_inc.inc_flags |= INC_IPV6MINMTU;
3409 if ((tp->t_state >= TCPS_SYN_SENT) &&
3410 (inp->inp_inc.inc_flags & INC_ISIPV6)) {
3411 struct ip6_pktopts *opt;
3412
3413 opt = inp->in6p_outputopts;
3414 if (opt != NULL && opt->ip6po_minmtu == IP6PO_MINMTU_ALL &&
3415 tp->t_maxseg > TCP6_MSS) {
3416 tp->t_maxseg = TCP6_MSS;
3417 if (tp->t_maxseg < V_tcp_mssdflt) {
3418 /*
3419 * The MSS is so small we should not process incoming
3420 * SACK's since we are subject to attack in such a
3421 * case.
3422 */
3423 tp->t_flags2 |= TF2_PROC_SACK_PROHIBIT;
3424 } else {
3425 tp->t_flags2 &= ~TF2_PROC_SACK_PROHIBIT;
3426 }
3427 }
3428 }
3429 }
3430 #endif /* INET6 */
3431
3432 /*
3433 * Calculate effective SMSS per RFC5681 definition for a given TCP
3434 * connection at its current state, taking into account SACK and etc.
3435 */
3436 u_int
tcp_maxseg(const struct tcpcb * tp)3437 tcp_maxseg(const struct tcpcb *tp)
3438 {
3439 u_int optlen;
3440
3441 if (tp->t_flags & TF_NOOPT)
3442 return (tp->t_maxseg);
3443
3444 /*
3445 * Here we have a simplified code from tcp_addoptions(),
3446 * without a proper loop, and having most of paddings hardcoded.
3447 * We might make mistakes with padding here in some edge cases,
3448 * but this is harmless, since result of tcp_maxseg() is used
3449 * only in cwnd and ssthresh estimations.
3450 */
3451 if (TCPS_HAVEESTABLISHED(tp->t_state)) {
3452 if (tp->t_flags & TF_RCVD_TSTMP)
3453 optlen = TCPOLEN_TSTAMP_APPA;
3454 else
3455 optlen = 0;
3456 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE)
3457 if (tp->t_flags & TF_SIGNATURE)
3458 optlen += PADTCPOLEN(TCPOLEN_SIGNATURE);
3459 #endif
3460 if ((tp->t_flags & TF_SACK_PERMIT) && tp->rcv_numsacks > 0) {
3461 optlen += TCPOLEN_SACKHDR;
3462 optlen += tp->rcv_numsacks * TCPOLEN_SACK;
3463 optlen = PADTCPOLEN(optlen);
3464 }
3465 } else {
3466 if (tp->t_flags & TF_REQ_TSTMP)
3467 optlen = TCPOLEN_TSTAMP_APPA;
3468 else
3469 optlen = PADTCPOLEN(TCPOLEN_MAXSEG);
3470 if (tp->t_flags & TF_REQ_SCALE)
3471 optlen += PADTCPOLEN(TCPOLEN_WINDOW);
3472 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE)
3473 if (tp->t_flags & TF_SIGNATURE)
3474 optlen += PADTCPOLEN(TCPOLEN_SIGNATURE);
3475 #endif
3476 if (tp->t_flags & TF_SACK_PERMIT)
3477 optlen += PADTCPOLEN(TCPOLEN_SACK_PERMITTED);
3478 }
3479 optlen = min(optlen, TCP_MAXOLEN);
3480 return (tp->t_maxseg - optlen);
3481 }
3482
3483
3484 u_int
tcp_fixed_maxseg(const struct tcpcb * tp)3485 tcp_fixed_maxseg(const struct tcpcb *tp)
3486 {
3487 int optlen;
3488
3489 if (tp->t_flags & TF_NOOPT)
3490 return (tp->t_maxseg);
3491
3492 /*
3493 * Here we have a simplified code from tcp_addoptions(),
3494 * without a proper loop, and having most of paddings hardcoded.
3495 * We only consider fixed options that we would send every
3496 * time I.e. SACK is not considered. This is important
3497 * for cc modules to figure out what the modulo of the
3498 * cwnd should be.
3499 */
3500 if (TCPS_HAVEESTABLISHED(tp->t_state)) {
3501 if (tp->t_flags & TF_RCVD_TSTMP)
3502 optlen = TCPOLEN_TSTAMP_APPA;
3503 else
3504 optlen = 0;
3505 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE)
3506 if (tp->t_flags & TF_SIGNATURE)
3507 optlen += PADTCPOLEN(TCPOLEN_SIGNATURE);
3508 #endif
3509 } else {
3510 if (tp->t_flags & TF_REQ_TSTMP)
3511 optlen = TCPOLEN_TSTAMP_APPA;
3512 else
3513 optlen = PADTCPOLEN(TCPOLEN_MAXSEG);
3514 if (tp->t_flags & TF_REQ_SCALE)
3515 optlen += PADTCPOLEN(TCPOLEN_WINDOW);
3516 #if defined(IPSEC_SUPPORT) || defined(TCP_SIGNATURE)
3517 if (tp->t_flags & TF_SIGNATURE)
3518 optlen += PADTCPOLEN(TCPOLEN_SIGNATURE);
3519 #endif
3520 if (tp->t_flags & TF_SACK_PERMIT)
3521 optlen += PADTCPOLEN(TCPOLEN_SACK_PERMITTED);
3522 }
3523 optlen = min(optlen, TCP_MAXOLEN);
3524 return (tp->t_maxseg - optlen);
3525 }
3526
3527
3528
3529 static int
sysctl_drop(SYSCTL_HANDLER_ARGS)3530 sysctl_drop(SYSCTL_HANDLER_ARGS)
3531 {
3532 /* addrs[0] is a foreign socket, addrs[1] is a local one. */
3533 struct sockaddr_storage addrs[2];
3534 struct inpcb *inp;
3535 struct tcpcb *tp;
3536 #ifdef INET
3537 struct sockaddr_in *fin = NULL, *lin = NULL;
3538 #endif
3539 struct epoch_tracker et;
3540 #ifdef INET6
3541 struct sockaddr_in6 *fin6, *lin6;
3542 #endif
3543 int error;
3544
3545 inp = NULL;
3546 #ifdef INET6
3547 fin6 = lin6 = NULL;
3548 #endif
3549 error = 0;
3550
3551 if (req->oldptr != NULL || req->oldlen != 0)
3552 return (EINVAL);
3553 if (req->newptr == NULL)
3554 return (EPERM);
3555 if (req->newlen < sizeof(addrs))
3556 return (ENOMEM);
3557 error = SYSCTL_IN(req, &addrs, sizeof(addrs));
3558 if (error)
3559 return (error);
3560
3561 switch (addrs[0].ss_family) {
3562 #ifdef INET6
3563 case AF_INET6:
3564 fin6 = (struct sockaddr_in6 *)&addrs[0];
3565 lin6 = (struct sockaddr_in6 *)&addrs[1];
3566 if (fin6->sin6_len != sizeof(struct sockaddr_in6) ||
3567 lin6->sin6_len != sizeof(struct sockaddr_in6))
3568 return (EINVAL);
3569 if (IN6_IS_ADDR_V4MAPPED(&fin6->sin6_addr)) {
3570 if (!IN6_IS_ADDR_V4MAPPED(&lin6->sin6_addr))
3571 return (EINVAL);
3572 in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[0]);
3573 in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[1]);
3574 #ifdef INET
3575 fin = (struct sockaddr_in *)&addrs[0];
3576 lin = (struct sockaddr_in *)&addrs[1];
3577 #endif
3578 break;
3579 }
3580 error = sa6_embedscope(fin6, V_ip6_use_defzone);
3581 if (error)
3582 return (error);
3583 error = sa6_embedscope(lin6, V_ip6_use_defzone);
3584 if (error)
3585 return (error);
3586 break;
3587 #endif
3588 #ifdef INET
3589 case AF_INET:
3590 fin = (struct sockaddr_in *)&addrs[0];
3591 lin = (struct sockaddr_in *)&addrs[1];
3592 if (fin->sin_len != sizeof(struct sockaddr_in) ||
3593 lin->sin_len != sizeof(struct sockaddr_in))
3594 return (EINVAL);
3595 break;
3596 #endif
3597 default:
3598 return (EINVAL);
3599 }
3600 NET_EPOCH_ENTER(et);
3601 switch (addrs[0].ss_family) {
3602 #ifdef INET6
3603 case AF_INET6:
3604 inp = in6_pcblookup(&V_tcbinfo, &fin6->sin6_addr,
3605 fin6->sin6_port, &lin6->sin6_addr, lin6->sin6_port,
3606 INPLOOKUP_WLOCKPCB, NULL);
3607 break;
3608 #endif
3609 #ifdef INET
3610 case AF_INET:
3611 inp = in_pcblookup(&V_tcbinfo, fin->sin_addr, fin->sin_port,
3612 lin->sin_addr, lin->sin_port, INPLOOKUP_WLOCKPCB, NULL);
3613 break;
3614 #endif
3615 }
3616 if (inp != NULL) {
3617 if (!SOLISTENING(inp->inp_socket)) {
3618 tp = intotcpcb(inp);
3619 tp = tcp_drop(tp, ECONNABORTED);
3620 if (tp != NULL)
3621 INP_WUNLOCK(inp);
3622 } else
3623 INP_WUNLOCK(inp);
3624 } else
3625 error = ESRCH;
3626 NET_EPOCH_EXIT(et);
3627 return (error);
3628 }
3629
3630 SYSCTL_PROC(_net_inet_tcp, TCPCTL_DROP, drop,
3631 CTLFLAG_VNET | CTLTYPE_STRUCT | CTLFLAG_WR | CTLFLAG_SKIP |
3632 CTLFLAG_NEEDGIANT, NULL, 0, sysctl_drop, "",
3633 "Drop TCP connection");
3634
3635 static int
tcp_sysctl_setsockopt(SYSCTL_HANDLER_ARGS)3636 tcp_sysctl_setsockopt(SYSCTL_HANDLER_ARGS)
3637 {
3638 return (sysctl_setsockopt(oidp, arg1, arg2, req, &V_tcbinfo,
3639 &tcp_ctloutput_set));
3640 }
3641
3642 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, setsockopt,
3643 CTLFLAG_VNET | CTLTYPE_STRUCT | CTLFLAG_WR | CTLFLAG_SKIP |
3644 CTLFLAG_MPSAFE, NULL, 0, tcp_sysctl_setsockopt, "",
3645 "Set socket option for TCP endpoint");
3646
3647 #ifdef KERN_TLS
3648 static int
sysctl_switch_tls(SYSCTL_HANDLER_ARGS)3649 sysctl_switch_tls(SYSCTL_HANDLER_ARGS)
3650 {
3651 /* addrs[0] is a foreign socket, addrs[1] is a local one. */
3652 struct sockaddr_storage addrs[2];
3653 struct inpcb *inp;
3654 #ifdef INET
3655 struct sockaddr_in *fin = NULL, *lin = NULL;
3656 #endif
3657 struct epoch_tracker et;
3658 #ifdef INET6
3659 struct sockaddr_in6 *fin6, *lin6;
3660 #endif
3661 int error;
3662
3663 inp = NULL;
3664 #ifdef INET6
3665 fin6 = lin6 = NULL;
3666 #endif
3667 error = 0;
3668
3669 if (req->oldptr != NULL || req->oldlen != 0)
3670 return (EINVAL);
3671 if (req->newptr == NULL)
3672 return (EPERM);
3673 if (req->newlen < sizeof(addrs))
3674 return (ENOMEM);
3675 error = SYSCTL_IN(req, &addrs, sizeof(addrs));
3676 if (error)
3677 return (error);
3678
3679 switch (addrs[0].ss_family) {
3680 #ifdef INET6
3681 case AF_INET6:
3682 fin6 = (struct sockaddr_in6 *)&addrs[0];
3683 lin6 = (struct sockaddr_in6 *)&addrs[1];
3684 if (fin6->sin6_len != sizeof(struct sockaddr_in6) ||
3685 lin6->sin6_len != sizeof(struct sockaddr_in6))
3686 return (EINVAL);
3687 if (IN6_IS_ADDR_V4MAPPED(&fin6->sin6_addr)) {
3688 if (!IN6_IS_ADDR_V4MAPPED(&lin6->sin6_addr))
3689 return (EINVAL);
3690 in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[0]);
3691 in6_sin6_2_sin_in_sock((struct sockaddr *)&addrs[1]);
3692 #ifdef INET
3693 fin = (struct sockaddr_in *)&addrs[0];
3694 lin = (struct sockaddr_in *)&addrs[1];
3695 #endif
3696 break;
3697 }
3698 error = sa6_embedscope(fin6, V_ip6_use_defzone);
3699 if (error)
3700 return (error);
3701 error = sa6_embedscope(lin6, V_ip6_use_defzone);
3702 if (error)
3703 return (error);
3704 break;
3705 #endif
3706 #ifdef INET
3707 case AF_INET:
3708 fin = (struct sockaddr_in *)&addrs[0];
3709 lin = (struct sockaddr_in *)&addrs[1];
3710 if (fin->sin_len != sizeof(struct sockaddr_in) ||
3711 lin->sin_len != sizeof(struct sockaddr_in))
3712 return (EINVAL);
3713 break;
3714 #endif
3715 default:
3716 return (EINVAL);
3717 }
3718 NET_EPOCH_ENTER(et);
3719 switch (addrs[0].ss_family) {
3720 #ifdef INET6
3721 case AF_INET6:
3722 inp = in6_pcblookup(&V_tcbinfo, &fin6->sin6_addr,
3723 fin6->sin6_port, &lin6->sin6_addr, lin6->sin6_port,
3724 INPLOOKUP_WLOCKPCB, NULL);
3725 break;
3726 #endif
3727 #ifdef INET
3728 case AF_INET:
3729 inp = in_pcblookup(&V_tcbinfo, fin->sin_addr, fin->sin_port,
3730 lin->sin_addr, lin->sin_port, INPLOOKUP_WLOCKPCB, NULL);
3731 break;
3732 #endif
3733 }
3734 NET_EPOCH_EXIT(et);
3735 if (inp != NULL) {
3736 struct socket *so;
3737
3738 so = inp->inp_socket;
3739 soref(so);
3740 error = ktls_set_tx_mode(so,
3741 arg2 == 0 ? TCP_TLS_MODE_SW : TCP_TLS_MODE_IFNET);
3742 INP_WUNLOCK(inp);
3743 sorele(so);
3744 } else
3745 error = ESRCH;
3746 return (error);
3747 }
3748
3749 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, switch_to_sw_tls,
3750 CTLFLAG_VNET | CTLTYPE_STRUCT | CTLFLAG_WR | CTLFLAG_SKIP |
3751 CTLFLAG_NEEDGIANT, NULL, 0, sysctl_switch_tls, "",
3752 "Switch TCP connection to SW TLS");
3753 SYSCTL_PROC(_net_inet_tcp, OID_AUTO, switch_to_ifnet_tls,
3754 CTLFLAG_VNET | CTLTYPE_STRUCT | CTLFLAG_WR | CTLFLAG_SKIP |
3755 CTLFLAG_NEEDGIANT, NULL, 1, sysctl_switch_tls, "",
3756 "Switch TCP connection to ifnet TLS");
3757 #endif
3758
3759 /*
3760 * Generate a standardized TCP log line for use throughout the
3761 * tcp subsystem. Memory allocation is done with M_NOWAIT to
3762 * allow use in the interrupt context.
3763 *
3764 * NB: The caller MUST free(s, M_TCPLOG) the returned string.
3765 * NB: The function may return NULL if memory allocation failed.
3766 *
3767 * Due to header inclusion and ordering limitations the struct ip
3768 * and ip6_hdr pointers have to be passed as void pointers.
3769 */
3770 char *
tcp_log_vain(struct in_conninfo * inc,struct tcphdr * th,const void * ip4hdr,const void * ip6hdr)3771 tcp_log_vain(struct in_conninfo *inc, struct tcphdr *th, const void *ip4hdr,
3772 const void *ip6hdr)
3773 {
3774
3775 /* Is logging enabled? */
3776 if (V_tcp_log_in_vain == 0)
3777 return (NULL);
3778
3779 return (tcp_log_addr(inc, th, ip4hdr, ip6hdr));
3780 }
3781
3782 char *
tcp_log_addrs(struct in_conninfo * inc,struct tcphdr * th,const void * ip4hdr,const void * ip6hdr)3783 tcp_log_addrs(struct in_conninfo *inc, struct tcphdr *th, const void *ip4hdr,
3784 const void *ip6hdr)
3785 {
3786
3787 /* Is logging enabled? */
3788 if (tcp_log_debug == 0)
3789 return (NULL);
3790
3791 return (tcp_log_addr(inc, th, ip4hdr, ip6hdr));
3792 }
3793
3794 static char *
tcp_log_addr(struct in_conninfo * inc,struct tcphdr * th,const void * ip4hdr,const void * ip6hdr)3795 tcp_log_addr(struct in_conninfo *inc, struct tcphdr *th, const void *ip4hdr,
3796 const void *ip6hdr)
3797 {
3798 char *s, *sp;
3799 size_t size;
3800 #ifdef INET
3801 const struct ip *ip = (const struct ip *)ip4hdr;
3802 #endif
3803 #ifdef INET6
3804 const struct ip6_hdr *ip6 = (const struct ip6_hdr *)ip6hdr;
3805 #endif /* INET6 */
3806
3807 /*
3808 * The log line looks like this:
3809 * "TCP: [1.2.3.4]:50332 to [1.2.3.4]:80 tcpflags 0x2<SYN>"
3810 */
3811 size = sizeof("TCP: []:12345 to []:12345 tcpflags 0x2<>") +
3812 sizeof(PRINT_TH_FLAGS) + 1 +
3813 #ifdef INET6
3814 2 * INET6_ADDRSTRLEN;
3815 #else
3816 2 * INET_ADDRSTRLEN;
3817 #endif /* INET6 */
3818
3819 s = malloc(size, M_TCPLOG, M_ZERO|M_NOWAIT);
3820 if (s == NULL)
3821 return (NULL);
3822
3823 strcat(s, "TCP: [");
3824 sp = s + strlen(s);
3825
3826 if (inc && ((inc->inc_flags & INC_ISIPV6) == 0)) {
3827 inet_ntoa_r(inc->inc_faddr, sp);
3828 sp = s + strlen(s);
3829 sprintf(sp, "]:%i to [", ntohs(inc->inc_fport));
3830 sp = s + strlen(s);
3831 inet_ntoa_r(inc->inc_laddr, sp);
3832 sp = s + strlen(s);
3833 sprintf(sp, "]:%i", ntohs(inc->inc_lport));
3834 #ifdef INET6
3835 } else if (inc) {
3836 ip6_sprintf(sp, &inc->inc6_faddr);
3837 sp = s + strlen(s);
3838 sprintf(sp, "]:%i to [", ntohs(inc->inc_fport));
3839 sp = s + strlen(s);
3840 ip6_sprintf(sp, &inc->inc6_laddr);
3841 sp = s + strlen(s);
3842 sprintf(sp, "]:%i", ntohs(inc->inc_lport));
3843 } else if (ip6 && th) {
3844 ip6_sprintf(sp, &ip6->ip6_src);
3845 sp = s + strlen(s);
3846 sprintf(sp, "]:%i to [", ntohs(th->th_sport));
3847 sp = s + strlen(s);
3848 ip6_sprintf(sp, &ip6->ip6_dst);
3849 sp = s + strlen(s);
3850 sprintf(sp, "]:%i", ntohs(th->th_dport));
3851 #endif /* INET6 */
3852 #ifdef INET
3853 } else if (ip && th) {
3854 inet_ntoa_r(ip->ip_src, sp);
3855 sp = s + strlen(s);
3856 sprintf(sp, "]:%i to [", ntohs(th->th_sport));
3857 sp = s + strlen(s);
3858 inet_ntoa_r(ip->ip_dst, sp);
3859 sp = s + strlen(s);
3860 sprintf(sp, "]:%i", ntohs(th->th_dport));
3861 #endif /* INET */
3862 } else {
3863 free(s, M_TCPLOG);
3864 return (NULL);
3865 }
3866 sp = s + strlen(s);
3867 if (th)
3868 sprintf(sp, " tcpflags 0x%b", tcp_get_flags(th), PRINT_TH_FLAGS);
3869 if (*(s + size - 1) != '\0')
3870 panic("%s: string too long", __func__);
3871 return (s);
3872 }
3873
3874 /*
3875 * A subroutine which makes it easy to track TCP state changes with DTrace.
3876 * This function shouldn't be called for t_state initializations that don't
3877 * correspond to actual TCP state transitions.
3878 */
3879 void
tcp_state_change(struct tcpcb * tp,int newstate)3880 tcp_state_change(struct tcpcb *tp, int newstate)
3881 {
3882 #if defined(KDTRACE_HOOKS)
3883 int pstate = tp->t_state;
3884 #endif
3885
3886 TCPSTATES_DEC(tp->t_state);
3887 TCPSTATES_INC(newstate);
3888 tp->t_state = newstate;
3889 TCP_PROBE6(state__change, NULL, tp, NULL, tp, NULL, pstate);
3890 }
3891
3892 /*
3893 * Create an external-format (``xtcpcb'') structure using the information in
3894 * the kernel-format tcpcb structure pointed to by tp. This is done to
3895 * reduce the spew of irrelevant information over this interface, to isolate
3896 * user code from changes in the kernel structure, and potentially to provide
3897 * information-hiding if we decide that some of this information should be
3898 * hidden from users.
3899 */
3900 void
tcp_inptoxtp(const struct inpcb * inp,struct xtcpcb * xt)3901 tcp_inptoxtp(const struct inpcb *inp, struct xtcpcb *xt)
3902 {
3903 struct tcpcb *tp = intotcpcb(inp);
3904 sbintime_t now;
3905
3906 bzero(xt, sizeof(*xt));
3907 xt->t_state = tp->t_state;
3908 xt->t_logstate = tcp_get_bblog_state(tp);
3909 xt->t_flags = tp->t_flags;
3910 xt->t_sndzerowin = tp->t_sndzerowin;
3911 xt->t_sndrexmitpack = tp->t_sndrexmitpack;
3912 xt->t_rcvoopack = tp->t_rcvoopack;
3913 xt->t_rcv_wnd = tp->rcv_wnd;
3914 xt->t_snd_wnd = tp->snd_wnd;
3915 xt->t_snd_cwnd = tp->snd_cwnd;
3916 xt->t_snd_ssthresh = tp->snd_ssthresh;
3917 xt->t_dsack_bytes = tp->t_dsack_bytes;
3918 xt->t_dsack_tlp_bytes = tp->t_dsack_tlp_bytes;
3919 xt->t_dsack_pack = tp->t_dsack_pack;
3920 xt->t_maxseg = tp->t_maxseg;
3921 xt->xt_ecn = (tp->t_flags2 & TF2_ECN_PERMIT) ? 1 : 0 +
3922 (tp->t_flags2 & TF2_ACE_PERMIT) ? 2 : 0;
3923
3924 now = getsbinuptime();
3925 #define COPYTIMER(which,where) do { \
3926 if (tp->t_timers[which] != SBT_MAX) \
3927 xt->where = (tp->t_timers[which] - now) / SBT_1MS; \
3928 else \
3929 xt->where = 0; \
3930 } while (0)
3931 COPYTIMER(TT_DELACK, tt_delack);
3932 COPYTIMER(TT_REXMT, tt_rexmt);
3933 COPYTIMER(TT_PERSIST, tt_persist);
3934 COPYTIMER(TT_KEEP, tt_keep);
3935 COPYTIMER(TT_2MSL, tt_2msl);
3936 #undef COPYTIMER
3937 xt->t_rcvtime = 1000 * (ticks - tp->t_rcvtime) / hz;
3938
3939 xt->xt_encaps_port = tp->t_port;
3940 bcopy(tp->t_fb->tfb_tcp_block_name, xt->xt_stack,
3941 TCP_FUNCTION_NAME_LEN_MAX);
3942 bcopy(CC_ALGO(tp)->name, xt->xt_cc, TCP_CA_NAME_MAX);
3943 #ifdef TCP_BLACKBOX
3944 (void)tcp_log_get_id(tp, xt->xt_logid);
3945 #endif
3946
3947 xt->xt_len = sizeof(struct xtcpcb);
3948 in_pcbtoxinpcb(inp, &xt->xt_inp);
3949 }
3950
3951 void
tcp_log_end_status(struct tcpcb * tp,uint8_t status)3952 tcp_log_end_status(struct tcpcb *tp, uint8_t status)
3953 {
3954 uint32_t bit, i;
3955
3956 if ((tp == NULL) ||
3957 (status > TCP_EI_STATUS_MAX_VALUE) ||
3958 (status == 0)) {
3959 /* Invalid */
3960 return;
3961 }
3962 if (status > (sizeof(uint32_t) * 8)) {
3963 /* Should this be a KASSERT? */
3964 return;
3965 }
3966 bit = 1U << (status - 1);
3967 if (bit & tp->t_end_info_status) {
3968 /* already logged */
3969 return;
3970 }
3971 for (i = 0; i < TCP_END_BYTE_INFO; i++) {
3972 if (tp->t_end_info_bytes[i] == TCP_EI_EMPTY_SLOT) {
3973 tp->t_end_info_bytes[i] = status;
3974 tp->t_end_info_status |= bit;
3975 break;
3976 }
3977 }
3978 }
3979
3980 int
tcp_can_enable_pacing(void)3981 tcp_can_enable_pacing(void)
3982 {
3983
3984 if ((tcp_pacing_limit == -1) ||
3985 (tcp_pacing_limit > number_of_tcp_connections_pacing)) {
3986 atomic_fetchadd_int(&number_of_tcp_connections_pacing, 1);
3987 shadow_num_connections = number_of_tcp_connections_pacing;
3988 return (1);
3989 } else {
3990 counter_u64_add(tcp_pacing_failures, 1);
3991 return (0);
3992 }
3993 }
3994
3995 int
tcp_incr_dgp_pacing_cnt(void)3996 tcp_incr_dgp_pacing_cnt(void)
3997 {
3998 if ((tcp_dgp_limit == -1) ||
3999 (tcp_dgp_limit > number_of_dgp_connections)) {
4000 atomic_fetchadd_int(&number_of_dgp_connections, 1);
4001 shadow_tcp_pacing_dgp = number_of_dgp_connections;
4002 return (1);
4003 } else {
4004 counter_u64_add(tcp_dgp_failures, 1);
4005 return (0);
4006 }
4007 }
4008
4009 static uint8_t tcp_dgp_warning = 0;
4010
4011 void
tcp_dec_dgp_pacing_cnt(void)4012 tcp_dec_dgp_pacing_cnt(void)
4013 {
4014 uint32_t ret;
4015
4016 ret = atomic_fetchadd_int(&number_of_dgp_connections, -1);
4017 shadow_tcp_pacing_dgp = number_of_dgp_connections;
4018 KASSERT(ret != 0, ("number_of_dgp_connections -1 would cause wrap?"));
4019 if (ret == 0) {
4020 if (tcp_dgp_limit != -1) {
4021 printf("Warning all DGP is now disabled, count decrements invalidly!\n");
4022 tcp_dgp_limit = 0;
4023 tcp_dgp_warning = 1;
4024 } else if (tcp_dgp_warning == 0) {
4025 printf("Warning DGP pacing is invalid, invalid decrement\n");
4026 tcp_dgp_warning = 1;
4027 }
4028 }
4029
4030 }
4031
4032 static uint8_t tcp_pacing_warning = 0;
4033
4034 void
tcp_decrement_paced_conn(void)4035 tcp_decrement_paced_conn(void)
4036 {
4037 uint32_t ret;
4038
4039 ret = atomic_fetchadd_int(&number_of_tcp_connections_pacing, -1);
4040 shadow_num_connections = number_of_tcp_connections_pacing;
4041 KASSERT(ret != 0, ("tcp_paced_connection_exits -1 would cause wrap?"));
4042 if (ret == 0) {
4043 if (tcp_pacing_limit != -1) {
4044 printf("Warning all pacing is now disabled, count decrements invalidly!\n");
4045 tcp_pacing_limit = 0;
4046 } else if (tcp_pacing_warning == 0) {
4047 printf("Warning pacing count is invalid, invalid decrement\n");
4048 tcp_pacing_warning = 1;
4049 }
4050 }
4051 }
4052
4053 static void
tcp_default_switch_failed(struct tcpcb * tp)4054 tcp_default_switch_failed(struct tcpcb *tp)
4055 {
4056 /*
4057 * If a switch fails we only need to
4058 * care about two things:
4059 * a) The t_flags2
4060 * and
4061 * b) The timer granularity.
4062 * Timeouts, at least for now, don't use the
4063 * old callout system in the other stacks so
4064 * those are hopefully safe.
4065 */
4066 tcp_lro_features_off(tp);
4067 tcp_change_time_units(tp, TCP_TMR_GRANULARITY_TICKS);
4068 }
4069
4070 #ifdef TCP_ACCOUNTING
4071 int
tcp_do_ack_accounting(struct tcpcb * tp,struct tcphdr * th,struct tcpopt * to,uint32_t tiwin,int mss)4072 tcp_do_ack_accounting(struct tcpcb *tp, struct tcphdr *th, struct tcpopt *to, uint32_t tiwin, int mss)
4073 {
4074 if (SEQ_LT(th->th_ack, tp->snd_una)) {
4075 /* Do we have a SACK? */
4076 if (to->to_flags & TOF_SACK) {
4077 if (tp->t_flags2 & TF2_TCP_ACCOUNTING) {
4078 tp->tcp_cnt_counters[ACK_SACK]++;
4079 }
4080 return (ACK_SACK);
4081 } else {
4082 if (tp->t_flags2 & TF2_TCP_ACCOUNTING) {
4083 tp->tcp_cnt_counters[ACK_BEHIND]++;
4084 }
4085 return (ACK_BEHIND);
4086 }
4087 } else if (th->th_ack == tp->snd_una) {
4088 /* Do we have a SACK? */
4089 if (to->to_flags & TOF_SACK) {
4090 if (tp->t_flags2 & TF2_TCP_ACCOUNTING) {
4091 tp->tcp_cnt_counters[ACK_SACK]++;
4092 }
4093 return (ACK_SACK);
4094 } else if (tiwin != tp->snd_wnd) {
4095 if (tp->t_flags2 & TF2_TCP_ACCOUNTING) {
4096 tp->tcp_cnt_counters[ACK_RWND]++;
4097 }
4098 return (ACK_RWND);
4099 } else {
4100 if (tp->t_flags2 & TF2_TCP_ACCOUNTING) {
4101 tp->tcp_cnt_counters[ACK_DUPACK]++;
4102 }
4103 return (ACK_DUPACK);
4104 }
4105 } else {
4106 if (!SEQ_GT(th->th_ack, tp->snd_max)) {
4107 if (tp->t_flags2 & TF2_TCP_ACCOUNTING) {
4108 tp->tcp_cnt_counters[CNT_OF_ACKS_IN] += (((th->th_ack - tp->snd_una) + mss - 1)/mss);
4109 }
4110 }
4111 if (to->to_flags & TOF_SACK) {
4112 if (tp->t_flags2 & TF2_TCP_ACCOUNTING) {
4113 tp->tcp_cnt_counters[ACK_CUMACK_SACK]++;
4114 }
4115 return (ACK_CUMACK_SACK);
4116 } else {
4117 if (tp->t_flags2 & TF2_TCP_ACCOUNTING) {
4118 tp->tcp_cnt_counters[ACK_CUMACK]++;
4119 }
4120 return (ACK_CUMACK);
4121 }
4122 }
4123 }
4124 #endif
4125
4126 void
tcp_change_time_units(struct tcpcb * tp,int granularity)4127 tcp_change_time_units(struct tcpcb *tp, int granularity)
4128 {
4129 if (tp->t_tmr_granularity == granularity) {
4130 /* We are there */
4131 return;
4132 }
4133 if (granularity == TCP_TMR_GRANULARITY_USEC) {
4134 KASSERT((tp->t_tmr_granularity == TCP_TMR_GRANULARITY_TICKS),
4135 ("Granularity is not TICKS its %u in tp:%p",
4136 tp->t_tmr_granularity, tp));
4137 tp->t_rttlow = TICKS_2_USEC(tp->t_rttlow);
4138 if (tp->t_srtt > 1) {
4139 uint32_t val, frac;
4140
4141 val = tp->t_srtt >> TCP_RTT_SHIFT;
4142 frac = tp->t_srtt & 0x1f;
4143 tp->t_srtt = TICKS_2_USEC(val);
4144 /*
4145 * frac is the fractional part of the srtt (if any)
4146 * but its in ticks and every bit represents
4147 * 1/32nd of a hz.
4148 */
4149 if (frac) {
4150 if (hz == 1000) {
4151 frac = (((uint64_t)frac * (uint64_t)HPTS_USEC_IN_MSEC) / (uint64_t)TCP_RTT_SCALE);
4152 } else {
4153 frac = (((uint64_t)frac * (uint64_t)HPTS_USEC_IN_SEC) / ((uint64_t)(hz) * (uint64_t)TCP_RTT_SCALE));
4154 }
4155 tp->t_srtt += frac;
4156 }
4157 }
4158 if (tp->t_rttvar) {
4159 uint32_t val, frac;
4160
4161 val = tp->t_rttvar >> TCP_RTTVAR_SHIFT;
4162 frac = tp->t_rttvar & 0x1f;
4163 tp->t_rttvar = TICKS_2_USEC(val);
4164 /*
4165 * frac is the fractional part of the srtt (if any)
4166 * but its in ticks and every bit represents
4167 * 1/32nd of a hz.
4168 */
4169 if (frac) {
4170 if (hz == 1000) {
4171 frac = (((uint64_t)frac * (uint64_t)HPTS_USEC_IN_MSEC) / (uint64_t)TCP_RTT_SCALE);
4172 } else {
4173 frac = (((uint64_t)frac * (uint64_t)HPTS_USEC_IN_SEC) / ((uint64_t)(hz) * (uint64_t)TCP_RTT_SCALE));
4174 }
4175 tp->t_rttvar += frac;
4176 }
4177 }
4178 tp->t_tmr_granularity = TCP_TMR_GRANULARITY_USEC;
4179 } else if (granularity == TCP_TMR_GRANULARITY_TICKS) {
4180 /* Convert back to ticks, with */
4181 KASSERT((tp->t_tmr_granularity == TCP_TMR_GRANULARITY_USEC),
4182 ("Granularity is not USEC its %u in tp:%p",
4183 tp->t_tmr_granularity, tp));
4184 if (tp->t_srtt > 1) {
4185 uint32_t val, frac;
4186
4187 val = USEC_2_TICKS(tp->t_srtt);
4188 frac = tp->t_srtt % (HPTS_USEC_IN_SEC / hz);
4189 tp->t_srtt = val << TCP_RTT_SHIFT;
4190 /*
4191 * frac is the fractional part here is left
4192 * over from converting to hz and shifting.
4193 * We need to convert this to the 5 bit
4194 * remainder.
4195 */
4196 if (frac) {
4197 if (hz == 1000) {
4198 frac = (((uint64_t)frac * (uint64_t)TCP_RTT_SCALE) / (uint64_t)HPTS_USEC_IN_MSEC);
4199 } else {
4200 frac = (((uint64_t)frac * (uint64_t)(hz) * (uint64_t)TCP_RTT_SCALE) /(uint64_t)HPTS_USEC_IN_SEC);
4201 }
4202 tp->t_srtt += frac;
4203 }
4204 }
4205 if (tp->t_rttvar) {
4206 uint32_t val, frac;
4207
4208 val = USEC_2_TICKS(tp->t_rttvar);
4209 frac = tp->t_rttvar % (HPTS_USEC_IN_SEC / hz);
4210 tp->t_rttvar = val << TCP_RTTVAR_SHIFT;
4211 /*
4212 * frac is the fractional part here is left
4213 * over from converting to hz and shifting.
4214 * We need to convert this to the 4 bit
4215 * remainder.
4216 */
4217 if (frac) {
4218 if (hz == 1000) {
4219 frac = (((uint64_t)frac * (uint64_t)TCP_RTTVAR_SCALE) / (uint64_t)HPTS_USEC_IN_MSEC);
4220 } else {
4221 frac = (((uint64_t)frac * (uint64_t)(hz) * (uint64_t)TCP_RTTVAR_SCALE) /(uint64_t)HPTS_USEC_IN_SEC);
4222 }
4223 tp->t_rttvar += frac;
4224 }
4225 }
4226 tp->t_rttlow = USEC_2_TICKS(tp->t_rttlow);
4227 tp->t_tmr_granularity = TCP_TMR_GRANULARITY_TICKS;
4228 }
4229 #ifdef INVARIANTS
4230 else {
4231 panic("Unknown granularity:%d tp:%p",
4232 granularity, tp);
4233 }
4234 #endif
4235 }
4236
4237 void
tcp_handle_orphaned_packets(struct tcpcb * tp)4238 tcp_handle_orphaned_packets(struct tcpcb *tp)
4239 {
4240 struct mbuf *save, *m, *prev;
4241 /*
4242 * Called when a stack switch is occuring from the fini()
4243 * of the old stack. We assue the init() as already been
4244 * run of the new stack and it has set the t_flags2 to
4245 * what it supports. This function will then deal with any
4246 * differences i.e. cleanup packets that maybe queued that
4247 * the newstack does not support.
4248 */
4249
4250 if (tp->t_flags2 & TF2_MBUF_L_ACKS)
4251 return;
4252 if ((tp->t_flags2 & TF2_SUPPORTS_MBUFQ) == 0 &&
4253 !STAILQ_EMPTY(&tp->t_inqueue)) {
4254 /*
4255 * It is unsafe to process the packets since a
4256 * reset may be lurking in them (its rare but it
4257 * can occur). If we were to find a RST, then we
4258 * would end up dropping the connection and the
4259 * INP lock, so when we return the caller (tcp_usrreq)
4260 * will blow up when it trys to unlock the inp.
4261 * This new stack does not do any fancy LRO features
4262 * so all we can do is toss the packets.
4263 */
4264 m = STAILQ_FIRST(&tp->t_inqueue);
4265 STAILQ_INIT(&tp->t_inqueue);
4266 STAILQ_FOREACH_FROM_SAFE(m, &tp->t_inqueue, m_stailqpkt, save)
4267 m_freem(m);
4268 } else {
4269 /*
4270 * Here we have a stack that does mbuf queuing but
4271 * does not support compressed ack's. We must
4272 * walk all the mbufs and discard any compressed acks.
4273 */
4274 STAILQ_FOREACH_SAFE(m, &tp->t_inqueue, m_stailqpkt, save) {
4275 if (m->m_flags & M_ACKCMP) {
4276 if (m == STAILQ_FIRST(&tp->t_inqueue))
4277 STAILQ_REMOVE_HEAD(&tp->t_inqueue,
4278 m_stailqpkt);
4279 else
4280 STAILQ_REMOVE_AFTER(&tp->t_inqueue,
4281 prev, m_stailqpkt);
4282 m_freem(m);
4283 } else
4284 prev = m;
4285 }
4286 }
4287 }
4288
4289 #ifdef TCP_REQUEST_TRK
4290 uint32_t
tcp_estimate_tls_overhead(struct socket * so,uint64_t tls_usr_bytes)4291 tcp_estimate_tls_overhead(struct socket *so, uint64_t tls_usr_bytes)
4292 {
4293 #ifdef KERN_TLS
4294 struct ktls_session *tls;
4295 uint32_t rec_oh, records;
4296
4297 tls = so->so_snd.sb_tls_info;
4298 if (tls == NULL)
4299 return (0);
4300
4301 rec_oh = tls->params.tls_hlen + tls->params.tls_tlen;
4302 records = ((tls_usr_bytes + tls->params.max_frame_len - 1)/tls->params.max_frame_len);
4303 return (records * rec_oh);
4304 #else
4305 return (0);
4306 #endif
4307 }
4308
4309 extern uint32_t tcp_stale_entry_time;
4310 uint32_t tcp_stale_entry_time = 250000;
4311 SYSCTL_UINT(_net_inet_tcp, OID_AUTO, usrlog_stale, CTLFLAG_RW,
4312 &tcp_stale_entry_time, 250000, "Time that a tcpreq entry without a sendfile ages out");
4313
4314 void
tcp_req_log_req_info(struct tcpcb * tp,struct tcp_sendfile_track * req,uint16_t slot,uint8_t val,uint64_t offset,uint64_t nbytes)4315 tcp_req_log_req_info(struct tcpcb *tp, struct tcp_sendfile_track *req,
4316 uint16_t slot, uint8_t val, uint64_t offset, uint64_t nbytes)
4317 {
4318 if (tcp_bblogging_on(tp)) {
4319 union tcp_log_stackspecific log;
4320 struct timeval tv;
4321
4322 memset(&log.u_bbr, 0, sizeof(log.u_bbr));
4323 log.u_bbr.inhpts = tcp_in_hpts(tp);
4324 log.u_bbr.flex8 = val;
4325 log.u_bbr.rttProp = req->timestamp;
4326 log.u_bbr.delRate = req->start;
4327 log.u_bbr.cur_del_rate = req->end;
4328 log.u_bbr.flex1 = req->start_seq;
4329 log.u_bbr.flex2 = req->end_seq;
4330 log.u_bbr.flex3 = req->flags;
4331 log.u_bbr.flex4 = ((req->localtime >> 32) & 0x00000000ffffffff);
4332 log.u_bbr.flex5 = (req->localtime & 0x00000000ffffffff);
4333 log.u_bbr.flex7 = slot;
4334 log.u_bbr.bw_inuse = offset;
4335 /* nbytes = flex6 | epoch */
4336 log.u_bbr.flex6 = ((nbytes >> 32) & 0x00000000ffffffff);
4337 log.u_bbr.epoch = (nbytes & 0x00000000ffffffff);
4338 /* cspr = lt_epoch | pkts_out */
4339 log.u_bbr.lt_epoch = ((req->cspr >> 32) & 0x00000000ffffffff);
4340 log.u_bbr.pkts_out |= (req->cspr & 0x00000000ffffffff);
4341 log.u_bbr.applimited = tp->t_tcpreq_closed;
4342 log.u_bbr.applimited <<= 8;
4343 log.u_bbr.applimited |= tp->t_tcpreq_open;
4344 log.u_bbr.applimited <<= 8;
4345 log.u_bbr.applimited |= tp->t_tcpreq_req;
4346 log.u_bbr.timeStamp = tcp_get_usecs(&tv);
4347 TCP_LOG_EVENTP(tp, NULL,
4348 &tptosocket(tp)->so_rcv,
4349 &tptosocket(tp)->so_snd,
4350 TCP_LOG_REQ_T, 0,
4351 0, &log, false, &tv);
4352 }
4353 }
4354
4355 void
tcp_req_free_a_slot(struct tcpcb * tp,struct tcp_sendfile_track * ent)4356 tcp_req_free_a_slot(struct tcpcb *tp, struct tcp_sendfile_track *ent)
4357 {
4358 if (tp->t_tcpreq_req > 0)
4359 tp->t_tcpreq_req--;
4360 if (ent->flags & TCP_TRK_TRACK_FLG_OPEN) {
4361 if (tp->t_tcpreq_open > 0)
4362 tp->t_tcpreq_open--;
4363 } else {
4364 if (tp->t_tcpreq_closed > 0)
4365 tp->t_tcpreq_closed--;
4366 }
4367 ent->flags = TCP_TRK_TRACK_FLG_EMPTY;
4368 }
4369
4370 static void
tcp_req_check_for_stale_entries(struct tcpcb * tp,uint64_t ts,int rm_oldest)4371 tcp_req_check_for_stale_entries(struct tcpcb *tp, uint64_t ts, int rm_oldest)
4372 {
4373 struct tcp_sendfile_track *ent;
4374 uint64_t time_delta, oldest_delta;
4375 int i, oldest, oldest_set = 0, cnt_rm = 0;
4376
4377 for(i = 0; i < MAX_TCP_TRK_REQ; i++) {
4378 ent = &tp->t_tcpreq_info[i];
4379 if (ent->flags != TCP_TRK_TRACK_FLG_USED) {
4380 /*
4381 * We only care about closed end ranges
4382 * that are allocated and have no sendfile
4383 * ever touching them. They would be in
4384 * state USED.
4385 */
4386 continue;
4387 }
4388 if (ts >= ent->localtime)
4389 time_delta = ts - ent->localtime;
4390 else
4391 time_delta = 0;
4392 if (time_delta &&
4393 ((oldest_delta < time_delta) || (oldest_set == 0))) {
4394 oldest_set = 1;
4395 oldest = i;
4396 oldest_delta = time_delta;
4397 }
4398 if (tcp_stale_entry_time && (time_delta >= tcp_stale_entry_time)) {
4399 /*
4400 * No sendfile in a our time-limit
4401 * time to purge it.
4402 */
4403 cnt_rm++;
4404 tcp_req_log_req_info(tp, &tp->t_tcpreq_info[i], i, TCP_TRK_REQ_LOG_STALE,
4405 time_delta, 0);
4406 tcp_req_free_a_slot(tp, ent);
4407 }
4408 }
4409 if ((cnt_rm == 0) && rm_oldest && oldest_set) {
4410 ent = &tp->t_tcpreq_info[oldest];
4411 tcp_req_log_req_info(tp, &tp->t_tcpreq_info[i], i, TCP_TRK_REQ_LOG_STALE,
4412 oldest_delta, 1);
4413 tcp_req_free_a_slot(tp, ent);
4414 }
4415 }
4416
4417 int
tcp_req_check_for_comp(struct tcpcb * tp,tcp_seq ack_point)4418 tcp_req_check_for_comp(struct tcpcb *tp, tcp_seq ack_point)
4419 {
4420 int i, ret=0;
4421 struct tcp_sendfile_track *ent;
4422
4423 /* Clean up any old closed end requests that are now completed */
4424 if (tp->t_tcpreq_req == 0)
4425 return(0);
4426 if (tp->t_tcpreq_closed == 0)
4427 return(0);
4428 for(i = 0; i < MAX_TCP_TRK_REQ; i++) {
4429 ent = &tp->t_tcpreq_info[i];
4430 /* Skip empty ones */
4431 if (ent->flags == TCP_TRK_TRACK_FLG_EMPTY)
4432 continue;
4433 /* Skip open ones */
4434 if (ent->flags & TCP_TRK_TRACK_FLG_OPEN)
4435 continue;
4436 if (SEQ_GEQ(ack_point, ent->end_seq)) {
4437 /* We are past it -- free it */
4438 tcp_req_log_req_info(tp, ent,
4439 i, TCP_TRK_REQ_LOG_FREED, 0, 0);
4440 tcp_req_free_a_slot(tp, ent);
4441 ret++;
4442 }
4443 }
4444 return (ret);
4445 }
4446
4447 int
tcp_req_is_entry_comp(struct tcpcb * tp,struct tcp_sendfile_track * ent,tcp_seq ack_point)4448 tcp_req_is_entry_comp(struct tcpcb *tp, struct tcp_sendfile_track *ent, tcp_seq ack_point)
4449 {
4450 if (tp->t_tcpreq_req == 0)
4451 return(-1);
4452 if (tp->t_tcpreq_closed == 0)
4453 return(-1);
4454 if (ent->flags == TCP_TRK_TRACK_FLG_EMPTY)
4455 return(-1);
4456 if (SEQ_GEQ(ack_point, ent->end_seq)) {
4457 return (1);
4458 }
4459 return (0);
4460 }
4461
4462 struct tcp_sendfile_track *
tcp_req_find_a_req_that_is_completed_by(struct tcpcb * tp,tcp_seq th_ack,int * ip)4463 tcp_req_find_a_req_that_is_completed_by(struct tcpcb *tp, tcp_seq th_ack, int *ip)
4464 {
4465 /*
4466 * Given an ack point (th_ack) walk through our entries and
4467 * return the first one found that th_ack goes past the
4468 * end_seq.
4469 */
4470 struct tcp_sendfile_track *ent;
4471 int i;
4472
4473 if (tp->t_tcpreq_req == 0) {
4474 /* none open */
4475 return (NULL);
4476 }
4477 for(i = 0; i < MAX_TCP_TRK_REQ; i++) {
4478 ent = &tp->t_tcpreq_info[i];
4479 if (ent->flags == TCP_TRK_TRACK_FLG_EMPTY)
4480 continue;
4481 if ((ent->flags & TCP_TRK_TRACK_FLG_OPEN) == 0) {
4482 if (SEQ_GEQ(th_ack, ent->end_seq)) {
4483 *ip = i;
4484 return (ent);
4485 }
4486 }
4487 }
4488 return (NULL);
4489 }
4490
4491 struct tcp_sendfile_track *
tcp_req_find_req_for_seq(struct tcpcb * tp,tcp_seq seq)4492 tcp_req_find_req_for_seq(struct tcpcb *tp, tcp_seq seq)
4493 {
4494 struct tcp_sendfile_track *ent;
4495 int i;
4496
4497 if (tp->t_tcpreq_req == 0) {
4498 /* none open */
4499 return (NULL);
4500 }
4501 for(i = 0; i < MAX_TCP_TRK_REQ; i++) {
4502 ent = &tp->t_tcpreq_info[i];
4503 tcp_req_log_req_info(tp, ent, i, TCP_TRK_REQ_LOG_SEARCH,
4504 (uint64_t)seq, 0);
4505 if (ent->flags == TCP_TRK_TRACK_FLG_EMPTY) {
4506 continue;
4507 }
4508 if (ent->flags & TCP_TRK_TRACK_FLG_OPEN) {
4509 /*
4510 * An open end request only needs to
4511 * match the beginning seq or be
4512 * all we have (once we keep going on
4513 * a open end request we may have a seq
4514 * wrap).
4515 */
4516 if ((SEQ_GEQ(seq, ent->start_seq)) ||
4517 (tp->t_tcpreq_closed == 0))
4518 return (ent);
4519 } else {
4520 /*
4521 * For this one we need to
4522 * be a bit more careful if its
4523 * completed at least.
4524 */
4525 if ((SEQ_GEQ(seq, ent->start_seq)) &&
4526 (SEQ_LT(seq, ent->end_seq))) {
4527 return (ent);
4528 }
4529 }
4530 }
4531 return (NULL);
4532 }
4533
4534 /* Should this be in its own file tcp_req.c ? */
4535 struct tcp_sendfile_track *
tcp_req_alloc_req_full(struct tcpcb * tp,struct tcp_snd_req * req,uint64_t ts,int rec_dups)4536 tcp_req_alloc_req_full(struct tcpcb *tp, struct tcp_snd_req *req, uint64_t ts, int rec_dups)
4537 {
4538 struct tcp_sendfile_track *fil;
4539 int i, allocated;
4540
4541 /* In case the stack does not check for completions do so now */
4542 tcp_req_check_for_comp(tp, tp->snd_una);
4543 /* Check for stale entries */
4544 if (tp->t_tcpreq_req)
4545 tcp_req_check_for_stale_entries(tp, ts,
4546 (tp->t_tcpreq_req >= MAX_TCP_TRK_REQ));
4547 /* Check to see if this is a duplicate of one not started */
4548 if (tp->t_tcpreq_req) {
4549 for(i = 0, allocated = 0; i < MAX_TCP_TRK_REQ; i++) {
4550 fil = &tp->t_tcpreq_info[i];
4551 if ((fil->flags & TCP_TRK_TRACK_FLG_USED) == 0)
4552 continue;
4553 if ((fil->timestamp == req->timestamp) &&
4554 (fil->start == req->start) &&
4555 ((fil->flags & TCP_TRK_TRACK_FLG_OPEN) ||
4556 (fil->end == req->end))) {
4557 /*
4558 * We already have this request
4559 * and it has not been started with sendfile.
4560 * This probably means the user was returned
4561 * a 4xx of some sort and its going to age
4562 * out, lets not duplicate it.
4563 */
4564 return(fil);
4565 }
4566 }
4567 }
4568 /* Ok if there is no room at the inn we are in trouble */
4569 if (tp->t_tcpreq_req >= MAX_TCP_TRK_REQ) {
4570 tcp_trace_point(tp, TCP_TP_REQ_LOG_FAIL);
4571 for(i = 0; i < MAX_TCP_TRK_REQ; i++) {
4572 tcp_req_log_req_info(tp, &tp->t_tcpreq_info[i],
4573 i, TCP_TRK_REQ_LOG_ALLOCFAIL, 0, 0);
4574 }
4575 return (NULL);
4576 }
4577 for(i = 0, allocated = 0; i < MAX_TCP_TRK_REQ; i++) {
4578 fil = &tp->t_tcpreq_info[i];
4579 if (fil->flags == TCP_TRK_TRACK_FLG_EMPTY) {
4580 allocated = 1;
4581 fil->flags = TCP_TRK_TRACK_FLG_USED;
4582 fil->timestamp = req->timestamp;
4583 fil->playout_ms = req->playout_ms;
4584 fil->localtime = ts;
4585 fil->start = req->start;
4586 if (req->flags & TCP_LOG_HTTPD_RANGE_END) {
4587 fil->end = req->end;
4588 } else {
4589 fil->end = 0;
4590 fil->flags |= TCP_TRK_TRACK_FLG_OPEN;
4591 }
4592 /*
4593 * We can set the min boundaries to the TCP Sequence space,
4594 * but it might be found to be further up when sendfile
4595 * actually runs on this range (if it ever does).
4596 */
4597 fil->sbcc_at_s = tptosocket(tp)->so_snd.sb_ccc;
4598 fil->start_seq = tp->snd_una +
4599 tptosocket(tp)->so_snd.sb_ccc;
4600 if (req->flags & TCP_LOG_HTTPD_RANGE_END)
4601 fil->end_seq = (fil->start_seq + ((uint32_t)(fil->end - fil->start)));
4602 else
4603 fil->end_seq = 0;
4604 if (tptosocket(tp)->so_snd.sb_tls_info) {
4605 /*
4606 * This session is doing TLS. Take a swag guess
4607 * at the overhead.
4608 */
4609 fil->end_seq += tcp_estimate_tls_overhead(
4610 tptosocket(tp), (fil->end - fil->start));
4611 }
4612 tp->t_tcpreq_req++;
4613 if (fil->flags & TCP_TRK_TRACK_FLG_OPEN)
4614 tp->t_tcpreq_open++;
4615 else
4616 tp->t_tcpreq_closed++;
4617 tcp_req_log_req_info(tp, fil, i,
4618 TCP_TRK_REQ_LOG_NEW, 0, 0);
4619 break;
4620 } else
4621 fil = NULL;
4622 }
4623 return (fil);
4624 }
4625
4626 void
tcp_req_alloc_req(struct tcpcb * tp,union tcp_log_userdata * user,uint64_t ts)4627 tcp_req_alloc_req(struct tcpcb *tp, union tcp_log_userdata *user, uint64_t ts)
4628 {
4629 (void)tcp_req_alloc_req_full(tp, &user->tcp_req, ts, 1);
4630 }
4631 #endif
4632
4633 void
tcp_log_socket_option(struct tcpcb * tp,uint32_t option_num,uint32_t option_val,int err)4634 tcp_log_socket_option(struct tcpcb *tp, uint32_t option_num, uint32_t option_val, int err)
4635 {
4636 if (tcp_bblogging_on(tp)) {
4637 struct tcp_log_buffer *l;
4638
4639 l = tcp_log_event(tp, NULL,
4640 &tptosocket(tp)->so_rcv,
4641 &tptosocket(tp)->so_snd,
4642 TCP_LOG_SOCKET_OPT,
4643 err, 0, NULL, 1,
4644 NULL, NULL, 0, NULL);
4645 if (l) {
4646 l->tlb_flex1 = option_num;
4647 l->tlb_flex2 = option_val;
4648 }
4649 }
4650 }
4651
4652 uint32_t
tcp_get_srtt(struct tcpcb * tp,int granularity)4653 tcp_get_srtt(struct tcpcb *tp, int granularity)
4654 {
4655 uint32_t srtt;
4656
4657 KASSERT(granularity == TCP_TMR_GRANULARITY_USEC ||
4658 granularity == TCP_TMR_GRANULARITY_TICKS,
4659 ("%s: called with unexpected granularity %d", __func__,
4660 granularity));
4661
4662 srtt = tp->t_srtt;
4663
4664 /*
4665 * We only support two granularities. If the stored granularity
4666 * does not match the granularity requested by the caller,
4667 * convert the stored value to the requested unit of granularity.
4668 */
4669 if (tp->t_tmr_granularity != granularity) {
4670 if (granularity == TCP_TMR_GRANULARITY_USEC)
4671 srtt = TICKS_2_USEC(srtt);
4672 else
4673 srtt = USEC_2_TICKS(srtt);
4674 }
4675
4676 /*
4677 * If the srtt is stored with ticks granularity, we need to
4678 * unshift to get the actual value. We do this after the
4679 * conversion above (if one was necessary) in order to maximize
4680 * precision.
4681 */
4682 if (tp->t_tmr_granularity == TCP_TMR_GRANULARITY_TICKS)
4683 srtt = srtt >> TCP_RTT_SHIFT;
4684
4685 return (srtt);
4686 }
4687
4688 void
tcp_account_for_send(struct tcpcb * tp,uint32_t len,uint8_t is_rxt,uint8_t is_tlp,bool hw_tls)4689 tcp_account_for_send(struct tcpcb *tp, uint32_t len, uint8_t is_rxt,
4690 uint8_t is_tlp, bool hw_tls)
4691 {
4692
4693 if (is_tlp) {
4694 tp->t_sndtlppack++;
4695 tp->t_sndtlpbyte += len;
4696 }
4697 /* To get total bytes sent you must add t_snd_rxt_bytes to t_sndbytes */
4698 if (is_rxt)
4699 tp->t_snd_rxt_bytes += len;
4700 else
4701 tp->t_sndbytes += len;
4702
4703 #ifdef KERN_TLS
4704 if (hw_tls && is_rxt && len != 0) {
4705 uint64_t rexmit_percent;
4706
4707 rexmit_percent = (1000ULL * tp->t_snd_rxt_bytes) /
4708 (10ULL * (tp->t_snd_rxt_bytes + tp->t_sndbytes));
4709 if (rexmit_percent > ktls_ifnet_max_rexmit_pct)
4710 ktls_disable_ifnet(tp);
4711 }
4712 #endif
4713 }
4714