xref: /freebsd/sys/netinet/toecore.c (revision 9f23cbd6cae82fd77edfad7173432fa8dccd0a95)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2012 Chelsio Communications, Inc.
5  * All rights reserved.
6  * Written by: Navdeep Parhar <np@FreeBSD.org>
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #include <sys/cdefs.h>
31 __FBSDID("$FreeBSD$");
32 
33 #include "opt_inet.h"
34 #include "opt_inet6.h"
35 
36 #include <sys/param.h>
37 #include <sys/eventhandler.h>
38 #include <sys/kernel.h>
39 #include <sys/systm.h>
40 #include <sys/malloc.h>
41 #include <sys/mbuf.h>
42 #include <sys/module.h>
43 #include <sys/types.h>
44 #include <sys/sockopt.h>
45 #include <sys/sysctl.h>
46 #include <sys/socket.h>
47 
48 #include <net/ethernet.h>
49 #include <net/if.h>
50 #include <net/if_var.h>
51 #include <net/if_private.h>
52 #include <net/if_types.h>
53 #include <net/if_vlan_var.h>
54 #include <net/if_llatbl.h>
55 #include <net/route.h>
56 
57 #include <netinet/if_ether.h>
58 #include <netinet/in.h>
59 #include <netinet/in_pcb.h>
60 #include <netinet/in_var.h>
61 #include <netinet6/in6_var.h>
62 #include <netinet6/in6_pcb.h>
63 #include <netinet6/nd6.h>
64 #define TCPSTATES
65 #include <netinet/tcp.h>
66 #include <netinet/tcp_fsm.h>
67 #include <netinet/tcp_timer.h>
68 #include <netinet/tcp_var.h>
69 #include <netinet/tcp_syncache.h>
70 #include <netinet/tcp_offload.h>
71 #include <netinet/toecore.h>
72 
73 static struct mtx toedev_lock;
74 static TAILQ_HEAD(, toedev) toedev_list;
75 static eventhandler_tag listen_start_eh;
76 static eventhandler_tag listen_stop_eh;
77 static eventhandler_tag lle_event_eh;
78 
79 static int
80 toedev_connect(struct toedev *tod __unused, struct socket *so __unused,
81     struct nhop_object *nh __unused, struct sockaddr *nam __unused)
82 {
83 
84 	return (ENOTSUP);
85 }
86 
87 static int
88 toedev_listen_start(struct toedev *tod __unused, struct tcpcb *tp __unused)
89 {
90 
91 	return (ENOTSUP);
92 }
93 
94 static int
95 toedev_listen_stop(struct toedev *tod __unused, struct tcpcb *tp __unused)
96 {
97 
98 	return (ENOTSUP);
99 }
100 
101 static void
102 toedev_input(struct toedev *tod __unused, struct tcpcb *tp __unused,
103     struct mbuf *m)
104 {
105 
106 	m_freem(m);
107 	return;
108 }
109 
110 static void
111 toedev_rcvd(struct toedev *tod __unused, struct tcpcb *tp __unused)
112 {
113 
114 	return;
115 }
116 
117 static int
118 toedev_output(struct toedev *tod __unused, struct tcpcb *tp __unused)
119 {
120 
121 	return (ENOTSUP);
122 }
123 
124 static void
125 toedev_pcb_detach(struct toedev *tod __unused, struct tcpcb *tp __unused)
126 {
127 
128 	return;
129 }
130 
131 static void
132 toedev_l2_update(struct toedev *tod __unused, struct ifnet *ifp __unused,
133     struct sockaddr *sa __unused, uint8_t *lladdr __unused,
134     uint16_t vtag __unused)
135 {
136 
137 	return;
138 }
139 
140 static void
141 toedev_route_redirect(struct toedev *tod __unused, struct ifnet *ifp __unused,
142     struct nhop_object *nh0 __unused, struct nhop_object *nh1 __unused)
143 {
144 
145 	return;
146 }
147 
148 static void
149 toedev_syncache_added(struct toedev *tod __unused, void *ctx __unused)
150 {
151 
152 	return;
153 }
154 
155 static void
156 toedev_syncache_removed(struct toedev *tod __unused, void *ctx __unused)
157 {
158 
159 	return;
160 }
161 
162 static int
163 toedev_syncache_respond(struct toedev *tod __unused, void *ctx __unused,
164     struct mbuf *m)
165 {
166 
167 	m_freem(m);
168 	return (0);
169 }
170 
171 static void
172 toedev_offload_socket(struct toedev *tod __unused, void *ctx __unused,
173     struct socket *so __unused)
174 {
175 
176 	return;
177 }
178 
179 static void
180 toedev_ctloutput(struct toedev *tod __unused, struct tcpcb *tp __unused,
181     int sopt_dir __unused, int sopt_name __unused)
182 {
183 
184 	return;
185 }
186 
187 static void
188 toedev_tcp_info(struct toedev *tod __unused, struct tcpcb *tp __unused,
189     struct tcp_info *ti __unused)
190 {
191 
192 	return;
193 }
194 
195 static int
196 toedev_alloc_tls_session(struct toedev *tod __unused, struct tcpcb *tp __unused,
197     struct ktls_session *tls __unused, int direction __unused)
198 {
199 
200 	return (EINVAL);
201 }
202 
203 static void
204 toedev_pmtu_update(struct toedev *tod __unused, struct tcpcb *tp __unused,
205     tcp_seq seq __unused, int mtu __unused)
206 {
207 
208 	return;
209 }
210 
211 /*
212  * Inform one or more TOE devices about a listening socket.
213  */
214 static void
215 toe_listen_start(struct inpcb *inp, void *arg)
216 {
217 	struct toedev *t, *tod;
218 	struct tcpcb *tp;
219 
220 	INP_WLOCK_ASSERT(inp);
221 	KASSERT(inp->inp_pcbinfo == &V_tcbinfo,
222 	    ("%s: inp is not a TCP inp", __func__));
223 
224 	if (inp->inp_flags & INP_DROPPED)
225 		return;
226 
227 	tp = intotcpcb(inp);
228 	if (tp->t_state != TCPS_LISTEN)
229 		return;
230 
231 	t = arg;
232 	mtx_lock(&toedev_lock);
233 	TAILQ_FOREACH(tod, &toedev_list, link) {
234 		if (t == NULL || t == tod)
235 			tod->tod_listen_start(tod, tp);
236 	}
237 	mtx_unlock(&toedev_lock);
238 }
239 
240 static void
241 toe_listen_start_event(void *arg __unused, struct tcpcb *tp)
242 {
243 	struct inpcb *inp = tptoinpcb(tp);
244 
245 	INP_WLOCK_ASSERT(inp);
246 	KASSERT(tp->t_state == TCPS_LISTEN,
247 	    ("%s: t_state %s", __func__, tcpstates[tp->t_state]));
248 
249 	toe_listen_start(inp, NULL);
250 }
251 
252 static void
253 toe_listen_stop_event(void *arg __unused, struct tcpcb *tp)
254 {
255 	struct toedev *tod;
256 #ifdef INVARIANTS
257 	struct inpcb *inp = tptoinpcb(tp);
258 #endif
259 
260 	INP_WLOCK_ASSERT(inp);
261 	KASSERT(tp->t_state == TCPS_LISTEN,
262 	    ("%s: t_state %s", __func__, tcpstates[tp->t_state]));
263 
264 	mtx_lock(&toedev_lock);
265 	TAILQ_FOREACH(tod, &toedev_list, link)
266 	    tod->tod_listen_stop(tod, tp);
267 	mtx_unlock(&toedev_lock);
268 }
269 
270 /*
271  * Fill up a freshly allocated toedev struct with reasonable defaults.
272  */
273 void
274 init_toedev(struct toedev *tod)
275 {
276 
277 	tod->tod_softc = NULL;
278 
279 	/*
280 	 * Provide no-op defaults so that the kernel can call any toedev
281 	 * function without having to check whether the TOE driver supplied one
282 	 * or not.
283 	 */
284 	tod->tod_connect = toedev_connect;
285 	tod->tod_listen_start = toedev_listen_start;
286 	tod->tod_listen_stop = toedev_listen_stop;
287 	tod->tod_input = toedev_input;
288 	tod->tod_rcvd = toedev_rcvd;
289 	tod->tod_output = toedev_output;
290 	tod->tod_send_rst = toedev_output;
291 	tod->tod_send_fin = toedev_output;
292 	tod->tod_pcb_detach = toedev_pcb_detach;
293 	tod->tod_l2_update = toedev_l2_update;
294 	tod->tod_route_redirect = toedev_route_redirect;
295 	tod->tod_syncache_added = toedev_syncache_added;
296 	tod->tod_syncache_removed = toedev_syncache_removed;
297 	tod->tod_syncache_respond = toedev_syncache_respond;
298 	tod->tod_offload_socket = toedev_offload_socket;
299 	tod->tod_ctloutput = toedev_ctloutput;
300 	tod->tod_tcp_info = toedev_tcp_info;
301 	tod->tod_alloc_tls_session = toedev_alloc_tls_session;
302 	tod->tod_pmtu_update = toedev_pmtu_update;
303 }
304 
305 /*
306  * Register an active TOE device with the system.  This allows it to receive
307  * notifications from the kernel.
308  */
309 int
310 register_toedev(struct toedev *tod)
311 {
312 	struct toedev *t;
313 
314 	mtx_lock(&toedev_lock);
315 	TAILQ_FOREACH(t, &toedev_list, link) {
316 		if (t == tod) {
317 			mtx_unlock(&toedev_lock);
318 			return (EEXIST);
319 		}
320 	}
321 
322 	TAILQ_INSERT_TAIL(&toedev_list, tod, link);
323 	registered_toedevs++;
324 	mtx_unlock(&toedev_lock);
325 
326 	inp_apply_all(&V_tcbinfo, toe_listen_start, tod);
327 
328 	return (0);
329 }
330 
331 /*
332  * Remove the TOE device from the global list of active TOE devices.  It is the
333  * caller's responsibility to ensure that the TOE device is quiesced prior to
334  * this call.
335  */
336 int
337 unregister_toedev(struct toedev *tod)
338 {
339 	struct toedev *t, *t2;
340 	int rc = ENODEV;
341 
342 	mtx_lock(&toedev_lock);
343 	TAILQ_FOREACH_SAFE(t, &toedev_list, link, t2) {
344 		if (t == tod) {
345 			TAILQ_REMOVE(&toedev_list, tod, link);
346 			registered_toedevs--;
347 			rc = 0;
348 			break;
349 		}
350 	}
351 	KASSERT(registered_toedevs >= 0,
352 	    ("%s: registered_toedevs (%d) < 0", __func__, registered_toedevs));
353 	mtx_unlock(&toedev_lock);
354 	return (rc);
355 }
356 
357 void
358 toe_syncache_add(struct in_conninfo *inc, struct tcpopt *to, struct tcphdr *th,
359     struct inpcb *inp, void *tod, void *todctx, uint8_t iptos)
360 {
361 
362 	INP_RLOCK_ASSERT(inp);
363 
364 	(void )syncache_add(inc, to, th, inp, inp->inp_socket, NULL, tod,
365 	    todctx, iptos, htons(0));
366 }
367 
368 int
369 toe_syncache_expand(struct in_conninfo *inc, struct tcpopt *to,
370     struct tcphdr *th, struct socket **lsop)
371 {
372 
373 	NET_EPOCH_ASSERT();
374 
375 	return (syncache_expand(inc, to, th, lsop, NULL, htons(0)));
376 }
377 
378 /*
379  * General purpose check to see if a 4-tuple is in use by the kernel.  If a TCP
380  * header (presumably for an incoming SYN) is also provided, an existing 4-tuple
381  * in TIME_WAIT may be assassinated freeing it up for re-use.
382  *
383  * Note that the TCP header must have been run through tcp_fields_to_host() or
384  * equivalent.
385  */
386 int
387 toe_4tuple_check(struct in_conninfo *inc, struct tcphdr *th, struct ifnet *ifp)
388 {
389 	struct inpcb *inp;
390 	struct tcpcb *tp;
391 
392 	if (inc->inc_flags & INC_ISIPV6) {
393 		inp = in6_pcblookup(&V_tcbinfo, &inc->inc6_faddr,
394 		    inc->inc_fport, &inc->inc6_laddr, inc->inc_lport,
395 		    INPLOOKUP_RLOCKPCB, ifp);
396 	} else {
397 		inp = in_pcblookup(&V_tcbinfo, inc->inc_faddr, inc->inc_fport,
398 		    inc->inc_laddr, inc->inc_lport, INPLOOKUP_RLOCKPCB, ifp);
399 	}
400 	if (inp != NULL) {
401 		INP_RLOCK_ASSERT(inp);
402 
403 		tp = intotcpcb(inp);
404 		if (tp->t_state == TCPS_TIME_WAIT && th != NULL) {
405 			if (!tcp_twcheck(inp, NULL, th, NULL, 0))
406 				return (EADDRINUSE);
407 		} else {
408 			INP_RUNLOCK(inp);
409 			return (EADDRINUSE);
410 		}
411 	}
412 
413 	return (0);
414 }
415 
416 static void
417 toe_lle_event(void *arg __unused, struct llentry *lle, int evt)
418 {
419 	struct toedev *tod;
420 	struct ifnet *ifp;
421 	struct sockaddr *sa;
422 	uint8_t *lladdr;
423 	uint16_t vid, pcp;
424 	int family;
425 	struct sockaddr_in6 sin6;
426 
427 	LLE_WLOCK_ASSERT(lle);
428 
429 	ifp = lltable_get_ifp(lle->lle_tbl);
430 	family = lltable_get_af(lle->lle_tbl);
431 
432 	if (family != AF_INET && family != AF_INET6)
433 		return;
434 	/*
435 	 * Not interested if the interface's TOE capability is not enabled.
436 	 */
437 	if ((family == AF_INET && !(ifp->if_capenable & IFCAP_TOE4)) ||
438 	    (family == AF_INET6 && !(ifp->if_capenable & IFCAP_TOE6)))
439 		return;
440 
441 	tod = TOEDEV(ifp);
442 	if (tod == NULL)
443 		return;
444 
445 	sa = (struct sockaddr *)&sin6;
446 	lltable_fill_sa_entry(lle, sa);
447 
448 	vid = 0xfff;
449 	pcp = 0;
450 	if (evt != LLENTRY_RESOLVED) {
451 		/*
452 		 * LLENTRY_TIMEDOUT, LLENTRY_DELETED, LLENTRY_EXPIRED all mean
453 		 * this entry is going to be deleted.
454 		 */
455 
456 		lladdr = NULL;
457 	} else {
458 		KASSERT(lle->la_flags & LLE_VALID,
459 		    ("%s: %p resolved but not valid?", __func__, lle));
460 
461 		lladdr = (uint8_t *)lle->ll_addr;
462 		VLAN_TAG(ifp, &vid);
463 		VLAN_PCP(ifp, &pcp);
464 	}
465 
466 	tod->tod_l2_update(tod, ifp, sa, lladdr, EVL_MAKETAG(vid, pcp, 0));
467 }
468 
469 /*
470  * Returns 0 or EWOULDBLOCK on success (any other value is an error).  0 means
471  * lladdr and vtag are valid on return, EWOULDBLOCK means the TOE driver's
472  * tod_l2_update will be called later, when the entry is resolved or times out.
473  */
474 int
475 toe_l2_resolve(struct toedev *tod, struct ifnet *ifp, struct sockaddr *sa,
476     uint8_t *lladdr, uint16_t *vtag)
477 {
478 	int rc;
479 	uint16_t vid, pcp;
480 
481 	switch (sa->sa_family) {
482 #ifdef INET
483 	case AF_INET:
484 		rc = arpresolve(ifp, 0, NULL, sa, lladdr, NULL, NULL);
485 		break;
486 #endif
487 #ifdef INET6
488 	case AF_INET6:
489 		rc = nd6_resolve(ifp, LLE_SF(AF_INET6, 0), NULL, sa, lladdr,
490 		    NULL, NULL);
491 		break;
492 #endif
493 	default:
494 		return (EPROTONOSUPPORT);
495 	}
496 
497 	if (rc == 0) {
498 		vid = 0xfff;
499 		pcp = 0;
500 		if (ifp->if_type == IFT_L2VLAN) {
501 			VLAN_TAG(ifp, &vid);
502 			VLAN_PCP(ifp, &pcp);
503 		} else if (ifp->if_pcp != IFNET_PCP_NONE) {
504 			vid = 0;
505 			pcp = ifp->if_pcp;
506 		}
507 		*vtag = EVL_MAKETAG(vid, pcp, 0);
508 	}
509 
510 	return (rc);
511 }
512 
513 void
514 toe_connect_failed(struct toedev *tod, struct inpcb *inp, int err)
515 {
516 
517 	NET_EPOCH_ASSERT();
518 	INP_WLOCK_ASSERT(inp);
519 
520 	if (!(inp->inp_flags & INP_DROPPED)) {
521 		struct tcpcb *tp = intotcpcb(inp);
522 
523 		KASSERT(tp->t_flags & TF_TOE,
524 		    ("%s: tp %p not offloaded.", __func__, tp));
525 
526 		if (err == EAGAIN) {
527 			/*
528 			 * Temporary failure during offload, take this PCB back.
529 			 * Detach from the TOE driver and do the rest of what
530 			 * TCP's pru_connect would have done if the connection
531 			 * wasn't offloaded.
532 			 */
533 
534 			tod->tod_pcb_detach(tod, tp);
535 			KASSERT(!(tp->t_flags & TF_TOE),
536 			    ("%s: tp %p still offloaded.", __func__, tp));
537 			tcp_timer_activate(tp, TT_KEEP, TP_KEEPINIT(tp));
538 			if (tcp_output(tp) < 0)
539 				INP_WLOCK(inp);	/* re-acquire */
540 		} else {
541 			tp = tcp_drop(tp, err);
542 			if (tp == NULL)
543 				INP_WLOCK(inp);	/* re-acquire */
544 		}
545 	}
546 	INP_WLOCK_ASSERT(inp);
547 }
548 
549 static int
550 toecore_load(void)
551 {
552 
553 	mtx_init(&toedev_lock, "toedev lock", NULL, MTX_DEF);
554 	TAILQ_INIT(&toedev_list);
555 
556 	listen_start_eh = EVENTHANDLER_REGISTER(tcp_offload_listen_start,
557 	    toe_listen_start_event, NULL, EVENTHANDLER_PRI_ANY);
558 	listen_stop_eh = EVENTHANDLER_REGISTER(tcp_offload_listen_stop,
559 	    toe_listen_stop_event, NULL, EVENTHANDLER_PRI_ANY);
560 	lle_event_eh = EVENTHANDLER_REGISTER(lle_event, toe_lle_event, NULL,
561 	    EVENTHANDLER_PRI_ANY);
562 
563 	return (0);
564 }
565 
566 static int
567 toecore_unload(void)
568 {
569 
570 	mtx_lock(&toedev_lock);
571 	if (!TAILQ_EMPTY(&toedev_list)) {
572 		mtx_unlock(&toedev_lock);
573 		return (EBUSY);
574 	}
575 
576 	EVENTHANDLER_DEREGISTER(tcp_offload_listen_start, listen_start_eh);
577 	EVENTHANDLER_DEREGISTER(tcp_offload_listen_stop, listen_stop_eh);
578 	EVENTHANDLER_DEREGISTER(lle_event, lle_event_eh);
579 
580 	mtx_unlock(&toedev_lock);
581 	mtx_destroy(&toedev_lock);
582 
583 	return (0);
584 }
585 
586 static int
587 toecore_mod_handler(module_t mod, int cmd, void *arg)
588 {
589 
590 	if (cmd == MOD_LOAD)
591 		return (toecore_load());
592 
593 	if (cmd == MOD_UNLOAD)
594 		return (toecore_unload());
595 
596 	return (EOPNOTSUPP);
597 }
598 
599 static moduledata_t mod_data= {
600 	"toecore",
601 	toecore_mod_handler,
602 	0
603 };
604 
605 MODULE_VERSION(toecore, 1);
606 DECLARE_MODULE(toecore, mod_data, SI_SUB_EXEC, SI_ORDER_ANY);
607