xref: /freebsd/sys/netinet/toecore.c (revision 734e82fe33aa764367791a7d603b383996c6b40b)
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 #include "opt_inet.h"
32 #include "opt_inet6.h"
33 
34 #include <sys/param.h>
35 #include <sys/eventhandler.h>
36 #include <sys/kernel.h>
37 #include <sys/systm.h>
38 #include <sys/malloc.h>
39 #include <sys/mbuf.h>
40 #include <sys/module.h>
41 #include <sys/types.h>
42 #include <sys/sockopt.h>
43 #include <sys/sysctl.h>
44 #include <sys/socket.h>
45 
46 #include <net/ethernet.h>
47 #include <net/if.h>
48 #include <net/if_var.h>
49 #include <net/if_private.h>
50 #include <net/if_types.h>
51 #include <net/if_vlan_var.h>
52 #include <net/if_llatbl.h>
53 #include <net/route.h>
54 
55 #include <netinet/if_ether.h>
56 #include <netinet/in.h>
57 #include <netinet/in_pcb.h>
58 #include <netinet/in_var.h>
59 #include <netinet6/in6_var.h>
60 #include <netinet6/in6_pcb.h>
61 #include <netinet6/nd6.h>
62 #define TCPSTATES
63 #include <netinet/tcp.h>
64 #include <netinet/tcp_fsm.h>
65 #include <netinet/tcp_timer.h>
66 #include <netinet/tcp_var.h>
67 #include <netinet/tcp_syncache.h>
68 #include <netinet/tcp_offload.h>
69 #include <netinet/toecore.h>
70 
71 static struct mtx toedev_lock;
72 static TAILQ_HEAD(, toedev) toedev_list;
73 static eventhandler_tag listen_start_eh;
74 static eventhandler_tag listen_stop_eh;
75 static eventhandler_tag lle_event_eh;
76 
77 static int
78 toedev_connect(struct toedev *tod __unused, struct socket *so __unused,
79     struct nhop_object *nh __unused, struct sockaddr *nam __unused)
80 {
81 
82 	return (ENOTSUP);
83 }
84 
85 static int
86 toedev_listen_start(struct toedev *tod __unused, struct tcpcb *tp __unused)
87 {
88 
89 	return (ENOTSUP);
90 }
91 
92 static int
93 toedev_listen_stop(struct toedev *tod __unused, struct tcpcb *tp __unused)
94 {
95 
96 	return (ENOTSUP);
97 }
98 
99 static void
100 toedev_input(struct toedev *tod __unused, struct tcpcb *tp __unused,
101     struct mbuf *m)
102 {
103 
104 	m_freem(m);
105 	return;
106 }
107 
108 static void
109 toedev_rcvd(struct toedev *tod __unused, struct tcpcb *tp __unused)
110 {
111 
112 	return;
113 }
114 
115 static int
116 toedev_output(struct toedev *tod __unused, struct tcpcb *tp __unused)
117 {
118 
119 	return (ENOTSUP);
120 }
121 
122 static void
123 toedev_pcb_detach(struct toedev *tod __unused, struct tcpcb *tp __unused)
124 {
125 
126 	return;
127 }
128 
129 static void
130 toedev_l2_update(struct toedev *tod __unused, struct ifnet *ifp __unused,
131     struct sockaddr *sa __unused, uint8_t *lladdr __unused,
132     uint16_t vtag __unused)
133 {
134 
135 	return;
136 }
137 
138 static void
139 toedev_route_redirect(struct toedev *tod __unused, struct ifnet *ifp __unused,
140     struct nhop_object *nh0 __unused, struct nhop_object *nh1 __unused)
141 {
142 
143 	return;
144 }
145 
146 static void
147 toedev_syncache_added(struct toedev *tod __unused, void *ctx __unused)
148 {
149 
150 	return;
151 }
152 
153 static void
154 toedev_syncache_removed(struct toedev *tod __unused, void *ctx __unused)
155 {
156 
157 	return;
158 }
159 
160 static int
161 toedev_syncache_respond(struct toedev *tod __unused, void *ctx __unused,
162     struct mbuf *m)
163 {
164 
165 	m_freem(m);
166 	return (0);
167 }
168 
169 static void
170 toedev_offload_socket(struct toedev *tod __unused, void *ctx __unused,
171     struct socket *so __unused)
172 {
173 
174 	return;
175 }
176 
177 static void
178 toedev_ctloutput(struct toedev *tod __unused, struct tcpcb *tp __unused,
179     int sopt_dir __unused, int sopt_name __unused)
180 {
181 
182 	return;
183 }
184 
185 static void
186 toedev_tcp_info(struct toedev *tod __unused, struct tcpcb *tp __unused,
187     struct tcp_info *ti __unused)
188 {
189 
190 	return;
191 }
192 
193 static int
194 toedev_alloc_tls_session(struct toedev *tod __unused, struct tcpcb *tp __unused,
195     struct ktls_session *tls __unused, int direction __unused)
196 {
197 
198 	return (EINVAL);
199 }
200 
201 static void
202 toedev_pmtu_update(struct toedev *tod __unused, struct tcpcb *tp __unused,
203     tcp_seq seq __unused, int mtu __unused)
204 {
205 
206 	return;
207 }
208 
209 /*
210  * Inform one or more TOE devices about a listening socket.
211  */
212 static void
213 toe_listen_start(struct inpcb *inp, void *arg)
214 {
215 	struct toedev *t, *tod;
216 	struct tcpcb *tp;
217 
218 	INP_WLOCK_ASSERT(inp);
219 	KASSERT(inp->inp_pcbinfo == &V_tcbinfo,
220 	    ("%s: inp is not a TCP inp", __func__));
221 
222 	if (inp->inp_flags & INP_DROPPED)
223 		return;
224 
225 	tp = intotcpcb(inp);
226 	if (tp->t_state != TCPS_LISTEN)
227 		return;
228 
229 	t = arg;
230 	mtx_lock(&toedev_lock);
231 	TAILQ_FOREACH(tod, &toedev_list, link) {
232 		if (t == NULL || t == tod)
233 			tod->tod_listen_start(tod, tp);
234 	}
235 	mtx_unlock(&toedev_lock);
236 }
237 
238 static void
239 toe_listen_start_event(void *arg __unused, struct tcpcb *tp)
240 {
241 	struct inpcb *inp = tptoinpcb(tp);
242 
243 	INP_WLOCK_ASSERT(inp);
244 	KASSERT(tp->t_state == TCPS_LISTEN,
245 	    ("%s: t_state %s", __func__, tcpstates[tp->t_state]));
246 
247 	toe_listen_start(inp, NULL);
248 }
249 
250 static void
251 toe_listen_stop_event(void *arg __unused, struct tcpcb *tp)
252 {
253 	struct toedev *tod;
254 #ifdef INVARIANTS
255 	struct inpcb *inp = tptoinpcb(tp);
256 #endif
257 
258 	INP_WLOCK_ASSERT(inp);
259 	KASSERT(tp->t_state == TCPS_LISTEN,
260 	    ("%s: t_state %s", __func__, tcpstates[tp->t_state]));
261 
262 	mtx_lock(&toedev_lock);
263 	TAILQ_FOREACH(tod, &toedev_list, link)
264 	    tod->tod_listen_stop(tod, tp);
265 	mtx_unlock(&toedev_lock);
266 }
267 
268 /*
269  * Fill up a freshly allocated toedev struct with reasonable defaults.
270  */
271 void
272 init_toedev(struct toedev *tod)
273 {
274 
275 	tod->tod_softc = NULL;
276 
277 	/*
278 	 * Provide no-op defaults so that the kernel can call any toedev
279 	 * function without having to check whether the TOE driver supplied one
280 	 * or not.
281 	 */
282 	tod->tod_connect = toedev_connect;
283 	tod->tod_listen_start = toedev_listen_start;
284 	tod->tod_listen_stop = toedev_listen_stop;
285 	tod->tod_input = toedev_input;
286 	tod->tod_rcvd = toedev_rcvd;
287 	tod->tod_output = toedev_output;
288 	tod->tod_send_rst = toedev_output;
289 	tod->tod_send_fin = toedev_output;
290 	tod->tod_pcb_detach = toedev_pcb_detach;
291 	tod->tod_l2_update = toedev_l2_update;
292 	tod->tod_route_redirect = toedev_route_redirect;
293 	tod->tod_syncache_added = toedev_syncache_added;
294 	tod->tod_syncache_removed = toedev_syncache_removed;
295 	tod->tod_syncache_respond = toedev_syncache_respond;
296 	tod->tod_offload_socket = toedev_offload_socket;
297 	tod->tod_ctloutput = toedev_ctloutput;
298 	tod->tod_tcp_info = toedev_tcp_info;
299 	tod->tod_alloc_tls_session = toedev_alloc_tls_session;
300 	tod->tod_pmtu_update = toedev_pmtu_update;
301 }
302 
303 /*
304  * Register an active TOE device with the system.  This allows it to receive
305  * notifications from the kernel.
306  */
307 int
308 register_toedev(struct toedev *tod)
309 {
310 	struct toedev *t;
311 
312 	mtx_lock(&toedev_lock);
313 	TAILQ_FOREACH(t, &toedev_list, link) {
314 		if (t == tod) {
315 			mtx_unlock(&toedev_lock);
316 			return (EEXIST);
317 		}
318 	}
319 
320 	TAILQ_INSERT_TAIL(&toedev_list, tod, link);
321 	registered_toedevs++;
322 	mtx_unlock(&toedev_lock);
323 
324 	inp_apply_all(&V_tcbinfo, toe_listen_start, tod);
325 
326 	return (0);
327 }
328 
329 /*
330  * Remove the TOE device from the global list of active TOE devices.  It is the
331  * caller's responsibility to ensure that the TOE device is quiesced prior to
332  * this call.
333  */
334 int
335 unregister_toedev(struct toedev *tod)
336 {
337 	struct toedev *t, *t2;
338 	int rc = ENODEV;
339 
340 	mtx_lock(&toedev_lock);
341 	TAILQ_FOREACH_SAFE(t, &toedev_list, link, t2) {
342 		if (t == tod) {
343 			TAILQ_REMOVE(&toedev_list, tod, link);
344 			registered_toedevs--;
345 			rc = 0;
346 			break;
347 		}
348 	}
349 	KASSERT(registered_toedevs >= 0,
350 	    ("%s: registered_toedevs (%d) < 0", __func__, registered_toedevs));
351 	mtx_unlock(&toedev_lock);
352 	return (rc);
353 }
354 
355 void
356 toe_syncache_add(struct in_conninfo *inc, struct tcpopt *to, struct tcphdr *th,
357     struct inpcb *inp, void *tod, void *todctx, uint8_t iptos)
358 {
359 
360 	INP_RLOCK_ASSERT(inp);
361 
362 	(void )syncache_add(inc, to, th, inp, inp->inp_socket, NULL, tod,
363 	    todctx, iptos, htons(0));
364 }
365 
366 int
367 toe_syncache_expand(struct in_conninfo *inc, struct tcpopt *to,
368     struct tcphdr *th, struct socket **lsop)
369 {
370 
371 	NET_EPOCH_ASSERT();
372 
373 	return (syncache_expand(inc, to, th, lsop, NULL, htons(0)));
374 }
375 
376 /*
377  * General purpose check to see if a 4-tuple is in use by the kernel.  If a TCP
378  * header (presumably for an incoming SYN) is also provided, an existing 4-tuple
379  * in TIME_WAIT may be assassinated freeing it up for re-use.
380  *
381  * Note that the TCP header must have been run through tcp_fields_to_host() or
382  * equivalent.
383  */
384 int
385 toe_4tuple_check(struct in_conninfo *inc, struct tcphdr *th, struct ifnet *ifp)
386 {
387 	struct inpcb *inp;
388 	struct tcpcb *tp;
389 
390 	if (inc->inc_flags & INC_ISIPV6) {
391 		inp = in6_pcblookup(&V_tcbinfo, &inc->inc6_faddr,
392 		    inc->inc_fport, &inc->inc6_laddr, inc->inc_lport,
393 		    INPLOOKUP_RLOCKPCB, ifp);
394 	} else {
395 		inp = in_pcblookup(&V_tcbinfo, inc->inc_faddr, inc->inc_fport,
396 		    inc->inc_laddr, inc->inc_lport, INPLOOKUP_RLOCKPCB, ifp);
397 	}
398 	if (inp != NULL) {
399 		INP_RLOCK_ASSERT(inp);
400 
401 		tp = intotcpcb(inp);
402 		if (tp->t_state == TCPS_TIME_WAIT && th != NULL) {
403 			if (!tcp_twcheck(inp, NULL, th, NULL, 0))
404 				return (EADDRINUSE);
405 		} else {
406 			INP_RUNLOCK(inp);
407 			return (EADDRINUSE);
408 		}
409 	}
410 
411 	return (0);
412 }
413 
414 static void
415 toe_lle_event(void *arg __unused, struct llentry *lle, int evt)
416 {
417 	struct toedev *tod;
418 	struct ifnet *ifp;
419 	struct sockaddr *sa;
420 	uint8_t *lladdr;
421 	uint16_t vid, pcp;
422 	int family;
423 	struct sockaddr_in6 sin6;
424 
425 	LLE_WLOCK_ASSERT(lle);
426 
427 	ifp = lltable_get_ifp(lle->lle_tbl);
428 	family = lltable_get_af(lle->lle_tbl);
429 
430 	if (family != AF_INET && family != AF_INET6)
431 		return;
432 	/*
433 	 * Not interested if the interface's TOE capability is not enabled.
434 	 */
435 	if ((family == AF_INET && !(ifp->if_capenable & IFCAP_TOE4)) ||
436 	    (family == AF_INET6 && !(ifp->if_capenable & IFCAP_TOE6)))
437 		return;
438 
439 	tod = TOEDEV(ifp);
440 	if (tod == NULL)
441 		return;
442 
443 	sa = (struct sockaddr *)&sin6;
444 	lltable_fill_sa_entry(lle, sa);
445 
446 	vid = 0xfff;
447 	pcp = 0;
448 	if (evt != LLENTRY_RESOLVED) {
449 		/*
450 		 * LLENTRY_TIMEDOUT, LLENTRY_DELETED, LLENTRY_EXPIRED all mean
451 		 * this entry is going to be deleted.
452 		 */
453 
454 		lladdr = NULL;
455 	} else {
456 		KASSERT(lle->la_flags & LLE_VALID,
457 		    ("%s: %p resolved but not valid?", __func__, lle));
458 
459 		lladdr = (uint8_t *)lle->ll_addr;
460 		VLAN_TAG(ifp, &vid);
461 		VLAN_PCP(ifp, &pcp);
462 	}
463 
464 	tod->tod_l2_update(tod, ifp, sa, lladdr, EVL_MAKETAG(vid, pcp, 0));
465 }
466 
467 /*
468  * Returns 0 or EWOULDBLOCK on success (any other value is an error).  0 means
469  * lladdr and vtag are valid on return, EWOULDBLOCK means the TOE driver's
470  * tod_l2_update will be called later, when the entry is resolved or times out.
471  */
472 int
473 toe_l2_resolve(struct toedev *tod, struct ifnet *ifp, struct sockaddr *sa,
474     uint8_t *lladdr, uint16_t *vtag)
475 {
476 	int rc;
477 	uint16_t vid, pcp;
478 
479 	switch (sa->sa_family) {
480 #ifdef INET
481 	case AF_INET:
482 		rc = arpresolve(ifp, 0, NULL, sa, lladdr, NULL, NULL);
483 		break;
484 #endif
485 #ifdef INET6
486 	case AF_INET6:
487 		rc = nd6_resolve(ifp, LLE_SF(AF_INET6, 0), NULL, sa, lladdr,
488 		    NULL, NULL);
489 		break;
490 #endif
491 	default:
492 		return (EPROTONOSUPPORT);
493 	}
494 
495 	if (rc == 0) {
496 		vid = 0xfff;
497 		pcp = 0;
498 		if (ifp->if_type == IFT_L2VLAN) {
499 			VLAN_TAG(ifp, &vid);
500 			VLAN_PCP(ifp, &pcp);
501 		} else if (ifp->if_pcp != IFNET_PCP_NONE) {
502 			vid = 0;
503 			pcp = ifp->if_pcp;
504 		}
505 		*vtag = EVL_MAKETAG(vid, pcp, 0);
506 	}
507 
508 	return (rc);
509 }
510 
511 void
512 toe_connect_failed(struct toedev *tod, struct inpcb *inp, int err)
513 {
514 
515 	NET_EPOCH_ASSERT();
516 	INP_WLOCK_ASSERT(inp);
517 
518 	if (!(inp->inp_flags & INP_DROPPED)) {
519 		struct tcpcb *tp = intotcpcb(inp);
520 
521 		KASSERT(tp->t_flags & TF_TOE,
522 		    ("%s: tp %p not offloaded.", __func__, tp));
523 
524 		if (err == EAGAIN) {
525 			/*
526 			 * Temporary failure during offload, take this PCB back.
527 			 * Detach from the TOE driver and do the rest of what
528 			 * TCP's pru_connect would have done if the connection
529 			 * wasn't offloaded.
530 			 */
531 
532 			tod->tod_pcb_detach(tod, tp);
533 			KASSERT(!(tp->t_flags & TF_TOE),
534 			    ("%s: tp %p still offloaded.", __func__, tp));
535 			tcp_timer_activate(tp, TT_KEEP, TP_KEEPINIT(tp));
536 			if (tcp_output(tp) < 0)
537 				INP_WLOCK(inp);	/* re-acquire */
538 		} else {
539 			tp = tcp_drop(tp, err);
540 			if (tp == NULL)
541 				INP_WLOCK(inp);	/* re-acquire */
542 		}
543 	}
544 	INP_WLOCK_ASSERT(inp);
545 }
546 
547 static int
548 toecore_load(void)
549 {
550 
551 	mtx_init(&toedev_lock, "toedev lock", NULL, MTX_DEF);
552 	TAILQ_INIT(&toedev_list);
553 
554 	listen_start_eh = EVENTHANDLER_REGISTER(tcp_offload_listen_start,
555 	    toe_listen_start_event, NULL, EVENTHANDLER_PRI_ANY);
556 	listen_stop_eh = EVENTHANDLER_REGISTER(tcp_offload_listen_stop,
557 	    toe_listen_stop_event, NULL, EVENTHANDLER_PRI_ANY);
558 	lle_event_eh = EVENTHANDLER_REGISTER(lle_event, toe_lle_event, NULL,
559 	    EVENTHANDLER_PRI_ANY);
560 
561 	return (0);
562 }
563 
564 static int
565 toecore_unload(void)
566 {
567 
568 	mtx_lock(&toedev_lock);
569 	if (!TAILQ_EMPTY(&toedev_list)) {
570 		mtx_unlock(&toedev_lock);
571 		return (EBUSY);
572 	}
573 
574 	EVENTHANDLER_DEREGISTER(tcp_offload_listen_start, listen_start_eh);
575 	EVENTHANDLER_DEREGISTER(tcp_offload_listen_stop, listen_stop_eh);
576 	EVENTHANDLER_DEREGISTER(lle_event, lle_event_eh);
577 
578 	mtx_unlock(&toedev_lock);
579 	mtx_destroy(&toedev_lock);
580 
581 	return (0);
582 }
583 
584 static int
585 toecore_mod_handler(module_t mod, int cmd, void *arg)
586 {
587 
588 	if (cmd == MOD_LOAD)
589 		return (toecore_load());
590 
591 	if (cmd == MOD_UNLOAD)
592 		return (toecore_unload());
593 
594 	return (EOPNOTSUPP);
595 }
596 
597 static moduledata_t mod_data= {
598 	"toecore",
599 	toecore_mod_handler,
600 	0
601 };
602 
603 MODULE_VERSION(toecore, 1);
604 DECLARE_MODULE(toecore, mod_data, SI_SUB_EXEC, SI_ORDER_ANY);
605