xref: /freebsd/sys/netinet/toecore.c (revision 5bb3134a8c21cb87b30e135ef168483f0333dabb)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
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_types.h>
52 #include <net/if_vlan_var.h>
53 #include <net/if_llatbl.h>
54 #include <net/route.h>
55 
56 #include <netinet/if_ether.h>
57 #include <netinet/in.h>
58 #include <netinet/in_pcb.h>
59 #include <netinet/in_var.h>
60 #include <netinet6/in6_var.h>
61 #include <netinet6/in6_pcb.h>
62 #include <netinet6/nd6.h>
63 #define TCPSTATES
64 #include <netinet/tcp.h>
65 #include <netinet/tcp_fsm.h>
66 #include <netinet/tcp_timer.h>
67 #include <netinet/tcp_var.h>
68 #include <netinet/tcp_syncache.h>
69 #include <netinet/tcp_offload.h>
70 #include <netinet/toecore.h>
71 
72 static struct mtx toedev_lock;
73 static TAILQ_HEAD(, toedev) toedev_list;
74 static eventhandler_tag listen_start_eh;
75 static eventhandler_tag listen_stop_eh;
76 static eventhandler_tag lle_event_eh;
77 
78 static int
79 toedev_connect(struct toedev *tod __unused, struct socket *so __unused,
80     struct nhop_object *nh __unused, struct sockaddr *nam __unused)
81 {
82 
83 	return (ENOTSUP);
84 }
85 
86 static int
87 toedev_listen_start(struct toedev *tod __unused, struct tcpcb *tp __unused)
88 {
89 
90 	return (ENOTSUP);
91 }
92 
93 static int
94 toedev_listen_stop(struct toedev *tod __unused, struct tcpcb *tp __unused)
95 {
96 
97 	return (ENOTSUP);
98 }
99 
100 static void
101 toedev_input(struct toedev *tod __unused, struct tcpcb *tp __unused,
102     struct mbuf *m)
103 {
104 
105 	m_freem(m);
106 	return;
107 }
108 
109 static void
110 toedev_rcvd(struct toedev *tod __unused, struct tcpcb *tp __unused)
111 {
112 
113 	return;
114 }
115 
116 static int
117 toedev_output(struct toedev *tod __unused, struct tcpcb *tp __unused)
118 {
119 
120 	return (ENOTSUP);
121 }
122 
123 static void
124 toedev_pcb_detach(struct toedev *tod __unused, struct tcpcb *tp __unused)
125 {
126 
127 	return;
128 }
129 
130 static void
131 toedev_l2_update(struct toedev *tod __unused, struct ifnet *ifp __unused,
132     struct sockaddr *sa __unused, uint8_t *lladdr __unused,
133     uint16_t vtag __unused)
134 {
135 
136 	return;
137 }
138 
139 static void
140 toedev_route_redirect(struct toedev *tod __unused, struct ifnet *ifp __unused,
141     struct nhop_object *nh0 __unused, struct nhop_object *nh1 __unused)
142 {
143 
144 	return;
145 }
146 
147 static void
148 toedev_syncache_added(struct toedev *tod __unused, void *ctx __unused)
149 {
150 
151 	return;
152 }
153 
154 static void
155 toedev_syncache_removed(struct toedev *tod __unused, void *ctx __unused)
156 {
157 
158 	return;
159 }
160 
161 static int
162 toedev_syncache_respond(struct toedev *tod __unused, void *ctx __unused,
163     struct mbuf *m)
164 {
165 
166 	m_freem(m);
167 	return (0);
168 }
169 
170 static void
171 toedev_offload_socket(struct toedev *tod __unused, void *ctx __unused,
172     struct socket *so __unused)
173 {
174 
175 	return;
176 }
177 
178 static void
179 toedev_ctloutput(struct toedev *tod __unused, struct tcpcb *tp __unused,
180     int sopt_dir __unused, int sopt_name __unused)
181 {
182 
183 	return;
184 }
185 
186 static void
187 toedev_tcp_info(struct toedev *tod __unused, struct tcpcb *tp __unused,
188     struct tcp_info *ti __unused)
189 {
190 
191 	return;
192 }
193 
194 static int
195 toedev_alloc_tls_session(struct toedev *tod __unused, struct tcpcb *tp __unused,
196     struct ktls_session *tls __unused, int direction __unused)
197 {
198 
199 	return (EINVAL);
200 }
201 
202 static void
203 toedev_pmtu_update(struct toedev *tod __unused, struct tcpcb *tp __unused,
204     tcp_seq seq __unused, int mtu __unused)
205 {
206 
207 	return;
208 }
209 
210 /*
211  * Inform one or more TOE devices about a listening socket.
212  */
213 static void
214 toe_listen_start(struct inpcb *inp, void *arg)
215 {
216 	struct toedev *t, *tod;
217 	struct tcpcb *tp;
218 
219 	INP_WLOCK_ASSERT(inp);
220 	KASSERT(inp->inp_pcbinfo == &V_tcbinfo,
221 	    ("%s: inp is not a TCP inp", __func__));
222 
223 	if (inp->inp_flags & (INP_DROPPED | INP_TIMEWAIT))
224 		return;
225 
226 	tp = intotcpcb(inp);
227 	if (tp->t_state != TCPS_LISTEN)
228 		return;
229 
230 	t = arg;
231 	mtx_lock(&toedev_lock);
232 	TAILQ_FOREACH(tod, &toedev_list, link) {
233 		if (t == NULL || t == tod)
234 			tod->tod_listen_start(tod, tp);
235 	}
236 	mtx_unlock(&toedev_lock);
237 }
238 
239 static void
240 toe_listen_start_event(void *arg __unused, struct tcpcb *tp)
241 {
242 	struct inpcb *inp = tp->t_inpcb;
243 
244 	INP_WLOCK_ASSERT(inp);
245 	KASSERT(tp->t_state == TCPS_LISTEN,
246 	    ("%s: t_state %s", __func__, tcpstates[tp->t_state]));
247 
248 	toe_listen_start(inp, NULL);
249 }
250 
251 static void
252 toe_listen_stop_event(void *arg __unused, struct tcpcb *tp)
253 {
254 	struct toedev *tod;
255 #ifdef INVARIANTS
256 	struct inpcb *inp = tp->t_inpcb;
257 #endif
258 
259 	INP_WLOCK_ASSERT(inp);
260 	KASSERT(tp->t_state == TCPS_LISTEN,
261 	    ("%s: t_state %s", __func__, tcpstates[tp->t_state]));
262 
263 	mtx_lock(&toedev_lock);
264 	TAILQ_FOREACH(tod, &toedev_list, link)
265 	    tod->tod_listen_stop(tod, tp);
266 	mtx_unlock(&toedev_lock);
267 }
268 
269 /*
270  * Fill up a freshly allocated toedev struct with reasonable defaults.
271  */
272 void
273 init_toedev(struct toedev *tod)
274 {
275 
276 	tod->tod_softc = NULL;
277 
278 	/*
279 	 * Provide no-op defaults so that the kernel can call any toedev
280 	 * function without having to check whether the TOE driver supplied one
281 	 * or not.
282 	 */
283 	tod->tod_connect = toedev_connect;
284 	tod->tod_listen_start = toedev_listen_start;
285 	tod->tod_listen_stop = toedev_listen_stop;
286 	tod->tod_input = toedev_input;
287 	tod->tod_rcvd = toedev_rcvd;
288 	tod->tod_output = toedev_output;
289 	tod->tod_send_rst = toedev_output;
290 	tod->tod_send_fin = toedev_output;
291 	tod->tod_pcb_detach = toedev_pcb_detach;
292 	tod->tod_l2_update = toedev_l2_update;
293 	tod->tod_route_redirect = toedev_route_redirect;
294 	tod->tod_syncache_added = toedev_syncache_added;
295 	tod->tod_syncache_removed = toedev_syncache_removed;
296 	tod->tod_syncache_respond = toedev_syncache_respond;
297 	tod->tod_offload_socket = toedev_offload_socket;
298 	tod->tod_ctloutput = toedev_ctloutput;
299 	tod->tod_tcp_info = toedev_tcp_info;
300 	tod->tod_alloc_tls_session = toedev_alloc_tls_session;
301 	tod->tod_pmtu_update = toedev_pmtu_update;
302 }
303 
304 /*
305  * Register an active TOE device with the system.  This allows it to receive
306  * notifications from the kernel.
307  */
308 int
309 register_toedev(struct toedev *tod)
310 {
311 	struct toedev *t;
312 
313 	mtx_lock(&toedev_lock);
314 	TAILQ_FOREACH(t, &toedev_list, link) {
315 		if (t == tod) {
316 			mtx_unlock(&toedev_lock);
317 			return (EEXIST);
318 		}
319 	}
320 
321 	TAILQ_INSERT_TAIL(&toedev_list, tod, link);
322 	registered_toedevs++;
323 	mtx_unlock(&toedev_lock);
324 
325 	inp_apply_all(toe_listen_start, tod);
326 
327 	return (0);
328 }
329 
330 /*
331  * Remove the TOE device from the global list of active TOE devices.  It is the
332  * caller's responsibility to ensure that the TOE device is quiesced prior to
333  * this call.
334  */
335 int
336 unregister_toedev(struct toedev *tod)
337 {
338 	struct toedev *t, *t2;
339 	int rc = ENODEV;
340 
341 	mtx_lock(&toedev_lock);
342 	TAILQ_FOREACH_SAFE(t, &toedev_list, link, t2) {
343 		if (t == tod) {
344 			TAILQ_REMOVE(&toedev_list, tod, link);
345 			registered_toedevs--;
346 			rc = 0;
347 			break;
348 		}
349 	}
350 	KASSERT(registered_toedevs >= 0,
351 	    ("%s: registered_toedevs (%d) < 0", __func__, registered_toedevs));
352 	mtx_unlock(&toedev_lock);
353 	return (rc);
354 }
355 
356 void
357 toe_syncache_add(struct in_conninfo *inc, struct tcpopt *to, struct tcphdr *th,
358     struct inpcb *inp, void *tod, void *todctx, uint8_t iptos)
359 {
360 
361 	INP_RLOCK_ASSERT(inp);
362 
363 	(void )syncache_add(inc, to, th, inp, inp->inp_socket, NULL, tod,
364 	    todctx, iptos, htons(0));
365 }
366 
367 int
368 toe_syncache_expand(struct in_conninfo *inc, struct tcpopt *to,
369     struct tcphdr *th, struct socket **lsop)
370 {
371 
372 	NET_EPOCH_ASSERT();
373 
374 	return (syncache_expand(inc, to, th, lsop, NULL, htons(0)));
375 }
376 
377 /*
378  * General purpose check to see if a 4-tuple is in use by the kernel.  If a TCP
379  * header (presumably for an incoming SYN) is also provided, an existing 4-tuple
380  * in TIME_WAIT may be assassinated freeing it up for re-use.
381  *
382  * Note that the TCP header must have been run through tcp_fields_to_host() or
383  * equivalent.
384  */
385 int
386 toe_4tuple_check(struct in_conninfo *inc, struct tcphdr *th, struct ifnet *ifp)
387 {
388 	struct inpcb *inp;
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 		if ((inp->inp_flags & INP_TIMEWAIT) && th != NULL) {
402 			if (!tcp_twcheck(inp, NULL, th, NULL, 0))
403 				return (EADDRINUSE);
404 		} else {
405 			INP_RUNLOCK(inp);
406 			return (EADDRINUSE);
407 		}
408 	}
409 
410 	return (0);
411 }
412 
413 static void
414 toe_lle_event(void *arg __unused, struct llentry *lle, int evt)
415 {
416 	struct toedev *tod;
417 	struct ifnet *ifp;
418 	struct sockaddr *sa;
419 	uint8_t *lladdr;
420 	uint16_t vid, pcp;
421 	int family;
422 	struct sockaddr_in6 sin6;
423 
424 	LLE_WLOCK_ASSERT(lle);
425 
426 	ifp = lltable_get_ifp(lle->lle_tbl);
427 	family = lltable_get_af(lle->lle_tbl);
428 
429 	if (family != AF_INET && family != AF_INET6)
430 		return;
431 	/*
432 	 * Not interested if the interface's TOE capability is not enabled.
433 	 */
434 	if ((family == AF_INET && !(ifp->if_capenable & IFCAP_TOE4)) ||
435 	    (family == AF_INET6 && !(ifp->if_capenable & IFCAP_TOE6)))
436 		return;
437 
438 	tod = TOEDEV(ifp);
439 	if (tod == NULL)
440 		return;
441 
442 	sa = (struct sockaddr *)&sin6;
443 	lltable_fill_sa_entry(lle, sa);
444 
445 	vid = 0xfff;
446 	pcp = 0;
447 	if (evt != LLENTRY_RESOLVED) {
448 		/*
449 		 * LLENTRY_TIMEDOUT, LLENTRY_DELETED, LLENTRY_EXPIRED all mean
450 		 * this entry is going to be deleted.
451 		 */
452 
453 		lladdr = NULL;
454 	} else {
455 		KASSERT(lle->la_flags & LLE_VALID,
456 		    ("%s: %p resolved but not valid?", __func__, lle));
457 
458 		lladdr = (uint8_t *)lle->ll_addr;
459 		VLAN_TAG(ifp, &vid);
460 		VLAN_PCP(ifp, &pcp);
461 	}
462 
463 	tod->tod_l2_update(tod, ifp, sa, lladdr, EVL_MAKETAG(vid, pcp, 0));
464 }
465 
466 /*
467  * Returns 0 or EWOULDBLOCK on success (any other value is an error).  0 means
468  * lladdr and vtag are valid on return, EWOULDBLOCK means the TOE driver's
469  * tod_l2_update will be called later, when the entry is resolved or times out.
470  */
471 int
472 toe_l2_resolve(struct toedev *tod, struct ifnet *ifp, struct sockaddr *sa,
473     uint8_t *lladdr, uint16_t *vtag)
474 {
475 	int rc;
476 	uint16_t vid, pcp;
477 
478 	switch (sa->sa_family) {
479 #ifdef INET
480 	case AF_INET:
481 		rc = arpresolve(ifp, 0, NULL, sa, lladdr, NULL, NULL);
482 		break;
483 #endif
484 #ifdef INET6
485 	case AF_INET6:
486 		rc = nd6_resolve(ifp, LLE_SF(AF_INET6, 0), NULL, sa, lladdr,
487 		    NULL, NULL);
488 		break;
489 #endif
490 	default:
491 		return (EPROTONOSUPPORT);
492 	}
493 
494 	if (rc == 0) {
495 		vid = 0xfff;
496 		pcp = 0;
497 		if (ifp->if_type == IFT_L2VLAN) {
498 			VLAN_TAG(ifp, &vid);
499 			VLAN_PCP(ifp, &pcp);
500 		} else if (ifp->if_pcp != IFNET_PCP_NONE) {
501 			vid = 0;
502 			pcp = ifp->if_pcp;
503 		}
504 		*vtag = EVL_MAKETAG(vid, pcp, 0);
505 	}
506 
507 	return (rc);
508 }
509 
510 void
511 toe_connect_failed(struct toedev *tod, struct inpcb *inp, int err)
512 {
513 
514 	NET_EPOCH_ASSERT();
515 	INP_WLOCK_ASSERT(inp);
516 
517 	if (!(inp->inp_flags & INP_DROPPED)) {
518 		struct tcpcb *tp = intotcpcb(inp);
519 
520 		KASSERT(tp->t_flags & TF_TOE,
521 		    ("%s: tp %p not offloaded.", __func__, tp));
522 
523 		if (err == EAGAIN) {
524 			/*
525 			 * Temporary failure during offload, take this PCB back.
526 			 * Detach from the TOE driver and do the rest of what
527 			 * TCP's pru_connect would have done if the connection
528 			 * wasn't offloaded.
529 			 */
530 
531 			tod->tod_pcb_detach(tod, tp);
532 			KASSERT(!(tp->t_flags & TF_TOE),
533 			    ("%s: tp %p still offloaded.", __func__, tp));
534 			tcp_timer_activate(tp, TT_KEEP, TP_KEEPINIT(tp));
535 			(void) tp->t_fb->tfb_tcp_output(tp);
536 		} else {
537 			tp = tcp_drop(tp, err);
538 			if (tp == NULL)
539 				INP_WLOCK(inp);	/* re-acquire */
540 		}
541 	}
542 	INP_WLOCK_ASSERT(inp);
543 }
544 
545 static int
546 toecore_load(void)
547 {
548 
549 	mtx_init(&toedev_lock, "toedev lock", NULL, MTX_DEF);
550 	TAILQ_INIT(&toedev_list);
551 
552 	listen_start_eh = EVENTHANDLER_REGISTER(tcp_offload_listen_start,
553 	    toe_listen_start_event, NULL, EVENTHANDLER_PRI_ANY);
554 	listen_stop_eh = EVENTHANDLER_REGISTER(tcp_offload_listen_stop,
555 	    toe_listen_stop_event, NULL, EVENTHANDLER_PRI_ANY);
556 	lle_event_eh = EVENTHANDLER_REGISTER(lle_event, toe_lle_event, NULL,
557 	    EVENTHANDLER_PRI_ANY);
558 
559 	return (0);
560 }
561 
562 static int
563 toecore_unload(void)
564 {
565 
566 	mtx_lock(&toedev_lock);
567 	if (!TAILQ_EMPTY(&toedev_list)) {
568 		mtx_unlock(&toedev_lock);
569 		return (EBUSY);
570 	}
571 
572 	EVENTHANDLER_DEREGISTER(tcp_offload_listen_start, listen_start_eh);
573 	EVENTHANDLER_DEREGISTER(tcp_offload_listen_stop, listen_stop_eh);
574 	EVENTHANDLER_DEREGISTER(lle_event, lle_event_eh);
575 
576 	mtx_unlock(&toedev_lock);
577 	mtx_destroy(&toedev_lock);
578 
579 	return (0);
580 }
581 
582 static int
583 toecore_mod_handler(module_t mod, int cmd, void *arg)
584 {
585 
586 	if (cmd == MOD_LOAD)
587 		return (toecore_load());
588 
589 	if (cmd == MOD_UNLOAD)
590 		return (toecore_unload());
591 
592 	return (EOPNOTSUPP);
593 }
594 
595 static moduledata_t mod_data= {
596 	"toecore",
597 	toecore_mod_handler,
598 	0
599 };
600 
601 MODULE_VERSION(toecore, 1);
602 DECLARE_MODULE(toecore, mod_data, SI_SUB_EXEC, SI_ORDER_ANY);
603