xref: /freebsd/sys/netinet/toecore.c (revision c66ec88fed842fbaad62c30d510644ceb7bd2d71)
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 /*
203  * Inform one or more TOE devices about a listening socket.
204  */
205 static void
206 toe_listen_start(struct inpcb *inp, void *arg)
207 {
208 	struct toedev *t, *tod;
209 	struct tcpcb *tp;
210 
211 	INP_WLOCK_ASSERT(inp);
212 	KASSERT(inp->inp_pcbinfo == &V_tcbinfo,
213 	    ("%s: inp is not a TCP inp", __func__));
214 
215 	if (inp->inp_flags & (INP_DROPPED | INP_TIMEWAIT))
216 		return;
217 
218 	tp = intotcpcb(inp);
219 	if (tp->t_state != TCPS_LISTEN)
220 		return;
221 
222 	t = arg;
223 	mtx_lock(&toedev_lock);
224 	TAILQ_FOREACH(tod, &toedev_list, link) {
225 		if (t == NULL || t == tod)
226 			tod->tod_listen_start(tod, tp);
227 	}
228 	mtx_unlock(&toedev_lock);
229 }
230 
231 static void
232 toe_listen_start_event(void *arg __unused, struct tcpcb *tp)
233 {
234 	struct inpcb *inp = tp->t_inpcb;
235 
236 	INP_WLOCK_ASSERT(inp);
237 	KASSERT(tp->t_state == TCPS_LISTEN,
238 	    ("%s: t_state %s", __func__, tcpstates[tp->t_state]));
239 
240 	toe_listen_start(inp, NULL);
241 }
242 
243 static void
244 toe_listen_stop_event(void *arg __unused, struct tcpcb *tp)
245 {
246 	struct toedev *tod;
247 #ifdef INVARIANTS
248 	struct inpcb *inp = tp->t_inpcb;
249 #endif
250 
251 	INP_WLOCK_ASSERT(inp);
252 	KASSERT(tp->t_state == TCPS_LISTEN,
253 	    ("%s: t_state %s", __func__, tcpstates[tp->t_state]));
254 
255 	mtx_lock(&toedev_lock);
256 	TAILQ_FOREACH(tod, &toedev_list, link)
257 	    tod->tod_listen_stop(tod, tp);
258 	mtx_unlock(&toedev_lock);
259 }
260 
261 /*
262  * Fill up a freshly allocated toedev struct with reasonable defaults.
263  */
264 void
265 init_toedev(struct toedev *tod)
266 {
267 
268 	tod->tod_softc = NULL;
269 
270 	/*
271 	 * Provide no-op defaults so that the kernel can call any toedev
272 	 * function without having to check whether the TOE driver supplied one
273 	 * or not.
274 	 */
275 	tod->tod_connect = toedev_connect;
276 	tod->tod_listen_start = toedev_listen_start;
277 	tod->tod_listen_stop = toedev_listen_stop;
278 	tod->tod_input = toedev_input;
279 	tod->tod_rcvd = toedev_rcvd;
280 	tod->tod_output = toedev_output;
281 	tod->tod_send_rst = toedev_output;
282 	tod->tod_send_fin = toedev_output;
283 	tod->tod_pcb_detach = toedev_pcb_detach;
284 	tod->tod_l2_update = toedev_l2_update;
285 	tod->tod_route_redirect = toedev_route_redirect;
286 	tod->tod_syncache_added = toedev_syncache_added;
287 	tod->tod_syncache_removed = toedev_syncache_removed;
288 	tod->tod_syncache_respond = toedev_syncache_respond;
289 	tod->tod_offload_socket = toedev_offload_socket;
290 	tod->tod_ctloutput = toedev_ctloutput;
291 	tod->tod_tcp_info = toedev_tcp_info;
292 	tod->tod_alloc_tls_session = toedev_alloc_tls_session;
293 }
294 
295 /*
296  * Register an active TOE device with the system.  This allows it to receive
297  * notifications from the kernel.
298  */
299 int
300 register_toedev(struct toedev *tod)
301 {
302 	struct toedev *t;
303 
304 	mtx_lock(&toedev_lock);
305 	TAILQ_FOREACH(t, &toedev_list, link) {
306 		if (t == tod) {
307 			mtx_unlock(&toedev_lock);
308 			return (EEXIST);
309 		}
310 	}
311 
312 	TAILQ_INSERT_TAIL(&toedev_list, tod, link);
313 	registered_toedevs++;
314 	mtx_unlock(&toedev_lock);
315 
316 	inp_apply_all(toe_listen_start, tod);
317 
318 	return (0);
319 }
320 
321 /*
322  * Remove the TOE device from the global list of active TOE devices.  It is the
323  * caller's responsibility to ensure that the TOE device is quiesced prior to
324  * this call.
325  */
326 int
327 unregister_toedev(struct toedev *tod)
328 {
329 	struct toedev *t, *t2;
330 	int rc = ENODEV;
331 
332 	mtx_lock(&toedev_lock);
333 	TAILQ_FOREACH_SAFE(t, &toedev_list, link, t2) {
334 		if (t == tod) {
335 			TAILQ_REMOVE(&toedev_list, tod, link);
336 			registered_toedevs--;
337 			rc = 0;
338 			break;
339 		}
340 	}
341 	KASSERT(registered_toedevs >= 0,
342 	    ("%s: registered_toedevs (%d) < 0", __func__, registered_toedevs));
343 	mtx_unlock(&toedev_lock);
344 	return (rc);
345 }
346 
347 void
348 toe_syncache_add(struct in_conninfo *inc, struct tcpopt *to, struct tcphdr *th,
349     struct inpcb *inp, void *tod, void *todctx, uint8_t iptos)
350 {
351 	struct socket *lso = inp->inp_socket;
352 
353 	INP_WLOCK_ASSERT(inp);
354 
355 	syncache_add(inc, to, th, inp, &lso, NULL, tod, todctx, iptos);
356 }
357 
358 int
359 toe_syncache_expand(struct in_conninfo *inc, struct tcpopt *to,
360     struct tcphdr *th, struct socket **lsop)
361 {
362 
363 	NET_EPOCH_ASSERT();
364 
365 	return (syncache_expand(inc, to, th, lsop, NULL));
366 }
367 
368 /*
369  * General purpose check to see if a 4-tuple is in use by the kernel.  If a TCP
370  * header (presumably for an incoming SYN) is also provided, an existing 4-tuple
371  * in TIME_WAIT may be assassinated freeing it up for re-use.
372  *
373  * Note that the TCP header must have been run through tcp_fields_to_host() or
374  * equivalent.
375  */
376 int
377 toe_4tuple_check(struct in_conninfo *inc, struct tcphdr *th, struct ifnet *ifp)
378 {
379 	struct inpcb *inp;
380 
381 	if (inc->inc_flags & INC_ISIPV6) {
382 		inp = in6_pcblookup(&V_tcbinfo, &inc->inc6_faddr,
383 		    inc->inc_fport, &inc->inc6_laddr, inc->inc_lport,
384 		    INPLOOKUP_WLOCKPCB, ifp);
385 	} else {
386 		inp = in_pcblookup(&V_tcbinfo, inc->inc_faddr, inc->inc_fport,
387 		    inc->inc_laddr, inc->inc_lport, INPLOOKUP_WLOCKPCB, ifp);
388 	}
389 	if (inp != NULL) {
390 		INP_WLOCK_ASSERT(inp);
391 
392 		if ((inp->inp_flags & INP_TIMEWAIT) && th != NULL) {
393 			if (!tcp_twcheck(inp, NULL, th, NULL, 0))
394 				return (EADDRINUSE);
395 		} else {
396 			INP_WUNLOCK(inp);
397 			return (EADDRINUSE);
398 		}
399 	}
400 
401 	return (0);
402 }
403 
404 static void
405 toe_lle_event(void *arg __unused, struct llentry *lle, int evt)
406 {
407 	struct toedev *tod;
408 	struct ifnet *ifp;
409 	struct sockaddr *sa;
410 	uint8_t *lladdr;
411 	uint16_t vid, pcp;
412 	int family;
413 	struct sockaddr_in6 sin6;
414 
415 	LLE_WLOCK_ASSERT(lle);
416 
417 	ifp = lltable_get_ifp(lle->lle_tbl);
418 	family = lltable_get_af(lle->lle_tbl);
419 
420 	if (family != AF_INET && family != AF_INET6)
421 		return;
422 	/*
423 	 * Not interested if the interface's TOE capability is not enabled.
424 	 */
425 	if ((family == AF_INET && !(ifp->if_capenable & IFCAP_TOE4)) ||
426 	    (family == AF_INET6 && !(ifp->if_capenable & IFCAP_TOE6)))
427 		return;
428 
429 	tod = TOEDEV(ifp);
430 	if (tod == NULL)
431 		return;
432 
433 	sa = (struct sockaddr *)&sin6;
434 	lltable_fill_sa_entry(lle, sa);
435 
436 	vid = 0xfff;
437 	pcp = 0;
438 	if (evt != LLENTRY_RESOLVED) {
439 		/*
440 		 * LLENTRY_TIMEDOUT, LLENTRY_DELETED, LLENTRY_EXPIRED all mean
441 		 * this entry is going to be deleted.
442 		 */
443 
444 		lladdr = NULL;
445 	} else {
446 		KASSERT(lle->la_flags & LLE_VALID,
447 		    ("%s: %p resolved but not valid?", __func__, lle));
448 
449 		lladdr = (uint8_t *)lle->ll_addr;
450 		VLAN_TAG(ifp, &vid);
451 		VLAN_PCP(ifp, &pcp);
452 	}
453 
454 	tod->tod_l2_update(tod, ifp, sa, lladdr, EVL_MAKETAG(vid, pcp, 0));
455 }
456 
457 /*
458  * Returns 0 or EWOULDBLOCK on success (any other value is an error).  0 means
459  * lladdr and vtag are valid on return, EWOULDBLOCK means the TOE driver's
460  * tod_l2_update will be called later, when the entry is resolved or times out.
461  */
462 int
463 toe_l2_resolve(struct toedev *tod, struct ifnet *ifp, struct sockaddr *sa,
464     uint8_t *lladdr, uint16_t *vtag)
465 {
466 	int rc;
467 	uint16_t vid, pcp;
468 
469 	switch (sa->sa_family) {
470 #ifdef INET
471 	case AF_INET:
472 		rc = arpresolve(ifp, 0, NULL, sa, lladdr, NULL, NULL);
473 		break;
474 #endif
475 #ifdef INET6
476 	case AF_INET6:
477 		rc = nd6_resolve(ifp, 0, NULL, sa, lladdr, NULL, NULL);
478 		break;
479 #endif
480 	default:
481 		return (EPROTONOSUPPORT);
482 	}
483 
484 	if (rc == 0) {
485 		vid = 0xfff;
486 		pcp = 0;
487 		if (ifp->if_type == IFT_L2VLAN) {
488 			VLAN_TAG(ifp, &vid);
489 			VLAN_PCP(ifp, &pcp);
490 		} else if (ifp->if_pcp != IFNET_PCP_NONE) {
491 			vid = 0;
492 			pcp = ifp->if_pcp;
493 		}
494 		*vtag = EVL_MAKETAG(vid, pcp, 0);
495 	}
496 
497 	return (rc);
498 }
499 
500 void
501 toe_connect_failed(struct toedev *tod, struct inpcb *inp, int err)
502 {
503 
504 	NET_EPOCH_ASSERT();
505 	INP_WLOCK_ASSERT(inp);
506 
507 	if (!(inp->inp_flags & INP_DROPPED)) {
508 		struct tcpcb *tp = intotcpcb(inp);
509 
510 		KASSERT(tp->t_flags & TF_TOE,
511 		    ("%s: tp %p not offloaded.", __func__, tp));
512 
513 		if (err == EAGAIN) {
514 			/*
515 			 * Temporary failure during offload, take this PCB back.
516 			 * Detach from the TOE driver and do the rest of what
517 			 * TCP's pru_connect would have done if the connection
518 			 * wasn't offloaded.
519 			 */
520 
521 			tod->tod_pcb_detach(tod, tp);
522 			KASSERT(!(tp->t_flags & TF_TOE),
523 			    ("%s: tp %p still offloaded.", __func__, tp));
524 			tcp_timer_activate(tp, TT_KEEP, TP_KEEPINIT(tp));
525 			(void) tp->t_fb->tfb_tcp_output(tp);
526 		} else {
527 			tp = tcp_drop(tp, err);
528 			if (tp == NULL)
529 				INP_WLOCK(inp);	/* re-acquire */
530 		}
531 	}
532 	INP_WLOCK_ASSERT(inp);
533 }
534 
535 static int
536 toecore_load(void)
537 {
538 
539 	mtx_init(&toedev_lock, "toedev lock", NULL, MTX_DEF);
540 	TAILQ_INIT(&toedev_list);
541 
542 	listen_start_eh = EVENTHANDLER_REGISTER(tcp_offload_listen_start,
543 	    toe_listen_start_event, NULL, EVENTHANDLER_PRI_ANY);
544 	listen_stop_eh = EVENTHANDLER_REGISTER(tcp_offload_listen_stop,
545 	    toe_listen_stop_event, NULL, EVENTHANDLER_PRI_ANY);
546 	lle_event_eh = EVENTHANDLER_REGISTER(lle_event, toe_lle_event, NULL,
547 	    EVENTHANDLER_PRI_ANY);
548 
549 	return (0);
550 }
551 
552 static int
553 toecore_unload(void)
554 {
555 
556 	mtx_lock(&toedev_lock);
557 	if (!TAILQ_EMPTY(&toedev_list)) {
558 		mtx_unlock(&toedev_lock);
559 		return (EBUSY);
560 	}
561 
562 	EVENTHANDLER_DEREGISTER(tcp_offload_listen_start, listen_start_eh);
563 	EVENTHANDLER_DEREGISTER(tcp_offload_listen_stop, listen_stop_eh);
564 	EVENTHANDLER_DEREGISTER(lle_event, lle_event_eh);
565 
566 	mtx_unlock(&toedev_lock);
567 	mtx_destroy(&toedev_lock);
568 
569 	return (0);
570 }
571 
572 static int
573 toecore_mod_handler(module_t mod, int cmd, void *arg)
574 {
575 
576 	if (cmd == MOD_LOAD)
577 		return (toecore_load());
578 
579 	if (cmd == MOD_UNLOAD)
580 		return (toecore_unload());
581 
582 	return (EOPNOTSUPP);
583 }
584 
585 static moduledata_t mod_data= {
586 	"toecore",
587 	toecore_mod_handler,
588 	0
589 };
590 
591 MODULE_VERSION(toecore, 1);
592 DECLARE_MODULE(toecore, mod_data, SI_SUB_EXEC, SI_ORDER_ANY);
593