xref: /freebsd/sys/netinet/toecore.c (revision 325151a3) 
1 /*-
2  * Copyright (c) 2012 Chelsio Communications, Inc.
3  * All rights reserved.
4  * Written by: Navdeep Parhar <np@FreeBSD.org>
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 #include <sys/cdefs.h>
29 __FBSDID("$FreeBSD$");
30 
31 #include "opt_inet.h"
32 #include "opt_inet6.h"
33 
34 #include <sys/param.h>
35 #include <sys/kernel.h>
36 #include <sys/systm.h>
37 #include <sys/mbuf.h>
38 #include <sys/module.h>
39 #include <sys/types.h>
40 #include <sys/sockopt.h>
41 #include <sys/sysctl.h>
42 #include <sys/socket.h>
43 
44 #include <net/ethernet.h>
45 #include <net/if.h>
46 #include <net/if_var.h>
47 #include <net/if_types.h>
48 #include <net/if_vlan_var.h>
49 #include <net/if_llatbl.h>
50 #include <net/route.h>
51 
52 #include <netinet/if_ether.h>
53 #include <netinet/in.h>
54 #include <netinet/in_pcb.h>
55 #include <netinet/in_var.h>
56 #include <netinet6/in6_var.h>
57 #include <netinet6/in6_pcb.h>
58 #include <netinet6/nd6.h>
59 #define TCPSTATES
60 #include <netinet/tcp.h>
61 #include <netinet/tcp_fsm.h>
62 #include <netinet/tcp_timer.h>
63 #include <netinet/tcp_var.h>
64 #include <netinet/tcp_syncache.h>
65 #include <netinet/tcp_offload.h>
66 #include <netinet/toecore.h>
67 
68 static struct mtx toedev_lock;
69 static TAILQ_HEAD(, toedev) toedev_list;
70 static eventhandler_tag listen_start_eh;
71 static eventhandler_tag listen_stop_eh;
72 static eventhandler_tag lle_event_eh;
73 static eventhandler_tag route_redirect_eh;
74 
75 static int
76 toedev_connect(struct toedev *tod __unused, struct socket *so __unused,
77     struct rtentry *rt __unused, struct sockaddr *nam __unused)
78 {
79 
80 	return (ENOTSUP);
81 }
82 
83 static int
84 toedev_listen_start(struct toedev *tod __unused, struct tcpcb *tp __unused)
85 {
86 
87 	return (ENOTSUP);
88 }
89 
90 static int
91 toedev_listen_stop(struct toedev *tod __unused, struct tcpcb *tp __unused)
92 {
93 
94 	return (ENOTSUP);
95 }
96 
97 static void
98 toedev_input(struct toedev *tod __unused, struct tcpcb *tp __unused,
99     struct mbuf *m)
100 {
101 
102 	m_freem(m);
103 	return;
104 }
105 
106 static void
107 toedev_rcvd(struct toedev *tod __unused, struct tcpcb *tp __unused)
108 {
109 
110 	return;
111 }
112 
113 static int
114 toedev_output(struct toedev *tod __unused, struct tcpcb *tp __unused)
115 {
116 
117 	return (ENOTSUP);
118 }
119 
120 static void
121 toedev_pcb_detach(struct toedev *tod __unused, struct tcpcb *tp __unused)
122 {
123 
124 	return;
125 }
126 
127 static void
128 toedev_l2_update(struct toedev *tod __unused, struct ifnet *ifp __unused,
129     struct sockaddr *sa __unused, uint8_t *lladdr __unused,
130     uint16_t vtag __unused)
131 {
132 
133 	return;
134 }
135 
136 static void
137 toedev_route_redirect(struct toedev *tod __unused, struct ifnet *ifp __unused,
138     struct rtentry *rt0 __unused, struct rtentry *rt1 __unused)
139 {
140 
141 	return;
142 }
143 
144 static void
145 toedev_syncache_added(struct toedev *tod __unused, void *ctx __unused)
146 {
147 
148 	return;
149 }
150 
151 static void
152 toedev_syncache_removed(struct toedev *tod __unused, void *ctx __unused)
153 {
154 
155 	return;
156 }
157 
158 static int
159 toedev_syncache_respond(struct toedev *tod __unused, void *ctx __unused,
160     struct mbuf *m)
161 {
162 
163 	m_freem(m);
164 	return (0);
165 }
166 
167 static void
168 toedev_offload_socket(struct toedev *tod __unused, void *ctx __unused,
169     struct socket *so __unused)
170 {
171 
172 	return;
173 }
174 
175 static void
176 toedev_ctloutput(struct toedev *tod __unused, struct tcpcb *tp __unused,
177     int sopt_dir __unused, int sopt_name __unused)
178 {
179 
180 	return;
181 }
182 
183 /*
184  * Inform one or more TOE devices about a listening socket.
185  */
186 static void
187 toe_listen_start(struct inpcb *inp, void *arg)
188 {
189 	struct toedev *t, *tod;
190 	struct tcpcb *tp;
191 
192 	INP_WLOCK_ASSERT(inp);
193 	KASSERT(inp->inp_pcbinfo == &V_tcbinfo,
194 	    ("%s: inp is not a TCP inp", __func__));
195 
196 	if (inp->inp_flags & (INP_DROPPED | INP_TIMEWAIT))
197 		return;
198 
199 	tp = intotcpcb(inp);
200 	if (tp->t_state != TCPS_LISTEN)
201 		return;
202 
203 	t = arg;
204 	mtx_lock(&toedev_lock);
205 	TAILQ_FOREACH(tod, &toedev_list, link) {
206 		if (t == NULL || t == tod)
207 			tod->tod_listen_start(tod, tp);
208 	}
209 	mtx_unlock(&toedev_lock);
210 }
211 
212 static void
213 toe_listen_start_event(void *arg __unused, struct tcpcb *tp)
214 {
215 	struct inpcb *inp = tp->t_inpcb;
216 
217 	INP_WLOCK_ASSERT(inp);
218 	KASSERT(tp->t_state == TCPS_LISTEN,
219 	    ("%s: t_state %s", __func__, tcpstates[tp->t_state]));
220 
221 	toe_listen_start(inp, NULL);
222 }
223 
224 static void
225 toe_listen_stop_event(void *arg __unused, struct tcpcb *tp)
226 {
227 	struct toedev *tod;
228 #ifdef INVARIANTS
229 	struct inpcb *inp = tp->t_inpcb;
230 #endif
231 
232 	INP_WLOCK_ASSERT(inp);
233 	KASSERT(tp->t_state == TCPS_LISTEN,
234 	    ("%s: t_state %s", __func__, tcpstates[tp->t_state]));
235 
236 	mtx_lock(&toedev_lock);
237 	TAILQ_FOREACH(tod, &toedev_list, link)
238 	    tod->tod_listen_stop(tod, tp);
239 	mtx_unlock(&toedev_lock);
240 }
241 
242 /*
243  * Fill up a freshly allocated toedev struct with reasonable defaults.
244  */
245 void
246 init_toedev(struct toedev *tod)
247 {
248 
249 	tod->tod_softc = NULL;
250 
251 	/*
252 	 * Provide no-op defaults so that the kernel can call any toedev
253 	 * function without having to check whether the TOE driver supplied one
254 	 * or not.
255 	 */
256 	tod->tod_connect = toedev_connect;
257 	tod->tod_listen_start = toedev_listen_start;
258 	tod->tod_listen_stop = toedev_listen_stop;
259 	tod->tod_input = toedev_input;
260 	tod->tod_rcvd = toedev_rcvd;
261 	tod->tod_output = toedev_output;
262 	tod->tod_send_rst = toedev_output;
263 	tod->tod_send_fin = toedev_output;
264 	tod->tod_pcb_detach = toedev_pcb_detach;
265 	tod->tod_l2_update = toedev_l2_update;
266 	tod->tod_route_redirect = toedev_route_redirect;
267 	tod->tod_syncache_added = toedev_syncache_added;
268 	tod->tod_syncache_removed = toedev_syncache_removed;
269 	tod->tod_syncache_respond = toedev_syncache_respond;
270 	tod->tod_offload_socket = toedev_offload_socket;
271 	tod->tod_ctloutput = toedev_ctloutput;
272 }
273 
274 /*
275  * Register an active TOE device with the system.  This allows it to receive
276  * notifications from the kernel.
277  */
278 int
279 register_toedev(struct toedev *tod)
280 {
281 	struct toedev *t;
282 
283 	mtx_lock(&toedev_lock);
284 	TAILQ_FOREACH(t, &toedev_list, link) {
285 		if (t == tod) {
286 			mtx_unlock(&toedev_lock);
287 			return (EEXIST);
288 		}
289 	}
290 
291 	TAILQ_INSERT_TAIL(&toedev_list, tod, link);
292 	registered_toedevs++;
293 	mtx_unlock(&toedev_lock);
294 
295 	inp_apply_all(toe_listen_start, tod);
296 
297 	return (0);
298 }
299 
300 /*
301  * Remove the TOE device from the global list of active TOE devices.  It is the
302  * caller's responsibility to ensure that the TOE device is quiesced prior to
303  * this call.
304  */
305 int
306 unregister_toedev(struct toedev *tod)
307 {
308 	struct toedev *t, *t2;
309 	int rc = ENODEV;
310 
311 	mtx_lock(&toedev_lock);
312 	TAILQ_FOREACH_SAFE(t, &toedev_list, link, t2) {
313 		if (t == tod) {
314 			TAILQ_REMOVE(&toedev_list, tod, link);
315 			registered_toedevs--;
316 			rc = 0;
317 			break;
318 		}
319 	}
320 	KASSERT(registered_toedevs >= 0,
321 	    ("%s: registered_toedevs (%d) < 0", __func__, registered_toedevs));
322 	mtx_unlock(&toedev_lock);
323 	return (rc);
324 }
325 
326 void
327 toe_syncache_add(struct in_conninfo *inc, struct tcpopt *to, struct tcphdr *th,
328     struct inpcb *inp, void *tod, void *todctx)
329 {
330 	struct socket *lso = inp->inp_socket;
331 
332 	INP_WLOCK_ASSERT(inp);
333 
334 	syncache_add(inc, to, th, inp, &lso, NULL, tod, todctx);
335 }
336 
337 int
338 toe_syncache_expand(struct in_conninfo *inc, struct tcpopt *to,
339     struct tcphdr *th, struct socket **lsop)
340 {
341 
342 	INP_INFO_RLOCK_ASSERT(&V_tcbinfo);
343 
344 	return (syncache_expand(inc, to, th, lsop, NULL));
345 }
346 
347 /*
348  * General purpose check to see if a 4-tuple is in use by the kernel.  If a TCP
349  * header (presumably for an incoming SYN) is also provided, an existing 4-tuple
350  * in TIME_WAIT may be assassinated freeing it up for re-use.
351  *
352  * Note that the TCP header must have been run through tcp_fields_to_host() or
353  * equivalent.
354  */
355 int
356 toe_4tuple_check(struct in_conninfo *inc, struct tcphdr *th, struct ifnet *ifp)
357 {
358 	struct inpcb *inp;
359 
360 	if (inc->inc_flags & INC_ISIPV6) {
361 		inp = in6_pcblookup(&V_tcbinfo, &inc->inc6_faddr,
362 		    inc->inc_fport, &inc->inc6_laddr, inc->inc_lport,
363 		    INPLOOKUP_WLOCKPCB, ifp);
364 	} else {
365 		inp = in_pcblookup(&V_tcbinfo, inc->inc_faddr, inc->inc_fport,
366 		    inc->inc_laddr, inc->inc_lport, INPLOOKUP_WLOCKPCB, ifp);
367 	}
368 	if (inp != NULL) {
369 		INP_WLOCK_ASSERT(inp);
370 
371 		if ((inp->inp_flags & INP_TIMEWAIT) && th != NULL) {
372 
373 			INP_INFO_RLOCK_ASSERT(&V_tcbinfo); /* for twcheck */
374 			if (!tcp_twcheck(inp, NULL, th, NULL, 0))
375 				return (EADDRINUSE);
376 		} else {
377 			INP_WUNLOCK(inp);
378 			return (EADDRINUSE);
379 		}
380 	}
381 
382 	return (0);
383 }
384 
385 static void
386 toe_lle_event(void *arg __unused, struct llentry *lle, int evt)
387 {
388 	struct toedev *tod;
389 	struct ifnet *ifp;
390 	struct sockaddr *sa;
391 	uint8_t *lladdr;
392 	uint16_t vtag;
393 	int family;
394 	struct sockaddr_in6 sin6;
395 
396 	LLE_WLOCK_ASSERT(lle);
397 
398 	ifp = lltable_get_ifp(lle->lle_tbl);
399 	family = lltable_get_af(lle->lle_tbl);
400 
401 	if (family != AF_INET && family != AF_INET6)
402 		return;
403 	/*
404 	 * Not interested if the interface's TOE capability is not enabled.
405 	 */
406 	if ((family == AF_INET && !(ifp->if_capenable & IFCAP_TOE4)) ||
407 	    (family == AF_INET6 && !(ifp->if_capenable & IFCAP_TOE6)))
408 		return;
409 
410 	tod = TOEDEV(ifp);
411 	if (tod == NULL)
412 		return;
413 
414 	sa = (struct sockaddr *)&sin6;
415 	lltable_fill_sa_entry(lle, sa);
416 
417 	vtag = 0xfff;
418 	if (evt != LLENTRY_RESOLVED) {
419 
420 		/*
421 		 * LLENTRY_TIMEDOUT, LLENTRY_DELETED, LLENTRY_EXPIRED all mean
422 		 * this entry is going to be deleted.
423 		 */
424 
425 		lladdr = NULL;
426 	} else {
427 
428 		KASSERT(lle->la_flags & LLE_VALID,
429 		    ("%s: %p resolved but not valid?", __func__, lle));
430 
431 		lladdr = (uint8_t *)&lle->ll_addr;
432 #ifdef VLAN_TAG
433 		VLAN_TAG(ifp, &vtag);
434 #endif
435 	}
436 
437 	tod->tod_l2_update(tod, ifp, sa, lladdr, vtag);
438 }
439 
440 /*
441  * XXX: implement.
442  */
443 static void
444 toe_route_redirect_event(void *arg __unused, struct rtentry *rt0,
445     struct rtentry *rt1, struct sockaddr *sa)
446 {
447 
448 	return;
449 }
450 
451 /*
452  * Returns 0 or EWOULDBLOCK on success (any other value is an error).  0 means
453  * lladdr and vtag are valid on return, EWOULDBLOCK means the TOE driver's
454  * tod_l2_update will be called later, when the entry is resolved or times out.
455  */
456 int
457 toe_l2_resolve(struct toedev *tod, struct ifnet *ifp, struct sockaddr *sa,
458     uint8_t *lladdr, uint16_t *vtag)
459 {
460 	int rc;
461 
462 	switch (sa->sa_family) {
463 #ifdef INET
464 	case AF_INET:
465 		rc = arpresolve(ifp, 0, NULL, sa, lladdr, NULL);
466 		break;
467 #endif
468 #ifdef INET6
469 	case AF_INET6:
470 		rc = nd6_resolve(ifp, 0, NULL, sa, lladdr, NULL);
471 		break;
472 #endif
473 	default:
474 		return (EPROTONOSUPPORT);
475 	}
476 
477 	if (rc == 0) {
478 #ifdef VLAN_TAG
479 		if (VLAN_TAG(ifp, vtag) != 0)
480 #endif
481 			*vtag = 0xfff;
482 	}
483 
484 	return (rc);
485 }
486 
487 void
488 toe_connect_failed(struct toedev *tod, struct inpcb *inp, int err)
489 {
490 
491 	INP_WLOCK_ASSERT(inp);
492 
493 	if (!(inp->inp_flags & INP_DROPPED)) {
494 		struct tcpcb *tp = intotcpcb(inp);
495 
496 		KASSERT(tp->t_flags & TF_TOE,
497 		    ("%s: tp %p not offloaded.", __func__, tp));
498 
499 		if (err == EAGAIN) {
500 
501 			/*
502 			 * Temporary failure during offload, take this PCB back.
503 			 * Detach from the TOE driver and do the rest of what
504 			 * TCP's pru_connect would have done if the connection
505 			 * wasn't offloaded.
506 			 */
507 
508 			tod->tod_pcb_detach(tod, tp);
509 			KASSERT(!(tp->t_flags & TF_TOE),
510 			    ("%s: tp %p still offloaded.", __func__, tp));
511 			tcp_timer_activate(tp, TT_KEEP, TP_KEEPINIT(tp));
512 			(void) tcp_output(tp);
513 		} else {
514 
515 			INP_INFO_RLOCK_ASSERT(&V_tcbinfo);
516 			tp = tcp_drop(tp, err);
517 			if (tp == NULL)
518 				INP_WLOCK(inp);	/* re-acquire */
519 		}
520 	}
521 	INP_WLOCK_ASSERT(inp);
522 }
523 
524 static int
525 toecore_load(void)
526 {
527 
528 	mtx_init(&toedev_lock, "toedev lock", NULL, MTX_DEF);
529 	TAILQ_INIT(&toedev_list);
530 
531 	listen_start_eh = EVENTHANDLER_REGISTER(tcp_offload_listen_start,
532 	    toe_listen_start_event, NULL, EVENTHANDLER_PRI_ANY);
533 	listen_stop_eh = EVENTHANDLER_REGISTER(tcp_offload_listen_stop,
534 	    toe_listen_stop_event, NULL, EVENTHANDLER_PRI_ANY);
535 	lle_event_eh = EVENTHANDLER_REGISTER(lle_event, toe_lle_event, NULL,
536 	    EVENTHANDLER_PRI_ANY);
537 	route_redirect_eh = EVENTHANDLER_REGISTER(route_redirect_event,
538 	    toe_route_redirect_event, NULL, EVENTHANDLER_PRI_ANY);
539 
540 	return (0);
541 }
542 
543 static int
544 toecore_unload(void)
545 {
546 
547 	mtx_lock(&toedev_lock);
548 	if (!TAILQ_EMPTY(&toedev_list)) {
549 		mtx_unlock(&toedev_lock);
550 		return (EBUSY);
551 	}
552 
553 	EVENTHANDLER_DEREGISTER(tcp_offload_listen_start, listen_start_eh);
554 	EVENTHANDLER_DEREGISTER(tcp_offload_listen_stop, listen_stop_eh);
555 	EVENTHANDLER_DEREGISTER(lle_event, lle_event_eh);
556 	EVENTHANDLER_DEREGISTER(route_redirect_event, route_redirect_eh);
557 
558 	mtx_unlock(&toedev_lock);
559 	mtx_destroy(&toedev_lock);
560 
561 	return (0);
562 }
563 
564 static int
565 toecore_mod_handler(module_t mod, int cmd, void *arg)
566 {
567 
568 	if (cmd == MOD_LOAD)
569 		return (toecore_load());
570 
571 	if (cmd == MOD_UNLOAD)
572 		return (toecore_unload());
573 
574 	return (EOPNOTSUPP);
575 }
576 
577 static moduledata_t mod_data= {
578 	"toecore",
579 	toecore_mod_handler,
580 	0
581 };
582 
583 MODULE_VERSION(toecore, 1);
584 DECLARE_MODULE(toecore, mod_data, SI_SUB_EXEC, SI_ORDER_ANY);
585