xref: /freebsd/sys/netinet/toecore.c (revision 807b6a646a0a0dbc258bf239468b5d9f901d1f92)
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 
74 static int
75 toedev_connect(struct toedev *tod __unused, struct socket *so __unused,
76     struct rtentry *rt __unused, struct sockaddr *nam __unused)
77 {
78 
79 	return (ENOTSUP);
80 }
81 
82 static int
83 toedev_listen_start(struct toedev *tod __unused, struct tcpcb *tp __unused)
84 {
85 
86 	return (ENOTSUP);
87 }
88 
89 static int
90 toedev_listen_stop(struct toedev *tod __unused, struct tcpcb *tp __unused)
91 {
92 
93 	return (ENOTSUP);
94 }
95 
96 static void
97 toedev_input(struct toedev *tod __unused, struct tcpcb *tp __unused,
98     struct mbuf *m)
99 {
100 
101 	m_freem(m);
102 	return;
103 }
104 
105 static void
106 toedev_rcvd(struct toedev *tod __unused, struct tcpcb *tp __unused)
107 {
108 
109 	return;
110 }
111 
112 static int
113 toedev_output(struct toedev *tod __unused, struct tcpcb *tp __unused)
114 {
115 
116 	return (ENOTSUP);
117 }
118 
119 static void
120 toedev_pcb_detach(struct toedev *tod __unused, struct tcpcb *tp __unused)
121 {
122 
123 	return;
124 }
125 
126 static void
127 toedev_l2_update(struct toedev *tod __unused, struct ifnet *ifp __unused,
128     struct sockaddr *sa __unused, uint8_t *lladdr __unused,
129     uint16_t vtag __unused)
130 {
131 
132 	return;
133 }
134 
135 static void
136 toedev_route_redirect(struct toedev *tod __unused, struct ifnet *ifp __unused,
137     struct rtentry *rt0 __unused, struct rtentry *rt1 __unused)
138 {
139 
140 	return;
141 }
142 
143 static void
144 toedev_syncache_added(struct toedev *tod __unused, void *ctx __unused)
145 {
146 
147 	return;
148 }
149 
150 static void
151 toedev_syncache_removed(struct toedev *tod __unused, void *ctx __unused)
152 {
153 
154 	return;
155 }
156 
157 static int
158 toedev_syncache_respond(struct toedev *tod __unused, void *ctx __unused,
159     struct mbuf *m)
160 {
161 
162 	m_freem(m);
163 	return (0);
164 }
165 
166 static void
167 toedev_offload_socket(struct toedev *tod __unused, void *ctx __unused,
168     struct socket *so __unused)
169 {
170 
171 	return;
172 }
173 
174 static void
175 toedev_ctloutput(struct toedev *tod __unused, struct tcpcb *tp __unused,
176     int sopt_dir __unused, int sopt_name __unused)
177 {
178 
179 	return;
180 }
181 
182 /*
183  * Inform one or more TOE devices about a listening socket.
184  */
185 static void
186 toe_listen_start(struct inpcb *inp, void *arg)
187 {
188 	struct toedev *t, *tod;
189 	struct tcpcb *tp;
190 
191 	INP_WLOCK_ASSERT(inp);
192 	KASSERT(inp->inp_pcbinfo == &V_tcbinfo,
193 	    ("%s: inp is not a TCP inp", __func__));
194 
195 	if (inp->inp_flags & (INP_DROPPED | INP_TIMEWAIT))
196 		return;
197 
198 	tp = intotcpcb(inp);
199 	if (tp->t_state != TCPS_LISTEN)
200 		return;
201 
202 	t = arg;
203 	mtx_lock(&toedev_lock);
204 	TAILQ_FOREACH(tod, &toedev_list, link) {
205 		if (t == NULL || t == tod)
206 			tod->tod_listen_start(tod, tp);
207 	}
208 	mtx_unlock(&toedev_lock);
209 }
210 
211 static void
212 toe_listen_start_event(void *arg __unused, struct tcpcb *tp)
213 {
214 	struct inpcb *inp = tp->t_inpcb;
215 
216 	INP_WLOCK_ASSERT(inp);
217 	KASSERT(tp->t_state == TCPS_LISTEN,
218 	    ("%s: t_state %s", __func__, tcpstates[tp->t_state]));
219 
220 	toe_listen_start(inp, NULL);
221 }
222 
223 static void
224 toe_listen_stop_event(void *arg __unused, struct tcpcb *tp)
225 {
226 	struct toedev *tod;
227 #ifdef INVARIANTS
228 	struct inpcb *inp = tp->t_inpcb;
229 #endif
230 
231 	INP_WLOCK_ASSERT(inp);
232 	KASSERT(tp->t_state == TCPS_LISTEN,
233 	    ("%s: t_state %s", __func__, tcpstates[tp->t_state]));
234 
235 	mtx_lock(&toedev_lock);
236 	TAILQ_FOREACH(tod, &toedev_list, link)
237 	    tod->tod_listen_stop(tod, tp);
238 	mtx_unlock(&toedev_lock);
239 }
240 
241 /*
242  * Fill up a freshly allocated toedev struct with reasonable defaults.
243  */
244 void
245 init_toedev(struct toedev *tod)
246 {
247 
248 	tod->tod_softc = NULL;
249 
250 	/*
251 	 * Provide no-op defaults so that the kernel can call any toedev
252 	 * function without having to check whether the TOE driver supplied one
253 	 * or not.
254 	 */
255 	tod->tod_connect = toedev_connect;
256 	tod->tod_listen_start = toedev_listen_start;
257 	tod->tod_listen_stop = toedev_listen_stop;
258 	tod->tod_input = toedev_input;
259 	tod->tod_rcvd = toedev_rcvd;
260 	tod->tod_output = toedev_output;
261 	tod->tod_send_rst = toedev_output;
262 	tod->tod_send_fin = toedev_output;
263 	tod->tod_pcb_detach = toedev_pcb_detach;
264 	tod->tod_l2_update = toedev_l2_update;
265 	tod->tod_route_redirect = toedev_route_redirect;
266 	tod->tod_syncache_added = toedev_syncache_added;
267 	tod->tod_syncache_removed = toedev_syncache_removed;
268 	tod->tod_syncache_respond = toedev_syncache_respond;
269 	tod->tod_offload_socket = toedev_offload_socket;
270 	tod->tod_ctloutput = toedev_ctloutput;
271 }
272 
273 /*
274  * Register an active TOE device with the system.  This allows it to receive
275  * notifications from the kernel.
276  */
277 int
278 register_toedev(struct toedev *tod)
279 {
280 	struct toedev *t;
281 
282 	mtx_lock(&toedev_lock);
283 	TAILQ_FOREACH(t, &toedev_list, link) {
284 		if (t == tod) {
285 			mtx_unlock(&toedev_lock);
286 			return (EEXIST);
287 		}
288 	}
289 
290 	TAILQ_INSERT_TAIL(&toedev_list, tod, link);
291 	registered_toedevs++;
292 	mtx_unlock(&toedev_lock);
293 
294 	inp_apply_all(toe_listen_start, tod);
295 
296 	return (0);
297 }
298 
299 /*
300  * Remove the TOE device from the global list of active TOE devices.  It is the
301  * caller's responsibility to ensure that the TOE device is quiesced prior to
302  * this call.
303  */
304 int
305 unregister_toedev(struct toedev *tod)
306 {
307 	struct toedev *t, *t2;
308 	int rc = ENODEV;
309 
310 	mtx_lock(&toedev_lock);
311 	TAILQ_FOREACH_SAFE(t, &toedev_list, link, t2) {
312 		if (t == tod) {
313 			TAILQ_REMOVE(&toedev_list, tod, link);
314 			registered_toedevs--;
315 			rc = 0;
316 			break;
317 		}
318 	}
319 	KASSERT(registered_toedevs >= 0,
320 	    ("%s: registered_toedevs (%d) < 0", __func__, registered_toedevs));
321 	mtx_unlock(&toedev_lock);
322 	return (rc);
323 }
324 
325 void
326 toe_syncache_add(struct in_conninfo *inc, struct tcpopt *to, struct tcphdr *th,
327     struct inpcb *inp, void *tod, void *todctx)
328 {
329 	struct socket *lso = inp->inp_socket;
330 
331 	INP_WLOCK_ASSERT(inp);
332 
333 	syncache_add(inc, to, th, inp, &lso, NULL, tod, todctx);
334 }
335 
336 int
337 toe_syncache_expand(struct in_conninfo *inc, struct tcpopt *to,
338     struct tcphdr *th, struct socket **lsop)
339 {
340 
341 	INP_INFO_RLOCK_ASSERT(&V_tcbinfo);
342 
343 	return (syncache_expand(inc, to, th, lsop, NULL));
344 }
345 
346 /*
347  * General purpose check to see if a 4-tuple is in use by the kernel.  If a TCP
348  * header (presumably for an incoming SYN) is also provided, an existing 4-tuple
349  * in TIME_WAIT may be assassinated freeing it up for re-use.
350  *
351  * Note that the TCP header must have been run through tcp_fields_to_host() or
352  * equivalent.
353  */
354 int
355 toe_4tuple_check(struct in_conninfo *inc, struct tcphdr *th, struct ifnet *ifp)
356 {
357 	struct inpcb *inp;
358 
359 	if (inc->inc_flags & INC_ISIPV6) {
360 		inp = in6_pcblookup(&V_tcbinfo, &inc->inc6_faddr,
361 		    inc->inc_fport, &inc->inc6_laddr, inc->inc_lport,
362 		    INPLOOKUP_WLOCKPCB, ifp);
363 	} else {
364 		inp = in_pcblookup(&V_tcbinfo, inc->inc_faddr, inc->inc_fport,
365 		    inc->inc_laddr, inc->inc_lport, INPLOOKUP_WLOCKPCB, ifp);
366 	}
367 	if (inp != NULL) {
368 		INP_WLOCK_ASSERT(inp);
369 
370 		if ((inp->inp_flags & INP_TIMEWAIT) && th != NULL) {
371 
372 			INP_INFO_RLOCK_ASSERT(&V_tcbinfo); /* for twcheck */
373 			if (!tcp_twcheck(inp, NULL, th, NULL, 0))
374 				return (EADDRINUSE);
375 		} else {
376 			INP_WUNLOCK(inp);
377 			return (EADDRINUSE);
378 		}
379 	}
380 
381 	return (0);
382 }
383 
384 static void
385 toe_lle_event(void *arg __unused, struct llentry *lle, int evt)
386 {
387 	struct toedev *tod;
388 	struct ifnet *ifp;
389 	struct sockaddr *sa;
390 	uint8_t *lladdr;
391 	uint16_t vtag;
392 	int family;
393 	struct sockaddr_in6 sin6;
394 
395 	LLE_WLOCK_ASSERT(lle);
396 
397 	ifp = lltable_get_ifp(lle->lle_tbl);
398 	family = lltable_get_af(lle->lle_tbl);
399 
400 	if (family != AF_INET && family != AF_INET6)
401 		return;
402 	/*
403 	 * Not interested if the interface's TOE capability is not enabled.
404 	 */
405 	if ((family == AF_INET && !(ifp->if_capenable & IFCAP_TOE4)) ||
406 	    (family == AF_INET6 && !(ifp->if_capenable & IFCAP_TOE6)))
407 		return;
408 
409 	tod = TOEDEV(ifp);
410 	if (tod == NULL)
411 		return;
412 
413 	sa = (struct sockaddr *)&sin6;
414 	lltable_fill_sa_entry(lle, sa);
415 
416 	vtag = 0xfff;
417 	if (evt != LLENTRY_RESOLVED) {
418 
419 		/*
420 		 * LLENTRY_TIMEDOUT, LLENTRY_DELETED, LLENTRY_EXPIRED all mean
421 		 * this entry is going to be deleted.
422 		 */
423 
424 		lladdr = NULL;
425 	} else {
426 
427 		KASSERT(lle->la_flags & LLE_VALID,
428 		    ("%s: %p resolved but not valid?", __func__, lle));
429 
430 		lladdr = (uint8_t *)lle->ll_addr;
431 #ifdef VLAN_TAG
432 		VLAN_TAG(ifp, &vtag);
433 #endif
434 	}
435 
436 	tod->tod_l2_update(tod, ifp, sa, lladdr, vtag);
437 }
438 
439 /*
440  * Returns 0 or EWOULDBLOCK on success (any other value is an error).  0 means
441  * lladdr and vtag are valid on return, EWOULDBLOCK means the TOE driver's
442  * tod_l2_update will be called later, when the entry is resolved or times out.
443  */
444 int
445 toe_l2_resolve(struct toedev *tod, struct ifnet *ifp, struct sockaddr *sa,
446     uint8_t *lladdr, uint16_t *vtag)
447 {
448 	int rc;
449 
450 	switch (sa->sa_family) {
451 #ifdef INET
452 	case AF_INET:
453 		rc = arpresolve(ifp, 0, NULL, sa, lladdr, NULL);
454 		break;
455 #endif
456 #ifdef INET6
457 	case AF_INET6:
458 		rc = nd6_resolve(ifp, 0, NULL, sa, lladdr, NULL);
459 		break;
460 #endif
461 	default:
462 		return (EPROTONOSUPPORT);
463 	}
464 
465 	if (rc == 0) {
466 #ifdef VLAN_TAG
467 		if (VLAN_TAG(ifp, vtag) != 0)
468 #endif
469 			*vtag = 0xfff;
470 	}
471 
472 	return (rc);
473 }
474 
475 void
476 toe_connect_failed(struct toedev *tod, struct inpcb *inp, int err)
477 {
478 
479 	INP_WLOCK_ASSERT(inp);
480 
481 	if (!(inp->inp_flags & INP_DROPPED)) {
482 		struct tcpcb *tp = intotcpcb(inp);
483 
484 		KASSERT(tp->t_flags & TF_TOE,
485 		    ("%s: tp %p not offloaded.", __func__, tp));
486 
487 		if (err == EAGAIN) {
488 
489 			/*
490 			 * Temporary failure during offload, take this PCB back.
491 			 * Detach from the TOE driver and do the rest of what
492 			 * TCP's pru_connect would have done if the connection
493 			 * wasn't offloaded.
494 			 */
495 
496 			tod->tod_pcb_detach(tod, tp);
497 			KASSERT(!(tp->t_flags & TF_TOE),
498 			    ("%s: tp %p still offloaded.", __func__, tp));
499 			tcp_timer_activate(tp, TT_KEEP, TP_KEEPINIT(tp));
500 			(void) tp->t_fb->tfb_tcp_output(tp);
501 		} else {
502 
503 			INP_INFO_RLOCK_ASSERT(&V_tcbinfo);
504 			tp = tcp_drop(tp, err);
505 			if (tp == NULL)
506 				INP_WLOCK(inp);	/* re-acquire */
507 		}
508 	}
509 	INP_WLOCK_ASSERT(inp);
510 }
511 
512 static int
513 toecore_load(void)
514 {
515 
516 	mtx_init(&toedev_lock, "toedev lock", NULL, MTX_DEF);
517 	TAILQ_INIT(&toedev_list);
518 
519 	listen_start_eh = EVENTHANDLER_REGISTER(tcp_offload_listen_start,
520 	    toe_listen_start_event, NULL, EVENTHANDLER_PRI_ANY);
521 	listen_stop_eh = EVENTHANDLER_REGISTER(tcp_offload_listen_stop,
522 	    toe_listen_stop_event, NULL, EVENTHANDLER_PRI_ANY);
523 	lle_event_eh = EVENTHANDLER_REGISTER(lle_event, toe_lle_event, NULL,
524 	    EVENTHANDLER_PRI_ANY);
525 
526 	return (0);
527 }
528 
529 static int
530 toecore_unload(void)
531 {
532 
533 	mtx_lock(&toedev_lock);
534 	if (!TAILQ_EMPTY(&toedev_list)) {
535 		mtx_unlock(&toedev_lock);
536 		return (EBUSY);
537 	}
538 
539 	EVENTHANDLER_DEREGISTER(tcp_offload_listen_start, listen_start_eh);
540 	EVENTHANDLER_DEREGISTER(tcp_offload_listen_stop, listen_stop_eh);
541 	EVENTHANDLER_DEREGISTER(lle_event, lle_event_eh);
542 
543 	mtx_unlock(&toedev_lock);
544 	mtx_destroy(&toedev_lock);
545 
546 	return (0);
547 }
548 
549 static int
550 toecore_mod_handler(module_t mod, int cmd, void *arg)
551 {
552 
553 	if (cmd == MOD_LOAD)
554 		return (toecore_load());
555 
556 	if (cmd == MOD_UNLOAD)
557 		return (toecore_unload());
558 
559 	return (EOPNOTSUPP);
560 }
561 
562 static moduledata_t mod_data= {
563 	"toecore",
564 	toecore_mod_handler,
565 	0
566 };
567 
568 MODULE_VERSION(toecore, 1);
569 DECLARE_MODULE(toecore, mod_data, SI_SUB_EXEC, SI_ORDER_ANY);
570