xref: /freebsd/sys/netinet/toecore.c (revision c6ec7d31830ab1c80edae95ad5e4b9dba10c47ac)
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_types.h>
47 #include <net/if_vlan_var.h>
48 #include <net/if_llatbl.h>
49 #include <net/route.h>
50 
51 #include <netinet/if_ether.h>
52 #include <netinet/in.h>
53 #include <netinet/in_pcb.h>
54 #include <netinet/in_var.h>
55 #include <netinet6/nd6.h>
56 #define TCPSTATES
57 #include <netinet/tcp.h>
58 #include <netinet/tcp_fsm.h>
59 #include <netinet/tcp_timer.h>
60 #include <netinet/tcp_var.h>
61 #include <netinet/tcp_syncache.h>
62 #include <netinet/tcp_offload.h>
63 #include <netinet/toecore.h>
64 
65 static struct mtx toedev_lock;
66 static TAILQ_HEAD(, toedev) toedev_list;
67 static eventhandler_tag listen_start_eh;
68 static eventhandler_tag listen_stop_eh;
69 static eventhandler_tag lle_event_eh;
70 static eventhandler_tag route_redirect_eh;
71 
72 static int
73 toedev_connect(struct toedev *tod __unused, struct socket *so __unused,
74     struct rtentry *rt __unused, struct sockaddr *nam __unused)
75 {
76 
77 	return (ENOTSUP);
78 }
79 
80 static int
81 toedev_listen_start(struct toedev *tod __unused, struct tcpcb *tp __unused)
82 {
83 
84 	return (ENOTSUP);
85 }
86 
87 static int
88 toedev_listen_stop(struct toedev *tod __unused, struct tcpcb *tp __unused)
89 {
90 
91 	return (ENOTSUP);
92 }
93 
94 static void
95 toedev_input(struct toedev *tod __unused, struct tcpcb *tp __unused,
96     struct mbuf *m)
97 {
98 
99 	m_freem(m);
100 	return;
101 }
102 
103 static void
104 toedev_rcvd(struct toedev *tod __unused, struct tcpcb *tp __unused)
105 {
106 
107 	return;
108 }
109 
110 static int
111 toedev_output(struct toedev *tod __unused, struct tcpcb *tp __unused)
112 {
113 
114 	return (ENOTSUP);
115 }
116 
117 static void
118 toedev_pcb_detach(struct toedev *tod __unused, struct tcpcb *tp __unused)
119 {
120 
121 	return;
122 }
123 
124 static void
125 toedev_l2_update(struct toedev *tod __unused, struct ifnet *ifp __unused,
126     struct sockaddr *sa __unused, uint8_t *lladdr __unused,
127     uint16_t vtag __unused)
128 {
129 
130 	return;
131 }
132 
133 static void
134 toedev_route_redirect(struct toedev *tod __unused, struct ifnet *ifp __unused,
135     struct rtentry *rt0 __unused, struct rtentry *rt1 __unused)
136 {
137 
138 	return;
139 }
140 
141 static void
142 toedev_syncache_added(struct toedev *tod __unused, void *ctx __unused)
143 {
144 
145 	return;
146 }
147 
148 static void
149 toedev_syncache_removed(struct toedev *tod __unused, void *ctx __unused)
150 {
151 
152 	return;
153 }
154 
155 static int
156 toedev_syncache_respond(struct toedev *tod __unused, void *ctx __unused,
157     struct mbuf *m)
158 {
159 
160 	m_freem(m);
161 	return (0);
162 }
163 
164 static void
165 toedev_offload_socket(struct toedev *tod __unused, void *ctx __unused,
166     struct socket *so __unused)
167 {
168 
169 	return;
170 }
171 
172 static void
173 toedev_ctloutput(struct toedev *tod __unused, struct tcpcb *tp __unused,
174     int sopt_dir __unused, int sopt_name __unused)
175 {
176 
177 	return;
178 }
179 
180 /*
181  * Inform one or more TOE devices about a listening socket.
182  */
183 static void
184 toe_listen_start(struct inpcb *inp, void *arg)
185 {
186 	struct toedev *t, *tod;
187 	struct tcpcb *tp;
188 
189 	INP_WLOCK_ASSERT(inp);
190 	KASSERT(inp->inp_pcbinfo == &V_tcbinfo,
191 	    ("%s: inp is not a TCP inp", __func__));
192 
193 	if (inp->inp_flags & (INP_DROPPED | INP_TIMEWAIT))
194 		return;
195 
196 	tp = intotcpcb(inp);
197 	if (tp->t_state != TCPS_LISTEN)
198 		return;
199 
200 	t = arg;
201 	mtx_lock(&toedev_lock);
202 	TAILQ_FOREACH(tod, &toedev_list, link) {
203 		if (t == NULL || t == tod)
204 			tod->tod_listen_start(tod, tp);
205 	}
206 	mtx_unlock(&toedev_lock);
207 }
208 
209 static void
210 toe_listen_start_event(void *arg __unused, struct tcpcb *tp)
211 {
212 	struct inpcb *inp = tp->t_inpcb;
213 
214 	INP_WLOCK_ASSERT(inp);
215 	KASSERT(tp->t_state == TCPS_LISTEN,
216 	    ("%s: t_state %s", __func__, tcpstates[tp->t_state]));
217 
218 	toe_listen_start(inp, NULL);
219 }
220 
221 static void
222 toe_listen_stop_event(void *arg __unused, struct tcpcb *tp)
223 {
224 	struct toedev *tod;
225 #ifdef INVARIANTS
226 	struct inpcb *inp = tp->t_inpcb;
227 #endif
228 
229 	INP_WLOCK_ASSERT(inp);
230 	KASSERT(tp->t_state == TCPS_LISTEN,
231 	    ("%s: t_state %s", __func__, tcpstates[tp->t_state]));
232 
233 	mtx_lock(&toedev_lock);
234 	TAILQ_FOREACH(tod, &toedev_list, link)
235 	    tod->tod_listen_stop(tod, tp);
236 	mtx_unlock(&toedev_lock);
237 }
238 
239 /*
240  * Fill up a freshly allocated toedev struct with reasonable defaults.
241  */
242 void
243 init_toedev(struct toedev *tod)
244 {
245 
246 	tod->tod_softc = NULL;
247 
248 	/*
249 	 * Provide no-op defaults so that the kernel can call any toedev
250 	 * function without having to check whether the TOE driver supplied one
251 	 * or not.
252 	 */
253 	tod->tod_connect = toedev_connect;
254 	tod->tod_listen_start = toedev_listen_start;
255 	tod->tod_listen_stop = toedev_listen_stop;
256 	tod->tod_input = toedev_input;
257 	tod->tod_rcvd = toedev_rcvd;
258 	tod->tod_output = toedev_output;
259 	tod->tod_send_rst = toedev_output;
260 	tod->tod_send_fin = toedev_output;
261 	tod->tod_pcb_detach = toedev_pcb_detach;
262 	tod->tod_l2_update = toedev_l2_update;
263 	tod->tod_route_redirect = toedev_route_redirect;
264 	tod->tod_syncache_added = toedev_syncache_added;
265 	tod->tod_syncache_removed = toedev_syncache_removed;
266 	tod->tod_syncache_respond = toedev_syncache_respond;
267 	tod->tod_offload_socket = toedev_offload_socket;
268 	tod->tod_ctloutput = toedev_ctloutput;
269 }
270 
271 /*
272  * Register an active TOE device with the system.  This allows it to receive
273  * notifications from the kernel.
274  */
275 int
276 register_toedev(struct toedev *tod)
277 {
278 	struct toedev *t;
279 
280 	mtx_lock(&toedev_lock);
281 	TAILQ_FOREACH(t, &toedev_list, link) {
282 		if (t == tod) {
283 			mtx_unlock(&toedev_lock);
284 			return (EEXIST);
285 		}
286 	}
287 
288 	TAILQ_INSERT_TAIL(&toedev_list, tod, link);
289 	registered_toedevs++;
290 	mtx_unlock(&toedev_lock);
291 
292 	inp_apply_all(toe_listen_start, tod);
293 
294 	return (0);
295 }
296 
297 /*
298  * Remove the TOE device from the global list of active TOE devices.  It is the
299  * caller's responsibility to ensure that the TOE device is quiesced prior to
300  * this call.
301  */
302 int
303 unregister_toedev(struct toedev *tod)
304 {
305 	struct toedev *t, *t2;
306 	int rc = ENODEV;
307 
308 	mtx_lock(&toedev_lock);
309 	TAILQ_FOREACH_SAFE(t, &toedev_list, link, t2) {
310 		if (t == tod) {
311 			TAILQ_REMOVE(&toedev_list, tod, link);
312 			registered_toedevs--;
313 			rc = 0;
314 			break;
315 		}
316 	}
317 	KASSERT(registered_toedevs >= 0,
318 	    ("%s: registered_toedevs (%d) < 0", __func__, registered_toedevs));
319 	mtx_unlock(&toedev_lock);
320 	return (rc);
321 }
322 
323 void
324 toe_syncache_add(struct in_conninfo *inc, struct tcpopt *to, struct tcphdr *th,
325     struct inpcb *inp, void *tod, void *todctx)
326 {
327 	struct socket *lso = inp->inp_socket;
328 
329 	INP_INFO_WLOCK_ASSERT(&V_tcbinfo);
330 	INP_WLOCK_ASSERT(inp);
331 
332 	syncache_add(inc, to, th, inp, &lso, NULL, tod, todctx);
333 }
334 
335 int
336 toe_syncache_expand(struct in_conninfo *inc, struct tcpopt *to,
337     struct tcphdr *th, struct socket **lsop)
338 {
339 
340 	INP_INFO_WLOCK_ASSERT(&V_tcbinfo);
341 
342 	return (syncache_expand(inc, to, th, lsop, NULL));
343 }
344 
345 /*
346  * General purpose check to see if a 4-tuple is in use by the kernel.  If a TCP
347  * header (presumably for an incoming SYN) is also provided, an existing 4-tuple
348  * in TIME_WAIT may be assassinated freeing it up for re-use.
349  *
350  * Note that the TCP header must have been run through tcp_fields_to_host() or
351  * equivalent.
352  */
353 int
354 toe_4tuple_check(struct in_conninfo *inc, struct tcphdr *th, struct ifnet *ifp)
355 {
356 	struct inpcb *inp;
357 
358 	if (inc->inc_flags & INC_ISIPV6)
359 		return (ENOSYS);	/* XXX: implement */
360 
361 	inp = in_pcblookup(&V_tcbinfo, inc->inc_faddr, inc->inc_fport,
362 	    inc->inc_laddr, inc->inc_lport, INPLOOKUP_WLOCKPCB, ifp);
363 	if (inp != NULL) {
364 		INP_WLOCK_ASSERT(inp);
365 
366 		if ((inp->inp_flags & INP_TIMEWAIT) && th != NULL) {
367 
368 			INP_INFO_WLOCK_ASSERT(&V_tcbinfo); /* for twcheck */
369 			if (!tcp_twcheck(inp, NULL, th, NULL, 0))
370 				return (EADDRINUSE);
371 		} else {
372 			INP_WUNLOCK(inp);
373 			return (EADDRINUSE);
374 		}
375 	}
376 
377 	return (0);
378 }
379 
380 static void
381 toe_lle_event(void *arg __unused, struct llentry *lle, int evt)
382 {
383 	struct toedev *tod;
384 	struct ifnet *ifp;
385 	struct sockaddr *sa;
386 	uint8_t *lladdr;
387 	uint16_t vtag;
388 
389 	LLE_WLOCK_ASSERT(lle);
390 
391 	ifp = lle->lle_tbl->llt_ifp;
392 	sa = L3_ADDR(lle);
393 
394 	KASSERT(sa->sa_family == AF_INET || sa->sa_family == AF_INET6,
395 	    ("%s: lle_event %d for lle %p but sa %p !INET && !INET6",
396 	    __func__, evt, lle, sa));
397 
398 	/*
399 	 * Not interested if the interface's TOE capability is not enabled.
400 	 */
401 	if ((sa->sa_family == AF_INET && !(ifp->if_capenable & IFCAP_TOE4)) ||
402 	    (sa->sa_family == AF_INET6 && !(ifp->if_capenable & IFCAP_TOE6)))
403 		return;
404 
405 	tod = TOEDEV(ifp);
406 	if (tod == NULL)
407 		return;
408 
409 	vtag = 0xfff;
410 	if (evt != LLENTRY_RESOLVED) {
411 
412 		/*
413 		 * LLENTRY_TIMEDOUT, LLENTRY_DELETED, LLENTRY_EXPIRED all mean
414 		 * this entry is going to be deleted.
415 		 */
416 
417 		lladdr = NULL;
418 	} else {
419 
420 		KASSERT(lle->la_flags & LLE_VALID,
421 		    ("%s: %p resolved but not valid?", __func__, lle));
422 
423 		lladdr = (uint8_t *)&lle->ll_addr;
424 #ifdef VLAN_TAG
425 		VLAN_TAG(ifp, &vtag);
426 #endif
427 	}
428 
429 	tod->tod_l2_update(tod, ifp, sa, lladdr, vtag);
430 }
431 
432 /*
433  * XXX: implement.
434  */
435 static void
436 toe_route_redirect_event(void *arg __unused, struct rtentry *rt0,
437     struct rtentry *rt1, struct sockaddr *sa)
438 {
439 
440 	return;
441 }
442 
443 /*
444  * Returns 0 or EWOULDBLOCK on success (any other value is an error).  0 means
445  * lladdr and vtag are valid on return, EWOULDBLOCK means the TOE driver's
446  * tod_l2_update will be called later, when the entry is resolved or times out.
447  */
448 int
449 toe_l2_resolve(struct toedev *tod, struct ifnet *ifp, struct sockaddr *sa,
450     uint8_t *lladdr, uint16_t *vtag)
451 {
452 	struct llentry *lle;
453 	int rc;
454 
455 	switch (sa->sa_family) {
456 #ifdef INET
457 	case AF_INET:
458 		rc = arpresolve(ifp, NULL, NULL, sa, lladdr, &lle);
459 		break;
460 #endif
461 #ifdef INET6
462 	case AF_INET6:
463 		rc = nd6_storelladdr(ifp, NULL, sa, lladdr, &lle);
464 		break;
465 #endif
466 	default:
467 		return (EPROTONOSUPPORT);
468 	}
469 
470 	if (rc == 0) {
471 #ifdef VLAN_TAG
472 		if (VLAN_TAG(ifp, vtag) != 0)
473 #endif
474 			*vtag = 0xfff;
475 	}
476 
477 	return (rc);
478 }
479 
480 void
481 toe_connect_failed(struct toedev *tod, struct inpcb *inp, int err)
482 {
483 
484 	INP_WLOCK_ASSERT(inp);
485 
486 	if (!(inp->inp_flags & INP_DROPPED)) {
487 		struct tcpcb *tp = intotcpcb(inp);
488 
489 		KASSERT(tp->t_flags & TF_TOE,
490 		    ("%s: tp %p not offloaded.", __func__, tp));
491 
492 		if (err == EAGAIN) {
493 
494 			/*
495 			 * Temporary failure during offload, take this PCB back.
496 			 * Detach from the TOE driver and do the rest of what
497 			 * TCP's pru_connect would have done if the connection
498 			 * wasn't offloaded.
499 			 */
500 
501 			tod->tod_pcb_detach(tod, tp);
502 			KASSERT(!(tp->t_flags & TF_TOE),
503 			    ("%s: tp %p still offloaded.", __func__, tp));
504 			tcp_timer_activate(tp, TT_KEEP, TP_KEEPINIT(tp));
505 			(void) tcp_output(tp);
506 		} else {
507 
508 			INP_INFO_WLOCK_ASSERT(&V_tcbinfo);
509 			tp = tcp_drop(tp, err);
510 			if (tp == NULL)
511 				INP_WLOCK(inp);	/* re-acquire */
512 		}
513 	}
514 	INP_WLOCK_ASSERT(inp);
515 }
516 
517 static int
518 toecore_load(void)
519 {
520 
521 	mtx_init(&toedev_lock, "toedev lock", NULL, MTX_DEF);
522 	TAILQ_INIT(&toedev_list);
523 
524 	listen_start_eh = EVENTHANDLER_REGISTER(tcp_offload_listen_start,
525 	    toe_listen_start_event, NULL, EVENTHANDLER_PRI_ANY);
526 	listen_stop_eh = EVENTHANDLER_REGISTER(tcp_offload_listen_stop,
527 	    toe_listen_stop_event, NULL, EVENTHANDLER_PRI_ANY);
528 	lle_event_eh = EVENTHANDLER_REGISTER(lle_event, toe_lle_event, NULL,
529 	    EVENTHANDLER_PRI_ANY);
530 	route_redirect_eh = EVENTHANDLER_REGISTER(route_redirect_event,
531 	    toe_route_redirect_event, NULL, EVENTHANDLER_PRI_ANY);
532 
533 	return (0);
534 }
535 
536 static int
537 toecore_unload(void)
538 {
539 
540 	mtx_lock(&toedev_lock);
541 	if (!TAILQ_EMPTY(&toedev_list)) {
542 		mtx_unlock(&toedev_lock);
543 		return (EBUSY);
544 	}
545 
546 	EVENTHANDLER_DEREGISTER(tcp_offload_listen_start, listen_start_eh);
547 	EVENTHANDLER_DEREGISTER(tcp_offload_listen_stop, listen_stop_eh);
548 	EVENTHANDLER_DEREGISTER(lle_event, lle_event_eh);
549 	EVENTHANDLER_DEREGISTER(route_redirect_event, route_redirect_eh);
550 
551 	mtx_unlock(&toedev_lock);
552 	mtx_destroy(&toedev_lock);
553 
554 	return (0);
555 }
556 
557 static int
558 toecore_mod_handler(module_t mod, int cmd, void *arg)
559 {
560 
561 	if (cmd == MOD_LOAD)
562 		return (toecore_load());
563 
564 	if (cmd == MOD_UNLOAD)
565 		return (toecore_unload());
566 
567 	return (EOPNOTSUPP);
568 }
569 
570 static moduledata_t mod_data= {
571 	"toecore",
572 	toecore_mod_handler,
573 	0
574 };
575 
576 MODULE_VERSION(toecore, 1);
577 DECLARE_MODULE(toecore, mod_data, SI_SUB_EXEC, SI_ORDER_ANY);
578