xref: /freebsd/sys/netinet/toecore.c (revision f5147e312f43a9050468de539aeafa072caa1a60)
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/kernel.h>
38 #include <sys/systm.h>
39 #include <sys/malloc.h>
40 #include <sys/mbuf.h>
41 #include <sys/module.h>
42 #include <sys/types.h>
43 #include <sys/sockopt.h>
44 #include <sys/sysctl.h>
45 #include <sys/socket.h>
46 
47 #include <net/ethernet.h>
48 #include <net/if.h>
49 #include <net/if_var.h>
50 #include <net/if_types.h>
51 #include <net/if_vlan_var.h>
52 #include <net/if_llatbl.h>
53 #include <net/route.h>
54 
55 #include <netinet/if_ether.h>
56 #include <netinet/in.h>
57 #include <netinet/in_pcb.h>
58 #include <netinet/in_var.h>
59 #include <netinet6/in6_var.h>
60 #include <netinet6/in6_pcb.h>
61 #include <netinet6/nd6.h>
62 #define TCPSTATES
63 #include <netinet/tcp.h>
64 #include <netinet/tcp_fsm.h>
65 #include <netinet/tcp_timer.h>
66 #include <netinet/tcp_var.h>
67 #include <netinet/tcp_syncache.h>
68 #include <netinet/tcp_offload.h>
69 #include <netinet/toecore.h>
70 
71 static struct mtx toedev_lock;
72 static TAILQ_HEAD(, toedev) toedev_list;
73 static eventhandler_tag listen_start_eh;
74 static eventhandler_tag listen_stop_eh;
75 static eventhandler_tag lle_event_eh;
76 
77 static int
78 toedev_connect(struct toedev *tod __unused, struct socket *so __unused,
79     struct rtentry *rt __unused, struct sockaddr *nam __unused)
80 {
81 
82 	return (ENOTSUP);
83 }
84 
85 static int
86 toedev_listen_start(struct toedev *tod __unused, struct tcpcb *tp __unused)
87 {
88 
89 	return (ENOTSUP);
90 }
91 
92 static int
93 toedev_listen_stop(struct toedev *tod __unused, struct tcpcb *tp __unused)
94 {
95 
96 	return (ENOTSUP);
97 }
98 
99 static void
100 toedev_input(struct toedev *tod __unused, struct tcpcb *tp __unused,
101     struct mbuf *m)
102 {
103 
104 	m_freem(m);
105 	return;
106 }
107 
108 static void
109 toedev_rcvd(struct toedev *tod __unused, struct tcpcb *tp __unused)
110 {
111 
112 	return;
113 }
114 
115 static int
116 toedev_output(struct toedev *tod __unused, struct tcpcb *tp __unused)
117 {
118 
119 	return (ENOTSUP);
120 }
121 
122 static void
123 toedev_pcb_detach(struct toedev *tod __unused, struct tcpcb *tp __unused)
124 {
125 
126 	return;
127 }
128 
129 static void
130 toedev_l2_update(struct toedev *tod __unused, struct ifnet *ifp __unused,
131     struct sockaddr *sa __unused, uint8_t *lladdr __unused,
132     uint16_t vtag __unused)
133 {
134 
135 	return;
136 }
137 
138 static void
139 toedev_route_redirect(struct toedev *tod __unused, struct ifnet *ifp __unused,
140     struct rtentry *rt0 __unused, struct rtentry *rt1 __unused)
141 {
142 
143 	return;
144 }
145 
146 static void
147 toedev_syncache_added(struct toedev *tod __unused, void *ctx __unused)
148 {
149 
150 	return;
151 }
152 
153 static void
154 toedev_syncache_removed(struct toedev *tod __unused, void *ctx __unused)
155 {
156 
157 	return;
158 }
159 
160 static int
161 toedev_syncache_respond(struct toedev *tod __unused, void *ctx __unused,
162     struct mbuf *m)
163 {
164 
165 	m_freem(m);
166 	return (0);
167 }
168 
169 static void
170 toedev_offload_socket(struct toedev *tod __unused, void *ctx __unused,
171     struct socket *so __unused)
172 {
173 
174 	return;
175 }
176 
177 static void
178 toedev_ctloutput(struct toedev *tod __unused, struct tcpcb *tp __unused,
179     int sopt_dir __unused, int sopt_name __unused)
180 {
181 
182 	return;
183 }
184 
185 /*
186  * Inform one or more TOE devices about a listening socket.
187  */
188 static void
189 toe_listen_start(struct inpcb *inp, void *arg)
190 {
191 	struct toedev *t, *tod;
192 	struct tcpcb *tp;
193 
194 	INP_WLOCK_ASSERT(inp);
195 	KASSERT(inp->inp_pcbinfo == &V_tcbinfo,
196 	    ("%s: inp is not a TCP inp", __func__));
197 
198 	if (inp->inp_flags & (INP_DROPPED | INP_TIMEWAIT))
199 		return;
200 
201 	tp = intotcpcb(inp);
202 	if (tp->t_state != TCPS_LISTEN)
203 		return;
204 
205 	t = arg;
206 	mtx_lock(&toedev_lock);
207 	TAILQ_FOREACH(tod, &toedev_list, link) {
208 		if (t == NULL || t == tod)
209 			tod->tod_listen_start(tod, tp);
210 	}
211 	mtx_unlock(&toedev_lock);
212 }
213 
214 static void
215 toe_listen_start_event(void *arg __unused, struct tcpcb *tp)
216 {
217 	struct inpcb *inp = tp->t_inpcb;
218 
219 	INP_WLOCK_ASSERT(inp);
220 	KASSERT(tp->t_state == TCPS_LISTEN,
221 	    ("%s: t_state %s", __func__, tcpstates[tp->t_state]));
222 
223 	toe_listen_start(inp, NULL);
224 }
225 
226 static void
227 toe_listen_stop_event(void *arg __unused, struct tcpcb *tp)
228 {
229 	struct toedev *tod;
230 #ifdef INVARIANTS
231 	struct inpcb *inp = tp->t_inpcb;
232 #endif
233 
234 	INP_WLOCK_ASSERT(inp);
235 	KASSERT(tp->t_state == TCPS_LISTEN,
236 	    ("%s: t_state %s", __func__, tcpstates[tp->t_state]));
237 
238 	mtx_lock(&toedev_lock);
239 	TAILQ_FOREACH(tod, &toedev_list, link)
240 	    tod->tod_listen_stop(tod, tp);
241 	mtx_unlock(&toedev_lock);
242 }
243 
244 /*
245  * Fill up a freshly allocated toedev struct with reasonable defaults.
246  */
247 void
248 init_toedev(struct toedev *tod)
249 {
250 
251 	tod->tod_softc = NULL;
252 
253 	/*
254 	 * Provide no-op defaults so that the kernel can call any toedev
255 	 * function without having to check whether the TOE driver supplied one
256 	 * or not.
257 	 */
258 	tod->tod_connect = toedev_connect;
259 	tod->tod_listen_start = toedev_listen_start;
260 	tod->tod_listen_stop = toedev_listen_stop;
261 	tod->tod_input = toedev_input;
262 	tod->tod_rcvd = toedev_rcvd;
263 	tod->tod_output = toedev_output;
264 	tod->tod_send_rst = toedev_output;
265 	tod->tod_send_fin = toedev_output;
266 	tod->tod_pcb_detach = toedev_pcb_detach;
267 	tod->tod_l2_update = toedev_l2_update;
268 	tod->tod_route_redirect = toedev_route_redirect;
269 	tod->tod_syncache_added = toedev_syncache_added;
270 	tod->tod_syncache_removed = toedev_syncache_removed;
271 	tod->tod_syncache_respond = toedev_syncache_respond;
272 	tod->tod_offload_socket = toedev_offload_socket;
273 	tod->tod_ctloutput = toedev_ctloutput;
274 }
275 
276 /*
277  * Register an active TOE device with the system.  This allows it to receive
278  * notifications from the kernel.
279  */
280 int
281 register_toedev(struct toedev *tod)
282 {
283 	struct toedev *t;
284 
285 	mtx_lock(&toedev_lock);
286 	TAILQ_FOREACH(t, &toedev_list, link) {
287 		if (t == tod) {
288 			mtx_unlock(&toedev_lock);
289 			return (EEXIST);
290 		}
291 	}
292 
293 	TAILQ_INSERT_TAIL(&toedev_list, tod, link);
294 	registered_toedevs++;
295 	mtx_unlock(&toedev_lock);
296 
297 	inp_apply_all(toe_listen_start, tod);
298 
299 	return (0);
300 }
301 
302 /*
303  * Remove the TOE device from the global list of active TOE devices.  It is the
304  * caller's responsibility to ensure that the TOE device is quiesced prior to
305  * this call.
306  */
307 int
308 unregister_toedev(struct toedev *tod)
309 {
310 	struct toedev *t, *t2;
311 	int rc = ENODEV;
312 
313 	mtx_lock(&toedev_lock);
314 	TAILQ_FOREACH_SAFE(t, &toedev_list, link, t2) {
315 		if (t == tod) {
316 			TAILQ_REMOVE(&toedev_list, tod, link);
317 			registered_toedevs--;
318 			rc = 0;
319 			break;
320 		}
321 	}
322 	KASSERT(registered_toedevs >= 0,
323 	    ("%s: registered_toedevs (%d) < 0", __func__, registered_toedevs));
324 	mtx_unlock(&toedev_lock);
325 	return (rc);
326 }
327 
328 void
329 toe_syncache_add(struct in_conninfo *inc, struct tcpopt *to, struct tcphdr *th,
330     struct inpcb *inp, void *tod, void *todctx)
331 {
332 	struct socket *lso = inp->inp_socket;
333 
334 	INP_WLOCK_ASSERT(inp);
335 
336 	syncache_add(inc, to, th, inp, &lso, NULL, tod, todctx);
337 }
338 
339 int
340 toe_syncache_expand(struct in_conninfo *inc, struct tcpopt *to,
341     struct tcphdr *th, struct socket **lsop)
342 {
343 
344 	INP_INFO_RLOCK_ASSERT(&V_tcbinfo);
345 
346 	return (syncache_expand(inc, to, th, lsop, NULL));
347 }
348 
349 /*
350  * General purpose check to see if a 4-tuple is in use by the kernel.  If a TCP
351  * header (presumably for an incoming SYN) is also provided, an existing 4-tuple
352  * in TIME_WAIT may be assassinated freeing it up for re-use.
353  *
354  * Note that the TCP header must have been run through tcp_fields_to_host() or
355  * equivalent.
356  */
357 int
358 toe_4tuple_check(struct in_conninfo *inc, struct tcphdr *th, struct ifnet *ifp)
359 {
360 	struct inpcb *inp;
361 
362 	if (inc->inc_flags & INC_ISIPV6) {
363 		inp = in6_pcblookup(&V_tcbinfo, &inc->inc6_faddr,
364 		    inc->inc_fport, &inc->inc6_laddr, inc->inc_lport,
365 		    INPLOOKUP_WLOCKPCB, ifp);
366 	} else {
367 		inp = in_pcblookup(&V_tcbinfo, inc->inc_faddr, inc->inc_fport,
368 		    inc->inc_laddr, inc->inc_lport, INPLOOKUP_WLOCKPCB, ifp);
369 	}
370 	if (inp != NULL) {
371 		INP_WLOCK_ASSERT(inp);
372 
373 		if ((inp->inp_flags & INP_TIMEWAIT) && th != NULL) {
374 
375 			INP_INFO_RLOCK_ASSERT(&V_tcbinfo); /* for twcheck */
376 			if (!tcp_twcheck(inp, NULL, th, NULL, 0))
377 				return (EADDRINUSE);
378 		} else {
379 			INP_WUNLOCK(inp);
380 			return (EADDRINUSE);
381 		}
382 	}
383 
384 	return (0);
385 }
386 
387 static void
388 toe_lle_event(void *arg __unused, struct llentry *lle, int evt)
389 {
390 	struct toedev *tod;
391 	struct ifnet *ifp;
392 	struct sockaddr *sa;
393 	uint8_t *lladdr;
394 	uint16_t vtag;
395 	int family;
396 	struct sockaddr_in6 sin6;
397 
398 	LLE_WLOCK_ASSERT(lle);
399 
400 	ifp = lltable_get_ifp(lle->lle_tbl);
401 	family = lltable_get_af(lle->lle_tbl);
402 
403 	if (family != AF_INET && family != AF_INET6)
404 		return;
405 	/*
406 	 * Not interested if the interface's TOE capability is not enabled.
407 	 */
408 	if ((family == AF_INET && !(ifp->if_capenable & IFCAP_TOE4)) ||
409 	    (family == AF_INET6 && !(ifp->if_capenable & IFCAP_TOE6)))
410 		return;
411 
412 	tod = TOEDEV(ifp);
413 	if (tod == NULL)
414 		return;
415 
416 	sa = (struct sockaddr *)&sin6;
417 	lltable_fill_sa_entry(lle, sa);
418 
419 	vtag = 0xfff;
420 	if (evt != LLENTRY_RESOLVED) {
421 
422 		/*
423 		 * LLENTRY_TIMEDOUT, LLENTRY_DELETED, LLENTRY_EXPIRED all mean
424 		 * this entry is going to be deleted.
425 		 */
426 
427 		lladdr = NULL;
428 	} else {
429 
430 		KASSERT(lle->la_flags & LLE_VALID,
431 		    ("%s: %p resolved but not valid?", __func__, lle));
432 
433 		lladdr = (uint8_t *)lle->ll_addr;
434 #ifdef VLAN_TAG
435 		VLAN_TAG(ifp, &vtag);
436 #endif
437 	}
438 
439 	tod->tod_l2_update(tod, ifp, sa, lladdr, vtag);
440 }
441 
442 /*
443  * Returns 0 or EWOULDBLOCK on success (any other value is an error).  0 means
444  * lladdr and vtag are valid on return, EWOULDBLOCK means the TOE driver's
445  * tod_l2_update will be called later, when the entry is resolved or times out.
446  */
447 int
448 toe_l2_resolve(struct toedev *tod, struct ifnet *ifp, struct sockaddr *sa,
449     uint8_t *lladdr, uint16_t *vtag)
450 {
451 	int rc;
452 
453 	switch (sa->sa_family) {
454 #ifdef INET
455 	case AF_INET:
456 		rc = arpresolve(ifp, 0, NULL, sa, lladdr, NULL, NULL);
457 		break;
458 #endif
459 #ifdef INET6
460 	case AF_INET6:
461 		rc = nd6_resolve(ifp, 0, NULL, sa, lladdr, NULL, NULL);
462 		break;
463 #endif
464 	default:
465 		return (EPROTONOSUPPORT);
466 	}
467 
468 	if (rc == 0) {
469 #ifdef VLAN_TAG
470 		if (VLAN_TAG(ifp, vtag) != 0)
471 #endif
472 			*vtag = 0xfff;
473 	}
474 
475 	return (rc);
476 }
477 
478 void
479 toe_connect_failed(struct toedev *tod, struct inpcb *inp, int err)
480 {
481 
482 	INP_WLOCK_ASSERT(inp);
483 
484 	if (!(inp->inp_flags & INP_DROPPED)) {
485 		struct tcpcb *tp = intotcpcb(inp);
486 
487 		KASSERT(tp->t_flags & TF_TOE,
488 		    ("%s: tp %p not offloaded.", __func__, tp));
489 
490 		if (err == EAGAIN) {
491 
492 			/*
493 			 * Temporary failure during offload, take this PCB back.
494 			 * Detach from the TOE driver and do the rest of what
495 			 * TCP's pru_connect would have done if the connection
496 			 * wasn't offloaded.
497 			 */
498 
499 			tod->tod_pcb_detach(tod, tp);
500 			KASSERT(!(tp->t_flags & TF_TOE),
501 			    ("%s: tp %p still offloaded.", __func__, tp));
502 			tcp_timer_activate(tp, TT_KEEP, TP_KEEPINIT(tp));
503 			(void) tp->t_fb->tfb_tcp_output(tp);
504 		} else {
505 
506 			INP_INFO_RLOCK_ASSERT(&V_tcbinfo);
507 			tp = tcp_drop(tp, err);
508 			if (tp == NULL)
509 				INP_WLOCK(inp);	/* re-acquire */
510 		}
511 	}
512 	INP_WLOCK_ASSERT(inp);
513 }
514 
515 static int
516 toecore_load(void)
517 {
518 
519 	mtx_init(&toedev_lock, "toedev lock", NULL, MTX_DEF);
520 	TAILQ_INIT(&toedev_list);
521 
522 	listen_start_eh = EVENTHANDLER_REGISTER(tcp_offload_listen_start,
523 	    toe_listen_start_event, NULL, EVENTHANDLER_PRI_ANY);
524 	listen_stop_eh = EVENTHANDLER_REGISTER(tcp_offload_listen_stop,
525 	    toe_listen_stop_event, NULL, EVENTHANDLER_PRI_ANY);
526 	lle_event_eh = EVENTHANDLER_REGISTER(lle_event, toe_lle_event, NULL,
527 	    EVENTHANDLER_PRI_ANY);
528 
529 	return (0);
530 }
531 
532 static int
533 toecore_unload(void)
534 {
535 
536 	mtx_lock(&toedev_lock);
537 	if (!TAILQ_EMPTY(&toedev_list)) {
538 		mtx_unlock(&toedev_lock);
539 		return (EBUSY);
540 	}
541 
542 	EVENTHANDLER_DEREGISTER(tcp_offload_listen_start, listen_start_eh);
543 	EVENTHANDLER_DEREGISTER(tcp_offload_listen_stop, listen_stop_eh);
544 	EVENTHANDLER_DEREGISTER(lle_event, lle_event_eh);
545 
546 	mtx_unlock(&toedev_lock);
547 	mtx_destroy(&toedev_lock);
548 
549 	return (0);
550 }
551 
552 static int
553 toecore_mod_handler(module_t mod, int cmd, void *arg)
554 {
555 
556 	if (cmd == MOD_LOAD)
557 		return (toecore_load());
558 
559 	if (cmd == MOD_UNLOAD)
560 		return (toecore_unload());
561 
562 	return (EOPNOTSUPP);
563 }
564 
565 static moduledata_t mod_data= {
566 	"toecore",
567 	toecore_mod_handler,
568 	0
569 };
570 
571 MODULE_VERSION(toecore, 1);
572 DECLARE_MODULE(toecore, mod_data, SI_SUB_EXEC, SI_ORDER_ANY);
573