xref: /freebsd/sys/netgraph/ng_cisco.c (revision a0ee8cc6)
1 /*
2  * ng_cisco.c
3  */
4 
5 /*-
6  * Copyright (c) 1996-1999 Whistle Communications, Inc.
7  * All rights reserved.
8  *
9  * Subject to the following obligations and disclaimer of warranty, use and
10  * redistribution of this software, in source or object code forms, with or
11  * without modifications are expressly permitted by Whistle Communications;
12  * provided, however, that:
13  * 1. Any and all reproductions of the source or object code must include the
14  *    copyright notice above and the following disclaimer of warranties; and
15  * 2. No rights are granted, in any manner or form, to use Whistle
16  *    Communications, Inc. trademarks, including the mark "WHISTLE
17  *    COMMUNICATIONS" on advertising, endorsements, or otherwise except as
18  *    such appears in the above copyright notice or in the software.
19  *
20  * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
21  * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
22  * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
23  * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
24  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
25  * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
26  * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
27  * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
28  * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
29  * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
30  * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
31  * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
32  * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
33  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
34  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
35  * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
36  * OF SUCH DAMAGE.
37  *
38  * Author: Julian Elischer <julian@freebsd.org>
39  *
40  * $FreeBSD$
41  * $Whistle: ng_cisco.c,v 1.25 1999/11/01 09:24:51 julian Exp $
42  */
43 
44 #include <sys/param.h>
45 #include <sys/systm.h>
46 #include <sys/errno.h>
47 #include <sys/kernel.h>
48 #include <sys/socket.h>
49 #include <sys/malloc.h>
50 #include <sys/mbuf.h>
51 #include <sys/syslog.h>
52 
53 #include <net/if.h>
54 
55 #include <netinet/in.h>
56 #include <netinet/if_ether.h>
57 
58 #include <netgraph/ng_message.h>
59 #include <netgraph/netgraph.h>
60 #include <netgraph/ng_parse.h>
61 #include <netgraph/ng_cisco.h>
62 
63 #define	CISCO_MULTICAST		0x8f	/* Cisco multicast address */
64 #define	CISCO_UNICAST		0x0f	/* Cisco unicast address */
65 #define	CISCO_KEEPALIVE		0x8035	/* Cisco keepalive protocol */
66 #define	CISCO_ADDR_REQ		0	/* Cisco address request */
67 #define	CISCO_ADDR_REPLY	1	/* Cisco address reply */
68 #define	CISCO_KEEPALIVE_REQ	2	/* Cisco keepalive request */
69 
70 #define KEEPALIVE_SECS		10
71 
72 struct cisco_header {
73 	uint8_t  address;
74 	uint8_t  control;
75 	uint16_t protocol;
76 } __packed;
77 
78 #define	CISCO_HEADER_LEN	sizeof (struct cisco_header)
79 
80 struct cisco_packet {
81 	uint32_t type;
82 	uint32_t par1;
83 	uint32_t par2;
84 	uint16_t rel;
85 	uint16_t time0;
86 	uint16_t time1;
87 } __packed;
88 
89 #define	CISCO_PACKET_LEN (sizeof(struct cisco_packet))
90 
91 struct protoent {
92 	hook_p  hook;		/* the hook for this proto */
93 	uint16_t af;		/* address family, -1 = downstream */
94 };
95 
96 struct cisco_priv {
97 	uint32_t local_seq;
98 	uint32_t remote_seq;
99 	uint32_t seqRetries;	/* how many times we've been here throwing out
100 				 * the same sequence number without ack */
101 	node_p  node;
102 	struct callout handle;
103 	struct protoent downstream;
104 	struct protoent inet;		/* IP information */
105 	struct in_addr localip;
106 	struct in_addr localmask;
107 	struct protoent inet6;		/* IPv6 information */
108 	struct protoent atalk;		/* AppleTalk information */
109 	struct protoent ipx;		/* IPX information */
110 };
111 typedef struct cisco_priv *sc_p;
112 
113 /* Netgraph methods */
114 static ng_constructor_t		cisco_constructor;
115 static ng_rcvmsg_t		cisco_rcvmsg;
116 static ng_shutdown_t		cisco_shutdown;
117 static ng_newhook_t		cisco_newhook;
118 static ng_rcvdata_t		cisco_rcvdata;
119 static ng_disconnect_t		cisco_disconnect;
120 
121 /* Other functions */
122 static int	cisco_input(sc_p sc, item_p item);
123 static void	cisco_keepalive(node_p node, hook_p hook, void *arg1, int arg2);
124 static int	cisco_send(sc_p sc, int type, long par1, long par2);
125 static void	cisco_notify(sc_p sc, uint32_t cmd);
126 
127 /* Parse type for struct ng_cisco_ipaddr */
128 static const struct ng_parse_struct_field ng_cisco_ipaddr_type_fields[]
129 	= NG_CISCO_IPADDR_TYPE_INFO;
130 static const struct ng_parse_type ng_cisco_ipaddr_type = {
131 	&ng_parse_struct_type,
132 	&ng_cisco_ipaddr_type_fields
133 };
134 
135 /* Parse type for struct ng_async_stat */
136 static const struct ng_parse_struct_field ng_cisco_stats_type_fields[]
137 	= NG_CISCO_STATS_TYPE_INFO;
138 static const struct ng_parse_type ng_cisco_stats_type = {
139 	&ng_parse_struct_type,
140 	&ng_cisco_stats_type_fields
141 };
142 
143 /* List of commands and how to convert arguments to/from ASCII */
144 static const struct ng_cmdlist ng_cisco_cmdlist[] = {
145 	{
146 	  NGM_CISCO_COOKIE,
147 	  NGM_CISCO_SET_IPADDR,
148 	  "setipaddr",
149 	  &ng_cisco_ipaddr_type,
150 	  NULL
151 	},
152 	{
153 	  NGM_CISCO_COOKIE,
154 	  NGM_CISCO_GET_IPADDR,
155 	  "getipaddr",
156 	  NULL,
157 	  &ng_cisco_ipaddr_type
158 	},
159 	{
160 	  NGM_CISCO_COOKIE,
161 	  NGM_CISCO_GET_STATUS,
162 	  "getstats",
163 	  NULL,
164 	  &ng_cisco_stats_type
165 	},
166 	{ 0 }
167 };
168 
169 /* Node type */
170 static struct ng_type typestruct = {
171 	.version =	NG_ABI_VERSION,
172 	.name =		NG_CISCO_NODE_TYPE,
173 	.constructor =	cisco_constructor,
174 	.rcvmsg =	cisco_rcvmsg,
175 	.shutdown =	cisco_shutdown,
176 	.newhook =	cisco_newhook,
177 	.rcvdata =	cisco_rcvdata,
178 	.disconnect =	cisco_disconnect,
179 	.cmdlist =	ng_cisco_cmdlist,
180 };
181 NETGRAPH_INIT(cisco, &typestruct);
182 
183 /*
184  * Node constructor
185  */
186 static int
187 cisco_constructor(node_p node)
188 {
189 	sc_p sc;
190 
191 	sc = malloc(sizeof(*sc), M_NETGRAPH, M_WAITOK | M_ZERO);
192 
193 	ng_callout_init(&sc->handle);
194 	NG_NODE_SET_PRIVATE(node, sc);
195 	sc->node = node;
196 
197 	/* Initialise the varous protocol hook holders */
198 	sc->downstream.af = 0xffff;
199 	sc->inet.af = AF_INET;
200 	sc->inet6.af = AF_INET6;
201 	sc->atalk.af = AF_APPLETALK;
202 	sc->ipx.af = AF_IPX;
203 	return (0);
204 }
205 
206 /*
207  * Check new hook
208  */
209 static int
210 cisco_newhook(node_p node, hook_p hook, const char *name)
211 {
212 	const sc_p sc = NG_NODE_PRIVATE(node);
213 
214 	if (strcmp(name, NG_CISCO_HOOK_DOWNSTREAM) == 0) {
215 		sc->downstream.hook = hook;
216 		NG_HOOK_SET_PRIVATE(hook, &sc->downstream);
217 
218 		/* Start keepalives */
219 		ng_callout(&sc->handle, node, NULL, (hz * KEEPALIVE_SECS),
220 		    &cisco_keepalive, (void *)sc, 0);
221 	} else if (strcmp(name, NG_CISCO_HOOK_INET) == 0) {
222 		sc->inet.hook = hook;
223 		NG_HOOK_SET_PRIVATE(hook, &sc->inet);
224 	} else if (strcmp(name, NG_CISCO_HOOK_INET6) == 0) {
225 		sc->inet6.hook = hook;
226 		NG_HOOK_SET_PRIVATE(hook, &sc->inet6);
227 	} else if (strcmp(name, NG_CISCO_HOOK_APPLETALK) == 0) {
228 		sc->atalk.hook = hook;
229 		NG_HOOK_SET_PRIVATE(hook, &sc->atalk);
230 	} else if (strcmp(name, NG_CISCO_HOOK_IPX) == 0) {
231 		sc->ipx.hook = hook;
232 		NG_HOOK_SET_PRIVATE(hook, &sc->ipx);
233 	} else if (strcmp(name, NG_CISCO_HOOK_DEBUG) == 0) {
234 		NG_HOOK_SET_PRIVATE(hook, NULL);	/* unimplemented */
235 	} else
236 		return (EINVAL);
237 	return 0;
238 }
239 
240 /*
241  * Receive control message.
242  */
243 static int
244 cisco_rcvmsg(node_p node, item_p item, hook_p lasthook)
245 {
246 	struct ng_mesg *msg;
247 	const sc_p sc = NG_NODE_PRIVATE(node);
248 	struct ng_mesg *resp = NULL;
249 	int error = 0;
250 
251 	NGI_GET_MSG(item, msg);
252 	switch (msg->header.typecookie) {
253 	case NGM_GENERIC_COOKIE:
254 		switch (msg->header.cmd) {
255 		case NGM_TEXT_STATUS:
256 		    {
257 			char *arg;
258 			int pos;
259 
260 			NG_MKRESPONSE(resp, msg, NG_TEXTRESPONSE, M_NOWAIT);
261 			if (resp == NULL) {
262 				error = ENOMEM;
263 				break;
264 			}
265 			arg = (char *) resp->data;
266 			pos = sprintf(arg,
267 			  "keepalive period: %d sec; ", KEEPALIVE_SECS);
268 			pos += sprintf(arg + pos,
269 			  "unacknowledged keepalives: %d", sc->seqRetries);
270 			resp->header.arglen = pos + 1;
271 			break;
272 		    }
273 		default:
274 			error = EINVAL;
275 			break;
276 		}
277 		break;
278 	case NGM_CISCO_COOKIE:
279 		switch (msg->header.cmd) {
280 		case NGM_CISCO_GET_IPADDR:	/* could be a late reply! */
281 			if ((msg->header.flags & NGF_RESP) == 0) {
282 				struct in_addr *ips;
283 
284 				NG_MKRESPONSE(resp, msg,
285 				    2 * sizeof(*ips), M_NOWAIT);
286 				if (!resp) {
287 					error = ENOMEM;
288 					break;
289 				}
290 				ips = (struct in_addr *) resp->data;
291 				ips[0] = sc->localip;
292 				ips[1] = sc->localmask;
293 				break;
294 			}
295 			/* FALLTHROUGH */	/* ...if it's a reply */
296 		case NGM_CISCO_SET_IPADDR:
297 		    {
298 			struct in_addr *const ips = (struct in_addr *)msg->data;
299 
300 			if (msg->header.arglen < 2 * sizeof(*ips)) {
301 				error = EINVAL;
302 				break;
303 			}
304 			sc->localip = ips[0];
305 			sc->localmask = ips[1];
306 			break;
307 		    }
308 		case NGM_CISCO_GET_STATUS:
309 		    {
310 			struct ng_cisco_stats *stat;
311 
312 			NG_MKRESPONSE(resp, msg, sizeof(*stat), M_NOWAIT);
313 			if (!resp) {
314 				error = ENOMEM;
315 				break;
316 			}
317 			stat = (struct ng_cisco_stats *)resp->data;
318 			stat->seqRetries = sc->seqRetries;
319 			stat->keepAlivePeriod = KEEPALIVE_SECS;
320 			break;
321 		    }
322 		default:
323 			error = EINVAL;
324 			break;
325 		}
326 		break;
327 	default:
328 		error = EINVAL;
329 		break;
330 	}
331 	NG_RESPOND_MSG(error, node, item, resp);
332 	NG_FREE_MSG(msg);
333 	return (error);
334 }
335 
336 /*
337  * Receive data
338  */
339 static int
340 cisco_rcvdata(hook_p hook, item_p item)
341 {
342 	const sc_p sc = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
343 	struct protoent *pep;
344 	struct cisco_header *h;
345 	struct mbuf *m;
346 	int error = 0;
347 
348 	if ((pep = NG_HOOK_PRIVATE(hook)) == NULL)
349 		goto out;
350 
351 	/* If it came from our downlink, deal with it separately */
352 	if (pep->af == 0xffff)
353 		return (cisco_input(sc, item));
354 
355 	/* OK so it came from a protocol, heading out. Prepend general data
356 	   packet header. For now, IP,IPX only  */
357 	NGI_GET_M(item, m);
358 	M_PREPEND(m, CISCO_HEADER_LEN, M_NOWAIT);
359 	if (!m) {
360 		error = ENOBUFS;
361 		goto out;
362 	}
363 	NGI_M(item) = m;
364 	h = mtod(m, struct cisco_header *);
365 	h->address = CISCO_UNICAST;
366 	h->control = 0;
367 
368 	switch (pep->af) {
369 	case AF_INET:		/* Internet Protocol */
370 		h->protocol = htons(ETHERTYPE_IP);
371 		break;
372 	case AF_INET6:
373 		h->protocol = htons(ETHERTYPE_IPV6);
374 		break;
375 	case AF_APPLETALK:	/* AppleTalk Protocol */
376 		h->protocol = htons(ETHERTYPE_AT);
377 		break;
378 	case AF_IPX:		/* Novell IPX Protocol */
379 		h->protocol = htons(ETHERTYPE_IPX);
380 		break;
381 	default:
382 		error = EAFNOSUPPORT;
383 		goto out;
384 	}
385 
386 	/* Send it */
387 	NG_FWD_NEW_DATA(error, item,  sc->downstream.hook, m);
388 	return (error);
389 
390 out:
391 	NG_FREE_ITEM(item);
392 	return (error);
393 }
394 
395 /*
396  * Shutdown node
397  */
398 static int
399 cisco_shutdown(node_p node)
400 {
401 	const sc_p sc = NG_NODE_PRIVATE(node);
402 
403 	NG_NODE_SET_PRIVATE(node, NULL);
404 	NG_NODE_UNREF(sc->node);
405 	free(sc, M_NETGRAPH);
406 	return (0);
407 }
408 
409 /*
410  * Disconnection of a hook
411  *
412  * For this type, removal of the last link destroys the node
413  */
414 static int
415 cisco_disconnect(hook_p hook)
416 {
417 	const sc_p sc = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
418 	struct protoent *pep;
419 
420 	/* Check it's not the debug hook */
421 	if ((pep = NG_HOOK_PRIVATE(hook))) {
422 		pep->hook = NULL;
423 		if (pep->af == 0xffff)
424 			/* If it is the downstream hook, stop the timers */
425 			ng_uncallout(&sc->handle, NG_HOOK_NODE(hook));
426 	}
427 
428 	/* If no more hooks, remove the node */
429 	if ((NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0)
430 	&& (NG_NODE_IS_VALID(NG_HOOK_NODE(hook))))
431 		ng_rmnode_self(NG_HOOK_NODE(hook));
432 	return (0);
433 }
434 
435 /*
436  * Receive data
437  */
438 static int
439 cisco_input(sc_p sc, item_p item)
440 {
441 	const struct cisco_header *h;
442 	struct cisco_header hdrbuf;
443 	struct protoent *pep;
444 	struct mbuf *m;
445 	int error = 0;
446 
447 	/* Get data */
448 	m = NGI_M(item);
449 
450 	/* Sanity check header length */
451 	if (m->m_pkthdr.len < sizeof(*h)) {
452 		error = EINVAL;
453 		goto drop;
454 	}
455 
456 	/* Get cisco header */
457 	if (m->m_len >= sizeof(*h))			/* the common case */
458 		h = mtod(m, const struct cisco_header *);
459 	else {
460 		m_copydata(m, 0, sizeof(*h), (caddr_t)&hdrbuf);
461 		h = &hdrbuf;
462 	}
463 	m_adj(m, sizeof(*h));
464 
465 	/* Check header address */
466 	switch (h->address) {
467 	default:		/* Invalid Cisco packet. */
468 		goto drop;
469 	case CISCO_UNICAST:
470 	case CISCO_MULTICAST:
471 		/* Don't check the control field here (RFC 1547). */
472 		switch (ntohs(h->protocol)) {
473 		default:
474 			goto drop;
475 		case CISCO_KEEPALIVE:
476 		    {
477 			const struct cisco_packet *p;
478 			struct cisco_packet pktbuf;
479 
480 			/* Sanity check packet length */
481 			if (m->m_pkthdr.len < sizeof(*p)) {
482 				error = EINVAL;
483 				goto drop;
484 			}
485 
486 			/* Get cisco packet */
487 			if (m->m_len >= sizeof(*p))	/* the common case */
488 				p = mtod(m, const struct cisco_packet *);
489 			else {
490 				m_copydata(m, 0, sizeof(*p), (caddr_t)&pktbuf);
491 				p = &pktbuf;
492 			}
493 
494 			/* Check packet type */
495 			switch (ntohl(p->type)) {
496 			default:
497 				log(LOG_WARNING,
498 				    "cisco: unknown cisco packet type: 0x%lx\n",
499 				       (long)ntohl(p->type));
500 				break;
501 			case CISCO_ADDR_REPLY:
502 				/* Reply on address request, ignore */
503 				break;
504 			case CISCO_KEEPALIVE_REQ:
505 				sc->remote_seq = ntohl(p->par1);
506 				if (sc->local_seq == ntohl(p->par2)) {
507 					sc->local_seq++;
508 					if (sc->seqRetries > 1)
509 						cisco_notify(sc, NGM_LINK_IS_UP);
510 					sc->seqRetries = 0;
511 				}
512 				break;
513 			case CISCO_ADDR_REQ:
514 			    {
515 				struct ng_mesg *msg;
516 				int dummy_error = 0;
517 
518 				/* Ask inet peer for IP address information */
519 				if (sc->inet.hook == NULL)
520 					goto nomsg;
521 				NG_MKMESSAGE(msg, NGM_CISCO_COOKIE,
522 				    NGM_CISCO_GET_IPADDR, 0, M_NOWAIT);
523 				if (msg == NULL)
524 					goto nomsg;
525 				NG_SEND_MSG_HOOK(dummy_error,
526 				    sc->node, msg, sc->inet.hook, 0);
527 		/*
528 		 * XXX Now maybe we should set a flag telling
529 		 * our receiver to send this message when the response comes in
530 		 * instead of now when the data may be bad.
531 		 */
532 		nomsg:
533 				/* Send reply to peer device */
534 				error = cisco_send(sc, CISCO_ADDR_REPLY,
535 					    ntohl(sc->localip.s_addr),
536 					    ntohl(sc->localmask.s_addr));
537 				break;
538 			    }
539 			}
540 			goto drop;
541 		    }
542 		case ETHERTYPE_IP:
543 			pep = &sc->inet;
544 			break;
545 		case ETHERTYPE_IPV6:
546 			pep = &sc->inet6;
547 			break;
548 		case ETHERTYPE_AT:
549 			pep = &sc->atalk;
550 			break;
551 		case ETHERTYPE_IPX:
552 			pep = &sc->ipx;
553 			break;
554 		}
555 		break;
556 	}
557 
558 	/* Drop if payload is empty */
559 	if (m->m_pkthdr.len == 0) {
560 		error = EINVAL;
561 		goto drop;
562 	}
563 
564 	/* Send it on */
565 	if (pep->hook == NULL)
566 		goto drop;
567 	NG_FWD_NEW_DATA(error, item, pep->hook, m);
568 	return (error);
569 
570 drop:
571 	NG_FREE_ITEM(item);
572 	return (error);
573 }
574 
575 
576 /*
577  * Send keepalive packets, every 10 seconds.
578  */
579 static void
580 cisco_keepalive(node_p node, hook_p hook, void *arg1, int arg2)
581 {
582 	const sc_p sc = arg1;
583 
584 	cisco_send(sc, CISCO_KEEPALIVE_REQ, sc->local_seq, sc->remote_seq);
585 	if (sc->seqRetries++ > 1)
586 		cisco_notify(sc, NGM_LINK_IS_DOWN);
587 	ng_callout(&sc->handle, node, NULL, (hz * KEEPALIVE_SECS),
588 	    &cisco_keepalive, (void *)sc, 0);
589 }
590 
591 /*
592  * Send Cisco keepalive packet.
593  */
594 static int
595 cisco_send(sc_p sc, int type, long par1, long par2)
596 {
597 	struct cisco_header *h;
598 	struct cisco_packet *ch;
599 	struct mbuf *m;
600 	struct timeval time;
601 	uint32_t t;
602 	int     error = 0;
603 
604 	getmicrouptime(&time);
605 
606 	MGETHDR(m, M_NOWAIT, MT_DATA);
607 	if (!m)
608 		return (ENOBUFS);
609 
610 	t = time.tv_sec * 1000 + time.tv_usec / 1000;
611 	m->m_pkthdr.len = m->m_len = CISCO_HEADER_LEN + CISCO_PACKET_LEN;
612 	m->m_pkthdr.rcvif = 0;
613 
614 	h = mtod(m, struct cisco_header *);
615 	h->address = CISCO_MULTICAST;
616 	h->control = 0;
617 	h->protocol = htons(CISCO_KEEPALIVE);
618 
619 	ch = (struct cisco_packet *) (h + 1);
620 	ch->type = htonl(type);
621 	ch->par1 = htonl(par1);
622 	ch->par2 = htonl(par2);
623 	ch->rel = -1;
624 	ch->time0 = htons((uint16_t) (t >> 16));
625 	ch->time1 = htons((uint16_t) t);
626 
627 	NG_SEND_DATA_ONLY(error, sc->downstream.hook, m);
628 	return (error);
629 }
630 
631 /*
632  * Send linkstate to upstream node.
633  */
634 static void
635 cisco_notify(sc_p sc, uint32_t cmd)
636 {
637 	struct ng_mesg *msg;
638 	int dummy_error = 0;
639 
640 	if (sc->inet.hook == NULL) /* nothing to notify */
641 		return;
642 
643 	NG_MKMESSAGE(msg, NGM_FLOW_COOKIE, cmd, 0, M_NOWAIT);
644 	if (msg != NULL)
645 		NG_SEND_MSG_HOOK(dummy_error, sc->node, msg, sc->inet.hook, 0);
646 }
647