xref: /freebsd/sys/netgraph/ng_cisco.c (revision 77a0943ded95b9e6438f7db70c4a28e4d93946d4)
1 
2 /*
3  * ng_cisco.c
4  *
5  * Copyright (c) 1996-1999 Whistle Communications, Inc.
6  * All rights reserved.
7  *
8  * Subject to the following obligations and disclaimer of warranty, use and
9  * redistribution of this software, in source or object code forms, with or
10  * without modifications are expressly permitted by Whistle Communications;
11  * provided, however, that:
12  * 1. Any and all reproductions of the source or object code must include the
13  *    copyright notice above and the following disclaimer of warranties; and
14  * 2. No rights are granted, in any manner or form, to use Whistle
15  *    Communications, Inc. trademarks, including the mark "WHISTLE
16  *    COMMUNICATIONS" on advertising, endorsements, or otherwise except as
17  *    such appears in the above copyright notice or in the software.
18  *
19  * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
20  * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
21  * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
22  * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
23  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
24  * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
25  * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
26  * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
27  * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
28  * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
29  * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
30  * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
31  * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
32  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
33  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
34  * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
35  * OF SUCH DAMAGE.
36  *
37  * Author: Julian Elischer <julian@freebsd.org>
38  *
39  * $FreeBSD$
40  * $Whistle: ng_cisco.c,v 1.25 1999/11/01 09:24:51 julian Exp $
41  */
42 
43 #include <sys/param.h>
44 #include <sys/systm.h>
45 #include <sys/errno.h>
46 #include <sys/kernel.h>
47 #include <sys/socket.h>
48 #include <sys/malloc.h>
49 #include <sys/mbuf.h>
50 #include <sys/syslog.h>
51 
52 #include <net/if.h>
53 
54 #include <netinet/in.h>
55 #include <netinet/if_ether.h>
56 
57 #include <netatalk/at.h>
58 
59 #include <netipx/ipx.h>
60 #include <netipx/ipx_if.h>
61 
62 #include <netgraph/ng_message.h>
63 #include <netgraph/netgraph.h>
64 #include <netgraph/ng_parse.h>
65 #include <netgraph/ng_cisco.h>
66 
67 #define CISCO_MULTICAST         0x8f	/* Cisco multicast address */
68 #define CISCO_UNICAST           0x0f	/* Cisco unicast address */
69 #define CISCO_KEEPALIVE         0x8035	/* Cisco keepalive protocol */
70 #define CISCO_ADDR_REQ          0	/* Cisco address request */
71 #define CISCO_ADDR_REPLY        1	/* Cisco address reply */
72 #define CISCO_KEEPALIVE_REQ     2	/* Cisco keepalive request */
73 
74 #define KEEPALIVE_SECS		10
75 
76 struct cisco_header {
77 	u_char  address;
78 	u_char  control;
79 	u_short protocol;
80 };
81 
82 #define CISCO_HEADER_LEN          sizeof (struct cisco_header)
83 
84 struct cisco_packet {
85 	u_long  type;
86 	u_long  par1;
87 	u_long  par2;
88 	u_short rel;
89 	u_short time0;
90 	u_short time1;
91 };
92 
93 #define CISCO_PACKET_LEN (sizeof(struct cisco_packet))
94 
95 struct protoent {
96 	hook_p  hook;		/* the hook for this proto */
97 	u_short af;		/* address family, -1 = downstream */
98 };
99 
100 struct cisco_priv {
101 	u_long  local_seq;
102 	u_long  remote_seq;
103 	u_long  seqRetries;	/* how many times we've been here throwing out
104 				 * the same sequence number without ack */
105 	node_p  node;
106 	struct callout_handle handle;
107 	struct protoent downstream;
108 	struct protoent inet;		/* IP information */
109 	struct in_addr localip;
110 	struct in_addr localmask;
111 	struct protoent inet6;		/* IPv6 information */
112 	struct protoent atalk;		/* AppleTalk information */
113 	struct protoent ipx;		/* IPX information */
114 };
115 typedef struct cisco_priv *sc_p;
116 
117 /* Netgraph methods */
118 static ng_constructor_t		cisco_constructor;
119 static ng_rcvmsg_t		cisco_rcvmsg;
120 static ng_shutdown_t		cisco_rmnode;
121 static ng_newhook_t		cisco_newhook;
122 static ng_rcvdata_t		cisco_rcvdata;
123 static ng_disconnect_t		cisco_disconnect;
124 
125 /* Other functions */
126 static int	cisco_input(sc_p sc, struct mbuf *m, meta_p meta);
127 static void	cisco_keepalive(void *arg);
128 static int	cisco_send(sc_p sc, int type, long par1, long par2);
129 
130 /* Parse type for struct ng_cisco_ipaddr */
131 static const struct ng_parse_struct_info
132 	ng_cisco_ipaddr_type_info = NG_CISCO_IPADDR_TYPE_INFO;
133 static const struct ng_parse_type ng_cisco_ipaddr_type = {
134 	&ng_parse_struct_type,
135 	&ng_cisco_ipaddr_type_info
136 };
137 
138 /* Parse type for struct ng_async_stat */
139 static const struct ng_parse_struct_info
140 	ng_cisco_stats_type_info = NG_CISCO_STATS_TYPE_INFO;
141 static const struct ng_parse_type ng_cisco_stats_type = {
142 	&ng_parse_struct_type,
143 	&ng_cisco_stats_type_info,
144 };
145 
146 /* List of commands and how to convert arguments to/from ASCII */
147 static const struct ng_cmdlist ng_cisco_cmdlist[] = {
148 	{
149 	  NGM_CISCO_COOKIE,
150 	  NGM_CISCO_SET_IPADDR,
151 	  "setipaddr",
152 	  &ng_cisco_ipaddr_type,
153 	  NULL
154 	},
155 	{
156 	  NGM_CISCO_COOKIE,
157 	  NGM_CISCO_GET_IPADDR,
158 	  "getipaddr",
159 	  NULL,
160 	  &ng_cisco_ipaddr_type
161 	},
162 	{
163 	  NGM_CISCO_COOKIE,
164 	  NGM_CISCO_GET_STATUS,
165 	  "getstats",
166 	  NULL,
167 	  &ng_cisco_stats_type
168 	},
169 	{ 0 }
170 };
171 
172 /* Node type */
173 static struct ng_type typestruct = {
174 	NG_VERSION,
175 	NG_CISCO_NODE_TYPE,
176 	NULL,
177 	cisco_constructor,
178 	cisco_rcvmsg,
179 	cisco_rmnode,
180 	cisco_newhook,
181 	NULL,
182 	NULL,
183 	cisco_rcvdata,
184 	cisco_rcvdata,
185 	cisco_disconnect,
186 	ng_cisco_cmdlist
187 };
188 NETGRAPH_INIT(cisco, &typestruct);
189 
190 /*
191  * Node constructor
192  */
193 static int
194 cisco_constructor(node_p *nodep)
195 {
196 	sc_p sc;
197 	int error = 0;
198 
199 	MALLOC(sc, sc_p, sizeof(*sc), M_NETGRAPH, M_NOWAIT | M_ZERO);
200 	if (sc == NULL)
201 		return (ENOMEM);
202 
203 	callout_handle_init(&sc->handle);
204 	if ((error = ng_make_node_common(&typestruct, nodep))) {
205 		FREE(sc, M_NETGRAPH);
206 		return (error);
207 	}
208 	(*nodep)->private = sc;
209 	sc->node = *nodep;
210 
211 	/* Initialise the varous protocol hook holders */
212 	sc->downstream.af = 0xffff;
213 	sc->inet.af = AF_INET;
214 	sc->inet6.af = AF_INET6;
215 	sc->atalk.af = AF_APPLETALK;
216 	sc->ipx.af = AF_IPX;
217 	return (0);
218 }
219 
220 /*
221  * Check new hook
222  */
223 static int
224 cisco_newhook(node_p node, hook_p hook, const char *name)
225 {
226 	const sc_p sc = node->private;
227 
228 	if (strcmp(name, NG_CISCO_HOOK_DOWNSTREAM) == 0) {
229 		sc->downstream.hook = hook;
230 		hook->private = &sc->downstream;
231 
232 		/* Start keepalives */
233 		sc->handle = timeout(cisco_keepalive, sc, hz * KEEPALIVE_SECS);
234 	} else if (strcmp(name, NG_CISCO_HOOK_INET) == 0) {
235 		sc->inet.hook = hook;
236 		hook->private = &sc->inet;
237 	} else if (strcmp(name, NG_CISCO_HOOK_APPLETALK) == 0) {
238 		sc->atalk.hook = hook;
239 		hook->private = &sc->atalk;
240 	} else if (strcmp(name, NG_CISCO_HOOK_IPX) == 0) {
241 		sc->ipx.hook = hook;
242 		hook->private = &sc->ipx;
243 	} else if (strcmp(name, NG_CISCO_HOOK_DEBUG) == 0) {
244 		hook->private = NULL;	/* unimplemented */
245 	} else
246 		return (EINVAL);
247 	return 0;
248 }
249 
250 /*
251  * Receive control message.
252  */
253 static int
254 cisco_rcvmsg(node_p node, struct ng_mesg *msg,
255 	const char *retaddr, struct ng_mesg **rptr, hook_p lasthook)
256 {
257 	const sc_p sc = node->private;
258 	struct ng_mesg *resp = NULL;
259 	int error = 0;
260 
261 	switch (msg->header.typecookie) {
262 	case NGM_GENERIC_COOKIE:
263 		switch (msg->header.cmd) {
264 		case NGM_TEXT_STATUS:
265 		    {
266 			char *arg;
267 			int pos;
268 
269 			NG_MKRESPONSE(resp, msg, sizeof(struct ng_mesg)
270 			    + NG_TEXTRESPONSE, M_NOWAIT);
271 			if (resp == NULL) {
272 				error = ENOMEM;
273 				break;
274 			}
275 			arg = (char *) resp->data;
276 			pos = sprintf(arg,
277 			  "keepalive period: %d sec; ", KEEPALIVE_SECS);
278 			pos += sprintf(arg + pos,
279 			  "unacknowledged keepalives: %ld", sc->seqRetries);
280 			resp->header.arglen = pos + 1;
281 			break;
282 		    }
283 		default:
284 			error = EINVAL;
285 			break;
286 		}
287 		break;
288 	case NGM_CISCO_COOKIE:
289 		switch (msg->header.cmd) {
290 		case NGM_CISCO_GET_IPADDR:	/* could be a late reply! */
291 			if ((msg->header.flags & NGF_RESP) == 0) {
292 				struct in_addr *ips;
293 
294 				NG_MKRESPONSE(resp, msg,
295 				    2 * sizeof(*ips), M_NOWAIT);
296 				if (!resp) {
297 					error = ENOMEM;
298 					break;
299 				}
300 				ips = (struct in_addr *) resp->data;
301 				ips[0] = sc->localip;
302 				ips[1] = sc->localmask;
303 				break;
304 			}
305 			/* FALLTHROUGH */	/* ...if it's a reply */
306 		case NGM_CISCO_SET_IPADDR:
307 		    {
308 			struct in_addr *const ips = (struct in_addr *)msg->data;
309 
310 			if (msg->header.arglen < 2 * sizeof(*ips)) {
311 				error = EINVAL;
312 				break;
313 			}
314 			sc->localip = ips[0];
315 			sc->localmask = ips[1];
316 			break;
317 		    }
318 		case NGM_CISCO_GET_STATUS:
319 		    {
320 			struct ng_cisco_stats *stat;
321 
322 			NG_MKRESPONSE(resp, msg, sizeof(*stat), M_NOWAIT);
323 			if (!resp) {
324 				error = ENOMEM;
325 				break;
326 			}
327 			stat = (struct ng_cisco_stats *)resp->data;
328 			stat->seqRetries = sc->seqRetries;
329 			stat->keepAlivePeriod = KEEPALIVE_SECS;
330 			break;
331 		    }
332 		default:
333 			error = EINVAL;
334 			break;
335 		}
336 		break;
337 	default:
338 		error = EINVAL;
339 		break;
340 	}
341 	if (rptr)
342 		*rptr = resp;
343 	else if (resp)
344 		FREE(resp, M_NETGRAPH);
345 	FREE(msg, M_NETGRAPH);
346 	return (error);
347 }
348 
349 /*
350  * Receive data
351  */
352 static int
353 cisco_rcvdata(hook_p hook, struct mbuf *m, meta_p meta,
354 		struct mbuf **ret_m, meta_p *ret_meta)
355 {
356 	const sc_p sc = hook->node->private;
357 	struct protoent *pep;
358 	struct cisco_header *h;
359 	int error = 0;
360 
361 	if ((pep = hook->private) == NULL)
362 		goto out;
363 
364 	/* If it came from our downlink, deal with it separately */
365 	if (pep->af == 0xffff)
366 		return (cisco_input(sc, m, meta));
367 
368 	/* OK so it came from a protocol, heading out. Prepend general data
369 	   packet header. For now, IP,IPX only  */
370 	M_PREPEND(m, CISCO_HEADER_LEN, M_DONTWAIT);
371 	if (!m) {
372 		error = ENOBUFS;
373 		goto out;
374 	}
375 	h = mtod(m, struct cisco_header *);
376 	h->address = CISCO_UNICAST;
377 	h->control = 0;
378 
379 	switch (pep->af) {
380 	case AF_INET:		/* Internet Protocol */
381 		h->protocol = htons(ETHERTYPE_IP);
382 		break;
383 	case AF_INET6:
384 		h->protocol = htons(ETHERTYPE_IPV6);
385 		break;
386 	case AF_APPLETALK:	/* AppleTalk Protocol */
387 		h->protocol = htons(ETHERTYPE_AT);
388 		break;
389 	case AF_IPX:		/* Novell IPX Protocol */
390 		h->protocol = htons(ETHERTYPE_IPX);
391 		break;
392 	default:
393 		error = EAFNOSUPPORT;
394 		goto out;
395 	}
396 
397 	/* Send it */
398 	NG_SEND_DATA(error, sc->downstream.hook, m, meta);
399 	return (error);
400 
401 out:
402 	NG_FREE_DATA(m, meta);
403 	return (error);
404 }
405 
406 /*
407  * Shutdown node
408  */
409 static int
410 cisco_rmnode(node_p node)
411 {
412 	const sc_p sc = node->private;
413 
414 	node->flags |= NG_INVALID;
415 	ng_cutlinks(node);
416 	ng_unname(node);
417 	node->private = NULL;
418 	ng_unref(sc->node);
419 	FREE(sc, M_NETGRAPH);
420 	return (0);
421 }
422 
423 /*
424  * Disconnection of a hook
425  *
426  * For this type, removal of the last link destroys the node
427  */
428 static int
429 cisco_disconnect(hook_p hook)
430 {
431 	const sc_p sc = hook->node->private;
432 	struct protoent *pep;
433 
434 	/* Check it's not the debug hook */
435 	if ((pep = hook->private)) {
436 		pep->hook = NULL;
437 		if (pep->af == 0xffff) {
438 			/* If it is the downstream hook, stop the timers */
439 			untimeout(cisco_keepalive, sc, sc->handle);
440 		}
441 	}
442 
443 	/* If no more hooks, remove the node */
444 	if (hook->node->numhooks == 0)
445 		ng_rmnode(hook->node);
446 	return (0);
447 }
448 
449 /*
450  * Receive data
451  */
452 static int
453 cisco_input(sc_p sc, struct mbuf *m, meta_p meta)
454 {
455 	struct cisco_header *h;
456 	struct cisco_packet *p;
457 	struct protoent *pep;
458 	int error = 0;
459 
460 	if (m->m_pkthdr.len <= CISCO_HEADER_LEN)
461 		goto drop;
462 
463 	/* Strip off cisco header */
464 	h = mtod(m, struct cisco_header *);
465 	m_adj(m, CISCO_HEADER_LEN);
466 
467 	switch (h->address) {
468 	default:		/* Invalid Cisco packet. */
469 		goto drop;
470 	case CISCO_UNICAST:
471 	case CISCO_MULTICAST:
472 		/* Don't check the control field here (RFC 1547). */
473 		switch (ntohs(h->protocol)) {
474 		default:
475 			goto drop;
476 		case CISCO_KEEPALIVE:
477 			p = mtod(m, struct cisco_packet *);
478 			switch (ntohl(p->type)) {
479 			default:
480 				log(LOG_WARNING,
481 				    "cisco: unknown cisco packet type: 0x%lx\n",
482 				       ntohl(p->type));
483 				break;
484 			case CISCO_ADDR_REPLY:
485 				/* Reply on address request, ignore */
486 				break;
487 			case CISCO_KEEPALIVE_REQ:
488 				sc->remote_seq = ntohl(p->par1);
489 				if (sc->local_seq == ntohl(p->par2)) {
490 					sc->local_seq++;
491 					sc->seqRetries = 0;
492 				}
493 				break;
494 			case CISCO_ADDR_REQ:
495 			    {
496 				struct ng_mesg *msg, *resp;
497 
498 				/* Ask inet peer for IP address information */
499 				if (sc->inet.hook == NULL)
500 					goto nomsg;
501 				NG_MKMESSAGE(msg, NGM_CISCO_COOKIE,
502 				    NGM_CISCO_GET_IPADDR, 0, M_NOWAIT);
503 				if (msg == NULL)
504 					goto nomsg;
505 				ng_send_msg(sc->node, msg,
506 				    NG_CISCO_HOOK_INET, &resp);
507 				if (resp != NULL)
508 					cisco_rcvmsg(sc->node, resp, ".",
509 								NULL, NULL);
510 
511 		nomsg:
512 				/* Send reply to peer device */
513 				error = cisco_send(sc, CISCO_ADDR_REPLY,
514 					    ntohl(sc->localip.s_addr),
515 					    ntohl(sc->localmask.s_addr));
516 				break;
517 			    }
518 			}
519 			goto drop;
520 		case ETHERTYPE_IP:
521 			pep = &sc->inet;
522 			break;
523 		case ETHERTYPE_IPV6:
524 			pep = &sc->inet6;
525 			break;
526 		case ETHERTYPE_AT:
527 			pep = &sc->atalk;
528 			break;
529 		case ETHERTYPE_IPX:
530 			pep = &sc->ipx;
531 			break;
532 		}
533 		break;
534 	}
535 
536 	/* Send it on */
537 	if (pep->hook == NULL)
538 		goto drop;
539 	NG_SEND_DATA(error, pep->hook, m, meta);
540 	return (error);
541 
542 drop:
543 	NG_FREE_DATA(m, meta);
544 	return (error);
545 }
546 
547 
548 /*
549  * Send keepalive packets, every 10 seconds.
550  */
551 static void
552 cisco_keepalive(void *arg)
553 {
554 	const sc_p sc = arg;
555 	int s = splimp();
556 
557 	cisco_send(sc, CISCO_KEEPALIVE_REQ, sc->local_seq, sc->remote_seq);
558 	sc->seqRetries++;
559 	splx(s);
560 	sc->handle = timeout(cisco_keepalive, sc, hz * KEEPALIVE_SECS);
561 }
562 
563 /*
564  * Send Cisco keepalive packet.
565  */
566 static int
567 cisco_send(sc_p sc, int type, long par1, long par2)
568 {
569 	struct cisco_header *h;
570 	struct cisco_packet *ch;
571 	struct mbuf *m;
572 	u_long  t;
573 	int     error = 0;
574 	meta_p  meta = NULL;
575 	struct timeval time;
576 
577 	getmicrotime(&time);
578 
579 	MGETHDR(m, M_DONTWAIT, MT_DATA);
580 	if (!m)
581 		return (ENOBUFS);
582 
583 	t = (time.tv_sec - boottime.tv_sec) * 1000;
584 	m->m_pkthdr.len = m->m_len = CISCO_HEADER_LEN + CISCO_PACKET_LEN;
585 	m->m_pkthdr.rcvif = 0;
586 
587 	h = mtod(m, struct cisco_header *);
588 	h->address = CISCO_MULTICAST;
589 	h->control = 0;
590 	h->protocol = htons(CISCO_KEEPALIVE);
591 
592 	ch = (struct cisco_packet *) (h + 1);
593 	ch->type = htonl(type);
594 	ch->par1 = htonl(par1);
595 	ch->par2 = htonl(par2);
596 	ch->rel = -1;
597 	ch->time0 = htons((u_short) (t >> 16));
598 	ch->time1 = htons((u_short) t);
599 
600 	NG_SEND_DATA(error, sc->downstream.hook, m, meta);
601 	return (error);
602 }
603