xref: /freebsd/sys/netgraph/ng_cisco.c (revision 5129159789cc9d7bc514e4546b88e3427695002d)
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@whistle.com>
38  *
39  * $FreeBSD$
40  * $Whistle: ng_cisco.c,v 1.25 1999/11/01 09:24:51 julian Exp $
41  */
42 
43 #include "opt_inet.h"
44 #include "opt_atalk.h"
45 #include "opt_ipx.h"
46 
47 #include <sys/param.h>
48 #include <sys/systm.h>
49 #include <sys/errno.h>
50 #include <sys/kernel.h>
51 #include <sys/socket.h>
52 #include <sys/malloc.h>
53 #include <sys/mbuf.h>
54 #include <sys/syslog.h>
55 
56 #include <net/if.h>
57 
58 #include <netinet/in.h>
59 #include <netinet/if_ether.h>
60 
61 #include <netatalk/at.h>
62 
63 #include <netipx/ipx.h>
64 #include <netipx/ipx_if.h>
65 
66 #include <netgraph/ng_message.h>
67 #include <netgraph/netgraph.h>
68 #include <netgraph/ng_parse.h>
69 #include <netgraph/ng_cisco.h>
70 
71 #define CISCO_MULTICAST         0x8f	/* Cisco multicast address */
72 #define CISCO_UNICAST           0x0f	/* Cisco unicast address */
73 #define CISCO_KEEPALIVE         0x8035	/* Cisco keepalive protocol */
74 #define CISCO_ADDR_REQ          0	/* Cisco address request */
75 #define CISCO_ADDR_REPLY        1	/* Cisco address reply */
76 #define CISCO_KEEPALIVE_REQ     2	/* Cisco keepalive request */
77 
78 #define KEEPALIVE_SECS		10
79 
80 struct cisco_header {
81 	u_char  address;
82 	u_char  control;
83 	u_short protocol;
84 };
85 
86 #define CISCO_HEADER_LEN          sizeof (struct cisco_header)
87 
88 struct cisco_packet {
89 	u_long  type;
90 	u_long  par1;
91 	u_long  par2;
92 	u_short rel;
93 	u_short time0;
94 	u_short time1;
95 };
96 
97 #define CISCO_PACKET_LEN (sizeof(struct cisco_packet))
98 
99 struct protoent {
100 	hook_p  hook;		/* the hook for this proto */
101 	u_short af;		/* address family, -1 = downstream */
102 };
103 
104 struct cisco_priv {
105 	u_long  local_seq;
106 	u_long  remote_seq;
107 	u_long  seqRetries;	/* how many times we've been here throwing out
108 				 * the same sequence number without ack */
109 	node_p  node;
110 	struct callout_handle handle;
111 	struct protoent downstream;
112 	struct protoent inet;		/* IP information */
113 	struct in_addr localip;
114 	struct in_addr localmask;
115 	struct protoent atalk;		/* AppleTalk information */
116 	struct protoent ipx;		/* IPX information */
117 };
118 typedef struct cisco_priv *sc_p;
119 
120 /* Netgraph methods */
121 static ng_constructor_t		cisco_constructor;
122 static ng_rcvmsg_t		cisco_rcvmsg;
123 static ng_shutdown_t		cisco_rmnode;
124 static ng_newhook_t		cisco_newhook;
125 static ng_rcvdata_t		cisco_rcvdata;
126 static ng_disconnect_t		cisco_disconnect;
127 
128 /* Other functions */
129 static int	cisco_input(sc_p sc, struct mbuf *m, meta_p meta);
130 static void	cisco_keepalive(void *arg);
131 static int	cisco_send(sc_p sc, int type, long par1, long par2);
132 
133 /* Parse type for struct ng_cisco_ipaddr */
134 static const struct ng_parse_struct_info
135 	ng_cisco_ipaddr_type_info = NG_CISCO_IPADDR_TYPE_INFO;
136 static const struct ng_parse_type ng_cisco_ipaddr_type = {
137 	&ng_parse_struct_type,
138 	&ng_cisco_ipaddr_type_info
139 };
140 
141 /* Parse type for struct ng_async_stat */
142 static const struct ng_parse_struct_info
143 	ng_cisco_stats_type_info = NG_CISCO_STATS_TYPE_INFO;
144 static const struct ng_parse_type ng_cisco_stats_type = {
145 	&ng_parse_struct_type,
146 	&ng_cisco_stats_type_info,
147 };
148 
149 /* List of commands and how to convert arguments to/from ASCII */
150 static const struct ng_cmdlist ng_cisco_cmdlist[] = {
151 	{
152 	  NGM_CISCO_COOKIE,
153 	  NGM_CISCO_SET_IPADDR,
154 	  "setipaddr",
155 	  &ng_cisco_ipaddr_type,
156 	  NULL
157 	},
158 	{
159 	  NGM_CISCO_COOKIE,
160 	  NGM_CISCO_GET_IPADDR,
161 	  "getipaddr",
162 	  NULL,
163 	  &ng_cisco_ipaddr_type
164 	},
165 	{
166 	  NGM_CISCO_COOKIE,
167 	  NGM_CISCO_GET_STATUS,
168 	  "getstats",
169 	  NULL,
170 	  &ng_cisco_stats_type
171 	},
172 	{ 0 }
173 };
174 
175 /* Node type */
176 static struct ng_type typestruct = {
177 	NG_VERSION,
178 	NG_CISCO_NODE_TYPE,
179 	NULL,
180 	cisco_constructor,
181 	cisco_rcvmsg,
182 	cisco_rmnode,
183 	cisco_newhook,
184 	NULL,
185 	NULL,
186 	cisco_rcvdata,
187 	cisco_rcvdata,
188 	cisco_disconnect,
189 	ng_cisco_cmdlist
190 };
191 NETGRAPH_INIT(cisco, &typestruct);
192 
193 /*
194  * Node constructor
195  */
196 static int
197 cisco_constructor(node_p *nodep)
198 {
199 	sc_p sc;
200 	int error = 0;
201 
202 	MALLOC(sc, sc_p, sizeof(*sc), M_NETGRAPH, M_WAITOK);
203 	if (sc == NULL)
204 		return (ENOMEM);
205 	bzero(sc, sizeof(struct cisco_priv));
206 
207 	callout_handle_init(&sc->handle);
208 	if ((error = ng_make_node_common(&typestruct, nodep))) {
209 		FREE(sc, M_NETGRAPH);
210 		return (error);
211 	}
212 	(*nodep)->private = sc;
213 	sc->node = *nodep;
214 
215 	/* Initialise the varous protocol hook holders */
216 	sc->downstream.af = 0xffff;
217 	sc->inet.af = AF_INET;
218 	sc->atalk.af = AF_APPLETALK;
219 	sc->ipx.af = AF_IPX;
220 	return (0);
221 }
222 
223 /*
224  * Check new hook
225  */
226 static int
227 cisco_newhook(node_p node, hook_p hook, const char *name)
228 {
229 	const sc_p sc = node->private;
230 
231 	if (strcmp(name, NG_CISCO_HOOK_DOWNSTREAM) == 0) {
232 		sc->downstream.hook = hook;
233 		hook->private = &sc->downstream;
234 
235 		/* Start keepalives */
236 		sc->handle = timeout(cisco_keepalive, sc, hz * KEEPALIVE_SECS);
237 	} else if (strcmp(name, NG_CISCO_HOOK_INET) == 0) {
238 		sc->inet.hook = hook;
239 		hook->private = &sc->inet;
240 	} else if (strcmp(name, NG_CISCO_HOOK_APPLETALK) == 0) {
241 		sc->atalk.hook = hook;
242 		hook->private = &sc->atalk;
243 	} else if (strcmp(name, NG_CISCO_HOOK_IPX) == 0) {
244 		sc->ipx.hook = hook;
245 		hook->private = &sc->ipx;
246 	} else if (strcmp(name, NG_CISCO_HOOK_DEBUG) == 0) {
247 		hook->private = NULL;	/* unimplemented */
248 	} else
249 		return (EINVAL);
250 	return 0;
251 }
252 
253 /*
254  * Receive control message.
255  */
256 static int
257 cisco_rcvmsg(node_p node, struct ng_mesg *msg,
258 	const char *retaddr, struct ng_mesg **rptr)
259 {
260 	const sc_p sc = node->private;
261 	struct ng_mesg *resp = NULL;
262 	int error = 0;
263 
264 	switch (msg->header.typecookie) {
265 	case NGM_GENERIC_COOKIE:
266 		switch (msg->header.cmd) {
267 		case NGM_TEXT_STATUS:
268 		    {
269 			char *arg;
270 			int pos;
271 
272 			NG_MKRESPONSE(resp, msg, sizeof(struct ng_mesg)
273 			    + NG_TEXTRESPONSE, M_NOWAIT);
274 			if (resp == NULL) {
275 				error = ENOMEM;
276 				break;
277 			}
278 			arg = (char *) resp->data;
279 			pos = sprintf(arg,
280 			  "keepalive period: %d sec; ", KEEPALIVE_SECS);
281 			pos += sprintf(arg + pos,
282 			  "unacknowledged keepalives: %ld", sc->seqRetries);
283 			resp->header.arglen = pos + 1;
284 			break;
285 		    }
286 		default:
287 			error = EINVAL;
288 			break;
289 		}
290 		break;
291 	case NGM_CISCO_COOKIE:
292 		switch (msg->header.cmd) {
293 		case NGM_CISCO_GET_IPADDR:	/* could be a late reply! */
294 			if ((msg->header.flags & NGF_RESP) == 0) {
295 				struct in_addr *ips;
296 
297 				NG_MKRESPONSE(resp, msg,
298 				    2 * sizeof(*ips), M_NOWAIT);
299 				if (!resp) {
300 					error = ENOMEM;
301 					break;
302 				}
303 				ips = (struct in_addr *) resp->data;
304 				ips[0] = sc->localip;
305 				ips[1] = sc->localmask;
306 				break;
307 			}
308 			/* FALLTHROUGH */	/* ...if it's a reply */
309 		case NGM_CISCO_SET_IPADDR:
310 		    {
311 			struct in_addr *const ips = (struct in_addr *)msg->data;
312 
313 			if (msg->header.arglen < 2 * sizeof(*ips)) {
314 				error = EINVAL;
315 				break;
316 			}
317 			sc->localip = ips[0];
318 			sc->localmask = ips[1];
319 			break;
320 		    }
321 		case NGM_CISCO_GET_STATUS:
322 		    {
323 			struct ng_cisco_stats *stat;
324 
325 			NG_MKRESPONSE(resp, msg, sizeof(*stat), M_NOWAIT);
326 			if (!resp) {
327 				error = ENOMEM;
328 				break;
329 			}
330 			stat = (struct ng_cisco_stats *)resp->data;
331 			stat->seqRetries = sc->seqRetries;
332 			stat->keepAlivePeriod = KEEPALIVE_SECS;
333 			break;
334 		    }
335 		default:
336 			error = EINVAL;
337 			break;
338 		}
339 		break;
340 	default:
341 		error = EINVAL;
342 		break;
343 	}
344 	if (rptr)
345 		*rptr = resp;
346 	else if (resp)
347 		FREE(resp, M_NETGRAPH);
348 	FREE(msg, M_NETGRAPH);
349 	return (error);
350 }
351 
352 /*
353  * Receive data
354  */
355 static int
356 cisco_rcvdata(hook_p hook, struct mbuf *m, meta_p meta)
357 {
358 	const sc_p sc = hook->node->private;
359 	struct protoent *pep;
360 	struct cisco_header *h;
361 	int error = 0;
362 
363 	if ((pep = hook->private) == NULL)
364 		goto out;
365 
366 	/* If it came from our downlink, deal with it separately */
367 	if (pep->af == 0xffff)
368 		return (cisco_input(sc, m, meta));
369 
370 	/* OK so it came from a protocol, heading out. Prepend general data
371 	   packet header. For now, IP,IPX only  */
372 	M_PREPEND(m, CISCO_HEADER_LEN, M_DONTWAIT);
373 	if (!m) {
374 		error = ENOBUFS;
375 		goto out;
376 	}
377 	h = mtod(m, struct cisco_header *);
378 	h->address = CISCO_MULTICAST;		/* broadcast address */
379 	h->control = 0;
380 
381 	switch (pep->af) {
382 	case AF_INET:		/* Internet Protocol */
383 		h->protocol = htons(ETHERTYPE_IP);
384 		break;
385 	case AF_APPLETALK:	/* AppleTalk Protocol */
386 		h->protocol = htons(ETHERTYPE_AT);
387 		break;
388 	case AF_IPX:		/* Novell IPX Protocol */
389 		h->protocol = htons(ETHERTYPE_IPX);
390 		break;
391 	default:
392 		error = EAFNOSUPPORT;
393 		goto out;
394 	}
395 
396 	/* Send it */
397 	NG_SEND_DATA(error, sc->downstream.hook, m, meta);
398 	return (error);
399 
400 out:
401 	NG_FREE_DATA(m, meta);
402 	return (error);
403 }
404 
405 /*
406  * Shutdown node
407  */
408 static int
409 cisco_rmnode(node_p node)
410 {
411 	const sc_p sc = node->private;
412 
413 	node->flags |= NG_INVALID;
414 	ng_cutlinks(node);
415 	ng_unname(node);
416 	node->private = NULL;
417 	ng_unref(sc->node);
418 	FREE(sc, M_NETGRAPH);
419 	return (0);
420 }
421 
422 /*
423  * Disconnection of a hook
424  *
425  * For this type, removal of the last link destroys the node
426  */
427 static int
428 cisco_disconnect(hook_p hook)
429 {
430 	const sc_p sc = hook->node->private;
431 	struct protoent *pep;
432 
433 	/* Check it's not the debug hook */
434 	if ((pep = hook->private)) {
435 		pep->hook = NULL;
436 		if (pep->af == 0xffff) {
437 			/* If it is the downstream hook, stop the timers */
438 			untimeout(cisco_keepalive, sc, sc->handle);
439 		}
440 	}
441 
442 	/* If no more hooks, remove the node */
443 	if (hook->node->numhooks == 0)
444 		ng_rmnode(hook->node);
445 	return (0);
446 }
447 
448 /*
449  * Receive data
450  */
451 static int
452 cisco_input(sc_p sc, struct mbuf *m, meta_p meta)
453 {
454 	struct cisco_header *h;
455 	struct cisco_packet *p;
456 	struct protoent *pep;
457 	int error = 0;
458 
459 	if (m->m_pkthdr.len <= CISCO_HEADER_LEN)
460 		goto drop;
461 
462 	/* Strip off cisco header */
463 	h = mtod(m, struct cisco_header *);
464 	m_adj(m, CISCO_HEADER_LEN);
465 
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 			p = mtod(m, struct cisco_packet *);
477 			switch (ntohl(p->type)) {
478 			default:
479 				log(LOG_WARNING,
480 				    "cisco: unknown cisco packet type: 0x%lx\n",
481 				       ntohl(p->type));
482 				break;
483 			case CISCO_ADDR_REPLY:
484 				/* Reply on address request, ignore */
485 				break;
486 			case CISCO_KEEPALIVE_REQ:
487 				sc->remote_seq = ntohl(p->par1);
488 				if (sc->local_seq == ntohl(p->par2)) {
489 					sc->local_seq++;
490 					sc->seqRetries = 0;
491 				}
492 				break;
493 			case CISCO_ADDR_REQ:
494 			    {
495 				struct ng_mesg *msg, *resp;
496 
497 				/* Ask inet peer for IP address information */
498 				if (sc->inet.hook == NULL)
499 					goto nomsg;
500 				NG_MKMESSAGE(msg, NGM_CISCO_COOKIE,
501 				    NGM_CISCO_GET_IPADDR, 0, M_NOWAIT);
502 				if (msg == NULL)
503 					goto nomsg;
504 				ng_send_msg(sc->node, msg,
505 				    NG_CISCO_HOOK_INET, &resp);
506 				if (resp != NULL)
507 					cisco_rcvmsg(sc->node, resp, ".", NULL);
508 
509 		nomsg:
510 				/* Send reply to peer device */
511 				error = cisco_send(sc, CISCO_ADDR_REPLY,
512 					    ntohl(sc->localip.s_addr),
513 					    ntohl(sc->localmask.s_addr));
514 				break;
515 			    }
516 			}
517 			goto drop;
518 		case ETHERTYPE_IP:
519 			pep = &sc->inet;
520 			break;
521 		case ETHERTYPE_AT:
522 			pep = &sc->atalk;
523 			break;
524 		case ETHERTYPE_IPX:
525 			pep = &sc->ipx;
526 			break;
527 		}
528 		break;
529 	}
530 
531 	/* Send it on */
532 	if (pep->hook == NULL)
533 		goto drop;
534 	NG_SEND_DATA(error, pep->hook, m, meta);
535 	return (error);
536 
537 drop:
538 	NG_FREE_DATA(m, meta);
539 	return (error);
540 }
541 
542 
543 /*
544  * Send keepalive packets, every 10 seconds.
545  */
546 static void
547 cisco_keepalive(void *arg)
548 {
549 	const sc_p sc = arg;
550 	int s = splimp();
551 
552 	cisco_send(sc, CISCO_KEEPALIVE_REQ, sc->local_seq, sc->remote_seq);
553 	sc->seqRetries++;
554 	splx(s);
555 	sc->handle = timeout(cisco_keepalive, sc, hz * KEEPALIVE_SECS);
556 }
557 
558 /*
559  * Send Cisco keepalive packet.
560  */
561 static int
562 cisco_send(sc_p sc, int type, long par1, long par2)
563 {
564 	struct cisco_header *h;
565 	struct cisco_packet *ch;
566 	struct mbuf *m;
567 	u_long  t;
568 	int     error = 0;
569 	meta_p  meta = NULL;
570 	struct timeval time;
571 
572 	getmicrotime(&time);
573 
574 	MGETHDR(m, M_DONTWAIT, MT_DATA);
575 	if (!m)
576 		return (ENOBUFS);
577 
578 	t = (time.tv_sec - boottime.tv_sec) * 1000;
579 	m->m_pkthdr.len = m->m_len = CISCO_HEADER_LEN + CISCO_PACKET_LEN;
580 	m->m_pkthdr.rcvif = 0;
581 
582 	h = mtod(m, struct cisco_header *);
583 	h->address = CISCO_MULTICAST;
584 	h->control = 0;
585 	h->protocol = htons(CISCO_KEEPALIVE);
586 
587 	ch = (struct cisco_packet *) (h + 1);
588 	ch->type = htonl(type);
589 	ch->par1 = htonl(par1);
590 	ch->par2 = htonl(par2);
591 	ch->rel = -1;
592 	ch->time0 = htons((u_short) (t >> 16));
593 	ch->time1 = htons((u_short) t);
594 
595 	NG_SEND_DATA(error, sc->downstream.hook, m, meta);
596 	return (error);
597 }
598