xref: /dragonfly/sys/netgraph/cisco/ng_cisco.c (revision 7b0266d8)
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: src/sys/netgraph/ng_cisco.c,v 1.4.2.6 2002/07/02 23:44:02 archie Exp $
40  * $DragonFly: src/sys/netgraph/cisco/ng_cisco.c,v 1.6 2004/09/16 03:43:07 dillon Exp $
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 <netproto/atalk/at.h>
59 
60 #include <netproto/ipx/ipx.h>
61 #include <netproto/ipx/ipx_if.h>
62 
63 #include <netgraph/ng_message.h>
64 #include <netgraph/netgraph.h>
65 #include <netgraph/ng_parse.h>
66 #include "ng_cisco.h"
67 
68 #define CISCO_MULTICAST         0x8f	/* Cisco multicast address */
69 #define CISCO_UNICAST           0x0f	/* Cisco unicast address */
70 #define CISCO_KEEPALIVE         0x8035	/* Cisco keepalive protocol */
71 #define CISCO_ADDR_REQ          0	/* Cisco address request */
72 #define CISCO_ADDR_REPLY        1	/* Cisco address reply */
73 #define CISCO_KEEPALIVE_REQ     2	/* Cisco keepalive request */
74 
75 #define KEEPALIVE_SECS		10
76 
77 struct cisco_header {
78 	u_char  address;
79 	u_char  control;
80 	u_short protocol;
81 };
82 
83 #define CISCO_HEADER_LEN          sizeof (struct cisco_header)
84 
85 struct cisco_packet {
86 	u_long  type;
87 	u_long  par1;
88 	u_long  par2;
89 	u_short rel;
90 	u_short time0;
91 	u_short time1;
92 };
93 
94 #define CISCO_PACKET_LEN (sizeof(struct cisco_packet))
95 
96 struct protoent {
97 	hook_p  hook;		/* the hook for this proto */
98 	u_short af;		/* address family, -1 = downstream */
99 };
100 
101 struct cisco_priv {
102 	u_long  local_seq;
103 	u_long  remote_seq;
104 	u_long  seqRetries;	/* how many times we've been here throwing out
105 				 * the same sequence number without ack */
106 	node_p  node;
107 	struct callout timeout;
108 	struct protoent downstream;
109 	struct protoent inet;		/* IP information */
110 	struct in_addr localip;
111 	struct in_addr localmask;
112 	struct protoent inet6;		/* IPv6 information */
113 	struct protoent atalk;		/* AppleTalk information */
114 	struct protoent ipx;		/* IPX information */
115 };
116 typedef struct cisco_priv *sc_p;
117 
118 /* Netgraph methods */
119 static ng_constructor_t		cisco_constructor;
120 static ng_rcvmsg_t		cisco_rcvmsg;
121 static ng_shutdown_t		cisco_rmnode;
122 static ng_newhook_t		cisco_newhook;
123 static ng_rcvdata_t		cisco_rcvdata;
124 static ng_disconnect_t		cisco_disconnect;
125 
126 /* Other functions */
127 static int	cisco_input(sc_p sc, struct mbuf *m, meta_p meta);
128 static void	cisco_keepalive(void *arg);
129 static int	cisco_send(sc_p sc, int type, long par1, long par2);
130 
131 /* Parse type for struct ng_cisco_ipaddr */
132 static const struct ng_parse_struct_field ng_cisco_ipaddr_type_fields[]
133 	= NG_CISCO_IPADDR_TYPE_INFO;
134 static const struct ng_parse_type ng_cisco_ipaddr_type = {
135 	&ng_parse_struct_type,
136 	&ng_cisco_ipaddr_type_fields
137 };
138 
139 /* Parse type for struct ng_async_stat */
140 static const struct ng_parse_struct_field ng_cisco_stats_type_fields[]
141 	= NG_CISCO_STATS_TYPE_INFO;
142 static const struct ng_parse_type ng_cisco_stats_type = {
143 	&ng_parse_struct_type,
144 	&ng_cisco_stats_type_fields
145 };
146 
147 /* List of commands and how to convert arguments to/from ASCII */
148 static const struct ng_cmdlist ng_cisco_cmdlist[] = {
149 	{
150 	  NGM_CISCO_COOKIE,
151 	  NGM_CISCO_SET_IPADDR,
152 	  "setipaddr",
153 	  &ng_cisco_ipaddr_type,
154 	  NULL
155 	},
156 	{
157 	  NGM_CISCO_COOKIE,
158 	  NGM_CISCO_GET_IPADDR,
159 	  "getipaddr",
160 	  NULL,
161 	  &ng_cisco_ipaddr_type
162 	},
163 	{
164 	  NGM_CISCO_COOKIE,
165 	  NGM_CISCO_GET_STATUS,
166 	  "getstats",
167 	  NULL,
168 	  &ng_cisco_stats_type
169 	},
170 	{ 0 }
171 };
172 
173 /* Node type */
174 static struct ng_type typestruct = {
175 	NG_VERSION,
176 	NG_CISCO_NODE_TYPE,
177 	NULL,
178 	cisco_constructor,
179 	cisco_rcvmsg,
180 	cisco_rmnode,
181 	cisco_newhook,
182 	NULL,
183 	NULL,
184 	cisco_rcvdata,
185 	cisco_rcvdata,
186 	cisco_disconnect,
187 	ng_cisco_cmdlist
188 };
189 NETGRAPH_INIT(cisco, &typestruct);
190 
191 /*
192  * Node constructor
193  */
194 static int
195 cisco_constructor(node_p *nodep)
196 {
197 	sc_p sc;
198 	int error = 0;
199 
200 	MALLOC(sc, sc_p, sizeof(*sc), M_NETGRAPH, M_NOWAIT);
201 	if (sc == NULL)
202 		return (ENOMEM);
203 	bzero(sc, sizeof(struct cisco_priv));
204 
205 	callout_init(&sc->timeout);
206 	if ((error = ng_make_node_common(&typestruct, nodep))) {
207 		FREE(sc, M_NETGRAPH);
208 		return (error);
209 	}
210 	(*nodep)->private = sc;
211 	sc->node = *nodep;
212 
213 	/* Initialise the varous protocol hook holders */
214 	sc->downstream.af = 0xffff;
215 	sc->inet.af = AF_INET;
216 	sc->inet6.af = AF_INET6;
217 	sc->atalk.af = AF_APPLETALK;
218 	sc->ipx.af = AF_IPX;
219 	return (0);
220 }
221 
222 /*
223  * Check new hook
224  */
225 static int
226 cisco_newhook(node_p node, hook_p hook, const char *name)
227 {
228 	const sc_p sc = node->private;
229 
230 	if (strcmp(name, NG_CISCO_HOOK_DOWNSTREAM) == 0) {
231 		sc->downstream.hook = hook;
232 		hook->private = &sc->downstream;
233 
234 		/* Start keepalives */
235 		callout_reset(&sc->timeout, hz * KEEPALIVE_SECS,
236 				cisco_keepalive, sc);
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, MB_DONTWAIT);
373 	if (!m) {
374 		error = ENOBUFS;
375 		goto out;
376 	}
377 	h = mtod(m, struct cisco_header *);
378 	h->address = CISCO_UNICAST;
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_INET6:
386 		h->protocol = htons(ETHERTYPE_IPV6);
387 		break;
388 	case AF_APPLETALK:	/* AppleTalk Protocol */
389 		h->protocol = htons(ETHERTYPE_AT);
390 		break;
391 	case AF_IPX:		/* Novell IPX Protocol */
392 		h->protocol = htons(ETHERTYPE_IPX);
393 		break;
394 	default:
395 		error = EAFNOSUPPORT;
396 		goto out;
397 	}
398 
399 	/* Send it */
400 	NG_SEND_DATA(error, sc->downstream.hook, m, meta);
401 	return (error);
402 
403 out:
404 	NG_FREE_DATA(m, meta);
405 	return (error);
406 }
407 
408 /*
409  * Shutdown node
410  */
411 static int
412 cisco_rmnode(node_p node)
413 {
414 	const sc_p sc = node->private;
415 
416 	node->flags |= NG_INVALID;
417 	ng_cutlinks(node);
418 	ng_unname(node);
419 	node->private = NULL;
420 	ng_unref(sc->node);
421 	FREE(sc, M_NETGRAPH);
422 	return (0);
423 }
424 
425 /*
426  * Disconnection of a hook
427  *
428  * For this type, removal of the last link destroys the node
429  */
430 static int
431 cisco_disconnect(hook_p hook)
432 {
433 	const sc_p sc = hook->node->private;
434 	struct protoent *pep;
435 
436 	/* Check it's not the debug hook */
437 	if ((pep = hook->private)) {
438 		pep->hook = NULL;
439 		if (pep->af == 0xffff) {
440 			/* If it is the downstream hook, stop the timers */
441 			callout_stop(&sc->timeout);
442 		}
443 	}
444 
445 	/* If no more hooks, remove the node */
446 	if (hook->node->numhooks == 0)
447 		ng_rmnode(hook->node);
448 	return (0);
449 }
450 
451 /*
452  * Receive data
453  */
454 static int
455 cisco_input(sc_p sc, struct mbuf *m, meta_p meta)
456 {
457 	const struct cisco_header *h;
458 	struct cisco_header hdrbuf;
459 	struct protoent *pep;
460 	int error = 0;
461 
462 	/* Sanity check header length */
463 	if (m->m_pkthdr.len < sizeof(*h)) {
464 		error = EINVAL;
465 		goto drop;
466 	}
467 
468 	/* Get cisco header */
469 	if (m->m_len >= sizeof(*h))			/* the common case */
470 		h = mtod(m, const struct cisco_header *);
471 	else {
472 		m_copydata(m, 0, sizeof(*h), (caddr_t)&hdrbuf);
473 		h = &hdrbuf;
474 	}
475 	m_adj(m, sizeof(*h));
476 
477 	/* Check header address */
478 	switch (h->address) {
479 	default:		/* Invalid Cisco packet. */
480 		goto drop;
481 	case CISCO_UNICAST:
482 	case CISCO_MULTICAST:
483 		/* Don't check the control field here (RFC 1547). */
484 		switch (ntohs(h->protocol)) {
485 		default:
486 			goto drop;
487 		case CISCO_KEEPALIVE:
488 		    {
489 			const struct cisco_packet *p;
490 			struct cisco_packet pktbuf;
491 
492 			/* Sanity check packet length */
493 			if (m->m_pkthdr.len < sizeof(*p)) {
494 				error = EINVAL;
495 				goto drop;
496 			}
497 
498 			/* Get cisco packet */
499 			if (m->m_len >= sizeof(*p))	/* the common case */
500 				p = mtod(m, const struct cisco_packet *);
501 			else {
502 				m_copydata(m, 0, sizeof(*p), (caddr_t)&pktbuf);
503 				p = &pktbuf;
504 			}
505 
506 			/* Check packet type */
507 			switch (ntohl(p->type)) {
508 			default:
509 				log(LOG_WARNING,
510 				    "cisco: unknown cisco packet type: 0x%lx\n",
511 				       ntohl(p->type));
512 				break;
513 			case CISCO_ADDR_REPLY:
514 				/* Reply on address request, ignore */
515 				break;
516 			case CISCO_KEEPALIVE_REQ:
517 				sc->remote_seq = ntohl(p->par1);
518 				if (sc->local_seq == ntohl(p->par2)) {
519 					sc->local_seq++;
520 					sc->seqRetries = 0;
521 				}
522 				break;
523 			case CISCO_ADDR_REQ:
524 			    {
525 				struct ng_mesg *msg, *resp;
526 
527 				/* Ask inet peer for IP address information */
528 				if (sc->inet.hook == NULL)
529 					goto nomsg;
530 				NG_MKMESSAGE(msg, NGM_CISCO_COOKIE,
531 				    NGM_CISCO_GET_IPADDR, 0, M_NOWAIT);
532 				if (msg == NULL)
533 					goto nomsg;
534 				ng_send_msg(sc->node, msg,
535 				    NG_CISCO_HOOK_INET, &resp);
536 				if (resp != NULL)
537 					cisco_rcvmsg(sc->node, resp, ".", NULL);
538 
539 		nomsg:
540 				/* Send reply to peer device */
541 				error = cisco_send(sc, CISCO_ADDR_REPLY,
542 					    ntohl(sc->localip.s_addr),
543 					    ntohl(sc->localmask.s_addr));
544 				break;
545 			    }
546 			}
547 			goto drop;
548 		    }
549 		case ETHERTYPE_IP:
550 			pep = &sc->inet;
551 			break;
552 		case ETHERTYPE_IPV6:
553 			pep = &sc->inet6;
554 			break;
555 		case ETHERTYPE_AT:
556 			pep = &sc->atalk;
557 			break;
558 		case ETHERTYPE_IPX:
559 			pep = &sc->ipx;
560 			break;
561 		}
562 		break;
563 	}
564 
565 	/* Drop if payload is empty */
566 	if (m->m_pkthdr.len == 0) {
567 		error = EINVAL;
568 		goto drop;
569 	}
570 
571 	/* Send it on */
572 	if (pep->hook == NULL)
573 		goto drop;
574 	NG_SEND_DATA(error, pep->hook, m, meta);
575 	return (error);
576 
577 drop:
578 	NG_FREE_DATA(m, meta);
579 	return (error);
580 }
581 
582 
583 /*
584  * Send keepalive packets, every 10 seconds.
585  */
586 static void
587 cisco_keepalive(void *arg)
588 {
589 	const sc_p sc = arg;
590 	int s = splimp();
591 
592 	cisco_send(sc, CISCO_KEEPALIVE_REQ, sc->local_seq, sc->remote_seq);
593 	sc->seqRetries++;
594 	splx(s);
595 	callout_reset(&sc->timeout, hz * KEEPALIVE_SECS,
596 			cisco_keepalive, sc);
597 }
598 
599 /*
600  * Send Cisco keepalive packet.
601  */
602 static int
603 cisco_send(sc_p sc, int type, long par1, long par2)
604 {
605 	struct cisco_header *h;
606 	struct cisco_packet *ch;
607 	struct mbuf *m;
608 	u_long  t;
609 	int     error = 0;
610 	meta_p  meta = NULL;
611 	struct timeval time;
612 
613 	getmicrotime(&time);
614 
615 	MGETHDR(m, MB_DONTWAIT, MT_DATA);
616 	if (!m)
617 		return (ENOBUFS);
618 
619 	t = (time.tv_sec - boottime.tv_sec) * 1000;
620 	m->m_pkthdr.len = m->m_len = CISCO_HEADER_LEN + CISCO_PACKET_LEN;
621 	m->m_pkthdr.rcvif = 0;
622 
623 	h = mtod(m, struct cisco_header *);
624 	h->address = CISCO_MULTICAST;
625 	h->control = 0;
626 	h->protocol = htons(CISCO_KEEPALIVE);
627 
628 	ch = (struct cisco_packet *) (h + 1);
629 	ch->type = htonl(type);
630 	ch->par1 = htonl(par1);
631 	ch->par2 = htonl(par2);
632 	ch->rel = -1;
633 	ch->time0 = htons((u_short) (t >> 16));
634 	ch->time1 = htons((u_short) t);
635 
636 	NG_SEND_DATA(error, sc->downstream.hook, m, meta);
637 	return (error);
638 }
639