xref: /dragonfly/sys/netgraph7/cisco/ng_cisco.c (revision 82730a9c)
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: src/sys/netgraph/ng_cisco.c,v 1.29 2007/11/30 23:27:39 julian 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/ipx/ipx.h>
59 #include <netproto/ipx/ipx_if.h>
60 
61 #include <netgraph7/ng_message.h>
62 #include <netgraph7/netgraph.h>
63 #include <netgraph7/ng_parse.h>
64 #include "ng_cisco.h"
65 
66 #define	CISCO_MULTICAST		0x8f	/* Cisco multicast address */
67 #define	CISCO_UNICAST		0x0f	/* Cisco unicast address */
68 #define	CISCO_KEEPALIVE		0x8035	/* Cisco keepalive protocol */
69 #define	CISCO_ADDR_REQ		0	/* Cisco address request */
70 #define	CISCO_ADDR_REPLY	1	/* Cisco address reply */
71 #define	CISCO_KEEPALIVE_REQ	2	/* Cisco keepalive request */
72 
73 #define KEEPALIVE_SECS		10
74 
75 struct cisco_header {
76 	u_char  address;
77 	u_char  control;
78 	u_short protocol;
79 };
80 
81 #define	CISCO_HEADER_LEN	sizeof (struct cisco_header)
82 
83 struct cisco_packet {
84 	u_long  type;
85 	u_long  par1;
86 	u_long  par2;
87 	u_short rel;
88 	u_short time0;
89 	u_short time1;
90 };
91 
92 #define	CISCO_PACKET_LEN (sizeof(struct cisco_packet))
93 
94 struct protoent {
95 	hook_p  hook;		/* the hook for this proto */
96 	u_short af;		/* address family, -1 = downstream */
97 };
98 
99 struct cisco_priv {
100 	u_long  local_seq;
101 	u_long  remote_seq;
102 	u_long  seqRetries;	/* how many times we've been here throwing out
103 				 * the same sequence number without ack */
104 	node_p  node;
105 	struct callout handle;
106 	struct protoent downstream;
107 	struct protoent inet;		/* IP information */
108 	struct in_addr localip;
109 	struct in_addr localmask;
110 	struct protoent inet6;		/* IPv6 information */
111 	struct protoent ipx;		/* IPX information */
112 };
113 typedef struct cisco_priv *sc_p;
114 
115 /* Netgraph methods */
116 static ng_constructor_t		cisco_constructor;
117 static ng_rcvmsg_t		cisco_rcvmsg;
118 static ng_shutdown_t		cisco_shutdown;
119 static ng_newhook_t		cisco_newhook;
120 static ng_rcvdata_t		cisco_rcvdata;
121 static ng_disconnect_t		cisco_disconnect;
122 
123 /* Other functions */
124 static int	cisco_input(sc_p sc, item_p item);
125 static void	cisco_keepalive(node_p node, hook_p hook, void *arg1, int arg2);
126 static int	cisco_send(sc_p sc, int type, long par1, long par2);
127 static void	cisco_notify(sc_p sc, uint32_t cmd);
128 
129 /* Parse type for struct ng_cisco_ipaddr */
130 static const struct ng_parse_struct_field ng_cisco_ipaddr_type_fields[]
131 	= NG_CISCO_IPADDR_TYPE_INFO;
132 static const struct ng_parse_type ng_cisco_ipaddr_type = {
133 	&ng_parse_struct_type,
134 	&ng_cisco_ipaddr_type_fields
135 };
136 
137 /* Parse type for struct ng_async_stat */
138 static const struct ng_parse_struct_field ng_cisco_stats_type_fields[]
139 	= NG_CISCO_STATS_TYPE_INFO;
140 static const struct ng_parse_type ng_cisco_stats_type = {
141 	&ng_parse_struct_type,
142 	&ng_cisco_stats_type_fields
143 };
144 
145 /* List of commands and how to convert arguments to/from ASCII */
146 static const struct ng_cmdlist ng_cisco_cmdlist[] = {
147 	{
148 	  NGM_CISCO_COOKIE,
149 	  NGM_CISCO_SET_IPADDR,
150 	  "setipaddr",
151 	  &ng_cisco_ipaddr_type,
152 	  NULL
153 	},
154 	{
155 	  NGM_CISCO_COOKIE,
156 	  NGM_CISCO_GET_IPADDR,
157 	  "getipaddr",
158 	  NULL,
159 	  &ng_cisco_ipaddr_type
160 	},
161 	{
162 	  NGM_CISCO_COOKIE,
163 	  NGM_CISCO_GET_STATUS,
164 	  "getstats",
165 	  NULL,
166 	  &ng_cisco_stats_type
167 	},
168 	{ 0 }
169 };
170 
171 /* Node type */
172 static struct ng_type typestruct = {
173 	.version =	NG_ABI_VERSION,
174 	.name =		NG_CISCO_NODE_TYPE,
175 	.constructor =	cisco_constructor,
176 	.rcvmsg =	cisco_rcvmsg,
177 	.shutdown =	cisco_shutdown,
178 	.newhook =	cisco_newhook,
179 	.rcvdata =	cisco_rcvdata,
180 	.disconnect =	cisco_disconnect,
181 	.cmdlist =	ng_cisco_cmdlist,
182 };
183 NETGRAPH_INIT(cisco, &typestruct);
184 
185 /*
186  * Node constructor
187  */
188 static int
189 cisco_constructor(node_p node)
190 {
191 	sc_p sc;
192 
193 	sc = kmalloc(sizeof(*sc), M_NETGRAPH, M_WAITOK | M_NULLOK | M_ZERO);
194 	if (sc == NULL)
195 		return (ENOMEM);
196 
197 	ng_callout_init(&sc->handle);
198 	NG_NODE_SET_PRIVATE(node, sc);
199 	sc->node = node;
200 
201 	/* Initialise the varous protocol hook holders */
202 	sc->downstream.af = 0xffff;
203 	sc->inet.af = AF_INET;
204 	sc->inet6.af = AF_INET6;
205 	sc->ipx.af = AF_IPX;
206 	return (0);
207 }
208 
209 /*
210  * Check new hook
211  */
212 static int
213 cisco_newhook(node_p node, hook_p hook, const char *name)
214 {
215 	const sc_p sc = NG_NODE_PRIVATE(node);
216 
217 	if (strcmp(name, NG_CISCO_HOOK_DOWNSTREAM) == 0) {
218 		sc->downstream.hook = hook;
219 		NG_HOOK_SET_PRIVATE(hook, &sc->downstream);
220 
221 		/* Start keepalives */
222 		ng_callout(&sc->handle, node, NULL, (hz * KEEPALIVE_SECS),
223 		    &cisco_keepalive, (void *)sc, 0);
224 	} else if (strcmp(name, NG_CISCO_HOOK_INET) == 0) {
225 		sc->inet.hook = hook;
226 		NG_HOOK_SET_PRIVATE(hook, &sc->inet);
227 	} else if (strcmp(name, NG_CISCO_HOOK_INET6) == 0) {
228 		sc->inet6.hook = hook;
229 		NG_HOOK_SET_PRIVATE(hook, &sc->inet6);
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_WAITOK | M_NULLOK);
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: %ld", 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_WAITOK | M_NULLOK);
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_WAITOK | M_NULLOK);
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 	m = NGI_M(item); /* still associated with item */
358 	M_PREPEND(m, CISCO_HEADER_LEN, MB_DONTWAIT);
359 	if (!m) {
360 		error = ENOBUFS;
361 		goto out;
362 	}
363 	h = mtod(m, struct cisco_header *);
364 	h->address = CISCO_UNICAST;
365 	h->control = 0;
366 
367 	switch (pep->af) {
368 	case AF_INET:		/* Internet Protocol */
369 		h->protocol = htons(ETHERTYPE_IP);
370 		break;
371 	case AF_INET6:
372 		h->protocol = htons(ETHERTYPE_IPV6);
373 		break;
374 	case AF_IPX:		/* Novell IPX Protocol */
375 		h->protocol = htons(ETHERTYPE_IPX);
376 		break;
377 	default:
378 		error = EAFNOSUPPORT;
379 		goto out;
380 	}
381 
382 	/* Send it */
383 	NG_FWD_NEW_DATA(error, item,  sc->downstream.hook, m);
384 	return (error);
385 
386 out:
387 	NG_FREE_ITEM(item);
388 	return (error);
389 }
390 
391 /*
392  * Shutdown node
393  */
394 static int
395 cisco_shutdown(node_p node)
396 {
397 	const sc_p sc = NG_NODE_PRIVATE(node);
398 
399 	NG_NODE_SET_PRIVATE(node, NULL);
400 	NG_NODE_UNREF(sc->node);
401 	kfree(sc, M_NETGRAPH);
402 	return (0);
403 }
404 
405 /*
406  * Disconnection of a hook
407  *
408  * For this type, removal of the last link destroys the node
409  */
410 static int
411 cisco_disconnect(hook_p hook)
412 {
413 	const sc_p sc = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
414 	struct protoent *pep;
415 
416 	/* Check it's not the debug hook */
417 	if ((pep = NG_HOOK_PRIVATE(hook))) {
418 		pep->hook = NULL;
419 		if (pep->af == 0xffff)
420 			/* If it is the downstream hook, stop the timers */
421 			ng_uncallout(&sc->handle, NG_HOOK_NODE(hook));
422 	}
423 
424 	/* If no more hooks, remove the node */
425 	if ((NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0)
426 	&& (NG_NODE_IS_VALID(NG_HOOK_NODE(hook))))
427 		ng_rmnode_self(NG_HOOK_NODE(hook));
428 	return (0);
429 }
430 
431 /*
432  * Receive data
433  */
434 static int
435 cisco_input(sc_p sc, item_p item)
436 {
437 	const struct cisco_header *h;
438 	struct cisco_header hdrbuf;
439 	struct protoent *pep;
440 	struct mbuf *m;
441 	int error = 0;
442 
443 	/* Get data */
444 	m = NGI_M(item);
445 
446 	/* Sanity check header length */
447 	if (m->m_pkthdr.len < sizeof(*h)) {
448 		error = EINVAL;
449 		goto drop;
450 	}
451 
452 	/* Get cisco header */
453 	if (m->m_len >= sizeof(*h))			/* the common case */
454 		h = mtod(m, const struct cisco_header *);
455 	else {
456 		m_copydata(m, 0, sizeof(*h), (caddr_t)&hdrbuf);
457 		h = &hdrbuf;
458 	}
459 	m_adj(m, sizeof(*h));
460 
461 	/* Check header address */
462 	switch (h->address) {
463 	default:		/* Invalid Cisco packet. */
464 		goto drop;
465 	case CISCO_UNICAST:
466 	case CISCO_MULTICAST:
467 		/* Don't check the control field here (RFC 1547). */
468 		switch (ntohs(h->protocol)) {
469 		default:
470 			goto drop;
471 		case CISCO_KEEPALIVE:
472 		    {
473 			const struct cisco_packet *p;
474 			struct cisco_packet pktbuf;
475 
476 			/* Sanity check packet length */
477 			if (m->m_pkthdr.len < sizeof(*p)) {
478 				error = EINVAL;
479 				goto drop;
480 			}
481 
482 			/* Get cisco packet */
483 			if (m->m_len >= sizeof(*p))	/* the common case */
484 				p = mtod(m, const struct cisco_packet *);
485 			else {
486 				m_copydata(m, 0, sizeof(*p), (caddr_t)&pktbuf);
487 				p = &pktbuf;
488 			}
489 
490 			/* Check packet type */
491 			switch (ntohl(p->type)) {
492 			default:
493 				log(LOG_WARNING,
494 				    "cisco: unknown cisco packet type: 0x%lx\n",
495 				       (long)ntohl(p->type));
496 				break;
497 			case CISCO_ADDR_REPLY:
498 				/* Reply on address request, ignore */
499 				break;
500 			case CISCO_KEEPALIVE_REQ:
501 				sc->remote_seq = ntohl(p->par1);
502 				if (sc->local_seq == ntohl(p->par2)) {
503 					sc->local_seq++;
504 					if (sc->seqRetries > 1)
505 						cisco_notify(sc, NGM_LINK_IS_UP);
506 					sc->seqRetries = 0;
507 				}
508 				break;
509 			case CISCO_ADDR_REQ:
510 			    {
511 				struct ng_mesg *msg;
512 				int dummy_error = 0;
513 
514 				/* Ask inet peer for IP address information */
515 				if (sc->inet.hook == NULL)
516 					goto nomsg;
517 				NG_MKMESSAGE(msg, NGM_CISCO_COOKIE,
518 				    NGM_CISCO_GET_IPADDR, 0, M_WAITOK | M_NULLOK);
519 				if (msg == NULL)
520 					goto nomsg;
521 				NG_SEND_MSG_HOOK(dummy_error,
522 				    sc->node, msg, sc->inet.hook, 0);
523 		/*
524 		 * XXX Now maybe we should set a flag telling
525 		 * our receiver to send this message when the response comes in
526 		 * instead of now when the data may be bad.
527 		 */
528 		nomsg:
529 				/* Send reply to peer device */
530 				error = cisco_send(sc, CISCO_ADDR_REPLY,
531 					    ntohl(sc->localip.s_addr),
532 					    ntohl(sc->localmask.s_addr));
533 				break;
534 			    }
535 			}
536 			goto drop;
537 		    }
538 		case ETHERTYPE_IP:
539 			pep = &sc->inet;
540 			break;
541 		case ETHERTYPE_IPV6:
542 			pep = &sc->inet6;
543 			break;
544 		case ETHERTYPE_IPX:
545 			pep = &sc->ipx;
546 			break;
547 		}
548 		break;
549 	}
550 
551 	/* Drop if payload is empty */
552 	if (m->m_pkthdr.len == 0) {
553 		error = EINVAL;
554 		goto drop;
555 	}
556 
557 	/* Send it on */
558 	if (pep->hook == NULL)
559 		goto drop;
560 	NG_FWD_NEW_DATA(error, item, pep->hook, m);
561 	return (error);
562 
563 drop:
564 	NG_FREE_ITEM(item);
565 	return (error);
566 }
567 
568 
569 /*
570  * Send keepalive packets, every 10 seconds.
571  */
572 static void
573 cisco_keepalive(node_p node, hook_p hook, void *arg1, int arg2)
574 {
575 	const sc_p sc = arg1;
576 
577 	cisco_send(sc, CISCO_KEEPALIVE_REQ, sc->local_seq, sc->remote_seq);
578 	if (sc->seqRetries++ > 1)
579 		cisco_notify(sc, NGM_LINK_IS_DOWN);
580 	ng_callout(&sc->handle, node, NULL, (hz * KEEPALIVE_SECS),
581 	    &cisco_keepalive, (void *)sc, 0);
582 }
583 
584 /*
585  * Send Cisco keepalive packet.
586  */
587 static int
588 cisco_send(sc_p sc, int type, long par1, long par2)
589 {
590 	struct cisco_header *h;
591 	struct cisco_packet *ch;
592 	struct mbuf *m;
593 	struct timeval time;
594 	u_long  t;
595 	int     error = 0;
596 
597 	getmicrouptime(&time);
598 
599 	MGETHDR(m, MB_DONTWAIT, MT_DATA);
600 	if (!m)
601 		return (ENOBUFS);
602 
603 	t = time.tv_sec * 1000 + time.tv_usec / 1000;
604 	m->m_pkthdr.len = m->m_len = CISCO_HEADER_LEN + CISCO_PACKET_LEN;
605 	m->m_pkthdr.rcvif = 0;
606 
607 	h = mtod(m, struct cisco_header *);
608 	h->address = CISCO_MULTICAST;
609 	h->control = 0;
610 	h->protocol = htons(CISCO_KEEPALIVE);
611 
612 	ch = (struct cisco_packet *) (h + 1);
613 	ch->type = htonl(type);
614 	ch->par1 = htonl(par1);
615 	ch->par2 = htonl(par2);
616 	ch->rel = -1;
617 	ch->time0 = htons((u_short) (t >> 16));
618 	ch->time1 = htons((u_short) t);
619 
620 	NG_SEND_DATA_ONLY(error, sc->downstream.hook, m);
621 	return (error);
622 }
623 
624 /*
625  * Send linkstate to upstream node.
626  */
627 static void
628 cisco_notify(sc_p sc, uint32_t cmd)
629 {
630 	struct ng_mesg *msg;
631 	int dummy_error = 0;
632 
633 	if (sc->inet.hook == NULL) /* nothing to notify */
634 		return;
635 
636 	NG_MKMESSAGE(msg, NGM_FLOW_COOKIE, cmd, 0, M_WAITOK | M_NULLOK);
637 	if (msg != NULL)
638 		NG_SEND_MSG_HOOK(dummy_error, sc->node, msg, sc->inet.hook, 0);
639 }
640