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