ng_eiface.c revision 143607 
1/*-
2 *
3 * Copyright (c) 1999-2001, Vitaly V Belekhov
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice unmodified, this list of conditions, and the following
11 *    disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 *
28 * $FreeBSD: head/sys/netgraph/ng_eiface.c 143607 2005-03-14 20:49:48Z glebius $
29 */
30
31#include <sys/param.h>
32#include <sys/systm.h>
33#include <sys/errno.h>
34#include <sys/kernel.h>
35#include <sys/malloc.h>
36#include <sys/mbuf.h>
37#include <sys/errno.h>
38#include <sys/sockio.h>
39#include <sys/socket.h>
40#include <sys/syslog.h>
41
42#include <net/if.h>
43#include <net/if_dl.h>
44#include <net/if_types.h>
45#include <net/netisr.h>
46
47#include <netgraph/ng_message.h>
48#include <netgraph/netgraph.h>
49#include <netgraph/ng_parse.h>
50#include <netgraph/ng_eiface.h>
51
52#include <net/bpf.h>
53#include <net/ethernet.h>
54#include <net/if_arp.h>
55
56static const struct ng_cmdlist ng_eiface_cmdlist[] = {
57	{
58	  NGM_EIFACE_COOKIE,
59	  NGM_EIFACE_GET_IFNAME,
60	  "getifname",
61	  NULL,
62	  &ng_parse_string_type
63	},
64	{
65	  NGM_EIFACE_COOKIE,
66	  NGM_EIFACE_SET,
67	  "set",
68	  &ng_parse_enaddr_type,
69	  NULL
70	},
71	{ 0 }
72};
73
74/* Node private data */
75struct ng_eiface_private {
76	struct arpcom	arpcom;		/* per-interface network data */
77	struct ifnet	*ifp;		/* This interface */
78	int		unit;		/* Interface unit number */
79	node_p		node;		/* Our netgraph node */
80	hook_p		ether;		/* Hook for ethernet stream */
81};
82typedef struct ng_eiface_private *priv_p;
83
84/* Interface methods */
85static void	ng_eiface_init(void *xsc);
86static void	ng_eiface_start(struct ifnet *ifp);
87static int	ng_eiface_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data);
88#ifdef DEBUG
89static void	ng_eiface_print_ioctl(struct ifnet *ifp, int cmd, caddr_t data);
90#endif
91
92/* Netgraph methods */
93static int		ng_eiface_mod_event(module_t, int, void *);
94static ng_constructor_t	ng_eiface_constructor;
95static ng_rcvmsg_t	ng_eiface_rcvmsg;
96static ng_shutdown_t	ng_eiface_rmnode;
97static ng_newhook_t	ng_eiface_newhook;
98static ng_rcvdata_t	ng_eiface_rcvdata;
99static ng_disconnect_t	ng_eiface_disconnect;
100
101/* Node type descriptor */
102static struct ng_type typestruct = {
103	.version =	NG_ABI_VERSION,
104	.name =		NG_EIFACE_NODE_TYPE,
105	.mod_event =	ng_eiface_mod_event,
106	.constructor =	ng_eiface_constructor,
107	.rcvmsg =	ng_eiface_rcvmsg,
108	.shutdown =	ng_eiface_rmnode,
109	.newhook =	ng_eiface_newhook,
110	.rcvdata =	ng_eiface_rcvdata,
111	.disconnect =	ng_eiface_disconnect,
112	.cmdlist =	ng_eiface_cmdlist
113};
114NETGRAPH_INIT(eiface, &typestruct);
115
116static struct unrhdr	*ng_eiface_unit;
117
118/************************************************************************
119			INTERFACE STUFF
120 ************************************************************************/
121
122/*
123 * Process an ioctl for the virtual interface
124 */
125static int
126ng_eiface_ioctl(struct ifnet *ifp, u_long command, caddr_t data)
127{
128	struct ifreq *const ifr = (struct ifreq *)data;
129	int s, error = 0;
130
131#ifdef DEBUG
132	ng_eiface_print_ioctl(ifp, command, data);
133#endif
134	s = splimp();
135	switch (command) {
136
137	/* These two are mostly handled at a higher layer */
138	case SIOCSIFADDR:
139		error = ether_ioctl(ifp, command, data);
140		break;
141	case SIOCGIFADDR:
142		break;
143
144	/* Set flags */
145	case SIOCSIFFLAGS:
146		/*
147		 * If the interface is marked up and stopped, then start it.
148		 * If it is marked down and running, then stop it.
149		 */
150		if (ifr->ifr_flags & IFF_UP) {
151			if (!(ifp->if_flags & IFF_RUNNING)) {
152				ifp->if_flags &= ~(IFF_OACTIVE);
153				ifp->if_flags |= IFF_RUNNING;
154			}
155		} else {
156			if (ifp->if_flags & IFF_RUNNING)
157				ifp->if_flags &= ~(IFF_RUNNING | IFF_OACTIVE);
158		}
159		break;
160
161	/* Set the interface MTU */
162	case SIOCSIFMTU:
163		if (ifr->ifr_mtu > NG_EIFACE_MTU_MAX ||
164		    ifr->ifr_mtu < NG_EIFACE_MTU_MIN)
165			error = EINVAL;
166		else
167			ifp->if_mtu = ifr->ifr_mtu;
168		break;
169
170	/* Stuff that's not supported */
171	case SIOCADDMULTI:
172	case SIOCDELMULTI:
173		error = 0;
174		break;
175	case SIOCSIFPHYS:
176		error = EOPNOTSUPP;
177		break;
178
179	default:
180		error = EINVAL;
181		break;
182	}
183	splx(s);
184	return (error);
185}
186
187static void
188ng_eiface_init(void *xsc)
189{
190	priv_p sc = xsc;
191	struct ifnet *ifp = sc->ifp;
192	int s;
193
194	s = splimp();
195
196	ifp->if_flags |= IFF_RUNNING;
197	ifp->if_flags &= ~IFF_OACTIVE;
198
199	splx(s);
200}
201
202/*
203 * We simply relay the packet to the "ether" hook, if it is connected.
204 * We have been through the netgraph locking and are guaranteed to
205 * be the only code running in this node at this time.
206 */
207static void
208ng_eiface_start2(node_p node, hook_p hook, void *arg1, int arg2)
209{
210	struct ifnet *ifp = arg1;
211	const priv_p priv = (priv_p)ifp->if_softc;
212	int len, error = 0;
213	struct mbuf *m;
214
215	/* Check interface flags */
216	if ((ifp->if_flags & (IFF_UP | IFF_RUNNING)) != (IFF_UP | IFF_RUNNING))
217		return;
218
219	/* Don't do anything if output is active */
220	if (ifp->if_flags & IFF_OACTIVE)
221		return;
222
223	ifp->if_flags |= IFF_OACTIVE;
224
225	/*
226	 * Grab a packet to transmit.
227	 */
228	IF_DEQUEUE(&ifp->if_snd, m);
229
230	/* If there's nothing to send, return. */
231	if (m == NULL) {
232		ifp->if_flags &= ~IFF_OACTIVE;
233		return;
234	}
235
236	/*
237	 * Berkeley packet filter.
238	 * Pass packet to bpf if there is a listener.
239	 * XXX is this safe? locking?
240	 */
241	BPF_MTAP(ifp, m);
242
243	/* Copy length before the mbuf gets invalidated */
244	len = m->m_pkthdr.len;
245
246	/*
247	 * Send packet; if hook is not connected, mbuf will get
248	 * freed.
249	 */
250	NG_SEND_DATA_ONLY(error, priv->ether, m);
251
252	/* Update stats */
253	if (error == 0) {
254		ifp->if_obytes += len;
255		ifp->if_opackets++;
256	}
257
258	ifp->if_flags &= ~IFF_OACTIVE;
259
260	return;
261}
262
263/*
264 * This routine is called to deliver a packet out the interface.
265 * We simply queue the netgraph version to be called when netgraph locking
266 * allows it to happen.
267 * Until we know what the rest of the networking code is doing for
268 * locking, we don't know how we will interact with it.
269 * Take comfort from the fact that the ifnet struct is part of our
270 * private info and can't go away while we are queued.
271 * [Though we don't know it is still there now....]
272 * it is possible we don't gain anything from this because
273 * we would like to get the mbuf and queue it as data
274 * somehow, but we can't and if we did would we solve anything?
275 */
276static void
277ng_eiface_start(struct ifnet *ifp)
278{
279
280	const priv_p priv = (priv_p)ifp->if_softc;
281
282	ng_send_fn(priv->node, NULL, &ng_eiface_start2, ifp, 0);
283}
284
285#ifdef DEBUG
286/*
287 * Display an ioctl to the virtual interface
288 */
289
290static void
291ng_eiface_print_ioctl(struct ifnet *ifp, int command, caddr_t data)
292{
293	char *str;
294
295	switch (command & IOC_DIRMASK) {
296	case IOC_VOID:
297		str = "IO";
298		break;
299	case IOC_OUT:
300		str = "IOR";
301		break;
302	case IOC_IN:
303		str = "IOW";
304		break;
305	case IOC_INOUT:
306		str = "IORW";
307		break;
308	default:
309		str = "IO??";
310	}
311	log(LOG_DEBUG, "%s: %s('%c', %d, char[%d])\n",
312	    ifp->if_xname,
313	    str,
314	    IOCGROUP(command),
315	    command & 0xff,
316	    IOCPARM_LEN(command));
317}
318#endif /* DEBUG */
319
320/************************************************************************
321			NETGRAPH NODE STUFF
322 ************************************************************************/
323
324/*
325 * Constructor for a node
326 */
327static int
328ng_eiface_constructor(node_p node)
329{
330	struct ifnet *ifp;
331	priv_p priv;
332
333	/* Allocate node and interface private structures */
334	MALLOC(priv, priv_p, sizeof(*priv), M_NETGRAPH, M_NOWAIT | M_ZERO);
335	if (priv == NULL)
336		return (ENOMEM);
337
338	ifp = &(priv->arpcom.ac_if);
339
340	/* Link them together */
341	ifp->if_softc = priv;
342	priv->ifp = ifp;
343
344	/* Get an interface unit number */
345	priv->unit = alloc_unr(ng_eiface_unit);
346
347	/* Link together node and private info */
348	NG_NODE_SET_PRIVATE(node, priv);
349	priv->node = node;
350
351	/* Initialize interface structure */
352	if_initname(ifp, NG_EIFACE_EIFACE_NAME, priv->unit);
353	ifp->if_init = ng_eiface_init;
354	ifp->if_output = ether_output;
355	ifp->if_start = ng_eiface_start;
356	ifp->if_ioctl = ng_eiface_ioctl;
357	ifp->if_watchdog = NULL;
358	ifp->if_snd.ifq_maxlen = IFQ_MAXLEN;
359	ifp->if_flags = (IFF_SIMPLEX | IFF_BROADCAST | IFF_MULTICAST);
360
361#if 0
362	/* Give this node name */
363	bzero(ifname, sizeof(ifname));
364	sprintf(ifname, "if%s", ifp->if_xname);
365	(void)ng_name_node(node, ifname);
366#endif
367
368	/* Attach the interface */
369	ether_ifattach(ifp, priv->arpcom.ac_enaddr);
370
371	/* Done */
372	return (0);
373}
374
375/*
376 * Give our ok for a hook to be added
377 */
378static int
379ng_eiface_newhook(node_p node, hook_p hook, const char *name)
380{
381	priv_p priv = NG_NODE_PRIVATE(node);
382
383	if (strcmp(name, NG_EIFACE_HOOK_ETHER))
384		return (EPFNOSUPPORT);
385	if (priv->ether != NULL)
386		return (EISCONN);
387	priv->ether = hook;
388	NG_HOOK_SET_PRIVATE(hook, &priv->ether);
389
390	return (0);
391}
392
393/*
394 * Receive a control message
395 */
396static int
397ng_eiface_rcvmsg(node_p node, item_p item, hook_p lasthook)
398{
399	const priv_p priv = NG_NODE_PRIVATE(node);
400	struct ifnet *const ifp = priv->ifp;
401	struct ng_mesg *resp = NULL;
402	int error = 0;
403	struct ng_mesg *msg;
404
405	NGI_GET_MSG(item, msg);
406	switch (msg->header.typecookie) {
407	case NGM_EIFACE_COOKIE:
408		switch (msg->header.cmd) {
409
410		case NGM_EIFACE_SET:
411		    {
412			struct ether_addr *eaddr;
413			struct ifaddr *ifa;
414			struct sockaddr_dl *sdl;
415
416			if (msg->header.arglen != sizeof(struct ether_addr)) {
417				error = EINVAL;
418				break;
419			}
420			eaddr = (struct ether_addr *)(msg->data);
421			bcopy(eaddr, priv->arpcom.ac_enaddr, ETHER_ADDR_LEN);
422
423			/* And put it in the ifaddr list */
424			TAILQ_FOREACH(ifa, &(ifp->if_addrhead), ifa_link) {
425				sdl = (struct sockaddr_dl *)ifa->ifa_addr;
426				if (sdl->sdl_type == IFT_ETHER) {
427					bcopy((IFP2AC(ifp))->ac_enaddr,
428						LLADDR(sdl), ifp->if_addrlen);
429					break;
430				}
431			}
432			break;
433		    }
434
435		case NGM_EIFACE_GET_IFNAME:
436			NG_MKRESPONSE(resp, msg, IFNAMSIZ, M_NOWAIT);
437			if (resp == NULL) {
438				error = ENOMEM;
439				break;
440			}
441			strlcpy(resp->data, ifp->if_xname, IFNAMSIZ);
442			break;
443
444		case NGM_EIFACE_GET_IFADDRS:
445		    {
446			struct ifaddr *ifa;
447			caddr_t ptr;
448			int buflen;
449
450#define SA_SIZE(s)	((s)->sa_len<sizeof(*(s))? sizeof(*(s)):(s)->sa_len)
451
452			/* Determine size of response and allocate it */
453			buflen = 0;
454			TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link)
455				buflen += SA_SIZE(ifa->ifa_addr);
456			NG_MKRESPONSE(resp, msg, buflen, M_NOWAIT);
457			if (resp == NULL) {
458				error = ENOMEM;
459				break;
460			}
461
462			/* Add addresses */
463			ptr = resp->data;
464			TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
465				const int len = SA_SIZE(ifa->ifa_addr);
466
467				if (buflen < len) {
468					log(LOG_ERR, "%s: len changed?\n",
469					    ifp->if_xname);
470					break;
471				}
472				bcopy(ifa->ifa_addr, ptr, len);
473				ptr += len;
474				buflen -= len;
475			}
476			break;
477#undef SA_SIZE
478		    }
479
480		default:
481			error = EINVAL;
482			break;
483		} /* end of inner switch() */
484		break;
485	case NGM_FLOW_COOKIE:
486		switch (msg->header.cmd) {
487		case NGM_LINK_IS_UP:
488			ifp->if_flags |= IFF_RUNNING;
489			break;
490		case NGM_LINK_IS_DOWN:
491			ifp->if_flags &= ~IFF_RUNNING;
492			break;
493		default:
494			break;
495		}
496		break;
497	default:
498		error = EINVAL;
499		break;
500	}
501	NG_RESPOND_MSG(error, node, item, resp);
502	NG_FREE_MSG(msg);
503	return (error);
504}
505
506/*
507 * Receive data from a hook. Pass the packet to the ether_input routine.
508 */
509static int
510ng_eiface_rcvdata(hook_p hook, item_p item)
511{
512	const priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
513	struct ifnet *const ifp = priv->ifp;
514	struct mbuf *m;
515
516	NGI_GET_M(item, m);
517	NG_FREE_ITEM(item);
518
519	if ((ifp->if_flags & (IFF_UP | IFF_RUNNING)) !=
520	    (IFF_UP | IFF_RUNNING)) {
521		NG_FREE_M(m);
522		return (ENETDOWN);
523	}
524
525	if (m->m_len < ETHER_HDR_LEN) {
526		m = m_pullup(m, ETHER_HDR_LEN);
527		if (m == NULL)
528			return (EINVAL);
529	}
530
531	/* Note receiving interface */
532	m->m_pkthdr.rcvif = ifp;
533
534	/* Update interface stats */
535	ifp->if_ipackets++;
536
537	(*ifp->if_input)(ifp, m);
538
539	/* Done */
540	return (0);
541}
542
543/*
544 * Shutdown processing.
545 */
546static int
547ng_eiface_rmnode(node_p node)
548{
549	const priv_p priv = NG_NODE_PRIVATE(node);
550	struct ifnet *const ifp = priv->ifp;
551
552	ether_ifdetach(ifp);
553	free_unr(ng_eiface_unit, priv->unit);
554	FREE(priv, M_NETGRAPH);
555	NG_NODE_SET_PRIVATE(node, NULL);
556	NG_NODE_UNREF(node);
557	return (0);
558}
559
560/*
561 * Hook disconnection
562 */
563static int
564ng_eiface_disconnect(hook_p hook)
565{
566	const priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
567
568	priv->ether = NULL;
569	return (0);
570}
571
572/*
573 * Handle loading and unloading for this node type.
574 */
575static int
576ng_eiface_mod_event(module_t mod, int event, void *data)
577{
578	int error = 0;
579
580	switch (event) {
581	case MOD_LOAD:
582		ng_eiface_unit = new_unrhdr(0, 0xffff, NULL);
583		break;
584	case MOD_UNLOAD:
585		delete_unrhdr(ng_eiface_unit);
586		break;
587	default:
588		error = EOPNOTSUPP;
589		break;
590	}
591	return (error);
592}
593