ng_eiface.c revision 185895 
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 185895 2008-12-10 23:12:39Z zec $
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#include <sys/vimage.h>
42
43#include <net/if.h>
44#include <net/if_types.h>
45#include <net/netisr.h>
46#include <net/route.h>
47
48#include <netgraph/ng_message.h>
49#include <netgraph/netgraph.h>
50#include <netgraph/ng_parse.h>
51#include <netgraph/ng_eiface.h>
52
53#include <net/bpf.h>
54#include <net/ethernet.h>
55#include <net/if_arp.h>
56
57static const struct ng_cmdlist ng_eiface_cmdlist[] = {
58	{
59	  NGM_EIFACE_COOKIE,
60	  NGM_EIFACE_GET_IFNAME,
61	  "getifname",
62	  NULL,
63	  &ng_parse_string_type
64	},
65	{
66	  NGM_EIFACE_COOKIE,
67	  NGM_EIFACE_SET,
68	  "set",
69	  &ng_parse_enaddr_type,
70	  NULL
71	},
72	{ 0 }
73};
74
75/* Node private data */
76struct ng_eiface_private {
77	struct ifnet	*ifp;		/* per-interface network data */
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
116#ifdef VIMAGE_GLOBALS
117static struct unrhdr	*ng_eiface_unit;
118#endif
119
120/************************************************************************
121			INTERFACE STUFF
122 ************************************************************************/
123
124/*
125 * Process an ioctl for the virtual interface
126 */
127static int
128ng_eiface_ioctl(struct ifnet *ifp, u_long command, caddr_t data)
129{
130	struct ifreq *const ifr = (struct ifreq *)data;
131	int s, error = 0;
132
133#ifdef DEBUG
134	ng_eiface_print_ioctl(ifp, command, data);
135#endif
136	s = splimp();
137	switch (command) {
138
139	/* These two are mostly handled at a higher layer */
140	case SIOCSIFADDR:
141		error = ether_ioctl(ifp, command, data);
142		break;
143	case SIOCGIFADDR:
144		break;
145
146	/* Set flags */
147	case SIOCSIFFLAGS:
148		/*
149		 * If the interface is marked up and stopped, then start it.
150		 * If it is marked down and running, then stop it.
151		 */
152		if (ifp->if_flags & IFF_UP) {
153			if (!(ifp->if_drv_flags & IFF_DRV_RUNNING)) {
154				ifp->if_drv_flags &= ~(IFF_DRV_OACTIVE);
155				ifp->if_drv_flags |= IFF_DRV_RUNNING;
156			}
157		} else {
158			if (ifp->if_drv_flags & IFF_DRV_RUNNING)
159				ifp->if_drv_flags &= ~(IFF_DRV_RUNNING |
160				    IFF_DRV_OACTIVE);
161		}
162		break;
163
164	/* Set the interface MTU */
165	case SIOCSIFMTU:
166		if (ifr->ifr_mtu > NG_EIFACE_MTU_MAX ||
167		    ifr->ifr_mtu < NG_EIFACE_MTU_MIN)
168			error = EINVAL;
169		else
170			ifp->if_mtu = ifr->ifr_mtu;
171		break;
172
173	/* Stuff that's not supported */
174	case SIOCADDMULTI:
175	case SIOCDELMULTI:
176		error = 0;
177		break;
178	case SIOCSIFPHYS:
179		error = EOPNOTSUPP;
180		break;
181
182	default:
183		error = EINVAL;
184		break;
185	}
186	splx(s);
187	return (error);
188}
189
190static void
191ng_eiface_init(void *xsc)
192{
193	priv_p sc = xsc;
194	struct ifnet *ifp = sc->ifp;
195	int s;
196
197	s = splimp();
198
199	ifp->if_drv_flags |= IFF_DRV_RUNNING;
200	ifp->if_drv_flags &= ~IFF_DRV_OACTIVE;
201
202	splx(s);
203}
204
205/*
206 * We simply relay the packet to the "ether" hook, if it is connected.
207 * We have been through the netgraph locking and are guaranteed to
208 * be the only code running in this node at this time.
209 */
210static void
211ng_eiface_start2(node_p node, hook_p hook, void *arg1, int arg2)
212{
213	struct ifnet *ifp = arg1;
214	const priv_p priv = (priv_p)ifp->if_softc;
215	int error = 0;
216	struct mbuf *m;
217
218	/* Check interface flags */
219
220	if (!((ifp->if_flags & IFF_UP) &&
221	    (ifp->if_drv_flags & IFF_DRV_RUNNING)))
222		return;
223
224	for (;;) {
225		/*
226		 * Grab a packet to transmit.
227		 */
228		IF_DEQUEUE(&ifp->if_snd, m);
229
230		/* If there's nothing to send, break. */
231		if (m == NULL)
232			break;
233
234		/*
235		 * Berkeley packet filter.
236		 * Pass packet to bpf if there is a listener.
237		 * XXX is this safe? locking?
238		 */
239		BPF_MTAP(ifp, m);
240
241		if (ifp->if_flags & IFF_MONITOR) {
242			ifp->if_ipackets++;
243			m_freem(m);
244			continue;
245		}
246
247		/*
248		 * Send packet; if hook is not connected, mbuf will get
249		 * freed.
250		 */
251		NG_SEND_DATA_ONLY(error, priv->ether, m);
252
253		/* Update stats */
254		if (error == 0)
255			ifp->if_opackets++;
256		else
257			ifp->if_oerrors++;
258	}
259
260	ifp->if_drv_flags &= ~IFF_DRV_OACTIVE;
261
262	return;
263}
264
265/*
266 * This routine is called to deliver a packet out the interface.
267 * We simply queue the netgraph version to be called when netgraph locking
268 * allows it to happen.
269 * Until we know what the rest of the networking code is doing for
270 * locking, we don't know how we will interact with it.
271 * Take comfort from the fact that the ifnet struct is part of our
272 * private info and can't go away while we are queued.
273 * [Though we don't know it is still there now....]
274 * it is possible we don't gain anything from this because
275 * we would like to get the mbuf and queue it as data
276 * somehow, but we can't and if we did would we solve anything?
277 */
278static void
279ng_eiface_start(struct ifnet *ifp)
280{
281
282	const priv_p priv = (priv_p)ifp->if_softc;
283
284	/* Don't do anything if output is active */
285	if (ifp->if_drv_flags & IFF_DRV_OACTIVE)
286		return;
287
288	ifp->if_drv_flags |= IFF_DRV_OACTIVE;
289
290	if (ng_send_fn(priv->node, NULL, &ng_eiface_start2, ifp, 0) != 0)
291		ifp->if_drv_flags &= ~IFF_DRV_OACTIVE;
292}
293
294#ifdef DEBUG
295/*
296 * Display an ioctl to the virtual interface
297 */
298
299static void
300ng_eiface_print_ioctl(struct ifnet *ifp, int command, caddr_t data)
301{
302	char *str;
303
304	switch (command & IOC_DIRMASK) {
305	case IOC_VOID:
306		str = "IO";
307		break;
308	case IOC_OUT:
309		str = "IOR";
310		break;
311	case IOC_IN:
312		str = "IOW";
313		break;
314	case IOC_INOUT:
315		str = "IORW";
316		break;
317	default:
318		str = "IO??";
319	}
320	log(LOG_DEBUG, "%s: %s('%c', %d, char[%d])\n",
321	    ifp->if_xname,
322	    str,
323	    IOCGROUP(command),
324	    command & 0xff,
325	    IOCPARM_LEN(command));
326}
327#endif /* DEBUG */
328
329/************************************************************************
330			NETGRAPH NODE STUFF
331 ************************************************************************/
332
333/*
334 * Constructor for a node
335 */
336static int
337ng_eiface_constructor(node_p node)
338{
339	INIT_VNET_NETGRAPH(curvnet);
340	struct ifnet *ifp;
341	priv_p priv;
342	u_char eaddr[6] = {0,0,0,0,0,0};
343
344	/* Allocate node and interface private structures */
345	priv = malloc(sizeof(*priv), M_NETGRAPH, M_NOWAIT | M_ZERO);
346	if (priv == NULL)
347		return (ENOMEM);
348
349	ifp = priv->ifp = if_alloc(IFT_ETHER);
350	if (ifp == NULL) {
351		free(priv, M_NETGRAPH);
352		return (ENOSPC);
353	}
354
355	/* Link them together */
356	ifp->if_softc = priv;
357
358	/* Get an interface unit number */
359	priv->unit = alloc_unr(V_ng_eiface_unit);
360
361	/* Link together node and private info */
362	NG_NODE_SET_PRIVATE(node, priv);
363	priv->node = node;
364
365	/* Initialize interface structure */
366	if_initname(ifp, NG_EIFACE_EIFACE_NAME, priv->unit);
367	ifp->if_init = ng_eiface_init;
368	ifp->if_output = ether_output;
369	ifp->if_start = ng_eiface_start;
370	ifp->if_ioctl = ng_eiface_ioctl;
371	ifp->if_watchdog = NULL;
372	ifp->if_snd.ifq_maxlen = IFQ_MAXLEN;
373	ifp->if_flags = (IFF_SIMPLEX | IFF_BROADCAST | IFF_MULTICAST);
374
375#if 0
376	/* Give this node name */
377	bzero(ifname, sizeof(ifname));
378	sprintf(ifname, "if%s", ifp->if_xname);
379	(void)ng_name_node(node, ifname);
380#endif
381
382	/* Attach the interface */
383	ether_ifattach(ifp, eaddr);
384
385	/* Done */
386	return (0);
387}
388
389/*
390 * Give our ok for a hook to be added
391 */
392static int
393ng_eiface_newhook(node_p node, hook_p hook, const char *name)
394{
395	priv_p priv = NG_NODE_PRIVATE(node);
396	struct ifnet *ifp = priv->ifp;
397
398	if (strcmp(name, NG_EIFACE_HOOK_ETHER))
399		return (EPFNOSUPPORT);
400	if (priv->ether != NULL)
401		return (EISCONN);
402	priv->ether = hook;
403	NG_HOOK_SET_PRIVATE(hook, &priv->ether);
404
405	if_link_state_change(ifp, LINK_STATE_UP);
406
407	return (0);
408}
409
410/*
411 * Receive a control message
412 */
413static int
414ng_eiface_rcvmsg(node_p node, item_p item, hook_p lasthook)
415{
416	const priv_p priv = NG_NODE_PRIVATE(node);
417	struct ifnet *const ifp = priv->ifp;
418	struct ng_mesg *resp = NULL;
419	int error = 0;
420	struct ng_mesg *msg;
421
422	NGI_GET_MSG(item, msg);
423	switch (msg->header.typecookie) {
424	case NGM_EIFACE_COOKIE:
425		switch (msg->header.cmd) {
426
427		case NGM_EIFACE_SET:
428		    {
429			if (msg->header.arglen != ETHER_ADDR_LEN) {
430				error = EINVAL;
431				break;
432			}
433			error = if_setlladdr(priv->ifp,
434			    (u_char *)msg->data, ETHER_ADDR_LEN);
435			break;
436		    }
437
438		case NGM_EIFACE_GET_IFNAME:
439			NG_MKRESPONSE(resp, msg, IFNAMSIZ, M_NOWAIT);
440			if (resp == NULL) {
441				error = ENOMEM;
442				break;
443			}
444			strlcpy(resp->data, ifp->if_xname, IFNAMSIZ);
445			break;
446
447		case NGM_EIFACE_GET_IFADDRS:
448		    {
449			struct ifaddr *ifa;
450			caddr_t ptr;
451			int buflen;
452
453			/* Determine size of response and allocate it */
454			buflen = 0;
455			TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link)
456				buflen += SA_SIZE(ifa->ifa_addr);
457			NG_MKRESPONSE(resp, msg, buflen, M_NOWAIT);
458			if (resp == NULL) {
459				error = ENOMEM;
460				break;
461			}
462
463			/* Add addresses */
464			ptr = resp->data;
465			TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
466				const int len = SA_SIZE(ifa->ifa_addr);
467
468				if (buflen < len) {
469					log(LOG_ERR, "%s: len changed?\n",
470					    ifp->if_xname);
471					break;
472				}
473				bcopy(ifa->ifa_addr, ptr, len);
474				ptr += len;
475				buflen -= len;
476			}
477			break;
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			if_link_state_change(ifp, LINK_STATE_UP);
489			break;
490		case NGM_LINK_IS_DOWN:
491			if_link_state_change(ifp, LINK_STATE_DOWN);
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) &&
520	    (ifp->if_drv_flags & IFF_DRV_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	INIT_VNET_NETGRAPH(curvnet);
550	const priv_p priv = NG_NODE_PRIVATE(node);
551	struct ifnet *const ifp = priv->ifp;
552
553	/*
554	 * the ifnet may be in a different vnet than the netgraph node,
555	 * hence we have to change the current vnet context here.
556	 */
557	CURVNET_SET_QUIET(ifp->if_vnet);
558	ether_ifdetach(ifp);
559	if_free(ifp);
560	CURVNET_RESTORE();
561	free_unr(V_ng_eiface_unit, priv->unit);
562	free(priv, M_NETGRAPH);
563	NG_NODE_SET_PRIVATE(node, NULL);
564	NG_NODE_UNREF(node);
565	return (0);
566}
567
568/*
569 * Hook disconnection
570 */
571static int
572ng_eiface_disconnect(hook_p hook)
573{
574	const priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
575
576	priv->ether = NULL;
577	return (0);
578}
579
580/*
581 * Handle loading and unloading for this node type.
582 */
583static int
584ng_eiface_mod_event(module_t mod, int event, void *data)
585{
586	int error = 0;
587
588	switch (event) {
589	case MOD_LOAD:
590		V_ng_eiface_unit = new_unrhdr(0, 0xffff, NULL);
591		break;
592	case MOD_UNLOAD:
593		delete_unrhdr(V_ng_eiface_unit);
594		break;
595	default:
596		error = EOPNOTSUPP;
597		break;
598	}
599	return (error);
600}
601