ng_eiface.c revision 148887 
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 148887 2005-08-09 10:20:02Z rwatson $
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 ifnet	*ifp;		/* per-interface network data */
77	int		unit;		/* Interface unit number */
78	node_p		node;		/* Our netgraph node */
79	hook_p		ether;		/* Hook for ethernet stream */
80};
81typedef struct ng_eiface_private *priv_p;
82
83/* Interface methods */
84static void	ng_eiface_init(void *xsc);
85static void	ng_eiface_start(struct ifnet *ifp);
86static int	ng_eiface_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data);
87#ifdef DEBUG
88static void	ng_eiface_print_ioctl(struct ifnet *ifp, int cmd, caddr_t data);
89#endif
90
91/* Netgraph methods */
92static int		ng_eiface_mod_event(module_t, int, void *);
93static ng_constructor_t	ng_eiface_constructor;
94static ng_rcvmsg_t	ng_eiface_rcvmsg;
95static ng_shutdown_t	ng_eiface_rmnode;
96static ng_newhook_t	ng_eiface_newhook;
97static ng_rcvdata_t	ng_eiface_rcvdata;
98static ng_disconnect_t	ng_eiface_disconnect;
99
100/* Node type descriptor */
101static struct ng_type typestruct = {
102	.version =	NG_ABI_VERSION,
103	.name =		NG_EIFACE_NODE_TYPE,
104	.mod_event =	ng_eiface_mod_event,
105	.constructor =	ng_eiface_constructor,
106	.rcvmsg =	ng_eiface_rcvmsg,
107	.shutdown =	ng_eiface_rmnode,
108	.newhook =	ng_eiface_newhook,
109	.rcvdata =	ng_eiface_rcvdata,
110	.disconnect =	ng_eiface_disconnect,
111	.cmdlist =	ng_eiface_cmdlist
112};
113NETGRAPH_INIT(eiface, &typestruct);
114
115static struct unrhdr	*ng_eiface_unit;
116
117/************************************************************************
118			INTERFACE STUFF
119 ************************************************************************/
120
121/*
122 * Process an ioctl for the virtual interface
123 */
124static int
125ng_eiface_ioctl(struct ifnet *ifp, u_long command, caddr_t data)
126{
127	struct ifreq *const ifr = (struct ifreq *)data;
128	int s, error = 0;
129
130#ifdef DEBUG
131	ng_eiface_print_ioctl(ifp, command, data);
132#endif
133	s = splimp();
134	switch (command) {
135
136	/* These two are mostly handled at a higher layer */
137	case SIOCSIFADDR:
138		error = ether_ioctl(ifp, command, data);
139		break;
140	case SIOCGIFADDR:
141		break;
142
143	/* Set flags */
144	case SIOCSIFFLAGS:
145		/*
146		 * If the interface is marked up and stopped, then start it.
147		 * If it is marked down and running, then stop it.
148		 */
149		if (ifr->ifr_flags & IFF_UP) {
150			if (!(ifp->if_drv_flags & IFF_DRV_RUNNING)) {
151				ifp->if_drv_flags &= ~(IFF_DRV_OACTIVE);
152				ifp->if_drv_flags |= IFF_DRV_RUNNING;
153			}
154		} else {
155			if (ifp->if_drv_flags & IFF_DRV_RUNNING)
156				ifp->if_drv_flags &= ~(IFF_DRV_RUNNING |
157				    IFF_DRV_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_drv_flags |= IFF_DRV_RUNNING;
197	ifp->if_drv_flags &= ~IFF_DRV_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
217	if (!((ifp->if_flags & IFF_UP) &&
218	    (ifp->if_drv_flags & IFF_DRV_RUNNING)))
219		return;
220
221	/* Don't do anything if output is active */
222	if (ifp->if_drv_flags & IFF_DRV_OACTIVE)
223		return;
224
225	ifp->if_drv_flags |= IFF_DRV_OACTIVE;
226
227	/*
228	 * Grab a packet to transmit.
229	 */
230	IF_DEQUEUE(&ifp->if_snd, m);
231
232	/* If there's nothing to send, return. */
233	if (m == NULL) {
234		ifp->if_drv_flags &= ~IFF_DRV_OACTIVE;
235		return;
236	}
237
238	/*
239	 * Berkeley packet filter.
240	 * Pass packet to bpf if there is a listener.
241	 * XXX is this safe? locking?
242	 */
243	BPF_MTAP(ifp, m);
244
245	/* Copy length before the mbuf gets invalidated */
246	len = m->m_pkthdr.len;
247
248	/*
249	 * Send packet; if hook is not connected, mbuf will get
250	 * freed.
251	 */
252	NG_SEND_DATA_ONLY(error, priv->ether, m);
253
254	/* Update stats */
255	if (error == 0) {
256		ifp->if_obytes += len;
257		ifp->if_opackets++;
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	ng_send_fn(priv->node, NULL, &ng_eiface_start2, ifp, 0);
285}
286
287#ifdef DEBUG
288/*
289 * Display an ioctl to the virtual interface
290 */
291
292static void
293ng_eiface_print_ioctl(struct ifnet *ifp, int command, caddr_t data)
294{
295	char *str;
296
297	switch (command & IOC_DIRMASK) {
298	case IOC_VOID:
299		str = "IO";
300		break;
301	case IOC_OUT:
302		str = "IOR";
303		break;
304	case IOC_IN:
305		str = "IOW";
306		break;
307	case IOC_INOUT:
308		str = "IORW";
309		break;
310	default:
311		str = "IO??";
312	}
313	log(LOG_DEBUG, "%s: %s('%c', %d, char[%d])\n",
314	    ifp->if_xname,
315	    str,
316	    IOCGROUP(command),
317	    command & 0xff,
318	    IOCPARM_LEN(command));
319}
320#endif /* DEBUG */
321
322/************************************************************************
323			NETGRAPH NODE STUFF
324 ************************************************************************/
325
326/*
327 * Constructor for a node
328 */
329static int
330ng_eiface_constructor(node_p node)
331{
332	struct ifnet *ifp;
333	priv_p priv;
334	u_char eaddr[6] = {0,0,0,0,0,0};
335
336	/* Allocate node and interface private structures */
337	MALLOC(priv, priv_p, sizeof(*priv), M_NETGRAPH, M_NOWAIT | M_ZERO);
338	if (priv == NULL)
339		return (ENOMEM);
340
341	ifp = priv->ifp = if_alloc(IFT_ETHER);
342	if (ifp == NULL) {
343		free(priv, M_NETGRAPH);
344		return (ENOSPC);
345	}
346
347	/* Link them together */
348	ifp->if_softc = priv;
349
350	/* Get an interface unit number */
351	priv->unit = alloc_unr(ng_eiface_unit);
352
353	/* Link together node and private info */
354	NG_NODE_SET_PRIVATE(node, priv);
355	priv->node = node;
356
357	/* Initialize interface structure */
358	if_initname(ifp, NG_EIFACE_EIFACE_NAME, priv->unit);
359	ifp->if_init = ng_eiface_init;
360	ifp->if_output = ether_output;
361	ifp->if_start = ng_eiface_start;
362	ifp->if_ioctl = ng_eiface_ioctl;
363	ifp->if_watchdog = NULL;
364	ifp->if_snd.ifq_maxlen = IFQ_MAXLEN;
365	ifp->if_flags = (IFF_SIMPLEX | IFF_BROADCAST | IFF_MULTICAST);
366
367#if 0
368	/* Give this node name */
369	bzero(ifname, sizeof(ifname));
370	sprintf(ifname, "if%s", ifp->if_xname);
371	(void)ng_name_node(node, ifname);
372#endif
373
374	/* Attach the interface */
375	ether_ifattach(ifp, eaddr);
376
377	/* Done */
378	return (0);
379}
380
381/*
382 * Give our ok for a hook to be added
383 */
384static int
385ng_eiface_newhook(node_p node, hook_p hook, const char *name)
386{
387	priv_p priv = NG_NODE_PRIVATE(node);
388	struct ifnet *ifp = priv->ifp;
389
390	if (strcmp(name, NG_EIFACE_HOOK_ETHER))
391		return (EPFNOSUPPORT);
392	if (priv->ether != NULL)
393		return (EISCONN);
394	priv->ether = hook;
395	NG_HOOK_SET_PRIVATE(hook, &priv->ether);
396
397	if_link_state_change(ifp, LINK_STATE_UP);
398
399	return (0);
400}
401
402/*
403 * Receive a control message
404 */
405static int
406ng_eiface_rcvmsg(node_p node, item_p item, hook_p lasthook)
407{
408	const priv_p priv = NG_NODE_PRIVATE(node);
409	struct ifnet *const ifp = priv->ifp;
410	struct ng_mesg *resp = NULL;
411	int error = 0;
412	struct ng_mesg *msg;
413
414	NGI_GET_MSG(item, msg);
415	switch (msg->header.typecookie) {
416	case NGM_EIFACE_COOKIE:
417		switch (msg->header.cmd) {
418
419		case NGM_EIFACE_SET:
420		    {
421			struct ether_addr *eaddr;
422			struct ifaddr *ifa;
423			struct sockaddr_dl *sdl;
424
425			if (msg->header.arglen != sizeof(struct ether_addr)) {
426				error = EINVAL;
427				break;
428			}
429			eaddr = (struct ether_addr *)(msg->data);
430			bcopy(eaddr, IFP2ENADDR(priv->ifp),
431			    ETHER_ADDR_LEN);
432
433			/* And put it in the ifaddr list */
434			TAILQ_FOREACH(ifa, &(ifp->if_addrhead), ifa_link) {
435				sdl = (struct sockaddr_dl *)ifa->ifa_addr;
436				if (sdl->sdl_type == IFT_ETHER) {
437					bcopy(IFP2ENADDR(ifp),
438						LLADDR(sdl), ifp->if_addrlen);
439					break;
440				}
441			}
442			break;
443		    }
444
445		case NGM_EIFACE_GET_IFNAME:
446			NG_MKRESPONSE(resp, msg, IFNAMSIZ, M_NOWAIT);
447			if (resp == NULL) {
448				error = ENOMEM;
449				break;
450			}
451			strlcpy(resp->data, ifp->if_xname, IFNAMSIZ);
452			break;
453
454		case NGM_EIFACE_GET_IFADDRS:
455		    {
456			struct ifaddr *ifa;
457			caddr_t ptr;
458			int buflen;
459
460#define SA_SIZE(s)	((s)->sa_len<sizeof(*(s))? sizeof(*(s)):(s)->sa_len)
461
462			/* Determine size of response and allocate it */
463			buflen = 0;
464			TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link)
465				buflen += SA_SIZE(ifa->ifa_addr);
466			NG_MKRESPONSE(resp, msg, buflen, M_NOWAIT);
467			if (resp == NULL) {
468				error = ENOMEM;
469				break;
470			}
471
472			/* Add addresses */
473			ptr = resp->data;
474			TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
475				const int len = SA_SIZE(ifa->ifa_addr);
476
477				if (buflen < len) {
478					log(LOG_ERR, "%s: len changed?\n",
479					    ifp->if_xname);
480					break;
481				}
482				bcopy(ifa->ifa_addr, ptr, len);
483				ptr += len;
484				buflen -= len;
485			}
486			break;
487#undef SA_SIZE
488		    }
489
490		default:
491			error = EINVAL;
492			break;
493		} /* end of inner switch() */
494		break;
495	case NGM_FLOW_COOKIE:
496		switch (msg->header.cmd) {
497		case NGM_LINK_IS_UP:
498			if_link_state_change(ifp, LINK_STATE_UP);
499			break;
500		case NGM_LINK_IS_DOWN:
501			if_link_state_change(ifp, LINK_STATE_DOWN);
502			break;
503		default:
504			break;
505		}
506		break;
507	default:
508		error = EINVAL;
509		break;
510	}
511	NG_RESPOND_MSG(error, node, item, resp);
512	NG_FREE_MSG(msg);
513	return (error);
514}
515
516/*
517 * Receive data from a hook. Pass the packet to the ether_input routine.
518 */
519static int
520ng_eiface_rcvdata(hook_p hook, item_p item)
521{
522	const priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
523	struct ifnet *const ifp = priv->ifp;
524	struct mbuf *m;
525
526	NGI_GET_M(item, m);
527	NG_FREE_ITEM(item);
528
529	if (!((ifp->if_flags & IFF_UP) &&
530	    (ifp->if_drv_flags & IFF_DRV_RUNNING))) {
531		NG_FREE_M(m);
532		return (ENETDOWN);
533	}
534
535	if (m->m_len < ETHER_HDR_LEN) {
536		m = m_pullup(m, ETHER_HDR_LEN);
537		if (m == NULL)
538			return (EINVAL);
539	}
540
541	/* Note receiving interface */
542	m->m_pkthdr.rcvif = ifp;
543
544	/* Update interface stats */
545	ifp->if_ipackets++;
546
547	(*ifp->if_input)(ifp, m);
548
549	/* Done */
550	return (0);
551}
552
553/*
554 * Shutdown processing.
555 */
556static int
557ng_eiface_rmnode(node_p node)
558{
559	const priv_p priv = NG_NODE_PRIVATE(node);
560	struct ifnet *const ifp = priv->ifp;
561
562	ether_ifdetach(ifp);
563	if_free(ifp);
564	free_unr(ng_eiface_unit, priv->unit);
565	FREE(priv, M_NETGRAPH);
566	NG_NODE_SET_PRIVATE(node, NULL);
567	NG_NODE_UNREF(node);
568	return (0);
569}
570
571/*
572 * Hook disconnection
573 */
574static int
575ng_eiface_disconnect(hook_p hook)
576{
577	const priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
578
579	priv->ether = NULL;
580	return (0);
581}
582
583/*
584 * Handle loading and unloading for this node type.
585 */
586static int
587ng_eiface_mod_event(module_t mod, int event, void *data)
588{
589	int error = 0;
590
591	switch (event) {
592	case MOD_LOAD:
593		ng_eiface_unit = new_unrhdr(0, 0xffff, NULL);
594		break;
595	case MOD_UNLOAD:
596		delete_unrhdr(ng_eiface_unit);
597		break;
598	default:
599		error = EOPNOTSUPP;
600		break;
601	}
602	return (error);
603}
604