xref: /freebsd/sys/netgraph/ng_eiface.c (revision 195ebc7e9e4b129de810833791a19dfb4349d6a9)
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  * $FreeBSD$
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 
57 static 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 */
76 struct 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 };
82 typedef struct ng_eiface_private *priv_p;
83 
84 /* Interface methods */
85 static void	ng_eiface_init(void *xsc);
86 static void	ng_eiface_start(struct ifnet *ifp);
87 static int	ng_eiface_ioctl(struct ifnet *ifp, u_long cmd, caddr_t data);
88 #ifdef DEBUG
89 static void	ng_eiface_print_ioctl(struct ifnet *ifp, int cmd, caddr_t data);
90 #endif
91 
92 /* Netgraph methods */
93 static int		ng_eiface_mod_event(module_t, int, void *);
94 static ng_constructor_t	ng_eiface_constructor;
95 static ng_rcvmsg_t	ng_eiface_rcvmsg;
96 static ng_shutdown_t	ng_eiface_rmnode;
97 static ng_newhook_t	ng_eiface_newhook;
98 static ng_rcvdata_t	ng_eiface_rcvdata;
99 static ng_disconnect_t	ng_eiface_disconnect;
100 
101 /* Node type descriptor */
102 static 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 };
114 NETGRAPH_INIT(eiface, &typestruct);
115 
116 static vnet_attach_fn ng_eiface_iattach;
117 static vnet_detach_fn ng_eiface_idetach;
118 
119 #ifdef VIMAGE_GLOBALS
120 static struct unrhdr	*ng_eiface_unit;
121 #endif
122 
123 #ifndef VIMAGE_GLOBALS
124 static vnet_modinfo_t vnet_ng_eiface_modinfo = {
125 	.vmi_id		= VNET_MOD_NG_EIFACE,
126 	.vmi_name	= "ng_eiface",
127 	.vmi_dependson	= VNET_MOD_NETGRAPH,
128 	.vmi_iattach	= ng_eiface_iattach,
129 	.vmi_idetach	= ng_eiface_idetach
130 };
131 #endif
132 
133 /************************************************************************
134 			INTERFACE STUFF
135  ************************************************************************/
136 
137 /*
138  * Process an ioctl for the virtual interface
139  */
140 static int
141 ng_eiface_ioctl(struct ifnet *ifp, u_long command, caddr_t data)
142 {
143 	struct ifreq *const ifr = (struct ifreq *)data;
144 	int s, error = 0;
145 
146 #ifdef DEBUG
147 	ng_eiface_print_ioctl(ifp, command, data);
148 #endif
149 	s = splimp();
150 	switch (command) {
151 
152 	/* These two are mostly handled at a higher layer */
153 	case SIOCSIFADDR:
154 		error = ether_ioctl(ifp, command, data);
155 		break;
156 	case SIOCGIFADDR:
157 		break;
158 
159 	/* Set flags */
160 	case SIOCSIFFLAGS:
161 		/*
162 		 * If the interface is marked up and stopped, then start it.
163 		 * If it is marked down and running, then stop it.
164 		 */
165 		if (ifp->if_flags & IFF_UP) {
166 			if (!(ifp->if_drv_flags & IFF_DRV_RUNNING)) {
167 				ifp->if_drv_flags &= ~(IFF_DRV_OACTIVE);
168 				ifp->if_drv_flags |= IFF_DRV_RUNNING;
169 			}
170 		} else {
171 			if (ifp->if_drv_flags & IFF_DRV_RUNNING)
172 				ifp->if_drv_flags &= ~(IFF_DRV_RUNNING |
173 				    IFF_DRV_OACTIVE);
174 		}
175 		break;
176 
177 	/* Set the interface MTU */
178 	case SIOCSIFMTU:
179 		if (ifr->ifr_mtu > NG_EIFACE_MTU_MAX ||
180 		    ifr->ifr_mtu < NG_EIFACE_MTU_MIN)
181 			error = EINVAL;
182 		else
183 			ifp->if_mtu = ifr->ifr_mtu;
184 		break;
185 
186 	/* Stuff that's not supported */
187 	case SIOCADDMULTI:
188 	case SIOCDELMULTI:
189 		error = 0;
190 		break;
191 	case SIOCSIFPHYS:
192 		error = EOPNOTSUPP;
193 		break;
194 
195 	default:
196 		error = EINVAL;
197 		break;
198 	}
199 	splx(s);
200 	return (error);
201 }
202 
203 static void
204 ng_eiface_init(void *xsc)
205 {
206 	priv_p sc = xsc;
207 	struct ifnet *ifp = sc->ifp;
208 	int s;
209 
210 	s = splimp();
211 
212 	ifp->if_drv_flags |= IFF_DRV_RUNNING;
213 	ifp->if_drv_flags &= ~IFF_DRV_OACTIVE;
214 
215 	splx(s);
216 }
217 
218 /*
219  * We simply relay the packet to the "ether" hook, if it is connected.
220  * We have been through the netgraph locking and are guaranteed to
221  * be the only code running in this node at this time.
222  */
223 static void
224 ng_eiface_start2(node_p node, hook_p hook, void *arg1, int arg2)
225 {
226 	struct ifnet *ifp = arg1;
227 	const priv_p priv = (priv_p)ifp->if_softc;
228 	int error = 0;
229 	struct mbuf *m;
230 
231 	/* Check interface flags */
232 
233 	if (!((ifp->if_flags & IFF_UP) &&
234 	    (ifp->if_drv_flags & IFF_DRV_RUNNING)))
235 		return;
236 
237 	for (;;) {
238 		/*
239 		 * Grab a packet to transmit.
240 		 */
241 		IF_DEQUEUE(&ifp->if_snd, m);
242 
243 		/* If there's nothing to send, break. */
244 		if (m == NULL)
245 			break;
246 
247 		/*
248 		 * Berkeley packet filter.
249 		 * Pass packet to bpf if there is a listener.
250 		 * XXX is this safe? locking?
251 		 */
252 		BPF_MTAP(ifp, m);
253 
254 		if (ifp->if_flags & IFF_MONITOR) {
255 			ifp->if_ipackets++;
256 			m_freem(m);
257 			continue;
258 		}
259 
260 		/*
261 		 * Send packet; if hook is not connected, mbuf will get
262 		 * freed.
263 		 */
264 		NG_SEND_DATA_ONLY(error, priv->ether, m);
265 
266 		/* Update stats */
267 		if (error == 0)
268 			ifp->if_opackets++;
269 		else
270 			ifp->if_oerrors++;
271 	}
272 
273 	ifp->if_drv_flags &= ~IFF_DRV_OACTIVE;
274 
275 	return;
276 }
277 
278 /*
279  * This routine is called to deliver a packet out the interface.
280  * We simply queue the netgraph version to be called when netgraph locking
281  * allows it to happen.
282  * Until we know what the rest of the networking code is doing for
283  * locking, we don't know how we will interact with it.
284  * Take comfort from the fact that the ifnet struct is part of our
285  * private info and can't go away while we are queued.
286  * [Though we don't know it is still there now....]
287  * it is possible we don't gain anything from this because
288  * we would like to get the mbuf and queue it as data
289  * somehow, but we can't and if we did would we solve anything?
290  */
291 static void
292 ng_eiface_start(struct ifnet *ifp)
293 {
294 
295 	const priv_p priv = (priv_p)ifp->if_softc;
296 
297 	/* Don't do anything if output is active */
298 	if (ifp->if_drv_flags & IFF_DRV_OACTIVE)
299 		return;
300 
301 	ifp->if_drv_flags |= IFF_DRV_OACTIVE;
302 
303 	if (ng_send_fn(priv->node, NULL, &ng_eiface_start2, ifp, 0) != 0)
304 		ifp->if_drv_flags &= ~IFF_DRV_OACTIVE;
305 }
306 
307 #ifdef DEBUG
308 /*
309  * Display an ioctl to the virtual interface
310  */
311 
312 static void
313 ng_eiface_print_ioctl(struct ifnet *ifp, int command, caddr_t data)
314 {
315 	char *str;
316 
317 	switch (command & IOC_DIRMASK) {
318 	case IOC_VOID:
319 		str = "IO";
320 		break;
321 	case IOC_OUT:
322 		str = "IOR";
323 		break;
324 	case IOC_IN:
325 		str = "IOW";
326 		break;
327 	case IOC_INOUT:
328 		str = "IORW";
329 		break;
330 	default:
331 		str = "IO??";
332 	}
333 	log(LOG_DEBUG, "%s: %s('%c', %d, char[%d])\n",
334 	    ifp->if_xname,
335 	    str,
336 	    IOCGROUP(command),
337 	    command & 0xff,
338 	    IOCPARM_LEN(command));
339 }
340 #endif /* DEBUG */
341 
342 /************************************************************************
343 			NETGRAPH NODE STUFF
344  ************************************************************************/
345 
346 /*
347  * Constructor for a node
348  */
349 static int
350 ng_eiface_constructor(node_p node)
351 {
352 	INIT_VNET_NETGRAPH(curvnet);
353 	struct ifnet *ifp;
354 	priv_p priv;
355 	u_char eaddr[6] = {0,0,0,0,0,0};
356 
357 	/* Allocate node and interface private structures */
358 	priv = malloc(sizeof(*priv), M_NETGRAPH, M_NOWAIT | M_ZERO);
359 	if (priv == NULL)
360 		return (ENOMEM);
361 
362 	ifp = priv->ifp = if_alloc(IFT_ETHER);
363 	if (ifp == NULL) {
364 		free(priv, M_NETGRAPH);
365 		return (ENOSPC);
366 	}
367 
368 	/* Link them together */
369 	ifp->if_softc = priv;
370 
371 	/* Get an interface unit number */
372 	priv->unit = alloc_unr(V_ng_eiface_unit);
373 
374 	/* Link together node and private info */
375 	NG_NODE_SET_PRIVATE(node, priv);
376 	priv->node = node;
377 
378 	/* Initialize interface structure */
379 	if_initname(ifp, NG_EIFACE_EIFACE_NAME, priv->unit);
380 	ifp->if_init = ng_eiface_init;
381 	ifp->if_output = ether_output;
382 	ifp->if_start = ng_eiface_start;
383 	ifp->if_ioctl = ng_eiface_ioctl;
384 	ifp->if_watchdog = NULL;
385 	ifp->if_snd.ifq_maxlen = IFQ_MAXLEN;
386 	ifp->if_flags = (IFF_SIMPLEX | IFF_BROADCAST | IFF_MULTICAST);
387 
388 #if 0
389 	/* Give this node name */
390 	bzero(ifname, sizeof(ifname));
391 	sprintf(ifname, "if%s", ifp->if_xname);
392 	(void)ng_name_node(node, ifname);
393 #endif
394 
395 	/* Attach the interface */
396 	ether_ifattach(ifp, eaddr);
397 
398 	/* Done */
399 	return (0);
400 }
401 
402 /*
403  * Give our ok for a hook to be added
404  */
405 static int
406 ng_eiface_newhook(node_p node, hook_p hook, const char *name)
407 {
408 	priv_p priv = NG_NODE_PRIVATE(node);
409 	struct ifnet *ifp = priv->ifp;
410 
411 	if (strcmp(name, NG_EIFACE_HOOK_ETHER))
412 		return (EPFNOSUPPORT);
413 	if (priv->ether != NULL)
414 		return (EISCONN);
415 	priv->ether = hook;
416 	NG_HOOK_SET_PRIVATE(hook, &priv->ether);
417 
418 	if_link_state_change(ifp, LINK_STATE_UP);
419 
420 	return (0);
421 }
422 
423 /*
424  * Receive a control message
425  */
426 static int
427 ng_eiface_rcvmsg(node_p node, item_p item, hook_p lasthook)
428 {
429 	const priv_p priv = NG_NODE_PRIVATE(node);
430 	struct ifnet *const ifp = priv->ifp;
431 	struct ng_mesg *resp = NULL;
432 	int error = 0;
433 	struct ng_mesg *msg;
434 
435 	NGI_GET_MSG(item, msg);
436 	switch (msg->header.typecookie) {
437 	case NGM_EIFACE_COOKIE:
438 		switch (msg->header.cmd) {
439 
440 		case NGM_EIFACE_SET:
441 		    {
442 			if (msg->header.arglen != ETHER_ADDR_LEN) {
443 				error = EINVAL;
444 				break;
445 			}
446 			error = if_setlladdr(priv->ifp,
447 			    (u_char *)msg->data, ETHER_ADDR_LEN);
448 			break;
449 		    }
450 
451 		case NGM_EIFACE_GET_IFNAME:
452 			NG_MKRESPONSE(resp, msg, IFNAMSIZ, M_NOWAIT);
453 			if (resp == NULL) {
454 				error = ENOMEM;
455 				break;
456 			}
457 			strlcpy(resp->data, ifp->if_xname, IFNAMSIZ);
458 			break;
459 
460 		case NGM_EIFACE_GET_IFADDRS:
461 		    {
462 			struct ifaddr *ifa;
463 			caddr_t ptr;
464 			int buflen;
465 
466 			/* Determine size of response and allocate it */
467 			buflen = 0;
468 			IF_ADDR_LOCK(ifp);
469 			TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link)
470 				buflen += SA_SIZE(ifa->ifa_addr);
471 			NG_MKRESPONSE(resp, msg, buflen, M_NOWAIT);
472 			if (resp == NULL) {
473 				IF_ADDR_UNLOCK(ifp);
474 				error = ENOMEM;
475 				break;
476 			}
477 
478 			/* Add addresses */
479 			ptr = resp->data;
480 			TAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
481 				const int len = SA_SIZE(ifa->ifa_addr);
482 
483 				if (buflen < len) {
484 					log(LOG_ERR, "%s: len changed?\n",
485 					    ifp->if_xname);
486 					break;
487 				}
488 				bcopy(ifa->ifa_addr, ptr, len);
489 				ptr += len;
490 				buflen -= len;
491 			}
492 			IF_ADDR_UNLOCK(ifp);
493 			break;
494 		    }
495 
496 		default:
497 			error = EINVAL;
498 			break;
499 		} /* end of inner switch() */
500 		break;
501 	case NGM_FLOW_COOKIE:
502 		switch (msg->header.cmd) {
503 		case NGM_LINK_IS_UP:
504 			if_link_state_change(ifp, LINK_STATE_UP);
505 			break;
506 		case NGM_LINK_IS_DOWN:
507 			if_link_state_change(ifp, LINK_STATE_DOWN);
508 			break;
509 		default:
510 			break;
511 		}
512 		break;
513 	default:
514 		error = EINVAL;
515 		break;
516 	}
517 	NG_RESPOND_MSG(error, node, item, resp);
518 	NG_FREE_MSG(msg);
519 	return (error);
520 }
521 
522 /*
523  * Receive data from a hook. Pass the packet to the ether_input routine.
524  */
525 static int
526 ng_eiface_rcvdata(hook_p hook, item_p item)
527 {
528 	const priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
529 	struct ifnet *const ifp = priv->ifp;
530 	struct mbuf *m;
531 
532 	NGI_GET_M(item, m);
533 	NG_FREE_ITEM(item);
534 
535 	if (!((ifp->if_flags & IFF_UP) &&
536 	    (ifp->if_drv_flags & IFF_DRV_RUNNING))) {
537 		NG_FREE_M(m);
538 		return (ENETDOWN);
539 	}
540 
541 	if (m->m_len < ETHER_HDR_LEN) {
542 		m = m_pullup(m, ETHER_HDR_LEN);
543 		if (m == NULL)
544 			return (EINVAL);
545 	}
546 
547 	/* Note receiving interface */
548 	m->m_pkthdr.rcvif = ifp;
549 
550 	/* Update interface stats */
551 	ifp->if_ipackets++;
552 
553 	(*ifp->if_input)(ifp, m);
554 
555 	/* Done */
556 	return (0);
557 }
558 
559 /*
560  * Shutdown processing.
561  */
562 static int
563 ng_eiface_rmnode(node_p node)
564 {
565 	INIT_VNET_NETGRAPH(curvnet);
566 	const priv_p priv = NG_NODE_PRIVATE(node);
567 	struct ifnet *const ifp = priv->ifp;
568 
569 	/*
570 	 * the ifnet may be in a different vnet than the netgraph node,
571 	 * hence we have to change the current vnet context here.
572 	 */
573 	CURVNET_SET_QUIET(ifp->if_vnet);
574 	ether_ifdetach(ifp);
575 	if_free(ifp);
576 	CURVNET_RESTORE();
577 	free_unr(V_ng_eiface_unit, priv->unit);
578 	free(priv, M_NETGRAPH);
579 	NG_NODE_SET_PRIVATE(node, NULL);
580 	NG_NODE_UNREF(node);
581 	return (0);
582 }
583 
584 /*
585  * Hook disconnection
586  */
587 static int
588 ng_eiface_disconnect(hook_p hook)
589 {
590 	const priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
591 
592 	priv->ether = NULL;
593 	return (0);
594 }
595 
596 /*
597  * Handle loading and unloading for this node type.
598  */
599 static int
600 ng_eiface_mod_event(module_t mod, int event, void *data)
601 {
602 	int error = 0;
603 
604 	switch (event) {
605 	case MOD_LOAD:
606 #ifndef VIMAGE_GLOBALS
607 		vnet_mod_register(&vnet_ng_eiface_modinfo);
608 #else
609 		ng_eiface_iattach(NULL);
610 #endif
611 		break;
612 	case MOD_UNLOAD:
613 #ifndef VIMAGE_GLOBALS
614 		vnet_mod_deregister(&vnet_ng_eiface_modinfo);
615 #else
616 		ng_eiface_idetach(NULL);
617 #endif
618 		break;
619 	default:
620 		error = EOPNOTSUPP;
621 		break;
622 	}
623 	return (error);
624 }
625 
626 static int ng_eiface_iattach(const void *unused)
627 {
628 	INIT_VNET_NETGRAPH(curvnet);
629 
630 	V_ng_eiface_unit = new_unrhdr(0, 0xffff, NULL);
631 
632 	return (0);
633 }
634 
635 static int ng_eiface_idetach(const void *unused)
636 {
637 	INIT_VNET_NETGRAPH(curvnet);
638 
639 	delete_unrhdr(V_ng_eiface_unit);
640 
641 	return (0);
642 }
643