1
2/*
3 * ng_ether.c
4 *
5 * Copyright (c) 1996-2000 Whistle Communications, Inc.
6 * All rights reserved.
7 *
8 * Subject to the following obligations and disclaimer of warranty, use and
9 * redistribution of this software, in source or object code forms, with or
10 * without modifications are expressly permitted by Whistle Communications;
11 * provided, however, that:
12 * 1. Any and all reproductions of the source or object code must include the
13 * copyright notice above and the following disclaimer of warranties; and
14 * 2. No rights are granted, in any manner or form, to use Whistle
15 * Communications, Inc. trademarks, including the mark "WHISTLE
16 * COMMUNICATIONS" on advertising, endorsements, or otherwise except as
17 * such appears in the above copyright notice or in the software.
18 *
19 * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
20 * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
21 * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
22 * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
23 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
24 * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
25 * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
26 * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
27 * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
28 * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
29 * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
30 * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
31 * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
32 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
33 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
34 * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
35 * OF SUCH DAMAGE.
36 *
37 * Authors: Archie Cobbs <archie@freebsd.org>
38 * Julian Elischer <julian@freebsd.org>
39 *
| 1
2/*
3 * ng_ether.c
4 *
5 * Copyright (c) 1996-2000 Whistle Communications, Inc.
6 * All rights reserved.
7 *
8 * Subject to the following obligations and disclaimer of warranty, use and
9 * redistribution of this software, in source or object code forms, with or
10 * without modifications are expressly permitted by Whistle Communications;
11 * provided, however, that:
12 * 1. Any and all reproductions of the source or object code must include the
13 * copyright notice above and the following disclaimer of warranties; and
14 * 2. No rights are granted, in any manner or form, to use Whistle
15 * Communications, Inc. trademarks, including the mark "WHISTLE
16 * COMMUNICATIONS" on advertising, endorsements, or otherwise except as
17 * such appears in the above copyright notice or in the software.
18 *
19 * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
20 * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
21 * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
22 * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
23 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
24 * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
25 * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
26 * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
27 * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
28 * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
29 * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
30 * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
31 * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
32 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
33 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
34 * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
35 * OF SUCH DAMAGE.
36 *
37 * Authors: Archie Cobbs <archie@freebsd.org>
38 * Julian Elischer <julian@freebsd.org>
39 *
|
41 */
42
43/*
44 * ng_ether(4) netgraph node type
45 */
46
47#include <sys/param.h>
48#include <sys/systm.h>
49#include <sys/kernel.h>
50#include <sys/malloc.h>
51#include <sys/mbuf.h>
52#include <sys/errno.h>
53#include <sys/syslog.h>
54#include <sys/socket.h>
55
56#include <net/if.h>
57#include <net/if_types.h>
58#include <net/if_arp.h>
59#include <net/if_var.h>
60#include <net/ethernet.h>
61
62#include <netgraph/ng_message.h>
63#include <netgraph/netgraph.h>
64#include <netgraph/ng_parse.h>
65#include <netgraph/ng_ether.h>
66
67#define IFP2AC(IFP) ((struct arpcom *)IFP)
68#define IFP2NG(ifp) ((struct ng_node *)((struct arpcom *)(ifp))->ac_netgraph)
69
70/* Per-node private data */
71struct private {
72 struct ifnet *ifp; /* associated interface */
73 hook_p upper; /* upper hook connection */
74 hook_p lower; /* lower OR orphan hook connection */
75 u_char lowerOrphan; /* whether lower is lower or orphan */
76 u_char autoSrcAddr; /* always overwrite source address */
77 u_char promisc; /* promiscuous mode enabled */
78};
79typedef struct private *priv_p;
80
81/* Functional hooks called from if_ethersubr.c */
82static void ng_ether_input(struct ifnet *ifp,
83 struct mbuf **mp, struct ether_header *eh);
84static void ng_ether_input_orphan(struct ifnet *ifp,
85 struct mbuf *m, struct ether_header *eh);
86static int ng_ether_output(struct ifnet *ifp, struct mbuf **mp);
87static void ng_ether_attach(struct ifnet *ifp);
88static void ng_ether_detach(struct ifnet *ifp);
89
90/* Other functions */
91static void ng_ether_input2(node_p node,
92 struct mbuf **mp, struct ether_header *eh);
93static int ng_ether_glueback_header(struct mbuf **mp,
94 struct ether_header *eh);
95static int ng_ether_rcv_lower(node_p node, struct mbuf *m, meta_p meta);
96static int ng_ether_rcv_upper(node_p node, struct mbuf *m, meta_p meta);
97
98/* Netgraph node methods */
99static ng_constructor_t ng_ether_constructor;
100static ng_rcvmsg_t ng_ether_rcvmsg;
101static ng_shutdown_t ng_ether_rmnode;
102static ng_newhook_t ng_ether_newhook;
103static ng_rcvdata_t ng_ether_rcvdata;
104static ng_disconnect_t ng_ether_disconnect;
105static int ng_ether_mod_event(module_t mod, int event, void *data);
106
107/* Parse type for an Ethernet address */
108static ng_parse_t ng_enaddr_parse;
109static ng_unparse_t ng_enaddr_unparse;
110const struct ng_parse_type ng_ether_enaddr_type = {
111 NULL,
112 NULL,
113 NULL,
114 ng_enaddr_parse,
115 ng_enaddr_unparse,
116 NULL, /* no such thing as a "default" EN address */
117 0
118};
119
120/* List of commands and how to convert arguments to/from ASCII */
121static const struct ng_cmdlist ng_ether_cmdlist[] = {
122 {
123 NGM_ETHER_COOKIE,
124 NGM_ETHER_GET_IFNAME,
125 "getifname",
126 NULL,
127 &ng_parse_string_type
128 },
129 {
130 NGM_ETHER_COOKIE,
131 NGM_ETHER_GET_IFINDEX,
132 "getifindex",
133 NULL,
134 &ng_parse_int32_type
135 },
136 {
137 NGM_ETHER_COOKIE,
138 NGM_ETHER_GET_ENADDR,
139 "getenaddr",
140 NULL,
141 &ng_ether_enaddr_type
142 },
143 {
144 NGM_ETHER_COOKIE,
145 NGM_ETHER_SET_ENADDR,
146 "setenaddr",
147 &ng_ether_enaddr_type,
148 NULL
149 },
150 {
151 NGM_ETHER_COOKIE,
152 NGM_ETHER_GET_PROMISC,
153 "getpromisc",
154 NULL,
155 &ng_parse_int32_type
156 },
157 {
158 NGM_ETHER_COOKIE,
159 NGM_ETHER_SET_PROMISC,
160 "setpromisc",
161 &ng_parse_int32_type,
162 NULL
163 },
164 {
165 NGM_ETHER_COOKIE,
166 NGM_ETHER_GET_AUTOSRC,
167 "getautosrc",
168 NULL,
169 &ng_parse_int32_type
170 },
171 {
172 NGM_ETHER_COOKIE,
173 NGM_ETHER_SET_AUTOSRC,
174 "setautosrc",
175 &ng_parse_int32_type,
176 NULL
177 },
178 { 0 }
179};
180
181static struct ng_type ng_ether_typestruct = {
182 NG_VERSION,
183 NG_ETHER_NODE_TYPE,
184 ng_ether_mod_event,
185 ng_ether_constructor,
186 ng_ether_rcvmsg,
187 ng_ether_rmnode,
188 ng_ether_newhook,
189 NULL,
190 NULL,
191 ng_ether_rcvdata,
192 ng_ether_rcvdata,
193 ng_ether_disconnect,
194 ng_ether_cmdlist,
195};
196NETGRAPH_INIT(ether, &ng_ether_typestruct);
197
198/******************************************************************
199 ETHERNET FUNCTION HOOKS
200******************************************************************/
201
202/*
203 * Handle a packet that has come in on an interface. We get to
204 * look at it here before any upper layer protocols do.
205 *
206 * NOTE: this function will get called at splimp()
207 */
208static void
209ng_ether_input(struct ifnet *ifp,
210 struct mbuf **mp, struct ether_header *eh)
211{
212 const node_p node = IFP2NG(ifp);
213 const priv_p priv = node->private;
214
215 /* If "lower" hook not connected, let packet continue */
216 if (priv->lower == NULL || priv->lowerOrphan)
217 return;
218 ng_ether_input2(node, mp, eh);
219}
220
221/*
222 * Handle a packet that has come in on an interface, and which
223 * does not match any of our known protocols (an ``orphan'').
224 *
225 * NOTE: this function will get called at splimp()
226 */
227static void
228ng_ether_input_orphan(struct ifnet *ifp,
229 struct mbuf *m, struct ether_header *eh)
230{
231 const node_p node = IFP2NG(ifp);
232 const priv_p priv = node->private;
233
234 /* If "orphan" hook not connected, let packet continue */
235 if (priv->lower == NULL || !priv->lowerOrphan) {
236 m_freem(m);
237 return;
238 }
239 ng_ether_input2(node, &m, eh);
240 if (m != NULL)
241 m_freem(m);
242}
243
244/*
245 * Handle a packet that has come in on an interface.
246 * The Ethernet header has already been detached from the mbuf,
247 * so we have to put it back.
248 *
249 * NOTE: this function will get called at splimp()
250 */
251static void
252ng_ether_input2(node_p node, struct mbuf **mp, struct ether_header *eh)
253{
254 const priv_p priv = node->private;
255 meta_p meta = NULL;
256 int error;
257
258 /* Glue Ethernet header back on */
259 if ((error = ng_ether_glueback_header(mp, eh)) != 0)
260 return;
261
262 /* Send out lower/orphan hook */
263 (void)ng_queue_data(priv->lower, *mp, meta);
264 *mp = NULL;
265}
266
267/*
268 * Handle a packet that is going out on an interface.
269 * The Ethernet header is already attached to the mbuf.
270 */
271static int
272ng_ether_output(struct ifnet *ifp, struct mbuf **mp)
273{
274 const node_p node = IFP2NG(ifp);
275 const priv_p priv = node->private;
276 meta_p meta = NULL;
277 int error = 0;
278
279 /* If "upper" hook not connected, let packet continue */
280 if (priv->upper == NULL)
281 return (0);
282
283 /* Send it out "upper" hook */
284 NG_SEND_DATA_RET(error, priv->upper, *mp, meta);
285
286 /* If we got a reflected packet back, handle it */
287 if (error == 0 && *mp != NULL) {
288 error = ng_ether_rcv_upper(node, *mp, meta);
289 *mp = NULL;
290 }
291 return (error);
292}
293
294/*
295 * A new Ethernet interface has been attached.
296 * Create a new node for it, etc.
297 */
298static void
299ng_ether_attach(struct ifnet *ifp)
300{
301 char name[IFNAMSIZ + 1];
302 priv_p priv;
303 node_p node;
304
305 /* Create node */
306 KASSERT(!IFP2NG(ifp), ("%s: node already exists?", __FUNCTION__));
307 snprintf(name, sizeof(name), "%s%d", ifp->if_name, ifp->if_unit);
308 if (ng_make_node_common(&ng_ether_typestruct, &node) != 0) {
309 log(LOG_ERR, "%s: can't %s for %s\n",
310 __FUNCTION__, "create node", name);
311 return;
312 }
313
314 /* Allocate private data */
315 MALLOC(priv, priv_p, sizeof(*priv), M_NETGRAPH, M_NOWAIT);
316 if (priv == NULL) {
317 log(LOG_ERR, "%s: can't %s for %s\n",
318 __FUNCTION__, "allocate memory", name);
319 ng_unref(node);
320 return;
321 }
322 bzero(priv, sizeof(*priv));
323 node->private = priv;
324 priv->ifp = ifp;
325 IFP2NG(ifp) = node;
326 priv->autoSrcAddr = 1;
327
328 /* Try to give the node the same name as the interface */
329 if (ng_name_node(node, name) != 0) {
330 log(LOG_WARNING, "%s: can't name node %s\n",
331 __FUNCTION__, name);
332 }
333}
334
335/*
336 * An Ethernet interface is being detached.
337 * Destroy its node.
338 */
339static void
340ng_ether_detach(struct ifnet *ifp)
341{
342 const node_p node = IFP2NG(ifp);
343 priv_p priv;
344
345 if (node == NULL) /* no node (why not?), ignore */
346 return;
347 ng_rmnode(node); /* break all links to other nodes */
348 node->flags |= NG_INVALID;
349 ng_unname(node); /* free name (and its reference) */
350 IFP2NG(ifp) = NULL; /* detach node from interface */
351 priv = node->private; /* free node private info */
352 bzero(priv, sizeof(*priv));
353 FREE(priv, M_NETGRAPH);
354 node->private = NULL;
355 ng_unref(node); /* free node itself */
356}
357
358/*
359 * Optimization for gluing the Ethernet header back onto
360 * the front of an incoming packet.
361 */
362static int
363ng_ether_glueback_header(struct mbuf **mp, struct ether_header *eh)
364{
365 struct mbuf *m = *mp;
366 uintfptr_t room;
367 int error = 0;
368
369 /*
370 * Possibly the header is already on the front.
371 * If this is the case so just move the markers back
372 * to re-include it. We lucked out.
373 * This allows us to avoid a yucky m_pullup
374 * in later nodes if it works.
375 */
376 if (eh == mtod(m, struct ether_header *) - 1) {
377 m->m_len += sizeof(*eh);
378 m->m_data -= sizeof(*eh);
379 m->m_pkthdr.len += sizeof(*eh);
380 goto done;
381 }
382
383 /*
384 * Alternatively there may be room even though
385 * it is stored somewhere else. If so, copy it in.
386 * This only safe because we KNOW that this packet has
387 * just been generated by an ethernet card, so there are
388 * no aliases to the buffer (not so for outgoing packets).
389 * Nearly all ethernet cards will end up producing mbufs
390 * that fall into these cases. So we are not optimizing
391 * contorted cases.
392 */
393 if ((m->m_flags & M_EXT) != 0) {
394 room = mtod(m, caddr_t) - m->m_ext.ext_buf;
395 if (room > m->m_ext.ext_size) /* garbage, fail immediately */
396 room = 0;
397 } else
398 room = mtod(m, caddr_t) - m->m_pktdat;
399
400 /*
401 * If we have room, just copy it and adjust
402 */
403 if (room >= sizeof(*eh)) {
404 m->m_len += sizeof(*eh);
405 m->m_data -= sizeof(*eh);
406 m->m_pkthdr.len += sizeof(*eh);
407 goto copy;
408 }
409
410 /*
411 * Doing anything more is likely to get more
412 * expensive than it's worth..
413 * it's probable that everything else is in one
414 * big lump. The next node will do an m_pullup()
415 * for exactly the amount of data it needs and
416 * hopefully everything after that will not
417 * need one. So let's just use M_PREPEND.
418 */
419 M_PREPEND(m, sizeof (*eh), M_DONTWAIT);
420 if (m == NULL) {
421 error = ENOBUFS;
422 goto done;
423 }
424
425copy:
426 /* Copy header and return (possibly new) mbuf */
427 bcopy((caddr_t)eh, mtod(m, struct ether_header *), sizeof(*eh));
428done:
429 *mp = m;
430 return error;
431}
432
433/******************************************************************
434 NETGRAPH NODE METHODS
435******************************************************************/
436
437/*
438 * It is not possible or allowable to create a node of this type.
439 * Nodes get created when the interface is attached (or, when
440 * this node type's KLD is loaded).
441 */
442static int
443ng_ether_constructor(node_p *nodep)
444{
445 return (EINVAL);
446}
447
448/*
449 * Check for attaching a new hook.
450 */
451static int
452ng_ether_newhook(node_p node, hook_p hook, const char *name)
453{
454 const priv_p priv = node->private;
455 u_char orphan = priv->lowerOrphan;
456 hook_p *hookptr;
457
458 /* Divert hook is an alias for lower */
459 if (strcmp(name, NG_ETHER_HOOK_DIVERT) == 0)
460 name = NG_ETHER_HOOK_LOWER;
461
462 /* Which hook? */
463 if (strcmp(name, NG_ETHER_HOOK_UPPER) == 0)
464 hookptr = &priv->upper;
465 else if (strcmp(name, NG_ETHER_HOOK_LOWER) == 0) {
466 hookptr = &priv->lower;
467 orphan = 0;
468 } else if (strcmp(name, NG_ETHER_HOOK_ORPHAN) == 0) {
469 hookptr = &priv->lower;
470 orphan = 1;
471 } else
472 return (EINVAL);
473
474 /* Check if already connected (shouldn't be, but doesn't hurt) */
475 if (*hookptr != NULL)
476 return (EISCONN);
477
478 /* OK */
479 *hookptr = hook;
480 priv->lowerOrphan = orphan;
481 return (0);
482}
483
484/*
485 * Receive an incoming control message.
486 */
487static int
488ng_ether_rcvmsg(node_p node, struct ng_mesg *msg, const char *retaddr,
489 struct ng_mesg **rptr, hook_p lasthook)
490{
491 const priv_p priv = node->private;
492 struct ng_mesg *resp = NULL;
493 int error = 0;
494
495 switch (msg->header.typecookie) {
496 case NGM_ETHER_COOKIE:
497 switch (msg->header.cmd) {
498 case NGM_ETHER_GET_IFNAME:
499 NG_MKRESPONSE(resp, msg, IFNAMSIZ + 1, M_NOWAIT);
500 if (resp == NULL) {
501 error = ENOMEM;
502 break;
503 }
504 snprintf(resp->data, IFNAMSIZ + 1,
505 "%s%d", priv->ifp->if_name, priv->ifp->if_unit);
506 break;
507 case NGM_ETHER_GET_IFINDEX:
508 NG_MKRESPONSE(resp, msg, sizeof(u_int32_t), M_NOWAIT);
509 if (resp == NULL) {
510 error = ENOMEM;
511 break;
512 }
513 *((u_int32_t *)resp->data) = priv->ifp->if_index;
514 break;
515 case NGM_ETHER_GET_ENADDR:
516 NG_MKRESPONSE(resp, msg, ETHER_ADDR_LEN, M_NOWAIT);
517 if (resp == NULL) {
518 error = ENOMEM;
519 break;
520 }
521 bcopy((IFP2AC(priv->ifp))->ac_enaddr,
522 resp->data, ETHER_ADDR_LEN);
523 break;
524 case NGM_ETHER_SET_ENADDR:
525 {
526 if (msg->header.arglen != ETHER_ADDR_LEN) {
527 error = EINVAL;
528 break;
529 }
530 error = if_setlladdr(priv->ifp,
531 (u_char *)msg->data, ETHER_ADDR_LEN);
532 break;
533 }
534 case NGM_ETHER_GET_PROMISC:
535 NG_MKRESPONSE(resp, msg, sizeof(u_int32_t), M_NOWAIT);
536 if (resp == NULL) {
537 error = ENOMEM;
538 break;
539 }
540 *((u_int32_t *)resp->data) = priv->promisc;
541 break;
542 case NGM_ETHER_SET_PROMISC:
543 {
544 u_char want;
545
546 if (msg->header.arglen != sizeof(u_int32_t)) {
547 error = EINVAL;
548 break;
549 }
550 want = !!*((u_int32_t *)msg->data);
551 if (want ^ priv->promisc) {
552 if ((error = ifpromisc(priv->ifp, want)) != 0)
553 break;
554 priv->promisc = want;
555 }
556 break;
557 }
558 case NGM_ETHER_GET_AUTOSRC:
559 NG_MKRESPONSE(resp, msg, sizeof(u_int32_t), M_NOWAIT);
560 if (resp == NULL) {
561 error = ENOMEM;
562 break;
563 }
564 *((u_int32_t *)resp->data) = priv->autoSrcAddr;
565 break;
566 case NGM_ETHER_SET_AUTOSRC:
567 if (msg->header.arglen != sizeof(u_int32_t)) {
568 error = EINVAL;
569 break;
570 }
571 priv->autoSrcAddr = !!*((u_int32_t *)msg->data);
572 break;
573 default:
574 error = EINVAL;
575 break;
576 }
577 break;
578 default:
579 error = EINVAL;
580 break;
581 }
582 if (rptr)
583 *rptr = resp;
584 else if (resp != NULL)
585 FREE(resp, M_NETGRAPH);
586 FREE(msg, M_NETGRAPH);
587 return (error);
588}
589
590/*
591 * Receive data on a hook.
592 */
593static int
594ng_ether_rcvdata(hook_p hook, struct mbuf *m, meta_p meta,
595 struct mbuf **ret_m, meta_p *ret_meta)
596{
597 const node_p node = hook->node;
598 const priv_p priv = node->private;
599
600 if (hook == priv->lower)
601 return ng_ether_rcv_lower(node, m, meta);
602 if (hook == priv->upper)
603 return ng_ether_rcv_upper(node, m, meta);
604 panic("%s: weird hook", __FUNCTION__);
605}
606
607/*
608 * Handle an mbuf received on the "lower" hook.
609 */
610static int
611ng_ether_rcv_lower(node_p node, struct mbuf *m, meta_p meta)
612{
613 const priv_p priv = node->private;
614
615 /* Make sure header is fully pulled up */
616 if (m->m_pkthdr.len < sizeof(struct ether_header)) {
617 NG_FREE_DATA(m, meta);
618 return (EINVAL);
619 }
620 if (m->m_len < sizeof(struct ether_header)
621 && (m = m_pullup(m, sizeof(struct ether_header))) == NULL) {
622 NG_FREE_META(meta);
623 return (ENOBUFS);
624 }
625
626 /* Drop in the MAC address if desired */
627 if (priv->autoSrcAddr) {
628 bcopy((IFP2AC(priv->ifp))->ac_enaddr,
629 mtod(m, struct ether_header *)->ether_shost,
630 ETHER_ADDR_LEN);
631 }
632
633 /* Send it on its way */
634 NG_FREE_META(meta);
635 return ether_output_frame(priv->ifp, m);
636}
637
638/*
639 * Handle an mbuf received on the "upper" hook.
640 */
641static int
642ng_ether_rcv_upper(node_p node, struct mbuf *m, meta_p meta)
643{
644 const priv_p priv = node->private;
645 struct ether_header *eh;
646
647 /* Check length and pull off header */
648 if (m->m_pkthdr.len < sizeof(*eh)) {
649 NG_FREE_DATA(m, meta);
650 return (EINVAL);
651 }
652 if (m->m_len < sizeof(*eh) && (m = m_pullup(m, sizeof(*eh))) == NULL) {
653 NG_FREE_META(meta);
654 return (ENOBUFS);
655 }
656 eh = mtod(m, struct ether_header *);
657 m->m_data += sizeof(*eh);
658 m->m_len -= sizeof(*eh);
659 m->m_pkthdr.len -= sizeof(*eh);
| 41 */
42
43/*
44 * ng_ether(4) netgraph node type
45 */
46
47#include <sys/param.h>
48#include <sys/systm.h>
49#include <sys/kernel.h>
50#include <sys/malloc.h>
51#include <sys/mbuf.h>
52#include <sys/errno.h>
53#include <sys/syslog.h>
54#include <sys/socket.h>
55
56#include <net/if.h>
57#include <net/if_types.h>
58#include <net/if_arp.h>
59#include <net/if_var.h>
60#include <net/ethernet.h>
61
62#include <netgraph/ng_message.h>
63#include <netgraph/netgraph.h>
64#include <netgraph/ng_parse.h>
65#include <netgraph/ng_ether.h>
66
67#define IFP2AC(IFP) ((struct arpcom *)IFP)
68#define IFP2NG(ifp) ((struct ng_node *)((struct arpcom *)(ifp))->ac_netgraph)
69
70/* Per-node private data */
71struct private {
72 struct ifnet *ifp; /* associated interface */
73 hook_p upper; /* upper hook connection */
74 hook_p lower; /* lower OR orphan hook connection */
75 u_char lowerOrphan; /* whether lower is lower or orphan */
76 u_char autoSrcAddr; /* always overwrite source address */
77 u_char promisc; /* promiscuous mode enabled */
78};
79typedef struct private *priv_p;
80
81/* Functional hooks called from if_ethersubr.c */
82static void ng_ether_input(struct ifnet *ifp,
83 struct mbuf **mp, struct ether_header *eh);
84static void ng_ether_input_orphan(struct ifnet *ifp,
85 struct mbuf *m, struct ether_header *eh);
86static int ng_ether_output(struct ifnet *ifp, struct mbuf **mp);
87static void ng_ether_attach(struct ifnet *ifp);
88static void ng_ether_detach(struct ifnet *ifp);
89
90/* Other functions */
91static void ng_ether_input2(node_p node,
92 struct mbuf **mp, struct ether_header *eh);
93static int ng_ether_glueback_header(struct mbuf **mp,
94 struct ether_header *eh);
95static int ng_ether_rcv_lower(node_p node, struct mbuf *m, meta_p meta);
96static int ng_ether_rcv_upper(node_p node, struct mbuf *m, meta_p meta);
97
98/* Netgraph node methods */
99static ng_constructor_t ng_ether_constructor;
100static ng_rcvmsg_t ng_ether_rcvmsg;
101static ng_shutdown_t ng_ether_rmnode;
102static ng_newhook_t ng_ether_newhook;
103static ng_rcvdata_t ng_ether_rcvdata;
104static ng_disconnect_t ng_ether_disconnect;
105static int ng_ether_mod_event(module_t mod, int event, void *data);
106
107/* Parse type for an Ethernet address */
108static ng_parse_t ng_enaddr_parse;
109static ng_unparse_t ng_enaddr_unparse;
110const struct ng_parse_type ng_ether_enaddr_type = {
111 NULL,
112 NULL,
113 NULL,
114 ng_enaddr_parse,
115 ng_enaddr_unparse,
116 NULL, /* no such thing as a "default" EN address */
117 0
118};
119
120/* List of commands and how to convert arguments to/from ASCII */
121static const struct ng_cmdlist ng_ether_cmdlist[] = {
122 {
123 NGM_ETHER_COOKIE,
124 NGM_ETHER_GET_IFNAME,
125 "getifname",
126 NULL,
127 &ng_parse_string_type
128 },
129 {
130 NGM_ETHER_COOKIE,
131 NGM_ETHER_GET_IFINDEX,
132 "getifindex",
133 NULL,
134 &ng_parse_int32_type
135 },
136 {
137 NGM_ETHER_COOKIE,
138 NGM_ETHER_GET_ENADDR,
139 "getenaddr",
140 NULL,
141 &ng_ether_enaddr_type
142 },
143 {
144 NGM_ETHER_COOKIE,
145 NGM_ETHER_SET_ENADDR,
146 "setenaddr",
147 &ng_ether_enaddr_type,
148 NULL
149 },
150 {
151 NGM_ETHER_COOKIE,
152 NGM_ETHER_GET_PROMISC,
153 "getpromisc",
154 NULL,
155 &ng_parse_int32_type
156 },
157 {
158 NGM_ETHER_COOKIE,
159 NGM_ETHER_SET_PROMISC,
160 "setpromisc",
161 &ng_parse_int32_type,
162 NULL
163 },
164 {
165 NGM_ETHER_COOKIE,
166 NGM_ETHER_GET_AUTOSRC,
167 "getautosrc",
168 NULL,
169 &ng_parse_int32_type
170 },
171 {
172 NGM_ETHER_COOKIE,
173 NGM_ETHER_SET_AUTOSRC,
174 "setautosrc",
175 &ng_parse_int32_type,
176 NULL
177 },
178 { 0 }
179};
180
181static struct ng_type ng_ether_typestruct = {
182 NG_VERSION,
183 NG_ETHER_NODE_TYPE,
184 ng_ether_mod_event,
185 ng_ether_constructor,
186 ng_ether_rcvmsg,
187 ng_ether_rmnode,
188 ng_ether_newhook,
189 NULL,
190 NULL,
191 ng_ether_rcvdata,
192 ng_ether_rcvdata,
193 ng_ether_disconnect,
194 ng_ether_cmdlist,
195};
196NETGRAPH_INIT(ether, &ng_ether_typestruct);
197
198/******************************************************************
199 ETHERNET FUNCTION HOOKS
200******************************************************************/
201
202/*
203 * Handle a packet that has come in on an interface. We get to
204 * look at it here before any upper layer protocols do.
205 *
206 * NOTE: this function will get called at splimp()
207 */
208static void
209ng_ether_input(struct ifnet *ifp,
210 struct mbuf **mp, struct ether_header *eh)
211{
212 const node_p node = IFP2NG(ifp);
213 const priv_p priv = node->private;
214
215 /* If "lower" hook not connected, let packet continue */
216 if (priv->lower == NULL || priv->lowerOrphan)
217 return;
218 ng_ether_input2(node, mp, eh);
219}
220
221/*
222 * Handle a packet that has come in on an interface, and which
223 * does not match any of our known protocols (an ``orphan'').
224 *
225 * NOTE: this function will get called at splimp()
226 */
227static void
228ng_ether_input_orphan(struct ifnet *ifp,
229 struct mbuf *m, struct ether_header *eh)
230{
231 const node_p node = IFP2NG(ifp);
232 const priv_p priv = node->private;
233
234 /* If "orphan" hook not connected, let packet continue */
235 if (priv->lower == NULL || !priv->lowerOrphan) {
236 m_freem(m);
237 return;
238 }
239 ng_ether_input2(node, &m, eh);
240 if (m != NULL)
241 m_freem(m);
242}
243
244/*
245 * Handle a packet that has come in on an interface.
246 * The Ethernet header has already been detached from the mbuf,
247 * so we have to put it back.
248 *
249 * NOTE: this function will get called at splimp()
250 */
251static void
252ng_ether_input2(node_p node, struct mbuf **mp, struct ether_header *eh)
253{
254 const priv_p priv = node->private;
255 meta_p meta = NULL;
256 int error;
257
258 /* Glue Ethernet header back on */
259 if ((error = ng_ether_glueback_header(mp, eh)) != 0)
260 return;
261
262 /* Send out lower/orphan hook */
263 (void)ng_queue_data(priv->lower, *mp, meta);
264 *mp = NULL;
265}
266
267/*
268 * Handle a packet that is going out on an interface.
269 * The Ethernet header is already attached to the mbuf.
270 */
271static int
272ng_ether_output(struct ifnet *ifp, struct mbuf **mp)
273{
274 const node_p node = IFP2NG(ifp);
275 const priv_p priv = node->private;
276 meta_p meta = NULL;
277 int error = 0;
278
279 /* If "upper" hook not connected, let packet continue */
280 if (priv->upper == NULL)
281 return (0);
282
283 /* Send it out "upper" hook */
284 NG_SEND_DATA_RET(error, priv->upper, *mp, meta);
285
286 /* If we got a reflected packet back, handle it */
287 if (error == 0 && *mp != NULL) {
288 error = ng_ether_rcv_upper(node, *mp, meta);
289 *mp = NULL;
290 }
291 return (error);
292}
293
294/*
295 * A new Ethernet interface has been attached.
296 * Create a new node for it, etc.
297 */
298static void
299ng_ether_attach(struct ifnet *ifp)
300{
301 char name[IFNAMSIZ + 1];
302 priv_p priv;
303 node_p node;
304
305 /* Create node */
306 KASSERT(!IFP2NG(ifp), ("%s: node already exists?", __FUNCTION__));
307 snprintf(name, sizeof(name), "%s%d", ifp->if_name, ifp->if_unit);
308 if (ng_make_node_common(&ng_ether_typestruct, &node) != 0) {
309 log(LOG_ERR, "%s: can't %s for %s\n",
310 __FUNCTION__, "create node", name);
311 return;
312 }
313
314 /* Allocate private data */
315 MALLOC(priv, priv_p, sizeof(*priv), M_NETGRAPH, M_NOWAIT);
316 if (priv == NULL) {
317 log(LOG_ERR, "%s: can't %s for %s\n",
318 __FUNCTION__, "allocate memory", name);
319 ng_unref(node);
320 return;
321 }
322 bzero(priv, sizeof(*priv));
323 node->private = priv;
324 priv->ifp = ifp;
325 IFP2NG(ifp) = node;
326 priv->autoSrcAddr = 1;
327
328 /* Try to give the node the same name as the interface */
329 if (ng_name_node(node, name) != 0) {
330 log(LOG_WARNING, "%s: can't name node %s\n",
331 __FUNCTION__, name);
332 }
333}
334
335/*
336 * An Ethernet interface is being detached.
337 * Destroy its node.
338 */
339static void
340ng_ether_detach(struct ifnet *ifp)
341{
342 const node_p node = IFP2NG(ifp);
343 priv_p priv;
344
345 if (node == NULL) /* no node (why not?), ignore */
346 return;
347 ng_rmnode(node); /* break all links to other nodes */
348 node->flags |= NG_INVALID;
349 ng_unname(node); /* free name (and its reference) */
350 IFP2NG(ifp) = NULL; /* detach node from interface */
351 priv = node->private; /* free node private info */
352 bzero(priv, sizeof(*priv));
353 FREE(priv, M_NETGRAPH);
354 node->private = NULL;
355 ng_unref(node); /* free node itself */
356}
357
358/*
359 * Optimization for gluing the Ethernet header back onto
360 * the front of an incoming packet.
361 */
362static int
363ng_ether_glueback_header(struct mbuf **mp, struct ether_header *eh)
364{
365 struct mbuf *m = *mp;
366 uintfptr_t room;
367 int error = 0;
368
369 /*
370 * Possibly the header is already on the front.
371 * If this is the case so just move the markers back
372 * to re-include it. We lucked out.
373 * This allows us to avoid a yucky m_pullup
374 * in later nodes if it works.
375 */
376 if (eh == mtod(m, struct ether_header *) - 1) {
377 m->m_len += sizeof(*eh);
378 m->m_data -= sizeof(*eh);
379 m->m_pkthdr.len += sizeof(*eh);
380 goto done;
381 }
382
383 /*
384 * Alternatively there may be room even though
385 * it is stored somewhere else. If so, copy it in.
386 * This only safe because we KNOW that this packet has
387 * just been generated by an ethernet card, so there are
388 * no aliases to the buffer (not so for outgoing packets).
389 * Nearly all ethernet cards will end up producing mbufs
390 * that fall into these cases. So we are not optimizing
391 * contorted cases.
392 */
393 if ((m->m_flags & M_EXT) != 0) {
394 room = mtod(m, caddr_t) - m->m_ext.ext_buf;
395 if (room > m->m_ext.ext_size) /* garbage, fail immediately */
396 room = 0;
397 } else
398 room = mtod(m, caddr_t) - m->m_pktdat;
399
400 /*
401 * If we have room, just copy it and adjust
402 */
403 if (room >= sizeof(*eh)) {
404 m->m_len += sizeof(*eh);
405 m->m_data -= sizeof(*eh);
406 m->m_pkthdr.len += sizeof(*eh);
407 goto copy;
408 }
409
410 /*
411 * Doing anything more is likely to get more
412 * expensive than it's worth..
413 * it's probable that everything else is in one
414 * big lump. The next node will do an m_pullup()
415 * for exactly the amount of data it needs and
416 * hopefully everything after that will not
417 * need one. So let's just use M_PREPEND.
418 */
419 M_PREPEND(m, sizeof (*eh), M_DONTWAIT);
420 if (m == NULL) {
421 error = ENOBUFS;
422 goto done;
423 }
424
425copy:
426 /* Copy header and return (possibly new) mbuf */
427 bcopy((caddr_t)eh, mtod(m, struct ether_header *), sizeof(*eh));
428done:
429 *mp = m;
430 return error;
431}
432
433/******************************************************************
434 NETGRAPH NODE METHODS
435******************************************************************/
436
437/*
438 * It is not possible or allowable to create a node of this type.
439 * Nodes get created when the interface is attached (or, when
440 * this node type's KLD is loaded).
441 */
442static int
443ng_ether_constructor(node_p *nodep)
444{
445 return (EINVAL);
446}
447
448/*
449 * Check for attaching a new hook.
450 */
451static int
452ng_ether_newhook(node_p node, hook_p hook, const char *name)
453{
454 const priv_p priv = node->private;
455 u_char orphan = priv->lowerOrphan;
456 hook_p *hookptr;
457
458 /* Divert hook is an alias for lower */
459 if (strcmp(name, NG_ETHER_HOOK_DIVERT) == 0)
460 name = NG_ETHER_HOOK_LOWER;
461
462 /* Which hook? */
463 if (strcmp(name, NG_ETHER_HOOK_UPPER) == 0)
464 hookptr = &priv->upper;
465 else if (strcmp(name, NG_ETHER_HOOK_LOWER) == 0) {
466 hookptr = &priv->lower;
467 orphan = 0;
468 } else if (strcmp(name, NG_ETHER_HOOK_ORPHAN) == 0) {
469 hookptr = &priv->lower;
470 orphan = 1;
471 } else
472 return (EINVAL);
473
474 /* Check if already connected (shouldn't be, but doesn't hurt) */
475 if (*hookptr != NULL)
476 return (EISCONN);
477
478 /* OK */
479 *hookptr = hook;
480 priv->lowerOrphan = orphan;
481 return (0);
482}
483
484/*
485 * Receive an incoming control message.
486 */
487static int
488ng_ether_rcvmsg(node_p node, struct ng_mesg *msg, const char *retaddr,
489 struct ng_mesg **rptr, hook_p lasthook)
490{
491 const priv_p priv = node->private;
492 struct ng_mesg *resp = NULL;
493 int error = 0;
494
495 switch (msg->header.typecookie) {
496 case NGM_ETHER_COOKIE:
497 switch (msg->header.cmd) {
498 case NGM_ETHER_GET_IFNAME:
499 NG_MKRESPONSE(resp, msg, IFNAMSIZ + 1, M_NOWAIT);
500 if (resp == NULL) {
501 error = ENOMEM;
502 break;
503 }
504 snprintf(resp->data, IFNAMSIZ + 1,
505 "%s%d", priv->ifp->if_name, priv->ifp->if_unit);
506 break;
507 case NGM_ETHER_GET_IFINDEX:
508 NG_MKRESPONSE(resp, msg, sizeof(u_int32_t), M_NOWAIT);
509 if (resp == NULL) {
510 error = ENOMEM;
511 break;
512 }
513 *((u_int32_t *)resp->data) = priv->ifp->if_index;
514 break;
515 case NGM_ETHER_GET_ENADDR:
516 NG_MKRESPONSE(resp, msg, ETHER_ADDR_LEN, M_NOWAIT);
517 if (resp == NULL) {
518 error = ENOMEM;
519 break;
520 }
521 bcopy((IFP2AC(priv->ifp))->ac_enaddr,
522 resp->data, ETHER_ADDR_LEN);
523 break;
524 case NGM_ETHER_SET_ENADDR:
525 {
526 if (msg->header.arglen != ETHER_ADDR_LEN) {
527 error = EINVAL;
528 break;
529 }
530 error = if_setlladdr(priv->ifp,
531 (u_char *)msg->data, ETHER_ADDR_LEN);
532 break;
533 }
534 case NGM_ETHER_GET_PROMISC:
535 NG_MKRESPONSE(resp, msg, sizeof(u_int32_t), M_NOWAIT);
536 if (resp == NULL) {
537 error = ENOMEM;
538 break;
539 }
540 *((u_int32_t *)resp->data) = priv->promisc;
541 break;
542 case NGM_ETHER_SET_PROMISC:
543 {
544 u_char want;
545
546 if (msg->header.arglen != sizeof(u_int32_t)) {
547 error = EINVAL;
548 break;
549 }
550 want = !!*((u_int32_t *)msg->data);
551 if (want ^ priv->promisc) {
552 if ((error = ifpromisc(priv->ifp, want)) != 0)
553 break;
554 priv->promisc = want;
555 }
556 break;
557 }
558 case NGM_ETHER_GET_AUTOSRC:
559 NG_MKRESPONSE(resp, msg, sizeof(u_int32_t), M_NOWAIT);
560 if (resp == NULL) {
561 error = ENOMEM;
562 break;
563 }
564 *((u_int32_t *)resp->data) = priv->autoSrcAddr;
565 break;
566 case NGM_ETHER_SET_AUTOSRC:
567 if (msg->header.arglen != sizeof(u_int32_t)) {
568 error = EINVAL;
569 break;
570 }
571 priv->autoSrcAddr = !!*((u_int32_t *)msg->data);
572 break;
573 default:
574 error = EINVAL;
575 break;
576 }
577 break;
578 default:
579 error = EINVAL;
580 break;
581 }
582 if (rptr)
583 *rptr = resp;
584 else if (resp != NULL)
585 FREE(resp, M_NETGRAPH);
586 FREE(msg, M_NETGRAPH);
587 return (error);
588}
589
590/*
591 * Receive data on a hook.
592 */
593static int
594ng_ether_rcvdata(hook_p hook, struct mbuf *m, meta_p meta,
595 struct mbuf **ret_m, meta_p *ret_meta)
596{
597 const node_p node = hook->node;
598 const priv_p priv = node->private;
599
600 if (hook == priv->lower)
601 return ng_ether_rcv_lower(node, m, meta);
602 if (hook == priv->upper)
603 return ng_ether_rcv_upper(node, m, meta);
604 panic("%s: weird hook", __FUNCTION__);
605}
606
607/*
608 * Handle an mbuf received on the "lower" hook.
609 */
610static int
611ng_ether_rcv_lower(node_p node, struct mbuf *m, meta_p meta)
612{
613 const priv_p priv = node->private;
614
615 /* Make sure header is fully pulled up */
616 if (m->m_pkthdr.len < sizeof(struct ether_header)) {
617 NG_FREE_DATA(m, meta);
618 return (EINVAL);
619 }
620 if (m->m_len < sizeof(struct ether_header)
621 && (m = m_pullup(m, sizeof(struct ether_header))) == NULL) {
622 NG_FREE_META(meta);
623 return (ENOBUFS);
624 }
625
626 /* Drop in the MAC address if desired */
627 if (priv->autoSrcAddr) {
628 bcopy((IFP2AC(priv->ifp))->ac_enaddr,
629 mtod(m, struct ether_header *)->ether_shost,
630 ETHER_ADDR_LEN);
631 }
632
633 /* Send it on its way */
634 NG_FREE_META(meta);
635 return ether_output_frame(priv->ifp, m);
636}
637
638/*
639 * Handle an mbuf received on the "upper" hook.
640 */
641static int
642ng_ether_rcv_upper(node_p node, struct mbuf *m, meta_p meta)
643{
644 const priv_p priv = node->private;
645 struct ether_header *eh;
646
647 /* Check length and pull off header */
648 if (m->m_pkthdr.len < sizeof(*eh)) {
649 NG_FREE_DATA(m, meta);
650 return (EINVAL);
651 }
652 if (m->m_len < sizeof(*eh) && (m = m_pullup(m, sizeof(*eh))) == NULL) {
653 NG_FREE_META(meta);
654 return (ENOBUFS);
655 }
656 eh = mtod(m, struct ether_header *);
657 m->m_data += sizeof(*eh);
658 m->m_len -= sizeof(*eh);
659 m->m_pkthdr.len -= sizeof(*eh);
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