FreeBSD/Linux Kernel Cross Reference
sys/netgraph/ng_gif.c
1 /*
2 * ng_gif.c
3 */
4
5 /*-
6 * Copyright 2001 The Aerospace Corporation. All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 *
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions, and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions, and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
17 * 3. The name of The Aerospace Corporation may not be used to endorse or
18 * promote products derived from this software.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE AEROSPACE CORPORATION ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE AEROSPACE CORPORATION BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 *
32 *
33 * Copyright (c) 1996-2000 Whistle Communications, Inc.
34 * All rights reserved.
35 *
36 * Subject to the following obligations and disclaimer of warranty, use and
37 * redistribution of this software, in source or object code forms, with or
38 * without modifications are expressly permitted by Whistle Communications;
39 * provided, however, that:
40 * 1. Any and all reproductions of the source or object code must include the
41 * copyright notice above and the following disclaimer of warranties; and
42 * 2. No rights are granted, in any manner or form, to use Whistle
43 * Communications, Inc. trademarks, including the mark "WHISTLE
44 * COMMUNICATIONS" on advertising, endorsements, or otherwise except as
45 * such appears in the above copyright notice or in the software.
46 *
47 * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
48 * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
49 * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
50 * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
51 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
52 * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
53 * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
54 * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
55 * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
56 * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
57 * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
58 * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
59 * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
60 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
61 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
62 * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
63 * OF SUCH DAMAGE.
64 *
65 * $FreeBSD: src/sys/netgraph/ng_gif.c,v 1.23 2008/12/02 21:37:28 bz Exp $
66 */
67
68 /*
69 * ng_gif(4) netgraph node type
70 */
71
72 #include <sys/param.h>
73 #include <sys/systm.h>
74 #include <sys/kernel.h>
75 #include <sys/malloc.h>
76 #include <sys/mbuf.h>
77 #include <sys/errno.h>
78 #include <sys/syslog.h>
79 #include <sys/socket.h>
80 #include <sys/vimage.h>
81
82 #include <net/if.h>
83 #include <net/route.h>
84 #include <net/if_types.h>
85 #include <net/if_var.h>
86 #include <net/if_gif.h>
87 #include <net/vnet.h>
88
89 #include <netgraph/ng_message.h>
90 #include <netgraph/netgraph.h>
91 #include <netgraph/ng_parse.h>
92 #include <netgraph/ng_gif.h>
93
94 #define IFP2NG(ifp) ((struct ng_node *)((struct gif_softc *)(ifp->if_softc))->gif_netgraph)
95 #define IFP2NG_SET(ifp, val) (((struct gif_softc *)(ifp->if_softc))->gif_netgraph = (val))
96
97 /* Per-node private data */
98 struct private {
99 struct ifnet *ifp; /* associated interface */
100 hook_p lower; /* lower OR orphan hook connection */
101 u_char lowerOrphan; /* whether lower is lower or orphan */
102 };
103 typedef struct private *priv_p;
104
105 /* Functional hooks called from if_gif.c */
106 static void ng_gif_input(struct ifnet *ifp, struct mbuf **mp, int af);
107 static void ng_gif_input_orphan(struct ifnet *ifp, struct mbuf *m, int af);
108 static void ng_gif_attach(struct ifnet *ifp);
109 static void ng_gif_detach(struct ifnet *ifp);
110
111 /* Other functions */
112 static void ng_gif_input2(node_p node, struct mbuf **mp, int af);
113 static int ng_gif_glue_af(struct mbuf **mp, int af);
114 static int ng_gif_rcv_lower(node_p node, struct mbuf *m);
115
116 /* Netgraph node methods */
117 static ng_constructor_t ng_gif_constructor;
118 static ng_rcvmsg_t ng_gif_rcvmsg;
119 static ng_shutdown_t ng_gif_shutdown;
120 static ng_newhook_t ng_gif_newhook;
121 static ng_connect_t ng_gif_connect;
122 static ng_rcvdata_t ng_gif_rcvdata;
123 static ng_disconnect_t ng_gif_disconnect;
124 static int ng_gif_mod_event(module_t mod, int event, void *data);
125
126 /* List of commands and how to convert arguments to/from ASCII */
127 static const struct ng_cmdlist ng_gif_cmdlist[] = {
128 {
129 NGM_GIF_COOKIE,
130 NGM_GIF_GET_IFNAME,
131 "getifname",
132 NULL,
133 &ng_parse_string_type
134 },
135 {
136 NGM_GIF_COOKIE,
137 NGM_GIF_GET_IFINDEX,
138 "getifindex",
139 NULL,
140 &ng_parse_int32_type
141 },
142 { 0 }
143 };
144
145 static struct ng_type ng_gif_typestruct = {
146 .version = NG_ABI_VERSION,
147 .name = NG_GIF_NODE_TYPE,
148 .mod_event = ng_gif_mod_event,
149 .constructor = ng_gif_constructor,
150 .rcvmsg = ng_gif_rcvmsg,
151 .shutdown = ng_gif_shutdown,
152 .newhook = ng_gif_newhook,
153 .connect = ng_gif_connect,
154 .rcvdata = ng_gif_rcvdata,
155 .disconnect = ng_gif_disconnect,
156 .cmdlist = ng_gif_cmdlist,
157 };
158 MODULE_DEPEND(ng_gif, if_gif, 1,1,1);
159 NETGRAPH_INIT(gif, &ng_gif_typestruct);
160
161 /******************************************************************
162 GIF FUNCTION HOOKS
163 ******************************************************************/
164
165 /*
166 * Handle a packet that has come in on an interface. We get to
167 * look at it here before any upper layer protocols do.
168 *
169 * NOTE: this function will get called at splimp()
170 */
171 static void
172 ng_gif_input(struct ifnet *ifp, struct mbuf **mp, int af)
173 {
174 const node_p node = IFP2NG(ifp);
175 const priv_p priv = NG_NODE_PRIVATE(node);
176
177 /* If "lower" hook not connected, let packet continue */
178 if (priv->lower == NULL || priv->lowerOrphan)
179 return;
180 ng_gif_input2(node, mp, af);
181 }
182
183 /*
184 * Handle a packet that has come in on an interface, and which
185 * does not match any of our known protocols (an ``orphan'').
186 *
187 * NOTE: this function will get called at splimp()
188 */
189 static void
190 ng_gif_input_orphan(struct ifnet *ifp, struct mbuf *m, int af)
191 {
192 const node_p node = IFP2NG(ifp);
193 const priv_p priv = NG_NODE_PRIVATE(node);
194
195 /* If "orphan" hook not connected, let packet continue */
196 if (priv->lower == NULL || !priv->lowerOrphan) {
197 m_freem(m);
198 return;
199 }
200 ng_gif_input2(node, &m, af);
201 if (m != NULL)
202 m_freem(m);
203 }
204
205 /*
206 * Handle a packet that has come in on a gif interface.
207 * Attach the address family to the mbuf for later use.
208 *
209 * NOTE: this function will get called at splimp()
210 */
211 static void
212 ng_gif_input2(node_p node, struct mbuf **mp, int af)
213 {
214 const priv_p priv = NG_NODE_PRIVATE(node);
215 int error;
216
217 /* Glue address family on */
218 if ((error = ng_gif_glue_af(mp, af)) != 0)
219 return;
220
221 /* Send out lower/orphan hook */
222 NG_SEND_DATA_ONLY(error, priv->lower, *mp);
223 *mp = NULL;
224 }
225
226 /*
227 * A new gif interface has been attached.
228 * Create a new node for it, etc.
229 */
230 static void
231 ng_gif_attach(struct ifnet *ifp)
232 {
233 priv_p priv;
234 node_p node;
235
236 /* Create node */
237 KASSERT(!IFP2NG(ifp), ("%s: node already exists?", __func__));
238 if (ng_make_node_common(&ng_gif_typestruct, &node) != 0) {
239 log(LOG_ERR, "%s: can't %s for %s\n",
240 __func__, "create node", ifp->if_xname);
241 return;
242 }
243
244 /* Allocate private data */
245 priv = malloc(sizeof(*priv), M_NETGRAPH, M_NOWAIT | M_ZERO);
246 if (priv == NULL) {
247 log(LOG_ERR, "%s: can't %s for %s\n",
248 __func__, "allocate memory", ifp->if_xname);
249 NG_NODE_UNREF(node);
250 return;
251 }
252 NG_NODE_SET_PRIVATE(node, priv);
253 priv->ifp = ifp;
254 IFP2NG_SET(ifp, node);
255
256 /* Try to give the node the same name as the interface */
257 if (ng_name_node(node, ifp->if_xname) != 0) {
258 log(LOG_WARNING, "%s: can't name node %s\n",
259 __func__, ifp->if_xname);
260 }
261 }
262
263 /*
264 * An interface is being detached.
265 * REALLY Destroy its node.
266 */
267 static void
268 ng_gif_detach(struct ifnet *ifp)
269 {
270 const node_p node = IFP2NG(ifp);
271 priv_p priv;
272
273 if (node == NULL) /* no node (why not?), ignore */
274 return;
275 priv = NG_NODE_PRIVATE(node);
276 NG_NODE_REALLY_DIE(node); /* Force real removal of node */
277 /*
278 * We can't assume the ifnet is still around when we run shutdown
279 * So zap it now. XXX We HOPE that anything running at this time
280 * handles it (as it should in the non netgraph case).
281 */
282 IFP2NG_SET(ifp, NULL);
283 priv->ifp = NULL; /* XXX race if interrupted an output packet */
284 ng_rmnode_self(node); /* remove all netgraph parts */
285 }
286
287 /*
288 * Optimization for gluing the address family onto
289 * the front of an incoming packet.
290 */
291 static int
292 ng_gif_glue_af(struct mbuf **mp, int af)
293 {
294 struct mbuf *m = *mp;
295 int error = 0;
296 sa_family_t tmp_af;
297
298 tmp_af = (sa_family_t) af;
299
300 /*
301 * XXX: should try to bring back some of the optimizations from
302 * ng_ether.c
303 */
304
305 /*
306 * Doing anything more is likely to get more
307 * expensive than it's worth..
308 * it's probable that everything else is in one
309 * big lump. The next node will do an m_pullup()
310 * for exactly the amount of data it needs and
311 * hopefully everything after that will not
312 * need one. So let's just use M_PREPEND.
313 */
314 M_PREPEND(m, sizeof (tmp_af), M_DONTWAIT);
315 if (m == NULL) {
316 error = ENOBUFS;
317 goto done;
318 }
319
320 #if 0
321 copy:
322 #endif
323 /* Copy header and return (possibly new) mbuf */
324 *mtod(m, sa_family_t *) = tmp_af;
325 #if 0
326 bcopy((caddr_t)&tmp_af, mtod(m, sa_family_t *), sizeof(tmp_af));
327 #endif
328 done:
329 *mp = m;
330 return error;
331 }
332
333 /******************************************************************
334 NETGRAPH NODE METHODS
335 ******************************************************************/
336
337 /*
338 * It is not possible or allowable to create a node of this type.
339 * Nodes get created when the interface is attached (or, when
340 * this node type's KLD is loaded).
341 */
342 static int
343 ng_gif_constructor(node_p node)
344 {
345 return (EINVAL);
346 }
347
348 /*
349 * Check for attaching a new hook.
350 */
351 static int
352 ng_gif_newhook(node_p node, hook_p hook, const char *name)
353 {
354 const priv_p priv = NG_NODE_PRIVATE(node);
355 u_char orphan = priv->lowerOrphan;
356 hook_p *hookptr;
357
358 /* Divert hook is an alias for lower */
359 if (strcmp(name, NG_GIF_HOOK_DIVERT) == 0)
360 name = NG_GIF_HOOK_LOWER;
361
362 /* Which hook? */
363 if (strcmp(name, NG_GIF_HOOK_LOWER) == 0) {
364 hookptr = &priv->lower;
365 orphan = 0;
366 } else if (strcmp(name, NG_GIF_HOOK_ORPHAN) == 0) {
367 hookptr = &priv->lower;
368 orphan = 1;
369 } else
370 return (EINVAL);
371
372 /* Check if already connected (shouldn't be, but doesn't hurt) */
373 if (*hookptr != NULL)
374 return (EISCONN);
375
376 /* OK */
377 *hookptr = hook;
378 priv->lowerOrphan = orphan;
379 return (0);
380 }
381
382 /*
383 * Hooks are attached, adjust to force queueing.
384 * We don't really care which hook it is.
385 * they should all be queuing for outgoing data.
386 */
387 static int
388 ng_gif_connect(hook_p hook)
389 {
390 NG_HOOK_FORCE_QUEUE(NG_HOOK_PEER(hook));
391 return (0);
392 }
393
394 /*
395 * Receive an incoming control message.
396 */
397 static int
398 ng_gif_rcvmsg(node_p node, item_p item, hook_p lasthook)
399 {
400 const priv_p priv = NG_NODE_PRIVATE(node);
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_GIF_COOKIE:
408 switch (msg->header.cmd) {
409 case NGM_GIF_GET_IFNAME:
410 NG_MKRESPONSE(resp, msg, IFNAMSIZ, M_NOWAIT);
411 if (resp == NULL) {
412 error = ENOMEM;
413 break;
414 }
415 strlcpy(resp->data, priv->ifp->if_xname, IFNAMSIZ);
416 break;
417 case NGM_GIF_GET_IFINDEX:
418 NG_MKRESPONSE(resp, msg, sizeof(u_int32_t), M_NOWAIT);
419 if (resp == NULL) {
420 error = ENOMEM;
421 break;
422 }
423 *((u_int32_t *)resp->data) = priv->ifp->if_index;
424 break;
425 default:
426 error = EINVAL;
427 break;
428 }
429 break;
430 default:
431 error = EINVAL;
432 break;
433 }
434 NG_RESPOND_MSG(error, node, item, resp);
435 NG_FREE_MSG(msg);
436 return (error);
437 }
438
439 /*
440 * Receive data on a hook.
441 */
442 static int
443 ng_gif_rcvdata(hook_p hook, item_p item)
444 {
445 const node_p node = NG_HOOK_NODE(hook);
446 const priv_p priv = NG_NODE_PRIVATE(node);
447 struct mbuf *m;
448
449 NGI_GET_M(item, m);
450 NG_FREE_ITEM(item);
451
452 if (hook == priv->lower)
453 return ng_gif_rcv_lower(node, m);
454 panic("%s: weird hook", __func__);
455 }
456
457 /*
458 * Handle an mbuf received on the "lower" hook.
459 */
460 static int
461 ng_gif_rcv_lower(node_p node, struct mbuf *m)
462 {
463 struct sockaddr dst;
464 const priv_p priv = NG_NODE_PRIVATE(node);
465
466 bzero(&dst, sizeof(dst));
467
468 /* Make sure header is fully pulled up */
469 if (m->m_pkthdr.len < sizeof(sa_family_t)) {
470 NG_FREE_M(m);
471 return (EINVAL);
472 }
473 if (m->m_len < sizeof(sa_family_t)
474 && (m = m_pullup(m, sizeof(sa_family_t))) == NULL) {
475 return (ENOBUFS);
476 }
477
478 dst.sa_family = *mtod(m, sa_family_t *);
479 m_adj(m, sizeof(sa_family_t));
480
481 /* Send it on its way */
482 /*
483 * XXX: gif_output only uses dst for the family and passes the
484 * fourth argument (rt) to in{,6}_gif_output which ignore it.
485 * If this changes ng_gif will probably break.
486 */
487 return gif_output(priv->ifp, m, &dst, NULL);
488 }
489
490 /*
491 * Shutdown node. This resets the node but does not remove it
492 * unless the REALLY_DIE flag is set.
493 */
494 static int
495 ng_gif_shutdown(node_p node)
496 {
497 const priv_p priv = NG_NODE_PRIVATE(node);
498
499 if (node->nd_flags & NGF_REALLY_DIE) {
500 /*
501 * WE came here because the gif interface is being destroyed,
502 * so stop being persistant.
503 * Actually undo all the things we did on creation.
504 * Assume the ifp has already been freed.
505 */
506 NG_NODE_SET_PRIVATE(node, NULL);
507 free(priv, M_NETGRAPH);
508 NG_NODE_UNREF(node); /* free node itself */
509 return (0);
510 }
511 NG_NODE_REVIVE(node); /* Signal ng_rmnode we are persisant */
512 return (0);
513 }
514
515 /*
516 * Hook disconnection.
517 */
518 static int
519 ng_gif_disconnect(hook_p hook)
520 {
521 const priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
522
523 if (hook == priv->lower) {
524 priv->lower = NULL;
525 priv->lowerOrphan = 0;
526 } else
527 panic("%s: weird hook", __func__);
528 if ((NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0)
529 && (NG_NODE_IS_VALID(NG_HOOK_NODE(hook))))
530 ng_rmnode_self(NG_HOOK_NODE(hook)); /* reset node */
531
532 return (0);
533 }
534
535 /******************************************************************
536 INITIALIZATION
537 ******************************************************************/
538
539 /*
540 * Handle loading and unloading for this node type.
541 */
542 static int
543 ng_gif_mod_event(module_t mod, int event, void *data)
544 {
545 VNET_ITERATOR_DECL(vnet_iter);
546 struct ifnet *ifp;
547 int error = 0;
548 int s;
549
550 s = splnet();
551 switch (event) {
552 case MOD_LOAD:
553
554 /* Register function hooks */
555 if (ng_gif_attach_p != NULL) {
556 error = EEXIST;
557 break;
558 }
559 ng_gif_attach_p = ng_gif_attach;
560 ng_gif_detach_p = ng_gif_detach;
561 ng_gif_input_p = ng_gif_input;
562 ng_gif_input_orphan_p = ng_gif_input_orphan;
563
564 /* Create nodes for any already-existing gif interfaces */
565 IFNET_RLOCK();
566 VNET_LIST_RLOCK();
567 VNET_FOREACH(vnet_iter) {
568 CURVNET_SET_QUIET(vnet_iter); /* XXX revisit quiet */
569 INIT_VNET_NET(curvnet);
570 TAILQ_FOREACH(ifp, &V_ifnet, if_link) {
571 if (ifp->if_type == IFT_GIF)
572 ng_gif_attach(ifp);
573 }
574 CURVNET_RESTORE();
575 }
576 VNET_LIST_RUNLOCK();
577 IFNET_RUNLOCK();
578 break;
579
580 case MOD_UNLOAD:
581
582 /*
583 * Note that the base code won't try to unload us until
584 * all nodes have been removed, and that can't happen
585 * until all gif interfaces are destroyed. In any
586 * case, we know there are no nodes left if the action
587 * is MOD_UNLOAD, so there's no need to detach any nodes.
588 *
589 * XXX: what about manual unloads?!?
590 */
591
592 /* Unregister function hooks */
593 ng_gif_attach_p = NULL;
594 ng_gif_detach_p = NULL;
595 ng_gif_input_p = NULL;
596 ng_gif_input_orphan_p = NULL;
597 break;
598
599 default:
600 error = EOPNOTSUPP;
601 break;
602 }
603 splx(s);
604 return (error);
605 }
606
607
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