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 *
|
67#define IFP2NG(ifp) ((struct ng_node *)((struct arpcom *)(ifp))->ac_netgraph)
68
69/* Per-node private data */
70struct private {
71 struct ifnet *ifp; /* associated interface */
72 hook_p upper; /* upper hook connection */
73 hook_p lower; /* lower OR orphan hook connection */
74 u_char lowerOrphan; /* whether lower is lower or orphan */
75};
76typedef struct private *priv_p;
77
78/* Functional hooks called from if_ethersubr.c */
79static void ng_ether_input(struct ifnet *ifp,
80 struct mbuf **mp, struct ether_header *eh);
81static void ng_ether_input_orphan(struct ifnet *ifp,
82 struct mbuf *m, struct ether_header *eh);
83static int ng_ether_output(struct ifnet *ifp, struct mbuf **mp);
84static void ng_ether_attach(struct ifnet *ifp);
85static void ng_ether_detach(struct ifnet *ifp);
86
87/* Other functions */
88static void ng_ether_input2(node_p node,
89 struct mbuf **mp, struct ether_header *eh);
90static int ng_ether_glueback_header(struct mbuf **mp,
91 struct ether_header *eh);
92static int ng_ether_rcv_lower(node_p node, struct mbuf *m, meta_p meta);
93static int ng_ether_rcv_upper(node_p node, struct mbuf *m, meta_p meta);
94
95/* Netgraph node methods */
96static ng_constructor_t ng_ether_constructor;
97static ng_rcvmsg_t ng_ether_rcvmsg;
98static ng_shutdown_t ng_ether_rmnode;
99static ng_newhook_t ng_ether_newhook;
100static ng_rcvdata_t ng_ether_rcvdata;
101static ng_disconnect_t ng_ether_disconnect;
102static int ng_ether_mod_event(module_t mod, int event, void *data);
103
104/* List of commands and how to convert arguments to/from ASCII */
105static const struct ng_cmdlist ng_ether_cmdlist[] = {
106 {
107 NGM_ETHER_COOKIE,
108 NGM_ETHER_GET_IFNAME,
109 "getifname",
110 NULL,
111 &ng_parse_string_type
112 },
113 {
114 NGM_ETHER_COOKIE,
115 NGM_ETHER_GET_IFINDEX,
116 "getifindex",
117 NULL,
118 &ng_parse_int32_type
119 },
120 { 0 }
121};
122
123static struct ng_type ng_ether_typestruct = {
124 NG_VERSION,
125 NG_ETHER_NODE_TYPE,
126 ng_ether_mod_event,
127 ng_ether_constructor,
128 ng_ether_rcvmsg,
129 ng_ether_rmnode,
130 ng_ether_newhook,
131 NULL,
132 NULL,
133 ng_ether_rcvdata,
134 ng_ether_rcvdata,
135 ng_ether_disconnect,
136 ng_ether_cmdlist,
137};
138NETGRAPH_INIT(ether, &ng_ether_typestruct);
139
140/******************************************************************
141 ETHERNET FUNCTION HOOKS
142******************************************************************/
143
144/*
145 * Handle a packet that has come in on an interface. We get to
146 * look at it here before any upper layer protocols do.
147 *
148 * NOTE: this function will get called at splimp()
149 */
150static void
151ng_ether_input(struct ifnet *ifp,
152 struct mbuf **mp, struct ether_header *eh)
153{
154 const node_p node = IFP2NG(ifp);
155 const priv_p priv = node->private;
156
157 /* If "lower" hook not connected, let packet continue */
158 if (priv->lower == NULL || priv->lowerOrphan)
159 return;
160 ng_ether_input2(node, mp, eh);
161}
162
163/*
164 * Handle a packet that has come in on an interface, and which
165 * does not match any of our known protocols (an ``orphan'').
166 *
167 * NOTE: this function will get called at splimp()
168 */
169static void
170ng_ether_input_orphan(struct ifnet *ifp,
171 struct mbuf *m, struct ether_header *eh)
172{
173 const node_p node = IFP2NG(ifp);
174 const priv_p priv = node->private;
175
176 /* If "orphan" hook not connected, let packet continue */
177 if (priv->lower == NULL || !priv->lowerOrphan) {
178 m_freem(m);
179 return;
180 }
181 ng_ether_input2(node, &m, eh);
182 if (m != NULL)
183 m_freem(m);
184}
185
186/*
187 * Handle a packet that has come in on an interface.
188 * The Ethernet header has already been detached from the mbuf,
189 * so we have to put it back.
190 *
191 * NOTE: this function will get called at splimp()
192 */
193static void
194ng_ether_input2(node_p node, struct mbuf **mp, struct ether_header *eh)
195{
196 const priv_p priv = node->private;
197 meta_p meta = NULL;
198 int error;
199
200 /* Glue Ethernet header back on */
201 if ((error = ng_ether_glueback_header(mp, eh)) != 0)
202 return;
203
204 /* Send out lower/orphan hook */
205 NG_SEND_DATAQ(error, priv->lower, *mp, meta);
206
207 /* Any reflected packet must come later due to queuing */
208 *mp = NULL;
209}
210
211/*
212 * Handle a packet that is going out on an interface.
213 * The Ethernet header is already attached to the mbuf.
214 */
215static int
216ng_ether_output(struct ifnet *ifp, struct mbuf **mp)
217{
218 const node_p node = IFP2NG(ifp);
219 const priv_p priv = node->private;
220 meta_p meta = NULL;
221 int error = 0;
222
223 /* If "upper" hook not connected, let packet continue */
224 if (priv->upper == NULL)
225 return (0);
226
227 /* Send it out "upper" hook */
228 NG_SEND_DATA_RET(error, priv->upper, *mp, meta);
229
230 /* If we got a reflected packet back, handle it */
231 if (error == 0 && *mp != NULL) {
232 error = ng_ether_rcv_upper(node, *mp, meta);
233 *mp = NULL;
234 }
235 return (error);
236}
237
238/*
239 * A new Ethernet interface has been attached.
240 * Create a new node for it, etc.
241 */
242static void
243ng_ether_attach(struct ifnet *ifp)
244{
245 char name[IFNAMSIZ + 1];
246 priv_p priv;
247 node_p node;
248
249 /* Create node */
250 KASSERT(!IFP2NG(ifp), ("%s: node already exists?", __FUNCTION__));
251 snprintf(name, sizeof(name), "%s%d", ifp->if_name, ifp->if_unit);
252 if (ng_make_node_common(&ng_ether_typestruct, &node) != 0) {
253 log(LOG_ERR, "%s: can't %s for %s\n",
254 __FUNCTION__, "create node", name);
255 return;
256 }
257
258 /* Allocate private data */
259 MALLOC(priv, priv_p, sizeof(*priv), M_NETGRAPH, M_NOWAIT);
260 if (priv == NULL) {
261 log(LOG_ERR, "%s: can't %s for %s\n",
262 __FUNCTION__, "allocate memory", name);
263 ng_unref(node);
264 return;
265 }
266 bzero(priv, sizeof(*priv));
267 node->private = priv;
268 priv->ifp = ifp;
269 IFP2NG(ifp) = node;
270
271 /* Try to give the node the same name as the interface */
272 if (ng_name_node(node, name) != 0) {
273 log(LOG_WARNING, "%s: can't name node %s\n",
274 __FUNCTION__, name);
275 }
276}
277
278/*
279 * An Ethernet interface is being detached.
280 * Destroy its node.
281 */
282static void
283ng_ether_detach(struct ifnet *ifp)
284{
285 const node_p node = IFP2NG(ifp);
286 priv_p priv;
287
288 if (node == NULL) /* no node (why not?), ignore */
289 return;
290 ng_rmnode(node); /* break all links to other nodes */
291 IFP2NG(ifp) = NULL; /* detach node from interface */
292 priv = node->private; /* free node private info */
293 bzero(priv, sizeof(*priv));
294 FREE(priv, M_NETGRAPH);
295 node->private = NULL;
296 ng_unref(node); /* free node itself */
297}
298
299/*
300 * Optimization for gluing the Ethernet header back onto
301 * the front of an incoming packet.
302 */
303static int
304ng_ether_glueback_header(struct mbuf **mp, struct ether_header *eh)
305{
306 struct mbuf *m = *mp;
307 uintfptr_t room;
308 int error = 0;
309
310 /*
311 * Possibly the header is already on the front.
312 * If this is the case so just move the markers back
313 * to re-include it. We lucked out.
314 * This allows us to avoid a yucky m_pullup
315 * in later nodes if it works.
316 */
317 if (eh == mtod(m, struct ether_header *) - 1) {
318 m->m_len += sizeof(*eh);
319 m->m_data -= sizeof(*eh);
320 m->m_pkthdr.len += sizeof(*eh);
321 goto done;
322 }
323
324 /*
325 * Alternatively there may be room even though
326 * it is stored somewhere else. If so, copy it in.
327 * This only safe because we KNOW that this packet has
328 * just been generated by an ethernet card, so there are
329 * no aliases to the buffer (not so for outgoing packets).
330 * Nearly all ethernet cards will end up producing mbufs
331 * that fall into these cases. So we are not optimizing
332 * contorted cases.
333 */
334 if ((m->m_flags & M_EXT) != 0) {
335 room = mtod(m, caddr_t) - m->m_ext.ext_buf;
336 if (room > m->m_ext.ext_size) /* garbage, fail immediately */
337 room = 0;
338 } else
339 room = mtod(m, caddr_t) - m->m_pktdat;
340
341 /*
342 * If we have room, just copy it and adjust
343 */
344 if (room >= sizeof(*eh)) {
345 m->m_len += sizeof(*eh);
346 m->m_data -= sizeof(*eh);
347 m->m_pkthdr.len += sizeof(*eh);
348 goto copy;
349 }
350
351 /*
352 * Doing anything more is likely to get more
353 * expensive than it's worth..
354 * it's probable that everything else is in one
355 * big lump. The next node will do an m_pullup()
356 * for exactly the amount of data it needs and
357 * hopefully everything after that will not
358 * need one. So let's just use M_PREPEND.
359 */
360 M_PREPEND(m, sizeof (*eh), M_DONTWAIT);
361 if (m == NULL) {
362 error = ENOBUFS;
363 goto done;
364 }
365
366copy:
367 /* Copy header and return (possibly new) mbuf */
368 bcopy((caddr_t)eh, mtod(m, struct ether_header *), sizeof(*eh));
369done:
370 *mp = m;
371 return error;
372}
373
374/******************************************************************
375 NETGRAPH NODE METHODS
376******************************************************************/
377
378/*
379 * It is not possible or allowable to create a node of this type.
380 * Nodes get created when the interface is attached (or, when
381 * this node type's KLD is loaded).
382 */
383static int
384ng_ether_constructor(node_p *nodep)
385{
386 return (EINVAL);
387}
388
389/*
390 * Check for attaching a new hook.
391 */
392static int
393ng_ether_newhook(node_p node, hook_p hook, const char *name)
394{
395 const priv_p priv = node->private;
396 u_char orphan = priv->lowerOrphan;
397 hook_p *hookptr;
398
399 /* Divert hook is an alias for lower */
400 if (strcmp(name, NG_ETHER_HOOK_DIVERT) == 0)
401 name = NG_ETHER_HOOK_LOWER;
402
403 /* Which hook? */
404 if (strcmp(name, NG_ETHER_HOOK_UPPER) == 0)
405 hookptr = &priv->upper;
406 else if (strcmp(name, NG_ETHER_HOOK_LOWER) == 0) {
407 hookptr = &priv->lower;
408 orphan = 0;
409 } else if (strcmp(name, NG_ETHER_HOOK_ORPHAN) == 0) {
410 hookptr = &priv->lower;
411 orphan = 1;
412 } else
413 return (EINVAL);
414
415 /* Check if already connected (shouldn't be, but doesn't hurt) */
416 if (*hookptr != NULL)
417 return (EISCONN);
418
419 /* OK */
420 *hookptr = hook;
421 priv->lowerOrphan = orphan;
422 return (0);
423}
424
425/*
426 * Receive an incoming control message.
427 */
428static int
429ng_ether_rcvmsg(node_p node, struct ng_mesg *msg, const char *retaddr,
430 struct ng_mesg **rptr, hook_p lasthook)
431{
432 const priv_p priv = node->private;
433 struct ng_mesg *resp = NULL;
434 int error = 0;
435
436 switch (msg->header.typecookie) {
437 case NGM_ETHER_COOKIE:
438 switch (msg->header.cmd) {
439 case NGM_ETHER_GET_IFNAME:
440 NG_MKRESPONSE(resp, msg, IFNAMSIZ + 1, M_NOWAIT);
441 if (resp == NULL) {
442 error = ENOMEM;
443 break;
444 }
445 snprintf(resp->data, IFNAMSIZ + 1,
446 "%s%d", priv->ifp->if_name, priv->ifp->if_unit);
447 break;
448 case NGM_ETHER_GET_IFINDEX:
449 NG_MKRESPONSE(resp, msg, sizeof(u_int32_t), M_NOWAIT);
450 if (resp == NULL) {
451 error = ENOMEM;
452 break;
453 }
454 *((u_int32_t *)resp->data) = priv->ifp->if_index;
455 break;
456 default:
457 error = EINVAL;
458 break;
459 }
460 break;
461 default:
462 error = EINVAL;
463 break;
464 }
465 if (rptr)
466 *rptr = resp;
467 else if (resp != NULL)
468 FREE(resp, M_NETGRAPH);
469 FREE(msg, M_NETGRAPH);
470 return (error);
471}
472
473/*
474 * Receive data on a hook.
475 */
476static int
477ng_ether_rcvdata(hook_p hook, struct mbuf *m, meta_p meta,
478 struct mbuf **ret_m, meta_p *ret_meta)
479{
480 const node_p node = hook->node;
481 const priv_p priv = node->private;
482
483 if (hook == priv->lower)
484 return ng_ether_rcv_lower(node, m, meta);
485 if (hook == priv->upper)
486 return ng_ether_rcv_upper(node, m, meta);
487 panic("%s: weird hook", __FUNCTION__);
488}
489
490/*
491 * Handle an mbuf received on the "lower" hook.
492 */
493static int
494ng_ether_rcv_lower(node_p node, struct mbuf *m, meta_p meta)
495{
496 const priv_p priv = node->private;
| 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};
77typedef struct private *priv_p;
78
79/* Functional hooks called from if_ethersubr.c */
80static void ng_ether_input(struct ifnet *ifp,
81 struct mbuf **mp, struct ether_header *eh);
82static void ng_ether_input_orphan(struct ifnet *ifp,
83 struct mbuf *m, struct ether_header *eh);
84static int ng_ether_output(struct ifnet *ifp, struct mbuf **mp);
85static void ng_ether_attach(struct ifnet *ifp);
86static void ng_ether_detach(struct ifnet *ifp);
87
88/* Other functions */
89static void ng_ether_input2(node_p node,
90 struct mbuf **mp, struct ether_header *eh);
91static int ng_ether_glueback_header(struct mbuf **mp,
92 struct ether_header *eh);
93static int ng_ether_rcv_lower(node_p node, struct mbuf *m, meta_p meta);
94static int ng_ether_rcv_upper(node_p node, struct mbuf *m, meta_p meta);
95
96/* Netgraph node methods */
97static ng_constructor_t ng_ether_constructor;
98static ng_rcvmsg_t ng_ether_rcvmsg;
99static ng_shutdown_t ng_ether_rmnode;
100static ng_newhook_t ng_ether_newhook;
101static ng_rcvdata_t ng_ether_rcvdata;
102static ng_disconnect_t ng_ether_disconnect;
103static int ng_ether_mod_event(module_t mod, int event, void *data);
104
105/* List of commands and how to convert arguments to/from ASCII */
106static const struct ng_cmdlist ng_ether_cmdlist[] = {
107 {
108 NGM_ETHER_COOKIE,
109 NGM_ETHER_GET_IFNAME,
110 "getifname",
111 NULL,
112 &ng_parse_string_type
113 },
114 {
115 NGM_ETHER_COOKIE,
116 NGM_ETHER_GET_IFINDEX,
117 "getifindex",
118 NULL,
119 &ng_parse_int32_type
120 },
121 { 0 }
122};
123
124static struct ng_type ng_ether_typestruct = {
125 NG_VERSION,
126 NG_ETHER_NODE_TYPE,
127 ng_ether_mod_event,
128 ng_ether_constructor,
129 ng_ether_rcvmsg,
130 ng_ether_rmnode,
131 ng_ether_newhook,
132 NULL,
133 NULL,
134 ng_ether_rcvdata,
135 ng_ether_rcvdata,
136 ng_ether_disconnect,
137 ng_ether_cmdlist,
138};
139NETGRAPH_INIT(ether, &ng_ether_typestruct);
140
141/******************************************************************
142 ETHERNET FUNCTION HOOKS
143******************************************************************/
144
145/*
146 * Handle a packet that has come in on an interface. We get to
147 * look at it here before any upper layer protocols do.
148 *
149 * NOTE: this function will get called at splimp()
150 */
151static void
152ng_ether_input(struct ifnet *ifp,
153 struct mbuf **mp, struct ether_header *eh)
154{
155 const node_p node = IFP2NG(ifp);
156 const priv_p priv = node->private;
157
158 /* If "lower" hook not connected, let packet continue */
159 if (priv->lower == NULL || priv->lowerOrphan)
160 return;
161 ng_ether_input2(node, mp, eh);
162}
163
164/*
165 * Handle a packet that has come in on an interface, and which
166 * does not match any of our known protocols (an ``orphan'').
167 *
168 * NOTE: this function will get called at splimp()
169 */
170static void
171ng_ether_input_orphan(struct ifnet *ifp,
172 struct mbuf *m, struct ether_header *eh)
173{
174 const node_p node = IFP2NG(ifp);
175 const priv_p priv = node->private;
176
177 /* If "orphan" hook not connected, let packet continue */
178 if (priv->lower == NULL || !priv->lowerOrphan) {
179 m_freem(m);
180 return;
181 }
182 ng_ether_input2(node, &m, eh);
183 if (m != NULL)
184 m_freem(m);
185}
186
187/*
188 * Handle a packet that has come in on an interface.
189 * The Ethernet header has already been detached from the mbuf,
190 * so we have to put it back.
191 *
192 * NOTE: this function will get called at splimp()
193 */
194static void
195ng_ether_input2(node_p node, struct mbuf **mp, struct ether_header *eh)
196{
197 const priv_p priv = node->private;
198 meta_p meta = NULL;
199 int error;
200
201 /* Glue Ethernet header back on */
202 if ((error = ng_ether_glueback_header(mp, eh)) != 0)
203 return;
204
205 /* Send out lower/orphan hook */
206 NG_SEND_DATAQ(error, priv->lower, *mp, meta);
207
208 /* Any reflected packet must come later due to queuing */
209 *mp = NULL;
210}
211
212/*
213 * Handle a packet that is going out on an interface.
214 * The Ethernet header is already attached to the mbuf.
215 */
216static int
217ng_ether_output(struct ifnet *ifp, struct mbuf **mp)
218{
219 const node_p node = IFP2NG(ifp);
220 const priv_p priv = node->private;
221 meta_p meta = NULL;
222 int error = 0;
223
224 /* If "upper" hook not connected, let packet continue */
225 if (priv->upper == NULL)
226 return (0);
227
228 /* Send it out "upper" hook */
229 NG_SEND_DATA_RET(error, priv->upper, *mp, meta);
230
231 /* If we got a reflected packet back, handle it */
232 if (error == 0 && *mp != NULL) {
233 error = ng_ether_rcv_upper(node, *mp, meta);
234 *mp = NULL;
235 }
236 return (error);
237}
238
239/*
240 * A new Ethernet interface has been attached.
241 * Create a new node for it, etc.
242 */
243static void
244ng_ether_attach(struct ifnet *ifp)
245{
246 char name[IFNAMSIZ + 1];
247 priv_p priv;
248 node_p node;
249
250 /* Create node */
251 KASSERT(!IFP2NG(ifp), ("%s: node already exists?", __FUNCTION__));
252 snprintf(name, sizeof(name), "%s%d", ifp->if_name, ifp->if_unit);
253 if (ng_make_node_common(&ng_ether_typestruct, &node) != 0) {
254 log(LOG_ERR, "%s: can't %s for %s\n",
255 __FUNCTION__, "create node", name);
256 return;
257 }
258
259 /* Allocate private data */
260 MALLOC(priv, priv_p, sizeof(*priv), M_NETGRAPH, M_NOWAIT);
261 if (priv == NULL) {
262 log(LOG_ERR, "%s: can't %s for %s\n",
263 __FUNCTION__, "allocate memory", name);
264 ng_unref(node);
265 return;
266 }
267 bzero(priv, sizeof(*priv));
268 node->private = priv;
269 priv->ifp = ifp;
270 IFP2NG(ifp) = node;
271
272 /* Try to give the node the same name as the interface */
273 if (ng_name_node(node, name) != 0) {
274 log(LOG_WARNING, "%s: can't name node %s\n",
275 __FUNCTION__, name);
276 }
277}
278
279/*
280 * An Ethernet interface is being detached.
281 * Destroy its node.
282 */
283static void
284ng_ether_detach(struct ifnet *ifp)
285{
286 const node_p node = IFP2NG(ifp);
287 priv_p priv;
288
289 if (node == NULL) /* no node (why not?), ignore */
290 return;
291 ng_rmnode(node); /* break all links to other nodes */
292 IFP2NG(ifp) = NULL; /* detach node from interface */
293 priv = node->private; /* free node private info */
294 bzero(priv, sizeof(*priv));
295 FREE(priv, M_NETGRAPH);
296 node->private = NULL;
297 ng_unref(node); /* free node itself */
298}
299
300/*
301 * Optimization for gluing the Ethernet header back onto
302 * the front of an incoming packet.
303 */
304static int
305ng_ether_glueback_header(struct mbuf **mp, struct ether_header *eh)
306{
307 struct mbuf *m = *mp;
308 uintfptr_t room;
309 int error = 0;
310
311 /*
312 * Possibly the header is already on the front.
313 * If this is the case so just move the markers back
314 * to re-include it. We lucked out.
315 * This allows us to avoid a yucky m_pullup
316 * in later nodes if it works.
317 */
318 if (eh == mtod(m, struct ether_header *) - 1) {
319 m->m_len += sizeof(*eh);
320 m->m_data -= sizeof(*eh);
321 m->m_pkthdr.len += sizeof(*eh);
322 goto done;
323 }
324
325 /*
326 * Alternatively there may be room even though
327 * it is stored somewhere else. If so, copy it in.
328 * This only safe because we KNOW that this packet has
329 * just been generated by an ethernet card, so there are
330 * no aliases to the buffer (not so for outgoing packets).
331 * Nearly all ethernet cards will end up producing mbufs
332 * that fall into these cases. So we are not optimizing
333 * contorted cases.
334 */
335 if ((m->m_flags & M_EXT) != 0) {
336 room = mtod(m, caddr_t) - m->m_ext.ext_buf;
337 if (room > m->m_ext.ext_size) /* garbage, fail immediately */
338 room = 0;
339 } else
340 room = mtod(m, caddr_t) - m->m_pktdat;
341
342 /*
343 * If we have room, just copy it and adjust
344 */
345 if (room >= sizeof(*eh)) {
346 m->m_len += sizeof(*eh);
347 m->m_data -= sizeof(*eh);
348 m->m_pkthdr.len += sizeof(*eh);
349 goto copy;
350 }
351
352 /*
353 * Doing anything more is likely to get more
354 * expensive than it's worth..
355 * it's probable that everything else is in one
356 * big lump. The next node will do an m_pullup()
357 * for exactly the amount of data it needs and
358 * hopefully everything after that will not
359 * need one. So let's just use M_PREPEND.
360 */
361 M_PREPEND(m, sizeof (*eh), M_DONTWAIT);
362 if (m == NULL) {
363 error = ENOBUFS;
364 goto done;
365 }
366
367copy:
368 /* Copy header and return (possibly new) mbuf */
369 bcopy((caddr_t)eh, mtod(m, struct ether_header *), sizeof(*eh));
370done:
371 *mp = m;
372 return error;
373}
374
375/******************************************************************
376 NETGRAPH NODE METHODS
377******************************************************************/
378
379/*
380 * It is not possible or allowable to create a node of this type.
381 * Nodes get created when the interface is attached (or, when
382 * this node type's KLD is loaded).
383 */
384static int
385ng_ether_constructor(node_p *nodep)
386{
387 return (EINVAL);
388}
389
390/*
391 * Check for attaching a new hook.
392 */
393static int
394ng_ether_newhook(node_p node, hook_p hook, const char *name)
395{
396 const priv_p priv = node->private;
397 u_char orphan = priv->lowerOrphan;
398 hook_p *hookptr;
399
400 /* Divert hook is an alias for lower */
401 if (strcmp(name, NG_ETHER_HOOK_DIVERT) == 0)
402 name = NG_ETHER_HOOK_LOWER;
403
404 /* Which hook? */
405 if (strcmp(name, NG_ETHER_HOOK_UPPER) == 0)
406 hookptr = &priv->upper;
407 else if (strcmp(name, NG_ETHER_HOOK_LOWER) == 0) {
408 hookptr = &priv->lower;
409 orphan = 0;
410 } else if (strcmp(name, NG_ETHER_HOOK_ORPHAN) == 0) {
411 hookptr = &priv->lower;
412 orphan = 1;
413 } else
414 return (EINVAL);
415
416 /* Check if already connected (shouldn't be, but doesn't hurt) */
417 if (*hookptr != NULL)
418 return (EISCONN);
419
420 /* OK */
421 *hookptr = hook;
422 priv->lowerOrphan = orphan;
423 return (0);
424}
425
426/*
427 * Receive an incoming control message.
428 */
429static int
430ng_ether_rcvmsg(node_p node, struct ng_mesg *msg, const char *retaddr,
431 struct ng_mesg **rptr, hook_p lasthook)
432{
433 const priv_p priv = node->private;
434 struct ng_mesg *resp = NULL;
435 int error = 0;
436
437 switch (msg->header.typecookie) {
438 case NGM_ETHER_COOKIE:
439 switch (msg->header.cmd) {
440 case NGM_ETHER_GET_IFNAME:
441 NG_MKRESPONSE(resp, msg, IFNAMSIZ + 1, M_NOWAIT);
442 if (resp == NULL) {
443 error = ENOMEM;
444 break;
445 }
446 snprintf(resp->data, IFNAMSIZ + 1,
447 "%s%d", priv->ifp->if_name, priv->ifp->if_unit);
448 break;
449 case NGM_ETHER_GET_IFINDEX:
450 NG_MKRESPONSE(resp, msg, sizeof(u_int32_t), M_NOWAIT);
451 if (resp == NULL) {
452 error = ENOMEM;
453 break;
454 }
455 *((u_int32_t *)resp->data) = priv->ifp->if_index;
456 break;
457 default:
458 error = EINVAL;
459 break;
460 }
461 break;
462 default:
463 error = EINVAL;
464 break;
465 }
466 if (rptr)
467 *rptr = resp;
468 else if (resp != NULL)
469 FREE(resp, M_NETGRAPH);
470 FREE(msg, M_NETGRAPH);
471 return (error);
472}
473
474/*
475 * Receive data on a hook.
476 */
477static int
478ng_ether_rcvdata(hook_p hook, struct mbuf *m, meta_p meta,
479 struct mbuf **ret_m, meta_p *ret_meta)
480{
481 const node_p node = hook->node;
482 const priv_p priv = node->private;
483
484 if (hook == priv->lower)
485 return ng_ether_rcv_lower(node, m, meta);
486 if (hook == priv->upper)
487 return ng_ether_rcv_upper(node, m, meta);
488 panic("%s: weird hook", __FUNCTION__);
489}
490
491/*
492 * Handle an mbuf received on the "lower" hook.
493 */
494static int
495ng_ether_rcv_lower(node_p node, struct mbuf *m, meta_p meta)
496{
497 const priv_p priv = node->private;
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