1 /*-
2 * Copyright (c) 2003 IPNET Internet Communication Company
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 *
26 * Author: Ruslan Ermilov <ru@FreeBSD.org>
27 *
28 * $FreeBSD: src/sys/netgraph/ng_vlan.c,v 1.5 2007/06/11 15:29:02 imp Exp $
29 */
30
31 #include <sys/param.h>
32 #include <sys/errno.h>
33 #include <sys/kernel.h>
34 #include <sys/malloc.h>
35 #include <sys/mbuf.h>
36 #include <sys/queue.h>
37 #include <sys/socket.h>
38 #include <sys/systm.h>
39
40 #include <net/ethernet.h>
41 #include <net/if.h>
42 #include <net/if_vlan_var.h>
43
44 #include "ng_message.h"
45 #include "ng_parse.h"
46 #include "ng_vlan.h"
47 #include "netgraph.h"
48
49 static ng_constructor_t ng_vlan_constructor;
50 static ng_rcvmsg_t ng_vlan_rcvmsg;
51 static ng_shutdown_t ng_vlan_shutdown;
52 static ng_newhook_t ng_vlan_newhook;
53 static ng_rcvdata_t ng_vlan_rcvdata;
54 static ng_disconnect_t ng_vlan_disconnect;
55
56 /* Parse type for struct ng_vlan_filter. */
57 static const struct ng_parse_struct_field ng_vlan_filter_fields[] =
58 NG_VLAN_FILTER_FIELDS;
59 static const struct ng_parse_type ng_vlan_filter_type = {
60 &ng_parse_struct_type,
61 &ng_vlan_filter_fields
62 };
63
64 static int
ng_vlan_getTableLength(const struct ng_parse_type * type,const u_char * start,const u_char * buf)65 ng_vlan_getTableLength(const struct ng_parse_type *type,
66 const u_char *start, const u_char *buf)
67 {
68 const struct ng_vlan_table *const table =
69 (const struct ng_vlan_table *)(buf - sizeof(u_int32_t));
70
71 return table->n;
72 }
73
74 /* Parse type for struct ng_vlan_table. */
75 static const struct ng_parse_array_info ng_vlan_table_array_info = {
76 &ng_vlan_filter_type,
77 ng_vlan_getTableLength
78 };
79 static const struct ng_parse_type ng_vlan_table_array_type = {
80 &ng_parse_array_type,
81 &ng_vlan_table_array_info
82 };
83 static const struct ng_parse_struct_field ng_vlan_table_fields[] =
84 NG_VLAN_TABLE_FIELDS;
85 static const struct ng_parse_type ng_vlan_table_type = {
86 &ng_parse_struct_type,
87 &ng_vlan_table_fields
88 };
89
90 /* List of commands and how to convert arguments to/from ASCII. */
91 static const struct ng_cmdlist ng_vlan_cmdlist[] = {
92 {
93 NGM_VLAN_COOKIE,
94 NGM_VLAN_ADD_FILTER,
95 "addfilter",
96 &ng_vlan_filter_type,
97 NULL
98 },
99 {
100 NGM_VLAN_COOKIE,
101 NGM_VLAN_DEL_FILTER,
102 "delfilter",
103 &ng_parse_hookbuf_type,
104 NULL
105 },
106 {
107 NGM_VLAN_COOKIE,
108 NGM_VLAN_GET_TABLE,
109 "gettable",
110 NULL,
111 &ng_vlan_table_type
112 },
113 { 0 }
114 };
115
116 static struct ng_type ng_vlan_typestruct = {
117 .version = NG_ABI_VERSION,
118 .name = NG_VLAN_NODE_TYPE,
119 .constructor = ng_vlan_constructor,
120 .rcvmsg = ng_vlan_rcvmsg,
121 .shutdown = ng_vlan_shutdown,
122 .newhook = ng_vlan_newhook,
123 .rcvdata = ng_vlan_rcvdata,
124 .disconnect = ng_vlan_disconnect,
125 .cmdlist = ng_vlan_cmdlist,
126 };
127 NETGRAPH_INIT(vlan, &ng_vlan_typestruct);
128
129 struct filter {
130 LIST_ENTRY(filter) next;
131 u_int16_t vlan;
132 hook_p hook;
133 };
134
135 #define HASHSIZE 16
136 #define HASH(id) ((((id) >> 8) ^ ((id) >> 4) ^ (id)) & 0x0f)
137 LIST_HEAD(filterhead, filter);
138
139 typedef struct {
140 hook_p downstream_hook;
141 hook_p nomatch_hook;
142 struct filterhead hashtable[HASHSIZE];
143 u_int32_t nent;
144 } *priv_p;
145
146 static struct filter *
ng_vlan_findentry(priv_p priv,u_int16_t vlan)147 ng_vlan_findentry(priv_p priv, u_int16_t vlan)
148 {
149 struct filterhead *chain = &priv->hashtable[HASH(vlan)];
150 struct filter *f;
151
152 LIST_FOREACH(f, chain, next)
153 if (f->vlan == vlan)
154 return (f);
155 return (NULL);
156 }
157
158 static int
ng_vlan_constructor(node_p node)159 ng_vlan_constructor(node_p node)
160 {
161 priv_p priv;
162 int i;
163
164 priv = kmalloc(sizeof(*priv), M_NETGRAPH,
165 M_WAITOK | M_NULLOK | M_ZERO);
166 if (priv == NULL)
167 return (ENOMEM);
168 for (i = 0; i < HASHSIZE; i++)
169 LIST_INIT(&priv->hashtable[i]);
170 NG_NODE_SET_PRIVATE(node, priv);
171 return (0);
172 }
173
174 static int
ng_vlan_newhook(node_p node,hook_p hook,const char * name)175 ng_vlan_newhook(node_p node, hook_p hook, const char *name)
176 {
177 const priv_p priv = NG_NODE_PRIVATE(node);
178
179 if (strcmp(name, NG_VLAN_HOOK_DOWNSTREAM) == 0)
180 priv->downstream_hook = hook;
181 else if (strcmp(name, NG_VLAN_HOOK_NOMATCH) == 0)
182 priv->nomatch_hook = hook;
183 else {
184 /*
185 * Any other hook name is valid and can
186 * later be associated with a filter rule.
187 */
188 }
189 NG_HOOK_SET_PRIVATE(hook, NULL);
190 return (0);
191 }
192
193 static int
ng_vlan_rcvmsg(node_p node,item_p item,hook_p lasthook)194 ng_vlan_rcvmsg(node_p node, item_p item, hook_p lasthook)
195 {
196 const priv_p priv = NG_NODE_PRIVATE(node);
197 int error = 0;
198 struct ng_mesg *msg, *resp = NULL;
199 struct ng_vlan_filter *vf;
200 struct filter *f;
201 hook_p hook;
202 struct ng_vlan_table *t;
203 int i;
204
205 NGI_GET_MSG(item, msg);
206 /* Deal with message according to cookie and command. */
207 switch (msg->header.typecookie) {
208 case NGM_VLAN_COOKIE:
209 switch (msg->header.cmd) {
210 case NGM_VLAN_ADD_FILTER:
211 /* Check that message is long enough. */
212 if (msg->header.arglen != sizeof(*vf)) {
213 error = EINVAL;
214 break;
215 }
216 vf = (struct ng_vlan_filter *)msg->data;
217 /* Sanity check the VLAN ID value. */
218 if (vf->vlan & ~EVL_VLID_MASK) {
219 error = EINVAL;
220 break;
221 }
222 /* Check that a referenced hook exists. */
223 hook = ng_findhook(node, vf->hook);
224 if (hook == NULL) {
225 error = ENOENT;
226 break;
227 }
228 /* And is not one of the special hooks. */
229 if (hook == priv->downstream_hook ||
230 hook == priv->nomatch_hook) {
231 error = EINVAL;
232 break;
233 }
234 /* And is not already in service. */
235 if (NG_HOOK_PRIVATE(hook) != NULL) {
236 error = EEXIST;
237 break;
238 }
239 /* Check we don't already trap this VLAN. */
240 if (ng_vlan_findentry(priv, vf->vlan)) {
241 error = EEXIST;
242 break;
243 }
244 /* Create filter. */
245 f = kmalloc(sizeof(*f), M_NETGRAPH,
246 M_WAITOK | M_NULLOK | M_ZERO);
247 if (f == NULL) {
248 error = ENOMEM;
249 break;
250 }
251 /* Link filter and hook together. */
252 f->hook = hook;
253 f->vlan = vf->vlan;
254 NG_HOOK_SET_PRIVATE(hook, f);
255 /* Register filter in a hash table. */
256 LIST_INSERT_HEAD(
257 &priv->hashtable[HASH(f->vlan)], f, next);
258 priv->nent++;
259 break;
260 case NGM_VLAN_DEL_FILTER:
261 /* Check that message is long enough. */
262 if (msg->header.arglen != NG_HOOKSIZ) {
263 error = EINVAL;
264 break;
265 }
266 /* Check that hook exists and is active. */
267 hook = ng_findhook(node, (char *)msg->data);
268 if (hook == NULL ||
269 (f = NG_HOOK_PRIVATE(hook)) == NULL) {
270 error = ENOENT;
271 break;
272 }
273 /* Purge a rule that refers to this hook. */
274 NG_HOOK_SET_PRIVATE(hook, NULL);
275 LIST_REMOVE(f, next);
276 priv->nent--;
277 kfree(f, M_NETGRAPH);
278 break;
279 case NGM_VLAN_GET_TABLE:
280 NG_MKRESPONSE(resp, msg, sizeof(*t) +
281 priv->nent * sizeof(*t->filter), M_WAITOK | M_NULLOK);
282 if (resp == NULL) {
283 error = ENOMEM;
284 break;
285 }
286 t = (struct ng_vlan_table *)resp->data;
287 t->n = priv->nent;
288 vf = &t->filter[0];
289 for (i = 0; i < HASHSIZE; i++) {
290 LIST_FOREACH(f, &priv->hashtable[i], next) {
291 vf->vlan = f->vlan;
292 strncpy(vf->hook, NG_HOOK_NAME(f->hook),
293 NG_HOOKSIZ);
294 vf++;
295 }
296 }
297 break;
298 default: /* Unknown command. */
299 error = EINVAL;
300 break;
301 }
302 break;
303 case NGM_FLOW_COOKIE:
304 {
305 struct ng_mesg *copy;
306 struct filterhead *chain;
307 struct filter *f;
308
309 /*
310 * Flow control messages should come only
311 * from downstream.
312 */
313
314 if (lasthook == NULL)
315 break;
316 if (lasthook != priv->downstream_hook)
317 break;
318
319 /* Broadcast the event to all uplinks. */
320 for (i = 0, chain = priv->hashtable; i < HASHSIZE;
321 i++, chain++) {
322 LIST_FOREACH(f, chain, next) {
323 NG_COPYMESSAGE(copy, msg, M_WAITOK | M_NULLOK);
324 if (copy == NULL)
325 continue;
326 NG_SEND_MSG_HOOK(error, node, copy, f->hook, 0);
327 }
328 }
329
330 break;
331 }
332 default: /* Unknown type cookie. */
333 error = EINVAL;
334 break;
335 }
336 NG_RESPOND_MSG(error, node, item, resp);
337 NG_FREE_MSG(msg);
338 return (error);
339 }
340
341 static int
ng_vlan_rcvdata(hook_p hook,item_p item)342 ng_vlan_rcvdata(hook_p hook, item_p item)
343 {
344 const priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
345 struct ether_header *eh;
346 struct ether_vlan_header *evl = NULL;
347 int error;
348 u_int16_t vlan;
349 struct mbuf *m;
350 struct filter *f;
351
352 /* Make sure we have an entire header. */
353 NGI_GET_M(item, m);
354 if (m->m_len < sizeof(*eh) &&
355 (m = m_pullup(m, sizeof(*eh))) == NULL) {
356 NG_FREE_ITEM(item);
357 return (EINVAL);
358 }
359 eh = mtod(m, struct ether_header *);
360 if (hook == priv->downstream_hook) {
361 /*
362 * If from downstream, select between a match hook
363 * or the nomatch hook.
364 */
365 if (m->m_flags & M_VLANTAG ||
366 eh->ether_type == htons(ETHERTYPE_VLAN)) {
367 if (m->m_flags & M_VLANTAG) {
368 /*
369 * Packet is tagged, m contains a normal
370 * Ethernet frame; tag is stored out-of-band.
371 */
372 vlan = EVL_VLANOFTAG(m->m_pkthdr.ether_vtag);
373 } else {
374 if (m->m_len < sizeof(*evl) &&
375 (m = m_pullup(m, sizeof(*evl))) == NULL) {
376 NG_FREE_ITEM(item);
377 return (EINVAL);
378 }
379 evl = mtod(m, struct ether_vlan_header *);
380 vlan = EVL_VLANOFTAG(ntohs(evl->evl_tag));
381 }
382 if ((f = ng_vlan_findentry(priv, vlan)) != NULL) {
383 if (m->m_flags & M_VLANTAG) {
384 m->m_pkthdr.ether_vtag = 0;
385 m->m_flags &= ~M_VLANTAG;
386 } else {
387 evl->evl_encap_proto = evl->evl_proto;
388 bcopy(mtod(m, caddr_t),
389 mtod(m, caddr_t) +
390 ETHER_VLAN_ENCAP_LEN,
391 ETHER_HDR_LEN);
392 m_adj(m, ETHER_VLAN_ENCAP_LEN);
393 }
394 }
395 } else
396 f = NULL;
397 if (f != NULL)
398 NG_FWD_NEW_DATA(error, item, f->hook, m);
399 else
400 NG_FWD_NEW_DATA(error, item, priv->nomatch_hook, m);
401 } else {
402 /*
403 * It is heading towards the downstream.
404 * If from nomatch, pass it unmodified.
405 * Otherwise, do the VLAN encapsulation.
406 */
407 if (hook != priv->nomatch_hook) {
408 if ((f = NG_HOOK_PRIVATE(hook)) == NULL) {
409 NG_FREE_ITEM(item);
410 NG_FREE_M(m);
411 return (EOPNOTSUPP);
412 }
413 M_PREPEND(m, ETHER_VLAN_ENCAP_LEN, M_NOWAIT);
414 /* M_PREPEND takes care of m_len and m_pkthdr.len. */
415 if (m == NULL || (m->m_len < sizeof(*evl) &&
416 (m = m_pullup(m, sizeof(*evl))) == NULL)) {
417 NG_FREE_ITEM(item);
418 return (ENOMEM);
419 }
420 /*
421 * Transform the Ethernet header into an Ethernet header
422 * with 802.1Q encapsulation.
423 */
424 bcopy(mtod(m, char *) + ETHER_VLAN_ENCAP_LEN,
425 mtod(m, char *), ETHER_HDR_LEN);
426 evl = mtod(m, struct ether_vlan_header *);
427 evl->evl_proto = evl->evl_encap_proto;
428 evl->evl_encap_proto = htons(ETHERTYPE_VLAN);
429 evl->evl_tag = htons(f->vlan);
430 }
431 NG_FWD_NEW_DATA(error, item, priv->downstream_hook, m);
432 }
433 return (error);
434 }
435
436 static int
ng_vlan_shutdown(node_p node)437 ng_vlan_shutdown(node_p node)
438 {
439 const priv_p priv = NG_NODE_PRIVATE(node);
440
441 NG_NODE_SET_PRIVATE(node, NULL);
442 NG_NODE_UNREF(node);
443 kfree(priv, M_NETGRAPH);
444 return (0);
445 }
446
447 static int
ng_vlan_disconnect(hook_p hook)448 ng_vlan_disconnect(hook_p hook)
449 {
450 const priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
451 struct filter *f;
452
453 if (hook == priv->downstream_hook)
454 priv->downstream_hook = NULL;
455 else if (hook == priv->nomatch_hook)
456 priv->nomatch_hook = NULL;
457 else {
458 /* Purge a rule that refers to this hook. */
459 if ((f = NG_HOOK_PRIVATE(hook)) != NULL) {
460 LIST_REMOVE(f, next);
461 priv->nent--;
462 kfree(f, M_NETGRAPH);
463 }
464 }
465 NG_HOOK_SET_PRIVATE(hook, NULL);
466 if ((NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0) &&
467 (NG_NODE_IS_VALID(NG_HOOK_NODE(hook))))
468 ng_rmnode_self(NG_HOOK_NODE(hook));
469 return (0);
470 }
471