2 * ng_etf.c Ethertype filter
6 * Copyright (c) 2001, FreeBSD Incorporated
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
12 * 1. Redistributions of source code must retain the above copyright
13 * notice unmodified, this list of conditions, and the following
15 * 2. Redistributions in binary form must reproduce the above copyright
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17 * documentation and/or other materials provided with the distribution.
19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * Author: Julian Elischer <julian@freebsd.org>
33 * $FreeBSD: src/sys/netgraph/ng_etf.c,v 1.9 2005/03/14 20:49:48 glebius Exp $
34 * $DragonFly: src/sys/netgraph7/ng_etf.c,v 1.2 2008/06/26 23:05:35 dillon Exp $
37 #include <sys/param.h>
38 #include <sys/systm.h>
39 #include <sys/kernel.h>
41 #include <sys/malloc.h>
42 #include <sys/ctype.h>
43 #include <sys/errno.h>
44 #include <sys/queue.h>
45 #include <sys/syslog.h>
47 #include <net/ethernet.h>
49 #include "ng_message.h"
54 /* If you do complicated mallocs you may want to do this */
55 /* and use it for your mallocs */
56 #ifdef NG_SEPARATE_MALLOC
57 static MALLOC_DEFINE(M_NETGRAPH_ETF, "netgraph_etf", "netgraph etf node ");
59 #define M_NETGRAPH_ETF M_NETGRAPH
63 * This section contains the netgraph method declarations for the
64 * etf node. These methods define the netgraph 'type'.
67 static ng_constructor_t ng_etf_constructor;
68 static ng_rcvmsg_t ng_etf_rcvmsg;
69 static ng_shutdown_t ng_etf_shutdown;
70 static ng_newhook_t ng_etf_newhook;
71 static ng_rcvdata_t ng_etf_rcvdata; /* note these are both ng_rcvdata_t */
72 static ng_disconnect_t ng_etf_disconnect;
74 /* Parse type for struct ng_etfstat */
75 static const struct ng_parse_struct_field ng_etf_stat_type_fields[]
76 = NG_ETF_STATS_TYPE_INFO;
77 static const struct ng_parse_type ng_etf_stat_type = {
78 &ng_parse_struct_type,
79 &ng_etf_stat_type_fields
81 /* Parse type for struct ng_setfilter */
82 static const struct ng_parse_struct_field ng_etf_filter_type_fields[]
83 = NG_ETF_FILTER_TYPE_INFO;
84 static const struct ng_parse_type ng_etf_filter_type = {
85 &ng_parse_struct_type,
86 &ng_etf_filter_type_fields
89 /* List of commands and how to convert arguments to/from ASCII */
90 static const struct ng_cmdlist ng_etf_cmdlist[] = {
102 &ng_parse_int32_type,
115 /* Netgraph node type descriptor */
116 static struct ng_type typestruct = {
117 .version = NG_ABI_VERSION,
118 .name = NG_ETF_NODE_TYPE,
119 .constructor = ng_etf_constructor,
120 .rcvmsg = ng_etf_rcvmsg,
121 .shutdown = ng_etf_shutdown,
122 .newhook = ng_etf_newhook,
123 .rcvdata = ng_etf_rcvdata,
124 .disconnect = ng_etf_disconnect,
125 .cmdlist = ng_etf_cmdlist,
127 NETGRAPH_INIT(etf, &typestruct);
129 /* Information we store for each hook on each node */
130 struct ETF_hookinfo {
135 LIST_ENTRY(filter) next;
136 u_int16_t ethertype; /* network order ethertype */
137 hook_p match_hook; /* Hook to use on a match */
140 #define HASHSIZE 16 /* Dont change this without changing HASH() */
141 #define HASH(et) ((((et)>>12)+((et)>>8)+((et)>>4)+(et)) & 0x0f)
142 LIST_HEAD(filterhead, filter);
144 /* Information we store for each node */
146 struct ETF_hookinfo downstream_hook;
147 struct ETF_hookinfo nomatch_hook;
148 node_p node; /* back pointer to node */
149 u_int packets_in; /* packets in from downstream */
150 u_int packets_out; /* packets out towards downstream */
152 struct filterhead hashtable[HASHSIZE];
154 typedef struct ETF *etf_p;
156 static struct filter *
157 ng_etf_findentry(etf_p etfp, u_int16_t ethertype)
159 struct filterhead *chain = etfp->hashtable + HASH(ethertype);
163 LIST_FOREACH(fil, chain, next) {
164 if (fil->ethertype == ethertype) {
173 * Allocate the private data structure. The generic node has already
174 * been created. Link them together. We arrive with a reference to the node
175 * i.e. the reference count is incremented for us already.
178 ng_etf_constructor(node_p node)
183 /* Initialize private descriptor */
184 MALLOC(privdata, etf_p, sizeof(*privdata), M_NETGRAPH_ETF,
185 M_WAITOK | M_NULLOK | M_ZERO);
186 if (privdata == NULL)
188 for (i = 0; i < HASHSIZE; i++) {
189 LIST_INIT((privdata->hashtable + i));
192 /* Link structs together; this counts as our one reference to node */
193 NG_NODE_SET_PRIVATE(node, privdata);
194 privdata->node = node;
199 * Give our ok for a hook to be added...
200 * All names are ok. Two names are special.
203 ng_etf_newhook(node_p node, hook_p hook, const char *name)
205 const etf_p etfp = NG_NODE_PRIVATE(node);
206 struct ETF_hookinfo *hpriv;
208 if (strcmp(name, NG_ETF_HOOK_DOWNSTREAM) == 0) {
209 etfp->downstream_hook.hook = hook;
210 NG_HOOK_SET_PRIVATE(hook, &etfp->downstream_hook);
211 etfp->packets_in = 0;
212 etfp->packets_out = 0;
213 } else if (strcmp(name, NG_ETF_HOOK_NOMATCH) == 0) {
214 etfp->nomatch_hook.hook = hook;
215 NG_HOOK_SET_PRIVATE(hook, &etfp->nomatch_hook);
218 * Any other hook name is valid and can
219 * later be associated with a filter rule.
221 MALLOC(hpriv, struct ETF_hookinfo *, sizeof(*hpriv),
222 M_NETGRAPH_ETF, M_WAITOK | M_NULLOK | M_ZERO);
227 NG_HOOK_SET_PRIVATE(hook, hpriv);
234 * Get a netgraph control message.
235 * We actually recieve a queue item that has a pointer to the message.
236 * If we free the item, the message will be freed too, unless we remove
237 * it from the item using NGI_GET_MSG();
238 * The return address is also stored in the item, as an ng_ID_t,
239 * accessible as NGI_RETADDR(item);
240 * Check it is one we understand. If needed, send a response.
241 * We could save the address for an async action later, but don't here.
242 * Always free the message.
243 * The response should be in a malloc'd region that the caller can 'free'.
244 * The NG_MKRESPONSE macro does all this for us.
245 * A response is not required.
246 * Theoretically you could respond defferently to old message types if
247 * the cookie in the header didn't match what we consider to be current
248 * (so that old userland programs could continue to work).
251 ng_etf_rcvmsg(node_p node, item_p item, hook_p lasthook)
253 const etf_p etfp = NG_NODE_PRIVATE(node);
254 struct ng_mesg *resp = NULL;
258 NGI_GET_MSG(item, msg);
259 /* Deal with message according to cookie and command */
260 switch (msg->header.typecookie) {
262 switch (msg->header.cmd) {
263 case NGM_ETF_GET_STATUS:
265 struct ng_etfstat *stats;
267 NG_MKRESPONSE(resp, msg, sizeof(*stats), M_WAITOK | M_NULLOK);
272 stats = (struct ng_etfstat *) resp->data;
273 stats->packets_in = etfp->packets_in;
274 stats->packets_out = etfp->packets_out;
277 case NGM_ETF_SET_FLAG:
278 if (msg->header.arglen != sizeof(u_int32_t)) {
282 etfp->flags = *((u_int32_t *) msg->data);
284 case NGM_ETF_SET_FILTER:
286 struct ng_etffilter *f;
290 /* Check message long enough for this command */
291 if (msg->header.arglen != sizeof(*f)) {
296 /* Make sure hook referenced exists */
297 f = (struct ng_etffilter *)msg->data;
298 hook = ng_findhook(node, f->matchhook);
304 /* and is not the downstream hook */
305 if (hook == etfp->downstream_hook.hook) {
310 /* Check we don't already trap this ethertype */
311 if (ng_etf_findentry(etfp,
312 htons(f->ethertype))) {
318 * Ok, make the filter and put it in the
319 * hashtable ready for matching.
321 MALLOC(fil, struct filter *, sizeof(*fil),
322 M_NETGRAPH_ETF, M_WAITOK | M_NULLOK | M_ZERO);
328 fil->match_hook = hook;
329 fil->ethertype = htons(f->ethertype);
330 LIST_INSERT_HEAD( etfp->hashtable
331 + HASH(fil->ethertype),
336 error = EINVAL; /* unknown command */
341 error = EINVAL; /* unknown cookie type */
345 /* Take care of synchronous response, if any */
346 NG_RESPOND_MSG(error, node, item, resp);
347 /* Free the message and return */
353 * Receive data, and do something with it.
354 * Actually we receive a queue item which holds the data.
355 * If we free the item it will also free the data unless we have previously
356 * disassociated it using the NGI_GET_etf() macro.
357 * Possibly send it out on another link after processing.
358 * Possibly do something different if it comes from different
359 * hooks. The caller will never free m , so if we use up this data
360 * or abort we must free it.
362 * If we want, we may decide to force this data to be queued and reprocessed
363 * at the netgraph NETISR time.
364 * We would do that by setting the HK_QUEUE flag on our hook. We would do that
365 * in the connect() method.
368 ng_etf_rcvdata(hook_p hook, item_p item )
370 const etf_p etfp = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
371 struct ether_header *eh;
377 if (NG_HOOK_PRIVATE(hook) == NULL) { /* Shouldn't happen but.. */
382 * Everything not from the downstream hook goes to the
383 * downstream hook. But only if it matches the ethertype
384 * of the source hook. Un matching must go to/from 'nomatch'.
387 /* Make sure we have an entire header */
389 if (m->m_len < sizeof(*eh) ) {
390 m = m_pullup(m, sizeof(*eh));
397 eh = mtod(m, struct ether_header *);
398 ethertype = eh->ether_type;
399 fil = ng_etf_findentry(etfp, ethertype);
402 * if from downstream, select between a match hook or
405 if (hook == etfp->downstream_hook.hook) {
407 if (fil && fil->match_hook) {
408 NG_FWD_NEW_DATA(error, item, fil->match_hook, m);
410 NG_FWD_NEW_DATA(error, item,etfp->nomatch_hook.hook, m);
414 * It must be heading towards the downstream.
415 * Check that it's ethertype matches
416 * the filters for it's input hook.
417 * If it doesn't have one, check it's from nomatch.
419 if ((fil && (fil->match_hook != hook))
420 || ((fil == NULL) && (hook != etfp->nomatch_hook.hook))) {
425 NG_FWD_NEW_DATA( error, item, etfp->downstream_hook.hook, m);
434 * Do local shutdown processing..
435 * All our links and the name have already been removed.
438 ng_etf_shutdown(node_p node)
440 const etf_p privdata = NG_NODE_PRIVATE(node);
442 NG_NODE_SET_PRIVATE(node, NULL);
443 NG_NODE_UNREF(privdata->node);
444 FREE(privdata, M_NETGRAPH_ETF);
451 * For this type, removal of the last link destroys the node
454 ng_etf_disconnect(hook_p hook)
456 const etf_p etfp = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
458 struct filter *fil1, *fil2;
460 /* purge any rules that refer to this filter */
461 for (i = 0; i < HASHSIZE; i++) {
462 fil1 = LIST_FIRST(&etfp->hashtable[i]);
463 while (fil1 != NULL) {
464 fil2 = LIST_NEXT(fil1, next);
465 if (fil1->match_hook == hook) {
466 LIST_REMOVE(fil1, next);
467 FREE(fil1, M_NETGRAPH_ETF);
473 /* If it's not one of the special hooks, then free it */
474 if (hook == etfp->downstream_hook.hook) {
475 etfp->downstream_hook.hook = NULL;
476 } else if (hook == etfp->nomatch_hook.hook) {
477 etfp->nomatch_hook.hook = NULL;
479 if (NG_HOOK_PRIVATE(hook)) /* Paranoia */
480 FREE(NG_HOOK_PRIVATE(hook), M_NETGRAPH_ETF);
483 NG_HOOK_SET_PRIVATE(hook, NULL);
485 if ((NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0)
486 && (NG_NODE_IS_VALID(NG_HOOK_NODE(hook)))) /* already shutting down? */
487 ng_rmnode_self(NG_HOOK_NODE(hook));