6 * Copyright (c) 1999 Whistle Communications, Inc.
9 * Subject to the following obligations and disclaimer of warranty, use and
10 * redistribution of this software, in source or object code forms, with or
11 * without modifications are expressly permitted by Whistle Communications;
12 * provided, however, that:
13 * 1. Any and all reproductions of the source or object code must include the
14 * copyright notice above and the following disclaimer of warranties; and
15 * 2. No rights are granted, in any manner or form, to use Whistle
16 * Communications, Inc. trademarks, including the mark "WHISTLE
17 * COMMUNICATIONS" on advertising, endorsements, or otherwise except as
18 * such appears in the above copyright notice or in the software.
20 * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
21 * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
22 * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
23 * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
24 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
25 * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
26 * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
27 * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
28 * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
29 * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
30 * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
31 * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
32 * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
33 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
34 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
35 * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
38 * Author: Archie Cobbs <archie@freebsd.org>
40 * $FreeBSD: src/sys/netgraph/ng_bpf.c,v 1.24 2008/02/04 19:26:53 mav Exp $
41 * $DragonFly: src/sys/netgraph7/ng_bpf.c,v 1.2 2008/06/26 23:05:35 dillon Exp $
42 * $Whistle: ng_bpf.c,v 1.3 1999/12/03 20:30:23 archie Exp $
46 * BPF NETGRAPH NODE TYPE
48 * This node type accepts any number of hook connections. With each hook
49 * is associated a bpf(4) filter program, and two hook names (each possibly
50 * the empty string). Incoming packets are compared against the filter;
51 * matching packets are delivered out the first named hook (or dropped if
52 * the empty string), and non-matching packets are delivered out the second
53 * named hook (or dropped if the empty string).
55 * Each hook also keeps statistics about how many packets have matched, etc.
60 #include <sys/param.h>
61 #include <sys/systm.h>
62 #include <sys/errno.h>
63 #include <sys/kernel.h>
64 #include <sys/malloc.h>
69 #include <net/bpf_jitter.h>
72 #include "ng_message.h"
77 #ifdef NG_SEPARATE_MALLOC
78 MALLOC_DEFINE(M_NETGRAPH_BPF, "netgraph_bpf", "netgraph bpf node ");
80 #define M_NETGRAPH_BPF M_NETGRAPH
83 #define OFFSETOF(s, e) ((char *)&((s *)0)->e - (char *)((s *)0))
85 #define ERROUT(x) do { error = (x); goto done; } while (0)
87 /* Per hook private info */
88 struct ng_bpf_hookinfo {
92 struct ng_bpf_hookprog *prog;
94 bpf_jit_filter *jit_prog;
96 struct ng_bpf_hookstat stats;
98 typedef struct ng_bpf_hookinfo *hinfo_p;
100 /* Netgraph methods */
101 static ng_constructor_t ng_bpf_constructor;
102 static ng_rcvmsg_t ng_bpf_rcvmsg;
103 static ng_shutdown_t ng_bpf_shutdown;
104 static ng_newhook_t ng_bpf_newhook;
105 static ng_rcvdata_t ng_bpf_rcvdata;
106 static ng_disconnect_t ng_bpf_disconnect;
108 /* Internal helper functions */
109 static int ng_bpf_setprog(hook_p hook, const struct ng_bpf_hookprog *hp);
111 /* Parse type for one struct bfp_insn */
112 static const struct ng_parse_struct_field ng_bpf_insn_type_fields[] = {
113 { "code", &ng_parse_hint16_type },
114 { "jt", &ng_parse_uint8_type },
115 { "jf", &ng_parse_uint8_type },
116 { "k", &ng_parse_uint32_type },
119 static const struct ng_parse_type ng_bpf_insn_type = {
120 &ng_parse_struct_type,
121 &ng_bpf_insn_type_fields
124 /* Parse type for the field 'bpf_prog' in struct ng_bpf_hookprog */
126 ng_bpf_hookprogary_getLength(const struct ng_parse_type *type,
127 const u_char *start, const u_char *buf)
129 const struct ng_bpf_hookprog *hp;
131 hp = (const struct ng_bpf_hookprog *)
132 (buf - OFFSETOF(struct ng_bpf_hookprog, bpf_prog));
133 return hp->bpf_prog_len;
136 static const struct ng_parse_array_info ng_bpf_hookprogary_info = {
138 &ng_bpf_hookprogary_getLength,
141 static const struct ng_parse_type ng_bpf_hookprogary_type = {
142 &ng_parse_array_type,
143 &ng_bpf_hookprogary_info
146 /* Parse type for struct ng_bpf_hookprog */
147 static const struct ng_parse_struct_field ng_bpf_hookprog_type_fields[]
148 = NG_BPF_HOOKPROG_TYPE_INFO(&ng_bpf_hookprogary_type);
149 static const struct ng_parse_type ng_bpf_hookprog_type = {
150 &ng_parse_struct_type,
151 &ng_bpf_hookprog_type_fields
154 /* Parse type for struct ng_bpf_hookstat */
155 static const struct ng_parse_struct_field ng_bpf_hookstat_type_fields[]
156 = NG_BPF_HOOKSTAT_TYPE_INFO;
157 static const struct ng_parse_type ng_bpf_hookstat_type = {
158 &ng_parse_struct_type,
159 &ng_bpf_hookstat_type_fields
162 /* List of commands and how to convert arguments to/from ASCII */
163 static const struct ng_cmdlist ng_bpf_cmdlist[] = {
168 &ng_bpf_hookprog_type,
175 &ng_parse_hookbuf_type,
176 &ng_bpf_hookprog_type
182 &ng_parse_hookbuf_type,
183 &ng_bpf_hookstat_type
189 &ng_parse_hookbuf_type,
194 NGM_BPF_GETCLR_STATS,
196 &ng_parse_hookbuf_type,
197 &ng_bpf_hookstat_type
202 /* Netgraph type descriptor */
203 static struct ng_type typestruct = {
204 .version = NG_ABI_VERSION,
205 .name = NG_BPF_NODE_TYPE,
206 .constructor = ng_bpf_constructor,
207 .rcvmsg = ng_bpf_rcvmsg,
208 .shutdown = ng_bpf_shutdown,
209 .newhook = ng_bpf_newhook,
210 .rcvdata = ng_bpf_rcvdata,
211 .disconnect = ng_bpf_disconnect,
212 .cmdlist = ng_bpf_cmdlist,
214 NETGRAPH_INIT(bpf, &typestruct);
216 /* Default BPF program for a hook that matches nothing */
217 static const struct ng_bpf_hookprog ng_bpf_default_prog = {
218 { '\0' }, /* to be filled in at hook creation time */
222 { BPF_STMT(BPF_RET+BPF_K, 0) }
228 * We don't keep any per-node private data
229 * We go via the hooks.
232 ng_bpf_constructor(node_p node)
234 NG_NODE_SET_PRIVATE(node, NULL);
239 * Callback functions to be used by NG_NODE_FOREACH_HOOK() macro.
242 ng_bpf_addrefs(hook_p hook, void* arg)
244 hinfo_p hip = NG_HOOK_PRIVATE(hook);
245 hook_p h = (hook_p)arg;
247 if (strcmp(hip->prog->ifMatch, NG_HOOK_NAME(h)) == 0)
249 if (strcmp(hip->prog->ifNotMatch, NG_HOOK_NAME(h)) == 0)
255 ng_bpf_remrefs(hook_p hook, void* arg)
257 hinfo_p hip = NG_HOOK_PRIVATE(hook);
258 hook_p h = (hook_p)arg;
262 if (hip->nomatch == h)
271 ng_bpf_newhook(node_p node, hook_p hook, const char *name)
277 /* Create hook private structure */
278 MALLOC(hip, hinfo_p, sizeof(*hip), M_NETGRAPH_BPF, M_WAITOK | M_NULLOK | M_ZERO);
282 NG_HOOK_SET_PRIVATE(hook, hip);
284 /* Add our reference into other hooks data. */
285 NG_NODE_FOREACH_HOOK(node, ng_bpf_addrefs, hook, tmp);
287 /* Attach the default BPF program */
288 if ((error = ng_bpf_setprog(hook, &ng_bpf_default_prog)) != 0) {
289 FREE(hip, M_NETGRAPH_BPF);
290 NG_HOOK_SET_PRIVATE(hook, NULL);
295 strlcpy(hip->prog->thisHook, name, sizeof(hip->prog->thisHook));
300 * Receive a control message
303 ng_bpf_rcvmsg(node_p node, item_p item, hook_p lasthook)
306 struct ng_mesg *resp = NULL;
309 NGI_GET_MSG(item, msg);
310 switch (msg->header.typecookie) {
312 switch (msg->header.cmd) {
313 case NGM_BPF_SET_PROGRAM:
315 struct ng_bpf_hookprog *const
316 hp = (struct ng_bpf_hookprog *)msg->data;
320 if (msg->header.arglen < sizeof(*hp)
321 || msg->header.arglen
322 != NG_BPF_HOOKPROG_SIZE(hp->bpf_prog_len))
326 if ((hook = ng_findhook(node, hp->thisHook)) == NULL)
329 /* Set new program */
330 if ((error = ng_bpf_setprog(hook, hp)) != 0)
335 case NGM_BPF_GET_PROGRAM:
337 struct ng_bpf_hookprog *hp;
341 if (msg->header.arglen == 0)
343 msg->data[msg->header.arglen - 1] = '\0';
346 if ((hook = ng_findhook(node, msg->data)) == NULL)
350 hp = ((hinfo_p)NG_HOOK_PRIVATE(hook))->prog;
351 NG_MKRESPONSE(resp, msg,
352 NG_BPF_HOOKPROG_SIZE(hp->bpf_prog_len), M_WAITOK | M_NULLOK);
355 bcopy(hp, resp->data,
356 NG_BPF_HOOKPROG_SIZE(hp->bpf_prog_len));
360 case NGM_BPF_GET_STATS:
361 case NGM_BPF_CLR_STATS:
362 case NGM_BPF_GETCLR_STATS:
364 struct ng_bpf_hookstat *stats;
368 if (msg->header.arglen == 0)
370 msg->data[msg->header.arglen - 1] = '\0';
373 if ((hook = ng_findhook(node, msg->data)) == NULL)
375 stats = &((hinfo_p)NG_HOOK_PRIVATE(hook))->stats;
377 /* Build response (if desired) */
378 if (msg->header.cmd != NGM_BPF_CLR_STATS) {
380 msg, sizeof(*stats), M_WAITOK | M_NULLOK);
383 bcopy(stats, resp->data, sizeof(*stats));
386 /* Clear stats (if desired) */
387 if (msg->header.cmd != NGM_BPF_GET_STATS)
388 bzero(stats, sizeof(*stats));
402 NG_RESPOND_MSG(error, node, item, resp);
408 * Receive data on a hook
410 * Apply the filter, and then drop or forward packet as appropriate.
413 ng_bpf_rcvdata(hook_p hook, item_p item)
415 const hinfo_p hip = NG_HOOK_PRIVATE(hook);
417 int needfree = 0, error = 0, usejit = 0;
424 m = NGI_M(item); /* 'item' still owns it.. we are peeking */
425 totlen = m->m_pkthdr.len;
426 /* Update stats on incoming hook. XXX Can we do 64 bits atomically? */
427 /* atomic_add_int64(&hip->stats.recvFrames, 1); */
428 /* atomic_add_int64(&hip->stats.recvOctets, totlen); */
429 hip->stats.recvFrames++;
430 hip->stats.recvOctets += totlen;
432 /* Don't call bpf_filter() with totlen == 0! */
439 if (bpf_jitter_enable != 0 && hip->jit_prog != NULL)
443 /* Need to put packet in contiguous memory for bpf */
444 if (m->m_next != NULL && totlen > MHLEN) {
446 MALLOC(data, u_char *, totlen, M_NETGRAPH_BPF, M_NOWAIT);
452 m_copydata(m, 0, totlen, (caddr_t)data);
455 if (m->m_next != NULL) {
456 NGI_M(item) = m = m_pullup(m, totlen);
462 data = mtod(m, u_char *);
465 /* Run packet through filter */
468 len = (*(hip->jit_prog->func))(data, totlen, totlen);
472 len = bpf_filter(hip->prog->bpf_prog, data, totlen, totlen);
474 len = bpf_filter(hip->prog->bpf_prog, (u_char *)m, totlen, 0);
476 FREE(data, M_NETGRAPH_BPF);
478 /* See if we got a match and find destination hook */
482 /* XXX atomically? */
483 hip->stats.recvMatchFrames++;
484 hip->stats.recvMatchOctets += totlen;
486 /* Truncate packet length if required by the filter */
487 /* Assume this never changes m */
489 m_adj(m, -(totlen - len));
500 /* Deliver frame out destination hook */
501 dhip = NG_HOOK_PRIVATE(dest);
502 dhip->stats.xmitOctets += totlen;
503 dhip->stats.xmitFrames++;
504 NG_FWD_ITEM_HOOK(error, item, dest);
509 * Shutdown processing
512 ng_bpf_shutdown(node_p node)
522 ng_bpf_disconnect(hook_p hook)
524 const node_p node = NG_HOOK_NODE(hook);
525 const hinfo_p hip = NG_HOOK_PRIVATE(hook);
528 KASSERT(hip != NULL, ("%s: null info", __func__));
530 /* Remove our reference from other hooks data. */
531 NG_NODE_FOREACH_HOOK(node, ng_bpf_remrefs, hook, tmp);
533 FREE(hip->prog, M_NETGRAPH_BPF);
535 if (hip->jit_prog != NULL)
536 bpf_destroy_jit_filter(hip->jit_prog);
538 FREE(hip, M_NETGRAPH_BPF);
539 if ((NG_NODE_NUMHOOKS(node) == 0) &&
540 (NG_NODE_IS_VALID(node))) {
541 ng_rmnode_self(node);
546 /************************************************************************
548 ************************************************************************/
551 * Set the BPF program associated with a hook
554 ng_bpf_setprog(hook_p hook, const struct ng_bpf_hookprog *hp0)
556 const hinfo_p hip = NG_HOOK_PRIVATE(hook);
557 struct ng_bpf_hookprog *hp;
559 bpf_jit_filter *jit_prog;
563 /* Check program for validity */
564 if (!bpf_validate(hp0->bpf_prog, hp0->bpf_prog_len))
567 /* Make a copy of the program */
568 size = NG_BPF_HOOKPROG_SIZE(hp0->bpf_prog_len);
569 MALLOC(hp, struct ng_bpf_hookprog *, size, M_NETGRAPH_BPF, M_NOWAIT);
572 bcopy(hp0, hp, size);
574 jit_prog = bpf_jitter(hp->bpf_prog, hp->bpf_prog_len);
577 /* Free previous program, if any, and assign new one */
578 if (hip->prog != NULL)
579 FREE(hip->prog, M_NETGRAPH_BPF);
582 if (hip->jit_prog != NULL)
583 bpf_destroy_jit_filter(hip->jit_prog);
584 hip->jit_prog = jit_prog;
587 /* Prepare direct references on target hooks. */
588 hip->match = ng_findhook(NG_HOOK_NODE(hook), hip->prog->ifMatch);
589 hip->nomatch = ng_findhook(NG_HOOK_NODE(hook), hip->prog->ifNotMatch);