1
2/*
3 * ng_tee.c
4 *
5 * Copyright (c) 1996-1999 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 * Author: Julian Elischer <julian@freebsd.org>
38 *
39 * $FreeBSD: head/sys/netgraph/ng_tee.c 68876 2000-11-18 15:17:43Z dwmalone $
40 * $Whistle: ng_tee.c,v 1.18 1999/11/01 09:24:52 julian Exp $
41 */
42
43/*
44 * This node is like the tee(1) command and is useful for ``snooping.''
45 * It has 4 hooks: left, right, left2right, and right2left. Data
46 * entering from the right is passed to the left and duplicated on
47 * right2left, and data entering from the left is passed to the right
48 * and duplicated on left2right. Data entering from left2right is
49 * sent to right, and data from right2left to left.
50 */
51
52#include <sys/param.h>
53#include <sys/systm.h>
54#include <sys/errno.h>
55#include <sys/kernel.h>
56#include <sys/malloc.h>
57#include <sys/mbuf.h>
58#include <netgraph/ng_message.h>
59#include <netgraph/netgraph.h>
60#include <netgraph/ng_parse.h>
61#include <netgraph/ng_tee.h>
62
63/* Per hook info */
64struct hookinfo {
65 hook_p hook;
66 struct ng_tee_hookstat stats;
67};
68
69/* Per node info */
70struct privdata {
71 node_p node;
72 struct hookinfo left;
73 struct hookinfo right;
74 struct hookinfo left2right;
75 struct hookinfo right2left;
76};
77typedef struct privdata *sc_p;
78
79/* Netgraph methods */
80static ng_constructor_t ngt_constructor;
81static ng_rcvmsg_t ngt_rcvmsg;
82static ng_shutdown_t ngt_rmnode;
83static ng_newhook_t ngt_newhook;
84static ng_rcvdata_t ngt_rcvdata;
85static ng_disconnect_t ngt_disconnect;
86
87/* Parse type for struct ng_tee_hookstat */
88static const struct ng_parse_struct_info
89 ng_tee_hookstat_type_info = NG_TEE_HOOKSTAT_INFO;
90static const struct ng_parse_type ng_tee_hookstat_type = {
91 &ng_parse_struct_type,
92 &ng_tee_hookstat_type_info,
93};
94
95/* Parse type for struct ng_tee_stats */
96static const struct ng_parse_struct_info
97 ng_tee_stats_type_info = NG_TEE_STATS_INFO(&ng_tee_hookstat_type);
98static const struct ng_parse_type ng_tee_stats_type = {
99 &ng_parse_struct_type,
100 &ng_tee_stats_type_info,
101};
102
103/* List of commands and how to convert arguments to/from ASCII */
104static const struct ng_cmdlist ng_tee_cmds[] = {
105 {
106 NGM_TEE_COOKIE,
107 NGM_TEE_GET_STATS,
108 "getstats",
109 NULL,
110 &ng_tee_stats_type
111 },
112 {
113 NGM_TEE_COOKIE,
114 NGM_TEE_CLR_STATS,
115 "clrstats",
116 NULL,
117 NULL
118 },
119 {
120 NGM_TEE_COOKIE,
121 NGM_TEE_GETCLR_STATS,
122 "getclrstats",
123 NULL,
124 &ng_tee_stats_type
125 },
126 { 0 }
127};
128
129/* Netgraph type descriptor */
130static struct ng_type ng_tee_typestruct = {
131 NG_VERSION,
132 NG_TEE_NODE_TYPE,
133 NULL,
134 ngt_constructor,
135 ngt_rcvmsg,
136 ngt_rmnode,
137 ngt_newhook,
138 NULL,
139 NULL,
140 ngt_rcvdata,
141 ngt_rcvdata,
142 ngt_disconnect,
143 ng_tee_cmds
144};
145NETGRAPH_INIT(tee, &ng_tee_typestruct);
146
147/*
148 * Node constructor
149 */
150static int
151ngt_constructor(node_p *nodep)
152{
153 sc_p privdata;
154 int error = 0;
155
156 MALLOC(privdata, sc_p, sizeof(*privdata), M_NETGRAPH, M_NOWAIT|M_ZERO);
157 if (privdata == NULL)
158 return (ENOMEM);
159
160 if ((error = ng_make_node_common(&ng_tee_typestruct, nodep))) {
161 FREE(privdata, M_NETGRAPH);
162 return (error);
163 }
164 (*nodep)->private = privdata;
165 privdata->node = *nodep;
166 return (0);
167}
168
169/*
170 * Add a hook
171 */
172static int
173ngt_newhook(node_p node, hook_p hook, const char *name)
174{
175 const sc_p sc = node->private;
176
177 if (strcmp(name, NG_TEE_HOOK_RIGHT) == 0) {
178 sc->right.hook = hook;
179 bzero(&sc->right.stats, sizeof(sc->right.stats));
180 hook->private = &sc->right;
181 } else if (strcmp(name, NG_TEE_HOOK_LEFT) == 0) {
182 sc->left.hook = hook;
183 bzero(&sc->left.stats, sizeof(sc->left.stats));
184 hook->private = &sc->left;
185 } else if (strcmp(name, NG_TEE_HOOK_RIGHT2LEFT) == 0) {
186 sc->right2left.hook = hook;
187 bzero(&sc->right2left.stats, sizeof(sc->right2left.stats));
188 hook->private = &sc->right2left;
189 } else if (strcmp(name, NG_TEE_HOOK_LEFT2RIGHT) == 0) {
190 sc->left2right.hook = hook;
191 bzero(&sc->left2right.stats, sizeof(sc->left2right.stats));
192 hook->private = &sc->left2right;
193 } else
194 return (EINVAL);
195 return (0);
196}
197
198/*
199 * Receive a control message
200 */
201static int
202ngt_rcvmsg(node_p node, struct ng_mesg *msg, const char *retaddr,
203 struct ng_mesg **rptr, hook_p lasthook)
204{
205 const sc_p sc = node->private;
206 struct ng_mesg *resp = NULL;
207 int error = 0;
208
209 switch (msg->header.typecookie) {
210 case NGM_TEE_COOKIE:
211 switch (msg->header.cmd) {
212 case NGM_TEE_GET_STATS:
213 case NGM_TEE_CLR_STATS:
214 case NGM_TEE_GETCLR_STATS:
215 {
216 struct ng_tee_stats *stats;
217
218 if (msg->header.cmd != NGM_TEE_CLR_STATS) {
219 NG_MKRESPONSE(resp, msg,
220 sizeof(*stats), M_NOWAIT);
221 if (resp == NULL) {
222 error = ENOMEM;
223 goto done;
224 }
225 stats = (struct ng_tee_stats *)resp->data;
226 bcopy(&sc->right.stats, &stats->right,
227 sizeof(stats->right));
228 bcopy(&sc->left.stats, &stats->left,
229 sizeof(stats->left));
230 bcopy(&sc->right2left.stats, &stats->right2left,
231 sizeof(stats->right2left));
232 bcopy(&sc->left2right.stats, &stats->left2right,
233 sizeof(stats->left2right));
234 }
235 if (msg->header.cmd != NGM_TEE_GET_STATS) {
236 bzero(&sc->right.stats,
237 sizeof(sc->right.stats));
238 bzero(&sc->left.stats,
239 sizeof(sc->left.stats));
240 bzero(&sc->right2left.stats,
241 sizeof(sc->right2left.stats));
242 bzero(&sc->left2right.stats,
243 sizeof(sc->left2right.stats));
244 }
245 break;
246 }
247 default:
248 error = EINVAL;
249 break;
250 }
251 break;
252 default:
253 error = EINVAL;
254 break;
255 }
256 if (rptr)
257 *rptr = resp;
258 else if (resp)
259 FREE(resp, M_NETGRAPH);
260
261done:
262 FREE(msg, M_NETGRAPH);
263 return (error);
264}
265
266/*
267 * Receive data on a hook
268 *
269 * If data comes in the right link send a copy out right2left, and then
270 * send the original onwards out through the left link.
271 * Do the opposite for data coming in from the left link.
272 * Data coming in right2left or left2right is forwarded
273 * on through the appropriate destination hook as if it had come
274 * from the other side.
275 */
276static int
277ngt_rcvdata(hook_p hook, struct mbuf *m, meta_p meta,
278 struct mbuf **ret_m, meta_p *ret_meta)
279{
280 const sc_p sc = hook->node->private;
281 struct hookinfo *const hinfo = (struct hookinfo *) hook->private;
282 struct hookinfo *dest;
283 struct hookinfo *dup;
284 int error = 0;
285
286 /* Which hook? */
287 if (hinfo == &sc->left) {
288 dup = &sc->left2right;
289 dest = &sc->right;
290 } else if (hinfo == &sc->right) {
291 dup = &sc->right2left;
292 dest = &sc->left;
293 } else if (hinfo == &sc->right2left) {
294 dup = NULL;
295 dest = &sc->left;
296 } else if (hinfo == &sc->left2right) {
297 dup = NULL;
298 dest = &sc->right;
299 } else
300 panic("%s: no hook!", __FUNCTION__);
301
302 /* Update stats on incoming hook */
303 hinfo->stats.inOctets += m->m_pkthdr.len;
304 hinfo->stats.inFrames++;
305
306 /* Duplicate packet and meta info if requried */
307 if (dup != NULL) {
308 struct mbuf *m2;
309 meta_p meta2;
310
311 /* Copy packet */
312 m2 = m_dup(m, M_NOWAIT);
313 if (m2 == NULL) {
314 NG_FREE_DATA(m, meta);
315 return (ENOBUFS);
316 }
317
318 /* Copy meta info */
319 if (meta != NULL) {
320 MALLOC(meta2, meta_p,
321 meta->used_len, M_NETGRAPH, M_NOWAIT);
322 if (meta2 == NULL) {
323 m_freem(m2);
324 NG_FREE_DATA(m, meta);
325 return (ENOMEM);
326 }
327 bcopy(meta, meta2, meta->used_len);
328 meta2->allocated_len = meta->used_len;
329 } else
330 meta2 = NULL;
331
332 /* Deliver duplicate */
333 dup->stats.outOctets += m->m_pkthdr.len;
334 dup->stats.outFrames++;
335 NG_SEND_DATA(error, dup->hook, m2, meta2);
336 }
337
338 /* Deliver frame out destination hook */
339 dest->stats.outOctets += m->m_pkthdr.len;
340 dest->stats.outFrames++;
341 NG_SEND_DATA(error, dest->hook, m, meta);
342 return (0);
343}
344
345/*
346 * Shutdown processing
347 *
348 * This is tricky. If we have both a left and right hook, then we
349 * probably want to extricate ourselves and leave the two peers
350 * still linked to each other. Otherwise we should just shut down as
351 * a normal node would.
352 *
353 * To keep the scope of info correct the routine to "extract" a node
354 * from two links is in ng_base.c.
355 */
356static int
357ngt_rmnode(node_p node)
358{
359 const sc_p privdata = node->private;
360
361 node->flags |= NG_INVALID;
362 if (privdata->left.hook && privdata->right.hook)
363 ng_bypass(privdata->left.hook, privdata->right.hook);
364 ng_cutlinks(node);
365 ng_unname(node);
366 node->private = NULL;
367 ng_unref(privdata->node);
368 FREE(privdata, M_NETGRAPH);
369 return (0);
370}
371
372/*
373 * Hook disconnection
374 */
375static int
376ngt_disconnect(hook_p hook)
377{
378 struct hookinfo *const hinfo = (struct hookinfo *) hook->private;
379
380 KASSERT(hinfo != NULL, ("%s: null info", __FUNCTION__));
381 hinfo->hook = NULL;
382 if (hook->node->numhooks == 0)
383 ng_rmnode(hook->node);
384 return (0);
385}
386