1
2 /*
3 * ng_tee.c
4 */
5
6 /*-
7 * Copyright (c) 1996-1999 Whistle Communications, Inc.
8 * All rights reserved.
9 *
10 * Subject to the following obligations and disclaimer of warranty, use and
11 * redistribution of this software, in source or object code forms, with or
12 * without modifications are expressly permitted by Whistle Communications;
13 * provided, however, that:
14 * 1. Any and all reproductions of the source or object code must include the
15 * copyright notice above and the following disclaimer of warranties; and
16 * 2. No rights are granted, in any manner or form, to use Whistle
17 * Communications, Inc. trademarks, including the mark "WHISTLE
18 * COMMUNICATIONS" on advertising, endorsements, or otherwise except as
19 * such appears in the above copyright notice or in the software.
20 *
21 * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
22 * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
23 * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
24 * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
25 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
26 * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
27 * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
28 * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
29 * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
30 * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
31 * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
32 * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
33 * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
34 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
35 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
36 * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
37 * OF SUCH DAMAGE.
38 *
39 * Author: Julian Elischer <julian@freebsd.org>
40 *
41 * $FreeBSD: src/sys/netgraph/ng_tee.c,v 1.35 2008/02/24 10:13:32 mav Exp $
42 * $Whistle: ng_tee.c,v 1.18 1999/11/01 09:24:52 julian Exp $
43 */
44
45 /*
46 * This node is like the tee(1) command and is useful for ``snooping.''
47 * It has 4 hooks: left, right, left2right, and right2left. Data
48 * entering from the right is passed to the left and duplicated on
49 * right2left, and data entering from the left is passed to the right
50 * and duplicated on left2right. Data entering from left2right is
51 * sent to left, and data from right2left to right.
52 */
53
54 #include <sys/param.h>
55 #include <sys/systm.h>
56 #include <sys/errno.h>
57 #include <sys/kernel.h>
58 #include <sys/malloc.h>
59 #include <sys/mbuf.h>
60 #include <netgraph7/ng_message.h>
61 #include <netgraph7/netgraph.h>
62 #include <netgraph7/ng_parse.h>
63 #include "ng_tee.h"
64
65 /* Per hook info */
66 struct hookinfo {
67 hook_p hook;
68 struct hookinfo *dest, *dup;
69 struct ng_tee_hookstat stats;
70 };
71 typedef struct hookinfo *hi_p;
72
73 /* Per node info */
74 struct privdata {
75 struct hookinfo left;
76 struct hookinfo right;
77 struct hookinfo left2right;
78 struct hookinfo right2left;
79 };
80 typedef struct privdata *sc_p;
81
82 /* Netgraph methods */
83 static ng_constructor_t ng_tee_constructor;
84 static ng_rcvmsg_t ng_tee_rcvmsg;
85 static ng_close_t ng_tee_close;
86 static ng_shutdown_t ng_tee_shutdown;
87 static ng_newhook_t ng_tee_newhook;
88 static ng_rcvdata_t ng_tee_rcvdata;
89 static ng_disconnect_t ng_tee_disconnect;
90
91 /* Parse type for struct ng_tee_hookstat */
92 static const struct ng_parse_struct_field ng_tee_hookstat_type_fields[]
93 = NG_TEE_HOOKSTAT_INFO;
94 static const struct ng_parse_type ng_tee_hookstat_type = {
95 &ng_parse_struct_type,
96 &ng_tee_hookstat_type_fields
97 };
98
99 /* Parse type for struct ng_tee_stats */
100 static const struct ng_parse_struct_field ng_tee_stats_type_fields[]
101 = NG_TEE_STATS_INFO(&ng_tee_hookstat_type);
102 static const struct ng_parse_type ng_tee_stats_type = {
103 &ng_parse_struct_type,
104 &ng_tee_stats_type_fields
105 };
106
107 /* List of commands and how to convert arguments to/from ASCII */
108 static const struct ng_cmdlist ng_tee_cmds[] = {
109 {
110 NGM_TEE_COOKIE,
111 NGM_TEE_GET_STATS,
112 "getstats",
113 NULL,
114 &ng_tee_stats_type
115 },
116 {
117 NGM_TEE_COOKIE,
118 NGM_TEE_CLR_STATS,
119 "clrstats",
120 NULL,
121 NULL
122 },
123 {
124 NGM_TEE_COOKIE,
125 NGM_TEE_GETCLR_STATS,
126 "getclrstats",
127 NULL,
128 &ng_tee_stats_type
129 },
130 { 0 }
131 };
132
133 /* Netgraph type descriptor */
134 static struct ng_type ng_tee_typestruct = {
135 .version = NG_ABI_VERSION,
136 .name = NG_TEE_NODE_TYPE,
137 .constructor = ng_tee_constructor,
138 .rcvmsg = ng_tee_rcvmsg,
139 .close = ng_tee_close,
140 .shutdown = ng_tee_shutdown,
141 .newhook = ng_tee_newhook,
142 .rcvdata = ng_tee_rcvdata,
143 .disconnect = ng_tee_disconnect,
144 .cmdlist = ng_tee_cmds,
145 };
146 NETGRAPH_INIT(tee, &ng_tee_typestruct);
147
148 /*
149 * Node constructor
150 */
151 static int
ng_tee_constructor(node_p node)152 ng_tee_constructor(node_p node)
153 {
154 sc_p privdata;
155
156 privdata = kmalloc(sizeof(*privdata), M_NETGRAPH,
157 M_WAITOK | M_NULLOK | M_ZERO);
158 if (privdata == NULL)
159 return (ENOMEM);
160
161 NG_NODE_SET_PRIVATE(node, privdata);
162 return (0);
163 }
164
165 /*
166 * Add a hook
167 */
168 static int
ng_tee_newhook(node_p node,hook_p hook,const char * name)169 ng_tee_newhook(node_p node, hook_p hook, const char *name)
170 {
171 sc_p privdata = NG_NODE_PRIVATE(node);
172 hi_p hinfo;
173
174 /* Precalculate internal pathes. */
175 if (strcmp(name, NG_TEE_HOOK_RIGHT) == 0) {
176 hinfo = &privdata->right;
177 if (privdata->left.dest)
178 privdata->left.dup = privdata->left.dest;
179 privdata->left.dest = hinfo;
180 privdata->right2left.dest = hinfo;
181 } else if (strcmp(name, NG_TEE_HOOK_LEFT) == 0) {
182 hinfo = &privdata->left;
183 if (privdata->right.dest)
184 privdata->right.dup = privdata->right.dest;
185 privdata->right.dest = hinfo;
186 privdata->left2right.dest = hinfo;
187 } else if (strcmp(name, NG_TEE_HOOK_RIGHT2LEFT) == 0) {
188 hinfo = &privdata->right2left;
189 if (privdata->right.dest)
190 privdata->right.dup = hinfo;
191 else
192 privdata->right.dest = hinfo;
193 } else if (strcmp(name, NG_TEE_HOOK_LEFT2RIGHT) == 0) {
194 hinfo = &privdata->left2right;
195 if (privdata->left.dest)
196 privdata->left.dup = hinfo;
197 else
198 privdata->left.dest = hinfo;
199 } else
200 return (EINVAL);
201 hinfo->hook = hook;
202 bzero(&hinfo->stats, sizeof(hinfo->stats));
203 NG_HOOK_SET_PRIVATE(hook, hinfo);
204 return (0);
205 }
206
207 /*
208 * Receive a control message
209 */
210 static int
ng_tee_rcvmsg(node_p node,item_p item,hook_p lasthook)211 ng_tee_rcvmsg(node_p node, item_p item, hook_p lasthook)
212 {
213 const sc_p sc = NG_NODE_PRIVATE(node);
214 struct ng_mesg *resp = NULL;
215 int error = 0;
216 struct ng_mesg *msg;
217
218 NGI_GET_MSG(item, msg);
219 switch (msg->header.typecookie) {
220 case NGM_TEE_COOKIE:
221 switch (msg->header.cmd) {
222 case NGM_TEE_GET_STATS:
223 case NGM_TEE_CLR_STATS:
224 case NGM_TEE_GETCLR_STATS:
225 {
226 struct ng_tee_stats *stats;
227
228 if (msg->header.cmd != NGM_TEE_CLR_STATS) {
229 NG_MKRESPONSE(resp, msg,
230 sizeof(*stats), M_WAITOK | M_NULLOK);
231 if (resp == NULL) {
232 error = ENOMEM;
233 goto done;
234 }
235 stats = (struct ng_tee_stats *)resp->data;
236 bcopy(&sc->right.stats, &stats->right,
237 sizeof(stats->right));
238 bcopy(&sc->left.stats, &stats->left,
239 sizeof(stats->left));
240 bcopy(&sc->right2left.stats, &stats->right2left,
241 sizeof(stats->right2left));
242 bcopy(&sc->left2right.stats, &stats->left2right,
243 sizeof(stats->left2right));
244 }
245 if (msg->header.cmd != NGM_TEE_GET_STATS) {
246 bzero(&sc->right.stats,
247 sizeof(sc->right.stats));
248 bzero(&sc->left.stats,
249 sizeof(sc->left.stats));
250 bzero(&sc->right2left.stats,
251 sizeof(sc->right2left.stats));
252 bzero(&sc->left2right.stats,
253 sizeof(sc->left2right.stats));
254 }
255 break;
256 }
257 default:
258 error = EINVAL;
259 break;
260 }
261 break;
262 case NGM_FLOW_COOKIE:
263 if (lasthook == sc->left.hook || lasthook == sc->right.hook) {
264 hi_p const hinfo = NG_HOOK_PRIVATE(lasthook);
265 if (hinfo && hinfo->dest) {
266 NGI_MSG(item) = msg;
267 NG_FWD_ITEM_HOOK(error, item, hinfo->dest->hook);
268 return (error);
269 }
270 }
271 break;
272 default:
273 error = EINVAL;
274 break;
275 }
276 done:
277 NG_RESPOND_MSG(error, node, item, resp);
278 NG_FREE_MSG(msg);
279 return (error);
280 }
281
282 /*
283 * Receive data on a hook
284 *
285 * If data comes in the right link send a copy out right2left, and then
286 * send the original onwards out through the left link.
287 * Do the opposite for data coming in from the left link.
288 * Data coming in right2left or left2right is forwarded
289 * on through the appropriate destination hook as if it had come
290 * from the other side.
291 */
292 static int
ng_tee_rcvdata(hook_p hook,item_p item)293 ng_tee_rcvdata(hook_p hook, item_p item)
294 {
295 const hi_p hinfo = NG_HOOK_PRIVATE(hook);
296 hi_p h;
297 int error = 0;
298 struct mbuf *m;
299
300 m = NGI_M(item);
301
302 /* Update stats on incoming hook */
303 hinfo->stats.inOctets += m->m_pkthdr.len;
304 hinfo->stats.inFrames++;
305
306 /* Duplicate packet if requried */
307 if (hinfo->dup) {
308 struct mbuf *m2;
309
310 /* Copy packet (failure will not stop the original)*/
311 m2 = m_dup(m, M_NOWAIT);
312 if (m2) {
313 /* Deliver duplicate */
314 h = hinfo->dup;
315 NG_SEND_DATA_ONLY(error, h->hook, m2);
316 if (error == 0) {
317 h->stats.outOctets += m->m_pkthdr.len;
318 h->stats.outFrames++;
319 }
320 }
321 }
322 /* Deliver frame out destination hook */
323 if (hinfo->dest) {
324 h = hinfo->dest;
325 h->stats.outOctets += m->m_pkthdr.len;
326 h->stats.outFrames++;
327 NG_FWD_ITEM_HOOK(error, item, h->hook);
328 } else
329 NG_FREE_ITEM(item);
330 return (error);
331 }
332
333 /*
334 * We are going to be shut down soon
335 *
336 * If we have both a left and right hook, then we probably want to extricate
337 * ourselves and leave the two peers still linked to each other. Otherwise we
338 * should just shut down as a normal node would.
339 */
340 static int
ng_tee_close(node_p node)341 ng_tee_close(node_p node)
342 {
343 const sc_p privdata = NG_NODE_PRIVATE(node);
344
345 if (privdata->left.hook && privdata->right.hook)
346 ng_bypass(privdata->left.hook, privdata->right.hook);
347
348 return (0);
349 }
350
351 /*
352 * Shutdown processing
353 */
354 static int
ng_tee_shutdown(node_p node)355 ng_tee_shutdown(node_p node)
356 {
357 const sc_p privdata = NG_NODE_PRIVATE(node);
358
359 NG_NODE_SET_PRIVATE(node, NULL);
360 kfree(privdata, M_NETGRAPH);
361 NG_NODE_UNREF(node);
362 return (0);
363 }
364
365 /*
366 * Hook disconnection
367 */
368 static int
ng_tee_disconnect(hook_p hook)369 ng_tee_disconnect(hook_p hook)
370 {
371 sc_p sc = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
372 hi_p const hinfo = NG_HOOK_PRIVATE(hook);
373
374 KASSERT(hinfo != NULL, ("%s: null info", __func__));
375 hinfo->hook = NULL;
376
377 /* Recalculate internal pathes. */
378 if (sc->left.dest == hinfo) {
379 sc->left.dest = sc->left.dup;
380 sc->left.dup = NULL;
381 } else if (sc->left.dup == hinfo)
382 sc->left.dup = NULL;
383 if (sc->right.dest == hinfo) {
384 sc->right.dest = sc->right.dup;
385 sc->right.dup = NULL;
386 } else if (sc->right.dup == hinfo)
387 sc->right.dup = NULL;
388 if (sc->left2right.dest == hinfo)
389 sc->left2right.dest = NULL;
390 if (sc->right2left.dest == hinfo)
391 sc->right2left.dest = NULL;
392
393 /* Die when last hook disconnected. */
394 if ((NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0) &&
395 NG_NODE_IS_VALID(NG_HOOK_NODE(hook)))
396 ng_rmnode_self(NG_HOOK_NODE(hook));
397 return (0);
398 }
399