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 * $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 left, and data from right2left to right.
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 #ifdef NG_SEPARATE_MALLOC
64 static MALLOC_DEFINE(M_NETGRAPH_TEE, "netgraph_tee", "netgraph tee node");
65 #else
66 #define M_NETGRAPH_TEE M_NETGRAPH
67 #endif
68
69 /* Per hook info */
70 struct hookinfo {
71 hook_p hook;
72 struct hookinfo *dest, *dup;
73 struct ng_tee_hookstat stats;
74 };
75 typedef struct hookinfo *hi_p;
76
77 /* Per node info */
78 struct privdata {
79 struct hookinfo left;
80 struct hookinfo right;
81 struct hookinfo left2right;
82 struct hookinfo right2left;
83 };
84 typedef struct privdata *sc_p;
85
86 /* Netgraph methods */
87 static ng_constructor_t ng_tee_constructor;
88 static ng_rcvmsg_t ng_tee_rcvmsg;
89 static ng_close_t ng_tee_close;
90 static ng_shutdown_t ng_tee_shutdown;
91 static ng_newhook_t ng_tee_newhook;
92 static ng_rcvdata_t ng_tee_rcvdata;
93 static ng_disconnect_t ng_tee_disconnect;
94
95 /* Parse type for struct ng_tee_hookstat */
96 static const struct ng_parse_struct_field ng_tee_hookstat_type_fields[]
97 = NG_TEE_HOOKSTAT_INFO;
98 static const struct ng_parse_type ng_tee_hookstat_type = {
99 &ng_parse_struct_type,
100 &ng_tee_hookstat_type_fields
101 };
102
103 /* Parse type for struct ng_tee_stats */
104 static const struct ng_parse_struct_field ng_tee_stats_type_fields[]
105 = NG_TEE_STATS_INFO(&ng_tee_hookstat_type);
106 static const struct ng_parse_type ng_tee_stats_type = {
107 &ng_parse_struct_type,
108 &ng_tee_stats_type_fields
109 };
110
111 /* List of commands and how to convert arguments to/from ASCII */
112 static const struct ng_cmdlist ng_tee_cmds[] = {
113 {
114 NGM_TEE_COOKIE,
115 NGM_TEE_GET_STATS,
116 "getstats",
117 NULL,
118 &ng_tee_stats_type
119 },
120 {
121 NGM_TEE_COOKIE,
122 NGM_TEE_CLR_STATS,
123 "clrstats",
124 NULL,
125 NULL
126 },
127 {
128 NGM_TEE_COOKIE,
129 NGM_TEE_GETCLR_STATS,
130 "getclrstats",
131 NULL,
132 &ng_tee_stats_type
133 },
134 { 0 }
135 };
136
137 /* Netgraph type descriptor */
138 static struct ng_type ng_tee_typestruct = {
139 .version = NG_ABI_VERSION,
140 .name = NG_TEE_NODE_TYPE,
141 .constructor = ng_tee_constructor,
142 .rcvmsg = ng_tee_rcvmsg,
143 .close = ng_tee_close,
144 .shutdown = ng_tee_shutdown,
145 .newhook = ng_tee_newhook,
146 .rcvdata = ng_tee_rcvdata,
147 .disconnect = ng_tee_disconnect,
148 .cmdlist = ng_tee_cmds,
149 };
150 NETGRAPH_INIT(tee, &ng_tee_typestruct);
151
152 /*
153 * Node constructor
154 */
155 static int
ng_tee_constructor(node_p node)156 ng_tee_constructor(node_p node)
157 {
158 sc_p privdata;
159
160 privdata = malloc(sizeof(*privdata), M_NETGRAPH_TEE, M_WAITOK | M_ZERO);
161
162 NG_NODE_SET_PRIVATE(node, privdata);
163 return (0);
164 }
165
166 /*
167 * Add a hook
168 */
169 static int
ng_tee_newhook(node_p node,hook_p hook,const char * name)170 ng_tee_newhook(node_p node, hook_p hook, const char *name)
171 {
172 sc_p privdata = NG_NODE_PRIVATE(node);
173 hi_p hinfo;
174
175 /* Precalculate internal paths. */
176 if (strcmp(name, NG_TEE_HOOK_RIGHT) == 0) {
177 hinfo = &privdata->right;
178 if (privdata->left.dest)
179 privdata->left.dup = privdata->left.dest;
180 privdata->left.dest = hinfo;
181 privdata->right2left.dest = hinfo;
182 } else if (strcmp(name, NG_TEE_HOOK_LEFT) == 0) {
183 hinfo = &privdata->left;
184 if (privdata->right.dest)
185 privdata->right.dup = privdata->right.dest;
186 privdata->right.dest = hinfo;
187 privdata->left2right.dest = hinfo;
188 } else if (strcmp(name, NG_TEE_HOOK_RIGHT2LEFT) == 0) {
189 hinfo = &privdata->right2left;
190 if (privdata->right.dest)
191 privdata->right.dup = hinfo;
192 else
193 privdata->right.dest = hinfo;
194 } else if (strcmp(name, NG_TEE_HOOK_LEFT2RIGHT) == 0) {
195 hinfo = &privdata->left2right;
196 if (privdata->left.dest)
197 privdata->left.dup = hinfo;
198 else
199 privdata->left.dest = hinfo;
200 } else
201 return (EINVAL);
202 hinfo->hook = hook;
203 bzero(&hinfo->stats, sizeof(hinfo->stats));
204 NG_HOOK_SET_PRIVATE(hook, hinfo);
205 return (0);
206 }
207
208 /*
209 * Receive a control message
210 */
211 static int
ng_tee_rcvmsg(node_p node,item_p item,hook_p lasthook)212 ng_tee_rcvmsg(node_p node, item_p item, hook_p lasthook)
213 {
214 const sc_p sc = NG_NODE_PRIVATE(node);
215 struct ng_mesg *resp = NULL;
216 int error = 0;
217 struct ng_mesg *msg;
218
219 NGI_GET_MSG(item, msg);
220 switch (msg->header.typecookie) {
221 case NGM_TEE_COOKIE:
222 switch (msg->header.cmd) {
223 case NGM_TEE_GET_STATS:
224 case NGM_TEE_CLR_STATS:
225 case NGM_TEE_GETCLR_STATS:
226 {
227 struct ng_tee_stats *stats;
228
229 if (msg->header.cmd != NGM_TEE_CLR_STATS) {
230 NG_MKRESPONSE(resp, msg,
231 sizeof(*stats), M_NOWAIT);
232 if (resp == NULL) {
233 error = ENOMEM;
234 goto done;
235 }
236 stats = (struct ng_tee_stats *)resp->data;
237 bcopy(&sc->right.stats, &stats->right,
238 sizeof(stats->right));
239 bcopy(&sc->left.stats, &stats->left,
240 sizeof(stats->left));
241 bcopy(&sc->right2left.stats, &stats->right2left,
242 sizeof(stats->right2left));
243 bcopy(&sc->left2right.stats, &stats->left2right,
244 sizeof(stats->left2right));
245 }
246 if (msg->header.cmd != NGM_TEE_GET_STATS) {
247 bzero(&sc->right.stats,
248 sizeof(sc->right.stats));
249 bzero(&sc->left.stats,
250 sizeof(sc->left.stats));
251 bzero(&sc->right2left.stats,
252 sizeof(sc->right2left.stats));
253 bzero(&sc->left2right.stats,
254 sizeof(sc->left2right.stats));
255 }
256 break;
257 }
258 default:
259 error = EINVAL;
260 break;
261 }
262 break;
263 case NGM_FLOW_COOKIE:
264 if (lasthook == sc->left.hook || lasthook == sc->right.hook) {
265 hi_p const hinfo = NG_HOOK_PRIVATE(lasthook);
266 if (hinfo && hinfo->dest) {
267 NGI_MSG(item) = msg;
268 NG_FWD_ITEM_HOOK(error, item, hinfo->dest->hook);
269 return (error);
270 }
271 }
272 break;
273 default:
274 error = EINVAL;
275 break;
276 }
277 done:
278 NG_RESPOND_MSG(error, node, item, resp);
279 NG_FREE_MSG(msg);
280 return (error);
281 }
282
283 /*
284 * Receive data on a hook
285 *
286 * If data comes in the right link send a copy out right2left, and then
287 * send the original onwards out through the left link.
288 * Do the opposite for data coming in from the left link.
289 * Data coming in right2left or left2right is forwarded
290 * on through the appropriate destination hook as if it had come
291 * from the other side.
292 */
293 static int
ng_tee_rcvdata(hook_p hook,item_p item)294 ng_tee_rcvdata(hook_p hook, item_p item)
295 {
296 const hi_p hinfo = NG_HOOK_PRIVATE(hook);
297 hi_p h;
298 int error = 0;
299 struct mbuf *m;
300
301 m = NGI_M(item);
302
303 /* Update stats on incoming hook */
304 hinfo->stats.inOctets += m->m_pkthdr.len;
305 hinfo->stats.inFrames++;
306
307 /* Duplicate packet if requried */
308 if (hinfo->dup) {
309 struct mbuf *m2;
310
311 /* Copy packet (failure will not stop the original)*/
312 m2 = m_dup(m, M_NOWAIT);
313 if (m2) {
314 /* Deliver duplicate */
315 h = hinfo->dup;
316 NG_SEND_DATA_ONLY(error, h->hook, m2);
317 if (error == 0) {
318 h->stats.outOctets += m->m_pkthdr.len;
319 h->stats.outFrames++;
320 }
321 }
322 }
323 /* Deliver frame out destination hook */
324 if (hinfo->dest) {
325 h = hinfo->dest;
326 h->stats.outOctets += m->m_pkthdr.len;
327 h->stats.outFrames++;
328 NG_FWD_ITEM_HOOK(error, item, h->hook);
329 } else
330 NG_FREE_ITEM(item);
331 return (error);
332 }
333
334 /*
335 * We are going to be shut down soon
336 *
337 * If we have both a left and right hook, then we probably want to extricate
338 * ourselves and leave the two peers still linked to each other. Otherwise we
339 * should just shut down as a normal node would.
340 */
341 static int
ng_tee_close(node_p node)342 ng_tee_close(node_p node)
343 {
344 const sc_p privdata = NG_NODE_PRIVATE(node);
345
346 if (privdata->left.hook && privdata->right.hook)
347 ng_bypass(privdata->left.hook, privdata->right.hook);
348
349 return (0);
350 }
351
352 /*
353 * Shutdown processing
354 */
355 static int
ng_tee_shutdown(node_p node)356 ng_tee_shutdown(node_p node)
357 {
358 const sc_p privdata = NG_NODE_PRIVATE(node);
359
360 NG_NODE_SET_PRIVATE(node, NULL);
361 free(privdata, M_NETGRAPH_TEE);
362 NG_NODE_UNREF(node);
363 return (0);
364 }
365
366 /*
367 * Hook disconnection
368 */
369 static int
ng_tee_disconnect(hook_p hook)370 ng_tee_disconnect(hook_p hook)
371 {
372 sc_p sc = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
373 hi_p const hinfo = NG_HOOK_PRIVATE(hook);
374
375 KASSERT(hinfo != NULL, ("%s: null info", __func__));
376 hinfo->hook = NULL;
377
378 /* Recalculate internal paths. */
379 if (sc->left.dest == hinfo) {
380 sc->left.dest = sc->left.dup;
381 sc->left.dup = NULL;
382 } else if (sc->left.dup == hinfo)
383 sc->left.dup = NULL;
384 if (sc->right.dest == hinfo) {
385 sc->right.dest = sc->right.dup;
386 sc->right.dup = NULL;
387 } else if (sc->right.dup == hinfo)
388 sc->right.dup = NULL;
389 if (sc->left2right.dest == hinfo)
390 sc->left2right.dest = NULL;
391 if (sc->right2left.dest == hinfo)
392 sc->right2left.dest = NULL;
393
394 /* Die when last hook disconnected. */
395 if ((NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0) &&
396 NG_NODE_IS_VALID(NG_HOOK_NODE(hook)))
397 ng_rmnode_self(NG_HOOK_NODE(hook));
398 return (0);
399 }
400