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 * $FreeBSD$ 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 /* Per hook info */ 64 struct hookinfo { 65 hook_p hook; 66 struct ng_tee_hookstat stats; 67 }; 68 69 /* Per node info */ 70 struct privdata { 71 node_p node; 72 struct hookinfo left; 73 struct hookinfo right; 74 struct hookinfo left2right; 75 struct hookinfo right2left; 76 }; 77 typedef struct privdata *sc_p; 78 79 /* Netgraph methods */ 80 static ng_constructor_t ngt_constructor; 81 static ng_rcvmsg_t ngt_rcvmsg; 82 static ng_close_t ngt_close; 83 static ng_shutdown_t ngt_shutdown; 84 static ng_newhook_t ngt_newhook; 85 static ng_rcvdata_t ngt_rcvdata; 86 static ng_disconnect_t ngt_disconnect; 87 88 /* Parse type for struct ng_tee_hookstat */ 89 static const struct ng_parse_struct_field ng_tee_hookstat_type_fields[] 90 = NG_TEE_HOOKSTAT_INFO; 91 static const struct ng_parse_type ng_tee_hookstat_type = { 92 &ng_parse_struct_type, 93 &ng_tee_hookstat_type_fields 94 }; 95 96 /* Parse type for struct ng_tee_stats */ 97 static const struct ng_parse_struct_field ng_tee_stats_type_fields[] 98 = NG_TEE_STATS_INFO(&ng_tee_hookstat_type); 99 static const struct ng_parse_type ng_tee_stats_type = { 100 &ng_parse_struct_type, 101 &ng_tee_stats_type_fields 102 }; 103 104 /* List of commands and how to convert arguments to/from ASCII */ 105 static const struct ng_cmdlist ng_tee_cmds[] = { 106 { 107 NGM_TEE_COOKIE, 108 NGM_TEE_GET_STATS, 109 "getstats", 110 NULL, 111 &ng_tee_stats_type 112 }, 113 { 114 NGM_TEE_COOKIE, 115 NGM_TEE_CLR_STATS, 116 "clrstats", 117 NULL, 118 NULL 119 }, 120 { 121 NGM_TEE_COOKIE, 122 NGM_TEE_GETCLR_STATS, 123 "getclrstats", 124 NULL, 125 &ng_tee_stats_type 126 }, 127 { 0 } 128 }; 129 130 /* Netgraph type descriptor */ 131 static struct ng_type ng_tee_typestruct = { 132 .version = NG_ABI_VERSION, 133 .name = NG_TEE_NODE_TYPE, 134 .constructor = ngt_constructor, 135 .rcvmsg = ngt_rcvmsg, 136 .close = ngt_close, 137 .shutdown = ngt_shutdown, 138 .newhook = ngt_newhook, 139 .rcvdata = ngt_rcvdata, 140 .disconnect = ngt_disconnect, 141 .cmdlist = ng_tee_cmds, 142 }; 143 NETGRAPH_INIT(tee, &ng_tee_typestruct); 144 145 /* 146 * Node constructor 147 */ 148 static int 149 ngt_constructor(node_p node) 150 { 151 sc_p privdata; 152 153 MALLOC(privdata, sc_p, sizeof(*privdata), M_NETGRAPH, M_NOWAIT|M_ZERO); 154 if (privdata == NULL) 155 return (ENOMEM); 156 157 NG_NODE_SET_PRIVATE(node, privdata); 158 privdata->node = node; 159 return (0); 160 } 161 162 /* 163 * Add a hook 164 */ 165 static int 166 ngt_newhook(node_p node, hook_p hook, const char *name) 167 { 168 const sc_p sc = NG_NODE_PRIVATE(node); 169 170 if (strcmp(name, NG_TEE_HOOK_RIGHT) == 0) { 171 sc->right.hook = hook; 172 bzero(&sc->right.stats, sizeof(sc->right.stats)); 173 NG_HOOK_SET_PRIVATE(hook, &sc->right); 174 } else if (strcmp(name, NG_TEE_HOOK_LEFT) == 0) { 175 sc->left.hook = hook; 176 bzero(&sc->left.stats, sizeof(sc->left.stats)); 177 NG_HOOK_SET_PRIVATE(hook, &sc->left); 178 } else if (strcmp(name, NG_TEE_HOOK_RIGHT2LEFT) == 0) { 179 sc->right2left.hook = hook; 180 bzero(&sc->right2left.stats, sizeof(sc->right2left.stats)); 181 NG_HOOK_SET_PRIVATE(hook, &sc->right2left); 182 } else if (strcmp(name, NG_TEE_HOOK_LEFT2RIGHT) == 0) { 183 sc->left2right.hook = hook; 184 bzero(&sc->left2right.stats, sizeof(sc->left2right.stats)); 185 NG_HOOK_SET_PRIVATE(hook, &sc->left2right); 186 } else 187 return (EINVAL); 188 return (0); 189 } 190 191 /* 192 * Receive a control message 193 */ 194 static int 195 ngt_rcvmsg(node_p node, item_p item, hook_p lasthook) 196 { 197 const sc_p sc = NG_NODE_PRIVATE(node); 198 struct ng_mesg *resp = NULL; 199 int error = 0; 200 struct ng_mesg *msg; 201 202 NGI_GET_MSG(item, msg); 203 switch (msg->header.typecookie) { 204 case NGM_TEE_COOKIE: 205 switch (msg->header.cmd) { 206 case NGM_TEE_GET_STATS: 207 case NGM_TEE_CLR_STATS: 208 case NGM_TEE_GETCLR_STATS: 209 { 210 struct ng_tee_stats *stats; 211 212 if (msg->header.cmd != NGM_TEE_CLR_STATS) { 213 NG_MKRESPONSE(resp, msg, 214 sizeof(*stats), M_NOWAIT); 215 if (resp == NULL) { 216 error = ENOMEM; 217 goto done; 218 } 219 stats = (struct ng_tee_stats *)resp->data; 220 bcopy(&sc->right.stats, &stats->right, 221 sizeof(stats->right)); 222 bcopy(&sc->left.stats, &stats->left, 223 sizeof(stats->left)); 224 bcopy(&sc->right2left.stats, &stats->right2left, 225 sizeof(stats->right2left)); 226 bcopy(&sc->left2right.stats, &stats->left2right, 227 sizeof(stats->left2right)); 228 } 229 if (msg->header.cmd != NGM_TEE_GET_STATS) { 230 bzero(&sc->right.stats, 231 sizeof(sc->right.stats)); 232 bzero(&sc->left.stats, 233 sizeof(sc->left.stats)); 234 bzero(&sc->right2left.stats, 235 sizeof(sc->right2left.stats)); 236 bzero(&sc->left2right.stats, 237 sizeof(sc->left2right.stats)); 238 } 239 break; 240 } 241 default: 242 error = EINVAL; 243 break; 244 } 245 break; 246 case NGM_FLOW_COOKIE: 247 if (lasthook) { 248 if (lasthook == sc->left.hook) { 249 if (sc->right.hook) { 250 NGI_MSG(item) = msg; 251 NG_FWD_ITEM_HOOK(error, item, 252 sc->right.hook); 253 return (error); 254 } 255 } else { 256 if (sc->left.hook) { 257 NGI_MSG(item) = msg; 258 NG_FWD_ITEM_HOOK(error, item, 259 sc->left.hook); 260 return (error); 261 } 262 } 263 } 264 break; 265 default: 266 error = EINVAL; 267 break; 268 } 269 done: 270 NG_RESPOND_MSG(error, node, item, resp); 271 NG_FREE_MSG(msg); 272 return (error); 273 } 274 275 /* 276 * Receive data on a hook 277 * 278 * If data comes in the right link send a copy out right2left, and then 279 * send the original onwards out through the left link. 280 * Do the opposite for data coming in from the left link. 281 * Data coming in right2left or left2right is forwarded 282 * on through the appropriate destination hook as if it had come 283 * from the other side. 284 */ 285 static int 286 ngt_rcvdata(hook_p hook, item_p item) 287 { 288 const sc_p sc = NG_NODE_PRIVATE(NG_HOOK_NODE(hook)); 289 struct hookinfo *const hinfo = NG_HOOK_PRIVATE(hook); 290 struct hookinfo *dest; 291 struct hookinfo *dup; 292 int error = 0; 293 struct mbuf *m; 294 295 m = NGI_M(item); 296 /* Which hook? */ 297 if (hinfo == &sc->left) { 298 dup = &sc->left2right; 299 dest = &sc->right; 300 } else if (hinfo == &sc->right) { 301 dup = &sc->right2left; 302 dest = &sc->left; 303 } else if (hinfo == &sc->right2left) { 304 dup = NULL; 305 dest = &sc->right; 306 } else if (hinfo == &sc->left2right) { 307 dup = NULL; 308 dest = &sc->left; 309 } else { 310 panic("%s: no hook!", __func__); 311 #ifdef RESTARTABLE_PANICS 312 return(EINVAL); 313 #endif 314 } 315 316 /* Update stats on incoming hook */ 317 hinfo->stats.inOctets += m->m_pkthdr.len; 318 hinfo->stats.inFrames++; 319 320 /* 321 * Don't make a copy if only the dup hook exists. 322 */ 323 if ((dup && dup->hook) && (dest->hook == NULL)) { 324 dest = dup; 325 dup = NULL; 326 } 327 328 /* Duplicate packet if requried */ 329 if (dup && dup->hook) { 330 struct mbuf *m2; 331 332 /* Copy packet (failure will not stop the original)*/ 333 m2 = m_dup(m, M_DONTWAIT); 334 if (m2) { 335 /* Deliver duplicate */ 336 dup->stats.outOctets += m->m_pkthdr.len; 337 dup->stats.outFrames++; 338 NG_SEND_DATA_ONLY(error, dup->hook, m2); 339 } 340 } 341 /* Deliver frame out destination hook */ 342 if (dest->hook) { 343 dest->stats.outOctets += m->m_pkthdr.len; 344 dest->stats.outFrames++; 345 NG_FWD_ITEM_HOOK(error, item, dest->hook); 346 } else 347 NG_FREE_ITEM(item); 348 return (error); 349 } 350 351 /* 352 * We are going to be shut down soon 353 * 354 * If we have both a left and right hook, then we probably want to extricate 355 * ourselves and leave the two peers still linked to each other. Otherwise we 356 * should just shut down as a normal node would. 357 */ 358 static int 359 ngt_close(node_p node) 360 { 361 const sc_p privdata = NG_NODE_PRIVATE(node); 362 363 if (privdata->left.hook && privdata->right.hook) 364 ng_bypass(privdata->left.hook, privdata->right.hook); 365 366 return (0); 367 } 368 369 /* 370 * Shutdown processing 371 */ 372 static int 373 ngt_shutdown(node_p node) 374 { 375 const sc_p privdata = NG_NODE_PRIVATE(node); 376 377 NG_NODE_SET_PRIVATE(node, NULL); 378 NG_NODE_UNREF(privdata->node); 379 FREE(privdata, M_NETGRAPH); 380 return (0); 381 } 382 383 /* 384 * Hook disconnection 385 */ 386 static int 387 ngt_disconnect(hook_p hook) 388 { 389 struct hookinfo *const hinfo = NG_HOOK_PRIVATE(hook); 390 391 KASSERT(hinfo != NULL, ("%s: null info", __func__)); 392 hinfo->hook = NULL; 393 if ((NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0) 394 && (NG_NODE_IS_VALID(NG_HOOK_NODE(hook)))) 395 ng_rmnode_self(NG_HOOK_NODE(hook)); 396 return (0); 397 } 398 399