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 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 */ 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_shutdown_t ngt_shutdown; 83 static ng_newhook_t ngt_newhook; 84 static ng_rcvdata_t ngt_rcvdata; 85 static ng_disconnect_t ngt_disconnect; 86 87 /* Parse type for struct ng_tee_hookstat */ 88 static const struct ng_parse_struct_info 89 ng_tee_hookstat_type_info = NG_TEE_HOOKSTAT_INFO; 90 static 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 */ 96 static const struct ng_parse_struct_info 97 ng_tee_stats_type_info = NG_TEE_STATS_INFO(&ng_tee_hookstat_type); 98 static 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 */ 104 static 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 */ 130 static struct ng_type ng_tee_typestruct = { 131 NG_ABI_VERSION, 132 NG_TEE_NODE_TYPE, 133 NULL, 134 ngt_constructor, 135 ngt_rcvmsg, 136 ngt_shutdown, 137 ngt_newhook, 138 NULL, 139 NULL, 140 ngt_rcvdata, 141 ngt_disconnect, 142 ng_tee_cmds 143 }; 144 NETGRAPH_INIT(tee, &ng_tee_typestruct); 145 146 /* 147 * Node constructor 148 */ 149 static int 150 ngt_constructor(node_p node) 151 { 152 sc_p privdata; 153 154 MALLOC(privdata, sc_p, sizeof(*privdata), M_NETGRAPH, M_NOWAIT|M_ZERO); 155 if (privdata == NULL) 156 return (ENOMEM); 157 158 NG_NODE_SET_PRIVATE(node, privdata); 159 privdata->node = node; 160 return (0); 161 } 162 163 /* 164 * Add a hook 165 */ 166 static int 167 ngt_newhook(node_p node, hook_p hook, const char *name) 168 { 169 const sc_p sc = NG_NODE_PRIVATE(node); 170 171 if (strcmp(name, NG_TEE_HOOK_RIGHT) == 0) { 172 sc->right.hook = hook; 173 bzero(&sc->right.stats, sizeof(sc->right.stats)); 174 NG_HOOK_SET_PRIVATE(hook, &sc->right); 175 } else if (strcmp(name, NG_TEE_HOOK_LEFT) == 0) { 176 sc->left.hook = hook; 177 bzero(&sc->left.stats, sizeof(sc->left.stats)); 178 NG_HOOK_SET_PRIVATE(hook, &sc->left); 179 } else if (strcmp(name, NG_TEE_HOOK_RIGHT2LEFT) == 0) { 180 sc->right2left.hook = hook; 181 bzero(&sc->right2left.stats, sizeof(sc->right2left.stats)); 182 NG_HOOK_SET_PRIVATE(hook, &sc->right2left); 183 } else if (strcmp(name, NG_TEE_HOOK_LEFT2RIGHT) == 0) { 184 sc->left2right.hook = hook; 185 bzero(&sc->left2right.stats, sizeof(sc->left2right.stats)); 186 NG_HOOK_SET_PRIVATE(hook, &sc->left2right); 187 } else 188 return (EINVAL); 189 return (0); 190 } 191 192 /* 193 * Receive a control message 194 */ 195 static int 196 ngt_rcvmsg(node_p node, item_p item, hook_p lasthook) 197 { 198 const sc_p sc = NG_NODE_PRIVATE(node); 199 struct ng_mesg *resp = NULL; 200 int error = 0; 201 struct ng_mesg *msg; 202 203 NGI_GET_MSG(item, msg); 204 switch (msg->header.typecookie) { 205 case NGM_TEE_COOKIE: 206 switch (msg->header.cmd) { 207 case NGM_TEE_GET_STATS: 208 case NGM_TEE_CLR_STATS: 209 case NGM_TEE_GETCLR_STATS: 210 { 211 struct ng_tee_stats *stats; 212 213 if (msg->header.cmd != NGM_TEE_CLR_STATS) { 214 NG_MKRESPONSE(resp, msg, 215 sizeof(*stats), M_NOWAIT); 216 if (resp == NULL) { 217 error = ENOMEM; 218 goto done; 219 } 220 stats = (struct ng_tee_stats *)resp->data; 221 bcopy(&sc->right.stats, &stats->right, 222 sizeof(stats->right)); 223 bcopy(&sc->left.stats, &stats->left, 224 sizeof(stats->left)); 225 bcopy(&sc->right2left.stats, &stats->right2left, 226 sizeof(stats->right2left)); 227 bcopy(&sc->left2right.stats, &stats->left2right, 228 sizeof(stats->left2right)); 229 } 230 if (msg->header.cmd != NGM_TEE_GET_STATS) { 231 bzero(&sc->right.stats, 232 sizeof(sc->right.stats)); 233 bzero(&sc->left.stats, 234 sizeof(sc->left.stats)); 235 bzero(&sc->right2left.stats, 236 sizeof(sc->right2left.stats)); 237 bzero(&sc->left2right.stats, 238 sizeof(sc->left2right.stats)); 239 } 240 break; 241 } 242 default: 243 error = EINVAL; 244 break; 245 } 246 break; 247 case NGM_FLOW_COOKIE: 248 if (lasthook) { 249 if (lasthook == sc->left.hook) { 250 if (sc->right.hook) { 251 NGI_MSG(item) = msg; 252 NG_FWD_ITEM_HOOK(error, item, 253 sc->right.hook); 254 return (error); 255 } 256 } else { 257 if (sc->left.hook) { 258 NGI_MSG(item) = msg; 259 NG_FWD_ITEM_HOOK(error, item, 260 sc->left.hook); 261 return (error); 262 } 263 } 264 } 265 break; 266 default: 267 error = EINVAL; 268 break; 269 } 270 done: 271 NG_RESPOND_MSG(error, node, item, resp); 272 NG_FREE_MSG(msg); 273 return (error); 274 } 275 276 /* 277 * Receive data on a hook 278 * 279 * If data comes in the right link send a copy out right2left, and then 280 * send the original onwards out through the left link. 281 * Do the opposite for data coming in from the left link. 282 * Data coming in right2left or left2right is forwarded 283 * on through the appropriate destination hook as if it had come 284 * from the other side. 285 */ 286 static int 287 ngt_rcvdata(hook_p hook, item_p item) 288 { 289 const sc_p sc = NG_NODE_PRIVATE(NG_HOOK_NODE(hook)); 290 struct hookinfo *const hinfo = NG_HOOK_PRIVATE(hook); 291 struct hookinfo *dest; 292 struct hookinfo *dup; 293 int error = 0; 294 struct mbuf *m; 295 meta_p meta; 296 297 m = NGI_M(item); 298 meta = NGI_META(item); /* leave these owned by the item */ 299 /* Which hook? */ 300 if (hinfo == &sc->left) { 301 dup = &sc->left2right; 302 dest = &sc->right; 303 } else if (hinfo == &sc->right) { 304 dup = &sc->right2left; 305 dest = &sc->left; 306 } else if (hinfo == &sc->right2left) { 307 dup = NULL; 308 dest = &sc->right; 309 } else if (hinfo == &sc->left2right) { 310 dup = NULL; 311 dest = &sc->left; 312 } else { 313 panic("%s: no hook!", __FUNCTION__); 314 #ifdef RESTARTABLE_PANICS 315 return(EINVAL); 316 #endif 317 } 318 319 /* Update stats on incoming hook */ 320 hinfo->stats.inOctets += m->m_pkthdr.len; 321 hinfo->stats.inFrames++; 322 323 /* 324 * Don't make a copy if only the dup hook exists. 325 */ 326 if ((dup && dup->hook) && (dest->hook == NULL)) { 327 dest = dup; 328 dup = NULL; 329 } 330 331 /* Duplicate packet and meta info if requried */ 332 if (dup != NULL) { 333 struct mbuf *m2; 334 meta_p meta2; 335 336 /* Copy packet (failure will not stop the original)*/ 337 m2 = m_dup(m, M_NOWAIT); 338 if (m2) { 339 340 /* Copy meta info */ 341 /* If we can't get a copy, tough.. */ 342 if (meta != NULL) { 343 meta2 = ng_copy_meta(meta); 344 } else 345 meta2 = NULL; 346 347 /* Deliver duplicate */ 348 dup->stats.outOctets += m->m_pkthdr.len; 349 dup->stats.outFrames++; 350 NG_SEND_DATA(error, dup->hook, m2, meta2); 351 } 352 } 353 /* Deliver frame out destination hook */ 354 dest->stats.outOctets += m->m_pkthdr.len; 355 dest->stats.outFrames++; 356 if (dest->hook) 357 NG_FWD_ITEM_HOOK(error, item, dest->hook); 358 else 359 NG_FREE_ITEM(item); 360 return (0); 361 } 362 363 /* 364 * Shutdown processing 365 * 366 * This is tricky. If we have both a left and right hook, then we 367 * probably want to extricate ourselves and leave the two peers 368 * still linked to each other. Otherwise we should just shut down as 369 * a normal node would. 370 * 371 * To keep the scope of info correct the routine to "extract" a node 372 * from two links is in ng_base.c. 373 */ 374 static int 375 ngt_shutdown(node_p node) 376 { 377 const sc_p privdata = NG_NODE_PRIVATE(node); 378 379 #if 0 /* can never happen as cutlinks is already called */ 380 if (privdata->left.hook && privdata->right.hook) 381 ng_bypass(privdata->left.hook, privdata->right.hook); 382 #endif 383 NG_NODE_SET_PRIVATE(node, NULL); 384 NG_NODE_UNREF(privdata->node); 385 FREE(privdata, M_NETGRAPH); 386 return (0); 387 } 388 389 /* 390 * Hook disconnection 391 */ 392 static int 393 ngt_disconnect(hook_p hook) 394 { 395 struct hookinfo *const hinfo = NG_HOOK_PRIVATE(hook); 396 397 KASSERT(hinfo != NULL, ("%s: null info", __FUNCTION__)); 398 hinfo->hook = NULL; 399 if ((NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0) 400 && (NG_NODE_IS_VALID(NG_HOOK_NODE(hook)))) 401 ng_rmnode_self(NG_HOOK_NODE(hook)); 402 return (0); 403 } 404 405