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 * $FreeBSD$ 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 <netgraph/ng_message.h> 61 #include <netgraph/netgraph.h> 62 #include <netgraph/ng_parse.h> 63 #include <netgraph/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 152 ng_tee_constructor(node_p node) 153 { 154 sc_p privdata; 155 156 privdata = malloc(sizeof(*privdata), M_NETGRAPH, M_WAITOK | M_ZERO); 157 158 NG_NODE_SET_PRIVATE(node, privdata); 159 return (0); 160 } 161 162 /* 163 * Add a hook 164 */ 165 static int 166 ng_tee_newhook(node_p node, hook_p hook, const char *name) 167 { 168 sc_p privdata = NG_NODE_PRIVATE(node); 169 hi_p hinfo; 170 171 /* Precalculate internal pathes. */ 172 if (strcmp(name, NG_TEE_HOOK_RIGHT) == 0) { 173 hinfo = &privdata->right; 174 if (privdata->left.dest) 175 privdata->left.dup = privdata->left.dest; 176 privdata->left.dest = hinfo; 177 privdata->right2left.dest = hinfo; 178 } else if (strcmp(name, NG_TEE_HOOK_LEFT) == 0) { 179 hinfo = &privdata->left; 180 if (privdata->right.dest) 181 privdata->right.dup = privdata->right.dest; 182 privdata->right.dest = hinfo; 183 privdata->left2right.dest = hinfo; 184 } else if (strcmp(name, NG_TEE_HOOK_RIGHT2LEFT) == 0) { 185 hinfo = &privdata->right2left; 186 if (privdata->right.dest) 187 privdata->right.dup = hinfo; 188 else 189 privdata->right.dest = hinfo; 190 } else if (strcmp(name, NG_TEE_HOOK_LEFT2RIGHT) == 0) { 191 hinfo = &privdata->left2right; 192 if (privdata->left.dest) 193 privdata->left.dup = hinfo; 194 else 195 privdata->left.dest = hinfo; 196 } else 197 return (EINVAL); 198 hinfo->hook = hook; 199 bzero(&hinfo->stats, sizeof(hinfo->stats)); 200 NG_HOOK_SET_PRIVATE(hook, hinfo); 201 return (0); 202 } 203 204 /* 205 * Receive a control message 206 */ 207 static int 208 ng_tee_rcvmsg(node_p node, item_p item, hook_p lasthook) 209 { 210 const sc_p sc = NG_NODE_PRIVATE(node); 211 struct ng_mesg *resp = NULL; 212 int error = 0; 213 struct ng_mesg *msg; 214 215 NGI_GET_MSG(item, msg); 216 switch (msg->header.typecookie) { 217 case NGM_TEE_COOKIE: 218 switch (msg->header.cmd) { 219 case NGM_TEE_GET_STATS: 220 case NGM_TEE_CLR_STATS: 221 case NGM_TEE_GETCLR_STATS: 222 { 223 struct ng_tee_stats *stats; 224 225 if (msg->header.cmd != NGM_TEE_CLR_STATS) { 226 NG_MKRESPONSE(resp, msg, 227 sizeof(*stats), M_NOWAIT); 228 if (resp == NULL) { 229 error = ENOMEM; 230 goto done; 231 } 232 stats = (struct ng_tee_stats *)resp->data; 233 bcopy(&sc->right.stats, &stats->right, 234 sizeof(stats->right)); 235 bcopy(&sc->left.stats, &stats->left, 236 sizeof(stats->left)); 237 bcopy(&sc->right2left.stats, &stats->right2left, 238 sizeof(stats->right2left)); 239 bcopy(&sc->left2right.stats, &stats->left2right, 240 sizeof(stats->left2right)); 241 } 242 if (msg->header.cmd != NGM_TEE_GET_STATS) { 243 bzero(&sc->right.stats, 244 sizeof(sc->right.stats)); 245 bzero(&sc->left.stats, 246 sizeof(sc->left.stats)); 247 bzero(&sc->right2left.stats, 248 sizeof(sc->right2left.stats)); 249 bzero(&sc->left2right.stats, 250 sizeof(sc->left2right.stats)); 251 } 252 break; 253 } 254 default: 255 error = EINVAL; 256 break; 257 } 258 break; 259 case NGM_FLOW_COOKIE: 260 if (lasthook == sc->left.hook || lasthook == sc->right.hook) { 261 hi_p const hinfo = NG_HOOK_PRIVATE(lasthook); 262 if (hinfo && hinfo->dest) { 263 NGI_MSG(item) = msg; 264 NG_FWD_ITEM_HOOK(error, item, hinfo->dest->hook); 265 return (error); 266 } 267 } 268 break; 269 default: 270 error = EINVAL; 271 break; 272 } 273 done: 274 NG_RESPOND_MSG(error, node, item, resp); 275 NG_FREE_MSG(msg); 276 return (error); 277 } 278 279 /* 280 * Receive data on a hook 281 * 282 * If data comes in the right link send a copy out right2left, and then 283 * send the original onwards out through the left link. 284 * Do the opposite for data coming in from the left link. 285 * Data coming in right2left or left2right is forwarded 286 * on through the appropriate destination hook as if it had come 287 * from the other side. 288 */ 289 static int 290 ng_tee_rcvdata(hook_p hook, item_p item) 291 { 292 const hi_p hinfo = NG_HOOK_PRIVATE(hook); 293 hi_p h; 294 int error = 0; 295 struct mbuf *m; 296 297 m = NGI_M(item); 298 299 /* Update stats on incoming hook */ 300 hinfo->stats.inOctets += m->m_pkthdr.len; 301 hinfo->stats.inFrames++; 302 303 /* Duplicate packet if requried */ 304 if (hinfo->dup) { 305 struct mbuf *m2; 306 307 /* Copy packet (failure will not stop the original)*/ 308 m2 = m_dup(m, M_NOWAIT); 309 if (m2) { 310 /* Deliver duplicate */ 311 h = hinfo->dup; 312 NG_SEND_DATA_ONLY(error, h->hook, m2); 313 if (error == 0) { 314 h->stats.outOctets += m->m_pkthdr.len; 315 h->stats.outFrames++; 316 } 317 } 318 } 319 /* Deliver frame out destination hook */ 320 if (hinfo->dest) { 321 h = hinfo->dest; 322 h->stats.outOctets += m->m_pkthdr.len; 323 h->stats.outFrames++; 324 NG_FWD_ITEM_HOOK(error, item, h->hook); 325 } else 326 NG_FREE_ITEM(item); 327 return (error); 328 } 329 330 /* 331 * We are going to be shut down soon 332 * 333 * If we have both a left and right hook, then we probably want to extricate 334 * ourselves and leave the two peers still linked to each other. Otherwise we 335 * should just shut down as a normal node would. 336 */ 337 static int 338 ng_tee_close(node_p node) 339 { 340 const sc_p privdata = NG_NODE_PRIVATE(node); 341 342 if (privdata->left.hook && privdata->right.hook) 343 ng_bypass(privdata->left.hook, privdata->right.hook); 344 345 return (0); 346 } 347 348 /* 349 * Shutdown processing 350 */ 351 static int 352 ng_tee_shutdown(node_p node) 353 { 354 const sc_p privdata = NG_NODE_PRIVATE(node); 355 356 NG_NODE_SET_PRIVATE(node, NULL); 357 free(privdata, M_NETGRAPH); 358 NG_NODE_UNREF(node); 359 return (0); 360 } 361 362 /* 363 * Hook disconnection 364 */ 365 static int 366 ng_tee_disconnect(hook_p hook) 367 { 368 sc_p sc = NG_NODE_PRIVATE(NG_HOOK_NODE(hook)); 369 hi_p const hinfo = NG_HOOK_PRIVATE(hook); 370 371 KASSERT(hinfo != NULL, ("%s: null info", __func__)); 372 hinfo->hook = NULL; 373 374 /* Recalculate internal pathes. */ 375 if (sc->left.dest == hinfo) { 376 sc->left.dest = sc->left.dup; 377 sc->left.dup = NULL; 378 } else if (sc->left.dup == hinfo) 379 sc->left.dup = NULL; 380 if (sc->right.dest == hinfo) { 381 sc->right.dest = sc->right.dup; 382 sc->right.dup = NULL; 383 } else if (sc->right.dup == hinfo) 384 sc->right.dup = NULL; 385 if (sc->left2right.dest == hinfo) 386 sc->left2right.dest = NULL; 387 if (sc->right2left.dest == hinfo) 388 sc->right2left.dest = NULL; 389 390 /* Die when last hook disconnected. */ 391 if ((NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0) && 392 NG_NODE_IS_VALID(NG_HOOK_NODE(hook))) 393 ng_rmnode_self(NG_HOOK_NODE(hook)); 394 return (0); 395 } 396