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 MALLOC(privdata, sc_p, sizeof(*privdata), M_NETGRAPH, M_NOWAIT|M_ZERO); 157 if (privdata == NULL) 158 return (ENOMEM); 159 160 NG_NODE_SET_PRIVATE(node, privdata); 161 return (0); 162 } 163 164 /* 165 * Add a hook 166 */ 167 static int 168 ng_tee_newhook(node_p node, hook_p hook, const char *name) 169 { 170 sc_p privdata = NG_NODE_PRIVATE(node); 171 hi_p hinfo; 172 173 /* Precalculate internal pathes. */ 174 if (strcmp(name, NG_TEE_HOOK_RIGHT) == 0) { 175 hinfo = &privdata->right; 176 if (privdata->left.dest) 177 privdata->left.dup = privdata->left.dest; 178 privdata->left.dest = hinfo; 179 privdata->right2left.dest = hinfo; 180 } else if (strcmp(name, NG_TEE_HOOK_LEFT) == 0) { 181 hinfo = &privdata->left; 182 if (privdata->right.dest) 183 privdata->right.dup = privdata->right.dest; 184 privdata->right.dest = hinfo; 185 privdata->left2right.dest = hinfo; 186 } else if (strcmp(name, NG_TEE_HOOK_RIGHT2LEFT) == 0) { 187 hinfo = &privdata->right2left; 188 if (privdata->right.dest) 189 privdata->right.dup = hinfo; 190 else 191 privdata->right.dest = hinfo; 192 } else if (strcmp(name, NG_TEE_HOOK_LEFT2RIGHT) == 0) { 193 hinfo = &privdata->left2right; 194 if (privdata->left.dest) 195 privdata->left.dup = hinfo; 196 else 197 privdata->left.dest = hinfo; 198 } else 199 return (EINVAL); 200 hinfo->hook = hook; 201 bzero(&hinfo->stats, sizeof(hinfo->stats)); 202 NG_HOOK_SET_PRIVATE(hook, hinfo); 203 return (0); 204 } 205 206 /* 207 * Receive a control message 208 */ 209 static int 210 ng_tee_rcvmsg(node_p node, item_p item, hook_p lasthook) 211 { 212 const sc_p sc = NG_NODE_PRIVATE(node); 213 struct ng_mesg *resp = NULL; 214 int error = 0; 215 struct ng_mesg *msg; 216 217 NGI_GET_MSG(item, msg); 218 switch (msg->header.typecookie) { 219 case NGM_TEE_COOKIE: 220 switch (msg->header.cmd) { 221 case NGM_TEE_GET_STATS: 222 case NGM_TEE_CLR_STATS: 223 case NGM_TEE_GETCLR_STATS: 224 { 225 struct ng_tee_stats *stats; 226 227 if (msg->header.cmd != NGM_TEE_CLR_STATS) { 228 NG_MKRESPONSE(resp, msg, 229 sizeof(*stats), M_NOWAIT); 230 if (resp == NULL) { 231 error = ENOMEM; 232 goto done; 233 } 234 stats = (struct ng_tee_stats *)resp->data; 235 bcopy(&sc->right.stats, &stats->right, 236 sizeof(stats->right)); 237 bcopy(&sc->left.stats, &stats->left, 238 sizeof(stats->left)); 239 bcopy(&sc->right2left.stats, &stats->right2left, 240 sizeof(stats->right2left)); 241 bcopy(&sc->left2right.stats, &stats->left2right, 242 sizeof(stats->left2right)); 243 } 244 if (msg->header.cmd != NGM_TEE_GET_STATS) { 245 bzero(&sc->right.stats, 246 sizeof(sc->right.stats)); 247 bzero(&sc->left.stats, 248 sizeof(sc->left.stats)); 249 bzero(&sc->right2left.stats, 250 sizeof(sc->right2left.stats)); 251 bzero(&sc->left2right.stats, 252 sizeof(sc->left2right.stats)); 253 } 254 break; 255 } 256 default: 257 error = EINVAL; 258 break; 259 } 260 break; 261 case NGM_FLOW_COOKIE: 262 if (lasthook == sc->left.hook || lasthook == sc->right.hook) { 263 hi_p const hinfo = NG_HOOK_PRIVATE(lasthook); 264 if (hinfo && hinfo->dest) { 265 NGI_MSG(item) = msg; 266 NG_FWD_ITEM_HOOK(error, item, hinfo->dest->hook); 267 return (error); 268 } 269 } 270 break; 271 default: 272 error = EINVAL; 273 break; 274 } 275 done: 276 NG_RESPOND_MSG(error, node, item, resp); 277 NG_FREE_MSG(msg); 278 return (error); 279 } 280 281 /* 282 * Receive data on a hook 283 * 284 * If data comes in the right link send a copy out right2left, and then 285 * send the original onwards out through the left link. 286 * Do the opposite for data coming in from the left link. 287 * Data coming in right2left or left2right is forwarded 288 * on through the appropriate destination hook as if it had come 289 * from the other side. 290 */ 291 static int 292 ng_tee_rcvdata(hook_p hook, item_p item) 293 { 294 const hi_p hinfo = NG_HOOK_PRIVATE(hook); 295 hi_p h; 296 int error = 0; 297 struct mbuf *m; 298 299 m = NGI_M(item); 300 301 /* Update stats on incoming hook */ 302 hinfo->stats.inOctets += m->m_pkthdr.len; 303 hinfo->stats.inFrames++; 304 305 /* Duplicate packet if requried */ 306 if (hinfo->dup) { 307 struct mbuf *m2; 308 309 /* Copy packet (failure will not stop the original)*/ 310 m2 = m_dup(m, M_DONTWAIT); 311 if (m2) { 312 /* Deliver duplicate */ 313 h = hinfo->dup; 314 NG_SEND_DATA_ONLY(error, h->hook, m2); 315 if (error == 0) { 316 h->stats.outOctets += m->m_pkthdr.len; 317 h->stats.outFrames++; 318 } 319 } 320 } 321 /* Deliver frame out destination hook */ 322 if (hinfo->dest) { 323 h = hinfo->dest; 324 h->stats.outOctets += m->m_pkthdr.len; 325 h->stats.outFrames++; 326 NG_FWD_ITEM_HOOK(error, item, h->hook); 327 } else 328 NG_FREE_ITEM(item); 329 return (error); 330 } 331 332 /* 333 * We are going to be shut down soon 334 * 335 * If we have both a left and right hook, then we probably want to extricate 336 * ourselves and leave the two peers still linked to each other. Otherwise we 337 * should just shut down as a normal node would. 338 */ 339 static int 340 ng_tee_close(node_p node) 341 { 342 const sc_p privdata = NG_NODE_PRIVATE(node); 343 344 if (privdata->left.hook && privdata->right.hook) 345 ng_bypass(privdata->left.hook, privdata->right.hook); 346 347 return (0); 348 } 349 350 /* 351 * Shutdown processing 352 */ 353 static int 354 ng_tee_shutdown(node_p node) 355 { 356 const sc_p privdata = NG_NODE_PRIVATE(node); 357 358 NG_NODE_SET_PRIVATE(node, NULL); 359 FREE(privdata, M_NETGRAPH); 360 return (0); 361 } 362 363 /* 364 * Hook disconnection 365 */ 366 static int 367 ng_tee_disconnect(hook_p hook) 368 { 369 sc_p sc = NG_NODE_PRIVATE(NG_HOOK_NODE(hook)); 370 hi_p const hinfo = NG_HOOK_PRIVATE(hook); 371 372 KASSERT(hinfo != NULL, ("%s: null info", __func__)); 373 hinfo->hook = NULL; 374 375 /* Recalculate internal pathes. */ 376 if (sc->left.dest == hinfo) { 377 sc->left.dest = sc->left.dup; 378 sc->left.dup = NULL; 379 } else if (sc->left.dup == hinfo) 380 sc->left.dup = NULL; 381 if (sc->right.dest == hinfo) { 382 sc->right.dest = sc->right.dup; 383 sc->right.dup = NULL; 384 } else if (sc->right.dup == hinfo) 385 sc->right.dup = NULL; 386 if (sc->left2right.dest == hinfo) 387 sc->left2right.dest = NULL; 388 if (sc->right2left.dest == hinfo) 389 sc->right2left.dest = NULL; 390 391 /* Die when last hook disconnected. */ 392 if ((NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0) && 393 NG_NODE_IS_VALID(NG_HOOK_NODE(hook))) 394 ng_rmnode_self(NG_HOOK_NODE(hook)); 395 return (0); 396 } 397