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