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: src/sys/netgraph/ng_tee.c,v 1.7.2.5 2002/07/02 23:44:03 archie Exp $ 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 "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_rmnode; 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_field ng_tee_hookstat_type_fields[] 89 = 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_fields 93 }; 94 95 /* Parse type for struct ng_tee_stats */ 96 static const struct ng_parse_struct_field ng_tee_stats_type_fields[] 97 = 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_fields 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_VERSION, 132 NG_TEE_NODE_TYPE, 133 NULL, 134 ngt_constructor, 135 ngt_rcvmsg, 136 ngt_rmnode, 137 ngt_newhook, 138 NULL, 139 NULL, 140 ngt_rcvdata, 141 ngt_rcvdata, 142 ngt_disconnect, 143 ng_tee_cmds 144 }; 145 NETGRAPH_INIT(tee, &ng_tee_typestruct); 146 147 /* 148 * Node constructor 149 */ 150 static int 151 ngt_constructor(node_p *nodep) 152 { 153 sc_p privdata; 154 int error = 0; 155 156 privdata = kmalloc(sizeof(*privdata), M_NETGRAPH, M_NOWAIT | M_ZERO); 157 if (privdata == NULL) 158 return (ENOMEM); 159 160 if ((error = ng_make_node_common(&ng_tee_typestruct, nodep))) { 161 kfree(privdata, M_NETGRAPH); 162 return (error); 163 } 164 (*nodep)->private = privdata; 165 privdata->node = *nodep; 166 return (0); 167 } 168 169 /* 170 * Add a hook 171 */ 172 static int 173 ngt_newhook(node_p node, hook_p hook, const char *name) 174 { 175 const sc_p sc = node->private; 176 177 if (strcmp(name, NG_TEE_HOOK_RIGHT) == 0) { 178 sc->right.hook = hook; 179 bzero(&sc->right.stats, sizeof(sc->right.stats)); 180 hook->private = &sc->right; 181 } else if (strcmp(name, NG_TEE_HOOK_LEFT) == 0) { 182 sc->left.hook = hook; 183 bzero(&sc->left.stats, sizeof(sc->left.stats)); 184 hook->private = &sc->left; 185 } else if (strcmp(name, NG_TEE_HOOK_RIGHT2LEFT) == 0) { 186 sc->right2left.hook = hook; 187 bzero(&sc->right2left.stats, sizeof(sc->right2left.stats)); 188 hook->private = &sc->right2left; 189 } else if (strcmp(name, NG_TEE_HOOK_LEFT2RIGHT) == 0) { 190 sc->left2right.hook = hook; 191 bzero(&sc->left2right.stats, sizeof(sc->left2right.stats)); 192 hook->private = &sc->left2right; 193 } else 194 return (EINVAL); 195 return (0); 196 } 197 198 /* 199 * Receive a control message 200 */ 201 static int 202 ngt_rcvmsg(node_p node, struct ng_mesg *msg, const char *retaddr, 203 struct ng_mesg **rptr) 204 { 205 const sc_p sc = node->private; 206 struct ng_mesg *resp = NULL; 207 int error = 0; 208 209 switch (msg->header.typecookie) { 210 case NGM_TEE_COOKIE: 211 switch (msg->header.cmd) { 212 case NGM_TEE_GET_STATS: 213 case NGM_TEE_CLR_STATS: 214 case NGM_TEE_GETCLR_STATS: 215 { 216 struct ng_tee_stats *stats; 217 218 if (msg->header.cmd != NGM_TEE_CLR_STATS) { 219 NG_MKRESPONSE(resp, msg, 220 sizeof(*stats), M_NOWAIT); 221 if (resp == NULL) { 222 error = ENOMEM; 223 goto done; 224 } 225 stats = (struct ng_tee_stats *)resp->data; 226 bcopy(&sc->right.stats, &stats->right, 227 sizeof(stats->right)); 228 bcopy(&sc->left.stats, &stats->left, 229 sizeof(stats->left)); 230 bcopy(&sc->right2left.stats, &stats->right2left, 231 sizeof(stats->right2left)); 232 bcopy(&sc->left2right.stats, &stats->left2right, 233 sizeof(stats->left2right)); 234 } 235 if (msg->header.cmd != NGM_TEE_GET_STATS) { 236 bzero(&sc->right.stats, 237 sizeof(sc->right.stats)); 238 bzero(&sc->left.stats, 239 sizeof(sc->left.stats)); 240 bzero(&sc->right2left.stats, 241 sizeof(sc->right2left.stats)); 242 bzero(&sc->left2right.stats, 243 sizeof(sc->left2right.stats)); 244 } 245 break; 246 } 247 default: 248 error = EINVAL; 249 break; 250 } 251 break; 252 default: 253 error = EINVAL; 254 break; 255 } 256 if (rptr) 257 *rptr = resp; 258 else if (resp) 259 kfree(resp, M_NETGRAPH); 260 261 done: 262 kfree(msg, M_NETGRAPH); 263 return (error); 264 } 265 266 /* 267 * Receive data on a hook 268 * 269 * If data comes in the right link send a copy out right2left, and then 270 * send the original onwards out through the left link. 271 * Do the opposite for data coming in from the left link. 272 * Data coming in right2left or left2right is forwarded 273 * on through the appropriate destination hook as if it had come 274 * from the other side. 275 */ 276 static int 277 ngt_rcvdata(hook_p hook, struct mbuf *m, meta_p meta) 278 { 279 const sc_p sc = hook->node->private; 280 struct hookinfo *const hinfo = (struct hookinfo *) hook->private; 281 struct hookinfo *dest; 282 struct hookinfo *dup; 283 int error = 0; 284 285 /* Which hook? */ 286 if (hinfo == &sc->left) { 287 dup = &sc->left2right; 288 dest = &sc->right; 289 } else if (hinfo == &sc->right) { 290 dup = &sc->right2left; 291 dest = &sc->left; 292 } else if (hinfo == &sc->right2left) { 293 dup = NULL; 294 dest = &sc->right; 295 } else if (hinfo == &sc->left2right) { 296 dup = NULL; 297 dest = &sc->left; 298 } else 299 panic("%s: no hook!", __func__); 300 301 /* Update stats on incoming hook */ 302 hinfo->stats.inOctets += m->m_pkthdr.len; 303 hinfo->stats.inFrames++; 304 305 /* Duplicate packet and meta info if requried */ 306 if (dup != NULL) { 307 struct mbuf *m2; 308 meta_p meta2; 309 310 /* Copy packet */ 311 m2 = m_dup(m, M_NOWAIT); 312 if (m2 == NULL) { 313 NG_FREE_DATA(m, meta); 314 return (ENOBUFS); 315 } 316 317 /* Copy meta info */ 318 if (meta != NULL) { 319 meta2 = kmalloc(meta->used_len, M_NETGRAPH, M_NOWAIT); 320 if (meta2 == NULL) { 321 m_freem(m2); 322 NG_FREE_DATA(m, meta); 323 return (ENOMEM); 324 } 325 bcopy(meta, meta2, meta->used_len); 326 meta2->allocated_len = meta->used_len; 327 } else 328 meta2 = NULL; 329 330 /* Deliver duplicate */ 331 dup->stats.outOctets += m->m_pkthdr.len; 332 dup->stats.outFrames++; 333 NG_SEND_DATA(error, dup->hook, m2, meta2); 334 } 335 336 /* Deliver frame out destination hook */ 337 dest->stats.outOctets += m->m_pkthdr.len; 338 dest->stats.outFrames++; 339 NG_SEND_DATA(error, dest->hook, m, meta); 340 return (error); 341 } 342 343 /* 344 * Shutdown processing 345 * 346 * This is tricky. If we have both a left and right hook, then we 347 * probably want to extricate ourselves and leave the two peers 348 * still linked to each other. Otherwise we should just shut down as 349 * a normal node would. 350 * 351 * To keep the scope of info correct the routine to "extract" a node 352 * from two links is in ng_base.c. 353 */ 354 static int 355 ngt_rmnode(node_p node) 356 { 357 const sc_p privdata = node->private; 358 359 node->flags |= NG_INVALID; 360 if (privdata->left.hook && privdata->right.hook) 361 ng_bypass(privdata->left.hook, privdata->right.hook); 362 ng_cutlinks(node); 363 ng_unname(node); 364 node->private = NULL; 365 ng_unref(privdata->node); 366 kfree(privdata, M_NETGRAPH); 367 return (0); 368 } 369 370 /* 371 * Hook disconnection 372 */ 373 static int 374 ngt_disconnect(hook_p hook) 375 { 376 struct hookinfo *const hinfo = (struct hookinfo *) hook->private; 377 378 KASSERT(hinfo != NULL, ("%s: null info", __func__)); 379 hinfo->hook = NULL; 380 if (hook->node->numhooks == 0) 381 ng_rmnode(hook->node); 382 return (0); 383 } 384 385