1 /*- 2 * Copyright (c) 2003 IPNET Internet Communication Company 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 * 26 * Author: Ruslan Ermilov <ru@FreeBSD.org> 27 * 28 * $FreeBSD$ 29 */ 30 31 #include <sys/param.h> 32 #include <sys/errno.h> 33 #include <sys/kernel.h> 34 #include <sys/malloc.h> 35 #include <sys/mbuf.h> 36 #include <sys/queue.h> 37 #include <sys/socket.h> 38 #include <sys/systm.h> 39 40 #include <net/ethernet.h> 41 #include <net/if.h> 42 #include <net/if_vlan_var.h> 43 44 #include <netgraph/ng_message.h> 45 #include <netgraph/ng_parse.h> 46 #include <netgraph/ng_vlan.h> 47 #include <netgraph/netgraph.h> 48 49 static ng_constructor_t ng_vlan_constructor; 50 static ng_rcvmsg_t ng_vlan_rcvmsg; 51 static ng_shutdown_t ng_vlan_shutdown; 52 static ng_newhook_t ng_vlan_newhook; 53 static ng_rcvdata_t ng_vlan_rcvdata; 54 static ng_disconnect_t ng_vlan_disconnect; 55 56 /* Parse type for struct ng_vlan_filter. */ 57 static const struct ng_parse_struct_field ng_vlan_filter_fields[] = 58 NG_VLAN_FILTER_FIELDS; 59 static const struct ng_parse_type ng_vlan_filter_type = { 60 &ng_parse_struct_type, 61 &ng_vlan_filter_fields 62 }; 63 64 static int 65 ng_vlan_getTableLength(const struct ng_parse_type *type, 66 const u_char *start, const u_char *buf) 67 { 68 const struct ng_vlan_table *const table = 69 (const struct ng_vlan_table *)(buf - sizeof(u_int32_t)); 70 71 return table->n; 72 } 73 74 /* Parse type for struct ng_vlan_table. */ 75 static const struct ng_parse_array_info ng_vlan_table_array_info = { 76 &ng_vlan_filter_type, 77 ng_vlan_getTableLength 78 }; 79 static const struct ng_parse_type ng_vlan_table_array_type = { 80 &ng_parse_array_type, 81 &ng_vlan_table_array_info 82 }; 83 static const struct ng_parse_struct_field ng_vlan_table_fields[] = 84 NG_VLAN_TABLE_FIELDS; 85 static const struct ng_parse_type ng_vlan_table_type = { 86 &ng_parse_struct_type, 87 &ng_vlan_table_fields 88 }; 89 90 /* List of commands and how to convert arguments to/from ASCII. */ 91 static const struct ng_cmdlist ng_vlan_cmdlist[] = { 92 { 93 NGM_VLAN_COOKIE, 94 NGM_VLAN_ADD_FILTER, 95 "addfilter", 96 &ng_vlan_filter_type, 97 NULL 98 }, 99 { 100 NGM_VLAN_COOKIE, 101 NGM_VLAN_DEL_FILTER, 102 "delfilter", 103 &ng_parse_hookbuf_type, 104 NULL 105 }, 106 { 107 NGM_VLAN_COOKIE, 108 NGM_VLAN_GET_TABLE, 109 "gettable", 110 NULL, 111 &ng_vlan_table_type 112 }, 113 { 0 } 114 }; 115 116 static struct ng_type ng_vlan_typestruct = { 117 .version = NG_ABI_VERSION, 118 .name = NG_VLAN_NODE_TYPE, 119 .constructor = ng_vlan_constructor, 120 .rcvmsg = ng_vlan_rcvmsg, 121 .shutdown = ng_vlan_shutdown, 122 .newhook = ng_vlan_newhook, 123 .rcvdata = ng_vlan_rcvdata, 124 .disconnect = ng_vlan_disconnect, 125 .cmdlist = ng_vlan_cmdlist, 126 }; 127 NETGRAPH_INIT(vlan, &ng_vlan_typestruct); 128 129 struct filter { 130 LIST_ENTRY(filter) next; 131 u_int16_t vlan; 132 hook_p hook; 133 }; 134 135 #define HASHSIZE 16 136 #define HASH(id) ((((id) >> 8) ^ ((id) >> 4) ^ (id)) & 0x0f) 137 LIST_HEAD(filterhead, filter); 138 139 typedef struct { 140 hook_p downstream_hook; 141 hook_p nomatch_hook; 142 struct filterhead hashtable[HASHSIZE]; 143 u_int32_t nent; 144 } *priv_p; 145 146 static struct filter * 147 ng_vlan_findentry(priv_p priv, u_int16_t vlan) 148 { 149 struct filterhead *chain = &priv->hashtable[HASH(vlan)]; 150 struct filter *f; 151 152 LIST_FOREACH(f, chain, next) 153 if (f->vlan == vlan) 154 return (f); 155 return (NULL); 156 } 157 158 static int 159 ng_vlan_constructor(node_p node) 160 { 161 priv_p priv; 162 int i; 163 164 priv = malloc(sizeof(*priv), M_NETGRAPH, M_WAITOK | M_ZERO); 165 for (i = 0; i < HASHSIZE; i++) 166 LIST_INIT(&priv->hashtable[i]); 167 NG_NODE_SET_PRIVATE(node, priv); 168 return (0); 169 } 170 171 static int 172 ng_vlan_newhook(node_p node, hook_p hook, const char *name) 173 { 174 const priv_p priv = NG_NODE_PRIVATE(node); 175 176 if (strcmp(name, NG_VLAN_HOOK_DOWNSTREAM) == 0) 177 priv->downstream_hook = hook; 178 else if (strcmp(name, NG_VLAN_HOOK_NOMATCH) == 0) 179 priv->nomatch_hook = hook; 180 else { 181 /* 182 * Any other hook name is valid and can 183 * later be associated with a filter rule. 184 */ 185 } 186 NG_HOOK_SET_PRIVATE(hook, NULL); 187 return (0); 188 } 189 190 static int 191 ng_vlan_rcvmsg(node_p node, item_p item, hook_p lasthook) 192 { 193 const priv_p priv = NG_NODE_PRIVATE(node); 194 int error = 0; 195 struct ng_mesg *msg, *resp = NULL; 196 struct ng_vlan_filter *vf; 197 struct filter *f; 198 hook_p hook; 199 struct ng_vlan_table *t; 200 int i; 201 202 NGI_GET_MSG(item, msg); 203 /* Deal with message according to cookie and command. */ 204 switch (msg->header.typecookie) { 205 case NGM_VLAN_COOKIE: 206 switch (msg->header.cmd) { 207 case NGM_VLAN_ADD_FILTER: 208 /* Check that message is long enough. */ 209 if (msg->header.arglen != sizeof(*vf)) { 210 error = EINVAL; 211 break; 212 } 213 vf = (struct ng_vlan_filter *)msg->data; 214 /* Sanity check the VLAN ID value. */ 215 if (vf->vlan & ~EVL_VLID_MASK) { 216 error = EINVAL; 217 break; 218 } 219 /* Check that a referenced hook exists. */ 220 hook = ng_findhook(node, vf->hook); 221 if (hook == NULL) { 222 error = ENOENT; 223 break; 224 } 225 /* And is not one of the special hooks. */ 226 if (hook == priv->downstream_hook || 227 hook == priv->nomatch_hook) { 228 error = EINVAL; 229 break; 230 } 231 /* And is not already in service. */ 232 if (NG_HOOK_PRIVATE(hook) != NULL) { 233 error = EEXIST; 234 break; 235 } 236 /* Check we don't already trap this VLAN. */ 237 if (ng_vlan_findentry(priv, vf->vlan)) { 238 error = EEXIST; 239 break; 240 } 241 /* Create filter. */ 242 f = malloc(sizeof(*f), 243 M_NETGRAPH, M_NOWAIT | M_ZERO); 244 if (f == NULL) { 245 error = ENOMEM; 246 break; 247 } 248 /* Link filter and hook together. */ 249 f->hook = hook; 250 f->vlan = vf->vlan; 251 NG_HOOK_SET_PRIVATE(hook, f); 252 /* Register filter in a hash table. */ 253 LIST_INSERT_HEAD( 254 &priv->hashtable[HASH(f->vlan)], f, next); 255 priv->nent++; 256 break; 257 case NGM_VLAN_DEL_FILTER: 258 /* Check that message is long enough. */ 259 if (msg->header.arglen != NG_HOOKSIZ) { 260 error = EINVAL; 261 break; 262 } 263 /* Check that hook exists and is active. */ 264 hook = ng_findhook(node, (char *)msg->data); 265 if (hook == NULL || 266 (f = NG_HOOK_PRIVATE(hook)) == NULL) { 267 error = ENOENT; 268 break; 269 } 270 /* Purge a rule that refers to this hook. */ 271 NG_HOOK_SET_PRIVATE(hook, NULL); 272 LIST_REMOVE(f, next); 273 priv->nent--; 274 free(f, M_NETGRAPH); 275 break; 276 case NGM_VLAN_GET_TABLE: 277 NG_MKRESPONSE(resp, msg, sizeof(*t) + 278 priv->nent * sizeof(*t->filter), M_NOWAIT); 279 if (resp == NULL) { 280 error = ENOMEM; 281 break; 282 } 283 t = (struct ng_vlan_table *)resp->data; 284 t->n = priv->nent; 285 vf = &t->filter[0]; 286 for (i = 0; i < HASHSIZE; i++) { 287 LIST_FOREACH(f, &priv->hashtable[i], next) { 288 vf->vlan = f->vlan; 289 strncpy(vf->hook, NG_HOOK_NAME(f->hook), 290 NG_HOOKSIZ); 291 vf++; 292 } 293 } 294 break; 295 default: /* Unknown command. */ 296 error = EINVAL; 297 break; 298 } 299 break; 300 case NGM_FLOW_COOKIE: 301 { 302 struct ng_mesg *copy; 303 struct filterhead *chain; 304 struct filter *f; 305 306 /* 307 * Flow control messages should come only 308 * from downstream. 309 */ 310 311 if (lasthook == NULL) 312 break; 313 if (lasthook != priv->downstream_hook) 314 break; 315 316 /* Broadcast the event to all uplinks. */ 317 for (i = 0, chain = priv->hashtable; i < HASHSIZE; 318 i++, chain++) 319 LIST_FOREACH(f, chain, next) { 320 NG_COPYMESSAGE(copy, msg, M_NOWAIT); 321 if (copy == NULL) 322 continue; 323 NG_SEND_MSG_HOOK(error, node, copy, f->hook, 0); 324 } 325 326 break; 327 } 328 default: /* Unknown type cookie. */ 329 error = EINVAL; 330 break; 331 } 332 NG_RESPOND_MSG(error, node, item, resp); 333 NG_FREE_MSG(msg); 334 return (error); 335 } 336 337 static int 338 ng_vlan_rcvdata(hook_p hook, item_p item) 339 { 340 const priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook)); 341 struct ether_header *eh; 342 struct ether_vlan_header *evl = NULL; 343 int error; 344 u_int16_t vlan; 345 struct mbuf *m; 346 struct filter *f; 347 348 /* Make sure we have an entire header. */ 349 NGI_GET_M(item, m); 350 if (m->m_len < sizeof(*eh) && 351 (m = m_pullup(m, sizeof(*eh))) == NULL) { 352 NG_FREE_ITEM(item); 353 return (EINVAL); 354 } 355 eh = mtod(m, struct ether_header *); 356 if (hook == priv->downstream_hook) { 357 /* 358 * If from downstream, select between a match hook 359 * or the nomatch hook. 360 */ 361 if (m->m_flags & M_VLANTAG || 362 eh->ether_type == htons(ETHERTYPE_VLAN)) { 363 if (m->m_flags & M_VLANTAG) { 364 /* 365 * Packet is tagged, m contains a normal 366 * Ethernet frame; tag is stored out-of-band. 367 */ 368 vlan = EVL_VLANOFTAG(m->m_pkthdr.ether_vtag); 369 } else { 370 if (m->m_len < sizeof(*evl) && 371 (m = m_pullup(m, sizeof(*evl))) == NULL) { 372 NG_FREE_ITEM(item); 373 return (EINVAL); 374 } 375 evl = mtod(m, struct ether_vlan_header *); 376 vlan = EVL_VLANOFTAG(ntohs(evl->evl_tag)); 377 } 378 if ((f = ng_vlan_findentry(priv, vlan)) != NULL) { 379 if (m->m_flags & M_VLANTAG) { 380 m->m_pkthdr.ether_vtag = 0; 381 m->m_flags &= ~M_VLANTAG; 382 } else { 383 evl->evl_encap_proto = evl->evl_proto; 384 bcopy(mtod(m, caddr_t), 385 mtod(m, caddr_t) + 386 ETHER_VLAN_ENCAP_LEN, 387 ETHER_HDR_LEN); 388 m_adj(m, ETHER_VLAN_ENCAP_LEN); 389 } 390 } 391 } else 392 f = NULL; 393 if (f != NULL) 394 NG_FWD_NEW_DATA(error, item, f->hook, m); 395 else 396 NG_FWD_NEW_DATA(error, item, priv->nomatch_hook, m); 397 } else { 398 /* 399 * It is heading towards the downstream. 400 * If from nomatch, pass it unmodified. 401 * Otherwise, do the VLAN encapsulation. 402 */ 403 if (hook != priv->nomatch_hook) { 404 if ((f = NG_HOOK_PRIVATE(hook)) == NULL) { 405 NG_FREE_ITEM(item); 406 NG_FREE_M(m); 407 return (EOPNOTSUPP); 408 } 409 M_PREPEND(m, ETHER_VLAN_ENCAP_LEN, M_DONTWAIT); 410 /* M_PREPEND takes care of m_len and m_pkthdr.len. */ 411 if (m == NULL || (m->m_len < sizeof(*evl) && 412 (m = m_pullup(m, sizeof(*evl))) == NULL)) { 413 NG_FREE_ITEM(item); 414 return (ENOMEM); 415 } 416 /* 417 * Transform the Ethernet header into an Ethernet header 418 * with 802.1Q encapsulation. 419 */ 420 bcopy(mtod(m, char *) + ETHER_VLAN_ENCAP_LEN, 421 mtod(m, char *), ETHER_HDR_LEN); 422 evl = mtod(m, struct ether_vlan_header *); 423 evl->evl_proto = evl->evl_encap_proto; 424 evl->evl_encap_proto = htons(ETHERTYPE_VLAN); 425 evl->evl_tag = htons(f->vlan); 426 } 427 NG_FWD_NEW_DATA(error, item, priv->downstream_hook, m); 428 } 429 return (error); 430 } 431 432 static int 433 ng_vlan_shutdown(node_p node) 434 { 435 const priv_p priv = NG_NODE_PRIVATE(node); 436 437 NG_NODE_SET_PRIVATE(node, NULL); 438 NG_NODE_UNREF(node); 439 free(priv, M_NETGRAPH); 440 return (0); 441 } 442 443 static int 444 ng_vlan_disconnect(hook_p hook) 445 { 446 const priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook)); 447 struct filter *f; 448 449 if (hook == priv->downstream_hook) 450 priv->downstream_hook = NULL; 451 else if (hook == priv->nomatch_hook) 452 priv->nomatch_hook = NULL; 453 else { 454 /* Purge a rule that refers to this hook. */ 455 if ((f = NG_HOOK_PRIVATE(hook)) != NULL) { 456 LIST_REMOVE(f, next); 457 priv->nent--; 458 free(f, M_NETGRAPH); 459 } 460 } 461 NG_HOOK_SET_PRIVATE(hook, NULL); 462 if ((NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0) && 463 (NG_NODE_IS_VALID(NG_HOOK_NODE(hook)))) 464 ng_rmnode_self(NG_HOOK_NODE(hook)); 465 return (0); 466 } 467