1 /* 2 * ng_gif.c 3 */ 4 5 /*- 6 * SPDX-License-Identifier: BSD-3-Clause AND BSD-2-Clause 7 * 8 * Copyright 2001 The Aerospace Corporation. All rights reserved. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions, and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions, and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. The name of The Aerospace Corporation may not be used to endorse or 20 * promote products derived from this software. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE AEROSPACE CORPORATION ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE AEROSPACE CORPORATION BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * 35 * Copyright (c) 1996-2000 Whistle Communications, Inc. 36 * All rights reserved. 37 * 38 * Subject to the following obligations and disclaimer of warranty, use and 39 * redistribution of this software, in source or object code forms, with or 40 * without modifications are expressly permitted by Whistle Communications; 41 * provided, however, that: 42 * 1. Any and all reproductions of the source or object code must include the 43 * copyright notice above and the following disclaimer of warranties; and 44 * 2. No rights are granted, in any manner or form, to use Whistle 45 * Communications, Inc. trademarks, including the mark "WHISTLE 46 * COMMUNICATIONS" on advertising, endorsements, or otherwise except as 47 * such appears in the above copyright notice or in the software. 48 * 49 * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND 50 * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO 51 * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE, 52 * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF 53 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT. 54 * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY 55 * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS 56 * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE. 57 * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES 58 * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING 59 * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, 60 * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR 61 * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY 62 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 63 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 64 * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY 65 * OF SUCH DAMAGE. 66 */ 67 68 /* 69 * ng_gif(4) netgraph node type 70 */ 71 #include <sys/param.h> 72 #include <sys/systm.h> 73 #include <sys/kernel.h> 74 #include <sys/malloc.h> 75 #include <sys/mbuf.h> 76 #include <sys/errno.h> 77 #include <sys/syslog.h> 78 #include <sys/socket.h> 79 80 #include <net/if.h> 81 #include <net/route.h> 82 #include <net/if_types.h> 83 #include <net/if_var.h> 84 #include <net/if_gif.h> 85 #include <net/if_private.h> 86 #include <net/vnet.h> 87 88 #include <netgraph/ng_message.h> 89 #include <netgraph/netgraph.h> 90 #include <netgraph/ng_parse.h> 91 #include <netgraph/ng_gif.h> 92 93 #define IFP2NG(ifp) ((struct ng_node *)((struct gif_softc *)(ifp->if_softc))->gif_netgraph) 94 #define IFP2NG_SET(ifp, val) (((struct gif_softc *)(ifp->if_softc))->gif_netgraph = (val)) 95 96 /* Per-node private data */ 97 struct private { 98 struct ifnet *ifp; /* associated interface */ 99 hook_p lower; /* lower OR orphan hook connection */ 100 u_char lowerOrphan; /* whether lower is lower or orphan */ 101 }; 102 typedef struct private *priv_p; 103 104 /* Functional hooks called from if_gif.c */ 105 static void ng_gif_input(struct ifnet *ifp, struct mbuf **mp, int af); 106 static void ng_gif_input_orphan(struct ifnet *ifp, struct mbuf *m, int af); 107 static void ng_gif_attach(struct ifnet *ifp); 108 static void ng_gif_detach(struct ifnet *ifp); 109 110 /* Other functions */ 111 static void ng_gif_input2(node_p node, struct mbuf **mp, int af); 112 static int ng_gif_glue_af(struct mbuf **mp, int af); 113 static int ng_gif_rcv_lower(node_p node, struct mbuf *m); 114 115 /* Netgraph node methods */ 116 static ng_constructor_t ng_gif_constructor; 117 static ng_rcvmsg_t ng_gif_rcvmsg; 118 static ng_shutdown_t ng_gif_shutdown; 119 static ng_newhook_t ng_gif_newhook; 120 static ng_connect_t ng_gif_connect; 121 static ng_rcvdata_t ng_gif_rcvdata; 122 static ng_disconnect_t ng_gif_disconnect; 123 static int ng_gif_mod_event(module_t mod, int event, void *data); 124 125 /* List of commands and how to convert arguments to/from ASCII */ 126 static const struct ng_cmdlist ng_gif_cmdlist[] = { 127 { 128 NGM_GIF_COOKIE, 129 NGM_GIF_GET_IFNAME, 130 "getifname", 131 NULL, 132 &ng_parse_string_type 133 }, 134 { 135 NGM_GIF_COOKIE, 136 NGM_GIF_GET_IFINDEX, 137 "getifindex", 138 NULL, 139 &ng_parse_int32_type 140 }, 141 { 0 } 142 }; 143 144 static struct ng_type ng_gif_typestruct = { 145 .version = NG_ABI_VERSION, 146 .name = NG_GIF_NODE_TYPE, 147 .mod_event = ng_gif_mod_event, 148 .constructor = ng_gif_constructor, 149 .rcvmsg = ng_gif_rcvmsg, 150 .shutdown = ng_gif_shutdown, 151 .newhook = ng_gif_newhook, 152 .connect = ng_gif_connect, 153 .rcvdata = ng_gif_rcvdata, 154 .disconnect = ng_gif_disconnect, 155 .cmdlist = ng_gif_cmdlist, 156 }; 157 MODULE_DEPEND(ng_gif, if_gif, 1,1,1); 158 NETGRAPH_INIT(gif, &ng_gif_typestruct); 159 160 /****************************************************************** 161 GIF FUNCTION HOOKS 162 ******************************************************************/ 163 164 /* 165 * Handle a packet that has come in on an interface. We get to 166 * look at it here before any upper layer protocols do. 167 */ 168 static void 169 ng_gif_input(struct ifnet *ifp, struct mbuf **mp, int af) 170 { 171 const node_p node = IFP2NG(ifp); 172 const priv_p priv = NG_NODE_PRIVATE(node); 173 174 /* If "lower" hook not connected, let packet continue */ 175 if (priv->lower == NULL || priv->lowerOrphan) 176 return; 177 ng_gif_input2(node, mp, af); 178 } 179 180 /* 181 * Handle a packet that has come in on an interface, and which 182 * does not match any of our known protocols (an ``orphan''). 183 */ 184 static void 185 ng_gif_input_orphan(struct ifnet *ifp, struct mbuf *m, int af) 186 { 187 const node_p node = IFP2NG(ifp); 188 const priv_p priv = NG_NODE_PRIVATE(node); 189 190 /* If "orphan" hook not connected, let packet continue */ 191 if (priv->lower == NULL || !priv->lowerOrphan) { 192 m_freem(m); 193 return; 194 } 195 ng_gif_input2(node, &m, af); 196 if (m != NULL) 197 m_freem(m); 198 } 199 200 /* 201 * Handle a packet that has come in on a gif interface. 202 * Attach the address family to the mbuf for later use. 203 */ 204 static void 205 ng_gif_input2(node_p node, struct mbuf **mp, int af) 206 { 207 const priv_p priv = NG_NODE_PRIVATE(node); 208 int error; 209 210 /* Glue address family on */ 211 if ((error = ng_gif_glue_af(mp, af)) != 0) 212 return; 213 214 /* Send out lower/orphan hook */ 215 NG_SEND_DATA_ONLY(error, priv->lower, *mp); 216 *mp = NULL; 217 } 218 219 /* 220 * A new gif interface has been attached. 221 * Create a new node for it, etc. 222 */ 223 static void 224 ng_gif_attach(struct ifnet *ifp) 225 { 226 priv_p priv; 227 node_p node; 228 229 /* Create node */ 230 KASSERT(!IFP2NG(ifp), ("%s: node already exists?", __func__)); 231 if (ng_make_node_common(&ng_gif_typestruct, &node) != 0) { 232 log(LOG_ERR, "%s: can't %s for %s\n", 233 __func__, "create node", ifp->if_xname); 234 return; 235 } 236 237 /* Allocate private data */ 238 priv = malloc(sizeof(*priv), M_NETGRAPH, M_NOWAIT | M_ZERO); 239 if (priv == NULL) { 240 log(LOG_ERR, "%s: can't %s for %s\n", 241 __func__, "allocate memory", ifp->if_xname); 242 NG_NODE_UNREF(node); 243 return; 244 } 245 NG_NODE_SET_PRIVATE(node, priv); 246 priv->ifp = ifp; 247 IFP2NG_SET(ifp, node); 248 249 /* Try to give the node the same name as the interface */ 250 if (ng_name_node(node, ifp->if_xname) != 0) { 251 log(LOG_WARNING, "%s: can't name node %s\n", 252 __func__, ifp->if_xname); 253 } 254 } 255 256 /* 257 * An interface is being detached. 258 * REALLY Destroy its node. 259 */ 260 static void 261 ng_gif_detach(struct ifnet *ifp) 262 { 263 const node_p node = IFP2NG(ifp); 264 priv_p priv; 265 266 if (node == NULL) /* no node (why not?), ignore */ 267 return; 268 priv = NG_NODE_PRIVATE(node); 269 NG_NODE_REALLY_DIE(node); /* Force real removal of node */ 270 /* 271 * We can't assume the ifnet is still around when we run shutdown 272 * So zap it now. XXX We HOPE that anything running at this time 273 * handles it (as it should in the non netgraph case). 274 */ 275 IFP2NG_SET(ifp, NULL); 276 priv->ifp = NULL; /* XXX race if interrupted an output packet */ 277 ng_rmnode_self(node); /* remove all netgraph parts */ 278 } 279 280 /* 281 * Optimization for gluing the address family onto 282 * the front of an incoming packet. 283 */ 284 static int 285 ng_gif_glue_af(struct mbuf **mp, int af) 286 { 287 struct mbuf *m = *mp; 288 int error = 0; 289 sa_family_t tmp_af; 290 291 tmp_af = (sa_family_t) af; 292 293 /* 294 * XXX: should try to bring back some of the optimizations from 295 * ng_ether.c 296 */ 297 298 /* 299 * Doing anything more is likely to get more 300 * expensive than it's worth.. 301 * it's probable that everything else is in one 302 * big lump. The next node will do an m_pullup() 303 * for exactly the amount of data it needs and 304 * hopefully everything after that will not 305 * need one. So let's just use M_PREPEND. 306 */ 307 M_PREPEND(m, sizeof (tmp_af), M_NOWAIT); 308 if (m == NULL) { 309 error = ENOBUFS; 310 goto done; 311 } 312 313 #if 0 314 copy: 315 #endif 316 /* Copy header and return (possibly new) mbuf */ 317 *mtod(m, sa_family_t *) = tmp_af; 318 #if 0 319 bcopy((caddr_t)&tmp_af, mtod(m, sa_family_t *), sizeof(tmp_af)); 320 #endif 321 done: 322 *mp = m; 323 return error; 324 } 325 326 /****************************************************************** 327 NETGRAPH NODE METHODS 328 ******************************************************************/ 329 330 /* 331 * It is not possible or allowable to create a node of this type. 332 * Nodes get created when the interface is attached (or, when 333 * this node type's KLD is loaded). 334 */ 335 static int 336 ng_gif_constructor(node_p node) 337 { 338 return (EINVAL); 339 } 340 341 /* 342 * Check for attaching a new hook. 343 */ 344 static int 345 ng_gif_newhook(node_p node, hook_p hook, const char *name) 346 { 347 const priv_p priv = NG_NODE_PRIVATE(node); 348 u_char orphan = priv->lowerOrphan; 349 hook_p *hookptr; 350 351 /* Divert hook is an alias for lower */ 352 if (strcmp(name, NG_GIF_HOOK_DIVERT) == 0) 353 name = NG_GIF_HOOK_LOWER; 354 355 /* Which hook? */ 356 if (strcmp(name, NG_GIF_HOOK_LOWER) == 0) { 357 hookptr = &priv->lower; 358 orphan = 0; 359 } else if (strcmp(name, NG_GIF_HOOK_ORPHAN) == 0) { 360 hookptr = &priv->lower; 361 orphan = 1; 362 } else 363 return (EINVAL); 364 365 /* Check if already connected (shouldn't be, but doesn't hurt) */ 366 if (*hookptr != NULL) 367 return (EISCONN); 368 369 /* OK */ 370 *hookptr = hook; 371 priv->lowerOrphan = orphan; 372 return (0); 373 } 374 375 /* 376 * Hooks are attached, adjust to force queueing. 377 * We don't really care which hook it is. 378 * they should all be queuing for outgoing data. 379 */ 380 static int 381 ng_gif_connect(hook_p hook) 382 { 383 NG_HOOK_FORCE_QUEUE(NG_HOOK_PEER(hook)); 384 return (0); 385 } 386 387 /* 388 * Receive an incoming control message. 389 */ 390 static int 391 ng_gif_rcvmsg(node_p node, item_p item, hook_p lasthook) 392 { 393 const priv_p priv = NG_NODE_PRIVATE(node); 394 struct ng_mesg *resp = NULL; 395 int error = 0; 396 struct ng_mesg *msg; 397 398 NGI_GET_MSG(item, msg); 399 switch (msg->header.typecookie) { 400 case NGM_GIF_COOKIE: 401 switch (msg->header.cmd) { 402 case NGM_GIF_GET_IFNAME: 403 NG_MKRESPONSE(resp, msg, IFNAMSIZ, M_NOWAIT); 404 if (resp == NULL) { 405 error = ENOMEM; 406 break; 407 } 408 strlcpy(resp->data, priv->ifp->if_xname, IFNAMSIZ); 409 break; 410 case NGM_GIF_GET_IFINDEX: 411 NG_MKRESPONSE(resp, msg, sizeof(u_int32_t), M_NOWAIT); 412 if (resp == NULL) { 413 error = ENOMEM; 414 break; 415 } 416 *((u_int32_t *)resp->data) = priv->ifp->if_index; 417 break; 418 default: 419 error = EINVAL; 420 break; 421 } 422 break; 423 default: 424 error = EINVAL; 425 break; 426 } 427 NG_RESPOND_MSG(error, node, item, resp); 428 NG_FREE_MSG(msg); 429 return (error); 430 } 431 432 /* 433 * Receive data on a hook. 434 */ 435 static int 436 ng_gif_rcvdata(hook_p hook, item_p item) 437 { 438 const node_p node = NG_HOOK_NODE(hook); 439 const priv_p priv = NG_NODE_PRIVATE(node); 440 struct mbuf *m; 441 442 NGI_GET_M(item, m); 443 NG_FREE_ITEM(item); 444 445 if (hook == priv->lower) 446 return ng_gif_rcv_lower(node, m); 447 panic("%s: weird hook", __func__); 448 } 449 450 /* 451 * Handle an mbuf received on the "lower" hook. 452 */ 453 static int 454 ng_gif_rcv_lower(node_p node, struct mbuf *m) 455 { 456 struct sockaddr dst; 457 const priv_p priv = NG_NODE_PRIVATE(node); 458 459 bzero(&dst, sizeof(dst)); 460 461 /* Make sure header is fully pulled up */ 462 if (m->m_pkthdr.len < sizeof(sa_family_t)) { 463 NG_FREE_M(m); 464 return (EINVAL); 465 } 466 if (m->m_len < sizeof(sa_family_t) 467 && (m = m_pullup(m, sizeof(sa_family_t))) == NULL) { 468 return (ENOBUFS); 469 } 470 471 dst.sa_family = *mtod(m, sa_family_t *); 472 m_adj(m, sizeof(sa_family_t)); 473 474 /* Send it on its way */ 475 /* 476 * XXX: gif_output only uses dst for the family and passes the 477 * fourth argument (rt) to in{,6}_gif_output which ignore it. 478 * If this changes ng_gif will probably break. 479 */ 480 return gif_output(priv->ifp, m, &dst, NULL); 481 } 482 483 /* 484 * Shutdown node. This resets the node but does not remove it 485 * unless the REALLY_DIE flag is set. 486 */ 487 static int 488 ng_gif_shutdown(node_p node) 489 { 490 const priv_p priv = NG_NODE_PRIVATE(node); 491 492 if (node->nd_flags & NGF_REALLY_DIE) { 493 /* 494 * WE came here because the gif interface is being destroyed, 495 * so stop being persistent. 496 * Actually undo all the things we did on creation. 497 * Assume the ifp has already been freed. 498 */ 499 NG_NODE_SET_PRIVATE(node, NULL); 500 free(priv, M_NETGRAPH); 501 NG_NODE_UNREF(node); /* free node itself */ 502 return (0); 503 } 504 NG_NODE_REVIVE(node); /* Signal ng_rmnode we are persisant */ 505 return (0); 506 } 507 508 /* 509 * Hook disconnection. 510 */ 511 static int 512 ng_gif_disconnect(hook_p hook) 513 { 514 const priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook)); 515 516 if (hook == priv->lower) { 517 priv->lower = NULL; 518 priv->lowerOrphan = 0; 519 } else 520 panic("%s: weird hook", __func__); 521 if ((NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0) 522 && (NG_NODE_IS_VALID(NG_HOOK_NODE(hook)))) 523 ng_rmnode_self(NG_HOOK_NODE(hook)); /* reset node */ 524 525 return (0); 526 } 527 528 /****************************************************************** 529 INITIALIZATION 530 ******************************************************************/ 531 532 /* 533 * Handle loading and unloading for this node type. 534 */ 535 static int 536 ng_gif_mod_event(module_t mod, int event, void *data) 537 { 538 VNET_ITERATOR_DECL(vnet_iter); 539 struct ifnet *ifp; 540 int error = 0; 541 542 switch (event) { 543 case MOD_LOAD: 544 545 /* Register function hooks */ 546 if (ng_gif_attach_p != NULL) { 547 error = EEXIST; 548 break; 549 } 550 ng_gif_attach_p = ng_gif_attach; 551 ng_gif_detach_p = ng_gif_detach; 552 ng_gif_input_p = ng_gif_input; 553 ng_gif_input_orphan_p = ng_gif_input_orphan; 554 555 /* Create nodes for any already-existing gif interfaces */ 556 VNET_LIST_RLOCK(); 557 IFNET_RLOCK(); 558 VNET_FOREACH(vnet_iter) { 559 CURVNET_SET_QUIET(vnet_iter); /* XXX revisit quiet */ 560 CK_STAILQ_FOREACH(ifp, &V_ifnet, if_link) { 561 if (ifp->if_type == IFT_GIF) 562 ng_gif_attach(ifp); 563 } 564 CURVNET_RESTORE(); 565 } 566 IFNET_RUNLOCK(); 567 VNET_LIST_RUNLOCK(); 568 break; 569 570 case MOD_UNLOAD: 571 572 /* 573 * Note that the base code won't try to unload us until 574 * all nodes have been removed, and that can't happen 575 * until all gif interfaces are destroyed. In any 576 * case, we know there are no nodes left if the action 577 * is MOD_UNLOAD, so there's no need to detach any nodes. 578 * 579 * XXX: what about manual unloads?!? 580 */ 581 582 /* Unregister function hooks */ 583 ng_gif_attach_p = NULL; 584 ng_gif_detach_p = NULL; 585 ng_gif_input_p = NULL; 586 ng_gif_input_orphan_p = NULL; 587 break; 588 589 default: 590 error = EOPNOTSUPP; 591 break; 592 } 593 return (error); 594 } 595