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 * $FreeBSD$ 68 */ 69 70 /* 71 * ng_gif(4) netgraph node type 72 */ 73 #include <sys/param.h> 74 #include <sys/systm.h> 75 #include <sys/kernel.h> 76 #include <sys/malloc.h> 77 #include <sys/mbuf.h> 78 #include <sys/errno.h> 79 #include <sys/syslog.h> 80 #include <sys/socket.h> 81 82 #include <net/if.h> 83 #include <net/route.h> 84 #include <net/if_types.h> 85 #include <net/if_var.h> 86 #include <net/if_gif.h> 87 #include <net/if_private.h> 88 #include <net/vnet.h> 89 90 #include <netgraph/ng_message.h> 91 #include <netgraph/netgraph.h> 92 #include <netgraph/ng_parse.h> 93 #include <netgraph/ng_gif.h> 94 95 #define IFP2NG(ifp) ((struct ng_node *)((struct gif_softc *)(ifp->if_softc))->gif_netgraph) 96 #define IFP2NG_SET(ifp, val) (((struct gif_softc *)(ifp->if_softc))->gif_netgraph = (val)) 97 98 /* Per-node private data */ 99 struct private { 100 struct ifnet *ifp; /* associated interface */ 101 hook_p lower; /* lower OR orphan hook connection */ 102 u_char lowerOrphan; /* whether lower is lower or orphan */ 103 }; 104 typedef struct private *priv_p; 105 106 /* Functional hooks called from if_gif.c */ 107 static void ng_gif_input(struct ifnet *ifp, struct mbuf **mp, int af); 108 static void ng_gif_input_orphan(struct ifnet *ifp, struct mbuf *m, int af); 109 static void ng_gif_attach(struct ifnet *ifp); 110 static void ng_gif_detach(struct ifnet *ifp); 111 112 /* Other functions */ 113 static void ng_gif_input2(node_p node, struct mbuf **mp, int af); 114 static int ng_gif_glue_af(struct mbuf **mp, int af); 115 static int ng_gif_rcv_lower(node_p node, struct mbuf *m); 116 117 /* Netgraph node methods */ 118 static ng_constructor_t ng_gif_constructor; 119 static ng_rcvmsg_t ng_gif_rcvmsg; 120 static ng_shutdown_t ng_gif_shutdown; 121 static ng_newhook_t ng_gif_newhook; 122 static ng_connect_t ng_gif_connect; 123 static ng_rcvdata_t ng_gif_rcvdata; 124 static ng_disconnect_t ng_gif_disconnect; 125 static int ng_gif_mod_event(module_t mod, int event, void *data); 126 127 /* List of commands and how to convert arguments to/from ASCII */ 128 static const struct ng_cmdlist ng_gif_cmdlist[] = { 129 { 130 NGM_GIF_COOKIE, 131 NGM_GIF_GET_IFNAME, 132 "getifname", 133 NULL, 134 &ng_parse_string_type 135 }, 136 { 137 NGM_GIF_COOKIE, 138 NGM_GIF_GET_IFINDEX, 139 "getifindex", 140 NULL, 141 &ng_parse_int32_type 142 }, 143 { 0 } 144 }; 145 146 static struct ng_type ng_gif_typestruct = { 147 .version = NG_ABI_VERSION, 148 .name = NG_GIF_NODE_TYPE, 149 .mod_event = ng_gif_mod_event, 150 .constructor = ng_gif_constructor, 151 .rcvmsg = ng_gif_rcvmsg, 152 .shutdown = ng_gif_shutdown, 153 .newhook = ng_gif_newhook, 154 .connect = ng_gif_connect, 155 .rcvdata = ng_gif_rcvdata, 156 .disconnect = ng_gif_disconnect, 157 .cmdlist = ng_gif_cmdlist, 158 }; 159 MODULE_DEPEND(ng_gif, if_gif, 1,1,1); 160 NETGRAPH_INIT(gif, &ng_gif_typestruct); 161 162 /****************************************************************** 163 GIF FUNCTION HOOKS 164 ******************************************************************/ 165 166 /* 167 * Handle a packet that has come in on an interface. We get to 168 * look at it here before any upper layer protocols do. 169 */ 170 static void 171 ng_gif_input(struct ifnet *ifp, struct mbuf **mp, int af) 172 { 173 const node_p node = IFP2NG(ifp); 174 const priv_p priv = NG_NODE_PRIVATE(node); 175 176 /* If "lower" hook not connected, let packet continue */ 177 if (priv->lower == NULL || priv->lowerOrphan) 178 return; 179 ng_gif_input2(node, mp, af); 180 } 181 182 /* 183 * Handle a packet that has come in on an interface, and which 184 * does not match any of our known protocols (an ``orphan''). 185 */ 186 static void 187 ng_gif_input_orphan(struct ifnet *ifp, struct mbuf *m, int af) 188 { 189 const node_p node = IFP2NG(ifp); 190 const priv_p priv = NG_NODE_PRIVATE(node); 191 192 /* If "orphan" hook not connected, let packet continue */ 193 if (priv->lower == NULL || !priv->lowerOrphan) { 194 m_freem(m); 195 return; 196 } 197 ng_gif_input2(node, &m, af); 198 if (m != NULL) 199 m_freem(m); 200 } 201 202 /* 203 * Handle a packet that has come in on a gif interface. 204 * Attach the address family to the mbuf for later use. 205 */ 206 static void 207 ng_gif_input2(node_p node, struct mbuf **mp, int af) 208 { 209 const priv_p priv = NG_NODE_PRIVATE(node); 210 int error; 211 212 /* Glue address family on */ 213 if ((error = ng_gif_glue_af(mp, af)) != 0) 214 return; 215 216 /* Send out lower/orphan hook */ 217 NG_SEND_DATA_ONLY(error, priv->lower, *mp); 218 *mp = NULL; 219 } 220 221 /* 222 * A new gif interface has been attached. 223 * Create a new node for it, etc. 224 */ 225 static void 226 ng_gif_attach(struct ifnet *ifp) 227 { 228 priv_p priv; 229 node_p node; 230 231 /* Create node */ 232 KASSERT(!IFP2NG(ifp), ("%s: node already exists?", __func__)); 233 if (ng_make_node_common(&ng_gif_typestruct, &node) != 0) { 234 log(LOG_ERR, "%s: can't %s for %s\n", 235 __func__, "create node", ifp->if_xname); 236 return; 237 } 238 239 /* Allocate private data */ 240 priv = malloc(sizeof(*priv), M_NETGRAPH, M_NOWAIT | M_ZERO); 241 if (priv == NULL) { 242 log(LOG_ERR, "%s: can't %s for %s\n", 243 __func__, "allocate memory", ifp->if_xname); 244 NG_NODE_UNREF(node); 245 return; 246 } 247 NG_NODE_SET_PRIVATE(node, priv); 248 priv->ifp = ifp; 249 IFP2NG_SET(ifp, node); 250 251 /* Try to give the node the same name as the interface */ 252 if (ng_name_node(node, ifp->if_xname) != 0) { 253 log(LOG_WARNING, "%s: can't name node %s\n", 254 __func__, ifp->if_xname); 255 } 256 } 257 258 /* 259 * An interface is being detached. 260 * REALLY Destroy its node. 261 */ 262 static void 263 ng_gif_detach(struct ifnet *ifp) 264 { 265 const node_p node = IFP2NG(ifp); 266 priv_p priv; 267 268 if (node == NULL) /* no node (why not?), ignore */ 269 return; 270 priv = NG_NODE_PRIVATE(node); 271 NG_NODE_REALLY_DIE(node); /* Force real removal of node */ 272 /* 273 * We can't assume the ifnet is still around when we run shutdown 274 * So zap it now. XXX We HOPE that anything running at this time 275 * handles it (as it should in the non netgraph case). 276 */ 277 IFP2NG_SET(ifp, NULL); 278 priv->ifp = NULL; /* XXX race if interrupted an output packet */ 279 ng_rmnode_self(node); /* remove all netgraph parts */ 280 } 281 282 /* 283 * Optimization for gluing the address family onto 284 * the front of an incoming packet. 285 */ 286 static int 287 ng_gif_glue_af(struct mbuf **mp, int af) 288 { 289 struct mbuf *m = *mp; 290 int error = 0; 291 sa_family_t tmp_af; 292 293 tmp_af = (sa_family_t) af; 294 295 /* 296 * XXX: should try to bring back some of the optimizations from 297 * ng_ether.c 298 */ 299 300 /* 301 * Doing anything more is likely to get more 302 * expensive than it's worth.. 303 * it's probable that everything else is in one 304 * big lump. The next node will do an m_pullup() 305 * for exactly the amount of data it needs and 306 * hopefully everything after that will not 307 * need one. So let's just use M_PREPEND. 308 */ 309 M_PREPEND(m, sizeof (tmp_af), M_NOWAIT); 310 if (m == NULL) { 311 error = ENOBUFS; 312 goto done; 313 } 314 315 #if 0 316 copy: 317 #endif 318 /* Copy header and return (possibly new) mbuf */ 319 *mtod(m, sa_family_t *) = tmp_af; 320 #if 0 321 bcopy((caddr_t)&tmp_af, mtod(m, sa_family_t *), sizeof(tmp_af)); 322 #endif 323 done: 324 *mp = m; 325 return error; 326 } 327 328 /****************************************************************** 329 NETGRAPH NODE METHODS 330 ******************************************************************/ 331 332 /* 333 * It is not possible or allowable to create a node of this type. 334 * Nodes get created when the interface is attached (or, when 335 * this node type's KLD is loaded). 336 */ 337 static int 338 ng_gif_constructor(node_p node) 339 { 340 return (EINVAL); 341 } 342 343 /* 344 * Check for attaching a new hook. 345 */ 346 static int 347 ng_gif_newhook(node_p node, hook_p hook, const char *name) 348 { 349 const priv_p priv = NG_NODE_PRIVATE(node); 350 u_char orphan = priv->lowerOrphan; 351 hook_p *hookptr; 352 353 /* Divert hook is an alias for lower */ 354 if (strcmp(name, NG_GIF_HOOK_DIVERT) == 0) 355 name = NG_GIF_HOOK_LOWER; 356 357 /* Which hook? */ 358 if (strcmp(name, NG_GIF_HOOK_LOWER) == 0) { 359 hookptr = &priv->lower; 360 orphan = 0; 361 } else if (strcmp(name, NG_GIF_HOOK_ORPHAN) == 0) { 362 hookptr = &priv->lower; 363 orphan = 1; 364 } else 365 return (EINVAL); 366 367 /* Check if already connected (shouldn't be, but doesn't hurt) */ 368 if (*hookptr != NULL) 369 return (EISCONN); 370 371 /* OK */ 372 *hookptr = hook; 373 priv->lowerOrphan = orphan; 374 return (0); 375 } 376 377 /* 378 * Hooks are attached, adjust to force queueing. 379 * We don't really care which hook it is. 380 * they should all be queuing for outgoing data. 381 */ 382 static int 383 ng_gif_connect(hook_p hook) 384 { 385 NG_HOOK_FORCE_QUEUE(NG_HOOK_PEER(hook)); 386 return (0); 387 } 388 389 /* 390 * Receive an incoming control message. 391 */ 392 static int 393 ng_gif_rcvmsg(node_p node, item_p item, hook_p lasthook) 394 { 395 const priv_p priv = NG_NODE_PRIVATE(node); 396 struct ng_mesg *resp = NULL; 397 int error = 0; 398 struct ng_mesg *msg; 399 400 NGI_GET_MSG(item, msg); 401 switch (msg->header.typecookie) { 402 case NGM_GIF_COOKIE: 403 switch (msg->header.cmd) { 404 case NGM_GIF_GET_IFNAME: 405 NG_MKRESPONSE(resp, msg, IFNAMSIZ, M_NOWAIT); 406 if (resp == NULL) { 407 error = ENOMEM; 408 break; 409 } 410 strlcpy(resp->data, priv->ifp->if_xname, IFNAMSIZ); 411 break; 412 case NGM_GIF_GET_IFINDEX: 413 NG_MKRESPONSE(resp, msg, sizeof(u_int32_t), M_NOWAIT); 414 if (resp == NULL) { 415 error = ENOMEM; 416 break; 417 } 418 *((u_int32_t *)resp->data) = priv->ifp->if_index; 419 break; 420 default: 421 error = EINVAL; 422 break; 423 } 424 break; 425 default: 426 error = EINVAL; 427 break; 428 } 429 NG_RESPOND_MSG(error, node, item, resp); 430 NG_FREE_MSG(msg); 431 return (error); 432 } 433 434 /* 435 * Receive data on a hook. 436 */ 437 static int 438 ng_gif_rcvdata(hook_p hook, item_p item) 439 { 440 const node_p node = NG_HOOK_NODE(hook); 441 const priv_p priv = NG_NODE_PRIVATE(node); 442 struct mbuf *m; 443 444 NGI_GET_M(item, m); 445 NG_FREE_ITEM(item); 446 447 if (hook == priv->lower) 448 return ng_gif_rcv_lower(node, m); 449 panic("%s: weird hook", __func__); 450 } 451 452 /* 453 * Handle an mbuf received on the "lower" hook. 454 */ 455 static int 456 ng_gif_rcv_lower(node_p node, struct mbuf *m) 457 { 458 struct sockaddr dst; 459 const priv_p priv = NG_NODE_PRIVATE(node); 460 461 bzero(&dst, sizeof(dst)); 462 463 /* Make sure header is fully pulled up */ 464 if (m->m_pkthdr.len < sizeof(sa_family_t)) { 465 NG_FREE_M(m); 466 return (EINVAL); 467 } 468 if (m->m_len < sizeof(sa_family_t) 469 && (m = m_pullup(m, sizeof(sa_family_t))) == NULL) { 470 return (ENOBUFS); 471 } 472 473 dst.sa_family = *mtod(m, sa_family_t *); 474 m_adj(m, sizeof(sa_family_t)); 475 476 /* Send it on its way */ 477 /* 478 * XXX: gif_output only uses dst for the family and passes the 479 * fourth argument (rt) to in{,6}_gif_output which ignore it. 480 * If this changes ng_gif will probably break. 481 */ 482 return gif_output(priv->ifp, m, &dst, NULL); 483 } 484 485 /* 486 * Shutdown node. This resets the node but does not remove it 487 * unless the REALLY_DIE flag is set. 488 */ 489 static int 490 ng_gif_shutdown(node_p node) 491 { 492 const priv_p priv = NG_NODE_PRIVATE(node); 493 494 if (node->nd_flags & NGF_REALLY_DIE) { 495 /* 496 * WE came here because the gif interface is being destroyed, 497 * so stop being persistent. 498 * Actually undo all the things we did on creation. 499 * Assume the ifp has already been freed. 500 */ 501 NG_NODE_SET_PRIVATE(node, NULL); 502 free(priv, M_NETGRAPH); 503 NG_NODE_UNREF(node); /* free node itself */ 504 return (0); 505 } 506 NG_NODE_REVIVE(node); /* Signal ng_rmnode we are persisant */ 507 return (0); 508 } 509 510 /* 511 * Hook disconnection. 512 */ 513 static int 514 ng_gif_disconnect(hook_p hook) 515 { 516 const priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook)); 517 518 if (hook == priv->lower) { 519 priv->lower = NULL; 520 priv->lowerOrphan = 0; 521 } else 522 panic("%s: weird hook", __func__); 523 if ((NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0) 524 && (NG_NODE_IS_VALID(NG_HOOK_NODE(hook)))) 525 ng_rmnode_self(NG_HOOK_NODE(hook)); /* reset node */ 526 527 return (0); 528 } 529 530 /****************************************************************** 531 INITIALIZATION 532 ******************************************************************/ 533 534 /* 535 * Handle loading and unloading for this node type. 536 */ 537 static int 538 ng_gif_mod_event(module_t mod, int event, void *data) 539 { 540 VNET_ITERATOR_DECL(vnet_iter); 541 struct ifnet *ifp; 542 int error = 0; 543 544 switch (event) { 545 case MOD_LOAD: 546 547 /* Register function hooks */ 548 if (ng_gif_attach_p != NULL) { 549 error = EEXIST; 550 break; 551 } 552 ng_gif_attach_p = ng_gif_attach; 553 ng_gif_detach_p = ng_gif_detach; 554 ng_gif_input_p = ng_gif_input; 555 ng_gif_input_orphan_p = ng_gif_input_orphan; 556 557 /* Create nodes for any already-existing gif interfaces */ 558 VNET_LIST_RLOCK(); 559 IFNET_RLOCK(); 560 VNET_FOREACH(vnet_iter) { 561 CURVNET_SET_QUIET(vnet_iter); /* XXX revisit quiet */ 562 CK_STAILQ_FOREACH(ifp, &V_ifnet, if_link) { 563 if (ifp->if_type == IFT_GIF) 564 ng_gif_attach(ifp); 565 } 566 CURVNET_RESTORE(); 567 } 568 IFNET_RUNLOCK(); 569 VNET_LIST_RUNLOCK(); 570 break; 571 572 case MOD_UNLOAD: 573 574 /* 575 * Note that the base code won't try to unload us until 576 * all nodes have been removed, and that can't happen 577 * until all gif interfaces are destroyed. In any 578 * case, we know there are no nodes left if the action 579 * is MOD_UNLOAD, so there's no need to detach any nodes. 580 * 581 * XXX: what about manual unloads?!? 582 */ 583 584 /* Unregister function hooks */ 585 ng_gif_attach_p = NULL; 586 ng_gif_detach_p = NULL; 587 ng_gif_input_p = NULL; 588 ng_gif_input_orphan_p = NULL; 589 break; 590 591 default: 592 error = EOPNOTSUPP; 593 break; 594 } 595 return (error); 596 } 597