ng_gif.c revision 126203
1/* 2 * ng_gif.c 3 * 4 * Copyright 2001 The Aerospace Corporation. All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions, and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions, and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. The name of The Aerospace Corporation may not be used to endorse or 16 * promote products derived from this software. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE AEROSPACE CORPORATION ``AS IS'' AND 19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21 * ARE DISCLAIMED. IN NO EVENT SHALL THE AEROSPACE CORPORATION BE LIABLE 22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28 * SUCH DAMAGE. 29 * 30 * 31 * Copyright (c) 1996-2000 Whistle Communications, Inc. 32 * All rights reserved. 33 * 34 * Subject to the following obligations and disclaimer of warranty, use and 35 * redistribution of this software, in source or object code forms, with or 36 * without modifications are expressly permitted by Whistle Communications; 37 * provided, however, that: 38 * 1. Any and all reproductions of the source or object code must include the 39 * copyright notice above and the following disclaimer of warranties; and 40 * 2. No rights are granted, in any manner or form, to use Whistle 41 * Communications, Inc. trademarks, including the mark "WHISTLE 42 * COMMUNICATIONS" on advertising, endorsements, or otherwise except as 43 * such appears in the above copyright notice or in the software. 44 * 45 * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND 46 * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO 47 * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE, 48 * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF 49 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT. 50 * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY 51 * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS 52 * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE. 53 * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES 54 * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING 55 * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, 56 * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR 57 * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY 58 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 59 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 60 * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY 61 * OF SUCH DAMAGE. 62 * 63 * $FreeBSD: head/sys/netgraph/ng_gif.c 126203 2004-02-24 22:16:40Z phk $ 64 */ 65 66/* 67 * ng_gif(4) netgraph node type 68 */ 69 70#include <sys/param.h> 71#include <sys/systm.h> 72#include <sys/kernel.h> 73#include <sys/malloc.h> 74#include <sys/mbuf.h> 75#include <sys/errno.h> 76#include <sys/syslog.h> 77#include <sys/socket.h> 78 79#include <net/if.h> 80#include <net/route.h> 81#include <net/if_types.h> 82#include <net/if_var.h> 83#include <net/if_gif.h> 84 85#include <netgraph/ng_message.h> 86#include <netgraph/netgraph.h> 87#include <netgraph/ng_parse.h> 88#include <netgraph/ng_gif.h> 89 90#define IFP2NG(ifp) ((struct ng_node *)((struct gif_softc *)(ifp))->gif_netgraph) 91 92/* Per-node private data */ 93struct private { 94 struct ifnet *ifp; /* associated interface */ 95 hook_p lower; /* lower OR orphan hook connection */ 96 u_char lowerOrphan; /* whether lower is lower or orphan */ 97}; 98typedef struct private *priv_p; 99 100/* Functional hooks called from if_gif.c */ 101static void ng_gif_input(struct ifnet *ifp, struct mbuf **mp, int af); 102static void ng_gif_input_orphan(struct ifnet *ifp, struct mbuf *m, int af); 103static void ng_gif_attach(struct ifnet *ifp); 104static void ng_gif_detach(struct ifnet *ifp); 105 106/* Other functions */ 107static void ng_gif_input2(node_p node, struct mbuf **mp, int af); 108static int ng_gif_glue_af(struct mbuf **mp, int af); 109static int ng_gif_rcv_lower(node_p node, struct mbuf *m, meta_p meta); 110 111/* Netgraph node methods */ 112static ng_constructor_t ng_gif_constructor; 113static ng_rcvmsg_t ng_gif_rcvmsg; 114static ng_shutdown_t ng_gif_shutdown; 115static ng_newhook_t ng_gif_newhook; 116static ng_connect_t ng_gif_connect; 117static ng_rcvdata_t ng_gif_rcvdata; 118static ng_disconnect_t ng_gif_disconnect; 119static int ng_gif_mod_event(module_t mod, int event, void *data); 120 121/* List of commands and how to convert arguments to/from ASCII */ 122static const struct ng_cmdlist ng_gif_cmdlist[] = { 123 { 124 NGM_GIF_COOKIE, 125 NGM_GIF_GET_IFNAME, 126 "getifname", 127 NULL, 128 &ng_parse_string_type 129 }, 130 { 131 NGM_GIF_COOKIE, 132 NGM_GIF_GET_IFINDEX, 133 "getifindex", 134 NULL, 135 &ng_parse_int32_type 136 }, 137 { 0 } 138}; 139 140static struct ng_type ng_gif_typestruct = { 141 NG_ABI_VERSION, 142 NG_GIF_NODE_TYPE, 143 ng_gif_mod_event, 144 ng_gif_constructor, 145 ng_gif_rcvmsg, 146 ng_gif_shutdown, 147 ng_gif_newhook, 148 NULL, 149 ng_gif_connect, 150 ng_gif_rcvdata, 151 ng_gif_disconnect, 152 ng_gif_cmdlist, 153}; 154MODULE_VERSION(ng_gif, 1); 155MODULE_DEPEND(ng_gif, if_gif, 1,1,1); 156NETGRAPH_INIT(gif, &ng_gif_typestruct); 157 158/****************************************************************** 159 GIF FUNCTION HOOKS 160******************************************************************/ 161 162/* 163 * Handle a packet that has come in on an interface. We get to 164 * look at it here before any upper layer protocols do. 165 * 166 * NOTE: this function will get called at splimp() 167 */ 168static void 169ng_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 * NOTE: this function will get called at splimp() 185 */ 186static void 187ng_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 * NOTE: this function will get called at splimp() 207 */ 208static void 209ng_gif_input2(node_p node, struct mbuf **mp, int af) 210{ 211 const priv_p priv = NG_NODE_PRIVATE(node); 212 int error; 213 214 /* Glue address family on */ 215 if ((error = ng_gif_glue_af(mp, af)) != 0) 216 return; 217 218 /* Send out lower/orphan hook */ 219 NG_SEND_DATA_ONLY(error, priv->lower, *mp); 220 *mp = NULL; 221} 222 223/* 224 * A new gif interface has been attached. 225 * Create a new node for it, etc. 226 */ 227static void 228ng_gif_attach(struct ifnet *ifp) 229{ 230 priv_p priv; 231 node_p node; 232 233 /* Create node */ 234 KASSERT(!IFP2NG(ifp), ("%s: node already exists?", __func__)); 235 if (ng_make_node_common(&ng_gif_typestruct, &node) != 0) { 236 log(LOG_ERR, "%s: can't %s for %s\n", 237 __func__, "create node", ifp->if_xname); 238 return; 239 } 240 241 /* Allocate private data */ 242 MALLOC(priv, priv_p, sizeof(*priv), M_NETGRAPH, M_NOWAIT | M_ZERO); 243 if (priv == NULL) { 244 log(LOG_ERR, "%s: can't %s for %s\n", 245 __func__, "allocate memory", ifp->if_xname); 246 NG_NODE_UNREF(node); 247 return; 248 } 249 NG_NODE_SET_PRIVATE(node, priv); 250 priv->ifp = ifp; 251 IFP2NG(ifp) = node; 252 253 /* Try to give the node the same name as the interface */ 254 if (ng_name_node(node, ifp->if_xname) != 0) { 255 log(LOG_WARNING, "%s: can't name node %s\n", 256 __func__, ifp->if_xname); 257 } 258} 259 260/* 261 * An interface is being detached. 262 * REALLY Destroy its node. 263 */ 264static void 265ng_gif_detach(struct ifnet *ifp) 266{ 267 const node_p node = IFP2NG(ifp); 268 priv_p priv; 269 270 if (node == NULL) /* no node (why not?), ignore */ 271 return; 272 priv = NG_NODE_PRIVATE(node); 273 NG_NODE_REALLY_DIE(node); /* Force real removal of node */ 274 /* 275 * We can't assume the ifnet is still around when we run shutdown 276 * So zap it now. XXX We HOPE that anything running at this time 277 * handles it (as it should in the non netgraph case). 278 */ 279 IFP2NG(ifp) = NULL; 280 priv->ifp = NULL; /* XXX race if interrupted an output packet */ 281 ng_rmnode_self(node); /* remove all netgraph parts */ 282} 283 284/* 285 * Optimization for gluing the address family onto 286 * the front of an incoming packet. 287 */ 288static int 289ng_gif_glue_af(struct mbuf **mp, int af) 290{ 291 struct mbuf *m = *mp; 292 int error = 0; 293 sa_family_t tmp_af; 294 295 tmp_af = (sa_family_t) af; 296 297 /* 298 * XXX: should try to bring back some of the optimizations from 299 * ng_ether.c 300 */ 301 302 /* 303 * Doing anything more is likely to get more 304 * expensive than it's worth.. 305 * it's probable that everything else is in one 306 * big lump. The next node will do an m_pullup() 307 * for exactly the amount of data it needs and 308 * hopefully everything after that will not 309 * need one. So let's just use M_PREPEND. 310 */ 311 M_PREPEND(m, sizeof (tmp_af), M_DONTWAIT); 312 if (m == NULL) { 313 error = ENOBUFS; 314 goto done; 315 } 316 317#if 0 318copy: 319#endif 320 /* Copy header and return (possibly new) mbuf */ 321 *mtod(m, sa_family_t *) = tmp_af; 322#if 0 323 bcopy((caddr_t)&tmp_af, mtod(m, sa_family_t *), sizeof(tmp_af)); 324#endif 325done: 326 *mp = m; 327 return error; 328} 329 330/****************************************************************** 331 NETGRAPH NODE METHODS 332******************************************************************/ 333 334/* 335 * It is not possible or allowable to create a node of this type. 336 * Nodes get created when the interface is attached (or, when 337 * this node type's KLD is loaded). 338 */ 339static int 340ng_gif_constructor(node_p node) 341{ 342 return (EINVAL); 343} 344 345/* 346 * Check for attaching a new hook. 347 */ 348static int 349ng_gif_newhook(node_p node, hook_p hook, const char *name) 350{ 351 const priv_p priv = NG_NODE_PRIVATE(node); 352 u_char orphan = priv->lowerOrphan; 353 hook_p *hookptr; 354 355 /* Divert hook is an alias for lower */ 356 if (strcmp(name, NG_GIF_HOOK_DIVERT) == 0) 357 name = NG_GIF_HOOK_LOWER; 358 359 /* Which hook? */ 360 if (strcmp(name, NG_GIF_HOOK_LOWER) == 0) { 361 hookptr = &priv->lower; 362 orphan = 0; 363 } else if (strcmp(name, NG_GIF_HOOK_ORPHAN) == 0) { 364 hookptr = &priv->lower; 365 orphan = 1; 366 } else 367 return (EINVAL); 368 369 /* Check if already connected (shouldn't be, but doesn't hurt) */ 370 if (*hookptr != NULL) 371 return (EISCONN); 372 373 /* OK */ 374 *hookptr = hook; 375 priv->lowerOrphan = orphan; 376 return (0); 377} 378 379/* 380 * Hooks are attached, adjust to force queueing. 381 * We don't really care which hook it is. 382 * they should all be queuing for outgoing data. 383 */ 384static int 385ng_gif_connect(hook_p hook) 386{ 387 NG_HOOK_FORCE_QUEUE(NG_HOOK_PEER(hook)); 388 return (0); 389} 390 391/* 392 * Receive an incoming control message. 393 */ 394static int 395ng_gif_rcvmsg(node_p node, item_p item, hook_p lasthook) 396{ 397 const priv_p priv = NG_NODE_PRIVATE(node); 398 struct ng_mesg *resp = NULL; 399 int error = 0; 400 struct ng_mesg *msg; 401 402 NGI_GET_MSG(item, msg); 403 switch (msg->header.typecookie) { 404 case NGM_GIF_COOKIE: 405 switch (msg->header.cmd) { 406 case NGM_GIF_GET_IFNAME: 407 NG_MKRESPONSE(resp, msg, IFNAMSIZ + 1, M_NOWAIT); 408 if (resp == NULL) { 409 error = ENOMEM; 410 break; 411 } 412 strlcpy(resp->data, priv->ifp->if_xname, IFNAMSIZ + 1); 413 break; 414 case NGM_GIF_GET_IFINDEX: 415 NG_MKRESPONSE(resp, msg, sizeof(u_int32_t), M_NOWAIT); 416 if (resp == NULL) { 417 error = ENOMEM; 418 break; 419 } 420 *((u_int32_t *)resp->data) = priv->ifp->if_index; 421 break; 422 default: 423 error = EINVAL; 424 break; 425 } 426 break; 427 default: 428 error = EINVAL; 429 break; 430 } 431 NG_RESPOND_MSG(error, node, item, resp); 432 NG_FREE_MSG(msg); 433 return (error); 434} 435 436/* 437 * Receive data on a hook. 438 */ 439static int 440ng_gif_rcvdata(hook_p hook, item_p item) 441{ 442 const node_p node = NG_HOOK_NODE(hook); 443 const priv_p priv = NG_NODE_PRIVATE(node); 444 struct mbuf *m; 445 meta_p meta; 446 447 NGI_GET_M(item, m); 448 NGI_GET_META(item, meta); 449 NG_FREE_ITEM(item); 450 if (hook == priv->lower) 451 return ng_gif_rcv_lower(node, m, meta); 452 panic("%s: weird hook", __func__); 453} 454 455/* 456 * Handle an mbuf received on the "lower" hook. 457 */ 458static int 459ng_gif_rcv_lower(node_p node, struct mbuf *m, meta_p meta) 460{ 461 struct sockaddr dst; 462 const priv_p priv = NG_NODE_PRIVATE(node); 463 464 bzero(&dst, sizeof(dst)); 465 466 /* We don't process metadata. */ 467 NG_FREE_META(meta); 468 469 /* Make sure header is fully pulled up */ 470 if (m->m_pkthdr.len < sizeof(sa_family_t)) { 471 NG_FREE_M(m); 472 return (EINVAL); 473 } 474 if (m->m_len < sizeof(sa_family_t) 475 && (m = m_pullup(m, sizeof(sa_family_t))) == NULL) { 476 return (ENOBUFS); 477 } 478 479 dst.sa_family = *mtod(m, sa_family_t *); 480 m_adj(m, sizeof(sa_family_t)); 481 482 /* Send it on its way */ 483 /* 484 * XXX: gif_output only uses dst for the family and passes the 485 * fourth argument (rt) to in{,6}_gif_output which ignore it. 486 * If this changes ng_gif will probably break. 487 */ 488 return gif_output(priv->ifp, m, &dst, NULL); 489} 490 491/* 492 * Shutdown node. This resets the node but does not remove it 493 * unless the REALLY_DIE flag is set. 494 */ 495static int 496ng_gif_shutdown(node_p node) 497{ 498 const priv_p priv = NG_NODE_PRIVATE(node); 499 500 if (node->nd_flags & NG_REALLY_DIE) { 501 /* 502 * WE came here because the gif interface is being destroyed, 503 * so stop being persistant. 504 * Actually undo all the things we did on creation. 505 * Assume the ifp has already been freed. 506 */ 507 NG_NODE_SET_PRIVATE(node, NULL); 508 FREE(priv, M_NETGRAPH); 509 NG_NODE_UNREF(node); /* free node itself */ 510 return (0); 511 } 512 node->nd_flags &= ~NG_INVALID; /* Signal ng_rmnode we are persisant */ 513 return (0); 514} 515 516/* 517 * Hook disconnection. 518 */ 519static int 520ng_gif_disconnect(hook_p hook) 521{ 522 const priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook)); 523 524 if (hook == priv->lower) { 525 priv->lower = NULL; 526 priv->lowerOrphan = 0; 527 } else 528 panic("%s: weird hook", __func__); 529 if ((NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0) 530 && (NG_NODE_IS_VALID(NG_HOOK_NODE(hook)))) 531 ng_rmnode_self(NG_HOOK_NODE(hook)); /* reset node */ 532 533 return (0); 534} 535 536/****************************************************************** 537 INITIALIZATION 538******************************************************************/ 539 540/* 541 * Handle loading and unloading for this node type. 542 */ 543static int 544ng_gif_mod_event(module_t mod, int event, void *data) 545{ 546 struct ifnet *ifp; 547 int error = 0; 548 int s; 549 550 s = splnet(); 551 switch (event) { 552 case MOD_LOAD: 553 554 /* Register function hooks */ 555 if (ng_gif_attach_p != NULL) { 556 error = EEXIST; 557 break; 558 } 559 ng_gif_attach_p = ng_gif_attach; 560 ng_gif_detach_p = ng_gif_detach; 561 ng_gif_input_p = ng_gif_input; 562 ng_gif_input_orphan_p = ng_gif_input_orphan; 563 564 /* Create nodes for any already-existing gif interfaces */ 565 IFNET_RLOCK(); 566 TAILQ_FOREACH(ifp, &ifnet, if_link) { 567 if (ifp->if_type == IFT_GIF) 568 ng_gif_attach(ifp); 569 } 570 IFNET_RUNLOCK(); 571 break; 572 573 case MOD_UNLOAD: 574 575 /* 576 * Note that the base code won't try to unload us until 577 * all nodes have been removed, and that can't happen 578 * until all gif interfaces are destroyed. In any 579 * case, we know there are no nodes left if the action 580 * is MOD_UNLOAD, so there's no need to detach any nodes. 581 * 582 * XXX: what about manual unloads?!? 583 */ 584 585 /* Unregister function hooks */ 586 ng_gif_attach_p = NULL; 587 ng_gif_detach_p = NULL; 588 ng_gif_input_p = NULL; 589 ng_gif_input_orphan_p = NULL; 590 break; 591 592 default: 593 error = EOPNOTSUPP; 594 break; 595 } 596 splx(s); 597 return (error); 598} 599 600