1 2 /* 3 * ng_base.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 * Authors: Julian Elischer <julian@whistle.com> 38 * Archie Cobbs <archie@whistle.com> 39 * 40 * $FreeBSD$ 41 * $Whistle: ng_base.c,v 1.39 1999/01/28 23:54:53 julian Exp $ 42 */ 43 44 /* 45 * This file implements the base netgraph code. 46 */ 47 48 #include <sys/param.h> 49 #include <sys/systm.h> 50 #include <sys/errno.h> 51 #include <sys/kernel.h> 52 #include <sys/malloc.h> 53 #include <sys/syslog.h> 54 #include <sys/linker.h> 55 #include <sys/queue.h> 56 #include <sys/mbuf.h> 57 #include <sys/ctype.h> 58 #include <machine/limits.h> 59 60 #include <net/netisr.h> 61 62 #include <netgraph/ng_message.h> 63 #include <netgraph/netgraph.h> 64 #include <netgraph/ng_parse.h> 65 66 /* List of all nodes */ 67 static LIST_HEAD(, ng_node) nodelist; 68 69 /* List of installed types */ 70 static LIST_HEAD(, ng_type) typelist; 71 72 /* Hash releted definitions */ 73 #define ID_HASH_SIZE 32 /* most systems wont need even this many */ 74 static LIST_HEAD(, ng_node) ID_hash[ID_HASH_SIZE]; 75 /* Don't nead to initialise them because it's a LIST */ 76 77 /* Internal functions */ 78 static int ng_add_hook(node_p node, const char *name, hook_p * hookp); 79 static int ng_connect(hook_p hook1, hook_p hook2); 80 static void ng_disconnect_hook(hook_p hook); 81 static int ng_generic_msg(node_p here, struct ng_mesg *msg, 82 const char *retaddr, struct ng_mesg ** resp); 83 static ng_ID_t ng_decodeidname(const char *name); 84 static int ngb_mod_event(module_t mod, int event, void *data); 85 static void ngintr(void); 86 87 /* Our own netgraph malloc type */ 88 MALLOC_DEFINE(M_NETGRAPH, "netgraph", "netgraph structures and ctrl messages"); 89 90 /* Set this to Debugger("X") to catch all errors as they occur */ 91 #ifndef TRAP_ERROR 92 #define TRAP_ERROR 93 #endif 94 95 static ng_ID_t nextID = 1; 96 97 #ifdef INVARIANTS 98 #define CHECK_DATA_MBUF(m) do { \ 99 struct mbuf *n; \ 100 int total; \ 101 \ 102 if (((m)->m_flags & M_PKTHDR) == 0) \ 103 panic("%s: !PKTHDR", __FUNCTION__); \ 104 for (total = 0, n = (m); n != NULL; n = n->m_next) \ 105 total += n->m_len; \ 106 if ((m)->m_pkthdr.len != total) { \ 107 panic("%s: %d != %d", \ 108 __FUNCTION__, (m)->m_pkthdr.len, total); \ 109 } \ 110 } while (0) 111 #else 112 #define CHECK_DATA_MBUF(m) 113 #endif 114 115 116 /************************************************************************ 117 Parse type definitions for generic messages 118 ************************************************************************/ 119 120 /* Handy structure parse type defining macro */ 121 #define DEFINE_PARSE_STRUCT_TYPE(lo, up, args) \ 122 static const struct ng_parse_struct_info \ 123 ng_ ## lo ## _type_info = NG_GENERIC_ ## up ## _INFO args; \ 124 static const struct ng_parse_type ng_generic_ ## lo ## _type = { \ 125 &ng_parse_struct_type, \ 126 &ng_ ## lo ## _type_info \ 127 } 128 129 DEFINE_PARSE_STRUCT_TYPE(mkpeer, MKPEER, ()); 130 DEFINE_PARSE_STRUCT_TYPE(connect, CONNECT, ()); 131 DEFINE_PARSE_STRUCT_TYPE(name, NAME, ()); 132 DEFINE_PARSE_STRUCT_TYPE(rmhook, RMHOOK, ()); 133 DEFINE_PARSE_STRUCT_TYPE(nodeinfo, NODEINFO, ()); 134 DEFINE_PARSE_STRUCT_TYPE(typeinfo, TYPEINFO, ()); 135 DEFINE_PARSE_STRUCT_TYPE(linkinfo, LINKINFO, (&ng_generic_nodeinfo_type)); 136 137 /* Get length of an array when the length is stored as a 32 bit 138 value immediately preceeding the array -- as with struct namelist 139 and struct typelist. */ 140 static int 141 ng_generic_list_getLength(const struct ng_parse_type *type, 142 const u_char *start, const u_char *buf) 143 { 144 return *((const u_int32_t *)(buf - 4)); 145 } 146 147 /* Get length of the array of struct linkinfo inside a struct hooklist */ 148 static int 149 ng_generic_linkinfo_getLength(const struct ng_parse_type *type, 150 const u_char *start, const u_char *buf) 151 { 152 const struct hooklist *hl = (const struct hooklist *)start; 153 154 return hl->nodeinfo.hooks; 155 } 156 157 /* Array type for a variable length array of struct namelist */ 158 static const struct ng_parse_array_info ng_nodeinfoarray_type_info = { 159 &ng_generic_nodeinfo_type, 160 &ng_generic_list_getLength 161 }; 162 static const struct ng_parse_type ng_generic_nodeinfoarray_type = { 163 &ng_parse_array_type, 164 &ng_nodeinfoarray_type_info 165 }; 166 167 /* Array type for a variable length array of struct typelist */ 168 static const struct ng_parse_array_info ng_typeinfoarray_type_info = { 169 &ng_generic_typeinfo_type, 170 &ng_generic_list_getLength 171 }; 172 static const struct ng_parse_type ng_generic_typeinfoarray_type = { 173 &ng_parse_array_type, 174 &ng_typeinfoarray_type_info 175 }; 176 177 /* Array type for array of struct linkinfo in struct hooklist */ 178 static const struct ng_parse_array_info ng_generic_linkinfo_array_type_info = { 179 &ng_generic_linkinfo_type, 180 &ng_generic_linkinfo_getLength 181 }; 182 static const struct ng_parse_type ng_generic_linkinfo_array_type = { 183 &ng_parse_array_type, 184 &ng_generic_linkinfo_array_type_info 185 }; 186 187 DEFINE_PARSE_STRUCT_TYPE(typelist, TYPELIST, (&ng_generic_nodeinfoarray_type)); 188 DEFINE_PARSE_STRUCT_TYPE(hooklist, HOOKLIST, 189 (&ng_generic_nodeinfo_type, &ng_generic_linkinfo_array_type)); 190 DEFINE_PARSE_STRUCT_TYPE(listnodes, LISTNODES, 191 (&ng_generic_nodeinfoarray_type)); 192 193 /* List of commands and how to convert arguments to/from ASCII */ 194 static const struct ng_cmdlist ng_generic_cmds[] = { 195 { 196 NGM_GENERIC_COOKIE, 197 NGM_SHUTDOWN, 198 "shutdown", 199 NULL, 200 NULL 201 }, 202 { 203 NGM_GENERIC_COOKIE, 204 NGM_MKPEER, 205 "mkpeer", 206 &ng_generic_mkpeer_type, 207 NULL 208 }, 209 { 210 NGM_GENERIC_COOKIE, 211 NGM_CONNECT, 212 "connect", 213 &ng_generic_connect_type, 214 NULL 215 }, 216 { 217 NGM_GENERIC_COOKIE, 218 NGM_NAME, 219 "name", 220 &ng_generic_name_type, 221 NULL 222 }, 223 { 224 NGM_GENERIC_COOKIE, 225 NGM_RMHOOK, 226 "rmhook", 227 &ng_generic_rmhook_type, 228 NULL 229 }, 230 { 231 NGM_GENERIC_COOKIE, 232 NGM_NODEINFO, 233 "nodeinfo", 234 NULL, 235 &ng_generic_nodeinfo_type 236 }, 237 { 238 NGM_GENERIC_COOKIE, 239 NGM_LISTHOOKS, 240 "listhooks", 241 NULL, 242 &ng_generic_hooklist_type 243 }, 244 { 245 NGM_GENERIC_COOKIE, 246 NGM_LISTNAMES, 247 "listnames", 248 NULL, 249 &ng_generic_listnodes_type /* same as NGM_LISTNODES */ 250 }, 251 { 252 NGM_GENERIC_COOKIE, 253 NGM_LISTNODES, 254 "listnodes", 255 NULL, 256 &ng_generic_listnodes_type 257 }, 258 { 259 NGM_GENERIC_COOKIE, 260 NGM_LISTTYPES, 261 "listtypes", 262 NULL, 263 &ng_generic_typeinfo_type 264 }, 265 { 266 NGM_GENERIC_COOKIE, 267 NGM_TEXT_STATUS, 268 "textstatus", 269 NULL, 270 &ng_parse_string_type 271 }, 272 { 273 NGM_GENERIC_COOKIE, 274 NGM_ASCII2BINARY, 275 "ascii2binary", 276 &ng_parse_ng_mesg_type, 277 &ng_parse_ng_mesg_type 278 }, 279 { 280 NGM_GENERIC_COOKIE, 281 NGM_BINARY2ASCII, 282 "binary2ascii", 283 &ng_parse_ng_mesg_type, 284 &ng_parse_ng_mesg_type 285 }, 286 { 0 } 287 }; 288 289 /************************************************************************ 290 Node routines 291 ************************************************************************/ 292 293 /* 294 * Instantiate a node of the requested type 295 */ 296 int 297 ng_make_node(const char *typename, node_p *nodepp) 298 { 299 struct ng_type *type; 300 301 /* Check that the type makes sense */ 302 if (typename == NULL) { 303 TRAP_ERROR; 304 return (EINVAL); 305 } 306 307 /* Locate the node type */ 308 if ((type = ng_findtype(typename)) == NULL) { 309 char *path, filename[NG_TYPELEN + 4]; 310 linker_file_t lf; 311 int error; 312 313 /* Not found, try to load it as a loadable module */ 314 snprintf(filename, sizeof(filename), "ng_%s.ko", typename); 315 if ((path = linker_search_path(filename)) == NULL) 316 return (ENXIO); 317 error = linker_load_file(path, &lf); 318 FREE(path, M_LINKER); 319 if (error != 0) 320 return (error); 321 lf->userrefs++; /* pretend loaded by the syscall */ 322 323 /* Try again, as now the type should have linked itself in */ 324 if ((type = ng_findtype(typename)) == NULL) 325 return (ENXIO); 326 } 327 328 /* Call the constructor */ 329 if (type->constructor != NULL) 330 return ((*type->constructor)(nodepp)); 331 else 332 return (ng_make_node_common(type, nodepp)); 333 } 334 335 /* 336 * Generic node creation. Called by node constructors. 337 * The returned node has a reference count of 1. 338 */ 339 int 340 ng_make_node_common(struct ng_type *type, node_p *nodepp) 341 { 342 node_p node; 343 344 /* Require the node type to have been already installed */ 345 if (ng_findtype(type->name) == NULL) { 346 TRAP_ERROR; 347 return (EINVAL); 348 } 349 350 /* Make a node and try attach it to the type */ 351 MALLOC(node, node_p, sizeof(*node), M_NETGRAPH, M_WAITOK); 352 if (node == NULL) { 353 TRAP_ERROR; 354 return (ENOMEM); 355 } 356 bzero(node, sizeof(*node)); 357 node->type = type; 358 node->refs++; /* note reference */ 359 type->refs++; 360 361 /* Link us into the node linked list */ 362 LIST_INSERT_HEAD(&nodelist, node, nodes); 363 364 /* Initialize hook list for new node */ 365 LIST_INIT(&node->hooks); 366 367 /* get an ID and put us in the hash chain */ 368 node->ID = nextID++; /* 137 per second for 1 year before wrap */ 369 LIST_INSERT_HEAD(&ID_hash[node->ID % ID_HASH_SIZE], node, idnodes); 370 371 /* Done */ 372 *nodepp = node; 373 return (0); 374 } 375 376 /* 377 * Forceably start the shutdown process on a node. Either call 378 * it's shutdown method, or do the default shutdown if there is 379 * no type-specific method. 380 * 381 * Persistent nodes must have a type-specific method which 382 * resets the NG_INVALID flag. 383 */ 384 void 385 ng_rmnode(node_p node) 386 { 387 /* Check if it's already shutting down */ 388 if ((node->flags & NG_INVALID) != 0) 389 return; 390 391 /* Add an extra reference so it doesn't go away during this */ 392 node->refs++; 393 394 /* Mark it invalid so any newcomers know not to try use it */ 395 node->flags |= NG_INVALID; 396 397 /* Ask the type if it has anything to do in this case */ 398 if (node->type && node->type->shutdown) 399 (*node->type->shutdown)(node); 400 else { /* do the default thing */ 401 ng_unname(node); 402 ng_cutlinks(node); 403 ng_unref(node); 404 } 405 406 /* Remove extra reference, possibly the last */ 407 ng_unref(node); 408 } 409 410 /* 411 * Called by the destructor to remove any STANDARD external references 412 */ 413 void 414 ng_cutlinks(node_p node) 415 { 416 hook_p hook; 417 418 /* Make sure that this is set to stop infinite loops */ 419 node->flags |= NG_INVALID; 420 421 /* If we have sleepers, wake them up; they'll see NG_INVALID */ 422 if (node->sleepers) 423 wakeup(node); 424 425 /* Notify all remaining connected nodes to disconnect */ 426 while ((hook = LIST_FIRST(&node->hooks)) != NULL) 427 ng_destroy_hook(hook); 428 } 429 430 /* 431 * Remove a reference to the node, possibly the last 432 */ 433 void 434 ng_unref(node_p node) 435 { 436 if (--node->refs <= 0) { 437 node->type->refs--; 438 LIST_REMOVE(node, nodes); 439 LIST_REMOVE(node, idnodes); 440 FREE(node, M_NETGRAPH); 441 } 442 } 443 444 /* 445 * Wait for a node to come ready. Returns a node with a reference count; 446 * don't forget to drop it when we are done with it using ng_release_node(). 447 */ 448 int 449 ng_wait_node(node_p node, char *msg) 450 { 451 int s, error = 0; 452 453 if (msg == NULL) 454 msg = "netgraph"; 455 s = splnet(); 456 node->sleepers++; 457 node->refs++; /* the sleeping process counts as a reference */ 458 while ((node->flags & (NG_BUSY | NG_INVALID)) == NG_BUSY) 459 error = tsleep(node, (PZERO + 1) | PCATCH, msg, 0); 460 node->sleepers--; 461 if (node->flags & NG_INVALID) { 462 TRAP_ERROR; 463 error = ENXIO; 464 } else { 465 KASSERT(node->refs > 1, 466 ("%s: refs=%d", __FUNCTION__, node->refs)); 467 node->flags |= NG_BUSY; 468 } 469 splx(s); 470 471 /* Release the reference we had on it */ 472 if (error != 0) 473 ng_unref(node); 474 return error; 475 } 476 477 /* 478 * Release a node acquired via ng_wait_node() 479 */ 480 void 481 ng_release_node(node_p node) 482 { 483 /* Declare that we don't want it */ 484 node->flags &= ~NG_BUSY; 485 486 /* If we have sleepers, then wake them up */ 487 if (node->sleepers) 488 wakeup(node); 489 490 /* We also have a reference.. drop it too */ 491 ng_unref(node); 492 } 493 494 /************************************************************************ 495 Node ID handling 496 ************************************************************************/ 497 static node_p 498 ng_ID2node(ng_ID_t ID) 499 { 500 node_p np; 501 LIST_FOREACH(np, &ID_hash[ID % ID_HASH_SIZE], idnodes) { 502 if (np->ID == ID) 503 break; 504 } 505 return(np); 506 } 507 508 ng_ID_t 509 ng_node2ID(node_p node) 510 { 511 return (node->ID); 512 } 513 514 /************************************************************************ 515 Node name handling 516 ************************************************************************/ 517 518 /* 519 * Assign a node a name. Once assigned, the name cannot be changed. 520 */ 521 int 522 ng_name_node(node_p node, const char *name) 523 { 524 int i; 525 526 /* Check the name is valid */ 527 for (i = 0; i < NG_NODELEN + 1; i++) { 528 if (name[i] == '\0' || name[i] == '.' || name[i] == ':') 529 break; 530 } 531 if (i == 0 || name[i] != '\0') { 532 TRAP_ERROR; 533 return (EINVAL); 534 } 535 if (ng_decodeidname(name) != 0) { /* valid IDs not allowed here */ 536 TRAP_ERROR; 537 return (EINVAL); 538 } 539 540 /* Check the node isn't already named */ 541 if (node->name != NULL) { 542 TRAP_ERROR; 543 return (EISCONN); 544 } 545 546 /* Check the name isn't already being used */ 547 if (ng_findname(node, name) != NULL) { 548 TRAP_ERROR; 549 return (EADDRINUSE); 550 } 551 552 /* Allocate space and copy it */ 553 MALLOC(node->name, char *, strlen(name) + 1, M_NETGRAPH, M_WAITOK); 554 if (node->name == NULL) { 555 TRAP_ERROR; 556 return (ENOMEM); 557 } 558 strcpy(node->name, name); 559 560 /* The name counts as a reference */ 561 node->refs++; 562 return (0); 563 } 564 565 /* 566 * Find a node by absolute name. The name should NOT end with ':' 567 * The name "." means "this node" and "[xxx]" means "the node 568 * with ID (ie, at address) xxx". 569 * 570 * Returns the node if found, else NULL. 571 */ 572 node_p 573 ng_findname(node_p this, const char *name) 574 { 575 node_p node; 576 ng_ID_t temp; 577 578 /* "." means "this node" */ 579 if (strcmp(name, ".") == 0) 580 return(this); 581 582 /* Check for name-by-ID */ 583 if ((temp = ng_decodeidname(name)) != 0) { 584 return (ng_ID2node(temp)); 585 } 586 587 /* Find node by name */ 588 LIST_FOREACH(node, &nodelist, nodes) { 589 if (node->name != NULL && strcmp(node->name, name) == 0) 590 break; 591 } 592 return (node); 593 } 594 595 /* 596 * Decode a ID name, eg. "[f03034de]". Returns 0 if the 597 * string is not valid, otherwise returns the value. 598 */ 599 static ng_ID_t 600 ng_decodeidname(const char *name) 601 { 602 const int len = strlen(name); 603 char *eptr; 604 u_long val; 605 606 /* Check for proper length, brackets, no leading junk */ 607 if (len < 3 || name[0] != '[' || name[len - 1] != ']' 608 || !isxdigit(name[1])) 609 return (0); 610 611 /* Decode number */ 612 val = strtoul(name + 1, &eptr, 16); 613 if (eptr - name != len - 1 || val == ULONG_MAX || val == 0) 614 return ((ng_ID_t)0); 615 return (ng_ID_t)val; 616 } 617 618 /* 619 * Remove a name from a node. This should only be called 620 * when shutting down and removing the node. 621 */ 622 void 623 ng_unname(node_p node) 624 { 625 if (node->name) { 626 FREE(node->name, M_NETGRAPH); 627 node->name = NULL; 628 ng_unref(node); 629 } 630 } 631 632 /************************************************************************ 633 Hook routines 634 635 Names are not optional. Hooks are always connected, except for a 636 brief moment within these routines. 637 638 ************************************************************************/ 639 640 /* 641 * Remove a hook reference 642 */ 643 static void 644 ng_unref_hook(hook_p hook) 645 { 646 if (--hook->refs == 0) 647 FREE(hook, M_NETGRAPH); 648 } 649 650 /* 651 * Add an unconnected hook to a node. Only used internally. 652 */ 653 static int 654 ng_add_hook(node_p node, const char *name, hook_p *hookp) 655 { 656 hook_p hook; 657 int error = 0; 658 659 /* Check that the given name is good */ 660 if (name == NULL) { 661 TRAP_ERROR; 662 return (EINVAL); 663 } 664 if (ng_findhook(node, name) != NULL) { 665 TRAP_ERROR; 666 return (EEXIST); 667 } 668 669 /* Allocate the hook and link it up */ 670 MALLOC(hook, hook_p, sizeof(*hook), M_NETGRAPH, M_WAITOK); 671 if (hook == NULL) { 672 TRAP_ERROR; 673 return (ENOMEM); 674 } 675 bzero(hook, sizeof(*hook)); 676 hook->refs = 1; 677 hook->flags = HK_INVALID; 678 hook->node = node; 679 node->refs++; /* each hook counts as a reference */ 680 681 /* Check if the node type code has something to say about it */ 682 if (node->type->newhook != NULL) 683 if ((error = (*node->type->newhook)(node, hook, name)) != 0) 684 goto fail; 685 686 /* 687 * The 'type' agrees so far, so go ahead and link it in. 688 * We'll ask again later when we actually connect the hooks. 689 */ 690 LIST_INSERT_HEAD(&node->hooks, hook, hooks); 691 node->numhooks++; 692 693 /* Set hook name */ 694 MALLOC(hook->name, char *, strlen(name) + 1, M_NETGRAPH, M_WAITOK); 695 if (hook->name == NULL) { 696 error = ENOMEM; 697 LIST_REMOVE(hook, hooks); 698 node->numhooks--; 699 fail: 700 hook->node = NULL; 701 ng_unref(node); 702 ng_unref_hook(hook); /* this frees the hook */ 703 return (error); 704 } 705 strcpy(hook->name, name); 706 if (hookp) 707 *hookp = hook; 708 return (error); 709 } 710 711 /* 712 * Connect a pair of hooks. Only used internally. 713 */ 714 static int 715 ng_connect(hook_p hook1, hook_p hook2) 716 { 717 int error; 718 719 hook1->peer = hook2; 720 hook2->peer = hook1; 721 722 /* Give each node the opportunity to veto the impending connection */ 723 if (hook1->node->type->connect) { 724 if ((error = (*hook1->node->type->connect) (hook1))) { 725 ng_destroy_hook(hook1); /* also zaps hook2 */ 726 return (error); 727 } 728 } 729 if (hook2->node->type->connect) { 730 if ((error = (*hook2->node->type->connect) (hook2))) { 731 ng_destroy_hook(hook2); /* also zaps hook1 */ 732 return (error); 733 } 734 } 735 hook1->flags &= ~HK_INVALID; 736 hook2->flags &= ~HK_INVALID; 737 return (0); 738 } 739 740 /* 741 * Find a hook 742 * 743 * Node types may supply their own optimized routines for finding 744 * hooks. If none is supplied, we just do a linear search. 745 */ 746 hook_p 747 ng_findhook(node_p node, const char *name) 748 { 749 hook_p hook; 750 751 if (node->type->findhook != NULL) 752 return (*node->type->findhook)(node, name); 753 LIST_FOREACH(hook, &node->hooks, hooks) { 754 if (hook->name != NULL && strcmp(hook->name, name) == 0) 755 return (hook); 756 } 757 return (NULL); 758 } 759 760 /* 761 * Destroy a hook 762 * 763 * As hooks are always attached, this really destroys two hooks. 764 * The one given, and the one attached to it. Disconnect the hooks 765 * from each other first. 766 */ 767 void 768 ng_destroy_hook(hook_p hook) 769 { 770 hook_p peer = hook->peer; 771 772 hook->flags |= HK_INVALID; /* as soon as possible */ 773 if (peer) { 774 peer->flags |= HK_INVALID; /* as soon as possible */ 775 hook->peer = NULL; 776 peer->peer = NULL; 777 ng_disconnect_hook(peer); 778 } 779 ng_disconnect_hook(hook); 780 } 781 782 /* 783 * Notify the node of the hook's demise. This may result in more actions 784 * (e.g. shutdown) but we don't do that ourselves and don't know what 785 * happens there. If there is no appropriate handler, then just remove it 786 * (and decrement the reference count of it's node which in turn might 787 * make something happen). 788 */ 789 static void 790 ng_disconnect_hook(hook_p hook) 791 { 792 node_p node = hook->node; 793 794 /* 795 * Remove the hook from the node's list to avoid possible recursion 796 * in case the disconnection results in node shutdown. 797 */ 798 LIST_REMOVE(hook, hooks); 799 node->numhooks--; 800 if (node->type->disconnect) { 801 /* 802 * The type handler may elect to destroy the peer so don't 803 * trust its existance after this point. 804 */ 805 (*node->type->disconnect) (hook); 806 } 807 ng_unref(node); /* might be the last reference */ 808 if (hook->name) 809 FREE(hook->name, M_NETGRAPH); 810 hook->node = NULL; /* may still be referenced elsewhere */ 811 ng_unref_hook(hook); 812 } 813 814 /* 815 * Take two hooks on a node and merge the connection so that the given node 816 * is effectively bypassed. 817 */ 818 int 819 ng_bypass(hook_p hook1, hook_p hook2) 820 { 821 if (hook1->node != hook2->node) 822 return (EINVAL); 823 hook1->peer->peer = hook2->peer; 824 hook2->peer->peer = hook1->peer; 825 826 /* XXX If we ever cache methods on hooks update them as well */ 827 hook1->peer = NULL; 828 hook2->peer = NULL; 829 ng_destroy_hook(hook1); 830 ng_destroy_hook(hook2); 831 return (0); 832 } 833 834 /* 835 * Install a new netgraph type 836 */ 837 int 838 ng_newtype(struct ng_type *tp) 839 { 840 const size_t namelen = strlen(tp->name); 841 842 /* Check version and type name fields */ 843 if (tp->version != NG_VERSION || namelen == 0 || namelen > NG_TYPELEN) { 844 TRAP_ERROR; 845 return (EINVAL); 846 } 847 848 /* Check for name collision */ 849 if (ng_findtype(tp->name) != NULL) { 850 TRAP_ERROR; 851 return (EEXIST); 852 } 853 854 /* Link in new type */ 855 LIST_INSERT_HEAD(&typelist, tp, types); 856 tp->refs = 0; 857 return (0); 858 } 859 860 /* 861 * Look for a type of the name given 862 */ 863 struct ng_type * 864 ng_findtype(const char *typename) 865 { 866 struct ng_type *type; 867 868 LIST_FOREACH(type, &typelist, types) { 869 if (strcmp(type->name, typename) == 0) 870 break; 871 } 872 return (type); 873 } 874 875 876 /************************************************************************ 877 Composite routines 878 ************************************************************************/ 879 880 /* 881 * Make a peer and connect. The order is arranged to minimise 882 * the work needed to back out in case of error. 883 */ 884 int 885 ng_mkpeer(node_p node, const char *name, const char *name2, char *type) 886 { 887 node_p node2; 888 hook_p hook; 889 hook_p hook2; 890 int error; 891 892 if ((error = ng_add_hook(node, name, &hook))) 893 return (error); 894 if ((error = ng_make_node(type, &node2))) { 895 ng_destroy_hook(hook); 896 return (error); 897 } 898 if ((error = ng_add_hook(node2, name2, &hook2))) { 899 ng_rmnode(node2); 900 ng_destroy_hook(hook); 901 return (error); 902 } 903 904 /* 905 * Actually link the two hooks together.. on failure they are 906 * destroyed so we don't have to do that here. 907 */ 908 if ((error = ng_connect(hook, hook2))) 909 ng_rmnode(node2); 910 return (error); 911 } 912 913 /* 914 * Connect two nodes using the specified hooks 915 */ 916 int 917 ng_con_nodes(node_p node, const char *name, node_p node2, const char *name2) 918 { 919 int error; 920 hook_p hook; 921 hook_p hook2; 922 923 if ((error = ng_add_hook(node, name, &hook))) 924 return (error); 925 if ((error = ng_add_hook(node2, name2, &hook2))) { 926 ng_destroy_hook(hook); 927 return (error); 928 } 929 return (ng_connect(hook, hook2)); 930 } 931 932 /* 933 * Parse and verify a string of the form: <NODE:><PATH> 934 * 935 * Such a string can refer to a specific node or a specific hook 936 * on a specific node, depending on how you look at it. In the 937 * latter case, the PATH component must not end in a dot. 938 * 939 * Both <NODE:> and <PATH> are optional. The <PATH> is a string 940 * of hook names separated by dots. This breaks out the original 941 * string, setting *nodep to "NODE" (or NULL if none) and *pathp 942 * to "PATH" (or NULL if degenerate). Also, *hookp will point to 943 * the final hook component of <PATH>, if any, otherwise NULL. 944 * 945 * This returns -1 if the path is malformed. The char ** are optional. 946 */ 947 948 int 949 ng_path_parse(char *addr, char **nodep, char **pathp, char **hookp) 950 { 951 char *node, *path, *hook; 952 int k; 953 954 /* 955 * Extract absolute NODE, if any 956 */ 957 for (path = addr; *path && *path != ':'; path++); 958 if (*path) { 959 node = addr; /* Here's the NODE */ 960 *path++ = '\0'; /* Here's the PATH */ 961 962 /* Node name must not be empty */ 963 if (!*node) 964 return -1; 965 966 /* A name of "." is OK; otherwise '.' not allowed */ 967 if (strcmp(node, ".") != 0) { 968 for (k = 0; node[k]; k++) 969 if (node[k] == '.') 970 return -1; 971 } 972 } else { 973 node = NULL; /* No absolute NODE */ 974 path = addr; /* Here's the PATH */ 975 } 976 977 /* Snoop for illegal characters in PATH */ 978 for (k = 0; path[k]; k++) 979 if (path[k] == ':') 980 return -1; 981 982 /* Check for no repeated dots in PATH */ 983 for (k = 0; path[k]; k++) 984 if (path[k] == '.' && path[k + 1] == '.') 985 return -1; 986 987 /* Remove extra (degenerate) dots from beginning or end of PATH */ 988 if (path[0] == '.') 989 path++; 990 if (*path && path[strlen(path) - 1] == '.') 991 path[strlen(path) - 1] = 0; 992 993 /* If PATH has a dot, then we're not talking about a hook */ 994 if (*path) { 995 for (hook = path, k = 0; path[k]; k++) 996 if (path[k] == '.') { 997 hook = NULL; 998 break; 999 } 1000 } else 1001 path = hook = NULL; 1002 1003 /* Done */ 1004 if (nodep) 1005 *nodep = node; 1006 if (pathp) 1007 *pathp = path; 1008 if (hookp) 1009 *hookp = hook; 1010 return (0); 1011 } 1012 1013 /* 1014 * Given a path, which may be absolute or relative, and a starting node, 1015 * return the destination node. Compute the "return address" if desired. 1016 */ 1017 int 1018 ng_path2node(node_p here, const char *address, node_p *destp, char **rtnp) 1019 { 1020 const node_p start = here; 1021 char fullpath[NG_PATHLEN + 1]; 1022 char *nodename, *path, pbuf[2]; 1023 node_p node; 1024 char *cp; 1025 1026 /* Initialize */ 1027 if (rtnp) 1028 *rtnp = NULL; 1029 if (destp == NULL) 1030 return EINVAL; 1031 *destp = NULL; 1032 1033 /* Make a writable copy of address for ng_path_parse() */ 1034 strncpy(fullpath, address, sizeof(fullpath) - 1); 1035 fullpath[sizeof(fullpath) - 1] = '\0'; 1036 1037 /* Parse out node and sequence of hooks */ 1038 if (ng_path_parse(fullpath, &nodename, &path, NULL) < 0) { 1039 TRAP_ERROR; 1040 return EINVAL; 1041 } 1042 if (path == NULL) { 1043 pbuf[0] = '.'; /* Needs to be writable */ 1044 pbuf[1] = '\0'; 1045 path = pbuf; 1046 } 1047 1048 /* For an absolute address, jump to the starting node */ 1049 if (nodename) { 1050 node = ng_findname(here, nodename); 1051 if (node == NULL) { 1052 TRAP_ERROR; 1053 return (ENOENT); 1054 } 1055 } else 1056 node = here; 1057 1058 /* Now follow the sequence of hooks */ 1059 for (cp = path; node != NULL && *cp != '\0'; ) { 1060 hook_p hook; 1061 char *segment; 1062 1063 /* 1064 * Break out the next path segment. Replace the dot we just 1065 * found with a NUL; "cp" points to the next segment (or the 1066 * NUL at the end). 1067 */ 1068 for (segment = cp; *cp != '\0'; cp++) { 1069 if (*cp == '.') { 1070 *cp++ = '\0'; 1071 break; 1072 } 1073 } 1074 1075 /* Empty segment */ 1076 if (*segment == '\0') 1077 continue; 1078 1079 /* We have a segment, so look for a hook by that name */ 1080 hook = ng_findhook(node, segment); 1081 1082 /* Can't get there from here... */ 1083 if (hook == NULL 1084 || hook->peer == NULL 1085 || (hook->flags & HK_INVALID) != 0) { 1086 TRAP_ERROR; 1087 return (ENOENT); 1088 } 1089 1090 /* Hop on over to the next node */ 1091 node = hook->peer->node; 1092 } 1093 1094 /* If node somehow missing, fail here (probably this is not needed) */ 1095 if (node == NULL) { 1096 TRAP_ERROR; 1097 return (ENXIO); 1098 } 1099 1100 /* Now compute return address, i.e., the path to the sender */ 1101 if (rtnp != NULL) { 1102 MALLOC(*rtnp, char *, NG_NODELEN + 2, M_NETGRAPH, M_WAITOK); 1103 if (*rtnp == NULL) { 1104 TRAP_ERROR; 1105 return (ENOMEM); 1106 } 1107 if (start->name != NULL) 1108 sprintf(*rtnp, "%s:", start->name); 1109 else 1110 sprintf(*rtnp, "[%x]:", ng_node2ID(start)); 1111 } 1112 1113 /* Done */ 1114 *destp = node; 1115 return (0); 1116 } 1117 1118 /* 1119 * Call the appropriate message handler for the object. 1120 * It is up to the message handler to free the message. 1121 * If it's a generic message, handle it generically, otherwise 1122 * call the type's message handler (if it exists) 1123 */ 1124 1125 #define CALL_MSG_HANDLER(error, node, msg, retaddr, resp) \ 1126 do { \ 1127 if((msg)->header.typecookie == NGM_GENERIC_COOKIE) { \ 1128 (error) = ng_generic_msg((node), (msg), \ 1129 (retaddr), (resp)); \ 1130 } else { \ 1131 if ((node)->type->rcvmsg != NULL) { \ 1132 (error) = (*(node)->type->rcvmsg)((node), \ 1133 (msg), (retaddr), (resp)); \ 1134 } else { \ 1135 TRAP_ERROR; \ 1136 FREE((msg), M_NETGRAPH); \ 1137 (error) = EINVAL; \ 1138 } \ 1139 } \ 1140 } while (0) 1141 1142 1143 /* 1144 * Send a control message to a node 1145 */ 1146 int 1147 ng_send_msg(node_p here, struct ng_mesg *msg, const char *address, 1148 struct ng_mesg **rptr) 1149 { 1150 node_p dest = NULL; 1151 char *retaddr = NULL; 1152 int error; 1153 1154 /* Find the target node */ 1155 error = ng_path2node(here, address, &dest, &retaddr); 1156 if (error) { 1157 FREE(msg, M_NETGRAPH); 1158 return error; 1159 } 1160 1161 /* Make sure the resp field is null before we start */ 1162 if (rptr != NULL) 1163 *rptr = NULL; 1164 1165 CALL_MSG_HANDLER(error, dest, msg, retaddr, rptr); 1166 1167 /* Make sure that if there is a response, it has the RESP bit set */ 1168 if ((error == 0) && rptr && *rptr) 1169 (*rptr)->header.flags |= NGF_RESP; 1170 1171 /* 1172 * If we had a return address it is up to us to free it. They should 1173 * have taken a copy if they needed to make a delayed response. 1174 */ 1175 if (retaddr) 1176 FREE(retaddr, M_NETGRAPH); 1177 return (error); 1178 } 1179 1180 /* 1181 * Implement the 'generic' control messages 1182 */ 1183 static int 1184 ng_generic_msg(node_p here, struct ng_mesg *msg, const char *retaddr, 1185 struct ng_mesg **resp) 1186 { 1187 int error = 0; 1188 1189 if (msg->header.typecookie != NGM_GENERIC_COOKIE) { 1190 TRAP_ERROR; 1191 FREE(msg, M_NETGRAPH); 1192 return (EINVAL); 1193 } 1194 switch (msg->header.cmd) { 1195 case NGM_SHUTDOWN: 1196 ng_rmnode(here); 1197 break; 1198 case NGM_MKPEER: 1199 { 1200 struct ngm_mkpeer *const mkp = (struct ngm_mkpeer *) msg->data; 1201 1202 if (msg->header.arglen != sizeof(*mkp)) { 1203 TRAP_ERROR; 1204 return (EINVAL); 1205 } 1206 mkp->type[sizeof(mkp->type) - 1] = '\0'; 1207 mkp->ourhook[sizeof(mkp->ourhook) - 1] = '\0'; 1208 mkp->peerhook[sizeof(mkp->peerhook) - 1] = '\0'; 1209 error = ng_mkpeer(here, mkp->ourhook, mkp->peerhook, mkp->type); 1210 break; 1211 } 1212 case NGM_CONNECT: 1213 { 1214 struct ngm_connect *const con = 1215 (struct ngm_connect *) msg->data; 1216 node_p node2; 1217 1218 if (msg->header.arglen != sizeof(*con)) { 1219 TRAP_ERROR; 1220 return (EINVAL); 1221 } 1222 con->path[sizeof(con->path) - 1] = '\0'; 1223 con->ourhook[sizeof(con->ourhook) - 1] = '\0'; 1224 con->peerhook[sizeof(con->peerhook) - 1] = '\0'; 1225 error = ng_path2node(here, con->path, &node2, NULL); 1226 if (error) 1227 break; 1228 error = ng_con_nodes(here, con->ourhook, node2, con->peerhook); 1229 break; 1230 } 1231 case NGM_NAME: 1232 { 1233 struct ngm_name *const nam = (struct ngm_name *) msg->data; 1234 1235 if (msg->header.arglen != sizeof(*nam)) { 1236 TRAP_ERROR; 1237 return (EINVAL); 1238 } 1239 nam->name[sizeof(nam->name) - 1] = '\0'; 1240 error = ng_name_node(here, nam->name); 1241 break; 1242 } 1243 case NGM_RMHOOK: 1244 { 1245 struct ngm_rmhook *const rmh = (struct ngm_rmhook *) msg->data; 1246 hook_p hook; 1247 1248 if (msg->header.arglen != sizeof(*rmh)) { 1249 TRAP_ERROR; 1250 return (EINVAL); 1251 } 1252 rmh->ourhook[sizeof(rmh->ourhook) - 1] = '\0'; 1253 if ((hook = ng_findhook(here, rmh->ourhook)) != NULL) 1254 ng_destroy_hook(hook); 1255 break; 1256 } 1257 case NGM_NODEINFO: 1258 { 1259 struct nodeinfo *ni; 1260 struct ng_mesg *rp; 1261 1262 /* Get response struct */ 1263 if (resp == NULL) { 1264 error = EINVAL; 1265 break; 1266 } 1267 NG_MKRESPONSE(rp, msg, sizeof(*ni), M_NOWAIT); 1268 if (rp == NULL) { 1269 error = ENOMEM; 1270 break; 1271 } 1272 1273 /* Fill in node info */ 1274 ni = (struct nodeinfo *) rp->data; 1275 if (here->name != NULL) 1276 strncpy(ni->name, here->name, NG_NODELEN); 1277 strncpy(ni->type, here->type->name, NG_TYPELEN); 1278 ni->id = ng_node2ID(here); 1279 ni->hooks = here->numhooks; 1280 *resp = rp; 1281 break; 1282 } 1283 case NGM_LISTHOOKS: 1284 { 1285 const int nhooks = here->numhooks; 1286 struct hooklist *hl; 1287 struct nodeinfo *ni; 1288 struct ng_mesg *rp; 1289 hook_p hook; 1290 1291 /* Get response struct */ 1292 if (resp == NULL) { 1293 error = EINVAL; 1294 break; 1295 } 1296 NG_MKRESPONSE(rp, msg, sizeof(*hl) 1297 + (nhooks * sizeof(struct linkinfo)), M_NOWAIT); 1298 if (rp == NULL) { 1299 error = ENOMEM; 1300 break; 1301 } 1302 hl = (struct hooklist *) rp->data; 1303 ni = &hl->nodeinfo; 1304 1305 /* Fill in node info */ 1306 if (here->name) 1307 strncpy(ni->name, here->name, NG_NODELEN); 1308 strncpy(ni->type, here->type->name, NG_TYPELEN); 1309 ni->id = ng_node2ID(here); 1310 1311 /* Cycle through the linked list of hooks */ 1312 ni->hooks = 0; 1313 LIST_FOREACH(hook, &here->hooks, hooks) { 1314 struct linkinfo *const link = &hl->link[ni->hooks]; 1315 1316 if (ni->hooks >= nhooks) { 1317 log(LOG_ERR, "%s: number of %s changed\n", 1318 __FUNCTION__, "hooks"); 1319 break; 1320 } 1321 if ((hook->flags & HK_INVALID) != 0) 1322 continue; 1323 strncpy(link->ourhook, hook->name, NG_HOOKLEN); 1324 strncpy(link->peerhook, hook->peer->name, NG_HOOKLEN); 1325 if (hook->peer->node->name != NULL) 1326 strncpy(link->nodeinfo.name, 1327 hook->peer->node->name, NG_NODELEN); 1328 strncpy(link->nodeinfo.type, 1329 hook->peer->node->type->name, NG_TYPELEN); 1330 link->nodeinfo.id = ng_node2ID(hook->peer->node); 1331 link->nodeinfo.hooks = hook->peer->node->numhooks; 1332 ni->hooks++; 1333 } 1334 *resp = rp; 1335 break; 1336 } 1337 1338 case NGM_LISTNAMES: 1339 case NGM_LISTNODES: 1340 { 1341 const int unnamed = (msg->header.cmd == NGM_LISTNODES); 1342 struct namelist *nl; 1343 struct ng_mesg *rp; 1344 node_p node; 1345 int num = 0; 1346 1347 if (resp == NULL) { 1348 error = EINVAL; 1349 break; 1350 } 1351 1352 /* Count number of nodes */ 1353 LIST_FOREACH(node, &nodelist, nodes) { 1354 if (unnamed || node->name != NULL) 1355 num++; 1356 } 1357 1358 /* Get response struct */ 1359 if (resp == NULL) { 1360 error = EINVAL; 1361 break; 1362 } 1363 NG_MKRESPONSE(rp, msg, sizeof(*nl) 1364 + (num * sizeof(struct nodeinfo)), M_NOWAIT); 1365 if (rp == NULL) { 1366 error = ENOMEM; 1367 break; 1368 } 1369 nl = (struct namelist *) rp->data; 1370 1371 /* Cycle through the linked list of nodes */ 1372 nl->numnames = 0; 1373 LIST_FOREACH(node, &nodelist, nodes) { 1374 struct nodeinfo *const np = &nl->nodeinfo[nl->numnames]; 1375 1376 if (nl->numnames >= num) { 1377 log(LOG_ERR, "%s: number of %s changed\n", 1378 __FUNCTION__, "nodes"); 1379 break; 1380 } 1381 if ((node->flags & NG_INVALID) != 0) 1382 continue; 1383 if (!unnamed && node->name == NULL) 1384 continue; 1385 if (node->name != NULL) 1386 strncpy(np->name, node->name, NG_NODELEN); 1387 strncpy(np->type, node->type->name, NG_TYPELEN); 1388 np->id = ng_node2ID(node); 1389 np->hooks = node->numhooks; 1390 nl->numnames++; 1391 } 1392 *resp = rp; 1393 break; 1394 } 1395 1396 case NGM_LISTTYPES: 1397 { 1398 struct typelist *tl; 1399 struct ng_mesg *rp; 1400 struct ng_type *type; 1401 int num = 0; 1402 1403 if (resp == NULL) { 1404 error = EINVAL; 1405 break; 1406 } 1407 1408 /* Count number of types */ 1409 LIST_FOREACH(type, &typelist, types) 1410 num++; 1411 1412 /* Get response struct */ 1413 if (resp == NULL) { 1414 error = EINVAL; 1415 break; 1416 } 1417 NG_MKRESPONSE(rp, msg, sizeof(*tl) 1418 + (num * sizeof(struct typeinfo)), M_NOWAIT); 1419 if (rp == NULL) { 1420 error = ENOMEM; 1421 break; 1422 } 1423 tl = (struct typelist *) rp->data; 1424 1425 /* Cycle through the linked list of types */ 1426 tl->numtypes = 0; 1427 LIST_FOREACH(type, &typelist, types) { 1428 struct typeinfo *const tp = &tl->typeinfo[tl->numtypes]; 1429 1430 if (tl->numtypes >= num) { 1431 log(LOG_ERR, "%s: number of %s changed\n", 1432 __FUNCTION__, "types"); 1433 break; 1434 } 1435 strncpy(tp->typename, type->name, NG_TYPELEN); 1436 tp->numnodes = type->refs; 1437 tl->numtypes++; 1438 } 1439 *resp = rp; 1440 break; 1441 } 1442 1443 case NGM_BINARY2ASCII: 1444 { 1445 int bufSize = 2000; /* XXX hard coded constant */ 1446 const struct ng_parse_type *argstype; 1447 const struct ng_cmdlist *c; 1448 struct ng_mesg *rp, *binary, *ascii; 1449 1450 /* Data area must contain a valid netgraph message */ 1451 binary = (struct ng_mesg *)msg->data; 1452 if (msg->header.arglen < sizeof(struct ng_mesg) 1453 || msg->header.arglen - sizeof(struct ng_mesg) 1454 < binary->header.arglen) { 1455 error = EINVAL; 1456 break; 1457 } 1458 1459 /* Get a response message with lots of room */ 1460 NG_MKRESPONSE(rp, msg, sizeof(*ascii) + bufSize, M_NOWAIT); 1461 if (rp == NULL) { 1462 error = ENOMEM; 1463 break; 1464 } 1465 ascii = (struct ng_mesg *)rp->data; 1466 1467 /* Copy binary message header to response message payload */ 1468 bcopy(binary, ascii, sizeof(*binary)); 1469 1470 /* Find command by matching typecookie and command number */ 1471 for (c = here->type->cmdlist; 1472 c != NULL && c->name != NULL; c++) { 1473 if (binary->header.typecookie == c->cookie 1474 && binary->header.cmd == c->cmd) 1475 break; 1476 } 1477 if (c == NULL || c->name == NULL) { 1478 for (c = ng_generic_cmds; c->name != NULL; c++) { 1479 if (binary->header.typecookie == c->cookie 1480 && binary->header.cmd == c->cmd) 1481 break; 1482 } 1483 if (c->name == NULL) { 1484 FREE(rp, M_NETGRAPH); 1485 error = ENOSYS; 1486 break; 1487 } 1488 } 1489 1490 /* Convert command name to ASCII */ 1491 snprintf(ascii->header.cmdstr, sizeof(ascii->header.cmdstr), 1492 "%s", c->name); 1493 1494 /* Convert command arguments to ASCII */ 1495 argstype = (binary->header.flags & NGF_RESP) ? 1496 c->respType : c->mesgType; 1497 if (argstype == NULL) 1498 *ascii->data = '\0'; 1499 else { 1500 if ((error = ng_unparse(argstype, 1501 (u_char *)binary->data, 1502 ascii->data, bufSize)) != 0) { 1503 FREE(rp, M_NETGRAPH); 1504 break; 1505 } 1506 } 1507 1508 /* Return the result as struct ng_mesg plus ASCII string */ 1509 bufSize = strlen(ascii->data) + 1; 1510 ascii->header.arglen = bufSize; 1511 rp->header.arglen = sizeof(*ascii) + bufSize; 1512 *resp = rp; 1513 break; 1514 } 1515 1516 case NGM_ASCII2BINARY: 1517 { 1518 int bufSize = 2000; /* XXX hard coded constant */ 1519 const struct ng_cmdlist *c; 1520 const struct ng_parse_type *argstype; 1521 struct ng_mesg *rp, *ascii, *binary; 1522 int off; 1523 1524 /* Data area must contain at least a struct ng_mesg + '\0' */ 1525 ascii = (struct ng_mesg *)msg->data; 1526 if (msg->header.arglen < sizeof(*ascii) + 1 1527 || ascii->header.arglen < 1 1528 || msg->header.arglen 1529 < sizeof(*ascii) + ascii->header.arglen) { 1530 error = EINVAL; 1531 break; 1532 } 1533 ascii->data[ascii->header.arglen - 1] = '\0'; 1534 1535 /* Get a response message with lots of room */ 1536 NG_MKRESPONSE(rp, msg, sizeof(*binary) + bufSize, M_NOWAIT); 1537 if (rp == NULL) { 1538 error = ENOMEM; 1539 break; 1540 } 1541 binary = (struct ng_mesg *)rp->data; 1542 1543 /* Copy ASCII message header to response message payload */ 1544 bcopy(ascii, binary, sizeof(*ascii)); 1545 1546 /* Find command by matching ASCII command string */ 1547 for (c = here->type->cmdlist; 1548 c != NULL && c->name != NULL; c++) { 1549 if (strcmp(ascii->header.cmdstr, c->name) == 0) 1550 break; 1551 } 1552 if (c == NULL || c->name == NULL) { 1553 for (c = ng_generic_cmds; c->name != NULL; c++) { 1554 if (strcmp(ascii->header.cmdstr, c->name) == 0) 1555 break; 1556 } 1557 if (c->name == NULL) { 1558 FREE(rp, M_NETGRAPH); 1559 error = ENOSYS; 1560 break; 1561 } 1562 } 1563 1564 /* Convert command name to binary */ 1565 binary->header.cmd = c->cmd; 1566 binary->header.typecookie = c->cookie; 1567 1568 /* Convert command arguments to binary */ 1569 argstype = (binary->header.flags & NGF_RESP) ? 1570 c->respType : c->mesgType; 1571 if (argstype == NULL) 1572 bufSize = 0; 1573 else { 1574 if ((error = ng_parse(argstype, ascii->data, 1575 &off, (u_char *)binary->data, &bufSize)) != 0) { 1576 FREE(rp, M_NETGRAPH); 1577 break; 1578 } 1579 } 1580 1581 /* Return the result */ 1582 binary->header.arglen = bufSize; 1583 rp->header.arglen = sizeof(*binary) + bufSize; 1584 *resp = rp; 1585 break; 1586 } 1587 1588 case NGM_TEXT_STATUS: 1589 /* 1590 * This one is tricky as it passes the command down to the 1591 * actual node, even though it is a generic type command. 1592 * This means we must assume that the msg is already freed 1593 * when control passes back to us. 1594 */ 1595 if (resp == NULL) { 1596 error = EINVAL; 1597 break; 1598 } 1599 if (here->type->rcvmsg != NULL) 1600 return((*here->type->rcvmsg)(here, msg, retaddr, resp)); 1601 /* Fall through if rcvmsg not supported */ 1602 default: 1603 TRAP_ERROR; 1604 error = EINVAL; 1605 } 1606 FREE(msg, M_NETGRAPH); 1607 return (error); 1608 } 1609 1610 /* 1611 * Send a data packet to a node. If the recipient has no 1612 * 'receive data' method, then silently discard the packet. 1613 */ 1614 int 1615 ng_send_data(hook_p hook, struct mbuf *m, meta_p meta) 1616 { 1617 int (*rcvdata)(hook_p, struct mbuf *, meta_p); 1618 int error; 1619 1620 CHECK_DATA_MBUF(m); 1621 if (hook && (hook->flags & HK_INVALID) == 0) { 1622 rcvdata = hook->peer->node->type->rcvdata; 1623 if (rcvdata != NULL) 1624 error = (*rcvdata)(hook->peer, m, meta); 1625 else { 1626 error = 0; 1627 NG_FREE_DATA(m, meta); 1628 } 1629 } else { 1630 TRAP_ERROR; 1631 error = ENOTCONN; 1632 NG_FREE_DATA(m, meta); 1633 } 1634 return (error); 1635 } 1636 1637 /* 1638 * Send a queued data packet to a node. If the recipient has no 1639 * 'receive queued data' method, then try the 'receive data' method above. 1640 */ 1641 int 1642 ng_send_dataq(hook_p hook, struct mbuf *m, meta_p meta) 1643 { 1644 int (*rcvdataq)(hook_p, struct mbuf *, meta_p); 1645 int error; 1646 1647 CHECK_DATA_MBUF(m); 1648 if (hook && (hook->flags & HK_INVALID) == 0) { 1649 rcvdataq = hook->peer->node->type->rcvdataq; 1650 if (rcvdataq != NULL) 1651 error = (*rcvdataq)(hook->peer, m, meta); 1652 else { 1653 error = ng_send_data(hook, m, meta); 1654 } 1655 } else { 1656 TRAP_ERROR; 1657 error = ENOTCONN; 1658 NG_FREE_DATA(m, meta); 1659 } 1660 return (error); 1661 } 1662 1663 /************************************************************************ 1664 Module routines 1665 ************************************************************************/ 1666 1667 /* 1668 * Handle the loading/unloading of a netgraph node type module 1669 */ 1670 int 1671 ng_mod_event(module_t mod, int event, void *data) 1672 { 1673 struct ng_type *const type = data; 1674 int s, error = 0; 1675 1676 switch (event) { 1677 case MOD_LOAD: 1678 1679 /* Register new netgraph node type */ 1680 s = splnet(); 1681 if ((error = ng_newtype(type)) != 0) { 1682 splx(s); 1683 break; 1684 } 1685 1686 /* Call type specific code */ 1687 if (type->mod_event != NULL) 1688 if ((error = (*type->mod_event)(mod, event, data)) != 0) 1689 LIST_REMOVE(type, types); 1690 splx(s); 1691 break; 1692 1693 case MOD_UNLOAD: 1694 s = splnet(); 1695 if (type->refs != 0) /* make sure no nodes exist! */ 1696 error = EBUSY; 1697 else { 1698 if (type->mod_event != NULL) { /* check with type */ 1699 error = (*type->mod_event)(mod, event, data); 1700 if (error != 0) { /* type refuses.. */ 1701 splx(s); 1702 break; 1703 } 1704 } 1705 LIST_REMOVE(type, types); 1706 } 1707 splx(s); 1708 break; 1709 1710 default: 1711 if (type->mod_event != NULL) 1712 error = (*type->mod_event)(mod, event, data); 1713 else 1714 error = 0; /* XXX ? */ 1715 break; 1716 } 1717 return (error); 1718 } 1719 1720 /* 1721 * Handle loading and unloading for this code. 1722 * The only thing we need to link into is the NETISR strucure. 1723 */ 1724 static int 1725 ngb_mod_event(module_t mod, int event, void *data) 1726 { 1727 int s, error = 0; 1728 1729 switch (event) { 1730 case MOD_LOAD: 1731 /* Register line discipline */ 1732 s = splimp(); 1733 error = register_netisr(NETISR_NETGRAPH, ngintr); 1734 splx(s); 1735 break; 1736 case MOD_UNLOAD: 1737 /* You cant unload it because an interface may be using it. */ 1738 error = EBUSY; 1739 break; 1740 default: 1741 error = EOPNOTSUPP; 1742 break; 1743 } 1744 return (error); 1745 } 1746 1747 static moduledata_t netgraph_mod = { 1748 "netgraph", 1749 ngb_mod_event, 1750 (NULL) 1751 }; 1752 DECLARE_MODULE(netgraph, netgraph_mod, SI_SUB_DRIVERS, SI_ORDER_MIDDLE); 1753 1754 /************************************************************************ 1755 Queueing routines 1756 ************************************************************************/ 1757 1758 /* The structure for queueing across ISR switches */ 1759 struct ng_queue_entry { 1760 u_long flags; 1761 struct ng_queue_entry *next; 1762 union { 1763 struct { 1764 hook_p da_hook; /* target hook */ 1765 struct mbuf *da_m; 1766 meta_p da_meta; 1767 } data; 1768 struct { 1769 struct ng_mesg *msg_msg; 1770 node_p msg_node; 1771 void *msg_retaddr; 1772 } msg; 1773 } body; 1774 }; 1775 #define NGQF_DATA 0x01 /* the queue element is data */ 1776 #define NGQF_MESG 0x02 /* the queue element is a message */ 1777 1778 static struct ng_queue_entry *ngqbase; /* items to be unqueued */ 1779 static struct ng_queue_entry *ngqlast; /* last item queued */ 1780 static const int ngqroom = 64; /* max items to queue */ 1781 static int ngqsize; /* number of items in queue */ 1782 1783 static struct ng_queue_entry *ngqfree; /* free ones */ 1784 static const int ngqfreemax = 16;/* cache at most this many */ 1785 static int ngqfreesize; /* number of cached entries */ 1786 1787 /* 1788 * Get a queue entry 1789 */ 1790 static struct ng_queue_entry * 1791 ng_getqblk(void) 1792 { 1793 register struct ng_queue_entry *q; 1794 int s; 1795 1796 /* Could be guarding against tty ints or whatever */ 1797 s = splhigh(); 1798 1799 /* Try get a cached queue block, or else allocate a new one */ 1800 if ((q = ngqfree) == NULL) { 1801 splx(s); 1802 if (ngqsize < ngqroom) { /* don't worry about races */ 1803 MALLOC(q, struct ng_queue_entry *, 1804 sizeof(*q), M_NETGRAPH, M_NOWAIT); 1805 } 1806 } else { 1807 ngqfree = q->next; 1808 ngqfreesize--; 1809 splx(s); 1810 } 1811 return (q); 1812 } 1813 1814 /* 1815 * Release a queue entry 1816 */ 1817 #define RETURN_QBLK(q) \ 1818 do { \ 1819 int s; \ 1820 if (ngqfreesize < ngqfreemax) { /* don't worry about races */ \ 1821 s = splhigh(); \ 1822 (q)->next = ngqfree; \ 1823 ngqfree = (q); \ 1824 ngqfreesize++; \ 1825 splx(s); \ 1826 } else { \ 1827 FREE((q), M_NETGRAPH); \ 1828 } \ 1829 } while (0) 1830 1831 /* 1832 * Running at a raised (but we don't know which) processor priority level, 1833 * put the data onto a queue to be picked up by another PPL (probably splnet) 1834 */ 1835 int 1836 ng_queue_data(hook_p hook, struct mbuf *m, meta_p meta) 1837 { 1838 struct ng_queue_entry *q; 1839 int s; 1840 1841 if (hook == NULL) { 1842 NG_FREE_DATA(m, meta); 1843 return (0); 1844 } 1845 if ((q = ng_getqblk()) == NULL) { 1846 NG_FREE_DATA(m, meta); 1847 return (ENOBUFS); 1848 } 1849 1850 /* Fill out the contents */ 1851 q->flags = NGQF_DATA; 1852 q->next = NULL; 1853 q->body.data.da_hook = hook; 1854 q->body.data.da_m = m; 1855 q->body.data.da_meta = meta; 1856 hook->refs++; /* don't let it go away while on the queue */ 1857 1858 /* Put it on the queue */ 1859 s = splhigh(); 1860 if (ngqbase) { 1861 ngqlast->next = q; 1862 } else { 1863 ngqbase = q; 1864 } 1865 ngqlast = q; 1866 ngqsize++; 1867 splx(s); 1868 1869 /* Schedule software interrupt to handle it later */ 1870 schednetisr(NETISR_NETGRAPH); 1871 return (0); 1872 } 1873 1874 /* 1875 * Running at a raised (but we don't know which) processor priority level, 1876 * put the msg onto a queue to be picked up by another PPL (probably splnet) 1877 */ 1878 int 1879 ng_queue_msg(node_p here, struct ng_mesg * msg, int len, const char *address) 1880 { 1881 register struct ng_queue_entry *q; 1882 int s; 1883 node_p dest = NULL; 1884 char *retaddr = NULL; 1885 int error; 1886 1887 /* Find the target node. */ 1888 error = ng_path2node(here, address, &dest, &retaddr); 1889 if (error) { 1890 FREE(msg, M_NETGRAPH); 1891 return (error); 1892 } 1893 if ((q = ng_getqblk()) == NULL) { 1894 FREE(msg, M_NETGRAPH); 1895 if (retaddr) 1896 FREE(retaddr, M_NETGRAPH); 1897 return (ENOBUFS); 1898 } 1899 1900 /* Fill out the contents */ 1901 q->flags = NGQF_MESG; 1902 q->next = NULL; 1903 q->body.msg.msg_node = dest; 1904 q->body.msg.msg_msg = msg; 1905 q->body.msg.msg_retaddr = retaddr; 1906 dest->refs++; /* don't let it go away while on the queue */ 1907 1908 /* Put it on the queue */ 1909 s = splhigh(); 1910 if (ngqbase) { 1911 ngqlast->next = q; 1912 } else { 1913 ngqbase = q; 1914 } 1915 ngqlast = q; 1916 ngqsize++; 1917 splx(s); 1918 1919 /* Schedule software interrupt to handle it later */ 1920 schednetisr(NETISR_NETGRAPH); 1921 return (0); 1922 } 1923 1924 /* 1925 * Pick an item off the queue, process it, and dispose of the queue entry. 1926 * Should be running at splnet. 1927 */ 1928 static void 1929 ngintr(void) 1930 { 1931 hook_p hook; 1932 struct ng_queue_entry *ngq; 1933 struct mbuf *m; 1934 meta_p meta; 1935 void *retaddr; 1936 struct ng_mesg *msg; 1937 node_p node; 1938 int error = 0; 1939 int s; 1940 1941 while (1) { 1942 s = splhigh(); 1943 if ((ngq = ngqbase)) { 1944 ngqbase = ngq->next; 1945 ngqsize--; 1946 } 1947 splx(s); 1948 if (ngq == NULL) 1949 return; 1950 switch (ngq->flags) { 1951 case NGQF_DATA: 1952 hook = ngq->body.data.da_hook; 1953 m = ngq->body.data.da_m; 1954 meta = ngq->body.data.da_meta; 1955 RETURN_QBLK(ngq); 1956 NG_SEND_DATAQ(error, hook, m, meta); 1957 ng_unref_hook(hook); 1958 break; 1959 case NGQF_MESG: 1960 node = ngq->body.msg.msg_node; 1961 msg = ngq->body.msg.msg_msg; 1962 retaddr = ngq->body.msg.msg_retaddr; 1963 RETURN_QBLK(ngq); 1964 if (node->flags & NG_INVALID) { 1965 FREE(msg, M_NETGRAPH); 1966 } else { 1967 CALL_MSG_HANDLER(error, node, msg, 1968 retaddr, NULL); 1969 } 1970 ng_unref(node); 1971 if (retaddr) 1972 FREE(retaddr, M_NETGRAPH); 1973 break; 1974 default: 1975 RETURN_QBLK(ngq); 1976 } 1977 } 1978 } 1979 1980 1981