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 MODULE_VERSION(netgraph, 1); 67 68 /* List of all nodes */ 69 static LIST_HEAD(, ng_node) nodelist; 70 71 /* List of installed types */ 72 static LIST_HEAD(, ng_type) typelist; 73 74 /* Hash releted definitions */ 75 #define ID_HASH_SIZE 32 /* most systems wont need even this many */ 76 static LIST_HEAD(, ng_node) ID_hash[ID_HASH_SIZE]; 77 /* Don't nead to initialise them because it's a LIST */ 78 79 /* Internal functions */ 80 static int ng_add_hook(node_p node, const char *name, hook_p * hookp); 81 static int ng_connect(hook_p hook1, hook_p hook2); 82 static void ng_disconnect_hook(hook_p hook); 83 static int ng_generic_msg(node_p here, struct ng_mesg *msg, 84 const char *retaddr, struct ng_mesg ** resp, 85 hook_p hook); 86 static ng_ID_t ng_decodeidname(const char *name); 87 static int ngb_mod_event(module_t mod, int event, void *data); 88 static void ngintr(void); 89 90 /* Our own netgraph malloc type */ 91 MALLOC_DEFINE(M_NETGRAPH, "netgraph", "netgraph structures and ctrl messages"); 92 93 /* Set this to Debugger("X") to catch all errors as they occur */ 94 #ifndef TRAP_ERROR 95 #define TRAP_ERROR 96 #endif 97 98 static ng_ID_t nextID = 1; 99 100 #ifdef INVARIANTS 101 #define CHECK_DATA_MBUF(m) do { \ 102 struct mbuf *n; \ 103 int total; \ 104 \ 105 if (((m)->m_flags & M_PKTHDR) == 0) \ 106 panic("%s: !PKTHDR", __FUNCTION__); \ 107 for (total = 0, n = (m); n != NULL; n = n->m_next) \ 108 total += n->m_len; \ 109 if ((m)->m_pkthdr.len != total) { \ 110 panic("%s: %d != %d", \ 111 __FUNCTION__, (m)->m_pkthdr.len, total); \ 112 } \ 113 } while (0) 114 #else 115 #define CHECK_DATA_MBUF(m) 116 #endif 117 118 119 /************************************************************************ 120 Parse type definitions for generic messages 121 ************************************************************************/ 122 123 /* Handy structure parse type defining macro */ 124 #define DEFINE_PARSE_STRUCT_TYPE(lo, up, args) \ 125 static const struct ng_parse_struct_info \ 126 ng_ ## lo ## _type_info = NG_GENERIC_ ## up ## _INFO args; \ 127 static const struct ng_parse_type ng_generic_ ## lo ## _type = { \ 128 &ng_parse_struct_type, \ 129 &ng_ ## lo ## _type_info \ 130 } 131 132 DEFINE_PARSE_STRUCT_TYPE(mkpeer, MKPEER, ()); 133 DEFINE_PARSE_STRUCT_TYPE(connect, CONNECT, ()); 134 DEFINE_PARSE_STRUCT_TYPE(name, NAME, ()); 135 DEFINE_PARSE_STRUCT_TYPE(rmhook, RMHOOK, ()); 136 DEFINE_PARSE_STRUCT_TYPE(nodeinfo, NODEINFO, ()); 137 DEFINE_PARSE_STRUCT_TYPE(typeinfo, TYPEINFO, ()); 138 DEFINE_PARSE_STRUCT_TYPE(linkinfo, LINKINFO, (&ng_generic_nodeinfo_type)); 139 140 /* Get length of an array when the length is stored as a 32 bit 141 value immediately preceeding the array -- as with struct namelist 142 and struct typelist. */ 143 static int 144 ng_generic_list_getLength(const struct ng_parse_type *type, 145 const u_char *start, const u_char *buf) 146 { 147 return *((const u_int32_t *)(buf - 4)); 148 } 149 150 /* Get length of the array of struct linkinfo inside a struct hooklist */ 151 static int 152 ng_generic_linkinfo_getLength(const struct ng_parse_type *type, 153 const u_char *start, const u_char *buf) 154 { 155 const struct hooklist *hl = (const struct hooklist *)start; 156 157 return hl->nodeinfo.hooks; 158 } 159 160 /* Array type for a variable length array of struct namelist */ 161 static const struct ng_parse_array_info ng_nodeinfoarray_type_info = { 162 &ng_generic_nodeinfo_type, 163 &ng_generic_list_getLength 164 }; 165 static const struct ng_parse_type ng_generic_nodeinfoarray_type = { 166 &ng_parse_array_type, 167 &ng_nodeinfoarray_type_info 168 }; 169 170 /* Array type for a variable length array of struct typelist */ 171 static const struct ng_parse_array_info ng_typeinfoarray_type_info = { 172 &ng_generic_typeinfo_type, 173 &ng_generic_list_getLength 174 }; 175 static const struct ng_parse_type ng_generic_typeinfoarray_type = { 176 &ng_parse_array_type, 177 &ng_typeinfoarray_type_info 178 }; 179 180 /* Array type for array of struct linkinfo in struct hooklist */ 181 static const struct ng_parse_array_info ng_generic_linkinfo_array_type_info = { 182 &ng_generic_linkinfo_type, 183 &ng_generic_linkinfo_getLength 184 }; 185 static const struct ng_parse_type ng_generic_linkinfo_array_type = { 186 &ng_parse_array_type, 187 &ng_generic_linkinfo_array_type_info 188 }; 189 190 DEFINE_PARSE_STRUCT_TYPE(typelist, TYPELIST, (&ng_generic_nodeinfoarray_type)); 191 DEFINE_PARSE_STRUCT_TYPE(hooklist, HOOKLIST, 192 (&ng_generic_nodeinfo_type, &ng_generic_linkinfo_array_type)); 193 DEFINE_PARSE_STRUCT_TYPE(listnodes, LISTNODES, 194 (&ng_generic_nodeinfoarray_type)); 195 196 /* List of commands and how to convert arguments to/from ASCII */ 197 static const struct ng_cmdlist ng_generic_cmds[] = { 198 { 199 NGM_GENERIC_COOKIE, 200 NGM_SHUTDOWN, 201 "shutdown", 202 NULL, 203 NULL 204 }, 205 { 206 NGM_GENERIC_COOKIE, 207 NGM_MKPEER, 208 "mkpeer", 209 &ng_generic_mkpeer_type, 210 NULL 211 }, 212 { 213 NGM_GENERIC_COOKIE, 214 NGM_CONNECT, 215 "connect", 216 &ng_generic_connect_type, 217 NULL 218 }, 219 { 220 NGM_GENERIC_COOKIE, 221 NGM_NAME, 222 "name", 223 &ng_generic_name_type, 224 NULL 225 }, 226 { 227 NGM_GENERIC_COOKIE, 228 NGM_RMHOOK, 229 "rmhook", 230 &ng_generic_rmhook_type, 231 NULL 232 }, 233 { 234 NGM_GENERIC_COOKIE, 235 NGM_NODEINFO, 236 "nodeinfo", 237 NULL, 238 &ng_generic_nodeinfo_type 239 }, 240 { 241 NGM_GENERIC_COOKIE, 242 NGM_LISTHOOKS, 243 "listhooks", 244 NULL, 245 &ng_generic_hooklist_type 246 }, 247 { 248 NGM_GENERIC_COOKIE, 249 NGM_LISTNAMES, 250 "listnames", 251 NULL, 252 &ng_generic_listnodes_type /* same as NGM_LISTNODES */ 253 }, 254 { 255 NGM_GENERIC_COOKIE, 256 NGM_LISTNODES, 257 "listnodes", 258 NULL, 259 &ng_generic_listnodes_type 260 }, 261 { 262 NGM_GENERIC_COOKIE, 263 NGM_LISTTYPES, 264 "listtypes", 265 NULL, 266 &ng_generic_typeinfo_type 267 }, 268 { 269 NGM_GENERIC_COOKIE, 270 NGM_TEXT_CONFIG, 271 "textconfig", 272 NULL, 273 &ng_parse_string_type 274 }, 275 { 276 NGM_GENERIC_COOKIE, 277 NGM_TEXT_STATUS, 278 "textstatus", 279 NULL, 280 &ng_parse_string_type 281 }, 282 { 283 NGM_GENERIC_COOKIE, 284 NGM_ASCII2BINARY, 285 "ascii2binary", 286 &ng_parse_ng_mesg_type, 287 &ng_parse_ng_mesg_type 288 }, 289 { 290 NGM_GENERIC_COOKIE, 291 NGM_BINARY2ASCII, 292 "binary2ascii", 293 &ng_parse_ng_mesg_type, 294 &ng_parse_ng_mesg_type 295 }, 296 { 0 } 297 }; 298 299 /************************************************************************ 300 Node routines 301 ************************************************************************/ 302 303 /* 304 * Instantiate a node of the requested type 305 */ 306 int 307 ng_make_node(const char *typename, node_p *nodepp) 308 { 309 struct ng_type *type; 310 311 /* Check that the type makes sense */ 312 if (typename == NULL) { 313 TRAP_ERROR; 314 return (EINVAL); 315 } 316 317 /* Locate the node type */ 318 if ((type = ng_findtype(typename)) == NULL) { 319 char filename[NG_TYPELEN + 4]; 320 linker_file_t lf; 321 int error; 322 323 /* Not found, try to load it as a loadable module */ 324 snprintf(filename, sizeof(filename), "ng_%s", typename); 325 error = linker_load_file(filename, &lf); 326 if (error != 0) 327 return (error); 328 lf->userrefs++; /* pretend loaded by the syscall */ 329 330 /* Try again, as now the type should have linked itself in */ 331 if ((type = ng_findtype(typename)) == NULL) 332 return (ENXIO); 333 } 334 335 /* Call the constructor */ 336 if (type->constructor != NULL) 337 return ((*type->constructor)(nodepp)); 338 else 339 return (ng_make_node_common(type, nodepp)); 340 } 341 342 /* 343 * Generic node creation. Called by node constructors. 344 * The returned node has a reference count of 1. 345 */ 346 int 347 ng_make_node_common(struct ng_type *type, node_p *nodepp) 348 { 349 node_p node; 350 351 /* Require the node type to have been already installed */ 352 if (ng_findtype(type->name) == NULL) { 353 TRAP_ERROR; 354 return (EINVAL); 355 } 356 357 /* Make a node and try attach it to the type */ 358 MALLOC(node, node_p, sizeof(*node), M_NETGRAPH, M_NOWAIT); 359 if (node == NULL) { 360 TRAP_ERROR; 361 return (ENOMEM); 362 } 363 bzero(node, sizeof(*node)); 364 node->type = type; 365 node->refs++; /* note reference */ 366 type->refs++; 367 368 /* Link us into the node linked list */ 369 LIST_INSERT_HEAD(&nodelist, node, nodes); 370 371 /* Initialize hook list for new node */ 372 LIST_INIT(&node->hooks); 373 374 /* get an ID and put us in the hash chain */ 375 node->ID = nextID++; /* 137 per second for 1 year before wrap */ 376 LIST_INSERT_HEAD(&ID_hash[node->ID % ID_HASH_SIZE], node, idnodes); 377 378 /* Done */ 379 *nodepp = node; 380 return (0); 381 } 382 383 /* 384 * Forceably start the shutdown process on a node. Either call 385 * it's shutdown method, or do the default shutdown if there is 386 * no type-specific method. 387 * 388 * Persistent nodes must have a type-specific method which 389 * resets the NG_INVALID flag. 390 */ 391 void 392 ng_rmnode(node_p node) 393 { 394 /* Check if it's already shutting down */ 395 if ((node->flags & NG_INVALID) != 0) 396 return; 397 398 /* Add an extra reference so it doesn't go away during this */ 399 node->refs++; 400 401 /* Mark it invalid so any newcomers know not to try use it */ 402 node->flags |= NG_INVALID; 403 404 /* Ask the type if it has anything to do in this case */ 405 if (node->type && node->type->shutdown) 406 (*node->type->shutdown)(node); 407 else { /* do the default thing */ 408 ng_unname(node); 409 ng_cutlinks(node); 410 ng_unref(node); 411 } 412 413 /* Remove extra reference, possibly the last */ 414 ng_unref(node); 415 } 416 417 /* 418 * Called by the destructor to remove any STANDARD external references 419 */ 420 void 421 ng_cutlinks(node_p node) 422 { 423 hook_p hook; 424 425 /* Make sure that this is set to stop infinite loops */ 426 node->flags |= NG_INVALID; 427 428 /* If we have sleepers, wake them up; they'll see NG_INVALID */ 429 if (node->sleepers) 430 wakeup(node); 431 432 /* Notify all remaining connected nodes to disconnect */ 433 while ((hook = LIST_FIRST(&node->hooks)) != NULL) 434 ng_destroy_hook(hook); 435 } 436 437 /* 438 * Remove a reference to the node, possibly the last 439 */ 440 void 441 ng_unref(node_p node) 442 { 443 if (--node->refs <= 0) { 444 node->type->refs--; 445 LIST_REMOVE(node, nodes); 446 LIST_REMOVE(node, idnodes); 447 FREE(node, M_NETGRAPH); 448 } 449 } 450 451 /* 452 * Wait for a node to come ready. Returns a node with a reference count; 453 * don't forget to drop it when we are done with it using ng_release_node(). 454 */ 455 int 456 ng_wait_node(node_p node, char *msg) 457 { 458 int s, error = 0; 459 460 if (msg == NULL) 461 msg = "netgraph"; 462 s = splnet(); 463 node->sleepers++; 464 node->refs++; /* the sleeping process counts as a reference */ 465 while ((node->flags & (NG_BUSY | NG_INVALID)) == NG_BUSY) 466 error = tsleep(node, (PZERO + 1) | PCATCH, msg, 0); 467 node->sleepers--; 468 if (node->flags & NG_INVALID) { 469 TRAP_ERROR; 470 error = ENXIO; 471 } else { 472 KASSERT(node->refs > 1, 473 ("%s: refs=%d", __FUNCTION__, node->refs)); 474 node->flags |= NG_BUSY; 475 } 476 splx(s); 477 478 /* Release the reference we had on it */ 479 if (error != 0) 480 ng_unref(node); 481 return error; 482 } 483 484 /* 485 * Release a node acquired via ng_wait_node() 486 */ 487 void 488 ng_release_node(node_p node) 489 { 490 /* Declare that we don't want it */ 491 node->flags &= ~NG_BUSY; 492 493 /* If we have sleepers, then wake them up */ 494 if (node->sleepers) 495 wakeup(node); 496 497 /* We also have a reference.. drop it too */ 498 ng_unref(node); 499 } 500 501 /************************************************************************ 502 Node ID handling 503 ************************************************************************/ 504 static node_p 505 ng_ID2node(ng_ID_t ID) 506 { 507 node_p np; 508 LIST_FOREACH(np, &ID_hash[ID % ID_HASH_SIZE], idnodes) { 509 if (np->ID == ID) 510 break; 511 } 512 return(np); 513 } 514 515 ng_ID_t 516 ng_node2ID(node_p node) 517 { 518 return (node->ID); 519 } 520 521 /************************************************************************ 522 Node name handling 523 ************************************************************************/ 524 525 /* 526 * Assign a node a name. Once assigned, the name cannot be changed. 527 */ 528 int 529 ng_name_node(node_p node, const char *name) 530 { 531 int i; 532 533 /* Check the name is valid */ 534 for (i = 0; i < NG_NODELEN + 1; i++) { 535 if (name[i] == '\0' || name[i] == '.' || name[i] == ':') 536 break; 537 } 538 if (i == 0 || name[i] != '\0') { 539 TRAP_ERROR; 540 return (EINVAL); 541 } 542 if (ng_decodeidname(name) != 0) { /* valid IDs not allowed here */ 543 TRAP_ERROR; 544 return (EINVAL); 545 } 546 547 /* Check the node isn't already named */ 548 if (node->name != NULL) { 549 TRAP_ERROR; 550 return (EISCONN); 551 } 552 553 /* Check the name isn't already being used */ 554 if (ng_findname(node, name) != NULL) { 555 TRAP_ERROR; 556 return (EADDRINUSE); 557 } 558 559 /* Allocate space and copy it */ 560 MALLOC(node->name, char *, strlen(name) + 1, M_NETGRAPH, M_NOWAIT); 561 if (node->name == NULL) { 562 TRAP_ERROR; 563 return (ENOMEM); 564 } 565 strcpy(node->name, name); 566 567 /* The name counts as a reference */ 568 node->refs++; 569 return (0); 570 } 571 572 /* 573 * Find a node by absolute name. The name should NOT end with ':' 574 * The name "." means "this node" and "[xxx]" means "the node 575 * with ID (ie, at address) xxx". 576 * 577 * Returns the node if found, else NULL. 578 */ 579 node_p 580 ng_findname(node_p this, const char *name) 581 { 582 node_p node; 583 ng_ID_t temp; 584 585 /* "." means "this node" */ 586 if (strcmp(name, ".") == 0) 587 return(this); 588 589 /* Check for name-by-ID */ 590 if ((temp = ng_decodeidname(name)) != 0) { 591 return (ng_ID2node(temp)); 592 } 593 594 /* Find node by name */ 595 LIST_FOREACH(node, &nodelist, nodes) { 596 if (node->name != NULL && strcmp(node->name, name) == 0) 597 break; 598 } 599 return (node); 600 } 601 602 /* 603 * Decode a ID name, eg. "[f03034de]". Returns 0 if the 604 * string is not valid, otherwise returns the value. 605 */ 606 static ng_ID_t 607 ng_decodeidname(const char *name) 608 { 609 const int len = strlen(name); 610 char *eptr; 611 u_long val; 612 613 /* Check for proper length, brackets, no leading junk */ 614 if (len < 3 || name[0] != '[' || name[len - 1] != ']' 615 || !isxdigit(name[1])) 616 return (0); 617 618 /* Decode number */ 619 val = strtoul(name + 1, &eptr, 16); 620 if (eptr - name != len - 1 || val == ULONG_MAX || val == 0) 621 return ((ng_ID_t)0); 622 return (ng_ID_t)val; 623 } 624 625 /* 626 * Remove a name from a node. This should only be called 627 * when shutting down and removing the node. 628 */ 629 void 630 ng_unname(node_p node) 631 { 632 if (node->name) { 633 FREE(node->name, M_NETGRAPH); 634 node->name = NULL; 635 ng_unref(node); 636 } 637 } 638 639 /************************************************************************ 640 Hook routines 641 642 Names are not optional. Hooks are always connected, except for a 643 brief moment within these routines. 644 645 ************************************************************************/ 646 647 /* 648 * Remove a hook reference 649 */ 650 static void 651 ng_unref_hook(hook_p hook) 652 { 653 if (--hook->refs == 0) 654 FREE(hook, M_NETGRAPH); 655 } 656 657 /* 658 * Add an unconnected hook to a node. Only used internally. 659 */ 660 static int 661 ng_add_hook(node_p node, const char *name, hook_p *hookp) 662 { 663 hook_p hook; 664 int error = 0; 665 666 /* Check that the given name is good */ 667 if (name == NULL) { 668 TRAP_ERROR; 669 return (EINVAL); 670 } 671 if (ng_findhook(node, name) != NULL) { 672 TRAP_ERROR; 673 return (EEXIST); 674 } 675 676 /* Allocate the hook and link it up */ 677 MALLOC(hook, hook_p, sizeof(*hook), M_NETGRAPH, M_NOWAIT); 678 if (hook == NULL) { 679 TRAP_ERROR; 680 return (ENOMEM); 681 } 682 bzero(hook, sizeof(*hook)); 683 hook->refs = 1; 684 hook->flags = HK_INVALID; 685 hook->node = node; 686 node->refs++; /* each hook counts as a reference */ 687 688 /* Check if the node type code has something to say about it */ 689 if (node->type->newhook != NULL) 690 if ((error = (*node->type->newhook)(node, hook, name)) != 0) 691 goto fail; 692 693 /* 694 * The 'type' agrees so far, so go ahead and link it in. 695 * We'll ask again later when we actually connect the hooks. 696 */ 697 LIST_INSERT_HEAD(&node->hooks, hook, hooks); 698 node->numhooks++; 699 700 /* Set hook name */ 701 MALLOC(hook->name, char *, strlen(name) + 1, M_NETGRAPH, M_NOWAIT); 702 if (hook->name == NULL) { 703 error = ENOMEM; 704 LIST_REMOVE(hook, hooks); 705 node->numhooks--; 706 fail: 707 hook->node = NULL; 708 ng_unref(node); 709 ng_unref_hook(hook); /* this frees the hook */ 710 return (error); 711 } 712 strcpy(hook->name, name); 713 if (hookp) 714 *hookp = hook; 715 return (error); 716 } 717 718 /* 719 * Connect a pair of hooks. Only used internally. 720 */ 721 static int 722 ng_connect(hook_p hook1, hook_p hook2) 723 { 724 int error; 725 726 hook1->peer = hook2; 727 hook2->peer = hook1; 728 729 /* Give each node the opportunity to veto the impending connection */ 730 if (hook1->node->type->connect) { 731 if ((error = (*hook1->node->type->connect) (hook1))) { 732 ng_destroy_hook(hook1); /* also zaps hook2 */ 733 return (error); 734 } 735 } 736 if (hook2->node->type->connect) { 737 if ((error = (*hook2->node->type->connect) (hook2))) { 738 ng_destroy_hook(hook2); /* also zaps hook1 */ 739 return (error); 740 } 741 } 742 hook1->flags &= ~HK_INVALID; 743 hook2->flags &= ~HK_INVALID; 744 return (0); 745 } 746 747 /* 748 * Find a hook 749 * 750 * Node types may supply their own optimized routines for finding 751 * hooks. If none is supplied, we just do a linear search. 752 */ 753 hook_p 754 ng_findhook(node_p node, const char *name) 755 { 756 hook_p hook; 757 758 if (node->type->findhook != NULL) 759 return (*node->type->findhook)(node, name); 760 LIST_FOREACH(hook, &node->hooks, hooks) { 761 if (hook->name != NULL && strcmp(hook->name, name) == 0) 762 return (hook); 763 } 764 return (NULL); 765 } 766 767 /* 768 * Destroy a hook 769 * 770 * As hooks are always attached, this really destroys two hooks. 771 * The one given, and the one attached to it. Disconnect the hooks 772 * from each other first. 773 */ 774 void 775 ng_destroy_hook(hook_p hook) 776 { 777 hook_p peer = hook->peer; 778 779 hook->flags |= HK_INVALID; /* as soon as possible */ 780 if (peer) { 781 peer->flags |= HK_INVALID; /* as soon as possible */ 782 hook->peer = NULL; 783 peer->peer = NULL; 784 ng_disconnect_hook(peer); 785 } 786 ng_disconnect_hook(hook); 787 } 788 789 /* 790 * Notify the node of the hook's demise. This may result in more actions 791 * (e.g. shutdown) but we don't do that ourselves and don't know what 792 * happens there. If there is no appropriate handler, then just remove it 793 * (and decrement the reference count of it's node which in turn might 794 * make something happen). 795 */ 796 static void 797 ng_disconnect_hook(hook_p hook) 798 { 799 node_p node = hook->node; 800 801 /* 802 * Remove the hook from the node's list to avoid possible recursion 803 * in case the disconnection results in node shutdown. 804 */ 805 LIST_REMOVE(hook, hooks); 806 node->numhooks--; 807 if (node->type->disconnect) { 808 /* 809 * The type handler may elect to destroy the peer so don't 810 * trust its existance after this point. 811 */ 812 (*node->type->disconnect) (hook); 813 } 814 ng_unref(node); /* might be the last reference */ 815 if (hook->name) 816 FREE(hook->name, M_NETGRAPH); 817 hook->node = NULL; /* may still be referenced elsewhere */ 818 ng_unref_hook(hook); 819 } 820 821 /* 822 * Take two hooks on a node and merge the connection so that the given node 823 * is effectively bypassed. 824 */ 825 int 826 ng_bypass(hook_p hook1, hook_p hook2) 827 { 828 if (hook1->node != hook2->node) 829 return (EINVAL); 830 hook1->peer->peer = hook2->peer; 831 hook2->peer->peer = hook1->peer; 832 833 /* XXX If we ever cache methods on hooks update them as well */ 834 hook1->peer = NULL; 835 hook2->peer = NULL; 836 ng_destroy_hook(hook1); 837 ng_destroy_hook(hook2); 838 return (0); 839 } 840 841 /* 842 * Install a new netgraph type 843 */ 844 int 845 ng_newtype(struct ng_type *tp) 846 { 847 const size_t namelen = strlen(tp->name); 848 849 /* Check version and type name fields */ 850 if (tp->version != NG_VERSION || namelen == 0 || namelen > NG_TYPELEN) { 851 TRAP_ERROR; 852 return (EINVAL); 853 } 854 855 /* Check for name collision */ 856 if (ng_findtype(tp->name) != NULL) { 857 TRAP_ERROR; 858 return (EEXIST); 859 } 860 861 /* Link in new type */ 862 LIST_INSERT_HEAD(&typelist, tp, types); 863 tp->refs = 0; 864 return (0); 865 } 866 867 /* 868 * Look for a type of the name given 869 */ 870 struct ng_type * 871 ng_findtype(const char *typename) 872 { 873 struct ng_type *type; 874 875 LIST_FOREACH(type, &typelist, types) { 876 if (strcmp(type->name, typename) == 0) 877 break; 878 } 879 return (type); 880 } 881 882 883 /************************************************************************ 884 Composite routines 885 ************************************************************************/ 886 887 /* 888 * Make a peer and connect. The order is arranged to minimise 889 * the work needed to back out in case of error. 890 */ 891 int 892 ng_mkpeer(node_p node, const char *name, const char *name2, char *type) 893 { 894 node_p node2; 895 hook_p hook; 896 hook_p hook2; 897 int error; 898 899 if ((error = ng_add_hook(node, name, &hook))) 900 return (error); 901 if ((error = ng_make_node(type, &node2))) { 902 ng_destroy_hook(hook); 903 return (error); 904 } 905 if ((error = ng_add_hook(node2, name2, &hook2))) { 906 ng_rmnode(node2); 907 ng_destroy_hook(hook); 908 return (error); 909 } 910 911 /* 912 * Actually link the two hooks together.. on failure they are 913 * destroyed so we don't have to do that here. 914 */ 915 if ((error = ng_connect(hook, hook2))) 916 ng_rmnode(node2); 917 return (error); 918 } 919 920 /* 921 * Connect two nodes using the specified hooks 922 */ 923 int 924 ng_con_nodes(node_p node, const char *name, node_p node2, const char *name2) 925 { 926 int error; 927 hook_p hook; 928 hook_p hook2; 929 930 if ((error = ng_add_hook(node, name, &hook))) 931 return (error); 932 if ((error = ng_add_hook(node2, name2, &hook2))) { 933 ng_destroy_hook(hook); 934 return (error); 935 } 936 return (ng_connect(hook, hook2)); 937 } 938 939 /* 940 * Parse and verify a string of the form: <NODE:><PATH> 941 * 942 * Such a string can refer to a specific node or a specific hook 943 * on a specific node, depending on how you look at it. In the 944 * latter case, the PATH component must not end in a dot. 945 * 946 * Both <NODE:> and <PATH> are optional. The <PATH> is a string 947 * of hook names separated by dots. This breaks out the original 948 * string, setting *nodep to "NODE" (or NULL if none) and *pathp 949 * to "PATH" (or NULL if degenerate). Also, *hookp will point to 950 * the final hook component of <PATH>, if any, otherwise NULL. 951 * 952 * This returns -1 if the path is malformed. The char ** are optional. 953 */ 954 955 int 956 ng_path_parse(char *addr, char **nodep, char **pathp, char **hookp) 957 { 958 char *node, *path, *hook; 959 int k; 960 961 /* 962 * Extract absolute NODE, if any 963 */ 964 for (path = addr; *path && *path != ':'; path++); 965 if (*path) { 966 node = addr; /* Here's the NODE */ 967 *path++ = '\0'; /* Here's the PATH */ 968 969 /* Node name must not be empty */ 970 if (!*node) 971 return -1; 972 973 /* A name of "." is OK; otherwise '.' not allowed */ 974 if (strcmp(node, ".") != 0) { 975 for (k = 0; node[k]; k++) 976 if (node[k] == '.') 977 return -1; 978 } 979 } else { 980 node = NULL; /* No absolute NODE */ 981 path = addr; /* Here's the PATH */ 982 } 983 984 /* Snoop for illegal characters in PATH */ 985 for (k = 0; path[k]; k++) 986 if (path[k] == ':') 987 return -1; 988 989 /* Check for no repeated dots in PATH */ 990 for (k = 0; path[k]; k++) 991 if (path[k] == '.' && path[k + 1] == '.') 992 return -1; 993 994 /* Remove extra (degenerate) dots from beginning or end of PATH */ 995 if (path[0] == '.') 996 path++; 997 if (*path && path[strlen(path) - 1] == '.') 998 path[strlen(path) - 1] = 0; 999 1000 /* If PATH has a dot, then we're not talking about a hook */ 1001 if (*path) { 1002 for (hook = path, k = 0; path[k]; k++) 1003 if (path[k] == '.') { 1004 hook = NULL; 1005 break; 1006 } 1007 } else 1008 path = hook = NULL; 1009 1010 /* Done */ 1011 if (nodep) 1012 *nodep = node; 1013 if (pathp) 1014 *pathp = path; 1015 if (hookp) 1016 *hookp = hook; 1017 return (0); 1018 } 1019 1020 /* 1021 * Given a path, which may be absolute or relative, and a starting node, 1022 * return the destination node. Compute the "return address" if desired. 1023 */ 1024 int 1025 ng_path2node(node_p here, const char *address, node_p *destp, char **rtnp, 1026 hook_p *lasthook) 1027 { 1028 const node_p start = here; 1029 char fullpath[NG_PATHLEN + 1]; 1030 char *nodename, *path, pbuf[2]; 1031 node_p node; 1032 char *cp; 1033 hook_p hook = NULL; 1034 1035 /* Initialize */ 1036 if (rtnp) 1037 *rtnp = NULL; 1038 if (destp == NULL) 1039 return EINVAL; 1040 *destp = NULL; 1041 1042 /* Make a writable copy of address for ng_path_parse() */ 1043 strncpy(fullpath, address, sizeof(fullpath) - 1); 1044 fullpath[sizeof(fullpath) - 1] = '\0'; 1045 1046 /* Parse out node and sequence of hooks */ 1047 if (ng_path_parse(fullpath, &nodename, &path, NULL) < 0) { 1048 TRAP_ERROR; 1049 return EINVAL; 1050 } 1051 if (path == NULL) { 1052 pbuf[0] = '.'; /* Needs to be writable */ 1053 pbuf[1] = '\0'; 1054 path = pbuf; 1055 } 1056 1057 /* For an absolute address, jump to the starting node */ 1058 if (nodename) { 1059 node = ng_findname(here, nodename); 1060 if (node == NULL) { 1061 TRAP_ERROR; 1062 return (ENOENT); 1063 } 1064 } else 1065 node = here; 1066 1067 /* Now follow the sequence of hooks */ 1068 for (cp = path; node != NULL && *cp != '\0'; ) { 1069 char *segment; 1070 1071 /* 1072 * Break out the next path segment. Replace the dot we just 1073 * found with a NUL; "cp" points to the next segment (or the 1074 * NUL at the end). 1075 */ 1076 for (segment = cp; *cp != '\0'; cp++) { 1077 if (*cp == '.') { 1078 *cp++ = '\0'; 1079 break; 1080 } 1081 } 1082 1083 /* Empty segment */ 1084 if (*segment == '\0') 1085 continue; 1086 1087 /* We have a segment, so look for a hook by that name */ 1088 hook = ng_findhook(node, segment); 1089 1090 /* Can't get there from here... */ 1091 if (hook == NULL 1092 || hook->peer == NULL 1093 || (hook->flags & HK_INVALID) != 0) { 1094 TRAP_ERROR; 1095 return (ENOENT); 1096 } 1097 1098 /* Hop on over to the next node */ 1099 node = hook->peer->node; 1100 } 1101 1102 /* If node somehow missing, fail here (probably this is not needed) */ 1103 if (node == NULL) { 1104 TRAP_ERROR; 1105 return (ENXIO); 1106 } 1107 1108 /* Now compute return address, i.e., the path to the sender */ 1109 if (rtnp != NULL) { 1110 MALLOC(*rtnp, char *, NG_NODELEN + 2, M_NETGRAPH, M_NOWAIT); 1111 if (*rtnp == NULL) { 1112 TRAP_ERROR; 1113 return (ENOMEM); 1114 } 1115 if (start->name != NULL) 1116 sprintf(*rtnp, "%s:", start->name); 1117 else 1118 sprintf(*rtnp, "[%x]:", ng_node2ID(start)); 1119 } 1120 1121 /* Done */ 1122 *destp = node; 1123 if (lasthook != NULL) 1124 *lasthook = hook ? hook->peer : NULL; 1125 return (0); 1126 } 1127 1128 /* 1129 * Call the appropriate message handler for the object. 1130 * It is up to the message handler to free the message. 1131 * If it's a generic message, handle it generically, otherwise 1132 * call the type's message handler (if it exists) 1133 */ 1134 1135 #define CALL_MSG_HANDLER(error, node, msg, retaddr, resp, hook) \ 1136 do { \ 1137 if((msg)->header.typecookie == NGM_GENERIC_COOKIE) { \ 1138 (error) = ng_generic_msg((node), (msg), \ 1139 (retaddr), (resp), (hook)); \ 1140 } else { \ 1141 if ((node)->type->rcvmsg != NULL) { \ 1142 (error) = (*(node)->type->rcvmsg)((node), \ 1143 (msg), (retaddr), (resp), (hook)); \ 1144 } else { \ 1145 TRAP_ERROR; \ 1146 FREE((msg), M_NETGRAPH); \ 1147 (error) = EINVAL; \ 1148 } \ 1149 } \ 1150 } while (0) 1151 1152 1153 /* 1154 * Send a control message to a node 1155 */ 1156 int 1157 ng_send_msg(node_p here, struct ng_mesg *msg, const char *address, 1158 struct ng_mesg **rptr) 1159 { 1160 node_p dest = NULL; 1161 char *retaddr = NULL; 1162 int error; 1163 hook_p lasthook; 1164 1165 /* Find the target node */ 1166 error = ng_path2node(here, address, &dest, &retaddr, &lasthook); 1167 if (error) { 1168 FREE(msg, M_NETGRAPH); 1169 return error; 1170 } 1171 1172 /* Make sure the resp field is null before we start */ 1173 if (rptr != NULL) 1174 *rptr = NULL; 1175 1176 CALL_MSG_HANDLER(error, dest, msg, retaddr, rptr, lasthook); 1177 1178 /* Make sure that if there is a response, it has the RESP bit set */ 1179 if ((error == 0) && rptr && *rptr) 1180 (*rptr)->header.flags |= NGF_RESP; 1181 1182 /* 1183 * If we had a return address it is up to us to free it. They should 1184 * have taken a copy if they needed to make a delayed response. 1185 */ 1186 if (retaddr) 1187 FREE(retaddr, M_NETGRAPH); 1188 return (error); 1189 } 1190 1191 /* 1192 * Implement the 'generic' control messages 1193 */ 1194 static int 1195 ng_generic_msg(node_p here, struct ng_mesg *msg, const char *retaddr, 1196 struct ng_mesg **resp, hook_p lasthook) 1197 { 1198 int error = 0; 1199 1200 if (msg->header.typecookie != NGM_GENERIC_COOKIE) { 1201 TRAP_ERROR; 1202 FREE(msg, M_NETGRAPH); 1203 return (EINVAL); 1204 } 1205 switch (msg->header.cmd) { 1206 case NGM_SHUTDOWN: 1207 ng_rmnode(here); 1208 break; 1209 case NGM_MKPEER: 1210 { 1211 struct ngm_mkpeer *const mkp = (struct ngm_mkpeer *) msg->data; 1212 1213 if (msg->header.arglen != sizeof(*mkp)) { 1214 TRAP_ERROR; 1215 return (EINVAL); 1216 } 1217 mkp->type[sizeof(mkp->type) - 1] = '\0'; 1218 mkp->ourhook[sizeof(mkp->ourhook) - 1] = '\0'; 1219 mkp->peerhook[sizeof(mkp->peerhook) - 1] = '\0'; 1220 error = ng_mkpeer(here, mkp->ourhook, mkp->peerhook, mkp->type); 1221 break; 1222 } 1223 case NGM_CONNECT: 1224 { 1225 struct ngm_connect *const con = 1226 (struct ngm_connect *) msg->data; 1227 node_p node2; 1228 1229 if (msg->header.arglen != sizeof(*con)) { 1230 TRAP_ERROR; 1231 return (EINVAL); 1232 } 1233 con->path[sizeof(con->path) - 1] = '\0'; 1234 con->ourhook[sizeof(con->ourhook) - 1] = '\0'; 1235 con->peerhook[sizeof(con->peerhook) - 1] = '\0'; 1236 error = ng_path2node(here, con->path, &node2, NULL, NULL); 1237 if (error) 1238 break; 1239 error = ng_con_nodes(here, con->ourhook, node2, con->peerhook); 1240 break; 1241 } 1242 case NGM_NAME: 1243 { 1244 struct ngm_name *const nam = (struct ngm_name *) msg->data; 1245 1246 if (msg->header.arglen != sizeof(*nam)) { 1247 TRAP_ERROR; 1248 return (EINVAL); 1249 } 1250 nam->name[sizeof(nam->name) - 1] = '\0'; 1251 error = ng_name_node(here, nam->name); 1252 break; 1253 } 1254 case NGM_RMHOOK: 1255 { 1256 struct ngm_rmhook *const rmh = (struct ngm_rmhook *) msg->data; 1257 hook_p hook; 1258 1259 if (msg->header.arglen != sizeof(*rmh)) { 1260 TRAP_ERROR; 1261 return (EINVAL); 1262 } 1263 rmh->ourhook[sizeof(rmh->ourhook) - 1] = '\0'; 1264 if ((hook = ng_findhook(here, rmh->ourhook)) != NULL) 1265 ng_destroy_hook(hook); 1266 break; 1267 } 1268 case NGM_NODEINFO: 1269 { 1270 struct nodeinfo *ni; 1271 struct ng_mesg *rp; 1272 1273 /* Get response struct */ 1274 if (resp == NULL) { 1275 error = EINVAL; 1276 break; 1277 } 1278 NG_MKRESPONSE(rp, msg, sizeof(*ni), M_NOWAIT); 1279 if (rp == NULL) { 1280 error = ENOMEM; 1281 break; 1282 } 1283 1284 /* Fill in node info */ 1285 ni = (struct nodeinfo *) rp->data; 1286 if (here->name != NULL) 1287 strncpy(ni->name, here->name, NG_NODELEN); 1288 strncpy(ni->type, here->type->name, NG_TYPELEN); 1289 ni->id = ng_node2ID(here); 1290 ni->hooks = here->numhooks; 1291 *resp = rp; 1292 break; 1293 } 1294 case NGM_LISTHOOKS: 1295 { 1296 const int nhooks = here->numhooks; 1297 struct hooklist *hl; 1298 struct nodeinfo *ni; 1299 struct ng_mesg *rp; 1300 hook_p hook; 1301 1302 /* Get response struct */ 1303 if (resp == NULL) { 1304 error = EINVAL; 1305 break; 1306 } 1307 NG_MKRESPONSE(rp, msg, sizeof(*hl) 1308 + (nhooks * sizeof(struct linkinfo)), M_NOWAIT); 1309 if (rp == NULL) { 1310 error = ENOMEM; 1311 break; 1312 } 1313 hl = (struct hooklist *) rp->data; 1314 ni = &hl->nodeinfo; 1315 1316 /* Fill in node info */ 1317 if (here->name) 1318 strncpy(ni->name, here->name, NG_NODELEN); 1319 strncpy(ni->type, here->type->name, NG_TYPELEN); 1320 ni->id = ng_node2ID(here); 1321 1322 /* Cycle through the linked list of hooks */ 1323 ni->hooks = 0; 1324 LIST_FOREACH(hook, &here->hooks, hooks) { 1325 struct linkinfo *const link = &hl->link[ni->hooks]; 1326 1327 if (ni->hooks >= nhooks) { 1328 log(LOG_ERR, "%s: number of %s changed\n", 1329 __FUNCTION__, "hooks"); 1330 break; 1331 } 1332 if ((hook->flags & HK_INVALID) != 0) 1333 continue; 1334 strncpy(link->ourhook, hook->name, NG_HOOKLEN); 1335 strncpy(link->peerhook, hook->peer->name, NG_HOOKLEN); 1336 if (hook->peer->node->name != NULL) 1337 strncpy(link->nodeinfo.name, 1338 hook->peer->node->name, NG_NODELEN); 1339 strncpy(link->nodeinfo.type, 1340 hook->peer->node->type->name, NG_TYPELEN); 1341 link->nodeinfo.id = ng_node2ID(hook->peer->node); 1342 link->nodeinfo.hooks = hook->peer->node->numhooks; 1343 ni->hooks++; 1344 } 1345 *resp = rp; 1346 break; 1347 } 1348 1349 case NGM_LISTNAMES: 1350 case NGM_LISTNODES: 1351 { 1352 const int unnamed = (msg->header.cmd == NGM_LISTNODES); 1353 struct namelist *nl; 1354 struct ng_mesg *rp; 1355 node_p node; 1356 int num = 0; 1357 1358 if (resp == NULL) { 1359 error = EINVAL; 1360 break; 1361 } 1362 1363 /* Count number of nodes */ 1364 LIST_FOREACH(node, &nodelist, nodes) { 1365 if (unnamed || node->name != NULL) 1366 num++; 1367 } 1368 1369 /* Get response struct */ 1370 if (resp == NULL) { 1371 error = EINVAL; 1372 break; 1373 } 1374 NG_MKRESPONSE(rp, msg, sizeof(*nl) 1375 + (num * sizeof(struct nodeinfo)), M_NOWAIT); 1376 if (rp == NULL) { 1377 error = ENOMEM; 1378 break; 1379 } 1380 nl = (struct namelist *) rp->data; 1381 1382 /* Cycle through the linked list of nodes */ 1383 nl->numnames = 0; 1384 LIST_FOREACH(node, &nodelist, nodes) { 1385 struct nodeinfo *const np = &nl->nodeinfo[nl->numnames]; 1386 1387 if (nl->numnames >= num) { 1388 log(LOG_ERR, "%s: number of %s changed\n", 1389 __FUNCTION__, "nodes"); 1390 break; 1391 } 1392 if ((node->flags & NG_INVALID) != 0) 1393 continue; 1394 if (!unnamed && node->name == NULL) 1395 continue; 1396 if (node->name != NULL) 1397 strncpy(np->name, node->name, NG_NODELEN); 1398 strncpy(np->type, node->type->name, NG_TYPELEN); 1399 np->id = ng_node2ID(node); 1400 np->hooks = node->numhooks; 1401 nl->numnames++; 1402 } 1403 *resp = rp; 1404 break; 1405 } 1406 1407 case NGM_LISTTYPES: 1408 { 1409 struct typelist *tl; 1410 struct ng_mesg *rp; 1411 struct ng_type *type; 1412 int num = 0; 1413 1414 if (resp == NULL) { 1415 error = EINVAL; 1416 break; 1417 } 1418 1419 /* Count number of types */ 1420 LIST_FOREACH(type, &typelist, types) 1421 num++; 1422 1423 /* Get response struct */ 1424 if (resp == NULL) { 1425 error = EINVAL; 1426 break; 1427 } 1428 NG_MKRESPONSE(rp, msg, sizeof(*tl) 1429 + (num * sizeof(struct typeinfo)), M_NOWAIT); 1430 if (rp == NULL) { 1431 error = ENOMEM; 1432 break; 1433 } 1434 tl = (struct typelist *) rp->data; 1435 1436 /* Cycle through the linked list of types */ 1437 tl->numtypes = 0; 1438 LIST_FOREACH(type, &typelist, types) { 1439 struct typeinfo *const tp = &tl->typeinfo[tl->numtypes]; 1440 1441 if (tl->numtypes >= num) { 1442 log(LOG_ERR, "%s: number of %s changed\n", 1443 __FUNCTION__, "types"); 1444 break; 1445 } 1446 strncpy(tp->type_name, type->name, NG_TYPELEN); 1447 tp->numnodes = type->refs; 1448 tl->numtypes++; 1449 } 1450 *resp = rp; 1451 break; 1452 } 1453 1454 case NGM_BINARY2ASCII: 1455 { 1456 int bufSize = 2000; /* XXX hard coded constant */ 1457 const struct ng_parse_type *argstype; 1458 const struct ng_cmdlist *c; 1459 struct ng_mesg *rp, *binary, *ascii; 1460 1461 /* Data area must contain a valid netgraph message */ 1462 binary = (struct ng_mesg *)msg->data; 1463 if (msg->header.arglen < sizeof(struct ng_mesg) 1464 || msg->header.arglen - sizeof(struct ng_mesg) 1465 < binary->header.arglen) { 1466 error = EINVAL; 1467 break; 1468 } 1469 1470 /* Get a response message with lots of room */ 1471 NG_MKRESPONSE(rp, msg, sizeof(*ascii) + bufSize, M_NOWAIT); 1472 if (rp == NULL) { 1473 error = ENOMEM; 1474 break; 1475 } 1476 ascii = (struct ng_mesg *)rp->data; 1477 1478 /* Copy binary message header to response message payload */ 1479 bcopy(binary, ascii, sizeof(*binary)); 1480 1481 /* Find command by matching typecookie and command number */ 1482 for (c = here->type->cmdlist; 1483 c != NULL && c->name != NULL; c++) { 1484 if (binary->header.typecookie == c->cookie 1485 && binary->header.cmd == c->cmd) 1486 break; 1487 } 1488 if (c == NULL || c->name == NULL) { 1489 for (c = ng_generic_cmds; c->name != NULL; c++) { 1490 if (binary->header.typecookie == c->cookie 1491 && binary->header.cmd == c->cmd) 1492 break; 1493 } 1494 if (c->name == NULL) { 1495 FREE(rp, M_NETGRAPH); 1496 error = ENOSYS; 1497 break; 1498 } 1499 } 1500 1501 /* Convert command name to ASCII */ 1502 snprintf(ascii->header.cmdstr, sizeof(ascii->header.cmdstr), 1503 "%s", c->name); 1504 1505 /* Convert command arguments to ASCII */ 1506 argstype = (binary->header.flags & NGF_RESP) ? 1507 c->respType : c->mesgType; 1508 if (argstype == NULL) 1509 *ascii->data = '\0'; 1510 else { 1511 if ((error = ng_unparse(argstype, 1512 (u_char *)binary->data, 1513 ascii->data, bufSize)) != 0) { 1514 FREE(rp, M_NETGRAPH); 1515 break; 1516 } 1517 } 1518 1519 /* Return the result as struct ng_mesg plus ASCII string */ 1520 bufSize = strlen(ascii->data) + 1; 1521 ascii->header.arglen = bufSize; 1522 rp->header.arglen = sizeof(*ascii) + bufSize; 1523 *resp = rp; 1524 break; 1525 } 1526 1527 case NGM_ASCII2BINARY: 1528 { 1529 int bufSize = 2000; /* XXX hard coded constant */ 1530 const struct ng_cmdlist *c; 1531 const struct ng_parse_type *argstype; 1532 struct ng_mesg *rp, *ascii, *binary; 1533 int off = 0; 1534 1535 /* Data area must contain at least a struct ng_mesg + '\0' */ 1536 ascii = (struct ng_mesg *)msg->data; 1537 if (msg->header.arglen < sizeof(*ascii) + 1 1538 || ascii->header.arglen < 1 1539 || msg->header.arglen 1540 < sizeof(*ascii) + ascii->header.arglen) { 1541 error = EINVAL; 1542 break; 1543 } 1544 ascii->data[ascii->header.arglen - 1] = '\0'; 1545 1546 /* Get a response message with lots of room */ 1547 NG_MKRESPONSE(rp, msg, sizeof(*binary) + bufSize, M_NOWAIT); 1548 if (rp == NULL) { 1549 error = ENOMEM; 1550 break; 1551 } 1552 binary = (struct ng_mesg *)rp->data; 1553 1554 /* Copy ASCII message header to response message payload */ 1555 bcopy(ascii, binary, sizeof(*ascii)); 1556 1557 /* Find command by matching ASCII command string */ 1558 for (c = here->type->cmdlist; 1559 c != NULL && c->name != NULL; c++) { 1560 if (strcmp(ascii->header.cmdstr, c->name) == 0) 1561 break; 1562 } 1563 if (c == NULL || c->name == NULL) { 1564 for (c = ng_generic_cmds; c->name != NULL; c++) { 1565 if (strcmp(ascii->header.cmdstr, c->name) == 0) 1566 break; 1567 } 1568 if (c->name == NULL) { 1569 FREE(rp, M_NETGRAPH); 1570 error = ENOSYS; 1571 break; 1572 } 1573 } 1574 1575 /* Convert command name to binary */ 1576 binary->header.cmd = c->cmd; 1577 binary->header.typecookie = c->cookie; 1578 1579 /* Convert command arguments to binary */ 1580 argstype = (binary->header.flags & NGF_RESP) ? 1581 c->respType : c->mesgType; 1582 if (argstype == NULL) 1583 bufSize = 0; 1584 else { 1585 if ((error = ng_parse(argstype, ascii->data, 1586 &off, (u_char *)binary->data, &bufSize)) != 0) { 1587 FREE(rp, M_NETGRAPH); 1588 break; 1589 } 1590 } 1591 1592 /* Return the result */ 1593 binary->header.arglen = bufSize; 1594 rp->header.arglen = sizeof(*binary) + bufSize; 1595 *resp = rp; 1596 break; 1597 } 1598 1599 case NGM_TEXT_CONFIG: 1600 case NGM_TEXT_STATUS: 1601 /* 1602 * This one is tricky as it passes the command down to the 1603 * actual node, even though it is a generic type command. 1604 * This means we must assume that the msg is already freed 1605 * when control passes back to us. 1606 */ 1607 if (resp == NULL) { 1608 error = EINVAL; 1609 break; 1610 } 1611 if (here->type->rcvmsg != NULL) 1612 return((*here->type->rcvmsg)(here, msg, retaddr, 1613 resp, lasthook)); 1614 /* Fall through if rcvmsg not supported */ 1615 default: 1616 TRAP_ERROR; 1617 error = EINVAL; 1618 } 1619 FREE(msg, M_NETGRAPH); 1620 return (error); 1621 } 1622 1623 /* 1624 * Send a data packet to a node. If the recipient has no 1625 * 'receive data' method, then silently discard the packet. 1626 */ 1627 int 1628 ng_send_data(hook_p hook, struct mbuf *m, meta_p meta, 1629 struct mbuf **ret_m, meta_p *ret_meta) 1630 { 1631 ng_rcvdata_t *rcvdata; 1632 int error; 1633 1634 CHECK_DATA_MBUF(m); 1635 if (hook && (hook->flags & HK_INVALID) == 0) { 1636 rcvdata = hook->peer->node->type->rcvdata; 1637 if (rcvdata != NULL) 1638 error = (*rcvdata)(hook->peer, m, meta, 1639 ret_m, ret_meta); 1640 else { 1641 error = 0; 1642 NG_FREE_DATA(m, meta); 1643 } 1644 } else { 1645 TRAP_ERROR; 1646 error = ENOTCONN; 1647 NG_FREE_DATA(m, meta); 1648 } 1649 return (error); 1650 } 1651 1652 /* 1653 * Send a queued data packet to a node. If the recipient has no 1654 * 'receive queued data' method, then try the 'receive data' method above. 1655 */ 1656 int 1657 ng_send_dataq(hook_p hook, struct mbuf *m, meta_p meta, 1658 struct mbuf **ret_m, meta_p *ret_meta) 1659 { 1660 ng_rcvdata_t *rcvdata; 1661 int error; 1662 1663 CHECK_DATA_MBUF(m); 1664 if (hook && (hook->flags & HK_INVALID) == 0) { 1665 rcvdata = hook->peer->node->type->rcvdataq; 1666 if (rcvdata != NULL) 1667 error = (*rcvdata)(hook->peer, m, meta, 1668 ret_m, ret_meta); 1669 else { 1670 rcvdata = hook->peer->node->type->rcvdata; 1671 if (rcvdata != NULL) { 1672 error = (*rcvdata)(hook->peer, m, meta, 1673 ret_m, ret_meta); 1674 } else { 1675 error = 0; 1676 NG_FREE_DATA(m, meta); 1677 } 1678 } 1679 } else { 1680 TRAP_ERROR; 1681 error = ENOTCONN; 1682 NG_FREE_DATA(m, meta); 1683 } 1684 return (error); 1685 } 1686 1687 /* 1688 * Copy a 'meta'. 1689 * 1690 * Returns new meta, or NULL if original meta is NULL or ENOMEM. 1691 */ 1692 meta_p 1693 ng_copy_meta(meta_p meta) 1694 { 1695 meta_p meta2; 1696 1697 if (meta == NULL) 1698 return (NULL); 1699 MALLOC(meta2, meta_p, meta->used_len, M_NETGRAPH, M_NOWAIT); 1700 if (meta2 == NULL) 1701 return (NULL); 1702 meta2->allocated_len = meta->used_len; 1703 bcopy(meta, meta2, meta->used_len); 1704 return (meta2); 1705 } 1706 1707 /************************************************************************ 1708 Module routines 1709 ************************************************************************/ 1710 1711 /* 1712 * Handle the loading/unloading of a netgraph node type module 1713 */ 1714 int 1715 ng_mod_event(module_t mod, int event, void *data) 1716 { 1717 struct ng_type *const type = data; 1718 int s, error = 0; 1719 1720 switch (event) { 1721 case MOD_LOAD: 1722 1723 /* Register new netgraph node type */ 1724 s = splnet(); 1725 if ((error = ng_newtype(type)) != 0) { 1726 splx(s); 1727 break; 1728 } 1729 1730 /* Call type specific code */ 1731 if (type->mod_event != NULL) 1732 if ((error = (*type->mod_event)(mod, event, data)) != 0) 1733 LIST_REMOVE(type, types); 1734 splx(s); 1735 break; 1736 1737 case MOD_UNLOAD: 1738 s = splnet(); 1739 if (type->refs != 0) /* make sure no nodes exist! */ 1740 error = EBUSY; 1741 else { 1742 if (type->mod_event != NULL) { /* check with type */ 1743 error = (*type->mod_event)(mod, event, data); 1744 if (error != 0) { /* type refuses.. */ 1745 splx(s); 1746 break; 1747 } 1748 } 1749 LIST_REMOVE(type, types); 1750 } 1751 splx(s); 1752 break; 1753 1754 default: 1755 if (type->mod_event != NULL) 1756 error = (*type->mod_event)(mod, event, data); 1757 else 1758 error = 0; /* XXX ? */ 1759 break; 1760 } 1761 return (error); 1762 } 1763 1764 /* 1765 * Handle loading and unloading for this code. 1766 * The only thing we need to link into is the NETISR strucure. 1767 */ 1768 static int 1769 ngb_mod_event(module_t mod, int event, void *data) 1770 { 1771 int s, error = 0; 1772 1773 switch (event) { 1774 case MOD_LOAD: 1775 /* Register line discipline */ 1776 s = splimp(); 1777 error = register_netisr(NETISR_NETGRAPH, ngintr); 1778 splx(s); 1779 break; 1780 case MOD_UNLOAD: 1781 /* You cant unload it because an interface may be using it. */ 1782 error = EBUSY; 1783 break; 1784 default: 1785 error = EOPNOTSUPP; 1786 break; 1787 } 1788 return (error); 1789 } 1790 1791 static moduledata_t netgraph_mod = { 1792 "netgraph", 1793 ngb_mod_event, 1794 (NULL) 1795 }; 1796 DECLARE_MODULE(netgraph, netgraph_mod, SI_SUB_DRIVERS, SI_ORDER_MIDDLE); 1797 1798 /************************************************************************ 1799 Queueing routines 1800 ************************************************************************/ 1801 1802 /* The structure for queueing across ISR switches */ 1803 struct ng_queue_entry { 1804 u_long flags; 1805 struct ng_queue_entry *next; 1806 union { 1807 struct { 1808 hook_p da_hook; /* target hook */ 1809 struct mbuf *da_m; 1810 meta_p da_meta; 1811 } data; 1812 struct { 1813 struct ng_mesg *msg_msg; 1814 node_p msg_node; 1815 void *msg_retaddr; 1816 hook_p msg_lasthook; 1817 } msg; 1818 } body; 1819 }; 1820 #define NGQF_DATA 0x01 /* the queue element is data */ 1821 #define NGQF_MESG 0x02 /* the queue element is a message */ 1822 1823 static struct ng_queue_entry *ngqbase; /* items to be unqueued */ 1824 static struct ng_queue_entry *ngqlast; /* last item queued */ 1825 static const int ngqroom = 64; /* max items to queue */ 1826 static int ngqsize; /* number of items in queue */ 1827 1828 static struct ng_queue_entry *ngqfree; /* free ones */ 1829 static const int ngqfreemax = 16;/* cache at most this many */ 1830 static int ngqfreesize; /* number of cached entries */ 1831 1832 /* 1833 * Get a queue entry 1834 */ 1835 static struct ng_queue_entry * 1836 ng_getqblk(void) 1837 { 1838 register struct ng_queue_entry *q; 1839 int s; 1840 1841 /* Could be guarding against tty ints or whatever */ 1842 s = splhigh(); 1843 1844 /* Try get a cached queue block, or else allocate a new one */ 1845 if ((q = ngqfree) == NULL) { 1846 splx(s); 1847 if (ngqsize < ngqroom) { /* don't worry about races */ 1848 MALLOC(q, struct ng_queue_entry *, 1849 sizeof(*q), M_NETGRAPH, M_NOWAIT); 1850 } 1851 } else { 1852 ngqfree = q->next; 1853 ngqfreesize--; 1854 splx(s); 1855 } 1856 return (q); 1857 } 1858 1859 /* 1860 * Release a queue entry 1861 */ 1862 #define RETURN_QBLK(q) \ 1863 do { \ 1864 int s; \ 1865 if (ngqfreesize < ngqfreemax) { /* don't worry about races */ \ 1866 s = splhigh(); \ 1867 (q)->next = ngqfree; \ 1868 ngqfree = (q); \ 1869 ngqfreesize++; \ 1870 splx(s); \ 1871 } else { \ 1872 FREE((q), M_NETGRAPH); \ 1873 } \ 1874 } while (0) 1875 1876 /* 1877 * Running at a raised (but we don't know which) processor priority level, 1878 * put the data onto a queue to be picked up by another PPL (probably splnet) 1879 */ 1880 int 1881 ng_queue_data(hook_p hook, struct mbuf *m, meta_p meta) 1882 { 1883 struct ng_queue_entry *q; 1884 int s; 1885 1886 if (hook == NULL) { 1887 NG_FREE_DATA(m, meta); 1888 return (0); 1889 } 1890 if ((q = ng_getqblk()) == NULL) { 1891 NG_FREE_DATA(m, meta); 1892 return (ENOBUFS); 1893 } 1894 1895 /* Fill out the contents */ 1896 q->flags = NGQF_DATA; 1897 q->next = NULL; 1898 q->body.data.da_hook = hook; 1899 q->body.data.da_m = m; 1900 q->body.data.da_meta = meta; 1901 hook->refs++; /* don't let it go away while on the queue */ 1902 1903 /* Put it on the queue */ 1904 s = splhigh(); 1905 if (ngqbase) { 1906 ngqlast->next = q; 1907 } else { 1908 ngqbase = q; 1909 } 1910 ngqlast = q; 1911 ngqsize++; 1912 splx(s); 1913 1914 /* Schedule software interrupt to handle it later */ 1915 schednetisr(NETISR_NETGRAPH); 1916 return (0); 1917 } 1918 1919 /* 1920 * Running at a raised (but we don't know which) processor priority level, 1921 * put the msg onto a queue to be picked up by another PPL (probably splnet) 1922 */ 1923 int 1924 ng_queue_msg(node_p here, struct ng_mesg *msg, const char *address) 1925 { 1926 register struct ng_queue_entry *q; 1927 int s; 1928 node_p dest = NULL; 1929 char *retaddr = NULL; 1930 int error; 1931 hook_p lasthook = NULL; 1932 1933 /* Find the target node. */ 1934 error = ng_path2node(here, address, &dest, &retaddr, &lasthook); 1935 if (error) { 1936 FREE(msg, M_NETGRAPH); 1937 return (error); 1938 } 1939 if ((q = ng_getqblk()) == NULL) { 1940 FREE(msg, M_NETGRAPH); 1941 if (retaddr) 1942 FREE(retaddr, M_NETGRAPH); 1943 return (ENOBUFS); 1944 } 1945 1946 /* Fill out the contents */ 1947 q->flags = NGQF_MESG; 1948 q->next = NULL; 1949 q->body.msg.msg_node = dest; 1950 q->body.msg.msg_msg = msg; 1951 q->body.msg.msg_retaddr = retaddr; 1952 q->body.msg.msg_lasthook = lasthook; 1953 dest->refs++; /* don't let it go away while on the queue */ 1954 if (lasthook) 1955 lasthook->refs++; /* same for the hook */ 1956 1957 /* Put it on the queue */ 1958 s = splhigh(); 1959 if (ngqbase) { 1960 ngqlast->next = q; 1961 } else { 1962 ngqbase = q; 1963 } 1964 ngqlast = q; 1965 ngqsize++; 1966 splx(s); 1967 1968 /* Schedule software interrupt to handle it later */ 1969 schednetisr(NETISR_NETGRAPH); 1970 return (0); 1971 } 1972 1973 /* 1974 * Pick an item off the queue, process it, and dispose of the queue entry. 1975 * Should be running at splnet. 1976 */ 1977 static void 1978 ngintr(void) 1979 { 1980 hook_p hook; 1981 struct ng_queue_entry *ngq; 1982 struct mbuf *m; 1983 meta_p meta; 1984 void *retaddr; 1985 struct ng_mesg *msg; 1986 node_p node; 1987 int error = 0; 1988 int s; 1989 1990 while (1) { 1991 s = splhigh(); 1992 if ((ngq = ngqbase)) { 1993 ngqbase = ngq->next; 1994 ngqsize--; 1995 } 1996 splx(s); 1997 if (ngq == NULL) 1998 return; 1999 switch (ngq->flags) { 2000 case NGQF_DATA: 2001 hook = ngq->body.data.da_hook; 2002 m = ngq->body.data.da_m; 2003 meta = ngq->body.data.da_meta; 2004 RETURN_QBLK(ngq); 2005 NG_SEND_DATAQ(error, hook, m, meta); 2006 ng_unref_hook(hook); 2007 break; 2008 case NGQF_MESG: 2009 node = ngq->body.msg.msg_node; 2010 msg = ngq->body.msg.msg_msg; 2011 retaddr = ngq->body.msg.msg_retaddr; 2012 hook = ngq->body.msg.msg_lasthook; 2013 RETURN_QBLK(ngq); 2014 if (hook) { 2015 if ((hook->refs == 1) 2016 || (hook->flags & HK_INVALID) != 0) { 2017 /* If the hook only has one ref left 2018 then we can't use it */ 2019 ng_unref_hook(hook); 2020 hook = NULL; 2021 } else { 2022 ng_unref_hook(hook); 2023 } 2024 } 2025 /* similarly, if the node is a zombie.. */ 2026 if (node->flags & NG_INVALID) { 2027 FREE(msg, M_NETGRAPH); 2028 } else { 2029 CALL_MSG_HANDLER(error, node, msg, 2030 retaddr, NULL, hook); 2031 } 2032 ng_unref(node); 2033 if (retaddr) 2034 FREE(retaddr, M_NETGRAPH); 2035 break; 2036 default: 2037 RETURN_QBLK(ngq); 2038 } 2039 } 2040 } 2041 2042 2043