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@freebsd.org> 38 * Archie Cobbs <archie@freebsd.org> 39 * 40 * $FreeBSD: src/sys/netgraph/ng_base.c,v 1.11.2.17 2002/07/02 23:44:02 archie Exp $ 41 * $DragonFly: src/sys/netgraph/netgraph/ng_base.c,v 1.6 2003/08/07 21:54:32 dillon Exp $ 42 * $Whistle: ng_base.c,v 1.39 1999/01/28 23:54:53 julian Exp $ 43 */ 44 45 /* 46 * This file implements the base netgraph code. 47 */ 48 49 #include <sys/param.h> 50 #include <sys/systm.h> 51 #include <sys/errno.h> 52 #include <sys/kernel.h> 53 #include <sys/malloc.h> 54 #include <sys/syslog.h> 55 #include <sys/linker.h> 56 #include <sys/queue.h> 57 #include <sys/mbuf.h> 58 #include <sys/ctype.h> 59 #include <sys/sysctl.h> 60 #include <machine/limits.h> 61 62 #include <net/netisr.h> 63 64 #include <netgraph/ng_message.h> 65 #include <netgraph/netgraph.h> 66 #include <netgraph/ng_parse.h> 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 static ng_ID_t ng_decodeidname(const char *name); 86 static int ngb_mod_event(module_t mod, int event, void *data); 87 static void ngintr(void); 88 89 /* Our own netgraph malloc type */ 90 MALLOC_DEFINE(M_NETGRAPH, "netgraph", "netgraph structures and ctrl messages"); 91 92 /* Set this to Debugger("X") to catch all errors as they occur */ 93 #ifndef TRAP_ERROR 94 #define TRAP_ERROR 95 #endif 96 97 static ng_ID_t nextID = 1; 98 99 #ifdef INVARIANTS 100 #define CHECK_DATA_MBUF(m) do { \ 101 struct mbuf *n; \ 102 int total; \ 103 \ 104 if (((m)->m_flags & M_PKTHDR) == 0) \ 105 panic("%s: !PKTHDR", __FUNCTION__); \ 106 for (total = 0, n = (m); n != NULL; n = n->m_next) \ 107 total += n->m_len; \ 108 if ((m)->m_pkthdr.len != total) { \ 109 panic("%s: %d != %d", \ 110 __FUNCTION__, (m)->m_pkthdr.len, total); \ 111 } \ 112 } while (0) 113 #else 114 #define CHECK_DATA_MBUF(m) 115 #endif 116 117 118 /************************************************************************ 119 Parse type definitions for generic messages 120 ************************************************************************/ 121 122 /* Handy structure parse type defining macro */ 123 #define DEFINE_PARSE_STRUCT_TYPE(lo, up, args) \ 124 static const struct ng_parse_struct_field \ 125 ng_ ## lo ## _type_fields[] = NG_GENERIC_ ## up ## _INFO args; \ 126 static const struct ng_parse_type ng_generic_ ## lo ## _type = { \ 127 &ng_parse_struct_type, \ 128 &ng_ ## lo ## _type_fields \ 129 } 130 131 DEFINE_PARSE_STRUCT_TYPE(mkpeer, MKPEER, ()); 132 DEFINE_PARSE_STRUCT_TYPE(connect, CONNECT, ()); 133 DEFINE_PARSE_STRUCT_TYPE(name, NAME, ()); 134 DEFINE_PARSE_STRUCT_TYPE(rmhook, RMHOOK, ()); 135 DEFINE_PARSE_STRUCT_TYPE(nodeinfo, NODEINFO, ()); 136 DEFINE_PARSE_STRUCT_TYPE(typeinfo, TYPEINFO, ()); 137 DEFINE_PARSE_STRUCT_TYPE(linkinfo, LINKINFO, (&ng_generic_nodeinfo_type)); 138 139 /* Get length of an array when the length is stored as a 32 bit 140 value immediately preceeding the array -- as with struct namelist 141 and struct typelist. */ 142 static int 143 ng_generic_list_getLength(const struct ng_parse_type *type, 144 const u_char *start, const u_char *buf) 145 { 146 return *((const u_int32_t *)(buf - 4)); 147 } 148 149 /* Get length of the array of struct linkinfo inside a struct hooklist */ 150 static int 151 ng_generic_linkinfo_getLength(const struct ng_parse_type *type, 152 const u_char *start, const u_char *buf) 153 { 154 const struct hooklist *hl = (const struct hooklist *)start; 155 156 return hl->nodeinfo.hooks; 157 } 158 159 /* Array type for a variable length array of struct namelist */ 160 static const struct ng_parse_array_info ng_nodeinfoarray_type_info = { 161 &ng_generic_nodeinfo_type, 162 &ng_generic_list_getLength 163 }; 164 static const struct ng_parse_type ng_generic_nodeinfoarray_type = { 165 &ng_parse_array_type, 166 &ng_nodeinfoarray_type_info 167 }; 168 169 /* Array type for a variable length array of struct typelist */ 170 static const struct ng_parse_array_info ng_typeinfoarray_type_info = { 171 &ng_generic_typeinfo_type, 172 &ng_generic_list_getLength 173 }; 174 static const struct ng_parse_type ng_generic_typeinfoarray_type = { 175 &ng_parse_array_type, 176 &ng_typeinfoarray_type_info 177 }; 178 179 /* Array type for array of struct linkinfo in struct hooklist */ 180 static const struct ng_parse_array_info ng_generic_linkinfo_array_type_info = { 181 &ng_generic_linkinfo_type, 182 &ng_generic_linkinfo_getLength 183 }; 184 static const struct ng_parse_type ng_generic_linkinfo_array_type = { 185 &ng_parse_array_type, 186 &ng_generic_linkinfo_array_type_info 187 }; 188 189 DEFINE_PARSE_STRUCT_TYPE(typelist, TYPELIST, (&ng_generic_nodeinfoarray_type)); 190 DEFINE_PARSE_STRUCT_TYPE(hooklist, HOOKLIST, 191 (&ng_generic_nodeinfo_type, &ng_generic_linkinfo_array_type)); 192 DEFINE_PARSE_STRUCT_TYPE(listnodes, LISTNODES, 193 (&ng_generic_nodeinfoarray_type)); 194 195 /* List of commands and how to convert arguments to/from ASCII */ 196 static const struct ng_cmdlist ng_generic_cmds[] = { 197 { 198 NGM_GENERIC_COOKIE, 199 NGM_SHUTDOWN, 200 "shutdown", 201 NULL, 202 NULL 203 }, 204 { 205 NGM_GENERIC_COOKIE, 206 NGM_MKPEER, 207 "mkpeer", 208 &ng_generic_mkpeer_type, 209 NULL 210 }, 211 { 212 NGM_GENERIC_COOKIE, 213 NGM_CONNECT, 214 "connect", 215 &ng_generic_connect_type, 216 NULL 217 }, 218 { 219 NGM_GENERIC_COOKIE, 220 NGM_NAME, 221 "name", 222 &ng_generic_name_type, 223 NULL 224 }, 225 { 226 NGM_GENERIC_COOKIE, 227 NGM_RMHOOK, 228 "rmhook", 229 &ng_generic_rmhook_type, 230 NULL 231 }, 232 { 233 NGM_GENERIC_COOKIE, 234 NGM_NODEINFO, 235 "nodeinfo", 236 NULL, 237 &ng_generic_nodeinfo_type 238 }, 239 { 240 NGM_GENERIC_COOKIE, 241 NGM_LISTHOOKS, 242 "listhooks", 243 NULL, 244 &ng_generic_hooklist_type 245 }, 246 { 247 NGM_GENERIC_COOKIE, 248 NGM_LISTNAMES, 249 "listnames", 250 NULL, 251 &ng_generic_listnodes_type /* same as NGM_LISTNODES */ 252 }, 253 { 254 NGM_GENERIC_COOKIE, 255 NGM_LISTNODES, 256 "listnodes", 257 NULL, 258 &ng_generic_listnodes_type 259 }, 260 { 261 NGM_GENERIC_COOKIE, 262 NGM_LISTTYPES, 263 "listtypes", 264 NULL, 265 &ng_generic_typeinfo_type 266 }, 267 { 268 NGM_GENERIC_COOKIE, 269 NGM_TEXT_CONFIG, 270 "textconfig", 271 NULL, 272 &ng_parse_string_type 273 }, 274 { 275 NGM_GENERIC_COOKIE, 276 NGM_TEXT_STATUS, 277 "textstatus", 278 NULL, 279 &ng_parse_string_type 280 }, 281 { 282 NGM_GENERIC_COOKIE, 283 NGM_ASCII2BINARY, 284 "ascii2binary", 285 &ng_parse_ng_mesg_type, 286 &ng_parse_ng_mesg_type 287 }, 288 { 289 NGM_GENERIC_COOKIE, 290 NGM_BINARY2ASCII, 291 "binary2ascii", 292 &ng_parse_ng_mesg_type, 293 &ng_parse_ng_mesg_type 294 }, 295 { 0 } 296 }; 297 298 /************************************************************************ 299 Node routines 300 ************************************************************************/ 301 302 /* 303 * Instantiate a node of the requested type 304 */ 305 int 306 ng_make_node(const char *typename, node_p *nodepp) 307 { 308 struct ng_type *type; 309 310 /* Check that the type makes sense */ 311 if (typename == NULL) { 312 TRAP_ERROR; 313 return (EINVAL); 314 } 315 316 /* Locate the node type */ 317 if ((type = ng_findtype(typename)) == NULL) { 318 char *path, filename[NG_TYPELEN + 4]; 319 linker_file_t lf; 320 int error; 321 322 /* Not found, try to load it as a loadable module */ 323 snprintf(filename, sizeof(filename), "ng_%s.ko", typename); 324 if ((path = linker_search_path(filename)) == NULL) 325 return (ENXIO); 326 error = linker_load_file(path, &lf); 327 FREE(path, M_LINKER); 328 if (error != 0) 329 return (error); 330 lf->userrefs++; /* pretend loaded by the syscall */ 331 332 /* Try again, as now the type should have linked itself in */ 333 if ((type = ng_findtype(typename)) == NULL) 334 return (ENXIO); 335 } 336 337 /* Call the constructor */ 338 if (type->constructor != NULL) 339 return ((*type->constructor)(nodepp)); 340 else 341 return (ng_make_node_common(type, nodepp)); 342 } 343 344 /* 345 * Generic node creation. Called by node constructors. 346 * The returned node has a reference count of 1. 347 */ 348 int 349 ng_make_node_common(struct ng_type *type, node_p *nodepp) 350 { 351 node_p node; 352 353 /* Require the node type to have been already installed */ 354 if (ng_findtype(type->name) == NULL) { 355 TRAP_ERROR; 356 return (EINVAL); 357 } 358 359 /* Make a node and try attach it to the type */ 360 MALLOC(node, node_p, sizeof(*node), M_NETGRAPH, M_NOWAIT); 361 if (node == NULL) { 362 TRAP_ERROR; 363 return (ENOMEM); 364 } 365 bzero(node, sizeof(*node)); 366 node->type = type; 367 node->refs++; /* note reference */ 368 type->refs++; 369 370 /* Link us into the node linked list */ 371 LIST_INSERT_HEAD(&nodelist, node, nodes); 372 373 /* Initialize hook list for new node */ 374 LIST_INIT(&node->hooks); 375 376 /* get an ID and put us in the hash chain */ 377 node->ID = nextID++; /* 137 per second for 1 year before wrap */ 378 LIST_INSERT_HEAD(&ID_hash[node->ID % ID_HASH_SIZE], node, idnodes); 379 380 /* Done */ 381 *nodepp = node; 382 return (0); 383 } 384 385 /* 386 * Forceably start the shutdown process on a node. Either call 387 * it's shutdown method, or do the default shutdown if there is 388 * no type-specific method. 389 * 390 * Persistent nodes must have a type-specific method which 391 * resets the NG_INVALID flag. 392 */ 393 void 394 ng_rmnode(node_p node) 395 { 396 /* Check if it's already shutting down */ 397 if ((node->flags & NG_INVALID) != 0) 398 return; 399 400 /* Add an extra reference so it doesn't go away during this */ 401 node->refs++; 402 403 /* Mark it invalid so any newcomers know not to try use it */ 404 node->flags |= NG_INVALID; 405 406 /* Ask the type if it has anything to do in this case */ 407 if (node->type && node->type->shutdown) 408 (*node->type->shutdown)(node); 409 else { /* do the default thing */ 410 ng_unname(node); 411 ng_cutlinks(node); 412 ng_unref(node); 413 } 414 415 /* Remove extra reference, possibly the last */ 416 ng_unref(node); 417 } 418 419 /* 420 * Called by the destructor to remove any STANDARD external references 421 */ 422 void 423 ng_cutlinks(node_p node) 424 { 425 hook_p hook; 426 427 /* Make sure that this is set to stop infinite loops */ 428 node->flags |= NG_INVALID; 429 430 /* If we have sleepers, wake them up; they'll see NG_INVALID */ 431 if (node->sleepers) 432 wakeup(node); 433 434 /* Notify all remaining connected nodes to disconnect */ 435 while ((hook = LIST_FIRST(&node->hooks)) != NULL) 436 ng_destroy_hook(hook); 437 } 438 439 /* 440 * Remove a reference to the node, possibly the last 441 */ 442 void 443 ng_unref(node_p node) 444 { 445 int s; 446 447 s = splhigh(); 448 if (--node->refs <= 0) { 449 node->type->refs--; 450 LIST_REMOVE(node, nodes); 451 LIST_REMOVE(node, idnodes); 452 FREE(node, M_NETGRAPH); 453 } 454 splx(s); 455 } 456 457 /* 458 * Wait for a node to come ready. Returns a node with a reference count; 459 * don't forget to drop it when we are done with it using ng_release_node(). 460 */ 461 int 462 ng_wait_node(node_p node, char *msg) 463 { 464 int s, error = 0; 465 466 if (msg == NULL) 467 msg = "netgraph"; 468 s = splnet(); 469 node->sleepers++; 470 node->refs++; /* the sleeping process counts as a reference */ 471 while ((node->flags & (NG_BUSY | NG_INVALID)) == NG_BUSY) 472 error = tsleep(node, PCATCH, msg, 0); 473 node->sleepers--; 474 if (node->flags & NG_INVALID) { 475 TRAP_ERROR; 476 error = ENXIO; 477 } else { 478 KASSERT(node->refs > 1, 479 ("%s: refs=%d", __FUNCTION__, node->refs)); 480 node->flags |= NG_BUSY; 481 } 482 splx(s); 483 484 /* Release the reference we had on it */ 485 if (error != 0) 486 ng_unref(node); 487 return error; 488 } 489 490 /* 491 * Release a node acquired via ng_wait_node() 492 */ 493 void 494 ng_release_node(node_p node) 495 { 496 /* Declare that we don't want it */ 497 node->flags &= ~NG_BUSY; 498 499 /* If we have sleepers, then wake them up */ 500 if (node->sleepers) 501 wakeup(node); 502 503 /* We also have a reference.. drop it too */ 504 ng_unref(node); 505 } 506 507 /************************************************************************ 508 Node ID handling 509 ************************************************************************/ 510 static node_p 511 ng_ID2node(ng_ID_t ID) 512 { 513 node_p np; 514 LIST_FOREACH(np, &ID_hash[ID % ID_HASH_SIZE], idnodes) { 515 if ((np->flags & NG_INVALID) == 0 && np->ID == ID) 516 break; 517 } 518 return(np); 519 } 520 521 ng_ID_t 522 ng_node2ID(node_p node) 523 { 524 return (node->ID); 525 } 526 527 /************************************************************************ 528 Node name handling 529 ************************************************************************/ 530 531 /* 532 * Assign a node a name. Once assigned, the name cannot be changed. 533 */ 534 int 535 ng_name_node(node_p node, const char *name) 536 { 537 int i; 538 539 /* Check the name is valid */ 540 for (i = 0; i < NG_NODELEN + 1; i++) { 541 if (name[i] == '\0' || name[i] == '.' || name[i] == ':') 542 break; 543 } 544 if (i == 0 || name[i] != '\0') { 545 TRAP_ERROR; 546 return (EINVAL); 547 } 548 if (ng_decodeidname(name) != 0) { /* valid IDs not allowed here */ 549 TRAP_ERROR; 550 return (EINVAL); 551 } 552 553 /* Check the node isn't already named */ 554 if (node->name != NULL) { 555 TRAP_ERROR; 556 return (EISCONN); 557 } 558 559 /* Check the name isn't already being used */ 560 if (ng_findname(node, name) != NULL) { 561 TRAP_ERROR; 562 return (EADDRINUSE); 563 } 564 565 /* Allocate space and copy it */ 566 MALLOC(node->name, char *, strlen(name) + 1, M_NETGRAPH, M_NOWAIT); 567 if (node->name == NULL) { 568 TRAP_ERROR; 569 return (ENOMEM); 570 } 571 strcpy(node->name, name); 572 573 /* The name counts as a reference */ 574 node->refs++; 575 return (0); 576 } 577 578 /* 579 * Find a node by absolute name. The name should NOT end with ':' 580 * The name "." means "this node" and "[xxx]" means "the node 581 * with ID (ie, at address) xxx". 582 * 583 * Returns the node if found, else NULL. 584 */ 585 node_p 586 ng_findname(node_p this, const char *name) 587 { 588 node_p node; 589 ng_ID_t temp; 590 591 /* "." means "this node" */ 592 if (strcmp(name, ".") == 0) 593 return(this); 594 595 /* Check for name-by-ID */ 596 if ((temp = ng_decodeidname(name)) != 0) { 597 return (ng_ID2node(temp)); 598 } 599 600 /* Find node by name */ 601 LIST_FOREACH(node, &nodelist, nodes) { 602 if ((node->name != NULL) 603 && (strcmp(node->name, name) == 0) 604 && ((node->flags & NG_INVALID) == 0)) 605 break; 606 } 607 return (node); 608 } 609 610 /* 611 * Decode a ID name, eg. "[f03034de]". Returns 0 if the 612 * string is not valid, otherwise returns the value. 613 */ 614 static ng_ID_t 615 ng_decodeidname(const char *name) 616 { 617 const int len = strlen(name); 618 char *eptr; 619 u_long val; 620 621 /* Check for proper length, brackets, no leading junk */ 622 if (len < 3 || name[0] != '[' || name[len - 1] != ']' 623 || !isxdigit(name[1])) 624 return (0); 625 626 /* Decode number */ 627 val = strtoul(name + 1, &eptr, 16); 628 if (eptr - name != len - 1 || val == ULONG_MAX || val == 0) 629 return ((ng_ID_t)0); 630 return (ng_ID_t)val; 631 } 632 633 /* 634 * Remove a name from a node. This should only be called 635 * when shutting down and removing the node. 636 */ 637 void 638 ng_unname(node_p node) 639 { 640 if (node->name) { 641 FREE(node->name, M_NETGRAPH); 642 node->name = NULL; 643 ng_unref(node); 644 } 645 } 646 647 /************************************************************************ 648 Hook routines 649 650 Names are not optional. Hooks are always connected, except for a 651 brief moment within these routines. 652 653 ************************************************************************/ 654 655 /* 656 * Remove a hook reference 657 */ 658 void 659 ng_unref_hook(hook_p hook) 660 { 661 int s; 662 663 s = splhigh(); 664 if (--hook->refs == 0) 665 FREE(hook, M_NETGRAPH); 666 splx(s); 667 } 668 669 /* 670 * Add an unconnected hook to a node. Only used internally. 671 */ 672 static int 673 ng_add_hook(node_p node, const char *name, hook_p *hookp) 674 { 675 hook_p hook; 676 int error = 0; 677 678 /* Check that the given name is good */ 679 if (name == NULL) { 680 TRAP_ERROR; 681 return (EINVAL); 682 } 683 if (ng_findhook(node, name) != NULL) { 684 TRAP_ERROR; 685 return (EEXIST); 686 } 687 688 /* Allocate the hook and link it up */ 689 MALLOC(hook, hook_p, sizeof(*hook), M_NETGRAPH, M_NOWAIT); 690 if (hook == NULL) { 691 TRAP_ERROR; 692 return (ENOMEM); 693 } 694 bzero(hook, sizeof(*hook)); 695 hook->refs = 1; 696 hook->flags = HK_INVALID; 697 hook->node = node; 698 node->refs++; /* each hook counts as a reference */ 699 700 /* Check if the node type code has something to say about it */ 701 if (node->type->newhook != NULL) 702 if ((error = (*node->type->newhook)(node, hook, name)) != 0) 703 goto fail; 704 705 /* 706 * The 'type' agrees so far, so go ahead and link it in. 707 * We'll ask again later when we actually connect the hooks. 708 */ 709 LIST_INSERT_HEAD(&node->hooks, hook, hooks); 710 node->numhooks++; 711 712 /* Set hook name */ 713 MALLOC(hook->name, char *, strlen(name) + 1, M_NETGRAPH, M_NOWAIT); 714 if (hook->name == NULL) { 715 error = ENOMEM; 716 LIST_REMOVE(hook, hooks); 717 node->numhooks--; 718 fail: 719 hook->node = NULL; 720 ng_unref(node); 721 ng_unref_hook(hook); /* this frees the hook */ 722 return (error); 723 } 724 strcpy(hook->name, name); 725 if (hookp) 726 *hookp = hook; 727 return (error); 728 } 729 730 /* 731 * Connect a pair of hooks. Only used internally. 732 */ 733 static int 734 ng_connect(hook_p hook1, hook_p hook2) 735 { 736 int error; 737 738 hook1->peer = hook2; 739 hook2->peer = hook1; 740 741 /* Give each node the opportunity to veto the impending connection */ 742 if (hook1->node->type->connect) { 743 if ((error = (*hook1->node->type->connect) (hook1))) { 744 ng_destroy_hook(hook1); /* also zaps hook2 */ 745 return (error); 746 } 747 } 748 if (hook2->node->type->connect) { 749 if ((error = (*hook2->node->type->connect) (hook2))) { 750 ng_destroy_hook(hook2); /* also zaps hook1 */ 751 return (error); 752 } 753 } 754 hook1->flags &= ~HK_INVALID; 755 hook2->flags &= ~HK_INVALID; 756 return (0); 757 } 758 759 /* 760 * Find a hook 761 * 762 * Node types may supply their own optimized routines for finding 763 * hooks. If none is supplied, we just do a linear search. 764 */ 765 hook_p 766 ng_findhook(node_p node, const char *name) 767 { 768 hook_p hook; 769 770 if (node->type->findhook != NULL) 771 return (*node->type->findhook)(node, name); 772 LIST_FOREACH(hook, &node->hooks, hooks) { 773 if (hook->name != NULL 774 && strcmp(hook->name, name) == 0 775 && (hook->flags & HK_INVALID) == 0) 776 return (hook); 777 } 778 return (NULL); 779 } 780 781 /* 782 * Destroy a hook 783 * 784 * As hooks are always attached, this really destroys two hooks. 785 * The one given, and the one attached to it. Disconnect the hooks 786 * from each other first. 787 */ 788 void 789 ng_destroy_hook(hook_p hook) 790 { 791 hook_p peer = hook->peer; 792 793 hook->flags |= HK_INVALID; /* as soon as possible */ 794 if (peer) { 795 peer->flags |= HK_INVALID; /* as soon as possible */ 796 hook->peer = NULL; 797 peer->peer = NULL; 798 ng_disconnect_hook(peer); 799 } 800 ng_disconnect_hook(hook); 801 } 802 803 /* 804 * Notify the node of the hook's demise. This may result in more actions 805 * (e.g. shutdown) but we don't do that ourselves and don't know what 806 * happens there. If there is no appropriate handler, then just remove it 807 * (and decrement the reference count of it's node which in turn might 808 * make something happen). 809 */ 810 static void 811 ng_disconnect_hook(hook_p hook) 812 { 813 node_p node = hook->node; 814 815 /* 816 * Remove the hook from the node's list to avoid possible recursion 817 * in case the disconnection results in node shutdown. 818 */ 819 LIST_REMOVE(hook, hooks); 820 node->numhooks--; 821 if (node->type->disconnect) { 822 /* 823 * The type handler may elect to destroy the peer so don't 824 * trust its existance after this point. 825 */ 826 (*node->type->disconnect) (hook); 827 } 828 ng_unref(node); /* might be the last reference */ 829 if (hook->name) 830 FREE(hook->name, M_NETGRAPH); 831 hook->node = NULL; /* may still be referenced elsewhere */ 832 ng_unref_hook(hook); 833 } 834 835 /* 836 * Take two hooks on a node and merge the connection so that the given node 837 * is effectively bypassed. 838 */ 839 int 840 ng_bypass(hook_p hook1, hook_p hook2) 841 { 842 if (hook1->node != hook2->node) 843 return (EINVAL); 844 hook1->peer->peer = hook2->peer; 845 hook2->peer->peer = hook1->peer; 846 847 /* XXX If we ever cache methods on hooks update them as well */ 848 hook1->peer = NULL; 849 hook2->peer = NULL; 850 ng_destroy_hook(hook1); 851 ng_destroy_hook(hook2); 852 return (0); 853 } 854 855 /* 856 * Install a new netgraph type 857 */ 858 int 859 ng_newtype(struct ng_type *tp) 860 { 861 const size_t namelen = strlen(tp->name); 862 863 /* Check version and type name fields */ 864 if (tp->version != NG_VERSION || namelen == 0 || namelen > NG_TYPELEN) { 865 TRAP_ERROR; 866 return (EINVAL); 867 } 868 869 /* Check for name collision */ 870 if (ng_findtype(tp->name) != NULL) { 871 TRAP_ERROR; 872 return (EEXIST); 873 } 874 875 /* Link in new type */ 876 LIST_INSERT_HEAD(&typelist, tp, types); 877 tp->refs = 1; /* first ref is linked list */ 878 return (0); 879 } 880 881 /* 882 * Look for a type of the name given 883 */ 884 struct ng_type * 885 ng_findtype(const char *typename) 886 { 887 struct ng_type *type; 888 889 LIST_FOREACH(type, &typelist, types) { 890 if (strcmp(type->name, typename) == 0) 891 break; 892 } 893 return (type); 894 } 895 896 897 /************************************************************************ 898 Composite routines 899 ************************************************************************/ 900 901 /* 902 * Make a peer and connect. The order is arranged to minimise 903 * the work needed to back out in case of error. 904 */ 905 int 906 ng_mkpeer(node_p node, const char *name, const char *name2, char *type) 907 { 908 node_p node2; 909 hook_p hook; 910 hook_p hook2; 911 int error; 912 913 if ((error = ng_add_hook(node, name, &hook))) 914 return (error); 915 if ((error = ng_make_node(type, &node2))) { 916 ng_destroy_hook(hook); 917 return (error); 918 } 919 if ((error = ng_add_hook(node2, name2, &hook2))) { 920 ng_rmnode(node2); 921 ng_destroy_hook(hook); 922 return (error); 923 } 924 925 /* 926 * Actually link the two hooks together.. on failure they are 927 * destroyed so we don't have to do that here. 928 */ 929 if ((error = ng_connect(hook, hook2))) 930 ng_rmnode(node2); 931 return (error); 932 } 933 934 /* 935 * Connect two nodes using the specified hooks 936 */ 937 int 938 ng_con_nodes(node_p node, const char *name, node_p node2, const char *name2) 939 { 940 int error; 941 hook_p hook; 942 hook_p hook2; 943 944 if ((error = ng_add_hook(node, name, &hook))) 945 return (error); 946 if ((error = ng_add_hook(node2, name2, &hook2))) { 947 ng_destroy_hook(hook); 948 return (error); 949 } 950 return (ng_connect(hook, hook2)); 951 } 952 953 /* 954 * Parse and verify a string of the form: <NODE:><PATH> 955 * 956 * Such a string can refer to a specific node or a specific hook 957 * on a specific node, depending on how you look at it. In the 958 * latter case, the PATH component must not end in a dot. 959 * 960 * Both <NODE:> and <PATH> are optional. The <PATH> is a string 961 * of hook names separated by dots. This breaks out the original 962 * string, setting *nodep to "NODE" (or NULL if none) and *pathp 963 * to "PATH" (or NULL if degenerate). Also, *hookp will point to 964 * the final hook component of <PATH>, if any, otherwise NULL. 965 * 966 * This returns -1 if the path is malformed. The char ** are optional. 967 */ 968 969 int 970 ng_path_parse(char *addr, char **nodep, char **pathp, char **hookp) 971 { 972 char *node, *path, *hook; 973 int k; 974 975 /* 976 * Extract absolute NODE, if any 977 */ 978 for (path = addr; *path && *path != ':'; path++); 979 if (*path) { 980 node = addr; /* Here's the NODE */ 981 *path++ = '\0'; /* Here's the PATH */ 982 983 /* Node name must not be empty */ 984 if (!*node) 985 return -1; 986 987 /* A name of "." is OK; otherwise '.' not allowed */ 988 if (strcmp(node, ".") != 0) { 989 for (k = 0; node[k]; k++) 990 if (node[k] == '.') 991 return -1; 992 } 993 } else { 994 node = NULL; /* No absolute NODE */ 995 path = addr; /* Here's the PATH */ 996 } 997 998 /* Snoop for illegal characters in PATH */ 999 for (k = 0; path[k]; k++) 1000 if (path[k] == ':') 1001 return -1; 1002 1003 /* Check for no repeated dots in PATH */ 1004 for (k = 0; path[k]; k++) 1005 if (path[k] == '.' && path[k + 1] == '.') 1006 return -1; 1007 1008 /* Remove extra (degenerate) dots from beginning or end of PATH */ 1009 if (path[0] == '.') 1010 path++; 1011 if (*path && path[strlen(path) - 1] == '.') 1012 path[strlen(path) - 1] = 0; 1013 1014 /* If PATH has a dot, then we're not talking about a hook */ 1015 if (*path) { 1016 for (hook = path, k = 0; path[k]; k++) 1017 if (path[k] == '.') { 1018 hook = NULL; 1019 break; 1020 } 1021 } else 1022 path = hook = NULL; 1023 1024 /* Done */ 1025 if (nodep) 1026 *nodep = node; 1027 if (pathp) 1028 *pathp = path; 1029 if (hookp) 1030 *hookp = hook; 1031 return (0); 1032 } 1033 1034 /* 1035 * Given a path, which may be absolute or relative, and a starting node, 1036 * return the destination node. Compute the "return address" if desired. 1037 */ 1038 int 1039 ng_path2node(node_p here, const char *address, node_p *destp, char **rtnp) 1040 { 1041 const node_p start = here; 1042 char fullpath[NG_PATHLEN + 1]; 1043 char *nodename, *path, pbuf[2]; 1044 node_p node; 1045 char *cp; 1046 1047 /* Initialize */ 1048 if (rtnp) 1049 *rtnp = NULL; 1050 if (destp == NULL) 1051 return EINVAL; 1052 *destp = NULL; 1053 1054 /* Make a writable copy of address for ng_path_parse() */ 1055 strncpy(fullpath, address, sizeof(fullpath) - 1); 1056 fullpath[sizeof(fullpath) - 1] = '\0'; 1057 1058 /* Parse out node and sequence of hooks */ 1059 if (ng_path_parse(fullpath, &nodename, &path, NULL) < 0) { 1060 TRAP_ERROR; 1061 return EINVAL; 1062 } 1063 if (path == NULL) { 1064 pbuf[0] = '.'; /* Needs to be writable */ 1065 pbuf[1] = '\0'; 1066 path = pbuf; 1067 } 1068 1069 /* For an absolute address, jump to the starting node */ 1070 if (nodename) { 1071 node = ng_findname(here, nodename); 1072 if (node == NULL) { 1073 TRAP_ERROR; 1074 return (ENOENT); 1075 } 1076 } else 1077 node = here; 1078 1079 /* Now follow the sequence of hooks */ 1080 for (cp = path; node != NULL && *cp != '\0'; ) { 1081 hook_p hook; 1082 char *segment; 1083 1084 /* 1085 * Break out the next path segment. Replace the dot we just 1086 * found with a NUL; "cp" points to the next segment (or the 1087 * NUL at the end). 1088 */ 1089 for (segment = cp; *cp != '\0'; cp++) { 1090 if (*cp == '.') { 1091 *cp++ = '\0'; 1092 break; 1093 } 1094 } 1095 1096 /* Empty segment */ 1097 if (*segment == '\0') 1098 continue; 1099 1100 /* We have a segment, so look for a hook by that name */ 1101 hook = ng_findhook(node, segment); 1102 1103 /* Can't get there from here... */ 1104 if (hook == NULL 1105 || hook->peer == NULL 1106 || (hook->flags & HK_INVALID) != 0) { 1107 TRAP_ERROR; 1108 return (ENOENT); 1109 } 1110 1111 /* Hop on over to the next node */ 1112 node = hook->peer->node; 1113 } 1114 1115 /* If node somehow missing, fail here (probably this is not needed) */ 1116 if (node == NULL) { 1117 TRAP_ERROR; 1118 return (ENXIO); 1119 } 1120 1121 /* Now compute return address, i.e., the path to the sender */ 1122 if (rtnp != NULL) { 1123 MALLOC(*rtnp, char *, NG_NODELEN + 2, M_NETGRAPH, M_NOWAIT); 1124 if (*rtnp == NULL) { 1125 TRAP_ERROR; 1126 return (ENOMEM); 1127 } 1128 if (start->name != NULL) 1129 sprintf(*rtnp, "%s:", start->name); 1130 else 1131 sprintf(*rtnp, "[%x]:", ng_node2ID(start)); 1132 } 1133 1134 /* Done */ 1135 *destp = node; 1136 return (0); 1137 } 1138 1139 /* 1140 * Call the appropriate message handler for the object. 1141 * It is up to the message handler to free the message. 1142 * If it's a generic message, handle it generically, otherwise 1143 * call the type's message handler (if it exists) 1144 * XXX (race). Remember that a queued message may reference a node 1145 * or hook that has just been invalidated. It will exist 1146 * as the queue code is holding a reference, but.. 1147 */ 1148 1149 #define CALL_MSG_HANDLER(error, node, msg, retaddr, resp) \ 1150 do { \ 1151 if((msg)->header.typecookie == NGM_GENERIC_COOKIE) { \ 1152 (error) = ng_generic_msg((node), (msg), \ 1153 (retaddr), (resp)); \ 1154 } else { \ 1155 if ((node)->type->rcvmsg != NULL) { \ 1156 (error) = (*(node)->type->rcvmsg)((node), \ 1157 (msg), (retaddr), (resp)); \ 1158 } else { \ 1159 TRAP_ERROR; \ 1160 FREE((msg), M_NETGRAPH); \ 1161 (error) = EINVAL; \ 1162 } \ 1163 } \ 1164 } while (0) 1165 1166 1167 /* 1168 * Send a control message to a node 1169 */ 1170 int 1171 ng_send_msg(node_p here, struct ng_mesg *msg, const char *address, 1172 struct ng_mesg **rptr) 1173 { 1174 node_p dest = NULL; 1175 char *retaddr = NULL; 1176 int error; 1177 1178 /* Find the target node */ 1179 error = ng_path2node(here, address, &dest, &retaddr); 1180 if (error) { 1181 FREE(msg, M_NETGRAPH); 1182 return error; 1183 } 1184 1185 /* Make sure the resp field is null before we start */ 1186 if (rptr != NULL) 1187 *rptr = NULL; 1188 1189 CALL_MSG_HANDLER(error, dest, msg, retaddr, rptr); 1190 1191 /* Make sure that if there is a response, it has the RESP bit set */ 1192 if ((error == 0) && rptr && *rptr) 1193 (*rptr)->header.flags |= NGF_RESP; 1194 1195 /* 1196 * If we had a return address it is up to us to free it. They should 1197 * have taken a copy if they needed to make a delayed response. 1198 */ 1199 if (retaddr) 1200 FREE(retaddr, M_NETGRAPH); 1201 return (error); 1202 } 1203 1204 /* 1205 * Implement the 'generic' control messages 1206 */ 1207 static int 1208 ng_generic_msg(node_p here, struct ng_mesg *msg, const char *retaddr, 1209 struct ng_mesg **resp) 1210 { 1211 int error = 0; 1212 1213 if (msg->header.typecookie != NGM_GENERIC_COOKIE) { 1214 TRAP_ERROR; 1215 FREE(msg, M_NETGRAPH); 1216 return (EINVAL); 1217 } 1218 switch (msg->header.cmd) { 1219 case NGM_SHUTDOWN: 1220 ng_rmnode(here); 1221 break; 1222 case NGM_MKPEER: 1223 { 1224 struct ngm_mkpeer *const mkp = (struct ngm_mkpeer *) msg->data; 1225 1226 if (msg->header.arglen != sizeof(*mkp)) { 1227 TRAP_ERROR; 1228 return (EINVAL); 1229 } 1230 mkp->type[sizeof(mkp->type) - 1] = '\0'; 1231 mkp->ourhook[sizeof(mkp->ourhook) - 1] = '\0'; 1232 mkp->peerhook[sizeof(mkp->peerhook) - 1] = '\0'; 1233 error = ng_mkpeer(here, mkp->ourhook, mkp->peerhook, mkp->type); 1234 break; 1235 } 1236 case NGM_CONNECT: 1237 { 1238 struct ngm_connect *const con = 1239 (struct ngm_connect *) msg->data; 1240 node_p node2; 1241 1242 if (msg->header.arglen != sizeof(*con)) { 1243 TRAP_ERROR; 1244 return (EINVAL); 1245 } 1246 con->path[sizeof(con->path) - 1] = '\0'; 1247 con->ourhook[sizeof(con->ourhook) - 1] = '\0'; 1248 con->peerhook[sizeof(con->peerhook) - 1] = '\0'; 1249 error = ng_path2node(here, con->path, &node2, NULL); 1250 if (error) 1251 break; 1252 error = ng_con_nodes(here, con->ourhook, node2, con->peerhook); 1253 break; 1254 } 1255 case NGM_NAME: 1256 { 1257 struct ngm_name *const nam = (struct ngm_name *) msg->data; 1258 1259 if (msg->header.arglen != sizeof(*nam)) { 1260 TRAP_ERROR; 1261 return (EINVAL); 1262 } 1263 nam->name[sizeof(nam->name) - 1] = '\0'; 1264 error = ng_name_node(here, nam->name); 1265 break; 1266 } 1267 case NGM_RMHOOK: 1268 { 1269 struct ngm_rmhook *const rmh = (struct ngm_rmhook *) msg->data; 1270 hook_p hook; 1271 1272 if (msg->header.arglen != sizeof(*rmh)) { 1273 TRAP_ERROR; 1274 return (EINVAL); 1275 } 1276 rmh->ourhook[sizeof(rmh->ourhook) - 1] = '\0'; 1277 if ((hook = ng_findhook(here, rmh->ourhook)) != NULL) 1278 ng_destroy_hook(hook); 1279 break; 1280 } 1281 case NGM_NODEINFO: 1282 { 1283 struct nodeinfo *ni; 1284 struct ng_mesg *rp; 1285 1286 /* Get response struct */ 1287 if (resp == NULL) { 1288 error = EINVAL; 1289 break; 1290 } 1291 NG_MKRESPONSE(rp, msg, sizeof(*ni), M_NOWAIT); 1292 if (rp == NULL) { 1293 error = ENOMEM; 1294 break; 1295 } 1296 1297 /* Fill in node info */ 1298 ni = (struct nodeinfo *) rp->data; 1299 if (here->name != NULL) 1300 strncpy(ni->name, here->name, NG_NODELEN); 1301 strncpy(ni->type, here->type->name, NG_TYPELEN); 1302 ni->id = ng_node2ID(here); 1303 ni->hooks = here->numhooks; 1304 *resp = rp; 1305 break; 1306 } 1307 case NGM_LISTHOOKS: 1308 { 1309 const int nhooks = here->numhooks; 1310 struct hooklist *hl; 1311 struct nodeinfo *ni; 1312 struct ng_mesg *rp; 1313 hook_p hook; 1314 1315 /* Get response struct */ 1316 if (resp == NULL) { 1317 error = EINVAL; 1318 break; 1319 } 1320 NG_MKRESPONSE(rp, msg, sizeof(*hl) 1321 + (nhooks * sizeof(struct linkinfo)), M_NOWAIT); 1322 if (rp == NULL) { 1323 error = ENOMEM; 1324 break; 1325 } 1326 hl = (struct hooklist *) rp->data; 1327 ni = &hl->nodeinfo; 1328 1329 /* Fill in node info */ 1330 if (here->name) 1331 strncpy(ni->name, here->name, NG_NODELEN); 1332 strncpy(ni->type, here->type->name, NG_TYPELEN); 1333 ni->id = ng_node2ID(here); 1334 1335 /* Cycle through the linked list of hooks */ 1336 ni->hooks = 0; 1337 LIST_FOREACH(hook, &here->hooks, hooks) { 1338 struct linkinfo *const link = &hl->link[ni->hooks]; 1339 1340 if (ni->hooks >= nhooks) { 1341 log(LOG_ERR, "%s: number of %s changed\n", 1342 __FUNCTION__, "hooks"); 1343 break; 1344 } 1345 if ((hook->flags & HK_INVALID) != 0) 1346 continue; 1347 strncpy(link->ourhook, hook->name, NG_HOOKLEN); 1348 strncpy(link->peerhook, hook->peer->name, NG_HOOKLEN); 1349 if (hook->peer->node->name != NULL) 1350 strncpy(link->nodeinfo.name, 1351 hook->peer->node->name, NG_NODELEN); 1352 strncpy(link->nodeinfo.type, 1353 hook->peer->node->type->name, NG_TYPELEN); 1354 link->nodeinfo.id = ng_node2ID(hook->peer->node); 1355 link->nodeinfo.hooks = hook->peer->node->numhooks; 1356 ni->hooks++; 1357 } 1358 *resp = rp; 1359 break; 1360 } 1361 1362 case NGM_LISTNAMES: 1363 case NGM_LISTNODES: 1364 { 1365 const int unnamed = (msg->header.cmd == NGM_LISTNODES); 1366 struct namelist *nl; 1367 struct ng_mesg *rp; 1368 node_p node; 1369 int num = 0; 1370 1371 if (resp == NULL) { 1372 error = EINVAL; 1373 break; 1374 } 1375 1376 /* Count number of nodes */ 1377 LIST_FOREACH(node, &nodelist, nodes) { 1378 if ((node->flags & NG_INVALID) == 0 1379 && (unnamed || node->name != NULL)) 1380 num++; 1381 } 1382 1383 /* Get response struct */ 1384 if (resp == NULL) { 1385 error = EINVAL; 1386 break; 1387 } 1388 NG_MKRESPONSE(rp, msg, sizeof(*nl) 1389 + (num * sizeof(struct nodeinfo)), M_NOWAIT); 1390 if (rp == NULL) { 1391 error = ENOMEM; 1392 break; 1393 } 1394 nl = (struct namelist *) rp->data; 1395 1396 /* Cycle through the linked list of nodes */ 1397 nl->numnames = 0; 1398 LIST_FOREACH(node, &nodelist, nodes) { 1399 struct nodeinfo *const np = &nl->nodeinfo[nl->numnames]; 1400 1401 if (nl->numnames >= num) { 1402 log(LOG_ERR, "%s: number of %s changed\n", 1403 __FUNCTION__, "nodes"); 1404 break; 1405 } 1406 if ((node->flags & NG_INVALID) != 0) 1407 continue; 1408 if (!unnamed && node->name == NULL) 1409 continue; 1410 if (node->name != NULL) 1411 strncpy(np->name, node->name, NG_NODELEN); 1412 strncpy(np->type, node->type->name, NG_TYPELEN); 1413 np->id = ng_node2ID(node); 1414 np->hooks = node->numhooks; 1415 nl->numnames++; 1416 } 1417 *resp = rp; 1418 break; 1419 } 1420 1421 case NGM_LISTTYPES: 1422 { 1423 struct typelist *tl; 1424 struct ng_mesg *rp; 1425 struct ng_type *type; 1426 int num = 0; 1427 1428 if (resp == NULL) { 1429 error = EINVAL; 1430 break; 1431 } 1432 1433 /* Count number of types */ 1434 LIST_FOREACH(type, &typelist, types) 1435 num++; 1436 1437 /* Get response struct */ 1438 if (resp == NULL) { 1439 error = EINVAL; 1440 break; 1441 } 1442 NG_MKRESPONSE(rp, msg, sizeof(*tl) 1443 + (num * sizeof(struct typeinfo)), M_NOWAIT); 1444 if (rp == NULL) { 1445 error = ENOMEM; 1446 break; 1447 } 1448 tl = (struct typelist *) rp->data; 1449 1450 /* Cycle through the linked list of types */ 1451 tl->numtypes = 0; 1452 LIST_FOREACH(type, &typelist, types) { 1453 struct typeinfo *const tp = &tl->typeinfo[tl->numtypes]; 1454 1455 if (tl->numtypes >= num) { 1456 log(LOG_ERR, "%s: number of %s changed\n", 1457 __FUNCTION__, "types"); 1458 break; 1459 } 1460 strncpy(tp->type_name, type->name, NG_TYPELEN); 1461 tp->numnodes = type->refs - 1; /* don't count list */ 1462 tl->numtypes++; 1463 } 1464 *resp = rp; 1465 break; 1466 } 1467 1468 case NGM_BINARY2ASCII: 1469 { 1470 int bufSize = 20 * 1024; /* XXX hard coded constant */ 1471 const struct ng_parse_type *argstype; 1472 const struct ng_cmdlist *c; 1473 struct ng_mesg *rp, *binary, *ascii; 1474 1475 /* Data area must contain a valid netgraph message */ 1476 binary = (struct ng_mesg *)msg->data; 1477 if (msg->header.arglen < sizeof(struct ng_mesg) 1478 || msg->header.arglen - sizeof(struct ng_mesg) 1479 < binary->header.arglen) { 1480 error = EINVAL; 1481 break; 1482 } 1483 1484 /* Get a response message with lots of room */ 1485 NG_MKRESPONSE(rp, msg, sizeof(*ascii) + bufSize, M_NOWAIT); 1486 if (rp == NULL) { 1487 error = ENOMEM; 1488 break; 1489 } 1490 ascii = (struct ng_mesg *)rp->data; 1491 1492 /* Copy binary message header to response message payload */ 1493 bcopy(binary, ascii, sizeof(*binary)); 1494 1495 /* Find command by matching typecookie and command number */ 1496 for (c = here->type->cmdlist; 1497 c != NULL && c->name != NULL; c++) { 1498 if (binary->header.typecookie == c->cookie 1499 && binary->header.cmd == c->cmd) 1500 break; 1501 } 1502 if (c == NULL || c->name == NULL) { 1503 for (c = ng_generic_cmds; c->name != NULL; c++) { 1504 if (binary->header.typecookie == c->cookie 1505 && binary->header.cmd == c->cmd) 1506 break; 1507 } 1508 if (c->name == NULL) { 1509 FREE(rp, M_NETGRAPH); 1510 error = ENOSYS; 1511 break; 1512 } 1513 } 1514 1515 /* Convert command name to ASCII */ 1516 snprintf(ascii->header.cmdstr, sizeof(ascii->header.cmdstr), 1517 "%s", c->name); 1518 1519 /* Convert command arguments to ASCII */ 1520 argstype = (binary->header.flags & NGF_RESP) ? 1521 c->respType : c->mesgType; 1522 if (argstype == NULL) 1523 *ascii->data = '\0'; 1524 else { 1525 if ((error = ng_unparse(argstype, 1526 (u_char *)binary->data, 1527 ascii->data, bufSize)) != 0) { 1528 FREE(rp, M_NETGRAPH); 1529 break; 1530 } 1531 } 1532 1533 /* Return the result as struct ng_mesg plus ASCII string */ 1534 bufSize = strlen(ascii->data) + 1; 1535 ascii->header.arglen = bufSize; 1536 rp->header.arglen = sizeof(*ascii) + bufSize; 1537 *resp = rp; 1538 break; 1539 } 1540 1541 case NGM_ASCII2BINARY: 1542 { 1543 int bufSize = 2000; /* XXX hard coded constant */ 1544 const struct ng_cmdlist *c; 1545 const struct ng_parse_type *argstype; 1546 struct ng_mesg *rp, *ascii, *binary; 1547 int off = 0; 1548 1549 /* Data area must contain at least a struct ng_mesg + '\0' */ 1550 ascii = (struct ng_mesg *)msg->data; 1551 if (msg->header.arglen < sizeof(*ascii) + 1 1552 || ascii->header.arglen < 1 1553 || msg->header.arglen 1554 < sizeof(*ascii) + ascii->header.arglen) { 1555 error = EINVAL; 1556 break; 1557 } 1558 ascii->data[ascii->header.arglen - 1] = '\0'; 1559 1560 /* Get a response message with lots of room */ 1561 NG_MKRESPONSE(rp, msg, sizeof(*binary) + bufSize, M_NOWAIT); 1562 if (rp == NULL) { 1563 error = ENOMEM; 1564 break; 1565 } 1566 binary = (struct ng_mesg *)rp->data; 1567 1568 /* Copy ASCII message header to response message payload */ 1569 bcopy(ascii, binary, sizeof(*ascii)); 1570 1571 /* Find command by matching ASCII command string */ 1572 for (c = here->type->cmdlist; 1573 c != NULL && c->name != NULL; c++) { 1574 if (strcmp(ascii->header.cmdstr, c->name) == 0) 1575 break; 1576 } 1577 if (c == NULL || c->name == NULL) { 1578 for (c = ng_generic_cmds; c->name != NULL; c++) { 1579 if (strcmp(ascii->header.cmdstr, c->name) == 0) 1580 break; 1581 } 1582 if (c->name == NULL) { 1583 FREE(rp, M_NETGRAPH); 1584 error = ENOSYS; 1585 break; 1586 } 1587 } 1588 1589 /* Convert command name to binary */ 1590 binary->header.cmd = c->cmd; 1591 binary->header.typecookie = c->cookie; 1592 1593 /* Convert command arguments to binary */ 1594 argstype = (binary->header.flags & NGF_RESP) ? 1595 c->respType : c->mesgType; 1596 if (argstype == NULL) 1597 bufSize = 0; 1598 else { 1599 if ((error = ng_parse(argstype, ascii->data, 1600 &off, (u_char *)binary->data, &bufSize)) != 0) { 1601 FREE(rp, M_NETGRAPH); 1602 break; 1603 } 1604 } 1605 1606 /* Return the result */ 1607 binary->header.arglen = bufSize; 1608 rp->header.arglen = sizeof(*binary) + bufSize; 1609 *resp = rp; 1610 break; 1611 } 1612 1613 case NGM_TEXT_CONFIG: 1614 case NGM_TEXT_STATUS: 1615 /* 1616 * This one is tricky as it passes the command down to the 1617 * actual node, even though it is a generic type command. 1618 * This means we must assume that the msg is already freed 1619 * when control passes back to us. 1620 */ 1621 if (resp == NULL) { 1622 error = EINVAL; 1623 break; 1624 } 1625 if (here->type->rcvmsg != NULL) 1626 return((*here->type->rcvmsg)(here, msg, retaddr, resp)); 1627 /* Fall through if rcvmsg not supported */ 1628 default: 1629 TRAP_ERROR; 1630 error = EINVAL; 1631 } 1632 FREE(msg, M_NETGRAPH); 1633 return (error); 1634 } 1635 1636 /* 1637 * Send a data packet to a node. If the recipient has no 1638 * 'receive data' method, then silently discard the packet. 1639 */ 1640 int 1641 ng_send_data(hook_p hook, struct mbuf *m, meta_p meta) 1642 { 1643 int (*rcvdata)(hook_p, struct mbuf *, meta_p); 1644 int error; 1645 1646 CHECK_DATA_MBUF(m); 1647 if (hook && (hook->flags & HK_INVALID) == 0) { 1648 rcvdata = hook->peer->node->type->rcvdata; 1649 if (rcvdata != NULL) 1650 error = (*rcvdata)(hook->peer, m, meta); 1651 else { 1652 error = 0; 1653 NG_FREE_DATA(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 * Send a queued data packet to a node. If the recipient has no 1665 * 'receive queued data' method, then try the 'receive data' method above. 1666 */ 1667 int 1668 ng_send_dataq(hook_p hook, struct mbuf *m, meta_p meta) 1669 { 1670 int (*rcvdataq)(hook_p, struct mbuf *, meta_p); 1671 int error; 1672 1673 CHECK_DATA_MBUF(m); 1674 if (hook && (hook->flags & HK_INVALID) == 0) { 1675 rcvdataq = hook->peer->node->type->rcvdataq; 1676 if (rcvdataq != NULL) 1677 error = (*rcvdataq)(hook->peer, m, meta); 1678 else { 1679 error = ng_send_data(hook, m, meta); 1680 } 1681 } else { 1682 TRAP_ERROR; 1683 error = ENOTCONN; 1684 NG_FREE_DATA(m, meta); 1685 } 1686 return (error); 1687 } 1688 1689 /* 1690 * Copy a 'meta'. 1691 * 1692 * Returns new meta, or NULL if original meta is NULL or ENOMEM. 1693 */ 1694 meta_p 1695 ng_copy_meta(meta_p meta) 1696 { 1697 meta_p meta2; 1698 1699 if (meta == NULL) 1700 return (NULL); 1701 MALLOC(meta2, meta_p, meta->used_len, M_NETGRAPH, M_NOWAIT); 1702 if (meta2 == NULL) 1703 return (NULL); 1704 meta2->allocated_len = meta->used_len; 1705 bcopy(meta, meta2, meta->used_len); 1706 return (meta2); 1707 } 1708 1709 /************************************************************************ 1710 Module routines 1711 ************************************************************************/ 1712 1713 /* 1714 * Handle the loading/unloading of a netgraph node type module 1715 */ 1716 int 1717 ng_mod_event(module_t mod, int event, void *data) 1718 { 1719 struct ng_type *const type = data; 1720 int s, error = 0; 1721 1722 switch (event) { 1723 case MOD_LOAD: 1724 1725 /* Register new netgraph node type */ 1726 s = splnet(); 1727 if ((error = ng_newtype(type)) != 0) { 1728 splx(s); 1729 break; 1730 } 1731 1732 /* Call type specific code */ 1733 if (type->mod_event != NULL) 1734 if ((error = (*type->mod_event)(mod, event, data))) { 1735 type->refs--; /* undo it */ 1736 LIST_REMOVE(type, types); 1737 } 1738 splx(s); 1739 break; 1740 1741 case MOD_UNLOAD: 1742 s = splnet(); 1743 if (type->refs > 1) { /* make sure no nodes exist! */ 1744 error = EBUSY; 1745 } else { 1746 if (type->refs == 0) { 1747 /* failed load, nothing to undo */ 1748 splx(s); 1749 break; 1750 } 1751 if (type->mod_event != NULL) { /* check with type */ 1752 error = (*type->mod_event)(mod, event, data); 1753 if (error != 0) { /* type refuses.. */ 1754 splx(s); 1755 break; 1756 } 1757 } 1758 LIST_REMOVE(type, types); 1759 } 1760 splx(s); 1761 break; 1762 1763 default: 1764 if (type->mod_event != NULL) 1765 error = (*type->mod_event)(mod, event, data); 1766 else 1767 error = 0; /* XXX ? */ 1768 break; 1769 } 1770 return (error); 1771 } 1772 1773 /* 1774 * Handle loading and unloading for this code. 1775 * The only thing we need to link into is the NETISR strucure. 1776 */ 1777 static int 1778 ngb_mod_event(module_t mod, int event, void *data) 1779 { 1780 int s, error = 0; 1781 1782 switch (event) { 1783 case MOD_LOAD: 1784 /* Register line discipline */ 1785 s = splimp(); 1786 error = register_netisr(NETISR_NETGRAPH, ngintr); 1787 splx(s); 1788 break; 1789 case MOD_UNLOAD: 1790 /* You cant unload it because an interface may be using it. */ 1791 error = EBUSY; 1792 break; 1793 default: 1794 error = EOPNOTSUPP; 1795 break; 1796 } 1797 return (error); 1798 } 1799 1800 static moduledata_t netgraph_mod = { 1801 "netgraph", 1802 ngb_mod_event, 1803 (NULL) 1804 }; 1805 DECLARE_MODULE(netgraph, netgraph_mod, SI_SUB_DRIVERS, SI_ORDER_MIDDLE); 1806 SYSCTL_NODE(_net, OID_AUTO, graph, CTLFLAG_RW, 0, "netgraph Family"); 1807 SYSCTL_INT(_net_graph, OID_AUTO, abi_version, CTLFLAG_RD, 0, NG_ABI_VERSION,""); 1808 SYSCTL_INT(_net_graph, OID_AUTO, msg_version, CTLFLAG_RD, 0, NG_VERSION, ""); 1809 1810 /************************************************************************ 1811 Queueing routines 1812 ************************************************************************/ 1813 1814 /* The structure for queueing across ISR switches */ 1815 struct ng_queue_entry { 1816 u_long flags; 1817 struct ng_queue_entry *next; 1818 union { 1819 struct { 1820 hook_p da_hook; /* target hook */ 1821 struct mbuf *da_m; 1822 meta_p da_meta; 1823 } data; 1824 struct { 1825 struct ng_mesg *msg_msg; 1826 node_p msg_node; 1827 void *msg_retaddr; 1828 } msg; 1829 } body; 1830 }; 1831 #define NGQF_DATA 0x01 /* the queue element is data */ 1832 #define NGQF_MESG 0x02 /* the queue element is a message */ 1833 1834 static struct ng_queue_entry *ngqbase; /* items to be unqueued */ 1835 static struct ng_queue_entry *ngqlast; /* last item queued */ 1836 static const int ngqroom = 256; /* max items to queue */ 1837 static int ngqsize; /* number of items in queue */ 1838 1839 static struct ng_queue_entry *ngqfree; /* free ones */ 1840 static const int ngqfreemax = 256;/* cache at most this many */ 1841 static int ngqfreesize; /* number of cached entries */ 1842 1843 /* 1844 * Get a queue entry 1845 */ 1846 static struct ng_queue_entry * 1847 ng_getqblk(void) 1848 { 1849 struct ng_queue_entry *q; 1850 int s; 1851 1852 /* Could be guarding against tty ints or whatever */ 1853 s = splhigh(); 1854 1855 /* Try get a cached queue block, or else allocate a new one */ 1856 if ((q = ngqfree) == NULL) { 1857 splx(s); 1858 if (ngqsize < ngqroom) { /* don't worry about races */ 1859 MALLOC(q, struct ng_queue_entry *, 1860 sizeof(*q), M_NETGRAPH, M_NOWAIT); 1861 } 1862 } else { 1863 ngqfree = q->next; 1864 ngqfreesize--; 1865 splx(s); 1866 } 1867 return (q); 1868 } 1869 1870 /* 1871 * Release a queue entry 1872 */ 1873 #define RETURN_QBLK(q) \ 1874 do { \ 1875 int s; \ 1876 if (ngqfreesize < ngqfreemax) { /* don't worry about races */ \ 1877 s = splhigh(); \ 1878 (q)->next = ngqfree; \ 1879 ngqfree = (q); \ 1880 ngqfreesize++; \ 1881 splx(s); \ 1882 } else { \ 1883 FREE((q), M_NETGRAPH); \ 1884 } \ 1885 } while (0) 1886 1887 /* 1888 * Running at a raised (but we don't know which) processor priority level, 1889 * put the data onto a queue to be picked up by another PPL (probably splnet) 1890 */ 1891 int 1892 ng_queue_data(hook_p hook, struct mbuf *m, meta_p meta) 1893 { 1894 struct ng_queue_entry *q; 1895 int s; 1896 1897 if (hook == NULL) { 1898 NG_FREE_DATA(m, meta); 1899 return (0); 1900 } 1901 if ((q = ng_getqblk()) == NULL) { 1902 NG_FREE_DATA(m, meta); 1903 return (ENOBUFS); 1904 } 1905 1906 /* Fill out the contents */ 1907 q->flags = NGQF_DATA; 1908 q->next = NULL; 1909 q->body.data.da_hook = hook; 1910 q->body.data.da_m = m; 1911 q->body.data.da_meta = meta; 1912 s = splhigh(); /* protect refs and queue */ 1913 hook->refs++; /* don't let it go away while on the queue */ 1914 1915 /* Put it on the queue */ 1916 if (ngqbase) { 1917 ngqlast->next = q; 1918 } else { 1919 ngqbase = q; 1920 } 1921 ngqlast = q; 1922 ngqsize++; 1923 splx(s); 1924 1925 /* Schedule software interrupt to handle it later */ 1926 schednetisr(NETISR_NETGRAPH); 1927 return (0); 1928 } 1929 1930 /* 1931 * Running at a raised (but we don't know which) processor priority level, 1932 * put the msg onto a queue to be picked up by another PPL (probably splnet) 1933 */ 1934 int 1935 ng_queue_msg(node_p here, struct ng_mesg *msg, const char *address) 1936 { 1937 struct ng_queue_entry *q; 1938 int s; 1939 node_p dest = NULL; 1940 char *retaddr = NULL; 1941 int error; 1942 1943 /* Find the target node. */ 1944 error = ng_path2node(here, address, &dest, &retaddr); 1945 if (error) { 1946 FREE(msg, M_NETGRAPH); 1947 return (error); 1948 } 1949 if ((q = ng_getqblk()) == NULL) { 1950 FREE(msg, M_NETGRAPH); 1951 if (retaddr) 1952 FREE(retaddr, M_NETGRAPH); 1953 return (ENOBUFS); 1954 } 1955 1956 /* Fill out the contents */ 1957 q->flags = NGQF_MESG; 1958 q->next = NULL; 1959 q->body.msg.msg_node = dest; 1960 q->body.msg.msg_msg = msg; 1961 q->body.msg.msg_retaddr = retaddr; 1962 s = splhigh(); /* protect refs and queue */ 1963 dest->refs++; /* don't let it go away while on the queue */ 1964 1965 /* Put it on the queue */ 1966 if (ngqbase) { 1967 ngqlast->next = q; 1968 } else { 1969 ngqbase = q; 1970 } 1971 ngqlast = q; 1972 ngqsize++; 1973 splx(s); 1974 1975 /* Schedule software interrupt to handle it later */ 1976 schednetisr(NETISR_NETGRAPH); 1977 return (0); 1978 } 1979 1980 /* 1981 * Pick an item off the queue, process it, and dispose of the queue entry. 1982 * Should be running at splnet. 1983 */ 1984 static void 1985 ngintr(void) 1986 { 1987 hook_p hook; 1988 struct ng_queue_entry *ngq; 1989 struct mbuf *m; 1990 meta_p meta; 1991 void *retaddr; 1992 struct ng_mesg *msg; 1993 node_p node; 1994 int error = 0; 1995 int s; 1996 1997 while (1) { 1998 s = splhigh(); 1999 if ((ngq = ngqbase)) { 2000 ngqbase = ngq->next; 2001 ngqsize--; 2002 } 2003 splx(s); 2004 if (ngq == NULL) 2005 return; 2006 switch (ngq->flags) { 2007 case NGQF_DATA: 2008 hook = ngq->body.data.da_hook; 2009 m = ngq->body.data.da_m; 2010 meta = ngq->body.data.da_meta; 2011 RETURN_QBLK(ngq); 2012 NG_SEND_DATAQ(error, hook, m, meta); 2013 ng_unref_hook(hook); 2014 break; 2015 case NGQF_MESG: 2016 node = ngq->body.msg.msg_node; 2017 msg = ngq->body.msg.msg_msg; 2018 retaddr = ngq->body.msg.msg_retaddr; 2019 RETURN_QBLK(ngq); 2020 if (node->flags & NG_INVALID) { 2021 FREE(msg, M_NETGRAPH); 2022 } else { 2023 CALL_MSG_HANDLER(error, node, msg, 2024 retaddr, NULL); 2025 } 2026 ng_unref(node); 2027 if (retaddr) 2028 FREE(retaddr, M_NETGRAPH); 2029 break; 2030 default: 2031 RETURN_QBLK(ngq); 2032 } 2033 } 2034 } 2035 2036 2037