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 * $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 <sys/sysctl.h> 59 #include <machine/limits.h> 60 61 #include <net/netisr.h> 62 63 #include <netgraph/ng_message.h> 64 #include <netgraph/netgraph.h> 65 #include <netgraph/ng_parse.h> 66 67 /* List of all nodes */ 68 static LIST_HEAD(, ng_node) nodelist; 69 70 /* List of installed types */ 71 static LIST_HEAD(, ng_type) typelist; 72 73 /* Hash releted definitions */ 74 #define ID_HASH_SIZE 32 /* most systems wont need even this many */ 75 static LIST_HEAD(, ng_node) ID_hash[ID_HASH_SIZE]; 76 /* Don't nead to initialise them because it's a LIST */ 77 78 /* Internal functions */ 79 static int ng_add_hook(node_p node, const char *name, hook_p * hookp); 80 static int ng_connect(hook_p hook1, hook_p hook2); 81 static void ng_disconnect_hook(hook_p hook); 82 static int ng_generic_msg(node_p here, struct ng_mesg *msg, 83 const char *retaddr, struct ng_mesg ** resp); 84 static ng_ID_t ng_decodeidname(const char *name); 85 static int ngb_mod_event(module_t mod, int event, void *data); 86 static void ngintr(void); 87 88 /* Our own netgraph malloc type */ 89 MALLOC_DEFINE(M_NETGRAPH, "netgraph", "netgraph structures and ctrl messages"); 90 91 /* Set this to Debugger("X") to catch all errors as they occur */ 92 #ifndef TRAP_ERROR 93 #define TRAP_ERROR 94 #endif 95 96 static ng_ID_t nextID = 1; 97 98 #ifdef INVARIANTS 99 #define CHECK_DATA_MBUF(m) do { \ 100 struct mbuf *n; \ 101 int total; \ 102 \ 103 if (((m)->m_flags & M_PKTHDR) == 0) \ 104 panic("%s: !PKTHDR", __FUNCTION__); \ 105 for (total = 0, n = (m); n != NULL; n = n->m_next) \ 106 total += n->m_len; \ 107 if ((m)->m_pkthdr.len != total) { \ 108 panic("%s: %d != %d", \ 109 __FUNCTION__, (m)->m_pkthdr.len, total); \ 110 } \ 111 } while (0) 112 #else 113 #define CHECK_DATA_MBUF(m) 114 #endif 115 116 117 /************************************************************************ 118 Parse type definitions for generic messages 119 ************************************************************************/ 120 121 /* Handy structure parse type defining macro */ 122 #define DEFINE_PARSE_STRUCT_TYPE(lo, up, args) \ 123 static const struct ng_parse_struct_field \ 124 ng_ ## lo ## _type_fields[] = NG_GENERIC_ ## up ## _INFO args; \ 125 static const struct ng_parse_type ng_generic_ ## lo ## _type = { \ 126 &ng_parse_struct_type, \ 127 &ng_ ## lo ## _type_fields \ 128 } 129 130 DEFINE_PARSE_STRUCT_TYPE(mkpeer, MKPEER, ()); 131 DEFINE_PARSE_STRUCT_TYPE(connect, CONNECT, ()); 132 DEFINE_PARSE_STRUCT_TYPE(name, NAME, ()); 133 DEFINE_PARSE_STRUCT_TYPE(rmhook, RMHOOK, ()); 134 DEFINE_PARSE_STRUCT_TYPE(nodeinfo, NODEINFO, ()); 135 DEFINE_PARSE_STRUCT_TYPE(typeinfo, TYPEINFO, ()); 136 DEFINE_PARSE_STRUCT_TYPE(linkinfo, LINKINFO, (&ng_generic_nodeinfo_type)); 137 138 /* Get length of an array when the length is stored as a 32 bit 139 value immediately preceeding the array -- as with struct namelist 140 and struct typelist. */ 141 static int 142 ng_generic_list_getLength(const struct ng_parse_type *type, 143 const u_char *start, const u_char *buf) 144 { 145 return *((const u_int32_t *)(buf - 4)); 146 } 147 148 /* Get length of the array of struct linkinfo inside a struct hooklist */ 149 static int 150 ng_generic_linkinfo_getLength(const struct ng_parse_type *type, 151 const u_char *start, const u_char *buf) 152 { 153 const struct hooklist *hl = (const struct hooklist *)start; 154 155 return hl->nodeinfo.hooks; 156 } 157 158 /* Array type for a variable length array of struct namelist */ 159 static const struct ng_parse_array_info ng_nodeinfoarray_type_info = { 160 &ng_generic_nodeinfo_type, 161 &ng_generic_list_getLength 162 }; 163 static const struct ng_parse_type ng_generic_nodeinfoarray_type = { 164 &ng_parse_array_type, 165 &ng_nodeinfoarray_type_info 166 }; 167 168 /* Array type for a variable length array of struct typelist */ 169 static const struct ng_parse_array_info ng_typeinfoarray_type_info = { 170 &ng_generic_typeinfo_type, 171 &ng_generic_list_getLength 172 }; 173 static const struct ng_parse_type ng_generic_typeinfoarray_type = { 174 &ng_parse_array_type, 175 &ng_typeinfoarray_type_info 176 }; 177 178 /* Array type for array of struct linkinfo in struct hooklist */ 179 static const struct ng_parse_array_info ng_generic_linkinfo_array_type_info = { 180 &ng_generic_linkinfo_type, 181 &ng_generic_linkinfo_getLength 182 }; 183 static const struct ng_parse_type ng_generic_linkinfo_array_type = { 184 &ng_parse_array_type, 185 &ng_generic_linkinfo_array_type_info 186 }; 187 188 DEFINE_PARSE_STRUCT_TYPE(typelist, TYPELIST, (&ng_generic_nodeinfoarray_type)); 189 DEFINE_PARSE_STRUCT_TYPE(hooklist, HOOKLIST, 190 (&ng_generic_nodeinfo_type, &ng_generic_linkinfo_array_type)); 191 DEFINE_PARSE_STRUCT_TYPE(listnodes, LISTNODES, 192 (&ng_generic_nodeinfoarray_type)); 193 194 /* List of commands and how to convert arguments to/from ASCII */ 195 static const struct ng_cmdlist ng_generic_cmds[] = { 196 { 197 NGM_GENERIC_COOKIE, 198 NGM_SHUTDOWN, 199 "shutdown", 200 NULL, 201 NULL 202 }, 203 { 204 NGM_GENERIC_COOKIE, 205 NGM_MKPEER, 206 "mkpeer", 207 &ng_generic_mkpeer_type, 208 NULL 209 }, 210 { 211 NGM_GENERIC_COOKIE, 212 NGM_CONNECT, 213 "connect", 214 &ng_generic_connect_type, 215 NULL 216 }, 217 { 218 NGM_GENERIC_COOKIE, 219 NGM_NAME, 220 "name", 221 &ng_generic_name_type, 222 NULL 223 }, 224 { 225 NGM_GENERIC_COOKIE, 226 NGM_RMHOOK, 227 "rmhook", 228 &ng_generic_rmhook_type, 229 NULL 230 }, 231 { 232 NGM_GENERIC_COOKIE, 233 NGM_NODEINFO, 234 "nodeinfo", 235 NULL, 236 &ng_generic_nodeinfo_type 237 }, 238 { 239 NGM_GENERIC_COOKIE, 240 NGM_LISTHOOKS, 241 "listhooks", 242 NULL, 243 &ng_generic_hooklist_type 244 }, 245 { 246 NGM_GENERIC_COOKIE, 247 NGM_LISTNAMES, 248 "listnames", 249 NULL, 250 &ng_generic_listnodes_type /* same as NGM_LISTNODES */ 251 }, 252 { 253 NGM_GENERIC_COOKIE, 254 NGM_LISTNODES, 255 "listnodes", 256 NULL, 257 &ng_generic_listnodes_type 258 }, 259 { 260 NGM_GENERIC_COOKIE, 261 NGM_LISTTYPES, 262 "listtypes", 263 NULL, 264 &ng_generic_typeinfo_type 265 }, 266 { 267 NGM_GENERIC_COOKIE, 268 NGM_TEXT_CONFIG, 269 "textconfig", 270 NULL, 271 &ng_parse_string_type 272 }, 273 { 274 NGM_GENERIC_COOKIE, 275 NGM_TEXT_STATUS, 276 "textstatus", 277 NULL, 278 &ng_parse_string_type 279 }, 280 { 281 NGM_GENERIC_COOKIE, 282 NGM_ASCII2BINARY, 283 "ascii2binary", 284 &ng_parse_ng_mesg_type, 285 &ng_parse_ng_mesg_type 286 }, 287 { 288 NGM_GENERIC_COOKIE, 289 NGM_BINARY2ASCII, 290 "binary2ascii", 291 &ng_parse_ng_mesg_type, 292 &ng_parse_ng_mesg_type 293 }, 294 { 0 } 295 }; 296 297 /************************************************************************ 298 Node routines 299 ************************************************************************/ 300 301 /* 302 * Instantiate a node of the requested type 303 */ 304 int 305 ng_make_node(const char *typename, node_p *nodepp) 306 { 307 struct ng_type *type; 308 309 /* Check that the type makes sense */ 310 if (typename == NULL) { 311 TRAP_ERROR; 312 return (EINVAL); 313 } 314 315 /* Locate the node type */ 316 if ((type = ng_findtype(typename)) == NULL) { 317 char *path, filename[NG_TYPELEN + 4]; 318 linker_file_t lf; 319 int error; 320 321 /* Not found, try to load it as a loadable module */ 322 snprintf(filename, sizeof(filename), "ng_%s.ko", typename); 323 if ((path = linker_search_path(filename)) == NULL) 324 return (ENXIO); 325 error = linker_load_file(path, &lf); 326 FREE(path, M_LINKER); 327 if (error != 0) 328 return (error); 329 lf->userrefs++; /* pretend loaded by the syscall */ 330 331 /* Try again, as now the type should have linked itself in */ 332 if ((type = ng_findtype(typename)) == NULL) 333 return (ENXIO); 334 } 335 336 /* Call the constructor */ 337 if (type->constructor != NULL) 338 return ((*type->constructor)(nodepp)); 339 else 340 return (ng_make_node_common(type, nodepp)); 341 } 342 343 /* 344 * Generic node creation. Called by node constructors. 345 * The returned node has a reference count of 1. 346 */ 347 int 348 ng_make_node_common(struct ng_type *type, node_p *nodepp) 349 { 350 node_p node; 351 352 /* Require the node type to have been already installed */ 353 if (ng_findtype(type->name) == NULL) { 354 TRAP_ERROR; 355 return (EINVAL); 356 } 357 358 /* Make a node and try attach it to the type */ 359 MALLOC(node, node_p, sizeof(*node), M_NETGRAPH, M_NOWAIT); 360 if (node == NULL) { 361 TRAP_ERROR; 362 return (ENOMEM); 363 } 364 bzero(node, sizeof(*node)); 365 node->type = type; 366 node->refs++; /* note reference */ 367 type->refs++; 368 369 /* Link us into the node linked list */ 370 LIST_INSERT_HEAD(&nodelist, node, nodes); 371 372 /* Initialize hook list for new node */ 373 LIST_INIT(&node->hooks); 374 375 /* get an ID and put us in the hash chain */ 376 node->ID = nextID++; /* 137 per second for 1 year before wrap */ 377 LIST_INSERT_HEAD(&ID_hash[node->ID % ID_HASH_SIZE], node, idnodes); 378 379 /* Done */ 380 *nodepp = node; 381 return (0); 382 } 383 384 /* 385 * Forceably start the shutdown process on a node. Either call 386 * it's shutdown method, or do the default shutdown if there is 387 * no type-specific method. 388 * 389 * Persistent nodes must have a type-specific method which 390 * resets the NG_INVALID flag. 391 */ 392 void 393 ng_rmnode(node_p node) 394 { 395 /* Check if it's already shutting down */ 396 if ((node->flags & NG_INVALID) != 0) 397 return; 398 399 /* Add an extra reference so it doesn't go away during this */ 400 node->refs++; 401 402 /* Mark it invalid so any newcomers know not to try use it */ 403 node->flags |= NG_INVALID; 404 405 /* Ask the type if it has anything to do in this case */ 406 if (node->type && node->type->shutdown) 407 (*node->type->shutdown)(node); 408 else { /* do the default thing */ 409 ng_unname(node); 410 ng_cutlinks(node); 411 ng_unref(node); 412 } 413 414 /* Remove extra reference, possibly the last */ 415 ng_unref(node); 416 } 417 418 /* 419 * Called by the destructor to remove any STANDARD external references 420 */ 421 void 422 ng_cutlinks(node_p node) 423 { 424 hook_p hook; 425 426 /* Make sure that this is set to stop infinite loops */ 427 node->flags |= NG_INVALID; 428 429 /* If we have sleepers, wake them up; they'll see NG_INVALID */ 430 if (node->sleepers) 431 wakeup(node); 432 433 /* Notify all remaining connected nodes to disconnect */ 434 while ((hook = LIST_FIRST(&node->hooks)) != NULL) 435 ng_destroy_hook(hook); 436 } 437 438 /* 439 * Remove a reference to the node, possibly the last 440 */ 441 void 442 ng_unref(node_p node) 443 { 444 int s; 445 446 s = splhigh(); 447 if (--node->refs <= 0) { 448 node->type->refs--; 449 LIST_REMOVE(node, nodes); 450 LIST_REMOVE(node, idnodes); 451 FREE(node, M_NETGRAPH); 452 } 453 splx(s); 454 } 455 456 /* 457 * Wait for a node to come ready. Returns a node with a reference count; 458 * don't forget to drop it when we are done with it using ng_release_node(). 459 */ 460 int 461 ng_wait_node(node_p node, char *msg) 462 { 463 int s, error = 0; 464 465 if (msg == NULL) 466 msg = "netgraph"; 467 s = splnet(); 468 node->sleepers++; 469 node->refs++; /* the sleeping process counts as a reference */ 470 while ((node->flags & (NG_BUSY | NG_INVALID)) == NG_BUSY) 471 error = tsleep(node, (PZERO + 1) | PCATCH, msg, 0); 472 node->sleepers--; 473 if (node->flags & NG_INVALID) { 474 TRAP_ERROR; 475 error = ENXIO; 476 } else { 477 KASSERT(node->refs > 1, 478 ("%s: refs=%d", __FUNCTION__, node->refs)); 479 node->flags |= NG_BUSY; 480 } 481 splx(s); 482 483 /* Release the reference we had on it */ 484 if (error != 0) 485 ng_unref(node); 486 return error; 487 } 488 489 /* 490 * Release a node acquired via ng_wait_node() 491 */ 492 void 493 ng_release_node(node_p node) 494 { 495 /* Declare that we don't want it */ 496 node->flags &= ~NG_BUSY; 497 498 /* If we have sleepers, then wake them up */ 499 if (node->sleepers) 500 wakeup(node); 501 502 /* We also have a reference.. drop it too */ 503 ng_unref(node); 504 } 505 506 /************************************************************************ 507 Node ID handling 508 ************************************************************************/ 509 static node_p 510 ng_ID2node(ng_ID_t ID) 511 { 512 node_p np; 513 LIST_FOREACH(np, &ID_hash[ID % ID_HASH_SIZE], idnodes) { 514 if ((np->flags & NG_INVALID) == 0 && np->ID == ID) 515 break; 516 } 517 return(np); 518 } 519 520 ng_ID_t 521 ng_node2ID(node_p node) 522 { 523 return (node->ID); 524 } 525 526 /************************************************************************ 527 Node name handling 528 ************************************************************************/ 529 530 /* 531 * Assign a node a name. Once assigned, the name cannot be changed. 532 */ 533 int 534 ng_name_node(node_p node, const char *name) 535 { 536 int i; 537 538 /* Check the name is valid */ 539 for (i = 0; i < NG_NODELEN + 1; i++) { 540 if (name[i] == '\0' || name[i] == '.' || name[i] == ':') 541 break; 542 } 543 if (i == 0 || name[i] != '\0') { 544 TRAP_ERROR; 545 return (EINVAL); 546 } 547 if (ng_decodeidname(name) != 0) { /* valid IDs not allowed here */ 548 TRAP_ERROR; 549 return (EINVAL); 550 } 551 552 /* Check the node isn't already named */ 553 if (node->name != NULL) { 554 TRAP_ERROR; 555 return (EISCONN); 556 } 557 558 /* Check the name isn't already being used */ 559 if (ng_findname(node, name) != NULL) { 560 TRAP_ERROR; 561 return (EADDRINUSE); 562 } 563 564 /* Allocate space and copy it */ 565 MALLOC(node->name, char *, strlen(name) + 1, M_NETGRAPH, M_NOWAIT); 566 if (node->name == NULL) { 567 TRAP_ERROR; 568 return (ENOMEM); 569 } 570 strcpy(node->name, name); 571 572 /* The name counts as a reference */ 573 node->refs++; 574 return (0); 575 } 576 577 /* 578 * Find a node by absolute name. The name should NOT end with ':' 579 * The name "." means "this node" and "[xxx]" means "the node 580 * with ID (ie, at address) xxx". 581 * 582 * Returns the node if found, else NULL. 583 */ 584 node_p 585 ng_findname(node_p this, const char *name) 586 { 587 node_p node; 588 ng_ID_t temp; 589 590 /* "." means "this node" */ 591 if (strcmp(name, ".") == 0) 592 return(this); 593 594 /* Check for name-by-ID */ 595 if ((temp = ng_decodeidname(name)) != 0) { 596 return (ng_ID2node(temp)); 597 } 598 599 /* Find node by name */ 600 LIST_FOREACH(node, &nodelist, nodes) { 601 if ((node->name != NULL) 602 && (strcmp(node->name, name) == 0) 603 && ((node->flags & NG_INVALID) == 0)) 604 break; 605 } 606 return (node); 607 } 608 609 /* 610 * Decode a ID name, eg. "[f03034de]". Returns 0 if the 611 * string is not valid, otherwise returns the value. 612 */ 613 static ng_ID_t 614 ng_decodeidname(const char *name) 615 { 616 const int len = strlen(name); 617 char *eptr; 618 u_long val; 619 620 /* Check for proper length, brackets, no leading junk */ 621 if (len < 3 || name[0] != '[' || name[len - 1] != ']' 622 || !isxdigit(name[1])) 623 return (0); 624 625 /* Decode number */ 626 val = strtoul(name + 1, &eptr, 16); 627 if (eptr - name != len - 1 || val == ULONG_MAX || val == 0) 628 return ((ng_ID_t)0); 629 return (ng_ID_t)val; 630 } 631 632 /* 633 * Remove a name from a node. This should only be called 634 * when shutting down and removing the node. 635 */ 636 void 637 ng_unname(node_p node) 638 { 639 if (node->name) { 640 FREE(node->name, M_NETGRAPH); 641 node->name = NULL; 642 ng_unref(node); 643 } 644 } 645 646 /************************************************************************ 647 Hook routines 648 649 Names are not optional. Hooks are always connected, except for a 650 brief moment within these routines. 651 652 ************************************************************************/ 653 654 /* 655 * Remove a hook reference 656 */ 657 void 658 ng_unref_hook(hook_p hook) 659 { 660 int s; 661 662 s = splhigh(); 663 if (--hook->refs == 0) 664 FREE(hook, M_NETGRAPH); 665 splx(s); 666 } 667 668 /* 669 * Add an unconnected hook to a node. Only used internally. 670 */ 671 static int 672 ng_add_hook(node_p node, const char *name, hook_p *hookp) 673 { 674 hook_p hook; 675 int error = 0; 676 677 /* Check that the given name is good */ 678 if (name == NULL) { 679 TRAP_ERROR; 680 return (EINVAL); 681 } 682 if (ng_findhook(node, name) != NULL) { 683 TRAP_ERROR; 684 return (EEXIST); 685 } 686 687 /* Allocate the hook and link it up */ 688 MALLOC(hook, hook_p, sizeof(*hook), M_NETGRAPH, M_NOWAIT); 689 if (hook == NULL) { 690 TRAP_ERROR; 691 return (ENOMEM); 692 } 693 bzero(hook, sizeof(*hook)); 694 hook->refs = 1; 695 hook->flags = HK_INVALID; 696 hook->node = node; 697 node->refs++; /* each hook counts as a reference */ 698 699 /* Check if the node type code has something to say about it */ 700 if (node->type->newhook != NULL) 701 if ((error = (*node->type->newhook)(node, hook, name)) != 0) 702 goto fail; 703 704 /* 705 * The 'type' agrees so far, so go ahead and link it in. 706 * We'll ask again later when we actually connect the hooks. 707 */ 708 LIST_INSERT_HEAD(&node->hooks, hook, hooks); 709 node->numhooks++; 710 711 /* Set hook name */ 712 MALLOC(hook->name, char *, strlen(name) + 1, M_NETGRAPH, M_NOWAIT); 713 if (hook->name == NULL) { 714 error = ENOMEM; 715 LIST_REMOVE(hook, hooks); 716 node->numhooks--; 717 fail: 718 hook->node = NULL; 719 ng_unref(node); 720 ng_unref_hook(hook); /* this frees the hook */ 721 return (error); 722 } 723 strcpy(hook->name, name); 724 if (hookp) 725 *hookp = hook; 726 return (error); 727 } 728 729 /* 730 * Connect a pair of hooks. Only used internally. 731 */ 732 static int 733 ng_connect(hook_p hook1, hook_p hook2) 734 { 735 int error; 736 737 hook1->peer = hook2; 738 hook2->peer = hook1; 739 740 /* Give each node the opportunity to veto the impending connection */ 741 if (hook1->node->type->connect) { 742 if ((error = (*hook1->node->type->connect) (hook1))) { 743 ng_destroy_hook(hook1); /* also zaps hook2 */ 744 return (error); 745 } 746 } 747 if (hook2->node->type->connect) { 748 if ((error = (*hook2->node->type->connect) (hook2))) { 749 ng_destroy_hook(hook2); /* also zaps hook1 */ 750 return (error); 751 } 752 } 753 hook1->flags &= ~HK_INVALID; 754 hook2->flags &= ~HK_INVALID; 755 return (0); 756 } 757 758 /* 759 * Find a hook 760 * 761 * Node types may supply their own optimized routines for finding 762 * hooks. If none is supplied, we just do a linear search. 763 */ 764 hook_p 765 ng_findhook(node_p node, const char *name) 766 { 767 hook_p hook; 768 769 if (node->type->findhook != NULL) 770 return (*node->type->findhook)(node, name); 771 LIST_FOREACH(hook, &node->hooks, hooks) { 772 if (hook->name != NULL 773 && strcmp(hook->name, name) == 0 774 && (hook->flags & HK_INVALID) == 0) 775 return (hook); 776 } 777 return (NULL); 778 } 779 780 /* 781 * Destroy a hook 782 * 783 * As hooks are always attached, this really destroys two hooks. 784 * The one given, and the one attached to it. Disconnect the hooks 785 * from each other first. 786 */ 787 void 788 ng_destroy_hook(hook_p hook) 789 { 790 hook_p peer = hook->peer; 791 792 hook->flags |= HK_INVALID; /* as soon as possible */ 793 if (peer) { 794 peer->flags |= HK_INVALID; /* as soon as possible */ 795 hook->peer = NULL; 796 peer->peer = NULL; 797 ng_disconnect_hook(peer); 798 } 799 ng_disconnect_hook(hook); 800 } 801 802 /* 803 * Notify the node of the hook's demise. This may result in more actions 804 * (e.g. shutdown) but we don't do that ourselves and don't know what 805 * happens there. If there is no appropriate handler, then just remove it 806 * (and decrement the reference count of it's node which in turn might 807 * make something happen). 808 */ 809 static void 810 ng_disconnect_hook(hook_p hook) 811 { 812 node_p node = hook->node; 813 814 /* 815 * Remove the hook from the node's list to avoid possible recursion 816 * in case the disconnection results in node shutdown. 817 */ 818 LIST_REMOVE(hook, hooks); 819 node->numhooks--; 820 if (node->type->disconnect) { 821 /* 822 * The type handler may elect to destroy the peer so don't 823 * trust its existance after this point. 824 */ 825 (*node->type->disconnect) (hook); 826 } 827 ng_unref(node); /* might be the last reference */ 828 if (hook->name) 829 FREE(hook->name, M_NETGRAPH); 830 hook->node = NULL; /* may still be referenced elsewhere */ 831 ng_unref_hook(hook); 832 } 833 834 /* 835 * Take two hooks on a node and merge the connection so that the given node 836 * is effectively bypassed. 837 */ 838 int 839 ng_bypass(hook_p hook1, hook_p hook2) 840 { 841 if (hook1->node != hook2->node) 842 return (EINVAL); 843 hook1->peer->peer = hook2->peer; 844 hook2->peer->peer = hook1->peer; 845 846 /* XXX If we ever cache methods on hooks update them as well */ 847 hook1->peer = NULL; 848 hook2->peer = NULL; 849 ng_destroy_hook(hook1); 850 ng_destroy_hook(hook2); 851 return (0); 852 } 853 854 /* 855 * Install a new netgraph type 856 */ 857 int 858 ng_newtype(struct ng_type *tp) 859 { 860 const size_t namelen = strlen(tp->name); 861 862 /* Check version and type name fields */ 863 if (tp->version != NG_VERSION || namelen == 0 || namelen > NG_TYPELEN) { 864 TRAP_ERROR; 865 return (EINVAL); 866 } 867 868 /* Check for name collision */ 869 if (ng_findtype(tp->name) != NULL) { 870 TRAP_ERROR; 871 return (EEXIST); 872 } 873 874 /* Link in new type */ 875 LIST_INSERT_HEAD(&typelist, tp, types); 876 tp->refs = 1; /* first ref is linked list */ 877 return (0); 878 } 879 880 /* 881 * Look for a type of the name given 882 */ 883 struct ng_type * 884 ng_findtype(const char *typename) 885 { 886 struct ng_type *type; 887 888 LIST_FOREACH(type, &typelist, types) { 889 if (strcmp(type->name, typename) == 0) 890 break; 891 } 892 return (type); 893 } 894 895 896 /************************************************************************ 897 Composite routines 898 ************************************************************************/ 899 900 /* 901 * Make a peer and connect. The order is arranged to minimise 902 * the work needed to back out in case of error. 903 */ 904 int 905 ng_mkpeer(node_p node, const char *name, const char *name2, char *type) 906 { 907 node_p node2; 908 hook_p hook; 909 hook_p hook2; 910 int error; 911 912 if ((error = ng_add_hook(node, name, &hook))) 913 return (error); 914 if ((error = ng_make_node(type, &node2))) { 915 ng_destroy_hook(hook); 916 return (error); 917 } 918 if ((error = ng_add_hook(node2, name2, &hook2))) { 919 ng_rmnode(node2); 920 ng_destroy_hook(hook); 921 return (error); 922 } 923 924 /* 925 * Actually link the two hooks together.. on failure they are 926 * destroyed so we don't have to do that here. 927 */ 928 if ((error = ng_connect(hook, hook2))) 929 ng_rmnode(node2); 930 return (error); 931 } 932 933 /* 934 * Connect two nodes using the specified hooks 935 */ 936 int 937 ng_con_nodes(node_p node, const char *name, node_p node2, const char *name2) 938 { 939 int error; 940 hook_p hook; 941 hook_p hook2; 942 943 if ((error = ng_add_hook(node, name, &hook))) 944 return (error); 945 if ((error = ng_add_hook(node2, name2, &hook2))) { 946 ng_destroy_hook(hook); 947 return (error); 948 } 949 return (ng_connect(hook, hook2)); 950 } 951 952 /* 953 * Parse and verify a string of the form: <NODE:><PATH> 954 * 955 * Such a string can refer to a specific node or a specific hook 956 * on a specific node, depending on how you look at it. In the 957 * latter case, the PATH component must not end in a dot. 958 * 959 * Both <NODE:> and <PATH> are optional. The <PATH> is a string 960 * of hook names separated by dots. This breaks out the original 961 * string, setting *nodep to "NODE" (or NULL if none) and *pathp 962 * to "PATH" (or NULL if degenerate). Also, *hookp will point to 963 * the final hook component of <PATH>, if any, otherwise NULL. 964 * 965 * This returns -1 if the path is malformed. The char ** are optional. 966 */ 967 968 int 969 ng_path_parse(char *addr, char **nodep, char **pathp, char **hookp) 970 { 971 char *node, *path, *hook; 972 int k; 973 974 /* 975 * Extract absolute NODE, if any 976 */ 977 for (path = addr; *path && *path != ':'; path++); 978 if (*path) { 979 node = addr; /* Here's the NODE */ 980 *path++ = '\0'; /* Here's the PATH */ 981 982 /* Node name must not be empty */ 983 if (!*node) 984 return -1; 985 986 /* A name of "." is OK; otherwise '.' not allowed */ 987 if (strcmp(node, ".") != 0) { 988 for (k = 0; node[k]; k++) 989 if (node[k] == '.') 990 return -1; 991 } 992 } else { 993 node = NULL; /* No absolute NODE */ 994 path = addr; /* Here's the PATH */ 995 } 996 997 /* Snoop for illegal characters in PATH */ 998 for (k = 0; path[k]; k++) 999 if (path[k] == ':') 1000 return -1; 1001 1002 /* Check for no repeated dots in PATH */ 1003 for (k = 0; path[k]; k++) 1004 if (path[k] == '.' && path[k + 1] == '.') 1005 return -1; 1006 1007 /* Remove extra (degenerate) dots from beginning or end of PATH */ 1008 if (path[0] == '.') 1009 path++; 1010 if (*path && path[strlen(path) - 1] == '.') 1011 path[strlen(path) - 1] = 0; 1012 1013 /* If PATH has a dot, then we're not talking about a hook */ 1014 if (*path) { 1015 for (hook = path, k = 0; path[k]; k++) 1016 if (path[k] == '.') { 1017 hook = NULL; 1018 break; 1019 } 1020 } else 1021 path = hook = NULL; 1022 1023 /* Done */ 1024 if (nodep) 1025 *nodep = node; 1026 if (pathp) 1027 *pathp = path; 1028 if (hookp) 1029 *hookp = hook; 1030 return (0); 1031 } 1032 1033 /* 1034 * Given a path, which may be absolute or relative, and a starting node, 1035 * return the destination node. Compute the "return address" if desired. 1036 */ 1037 int 1038 ng_path2node(node_p here, const char *address, node_p *destp, char **rtnp) 1039 { 1040 const node_p start = here; 1041 char fullpath[NG_PATHLEN + 1]; 1042 char *nodename, *path, pbuf[2]; 1043 node_p node; 1044 char *cp; 1045 1046 /* Initialize */ 1047 if (rtnp) 1048 *rtnp = NULL; 1049 if (destp == NULL) 1050 return EINVAL; 1051 *destp = NULL; 1052 1053 /* Make a writable copy of address for ng_path_parse() */ 1054 strncpy(fullpath, address, sizeof(fullpath) - 1); 1055 fullpath[sizeof(fullpath) - 1] = '\0'; 1056 1057 /* Parse out node and sequence of hooks */ 1058 if (ng_path_parse(fullpath, &nodename, &path, NULL) < 0) { 1059 TRAP_ERROR; 1060 return EINVAL; 1061 } 1062 if (path == NULL) { 1063 pbuf[0] = '.'; /* Needs to be writable */ 1064 pbuf[1] = '\0'; 1065 path = pbuf; 1066 } 1067 1068 /* For an absolute address, jump to the starting node */ 1069 if (nodename) { 1070 node = ng_findname(here, nodename); 1071 if (node == NULL) { 1072 TRAP_ERROR; 1073 return (ENOENT); 1074 } 1075 } else 1076 node = here; 1077 1078 /* Now follow the sequence of hooks */ 1079 for (cp = path; node != NULL && *cp != '\0'; ) { 1080 hook_p hook; 1081 char *segment; 1082 1083 /* 1084 * Break out the next path segment. Replace the dot we just 1085 * found with a NUL; "cp" points to the next segment (or the 1086 * NUL at the end). 1087 */ 1088 for (segment = cp; *cp != '\0'; cp++) { 1089 if (*cp == '.') { 1090 *cp++ = '\0'; 1091 break; 1092 } 1093 } 1094 1095 /* Empty segment */ 1096 if (*segment == '\0') 1097 continue; 1098 1099 /* We have a segment, so look for a hook by that name */ 1100 hook = ng_findhook(node, segment); 1101 1102 /* Can't get there from here... */ 1103 if (hook == NULL 1104 || hook->peer == NULL 1105 || (hook->flags & HK_INVALID) != 0) { 1106 TRAP_ERROR; 1107 return (ENOENT); 1108 } 1109 1110 /* Hop on over to the next node */ 1111 node = hook->peer->node; 1112 } 1113 1114 /* If node somehow missing, fail here (probably this is not needed) */ 1115 if (node == NULL) { 1116 TRAP_ERROR; 1117 return (ENXIO); 1118 } 1119 1120 /* Now compute return address, i.e., the path to the sender */ 1121 if (rtnp != NULL) { 1122 MALLOC(*rtnp, char *, NG_NODELEN + 2, M_NETGRAPH, M_NOWAIT); 1123 if (*rtnp == NULL) { 1124 TRAP_ERROR; 1125 return (ENOMEM); 1126 } 1127 if (start->name != NULL) 1128 sprintf(*rtnp, "%s:", start->name); 1129 else 1130 sprintf(*rtnp, "[%x]:", ng_node2ID(start)); 1131 } 1132 1133 /* Done */ 1134 *destp = node; 1135 return (0); 1136 } 1137 1138 /* 1139 * Call the appropriate message handler for the object. 1140 * It is up to the message handler to free the message. 1141 * If it's a generic message, handle it generically, otherwise 1142 * call the type's message handler (if it exists) 1143 * XXX (race). Remember that a queued message may reference a node 1144 * or hook that has just been invalidated. It will exist 1145 * as the queue code is holding a reference, but.. 1146 */ 1147 1148 #define CALL_MSG_HANDLER(error, node, msg, retaddr, resp) \ 1149 do { \ 1150 if((msg)->header.typecookie == NGM_GENERIC_COOKIE) { \ 1151 (error) = ng_generic_msg((node), (msg), \ 1152 (retaddr), (resp)); \ 1153 } else { \ 1154 if ((node)->type->rcvmsg != NULL) { \ 1155 (error) = (*(node)->type->rcvmsg)((node), \ 1156 (msg), (retaddr), (resp)); \ 1157 } else { \ 1158 TRAP_ERROR; \ 1159 FREE((msg), M_NETGRAPH); \ 1160 (error) = EINVAL; \ 1161 } \ 1162 } \ 1163 } while (0) 1164 1165 1166 /* 1167 * Send a control message to a node 1168 */ 1169 int 1170 ng_send_msg(node_p here, struct ng_mesg *msg, const char *address, 1171 struct ng_mesg **rptr) 1172 { 1173 node_p dest = NULL; 1174 char *retaddr = NULL; 1175 int error; 1176 1177 /* Find the target node */ 1178 error = ng_path2node(here, address, &dest, &retaddr); 1179 if (error) { 1180 FREE(msg, M_NETGRAPH); 1181 return error; 1182 } 1183 1184 /* Make sure the resp field is null before we start */ 1185 if (rptr != NULL) 1186 *rptr = NULL; 1187 1188 CALL_MSG_HANDLER(error, dest, msg, retaddr, rptr); 1189 1190 /* Make sure that if there is a response, it has the RESP bit set */ 1191 if ((error == 0) && rptr && *rptr) 1192 (*rptr)->header.flags |= NGF_RESP; 1193 1194 /* 1195 * If we had a return address it is up to us to free it. They should 1196 * have taken a copy if they needed to make a delayed response. 1197 */ 1198 if (retaddr) 1199 FREE(retaddr, M_NETGRAPH); 1200 return (error); 1201 } 1202 1203 /* 1204 * Implement the 'generic' control messages 1205 */ 1206 static int 1207 ng_generic_msg(node_p here, struct ng_mesg *msg, const char *retaddr, 1208 struct ng_mesg **resp) 1209 { 1210 int error = 0; 1211 1212 if (msg->header.typecookie != NGM_GENERIC_COOKIE) { 1213 TRAP_ERROR; 1214 FREE(msg, M_NETGRAPH); 1215 return (EINVAL); 1216 } 1217 switch (msg->header.cmd) { 1218 case NGM_SHUTDOWN: 1219 ng_rmnode(here); 1220 break; 1221 case NGM_MKPEER: 1222 { 1223 struct ngm_mkpeer *const mkp = (struct ngm_mkpeer *) msg->data; 1224 1225 if (msg->header.arglen != sizeof(*mkp)) { 1226 TRAP_ERROR; 1227 return (EINVAL); 1228 } 1229 mkp->type[sizeof(mkp->type) - 1] = '\0'; 1230 mkp->ourhook[sizeof(mkp->ourhook) - 1] = '\0'; 1231 mkp->peerhook[sizeof(mkp->peerhook) - 1] = '\0'; 1232 error = ng_mkpeer(here, mkp->ourhook, mkp->peerhook, mkp->type); 1233 break; 1234 } 1235 case NGM_CONNECT: 1236 { 1237 struct ngm_connect *const con = 1238 (struct ngm_connect *) msg->data; 1239 node_p node2; 1240 1241 if (msg->header.arglen != sizeof(*con)) { 1242 TRAP_ERROR; 1243 return (EINVAL); 1244 } 1245 con->path[sizeof(con->path) - 1] = '\0'; 1246 con->ourhook[sizeof(con->ourhook) - 1] = '\0'; 1247 con->peerhook[sizeof(con->peerhook) - 1] = '\0'; 1248 error = ng_path2node(here, con->path, &node2, NULL); 1249 if (error) 1250 break; 1251 error = ng_con_nodes(here, con->ourhook, node2, con->peerhook); 1252 break; 1253 } 1254 case NGM_NAME: 1255 { 1256 struct ngm_name *const nam = (struct ngm_name *) msg->data; 1257 1258 if (msg->header.arglen != sizeof(*nam)) { 1259 TRAP_ERROR; 1260 return (EINVAL); 1261 } 1262 nam->name[sizeof(nam->name) - 1] = '\0'; 1263 error = ng_name_node(here, nam->name); 1264 break; 1265 } 1266 case NGM_RMHOOK: 1267 { 1268 struct ngm_rmhook *const rmh = (struct ngm_rmhook *) msg->data; 1269 hook_p hook; 1270 1271 if (msg->header.arglen != sizeof(*rmh)) { 1272 TRAP_ERROR; 1273 return (EINVAL); 1274 } 1275 rmh->ourhook[sizeof(rmh->ourhook) - 1] = '\0'; 1276 if ((hook = ng_findhook(here, rmh->ourhook)) != NULL) 1277 ng_destroy_hook(hook); 1278 break; 1279 } 1280 case NGM_NODEINFO: 1281 { 1282 struct nodeinfo *ni; 1283 struct ng_mesg *rp; 1284 1285 /* Get response struct */ 1286 if (resp == NULL) { 1287 error = EINVAL; 1288 break; 1289 } 1290 NG_MKRESPONSE(rp, msg, sizeof(*ni), M_NOWAIT); 1291 if (rp == NULL) { 1292 error = ENOMEM; 1293 break; 1294 } 1295 1296 /* Fill in node info */ 1297 ni = (struct nodeinfo *) rp->data; 1298 if (here->name != NULL) 1299 strncpy(ni->name, here->name, NG_NODELEN); 1300 strncpy(ni->type, here->type->name, NG_TYPELEN); 1301 ni->id = ng_node2ID(here); 1302 ni->hooks = here->numhooks; 1303 *resp = rp; 1304 break; 1305 } 1306 case NGM_LISTHOOKS: 1307 { 1308 const int nhooks = here->numhooks; 1309 struct hooklist *hl; 1310 struct nodeinfo *ni; 1311 struct ng_mesg *rp; 1312 hook_p hook; 1313 1314 /* Get response struct */ 1315 if (resp == NULL) { 1316 error = EINVAL; 1317 break; 1318 } 1319 NG_MKRESPONSE(rp, msg, sizeof(*hl) 1320 + (nhooks * sizeof(struct linkinfo)), M_NOWAIT); 1321 if (rp == NULL) { 1322 error = ENOMEM; 1323 break; 1324 } 1325 hl = (struct hooklist *) rp->data; 1326 ni = &hl->nodeinfo; 1327 1328 /* Fill in node info */ 1329 if (here->name) 1330 strncpy(ni->name, here->name, NG_NODELEN); 1331 strncpy(ni->type, here->type->name, NG_TYPELEN); 1332 ni->id = ng_node2ID(here); 1333 1334 /* Cycle through the linked list of hooks */ 1335 ni->hooks = 0; 1336 LIST_FOREACH(hook, &here->hooks, hooks) { 1337 struct linkinfo *const link = &hl->link[ni->hooks]; 1338 1339 if (ni->hooks >= nhooks) { 1340 log(LOG_ERR, "%s: number of %s changed\n", 1341 __FUNCTION__, "hooks"); 1342 break; 1343 } 1344 if ((hook->flags & HK_INVALID) != 0) 1345 continue; 1346 strncpy(link->ourhook, hook->name, NG_HOOKLEN); 1347 strncpy(link->peerhook, hook->peer->name, NG_HOOKLEN); 1348 if (hook->peer->node->name != NULL) 1349 strncpy(link->nodeinfo.name, 1350 hook->peer->node->name, NG_NODELEN); 1351 strncpy(link->nodeinfo.type, 1352 hook->peer->node->type->name, NG_TYPELEN); 1353 link->nodeinfo.id = ng_node2ID(hook->peer->node); 1354 link->nodeinfo.hooks = hook->peer->node->numhooks; 1355 ni->hooks++; 1356 } 1357 *resp = rp; 1358 break; 1359 } 1360 1361 case NGM_LISTNAMES: 1362 case NGM_LISTNODES: 1363 { 1364 const int unnamed = (msg->header.cmd == NGM_LISTNODES); 1365 struct namelist *nl; 1366 struct ng_mesg *rp; 1367 node_p node; 1368 int num = 0; 1369 1370 if (resp == NULL) { 1371 error = EINVAL; 1372 break; 1373 } 1374 1375 /* Count number of nodes */ 1376 LIST_FOREACH(node, &nodelist, nodes) { 1377 if ((node->flags & NG_INVALID) == 0 1378 && (unnamed || node->name != NULL)) 1379 num++; 1380 } 1381 1382 /* Get response struct */ 1383 if (resp == NULL) { 1384 error = EINVAL; 1385 break; 1386 } 1387 NG_MKRESPONSE(rp, msg, sizeof(*nl) 1388 + (num * sizeof(struct nodeinfo)), M_NOWAIT); 1389 if (rp == NULL) { 1390 error = ENOMEM; 1391 break; 1392 } 1393 nl = (struct namelist *) rp->data; 1394 1395 /* Cycle through the linked list of nodes */ 1396 nl->numnames = 0; 1397 LIST_FOREACH(node, &nodelist, nodes) { 1398 struct nodeinfo *const np = &nl->nodeinfo[nl->numnames]; 1399 1400 if (nl->numnames >= num) { 1401 log(LOG_ERR, "%s: number of %s changed\n", 1402 __FUNCTION__, "nodes"); 1403 break; 1404 } 1405 if ((node->flags & NG_INVALID) != 0) 1406 continue; 1407 if (!unnamed && node->name == NULL) 1408 continue; 1409 if (node->name != NULL) 1410 strncpy(np->name, node->name, NG_NODELEN); 1411 strncpy(np->type, node->type->name, NG_TYPELEN); 1412 np->id = ng_node2ID(node); 1413 np->hooks = node->numhooks; 1414 nl->numnames++; 1415 } 1416 *resp = rp; 1417 break; 1418 } 1419 1420 case NGM_LISTTYPES: 1421 { 1422 struct typelist *tl; 1423 struct ng_mesg *rp; 1424 struct ng_type *type; 1425 int num = 0; 1426 1427 if (resp == NULL) { 1428 error = EINVAL; 1429 break; 1430 } 1431 1432 /* Count number of types */ 1433 LIST_FOREACH(type, &typelist, types) 1434 num++; 1435 1436 /* Get response struct */ 1437 if (resp == NULL) { 1438 error = EINVAL; 1439 break; 1440 } 1441 NG_MKRESPONSE(rp, msg, sizeof(*tl) 1442 + (num * sizeof(struct typeinfo)), M_NOWAIT); 1443 if (rp == NULL) { 1444 error = ENOMEM; 1445 break; 1446 } 1447 tl = (struct typelist *) rp->data; 1448 1449 /* Cycle through the linked list of types */ 1450 tl->numtypes = 0; 1451 LIST_FOREACH(type, &typelist, types) { 1452 struct typeinfo *const tp = &tl->typeinfo[tl->numtypes]; 1453 1454 if (tl->numtypes >= num) { 1455 log(LOG_ERR, "%s: number of %s changed\n", 1456 __FUNCTION__, "types"); 1457 break; 1458 } 1459 strncpy(tp->type_name, type->name, NG_TYPELEN); 1460 tp->numnodes = type->refs - 1; /* don't count list */ 1461 tl->numtypes++; 1462 } 1463 *resp = rp; 1464 break; 1465 } 1466 1467 case NGM_BINARY2ASCII: 1468 { 1469 int bufSize = 20 * 1024; /* XXX hard coded constant */ 1470 const struct ng_parse_type *argstype; 1471 const struct ng_cmdlist *c; 1472 struct ng_mesg *rp, *binary, *ascii; 1473 1474 /* Data area must contain a valid netgraph message */ 1475 binary = (struct ng_mesg *)msg->data; 1476 if (msg->header.arglen < sizeof(struct ng_mesg) 1477 || msg->header.arglen - sizeof(struct ng_mesg) 1478 < binary->header.arglen) { 1479 error = EINVAL; 1480 break; 1481 } 1482 1483 /* Get a response message with lots of room */ 1484 NG_MKRESPONSE(rp, msg, sizeof(*ascii) + bufSize, M_NOWAIT); 1485 if (rp == NULL) { 1486 error = ENOMEM; 1487 break; 1488 } 1489 ascii = (struct ng_mesg *)rp->data; 1490 1491 /* Copy binary message header to response message payload */ 1492 bcopy(binary, ascii, sizeof(*binary)); 1493 1494 /* Find command by matching typecookie and command number */ 1495 for (c = here->type->cmdlist; 1496 c != NULL && c->name != NULL; c++) { 1497 if (binary->header.typecookie == c->cookie 1498 && binary->header.cmd == c->cmd) 1499 break; 1500 } 1501 if (c == NULL || c->name == NULL) { 1502 for (c = ng_generic_cmds; c->name != NULL; c++) { 1503 if (binary->header.typecookie == c->cookie 1504 && binary->header.cmd == c->cmd) 1505 break; 1506 } 1507 if (c->name == NULL) { 1508 FREE(rp, M_NETGRAPH); 1509 error = ENOSYS; 1510 break; 1511 } 1512 } 1513 1514 /* Convert command name to ASCII */ 1515 snprintf(ascii->header.cmdstr, sizeof(ascii->header.cmdstr), 1516 "%s", c->name); 1517 1518 /* Convert command arguments to ASCII */ 1519 argstype = (binary->header.flags & NGF_RESP) ? 1520 c->respType : c->mesgType; 1521 if (argstype == NULL) 1522 *ascii->data = '\0'; 1523 else { 1524 if ((error = ng_unparse(argstype, 1525 (u_char *)binary->data, 1526 ascii->data, bufSize)) != 0) { 1527 FREE(rp, M_NETGRAPH); 1528 break; 1529 } 1530 } 1531 1532 /* Return the result as struct ng_mesg plus ASCII string */ 1533 bufSize = strlen(ascii->data) + 1; 1534 ascii->header.arglen = bufSize; 1535 rp->header.arglen = sizeof(*ascii) + bufSize; 1536 *resp = rp; 1537 break; 1538 } 1539 1540 case NGM_ASCII2BINARY: 1541 { 1542 int bufSize = 2000; /* XXX hard coded constant */ 1543 const struct ng_cmdlist *c; 1544 const struct ng_parse_type *argstype; 1545 struct ng_mesg *rp, *ascii, *binary; 1546 int off = 0; 1547 1548 /* Data area must contain at least a struct ng_mesg + '\0' */ 1549 ascii = (struct ng_mesg *)msg->data; 1550 if (msg->header.arglen < sizeof(*ascii) + 1 1551 || ascii->header.arglen < 1 1552 || msg->header.arglen 1553 < sizeof(*ascii) + ascii->header.arglen) { 1554 error = EINVAL; 1555 break; 1556 } 1557 ascii->data[ascii->header.arglen - 1] = '\0'; 1558 1559 /* Get a response message with lots of room */ 1560 NG_MKRESPONSE(rp, msg, sizeof(*binary) + bufSize, M_NOWAIT); 1561 if (rp == NULL) { 1562 error = ENOMEM; 1563 break; 1564 } 1565 binary = (struct ng_mesg *)rp->data; 1566 1567 /* Copy ASCII message header to response message payload */ 1568 bcopy(ascii, binary, sizeof(*ascii)); 1569 1570 /* Find command by matching ASCII command string */ 1571 for (c = here->type->cmdlist; 1572 c != NULL && c->name != NULL; c++) { 1573 if (strcmp(ascii->header.cmdstr, c->name) == 0) 1574 break; 1575 } 1576 if (c == NULL || c->name == NULL) { 1577 for (c = ng_generic_cmds; c->name != NULL; c++) { 1578 if (strcmp(ascii->header.cmdstr, c->name) == 0) 1579 break; 1580 } 1581 if (c->name == NULL) { 1582 FREE(rp, M_NETGRAPH); 1583 error = ENOSYS; 1584 break; 1585 } 1586 } 1587 1588 /* Convert command name to binary */ 1589 binary->header.cmd = c->cmd; 1590 binary->header.typecookie = c->cookie; 1591 1592 /* Convert command arguments to binary */ 1593 argstype = (binary->header.flags & NGF_RESP) ? 1594 c->respType : c->mesgType; 1595 if (argstype == NULL) 1596 bufSize = 0; 1597 else { 1598 if ((error = ng_parse(argstype, ascii->data, 1599 &off, (u_char *)binary->data, &bufSize)) != 0) { 1600 FREE(rp, M_NETGRAPH); 1601 break; 1602 } 1603 } 1604 1605 /* Return the result */ 1606 binary->header.arglen = bufSize; 1607 rp->header.arglen = sizeof(*binary) + bufSize; 1608 *resp = rp; 1609 break; 1610 } 1611 1612 case NGM_TEXT_CONFIG: 1613 case NGM_TEXT_STATUS: 1614 /* 1615 * This one is tricky as it passes the command down to the 1616 * actual node, even though it is a generic type command. 1617 * This means we must assume that the msg is already freed 1618 * when control passes back to us. 1619 */ 1620 if (resp == NULL) { 1621 error = EINVAL; 1622 break; 1623 } 1624 if (here->type->rcvmsg != NULL) 1625 return((*here->type->rcvmsg)(here, msg, retaddr, resp)); 1626 /* Fall through if rcvmsg not supported */ 1627 default: 1628 TRAP_ERROR; 1629 error = EINVAL; 1630 } 1631 FREE(msg, M_NETGRAPH); 1632 return (error); 1633 } 1634 1635 /* 1636 * Send a data packet to a node. If the recipient has no 1637 * 'receive data' method, then silently discard the packet. 1638 */ 1639 int 1640 ng_send_data(hook_p hook, struct mbuf *m, meta_p meta) 1641 { 1642 int (*rcvdata)(hook_p, struct mbuf *, meta_p); 1643 int error; 1644 1645 CHECK_DATA_MBUF(m); 1646 if (hook && (hook->flags & HK_INVALID) == 0) { 1647 rcvdata = hook->peer->node->type->rcvdata; 1648 if (rcvdata != NULL) 1649 error = (*rcvdata)(hook->peer, m, meta); 1650 else { 1651 error = 0; 1652 NG_FREE_DATA(m, meta); 1653 } 1654 } else { 1655 TRAP_ERROR; 1656 error = ENOTCONN; 1657 NG_FREE_DATA(m, meta); 1658 } 1659 return (error); 1660 } 1661 1662 /* 1663 * Send a queued data packet to a node. If the recipient has no 1664 * 'receive queued data' method, then try the 'receive data' method above. 1665 */ 1666 int 1667 ng_send_dataq(hook_p hook, struct mbuf *m, meta_p meta) 1668 { 1669 int (*rcvdataq)(hook_p, struct mbuf *, meta_p); 1670 int error; 1671 1672 CHECK_DATA_MBUF(m); 1673 if (hook && (hook->flags & HK_INVALID) == 0) { 1674 rcvdataq = hook->peer->node->type->rcvdataq; 1675 if (rcvdataq != NULL) 1676 error = (*rcvdataq)(hook->peer, m, meta); 1677 else { 1678 error = ng_send_data(hook, m, meta); 1679 } 1680 } else { 1681 TRAP_ERROR; 1682 error = ENOTCONN; 1683 NG_FREE_DATA(m, meta); 1684 } 1685 return (error); 1686 } 1687 1688 /* 1689 * Copy a 'meta'. 1690 * 1691 * Returns new meta, or NULL if original meta is NULL or ENOMEM. 1692 */ 1693 meta_p 1694 ng_copy_meta(meta_p meta) 1695 { 1696 meta_p meta2; 1697 1698 if (meta == NULL) 1699 return (NULL); 1700 MALLOC(meta2, meta_p, meta->used_len, M_NETGRAPH, M_NOWAIT); 1701 if (meta2 == NULL) 1702 return (NULL); 1703 meta2->allocated_len = meta->used_len; 1704 bcopy(meta, meta2, meta->used_len); 1705 return (meta2); 1706 } 1707 1708 /************************************************************************ 1709 Module routines 1710 ************************************************************************/ 1711 1712 /* 1713 * Handle the loading/unloading of a netgraph node type module 1714 */ 1715 int 1716 ng_mod_event(module_t mod, int event, void *data) 1717 { 1718 struct ng_type *const type = data; 1719 int s, error = 0; 1720 1721 switch (event) { 1722 case MOD_LOAD: 1723 1724 /* Register new netgraph node type */ 1725 s = splnet(); 1726 if ((error = ng_newtype(type)) != 0) { 1727 splx(s); 1728 break; 1729 } 1730 1731 /* Call type specific code */ 1732 if (type->mod_event != NULL) 1733 if ((error = (*type->mod_event)(mod, event, data))) { 1734 type->refs--; /* undo it */ 1735 LIST_REMOVE(type, types); 1736 } 1737 splx(s); 1738 break; 1739 1740 case MOD_UNLOAD: 1741 s = splnet(); 1742 if (type->refs > 1) { /* make sure no nodes exist! */ 1743 error = EBUSY; 1744 } else { 1745 if (type->refs == 0) { 1746 /* failed load, nothing to undo */ 1747 splx(s); 1748 break; 1749 } 1750 if (type->mod_event != NULL) { /* check with type */ 1751 error = (*type->mod_event)(mod, event, data); 1752 if (error != 0) { /* type refuses.. */ 1753 splx(s); 1754 break; 1755 } 1756 } 1757 LIST_REMOVE(type, types); 1758 } 1759 splx(s); 1760 break; 1761 1762 default: 1763 if (type->mod_event != NULL) 1764 error = (*type->mod_event)(mod, event, data); 1765 else 1766 error = 0; /* XXX ? */ 1767 break; 1768 } 1769 return (error); 1770 } 1771 1772 /* 1773 * Handle loading and unloading for this code. 1774 * The only thing we need to link into is the NETISR strucure. 1775 */ 1776 static int 1777 ngb_mod_event(module_t mod, int event, void *data) 1778 { 1779 int s, error = 0; 1780 1781 switch (event) { 1782 case MOD_LOAD: 1783 /* Register line discipline */ 1784 s = splimp(); 1785 error = register_netisr(NETISR_NETGRAPH, ngintr); 1786 splx(s); 1787 break; 1788 case MOD_UNLOAD: 1789 /* You cant unload it because an interface may be using it. */ 1790 error = EBUSY; 1791 break; 1792 default: 1793 error = EOPNOTSUPP; 1794 break; 1795 } 1796 return (error); 1797 } 1798 1799 static moduledata_t netgraph_mod = { 1800 "netgraph", 1801 ngb_mod_event, 1802 (NULL) 1803 }; 1804 DECLARE_MODULE(netgraph, netgraph_mod, SI_SUB_DRIVERS, SI_ORDER_MIDDLE); 1805 SYSCTL_NODE(_net, OID_AUTO, graph, CTLFLAG_RW, 0, "netgraph Family"); 1806 SYSCTL_INT(_net_graph, OID_AUTO, abi_version, CTLFLAG_RD, 0, NG_ABI_VERSION,""); 1807 SYSCTL_INT(_net_graph, OID_AUTO, msg_version, CTLFLAG_RD, 0, NG_VERSION, ""); 1808 1809 /************************************************************************ 1810 Queueing routines 1811 ************************************************************************/ 1812 1813 /* The structure for queueing across ISR switches */ 1814 struct ng_queue_entry { 1815 u_long flags; 1816 struct ng_queue_entry *next; 1817 union { 1818 struct { 1819 hook_p da_hook; /* target hook */ 1820 struct mbuf *da_m; 1821 meta_p da_meta; 1822 } data; 1823 struct { 1824 struct ng_mesg *msg_msg; 1825 node_p msg_node; 1826 void *msg_retaddr; 1827 } msg; 1828 } body; 1829 }; 1830 #define NGQF_DATA 0x01 /* the queue element is data */ 1831 #define NGQF_MESG 0x02 /* the queue element is a message */ 1832 1833 static struct ng_queue_entry *ngqbase; /* items to be unqueued */ 1834 static struct ng_queue_entry *ngqlast; /* last item queued */ 1835 static const int ngqroom = 256; /* max items to queue */ 1836 static int ngqsize; /* number of items in queue */ 1837 1838 static struct ng_queue_entry *ngqfree; /* free ones */ 1839 static const int ngqfreemax = 256;/* cache at most this many */ 1840 static int ngqfreesize; /* number of cached entries */ 1841 1842 /* 1843 * Get a queue entry 1844 */ 1845 static struct ng_queue_entry * 1846 ng_getqblk(void) 1847 { 1848 register struct ng_queue_entry *q; 1849 int s; 1850 1851 /* Could be guarding against tty ints or whatever */ 1852 s = splhigh(); 1853 1854 /* Try get a cached queue block, or else allocate a new one */ 1855 if ((q = ngqfree) == NULL) { 1856 splx(s); 1857 if (ngqsize < ngqroom) { /* don't worry about races */ 1858 MALLOC(q, struct ng_queue_entry *, 1859 sizeof(*q), M_NETGRAPH, M_NOWAIT); 1860 } 1861 } else { 1862 ngqfree = q->next; 1863 ngqfreesize--; 1864 splx(s); 1865 } 1866 return (q); 1867 } 1868 1869 /* 1870 * Release a queue entry 1871 */ 1872 #define RETURN_QBLK(q) \ 1873 do { \ 1874 int s; \ 1875 if (ngqfreesize < ngqfreemax) { /* don't worry about races */ \ 1876 s = splhigh(); \ 1877 (q)->next = ngqfree; \ 1878 ngqfree = (q); \ 1879 ngqfreesize++; \ 1880 splx(s); \ 1881 } else { \ 1882 FREE((q), M_NETGRAPH); \ 1883 } \ 1884 } while (0) 1885 1886 /* 1887 * Running at a raised (but we don't know which) processor priority level, 1888 * put the data onto a queue to be picked up by another PPL (probably splnet) 1889 */ 1890 int 1891 ng_queue_data(hook_p hook, struct mbuf *m, meta_p meta) 1892 { 1893 struct ng_queue_entry *q; 1894 int s; 1895 1896 if (hook == NULL) { 1897 NG_FREE_DATA(m, meta); 1898 return (0); 1899 } 1900 if ((q = ng_getqblk()) == NULL) { 1901 NG_FREE_DATA(m, meta); 1902 return (ENOBUFS); 1903 } 1904 1905 /* Fill out the contents */ 1906 q->flags = NGQF_DATA; 1907 q->next = NULL; 1908 q->body.data.da_hook = hook; 1909 q->body.data.da_m = m; 1910 q->body.data.da_meta = meta; 1911 s = splhigh(); /* protect refs and queue */ 1912 hook->refs++; /* don't let it go away while on the queue */ 1913 1914 /* Put it on the queue */ 1915 if (ngqbase) { 1916 ngqlast->next = q; 1917 } else { 1918 ngqbase = q; 1919 } 1920 ngqlast = q; 1921 ngqsize++; 1922 splx(s); 1923 1924 /* Schedule software interrupt to handle it later */ 1925 schednetisr(NETISR_NETGRAPH); 1926 return (0); 1927 } 1928 1929 /* 1930 * Running at a raised (but we don't know which) processor priority level, 1931 * put the msg onto a queue to be picked up by another PPL (probably splnet) 1932 */ 1933 int 1934 ng_queue_msg(node_p here, struct ng_mesg *msg, const char *address) 1935 { 1936 register struct ng_queue_entry *q; 1937 int s; 1938 node_p dest = NULL; 1939 char *retaddr = NULL; 1940 int error; 1941 1942 /* Find the target node. */ 1943 error = ng_path2node(here, address, &dest, &retaddr); 1944 if (error) { 1945 FREE(msg, M_NETGRAPH); 1946 return (error); 1947 } 1948 if ((q = ng_getqblk()) == NULL) { 1949 FREE(msg, M_NETGRAPH); 1950 if (retaddr) 1951 FREE(retaddr, M_NETGRAPH); 1952 return (ENOBUFS); 1953 } 1954 1955 /* Fill out the contents */ 1956 q->flags = NGQF_MESG; 1957 q->next = NULL; 1958 q->body.msg.msg_node = dest; 1959 q->body.msg.msg_msg = msg; 1960 q->body.msg.msg_retaddr = retaddr; 1961 s = splhigh(); /* protect refs and queue */ 1962 dest->refs++; /* don't let it go away while on the queue */ 1963 1964 /* Put it on the queue */ 1965 if (ngqbase) { 1966 ngqlast->next = q; 1967 } else { 1968 ngqbase = q; 1969 } 1970 ngqlast = q; 1971 ngqsize++; 1972 splx(s); 1973 1974 /* Schedule software interrupt to handle it later */ 1975 schednetisr(NETISR_NETGRAPH); 1976 return (0); 1977 } 1978 1979 /* 1980 * Pick an item off the queue, process it, and dispose of the queue entry. 1981 * Should be running at splnet. 1982 */ 1983 static void 1984 ngintr(void) 1985 { 1986 hook_p hook; 1987 struct ng_queue_entry *ngq; 1988 struct mbuf *m; 1989 meta_p meta; 1990 void *retaddr; 1991 struct ng_mesg *msg; 1992 node_p node; 1993 int error = 0; 1994 int s; 1995 1996 while (1) { 1997 s = splhigh(); 1998 if ((ngq = ngqbase)) { 1999 ngqbase = ngq->next; 2000 ngqsize--; 2001 } 2002 splx(s); 2003 if (ngq == NULL) 2004 return; 2005 switch (ngq->flags) { 2006 case NGQF_DATA: 2007 hook = ngq->body.data.da_hook; 2008 m = ngq->body.data.da_m; 2009 meta = ngq->body.data.da_meta; 2010 RETURN_QBLK(ngq); 2011 NG_SEND_DATAQ(error, hook, m, meta); 2012 ng_unref_hook(hook); 2013 break; 2014 case NGQF_MESG: 2015 node = ngq->body.msg.msg_node; 2016 msg = ngq->body.msg.msg_msg; 2017 retaddr = ngq->body.msg.msg_retaddr; 2018 RETURN_QBLK(ngq); 2019 if (node->flags & NG_INVALID) { 2020 FREE(msg, M_NETGRAPH); 2021 } else { 2022 CALL_MSG_HANDLER(error, node, msg, 2023 retaddr, NULL); 2024 } 2025 ng_unref(node); 2026 if (retaddr) 2027 FREE(retaddr, M_NETGRAPH); 2028 break; 2029 default: 2030 RETURN_QBLK(ngq); 2031 } 2032 } 2033 } 2034 2035 2036