ng_base.c revision 178039
1/* 2 * ng_base.c 3 */ 4 5/*- 6 * Copyright (c) 1996-1999 Whistle Communications, Inc. 7 * All rights reserved. 8 * 9 * Subject to the following obligations and disclaimer of warranty, use and 10 * redistribution of this software, in source or object code forms, with or 11 * without modifications are expressly permitted by Whistle Communications; 12 * provided, however, that: 13 * 1. Any and all reproductions of the source or object code must include the 14 * copyright notice above and the following disclaimer of warranties; and 15 * 2. No rights are granted, in any manner or form, to use Whistle 16 * Communications, Inc. trademarks, including the mark "WHISTLE 17 * COMMUNICATIONS" on advertising, endorsements, or otherwise except as 18 * such appears in the above copyright notice or in the software. 19 * 20 * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND 21 * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO 22 * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE, 23 * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF 24 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT. 25 * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY 26 * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS 27 * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE. 28 * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES 29 * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING 30 * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, 31 * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR 32 * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY 33 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 34 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 35 * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY 36 * OF SUCH DAMAGE. 37 * 38 * Authors: Julian Elischer <julian@freebsd.org> 39 * Archie Cobbs <archie@freebsd.org> 40 * 41 * $FreeBSD: head/sys/netgraph/ng_base.c 178039 2008-04-09 19:03:19Z mav $ 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/ctype.h> 52#include <sys/errno.h> 53#include <sys/kdb.h> 54#include <sys/kernel.h> 55#include <sys/ktr.h> 56#include <sys/limits.h> 57#include <sys/malloc.h> 58#include <sys/mbuf.h> 59#include <sys/queue.h> 60#include <sys/sysctl.h> 61#include <sys/syslog.h> 62#include <sys/refcount.h> 63#include <sys/proc.h> 64#include <machine/cpu.h> 65 66#include <net/netisr.h> 67 68#include <netgraph/ng_message.h> 69#include <netgraph/netgraph.h> 70#include <netgraph/ng_parse.h> 71 72MODULE_VERSION(netgraph, NG_ABI_VERSION); 73 74/* Mutex to protect topology events. */ 75static struct mtx ng_topo_mtx; 76 77#ifdef NETGRAPH_DEBUG 78static struct mtx ng_nodelist_mtx; /* protects global node/hook lists */ 79static struct mtx ngq_mtx; /* protects the queue item list */ 80 81static SLIST_HEAD(, ng_node) ng_allnodes; 82static LIST_HEAD(, ng_node) ng_freenodes; /* in debug, we never free() them */ 83static SLIST_HEAD(, ng_hook) ng_allhooks; 84static LIST_HEAD(, ng_hook) ng_freehooks; /* in debug, we never free() them */ 85 86static void ng_dumpitems(void); 87static void ng_dumpnodes(void); 88static void ng_dumphooks(void); 89 90#endif /* NETGRAPH_DEBUG */ 91/* 92 * DEAD versions of the structures. 93 * In order to avoid races, it is sometimes neccesary to point 94 * at SOMETHING even though theoretically, the current entity is 95 * INVALID. Use these to avoid these races. 96 */ 97struct ng_type ng_deadtype = { 98 NG_ABI_VERSION, 99 "dead", 100 NULL, /* modevent */ 101 NULL, /* constructor */ 102 NULL, /* rcvmsg */ 103 NULL, /* shutdown */ 104 NULL, /* newhook */ 105 NULL, /* findhook */ 106 NULL, /* connect */ 107 NULL, /* rcvdata */ 108 NULL, /* disconnect */ 109 NULL, /* cmdlist */ 110}; 111 112struct ng_node ng_deadnode = { 113 "dead", 114 &ng_deadtype, 115 NGF_INVALID, 116 1, /* refs */ 117 0, /* numhooks */ 118 NULL, /* private */ 119 0, /* ID */ 120 LIST_HEAD_INITIALIZER(ng_deadnode.hooks), 121 {}, /* all_nodes list entry */ 122 {}, /* id hashtable list entry */ 123 {}, /* workqueue entry */ 124 { 0, 125 {}, /* should never use! (should hang) */ 126 NULL, 127 &ng_deadnode.nd_input_queue.queue, 128 &ng_deadnode 129 }, 130#ifdef NETGRAPH_DEBUG 131 ND_MAGIC, 132 __FILE__, 133 __LINE__, 134 {NULL} 135#endif /* NETGRAPH_DEBUG */ 136}; 137 138struct ng_hook ng_deadhook = { 139 "dead", 140 NULL, /* private */ 141 HK_INVALID | HK_DEAD, 142 1, /* refs always >= 1 */ 143 0, /* undefined data link type */ 144 &ng_deadhook, /* Peer is self */ 145 &ng_deadnode, /* attached to deadnode */ 146 {}, /* hooks list */ 147 NULL, /* override rcvmsg() */ 148 NULL, /* override rcvdata() */ 149#ifdef NETGRAPH_DEBUG 150 HK_MAGIC, 151 __FILE__, 152 __LINE__, 153 {NULL} 154#endif /* NETGRAPH_DEBUG */ 155}; 156 157/* 158 * END DEAD STRUCTURES 159 */ 160/* List nodes with unallocated work */ 161static TAILQ_HEAD(, ng_node) ng_worklist = TAILQ_HEAD_INITIALIZER(ng_worklist); 162static struct mtx ng_worklist_mtx; /* MUST LOCK NODE FIRST */ 163 164/* List of installed types */ 165static LIST_HEAD(, ng_type) ng_typelist; 166static struct mtx ng_typelist_mtx; 167 168/* Hash related definitions */ 169/* XXX Don't need to initialise them because it's a LIST */ 170#define NG_ID_HASH_SIZE 128 /* most systems wont need even this many */ 171static LIST_HEAD(, ng_node) ng_ID_hash[NG_ID_HASH_SIZE]; 172static struct mtx ng_idhash_mtx; 173/* Method to find a node.. used twice so do it here */ 174#define NG_IDHASH_FN(ID) ((ID) % (NG_ID_HASH_SIZE)) 175#define NG_IDHASH_FIND(ID, node) \ 176 do { \ 177 mtx_assert(&ng_idhash_mtx, MA_OWNED); \ 178 LIST_FOREACH(node, &ng_ID_hash[NG_IDHASH_FN(ID)], \ 179 nd_idnodes) { \ 180 if (NG_NODE_IS_VALID(node) \ 181 && (NG_NODE_ID(node) == ID)) { \ 182 break; \ 183 } \ 184 } \ 185 } while (0) 186 187#define NG_NAME_HASH_SIZE 128 /* most systems wont need even this many */ 188static LIST_HEAD(, ng_node) ng_name_hash[NG_NAME_HASH_SIZE]; 189static struct mtx ng_namehash_mtx; 190#define NG_NAMEHASH(NAME, HASH) \ 191 do { \ 192 u_char h = 0; \ 193 const u_char *c; \ 194 for (c = (const u_char*)(NAME); *c; c++)\ 195 h += *c; \ 196 (HASH) = h % (NG_NAME_HASH_SIZE); \ 197 } while (0) 198 199 200/* Internal functions */ 201static int ng_add_hook(node_p node, const char *name, hook_p * hookp); 202static int ng_generic_msg(node_p here, item_p item, hook_p lasthook); 203static ng_ID_t ng_decodeidname(const char *name); 204static int ngb_mod_event(module_t mod, int event, void *data); 205static void ng_worklist_add(node_p node); 206static void ngintr(void); 207static int ng_apply_item(node_p node, item_p item, int rw); 208static void ng_flush_input_queue(struct ng_queue * ngq); 209static node_p ng_ID2noderef(ng_ID_t ID); 210static int ng_con_nodes(item_p item, node_p node, const char *name, 211 node_p node2, const char *name2); 212static int ng_con_part2(node_p node, item_p item, hook_p hook); 213static int ng_con_part3(node_p node, item_p item, hook_p hook); 214static int ng_mkpeer(node_p node, const char *name, 215 const char *name2, char *type); 216 217/* Imported, these used to be externally visible, some may go back. */ 218void ng_destroy_hook(hook_p hook); 219node_p ng_name2noderef(node_p node, const char *name); 220int ng_path2noderef(node_p here, const char *path, 221 node_p *dest, hook_p *lasthook); 222int ng_make_node(const char *type, node_p *nodepp); 223int ng_path_parse(char *addr, char **node, char **path, char **hook); 224void ng_rmnode(node_p node, hook_p dummy1, void *dummy2, int dummy3); 225void ng_unname(node_p node); 226 227 228/* Our own netgraph malloc type */ 229MALLOC_DEFINE(M_NETGRAPH, "netgraph", "netgraph structures and ctrl messages"); 230MALLOC_DEFINE(M_NETGRAPH_HOOK, "netgraph_hook", "netgraph hook structures"); 231MALLOC_DEFINE(M_NETGRAPH_NODE, "netgraph_node", "netgraph node structures"); 232MALLOC_DEFINE(M_NETGRAPH_ITEM, "netgraph_item", "netgraph item structures"); 233MALLOC_DEFINE(M_NETGRAPH_MSG, "netgraph_msg", "netgraph name storage"); 234 235/* Should not be visible outside this file */ 236 237#define _NG_ALLOC_HOOK(hook) \ 238 MALLOC(hook, hook_p, sizeof(*hook), M_NETGRAPH_HOOK, M_NOWAIT | M_ZERO) 239#define _NG_ALLOC_NODE(node) \ 240 MALLOC(node, node_p, sizeof(*node), M_NETGRAPH_NODE, M_NOWAIT | M_ZERO) 241 242#define NG_QUEUE_LOCK_INIT(n) \ 243 mtx_init(&(n)->q_mtx, "ng_node", NULL, MTX_DEF) 244#define NG_QUEUE_LOCK(n) \ 245 mtx_lock(&(n)->q_mtx) 246#define NG_QUEUE_UNLOCK(n) \ 247 mtx_unlock(&(n)->q_mtx) 248#define NG_WORKLIST_LOCK_INIT() \ 249 mtx_init(&ng_worklist_mtx, "ng_worklist", NULL, MTX_DEF) 250#define NG_WORKLIST_LOCK() \ 251 mtx_lock(&ng_worklist_mtx) 252#define NG_WORKLIST_UNLOCK() \ 253 mtx_unlock(&ng_worklist_mtx) 254 255#ifdef NETGRAPH_DEBUG /*----------------------------------------------*/ 256/* 257 * In debug mode: 258 * In an attempt to help track reference count screwups 259 * we do not free objects back to the malloc system, but keep them 260 * in a local cache where we can examine them and keep information safely 261 * after they have been freed. 262 * We use this scheme for nodes and hooks, and to some extent for items. 263 */ 264static __inline hook_p 265ng_alloc_hook(void) 266{ 267 hook_p hook; 268 SLIST_ENTRY(ng_hook) temp; 269 mtx_lock(&ng_nodelist_mtx); 270 hook = LIST_FIRST(&ng_freehooks); 271 if (hook) { 272 LIST_REMOVE(hook, hk_hooks); 273 bcopy(&hook->hk_all, &temp, sizeof(temp)); 274 bzero(hook, sizeof(struct ng_hook)); 275 bcopy(&temp, &hook->hk_all, sizeof(temp)); 276 mtx_unlock(&ng_nodelist_mtx); 277 hook->hk_magic = HK_MAGIC; 278 } else { 279 mtx_unlock(&ng_nodelist_mtx); 280 _NG_ALLOC_HOOK(hook); 281 if (hook) { 282 hook->hk_magic = HK_MAGIC; 283 mtx_lock(&ng_nodelist_mtx); 284 SLIST_INSERT_HEAD(&ng_allhooks, hook, hk_all); 285 mtx_unlock(&ng_nodelist_mtx); 286 } 287 } 288 return (hook); 289} 290 291static __inline node_p 292ng_alloc_node(void) 293{ 294 node_p node; 295 SLIST_ENTRY(ng_node) temp; 296 mtx_lock(&ng_nodelist_mtx); 297 node = LIST_FIRST(&ng_freenodes); 298 if (node) { 299 LIST_REMOVE(node, nd_nodes); 300 bcopy(&node->nd_all, &temp, sizeof(temp)); 301 bzero(node, sizeof(struct ng_node)); 302 bcopy(&temp, &node->nd_all, sizeof(temp)); 303 mtx_unlock(&ng_nodelist_mtx); 304 node->nd_magic = ND_MAGIC; 305 } else { 306 mtx_unlock(&ng_nodelist_mtx); 307 _NG_ALLOC_NODE(node); 308 if (node) { 309 node->nd_magic = ND_MAGIC; 310 mtx_lock(&ng_nodelist_mtx); 311 SLIST_INSERT_HEAD(&ng_allnodes, node, nd_all); 312 mtx_unlock(&ng_nodelist_mtx); 313 } 314 } 315 return (node); 316} 317 318#define NG_ALLOC_HOOK(hook) do { (hook) = ng_alloc_hook(); } while (0) 319#define NG_ALLOC_NODE(node) do { (node) = ng_alloc_node(); } while (0) 320 321 322#define NG_FREE_HOOK(hook) \ 323 do { \ 324 mtx_lock(&ng_nodelist_mtx); \ 325 LIST_INSERT_HEAD(&ng_freehooks, hook, hk_hooks); \ 326 hook->hk_magic = 0; \ 327 mtx_unlock(&ng_nodelist_mtx); \ 328 } while (0) 329 330#define NG_FREE_NODE(node) \ 331 do { \ 332 mtx_lock(&ng_nodelist_mtx); \ 333 LIST_INSERT_HEAD(&ng_freenodes, node, nd_nodes); \ 334 node->nd_magic = 0; \ 335 mtx_unlock(&ng_nodelist_mtx); \ 336 } while (0) 337 338#else /* NETGRAPH_DEBUG */ /*----------------------------------------------*/ 339 340#define NG_ALLOC_HOOK(hook) _NG_ALLOC_HOOK(hook) 341#define NG_ALLOC_NODE(node) _NG_ALLOC_NODE(node) 342 343#define NG_FREE_HOOK(hook) do { FREE((hook), M_NETGRAPH_HOOK); } while (0) 344#define NG_FREE_NODE(node) do { FREE((node), M_NETGRAPH_NODE); } while (0) 345 346#endif /* NETGRAPH_DEBUG */ /*----------------------------------------------*/ 347 348/* Set this to kdb_enter("X") to catch all errors as they occur */ 349#ifndef TRAP_ERROR 350#define TRAP_ERROR() 351#endif 352 353static ng_ID_t nextID = 1; 354 355#ifdef INVARIANTS 356#define CHECK_DATA_MBUF(m) do { \ 357 struct mbuf *n; \ 358 int total; \ 359 \ 360 M_ASSERTPKTHDR(m); \ 361 for (total = 0, n = (m); n != NULL; n = n->m_next) { \ 362 total += n->m_len; \ 363 if (n->m_nextpkt != NULL) \ 364 panic("%s: m_nextpkt", __func__); \ 365 } \ 366 \ 367 if ((m)->m_pkthdr.len != total) { \ 368 panic("%s: %d != %d", \ 369 __func__, (m)->m_pkthdr.len, total); \ 370 } \ 371 } while (0) 372#else 373#define CHECK_DATA_MBUF(m) 374#endif 375 376#define ERROUT(x) do { error = (x); goto done; } while (0) 377 378/************************************************************************ 379 Parse type definitions for generic messages 380************************************************************************/ 381 382/* Handy structure parse type defining macro */ 383#define DEFINE_PARSE_STRUCT_TYPE(lo, up, args) \ 384static const struct ng_parse_struct_field \ 385 ng_ ## lo ## _type_fields[] = NG_GENERIC_ ## up ## _INFO args; \ 386static const struct ng_parse_type ng_generic_ ## lo ## _type = { \ 387 &ng_parse_struct_type, \ 388 &ng_ ## lo ## _type_fields \ 389} 390 391DEFINE_PARSE_STRUCT_TYPE(mkpeer, MKPEER, ()); 392DEFINE_PARSE_STRUCT_TYPE(connect, CONNECT, ()); 393DEFINE_PARSE_STRUCT_TYPE(name, NAME, ()); 394DEFINE_PARSE_STRUCT_TYPE(rmhook, RMHOOK, ()); 395DEFINE_PARSE_STRUCT_TYPE(nodeinfo, NODEINFO, ()); 396DEFINE_PARSE_STRUCT_TYPE(typeinfo, TYPEINFO, ()); 397DEFINE_PARSE_STRUCT_TYPE(linkinfo, LINKINFO, (&ng_generic_nodeinfo_type)); 398 399/* Get length of an array when the length is stored as a 32 bit 400 value immediately preceding the array -- as with struct namelist 401 and struct typelist. */ 402static int 403ng_generic_list_getLength(const struct ng_parse_type *type, 404 const u_char *start, const u_char *buf) 405{ 406 return *((const u_int32_t *)(buf - 4)); 407} 408 409/* Get length of the array of struct linkinfo inside a struct hooklist */ 410static int 411ng_generic_linkinfo_getLength(const struct ng_parse_type *type, 412 const u_char *start, const u_char *buf) 413{ 414 const struct hooklist *hl = (const struct hooklist *)start; 415 416 return hl->nodeinfo.hooks; 417} 418 419/* Array type for a variable length array of struct namelist */ 420static const struct ng_parse_array_info ng_nodeinfoarray_type_info = { 421 &ng_generic_nodeinfo_type, 422 &ng_generic_list_getLength 423}; 424static const struct ng_parse_type ng_generic_nodeinfoarray_type = { 425 &ng_parse_array_type, 426 &ng_nodeinfoarray_type_info 427}; 428 429/* Array type for a variable length array of struct typelist */ 430static const struct ng_parse_array_info ng_typeinfoarray_type_info = { 431 &ng_generic_typeinfo_type, 432 &ng_generic_list_getLength 433}; 434static const struct ng_parse_type ng_generic_typeinfoarray_type = { 435 &ng_parse_array_type, 436 &ng_typeinfoarray_type_info 437}; 438 439/* Array type for array of struct linkinfo in struct hooklist */ 440static const struct ng_parse_array_info ng_generic_linkinfo_array_type_info = { 441 &ng_generic_linkinfo_type, 442 &ng_generic_linkinfo_getLength 443}; 444static const struct ng_parse_type ng_generic_linkinfo_array_type = { 445 &ng_parse_array_type, 446 &ng_generic_linkinfo_array_type_info 447}; 448 449DEFINE_PARSE_STRUCT_TYPE(typelist, TYPELIST, (&ng_generic_nodeinfoarray_type)); 450DEFINE_PARSE_STRUCT_TYPE(hooklist, HOOKLIST, 451 (&ng_generic_nodeinfo_type, &ng_generic_linkinfo_array_type)); 452DEFINE_PARSE_STRUCT_TYPE(listnodes, LISTNODES, 453 (&ng_generic_nodeinfoarray_type)); 454 455/* List of commands and how to convert arguments to/from ASCII */ 456static const struct ng_cmdlist ng_generic_cmds[] = { 457 { 458 NGM_GENERIC_COOKIE, 459 NGM_SHUTDOWN, 460 "shutdown", 461 NULL, 462 NULL 463 }, 464 { 465 NGM_GENERIC_COOKIE, 466 NGM_MKPEER, 467 "mkpeer", 468 &ng_generic_mkpeer_type, 469 NULL 470 }, 471 { 472 NGM_GENERIC_COOKIE, 473 NGM_CONNECT, 474 "connect", 475 &ng_generic_connect_type, 476 NULL 477 }, 478 { 479 NGM_GENERIC_COOKIE, 480 NGM_NAME, 481 "name", 482 &ng_generic_name_type, 483 NULL 484 }, 485 { 486 NGM_GENERIC_COOKIE, 487 NGM_RMHOOK, 488 "rmhook", 489 &ng_generic_rmhook_type, 490 NULL 491 }, 492 { 493 NGM_GENERIC_COOKIE, 494 NGM_NODEINFO, 495 "nodeinfo", 496 NULL, 497 &ng_generic_nodeinfo_type 498 }, 499 { 500 NGM_GENERIC_COOKIE, 501 NGM_LISTHOOKS, 502 "listhooks", 503 NULL, 504 &ng_generic_hooklist_type 505 }, 506 { 507 NGM_GENERIC_COOKIE, 508 NGM_LISTNAMES, 509 "listnames", 510 NULL, 511 &ng_generic_listnodes_type /* same as NGM_LISTNODES */ 512 }, 513 { 514 NGM_GENERIC_COOKIE, 515 NGM_LISTNODES, 516 "listnodes", 517 NULL, 518 &ng_generic_listnodes_type 519 }, 520 { 521 NGM_GENERIC_COOKIE, 522 NGM_LISTTYPES, 523 "listtypes", 524 NULL, 525 &ng_generic_typeinfo_type 526 }, 527 { 528 NGM_GENERIC_COOKIE, 529 NGM_TEXT_CONFIG, 530 "textconfig", 531 NULL, 532 &ng_parse_string_type 533 }, 534 { 535 NGM_GENERIC_COOKIE, 536 NGM_TEXT_STATUS, 537 "textstatus", 538 NULL, 539 &ng_parse_string_type 540 }, 541 { 542 NGM_GENERIC_COOKIE, 543 NGM_ASCII2BINARY, 544 "ascii2binary", 545 &ng_parse_ng_mesg_type, 546 &ng_parse_ng_mesg_type 547 }, 548 { 549 NGM_GENERIC_COOKIE, 550 NGM_BINARY2ASCII, 551 "binary2ascii", 552 &ng_parse_ng_mesg_type, 553 &ng_parse_ng_mesg_type 554 }, 555 { 0 } 556}; 557 558/************************************************************************ 559 Node routines 560************************************************************************/ 561 562/* 563 * Instantiate a node of the requested type 564 */ 565int 566ng_make_node(const char *typename, node_p *nodepp) 567{ 568 struct ng_type *type; 569 int error; 570 571 /* Check that the type makes sense */ 572 if (typename == NULL) { 573 TRAP_ERROR(); 574 return (EINVAL); 575 } 576 577 /* Locate the node type. If we fail we return. Do not try to load 578 * module. 579 */ 580 if ((type = ng_findtype(typename)) == NULL) 581 return (ENXIO); 582 583 /* 584 * If we have a constructor, then make the node and 585 * call the constructor to do type specific initialisation. 586 */ 587 if (type->constructor != NULL) { 588 if ((error = ng_make_node_common(type, nodepp)) == 0) { 589 if ((error = ((*type->constructor)(*nodepp)) != 0)) { 590 NG_NODE_UNREF(*nodepp); 591 } 592 } 593 } else { 594 /* 595 * Node has no constructor. We cannot ask for one 596 * to be made. It must be brought into existence by 597 * some external agency. The external agency should 598 * call ng_make_node_common() directly to get the 599 * netgraph part initialised. 600 */ 601 TRAP_ERROR(); 602 error = EINVAL; 603 } 604 return (error); 605} 606 607/* 608 * Generic node creation. Called by node initialisation for externally 609 * instantiated nodes (e.g. hardware, sockets, etc ). 610 * The returned node has a reference count of 1. 611 */ 612int 613ng_make_node_common(struct ng_type *type, node_p *nodepp) 614{ 615 node_p node; 616 617 /* Require the node type to have been already installed */ 618 if (ng_findtype(type->name) == NULL) { 619 TRAP_ERROR(); 620 return (EINVAL); 621 } 622 623 /* Make a node and try attach it to the type */ 624 NG_ALLOC_NODE(node); 625 if (node == NULL) { 626 TRAP_ERROR(); 627 return (ENOMEM); 628 } 629 node->nd_type = type; 630 NG_NODE_REF(node); /* note reference */ 631 type->refs++; 632 633 NG_QUEUE_LOCK_INIT(&node->nd_input_queue); 634 node->nd_input_queue.queue = NULL; 635 node->nd_input_queue.last = &node->nd_input_queue.queue; 636 node->nd_input_queue.q_flags = 0; 637 node->nd_input_queue.q_node = node; 638 639 /* Initialize hook list for new node */ 640 LIST_INIT(&node->nd_hooks); 641 642 /* Link us into the name hash. */ 643 mtx_lock(&ng_namehash_mtx); 644 LIST_INSERT_HEAD(&ng_name_hash[0], node, nd_nodes); 645 mtx_unlock(&ng_namehash_mtx); 646 647 /* get an ID and put us in the hash chain */ 648 mtx_lock(&ng_idhash_mtx); 649 for (;;) { /* wrap protection, even if silly */ 650 node_p node2 = NULL; 651 node->nd_ID = nextID++; /* 137/second for 1 year before wrap */ 652 653 /* Is there a problem with the new number? */ 654 NG_IDHASH_FIND(node->nd_ID, node2); /* already taken? */ 655 if ((node->nd_ID != 0) && (node2 == NULL)) { 656 break; 657 } 658 } 659 LIST_INSERT_HEAD(&ng_ID_hash[NG_IDHASH_FN(node->nd_ID)], 660 node, nd_idnodes); 661 mtx_unlock(&ng_idhash_mtx); 662 663 /* Done */ 664 *nodepp = node; 665 return (0); 666} 667 668/* 669 * Forceably start the shutdown process on a node. Either call 670 * its shutdown method, or do the default shutdown if there is 671 * no type-specific method. 672 * 673 * We can only be called from a shutdown message, so we know we have 674 * a writer lock, and therefore exclusive access. It also means 675 * that we should not be on the work queue, but we check anyhow. 676 * 677 * Persistent node types must have a type-specific method which 678 * allocates a new node in which case, this one is irretrievably going away, 679 * or cleans up anything it needs, and just makes the node valid again, 680 * in which case we allow the node to survive. 681 * 682 * XXX We need to think of how to tell a persistent node that we 683 * REALLY need to go away because the hardware has gone or we 684 * are rebooting.... etc. 685 */ 686void 687ng_rmnode(node_p node, hook_p dummy1, void *dummy2, int dummy3) 688{ 689 hook_p hook; 690 691 /* Check if it's already shutting down */ 692 if ((node->nd_flags & NGF_CLOSING) != 0) 693 return; 694 695 if (node == &ng_deadnode) { 696 printf ("shutdown called on deadnode\n"); 697 return; 698 } 699 700 /* Add an extra reference so it doesn't go away during this */ 701 NG_NODE_REF(node); 702 703 /* 704 * Mark it invalid so any newcomers know not to try use it 705 * Also add our own mark so we can't recurse 706 * note that NGF_INVALID does not do this as it's also set during 707 * creation 708 */ 709 node->nd_flags |= NGF_INVALID|NGF_CLOSING; 710 711 /* If node has its pre-shutdown method, then call it first*/ 712 if (node->nd_type && node->nd_type->close) 713 (*node->nd_type->close)(node); 714 715 /* Notify all remaining connected nodes to disconnect */ 716 while ((hook = LIST_FIRST(&node->nd_hooks)) != NULL) 717 ng_destroy_hook(hook); 718 719 /* 720 * Drain the input queue forceably. 721 * it has no hooks so what's it going to do, bleed on someone? 722 * Theoretically we came here from a queue entry that was added 723 * Just before the queue was closed, so it should be empty anyway. 724 * Also removes us from worklist if needed. 725 */ 726 ng_flush_input_queue(&node->nd_input_queue); 727 728 /* Ask the type if it has anything to do in this case */ 729 if (node->nd_type && node->nd_type->shutdown) { 730 (*node->nd_type->shutdown)(node); 731 if (NG_NODE_IS_VALID(node)) { 732 /* 733 * Well, blow me down if the node code hasn't declared 734 * that it doesn't want to die. 735 * Presumably it is a persistant node. 736 * If we REALLY want it to go away, 737 * e.g. hardware going away, 738 * Our caller should set NGF_REALLY_DIE in nd_flags. 739 */ 740 node->nd_flags &= ~(NGF_INVALID|NGF_CLOSING); 741 NG_NODE_UNREF(node); /* Assume they still have theirs */ 742 return; 743 } 744 } else { /* do the default thing */ 745 NG_NODE_UNREF(node); 746 } 747 748 ng_unname(node); /* basically a NOP these days */ 749 750 /* 751 * Remove extra reference, possibly the last 752 * Possible other holders of references may include 753 * timeout callouts, but theoretically the node's supposed to 754 * have cancelled them. Possibly hardware dependencies may 755 * force a driver to 'linger' with a reference. 756 */ 757 NG_NODE_UNREF(node); 758} 759 760/* 761 * Remove a reference to the node, possibly the last. 762 * deadnode always acts as it it were the last. 763 */ 764int 765ng_unref_node(node_p node) 766{ 767 int v; 768 769 if (node == &ng_deadnode) { 770 return (0); 771 } 772 773 v = atomic_fetchadd_int(&node->nd_refs, -1); 774 775 if (v == 1) { /* we were the last */ 776 777 mtx_lock(&ng_namehash_mtx); 778 node->nd_type->refs--; /* XXX maybe should get types lock? */ 779 LIST_REMOVE(node, nd_nodes); 780 mtx_unlock(&ng_namehash_mtx); 781 782 mtx_lock(&ng_idhash_mtx); 783 LIST_REMOVE(node, nd_idnodes); 784 mtx_unlock(&ng_idhash_mtx); 785 786 mtx_destroy(&node->nd_input_queue.q_mtx); 787 NG_FREE_NODE(node); 788 } 789 return (v - 1); 790} 791 792/************************************************************************ 793 Node ID handling 794************************************************************************/ 795static node_p 796ng_ID2noderef(ng_ID_t ID) 797{ 798 node_p node; 799 mtx_lock(&ng_idhash_mtx); 800 NG_IDHASH_FIND(ID, node); 801 if(node) 802 NG_NODE_REF(node); 803 mtx_unlock(&ng_idhash_mtx); 804 return(node); 805} 806 807ng_ID_t 808ng_node2ID(node_p node) 809{ 810 return (node ? NG_NODE_ID(node) : 0); 811} 812 813/************************************************************************ 814 Node name handling 815************************************************************************/ 816 817/* 818 * Assign a node a name. Once assigned, the name cannot be changed. 819 */ 820int 821ng_name_node(node_p node, const char *name) 822{ 823 int i, hash; 824 node_p node2; 825 826 /* Check the name is valid */ 827 for (i = 0; i < NG_NODESIZ; i++) { 828 if (name[i] == '\0' || name[i] == '.' || name[i] == ':') 829 break; 830 } 831 if (i == 0 || name[i] != '\0') { 832 TRAP_ERROR(); 833 return (EINVAL); 834 } 835 if (ng_decodeidname(name) != 0) { /* valid IDs not allowed here */ 836 TRAP_ERROR(); 837 return (EINVAL); 838 } 839 840 /* Check the name isn't already being used */ 841 if ((node2 = ng_name2noderef(node, name)) != NULL) { 842 NG_NODE_UNREF(node2); 843 TRAP_ERROR(); 844 return (EADDRINUSE); 845 } 846 847 /* copy it */ 848 strlcpy(NG_NODE_NAME(node), name, NG_NODESIZ); 849 850 /* Update name hash. */ 851 NG_NAMEHASH(name, hash); 852 mtx_lock(&ng_namehash_mtx); 853 LIST_REMOVE(node, nd_nodes); 854 LIST_INSERT_HEAD(&ng_name_hash[hash], node, nd_nodes); 855 mtx_unlock(&ng_namehash_mtx); 856 857 return (0); 858} 859 860/* 861 * Find a node by absolute name. The name should NOT end with ':' 862 * The name "." means "this node" and "[xxx]" means "the node 863 * with ID (ie, at address) xxx". 864 * 865 * Returns the node if found, else NULL. 866 * Eventually should add something faster than a sequential search. 867 * Note it acquires a reference on the node so you can be sure it's still 868 * there. 869 */ 870node_p 871ng_name2noderef(node_p here, const char *name) 872{ 873 node_p node; 874 ng_ID_t temp; 875 int hash; 876 877 /* "." means "this node" */ 878 if (strcmp(name, ".") == 0) { 879 NG_NODE_REF(here); 880 return(here); 881 } 882 883 /* Check for name-by-ID */ 884 if ((temp = ng_decodeidname(name)) != 0) { 885 return (ng_ID2noderef(temp)); 886 } 887 888 /* Find node by name */ 889 NG_NAMEHASH(name, hash); 890 mtx_lock(&ng_namehash_mtx); 891 LIST_FOREACH(node, &ng_name_hash[hash], nd_nodes) { 892 if (NG_NODE_IS_VALID(node) && 893 (strcmp(NG_NODE_NAME(node), name) == 0)) { 894 break; 895 } 896 } 897 if (node) 898 NG_NODE_REF(node); 899 mtx_unlock(&ng_namehash_mtx); 900 return (node); 901} 902 903/* 904 * Decode an ID name, eg. "[f03034de]". Returns 0 if the 905 * string is not valid, otherwise returns the value. 906 */ 907static ng_ID_t 908ng_decodeidname(const char *name) 909{ 910 const int len = strlen(name); 911 char *eptr; 912 u_long val; 913 914 /* Check for proper length, brackets, no leading junk */ 915 if ((len < 3) 916 || (name[0] != '[') 917 || (name[len - 1] != ']') 918 || (!isxdigit(name[1]))) { 919 return ((ng_ID_t)0); 920 } 921 922 /* Decode number */ 923 val = strtoul(name + 1, &eptr, 16); 924 if ((eptr - name != len - 1) 925 || (val == ULONG_MAX) 926 || (val == 0)) { 927 return ((ng_ID_t)0); 928 } 929 return (ng_ID_t)val; 930} 931 932/* 933 * Remove a name from a node. This should only be called 934 * when shutting down and removing the node. 935 * IF we allow name changing this may be more resurrected. 936 */ 937void 938ng_unname(node_p node) 939{ 940} 941 942/************************************************************************ 943 Hook routines 944 Names are not optional. Hooks are always connected, except for a 945 brief moment within these routines. On invalidation or during creation 946 they are connected to the 'dead' hook. 947************************************************************************/ 948 949/* 950 * Remove a hook reference 951 */ 952void 953ng_unref_hook(hook_p hook) 954{ 955 int v; 956 957 if (hook == &ng_deadhook) { 958 return; 959 } 960 961 v = atomic_fetchadd_int(&hook->hk_refs, -1); 962 963 if (v == 1) { /* we were the last */ 964 if (_NG_HOOK_NODE(hook)) /* it'll probably be ng_deadnode */ 965 _NG_NODE_UNREF((_NG_HOOK_NODE(hook))); 966 NG_FREE_HOOK(hook); 967 } 968} 969 970/* 971 * Add an unconnected hook to a node. Only used internally. 972 * Assumes node is locked. (XXX not yet true ) 973 */ 974static int 975ng_add_hook(node_p node, const char *name, hook_p *hookp) 976{ 977 hook_p hook; 978 int error = 0; 979 980 /* Check that the given name is good */ 981 if (name == NULL) { 982 TRAP_ERROR(); 983 return (EINVAL); 984 } 985 if (ng_findhook(node, name) != NULL) { 986 TRAP_ERROR(); 987 return (EEXIST); 988 } 989 990 /* Allocate the hook and link it up */ 991 NG_ALLOC_HOOK(hook); 992 if (hook == NULL) { 993 TRAP_ERROR(); 994 return (ENOMEM); 995 } 996 hook->hk_refs = 1; /* add a reference for us to return */ 997 hook->hk_flags = HK_INVALID; 998 hook->hk_peer = &ng_deadhook; /* start off this way */ 999 hook->hk_node = node; 1000 NG_NODE_REF(node); /* each hook counts as a reference */ 1001 1002 /* Set hook name */ 1003 strlcpy(NG_HOOK_NAME(hook), name, NG_HOOKSIZ); 1004 1005 /* 1006 * Check if the node type code has something to say about it 1007 * If it fails, the unref of the hook will also unref the node. 1008 */ 1009 if (node->nd_type->newhook != NULL) { 1010 if ((error = (*node->nd_type->newhook)(node, hook, name))) { 1011 NG_HOOK_UNREF(hook); /* this frees the hook */ 1012 return (error); 1013 } 1014 } 1015 /* 1016 * The 'type' agrees so far, so go ahead and link it in. 1017 * We'll ask again later when we actually connect the hooks. 1018 */ 1019 LIST_INSERT_HEAD(&node->nd_hooks, hook, hk_hooks); 1020 node->nd_numhooks++; 1021 NG_HOOK_REF(hook); /* one for the node */ 1022 1023 if (hookp) 1024 *hookp = hook; 1025 return (0); 1026} 1027 1028/* 1029 * Find a hook 1030 * 1031 * Node types may supply their own optimized routines for finding 1032 * hooks. If none is supplied, we just do a linear search. 1033 * XXX Possibly we should add a reference to the hook? 1034 */ 1035hook_p 1036ng_findhook(node_p node, const char *name) 1037{ 1038 hook_p hook; 1039 1040 if (node->nd_type->findhook != NULL) 1041 return (*node->nd_type->findhook)(node, name); 1042 LIST_FOREACH(hook, &node->nd_hooks, hk_hooks) { 1043 if (NG_HOOK_IS_VALID(hook) 1044 && (strcmp(NG_HOOK_NAME(hook), name) == 0)) 1045 return (hook); 1046 } 1047 return (NULL); 1048} 1049 1050/* 1051 * Destroy a hook 1052 * 1053 * As hooks are always attached, this really destroys two hooks. 1054 * The one given, and the one attached to it. Disconnect the hooks 1055 * from each other first. We reconnect the peer hook to the 'dead' 1056 * hook so that it can still exist after we depart. We then 1057 * send the peer its own destroy message. This ensures that we only 1058 * interact with the peer's structures when it is locked processing that 1059 * message. We hold a reference to the peer hook so we are guaranteed that 1060 * the peer hook and node are still going to exist until 1061 * we are finished there as the hook holds a ref on the node. 1062 * We run this same code again on the peer hook, but that time it is already 1063 * attached to the 'dead' hook. 1064 * 1065 * This routine is called at all stages of hook creation 1066 * on error detection and must be able to handle any such stage. 1067 */ 1068void 1069ng_destroy_hook(hook_p hook) 1070{ 1071 hook_p peer; 1072 node_p node; 1073 1074 if (hook == &ng_deadhook) { /* better safe than sorry */ 1075 printf("ng_destroy_hook called on deadhook\n"); 1076 return; 1077 } 1078 1079 /* 1080 * Protect divorce process with mutex, to avoid races on 1081 * simultaneous disconnect. 1082 */ 1083 mtx_lock(&ng_topo_mtx); 1084 1085 hook->hk_flags |= HK_INVALID; 1086 1087 peer = NG_HOOK_PEER(hook); 1088 node = NG_HOOK_NODE(hook); 1089 1090 if (peer && (peer != &ng_deadhook)) { 1091 /* 1092 * Set the peer to point to ng_deadhook 1093 * from this moment on we are effectively independent it. 1094 * send it an rmhook message of it's own. 1095 */ 1096 peer->hk_peer = &ng_deadhook; /* They no longer know us */ 1097 hook->hk_peer = &ng_deadhook; /* Nor us, them */ 1098 if (NG_HOOK_NODE(peer) == &ng_deadnode) { 1099 /* 1100 * If it's already divorced from a node, 1101 * just free it. 1102 */ 1103 mtx_unlock(&ng_topo_mtx); 1104 } else { 1105 mtx_unlock(&ng_topo_mtx); 1106 ng_rmhook_self(peer); /* Send it a surprise */ 1107 } 1108 NG_HOOK_UNREF(peer); /* account for peer link */ 1109 NG_HOOK_UNREF(hook); /* account for peer link */ 1110 } else 1111 mtx_unlock(&ng_topo_mtx); 1112 1113 mtx_assert(&ng_topo_mtx, MA_NOTOWNED); 1114 1115 /* 1116 * Remove the hook from the node's list to avoid possible recursion 1117 * in case the disconnection results in node shutdown. 1118 */ 1119 if (node == &ng_deadnode) { /* happens if called from ng_con_nodes() */ 1120 return; 1121 } 1122 LIST_REMOVE(hook, hk_hooks); 1123 node->nd_numhooks--; 1124 if (node->nd_type->disconnect) { 1125 /* 1126 * The type handler may elect to destroy the node so don't 1127 * trust its existence after this point. (except 1128 * that we still hold a reference on it. (which we 1129 * inherrited from the hook we are destroying) 1130 */ 1131 (*node->nd_type->disconnect) (hook); 1132 } 1133 1134 /* 1135 * Note that because we will point to ng_deadnode, the original node 1136 * is not decremented automatically so we do that manually. 1137 */ 1138 _NG_HOOK_NODE(hook) = &ng_deadnode; 1139 NG_NODE_UNREF(node); /* We no longer point to it so adjust count */ 1140 NG_HOOK_UNREF(hook); /* Account for linkage (in list) to node */ 1141} 1142 1143/* 1144 * Take two hooks on a node and merge the connection so that the given node 1145 * is effectively bypassed. 1146 */ 1147int 1148ng_bypass(hook_p hook1, hook_p hook2) 1149{ 1150 if (hook1->hk_node != hook2->hk_node) { 1151 TRAP_ERROR(); 1152 return (EINVAL); 1153 } 1154 hook1->hk_peer->hk_peer = hook2->hk_peer; 1155 hook2->hk_peer->hk_peer = hook1->hk_peer; 1156 1157 hook1->hk_peer = &ng_deadhook; 1158 hook2->hk_peer = &ng_deadhook; 1159 1160 NG_HOOK_UNREF(hook1); 1161 NG_HOOK_UNREF(hook2); 1162 1163 /* XXX If we ever cache methods on hooks update them as well */ 1164 ng_destroy_hook(hook1); 1165 ng_destroy_hook(hook2); 1166 return (0); 1167} 1168 1169/* 1170 * Install a new netgraph type 1171 */ 1172int 1173ng_newtype(struct ng_type *tp) 1174{ 1175 const size_t namelen = strlen(tp->name); 1176 1177 /* Check version and type name fields */ 1178 if ((tp->version != NG_ABI_VERSION) 1179 || (namelen == 0) 1180 || (namelen >= NG_TYPESIZ)) { 1181 TRAP_ERROR(); 1182 if (tp->version != NG_ABI_VERSION) { 1183 printf("Netgraph: Node type rejected. ABI mismatch. Suggest recompile\n"); 1184 } 1185 return (EINVAL); 1186 } 1187 1188 /* Check for name collision */ 1189 if (ng_findtype(tp->name) != NULL) { 1190 TRAP_ERROR(); 1191 return (EEXIST); 1192 } 1193 1194 1195 /* Link in new type */ 1196 mtx_lock(&ng_typelist_mtx); 1197 LIST_INSERT_HEAD(&ng_typelist, tp, types); 1198 tp->refs = 1; /* first ref is linked list */ 1199 mtx_unlock(&ng_typelist_mtx); 1200 return (0); 1201} 1202 1203/* 1204 * unlink a netgraph type 1205 * If no examples exist 1206 */ 1207int 1208ng_rmtype(struct ng_type *tp) 1209{ 1210 /* Check for name collision */ 1211 if (tp->refs != 1) { 1212 TRAP_ERROR(); 1213 return (EBUSY); 1214 } 1215 1216 /* Unlink type */ 1217 mtx_lock(&ng_typelist_mtx); 1218 LIST_REMOVE(tp, types); 1219 mtx_unlock(&ng_typelist_mtx); 1220 return (0); 1221} 1222 1223/* 1224 * Look for a type of the name given 1225 */ 1226struct ng_type * 1227ng_findtype(const char *typename) 1228{ 1229 struct ng_type *type; 1230 1231 mtx_lock(&ng_typelist_mtx); 1232 LIST_FOREACH(type, &ng_typelist, types) { 1233 if (strcmp(type->name, typename) == 0) 1234 break; 1235 } 1236 mtx_unlock(&ng_typelist_mtx); 1237 return (type); 1238} 1239 1240/************************************************************************ 1241 Composite routines 1242************************************************************************/ 1243/* 1244 * Connect two nodes using the specified hooks, using queued functions. 1245 */ 1246static int 1247ng_con_part3(node_p node, item_p item, hook_p hook) 1248{ 1249 int error = 0; 1250 1251 /* 1252 * When we run, we know that the node 'node' is locked for us. 1253 * Our caller has a reference on the hook. 1254 * Our caller has a reference on the node. 1255 * (In this case our caller is ng_apply_item() ). 1256 * The peer hook has a reference on the hook. 1257 * We are all set up except for the final call to the node, and 1258 * the clearing of the INVALID flag. 1259 */ 1260 if (NG_HOOK_NODE(hook) == &ng_deadnode) { 1261 /* 1262 * The node must have been freed again since we last visited 1263 * here. ng_destry_hook() has this effect but nothing else does. 1264 * We should just release our references and 1265 * free anything we can think of. 1266 * Since we know it's been destroyed, and it's our caller 1267 * that holds the references, just return. 1268 */ 1269 ERROUT(ENOENT); 1270 } 1271 if (hook->hk_node->nd_type->connect) { 1272 if ((error = (*hook->hk_node->nd_type->connect) (hook))) { 1273 ng_destroy_hook(hook); /* also zaps peer */ 1274 printf("failed in ng_con_part3()\n"); 1275 ERROUT(error); 1276 } 1277 } 1278 /* 1279 * XXX this is wrong for SMP. Possibly we need 1280 * to separate out 'create' and 'invalid' flags. 1281 * should only set flags on hooks we have locked under our node. 1282 */ 1283 hook->hk_flags &= ~HK_INVALID; 1284done: 1285 NG_FREE_ITEM(item); 1286 return (error); 1287} 1288 1289static int 1290ng_con_part2(node_p node, item_p item, hook_p hook) 1291{ 1292 hook_p peer; 1293 int error = 0; 1294 1295 /* 1296 * When we run, we know that the node 'node' is locked for us. 1297 * Our caller has a reference on the hook. 1298 * Our caller has a reference on the node. 1299 * (In this case our caller is ng_apply_item() ). 1300 * The peer hook has a reference on the hook. 1301 * our node pointer points to the 'dead' node. 1302 * First check the hook name is unique. 1303 * Should not happen because we checked before queueing this. 1304 */ 1305 if (ng_findhook(node, NG_HOOK_NAME(hook)) != NULL) { 1306 TRAP_ERROR(); 1307 ng_destroy_hook(hook); /* should destroy peer too */ 1308 printf("failed in ng_con_part2()\n"); 1309 ERROUT(EEXIST); 1310 } 1311 /* 1312 * Check if the node type code has something to say about it 1313 * If it fails, the unref of the hook will also unref the attached node, 1314 * however since that node is 'ng_deadnode' this will do nothing. 1315 * The peer hook will also be destroyed. 1316 */ 1317 if (node->nd_type->newhook != NULL) { 1318 if ((error = (*node->nd_type->newhook)(node, hook, 1319 hook->hk_name))) { 1320 ng_destroy_hook(hook); /* should destroy peer too */ 1321 printf("failed in ng_con_part2()\n"); 1322 ERROUT(error); 1323 } 1324 } 1325 1326 /* 1327 * The 'type' agrees so far, so go ahead and link it in. 1328 * We'll ask again later when we actually connect the hooks. 1329 */ 1330 hook->hk_node = node; /* just overwrite ng_deadnode */ 1331 NG_NODE_REF(node); /* each hook counts as a reference */ 1332 LIST_INSERT_HEAD(&node->nd_hooks, hook, hk_hooks); 1333 node->nd_numhooks++; 1334 NG_HOOK_REF(hook); /* one for the node */ 1335 1336 /* 1337 * We now have a symmetrical situation, where both hooks have been 1338 * linked to their nodes, the newhook methods have been called 1339 * And the references are all correct. The hooks are still marked 1340 * as invalid, as we have not called the 'connect' methods 1341 * yet. 1342 * We can call the local one immediately as we have the 1343 * node locked, but we need to queue the remote one. 1344 */ 1345 if (hook->hk_node->nd_type->connect) { 1346 if ((error = (*hook->hk_node->nd_type->connect) (hook))) { 1347 ng_destroy_hook(hook); /* also zaps peer */ 1348 printf("failed in ng_con_part2(A)\n"); 1349 ERROUT(error); 1350 } 1351 } 1352 1353 /* 1354 * Acquire topo mutex to avoid race with ng_destroy_hook(). 1355 */ 1356 mtx_lock(&ng_topo_mtx); 1357 peer = hook->hk_peer; 1358 if (peer == &ng_deadhook) { 1359 mtx_unlock(&ng_topo_mtx); 1360 printf("failed in ng_con_part2(B)\n"); 1361 ng_destroy_hook(hook); 1362 ERROUT(ENOENT); 1363 } 1364 mtx_unlock(&ng_topo_mtx); 1365 1366 if ((error = ng_send_fn2(peer->hk_node, peer, item, &ng_con_part3, 1367 NULL, 0, NG_REUSE_ITEM))) { 1368 printf("failed in ng_con_part2(C)\n"); 1369 ng_destroy_hook(hook); /* also zaps peer */ 1370 return (error); /* item was consumed. */ 1371 } 1372 hook->hk_flags &= ~HK_INVALID; /* need both to be able to work */ 1373 return (0); /* item was consumed. */ 1374done: 1375 NG_FREE_ITEM(item); 1376 return (error); 1377} 1378 1379/* 1380 * Connect this node with another node. We assume that this node is 1381 * currently locked, as we are only called from an NGM_CONNECT message. 1382 */ 1383static int 1384ng_con_nodes(item_p item, node_p node, const char *name, 1385 node_p node2, const char *name2) 1386{ 1387 int error; 1388 hook_p hook; 1389 hook_p hook2; 1390 1391 if (ng_findhook(node2, name2) != NULL) { 1392 return(EEXIST); 1393 } 1394 if ((error = ng_add_hook(node, name, &hook))) /* gives us a ref */ 1395 return (error); 1396 /* Allocate the other hook and link it up */ 1397 NG_ALLOC_HOOK(hook2); 1398 if (hook2 == NULL) { 1399 TRAP_ERROR(); 1400 ng_destroy_hook(hook); /* XXX check ref counts so far */ 1401 NG_HOOK_UNREF(hook); /* including our ref */ 1402 return (ENOMEM); 1403 } 1404 hook2->hk_refs = 1; /* start with a reference for us. */ 1405 hook2->hk_flags = HK_INVALID; 1406 hook2->hk_peer = hook; /* Link the two together */ 1407 hook->hk_peer = hook2; 1408 NG_HOOK_REF(hook); /* Add a ref for the peer to each*/ 1409 NG_HOOK_REF(hook2); 1410 hook2->hk_node = &ng_deadnode; 1411 strlcpy(NG_HOOK_NAME(hook2), name2, NG_HOOKSIZ); 1412 1413 /* 1414 * Queue the function above. 1415 * Procesing continues in that function in the lock context of 1416 * the other node. 1417 */ 1418 if ((error = ng_send_fn2(node2, hook2, item, &ng_con_part2, NULL, 0, 1419 NG_NOFLAGS))) { 1420 printf("failed in ng_con_nodes(): %d\n", error); 1421 ng_destroy_hook(hook); /* also zaps peer */ 1422 } 1423 1424 NG_HOOK_UNREF(hook); /* Let each hook go if it wants to */ 1425 NG_HOOK_UNREF(hook2); 1426 return (error); 1427} 1428 1429/* 1430 * Make a peer and connect. 1431 * We assume that the local node is locked. 1432 * The new node probably doesn't need a lock until 1433 * it has a hook, because it cannot really have any work until then, 1434 * but we should think about it a bit more. 1435 * 1436 * The problem may come if the other node also fires up 1437 * some hardware or a timer or some other source of activation, 1438 * also it may already get a command msg via it's ID. 1439 * 1440 * We could use the same method as ng_con_nodes() but we'd have 1441 * to add ability to remove the node when failing. (Not hard, just 1442 * make arg1 point to the node to remove). 1443 * Unless of course we just ignore failure to connect and leave 1444 * an unconnected node? 1445 */ 1446static int 1447ng_mkpeer(node_p node, const char *name, const char *name2, char *type) 1448{ 1449 node_p node2; 1450 hook_p hook1, hook2; 1451 int error; 1452 1453 if ((error = ng_make_node(type, &node2))) { 1454 return (error); 1455 } 1456 1457 if ((error = ng_add_hook(node, name, &hook1))) { /* gives us a ref */ 1458 ng_rmnode(node2, NULL, NULL, 0); 1459 return (error); 1460 } 1461 1462 if ((error = ng_add_hook(node2, name2, &hook2))) { 1463 ng_rmnode(node2, NULL, NULL, 0); 1464 ng_destroy_hook(hook1); 1465 NG_HOOK_UNREF(hook1); 1466 return (error); 1467 } 1468 1469 /* 1470 * Actually link the two hooks together. 1471 */ 1472 hook1->hk_peer = hook2; 1473 hook2->hk_peer = hook1; 1474 1475 /* Each hook is referenced by the other */ 1476 NG_HOOK_REF(hook1); 1477 NG_HOOK_REF(hook2); 1478 1479 /* Give each node the opportunity to veto the pending connection */ 1480 if (hook1->hk_node->nd_type->connect) { 1481 error = (*hook1->hk_node->nd_type->connect) (hook1); 1482 } 1483 1484 if ((error == 0) && hook2->hk_node->nd_type->connect) { 1485 error = (*hook2->hk_node->nd_type->connect) (hook2); 1486 1487 } 1488 1489 /* 1490 * drop the references we were holding on the two hooks. 1491 */ 1492 if (error) { 1493 ng_destroy_hook(hook2); /* also zaps hook1 */ 1494 ng_rmnode(node2, NULL, NULL, 0); 1495 } else { 1496 /* As a last act, allow the hooks to be used */ 1497 hook1->hk_flags &= ~HK_INVALID; 1498 hook2->hk_flags &= ~HK_INVALID; 1499 } 1500 NG_HOOK_UNREF(hook1); 1501 NG_HOOK_UNREF(hook2); 1502 return (error); 1503} 1504 1505/************************************************************************ 1506 Utility routines to send self messages 1507************************************************************************/ 1508 1509/* Shut this node down as soon as everyone is clear of it */ 1510/* Should add arg "immediately" to jump the queue */ 1511int 1512ng_rmnode_self(node_p node) 1513{ 1514 int error; 1515 1516 if (node == &ng_deadnode) 1517 return (0); 1518 node->nd_flags |= NGF_INVALID; 1519 if (node->nd_flags & NGF_CLOSING) 1520 return (0); 1521 1522 error = ng_send_fn(node, NULL, &ng_rmnode, NULL, 0); 1523 return (error); 1524} 1525 1526static void 1527ng_rmhook_part2(node_p node, hook_p hook, void *arg1, int arg2) 1528{ 1529 ng_destroy_hook(hook); 1530 return ; 1531} 1532 1533int 1534ng_rmhook_self(hook_p hook) 1535{ 1536 int error; 1537 node_p node = NG_HOOK_NODE(hook); 1538 1539 if (node == &ng_deadnode) 1540 return (0); 1541 1542 error = ng_send_fn(node, hook, &ng_rmhook_part2, NULL, 0); 1543 return (error); 1544} 1545 1546/*********************************************************************** 1547 * Parse and verify a string of the form: <NODE:><PATH> 1548 * 1549 * Such a string can refer to a specific node or a specific hook 1550 * on a specific node, depending on how you look at it. In the 1551 * latter case, the PATH component must not end in a dot. 1552 * 1553 * Both <NODE:> and <PATH> are optional. The <PATH> is a string 1554 * of hook names separated by dots. This breaks out the original 1555 * string, setting *nodep to "NODE" (or NULL if none) and *pathp 1556 * to "PATH" (or NULL if degenerate). Also, *hookp will point to 1557 * the final hook component of <PATH>, if any, otherwise NULL. 1558 * 1559 * This returns -1 if the path is malformed. The char ** are optional. 1560 ***********************************************************************/ 1561int 1562ng_path_parse(char *addr, char **nodep, char **pathp, char **hookp) 1563{ 1564 char *node, *path, *hook; 1565 int k; 1566 1567 /* 1568 * Extract absolute NODE, if any 1569 */ 1570 for (path = addr; *path && *path != ':'; path++); 1571 if (*path) { 1572 node = addr; /* Here's the NODE */ 1573 *path++ = '\0'; /* Here's the PATH */ 1574 1575 /* Node name must not be empty */ 1576 if (!*node) 1577 return -1; 1578 1579 /* A name of "." is OK; otherwise '.' not allowed */ 1580 if (strcmp(node, ".") != 0) { 1581 for (k = 0; node[k]; k++) 1582 if (node[k] == '.') 1583 return -1; 1584 } 1585 } else { 1586 node = NULL; /* No absolute NODE */ 1587 path = addr; /* Here's the PATH */ 1588 } 1589 1590 /* Snoop for illegal characters in PATH */ 1591 for (k = 0; path[k]; k++) 1592 if (path[k] == ':') 1593 return -1; 1594 1595 /* Check for no repeated dots in PATH */ 1596 for (k = 0; path[k]; k++) 1597 if (path[k] == '.' && path[k + 1] == '.') 1598 return -1; 1599 1600 /* Remove extra (degenerate) dots from beginning or end of PATH */ 1601 if (path[0] == '.') 1602 path++; 1603 if (*path && path[strlen(path) - 1] == '.') 1604 path[strlen(path) - 1] = 0; 1605 1606 /* If PATH has a dot, then we're not talking about a hook */ 1607 if (*path) { 1608 for (hook = path, k = 0; path[k]; k++) 1609 if (path[k] == '.') { 1610 hook = NULL; 1611 break; 1612 } 1613 } else 1614 path = hook = NULL; 1615 1616 /* Done */ 1617 if (nodep) 1618 *nodep = node; 1619 if (pathp) 1620 *pathp = path; 1621 if (hookp) 1622 *hookp = hook; 1623 return (0); 1624} 1625 1626/* 1627 * Given a path, which may be absolute or relative, and a starting node, 1628 * return the destination node. 1629 */ 1630int 1631ng_path2noderef(node_p here, const char *address, 1632 node_p *destp, hook_p *lasthook) 1633{ 1634 char fullpath[NG_PATHSIZ]; 1635 char *nodename, *path, pbuf[2]; 1636 node_p node, oldnode; 1637 char *cp; 1638 hook_p hook = NULL; 1639 1640 /* Initialize */ 1641 if (destp == NULL) { 1642 TRAP_ERROR(); 1643 return EINVAL; 1644 } 1645 *destp = NULL; 1646 1647 /* Make a writable copy of address for ng_path_parse() */ 1648 strncpy(fullpath, address, sizeof(fullpath) - 1); 1649 fullpath[sizeof(fullpath) - 1] = '\0'; 1650 1651 /* Parse out node and sequence of hooks */ 1652 if (ng_path_parse(fullpath, &nodename, &path, NULL) < 0) { 1653 TRAP_ERROR(); 1654 return EINVAL; 1655 } 1656 if (path == NULL) { 1657 pbuf[0] = '.'; /* Needs to be writable */ 1658 pbuf[1] = '\0'; 1659 path = pbuf; 1660 } 1661 1662 /* 1663 * For an absolute address, jump to the starting node. 1664 * Note that this holds a reference on the node for us. 1665 * Don't forget to drop the reference if we don't need it. 1666 */ 1667 if (nodename) { 1668 node = ng_name2noderef(here, nodename); 1669 if (node == NULL) { 1670 TRAP_ERROR(); 1671 return (ENOENT); 1672 } 1673 } else { 1674 if (here == NULL) { 1675 TRAP_ERROR(); 1676 return (EINVAL); 1677 } 1678 node = here; 1679 NG_NODE_REF(node); 1680 } 1681 1682 /* 1683 * Now follow the sequence of hooks 1684 * XXX 1685 * We actually cannot guarantee that the sequence 1686 * is not being demolished as we crawl along it 1687 * without extra-ordinary locking etc. 1688 * So this is a bit dodgy to say the least. 1689 * We can probably hold up some things by holding 1690 * the nodelist mutex for the time of this 1691 * crawl if we wanted.. At least that way we wouldn't have to 1692 * worry about the nodes disappearing, but the hooks would still 1693 * be a problem. 1694 */ 1695 for (cp = path; node != NULL && *cp != '\0'; ) { 1696 char *segment; 1697 1698 /* 1699 * Break out the next path segment. Replace the dot we just 1700 * found with a NUL; "cp" points to the next segment (or the 1701 * NUL at the end). 1702 */ 1703 for (segment = cp; *cp != '\0'; cp++) { 1704 if (*cp == '.') { 1705 *cp++ = '\0'; 1706 break; 1707 } 1708 } 1709 1710 /* Empty segment */ 1711 if (*segment == '\0') 1712 continue; 1713 1714 /* We have a segment, so look for a hook by that name */ 1715 hook = ng_findhook(node, segment); 1716 1717 /* Can't get there from here... */ 1718 if (hook == NULL 1719 || NG_HOOK_PEER(hook) == NULL 1720 || NG_HOOK_NOT_VALID(hook) 1721 || NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook))) { 1722 TRAP_ERROR(); 1723 NG_NODE_UNREF(node); 1724#if 0 1725 printf("hooknotvalid %s %s %d %d %d %d ", 1726 path, 1727 segment, 1728 hook == NULL, 1729 NG_HOOK_PEER(hook) == NULL, 1730 NG_HOOK_NOT_VALID(hook), 1731 NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook))); 1732#endif 1733 return (ENOENT); 1734 } 1735 1736 /* 1737 * Hop on over to the next node 1738 * XXX 1739 * Big race conditions here as hooks and nodes go away 1740 * *** Idea.. store an ng_ID_t in each hook and use that 1741 * instead of the direct hook in this crawl? 1742 */ 1743 oldnode = node; 1744 if ((node = NG_PEER_NODE(hook))) 1745 NG_NODE_REF(node); /* XXX RACE */ 1746 NG_NODE_UNREF(oldnode); /* XXX another race */ 1747 if (NG_NODE_NOT_VALID(node)) { 1748 NG_NODE_UNREF(node); /* XXX more races */ 1749 node = NULL; 1750 } 1751 } 1752 1753 /* If node somehow missing, fail here (probably this is not needed) */ 1754 if (node == NULL) { 1755 TRAP_ERROR(); 1756 return (ENXIO); 1757 } 1758 1759 /* Done */ 1760 *destp = node; 1761 if (lasthook != NULL) 1762 *lasthook = (hook ? NG_HOOK_PEER(hook) : NULL); 1763 return (0); 1764} 1765 1766/***************************************************************\ 1767* Input queue handling. 1768* All activities are submitted to the node via the input queue 1769* which implements a multiple-reader/single-writer gate. 1770* Items which cannot be handled immediately are queued. 1771* 1772* read-write queue locking inline functions * 1773\***************************************************************/ 1774 1775static __inline item_p ng_dequeue(struct ng_queue * ngq, int *rw); 1776static __inline item_p ng_acquire_read(struct ng_queue * ngq, 1777 item_p item); 1778static __inline item_p ng_acquire_write(struct ng_queue * ngq, 1779 item_p item); 1780static __inline void ng_leave_read(struct ng_queue * ngq); 1781static __inline void ng_leave_write(struct ng_queue * ngq); 1782static __inline void ng_queue_rw(struct ng_queue * ngq, 1783 item_p item, int rw); 1784 1785/* 1786 * Definition of the bits fields in the ng_queue flag word. 1787 * Defined here rather than in netgraph.h because no-one should fiddle 1788 * with them. 1789 * 1790 * The ordering here may be important! don't shuffle these. 1791 */ 1792/*- 1793 Safety Barrier--------+ (adjustable to suit taste) (not used yet) 1794 | 1795 V 1796+-------+-------+-------+-------+-------+-------+-------+-------+ 1797 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 1798 | |A|c|t|i|v|e| |R|e|a|d|e|r| |C|o|u|n|t| | | | | | | | | |P|A| 1799 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |O|W| 1800+-------+-------+-------+-------+-------+-------+-------+-------+ 1801 \___________________________ ____________________________/ | | 1802 V | | 1803 [active reader count] | | 1804 | | 1805 Operation Pending -------------------------------+ | 1806 | 1807 Active Writer ---------------------------------------+ 1808 1809Node queue has such semantics: 1810- All flags modifications are atomic. 1811- Reader count can be incremented only if there is no writer or pending flags. 1812 As soon as this can't be done with single operation, it is implemented with 1813 spin loop and atomic_cmpset(). 1814- Writer flag can be set only if there is no any bits set. 1815 It is implemented with atomic_cmpset(). 1816- Pending flag can be set any time, but to avoid collision on queue processing 1817 all queue fields are protected by the mutex. 1818- Queue processing thread reads queue holding the mutex, but releases it while 1819 processing. When queue is empty pending flag is removed. 1820*/ 1821 1822#define WRITER_ACTIVE 0x00000001 1823#define OP_PENDING 0x00000002 1824#define READER_INCREMENT 0x00000004 1825#define READER_MASK 0xfffffffc /* Not valid if WRITER_ACTIVE is set */ 1826#define SAFETY_BARRIER 0x00100000 /* 128K items queued should be enough */ 1827 1828/* Defines of more elaborate states on the queue */ 1829/* Mask of bits a new read cares about */ 1830#define NGQ_RMASK (WRITER_ACTIVE|OP_PENDING) 1831 1832/* Mask of bits a new write cares about */ 1833#define NGQ_WMASK (NGQ_RMASK|READER_MASK) 1834 1835/* Test to decide if there is something on the queue. */ 1836#define QUEUE_ACTIVE(QP) ((QP)->q_flags & OP_PENDING) 1837 1838/* How to decide what the next queued item is. */ 1839#define HEAD_IS_READER(QP) NGI_QUEUED_READER((QP)->queue) 1840#define HEAD_IS_WRITER(QP) NGI_QUEUED_WRITER((QP)->queue) /* notused */ 1841 1842/* Read the status to decide if the next item on the queue can now run. */ 1843#define QUEUED_READER_CAN_PROCEED(QP) \ 1844 (((QP)->q_flags & (NGQ_RMASK & ~OP_PENDING)) == 0) 1845#define QUEUED_WRITER_CAN_PROCEED(QP) \ 1846 (((QP)->q_flags & (NGQ_WMASK & ~OP_PENDING)) == 0) 1847 1848/* Is there a chance of getting ANY work off the queue? */ 1849#define NEXT_QUEUED_ITEM_CAN_PROCEED(QP) \ 1850 ((HEAD_IS_READER(QP)) ? QUEUED_READER_CAN_PROCEED(QP) : \ 1851 QUEUED_WRITER_CAN_PROCEED(QP)) 1852 1853 1854#define NGQRW_R 0 1855#define NGQRW_W 1 1856 1857/* 1858 * Taking into account the current state of the queue and node, possibly take 1859 * the next entry off the queue and return it. Return NULL if there was 1860 * nothing we could return, either because there really was nothing there, or 1861 * because the node was in a state where it cannot yet process the next item 1862 * on the queue. 1863 */ 1864static __inline item_p 1865ng_dequeue(struct ng_queue *ngq, int *rw) 1866{ 1867 item_p item; 1868 1869 /* This MUST be called with the mutex held. */ 1870 mtx_assert(&ngq->q_mtx, MA_OWNED); 1871 1872 /* If there is nothing queued, then just return. */ 1873 if (!QUEUE_ACTIVE(ngq)) { 1874 CTR4(KTR_NET, "%20s: node [%x] (%p) queue empty; " 1875 "queue flags 0x%lx", __func__, 1876 ngq->q_node->nd_ID, ngq->q_node, ngq->q_flags); 1877 return (NULL); 1878 } 1879 1880 /* 1881 * From here, we can assume there is a head item. 1882 * We need to find out what it is and if it can be dequeued, given 1883 * the current state of the node. 1884 */ 1885 if (HEAD_IS_READER(ngq)) { 1886 while (1) { 1887 long t = ngq->q_flags; 1888 if (t & WRITER_ACTIVE) { 1889 /* There is writer, reader can't proceed. */ 1890 CTR4(KTR_NET, "%20s: node [%x] (%p) queued reader " 1891 "can't proceed; queue flags 0x%lx", __func__, 1892 ngq->q_node->nd_ID, ngq->q_node, t); 1893 return (NULL); 1894 } 1895 if (atomic_cmpset_acq_long(&ngq->q_flags, t, 1896 t + READER_INCREMENT)) 1897 break; 1898 cpu_spinwait(); 1899 } 1900 /* We have got reader lock for the node. */ 1901 *rw = NGQRW_R; 1902 } else if (atomic_cmpset_acq_long(&ngq->q_flags, OP_PENDING, 1903 OP_PENDING + WRITER_ACTIVE)) { 1904 /* We have got writer lock for the node. */ 1905 *rw = NGQRW_W; 1906 } else { 1907 /* There is somebody other, writer can't proceed. */ 1908 CTR4(KTR_NET, "%20s: node [%x] (%p) queued writer " 1909 "can't proceed; queue flags 0x%lx", __func__, 1910 ngq->q_node->nd_ID, ngq->q_node, ngq->q_flags); 1911 return (NULL); 1912 } 1913 1914 /* 1915 * Now we dequeue the request (whatever it may be) and correct the 1916 * pending flags and the next and last pointers. 1917 */ 1918 item = ngq->queue; 1919 ngq->queue = item->el_next; 1920 if (ngq->last == &(item->el_next)) { 1921 ngq->last = &(ngq->queue); 1922 atomic_clear_long(&ngq->q_flags, OP_PENDING); 1923 } 1924 CTR6(KTR_NET, "%20s: node [%x] (%p) returning item %p as %s; " 1925 "queue flags 0x%lx", __func__, 1926 ngq->q_node->nd_ID, ngq->q_node, item, *rw ? "WRITER" : "READER" , 1927 ngq->q_flags); 1928 return (item); 1929} 1930 1931/* 1932 * Queue a packet to be picked up later by someone else. 1933 * If the queue could be run now, add node to the queue handler's worklist. 1934 */ 1935static __inline void 1936ng_queue_rw(struct ng_queue * ngq, item_p item, int rw) 1937{ 1938 if (rw == NGQRW_W) 1939 NGI_SET_WRITER(item); 1940 else 1941 NGI_SET_READER(item); 1942 item->el_next = NULL; /* maybe not needed */ 1943 1944 NG_QUEUE_LOCK(ngq); 1945 /* Set OP_PENDING flag and enqueue the item. */ 1946 atomic_set_long(&ngq->q_flags, OP_PENDING); 1947 *ngq->last = item; 1948 ngq->last = &(item->el_next); 1949 1950 CTR5(KTR_NET, "%20s: node [%x] (%p) queued item %p as %s", __func__, 1951 ngq->q_node->nd_ID, ngq->q_node, item, rw ? "WRITER" : "READER" ); 1952 1953 /* 1954 * We can take the worklist lock with the node locked 1955 * BUT NOT THE REVERSE! 1956 */ 1957 if (NEXT_QUEUED_ITEM_CAN_PROCEED(ngq)) 1958 ng_worklist_add(ngq->q_node); 1959 NG_QUEUE_UNLOCK(ngq); 1960} 1961 1962/* Acquire reader lock on node. If node is busy, queue the packet. */ 1963static __inline item_p 1964ng_acquire_read(struct ng_queue *ngq, item_p item) 1965{ 1966 KASSERT(ngq != &ng_deadnode.nd_input_queue, 1967 ("%s: working on deadnode", __func__)); 1968 1969 /* Reader needs node without writer and pending items. */ 1970 while (1) { 1971 long t = ngq->q_flags; 1972 if (t & NGQ_RMASK) 1973 break; /* Node is not ready for reader. */ 1974 if (atomic_cmpset_acq_long(&ngq->q_flags, t, t + READER_INCREMENT)) { 1975 /* Successfully grabbed node */ 1976 CTR4(KTR_NET, "%20s: node [%x] (%p) acquired item %p", 1977 __func__, ngq->q_node->nd_ID, ngq->q_node, item); 1978 return (item); 1979 } 1980 cpu_spinwait(); 1981 }; 1982 1983 /* Queue the request for later. */ 1984 ng_queue_rw(ngq, item, NGQRW_R); 1985 1986 return (NULL); 1987} 1988 1989/* Acquire writer lock on node. If node is busy, queue the packet. */ 1990static __inline item_p 1991ng_acquire_write(struct ng_queue *ngq, item_p item) 1992{ 1993 KASSERT(ngq != &ng_deadnode.nd_input_queue, 1994 ("%s: working on deadnode", __func__)); 1995 1996 /* Writer needs completely idle node. */ 1997 if (atomic_cmpset_acq_long(&ngq->q_flags, 0, WRITER_ACTIVE)) { 1998 /* Successfully grabbed node */ 1999 CTR4(KTR_NET, "%20s: node [%x] (%p) acquired item %p", 2000 __func__, ngq->q_node->nd_ID, ngq->q_node, item); 2001 return (item); 2002 } 2003 2004 /* Queue the request for later. */ 2005 ng_queue_rw(ngq, item, NGQRW_W); 2006 2007 return (NULL); 2008} 2009 2010#if 0 2011static __inline item_p 2012ng_upgrade_write(struct ng_queue *ngq, item_p item) 2013{ 2014 KASSERT(ngq != &ng_deadnode.nd_input_queue, 2015 ("%s: working on deadnode", __func__)); 2016 2017 NGI_SET_WRITER(item); 2018 2019 mtx_lock_spin(&(ngq->q_mtx)); 2020 2021 /* 2022 * There will never be no readers as we are there ourselves. 2023 * Set the WRITER_ACTIVE flags ASAP to block out fast track readers. 2024 * The caller we are running from will call ng_leave_read() 2025 * soon, so we must account for that. We must leave again with the 2026 * READER lock. If we find other readers, then 2027 * queue the request for later. However "later" may be rignt now 2028 * if there are no readers. We don't really care if there are queued 2029 * items as we will bypass them anyhow. 2030 */ 2031 atomic_add_long(&ngq->q_flags, WRITER_ACTIVE - READER_INCREMENT); 2032 if (ngq->q_flags & (NGQ_WMASK & ~OP_PENDING) == WRITER_ACTIVE) { 2033 mtx_unlock_spin(&(ngq->q_mtx)); 2034 2035 /* It's just us, act on the item. */ 2036 /* will NOT drop writer lock when done */ 2037 ng_apply_item(node, item, 0); 2038 2039 /* 2040 * Having acted on the item, atomically 2041 * down grade back to READER and finish up 2042 */ 2043 atomic_add_long(&ngq->q_flags, 2044 READER_INCREMENT - WRITER_ACTIVE); 2045 2046 /* Our caller will call ng_leave_read() */ 2047 return; 2048 } 2049 /* 2050 * It's not just us active, so queue us AT THE HEAD. 2051 * "Why?" I hear you ask. 2052 * Put us at the head of the queue as we've already been 2053 * through it once. If there is nothing else waiting, 2054 * set the correct flags. 2055 */ 2056 if ((item->el_next = ngq->queue) == NULL) { 2057 /* 2058 * Set up the "last" pointer. 2059 * We are the only (and thus last) item 2060 */ 2061 ngq->last = &(item->el_next); 2062 2063 /* We've gone from, 0 to 1 item in the queue */ 2064 atomic_set_long(&ngq->q_flags, OP_PENDING); 2065 2066 CTR3(KTR_NET, "%20s: node [%x] (%p) set OP_PENDING", __func__, 2067 ngq->q_node->nd_ID, ngq->q_node); 2068 }; 2069 ngq->queue = item; 2070 CTR5(KTR_NET, "%20s: node [%x] (%p) requeued item %p as WRITER", 2071 __func__, ngq->q_node->nd_ID, ngq->q_node, item ); 2072 2073 /* Reverse what we did above. That downgrades us back to reader */ 2074 atomic_add_long(&ngq->q_flags, READER_INCREMENT - WRITER_ACTIVE); 2075 if (QUEUE_ACTIVE(ngq) && NEXT_QUEUED_ITEM_CAN_PROCEED(ngq)) 2076 ng_worklist_add(ngq->q_node); 2077 mtx_unlock_spin(&(ngq->q_mtx)); 2078 2079 return; 2080} 2081 2082#endif 2083 2084/* Release reader lock. */ 2085static __inline void 2086ng_leave_read(struct ng_queue *ngq) 2087{ 2088 atomic_subtract_rel_long(&ngq->q_flags, READER_INCREMENT); 2089} 2090 2091/* Release writer lock. */ 2092static __inline void 2093ng_leave_write(struct ng_queue *ngq) 2094{ 2095 atomic_clear_rel_long(&ngq->q_flags, WRITER_ACTIVE); 2096} 2097 2098/* Purge node queue. Called on node shutdown. */ 2099static void 2100ng_flush_input_queue(struct ng_queue * ngq) 2101{ 2102 item_p item; 2103 2104 NG_QUEUE_LOCK(ngq); 2105 while (ngq->queue) { 2106 item = ngq->queue; 2107 ngq->queue = item->el_next; 2108 if (ngq->last == &(item->el_next)) { 2109 ngq->last = &(ngq->queue); 2110 atomic_clear_long(&ngq->q_flags, OP_PENDING); 2111 } 2112 NG_QUEUE_UNLOCK(ngq); 2113 2114 /* If the item is supplying a callback, call it with an error */ 2115 if (item->apply != NULL) { 2116 if (item->depth == 1) 2117 item->apply->error = ENOENT; 2118 if (refcount_release(&item->apply->refs)) { 2119 (*item->apply->apply)(item->apply->context, 2120 item->apply->error); 2121 } 2122 } 2123 NG_FREE_ITEM(item); 2124 NG_QUEUE_LOCK(ngq); 2125 } 2126 NG_QUEUE_UNLOCK(ngq); 2127} 2128 2129/*********************************************************************** 2130* Externally visible method for sending or queueing messages or data. 2131***********************************************************************/ 2132 2133/* 2134 * The module code should have filled out the item correctly by this stage: 2135 * Common: 2136 * reference to destination node. 2137 * Reference to destination rcv hook if relevant. 2138 * apply pointer must be or NULL or reference valid struct ng_apply_info. 2139 * Data: 2140 * pointer to mbuf 2141 * Control_Message: 2142 * pointer to msg. 2143 * ID of original sender node. (return address) 2144 * Function: 2145 * Function pointer 2146 * void * argument 2147 * integer argument 2148 * 2149 * The nodes have several routines and macros to help with this task: 2150 */ 2151 2152int 2153ng_snd_item(item_p item, int flags) 2154{ 2155 hook_p hook; 2156 node_p node; 2157 int queue, rw; 2158 struct ng_queue *ngq; 2159 int error = 0; 2160 2161 /* We are sending item, so it must be present! */ 2162 KASSERT(item != NULL, ("ng_snd_item: item is NULL")); 2163 2164#ifdef NETGRAPH_DEBUG 2165 _ngi_check(item, __FILE__, __LINE__); 2166#endif 2167 2168 /* Item was sent once more, postpone apply() call. */ 2169 if (item->apply) 2170 refcount_acquire(&item->apply->refs); 2171 2172 node = NGI_NODE(item); 2173 /* Node is never optional. */ 2174 KASSERT(node != NULL, ("ng_snd_item: node is NULL")); 2175 2176 hook = NGI_HOOK(item); 2177 /* Valid hook and mbuf are mandatory for data. */ 2178 if ((item->el_flags & NGQF_TYPE) == NGQF_DATA) { 2179 KASSERT(hook != NULL, ("ng_snd_item: hook for data is NULL")); 2180 if (NGI_M(item) == NULL) 2181 ERROUT(EINVAL); 2182 CHECK_DATA_MBUF(NGI_M(item)); 2183 } 2184 2185 /* 2186 * If the item or the node specifies single threading, force 2187 * writer semantics. Similarly, the node may say one hook always 2188 * produces writers. These are overrides. 2189 */ 2190 if (((item->el_flags & NGQF_RW) == NGQF_WRITER) || 2191 (node->nd_flags & NGF_FORCE_WRITER) || 2192 (hook && (hook->hk_flags & HK_FORCE_WRITER))) { 2193 rw = NGQRW_W; 2194 } else { 2195 rw = NGQRW_R; 2196 } 2197 2198 /* 2199 * If sender or receiver requests queued delivery or stack usage 2200 * level is dangerous - enqueue message. 2201 */ 2202 if ((flags & NG_QUEUE) || (hook && (hook->hk_flags & HK_QUEUE))) { 2203 queue = 1; 2204 } else { 2205 queue = 0; 2206#ifdef GET_STACK_USAGE 2207 /* 2208 * Most of netgraph nodes have small stack consumption and 2209 * for them 25% of free stack space is more than enough. 2210 * Nodes/hooks with higher stack usage should be marked as 2211 * HI_STACK. For them 50% of stack will be guaranteed then. 2212 * XXX: Values 25% and 50% are completely empirical. 2213 */ 2214 size_t st, su, sl; 2215 GET_STACK_USAGE(st, su); 2216 sl = st - su; 2217 if ((sl * 4 < st) || 2218 ((sl * 2 < st) && ((node->nd_flags & NGF_HI_STACK) || 2219 (hook && (hook->hk_flags & HK_HI_STACK))))) { 2220 queue = 1; 2221 } 2222#endif 2223 } 2224 2225 ngq = &node->nd_input_queue; 2226 if (queue) { 2227 item->depth = 1; 2228 /* Put it on the queue for that node*/ 2229 ng_queue_rw(ngq, item, rw); 2230 return ((flags & NG_PROGRESS) ? EINPROGRESS : 0); 2231 } 2232 2233 /* 2234 * We already decided how we will be queueud or treated. 2235 * Try get the appropriate operating permission. 2236 */ 2237 if (rw == NGQRW_R) 2238 item = ng_acquire_read(ngq, item); 2239 else 2240 item = ng_acquire_write(ngq, item); 2241 2242 /* Item was queued while trying to get permission. */ 2243 if (item == NULL) 2244 return ((flags & NG_PROGRESS) ? EINPROGRESS : 0); 2245 2246 NGI_GET_NODE(item, node); /* zaps stored node */ 2247 2248 item->depth++; 2249 error = ng_apply_item(node, item, rw); /* drops r/w lock when done */ 2250 2251 /* If something is waiting on queue and ready, schedule it. */ 2252 if (QUEUE_ACTIVE(ngq)) { 2253 NG_QUEUE_LOCK(ngq); 2254 if (QUEUE_ACTIVE(ngq) && NEXT_QUEUED_ITEM_CAN_PROCEED(ngq)) 2255 ng_worklist_add(ngq->q_node); 2256 NG_QUEUE_UNLOCK(ngq); 2257 } 2258 2259 /* 2260 * Node may go away as soon as we remove the reference. 2261 * Whatever we do, DO NOT access the node again! 2262 */ 2263 NG_NODE_UNREF(node); 2264 2265 return (error); 2266 2267done: 2268 /* If was not sent, apply callback here. */ 2269 if (item->apply != NULL) { 2270 if (item->depth == 0 && error != 0) 2271 item->apply->error = error; 2272 if (refcount_release(&item->apply->refs)) { 2273 (*item->apply->apply)(item->apply->context, 2274 item->apply->error); 2275 } 2276 } 2277 2278 NG_FREE_ITEM(item); 2279 return (error); 2280} 2281 2282/* 2283 * We have an item that was possibly queued somewhere. 2284 * It should contain all the information needed 2285 * to run it on the appropriate node/hook. 2286 * If there is apply pointer and we own the last reference, call apply(). 2287 */ 2288static int 2289ng_apply_item(node_p node, item_p item, int rw) 2290{ 2291 hook_p hook; 2292 ng_rcvdata_t *rcvdata; 2293 ng_rcvmsg_t *rcvmsg; 2294 struct ng_apply_info *apply; 2295 int error = 0, depth; 2296 2297 /* Node and item are never optional. */ 2298 KASSERT(node != NULL, ("ng_apply_item: node is NULL")); 2299 KASSERT(item != NULL, ("ng_apply_item: item is NULL")); 2300 2301 NGI_GET_HOOK(item, hook); /* clears stored hook */ 2302#ifdef NETGRAPH_DEBUG 2303 _ngi_check(item, __FILE__, __LINE__); 2304#endif 2305 2306 apply = item->apply; 2307 depth = item->depth; 2308 2309 switch (item->el_flags & NGQF_TYPE) { 2310 case NGQF_DATA: 2311 /* 2312 * Check things are still ok as when we were queued. 2313 */ 2314 KASSERT(hook != NULL, ("ng_apply_item: hook for data is NULL")); 2315 if (NG_HOOK_NOT_VALID(hook) || 2316 NG_NODE_NOT_VALID(node)) { 2317 error = EIO; 2318 NG_FREE_ITEM(item); 2319 break; 2320 } 2321 /* 2322 * If no receive method, just silently drop it. 2323 * Give preference to the hook over-ride method 2324 */ 2325 if ((!(rcvdata = hook->hk_rcvdata)) 2326 && (!(rcvdata = NG_HOOK_NODE(hook)->nd_type->rcvdata))) { 2327 error = 0; 2328 NG_FREE_ITEM(item); 2329 break; 2330 } 2331 error = (*rcvdata)(hook, item); 2332 break; 2333 case NGQF_MESG: 2334 if (hook && NG_HOOK_NOT_VALID(hook)) { 2335 /* 2336 * The hook has been zapped then we can't use it. 2337 * Immediately drop its reference. 2338 * The message may not need it. 2339 */ 2340 NG_HOOK_UNREF(hook); 2341 hook = NULL; 2342 } 2343 /* 2344 * Similarly, if the node is a zombie there is 2345 * nothing we can do with it, drop everything. 2346 */ 2347 if (NG_NODE_NOT_VALID(node)) { 2348 TRAP_ERROR(); 2349 error = EINVAL; 2350 NG_FREE_ITEM(item); 2351 break; 2352 } 2353 /* 2354 * Call the appropriate message handler for the object. 2355 * It is up to the message handler to free the message. 2356 * If it's a generic message, handle it generically, 2357 * otherwise call the type's message handler (if it exists). 2358 * XXX (race). Remember that a queued message may 2359 * reference a node or hook that has just been 2360 * invalidated. It will exist as the queue code 2361 * is holding a reference, but.. 2362 */ 2363 if ((NGI_MSG(item)->header.typecookie == NGM_GENERIC_COOKIE) && 2364 ((NGI_MSG(item)->header.flags & NGF_RESP) == 0)) { 2365 error = ng_generic_msg(node, item, hook); 2366 break; 2367 } 2368 if (((!hook) || (!(rcvmsg = hook->hk_rcvmsg))) && 2369 (!(rcvmsg = node->nd_type->rcvmsg))) { 2370 TRAP_ERROR(); 2371 error = 0; 2372 NG_FREE_ITEM(item); 2373 break; 2374 } 2375 error = (*rcvmsg)(node, item, hook); 2376 break; 2377 case NGQF_FN: 2378 case NGQF_FN2: 2379 /* 2380 * We have to implicitly trust the hook, 2381 * as some of these are used for system purposes 2382 * where the hook is invalid. In the case of 2383 * the shutdown message we allow it to hit 2384 * even if the node is invalid. 2385 */ 2386 if ((NG_NODE_NOT_VALID(node)) 2387 && (NGI_FN(item) != &ng_rmnode)) { 2388 TRAP_ERROR(); 2389 error = EINVAL; 2390 NG_FREE_ITEM(item); 2391 break; 2392 } 2393 if ((item->el_flags & NGQF_TYPE) == NGQF_FN) { 2394 (*NGI_FN(item))(node, hook, NGI_ARG1(item), 2395 NGI_ARG2(item)); 2396 NG_FREE_ITEM(item); 2397 } else /* it is NGQF_FN2 */ 2398 error = (*NGI_FN2(item))(node, item, hook); 2399 break; 2400 } 2401 /* 2402 * We held references on some of the resources 2403 * that we took from the item. Now that we have 2404 * finished doing everything, drop those references. 2405 */ 2406 if (hook) 2407 NG_HOOK_UNREF(hook); 2408 2409 if (rw == NGQRW_R) 2410 ng_leave_read(&node->nd_input_queue); 2411 else 2412 ng_leave_write(&node->nd_input_queue); 2413 2414 /* Apply callback. */ 2415 if (apply != NULL) { 2416 if (depth == 1 && error != 0) 2417 apply->error = error; 2418 if (refcount_release(&apply->refs)) 2419 (*apply->apply)(apply->context, apply->error); 2420 } 2421 2422 return (error); 2423} 2424 2425/*********************************************************************** 2426 * Implement the 'generic' control messages 2427 ***********************************************************************/ 2428static int 2429ng_generic_msg(node_p here, item_p item, hook_p lasthook) 2430{ 2431 int error = 0; 2432 struct ng_mesg *msg; 2433 struct ng_mesg *resp = NULL; 2434 2435 NGI_GET_MSG(item, msg); 2436 if (msg->header.typecookie != NGM_GENERIC_COOKIE) { 2437 TRAP_ERROR(); 2438 error = EINVAL; 2439 goto out; 2440 } 2441 switch (msg->header.cmd) { 2442 case NGM_SHUTDOWN: 2443 ng_rmnode(here, NULL, NULL, 0); 2444 break; 2445 case NGM_MKPEER: 2446 { 2447 struct ngm_mkpeer *const mkp = (struct ngm_mkpeer *) msg->data; 2448 2449 if (msg->header.arglen != sizeof(*mkp)) { 2450 TRAP_ERROR(); 2451 error = EINVAL; 2452 break; 2453 } 2454 mkp->type[sizeof(mkp->type) - 1] = '\0'; 2455 mkp->ourhook[sizeof(mkp->ourhook) - 1] = '\0'; 2456 mkp->peerhook[sizeof(mkp->peerhook) - 1] = '\0'; 2457 error = ng_mkpeer(here, mkp->ourhook, mkp->peerhook, mkp->type); 2458 break; 2459 } 2460 case NGM_CONNECT: 2461 { 2462 struct ngm_connect *const con = 2463 (struct ngm_connect *) msg->data; 2464 node_p node2; 2465 2466 if (msg->header.arglen != sizeof(*con)) { 2467 TRAP_ERROR(); 2468 error = EINVAL; 2469 break; 2470 } 2471 con->path[sizeof(con->path) - 1] = '\0'; 2472 con->ourhook[sizeof(con->ourhook) - 1] = '\0'; 2473 con->peerhook[sizeof(con->peerhook) - 1] = '\0'; 2474 /* Don't forget we get a reference.. */ 2475 error = ng_path2noderef(here, con->path, &node2, NULL); 2476 if (error) 2477 break; 2478 error = ng_con_nodes(item, here, con->ourhook, 2479 node2, con->peerhook); 2480 NG_NODE_UNREF(node2); 2481 break; 2482 } 2483 case NGM_NAME: 2484 { 2485 struct ngm_name *const nam = (struct ngm_name *) msg->data; 2486 2487 if (msg->header.arglen != sizeof(*nam)) { 2488 TRAP_ERROR(); 2489 error = EINVAL; 2490 break; 2491 } 2492 nam->name[sizeof(nam->name) - 1] = '\0'; 2493 error = ng_name_node(here, nam->name); 2494 break; 2495 } 2496 case NGM_RMHOOK: 2497 { 2498 struct ngm_rmhook *const rmh = (struct ngm_rmhook *) msg->data; 2499 hook_p hook; 2500 2501 if (msg->header.arglen != sizeof(*rmh)) { 2502 TRAP_ERROR(); 2503 error = EINVAL; 2504 break; 2505 } 2506 rmh->ourhook[sizeof(rmh->ourhook) - 1] = '\0'; 2507 if ((hook = ng_findhook(here, rmh->ourhook)) != NULL) 2508 ng_destroy_hook(hook); 2509 break; 2510 } 2511 case NGM_NODEINFO: 2512 { 2513 struct nodeinfo *ni; 2514 2515 NG_MKRESPONSE(resp, msg, sizeof(*ni), M_NOWAIT); 2516 if (resp == NULL) { 2517 error = ENOMEM; 2518 break; 2519 } 2520 2521 /* Fill in node info */ 2522 ni = (struct nodeinfo *) resp->data; 2523 if (NG_NODE_HAS_NAME(here)) 2524 strcpy(ni->name, NG_NODE_NAME(here)); 2525 strcpy(ni->type, here->nd_type->name); 2526 ni->id = ng_node2ID(here); 2527 ni->hooks = here->nd_numhooks; 2528 break; 2529 } 2530 case NGM_LISTHOOKS: 2531 { 2532 const int nhooks = here->nd_numhooks; 2533 struct hooklist *hl; 2534 struct nodeinfo *ni; 2535 hook_p hook; 2536 2537 /* Get response struct */ 2538 NG_MKRESPONSE(resp, msg, sizeof(*hl) 2539 + (nhooks * sizeof(struct linkinfo)), M_NOWAIT); 2540 if (resp == NULL) { 2541 error = ENOMEM; 2542 break; 2543 } 2544 hl = (struct hooklist *) resp->data; 2545 ni = &hl->nodeinfo; 2546 2547 /* Fill in node info */ 2548 if (NG_NODE_HAS_NAME(here)) 2549 strcpy(ni->name, NG_NODE_NAME(here)); 2550 strcpy(ni->type, here->nd_type->name); 2551 ni->id = ng_node2ID(here); 2552 2553 /* Cycle through the linked list of hooks */ 2554 ni->hooks = 0; 2555 LIST_FOREACH(hook, &here->nd_hooks, hk_hooks) { 2556 struct linkinfo *const link = &hl->link[ni->hooks]; 2557 2558 if (ni->hooks >= nhooks) { 2559 log(LOG_ERR, "%s: number of %s changed\n", 2560 __func__, "hooks"); 2561 break; 2562 } 2563 if (NG_HOOK_NOT_VALID(hook)) 2564 continue; 2565 strcpy(link->ourhook, NG_HOOK_NAME(hook)); 2566 strcpy(link->peerhook, NG_PEER_HOOK_NAME(hook)); 2567 if (NG_PEER_NODE_NAME(hook)[0] != '\0') 2568 strcpy(link->nodeinfo.name, 2569 NG_PEER_NODE_NAME(hook)); 2570 strcpy(link->nodeinfo.type, 2571 NG_PEER_NODE(hook)->nd_type->name); 2572 link->nodeinfo.id = ng_node2ID(NG_PEER_NODE(hook)); 2573 link->nodeinfo.hooks = NG_PEER_NODE(hook)->nd_numhooks; 2574 ni->hooks++; 2575 } 2576 break; 2577 } 2578 2579 case NGM_LISTNAMES: 2580 case NGM_LISTNODES: 2581 { 2582 const int unnamed = (msg->header.cmd == NGM_LISTNODES); 2583 struct namelist *nl; 2584 node_p node; 2585 int num = 0, i; 2586 2587 mtx_lock(&ng_namehash_mtx); 2588 /* Count number of nodes */ 2589 for (i = 0; i < NG_NAME_HASH_SIZE; i++) { 2590 LIST_FOREACH(node, &ng_name_hash[i], nd_nodes) { 2591 if (NG_NODE_IS_VALID(node) && 2592 (unnamed || NG_NODE_HAS_NAME(node))) { 2593 num++; 2594 } 2595 } 2596 } 2597 mtx_unlock(&ng_namehash_mtx); 2598 2599 /* Get response struct */ 2600 NG_MKRESPONSE(resp, msg, sizeof(*nl) 2601 + (num * sizeof(struct nodeinfo)), M_NOWAIT); 2602 if (resp == NULL) { 2603 error = ENOMEM; 2604 break; 2605 } 2606 nl = (struct namelist *) resp->data; 2607 2608 /* Cycle through the linked list of nodes */ 2609 nl->numnames = 0; 2610 mtx_lock(&ng_namehash_mtx); 2611 for (i = 0; i < NG_NAME_HASH_SIZE; i++) { 2612 LIST_FOREACH(node, &ng_name_hash[i], nd_nodes) { 2613 struct nodeinfo *const np = 2614 &nl->nodeinfo[nl->numnames]; 2615 2616 if (NG_NODE_NOT_VALID(node)) 2617 continue; 2618 if (!unnamed && (! NG_NODE_HAS_NAME(node))) 2619 continue; 2620 if (nl->numnames >= num) { 2621 log(LOG_ERR, "%s: number of nodes changed\n", 2622 __func__); 2623 break; 2624 } 2625 if (NG_NODE_HAS_NAME(node)) 2626 strcpy(np->name, NG_NODE_NAME(node)); 2627 strcpy(np->type, node->nd_type->name); 2628 np->id = ng_node2ID(node); 2629 np->hooks = node->nd_numhooks; 2630 nl->numnames++; 2631 } 2632 } 2633 mtx_unlock(&ng_namehash_mtx); 2634 break; 2635 } 2636 2637 case NGM_LISTTYPES: 2638 { 2639 struct typelist *tl; 2640 struct ng_type *type; 2641 int num = 0; 2642 2643 mtx_lock(&ng_typelist_mtx); 2644 /* Count number of types */ 2645 LIST_FOREACH(type, &ng_typelist, types) { 2646 num++; 2647 } 2648 mtx_unlock(&ng_typelist_mtx); 2649 2650 /* Get response struct */ 2651 NG_MKRESPONSE(resp, msg, sizeof(*tl) 2652 + (num * sizeof(struct typeinfo)), M_NOWAIT); 2653 if (resp == NULL) { 2654 error = ENOMEM; 2655 break; 2656 } 2657 tl = (struct typelist *) resp->data; 2658 2659 /* Cycle through the linked list of types */ 2660 tl->numtypes = 0; 2661 mtx_lock(&ng_typelist_mtx); 2662 LIST_FOREACH(type, &ng_typelist, types) { 2663 struct typeinfo *const tp = &tl->typeinfo[tl->numtypes]; 2664 2665 if (tl->numtypes >= num) { 2666 log(LOG_ERR, "%s: number of %s changed\n", 2667 __func__, "types"); 2668 break; 2669 } 2670 strcpy(tp->type_name, type->name); 2671 tp->numnodes = type->refs - 1; /* don't count list */ 2672 tl->numtypes++; 2673 } 2674 mtx_unlock(&ng_typelist_mtx); 2675 break; 2676 } 2677 2678 case NGM_BINARY2ASCII: 2679 { 2680 int bufSize = 20 * 1024; /* XXX hard coded constant */ 2681 const struct ng_parse_type *argstype; 2682 const struct ng_cmdlist *c; 2683 struct ng_mesg *binary, *ascii; 2684 2685 /* Data area must contain a valid netgraph message */ 2686 binary = (struct ng_mesg *)msg->data; 2687 if (msg->header.arglen < sizeof(struct ng_mesg) || 2688 (msg->header.arglen - sizeof(struct ng_mesg) < 2689 binary->header.arglen)) { 2690 TRAP_ERROR(); 2691 error = EINVAL; 2692 break; 2693 } 2694 2695 /* Get a response message with lots of room */ 2696 NG_MKRESPONSE(resp, msg, sizeof(*ascii) + bufSize, M_NOWAIT); 2697 if (resp == NULL) { 2698 error = ENOMEM; 2699 break; 2700 } 2701 ascii = (struct ng_mesg *)resp->data; 2702 2703 /* Copy binary message header to response message payload */ 2704 bcopy(binary, ascii, sizeof(*binary)); 2705 2706 /* Find command by matching typecookie and command number */ 2707 for (c = here->nd_type->cmdlist; 2708 c != NULL && c->name != NULL; c++) { 2709 if (binary->header.typecookie == c->cookie 2710 && binary->header.cmd == c->cmd) 2711 break; 2712 } 2713 if (c == NULL || c->name == NULL) { 2714 for (c = ng_generic_cmds; c->name != NULL; c++) { 2715 if (binary->header.typecookie == c->cookie 2716 && binary->header.cmd == c->cmd) 2717 break; 2718 } 2719 if (c->name == NULL) { 2720 NG_FREE_MSG(resp); 2721 error = ENOSYS; 2722 break; 2723 } 2724 } 2725 2726 /* Convert command name to ASCII */ 2727 snprintf(ascii->header.cmdstr, sizeof(ascii->header.cmdstr), 2728 "%s", c->name); 2729 2730 /* Convert command arguments to ASCII */ 2731 argstype = (binary->header.flags & NGF_RESP) ? 2732 c->respType : c->mesgType; 2733 if (argstype == NULL) { 2734 *ascii->data = '\0'; 2735 } else { 2736 if ((error = ng_unparse(argstype, 2737 (u_char *)binary->data, 2738 ascii->data, bufSize)) != 0) { 2739 NG_FREE_MSG(resp); 2740 break; 2741 } 2742 } 2743 2744 /* Return the result as struct ng_mesg plus ASCII string */ 2745 bufSize = strlen(ascii->data) + 1; 2746 ascii->header.arglen = bufSize; 2747 resp->header.arglen = sizeof(*ascii) + bufSize; 2748 break; 2749 } 2750 2751 case NGM_ASCII2BINARY: 2752 { 2753 int bufSize = 2000; /* XXX hard coded constant */ 2754 const struct ng_cmdlist *c; 2755 const struct ng_parse_type *argstype; 2756 struct ng_mesg *ascii, *binary; 2757 int off = 0; 2758 2759 /* Data area must contain at least a struct ng_mesg + '\0' */ 2760 ascii = (struct ng_mesg *)msg->data; 2761 if ((msg->header.arglen < sizeof(*ascii) + 1) || 2762 (ascii->header.arglen < 1) || 2763 (msg->header.arglen < sizeof(*ascii) + 2764 ascii->header.arglen)) { 2765 TRAP_ERROR(); 2766 error = EINVAL; 2767 break; 2768 } 2769 ascii->data[ascii->header.arglen - 1] = '\0'; 2770 2771 /* Get a response message with lots of room */ 2772 NG_MKRESPONSE(resp, msg, sizeof(*binary) + bufSize, M_NOWAIT); 2773 if (resp == NULL) { 2774 error = ENOMEM; 2775 break; 2776 } 2777 binary = (struct ng_mesg *)resp->data; 2778 2779 /* Copy ASCII message header to response message payload */ 2780 bcopy(ascii, binary, sizeof(*ascii)); 2781 2782 /* Find command by matching ASCII command string */ 2783 for (c = here->nd_type->cmdlist; 2784 c != NULL && c->name != NULL; c++) { 2785 if (strcmp(ascii->header.cmdstr, c->name) == 0) 2786 break; 2787 } 2788 if (c == NULL || c->name == NULL) { 2789 for (c = ng_generic_cmds; c->name != NULL; c++) { 2790 if (strcmp(ascii->header.cmdstr, c->name) == 0) 2791 break; 2792 } 2793 if (c->name == NULL) { 2794 NG_FREE_MSG(resp); 2795 error = ENOSYS; 2796 break; 2797 } 2798 } 2799 2800 /* Convert command name to binary */ 2801 binary->header.cmd = c->cmd; 2802 binary->header.typecookie = c->cookie; 2803 2804 /* Convert command arguments to binary */ 2805 argstype = (binary->header.flags & NGF_RESP) ? 2806 c->respType : c->mesgType; 2807 if (argstype == NULL) { 2808 bufSize = 0; 2809 } else { 2810 if ((error = ng_parse(argstype, ascii->data, 2811 &off, (u_char *)binary->data, &bufSize)) != 0) { 2812 NG_FREE_MSG(resp); 2813 break; 2814 } 2815 } 2816 2817 /* Return the result */ 2818 binary->header.arglen = bufSize; 2819 resp->header.arglen = sizeof(*binary) + bufSize; 2820 break; 2821 } 2822 2823 case NGM_TEXT_CONFIG: 2824 case NGM_TEXT_STATUS: 2825 /* 2826 * This one is tricky as it passes the command down to the 2827 * actual node, even though it is a generic type command. 2828 * This means we must assume that the item/msg is already freed 2829 * when control passes back to us. 2830 */ 2831 if (here->nd_type->rcvmsg != NULL) { 2832 NGI_MSG(item) = msg; /* put it back as we found it */ 2833 return((*here->nd_type->rcvmsg)(here, item, lasthook)); 2834 } 2835 /* Fall through if rcvmsg not supported */ 2836 default: 2837 TRAP_ERROR(); 2838 error = EINVAL; 2839 } 2840 /* 2841 * Sometimes a generic message may be statically allocated 2842 * to avoid problems with allocating when in tight memeory situations. 2843 * Don't free it if it is so. 2844 * I break them appart here, because erros may cause a free if the item 2845 * in which case we'd be doing it twice. 2846 * they are kept together above, to simplify freeing. 2847 */ 2848out: 2849 NG_RESPOND_MSG(error, here, item, resp); 2850 if (msg) 2851 NG_FREE_MSG(msg); 2852 return (error); 2853} 2854 2855/************************************************************************ 2856 Queue element get/free routines 2857************************************************************************/ 2858 2859uma_zone_t ng_qzone; 2860static int maxalloc = 4096;/* limit the damage of a leak */ 2861static int maxdata = 512; /* limit the damage of a DoS */ 2862static int useddata = 0; 2863 2864TUNABLE_INT("net.graph.maxalloc", &maxalloc); 2865SYSCTL_INT(_net_graph, OID_AUTO, maxalloc, CTLFLAG_RDTUN, &maxalloc, 2866 0, "Maximum number of queue items to allocate"); 2867TUNABLE_INT("net.graph.maxdata", &maxdata); 2868SYSCTL_INT(_net_graph, OID_AUTO, maxdata, CTLFLAG_RW | CTLFLAG_TUN, &maxdata, 2869 0, "Maximum number of queue data items to allocate"); 2870 2871#ifdef NETGRAPH_DEBUG 2872static TAILQ_HEAD(, ng_item) ng_itemlist = TAILQ_HEAD_INITIALIZER(ng_itemlist); 2873static int allocated; /* number of items malloc'd */ 2874#endif 2875 2876/* 2877 * Get a queue entry. 2878 * This is usually called when a packet first enters netgraph. 2879 * By definition, this is usually from an interrupt, or from a user. 2880 * Users are not so important, but try be quick for the times that it's 2881 * an interrupt. 2882 */ 2883static __inline item_p 2884ng_getqblk(int flags) 2885{ 2886 item_p item = NULL; 2887 int wait; 2888 2889 wait = (flags & NG_WAITOK) ? M_WAITOK : M_NOWAIT; 2890 2891 item = uma_zalloc(ng_qzone, wait | M_ZERO); 2892 2893#ifdef NETGRAPH_DEBUG 2894 if (item) { 2895 mtx_lock(&ngq_mtx); 2896 TAILQ_INSERT_TAIL(&ng_itemlist, item, all); 2897 allocated++; 2898 mtx_unlock(&ngq_mtx); 2899 } 2900#endif 2901 2902 return (item); 2903} 2904 2905/* 2906 * Release a queue entry 2907 */ 2908void 2909ng_free_item(item_p item) 2910{ 2911 /* 2912 * The item may hold resources on it's own. We need to free 2913 * these before we can free the item. What they are depends upon 2914 * what kind of item it is. it is important that nodes zero 2915 * out pointers to resources that they remove from the item 2916 * or we release them again here. 2917 */ 2918 switch (item->el_flags & NGQF_TYPE) { 2919 case NGQF_DATA: 2920 atomic_subtract_int(&useddata, 1); 2921 /* If we have an mbuf still attached.. */ 2922 NG_FREE_M(_NGI_M(item)); 2923 break; 2924 case NGQF_MESG: 2925 _NGI_RETADDR(item) = 0; 2926 NG_FREE_MSG(_NGI_MSG(item)); 2927 break; 2928 case NGQF_FN: 2929 case NGQF_FN2: 2930 /* nothing to free really, */ 2931 _NGI_FN(item) = NULL; 2932 _NGI_ARG1(item) = NULL; 2933 _NGI_ARG2(item) = 0; 2934 break; 2935 } 2936 /* If we still have a node or hook referenced... */ 2937 _NGI_CLR_NODE(item); 2938 _NGI_CLR_HOOK(item); 2939 2940#ifdef NETGRAPH_DEBUG 2941 mtx_lock(&ngq_mtx); 2942 TAILQ_REMOVE(&ng_itemlist, item, all); 2943 allocated--; 2944 mtx_unlock(&ngq_mtx); 2945#endif 2946 uma_zfree(ng_qzone, item); 2947} 2948 2949/************************************************************************ 2950 Module routines 2951************************************************************************/ 2952 2953/* 2954 * Handle the loading/unloading of a netgraph node type module 2955 */ 2956int 2957ng_mod_event(module_t mod, int event, void *data) 2958{ 2959 struct ng_type *const type = data; 2960 int s, error = 0; 2961 2962 switch (event) { 2963 case MOD_LOAD: 2964 2965 /* Register new netgraph node type */ 2966 s = splnet(); 2967 if ((error = ng_newtype(type)) != 0) { 2968 splx(s); 2969 break; 2970 } 2971 2972 /* Call type specific code */ 2973 if (type->mod_event != NULL) 2974 if ((error = (*type->mod_event)(mod, event, data))) { 2975 mtx_lock(&ng_typelist_mtx); 2976 type->refs--; /* undo it */ 2977 LIST_REMOVE(type, types); 2978 mtx_unlock(&ng_typelist_mtx); 2979 } 2980 splx(s); 2981 break; 2982 2983 case MOD_UNLOAD: 2984 s = splnet(); 2985 if (type->refs > 1) { /* make sure no nodes exist! */ 2986 error = EBUSY; 2987 } else { 2988 if (type->refs == 0) { 2989 /* failed load, nothing to undo */ 2990 splx(s); 2991 break; 2992 } 2993 if (type->mod_event != NULL) { /* check with type */ 2994 error = (*type->mod_event)(mod, event, data); 2995 if (error != 0) { /* type refuses.. */ 2996 splx(s); 2997 break; 2998 } 2999 } 3000 mtx_lock(&ng_typelist_mtx); 3001 LIST_REMOVE(type, types); 3002 mtx_unlock(&ng_typelist_mtx); 3003 } 3004 splx(s); 3005 break; 3006 3007 default: 3008 if (type->mod_event != NULL) 3009 error = (*type->mod_event)(mod, event, data); 3010 else 3011 error = EOPNOTSUPP; /* XXX ? */ 3012 break; 3013 } 3014 return (error); 3015} 3016 3017/* 3018 * Handle loading and unloading for this code. 3019 * The only thing we need to link into is the NETISR strucure. 3020 */ 3021static int 3022ngb_mod_event(module_t mod, int event, void *data) 3023{ 3024 int error = 0; 3025 3026 switch (event) { 3027 case MOD_LOAD: 3028 /* Initialize everything. */ 3029 NG_WORKLIST_LOCK_INIT(); 3030 mtx_init(&ng_typelist_mtx, "netgraph types mutex", NULL, 3031 MTX_DEF); 3032 mtx_init(&ng_idhash_mtx, "netgraph idhash mutex", NULL, 3033 MTX_DEF); 3034 mtx_init(&ng_namehash_mtx, "netgraph namehash mutex", NULL, 3035 MTX_DEF); 3036 mtx_init(&ng_topo_mtx, "netgraph topology mutex", NULL, 3037 MTX_DEF); 3038#ifdef NETGRAPH_DEBUG 3039 mtx_init(&ng_nodelist_mtx, "netgraph nodelist mutex", NULL, 3040 MTX_DEF); 3041 mtx_init(&ngq_mtx, "netgraph item list mutex", NULL, 3042 MTX_DEF); 3043#endif 3044 ng_qzone = uma_zcreate("NetGraph items", sizeof(struct ng_item), 3045 NULL, NULL, NULL, NULL, UMA_ALIGN_CACHE, 0); 3046 uma_zone_set_max(ng_qzone, maxalloc); 3047 netisr_register(NETISR_NETGRAPH, (netisr_t *)ngintr, NULL, 3048 NETISR_MPSAFE); 3049 break; 3050 case MOD_UNLOAD: 3051 /* You can't unload it because an interface may be using it. */ 3052 error = EBUSY; 3053 break; 3054 default: 3055 error = EOPNOTSUPP; 3056 break; 3057 } 3058 return (error); 3059} 3060 3061static moduledata_t netgraph_mod = { 3062 "netgraph", 3063 ngb_mod_event, 3064 (NULL) 3065}; 3066DECLARE_MODULE(netgraph, netgraph_mod, SI_SUB_NETGRAPH, SI_ORDER_MIDDLE); 3067SYSCTL_NODE(_net, OID_AUTO, graph, CTLFLAG_RW, 0, "netgraph Family"); 3068SYSCTL_INT(_net_graph, OID_AUTO, abi_version, CTLFLAG_RD, 0, NG_ABI_VERSION,""); 3069SYSCTL_INT(_net_graph, OID_AUTO, msg_version, CTLFLAG_RD, 0, NG_VERSION, ""); 3070 3071#ifdef NETGRAPH_DEBUG 3072void 3073dumphook (hook_p hook, char *file, int line) 3074{ 3075 printf("hook: name %s, %d refs, Last touched:\n", 3076 _NG_HOOK_NAME(hook), hook->hk_refs); 3077 printf(" Last active @ %s, line %d\n", 3078 hook->lastfile, hook->lastline); 3079 if (line) { 3080 printf(" problem discovered at file %s, line %d\n", file, line); 3081 } 3082} 3083 3084void 3085dumpnode(node_p node, char *file, int line) 3086{ 3087 printf("node: ID [%x]: type '%s', %d hooks, flags 0x%x, %d refs, %s:\n", 3088 _NG_NODE_ID(node), node->nd_type->name, 3089 node->nd_numhooks, node->nd_flags, 3090 node->nd_refs, node->nd_name); 3091 printf(" Last active @ %s, line %d\n", 3092 node->lastfile, node->lastline); 3093 if (line) { 3094 printf(" problem discovered at file %s, line %d\n", file, line); 3095 } 3096} 3097 3098void 3099dumpitem(item_p item, char *file, int line) 3100{ 3101 printf(" ACTIVE item, last used at %s, line %d", 3102 item->lastfile, item->lastline); 3103 switch(item->el_flags & NGQF_TYPE) { 3104 case NGQF_DATA: 3105 printf(" - [data]\n"); 3106 break; 3107 case NGQF_MESG: 3108 printf(" - retaddr[%d]:\n", _NGI_RETADDR(item)); 3109 break; 3110 case NGQF_FN: 3111 printf(" - fn@%p (%p, %p, %p, %d (%x))\n", 3112 _NGI_FN(item), 3113 _NGI_NODE(item), 3114 _NGI_HOOK(item), 3115 item->body.fn.fn_arg1, 3116 item->body.fn.fn_arg2, 3117 item->body.fn.fn_arg2); 3118 break; 3119 case NGQF_FN2: 3120 printf(" - fn2@%p (%p, %p, %p, %d (%x))\n", 3121 _NGI_FN2(item), 3122 _NGI_NODE(item), 3123 _NGI_HOOK(item), 3124 item->body.fn.fn_arg1, 3125 item->body.fn.fn_arg2, 3126 item->body.fn.fn_arg2); 3127 break; 3128 } 3129 if (line) { 3130 printf(" problem discovered at file %s, line %d\n", file, line); 3131 if (_NGI_NODE(item)) { 3132 printf("node %p ([%x])\n", 3133 _NGI_NODE(item), ng_node2ID(_NGI_NODE(item))); 3134 } 3135 } 3136} 3137 3138static void 3139ng_dumpitems(void) 3140{ 3141 item_p item; 3142 int i = 1; 3143 TAILQ_FOREACH(item, &ng_itemlist, all) { 3144 printf("[%d] ", i++); 3145 dumpitem(item, NULL, 0); 3146 } 3147} 3148 3149static void 3150ng_dumpnodes(void) 3151{ 3152 node_p node; 3153 int i = 1; 3154 mtx_lock(&ng_nodelist_mtx); 3155 SLIST_FOREACH(node, &ng_allnodes, nd_all) { 3156 printf("[%d] ", i++); 3157 dumpnode(node, NULL, 0); 3158 } 3159 mtx_unlock(&ng_nodelist_mtx); 3160} 3161 3162static void 3163ng_dumphooks(void) 3164{ 3165 hook_p hook; 3166 int i = 1; 3167 mtx_lock(&ng_nodelist_mtx); 3168 SLIST_FOREACH(hook, &ng_allhooks, hk_all) { 3169 printf("[%d] ", i++); 3170 dumphook(hook, NULL, 0); 3171 } 3172 mtx_unlock(&ng_nodelist_mtx); 3173} 3174 3175static int 3176sysctl_debug_ng_dump_items(SYSCTL_HANDLER_ARGS) 3177{ 3178 int error; 3179 int val; 3180 int i; 3181 3182 val = allocated; 3183 i = 1; 3184 error = sysctl_handle_int(oidp, &val, 0, req); 3185 if (error != 0 || req->newptr == NULL) 3186 return (error); 3187 if (val == 42) { 3188 ng_dumpitems(); 3189 ng_dumpnodes(); 3190 ng_dumphooks(); 3191 } 3192 return (0); 3193} 3194 3195SYSCTL_PROC(_debug, OID_AUTO, ng_dump_items, CTLTYPE_INT | CTLFLAG_RW, 3196 0, sizeof(int), sysctl_debug_ng_dump_items, "I", "Number of allocated items"); 3197#endif /* NETGRAPH_DEBUG */ 3198 3199 3200/*********************************************************************** 3201* Worklist routines 3202**********************************************************************/ 3203/* NETISR thread enters here */ 3204/* 3205 * Pick a node off the list of nodes with work, 3206 * try get an item to process off it. 3207 * If there are no more, remove the node from the list. 3208 */ 3209static void 3210ngintr(void) 3211{ 3212 for (;;) { 3213 node_p node; 3214 3215 /* Get node from the worklist. */ 3216 NG_WORKLIST_LOCK(); 3217 node = TAILQ_FIRST(&ng_worklist); 3218 if (!node) { 3219 NG_WORKLIST_UNLOCK(); 3220 break; 3221 } 3222 TAILQ_REMOVE(&ng_worklist, node, nd_work); 3223 NG_WORKLIST_UNLOCK(); 3224 CTR3(KTR_NET, "%20s: node [%x] (%p) taken off worklist", 3225 __func__, node->nd_ID, node); 3226 /* 3227 * We have the node. We also take over the reference 3228 * that the list had on it. 3229 * Now process as much as you can, until it won't 3230 * let you have another item off the queue. 3231 * All this time, keep the reference 3232 * that lets us be sure that the node still exists. 3233 * Let the reference go at the last minute. 3234 */ 3235 for (;;) { 3236 item_p item; 3237 int rw; 3238 3239 NG_QUEUE_LOCK(&node->nd_input_queue); 3240 item = ng_dequeue(&node->nd_input_queue, &rw); 3241 if (item == NULL) { 3242 atomic_clear_int(&node->nd_flags, NGF_WORKQ); 3243 NG_QUEUE_UNLOCK(&node->nd_input_queue); 3244 break; /* go look for another node */ 3245 } else { 3246 NG_QUEUE_UNLOCK(&node->nd_input_queue); 3247 NGI_GET_NODE(item, node); /* zaps stored node */ 3248 ng_apply_item(node, item, rw); 3249 NG_NODE_UNREF(node); 3250 } 3251 } 3252 NG_NODE_UNREF(node); 3253 } 3254} 3255 3256/* 3257 * XXX 3258 * It's posible that a debugging NG_NODE_REF may need 3259 * to be outside the mutex zone 3260 */ 3261static void 3262ng_worklist_add(node_p node) 3263{ 3264 3265 mtx_assert(&node->nd_input_queue.q_mtx, MA_OWNED); 3266 3267 if ((node->nd_flags & NGF_WORKQ) == 0) { 3268 /* 3269 * If we are not already on the work queue, 3270 * then put us on. 3271 */ 3272 atomic_set_int(&node->nd_flags, NGF_WORKQ); 3273 NG_NODE_REF(node); /* XXX fafe in mutex? */ 3274 NG_WORKLIST_LOCK(); 3275 TAILQ_INSERT_TAIL(&ng_worklist, node, nd_work); 3276 NG_WORKLIST_UNLOCK(); 3277 schednetisr(NETISR_NETGRAPH); 3278 CTR3(KTR_NET, "%20s: node [%x] (%p) put on worklist", __func__, 3279 node->nd_ID, node); 3280 } else { 3281 CTR3(KTR_NET, "%20s: node [%x] (%p) already on worklist", 3282 __func__, node->nd_ID, node); 3283 } 3284} 3285 3286 3287/*********************************************************************** 3288* Externally useable functions to set up a queue item ready for sending 3289***********************************************************************/ 3290 3291#ifdef NETGRAPH_DEBUG 3292#define ITEM_DEBUG_CHECKS \ 3293 do { \ 3294 if (NGI_NODE(item) ) { \ 3295 printf("item already has node"); \ 3296 kdb_enter(KDB_WHY_NETGRAPH, "has node"); \ 3297 NGI_CLR_NODE(item); \ 3298 } \ 3299 if (NGI_HOOK(item) ) { \ 3300 printf("item already has hook"); \ 3301 kdb_enter(KDB_WHY_NETGRAPH, "has hook"); \ 3302 NGI_CLR_HOOK(item); \ 3303 } \ 3304 } while (0) 3305#else 3306#define ITEM_DEBUG_CHECKS 3307#endif 3308 3309/* 3310 * Put mbuf into the item. 3311 * Hook and node references will be removed when the item is dequeued. 3312 * (or equivalent) 3313 * (XXX) Unsafe because no reference held by peer on remote node. 3314 * remote node might go away in this timescale. 3315 * We know the hooks can't go away because that would require getting 3316 * a writer item on both nodes and we must have at least a reader 3317 * here to be able to do this. 3318 * Note that the hook loaded is the REMOTE hook. 3319 * 3320 * This is possibly in the critical path for new data. 3321 */ 3322item_p 3323ng_package_data(struct mbuf *m, int flags) 3324{ 3325 item_p item; 3326 3327 if (atomic_fetchadd_int(&useddata, 1) >= maxdata) { 3328 atomic_subtract_int(&useddata, 1); 3329 NG_FREE_M(m); 3330 return (NULL); 3331 } 3332 if ((item = ng_getqblk(flags)) == NULL) { 3333 NG_FREE_M(m); 3334 return (NULL); 3335 } 3336 ITEM_DEBUG_CHECKS; 3337 item->el_flags = NGQF_DATA | NGQF_READER; 3338 NGI_M(item) = m; 3339 return (item); 3340} 3341 3342/* 3343 * Allocate a queue item and put items into it.. 3344 * Evaluate the address as this will be needed to queue it and 3345 * to work out what some of the fields should be. 3346 * Hook and node references will be removed when the item is dequeued. 3347 * (or equivalent) 3348 */ 3349item_p 3350ng_package_msg(struct ng_mesg *msg, int flags) 3351{ 3352 item_p item; 3353 3354 if ((item = ng_getqblk(flags)) == NULL) { 3355 NG_FREE_MSG(msg); 3356 return (NULL); 3357 } 3358 ITEM_DEBUG_CHECKS; 3359 /* Messages items count as writers unless explicitly exempted. */ 3360 if (msg->header.cmd & NGM_READONLY) 3361 item->el_flags = NGQF_MESG | NGQF_READER; 3362 else 3363 item->el_flags = NGQF_MESG | NGQF_WRITER; 3364 /* 3365 * Set the current lasthook into the queue item 3366 */ 3367 NGI_MSG(item) = msg; 3368 NGI_RETADDR(item) = 0; 3369 return (item); 3370} 3371 3372 3373 3374#define SET_RETADDR(item, here, retaddr) \ 3375 do { /* Data or fn items don't have retaddrs */ \ 3376 if ((item->el_flags & NGQF_TYPE) == NGQF_MESG) { \ 3377 if (retaddr) { \ 3378 NGI_RETADDR(item) = retaddr; \ 3379 } else { \ 3380 /* \ 3381 * The old return address should be ok. \ 3382 * If there isn't one, use the address \ 3383 * here. \ 3384 */ \ 3385 if (NGI_RETADDR(item) == 0) { \ 3386 NGI_RETADDR(item) \ 3387 = ng_node2ID(here); \ 3388 } \ 3389 } \ 3390 } \ 3391 } while (0) 3392 3393int 3394ng_address_hook(node_p here, item_p item, hook_p hook, ng_ID_t retaddr) 3395{ 3396 hook_p peer; 3397 node_p peernode; 3398 ITEM_DEBUG_CHECKS; 3399 /* 3400 * Quick sanity check.. 3401 * Since a hook holds a reference on it's node, once we know 3402 * that the peer is still connected (even if invalid,) we know 3403 * that the peer node is present, though maybe invalid. 3404 */ 3405 if ((hook == NULL) 3406 || NG_HOOK_NOT_VALID(hook) 3407 || NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook)) 3408 || NG_NODE_NOT_VALID(NG_PEER_NODE(hook))) { 3409 NG_FREE_ITEM(item); 3410 TRAP_ERROR(); 3411 return (ENETDOWN); 3412 } 3413 3414 /* 3415 * Transfer our interest to the other (peer) end. 3416 */ 3417 peer = NG_HOOK_PEER(hook); 3418 NG_HOOK_REF(peer); 3419 NGI_SET_HOOK(item, peer); 3420 peernode = NG_PEER_NODE(hook); 3421 NG_NODE_REF(peernode); 3422 NGI_SET_NODE(item, peernode); 3423 SET_RETADDR(item, here, retaddr); 3424 return (0); 3425} 3426 3427int 3428ng_address_path(node_p here, item_p item, char *address, ng_ID_t retaddr) 3429{ 3430 node_p dest = NULL; 3431 hook_p hook = NULL; 3432 int error; 3433 3434 ITEM_DEBUG_CHECKS; 3435 /* 3436 * Note that ng_path2noderef increments the reference count 3437 * on the node for us if it finds one. So we don't have to. 3438 */ 3439 error = ng_path2noderef(here, address, &dest, &hook); 3440 if (error) { 3441 NG_FREE_ITEM(item); 3442 return (error); 3443 } 3444 NGI_SET_NODE(item, dest); 3445 if ( hook) { 3446 NG_HOOK_REF(hook); /* don't let it go while on the queue */ 3447 NGI_SET_HOOK(item, hook); 3448 } 3449 SET_RETADDR(item, here, retaddr); 3450 return (0); 3451} 3452 3453int 3454ng_address_ID(node_p here, item_p item, ng_ID_t ID, ng_ID_t retaddr) 3455{ 3456 node_p dest; 3457 3458 ITEM_DEBUG_CHECKS; 3459 /* 3460 * Find the target node. 3461 */ 3462 dest = ng_ID2noderef(ID); /* GETS REFERENCE! */ 3463 if (dest == NULL) { 3464 NG_FREE_ITEM(item); 3465 TRAP_ERROR(); 3466 return(EINVAL); 3467 } 3468 /* Fill out the contents */ 3469 NGI_SET_NODE(item, dest); 3470 NGI_CLR_HOOK(item); 3471 SET_RETADDR(item, here, retaddr); 3472 return (0); 3473} 3474 3475/* 3476 * special case to send a message to self (e.g. destroy node) 3477 * Possibly indicate an arrival hook too. 3478 * Useful for removing that hook :-) 3479 */ 3480item_p 3481ng_package_msg_self(node_p here, hook_p hook, struct ng_mesg *msg) 3482{ 3483 item_p item; 3484 3485 /* 3486 * Find the target node. 3487 * If there is a HOOK argument, then use that in preference 3488 * to the address. 3489 */ 3490 if ((item = ng_getqblk(NG_NOFLAGS)) == NULL) { 3491 NG_FREE_MSG(msg); 3492 return (NULL); 3493 } 3494 3495 /* Fill out the contents */ 3496 item->el_flags = NGQF_MESG | NGQF_WRITER; 3497 NG_NODE_REF(here); 3498 NGI_SET_NODE(item, here); 3499 if (hook) { 3500 NG_HOOK_REF(hook); 3501 NGI_SET_HOOK(item, hook); 3502 } 3503 NGI_MSG(item) = msg; 3504 NGI_RETADDR(item) = ng_node2ID(here); 3505 return (item); 3506} 3507 3508/* 3509 * Send ng_item_fn function call to the specified node. 3510 */ 3511 3512int 3513ng_send_fn(node_p node, hook_p hook, ng_item_fn *fn, void * arg1, int arg2) 3514{ 3515 3516 return ng_send_fn1(node, hook, fn, arg1, arg2, NG_NOFLAGS); 3517} 3518 3519int 3520ng_send_fn1(node_p node, hook_p hook, ng_item_fn *fn, void * arg1, int arg2, 3521 int flags) 3522{ 3523 item_p item; 3524 3525 if ((item = ng_getqblk(flags)) == NULL) { 3526 return (ENOMEM); 3527 } 3528 item->el_flags = NGQF_FN | NGQF_WRITER; 3529 NG_NODE_REF(node); /* and one for the item */ 3530 NGI_SET_NODE(item, node); 3531 if (hook) { 3532 NG_HOOK_REF(hook); 3533 NGI_SET_HOOK(item, hook); 3534 } 3535 NGI_FN(item) = fn; 3536 NGI_ARG1(item) = arg1; 3537 NGI_ARG2(item) = arg2; 3538 return(ng_snd_item(item, flags)); 3539} 3540 3541/* 3542 * Send ng_item_fn2 function call to the specified node. 3543 * 3544 * If an optional pitem parameter is supplied, its apply 3545 * callback will be copied to the new item. If also NG_REUSE_ITEM 3546 * flag is set, no new item will be allocated, but pitem will 3547 * be used. 3548 */ 3549int 3550ng_send_fn2(node_p node, hook_p hook, item_p pitem, ng_item_fn2 *fn, void *arg1, 3551 int arg2, int flags) 3552{ 3553 item_p item; 3554 3555 KASSERT((pitem != NULL || (flags & NG_REUSE_ITEM) == 0), 3556 ("%s: NG_REUSE_ITEM but no pitem", __func__)); 3557 3558 /* 3559 * Allocate a new item if no supplied or 3560 * if we can't use supplied one. 3561 */ 3562 if (pitem == NULL || (flags & NG_REUSE_ITEM) == 0) { 3563 if ((item = ng_getqblk(flags)) == NULL) 3564 return (ENOMEM); 3565 } else { 3566 if ((pitem->el_flags & NGQF_TYPE) == NGQF_DATA) 3567 atomic_subtract_int(&useddata, 1); 3568 item = pitem; 3569 } 3570 3571 item->el_flags = NGQF_FN2 | NGQF_WRITER; 3572 NG_NODE_REF(node); /* and one for the item */ 3573 NGI_SET_NODE(item, node); 3574 if (hook) { 3575 NG_HOOK_REF(hook); 3576 NGI_SET_HOOK(item, hook); 3577 } 3578 NGI_FN2(item) = fn; 3579 NGI_ARG1(item) = arg1; 3580 NGI_ARG2(item) = arg2; 3581 if (pitem != NULL && (flags & NG_REUSE_ITEM) == 0) 3582 item->apply = pitem->apply; 3583 return(ng_snd_item(item, flags)); 3584} 3585 3586/* 3587 * Official timeout routines for Netgraph nodes. 3588 */ 3589static void 3590ng_callout_trampoline(void *arg) 3591{ 3592 item_p item = arg; 3593 3594 ng_snd_item(item, 0); 3595} 3596 3597 3598int 3599ng_callout(struct callout *c, node_p node, hook_p hook, int ticks, 3600 ng_item_fn *fn, void * arg1, int arg2) 3601{ 3602 item_p item, oitem; 3603 3604 if ((item = ng_getqblk(NG_NOFLAGS)) == NULL) 3605 return (ENOMEM); 3606 3607 item->el_flags = NGQF_FN | NGQF_WRITER; 3608 NG_NODE_REF(node); /* and one for the item */ 3609 NGI_SET_NODE(item, node); 3610 if (hook) { 3611 NG_HOOK_REF(hook); 3612 NGI_SET_HOOK(item, hook); 3613 } 3614 NGI_FN(item) = fn; 3615 NGI_ARG1(item) = arg1; 3616 NGI_ARG2(item) = arg2; 3617 oitem = c->c_arg; 3618 if (callout_reset(c, ticks, &ng_callout_trampoline, item) == 1 && 3619 oitem != NULL) 3620 NG_FREE_ITEM(oitem); 3621 return (0); 3622} 3623 3624/* A special modified version of untimeout() */ 3625int 3626ng_uncallout(struct callout *c, node_p node) 3627{ 3628 item_p item; 3629 int rval; 3630 3631 KASSERT(c != NULL, ("ng_uncallout: NULL callout")); 3632 KASSERT(node != NULL, ("ng_uncallout: NULL node")); 3633 3634 rval = callout_stop(c); 3635 item = c->c_arg; 3636 /* Do an extra check */ 3637 if ((rval > 0) && (c->c_func == &ng_callout_trampoline) && 3638 (NGI_NODE(item) == node)) { 3639 /* 3640 * We successfully removed it from the queue before it ran 3641 * So now we need to unreference everything that was 3642 * given extra references. (NG_FREE_ITEM does this). 3643 */ 3644 NG_FREE_ITEM(item); 3645 } 3646 c->c_arg = NULL; 3647 3648 return (rval); 3649} 3650 3651/* 3652 * Set the address, if none given, give the node here. 3653 */ 3654void 3655ng_replace_retaddr(node_p here, item_p item, ng_ID_t retaddr) 3656{ 3657 if (retaddr) { 3658 NGI_RETADDR(item) = retaddr; 3659 } else { 3660 /* 3661 * The old return address should be ok. 3662 * If there isn't one, use the address here. 3663 */ 3664 NGI_RETADDR(item) = ng_node2ID(here); 3665 } 3666} 3667 3668#define TESTING 3669#ifdef TESTING 3670/* just test all the macros */ 3671void 3672ng_macro_test(item_p item); 3673void 3674ng_macro_test(item_p item) 3675{ 3676 node_p node = NULL; 3677 hook_p hook = NULL; 3678 struct mbuf *m; 3679 struct ng_mesg *msg; 3680 ng_ID_t retaddr; 3681 int error; 3682 3683 NGI_GET_M(item, m); 3684 NGI_GET_MSG(item, msg); 3685 retaddr = NGI_RETADDR(item); 3686 NG_SEND_DATA(error, hook, m, NULL); 3687 NG_SEND_DATA_ONLY(error, hook, m); 3688 NG_FWD_NEW_DATA(error, item, hook, m); 3689 NG_FWD_ITEM_HOOK(error, item, hook); 3690 NG_SEND_MSG_HOOK(error, node, msg, hook, retaddr); 3691 NG_SEND_MSG_ID(error, node, msg, retaddr, retaddr); 3692 NG_SEND_MSG_PATH(error, node, msg, ".:", retaddr); 3693 NG_FWD_MSG_HOOK(error, node, item, hook, retaddr); 3694} 3695#endif /* TESTING */ 3696 3697