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 * $FreeBSD$ 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 <sys/unistd.h> 65 #include <sys/kthread.h> 66 #include <sys/smp.h> 67 #include <machine/cpu.h> 68 69 #include <net/netisr.h> 70 #include <net/vnet.h> 71 72 #include <netgraph/ng_message.h> 73 #include <netgraph/netgraph.h> 74 #include <netgraph/ng_parse.h> 75 76 MODULE_VERSION(netgraph, NG_ABI_VERSION); 77 78 /* Mutex to protect topology events. */ 79 static struct mtx ng_topo_mtx; 80 81 #ifdef NETGRAPH_DEBUG 82 static struct mtx ng_nodelist_mtx; /* protects global node/hook lists */ 83 static struct mtx ngq_mtx; /* protects the queue item list */ 84 85 static SLIST_HEAD(, ng_node) ng_allnodes; 86 static LIST_HEAD(, ng_node) ng_freenodes; /* in debug, we never free() them */ 87 static SLIST_HEAD(, ng_hook) ng_allhooks; 88 static LIST_HEAD(, ng_hook) ng_freehooks; /* in debug, we never free() them */ 89 90 static void ng_dumpitems(void); 91 static void ng_dumpnodes(void); 92 static void ng_dumphooks(void); 93 94 #endif /* NETGRAPH_DEBUG */ 95 /* 96 * DEAD versions of the structures. 97 * In order to avoid races, it is sometimes neccesary to point 98 * at SOMETHING even though theoretically, the current entity is 99 * INVALID. Use these to avoid these races. 100 */ 101 struct ng_type ng_deadtype = { 102 NG_ABI_VERSION, 103 "dead", 104 NULL, /* modevent */ 105 NULL, /* constructor */ 106 NULL, /* rcvmsg */ 107 NULL, /* shutdown */ 108 NULL, /* newhook */ 109 NULL, /* findhook */ 110 NULL, /* connect */ 111 NULL, /* rcvdata */ 112 NULL, /* disconnect */ 113 NULL, /* cmdlist */ 114 }; 115 116 struct ng_node ng_deadnode = { 117 "dead", 118 &ng_deadtype, 119 NGF_INVALID, 120 0, /* numhooks */ 121 NULL, /* private */ 122 0, /* ID */ 123 LIST_HEAD_INITIALIZER(ng_deadnode.nd_hooks), 124 {}, /* all_nodes list entry */ 125 {}, /* id hashtable list entry */ 126 { 0, 127 0, 128 {}, /* should never use! (should hang) */ 129 {}, /* workqueue entry */ 130 STAILQ_HEAD_INITIALIZER(ng_deadnode.nd_input_queue.queue), 131 }, 132 1, /* refs */ 133 NULL, /* vnet */ 134 #ifdef NETGRAPH_DEBUG 135 ND_MAGIC, 136 __FILE__, 137 __LINE__, 138 {NULL} 139 #endif /* NETGRAPH_DEBUG */ 140 }; 141 142 struct ng_hook ng_deadhook = { 143 "dead", 144 NULL, /* private */ 145 HK_INVALID | HK_DEAD, 146 0, /* undefined data link type */ 147 &ng_deadhook, /* Peer is self */ 148 &ng_deadnode, /* attached to deadnode */ 149 {}, /* hooks list */ 150 NULL, /* override rcvmsg() */ 151 NULL, /* override rcvdata() */ 152 1, /* refs always >= 1 */ 153 #ifdef NETGRAPH_DEBUG 154 HK_MAGIC, 155 __FILE__, 156 __LINE__, 157 {NULL} 158 #endif /* NETGRAPH_DEBUG */ 159 }; 160 161 /* 162 * END DEAD STRUCTURES 163 */ 164 /* List nodes with unallocated work */ 165 static STAILQ_HEAD(, ng_node) ng_worklist = STAILQ_HEAD_INITIALIZER(ng_worklist); 166 static struct mtx ng_worklist_mtx; /* MUST LOCK NODE FIRST */ 167 168 /* List of installed types */ 169 static LIST_HEAD(, ng_type) ng_typelist; 170 static struct mtx ng_typelist_mtx; 171 172 /* Hash related definitions */ 173 /* XXX Don't need to initialise them because it's a LIST */ 174 static VNET_DEFINE(LIST_HEAD(, ng_node), ng_ID_hash[NG_ID_HASH_SIZE]); 175 #define V_ng_ID_hash VNET(ng_ID_hash) 176 177 static struct mtx ng_idhash_mtx; 178 /* Method to find a node.. used twice so do it here */ 179 #define NG_IDHASH_FN(ID) ((ID) % (NG_ID_HASH_SIZE)) 180 #define NG_IDHASH_FIND(ID, node) \ 181 do { \ 182 mtx_assert(&ng_idhash_mtx, MA_OWNED); \ 183 LIST_FOREACH(node, &V_ng_ID_hash[NG_IDHASH_FN(ID)], \ 184 nd_idnodes) { \ 185 if (NG_NODE_IS_VALID(node) \ 186 && (NG_NODE_ID(node) == ID)) { \ 187 break; \ 188 } \ 189 } \ 190 } while (0) 191 192 static VNET_DEFINE(LIST_HEAD(, ng_node), ng_name_hash[NG_NAME_HASH_SIZE]); 193 #define V_ng_name_hash VNET(ng_name_hash) 194 195 static struct mtx ng_namehash_mtx; 196 #define NG_NAMEHASH(NAME, HASH) \ 197 do { \ 198 u_char h = 0; \ 199 const u_char *c; \ 200 for (c = (const u_char*)(NAME); *c; c++)\ 201 h += *c; \ 202 (HASH) = h % (NG_NAME_HASH_SIZE); \ 203 } while (0) 204 205 206 /* Internal functions */ 207 static int ng_add_hook(node_p node, const char *name, hook_p * hookp); 208 static int ng_generic_msg(node_p here, item_p item, hook_p lasthook); 209 static ng_ID_t ng_decodeidname(const char *name); 210 static int ngb_mod_event(module_t mod, int event, void *data); 211 static void ng_worklist_add(node_p node); 212 static void ngthread(void *); 213 static int ng_apply_item(node_p node, item_p item, int rw); 214 static void ng_flush_input_queue(node_p node); 215 static node_p ng_ID2noderef(ng_ID_t ID); 216 static int ng_con_nodes(item_p item, node_p node, const char *name, 217 node_p node2, const char *name2); 218 static int ng_con_part2(node_p node, item_p item, hook_p hook); 219 static int ng_con_part3(node_p node, item_p item, hook_p hook); 220 static int ng_mkpeer(node_p node, const char *name, 221 const char *name2, char *type); 222 223 /* Imported, these used to be externally visible, some may go back. */ 224 void ng_destroy_hook(hook_p hook); 225 int ng_path2noderef(node_p here, const char *path, 226 node_p *dest, hook_p *lasthook); 227 int ng_make_node(const char *type, node_p *nodepp); 228 int ng_path_parse(char *addr, char **node, char **path, char **hook); 229 void ng_rmnode(node_p node, hook_p dummy1, void *dummy2, int dummy3); 230 void ng_unname(node_p node); 231 232 233 /* Our own netgraph malloc type */ 234 MALLOC_DEFINE(M_NETGRAPH, "netgraph", "netgraph structures and ctrl messages"); 235 MALLOC_DEFINE(M_NETGRAPH_MSG, "netgraph_msg", "netgraph name storage"); 236 static MALLOC_DEFINE(M_NETGRAPH_HOOK, "netgraph_hook", 237 "netgraph hook structures"); 238 static MALLOC_DEFINE(M_NETGRAPH_NODE, "netgraph_node", 239 "netgraph node structures"); 240 static MALLOC_DEFINE(M_NETGRAPH_ITEM, "netgraph_item", 241 "netgraph item structures"); 242 243 /* Should not be visible outside this file */ 244 245 #define _NG_ALLOC_HOOK(hook) \ 246 hook = malloc(sizeof(*hook), M_NETGRAPH_HOOK, M_NOWAIT | M_ZERO) 247 #define _NG_ALLOC_NODE(node) \ 248 node = malloc(sizeof(*node), M_NETGRAPH_NODE, M_NOWAIT | M_ZERO) 249 250 #define NG_QUEUE_LOCK_INIT(n) \ 251 mtx_init(&(n)->q_mtx, "ng_node", NULL, MTX_DEF) 252 #define NG_QUEUE_LOCK(n) \ 253 mtx_lock(&(n)->q_mtx) 254 #define NG_QUEUE_UNLOCK(n) \ 255 mtx_unlock(&(n)->q_mtx) 256 #define NG_WORKLIST_LOCK_INIT() \ 257 mtx_init(&ng_worklist_mtx, "ng_worklist", NULL, MTX_DEF) 258 #define NG_WORKLIST_LOCK() \ 259 mtx_lock(&ng_worklist_mtx) 260 #define NG_WORKLIST_UNLOCK() \ 261 mtx_unlock(&ng_worklist_mtx) 262 #define NG_WORKLIST_SLEEP() \ 263 mtx_sleep(&ng_worklist, &ng_worklist_mtx, PI_NET, "sleep", 0) 264 #define NG_WORKLIST_WAKEUP() \ 265 wakeup_one(&ng_worklist) 266 267 #ifdef NETGRAPH_DEBUG /*----------------------------------------------*/ 268 /* 269 * In debug mode: 270 * In an attempt to help track reference count screwups 271 * we do not free objects back to the malloc system, but keep them 272 * in a local cache where we can examine them and keep information safely 273 * after they have been freed. 274 * We use this scheme for nodes and hooks, and to some extent for items. 275 */ 276 static __inline hook_p 277 ng_alloc_hook(void) 278 { 279 hook_p hook; 280 SLIST_ENTRY(ng_hook) temp; 281 mtx_lock(&ng_nodelist_mtx); 282 hook = LIST_FIRST(&ng_freehooks); 283 if (hook) { 284 LIST_REMOVE(hook, hk_hooks); 285 bcopy(&hook->hk_all, &temp, sizeof(temp)); 286 bzero(hook, sizeof(struct ng_hook)); 287 bcopy(&temp, &hook->hk_all, sizeof(temp)); 288 mtx_unlock(&ng_nodelist_mtx); 289 hook->hk_magic = HK_MAGIC; 290 } else { 291 mtx_unlock(&ng_nodelist_mtx); 292 _NG_ALLOC_HOOK(hook); 293 if (hook) { 294 hook->hk_magic = HK_MAGIC; 295 mtx_lock(&ng_nodelist_mtx); 296 SLIST_INSERT_HEAD(&ng_allhooks, hook, hk_all); 297 mtx_unlock(&ng_nodelist_mtx); 298 } 299 } 300 return (hook); 301 } 302 303 static __inline node_p 304 ng_alloc_node(void) 305 { 306 node_p node; 307 SLIST_ENTRY(ng_node) temp; 308 mtx_lock(&ng_nodelist_mtx); 309 node = LIST_FIRST(&ng_freenodes); 310 if (node) { 311 LIST_REMOVE(node, nd_nodes); 312 bcopy(&node->nd_all, &temp, sizeof(temp)); 313 bzero(node, sizeof(struct ng_node)); 314 bcopy(&temp, &node->nd_all, sizeof(temp)); 315 mtx_unlock(&ng_nodelist_mtx); 316 node->nd_magic = ND_MAGIC; 317 } else { 318 mtx_unlock(&ng_nodelist_mtx); 319 _NG_ALLOC_NODE(node); 320 if (node) { 321 node->nd_magic = ND_MAGIC; 322 mtx_lock(&ng_nodelist_mtx); 323 SLIST_INSERT_HEAD(&ng_allnodes, node, nd_all); 324 mtx_unlock(&ng_nodelist_mtx); 325 } 326 } 327 return (node); 328 } 329 330 #define NG_ALLOC_HOOK(hook) do { (hook) = ng_alloc_hook(); } while (0) 331 #define NG_ALLOC_NODE(node) do { (node) = ng_alloc_node(); } while (0) 332 333 334 #define NG_FREE_HOOK(hook) \ 335 do { \ 336 mtx_lock(&ng_nodelist_mtx); \ 337 LIST_INSERT_HEAD(&ng_freehooks, hook, hk_hooks); \ 338 hook->hk_magic = 0; \ 339 mtx_unlock(&ng_nodelist_mtx); \ 340 } while (0) 341 342 #define NG_FREE_NODE(node) \ 343 do { \ 344 mtx_lock(&ng_nodelist_mtx); \ 345 LIST_INSERT_HEAD(&ng_freenodes, node, nd_nodes); \ 346 node->nd_magic = 0; \ 347 mtx_unlock(&ng_nodelist_mtx); \ 348 } while (0) 349 350 #else /* NETGRAPH_DEBUG */ /*----------------------------------------------*/ 351 352 #define NG_ALLOC_HOOK(hook) _NG_ALLOC_HOOK(hook) 353 #define NG_ALLOC_NODE(node) _NG_ALLOC_NODE(node) 354 355 #define NG_FREE_HOOK(hook) do { free((hook), M_NETGRAPH_HOOK); } while (0) 356 #define NG_FREE_NODE(node) do { free((node), M_NETGRAPH_NODE); } while (0) 357 358 #endif /* NETGRAPH_DEBUG */ /*----------------------------------------------*/ 359 360 /* Set this to kdb_enter("X") to catch all errors as they occur */ 361 #ifndef TRAP_ERROR 362 #define TRAP_ERROR() 363 #endif 364 365 static VNET_DEFINE(ng_ID_t, nextID) = 1; 366 #define V_nextID VNET(nextID) 367 368 #ifdef INVARIANTS 369 #define CHECK_DATA_MBUF(m) do { \ 370 struct mbuf *n; \ 371 int total; \ 372 \ 373 M_ASSERTPKTHDR(m); \ 374 for (total = 0, n = (m); n != NULL; n = n->m_next) { \ 375 total += n->m_len; \ 376 if (n->m_nextpkt != NULL) \ 377 panic("%s: m_nextpkt", __func__); \ 378 } \ 379 \ 380 if ((m)->m_pkthdr.len != total) { \ 381 panic("%s: %d != %d", \ 382 __func__, (m)->m_pkthdr.len, total); \ 383 } \ 384 } while (0) 385 #else 386 #define CHECK_DATA_MBUF(m) 387 #endif 388 389 #define ERROUT(x) do { error = (x); goto done; } while (0) 390 391 /************************************************************************ 392 Parse type definitions for generic messages 393 ************************************************************************/ 394 395 /* Handy structure parse type defining macro */ 396 #define DEFINE_PARSE_STRUCT_TYPE(lo, up, args) \ 397 static const struct ng_parse_struct_field \ 398 ng_ ## lo ## _type_fields[] = NG_GENERIC_ ## up ## _INFO args; \ 399 static const struct ng_parse_type ng_generic_ ## lo ## _type = { \ 400 &ng_parse_struct_type, \ 401 &ng_ ## lo ## _type_fields \ 402 } 403 404 DEFINE_PARSE_STRUCT_TYPE(mkpeer, MKPEER, ()); 405 DEFINE_PARSE_STRUCT_TYPE(connect, CONNECT, ()); 406 DEFINE_PARSE_STRUCT_TYPE(name, NAME, ()); 407 DEFINE_PARSE_STRUCT_TYPE(rmhook, RMHOOK, ()); 408 DEFINE_PARSE_STRUCT_TYPE(nodeinfo, NODEINFO, ()); 409 DEFINE_PARSE_STRUCT_TYPE(typeinfo, TYPEINFO, ()); 410 DEFINE_PARSE_STRUCT_TYPE(linkinfo, LINKINFO, (&ng_generic_nodeinfo_type)); 411 412 /* Get length of an array when the length is stored as a 32 bit 413 value immediately preceding the array -- as with struct namelist 414 and struct typelist. */ 415 static int 416 ng_generic_list_getLength(const struct ng_parse_type *type, 417 const u_char *start, const u_char *buf) 418 { 419 return *((const u_int32_t *)(buf - 4)); 420 } 421 422 /* Get length of the array of struct linkinfo inside a struct hooklist */ 423 static int 424 ng_generic_linkinfo_getLength(const struct ng_parse_type *type, 425 const u_char *start, const u_char *buf) 426 { 427 const struct hooklist *hl = (const struct hooklist *)start; 428 429 return hl->nodeinfo.hooks; 430 } 431 432 /* Array type for a variable length array of struct namelist */ 433 static const struct ng_parse_array_info ng_nodeinfoarray_type_info = { 434 &ng_generic_nodeinfo_type, 435 &ng_generic_list_getLength 436 }; 437 static const struct ng_parse_type ng_generic_nodeinfoarray_type = { 438 &ng_parse_array_type, 439 &ng_nodeinfoarray_type_info 440 }; 441 442 /* Array type for a variable length array of struct typelist */ 443 static const struct ng_parse_array_info ng_typeinfoarray_type_info = { 444 &ng_generic_typeinfo_type, 445 &ng_generic_list_getLength 446 }; 447 static const struct ng_parse_type ng_generic_typeinfoarray_type = { 448 &ng_parse_array_type, 449 &ng_typeinfoarray_type_info 450 }; 451 452 /* Array type for array of struct linkinfo in struct hooklist */ 453 static const struct ng_parse_array_info ng_generic_linkinfo_array_type_info = { 454 &ng_generic_linkinfo_type, 455 &ng_generic_linkinfo_getLength 456 }; 457 static const struct ng_parse_type ng_generic_linkinfo_array_type = { 458 &ng_parse_array_type, 459 &ng_generic_linkinfo_array_type_info 460 }; 461 462 DEFINE_PARSE_STRUCT_TYPE(typelist, TYPELIST, (&ng_generic_nodeinfoarray_type)); 463 DEFINE_PARSE_STRUCT_TYPE(hooklist, HOOKLIST, 464 (&ng_generic_nodeinfo_type, &ng_generic_linkinfo_array_type)); 465 DEFINE_PARSE_STRUCT_TYPE(listnodes, LISTNODES, 466 (&ng_generic_nodeinfoarray_type)); 467 468 /* List of commands and how to convert arguments to/from ASCII */ 469 static const struct ng_cmdlist ng_generic_cmds[] = { 470 { 471 NGM_GENERIC_COOKIE, 472 NGM_SHUTDOWN, 473 "shutdown", 474 NULL, 475 NULL 476 }, 477 { 478 NGM_GENERIC_COOKIE, 479 NGM_MKPEER, 480 "mkpeer", 481 &ng_generic_mkpeer_type, 482 NULL 483 }, 484 { 485 NGM_GENERIC_COOKIE, 486 NGM_CONNECT, 487 "connect", 488 &ng_generic_connect_type, 489 NULL 490 }, 491 { 492 NGM_GENERIC_COOKIE, 493 NGM_NAME, 494 "name", 495 &ng_generic_name_type, 496 NULL 497 }, 498 { 499 NGM_GENERIC_COOKIE, 500 NGM_RMHOOK, 501 "rmhook", 502 &ng_generic_rmhook_type, 503 NULL 504 }, 505 { 506 NGM_GENERIC_COOKIE, 507 NGM_NODEINFO, 508 "nodeinfo", 509 NULL, 510 &ng_generic_nodeinfo_type 511 }, 512 { 513 NGM_GENERIC_COOKIE, 514 NGM_LISTHOOKS, 515 "listhooks", 516 NULL, 517 &ng_generic_hooklist_type 518 }, 519 { 520 NGM_GENERIC_COOKIE, 521 NGM_LISTNAMES, 522 "listnames", 523 NULL, 524 &ng_generic_listnodes_type /* same as NGM_LISTNODES */ 525 }, 526 { 527 NGM_GENERIC_COOKIE, 528 NGM_LISTNODES, 529 "listnodes", 530 NULL, 531 &ng_generic_listnodes_type 532 }, 533 { 534 NGM_GENERIC_COOKIE, 535 NGM_LISTTYPES, 536 "listtypes", 537 NULL, 538 &ng_generic_typeinfo_type 539 }, 540 { 541 NGM_GENERIC_COOKIE, 542 NGM_TEXT_CONFIG, 543 "textconfig", 544 NULL, 545 &ng_parse_string_type 546 }, 547 { 548 NGM_GENERIC_COOKIE, 549 NGM_TEXT_STATUS, 550 "textstatus", 551 NULL, 552 &ng_parse_string_type 553 }, 554 { 555 NGM_GENERIC_COOKIE, 556 NGM_ASCII2BINARY, 557 "ascii2binary", 558 &ng_parse_ng_mesg_type, 559 &ng_parse_ng_mesg_type 560 }, 561 { 562 NGM_GENERIC_COOKIE, 563 NGM_BINARY2ASCII, 564 "binary2ascii", 565 &ng_parse_ng_mesg_type, 566 &ng_parse_ng_mesg_type 567 }, 568 { 0 } 569 }; 570 571 /************************************************************************ 572 Node routines 573 ************************************************************************/ 574 575 /* 576 * Instantiate a node of the requested type 577 */ 578 int 579 ng_make_node(const char *typename, node_p *nodepp) 580 { 581 struct ng_type *type; 582 int error; 583 584 /* Check that the type makes sense */ 585 if (typename == NULL) { 586 TRAP_ERROR(); 587 return (EINVAL); 588 } 589 590 /* Locate the node type. If we fail we return. Do not try to load 591 * module. 592 */ 593 if ((type = ng_findtype(typename)) == NULL) 594 return (ENXIO); 595 596 /* 597 * If we have a constructor, then make the node and 598 * call the constructor to do type specific initialisation. 599 */ 600 if (type->constructor != NULL) { 601 if ((error = ng_make_node_common(type, nodepp)) == 0) { 602 if ((error = ((*type->constructor)(*nodepp))) != 0) { 603 NG_NODE_UNREF(*nodepp); 604 } 605 } 606 } else { 607 /* 608 * Node has no constructor. We cannot ask for one 609 * to be made. It must be brought into existence by 610 * some external agency. The external agency should 611 * call ng_make_node_common() directly to get the 612 * netgraph part initialised. 613 */ 614 TRAP_ERROR(); 615 error = EINVAL; 616 } 617 return (error); 618 } 619 620 /* 621 * Generic node creation. Called by node initialisation for externally 622 * instantiated nodes (e.g. hardware, sockets, etc ). 623 * The returned node has a reference count of 1. 624 */ 625 int 626 ng_make_node_common(struct ng_type *type, node_p *nodepp) 627 { 628 node_p node; 629 630 /* Require the node type to have been already installed */ 631 if (ng_findtype(type->name) == NULL) { 632 TRAP_ERROR(); 633 return (EINVAL); 634 } 635 636 /* Make a node and try attach it to the type */ 637 NG_ALLOC_NODE(node); 638 if (node == NULL) { 639 TRAP_ERROR(); 640 return (ENOMEM); 641 } 642 node->nd_type = type; 643 #ifdef VIMAGE 644 node->nd_vnet = curvnet; 645 #endif 646 NG_NODE_REF(node); /* note reference */ 647 type->refs++; 648 649 NG_QUEUE_LOCK_INIT(&node->nd_input_queue); 650 STAILQ_INIT(&node->nd_input_queue.queue); 651 node->nd_input_queue.q_flags = 0; 652 653 /* Initialize hook list for new node */ 654 LIST_INIT(&node->nd_hooks); 655 656 /* Link us into the name hash. */ 657 mtx_lock(&ng_namehash_mtx); 658 LIST_INSERT_HEAD(&V_ng_name_hash[0], node, nd_nodes); 659 mtx_unlock(&ng_namehash_mtx); 660 661 /* get an ID and put us in the hash chain */ 662 mtx_lock(&ng_idhash_mtx); 663 for (;;) { /* wrap protection, even if silly */ 664 node_p node2 = NULL; 665 node->nd_ID = V_nextID++; /* 137/sec for 1 year before wrap */ 666 667 /* Is there a problem with the new number? */ 668 NG_IDHASH_FIND(node->nd_ID, node2); /* already taken? */ 669 if ((node->nd_ID != 0) && (node2 == NULL)) { 670 break; 671 } 672 } 673 LIST_INSERT_HEAD(&V_ng_ID_hash[NG_IDHASH_FN(node->nd_ID)], 674 node, nd_idnodes); 675 mtx_unlock(&ng_idhash_mtx); 676 677 /* Done */ 678 *nodepp = node; 679 return (0); 680 } 681 682 /* 683 * Forceably start the shutdown process on a node. Either call 684 * its shutdown method, or do the default shutdown if there is 685 * no type-specific method. 686 * 687 * We can only be called from a shutdown message, so we know we have 688 * a writer lock, and therefore exclusive access. It also means 689 * that we should not be on the work queue, but we check anyhow. 690 * 691 * Persistent node types must have a type-specific method which 692 * allocates a new node in which case, this one is irretrievably going away, 693 * or cleans up anything it needs, and just makes the node valid again, 694 * in which case we allow the node to survive. 695 * 696 * XXX We need to think of how to tell a persistent node that we 697 * REALLY need to go away because the hardware has gone or we 698 * are rebooting.... etc. 699 */ 700 void 701 ng_rmnode(node_p node, hook_p dummy1, void *dummy2, int dummy3) 702 { 703 hook_p hook; 704 705 /* Check if it's already shutting down */ 706 if ((node->nd_flags & NGF_CLOSING) != 0) 707 return; 708 709 if (node == &ng_deadnode) { 710 printf ("shutdown called on deadnode\n"); 711 return; 712 } 713 714 /* Add an extra reference so it doesn't go away during this */ 715 NG_NODE_REF(node); 716 717 /* 718 * Mark it invalid so any newcomers know not to try use it 719 * Also add our own mark so we can't recurse 720 * note that NGF_INVALID does not do this as it's also set during 721 * creation 722 */ 723 node->nd_flags |= NGF_INVALID|NGF_CLOSING; 724 725 /* If node has its pre-shutdown method, then call it first*/ 726 if (node->nd_type && node->nd_type->close) 727 (*node->nd_type->close)(node); 728 729 /* Notify all remaining connected nodes to disconnect */ 730 while ((hook = LIST_FIRST(&node->nd_hooks)) != NULL) 731 ng_destroy_hook(hook); 732 733 /* 734 * Drain the input queue forceably. 735 * it has no hooks so what's it going to do, bleed on someone? 736 * Theoretically we came here from a queue entry that was added 737 * Just before the queue was closed, so it should be empty anyway. 738 * Also removes us from worklist if needed. 739 */ 740 ng_flush_input_queue(node); 741 742 /* Ask the type if it has anything to do in this case */ 743 if (node->nd_type && node->nd_type->shutdown) { 744 (*node->nd_type->shutdown)(node); 745 if (NG_NODE_IS_VALID(node)) { 746 /* 747 * Well, blow me down if the node code hasn't declared 748 * that it doesn't want to die. 749 * Presumably it is a persistant node. 750 * If we REALLY want it to go away, 751 * e.g. hardware going away, 752 * Our caller should set NGF_REALLY_DIE in nd_flags. 753 */ 754 node->nd_flags &= ~(NGF_INVALID|NGF_CLOSING); 755 NG_NODE_UNREF(node); /* Assume they still have theirs */ 756 return; 757 } 758 } else { /* do the default thing */ 759 NG_NODE_UNREF(node); 760 } 761 762 ng_unname(node); /* basically a NOP these days */ 763 764 /* 765 * Remove extra reference, possibly the last 766 * Possible other holders of references may include 767 * timeout callouts, but theoretically the node's supposed to 768 * have cancelled them. Possibly hardware dependencies may 769 * force a driver to 'linger' with a reference. 770 */ 771 NG_NODE_UNREF(node); 772 } 773 774 /* 775 * Remove a reference to the node, possibly the last. 776 * deadnode always acts as it it were the last. 777 */ 778 void 779 ng_unref_node(node_p node) 780 { 781 782 if (node == &ng_deadnode) 783 return; 784 785 if (refcount_release(&node->nd_refs)) { /* we were the last */ 786 787 mtx_lock(&ng_namehash_mtx); 788 node->nd_type->refs--; /* XXX maybe should get types lock? */ 789 LIST_REMOVE(node, nd_nodes); 790 mtx_unlock(&ng_namehash_mtx); 791 792 mtx_lock(&ng_idhash_mtx); 793 LIST_REMOVE(node, nd_idnodes); 794 mtx_unlock(&ng_idhash_mtx); 795 796 mtx_destroy(&node->nd_input_queue.q_mtx); 797 NG_FREE_NODE(node); 798 } 799 } 800 801 /************************************************************************ 802 Node ID handling 803 ************************************************************************/ 804 static node_p 805 ng_ID2noderef(ng_ID_t ID) 806 { 807 node_p node; 808 mtx_lock(&ng_idhash_mtx); 809 NG_IDHASH_FIND(ID, node); 810 if(node) 811 NG_NODE_REF(node); 812 mtx_unlock(&ng_idhash_mtx); 813 return(node); 814 } 815 816 ng_ID_t 817 ng_node2ID(node_p node) 818 { 819 return (node ? NG_NODE_ID(node) : 0); 820 } 821 822 /************************************************************************ 823 Node name handling 824 ************************************************************************/ 825 826 /* 827 * Assign a node a name. Once assigned, the name cannot be changed. 828 */ 829 int 830 ng_name_node(node_p node, const char *name) 831 { 832 int i, hash; 833 node_p node2; 834 835 /* Check the name is valid */ 836 for (i = 0; i < NG_NODESIZ; i++) { 837 if (name[i] == '\0' || name[i] == '.' || name[i] == ':') 838 break; 839 } 840 if (i == 0 || name[i] != '\0') { 841 TRAP_ERROR(); 842 return (EINVAL); 843 } 844 if (ng_decodeidname(name) != 0) { /* valid IDs not allowed here */ 845 TRAP_ERROR(); 846 return (EINVAL); 847 } 848 849 /* Check the name isn't already being used */ 850 if ((node2 = ng_name2noderef(node, name)) != NULL) { 851 NG_NODE_UNREF(node2); 852 TRAP_ERROR(); 853 return (EADDRINUSE); 854 } 855 856 /* copy it */ 857 strlcpy(NG_NODE_NAME(node), name, NG_NODESIZ); 858 859 /* Update name hash. */ 860 NG_NAMEHASH(name, hash); 861 mtx_lock(&ng_namehash_mtx); 862 LIST_REMOVE(node, nd_nodes); 863 LIST_INSERT_HEAD(&V_ng_name_hash[hash], node, nd_nodes); 864 mtx_unlock(&ng_namehash_mtx); 865 866 return (0); 867 } 868 869 /* 870 * Find a node by absolute name. The name should NOT end with ':' 871 * The name "." means "this node" and "[xxx]" means "the node 872 * with ID (ie, at address) xxx". 873 * 874 * Returns the node if found, else NULL. 875 * Eventually should add something faster than a sequential search. 876 * Note it acquires a reference on the node so you can be sure it's still 877 * there. 878 */ 879 node_p 880 ng_name2noderef(node_p here, const char *name) 881 { 882 node_p node; 883 ng_ID_t temp; 884 int hash; 885 886 /* "." means "this node" */ 887 if (strcmp(name, ".") == 0) { 888 NG_NODE_REF(here); 889 return(here); 890 } 891 892 /* Check for name-by-ID */ 893 if ((temp = ng_decodeidname(name)) != 0) { 894 return (ng_ID2noderef(temp)); 895 } 896 897 /* Find node by name */ 898 NG_NAMEHASH(name, hash); 899 mtx_lock(&ng_namehash_mtx); 900 LIST_FOREACH(node, &V_ng_name_hash[hash], nd_nodes) { 901 if (NG_NODE_IS_VALID(node) && 902 (strcmp(NG_NODE_NAME(node), name) == 0)) { 903 break; 904 } 905 } 906 if (node) 907 NG_NODE_REF(node); 908 mtx_unlock(&ng_namehash_mtx); 909 return (node); 910 } 911 912 /* 913 * Decode an ID name, eg. "[f03034de]". Returns 0 if the 914 * string is not valid, otherwise returns the value. 915 */ 916 static ng_ID_t 917 ng_decodeidname(const char *name) 918 { 919 const int len = strlen(name); 920 char *eptr; 921 u_long val; 922 923 /* Check for proper length, brackets, no leading junk */ 924 if ((len < 3) 925 || (name[0] != '[') 926 || (name[len - 1] != ']') 927 || (!isxdigit(name[1]))) { 928 return ((ng_ID_t)0); 929 } 930 931 /* Decode number */ 932 val = strtoul(name + 1, &eptr, 16); 933 if ((eptr - name != len - 1) 934 || (val == ULONG_MAX) 935 || (val == 0)) { 936 return ((ng_ID_t)0); 937 } 938 return (ng_ID_t)val; 939 } 940 941 /* 942 * Remove a name from a node. This should only be called 943 * when shutting down and removing the node. 944 * IF we allow name changing this may be more resurrected. 945 */ 946 void 947 ng_unname(node_p node) 948 { 949 } 950 951 /************************************************************************ 952 Hook routines 953 Names are not optional. Hooks are always connected, except for a 954 brief moment within these routines. On invalidation or during creation 955 they are connected to the 'dead' hook. 956 ************************************************************************/ 957 958 /* 959 * Remove a hook reference 960 */ 961 void 962 ng_unref_hook(hook_p hook) 963 { 964 965 if (hook == &ng_deadhook) 966 return; 967 968 if (refcount_release(&hook->hk_refs)) { /* we were the last */ 969 if (_NG_HOOK_NODE(hook)) /* it'll probably be ng_deadnode */ 970 _NG_NODE_UNREF((_NG_HOOK_NODE(hook))); 971 NG_FREE_HOOK(hook); 972 } 973 } 974 975 /* 976 * Add an unconnected hook to a node. Only used internally. 977 * Assumes node is locked. (XXX not yet true ) 978 */ 979 static int 980 ng_add_hook(node_p node, const char *name, hook_p *hookp) 981 { 982 hook_p hook; 983 int error = 0; 984 985 /* Check that the given name is good */ 986 if (name == NULL) { 987 TRAP_ERROR(); 988 return (EINVAL); 989 } 990 if (ng_findhook(node, name) != NULL) { 991 TRAP_ERROR(); 992 return (EEXIST); 993 } 994 995 /* Allocate the hook and link it up */ 996 NG_ALLOC_HOOK(hook); 997 if (hook == NULL) { 998 TRAP_ERROR(); 999 return (ENOMEM); 1000 } 1001 hook->hk_refs = 1; /* add a reference for us to return */ 1002 hook->hk_flags = HK_INVALID; 1003 hook->hk_peer = &ng_deadhook; /* start off this way */ 1004 hook->hk_node = node; 1005 NG_NODE_REF(node); /* each hook counts as a reference */ 1006 1007 /* Set hook name */ 1008 strlcpy(NG_HOOK_NAME(hook), name, NG_HOOKSIZ); 1009 1010 /* 1011 * Check if the node type code has something to say about it 1012 * If it fails, the unref of the hook will also unref the node. 1013 */ 1014 if (node->nd_type->newhook != NULL) { 1015 if ((error = (*node->nd_type->newhook)(node, hook, name))) { 1016 NG_HOOK_UNREF(hook); /* this frees the hook */ 1017 return (error); 1018 } 1019 } 1020 /* 1021 * The 'type' agrees so far, so go ahead and link it in. 1022 * We'll ask again later when we actually connect the hooks. 1023 */ 1024 LIST_INSERT_HEAD(&node->nd_hooks, hook, hk_hooks); 1025 node->nd_numhooks++; 1026 NG_HOOK_REF(hook); /* one for the node */ 1027 1028 if (hookp) 1029 *hookp = hook; 1030 return (0); 1031 } 1032 1033 /* 1034 * Find a hook 1035 * 1036 * Node types may supply their own optimized routines for finding 1037 * hooks. If none is supplied, we just do a linear search. 1038 * XXX Possibly we should add a reference to the hook? 1039 */ 1040 hook_p 1041 ng_findhook(node_p node, const char *name) 1042 { 1043 hook_p hook; 1044 1045 if (node->nd_type->findhook != NULL) 1046 return (*node->nd_type->findhook)(node, name); 1047 LIST_FOREACH(hook, &node->nd_hooks, hk_hooks) { 1048 if (NG_HOOK_IS_VALID(hook) 1049 && (strcmp(NG_HOOK_NAME(hook), name) == 0)) 1050 return (hook); 1051 } 1052 return (NULL); 1053 } 1054 1055 /* 1056 * Destroy a hook 1057 * 1058 * As hooks are always attached, this really destroys two hooks. 1059 * The one given, and the one attached to it. Disconnect the hooks 1060 * from each other first. We reconnect the peer hook to the 'dead' 1061 * hook so that it can still exist after we depart. We then 1062 * send the peer its own destroy message. This ensures that we only 1063 * interact with the peer's structures when it is locked processing that 1064 * message. We hold a reference to the peer hook so we are guaranteed that 1065 * the peer hook and node are still going to exist until 1066 * we are finished there as the hook holds a ref on the node. 1067 * We run this same code again on the peer hook, but that time it is already 1068 * attached to the 'dead' hook. 1069 * 1070 * This routine is called at all stages of hook creation 1071 * on error detection and must be able to handle any such stage. 1072 */ 1073 void 1074 ng_destroy_hook(hook_p hook) 1075 { 1076 hook_p peer; 1077 node_p node; 1078 1079 if (hook == &ng_deadhook) { /* better safe than sorry */ 1080 printf("ng_destroy_hook called on deadhook\n"); 1081 return; 1082 } 1083 1084 /* 1085 * Protect divorce process with mutex, to avoid races on 1086 * simultaneous disconnect. 1087 */ 1088 mtx_lock(&ng_topo_mtx); 1089 1090 hook->hk_flags |= HK_INVALID; 1091 1092 peer = NG_HOOK_PEER(hook); 1093 node = NG_HOOK_NODE(hook); 1094 1095 if (peer && (peer != &ng_deadhook)) { 1096 /* 1097 * Set the peer to point to ng_deadhook 1098 * from this moment on we are effectively independent it. 1099 * send it an rmhook message of it's own. 1100 */ 1101 peer->hk_peer = &ng_deadhook; /* They no longer know us */ 1102 hook->hk_peer = &ng_deadhook; /* Nor us, them */ 1103 if (NG_HOOK_NODE(peer) == &ng_deadnode) { 1104 /* 1105 * If it's already divorced from a node, 1106 * just free it. 1107 */ 1108 mtx_unlock(&ng_topo_mtx); 1109 } else { 1110 mtx_unlock(&ng_topo_mtx); 1111 ng_rmhook_self(peer); /* Send it a surprise */ 1112 } 1113 NG_HOOK_UNREF(peer); /* account for peer link */ 1114 NG_HOOK_UNREF(hook); /* account for peer link */ 1115 } else 1116 mtx_unlock(&ng_topo_mtx); 1117 1118 mtx_assert(&ng_topo_mtx, MA_NOTOWNED); 1119 1120 /* 1121 * Remove the hook from the node's list to avoid possible recursion 1122 * in case the disconnection results in node shutdown. 1123 */ 1124 if (node == &ng_deadnode) { /* happens if called from ng_con_nodes() */ 1125 return; 1126 } 1127 LIST_REMOVE(hook, hk_hooks); 1128 node->nd_numhooks--; 1129 if (node->nd_type->disconnect) { 1130 /* 1131 * The type handler may elect to destroy the node so don't 1132 * trust its existence after this point. (except 1133 * that we still hold a reference on it. (which we 1134 * inherrited from the hook we are destroying) 1135 */ 1136 (*node->nd_type->disconnect) (hook); 1137 } 1138 1139 /* 1140 * Note that because we will point to ng_deadnode, the original node 1141 * is not decremented automatically so we do that manually. 1142 */ 1143 _NG_HOOK_NODE(hook) = &ng_deadnode; 1144 NG_NODE_UNREF(node); /* We no longer point to it so adjust count */ 1145 NG_HOOK_UNREF(hook); /* Account for linkage (in list) to node */ 1146 } 1147 1148 /* 1149 * Take two hooks on a node and merge the connection so that the given node 1150 * is effectively bypassed. 1151 */ 1152 int 1153 ng_bypass(hook_p hook1, hook_p hook2) 1154 { 1155 if (hook1->hk_node != hook2->hk_node) { 1156 TRAP_ERROR(); 1157 return (EINVAL); 1158 } 1159 mtx_lock(&ng_topo_mtx); 1160 hook1->hk_peer->hk_peer = hook2->hk_peer; 1161 hook2->hk_peer->hk_peer = hook1->hk_peer; 1162 1163 hook1->hk_peer = &ng_deadhook; 1164 hook2->hk_peer = &ng_deadhook; 1165 mtx_unlock(&ng_topo_mtx); 1166 1167 NG_HOOK_UNREF(hook1); 1168 NG_HOOK_UNREF(hook2); 1169 1170 /* XXX If we ever cache methods on hooks update them as well */ 1171 ng_destroy_hook(hook1); 1172 ng_destroy_hook(hook2); 1173 return (0); 1174 } 1175 1176 /* 1177 * Install a new netgraph type 1178 */ 1179 int 1180 ng_newtype(struct ng_type *tp) 1181 { 1182 const size_t namelen = strlen(tp->name); 1183 1184 /* Check version and type name fields */ 1185 if ((tp->version != NG_ABI_VERSION) 1186 || (namelen == 0) 1187 || (namelen >= NG_TYPESIZ)) { 1188 TRAP_ERROR(); 1189 if (tp->version != NG_ABI_VERSION) { 1190 printf("Netgraph: Node type rejected. ABI mismatch. Suggest recompile\n"); 1191 } 1192 return (EINVAL); 1193 } 1194 1195 /* Check for name collision */ 1196 if (ng_findtype(tp->name) != NULL) { 1197 TRAP_ERROR(); 1198 return (EEXIST); 1199 } 1200 1201 1202 /* Link in new type */ 1203 mtx_lock(&ng_typelist_mtx); 1204 LIST_INSERT_HEAD(&ng_typelist, tp, types); 1205 tp->refs = 1; /* first ref is linked list */ 1206 mtx_unlock(&ng_typelist_mtx); 1207 return (0); 1208 } 1209 1210 /* 1211 * unlink a netgraph type 1212 * If no examples exist 1213 */ 1214 int 1215 ng_rmtype(struct ng_type *tp) 1216 { 1217 /* Check for name collision */ 1218 if (tp->refs != 1) { 1219 TRAP_ERROR(); 1220 return (EBUSY); 1221 } 1222 1223 /* Unlink type */ 1224 mtx_lock(&ng_typelist_mtx); 1225 LIST_REMOVE(tp, types); 1226 mtx_unlock(&ng_typelist_mtx); 1227 return (0); 1228 } 1229 1230 /* 1231 * Look for a type of the name given 1232 */ 1233 struct ng_type * 1234 ng_findtype(const char *typename) 1235 { 1236 struct ng_type *type; 1237 1238 mtx_lock(&ng_typelist_mtx); 1239 LIST_FOREACH(type, &ng_typelist, types) { 1240 if (strcmp(type->name, typename) == 0) 1241 break; 1242 } 1243 mtx_unlock(&ng_typelist_mtx); 1244 return (type); 1245 } 1246 1247 /************************************************************************ 1248 Composite routines 1249 ************************************************************************/ 1250 /* 1251 * Connect two nodes using the specified hooks, using queued functions. 1252 */ 1253 static int 1254 ng_con_part3(node_p node, item_p item, hook_p hook) 1255 { 1256 int error = 0; 1257 1258 /* 1259 * When we run, we know that the node 'node' is locked for us. 1260 * Our caller has a reference on the hook. 1261 * Our caller has a reference on the node. 1262 * (In this case our caller is ng_apply_item() ). 1263 * The peer hook has a reference on the hook. 1264 * We are all set up except for the final call to the node, and 1265 * the clearing of the INVALID flag. 1266 */ 1267 if (NG_HOOK_NODE(hook) == &ng_deadnode) { 1268 /* 1269 * The node must have been freed again since we last visited 1270 * here. ng_destry_hook() has this effect but nothing else does. 1271 * We should just release our references and 1272 * free anything we can think of. 1273 * Since we know it's been destroyed, and it's our caller 1274 * that holds the references, just return. 1275 */ 1276 ERROUT(ENOENT); 1277 } 1278 if (hook->hk_node->nd_type->connect) { 1279 if ((error = (*hook->hk_node->nd_type->connect) (hook))) { 1280 ng_destroy_hook(hook); /* also zaps peer */ 1281 printf("failed in ng_con_part3()\n"); 1282 ERROUT(error); 1283 } 1284 } 1285 /* 1286 * XXX this is wrong for SMP. Possibly we need 1287 * to separate out 'create' and 'invalid' flags. 1288 * should only set flags on hooks we have locked under our node. 1289 */ 1290 hook->hk_flags &= ~HK_INVALID; 1291 done: 1292 NG_FREE_ITEM(item); 1293 return (error); 1294 } 1295 1296 static int 1297 ng_con_part2(node_p node, item_p item, hook_p hook) 1298 { 1299 hook_p peer; 1300 int error = 0; 1301 1302 /* 1303 * When we run, we know that the node 'node' is locked for us. 1304 * Our caller has a reference on the hook. 1305 * Our caller has a reference on the node. 1306 * (In this case our caller is ng_apply_item() ). 1307 * The peer hook has a reference on the hook. 1308 * our node pointer points to the 'dead' node. 1309 * First check the hook name is unique. 1310 * Should not happen because we checked before queueing this. 1311 */ 1312 if (ng_findhook(node, NG_HOOK_NAME(hook)) != NULL) { 1313 TRAP_ERROR(); 1314 ng_destroy_hook(hook); /* should destroy peer too */ 1315 printf("failed in ng_con_part2()\n"); 1316 ERROUT(EEXIST); 1317 } 1318 /* 1319 * Check if the node type code has something to say about it 1320 * If it fails, the unref of the hook will also unref the attached node, 1321 * however since that node is 'ng_deadnode' this will do nothing. 1322 * The peer hook will also be destroyed. 1323 */ 1324 if (node->nd_type->newhook != NULL) { 1325 if ((error = (*node->nd_type->newhook)(node, hook, 1326 hook->hk_name))) { 1327 ng_destroy_hook(hook); /* should destroy peer too */ 1328 printf("failed in ng_con_part2()\n"); 1329 ERROUT(error); 1330 } 1331 } 1332 1333 /* 1334 * The 'type' agrees so far, so go ahead and link it in. 1335 * We'll ask again later when we actually connect the hooks. 1336 */ 1337 hook->hk_node = node; /* just overwrite ng_deadnode */ 1338 NG_NODE_REF(node); /* each hook counts as a reference */ 1339 LIST_INSERT_HEAD(&node->nd_hooks, hook, hk_hooks); 1340 node->nd_numhooks++; 1341 NG_HOOK_REF(hook); /* one for the node */ 1342 1343 /* 1344 * We now have a symmetrical situation, where both hooks have been 1345 * linked to their nodes, the newhook methods have been called 1346 * And the references are all correct. The hooks are still marked 1347 * as invalid, as we have not called the 'connect' methods 1348 * yet. 1349 * We can call the local one immediately as we have the 1350 * node locked, but we need to queue the remote one. 1351 */ 1352 if (hook->hk_node->nd_type->connect) { 1353 if ((error = (*hook->hk_node->nd_type->connect) (hook))) { 1354 ng_destroy_hook(hook); /* also zaps peer */ 1355 printf("failed in ng_con_part2(A)\n"); 1356 ERROUT(error); 1357 } 1358 } 1359 1360 /* 1361 * Acquire topo mutex to avoid race with ng_destroy_hook(). 1362 */ 1363 mtx_lock(&ng_topo_mtx); 1364 peer = hook->hk_peer; 1365 if (peer == &ng_deadhook) { 1366 mtx_unlock(&ng_topo_mtx); 1367 printf("failed in ng_con_part2(B)\n"); 1368 ng_destroy_hook(hook); 1369 ERROUT(ENOENT); 1370 } 1371 mtx_unlock(&ng_topo_mtx); 1372 1373 if ((error = ng_send_fn2(peer->hk_node, peer, item, &ng_con_part3, 1374 NULL, 0, NG_REUSE_ITEM))) { 1375 printf("failed in ng_con_part2(C)\n"); 1376 ng_destroy_hook(hook); /* also zaps peer */ 1377 return (error); /* item was consumed. */ 1378 } 1379 hook->hk_flags &= ~HK_INVALID; /* need both to be able to work */ 1380 return (0); /* item was consumed. */ 1381 done: 1382 NG_FREE_ITEM(item); 1383 return (error); 1384 } 1385 1386 /* 1387 * Connect this node with another node. We assume that this node is 1388 * currently locked, as we are only called from an NGM_CONNECT message. 1389 */ 1390 static int 1391 ng_con_nodes(item_p item, node_p node, const char *name, 1392 node_p node2, const char *name2) 1393 { 1394 int error; 1395 hook_p hook; 1396 hook_p hook2; 1397 1398 if (ng_findhook(node2, name2) != NULL) { 1399 return(EEXIST); 1400 } 1401 if ((error = ng_add_hook(node, name, &hook))) /* gives us a ref */ 1402 return (error); 1403 /* Allocate the other hook and link it up */ 1404 NG_ALLOC_HOOK(hook2); 1405 if (hook2 == NULL) { 1406 TRAP_ERROR(); 1407 ng_destroy_hook(hook); /* XXX check ref counts so far */ 1408 NG_HOOK_UNREF(hook); /* including our ref */ 1409 return (ENOMEM); 1410 } 1411 hook2->hk_refs = 1; /* start with a reference for us. */ 1412 hook2->hk_flags = HK_INVALID; 1413 hook2->hk_peer = hook; /* Link the two together */ 1414 hook->hk_peer = hook2; 1415 NG_HOOK_REF(hook); /* Add a ref for the peer to each*/ 1416 NG_HOOK_REF(hook2); 1417 hook2->hk_node = &ng_deadnode; 1418 strlcpy(NG_HOOK_NAME(hook2), name2, NG_HOOKSIZ); 1419 1420 /* 1421 * Queue the function above. 1422 * Procesing continues in that function in the lock context of 1423 * the other node. 1424 */ 1425 if ((error = ng_send_fn2(node2, hook2, item, &ng_con_part2, NULL, 0, 1426 NG_NOFLAGS))) { 1427 printf("failed in ng_con_nodes(): %d\n", error); 1428 ng_destroy_hook(hook); /* also zaps peer */ 1429 } 1430 1431 NG_HOOK_UNREF(hook); /* Let each hook go if it wants to */ 1432 NG_HOOK_UNREF(hook2); 1433 return (error); 1434 } 1435 1436 /* 1437 * Make a peer and connect. 1438 * We assume that the local node is locked. 1439 * The new node probably doesn't need a lock until 1440 * it has a hook, because it cannot really have any work until then, 1441 * but we should think about it a bit more. 1442 * 1443 * The problem may come if the other node also fires up 1444 * some hardware or a timer or some other source of activation, 1445 * also it may already get a command msg via it's ID. 1446 * 1447 * We could use the same method as ng_con_nodes() but we'd have 1448 * to add ability to remove the node when failing. (Not hard, just 1449 * make arg1 point to the node to remove). 1450 * Unless of course we just ignore failure to connect and leave 1451 * an unconnected node? 1452 */ 1453 static int 1454 ng_mkpeer(node_p node, const char *name, const char *name2, char *type) 1455 { 1456 node_p node2; 1457 hook_p hook1, hook2; 1458 int error; 1459 1460 if ((error = ng_make_node(type, &node2))) { 1461 return (error); 1462 } 1463 1464 if ((error = ng_add_hook(node, name, &hook1))) { /* gives us a ref */ 1465 ng_rmnode(node2, NULL, NULL, 0); 1466 return (error); 1467 } 1468 1469 if ((error = ng_add_hook(node2, name2, &hook2))) { 1470 ng_rmnode(node2, NULL, NULL, 0); 1471 ng_destroy_hook(hook1); 1472 NG_HOOK_UNREF(hook1); 1473 return (error); 1474 } 1475 1476 /* 1477 * Actually link the two hooks together. 1478 */ 1479 hook1->hk_peer = hook2; 1480 hook2->hk_peer = hook1; 1481 1482 /* Each hook is referenced by the other */ 1483 NG_HOOK_REF(hook1); 1484 NG_HOOK_REF(hook2); 1485 1486 /* Give each node the opportunity to veto the pending connection */ 1487 if (hook1->hk_node->nd_type->connect) { 1488 error = (*hook1->hk_node->nd_type->connect) (hook1); 1489 } 1490 1491 if ((error == 0) && hook2->hk_node->nd_type->connect) { 1492 error = (*hook2->hk_node->nd_type->connect) (hook2); 1493 1494 } 1495 1496 /* 1497 * drop the references we were holding on the two hooks. 1498 */ 1499 if (error) { 1500 ng_destroy_hook(hook2); /* also zaps hook1 */ 1501 ng_rmnode(node2, NULL, NULL, 0); 1502 } else { 1503 /* As a last act, allow the hooks to be used */ 1504 hook1->hk_flags &= ~HK_INVALID; 1505 hook2->hk_flags &= ~HK_INVALID; 1506 } 1507 NG_HOOK_UNREF(hook1); 1508 NG_HOOK_UNREF(hook2); 1509 return (error); 1510 } 1511 1512 /************************************************************************ 1513 Utility routines to send self messages 1514 ************************************************************************/ 1515 1516 /* Shut this node down as soon as everyone is clear of it */ 1517 /* Should add arg "immediately" to jump the queue */ 1518 int 1519 ng_rmnode_self(node_p node) 1520 { 1521 int error; 1522 1523 if (node == &ng_deadnode) 1524 return (0); 1525 node->nd_flags |= NGF_INVALID; 1526 if (node->nd_flags & NGF_CLOSING) 1527 return (0); 1528 1529 error = ng_send_fn(node, NULL, &ng_rmnode, NULL, 0); 1530 return (error); 1531 } 1532 1533 static void 1534 ng_rmhook_part2(node_p node, hook_p hook, void *arg1, int arg2) 1535 { 1536 ng_destroy_hook(hook); 1537 return ; 1538 } 1539 1540 int 1541 ng_rmhook_self(hook_p hook) 1542 { 1543 int error; 1544 node_p node = NG_HOOK_NODE(hook); 1545 1546 if (node == &ng_deadnode) 1547 return (0); 1548 1549 error = ng_send_fn(node, hook, &ng_rmhook_part2, NULL, 0); 1550 return (error); 1551 } 1552 1553 /*********************************************************************** 1554 * Parse and verify a string of the form: <NODE:><PATH> 1555 * 1556 * Such a string can refer to a specific node or a specific hook 1557 * on a specific node, depending on how you look at it. In the 1558 * latter case, the PATH component must not end in a dot. 1559 * 1560 * Both <NODE:> and <PATH> are optional. The <PATH> is a string 1561 * of hook names separated by dots. This breaks out the original 1562 * string, setting *nodep to "NODE" (or NULL if none) and *pathp 1563 * to "PATH" (or NULL if degenerate). Also, *hookp will point to 1564 * the final hook component of <PATH>, if any, otherwise NULL. 1565 * 1566 * This returns -1 if the path is malformed. The char ** are optional. 1567 ***********************************************************************/ 1568 int 1569 ng_path_parse(char *addr, char **nodep, char **pathp, char **hookp) 1570 { 1571 char *node, *path, *hook; 1572 int k; 1573 1574 /* 1575 * Extract absolute NODE, if any 1576 */ 1577 for (path = addr; *path && *path != ':'; path++); 1578 if (*path) { 1579 node = addr; /* Here's the NODE */ 1580 *path++ = '\0'; /* Here's the PATH */ 1581 1582 /* Node name must not be empty */ 1583 if (!*node) 1584 return -1; 1585 1586 /* A name of "." is OK; otherwise '.' not allowed */ 1587 if (strcmp(node, ".") != 0) { 1588 for (k = 0; node[k]; k++) 1589 if (node[k] == '.') 1590 return -1; 1591 } 1592 } else { 1593 node = NULL; /* No absolute NODE */ 1594 path = addr; /* Here's the PATH */ 1595 } 1596 1597 /* Snoop for illegal characters in PATH */ 1598 for (k = 0; path[k]; k++) 1599 if (path[k] == ':') 1600 return -1; 1601 1602 /* Check for no repeated dots in PATH */ 1603 for (k = 0; path[k]; k++) 1604 if (path[k] == '.' && path[k + 1] == '.') 1605 return -1; 1606 1607 /* Remove extra (degenerate) dots from beginning or end of PATH */ 1608 if (path[0] == '.') 1609 path++; 1610 if (*path && path[strlen(path) - 1] == '.') 1611 path[strlen(path) - 1] = 0; 1612 1613 /* If PATH has a dot, then we're not talking about a hook */ 1614 if (*path) { 1615 for (hook = path, k = 0; path[k]; k++) 1616 if (path[k] == '.') { 1617 hook = NULL; 1618 break; 1619 } 1620 } else 1621 path = hook = NULL; 1622 1623 /* Done */ 1624 if (nodep) 1625 *nodep = node; 1626 if (pathp) 1627 *pathp = path; 1628 if (hookp) 1629 *hookp = hook; 1630 return (0); 1631 } 1632 1633 /* 1634 * Given a path, which may be absolute or relative, and a starting node, 1635 * return the destination node. 1636 */ 1637 int 1638 ng_path2noderef(node_p here, const char *address, 1639 node_p *destp, hook_p *lasthook) 1640 { 1641 char fullpath[NG_PATHSIZ]; 1642 char *nodename, *path; 1643 node_p node, oldnode; 1644 1645 /* Initialize */ 1646 if (destp == NULL) { 1647 TRAP_ERROR(); 1648 return EINVAL; 1649 } 1650 *destp = NULL; 1651 1652 /* Make a writable copy of address for ng_path_parse() */ 1653 strncpy(fullpath, address, sizeof(fullpath) - 1); 1654 fullpath[sizeof(fullpath) - 1] = '\0'; 1655 1656 /* Parse out node and sequence of hooks */ 1657 if (ng_path_parse(fullpath, &nodename, &path, NULL) < 0) { 1658 TRAP_ERROR(); 1659 return EINVAL; 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 if (path == NULL) { 1683 if (lasthook != NULL) 1684 *lasthook = NULL; 1685 *destp = node; 1686 return (0); 1687 } 1688 1689 /* 1690 * Now follow the sequence of hooks 1691 * 1692 * XXXGL: The path may demolish as we go the sequence, but if 1693 * we hold the topology mutex at critical places, then, I hope, 1694 * we would always have valid pointers in hand, although the 1695 * path behind us may no longer exist. 1696 */ 1697 for (;;) { 1698 hook_p hook; 1699 char *segment; 1700 1701 /* 1702 * Break out the next path segment. Replace the dot we just 1703 * found with a NUL; "path" points to the next segment (or the 1704 * NUL at the end). 1705 */ 1706 for (segment = path; *path != '\0'; path++) { 1707 if (*path == '.') { 1708 *path++ = '\0'; 1709 break; 1710 } 1711 } 1712 1713 /* We have a segment, so look for a hook by that name */ 1714 hook = ng_findhook(node, segment); 1715 1716 mtx_lock(&ng_topo_mtx); 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 mtx_unlock(&ng_topo_mtx); 1725 return (ENOENT); 1726 } 1727 1728 /* 1729 * Hop on over to the next node 1730 * XXX 1731 * Big race conditions here as hooks and nodes go away 1732 * *** Idea.. store an ng_ID_t in each hook and use that 1733 * instead of the direct hook in this crawl? 1734 */ 1735 oldnode = node; 1736 if ((node = NG_PEER_NODE(hook))) 1737 NG_NODE_REF(node); /* XXX RACE */ 1738 NG_NODE_UNREF(oldnode); /* XXX another race */ 1739 if (NG_NODE_NOT_VALID(node)) { 1740 NG_NODE_UNREF(node); /* XXX more races */ 1741 mtx_unlock(&ng_topo_mtx); 1742 TRAP_ERROR(); 1743 return (ENXIO); 1744 } 1745 1746 if (*path == '\0') { 1747 if (lasthook != NULL) { 1748 if (hook != NULL) { 1749 *lasthook = NG_HOOK_PEER(hook); 1750 NG_HOOK_REF(*lasthook); 1751 } else 1752 *lasthook = NULL; 1753 } 1754 mtx_unlock(&ng_topo_mtx); 1755 *destp = node; 1756 return (0); 1757 } 1758 mtx_unlock(&ng_topo_mtx); 1759 } 1760 } 1761 1762 /***************************************************************\ 1763 * Input queue handling. 1764 * All activities are submitted to the node via the input queue 1765 * which implements a multiple-reader/single-writer gate. 1766 * Items which cannot be handled immediately are queued. 1767 * 1768 * read-write queue locking inline functions * 1769 \***************************************************************/ 1770 1771 static __inline void ng_queue_rw(node_p node, item_p item, int rw); 1772 static __inline item_p ng_dequeue(node_p node, int *rw); 1773 static __inline item_p ng_acquire_read(node_p node, item_p item); 1774 static __inline item_p ng_acquire_write(node_p node, item_p item); 1775 static __inline void ng_leave_read(node_p node); 1776 static __inline void ng_leave_write(node_p node); 1777 1778 /* 1779 * Definition of the bits fields in the ng_queue flag word. 1780 * Defined here rather than in netgraph.h because no-one should fiddle 1781 * with them. 1782 * 1783 * The ordering here may be important! don't shuffle these. 1784 */ 1785 /*- 1786 Safety Barrier--------+ (adjustable to suit taste) (not used yet) 1787 | 1788 V 1789 +-------+-------+-------+-------+-------+-------+-------+-------+ 1790 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 1791 | |A|c|t|i|v|e| |R|e|a|d|e|r| |C|o|u|n|t| | | | | | | | | |P|A| 1792 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |O|W| 1793 +-------+-------+-------+-------+-------+-------+-------+-------+ 1794 \___________________________ ____________________________/ | | 1795 V | | 1796 [active reader count] | | 1797 | | 1798 Operation Pending -------------------------------+ | 1799 | 1800 Active Writer ---------------------------------------+ 1801 1802 Node queue has such semantics: 1803 - All flags modifications are atomic. 1804 - Reader count can be incremented only if there is no writer or pending flags. 1805 As soon as this can't be done with single operation, it is implemented with 1806 spin loop and atomic_cmpset(). 1807 - Writer flag can be set only if there is no any bits set. 1808 It is implemented with atomic_cmpset(). 1809 - Pending flag can be set any time, but to avoid collision on queue processing 1810 all queue fields are protected by the mutex. 1811 - Queue processing thread reads queue holding the mutex, but releases it while 1812 processing. When queue is empty pending flag is removed. 1813 */ 1814 1815 #define WRITER_ACTIVE 0x00000001 1816 #define OP_PENDING 0x00000002 1817 #define READER_INCREMENT 0x00000004 1818 #define READER_MASK 0xfffffffc /* Not valid if WRITER_ACTIVE is set */ 1819 #define SAFETY_BARRIER 0x00100000 /* 128K items queued should be enough */ 1820 1821 /* Defines of more elaborate states on the queue */ 1822 /* Mask of bits a new read cares about */ 1823 #define NGQ_RMASK (WRITER_ACTIVE|OP_PENDING) 1824 1825 /* Mask of bits a new write cares about */ 1826 #define NGQ_WMASK (NGQ_RMASK|READER_MASK) 1827 1828 /* Test to decide if there is something on the queue. */ 1829 #define QUEUE_ACTIVE(QP) ((QP)->q_flags & OP_PENDING) 1830 1831 /* How to decide what the next queued item is. */ 1832 #define HEAD_IS_READER(QP) NGI_QUEUED_READER(STAILQ_FIRST(&(QP)->queue)) 1833 #define HEAD_IS_WRITER(QP) NGI_QUEUED_WRITER(STAILQ_FIRST(&(QP)->queue)) /* notused */ 1834 1835 /* Read the status to decide if the next item on the queue can now run. */ 1836 #define QUEUED_READER_CAN_PROCEED(QP) \ 1837 (((QP)->q_flags & (NGQ_RMASK & ~OP_PENDING)) == 0) 1838 #define QUEUED_WRITER_CAN_PROCEED(QP) \ 1839 (((QP)->q_flags & (NGQ_WMASK & ~OP_PENDING)) == 0) 1840 1841 /* Is there a chance of getting ANY work off the queue? */ 1842 #define NEXT_QUEUED_ITEM_CAN_PROCEED(QP) \ 1843 ((HEAD_IS_READER(QP)) ? QUEUED_READER_CAN_PROCEED(QP) : \ 1844 QUEUED_WRITER_CAN_PROCEED(QP)) 1845 1846 #define NGQRW_R 0 1847 #define NGQRW_W 1 1848 1849 #define NGQ2_WORKQ 0x00000001 1850 1851 /* 1852 * Taking into account the current state of the queue and node, possibly take 1853 * the next entry off the queue and return it. Return NULL if there was 1854 * nothing we could return, either because there really was nothing there, or 1855 * because the node was in a state where it cannot yet process the next item 1856 * on the queue. 1857 */ 1858 static __inline item_p 1859 ng_dequeue(node_p node, int *rw) 1860 { 1861 item_p item; 1862 struct ng_queue *ngq = &node->nd_input_queue; 1863 1864 /* This MUST be called with the mutex held. */ 1865 mtx_assert(&ngq->q_mtx, MA_OWNED); 1866 1867 /* If there is nothing queued, then just return. */ 1868 if (!QUEUE_ACTIVE(ngq)) { 1869 CTR4(KTR_NET, "%20s: node [%x] (%p) queue empty; " 1870 "queue flags 0x%lx", __func__, 1871 node->nd_ID, node, ngq->q_flags); 1872 return (NULL); 1873 } 1874 1875 /* 1876 * From here, we can assume there is a head item. 1877 * We need to find out what it is and if it can be dequeued, given 1878 * the current state of the node. 1879 */ 1880 if (HEAD_IS_READER(ngq)) { 1881 while (1) { 1882 long t = ngq->q_flags; 1883 if (t & WRITER_ACTIVE) { 1884 /* There is writer, reader can't proceed. */ 1885 CTR4(KTR_NET, "%20s: node [%x] (%p) queued reader " 1886 "can't proceed; queue flags 0x%lx", __func__, 1887 node->nd_ID, node, t); 1888 return (NULL); 1889 } 1890 if (atomic_cmpset_acq_int(&ngq->q_flags, t, 1891 t + READER_INCREMENT)) 1892 break; 1893 cpu_spinwait(); 1894 } 1895 /* We have got reader lock for the node. */ 1896 *rw = NGQRW_R; 1897 } else if (atomic_cmpset_acq_int(&ngq->q_flags, OP_PENDING, 1898 OP_PENDING + WRITER_ACTIVE)) { 1899 /* We have got writer lock for the node. */ 1900 *rw = NGQRW_W; 1901 } else { 1902 /* There is somebody other, writer can't proceed. */ 1903 CTR4(KTR_NET, "%20s: node [%x] (%p) queued writer " 1904 "can't proceed; queue flags 0x%lx", __func__, 1905 node->nd_ID, node, ngq->q_flags); 1906 return (NULL); 1907 } 1908 1909 /* 1910 * Now we dequeue the request (whatever it may be) and correct the 1911 * pending flags and the next and last pointers. 1912 */ 1913 item = STAILQ_FIRST(&ngq->queue); 1914 STAILQ_REMOVE_HEAD(&ngq->queue, el_next); 1915 if (STAILQ_EMPTY(&ngq->queue)) 1916 atomic_clear_int(&ngq->q_flags, OP_PENDING); 1917 CTR6(KTR_NET, "%20s: node [%x] (%p) returning item %p as %s; " 1918 "queue flags 0x%lx", __func__, 1919 node->nd_ID, node, item, *rw ? "WRITER" : "READER" , 1920 ngq->q_flags); 1921 return (item); 1922 } 1923 1924 /* 1925 * Queue a packet to be picked up later by someone else. 1926 * If the queue could be run now, add node to the queue handler's worklist. 1927 */ 1928 static __inline void 1929 ng_queue_rw(node_p node, item_p item, int rw) 1930 { 1931 struct ng_queue *ngq = &node->nd_input_queue; 1932 if (rw == NGQRW_W) 1933 NGI_SET_WRITER(item); 1934 else 1935 NGI_SET_READER(item); 1936 1937 NG_QUEUE_LOCK(ngq); 1938 /* Set OP_PENDING flag and enqueue the item. */ 1939 atomic_set_int(&ngq->q_flags, OP_PENDING); 1940 STAILQ_INSERT_TAIL(&ngq->queue, item, el_next); 1941 1942 CTR5(KTR_NET, "%20s: node [%x] (%p) queued item %p as %s", __func__, 1943 node->nd_ID, node, item, rw ? "WRITER" : "READER" ); 1944 1945 /* 1946 * We can take the worklist lock with the node locked 1947 * BUT NOT THE REVERSE! 1948 */ 1949 if (NEXT_QUEUED_ITEM_CAN_PROCEED(ngq)) 1950 ng_worklist_add(node); 1951 NG_QUEUE_UNLOCK(ngq); 1952 } 1953 1954 /* Acquire reader lock on node. If node is busy, queue the packet. */ 1955 static __inline item_p 1956 ng_acquire_read(node_p node, item_p item) 1957 { 1958 KASSERT(node != &ng_deadnode, 1959 ("%s: working on deadnode", __func__)); 1960 1961 /* Reader needs node without writer and pending items. */ 1962 while (1) { 1963 long t = node->nd_input_queue.q_flags; 1964 if (t & NGQ_RMASK) 1965 break; /* Node is not ready for reader. */ 1966 if (atomic_cmpset_acq_int(&node->nd_input_queue.q_flags, 1967 t, t + READER_INCREMENT)) { 1968 /* Successfully grabbed node */ 1969 CTR4(KTR_NET, "%20s: node [%x] (%p) acquired item %p", 1970 __func__, node->nd_ID, node, item); 1971 return (item); 1972 } 1973 cpu_spinwait(); 1974 }; 1975 1976 /* Queue the request for later. */ 1977 ng_queue_rw(node, item, NGQRW_R); 1978 1979 return (NULL); 1980 } 1981 1982 /* Acquire writer lock on node. If node is busy, queue the packet. */ 1983 static __inline item_p 1984 ng_acquire_write(node_p node, item_p item) 1985 { 1986 KASSERT(node != &ng_deadnode, 1987 ("%s: working on deadnode", __func__)); 1988 1989 /* Writer needs completely idle node. */ 1990 if (atomic_cmpset_acq_int(&node->nd_input_queue.q_flags, 1991 0, WRITER_ACTIVE)) { 1992 /* Successfully grabbed node */ 1993 CTR4(KTR_NET, "%20s: node [%x] (%p) acquired item %p", 1994 __func__, node->nd_ID, node, item); 1995 return (item); 1996 } 1997 1998 /* Queue the request for later. */ 1999 ng_queue_rw(node, item, NGQRW_W); 2000 2001 return (NULL); 2002 } 2003 2004 #if 0 2005 static __inline item_p 2006 ng_upgrade_write(node_p node, item_p item) 2007 { 2008 struct ng_queue *ngq = &node->nd_input_queue; 2009 KASSERT(node != &ng_deadnode, 2010 ("%s: working on deadnode", __func__)); 2011 2012 NGI_SET_WRITER(item); 2013 2014 NG_QUEUE_LOCK(ngq); 2015 2016 /* 2017 * There will never be no readers as we are there ourselves. 2018 * Set the WRITER_ACTIVE flags ASAP to block out fast track readers. 2019 * The caller we are running from will call ng_leave_read() 2020 * soon, so we must account for that. We must leave again with the 2021 * READER lock. If we find other readers, then 2022 * queue the request for later. However "later" may be rignt now 2023 * if there are no readers. We don't really care if there are queued 2024 * items as we will bypass them anyhow. 2025 */ 2026 atomic_add_int(&ngq->q_flags, WRITER_ACTIVE - READER_INCREMENT); 2027 if ((ngq->q_flags & (NGQ_WMASK & ~OP_PENDING)) == WRITER_ACTIVE) { 2028 NG_QUEUE_UNLOCK(ngq); 2029 2030 /* It's just us, act on the item. */ 2031 /* will NOT drop writer lock when done */ 2032 ng_apply_item(node, item, 0); 2033 2034 /* 2035 * Having acted on the item, atomically 2036 * down grade back to READER and finish up 2037 */ 2038 atomic_add_int(&ngq->q_flags, 2039 READER_INCREMENT - WRITER_ACTIVE); 2040 2041 /* Our caller will call ng_leave_read() */ 2042 return; 2043 } 2044 /* 2045 * It's not just us active, so queue us AT THE HEAD. 2046 * "Why?" I hear you ask. 2047 * Put us at the head of the queue as we've already been 2048 * through it once. If there is nothing else waiting, 2049 * set the correct flags. 2050 */ 2051 if (STAILQ_EMPTY(&ngq->queue)) { 2052 /* We've gone from, 0 to 1 item in the queue */ 2053 atomic_set_int(&ngq->q_flags, OP_PENDING); 2054 2055 CTR3(KTR_NET, "%20s: node [%x] (%p) set OP_PENDING", __func__, 2056 node->nd_ID, node); 2057 }; 2058 STAILQ_INSERT_HEAD(&ngq->queue, item, el_next); 2059 CTR4(KTR_NET, "%20s: node [%x] (%p) requeued item %p as WRITER", 2060 __func__, node->nd_ID, node, item ); 2061 2062 /* Reverse what we did above. That downgrades us back to reader */ 2063 atomic_add_int(&ngq->q_flags, READER_INCREMENT - WRITER_ACTIVE); 2064 if (QUEUE_ACTIVE(ngq) && NEXT_QUEUED_ITEM_CAN_PROCEED(ngq)) 2065 ng_worklist_add(node); 2066 NG_QUEUE_UNLOCK(ngq); 2067 2068 return; 2069 } 2070 #endif 2071 2072 /* Release reader lock. */ 2073 static __inline void 2074 ng_leave_read(node_p node) 2075 { 2076 atomic_subtract_rel_int(&node->nd_input_queue.q_flags, READER_INCREMENT); 2077 } 2078 2079 /* Release writer lock. */ 2080 static __inline void 2081 ng_leave_write(node_p node) 2082 { 2083 atomic_clear_rel_int(&node->nd_input_queue.q_flags, WRITER_ACTIVE); 2084 } 2085 2086 /* Purge node queue. Called on node shutdown. */ 2087 static void 2088 ng_flush_input_queue(node_p node) 2089 { 2090 struct ng_queue *ngq = &node->nd_input_queue; 2091 item_p item; 2092 2093 NG_QUEUE_LOCK(ngq); 2094 while ((item = STAILQ_FIRST(&ngq->queue)) != NULL) { 2095 STAILQ_REMOVE_HEAD(&ngq->queue, el_next); 2096 if (STAILQ_EMPTY(&ngq->queue)) 2097 atomic_clear_int(&ngq->q_flags, OP_PENDING); 2098 NG_QUEUE_UNLOCK(ngq); 2099 2100 /* If the item is supplying a callback, call it with an error */ 2101 if (item->apply != NULL) { 2102 if (item->depth == 1) 2103 item->apply->error = ENOENT; 2104 if (refcount_release(&item->apply->refs)) { 2105 (*item->apply->apply)(item->apply->context, 2106 item->apply->error); 2107 } 2108 } 2109 NG_FREE_ITEM(item); 2110 NG_QUEUE_LOCK(ngq); 2111 } 2112 NG_QUEUE_UNLOCK(ngq); 2113 } 2114 2115 /*********************************************************************** 2116 * Externally visible method for sending or queueing messages or data. 2117 ***********************************************************************/ 2118 2119 /* 2120 * The module code should have filled out the item correctly by this stage: 2121 * Common: 2122 * reference to destination node. 2123 * Reference to destination rcv hook if relevant. 2124 * apply pointer must be or NULL or reference valid struct ng_apply_info. 2125 * Data: 2126 * pointer to mbuf 2127 * Control_Message: 2128 * pointer to msg. 2129 * ID of original sender node. (return address) 2130 * Function: 2131 * Function pointer 2132 * void * argument 2133 * integer argument 2134 * 2135 * The nodes have several routines and macros to help with this task: 2136 */ 2137 2138 int 2139 ng_snd_item(item_p item, int flags) 2140 { 2141 hook_p hook; 2142 node_p node; 2143 int queue, rw; 2144 struct ng_queue *ngq; 2145 int error = 0; 2146 2147 /* We are sending item, so it must be present! */ 2148 KASSERT(item != NULL, ("ng_snd_item: item is NULL")); 2149 2150 #ifdef NETGRAPH_DEBUG 2151 _ngi_check(item, __FILE__, __LINE__); 2152 #endif 2153 2154 /* Item was sent once more, postpone apply() call. */ 2155 if (item->apply) 2156 refcount_acquire(&item->apply->refs); 2157 2158 node = NGI_NODE(item); 2159 /* Node is never optional. */ 2160 KASSERT(node != NULL, ("ng_snd_item: node is NULL")); 2161 2162 hook = NGI_HOOK(item); 2163 /* Valid hook and mbuf are mandatory for data. */ 2164 if ((item->el_flags & NGQF_TYPE) == NGQF_DATA) { 2165 KASSERT(hook != NULL, ("ng_snd_item: hook for data is NULL")); 2166 if (NGI_M(item) == NULL) 2167 ERROUT(EINVAL); 2168 CHECK_DATA_MBUF(NGI_M(item)); 2169 } 2170 2171 /* 2172 * If the item or the node specifies single threading, force 2173 * writer semantics. Similarly, the node may say one hook always 2174 * produces writers. These are overrides. 2175 */ 2176 if (((item->el_flags & NGQF_RW) == NGQF_WRITER) || 2177 (node->nd_flags & NGF_FORCE_WRITER) || 2178 (hook && (hook->hk_flags & HK_FORCE_WRITER))) { 2179 rw = NGQRW_W; 2180 } else { 2181 rw = NGQRW_R; 2182 } 2183 2184 /* 2185 * If sender or receiver requests queued delivery, or call graph 2186 * loops back from outbound to inbound path, or stack usage 2187 * level is dangerous - enqueue message. 2188 */ 2189 if ((flags & NG_QUEUE) || (hook && (hook->hk_flags & HK_QUEUE))) { 2190 queue = 1; 2191 } else if (hook && (hook->hk_flags & HK_TO_INBOUND) && 2192 curthread->td_ng_outbound) { 2193 queue = 1; 2194 } else { 2195 queue = 0; 2196 #ifdef GET_STACK_USAGE 2197 /* 2198 * Most of netgraph nodes have small stack consumption and 2199 * for them 25% of free stack space is more than enough. 2200 * Nodes/hooks with higher stack usage should be marked as 2201 * HI_STACK. For them 50% of stack will be guaranteed then. 2202 * XXX: Values 25% and 50% are completely empirical. 2203 */ 2204 size_t st, su, sl; 2205 GET_STACK_USAGE(st, su); 2206 sl = st - su; 2207 if ((sl * 4 < st) || 2208 ((sl * 2 < st) && ((node->nd_flags & NGF_HI_STACK) || 2209 (hook && (hook->hk_flags & HK_HI_STACK))))) { 2210 queue = 1; 2211 } 2212 #endif 2213 } 2214 2215 if (queue) { 2216 item->depth = 1; 2217 /* Put it on the queue for that node*/ 2218 ng_queue_rw(node, item, rw); 2219 return ((flags & NG_PROGRESS) ? EINPROGRESS : 0); 2220 } 2221 2222 /* 2223 * We already decided how we will be queueud or treated. 2224 * Try get the appropriate operating permission. 2225 */ 2226 if (rw == NGQRW_R) 2227 item = ng_acquire_read(node, item); 2228 else 2229 item = ng_acquire_write(node, item); 2230 2231 /* Item was queued while trying to get permission. */ 2232 if (item == NULL) 2233 return ((flags & NG_PROGRESS) ? EINPROGRESS : 0); 2234 2235 NGI_GET_NODE(item, node); /* zaps stored node */ 2236 2237 item->depth++; 2238 error = ng_apply_item(node, item, rw); /* drops r/w lock when done */ 2239 2240 /* If something is waiting on queue and ready, schedule it. */ 2241 ngq = &node->nd_input_queue; 2242 if (QUEUE_ACTIVE(ngq)) { 2243 NG_QUEUE_LOCK(ngq); 2244 if (QUEUE_ACTIVE(ngq) && NEXT_QUEUED_ITEM_CAN_PROCEED(ngq)) 2245 ng_worklist_add(node); 2246 NG_QUEUE_UNLOCK(ngq); 2247 } 2248 2249 /* 2250 * Node may go away as soon as we remove the reference. 2251 * Whatever we do, DO NOT access the node again! 2252 */ 2253 NG_NODE_UNREF(node); 2254 2255 return (error); 2256 2257 done: 2258 /* If was not sent, apply callback here. */ 2259 if (item->apply != NULL) { 2260 if (item->depth == 0 && error != 0) 2261 item->apply->error = error; 2262 if (refcount_release(&item->apply->refs)) { 2263 (*item->apply->apply)(item->apply->context, 2264 item->apply->error); 2265 } 2266 } 2267 2268 NG_FREE_ITEM(item); 2269 return (error); 2270 } 2271 2272 /* 2273 * We have an item that was possibly queued somewhere. 2274 * It should contain all the information needed 2275 * to run it on the appropriate node/hook. 2276 * If there is apply pointer and we own the last reference, call apply(). 2277 */ 2278 static int 2279 ng_apply_item(node_p node, item_p item, int rw) 2280 { 2281 hook_p hook; 2282 ng_rcvdata_t *rcvdata; 2283 ng_rcvmsg_t *rcvmsg; 2284 struct ng_apply_info *apply; 2285 int error = 0, depth; 2286 2287 /* Node and item are never optional. */ 2288 KASSERT(node != NULL, ("ng_apply_item: node is NULL")); 2289 KASSERT(item != NULL, ("ng_apply_item: item is NULL")); 2290 2291 NGI_GET_HOOK(item, hook); /* clears stored hook */ 2292 #ifdef NETGRAPH_DEBUG 2293 _ngi_check(item, __FILE__, __LINE__); 2294 #endif 2295 2296 apply = item->apply; 2297 depth = item->depth; 2298 2299 switch (item->el_flags & NGQF_TYPE) { 2300 case NGQF_DATA: 2301 /* 2302 * Check things are still ok as when we were queued. 2303 */ 2304 KASSERT(hook != NULL, ("ng_apply_item: hook for data is NULL")); 2305 if (NG_HOOK_NOT_VALID(hook) || 2306 NG_NODE_NOT_VALID(node)) { 2307 error = EIO; 2308 NG_FREE_ITEM(item); 2309 break; 2310 } 2311 /* 2312 * If no receive method, just silently drop it. 2313 * Give preference to the hook over-ride method 2314 */ 2315 if ((!(rcvdata = hook->hk_rcvdata)) 2316 && (!(rcvdata = NG_HOOK_NODE(hook)->nd_type->rcvdata))) { 2317 error = 0; 2318 NG_FREE_ITEM(item); 2319 break; 2320 } 2321 error = (*rcvdata)(hook, item); 2322 break; 2323 case NGQF_MESG: 2324 if (hook && NG_HOOK_NOT_VALID(hook)) { 2325 /* 2326 * The hook has been zapped then we can't use it. 2327 * Immediately drop its reference. 2328 * The message may not need it. 2329 */ 2330 NG_HOOK_UNREF(hook); 2331 hook = NULL; 2332 } 2333 /* 2334 * Similarly, if the node is a zombie there is 2335 * nothing we can do with it, drop everything. 2336 */ 2337 if (NG_NODE_NOT_VALID(node)) { 2338 TRAP_ERROR(); 2339 error = EINVAL; 2340 NG_FREE_ITEM(item); 2341 break; 2342 } 2343 /* 2344 * Call the appropriate message handler for the object. 2345 * It is up to the message handler to free the message. 2346 * If it's a generic message, handle it generically, 2347 * otherwise call the type's message handler (if it exists). 2348 * XXX (race). Remember that a queued message may 2349 * reference a node or hook that has just been 2350 * invalidated. It will exist as the queue code 2351 * is holding a reference, but.. 2352 */ 2353 if ((NGI_MSG(item)->header.typecookie == NGM_GENERIC_COOKIE) && 2354 ((NGI_MSG(item)->header.flags & NGF_RESP) == 0)) { 2355 error = ng_generic_msg(node, item, hook); 2356 break; 2357 } 2358 if (((!hook) || (!(rcvmsg = hook->hk_rcvmsg))) && 2359 (!(rcvmsg = node->nd_type->rcvmsg))) { 2360 TRAP_ERROR(); 2361 error = 0; 2362 NG_FREE_ITEM(item); 2363 break; 2364 } 2365 error = (*rcvmsg)(node, item, hook); 2366 break; 2367 case NGQF_FN: 2368 case NGQF_FN2: 2369 /* 2370 * In the case of the shutdown message we allow it to hit 2371 * even if the node is invalid. 2372 */ 2373 if (NG_NODE_NOT_VALID(node) && 2374 NGI_FN(item) != &ng_rmnode) { 2375 TRAP_ERROR(); 2376 error = EINVAL; 2377 NG_FREE_ITEM(item); 2378 break; 2379 } 2380 /* Same is about some internal functions and invalid hook. */ 2381 if (hook && NG_HOOK_NOT_VALID(hook) && 2382 NGI_FN2(item) != &ng_con_part2 && 2383 NGI_FN2(item) != &ng_con_part3 && 2384 NGI_FN(item) != &ng_rmhook_part2) { 2385 TRAP_ERROR(); 2386 error = EINVAL; 2387 NG_FREE_ITEM(item); 2388 break; 2389 } 2390 2391 if ((item->el_flags & NGQF_TYPE) == NGQF_FN) { 2392 (*NGI_FN(item))(node, hook, NGI_ARG1(item), 2393 NGI_ARG2(item)); 2394 NG_FREE_ITEM(item); 2395 } else /* it is NGQF_FN2 */ 2396 error = (*NGI_FN2(item))(node, item, hook); 2397 break; 2398 } 2399 /* 2400 * We held references on some of the resources 2401 * that we took from the item. Now that we have 2402 * finished doing everything, drop those references. 2403 */ 2404 if (hook) 2405 NG_HOOK_UNREF(hook); 2406 2407 if (rw == NGQRW_R) 2408 ng_leave_read(node); 2409 else 2410 ng_leave_write(node); 2411 2412 /* Apply callback. */ 2413 if (apply != NULL) { 2414 if (depth == 1 && error != 0) 2415 apply->error = error; 2416 if (refcount_release(&apply->refs)) 2417 (*apply->apply)(apply->context, apply->error); 2418 } 2419 2420 return (error); 2421 } 2422 2423 /*********************************************************************** 2424 * Implement the 'generic' control messages 2425 ***********************************************************************/ 2426 static int 2427 ng_generic_msg(node_p here, item_p item, hook_p lasthook) 2428 { 2429 int error = 0; 2430 struct ng_mesg *msg; 2431 struct ng_mesg *resp = NULL; 2432 2433 NGI_GET_MSG(item, msg); 2434 if (msg->header.typecookie != NGM_GENERIC_COOKIE) { 2435 TRAP_ERROR(); 2436 error = EINVAL; 2437 goto out; 2438 } 2439 switch (msg->header.cmd) { 2440 case NGM_SHUTDOWN: 2441 ng_rmnode(here, NULL, NULL, 0); 2442 break; 2443 case NGM_MKPEER: 2444 { 2445 struct ngm_mkpeer *const mkp = (struct ngm_mkpeer *) msg->data; 2446 2447 if (msg->header.arglen != sizeof(*mkp)) { 2448 TRAP_ERROR(); 2449 error = EINVAL; 2450 break; 2451 } 2452 mkp->type[sizeof(mkp->type) - 1] = '\0'; 2453 mkp->ourhook[sizeof(mkp->ourhook) - 1] = '\0'; 2454 mkp->peerhook[sizeof(mkp->peerhook) - 1] = '\0'; 2455 error = ng_mkpeer(here, mkp->ourhook, mkp->peerhook, mkp->type); 2456 break; 2457 } 2458 case NGM_CONNECT: 2459 { 2460 struct ngm_connect *const con = 2461 (struct ngm_connect *) msg->data; 2462 node_p node2; 2463 2464 if (msg->header.arglen != sizeof(*con)) { 2465 TRAP_ERROR(); 2466 error = EINVAL; 2467 break; 2468 } 2469 con->path[sizeof(con->path) - 1] = '\0'; 2470 con->ourhook[sizeof(con->ourhook) - 1] = '\0'; 2471 con->peerhook[sizeof(con->peerhook) - 1] = '\0'; 2472 /* Don't forget we get a reference.. */ 2473 error = ng_path2noderef(here, con->path, &node2, NULL); 2474 if (error) 2475 break; 2476 error = ng_con_nodes(item, here, con->ourhook, 2477 node2, con->peerhook); 2478 NG_NODE_UNREF(node2); 2479 break; 2480 } 2481 case NGM_NAME: 2482 { 2483 struct ngm_name *const nam = (struct ngm_name *) msg->data; 2484 2485 if (msg->header.arglen != sizeof(*nam)) { 2486 TRAP_ERROR(); 2487 error = EINVAL; 2488 break; 2489 } 2490 nam->name[sizeof(nam->name) - 1] = '\0'; 2491 error = ng_name_node(here, nam->name); 2492 break; 2493 } 2494 case NGM_RMHOOK: 2495 { 2496 struct ngm_rmhook *const rmh = (struct ngm_rmhook *) msg->data; 2497 hook_p hook; 2498 2499 if (msg->header.arglen != sizeof(*rmh)) { 2500 TRAP_ERROR(); 2501 error = EINVAL; 2502 break; 2503 } 2504 rmh->ourhook[sizeof(rmh->ourhook) - 1] = '\0'; 2505 if ((hook = ng_findhook(here, rmh->ourhook)) != NULL) 2506 ng_destroy_hook(hook); 2507 break; 2508 } 2509 case NGM_NODEINFO: 2510 { 2511 struct nodeinfo *ni; 2512 2513 NG_MKRESPONSE(resp, msg, sizeof(*ni), M_NOWAIT); 2514 if (resp == NULL) { 2515 error = ENOMEM; 2516 break; 2517 } 2518 2519 /* Fill in node info */ 2520 ni = (struct nodeinfo *) resp->data; 2521 if (NG_NODE_HAS_NAME(here)) 2522 strcpy(ni->name, NG_NODE_NAME(here)); 2523 strcpy(ni->type, here->nd_type->name); 2524 ni->id = ng_node2ID(here); 2525 ni->hooks = here->nd_numhooks; 2526 break; 2527 } 2528 case NGM_LISTHOOKS: 2529 { 2530 const int nhooks = here->nd_numhooks; 2531 struct hooklist *hl; 2532 struct nodeinfo *ni; 2533 hook_p hook; 2534 2535 /* Get response struct */ 2536 NG_MKRESPONSE(resp, msg, sizeof(*hl) 2537 + (nhooks * sizeof(struct linkinfo)), M_NOWAIT); 2538 if (resp == NULL) { 2539 error = ENOMEM; 2540 break; 2541 } 2542 hl = (struct hooklist *) resp->data; 2543 ni = &hl->nodeinfo; 2544 2545 /* Fill in node info */ 2546 if (NG_NODE_HAS_NAME(here)) 2547 strcpy(ni->name, NG_NODE_NAME(here)); 2548 strcpy(ni->type, here->nd_type->name); 2549 ni->id = ng_node2ID(here); 2550 2551 /* Cycle through the linked list of hooks */ 2552 ni->hooks = 0; 2553 LIST_FOREACH(hook, &here->nd_hooks, hk_hooks) { 2554 struct linkinfo *const link = &hl->link[ni->hooks]; 2555 2556 if (ni->hooks >= nhooks) { 2557 log(LOG_ERR, "%s: number of %s changed\n", 2558 __func__, "hooks"); 2559 break; 2560 } 2561 if (NG_HOOK_NOT_VALID(hook)) 2562 continue; 2563 strcpy(link->ourhook, NG_HOOK_NAME(hook)); 2564 strcpy(link->peerhook, NG_PEER_HOOK_NAME(hook)); 2565 if (NG_PEER_NODE_NAME(hook)[0] != '\0') 2566 strcpy(link->nodeinfo.name, 2567 NG_PEER_NODE_NAME(hook)); 2568 strcpy(link->nodeinfo.type, 2569 NG_PEER_NODE(hook)->nd_type->name); 2570 link->nodeinfo.id = ng_node2ID(NG_PEER_NODE(hook)); 2571 link->nodeinfo.hooks = NG_PEER_NODE(hook)->nd_numhooks; 2572 ni->hooks++; 2573 } 2574 break; 2575 } 2576 2577 case NGM_LISTNAMES: 2578 case NGM_LISTNODES: 2579 { 2580 const int unnamed = (msg->header.cmd == NGM_LISTNODES); 2581 struct namelist *nl; 2582 node_p node; 2583 int num = 0, i; 2584 2585 mtx_lock(&ng_namehash_mtx); 2586 /* Count number of nodes */ 2587 for (i = 0; i < NG_NAME_HASH_SIZE; i++) { 2588 LIST_FOREACH(node, &V_ng_name_hash[i], nd_nodes) { 2589 if (NG_NODE_IS_VALID(node) && 2590 (unnamed || NG_NODE_HAS_NAME(node))) { 2591 num++; 2592 } 2593 } 2594 } 2595 mtx_unlock(&ng_namehash_mtx); 2596 2597 /* Get response struct */ 2598 NG_MKRESPONSE(resp, msg, sizeof(*nl) 2599 + (num * sizeof(struct nodeinfo)), M_NOWAIT); 2600 if (resp == NULL) { 2601 error = ENOMEM; 2602 break; 2603 } 2604 nl = (struct namelist *) resp->data; 2605 2606 /* Cycle through the linked list of nodes */ 2607 nl->numnames = 0; 2608 mtx_lock(&ng_namehash_mtx); 2609 for (i = 0; i < NG_NAME_HASH_SIZE; i++) { 2610 LIST_FOREACH(node, &V_ng_name_hash[i], nd_nodes) { 2611 struct nodeinfo *const np = 2612 &nl->nodeinfo[nl->numnames]; 2613 2614 if (NG_NODE_NOT_VALID(node)) 2615 continue; 2616 if (!unnamed && (! NG_NODE_HAS_NAME(node))) 2617 continue; 2618 if (nl->numnames >= num) { 2619 log(LOG_ERR, "%s: number of nodes changed\n", 2620 __func__); 2621 break; 2622 } 2623 if (NG_NODE_HAS_NAME(node)) 2624 strcpy(np->name, NG_NODE_NAME(node)); 2625 strcpy(np->type, node->nd_type->name); 2626 np->id = ng_node2ID(node); 2627 np->hooks = node->nd_numhooks; 2628 nl->numnames++; 2629 } 2630 } 2631 mtx_unlock(&ng_namehash_mtx); 2632 break; 2633 } 2634 2635 case NGM_LISTTYPES: 2636 { 2637 struct typelist *tl; 2638 struct ng_type *type; 2639 int num = 0; 2640 2641 mtx_lock(&ng_typelist_mtx); 2642 /* Count number of types */ 2643 LIST_FOREACH(type, &ng_typelist, types) { 2644 num++; 2645 } 2646 mtx_unlock(&ng_typelist_mtx); 2647 2648 /* Get response struct */ 2649 NG_MKRESPONSE(resp, msg, sizeof(*tl) 2650 + (num * sizeof(struct typeinfo)), M_NOWAIT); 2651 if (resp == NULL) { 2652 error = ENOMEM; 2653 break; 2654 } 2655 tl = (struct typelist *) resp->data; 2656 2657 /* Cycle through the linked list of types */ 2658 tl->numtypes = 0; 2659 mtx_lock(&ng_typelist_mtx); 2660 LIST_FOREACH(type, &ng_typelist, types) { 2661 struct typeinfo *const tp = &tl->typeinfo[tl->numtypes]; 2662 2663 if (tl->numtypes >= num) { 2664 log(LOG_ERR, "%s: number of %s changed\n", 2665 __func__, "types"); 2666 break; 2667 } 2668 strcpy(tp->type_name, type->name); 2669 tp->numnodes = type->refs - 1; /* don't count list */ 2670 tl->numtypes++; 2671 } 2672 mtx_unlock(&ng_typelist_mtx); 2673 break; 2674 } 2675 2676 case NGM_BINARY2ASCII: 2677 { 2678 int bufSize = 20 * 1024; /* XXX hard coded constant */ 2679 const struct ng_parse_type *argstype; 2680 const struct ng_cmdlist *c; 2681 struct ng_mesg *binary, *ascii; 2682 2683 /* Data area must contain a valid netgraph message */ 2684 binary = (struct ng_mesg *)msg->data; 2685 if (msg->header.arglen < sizeof(struct ng_mesg) || 2686 (msg->header.arglen - sizeof(struct ng_mesg) < 2687 binary->header.arglen)) { 2688 TRAP_ERROR(); 2689 error = EINVAL; 2690 break; 2691 } 2692 2693 /* Get a response message with lots of room */ 2694 NG_MKRESPONSE(resp, msg, sizeof(*ascii) + bufSize, M_NOWAIT); 2695 if (resp == NULL) { 2696 error = ENOMEM; 2697 break; 2698 } 2699 ascii = (struct ng_mesg *)resp->data; 2700 2701 /* Copy binary message header to response message payload */ 2702 bcopy(binary, ascii, sizeof(*binary)); 2703 2704 /* Find command by matching typecookie and command number */ 2705 for (c = here->nd_type->cmdlist; 2706 c != NULL && c->name != NULL; c++) { 2707 if (binary->header.typecookie == c->cookie 2708 && binary->header.cmd == c->cmd) 2709 break; 2710 } 2711 if (c == NULL || c->name == NULL) { 2712 for (c = ng_generic_cmds; c->name != NULL; c++) { 2713 if (binary->header.typecookie == c->cookie 2714 && binary->header.cmd == c->cmd) 2715 break; 2716 } 2717 if (c->name == NULL) { 2718 NG_FREE_MSG(resp); 2719 error = ENOSYS; 2720 break; 2721 } 2722 } 2723 2724 /* Convert command name to ASCII */ 2725 snprintf(ascii->header.cmdstr, sizeof(ascii->header.cmdstr), 2726 "%s", c->name); 2727 2728 /* Convert command arguments to ASCII */ 2729 argstype = (binary->header.flags & NGF_RESP) ? 2730 c->respType : c->mesgType; 2731 if (argstype == NULL) { 2732 *ascii->data = '\0'; 2733 } else { 2734 if ((error = ng_unparse(argstype, 2735 (u_char *)binary->data, 2736 ascii->data, bufSize)) != 0) { 2737 NG_FREE_MSG(resp); 2738 break; 2739 } 2740 } 2741 2742 /* Return the result as struct ng_mesg plus ASCII string */ 2743 bufSize = strlen(ascii->data) + 1; 2744 ascii->header.arglen = bufSize; 2745 resp->header.arglen = sizeof(*ascii) + bufSize; 2746 break; 2747 } 2748 2749 case NGM_ASCII2BINARY: 2750 { 2751 int bufSize = 20 * 1024; /* XXX hard coded constant */ 2752 const struct ng_cmdlist *c; 2753 const struct ng_parse_type *argstype; 2754 struct ng_mesg *ascii, *binary; 2755 int off = 0; 2756 2757 /* Data area must contain at least a struct ng_mesg + '\0' */ 2758 ascii = (struct ng_mesg *)msg->data; 2759 if ((msg->header.arglen < sizeof(*ascii) + 1) || 2760 (ascii->header.arglen < 1) || 2761 (msg->header.arglen < sizeof(*ascii) + 2762 ascii->header.arglen)) { 2763 TRAP_ERROR(); 2764 error = EINVAL; 2765 break; 2766 } 2767 ascii->data[ascii->header.arglen - 1] = '\0'; 2768 2769 /* Get a response message with lots of room */ 2770 NG_MKRESPONSE(resp, msg, sizeof(*binary) + bufSize, M_NOWAIT); 2771 if (resp == NULL) { 2772 error = ENOMEM; 2773 break; 2774 } 2775 binary = (struct ng_mesg *)resp->data; 2776 2777 /* Copy ASCII message header to response message payload */ 2778 bcopy(ascii, binary, sizeof(*ascii)); 2779 2780 /* Find command by matching ASCII command string */ 2781 for (c = here->nd_type->cmdlist; 2782 c != NULL && c->name != NULL; c++) { 2783 if (strcmp(ascii->header.cmdstr, c->name) == 0) 2784 break; 2785 } 2786 if (c == NULL || c->name == NULL) { 2787 for (c = ng_generic_cmds; c->name != NULL; c++) { 2788 if (strcmp(ascii->header.cmdstr, c->name) == 0) 2789 break; 2790 } 2791 if (c->name == NULL) { 2792 NG_FREE_MSG(resp); 2793 error = ENOSYS; 2794 break; 2795 } 2796 } 2797 2798 /* Convert command name to binary */ 2799 binary->header.cmd = c->cmd; 2800 binary->header.typecookie = c->cookie; 2801 2802 /* Convert command arguments to binary */ 2803 argstype = (binary->header.flags & NGF_RESP) ? 2804 c->respType : c->mesgType; 2805 if (argstype == NULL) { 2806 bufSize = 0; 2807 } else { 2808 if ((error = ng_parse(argstype, ascii->data, 2809 &off, (u_char *)binary->data, &bufSize)) != 0) { 2810 NG_FREE_MSG(resp); 2811 break; 2812 } 2813 } 2814 2815 /* Return the result */ 2816 binary->header.arglen = bufSize; 2817 resp->header.arglen = sizeof(*binary) + bufSize; 2818 break; 2819 } 2820 2821 case NGM_TEXT_CONFIG: 2822 case NGM_TEXT_STATUS: 2823 /* 2824 * This one is tricky as it passes the command down to the 2825 * actual node, even though it is a generic type command. 2826 * This means we must assume that the item/msg is already freed 2827 * when control passes back to us. 2828 */ 2829 if (here->nd_type->rcvmsg != NULL) { 2830 NGI_MSG(item) = msg; /* put it back as we found it */ 2831 return((*here->nd_type->rcvmsg)(here, item, lasthook)); 2832 } 2833 /* Fall through if rcvmsg not supported */ 2834 default: 2835 TRAP_ERROR(); 2836 error = EINVAL; 2837 } 2838 /* 2839 * Sometimes a generic message may be statically allocated 2840 * to avoid problems with allocating when in tight memeory situations. 2841 * Don't free it if it is so. 2842 * I break them appart here, because erros may cause a free if the item 2843 * in which case we'd be doing it twice. 2844 * they are kept together above, to simplify freeing. 2845 */ 2846 out: 2847 NG_RESPOND_MSG(error, here, item, resp); 2848 NG_FREE_MSG(msg); 2849 return (error); 2850 } 2851 2852 /************************************************************************ 2853 Queue element get/free routines 2854 ************************************************************************/ 2855 2856 uma_zone_t ng_qzone; 2857 uma_zone_t ng_qdzone; 2858 static int numthreads = 0; /* number of queue threads */ 2859 static int maxalloc = 4096;/* limit the damage of a leak */ 2860 static int maxdata = 512; /* limit the damage of a DoS */ 2861 2862 TUNABLE_INT("net.graph.threads", &numthreads); 2863 SYSCTL_INT(_net_graph, OID_AUTO, threads, CTLFLAG_RDTUN, &numthreads, 2864 0, "Number of queue processing threads"); 2865 TUNABLE_INT("net.graph.maxalloc", &maxalloc); 2866 SYSCTL_INT(_net_graph, OID_AUTO, maxalloc, CTLFLAG_RDTUN, &maxalloc, 2867 0, "Maximum number of non-data queue items to allocate"); 2868 TUNABLE_INT("net.graph.maxdata", &maxdata); 2869 SYSCTL_INT(_net_graph, OID_AUTO, maxdata, CTLFLAG_RDTUN, &maxdata, 2870 0, "Maximum number of data queue items to allocate"); 2871 2872 #ifdef NETGRAPH_DEBUG 2873 static TAILQ_HEAD(, ng_item) ng_itemlist = TAILQ_HEAD_INITIALIZER(ng_itemlist); 2874 static int allocated; /* number of items malloc'd */ 2875 #endif 2876 2877 /* 2878 * Get a queue entry. 2879 * This is usually called when a packet first enters netgraph. 2880 * By definition, this is usually from an interrupt, or from a user. 2881 * Users are not so important, but try be quick for the times that it's 2882 * an interrupt. 2883 */ 2884 static __inline item_p 2885 ng_alloc_item(int type, int flags) 2886 { 2887 item_p item; 2888 2889 KASSERT(((type & ~NGQF_TYPE) == 0), 2890 ("%s: incorrect item type: %d", __func__, type)); 2891 2892 item = uma_zalloc((type == NGQF_DATA)?ng_qdzone:ng_qzone, 2893 ((flags & NG_WAITOK) ? M_WAITOK : M_NOWAIT) | M_ZERO); 2894 2895 if (item) { 2896 item->el_flags = type; 2897 #ifdef NETGRAPH_DEBUG 2898 mtx_lock(&ngq_mtx); 2899 TAILQ_INSERT_TAIL(&ng_itemlist, item, all); 2900 allocated++; 2901 mtx_unlock(&ngq_mtx); 2902 #endif 2903 } 2904 2905 return (item); 2906 } 2907 2908 /* 2909 * Release a queue entry 2910 */ 2911 void 2912 ng_free_item(item_p item) 2913 { 2914 /* 2915 * The item may hold resources on it's own. We need to free 2916 * these before we can free the item. What they are depends upon 2917 * what kind of item it is. it is important that nodes zero 2918 * out pointers to resources that they remove from the item 2919 * or we release them again here. 2920 */ 2921 switch (item->el_flags & NGQF_TYPE) { 2922 case NGQF_DATA: 2923 /* If we have an mbuf still attached.. */ 2924 NG_FREE_M(_NGI_M(item)); 2925 break; 2926 case NGQF_MESG: 2927 _NGI_RETADDR(item) = 0; 2928 NG_FREE_MSG(_NGI_MSG(item)); 2929 break; 2930 case NGQF_FN: 2931 case NGQF_FN2: 2932 /* nothing to free really, */ 2933 _NGI_FN(item) = NULL; 2934 _NGI_ARG1(item) = NULL; 2935 _NGI_ARG2(item) = 0; 2936 break; 2937 } 2938 /* If we still have a node or hook referenced... */ 2939 _NGI_CLR_NODE(item); 2940 _NGI_CLR_HOOK(item); 2941 2942 #ifdef NETGRAPH_DEBUG 2943 mtx_lock(&ngq_mtx); 2944 TAILQ_REMOVE(&ng_itemlist, item, all); 2945 allocated--; 2946 mtx_unlock(&ngq_mtx); 2947 #endif 2948 uma_zfree(((item->el_flags & NGQF_TYPE) == NGQF_DATA)? 2949 ng_qdzone:ng_qzone, item); 2950 } 2951 2952 /* 2953 * Change type of the queue entry. 2954 * Possibly reallocates it from another UMA zone. 2955 */ 2956 static __inline item_p 2957 ng_realloc_item(item_p pitem, int type, int flags) 2958 { 2959 item_p item; 2960 int from, to; 2961 2962 KASSERT((pitem != NULL), ("%s: can't reallocate NULL", __func__)); 2963 KASSERT(((type & ~NGQF_TYPE) == 0), 2964 ("%s: incorrect item type: %d", __func__, type)); 2965 2966 from = ((pitem->el_flags & NGQF_TYPE) == NGQF_DATA); 2967 to = (type == NGQF_DATA); 2968 if (from != to) { 2969 /* If reallocation is required do it and copy item. */ 2970 if ((item = ng_alloc_item(type, flags)) == NULL) { 2971 ng_free_item(pitem); 2972 return (NULL); 2973 } 2974 *item = *pitem; 2975 ng_free_item(pitem); 2976 } else 2977 item = pitem; 2978 item->el_flags = (item->el_flags & ~NGQF_TYPE) | type; 2979 2980 return (item); 2981 } 2982 2983 /************************************************************************ 2984 Module routines 2985 ************************************************************************/ 2986 2987 /* 2988 * Handle the loading/unloading of a netgraph node type module 2989 */ 2990 int 2991 ng_mod_event(module_t mod, int event, void *data) 2992 { 2993 struct ng_type *const type = data; 2994 int s, error = 0; 2995 2996 switch (event) { 2997 case MOD_LOAD: 2998 2999 /* Register new netgraph node type */ 3000 s = splnet(); 3001 if ((error = ng_newtype(type)) != 0) { 3002 splx(s); 3003 break; 3004 } 3005 3006 /* Call type specific code */ 3007 if (type->mod_event != NULL) 3008 if ((error = (*type->mod_event)(mod, event, data))) { 3009 mtx_lock(&ng_typelist_mtx); 3010 type->refs--; /* undo it */ 3011 LIST_REMOVE(type, types); 3012 mtx_unlock(&ng_typelist_mtx); 3013 } 3014 splx(s); 3015 break; 3016 3017 case MOD_UNLOAD: 3018 s = splnet(); 3019 if (type->refs > 1) { /* make sure no nodes exist! */ 3020 error = EBUSY; 3021 } else { 3022 if (type->refs == 0) { 3023 /* failed load, nothing to undo */ 3024 splx(s); 3025 break; 3026 } 3027 if (type->mod_event != NULL) { /* check with type */ 3028 error = (*type->mod_event)(mod, event, data); 3029 if (error != 0) { /* type refuses.. */ 3030 splx(s); 3031 break; 3032 } 3033 } 3034 mtx_lock(&ng_typelist_mtx); 3035 LIST_REMOVE(type, types); 3036 mtx_unlock(&ng_typelist_mtx); 3037 } 3038 splx(s); 3039 break; 3040 3041 default: 3042 if (type->mod_event != NULL) 3043 error = (*type->mod_event)(mod, event, data); 3044 else 3045 error = EOPNOTSUPP; /* XXX ? */ 3046 break; 3047 } 3048 return (error); 3049 } 3050 3051 #ifdef VIMAGE 3052 static void 3053 vnet_netgraph_uninit(const void *unused __unused) 3054 { 3055 node_p node = NULL, last_killed = NULL; 3056 int i; 3057 3058 do { 3059 /* Find a node to kill */ 3060 mtx_lock(&ng_namehash_mtx); 3061 for (i = 0; i < NG_NAME_HASH_SIZE; i++) { 3062 LIST_FOREACH(node, &V_ng_name_hash[i], nd_nodes) { 3063 if (node != &ng_deadnode) { 3064 NG_NODE_REF(node); 3065 break; 3066 } 3067 } 3068 if (node != NULL) 3069 break; 3070 } 3071 mtx_unlock(&ng_namehash_mtx); 3072 3073 /* Attempt to kill it only if it is a regular node */ 3074 if (node != NULL) { 3075 if (node == last_killed) { 3076 /* This should never happen */ 3077 printf("ng node %s needs" 3078 "NGF_REALLY_DIE\n", node->nd_name); 3079 if (node->nd_flags & NGF_REALLY_DIE) 3080 panic("ng node %s won't die", 3081 node->nd_name); 3082 node->nd_flags |= NGF_REALLY_DIE; 3083 } 3084 ng_rmnode(node, NULL, NULL, 0); 3085 NG_NODE_UNREF(node); 3086 last_killed = node; 3087 } 3088 } while (node != NULL); 3089 } 3090 VNET_SYSUNINIT(vnet_netgraph_uninit, SI_SUB_PROTO_IFATTACHDOMAIN, SI_ORDER_ANY, 3091 vnet_netgraph_uninit, NULL); 3092 #endif /* VIMAGE */ 3093 3094 /* 3095 * Handle loading and unloading for this code. 3096 * The only thing we need to link into is the NETISR strucure. 3097 */ 3098 static int 3099 ngb_mod_event(module_t mod, int event, void *data) 3100 { 3101 struct proc *p; 3102 struct thread *td; 3103 int i, error = 0; 3104 3105 switch (event) { 3106 case MOD_LOAD: 3107 /* Initialize everything. */ 3108 NG_WORKLIST_LOCK_INIT(); 3109 mtx_init(&ng_typelist_mtx, "netgraph types mutex", NULL, 3110 MTX_DEF); 3111 mtx_init(&ng_idhash_mtx, "netgraph idhash mutex", NULL, 3112 MTX_DEF); 3113 mtx_init(&ng_namehash_mtx, "netgraph namehash mutex", NULL, 3114 MTX_DEF); 3115 mtx_init(&ng_topo_mtx, "netgraph topology mutex", NULL, 3116 MTX_DEF); 3117 #ifdef NETGRAPH_DEBUG 3118 mtx_init(&ng_nodelist_mtx, "netgraph nodelist mutex", NULL, 3119 MTX_DEF); 3120 mtx_init(&ngq_mtx, "netgraph item list mutex", NULL, 3121 MTX_DEF); 3122 #endif 3123 ng_qzone = uma_zcreate("NetGraph items", sizeof(struct ng_item), 3124 NULL, NULL, NULL, NULL, UMA_ALIGN_CACHE, 0); 3125 uma_zone_set_max(ng_qzone, maxalloc); 3126 ng_qdzone = uma_zcreate("NetGraph data items", sizeof(struct ng_item), 3127 NULL, NULL, NULL, NULL, UMA_ALIGN_CACHE, 0); 3128 uma_zone_set_max(ng_qdzone, maxdata); 3129 /* Autoconfigure number of threads. */ 3130 if (numthreads <= 0) 3131 numthreads = mp_ncpus; 3132 /* Create threads. */ 3133 p = NULL; /* start with no process */ 3134 for (i = 0; i < numthreads; i++) { 3135 if (kproc_kthread_add(ngthread, NULL, &p, &td, 3136 RFHIGHPID, 0, "ng_queue", "ng_queue%d", i)) { 3137 numthreads = i; 3138 break; 3139 } 3140 } 3141 break; 3142 case MOD_UNLOAD: 3143 /* You can't unload it because an interface may be using it. */ 3144 error = EBUSY; 3145 break; 3146 default: 3147 error = EOPNOTSUPP; 3148 break; 3149 } 3150 return (error); 3151 } 3152 3153 static moduledata_t netgraph_mod = { 3154 "netgraph", 3155 ngb_mod_event, 3156 (NULL) 3157 }; 3158 DECLARE_MODULE(netgraph, netgraph_mod, SI_SUB_NETGRAPH, SI_ORDER_MIDDLE); 3159 SYSCTL_NODE(_net, OID_AUTO, graph, CTLFLAG_RW, 0, "netgraph Family"); 3160 SYSCTL_INT(_net_graph, OID_AUTO, abi_version, CTLFLAG_RD, 0, NG_ABI_VERSION,""); 3161 SYSCTL_INT(_net_graph, OID_AUTO, msg_version, CTLFLAG_RD, 0, NG_VERSION, ""); 3162 3163 #ifdef NETGRAPH_DEBUG 3164 void 3165 dumphook (hook_p hook, char *file, int line) 3166 { 3167 printf("hook: name %s, %d refs, Last touched:\n", 3168 _NG_HOOK_NAME(hook), hook->hk_refs); 3169 printf(" Last active @ %s, line %d\n", 3170 hook->lastfile, hook->lastline); 3171 if (line) { 3172 printf(" problem discovered at file %s, line %d\n", file, line); 3173 #ifdef KDB 3174 kdb_backtrace(); 3175 #endif 3176 } 3177 } 3178 3179 void 3180 dumpnode(node_p node, char *file, int line) 3181 { 3182 printf("node: ID [%x]: type '%s', %d hooks, flags 0x%x, %d refs, %s:\n", 3183 _NG_NODE_ID(node), node->nd_type->name, 3184 node->nd_numhooks, node->nd_flags, 3185 node->nd_refs, node->nd_name); 3186 printf(" Last active @ %s, line %d\n", 3187 node->lastfile, node->lastline); 3188 if (line) { 3189 printf(" problem discovered at file %s, line %d\n", file, line); 3190 #ifdef KDB 3191 kdb_backtrace(); 3192 #endif 3193 } 3194 } 3195 3196 void 3197 dumpitem(item_p item, char *file, int line) 3198 { 3199 printf(" ACTIVE item, last used at %s, line %d", 3200 item->lastfile, item->lastline); 3201 switch(item->el_flags & NGQF_TYPE) { 3202 case NGQF_DATA: 3203 printf(" - [data]\n"); 3204 break; 3205 case NGQF_MESG: 3206 printf(" - retaddr[%d]:\n", _NGI_RETADDR(item)); 3207 break; 3208 case NGQF_FN: 3209 printf(" - fn@%p (%p, %p, %p, %d (%x))\n", 3210 _NGI_FN(item), 3211 _NGI_NODE(item), 3212 _NGI_HOOK(item), 3213 item->body.fn.fn_arg1, 3214 item->body.fn.fn_arg2, 3215 item->body.fn.fn_arg2); 3216 break; 3217 case NGQF_FN2: 3218 printf(" - fn2@%p (%p, %p, %p, %d (%x))\n", 3219 _NGI_FN2(item), 3220 _NGI_NODE(item), 3221 _NGI_HOOK(item), 3222 item->body.fn.fn_arg1, 3223 item->body.fn.fn_arg2, 3224 item->body.fn.fn_arg2); 3225 break; 3226 } 3227 if (line) { 3228 printf(" problem discovered at file %s, line %d\n", file, line); 3229 if (_NGI_NODE(item)) { 3230 printf("node %p ([%x])\n", 3231 _NGI_NODE(item), ng_node2ID(_NGI_NODE(item))); 3232 } 3233 } 3234 } 3235 3236 static void 3237 ng_dumpitems(void) 3238 { 3239 item_p item; 3240 int i = 1; 3241 TAILQ_FOREACH(item, &ng_itemlist, all) { 3242 printf("[%d] ", i++); 3243 dumpitem(item, NULL, 0); 3244 } 3245 } 3246 3247 static void 3248 ng_dumpnodes(void) 3249 { 3250 node_p node; 3251 int i = 1; 3252 mtx_lock(&ng_nodelist_mtx); 3253 SLIST_FOREACH(node, &ng_allnodes, nd_all) { 3254 printf("[%d] ", i++); 3255 dumpnode(node, NULL, 0); 3256 } 3257 mtx_unlock(&ng_nodelist_mtx); 3258 } 3259 3260 static void 3261 ng_dumphooks(void) 3262 { 3263 hook_p hook; 3264 int i = 1; 3265 mtx_lock(&ng_nodelist_mtx); 3266 SLIST_FOREACH(hook, &ng_allhooks, hk_all) { 3267 printf("[%d] ", i++); 3268 dumphook(hook, NULL, 0); 3269 } 3270 mtx_unlock(&ng_nodelist_mtx); 3271 } 3272 3273 static int 3274 sysctl_debug_ng_dump_items(SYSCTL_HANDLER_ARGS) 3275 { 3276 int error; 3277 int val; 3278 int i; 3279 3280 val = allocated; 3281 i = 1; 3282 error = sysctl_handle_int(oidp, &val, 0, req); 3283 if (error != 0 || req->newptr == NULL) 3284 return (error); 3285 if (val == 42) { 3286 ng_dumpitems(); 3287 ng_dumpnodes(); 3288 ng_dumphooks(); 3289 } 3290 return (0); 3291 } 3292 3293 SYSCTL_PROC(_debug, OID_AUTO, ng_dump_items, CTLTYPE_INT | CTLFLAG_RW, 3294 0, sizeof(int), sysctl_debug_ng_dump_items, "I", "Number of allocated items"); 3295 #endif /* NETGRAPH_DEBUG */ 3296 3297 3298 /*********************************************************************** 3299 * Worklist routines 3300 **********************************************************************/ 3301 /* 3302 * Pick a node off the list of nodes with work, 3303 * try get an item to process off it. Remove the node from the list. 3304 */ 3305 static void 3306 ngthread(void *arg) 3307 { 3308 for (;;) { 3309 node_p node; 3310 3311 /* Get node from the worklist. */ 3312 NG_WORKLIST_LOCK(); 3313 while ((node = STAILQ_FIRST(&ng_worklist)) == NULL) 3314 NG_WORKLIST_SLEEP(); 3315 STAILQ_REMOVE_HEAD(&ng_worklist, nd_input_queue.q_work); 3316 NG_WORKLIST_UNLOCK(); 3317 CURVNET_SET(node->nd_vnet); 3318 CTR3(KTR_NET, "%20s: node [%x] (%p) taken off worklist", 3319 __func__, node->nd_ID, node); 3320 /* 3321 * We have the node. We also take over the reference 3322 * that the list had on it. 3323 * Now process as much as you can, until it won't 3324 * let you have another item off the queue. 3325 * All this time, keep the reference 3326 * that lets us be sure that the node still exists. 3327 * Let the reference go at the last minute. 3328 */ 3329 for (;;) { 3330 item_p item; 3331 int rw; 3332 3333 NG_QUEUE_LOCK(&node->nd_input_queue); 3334 item = ng_dequeue(node, &rw); 3335 if (item == NULL) { 3336 node->nd_input_queue.q_flags2 &= ~NGQ2_WORKQ; 3337 NG_QUEUE_UNLOCK(&node->nd_input_queue); 3338 break; /* go look for another node */ 3339 } else { 3340 NG_QUEUE_UNLOCK(&node->nd_input_queue); 3341 NGI_GET_NODE(item, node); /* zaps stored node */ 3342 ng_apply_item(node, item, rw); 3343 NG_NODE_UNREF(node); 3344 } 3345 } 3346 NG_NODE_UNREF(node); 3347 CURVNET_RESTORE(); 3348 } 3349 } 3350 3351 /* 3352 * XXX 3353 * It's posible that a debugging NG_NODE_REF may need 3354 * to be outside the mutex zone 3355 */ 3356 static void 3357 ng_worklist_add(node_p node) 3358 { 3359 3360 mtx_assert(&node->nd_input_queue.q_mtx, MA_OWNED); 3361 3362 if ((node->nd_input_queue.q_flags2 & NGQ2_WORKQ) == 0) { 3363 /* 3364 * If we are not already on the work queue, 3365 * then put us on. 3366 */ 3367 node->nd_input_queue.q_flags2 |= NGQ2_WORKQ; 3368 NG_NODE_REF(node); /* XXX fafe in mutex? */ 3369 NG_WORKLIST_LOCK(); 3370 STAILQ_INSERT_TAIL(&ng_worklist, node, nd_input_queue.q_work); 3371 NG_WORKLIST_UNLOCK(); 3372 CTR3(KTR_NET, "%20s: node [%x] (%p) put on worklist", __func__, 3373 node->nd_ID, node); 3374 NG_WORKLIST_WAKEUP(); 3375 } else { 3376 CTR3(KTR_NET, "%20s: node [%x] (%p) already on worklist", 3377 __func__, node->nd_ID, node); 3378 } 3379 } 3380 3381 3382 /*********************************************************************** 3383 * Externally useable functions to set up a queue item ready for sending 3384 ***********************************************************************/ 3385 3386 #ifdef NETGRAPH_DEBUG 3387 #define ITEM_DEBUG_CHECKS \ 3388 do { \ 3389 if (NGI_NODE(item) ) { \ 3390 printf("item already has node"); \ 3391 kdb_enter(KDB_WHY_NETGRAPH, "has node"); \ 3392 NGI_CLR_NODE(item); \ 3393 } \ 3394 if (NGI_HOOK(item) ) { \ 3395 printf("item already has hook"); \ 3396 kdb_enter(KDB_WHY_NETGRAPH, "has hook"); \ 3397 NGI_CLR_HOOK(item); \ 3398 } \ 3399 } while (0) 3400 #else 3401 #define ITEM_DEBUG_CHECKS 3402 #endif 3403 3404 /* 3405 * Put mbuf into the item. 3406 * Hook and node references will be removed when the item is dequeued. 3407 * (or equivalent) 3408 * (XXX) Unsafe because no reference held by peer on remote node. 3409 * remote node might go away in this timescale. 3410 * We know the hooks can't go away because that would require getting 3411 * a writer item on both nodes and we must have at least a reader 3412 * here to be able to do this. 3413 * Note that the hook loaded is the REMOTE hook. 3414 * 3415 * This is possibly in the critical path for new data. 3416 */ 3417 item_p 3418 ng_package_data(struct mbuf *m, int flags) 3419 { 3420 item_p item; 3421 3422 if ((item = ng_alloc_item(NGQF_DATA, flags)) == NULL) { 3423 NG_FREE_M(m); 3424 return (NULL); 3425 } 3426 ITEM_DEBUG_CHECKS; 3427 item->el_flags |= NGQF_READER; 3428 NGI_M(item) = m; 3429 return (item); 3430 } 3431 3432 /* 3433 * Allocate a queue item and put items into it.. 3434 * Evaluate the address as this will be needed to queue it and 3435 * to work out what some of the fields should be. 3436 * Hook and node references will be removed when the item is dequeued. 3437 * (or equivalent) 3438 */ 3439 item_p 3440 ng_package_msg(struct ng_mesg *msg, int flags) 3441 { 3442 item_p item; 3443 3444 if ((item = ng_alloc_item(NGQF_MESG, flags)) == NULL) { 3445 NG_FREE_MSG(msg); 3446 return (NULL); 3447 } 3448 ITEM_DEBUG_CHECKS; 3449 /* Messages items count as writers unless explicitly exempted. */ 3450 if (msg->header.cmd & NGM_READONLY) 3451 item->el_flags |= NGQF_READER; 3452 else 3453 item->el_flags |= NGQF_WRITER; 3454 /* 3455 * Set the current lasthook into the queue item 3456 */ 3457 NGI_MSG(item) = msg; 3458 NGI_RETADDR(item) = 0; 3459 return (item); 3460 } 3461 3462 3463 3464 #define SET_RETADDR(item, here, retaddr) \ 3465 do { /* Data or fn items don't have retaddrs */ \ 3466 if ((item->el_flags & NGQF_TYPE) == NGQF_MESG) { \ 3467 if (retaddr) { \ 3468 NGI_RETADDR(item) = retaddr; \ 3469 } else { \ 3470 /* \ 3471 * The old return address should be ok. \ 3472 * If there isn't one, use the address \ 3473 * here. \ 3474 */ \ 3475 if (NGI_RETADDR(item) == 0) { \ 3476 NGI_RETADDR(item) \ 3477 = ng_node2ID(here); \ 3478 } \ 3479 } \ 3480 } \ 3481 } while (0) 3482 3483 int 3484 ng_address_hook(node_p here, item_p item, hook_p hook, ng_ID_t retaddr) 3485 { 3486 hook_p peer; 3487 node_p peernode; 3488 ITEM_DEBUG_CHECKS; 3489 /* 3490 * Quick sanity check.. 3491 * Since a hook holds a reference on it's node, once we know 3492 * that the peer is still connected (even if invalid,) we know 3493 * that the peer node is present, though maybe invalid. 3494 */ 3495 mtx_lock(&ng_topo_mtx); 3496 if ((hook == NULL) || 3497 NG_HOOK_NOT_VALID(hook) || 3498 NG_HOOK_NOT_VALID(peer = NG_HOOK_PEER(hook)) || 3499 NG_NODE_NOT_VALID(peernode = NG_PEER_NODE(hook))) { 3500 NG_FREE_ITEM(item); 3501 TRAP_ERROR(); 3502 mtx_unlock(&ng_topo_mtx); 3503 return (ENETDOWN); 3504 } 3505 3506 /* 3507 * Transfer our interest to the other (peer) end. 3508 */ 3509 NG_HOOK_REF(peer); 3510 NG_NODE_REF(peernode); 3511 NGI_SET_HOOK(item, peer); 3512 NGI_SET_NODE(item, peernode); 3513 SET_RETADDR(item, here, retaddr); 3514 3515 mtx_unlock(&ng_topo_mtx); 3516 3517 return (0); 3518 } 3519 3520 int 3521 ng_address_path(node_p here, item_p item, const char *address, ng_ID_t retaddr) 3522 { 3523 node_p dest = NULL; 3524 hook_p hook = NULL; 3525 int error; 3526 3527 ITEM_DEBUG_CHECKS; 3528 /* 3529 * Note that ng_path2noderef increments the reference count 3530 * on the node for us if it finds one. So we don't have to. 3531 */ 3532 error = ng_path2noderef(here, address, &dest, &hook); 3533 if (error) { 3534 NG_FREE_ITEM(item); 3535 return (error); 3536 } 3537 NGI_SET_NODE(item, dest); 3538 if (hook) 3539 NGI_SET_HOOK(item, hook); 3540 3541 SET_RETADDR(item, here, retaddr); 3542 return (0); 3543 } 3544 3545 int 3546 ng_address_ID(node_p here, item_p item, ng_ID_t ID, ng_ID_t retaddr) 3547 { 3548 node_p dest; 3549 3550 ITEM_DEBUG_CHECKS; 3551 /* 3552 * Find the target node. 3553 */ 3554 dest = ng_ID2noderef(ID); /* GETS REFERENCE! */ 3555 if (dest == NULL) { 3556 NG_FREE_ITEM(item); 3557 TRAP_ERROR(); 3558 return(EINVAL); 3559 } 3560 /* Fill out the contents */ 3561 NGI_SET_NODE(item, dest); 3562 NGI_CLR_HOOK(item); 3563 SET_RETADDR(item, here, retaddr); 3564 return (0); 3565 } 3566 3567 /* 3568 * special case to send a message to self (e.g. destroy node) 3569 * Possibly indicate an arrival hook too. 3570 * Useful for removing that hook :-) 3571 */ 3572 item_p 3573 ng_package_msg_self(node_p here, hook_p hook, struct ng_mesg *msg) 3574 { 3575 item_p item; 3576 3577 /* 3578 * Find the target node. 3579 * If there is a HOOK argument, then use that in preference 3580 * to the address. 3581 */ 3582 if ((item = ng_alloc_item(NGQF_MESG, NG_NOFLAGS)) == NULL) { 3583 NG_FREE_MSG(msg); 3584 return (NULL); 3585 } 3586 3587 /* Fill out the contents */ 3588 item->el_flags |= NGQF_WRITER; 3589 NG_NODE_REF(here); 3590 NGI_SET_NODE(item, here); 3591 if (hook) { 3592 NG_HOOK_REF(hook); 3593 NGI_SET_HOOK(item, hook); 3594 } 3595 NGI_MSG(item) = msg; 3596 NGI_RETADDR(item) = ng_node2ID(here); 3597 return (item); 3598 } 3599 3600 /* 3601 * Send ng_item_fn function call to the specified node. 3602 */ 3603 3604 int 3605 ng_send_fn(node_p node, hook_p hook, ng_item_fn *fn, void * arg1, int arg2) 3606 { 3607 3608 return ng_send_fn1(node, hook, fn, arg1, arg2, NG_NOFLAGS); 3609 } 3610 3611 int 3612 ng_send_fn1(node_p node, hook_p hook, ng_item_fn *fn, void * arg1, int arg2, 3613 int flags) 3614 { 3615 item_p item; 3616 3617 if ((item = ng_alloc_item(NGQF_FN, flags)) == NULL) { 3618 return (ENOMEM); 3619 } 3620 item->el_flags |= NGQF_WRITER; 3621 NG_NODE_REF(node); /* and one for the item */ 3622 NGI_SET_NODE(item, node); 3623 if (hook) { 3624 NG_HOOK_REF(hook); 3625 NGI_SET_HOOK(item, hook); 3626 } 3627 NGI_FN(item) = fn; 3628 NGI_ARG1(item) = arg1; 3629 NGI_ARG2(item) = arg2; 3630 return(ng_snd_item(item, flags)); 3631 } 3632 3633 /* 3634 * Send ng_item_fn2 function call to the specified node. 3635 * 3636 * If an optional pitem parameter is supplied, its apply 3637 * callback will be copied to the new item. If also NG_REUSE_ITEM 3638 * flag is set, no new item will be allocated, but pitem will 3639 * be used. 3640 */ 3641 int 3642 ng_send_fn2(node_p node, hook_p hook, item_p pitem, ng_item_fn2 *fn, void *arg1, 3643 int arg2, int flags) 3644 { 3645 item_p item; 3646 3647 KASSERT((pitem != NULL || (flags & NG_REUSE_ITEM) == 0), 3648 ("%s: NG_REUSE_ITEM but no pitem", __func__)); 3649 3650 /* 3651 * Allocate a new item if no supplied or 3652 * if we can't use supplied one. 3653 */ 3654 if (pitem == NULL || (flags & NG_REUSE_ITEM) == 0) { 3655 if ((item = ng_alloc_item(NGQF_FN2, flags)) == NULL) 3656 return (ENOMEM); 3657 if (pitem != NULL) 3658 item->apply = pitem->apply; 3659 } else { 3660 if ((item = ng_realloc_item(pitem, NGQF_FN2, flags)) == NULL) 3661 return (ENOMEM); 3662 } 3663 3664 item->el_flags = (item->el_flags & ~NGQF_RW) | NGQF_WRITER; 3665 NG_NODE_REF(node); /* and one for the item */ 3666 NGI_SET_NODE(item, node); 3667 if (hook) { 3668 NG_HOOK_REF(hook); 3669 NGI_SET_HOOK(item, hook); 3670 } 3671 NGI_FN2(item) = fn; 3672 NGI_ARG1(item) = arg1; 3673 NGI_ARG2(item) = arg2; 3674 return(ng_snd_item(item, flags)); 3675 } 3676 3677 /* 3678 * Official timeout routines for Netgraph nodes. 3679 */ 3680 static void 3681 ng_callout_trampoline(void *arg) 3682 { 3683 item_p item = arg; 3684 3685 CURVNET_SET(NGI_NODE(item)->nd_vnet); 3686 ng_snd_item(item, 0); 3687 CURVNET_RESTORE(); 3688 } 3689 3690 3691 int 3692 ng_callout(struct callout *c, node_p node, hook_p hook, int ticks, 3693 ng_item_fn *fn, void * arg1, int arg2) 3694 { 3695 item_p item, oitem; 3696 3697 if ((item = ng_alloc_item(NGQF_FN, NG_NOFLAGS)) == NULL) 3698 return (ENOMEM); 3699 3700 item->el_flags |= NGQF_WRITER; 3701 NG_NODE_REF(node); /* and one for the item */ 3702 NGI_SET_NODE(item, node); 3703 if (hook) { 3704 NG_HOOK_REF(hook); 3705 NGI_SET_HOOK(item, hook); 3706 } 3707 NGI_FN(item) = fn; 3708 NGI_ARG1(item) = arg1; 3709 NGI_ARG2(item) = arg2; 3710 oitem = c->c_arg; 3711 if (callout_reset(c, ticks, &ng_callout_trampoline, item) == 1 && 3712 oitem != NULL) 3713 NG_FREE_ITEM(oitem); 3714 return (0); 3715 } 3716 3717 /* A special modified version of untimeout() */ 3718 int 3719 ng_uncallout(struct callout *c, node_p node) 3720 { 3721 item_p item; 3722 int rval; 3723 3724 KASSERT(c != NULL, ("ng_uncallout: NULL callout")); 3725 KASSERT(node != NULL, ("ng_uncallout: NULL node")); 3726 3727 rval = callout_stop(c); 3728 item = c->c_arg; 3729 /* Do an extra check */ 3730 if ((rval > 0) && (c->c_func == &ng_callout_trampoline) && 3731 (NGI_NODE(item) == node)) { 3732 /* 3733 * We successfully removed it from the queue before it ran 3734 * So now we need to unreference everything that was 3735 * given extra references. (NG_FREE_ITEM does this). 3736 */ 3737 NG_FREE_ITEM(item); 3738 } 3739 c->c_arg = NULL; 3740 3741 return (rval); 3742 } 3743 3744 /* 3745 * Set the address, if none given, give the node here. 3746 */ 3747 void 3748 ng_replace_retaddr(node_p here, item_p item, ng_ID_t retaddr) 3749 { 3750 if (retaddr) { 3751 NGI_RETADDR(item) = retaddr; 3752 } else { 3753 /* 3754 * The old return address should be ok. 3755 * If there isn't one, use the address here. 3756 */ 3757 NGI_RETADDR(item) = ng_node2ID(here); 3758 } 3759 } 3760 3761 #define TESTING 3762 #ifdef TESTING 3763 /* just test all the macros */ 3764 void 3765 ng_macro_test(item_p item); 3766 void 3767 ng_macro_test(item_p item) 3768 { 3769 node_p node = NULL; 3770 hook_p hook = NULL; 3771 struct mbuf *m; 3772 struct ng_mesg *msg; 3773 ng_ID_t retaddr; 3774 int error; 3775 3776 NGI_GET_M(item, m); 3777 NGI_GET_MSG(item, msg); 3778 retaddr = NGI_RETADDR(item); 3779 NG_SEND_DATA(error, hook, m, NULL); 3780 NG_SEND_DATA_ONLY(error, hook, m); 3781 NG_FWD_NEW_DATA(error, item, hook, m); 3782 NG_FWD_ITEM_HOOK(error, item, hook); 3783 NG_SEND_MSG_HOOK(error, node, msg, hook, retaddr); 3784 NG_SEND_MSG_ID(error, node, msg, retaddr, retaddr); 3785 NG_SEND_MSG_PATH(error, node, msg, ".:", retaddr); 3786 NG_FWD_MSG_HOOK(error, node, item, hook, retaddr); 3787 } 3788 #endif /* TESTING */ 3789 3790