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/limits.h> 56 #include <sys/malloc.h> 57 #include <sys/mbuf.h> 58 #include <sys/queue.h> 59 #include <sys/sysctl.h> 60 #include <sys/syslog.h> 61 62 #include <net/netisr.h> 63 64 #include <netgraph/ng_message.h> 65 #include <netgraph/netgraph.h> 66 #include <netgraph/ng_parse.h> 67 68 MODULE_VERSION(netgraph, NG_ABI_VERSION); 69 70 /* List of all active nodes */ 71 static LIST_HEAD(, ng_node) ng_nodelist; 72 static struct mtx ng_nodelist_mtx; 73 74 /* Mutex that protects the free queue item list */ 75 static struct mtx ngq_mtx; 76 77 #ifdef NETGRAPH_DEBUG 78 79 static SLIST_HEAD(, ng_node) ng_allnodes; 80 static LIST_HEAD(, ng_node) ng_freenodes; /* in debug, we never free() them */ 81 static SLIST_HEAD(, ng_hook) ng_allhooks; 82 static LIST_HEAD(, ng_hook) ng_freehooks; /* in debug, we never free() them */ 83 84 static void ng_dumpitems(void); 85 static void ng_dumpnodes(void); 86 static void ng_dumphooks(void); 87 88 #endif /* NETGRAPH_DEBUG */ 89 /* 90 * DEAD versions of the structures. 91 * In order to avoid races, it is sometimes neccesary to point 92 * at SOMETHING even though theoretically, the current entity is 93 * INVALID. Use these to avoid these races. 94 */ 95 struct ng_type ng_deadtype = { 96 NG_ABI_VERSION, 97 "dead", 98 NULL, /* modevent */ 99 NULL, /* constructor */ 100 NULL, /* rcvmsg */ 101 NULL, /* shutdown */ 102 NULL, /* newhook */ 103 NULL, /* findhook */ 104 NULL, /* connect */ 105 NULL, /* rcvdata */ 106 NULL, /* disconnect */ 107 NULL, /* cmdlist */ 108 }; 109 110 struct ng_node ng_deadnode = { 111 "dead", 112 &ng_deadtype, 113 NGF_INVALID, 114 1, /* refs */ 115 0, /* numhooks */ 116 NULL, /* private */ 117 0, /* ID */ 118 LIST_HEAD_INITIALIZER(ng_deadnode.hooks), 119 {}, /* all_nodes list entry */ 120 {}, /* id hashtable list entry */ 121 {}, /* workqueue entry */ 122 { 0, 123 {}, /* should never use! (should hang) */ 124 NULL, 125 &ng_deadnode.nd_input_queue.queue, 126 &ng_deadnode 127 }, 128 #ifdef NETGRAPH_DEBUG 129 ND_MAGIC, 130 __FILE__, 131 __LINE__, 132 {NULL} 133 #endif /* NETGRAPH_DEBUG */ 134 }; 135 136 struct ng_hook ng_deadhook = { 137 "dead", 138 NULL, /* private */ 139 HK_INVALID | HK_DEAD, 140 1, /* refs always >= 1 */ 141 &ng_deadhook, /* Peer is self */ 142 &ng_deadnode, /* attached to deadnode */ 143 {}, /* hooks list */ 144 NULL, /* override rcvmsg() */ 145 NULL, /* override rcvdata() */ 146 #ifdef NETGRAPH_DEBUG 147 HK_MAGIC, 148 __FILE__, 149 __LINE__, 150 {NULL} 151 #endif /* NETGRAPH_DEBUG */ 152 }; 153 154 /* 155 * END DEAD STRUCTURES 156 */ 157 /* List nodes with unallocated work */ 158 static TAILQ_HEAD(, ng_node) ng_worklist = TAILQ_HEAD_INITIALIZER(ng_worklist); 159 static struct mtx ng_worklist_mtx; /* MUST LOCK NODE FIRST */ 160 161 /* List of installed types */ 162 static LIST_HEAD(, ng_type) ng_typelist; 163 static struct mtx ng_typelist_mtx; 164 165 /* Hash related definitions */ 166 /* XXX Don't need to initialise them because it's a LIST */ 167 #define NG_ID_HASH_SIZE 32 /* most systems wont need even this many */ 168 static LIST_HEAD(, ng_node) ng_ID_hash[NG_ID_HASH_SIZE]; 169 static struct mtx ng_idhash_mtx; 170 /* Method to find a node.. used twice so do it here */ 171 #define NG_IDHASH_FN(ID) ((ID) % (NG_ID_HASH_SIZE)) 172 #define NG_IDHASH_FIND(ID, node) \ 173 do { \ 174 mtx_assert(&ng_idhash_mtx, MA_OWNED); \ 175 LIST_FOREACH(node, &ng_ID_hash[NG_IDHASH_FN(ID)], \ 176 nd_idnodes) { \ 177 if (NG_NODE_IS_VALID(node) \ 178 && (NG_NODE_ID(node) == ID)) { \ 179 break; \ 180 } \ 181 } \ 182 } while (0) 183 184 185 /* Internal functions */ 186 static int ng_add_hook(node_p node, const char *name, hook_p * hookp); 187 static int ng_generic_msg(node_p here, item_p item, hook_p lasthook); 188 static ng_ID_t ng_decodeidname(const char *name); 189 static int ngb_mod_event(module_t mod, int event, void *data); 190 static void ng_worklist_remove(node_p node); 191 static void ngintr(void); 192 static int ng_apply_item(node_p node, item_p item); 193 static void ng_flush_input_queue(struct ng_queue * ngq); 194 static void ng_setisr(node_p node); 195 static node_p ng_ID2noderef(ng_ID_t ID); 196 static int ng_con_nodes(node_p node, const char *name, node_p node2, 197 const char *name2); 198 static void ng_con_part2(node_p node, hook_p hook, void *arg1, int arg2); 199 static void ng_con_part3(node_p node, hook_p hook, void *arg1, int arg2); 200 static int ng_mkpeer(node_p node, const char *name, 201 const char *name2, char *type); 202 203 /* imported , these used to be externally visible, some may go back */ 204 void ng_destroy_hook(hook_p hook); 205 node_p ng_name2noderef(node_p node, const char *name); 206 int ng_path2noderef(node_p here, const char *path, 207 node_p *dest, hook_p *lasthook); 208 int ng_make_node(const char *type, node_p *nodepp); 209 int ng_path_parse(char *addr, char **node, char **path, char **hook); 210 void ng_rmnode(node_p node, hook_p dummy1, void *dummy2, int dummy3); 211 void ng_unname(node_p node); 212 213 214 /* Our own netgraph malloc type */ 215 MALLOC_DEFINE(M_NETGRAPH, "netgraph", "netgraph structures and ctrl messages"); 216 MALLOC_DEFINE(M_NETGRAPH_HOOK, "netgraph_hook", "netgraph hook structures"); 217 MALLOC_DEFINE(M_NETGRAPH_NODE, "netgraph_node", "netgraph node structures"); 218 MALLOC_DEFINE(M_NETGRAPH_ITEM, "netgraph_item", "netgraph item structures"); 219 MALLOC_DEFINE(M_NETGRAPH_MSG, "netgraph_msg", "netgraph name storage"); 220 221 /* Should not be visible outside this file */ 222 223 #define _NG_ALLOC_HOOK(hook) \ 224 MALLOC(hook, hook_p, sizeof(*hook), M_NETGRAPH_HOOK, M_NOWAIT | M_ZERO) 225 #define _NG_ALLOC_NODE(node) \ 226 MALLOC(node, node_p, sizeof(*node), M_NETGRAPH_NODE, M_NOWAIT | M_ZERO) 227 228 #ifdef NETGRAPH_DEBUG /*----------------------------------------------*/ 229 /* 230 * In debug mode: 231 * In an attempt to help track reference count screwups 232 * we do not free objects back to the malloc system, but keep them 233 * in a local cache where we can examine them and keep information safely 234 * after they have been freed. 235 * We use this scheme for nodes and hooks, and to some extent for items. 236 */ 237 static __inline hook_p 238 ng_alloc_hook(void) 239 { 240 hook_p hook; 241 SLIST_ENTRY(ng_hook) temp; 242 mtx_lock(&ng_nodelist_mtx); 243 hook = LIST_FIRST(&ng_freehooks); 244 if (hook) { 245 LIST_REMOVE(hook, hk_hooks); 246 bcopy(&hook->hk_all, &temp, sizeof(temp)); 247 bzero(hook, sizeof(struct ng_hook)); 248 bcopy(&temp, &hook->hk_all, sizeof(temp)); 249 mtx_unlock(&ng_nodelist_mtx); 250 hook->hk_magic = HK_MAGIC; 251 } else { 252 mtx_unlock(&ng_nodelist_mtx); 253 _NG_ALLOC_HOOK(hook); 254 if (hook) { 255 hook->hk_magic = HK_MAGIC; 256 mtx_lock(&ng_nodelist_mtx); 257 SLIST_INSERT_HEAD(&ng_allhooks, hook, hk_all); 258 mtx_unlock(&ng_nodelist_mtx); 259 } 260 } 261 return (hook); 262 } 263 264 static __inline node_p 265 ng_alloc_node(void) 266 { 267 node_p node; 268 SLIST_ENTRY(ng_node) temp; 269 mtx_lock(&ng_nodelist_mtx); 270 node = LIST_FIRST(&ng_freenodes); 271 if (node) { 272 LIST_REMOVE(node, nd_nodes); 273 bcopy(&node->nd_all, &temp, sizeof(temp)); 274 bzero(node, sizeof(struct ng_node)); 275 bcopy(&temp, &node->nd_all, sizeof(temp)); 276 mtx_unlock(&ng_nodelist_mtx); 277 node->nd_magic = ND_MAGIC; 278 } else { 279 mtx_unlock(&ng_nodelist_mtx); 280 _NG_ALLOC_NODE(node); 281 if (node) { 282 node->nd_magic = ND_MAGIC; 283 mtx_lock(&ng_nodelist_mtx); 284 SLIST_INSERT_HEAD(&ng_allnodes, node, nd_all); 285 mtx_unlock(&ng_nodelist_mtx); 286 } 287 } 288 return (node); 289 } 290 291 #define NG_ALLOC_HOOK(hook) do { (hook) = ng_alloc_hook(); } while (0) 292 #define NG_ALLOC_NODE(node) do { (node) = ng_alloc_node(); } while (0) 293 294 295 #define NG_FREE_HOOK(hook) \ 296 do { \ 297 mtx_lock(&ng_nodelist_mtx); \ 298 LIST_INSERT_HEAD(&ng_freehooks, hook, hk_hooks); \ 299 hook->hk_magic = 0; \ 300 mtx_unlock(&ng_nodelist_mtx); \ 301 } while (0) 302 303 #define NG_FREE_NODE(node) \ 304 do { \ 305 mtx_lock(&ng_nodelist_mtx); \ 306 LIST_INSERT_HEAD(&ng_freenodes, node, nd_nodes); \ 307 node->nd_magic = 0; \ 308 mtx_unlock(&ng_nodelist_mtx); \ 309 } while (0) 310 311 #else /* NETGRAPH_DEBUG */ /*----------------------------------------------*/ 312 313 #define NG_ALLOC_HOOK(hook) _NG_ALLOC_HOOK(hook) 314 #define NG_ALLOC_NODE(node) _NG_ALLOC_NODE(node) 315 316 #define NG_FREE_HOOK(hook) do { FREE((hook), M_NETGRAPH_HOOK); } while (0) 317 #define NG_FREE_NODE(node) do { FREE((node), M_NETGRAPH_NODE); } while (0) 318 319 #endif /* NETGRAPH_DEBUG */ /*----------------------------------------------*/ 320 321 /* Warning: Generally use NG_FREE_ITEM() instead */ 322 #define NG_FREE_ITEM_REAL(item) do { FREE((item), M_NETGRAPH_ITEM); } while (0) 323 324 325 /* Set this to kdb_enter("X") to catch all errors as they occur */ 326 #ifndef TRAP_ERROR 327 #define TRAP_ERROR() 328 #endif 329 330 static ng_ID_t nextID = 1; 331 332 #ifdef INVARIANTS 333 #define CHECK_DATA_MBUF(m) do { \ 334 struct mbuf *n; \ 335 int total; \ 336 \ 337 M_ASSERTPKTHDR(m); \ 338 for (total = 0, n = (m); n != NULL; n = n->m_next) \ 339 total += n->m_len; \ 340 if ((m)->m_pkthdr.len != total) { \ 341 panic("%s: %d != %d", \ 342 __func__, (m)->m_pkthdr.len, total); \ 343 } \ 344 } while (0) 345 #else 346 #define CHECK_DATA_MBUF(m) 347 #endif 348 349 350 /************************************************************************ 351 Parse type definitions for generic messages 352 ************************************************************************/ 353 354 /* Handy structure parse type defining macro */ 355 #define DEFINE_PARSE_STRUCT_TYPE(lo, up, args) \ 356 static const struct ng_parse_struct_field \ 357 ng_ ## lo ## _type_fields[] = NG_GENERIC_ ## up ## _INFO args; \ 358 static const struct ng_parse_type ng_generic_ ## lo ## _type = { \ 359 &ng_parse_struct_type, \ 360 &ng_ ## lo ## _type_fields \ 361 } 362 363 DEFINE_PARSE_STRUCT_TYPE(mkpeer, MKPEER, ()); 364 DEFINE_PARSE_STRUCT_TYPE(connect, CONNECT, ()); 365 DEFINE_PARSE_STRUCT_TYPE(name, NAME, ()); 366 DEFINE_PARSE_STRUCT_TYPE(rmhook, RMHOOK, ()); 367 DEFINE_PARSE_STRUCT_TYPE(nodeinfo, NODEINFO, ()); 368 DEFINE_PARSE_STRUCT_TYPE(typeinfo, TYPEINFO, ()); 369 DEFINE_PARSE_STRUCT_TYPE(linkinfo, LINKINFO, (&ng_generic_nodeinfo_type)); 370 371 /* Get length of an array when the length is stored as a 32 bit 372 value immediately preceding the array -- as with struct namelist 373 and struct typelist. */ 374 static int 375 ng_generic_list_getLength(const struct ng_parse_type *type, 376 const u_char *start, const u_char *buf) 377 { 378 return *((const u_int32_t *)(buf - 4)); 379 } 380 381 /* Get length of the array of struct linkinfo inside a struct hooklist */ 382 static int 383 ng_generic_linkinfo_getLength(const struct ng_parse_type *type, 384 const u_char *start, const u_char *buf) 385 { 386 const struct hooklist *hl = (const struct hooklist *)start; 387 388 return hl->nodeinfo.hooks; 389 } 390 391 /* Array type for a variable length array of struct namelist */ 392 static const struct ng_parse_array_info ng_nodeinfoarray_type_info = { 393 &ng_generic_nodeinfo_type, 394 &ng_generic_list_getLength 395 }; 396 static const struct ng_parse_type ng_generic_nodeinfoarray_type = { 397 &ng_parse_array_type, 398 &ng_nodeinfoarray_type_info 399 }; 400 401 /* Array type for a variable length array of struct typelist */ 402 static const struct ng_parse_array_info ng_typeinfoarray_type_info = { 403 &ng_generic_typeinfo_type, 404 &ng_generic_list_getLength 405 }; 406 static const struct ng_parse_type ng_generic_typeinfoarray_type = { 407 &ng_parse_array_type, 408 &ng_typeinfoarray_type_info 409 }; 410 411 /* Array type for array of struct linkinfo in struct hooklist */ 412 static const struct ng_parse_array_info ng_generic_linkinfo_array_type_info = { 413 &ng_generic_linkinfo_type, 414 &ng_generic_linkinfo_getLength 415 }; 416 static const struct ng_parse_type ng_generic_linkinfo_array_type = { 417 &ng_parse_array_type, 418 &ng_generic_linkinfo_array_type_info 419 }; 420 421 DEFINE_PARSE_STRUCT_TYPE(typelist, TYPELIST, (&ng_generic_nodeinfoarray_type)); 422 DEFINE_PARSE_STRUCT_TYPE(hooklist, HOOKLIST, 423 (&ng_generic_nodeinfo_type, &ng_generic_linkinfo_array_type)); 424 DEFINE_PARSE_STRUCT_TYPE(listnodes, LISTNODES, 425 (&ng_generic_nodeinfoarray_type)); 426 427 /* List of commands and how to convert arguments to/from ASCII */ 428 static const struct ng_cmdlist ng_generic_cmds[] = { 429 { 430 NGM_GENERIC_COOKIE, 431 NGM_SHUTDOWN, 432 "shutdown", 433 NULL, 434 NULL 435 }, 436 { 437 NGM_GENERIC_COOKIE, 438 NGM_MKPEER, 439 "mkpeer", 440 &ng_generic_mkpeer_type, 441 NULL 442 }, 443 { 444 NGM_GENERIC_COOKIE, 445 NGM_CONNECT, 446 "connect", 447 &ng_generic_connect_type, 448 NULL 449 }, 450 { 451 NGM_GENERIC_COOKIE, 452 NGM_NAME, 453 "name", 454 &ng_generic_name_type, 455 NULL 456 }, 457 { 458 NGM_GENERIC_COOKIE, 459 NGM_RMHOOK, 460 "rmhook", 461 &ng_generic_rmhook_type, 462 NULL 463 }, 464 { 465 NGM_GENERIC_COOKIE, 466 NGM_NODEINFO, 467 "nodeinfo", 468 NULL, 469 &ng_generic_nodeinfo_type 470 }, 471 { 472 NGM_GENERIC_COOKIE, 473 NGM_LISTHOOKS, 474 "listhooks", 475 NULL, 476 &ng_generic_hooklist_type 477 }, 478 { 479 NGM_GENERIC_COOKIE, 480 NGM_LISTNAMES, 481 "listnames", 482 NULL, 483 &ng_generic_listnodes_type /* same as NGM_LISTNODES */ 484 }, 485 { 486 NGM_GENERIC_COOKIE, 487 NGM_LISTNODES, 488 "listnodes", 489 NULL, 490 &ng_generic_listnodes_type 491 }, 492 { 493 NGM_GENERIC_COOKIE, 494 NGM_LISTTYPES, 495 "listtypes", 496 NULL, 497 &ng_generic_typeinfo_type 498 }, 499 { 500 NGM_GENERIC_COOKIE, 501 NGM_TEXT_CONFIG, 502 "textconfig", 503 NULL, 504 &ng_parse_string_type 505 }, 506 { 507 NGM_GENERIC_COOKIE, 508 NGM_TEXT_STATUS, 509 "textstatus", 510 NULL, 511 &ng_parse_string_type 512 }, 513 { 514 NGM_GENERIC_COOKIE, 515 NGM_ASCII2BINARY, 516 "ascii2binary", 517 &ng_parse_ng_mesg_type, 518 &ng_parse_ng_mesg_type 519 }, 520 { 521 NGM_GENERIC_COOKIE, 522 NGM_BINARY2ASCII, 523 "binary2ascii", 524 &ng_parse_ng_mesg_type, 525 &ng_parse_ng_mesg_type 526 }, 527 { 0 } 528 }; 529 530 /************************************************************************ 531 Node routines 532 ************************************************************************/ 533 534 /* 535 * Instantiate a node of the requested type 536 */ 537 int 538 ng_make_node(const char *typename, node_p *nodepp) 539 { 540 struct ng_type *type; 541 int error; 542 543 /* Check that the type makes sense */ 544 if (typename == NULL) { 545 TRAP_ERROR(); 546 return (EINVAL); 547 } 548 549 /* Locate the node type. If we fail we return. Do not try to load 550 * module. 551 */ 552 if ((type = ng_findtype(typename)) == NULL) 553 return (ENXIO); 554 555 /* 556 * If we have a constructor, then make the node and 557 * call the constructor to do type specific initialisation. 558 */ 559 if (type->constructor != NULL) { 560 if ((error = ng_make_node_common(type, nodepp)) == 0) { 561 if ((error = ((*type->constructor)(*nodepp)) != 0)) { 562 NG_NODE_UNREF(*nodepp); 563 } 564 } 565 } else { 566 /* 567 * Node has no constructor. We cannot ask for one 568 * to be made. It must be brought into existance by 569 * some external agency. The external agency should 570 * call ng_make_node_common() directly to get the 571 * netgraph part initialised. 572 */ 573 TRAP_ERROR(); 574 error = EINVAL; 575 } 576 return (error); 577 } 578 579 /* 580 * Generic node creation. Called by node initialisation for externally 581 * instantiated nodes (e.g. hardware, sockets, etc ). 582 * The returned node has a reference count of 1. 583 */ 584 int 585 ng_make_node_common(struct ng_type *type, node_p *nodepp) 586 { 587 node_p node; 588 589 /* Require the node type to have been already installed */ 590 if (ng_findtype(type->name) == NULL) { 591 TRAP_ERROR(); 592 return (EINVAL); 593 } 594 595 /* Make a node and try attach it to the type */ 596 NG_ALLOC_NODE(node); 597 if (node == NULL) { 598 TRAP_ERROR(); 599 return (ENOMEM); 600 } 601 node->nd_type = type; 602 NG_NODE_REF(node); /* note reference */ 603 type->refs++; 604 605 mtx_init(&node->nd_input_queue.q_mtx, "ng_node", NULL, MTX_SPIN); 606 node->nd_input_queue.queue = NULL; 607 node->nd_input_queue.last = &node->nd_input_queue.queue; 608 node->nd_input_queue.q_flags = 0; 609 node->nd_input_queue.q_node = node; 610 611 /* Initialize hook list for new node */ 612 LIST_INIT(&node->nd_hooks); 613 614 /* Link us into the node linked list */ 615 mtx_lock(&ng_nodelist_mtx); 616 LIST_INSERT_HEAD(&ng_nodelist, node, nd_nodes); 617 mtx_unlock(&ng_nodelist_mtx); 618 619 620 /* get an ID and put us in the hash chain */ 621 mtx_lock(&ng_idhash_mtx); 622 for (;;) { /* wrap protection, even if silly */ 623 node_p node2 = NULL; 624 node->nd_ID = nextID++; /* 137/second for 1 year before wrap */ 625 626 /* Is there a problem with the new number? */ 627 NG_IDHASH_FIND(node->nd_ID, node2); /* already taken? */ 628 if ((node->nd_ID != 0) && (node2 == NULL)) { 629 break; 630 } 631 } 632 LIST_INSERT_HEAD(&ng_ID_hash[NG_IDHASH_FN(node->nd_ID)], 633 node, nd_idnodes); 634 mtx_unlock(&ng_idhash_mtx); 635 636 /* Done */ 637 *nodepp = node; 638 return (0); 639 } 640 641 /* 642 * Forceably start the shutdown process on a node. Either call 643 * it's shutdown method, or do the default shutdown if there is 644 * no type-specific method. 645 * 646 * We can only be called form a shutdown message, so we know we have 647 * a writer lock, and therefore exclusive access. It also means 648 * that we should not be on the work queue, but we check anyhow. 649 * 650 * Persistent node types must have a type-specific method which 651 * Allocates a new node in which case, this one is irretrievably going away, 652 * or cleans up anything it needs, and just makes the node valid again, 653 * in which case we allow the node to survive. 654 * 655 * XXX We need to think of how to tell a persistant node that we 656 * REALLY need to go away because the hardware has gone or we 657 * are rebooting.... etc. 658 */ 659 void 660 ng_rmnode(node_p node, hook_p dummy1, void *dummy2, int dummy3) 661 { 662 hook_p hook; 663 664 /* Check if it's already shutting down */ 665 if ((node->nd_flags & NGF_CLOSING) != 0) 666 return; 667 668 if (node == &ng_deadnode) { 669 printf ("shutdown called on deadnode\n"); 670 return; 671 } 672 673 /* Add an extra reference so it doesn't go away during this */ 674 NG_NODE_REF(node); 675 676 /* 677 * Mark it invalid so any newcomers know not to try use it 678 * Also add our own mark so we can't recurse 679 * note that NGF_INVALID does not do this as it's also set during 680 * creation 681 */ 682 node->nd_flags |= NGF_INVALID|NGF_CLOSING; 683 684 /* If node has its pre-shutdown method, then call it first*/ 685 if (node->nd_type && node->nd_type->close) 686 (*node->nd_type->close)(node); 687 688 /* Notify all remaining connected nodes to disconnect */ 689 while ((hook = LIST_FIRST(&node->nd_hooks)) != NULL) 690 ng_destroy_hook(hook); 691 692 /* 693 * Drain the input queue forceably. 694 * it has no hooks so what's it going to do, bleed on someone? 695 * Theoretically we came here from a queue entry that was added 696 * Just before the queue was closed, so it should be empty anyway. 697 * Also removes us from worklist if needed. 698 */ 699 ng_flush_input_queue(&node->nd_input_queue); 700 701 /* Ask the type if it has anything to do in this case */ 702 if (node->nd_type && node->nd_type->shutdown) { 703 (*node->nd_type->shutdown)(node); 704 if (NG_NODE_IS_VALID(node)) { 705 /* 706 * Well, blow me down if the node code hasn't declared 707 * that it doesn't want to die. 708 * Presumably it is a persistant node. 709 * If we REALLY want it to go away, 710 * e.g. hardware going away, 711 * Our caller should set NGF_REALLY_DIE in nd_flags. 712 */ 713 node->nd_flags &= ~(NGF_INVALID|NGF_CLOSING); 714 NG_NODE_UNREF(node); /* Assume they still have theirs */ 715 return; 716 } 717 } else { /* do the default thing */ 718 NG_NODE_UNREF(node); 719 } 720 721 ng_unname(node); /* basically a NOP these days */ 722 723 /* 724 * Remove extra reference, possibly the last 725 * Possible other holders of references may include 726 * timeout callouts, but theoretically the node's supposed to 727 * have cancelled them. Possibly hardware dependencies may 728 * force a driver to 'linger' with a reference. 729 */ 730 NG_NODE_UNREF(node); 731 } 732 733 #ifdef NETGRAPH_DEBUG 734 void 735 ng_ref_node(node_p node) 736 { 737 _NG_NODE_REF(node); 738 } 739 #endif 740 741 /* 742 * Remove a reference to the node, possibly the last. 743 * deadnode always acts as it it were the last. 744 */ 745 int 746 ng_unref_node(node_p node) 747 { 748 int v; 749 750 if (node == &ng_deadnode) { 751 return (0); 752 } 753 754 do { 755 v = node->nd_refs - 1; 756 } while (! atomic_cmpset_int(&node->nd_refs, v + 1, v)); 757 758 if (v == 0) { /* we were the last */ 759 760 mtx_lock(&ng_nodelist_mtx); 761 node->nd_type->refs--; /* XXX maybe should get types lock? */ 762 LIST_REMOVE(node, nd_nodes); 763 mtx_unlock(&ng_nodelist_mtx); 764 765 mtx_lock(&ng_idhash_mtx); 766 LIST_REMOVE(node, nd_idnodes); 767 mtx_unlock(&ng_idhash_mtx); 768 769 mtx_destroy(&node->nd_input_queue.q_mtx); 770 NG_FREE_NODE(node); 771 } 772 return (v); 773 } 774 775 /************************************************************************ 776 Node ID handling 777 ************************************************************************/ 778 static node_p 779 ng_ID2noderef(ng_ID_t ID) 780 { 781 node_p node; 782 mtx_lock(&ng_idhash_mtx); 783 NG_IDHASH_FIND(ID, node); 784 if(node) 785 NG_NODE_REF(node); 786 mtx_unlock(&ng_idhash_mtx); 787 return(node); 788 } 789 790 ng_ID_t 791 ng_node2ID(node_p node) 792 { 793 return (node ? NG_NODE_ID(node) : 0); 794 } 795 796 /************************************************************************ 797 Node name handling 798 ************************************************************************/ 799 800 /* 801 * Assign a node a name. Once assigned, the name cannot be changed. 802 */ 803 int 804 ng_name_node(node_p node, const char *name) 805 { 806 int i; 807 node_p node2; 808 809 /* Check the name is valid */ 810 for (i = 0; i < NG_NODESIZ; i++) { 811 if (name[i] == '\0' || name[i] == '.' || name[i] == ':') 812 break; 813 } 814 if (i == 0 || name[i] != '\0') { 815 TRAP_ERROR(); 816 return (EINVAL); 817 } 818 if (ng_decodeidname(name) != 0) { /* valid IDs not allowed here */ 819 TRAP_ERROR(); 820 return (EINVAL); 821 } 822 823 /* Check the name isn't already being used */ 824 if ((node2 = ng_name2noderef(node, name)) != NULL) { 825 NG_NODE_UNREF(node2); 826 TRAP_ERROR(); 827 return (EADDRINUSE); 828 } 829 830 /* copy it */ 831 strlcpy(NG_NODE_NAME(node), name, NG_NODESIZ); 832 833 return (0); 834 } 835 836 /* 837 * Find a node by absolute name. The name should NOT end with ':' 838 * The name "." means "this node" and "[xxx]" means "the node 839 * with ID (ie, at address) xxx". 840 * 841 * Returns the node if found, else NULL. 842 * Eventually should add something faster than a sequential search. 843 * Note it aquires a reference on the node so you can be sure it's still there. 844 */ 845 node_p 846 ng_name2noderef(node_p here, const char *name) 847 { 848 node_p node; 849 ng_ID_t temp; 850 851 /* "." means "this node" */ 852 if (strcmp(name, ".") == 0) { 853 NG_NODE_REF(here); 854 return(here); 855 } 856 857 /* Check for name-by-ID */ 858 if ((temp = ng_decodeidname(name)) != 0) { 859 return (ng_ID2noderef(temp)); 860 } 861 862 /* Find node by name */ 863 mtx_lock(&ng_nodelist_mtx); 864 LIST_FOREACH(node, &ng_nodelist, nd_nodes) { 865 if (NG_NODE_IS_VALID(node) 866 && NG_NODE_HAS_NAME(node) 867 && (strcmp(NG_NODE_NAME(node), name) == 0)) { 868 break; 869 } 870 } 871 if (node) 872 NG_NODE_REF(node); 873 mtx_unlock(&ng_nodelist_mtx); 874 return (node); 875 } 876 877 /* 878 * Decode an ID name, eg. "[f03034de]". Returns 0 if the 879 * string is not valid, otherwise returns the value. 880 */ 881 static ng_ID_t 882 ng_decodeidname(const char *name) 883 { 884 const int len = strlen(name); 885 char *eptr; 886 u_long val; 887 888 /* Check for proper length, brackets, no leading junk */ 889 if ((len < 3) 890 || (name[0] != '[') 891 || (name[len - 1] != ']') 892 || (!isxdigit(name[1]))) { 893 return ((ng_ID_t)0); 894 } 895 896 /* Decode number */ 897 val = strtoul(name + 1, &eptr, 16); 898 if ((eptr - name != len - 1) 899 || (val == ULONG_MAX) 900 || (val == 0)) { 901 return ((ng_ID_t)0); 902 } 903 return (ng_ID_t)val; 904 } 905 906 /* 907 * Remove a name from a node. This should only be called 908 * when shutting down and removing the node. 909 * IF we allow name changing this may be more resurected. 910 */ 911 void 912 ng_unname(node_p node) 913 { 914 } 915 916 /************************************************************************ 917 Hook routines 918 Names are not optional. Hooks are always connected, except for a 919 brief moment within these routines. On invalidation or during creation 920 they are connected to the 'dead' hook. 921 ************************************************************************/ 922 923 /* 924 * Remove a hook reference 925 */ 926 void 927 ng_unref_hook(hook_p hook) 928 { 929 int v; 930 931 if (hook == &ng_deadhook) { 932 return; 933 } 934 do { 935 v = hook->hk_refs; 936 } while (! atomic_cmpset_int(&hook->hk_refs, v, v - 1)); 937 938 if (v == 1) { /* we were the last */ 939 if (_NG_HOOK_NODE(hook)) { /* it'll probably be ng_deadnode */ 940 _NG_NODE_UNREF((_NG_HOOK_NODE(hook))); 941 hook->hk_node = NULL; 942 } 943 NG_FREE_HOOK(hook); 944 } 945 } 946 947 /* 948 * Add an unconnected hook to a node. Only used internally. 949 * Assumes node is locked. (XXX not yet true ) 950 */ 951 static int 952 ng_add_hook(node_p node, const char *name, hook_p *hookp) 953 { 954 hook_p hook; 955 int error = 0; 956 957 /* Check that the given name is good */ 958 if (name == NULL) { 959 TRAP_ERROR(); 960 return (EINVAL); 961 } 962 if (ng_findhook(node, name) != NULL) { 963 TRAP_ERROR(); 964 return (EEXIST); 965 } 966 967 /* Allocate the hook and link it up */ 968 NG_ALLOC_HOOK(hook); 969 if (hook == NULL) { 970 TRAP_ERROR(); 971 return (ENOMEM); 972 } 973 hook->hk_refs = 1; /* add a reference for us to return */ 974 hook->hk_flags = HK_INVALID; 975 hook->hk_peer = &ng_deadhook; /* start off this way */ 976 hook->hk_node = node; 977 NG_NODE_REF(node); /* each hook counts as a reference */ 978 979 /* Set hook name */ 980 strlcpy(NG_HOOK_NAME(hook), name, NG_HOOKSIZ); 981 982 /* 983 * Check if the node type code has something to say about it 984 * If it fails, the unref of the hook will also unref the node. 985 */ 986 if (node->nd_type->newhook != NULL) { 987 if ((error = (*node->nd_type->newhook)(node, hook, name))) { 988 NG_HOOK_UNREF(hook); /* this frees the hook */ 989 return (error); 990 } 991 } 992 /* 993 * The 'type' agrees so far, so go ahead and link it in. 994 * We'll ask again later when we actually connect the hooks. 995 */ 996 LIST_INSERT_HEAD(&node->nd_hooks, hook, hk_hooks); 997 node->nd_numhooks++; 998 NG_HOOK_REF(hook); /* one for the node */ 999 1000 if (hookp) 1001 *hookp = hook; 1002 return (0); 1003 } 1004 1005 /* 1006 * Find a hook 1007 * 1008 * Node types may supply their own optimized routines for finding 1009 * hooks. If none is supplied, we just do a linear search. 1010 * XXX Possibly we should add a reference to the hook? 1011 */ 1012 hook_p 1013 ng_findhook(node_p node, const char *name) 1014 { 1015 hook_p hook; 1016 1017 if (node->nd_type->findhook != NULL) 1018 return (*node->nd_type->findhook)(node, name); 1019 LIST_FOREACH(hook, &node->nd_hooks, hk_hooks) { 1020 if (NG_HOOK_IS_VALID(hook) 1021 && (strcmp(NG_HOOK_NAME(hook), name) == 0)) 1022 return (hook); 1023 } 1024 return (NULL); 1025 } 1026 1027 /* 1028 * Destroy a hook 1029 * 1030 * As hooks are always attached, this really destroys two hooks. 1031 * The one given, and the one attached to it. Disconnect the hooks 1032 * from each other first. We reconnect the peer hook to the 'dead' 1033 * hook so that it can still exist after we depart. We then 1034 * send the peer its own destroy message. This ensures that we only 1035 * interact with the peer's structures when it is locked processing that 1036 * message. We hold a reference to the peer hook so we are guaranteed that 1037 * the peer hook and node are still going to exist until 1038 * we are finished there as the hook holds a ref on the node. 1039 * We run this same code again on the peer hook, but that time it is already 1040 * attached to the 'dead' hook. 1041 * 1042 * This routine is called at all stages of hook creation 1043 * on error detection and must be able to handle any such stage. 1044 */ 1045 void 1046 ng_destroy_hook(hook_p hook) 1047 { 1048 hook_p peer = NG_HOOK_PEER(hook); 1049 node_p node = NG_HOOK_NODE(hook); 1050 1051 if (hook == &ng_deadhook) { /* better safe than sorry */ 1052 printf("ng_destroy_hook called on deadhook\n"); 1053 return; 1054 } 1055 hook->hk_flags |= HK_INVALID; /* as soon as possible */ 1056 if (peer && (peer != &ng_deadhook)) { 1057 /* 1058 * Set the peer to point to ng_deadhook 1059 * from this moment on we are effectively independent it. 1060 * send it an rmhook message of it's own. 1061 */ 1062 peer->hk_peer = &ng_deadhook; /* They no longer know us */ 1063 hook->hk_peer = &ng_deadhook; /* Nor us, them */ 1064 if (NG_HOOK_NODE(peer) == &ng_deadnode) { 1065 /* 1066 * If it's already divorced from a node, 1067 * just free it. 1068 */ 1069 /* nothing */ 1070 } else { 1071 ng_rmhook_self(peer); /* Send it a surprise */ 1072 } 1073 NG_HOOK_UNREF(peer); /* account for peer link */ 1074 NG_HOOK_UNREF(hook); /* account for peer link */ 1075 } 1076 1077 /* 1078 * Remove the hook from the node's list to avoid possible recursion 1079 * in case the disconnection results in node shutdown. 1080 */ 1081 if (node == &ng_deadnode) { /* happens if called from ng_con_nodes() */ 1082 return; 1083 } 1084 LIST_REMOVE(hook, hk_hooks); 1085 node->nd_numhooks--; 1086 if (node->nd_type->disconnect) { 1087 /* 1088 * The type handler may elect to destroy the node so don't 1089 * trust its existance after this point. (except 1090 * that we still hold a reference on it. (which we 1091 * inherrited from the hook we are destroying) 1092 */ 1093 (*node->nd_type->disconnect) (hook); 1094 } 1095 1096 /* 1097 * Note that because we will point to ng_deadnode, the original node 1098 * is not decremented automatically so we do that manually. 1099 */ 1100 _NG_HOOK_NODE(hook) = &ng_deadnode; 1101 NG_NODE_UNREF(node); /* We no longer point to it so adjust count */ 1102 NG_HOOK_UNREF(hook); /* Account for linkage (in list) to node */ 1103 } 1104 1105 /* 1106 * Take two hooks on a node and merge the connection so that the given node 1107 * is effectively bypassed. 1108 */ 1109 int 1110 ng_bypass(hook_p hook1, hook_p hook2) 1111 { 1112 if (hook1->hk_node != hook2->hk_node) { 1113 TRAP_ERROR(); 1114 return (EINVAL); 1115 } 1116 hook1->hk_peer->hk_peer = hook2->hk_peer; 1117 hook2->hk_peer->hk_peer = hook1->hk_peer; 1118 1119 hook1->hk_peer = &ng_deadhook; 1120 hook2->hk_peer = &ng_deadhook; 1121 1122 /* XXX If we ever cache methods on hooks update them as well */ 1123 ng_destroy_hook(hook1); 1124 ng_destroy_hook(hook2); 1125 return (0); 1126 } 1127 1128 /* 1129 * Install a new netgraph type 1130 */ 1131 int 1132 ng_newtype(struct ng_type *tp) 1133 { 1134 const size_t namelen = strlen(tp->name); 1135 1136 /* Check version and type name fields */ 1137 if ((tp->version != NG_ABI_VERSION) 1138 || (namelen == 0) 1139 || (namelen >= NG_TYPESIZ)) { 1140 TRAP_ERROR(); 1141 if (tp->version != NG_ABI_VERSION) { 1142 printf("Netgraph: Node type rejected. ABI mismatch. Suggest recompile\n"); 1143 } 1144 return (EINVAL); 1145 } 1146 1147 /* Check for name collision */ 1148 if (ng_findtype(tp->name) != NULL) { 1149 TRAP_ERROR(); 1150 return (EEXIST); 1151 } 1152 1153 1154 /* Link in new type */ 1155 mtx_lock(&ng_typelist_mtx); 1156 LIST_INSERT_HEAD(&ng_typelist, tp, types); 1157 tp->refs = 1; /* first ref is linked list */ 1158 mtx_unlock(&ng_typelist_mtx); 1159 return (0); 1160 } 1161 1162 /* 1163 * unlink a netgraph type 1164 * If no examples exist 1165 */ 1166 int 1167 ng_rmtype(struct ng_type *tp) 1168 { 1169 /* Check for name collision */ 1170 if (tp->refs != 1) { 1171 TRAP_ERROR(); 1172 return (EBUSY); 1173 } 1174 1175 /* Unlink type */ 1176 mtx_lock(&ng_typelist_mtx); 1177 LIST_REMOVE(tp, types); 1178 mtx_unlock(&ng_typelist_mtx); 1179 return (0); 1180 } 1181 1182 /* 1183 * Look for a type of the name given 1184 */ 1185 struct ng_type * 1186 ng_findtype(const char *typename) 1187 { 1188 struct ng_type *type; 1189 1190 mtx_lock(&ng_typelist_mtx); 1191 LIST_FOREACH(type, &ng_typelist, types) { 1192 if (strcmp(type->name, typename) == 0) 1193 break; 1194 } 1195 mtx_unlock(&ng_typelist_mtx); 1196 return (type); 1197 } 1198 1199 /************************************************************************ 1200 Composite routines 1201 ************************************************************************/ 1202 /* 1203 * Connect two nodes using the specified hooks, using queued functions. 1204 */ 1205 static void 1206 ng_con_part3(node_p node, hook_p hook, void *arg1, int arg2) 1207 { 1208 1209 /* 1210 * When we run, we know that the node 'node' is locked for us. 1211 * Our caller has a reference on the hook. 1212 * Our caller has a reference on the node. 1213 * (In this case our caller is ng_apply_item() ). 1214 * The peer hook has a reference on the hook. 1215 * We are all set up except for the final call to the node, and 1216 * the clearing of the INVALID flag. 1217 */ 1218 if (NG_HOOK_NODE(hook) == &ng_deadnode) { 1219 /* 1220 * The node must have been freed again since we last visited 1221 * here. ng_destry_hook() has this effect but nothing else does. 1222 * We should just release our references and 1223 * free anything we can think of. 1224 * Since we know it's been destroyed, and it's our caller 1225 * that holds the references, just return. 1226 */ 1227 return ; 1228 } 1229 if (hook->hk_node->nd_type->connect) { 1230 if ((*hook->hk_node->nd_type->connect) (hook)) { 1231 ng_destroy_hook(hook); /* also zaps peer */ 1232 printf("failed in ng_con_part3()\n"); 1233 return ; 1234 } 1235 } 1236 /* 1237 * XXX this is wrong for SMP. Possibly we need 1238 * to separate out 'create' and 'invalid' flags. 1239 * should only set flags on hooks we have locked under our node. 1240 */ 1241 hook->hk_flags &= ~HK_INVALID; 1242 return ; 1243 } 1244 1245 static void 1246 ng_con_part2(node_p node, hook_p hook, void *arg1, int arg2) 1247 { 1248 1249 /* 1250 * When we run, we know that the node 'node' is locked for us. 1251 * Our caller has a reference on the hook. 1252 * Our caller has a reference on the node. 1253 * (In this case our caller is ng_apply_item() ). 1254 * The peer hook has a reference on the hook. 1255 * our node pointer points to the 'dead' node. 1256 * First check the hook name is unique. 1257 * Should not happen because we checked before queueing this. 1258 */ 1259 if (ng_findhook(node, NG_HOOK_NAME(hook)) != NULL) { 1260 TRAP_ERROR(); 1261 ng_destroy_hook(hook); /* should destroy peer too */ 1262 printf("failed in ng_con_part2()\n"); 1263 return ; 1264 } 1265 /* 1266 * Check if the node type code has something to say about it 1267 * If it fails, the unref of the hook will also unref the attached node, 1268 * however since that node is 'ng_deadnode' this will do nothing. 1269 * The peer hook will also be destroyed. 1270 */ 1271 if (node->nd_type->newhook != NULL) { 1272 if ((*node->nd_type->newhook)(node, hook, hook->hk_name)) { 1273 ng_destroy_hook(hook); /* should destroy peer too */ 1274 printf("failed in ng_con_part2()\n"); 1275 return ; 1276 } 1277 } 1278 1279 /* 1280 * The 'type' agrees so far, so go ahead and link it in. 1281 * We'll ask again later when we actually connect the hooks. 1282 */ 1283 hook->hk_node = node; /* just overwrite ng_deadnode */ 1284 NG_NODE_REF(node); /* each hook counts as a reference */ 1285 LIST_INSERT_HEAD(&node->nd_hooks, hook, hk_hooks); 1286 node->nd_numhooks++; 1287 NG_HOOK_REF(hook); /* one for the node */ 1288 1289 /* 1290 * We now have a symetrical situation, where both hooks have been 1291 * linked to their nodes, the newhook methods have been called 1292 * And the references are all correct. The hooks are still marked 1293 * as invalid, as we have not called the 'connect' methods 1294 * yet. 1295 * We can call the local one immediatly as we have the 1296 * node locked, but we need to queue the remote one. 1297 */ 1298 if (hook->hk_node->nd_type->connect) { 1299 if ((*hook->hk_node->nd_type->connect) (hook)) { 1300 ng_destroy_hook(hook); /* also zaps peer */ 1301 printf("failed in ng_con_part2(A)\n"); 1302 return ; 1303 } 1304 } 1305 if (ng_send_fn(hook->hk_peer->hk_node, hook->hk_peer, 1306 &ng_con_part3, arg1, arg2)) { 1307 printf("failed in ng_con_part2(B)"); 1308 ng_destroy_hook(hook); /* also zaps peer */ 1309 return ; 1310 } 1311 hook->hk_flags &= ~HK_INVALID; /* need both to be able to work */ 1312 return ; 1313 } 1314 1315 /* 1316 * Connect this node with another node. We assume that this node is 1317 * currently locked, as we are only called from an NGM_CONNECT message. 1318 */ 1319 static int 1320 ng_con_nodes(node_p node, const char *name, node_p node2, const char *name2) 1321 { 1322 int error; 1323 hook_p hook; 1324 hook_p hook2; 1325 1326 if (ng_findhook(node2, name2) != NULL) { 1327 return(EEXIST); 1328 } 1329 if ((error = ng_add_hook(node, name, &hook))) /* gives us a ref */ 1330 return (error); 1331 /* Allocate the other hook and link it up */ 1332 NG_ALLOC_HOOK(hook2); 1333 if (hook2 == NULL) { 1334 TRAP_ERROR(); 1335 ng_destroy_hook(hook); /* XXX check ref counts so far */ 1336 NG_HOOK_UNREF(hook); /* including our ref */ 1337 return (ENOMEM); 1338 } 1339 hook2->hk_refs = 1; /* start with a reference for us. */ 1340 hook2->hk_flags = HK_INVALID; 1341 hook2->hk_peer = hook; /* Link the two together */ 1342 hook->hk_peer = hook2; 1343 NG_HOOK_REF(hook); /* Add a ref for the peer to each*/ 1344 NG_HOOK_REF(hook2); 1345 hook2->hk_node = &ng_deadnode; 1346 strlcpy(NG_HOOK_NAME(hook2), name2, NG_HOOKSIZ); 1347 1348 /* 1349 * Queue the function above. 1350 * Procesing continues in that function in the lock context of 1351 * the other node. 1352 */ 1353 ng_send_fn(node2, hook2, &ng_con_part2, NULL, 0); 1354 1355 NG_HOOK_UNREF(hook); /* Let each hook go if it wants to */ 1356 NG_HOOK_UNREF(hook2); 1357 return (0); 1358 } 1359 1360 /* 1361 * Make a peer and connect. 1362 * We assume that the local node is locked. 1363 * The new node probably doesn't need a lock until 1364 * it has a hook, because it cannot really have any work until then, 1365 * but we should think about it a bit more. 1366 * 1367 * The problem may come if the other node also fires up 1368 * some hardware or a timer or some other source of activation, 1369 * also it may already get a command msg via it's ID. 1370 * 1371 * We could use the same method as ng_con_nodes() but we'd have 1372 * to add ability to remove the node when failing. (Not hard, just 1373 * make arg1 point to the node to remove). 1374 * Unless of course we just ignore failure to connect and leave 1375 * an unconnected node? 1376 */ 1377 static int 1378 ng_mkpeer(node_p node, const char *name, const char *name2, char *type) 1379 { 1380 node_p node2; 1381 hook_p hook1; 1382 hook_p hook2; 1383 int error; 1384 1385 if ((error = ng_make_node(type, &node2))) { 1386 return (error); 1387 } 1388 1389 if ((error = ng_add_hook(node, name, &hook1))) { /* gives us a ref */ 1390 ng_rmnode(node2, NULL, NULL, 0); 1391 return (error); 1392 } 1393 1394 if ((error = ng_add_hook(node2, name2, &hook2))) { 1395 ng_rmnode(node2, NULL, NULL, 0); 1396 ng_destroy_hook(hook1); 1397 NG_HOOK_UNREF(hook1); 1398 return (error); 1399 } 1400 1401 /* 1402 * Actually link the two hooks together. 1403 */ 1404 hook1->hk_peer = hook2; 1405 hook2->hk_peer = hook1; 1406 1407 /* Each hook is referenced by the other */ 1408 NG_HOOK_REF(hook1); 1409 NG_HOOK_REF(hook2); 1410 1411 /* Give each node the opportunity to veto the pending connection */ 1412 if (hook1->hk_node->nd_type->connect) { 1413 error = (*hook1->hk_node->nd_type->connect) (hook1); 1414 } 1415 1416 if ((error == 0) && hook2->hk_node->nd_type->connect) { 1417 error = (*hook2->hk_node->nd_type->connect) (hook2); 1418 1419 } 1420 1421 /* 1422 * drop the references we were holding on the two hooks. 1423 */ 1424 if (error) { 1425 ng_destroy_hook(hook2); /* also zaps hook1 */ 1426 ng_rmnode(node2, NULL, NULL, 0); 1427 } else { 1428 /* As a last act, allow the hooks to be used */ 1429 hook1->hk_flags &= ~HK_INVALID; 1430 hook2->hk_flags &= ~HK_INVALID; 1431 } 1432 NG_HOOK_UNREF(hook1); 1433 NG_HOOK_UNREF(hook2); 1434 return (error); 1435 } 1436 1437 /************************************************************************ 1438 Utility routines to send self messages 1439 ************************************************************************/ 1440 1441 /* Shut this node down as soon as everyone is clear of it */ 1442 /* Should add arg "immediatly" to jump the queue */ 1443 int 1444 ng_rmnode_self(node_p node) 1445 { 1446 int error; 1447 1448 if (node == &ng_deadnode) 1449 return (0); 1450 node->nd_flags |= NGF_INVALID; 1451 if (node->nd_flags & NGF_CLOSING) 1452 return (0); 1453 1454 error = ng_send_fn(node, NULL, &ng_rmnode, NULL, 0); 1455 return (error); 1456 } 1457 1458 static void 1459 ng_rmhook_part2(node_p node, hook_p hook, void *arg1, int arg2) 1460 { 1461 ng_destroy_hook(hook); 1462 return ; 1463 } 1464 1465 int 1466 ng_rmhook_self(hook_p hook) 1467 { 1468 int error; 1469 node_p node = NG_HOOK_NODE(hook); 1470 1471 if (node == &ng_deadnode) 1472 return (0); 1473 1474 error = ng_send_fn(node, hook, &ng_rmhook_part2, NULL, 0); 1475 return (error); 1476 } 1477 1478 /*********************************************************************** 1479 * Parse and verify a string of the form: <NODE:><PATH> 1480 * 1481 * Such a string can refer to a specific node or a specific hook 1482 * on a specific node, depending on how you look at it. In the 1483 * latter case, the PATH component must not end in a dot. 1484 * 1485 * Both <NODE:> and <PATH> are optional. The <PATH> is a string 1486 * of hook names separated by dots. This breaks out the original 1487 * string, setting *nodep to "NODE" (or NULL if none) and *pathp 1488 * to "PATH" (or NULL if degenerate). Also, *hookp will point to 1489 * the final hook component of <PATH>, if any, otherwise NULL. 1490 * 1491 * This returns -1 if the path is malformed. The char ** are optional. 1492 ***********************************************************************/ 1493 int 1494 ng_path_parse(char *addr, char **nodep, char **pathp, char **hookp) 1495 { 1496 char *node, *path, *hook; 1497 int k; 1498 1499 /* 1500 * Extract absolute NODE, if any 1501 */ 1502 for (path = addr; *path && *path != ':'; path++); 1503 if (*path) { 1504 node = addr; /* Here's the NODE */ 1505 *path++ = '\0'; /* Here's the PATH */ 1506 1507 /* Node name must not be empty */ 1508 if (!*node) 1509 return -1; 1510 1511 /* A name of "." is OK; otherwise '.' not allowed */ 1512 if (strcmp(node, ".") != 0) { 1513 for (k = 0; node[k]; k++) 1514 if (node[k] == '.') 1515 return -1; 1516 } 1517 } else { 1518 node = NULL; /* No absolute NODE */ 1519 path = addr; /* Here's the PATH */ 1520 } 1521 1522 /* Snoop for illegal characters in PATH */ 1523 for (k = 0; path[k]; k++) 1524 if (path[k] == ':') 1525 return -1; 1526 1527 /* Check for no repeated dots in PATH */ 1528 for (k = 0; path[k]; k++) 1529 if (path[k] == '.' && path[k + 1] == '.') 1530 return -1; 1531 1532 /* Remove extra (degenerate) dots from beginning or end of PATH */ 1533 if (path[0] == '.') 1534 path++; 1535 if (*path && path[strlen(path) - 1] == '.') 1536 path[strlen(path) - 1] = 0; 1537 1538 /* If PATH has a dot, then we're not talking about a hook */ 1539 if (*path) { 1540 for (hook = path, k = 0; path[k]; k++) 1541 if (path[k] == '.') { 1542 hook = NULL; 1543 break; 1544 } 1545 } else 1546 path = hook = NULL; 1547 1548 /* Done */ 1549 if (nodep) 1550 *nodep = node; 1551 if (pathp) 1552 *pathp = path; 1553 if (hookp) 1554 *hookp = hook; 1555 return (0); 1556 } 1557 1558 /* 1559 * Given a path, which may be absolute or relative, and a starting node, 1560 * return the destination node. 1561 */ 1562 int 1563 ng_path2noderef(node_p here, const char *address, 1564 node_p *destp, hook_p *lasthook) 1565 { 1566 char fullpath[NG_PATHSIZ]; 1567 char *nodename, *path, pbuf[2]; 1568 node_p node, oldnode; 1569 char *cp; 1570 hook_p hook = NULL; 1571 1572 /* Initialize */ 1573 if (destp == NULL) { 1574 TRAP_ERROR(); 1575 return EINVAL; 1576 } 1577 *destp = NULL; 1578 1579 /* Make a writable copy of address for ng_path_parse() */ 1580 strncpy(fullpath, address, sizeof(fullpath) - 1); 1581 fullpath[sizeof(fullpath) - 1] = '\0'; 1582 1583 /* Parse out node and sequence of hooks */ 1584 if (ng_path_parse(fullpath, &nodename, &path, NULL) < 0) { 1585 TRAP_ERROR(); 1586 return EINVAL; 1587 } 1588 if (path == NULL) { 1589 pbuf[0] = '.'; /* Needs to be writable */ 1590 pbuf[1] = '\0'; 1591 path = pbuf; 1592 } 1593 1594 /* 1595 * For an absolute address, jump to the starting node. 1596 * Note that this holds a reference on the node for us. 1597 * Don't forget to drop the reference if we don't need it. 1598 */ 1599 if (nodename) { 1600 node = ng_name2noderef(here, nodename); 1601 if (node == NULL) { 1602 TRAP_ERROR(); 1603 return (ENOENT); 1604 } 1605 } else { 1606 if (here == NULL) { 1607 TRAP_ERROR(); 1608 return (EINVAL); 1609 } 1610 node = here; 1611 NG_NODE_REF(node); 1612 } 1613 1614 /* 1615 * Now follow the sequence of hooks 1616 * XXX 1617 * We actually cannot guarantee that the sequence 1618 * is not being demolished as we crawl along it 1619 * without extra-ordinary locking etc. 1620 * So this is a bit dodgy to say the least. 1621 * We can probably hold up some things by holding 1622 * the nodelist mutex for the time of this 1623 * crawl if we wanted.. At least that way we wouldn't have to 1624 * worry about the nodes dissappearing, but the hooks would still 1625 * be a problem. 1626 */ 1627 for (cp = path; node != NULL && *cp != '\0'; ) { 1628 char *segment; 1629 1630 /* 1631 * Break out the next path segment. Replace the dot we just 1632 * found with a NUL; "cp" points to the next segment (or the 1633 * NUL at the end). 1634 */ 1635 for (segment = cp; *cp != '\0'; cp++) { 1636 if (*cp == '.') { 1637 *cp++ = '\0'; 1638 break; 1639 } 1640 } 1641 1642 /* Empty segment */ 1643 if (*segment == '\0') 1644 continue; 1645 1646 /* We have a segment, so look for a hook by that name */ 1647 hook = ng_findhook(node, segment); 1648 1649 /* Can't get there from here... */ 1650 if (hook == NULL 1651 || NG_HOOK_PEER(hook) == NULL 1652 || NG_HOOK_NOT_VALID(hook) 1653 || NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook))) { 1654 TRAP_ERROR(); 1655 NG_NODE_UNREF(node); 1656 #if 0 1657 printf("hooknotvalid %s %s %d %d %d %d ", 1658 path, 1659 segment, 1660 hook == NULL, 1661 NG_HOOK_PEER(hook) == NULL, 1662 NG_HOOK_NOT_VALID(hook), 1663 NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook))); 1664 #endif 1665 return (ENOENT); 1666 } 1667 1668 /* 1669 * Hop on over to the next node 1670 * XXX 1671 * Big race conditions here as hooks and nodes go away 1672 * *** Idea.. store an ng_ID_t in each hook and use that 1673 * instead of the direct hook in this crawl? 1674 */ 1675 oldnode = node; 1676 if ((node = NG_PEER_NODE(hook))) 1677 NG_NODE_REF(node); /* XXX RACE */ 1678 NG_NODE_UNREF(oldnode); /* XXX another race */ 1679 if (NG_NODE_NOT_VALID(node)) { 1680 NG_NODE_UNREF(node); /* XXX more races */ 1681 node = NULL; 1682 } 1683 } 1684 1685 /* If node somehow missing, fail here (probably this is not needed) */ 1686 if (node == NULL) { 1687 TRAP_ERROR(); 1688 return (ENXIO); 1689 } 1690 1691 /* Done */ 1692 *destp = node; 1693 if (lasthook != NULL) 1694 *lasthook = (hook ? NG_HOOK_PEER(hook) : NULL); 1695 return (0); 1696 } 1697 1698 /***************************************************************\ 1699 * Input queue handling. 1700 * All activities are submitted to the node via the input queue 1701 * which implements a multiple-reader/single-writer gate. 1702 * Items which cannot be handled immeditly are queued. 1703 * 1704 * read-write queue locking inline functions * 1705 \***************************************************************/ 1706 1707 static __inline item_p ng_dequeue(struct ng_queue * ngq); 1708 static __inline item_p ng_acquire_read(struct ng_queue * ngq, 1709 item_p item); 1710 static __inline item_p ng_acquire_write(struct ng_queue * ngq, 1711 item_p item); 1712 static __inline void ng_leave_read(struct ng_queue * ngq); 1713 static __inline void ng_leave_write(struct ng_queue * ngq); 1714 static __inline void ng_queue_rw(struct ng_queue * ngq, 1715 item_p item, int rw); 1716 1717 /* 1718 * Definition of the bits fields in the ng_queue flag word. 1719 * Defined here rather than in netgraph.h because no-one should fiddle 1720 * with them. 1721 * 1722 * The ordering here may be important! don't shuffle these. 1723 */ 1724 /*- 1725 Safety Barrier--------+ (adjustable to suit taste) (not used yet) 1726 | 1727 V 1728 +-------+-------+-------+-------+-------+-------+-------+-------+ 1729 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 1730 | |A|c|t|i|v|e| |R|e|a|d|e|r| |C|o|u|n|t| | | | | | | | | |R|A|W| 1731 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |P|W|P| 1732 +-------+-------+-------+-------+-------+-------+-------+-------+ 1733 \___________________________ ____________________________/ | | | 1734 V | | | 1735 [active reader count] | | | 1736 | | | 1737 Read Pending ------------------------------------+ | | 1738 | | 1739 Active Writer -------------------------------------+ | 1740 | 1741 Write Pending ---------------------------------------+ 1742 1743 1744 */ 1745 #define WRITE_PENDING 0x00000001 1746 #define WRITER_ACTIVE 0x00000002 1747 #define READ_PENDING 0x00000004 1748 #define READER_INCREMENT 0x00000008 1749 #define READER_MASK 0xfffffff0 /* Not valid if WRITER_ACTIVE is set */ 1750 #define SAFETY_BARRIER 0x00100000 /* 64K items queued should be enough */ 1751 1752 /* Defines of more elaborate states on the queue */ 1753 /* Mask of bits a read cares about */ 1754 #define NGQ_RMASK (WRITE_PENDING|WRITER_ACTIVE|READ_PENDING) 1755 1756 /* Mask of bits a write cares about */ 1757 #define NGQ_WMASK (NGQ_RMASK|READER_MASK) 1758 1759 /* tests to decide if we could get a read or write off the queue */ 1760 #define CAN_GET_READ(flag) ((flag & NGQ_RMASK) == READ_PENDING) 1761 #define CAN_GET_WRITE(flag) ((flag & NGQ_WMASK) == WRITE_PENDING) 1762 1763 /* Is there a chance of getting ANY work off the queue? */ 1764 #define CAN_GET_WORK(flag) (CAN_GET_READ(flag) || CAN_GET_WRITE(flag)) 1765 1766 /* 1767 * Taking into account the current state of the queue and node, possibly take 1768 * the next entry off the queue and return it. Return NULL if there was 1769 * nothing we could return, either because there really was nothing there, or 1770 * because the node was in a state where it cannot yet process the next item 1771 * on the queue. 1772 * 1773 * This MUST MUST MUST be called with the mutex held. 1774 */ 1775 static __inline item_p 1776 ng_dequeue(struct ng_queue *ngq) 1777 { 1778 item_p item; 1779 u_int add_arg; 1780 1781 mtx_assert(&ngq->q_mtx, MA_OWNED); 1782 1783 if (CAN_GET_READ(ngq->q_flags)) { 1784 /* 1785 * Head of queue is a reader and we have no write active. 1786 * We don't care how many readers are already active. 1787 * Adjust the flags for the item we are about to dequeue. 1788 * Add the correct increment for the reader count as well. 1789 */ 1790 add_arg = (READER_INCREMENT - READ_PENDING); 1791 } else if (CAN_GET_WRITE(ngq->q_flags)) { 1792 /* 1793 * There is a pending write, no readers and no active writer. 1794 * This means we can go ahead with the pending writer. Note 1795 * the fact that we now have a writer, ready for when we take 1796 * it off the queue. 1797 * 1798 * We don't need to worry about a possible collision with the 1799 * fasttrack reader. 1800 * 1801 * The fasttrack thread may take a long time to discover that we 1802 * are running so we would have an inconsistent state in the 1803 * flags for a while. Since we ignore the reader count 1804 * entirely when the WRITER_ACTIVE flag is set, this should 1805 * not matter (in fact it is defined that way). If it tests 1806 * the flag before this operation, the WRITE_PENDING flag 1807 * will make it fail, and if it tests it later, the 1808 * WRITER_ACTIVE flag will do the same. If it is SO slow that 1809 * we have actually completed the operation, and neither flag 1810 * is set (nor the READ_PENDING) by the time that it tests 1811 * the flags, then it is actually ok for it to continue. If 1812 * it completes and we've finished and the read pending is 1813 * set it still fails. 1814 * 1815 * So we can just ignore it, as long as we can ensure that the 1816 * transition from WRITE_PENDING state to the WRITER_ACTIVE 1817 * state is atomic. 1818 * 1819 * After failing, first it will be held back by the mutex, then 1820 * when it can proceed, it will queue its request, then it 1821 * would arrive at this function. Usually it will have to 1822 * leave empty handed because the ACTIVE WRITER bit will be 1823 * set. 1824 * 1825 * Adjust the flags for the item we are about to dequeue 1826 * and for the new active writer. 1827 */ 1828 add_arg = (WRITER_ACTIVE - WRITE_PENDING); 1829 /* 1830 * We want to write "active writer, no readers " Now go make 1831 * it true. In fact there may be a number in the readers 1832 * count but we know it is not true and will be fixed soon. 1833 * We will fix the flags for the next pending entry in a 1834 * moment. 1835 */ 1836 } else { 1837 /* 1838 * We can't dequeue anything.. return and say so. Probably we 1839 * have a write pending and the readers count is non zero. If 1840 * we got here because a reader hit us just at the wrong 1841 * moment with the fasttrack code, and put us in a strange 1842 * state, then it will be through in just a moment, (as soon 1843 * as we release the mutex) and keep things moving. 1844 * Make sure we remove ourselves from the work queue. 1845 */ 1846 ng_worklist_remove(ngq->q_node); 1847 return (0); 1848 } 1849 1850 /* 1851 * Now we dequeue the request (whatever it may be) and correct the 1852 * pending flags and the next and last pointers. 1853 */ 1854 item = ngq->queue; 1855 ngq->queue = item->el_next; 1856 if (ngq->last == &(item->el_next)) { 1857 /* 1858 * that was the last entry in the queue so set the 'last 1859 * pointer up correctly and make sure the pending flags are 1860 * clear. 1861 */ 1862 ngq->last = &(ngq->queue); 1863 /* 1864 * Whatever flag was set will be cleared and 1865 * the new acive field will be set by the add as well, 1866 * so we don't need to change add_arg. 1867 * But we know we don't need to be on the work list. 1868 */ 1869 atomic_add_long(&ngq->q_flags, add_arg); 1870 ng_worklist_remove(ngq->q_node); 1871 } else { 1872 /* 1873 * Since there is something on the queue, note what it is 1874 * in the flags word. 1875 */ 1876 if ((ngq->queue->el_flags & NGQF_RW) == NGQF_READER) { 1877 add_arg += READ_PENDING; 1878 } else { 1879 add_arg += WRITE_PENDING; 1880 } 1881 atomic_add_long(&ngq->q_flags, add_arg); 1882 /* 1883 * If we see more doable work, make sure we are 1884 * on the work queue. 1885 */ 1886 if (CAN_GET_WORK(ngq->q_flags)) { 1887 ng_setisr(ngq->q_node); 1888 } 1889 } 1890 /* 1891 * We have successfully cleared the old pending flag, set the new one 1892 * if it is needed, and incremented the appropriate active field. 1893 * (all in one atomic addition.. ) 1894 */ 1895 return (item); 1896 } 1897 1898 /* 1899 * Queue a packet to be picked up by someone else. 1900 * We really don't care who, but we can't or don't want to hang around 1901 * to process it ourselves. We are probably an interrupt routine.. 1902 * 1 = writer, 0 = reader 1903 */ 1904 #define NGQRW_R 0 1905 #define NGQRW_W 1 1906 static __inline void 1907 ng_queue_rw(struct ng_queue * ngq, item_p item, int rw) 1908 { 1909 mtx_assert(&ngq->q_mtx, MA_OWNED); 1910 1911 item->el_next = NULL; /* maybe not needed */ 1912 *ngq->last = item; 1913 /* 1914 * If it was the first item in the queue then we need to 1915 * set the last pointer and the type flags. 1916 */ 1917 if (ngq->last == &(ngq->queue)) { 1918 /* 1919 * When called with constants for rw, the optimiser will 1920 * remove the unneeded branch below. 1921 */ 1922 if (rw == NGQRW_W) { 1923 atomic_add_long(&ngq->q_flags, WRITE_PENDING); 1924 } else { 1925 atomic_add_long(&ngq->q_flags, READ_PENDING); 1926 } 1927 } 1928 ngq->last = &(item->el_next); 1929 } 1930 1931 1932 /* 1933 * This function 'cheats' in that it first tries to 'grab' the use of the 1934 * node, without going through the mutex. We can do this becasue of the 1935 * semantics of the lock. The semantics include a clause that says that the 1936 * value of the readers count is invalid if the WRITER_ACTIVE flag is set. It 1937 * also says that the WRITER_ACTIVE flag cannot be set if the readers count 1938 * is not zero. Note that this talks about what is valid to SET the 1939 * WRITER_ACTIVE flag, because from the moment it is set, the value if the 1940 * reader count is immaterial, and not valid. The two 'pending' flags have a 1941 * similar effect, in that If they are orthogonal to the two active fields in 1942 * how they are set, but if either is set, the attempted 'grab' need to be 1943 * backed out because there is earlier work, and we maintain ordering in the 1944 * queue. The result of this is that the reader request can try obtain use of 1945 * the node with only a single atomic addition, and without any of the mutex 1946 * overhead. If this fails the operation degenerates to the same as for other 1947 * cases. 1948 * 1949 */ 1950 static __inline item_p 1951 ng_acquire_read(struct ng_queue *ngq, item_p item) 1952 { 1953 1954 /* ######### Hack alert ######### */ 1955 atomic_add_long(&ngq->q_flags, READER_INCREMENT); 1956 if ((ngq->q_flags & NGQ_RMASK) == 0) { 1957 /* Successfully grabbed node */ 1958 return (item); 1959 } 1960 /* undo the damage if we didn't succeed */ 1961 atomic_subtract_long(&ngq->q_flags, READER_INCREMENT); 1962 1963 /* ######### End Hack alert ######### */ 1964 mtx_lock_spin((&ngq->q_mtx)); 1965 /* 1966 * Try again. Another processor (or interrupt for that matter) may 1967 * have removed the last queued item that was stopping us from 1968 * running, between the previous test, and the moment that we took 1969 * the mutex. (Or maybe a writer completed.) 1970 */ 1971 if ((ngq->q_flags & NGQ_RMASK) == 0) { 1972 atomic_add_long(&ngq->q_flags, READER_INCREMENT); 1973 mtx_unlock_spin((&ngq->q_mtx)); 1974 return (item); 1975 } 1976 1977 /* 1978 * and queue the request for later. 1979 */ 1980 item->el_flags |= NGQF_READER; 1981 ng_queue_rw(ngq, item, NGQRW_R); 1982 1983 /* 1984 * Ok, so that's the item successfully queued for later. So now we 1985 * see if we can dequeue something to run instead. 1986 */ 1987 item = ng_dequeue(ngq); 1988 mtx_unlock_spin(&(ngq->q_mtx)); 1989 return (item); 1990 } 1991 1992 static __inline item_p 1993 ng_acquire_write(struct ng_queue *ngq, item_p item) 1994 { 1995 restart: 1996 mtx_lock_spin(&(ngq->q_mtx)); 1997 /* 1998 * If there are no readers, no writer, and no pending packets, then 1999 * we can just go ahead. In all other situations we need to queue the 2000 * request 2001 */ 2002 if ((ngq->q_flags & NGQ_WMASK) == 0) { 2003 atomic_add_long(&ngq->q_flags, WRITER_ACTIVE); 2004 mtx_unlock_spin((&ngq->q_mtx)); 2005 if (ngq->q_flags & READER_MASK) { 2006 /* Collision with fast-track reader */ 2007 atomic_subtract_long(&ngq->q_flags, WRITER_ACTIVE); 2008 goto restart; 2009 } 2010 return (item); 2011 } 2012 2013 /* 2014 * and queue the request for later. 2015 */ 2016 item->el_flags &= ~NGQF_RW; 2017 ng_queue_rw(ngq, item, NGQRW_W); 2018 2019 /* 2020 * Ok, so that's the item successfully queued for later. So now we 2021 * see if we can dequeue something to run instead. 2022 */ 2023 item = ng_dequeue(ngq); 2024 mtx_unlock_spin(&(ngq->q_mtx)); 2025 return (item); 2026 } 2027 2028 static __inline void 2029 ng_leave_read(struct ng_queue *ngq) 2030 { 2031 atomic_subtract_long(&ngq->q_flags, READER_INCREMENT); 2032 } 2033 2034 static __inline void 2035 ng_leave_write(struct ng_queue *ngq) 2036 { 2037 atomic_subtract_long(&ngq->q_flags, WRITER_ACTIVE); 2038 } 2039 2040 static void 2041 ng_flush_input_queue(struct ng_queue * ngq) 2042 { 2043 item_p item; 2044 u_int add_arg; 2045 mtx_lock_spin(&ngq->q_mtx); 2046 for (;;) { 2047 /* Now take a look at what's on the queue */ 2048 if (ngq->q_flags & READ_PENDING) { 2049 add_arg = -READ_PENDING; 2050 } else if (ngq->q_flags & WRITE_PENDING) { 2051 add_arg = -WRITE_PENDING; 2052 } else { 2053 break; 2054 } 2055 2056 item = ngq->queue; 2057 ngq->queue = item->el_next; 2058 if (ngq->last == &(item->el_next)) { 2059 ngq->last = &(ngq->queue); 2060 } else { 2061 if ((ngq->queue->el_flags & NGQF_RW) == NGQF_READER) { 2062 add_arg += READ_PENDING; 2063 } else { 2064 add_arg += WRITE_PENDING; 2065 } 2066 } 2067 atomic_add_long(&ngq->q_flags, add_arg); 2068 2069 mtx_unlock_spin(&ngq->q_mtx); 2070 NG_FREE_ITEM(item); 2071 mtx_lock_spin(&ngq->q_mtx); 2072 } 2073 /* 2074 * Take us off the work queue if we are there. 2075 * We definatly have no work to be done. 2076 */ 2077 ng_worklist_remove(ngq->q_node); 2078 mtx_unlock_spin(&ngq->q_mtx); 2079 } 2080 2081 /*********************************************************************** 2082 * Externally visible method for sending or queueing messages or data. 2083 ***********************************************************************/ 2084 2085 /* 2086 * The module code should have filled out the item correctly by this stage: 2087 * Common: 2088 * reference to destination node. 2089 * Reference to destination rcv hook if relevant. 2090 * Data: 2091 * pointer to mbuf 2092 * Control_Message: 2093 * pointer to msg. 2094 * ID of original sender node. (return address) 2095 * Function: 2096 * Function pointer 2097 * void * argument 2098 * integer argument 2099 * 2100 * The nodes have several routines and macros to help with this task: 2101 */ 2102 2103 int 2104 ng_snd_item(item_p item, int queue) 2105 { 2106 hook_p hook = NGI_HOOK(item); 2107 node_p node = NGI_NODE(item); 2108 int rw; 2109 int error = 0, ierror; 2110 item_p oitem; 2111 struct ng_queue * ngq = &node->nd_input_queue; 2112 2113 #ifdef NETGRAPH_DEBUG 2114 _ngi_check(item, __FILE__, __LINE__); 2115 #endif 2116 2117 if (item == NULL) { 2118 TRAP_ERROR(); 2119 return (EINVAL); /* failed to get queue element */ 2120 } 2121 if (node == NULL) { 2122 NG_FREE_ITEM(item); 2123 TRAP_ERROR(); 2124 return (EINVAL); /* No address */ 2125 } 2126 switch(item->el_flags & NGQF_TYPE) { 2127 case NGQF_DATA: 2128 /* 2129 * DATA MESSAGE 2130 * Delivered to a node via a non-optional hook. 2131 * Both should be present in the item even though 2132 * the node is derivable from the hook. 2133 * References are held on both by the item. 2134 */ 2135 2136 /* Protect nodes from sending NULL pointers 2137 * to each other 2138 */ 2139 if (NGI_M(item) == NULL) 2140 return (EINVAL); 2141 2142 CHECK_DATA_MBUF(NGI_M(item)); 2143 if (hook == NULL) { 2144 NG_FREE_ITEM(item); 2145 TRAP_ERROR(); 2146 return(EINVAL); 2147 } 2148 if ((NG_HOOK_NOT_VALID(hook)) 2149 || (NG_NODE_NOT_VALID(NG_HOOK_NODE(hook)))) { 2150 NG_FREE_ITEM(item); 2151 return (ENOTCONN); 2152 } 2153 if ((hook->hk_flags & HK_QUEUE)) { 2154 queue = 1; 2155 } 2156 /* By default data is a reader in the locking scheme */ 2157 item->el_flags |= NGQF_READER; 2158 rw = NGQRW_R; 2159 break; 2160 case NGQF_MESG: 2161 /* 2162 * CONTROL MESSAGE 2163 * Delivered to a node. 2164 * Hook is optional. 2165 * References are held by the item on the node and 2166 * the hook if it is present. 2167 */ 2168 if (hook && (hook->hk_flags & HK_QUEUE)) { 2169 queue = 1; 2170 } 2171 /* Data messages count as writers unles explicitly exempted */ 2172 if (NGI_MSG(item)->header.cmd & NGM_READONLY) { 2173 item->el_flags |= NGQF_READER; 2174 rw = NGQRW_R; 2175 } else { 2176 item->el_flags &= ~NGQF_RW; 2177 rw = NGQRW_W; 2178 } 2179 break; 2180 case NGQF_FN: 2181 item->el_flags &= ~NGQF_RW; 2182 rw = NGQRW_W; 2183 break; 2184 default: 2185 NG_FREE_ITEM(item); 2186 TRAP_ERROR(); 2187 return (EINVAL); 2188 } 2189 /* 2190 * If the node specifies single threading, force writer semantics 2191 * Similarly the node may say one hook always produces writers. 2192 * These are over-rides. 2193 */ 2194 if ((node->nd_flags & NGF_FORCE_WRITER) 2195 || (hook && (hook->hk_flags & HK_FORCE_WRITER))) { 2196 rw = NGQRW_W; 2197 item->el_flags &= ~NGQF_READER; 2198 } 2199 if (queue) { 2200 /* Put it on the queue for that node*/ 2201 #ifdef NETGRAPH_DEBUG 2202 _ngi_check(item, __FILE__, __LINE__); 2203 #endif 2204 mtx_lock_spin(&(ngq->q_mtx)); 2205 ng_queue_rw(ngq, item, rw); 2206 /* 2207 * If there are active elements then we can rely on 2208 * them. if not we should not rely on another packet 2209 * coming here by another path, 2210 * so it is best to put us in the netisr list. 2211 * We can take the worklist lock with the node locked 2212 * BUT NOT THE REVERSE! 2213 */ 2214 if (CAN_GET_WORK(ngq->q_flags)) { 2215 ng_setisr(node); 2216 } 2217 mtx_unlock_spin(&(ngq->q_mtx)); 2218 return (0); 2219 } 2220 /* 2221 * Take a queue item and a node and see if we can apply the item to 2222 * the node. We may end up getting a different item to apply instead. 2223 * Will allow for a piggyback reply only in the case where 2224 * there is no queueing. 2225 */ 2226 2227 oitem = item; 2228 /* 2229 * We already decided how we will be queueud or treated. 2230 * Try get the appropriate operating permission. 2231 */ 2232 if (rw == NGQRW_R) { 2233 item = ng_acquire_read(ngq, item); 2234 } else { 2235 item = ng_acquire_write(ngq, item); 2236 } 2237 2238 /* 2239 * May have come back with a different item. 2240 * or maybe none at all. The one we started with will 2241 * have been queued in thises cases. 2242 */ 2243 if (item == NULL) { 2244 return (0); 2245 } 2246 2247 #ifdef NETGRAPH_DEBUG 2248 _ngi_check(item, __FILE__, __LINE__); 2249 #endif 2250 /* 2251 * Take over the reference frm the item. 2252 * Hold it until the called function returns. 2253 */ 2254 NGI_GET_NODE(item, node); /* zaps stored node */ 2255 2256 ierror = ng_apply_item(node, item); /* drops r/w lock when done */ 2257 2258 /* only return an error if it was our initial item.. (compat hack) */ 2259 if (oitem == item) { 2260 error = ierror; 2261 } 2262 2263 /* 2264 * If the node goes away when we remove the reference, 2265 * whatever we just did caused it.. whatever we do, DO NOT 2266 * access the node again! 2267 */ 2268 if (NG_NODE_UNREF(node) == 0) { 2269 return (error); 2270 } 2271 2272 /* 2273 * Now we've handled the packet we brought, (or a friend of it) let's 2274 * look for any other packets that may have been queued up. We hold 2275 * no locks, so if someone puts something in the queue after 2276 * we check that it is empty, it is their problem 2277 * to ensure it is processed. If we have the netisr thread cme in here 2278 * while we still say we have stuff to do, we may get a boost 2279 * in SMP systems. :-) 2280 */ 2281 for (;;) { 2282 /* 2283 * dequeue acquires and adjusts the input_queue as it dequeues 2284 * packets. It acquires the rw lock as needed. 2285 */ 2286 mtx_lock_spin(&ngq->q_mtx); 2287 item = ng_dequeue(ngq); /* fixes worklist too*/ 2288 if (!item) { 2289 mtx_unlock_spin(&ngq->q_mtx); 2290 return (error); 2291 } 2292 mtx_unlock_spin(&ngq->q_mtx); 2293 2294 /* 2295 * Take over the reference frm the item. 2296 * Hold it until the called function returns. 2297 */ 2298 2299 NGI_GET_NODE(item, node); /* zaps stored node */ 2300 2301 /* 2302 * We have the appropriate lock, so run the item. 2303 * When finished it will drop the lock accordingly 2304 */ 2305 ierror = ng_apply_item(node, item); 2306 2307 /* 2308 * only return an error if it was our initial 2309 * item.. (compat hack) 2310 */ 2311 if (oitem == item) { 2312 error = ierror; 2313 } 2314 2315 /* 2316 * If the node goes away when we remove the reference, 2317 * whatever we just did caused it.. whatever we do, DO NOT 2318 * access the node again! 2319 */ 2320 if (NG_NODE_UNREF(node) == 0) { 2321 break; 2322 } 2323 } 2324 return (error); 2325 } 2326 2327 /* 2328 * We have an item that was possibly queued somewhere. 2329 * It should contain all the information needed 2330 * to run it on the appropriate node/hook. 2331 */ 2332 static int 2333 ng_apply_item(node_p node, item_p item) 2334 { 2335 hook_p hook; 2336 int was_reader = ((item->el_flags & NGQF_RW)); 2337 int error = 0; 2338 ng_rcvdata_t *rcvdata; 2339 ng_rcvmsg_t *rcvmsg; 2340 2341 NGI_GET_HOOK(item, hook); /* clears stored hook */ 2342 #ifdef NETGRAPH_DEBUG 2343 _ngi_check(item, __FILE__, __LINE__); 2344 #endif 2345 switch (item->el_flags & NGQF_TYPE) { 2346 case NGQF_DATA: 2347 /* 2348 * Check things are still ok as when we were queued. 2349 */ 2350 if ((hook == NULL) 2351 || NG_HOOK_NOT_VALID(hook) 2352 || NG_NODE_NOT_VALID(node) ) { 2353 error = EIO; 2354 NG_FREE_ITEM(item); 2355 break; 2356 } 2357 /* 2358 * If no receive method, just silently drop it. 2359 * Give preference to the hook over-ride method 2360 */ 2361 if ((!(rcvdata = hook->hk_rcvdata)) 2362 && (!(rcvdata = NG_HOOK_NODE(hook)->nd_type->rcvdata))) { 2363 error = 0; 2364 NG_FREE_ITEM(item); 2365 break; 2366 } 2367 error = (*rcvdata)(hook, item); 2368 break; 2369 case NGQF_MESG: 2370 if (hook) { 2371 if (NG_HOOK_NOT_VALID(hook)) { 2372 /* 2373 * The hook has been zapped then we can't 2374 * use it. Immediatly drop its reference. 2375 * The message may not need it. 2376 */ 2377 NG_HOOK_UNREF(hook); 2378 hook = NULL; 2379 } 2380 } 2381 /* 2382 * Similarly, if the node is a zombie there is 2383 * nothing we can do with it, drop everything. 2384 */ 2385 if (NG_NODE_NOT_VALID(node)) { 2386 TRAP_ERROR(); 2387 error = EINVAL; 2388 NG_FREE_ITEM(item); 2389 } else { 2390 /* 2391 * Call the appropriate message handler for the object. 2392 * It is up to the message handler to free the message. 2393 * If it's a generic message, handle it generically, 2394 * otherwise call the type's message handler 2395 * (if it exists) 2396 * XXX (race). Remember that a queued message may 2397 * reference a node or hook that has just been 2398 * invalidated. It will exist as the queue code 2399 * is holding a reference, but.. 2400 */ 2401 2402 struct ng_mesg *msg = NGI_MSG(item); 2403 2404 /* 2405 * check if the generic handler owns it. 2406 */ 2407 if ((msg->header.typecookie == NGM_GENERIC_COOKIE) 2408 && ((msg->header.flags & NGF_RESP) == 0)) { 2409 error = ng_generic_msg(node, item, hook); 2410 break; 2411 } 2412 /* 2413 * Now see if there is a handler (hook or node specific) 2414 * in the target node. If none, silently discard. 2415 */ 2416 if (((!hook) || (!(rcvmsg = hook->hk_rcvmsg))) 2417 && (!(rcvmsg = node->nd_type->rcvmsg))) { 2418 TRAP_ERROR(); 2419 error = 0; 2420 NG_FREE_ITEM(item); 2421 break; 2422 } 2423 error = (*rcvmsg)(node, item, hook); 2424 } 2425 break; 2426 case NGQF_FN: 2427 /* 2428 * We have to implicitly trust the hook, 2429 * as some of these are used for system purposes 2430 * where the hook is invalid. In the case of 2431 * the shutdown message we allow it to hit 2432 * even if the node is invalid. 2433 */ 2434 if ((NG_NODE_NOT_VALID(node)) 2435 && (NGI_FN(item) != &ng_rmnode)) { 2436 TRAP_ERROR(); 2437 error = EINVAL; 2438 break; 2439 } 2440 (*NGI_FN(item))(node, hook, NGI_ARG1(item), NGI_ARG2(item)); 2441 NG_FREE_ITEM(item); 2442 break; 2443 2444 } 2445 /* 2446 * We held references on some of the resources 2447 * that we took from the item. Now that we have 2448 * finished doing everything, drop those references. 2449 */ 2450 if (hook) { 2451 NG_HOOK_UNREF(hook); 2452 } 2453 2454 if (was_reader) { 2455 ng_leave_read(&node->nd_input_queue); 2456 } else { 2457 ng_leave_write(&node->nd_input_queue); 2458 } 2459 return (error); 2460 } 2461 2462 /*********************************************************************** 2463 * Implement the 'generic' control messages 2464 ***********************************************************************/ 2465 static int 2466 ng_generic_msg(node_p here, item_p item, hook_p lasthook) 2467 { 2468 int error = 0; 2469 struct ng_mesg *msg; 2470 struct ng_mesg *resp = NULL; 2471 2472 NGI_GET_MSG(item, msg); 2473 if (msg->header.typecookie != NGM_GENERIC_COOKIE) { 2474 TRAP_ERROR(); 2475 error = EINVAL; 2476 goto out; 2477 } 2478 switch (msg->header.cmd) { 2479 case NGM_SHUTDOWN: 2480 ng_rmnode(here, NULL, NULL, 0); 2481 break; 2482 case NGM_MKPEER: 2483 { 2484 struct ngm_mkpeer *const mkp = (struct ngm_mkpeer *) msg->data; 2485 2486 if (msg->header.arglen != sizeof(*mkp)) { 2487 TRAP_ERROR(); 2488 error = EINVAL; 2489 break; 2490 } 2491 mkp->type[sizeof(mkp->type) - 1] = '\0'; 2492 mkp->ourhook[sizeof(mkp->ourhook) - 1] = '\0'; 2493 mkp->peerhook[sizeof(mkp->peerhook) - 1] = '\0'; 2494 error = ng_mkpeer(here, mkp->ourhook, mkp->peerhook, mkp->type); 2495 break; 2496 } 2497 case NGM_CONNECT: 2498 { 2499 struct ngm_connect *const con = 2500 (struct ngm_connect *) msg->data; 2501 node_p node2; 2502 2503 if (msg->header.arglen != sizeof(*con)) { 2504 TRAP_ERROR(); 2505 error = EINVAL; 2506 break; 2507 } 2508 con->path[sizeof(con->path) - 1] = '\0'; 2509 con->ourhook[sizeof(con->ourhook) - 1] = '\0'; 2510 con->peerhook[sizeof(con->peerhook) - 1] = '\0'; 2511 /* Don't forget we get a reference.. */ 2512 error = ng_path2noderef(here, con->path, &node2, NULL); 2513 if (error) 2514 break; 2515 error = ng_con_nodes(here, con->ourhook, node2, con->peerhook); 2516 NG_NODE_UNREF(node2); 2517 break; 2518 } 2519 case NGM_NAME: 2520 { 2521 struct ngm_name *const nam = (struct ngm_name *) msg->data; 2522 2523 if (msg->header.arglen != sizeof(*nam)) { 2524 TRAP_ERROR(); 2525 error = EINVAL; 2526 break; 2527 } 2528 nam->name[sizeof(nam->name) - 1] = '\0'; 2529 error = ng_name_node(here, nam->name); 2530 break; 2531 } 2532 case NGM_RMHOOK: 2533 { 2534 struct ngm_rmhook *const rmh = (struct ngm_rmhook *) msg->data; 2535 hook_p hook; 2536 2537 if (msg->header.arglen != sizeof(*rmh)) { 2538 TRAP_ERROR(); 2539 error = EINVAL; 2540 break; 2541 } 2542 rmh->ourhook[sizeof(rmh->ourhook) - 1] = '\0'; 2543 if ((hook = ng_findhook(here, rmh->ourhook)) != NULL) 2544 ng_destroy_hook(hook); 2545 break; 2546 } 2547 case NGM_NODEINFO: 2548 { 2549 struct nodeinfo *ni; 2550 2551 NG_MKRESPONSE(resp, msg, sizeof(*ni), M_NOWAIT); 2552 if (resp == NULL) { 2553 error = ENOMEM; 2554 break; 2555 } 2556 2557 /* Fill in node info */ 2558 ni = (struct nodeinfo *) resp->data; 2559 if (NG_NODE_HAS_NAME(here)) 2560 strcpy(ni->name, NG_NODE_NAME(here)); 2561 strcpy(ni->type, here->nd_type->name); 2562 ni->id = ng_node2ID(here); 2563 ni->hooks = here->nd_numhooks; 2564 break; 2565 } 2566 case NGM_LISTHOOKS: 2567 { 2568 const int nhooks = here->nd_numhooks; 2569 struct hooklist *hl; 2570 struct nodeinfo *ni; 2571 hook_p hook; 2572 2573 /* Get response struct */ 2574 NG_MKRESPONSE(resp, msg, sizeof(*hl) 2575 + (nhooks * sizeof(struct linkinfo)), M_NOWAIT); 2576 if (resp == NULL) { 2577 error = ENOMEM; 2578 break; 2579 } 2580 hl = (struct hooklist *) resp->data; 2581 ni = &hl->nodeinfo; 2582 2583 /* Fill in node info */ 2584 if (NG_NODE_HAS_NAME(here)) 2585 strcpy(ni->name, NG_NODE_NAME(here)); 2586 strcpy(ni->type, here->nd_type->name); 2587 ni->id = ng_node2ID(here); 2588 2589 /* Cycle through the linked list of hooks */ 2590 ni->hooks = 0; 2591 LIST_FOREACH(hook, &here->nd_hooks, hk_hooks) { 2592 struct linkinfo *const link = &hl->link[ni->hooks]; 2593 2594 if (ni->hooks >= nhooks) { 2595 log(LOG_ERR, "%s: number of %s changed\n", 2596 __func__, "hooks"); 2597 break; 2598 } 2599 if (NG_HOOK_NOT_VALID(hook)) 2600 continue; 2601 strcpy(link->ourhook, NG_HOOK_NAME(hook)); 2602 strcpy(link->peerhook, NG_PEER_HOOK_NAME(hook)); 2603 if (NG_PEER_NODE_NAME(hook)[0] != '\0') 2604 strcpy(link->nodeinfo.name, 2605 NG_PEER_NODE_NAME(hook)); 2606 strcpy(link->nodeinfo.type, 2607 NG_PEER_NODE(hook)->nd_type->name); 2608 link->nodeinfo.id = ng_node2ID(NG_PEER_NODE(hook)); 2609 link->nodeinfo.hooks = NG_PEER_NODE(hook)->nd_numhooks; 2610 ni->hooks++; 2611 } 2612 break; 2613 } 2614 2615 case NGM_LISTNAMES: 2616 case NGM_LISTNODES: 2617 { 2618 const int unnamed = (msg->header.cmd == NGM_LISTNODES); 2619 struct namelist *nl; 2620 node_p node; 2621 int num = 0; 2622 2623 mtx_lock(&ng_nodelist_mtx); 2624 /* Count number of nodes */ 2625 LIST_FOREACH(node, &ng_nodelist, nd_nodes) { 2626 if (NG_NODE_IS_VALID(node) 2627 && (unnamed || NG_NODE_HAS_NAME(node))) { 2628 num++; 2629 } 2630 } 2631 mtx_unlock(&ng_nodelist_mtx); 2632 2633 /* Get response struct */ 2634 NG_MKRESPONSE(resp, msg, sizeof(*nl) 2635 + (num * sizeof(struct nodeinfo)), M_NOWAIT); 2636 if (resp == NULL) { 2637 error = ENOMEM; 2638 break; 2639 } 2640 nl = (struct namelist *) resp->data; 2641 2642 /* Cycle through the linked list of nodes */ 2643 nl->numnames = 0; 2644 mtx_lock(&ng_nodelist_mtx); 2645 LIST_FOREACH(node, &ng_nodelist, nd_nodes) { 2646 struct nodeinfo *const np = &nl->nodeinfo[nl->numnames]; 2647 2648 if (nl->numnames >= num) { 2649 log(LOG_ERR, "%s: number of %s changed\n", 2650 __func__, "nodes"); 2651 break; 2652 } 2653 if (NG_NODE_NOT_VALID(node)) 2654 continue; 2655 if (!unnamed && (! NG_NODE_HAS_NAME(node))) 2656 continue; 2657 if (NG_NODE_HAS_NAME(node)) 2658 strcpy(np->name, NG_NODE_NAME(node)); 2659 strcpy(np->type, node->nd_type->name); 2660 np->id = ng_node2ID(node); 2661 np->hooks = node->nd_numhooks; 2662 nl->numnames++; 2663 } 2664 mtx_unlock(&ng_nodelist_mtx); 2665 break; 2666 } 2667 2668 case NGM_LISTTYPES: 2669 { 2670 struct typelist *tl; 2671 struct ng_type *type; 2672 int num = 0; 2673 2674 mtx_lock(&ng_typelist_mtx); 2675 /* Count number of types */ 2676 LIST_FOREACH(type, &ng_typelist, types) { 2677 num++; 2678 } 2679 mtx_unlock(&ng_typelist_mtx); 2680 2681 /* Get response struct */ 2682 NG_MKRESPONSE(resp, msg, sizeof(*tl) 2683 + (num * sizeof(struct typeinfo)), M_NOWAIT); 2684 if (resp == NULL) { 2685 error = ENOMEM; 2686 break; 2687 } 2688 tl = (struct typelist *) resp->data; 2689 2690 /* Cycle through the linked list of types */ 2691 tl->numtypes = 0; 2692 mtx_lock(&ng_typelist_mtx); 2693 LIST_FOREACH(type, &ng_typelist, types) { 2694 struct typeinfo *const tp = &tl->typeinfo[tl->numtypes]; 2695 2696 if (tl->numtypes >= num) { 2697 log(LOG_ERR, "%s: number of %s changed\n", 2698 __func__, "types"); 2699 break; 2700 } 2701 strcpy(tp->type_name, type->name); 2702 tp->numnodes = type->refs - 1; /* don't count list */ 2703 tl->numtypes++; 2704 } 2705 mtx_unlock(&ng_typelist_mtx); 2706 break; 2707 } 2708 2709 case NGM_BINARY2ASCII: 2710 { 2711 int bufSize = 20 * 1024; /* XXX hard coded constant */ 2712 const struct ng_parse_type *argstype; 2713 const struct ng_cmdlist *c; 2714 struct ng_mesg *binary, *ascii; 2715 2716 /* Data area must contain a valid netgraph message */ 2717 binary = (struct ng_mesg *)msg->data; 2718 if (msg->header.arglen < sizeof(struct ng_mesg) 2719 || (msg->header.arglen - sizeof(struct ng_mesg) 2720 < binary->header.arglen)) { 2721 TRAP_ERROR(); 2722 error = EINVAL; 2723 break; 2724 } 2725 2726 /* Get a response message with lots of room */ 2727 NG_MKRESPONSE(resp, msg, sizeof(*ascii) + bufSize, M_NOWAIT); 2728 if (resp == NULL) { 2729 error = ENOMEM; 2730 break; 2731 } 2732 ascii = (struct ng_mesg *)resp->data; 2733 2734 /* Copy binary message header to response message payload */ 2735 bcopy(binary, ascii, sizeof(*binary)); 2736 2737 /* Find command by matching typecookie and command number */ 2738 for (c = here->nd_type->cmdlist; 2739 c != NULL && c->name != NULL; c++) { 2740 if (binary->header.typecookie == c->cookie 2741 && binary->header.cmd == c->cmd) 2742 break; 2743 } 2744 if (c == NULL || c->name == NULL) { 2745 for (c = ng_generic_cmds; c->name != NULL; c++) { 2746 if (binary->header.typecookie == c->cookie 2747 && binary->header.cmd == c->cmd) 2748 break; 2749 } 2750 if (c->name == NULL) { 2751 NG_FREE_MSG(resp); 2752 error = ENOSYS; 2753 break; 2754 } 2755 } 2756 2757 /* Convert command name to ASCII */ 2758 snprintf(ascii->header.cmdstr, sizeof(ascii->header.cmdstr), 2759 "%s", c->name); 2760 2761 /* Convert command arguments to ASCII */ 2762 argstype = (binary->header.flags & NGF_RESP) ? 2763 c->respType : c->mesgType; 2764 if (argstype == NULL) { 2765 *ascii->data = '\0'; 2766 } else { 2767 if ((error = ng_unparse(argstype, 2768 (u_char *)binary->data, 2769 ascii->data, bufSize)) != 0) { 2770 NG_FREE_MSG(resp); 2771 break; 2772 } 2773 } 2774 2775 /* Return the result as struct ng_mesg plus ASCII string */ 2776 bufSize = strlen(ascii->data) + 1; 2777 ascii->header.arglen = bufSize; 2778 resp->header.arglen = sizeof(*ascii) + bufSize; 2779 break; 2780 } 2781 2782 case NGM_ASCII2BINARY: 2783 { 2784 int bufSize = 2000; /* XXX hard coded constant */ 2785 const struct ng_cmdlist *c; 2786 const struct ng_parse_type *argstype; 2787 struct ng_mesg *ascii, *binary; 2788 int off = 0; 2789 2790 /* Data area must contain at least a struct ng_mesg + '\0' */ 2791 ascii = (struct ng_mesg *)msg->data; 2792 if ((msg->header.arglen < sizeof(*ascii) + 1) 2793 || (ascii->header.arglen < 1) 2794 || (msg->header.arglen 2795 < sizeof(*ascii) + ascii->header.arglen)) { 2796 TRAP_ERROR(); 2797 error = EINVAL; 2798 break; 2799 } 2800 ascii->data[ascii->header.arglen - 1] = '\0'; 2801 2802 /* Get a response message with lots of room */ 2803 NG_MKRESPONSE(resp, msg, sizeof(*binary) + bufSize, M_NOWAIT); 2804 if (resp == NULL) { 2805 error = ENOMEM; 2806 break; 2807 } 2808 binary = (struct ng_mesg *)resp->data; 2809 2810 /* Copy ASCII message header to response message payload */ 2811 bcopy(ascii, binary, sizeof(*ascii)); 2812 2813 /* Find command by matching ASCII command string */ 2814 for (c = here->nd_type->cmdlist; 2815 c != NULL && c->name != NULL; c++) { 2816 if (strcmp(ascii->header.cmdstr, c->name) == 0) 2817 break; 2818 } 2819 if (c == NULL || c->name == NULL) { 2820 for (c = ng_generic_cmds; c->name != NULL; c++) { 2821 if (strcmp(ascii->header.cmdstr, c->name) == 0) 2822 break; 2823 } 2824 if (c->name == NULL) { 2825 NG_FREE_MSG(resp); 2826 error = ENOSYS; 2827 break; 2828 } 2829 } 2830 2831 /* Convert command name to binary */ 2832 binary->header.cmd = c->cmd; 2833 binary->header.typecookie = c->cookie; 2834 2835 /* Convert command arguments to binary */ 2836 argstype = (binary->header.flags & NGF_RESP) ? 2837 c->respType : c->mesgType; 2838 if (argstype == NULL) { 2839 bufSize = 0; 2840 } else { 2841 if ((error = ng_parse(argstype, ascii->data, 2842 &off, (u_char *)binary->data, &bufSize)) != 0) { 2843 NG_FREE_MSG(resp); 2844 break; 2845 } 2846 } 2847 2848 /* Return the result */ 2849 binary->header.arglen = bufSize; 2850 resp->header.arglen = sizeof(*binary) + bufSize; 2851 break; 2852 } 2853 2854 case NGM_TEXT_CONFIG: 2855 case NGM_TEXT_STATUS: 2856 /* 2857 * This one is tricky as it passes the command down to the 2858 * actual node, even though it is a generic type command. 2859 * This means we must assume that the item/msg is already freed 2860 * when control passes back to us. 2861 */ 2862 if (here->nd_type->rcvmsg != NULL) { 2863 NGI_MSG(item) = msg; /* put it back as we found it */ 2864 return((*here->nd_type->rcvmsg)(here, item, lasthook)); 2865 } 2866 /* Fall through if rcvmsg not supported */ 2867 default: 2868 TRAP_ERROR(); 2869 error = EINVAL; 2870 } 2871 /* 2872 * Sometimes a generic message may be statically allocated 2873 * to avoid problems with allocating when in tight memeory situations. 2874 * Don't free it if it is so. 2875 * I break them appart here, because erros may cause a free if the item 2876 * in which case we'd be doing it twice. 2877 * they are kept together above, to simplify freeing. 2878 */ 2879 out: 2880 NG_RESPOND_MSG(error, here, item, resp); 2881 if (msg) 2882 NG_FREE_MSG(msg); 2883 return (error); 2884 } 2885 2886 /************************************************************************ 2887 Module routines 2888 ************************************************************************/ 2889 2890 /* 2891 * Handle the loading/unloading of a netgraph node type module 2892 */ 2893 int 2894 ng_mod_event(module_t mod, int event, void *data) 2895 { 2896 struct ng_type *const type = data; 2897 int s, error = 0; 2898 2899 switch (event) { 2900 case MOD_LOAD: 2901 2902 /* Register new netgraph node type */ 2903 s = splnet(); 2904 if ((error = ng_newtype(type)) != 0) { 2905 splx(s); 2906 break; 2907 } 2908 2909 /* Call type specific code */ 2910 if (type->mod_event != NULL) 2911 if ((error = (*type->mod_event)(mod, event, data))) { 2912 mtx_lock(&ng_typelist_mtx); 2913 type->refs--; /* undo it */ 2914 LIST_REMOVE(type, types); 2915 mtx_unlock(&ng_typelist_mtx); 2916 } 2917 splx(s); 2918 break; 2919 2920 case MOD_UNLOAD: 2921 s = splnet(); 2922 if (type->refs > 1) { /* make sure no nodes exist! */ 2923 error = EBUSY; 2924 } else { 2925 if (type->refs == 0) { 2926 /* failed load, nothing to undo */ 2927 splx(s); 2928 break; 2929 } 2930 if (type->mod_event != NULL) { /* check with type */ 2931 error = (*type->mod_event)(mod, event, data); 2932 if (error != 0) { /* type refuses.. */ 2933 splx(s); 2934 break; 2935 } 2936 } 2937 mtx_lock(&ng_typelist_mtx); 2938 LIST_REMOVE(type, types); 2939 mtx_unlock(&ng_typelist_mtx); 2940 } 2941 splx(s); 2942 break; 2943 2944 default: 2945 if (type->mod_event != NULL) 2946 error = (*type->mod_event)(mod, event, data); 2947 else 2948 error = EOPNOTSUPP; /* XXX ? */ 2949 break; 2950 } 2951 return (error); 2952 } 2953 2954 /* 2955 * Handle loading and unloading for this code. 2956 * The only thing we need to link into is the NETISR strucure. 2957 */ 2958 static int 2959 ngb_mod_event(module_t mod, int event, void *data) 2960 { 2961 int s, error = 0; 2962 2963 switch (event) { 2964 case MOD_LOAD: 2965 /* Register line discipline */ 2966 mtx_init(&ng_worklist_mtx, "ng_worklist", NULL, MTX_SPIN); 2967 mtx_init(&ng_typelist_mtx, "netgraph types mutex", NULL, 2968 MTX_DEF); 2969 mtx_init(&ng_nodelist_mtx, "netgraph nodelist mutex", NULL, 2970 MTX_DEF); 2971 mtx_init(&ng_idhash_mtx, "netgraph idhash mutex", NULL, 2972 MTX_DEF); 2973 mtx_init(&ngq_mtx, "netgraph free item list mutex", NULL, 2974 MTX_DEF); 2975 s = splimp(); 2976 netisr_register(NETISR_NETGRAPH, (netisr_t *)ngintr, NULL, 2977 NETISR_MPSAFE); 2978 splx(s); 2979 break; 2980 case MOD_UNLOAD: 2981 /* You cant unload it because an interface may be using it. */ 2982 error = EBUSY; 2983 break; 2984 default: 2985 error = EOPNOTSUPP; 2986 break; 2987 } 2988 return (error); 2989 } 2990 2991 static moduledata_t netgraph_mod = { 2992 "netgraph", 2993 ngb_mod_event, 2994 (NULL) 2995 }; 2996 DECLARE_MODULE(netgraph, netgraph_mod, SI_SUB_NETGRAPH, SI_ORDER_MIDDLE); 2997 SYSCTL_NODE(_net, OID_AUTO, graph, CTLFLAG_RW, 0, "netgraph Family"); 2998 SYSCTL_INT(_net_graph, OID_AUTO, abi_version, CTLFLAG_RD, 0, NG_ABI_VERSION,""); 2999 SYSCTL_INT(_net_graph, OID_AUTO, msg_version, CTLFLAG_RD, 0, NG_VERSION, ""); 3000 3001 /************************************************************************ 3002 Queue element get/free routines 3003 ************************************************************************/ 3004 3005 3006 static int allocated; /* number of items malloc'd */ 3007 3008 static int maxalloc = 128; /* limit the damage of a leak */ 3009 static int ngqfreemax = 64;/* cache at most this many */ 3010 3011 TUNABLE_INT("net.graph.maxalloc", &maxalloc); 3012 SYSCTL_INT(_net_graph, OID_AUTO, maxalloc, CTLFLAG_RDTUN, &maxalloc, 3013 0, "Maximum number of queue items to allocate"); 3014 3015 TUNABLE_INT("net.graph.ngqfreemax", &ngqfreemax); 3016 SYSCTL_INT(_net_graph, OID_AUTO, ngqfreemax, CTLFLAG_RDTUN, &ngqfreemax, 3017 0, "Maximum number of free queue items to cache"); 3018 3019 static const int ngqfreelow = 4; /* try malloc if free < this */ 3020 static volatile int ngqfreesize; /* number of cached entries */ 3021 static volatile item_p ngqfree; /* free ones */ 3022 3023 #ifdef NETGRAPH_DEBUG 3024 static TAILQ_HEAD(, ng_item) ng_itemlist = TAILQ_HEAD_INITIALIZER(ng_itemlist); 3025 #endif 3026 /* 3027 * Get a queue entry 3028 * This is usually called when a packet first enters netgraph. 3029 * By definition, this is usually from an interrupt, or from a user. 3030 * Users are not so important, but try be quick for the times that it's 3031 * an interrupt. 3032 * XXX If reserve is low, we should try to get 2 from malloc as this 3033 * would indicate it often fails. 3034 */ 3035 static item_p 3036 ng_getqblk(void) 3037 { 3038 item_p item = NULL; 3039 3040 /* 3041 * Try get a cached queue block, or else allocate a new one 3042 * If we are less than our reserve, try malloc. If malloc 3043 * fails, then that's what the reserve is for... 3044 * We have our little reserve 3045 * because we use M_NOWAIT for malloc. This just helps us 3046 * avoid dropping packets while not increasing the time 3047 * we take to service the interrupt (on average) (I hope). 3048 */ 3049 mtx_lock(&ngq_mtx); 3050 3051 if ((ngqfreesize < ngqfreelow) || (ngqfree == NULL)) { 3052 if (allocated < maxalloc) { /* don't leak forever */ 3053 MALLOC(item, item_p , 3054 sizeof(*item), M_NETGRAPH_ITEM, 3055 (M_NOWAIT | M_ZERO)); 3056 if (item) { 3057 #ifdef NETGRAPH_DEBUG 3058 TAILQ_INSERT_TAIL(&ng_itemlist, item, all); 3059 #endif /* NETGRAPH_DEBUG */ 3060 allocated++; 3061 } 3062 } 3063 } 3064 3065 /* 3066 * We didn't or couldn't malloc. 3067 * try get one from our cache. 3068 */ 3069 if (item == NULL && (item = ngqfree) != NULL) { 3070 ngqfree = item->el_next; 3071 ngqfreesize--; 3072 item->el_flags &= ~NGQF_FREE; 3073 } 3074 3075 mtx_unlock(&ngq_mtx); 3076 return (item); 3077 } 3078 3079 /* 3080 * Release a queue entry 3081 */ 3082 void 3083 ng_free_item(item_p item) 3084 { 3085 3086 /* 3087 * The item may hold resources on it's own. We need to free 3088 * these before we can free the item. What they are depends upon 3089 * what kind of item it is. it is important that nodes zero 3090 * out pointers to resources that they remove from the item 3091 * or we release them again here. 3092 */ 3093 if (item->el_flags & NGQF_FREE) { 3094 panic(" Freeing free queue item"); 3095 } 3096 switch (item->el_flags & NGQF_TYPE) { 3097 case NGQF_DATA: 3098 /* If we have an mbuf still attached.. */ 3099 NG_FREE_M(_NGI_M(item)); 3100 break; 3101 case NGQF_MESG: 3102 _NGI_RETADDR(item) = 0; 3103 NG_FREE_MSG(_NGI_MSG(item)); 3104 break; 3105 case NGQF_FN: 3106 /* nothing to free really, */ 3107 _NGI_FN(item) = NULL; 3108 _NGI_ARG1(item) = NULL; 3109 _NGI_ARG2(item) = 0; 3110 case NGQF_UNDEF: 3111 break; 3112 } 3113 /* If we still have a node or hook referenced... */ 3114 _NGI_CLR_NODE(item); 3115 _NGI_CLR_HOOK(item); 3116 item->el_flags |= NGQF_FREE; 3117 3118 mtx_lock(&ngq_mtx); 3119 if (ngqfreesize < ngqfreemax) { 3120 ngqfreesize++; 3121 item->el_next = ngqfree; 3122 ngqfree = item; 3123 } else { 3124 #ifdef NETGRAPH_DEBUG 3125 TAILQ_REMOVE(&ng_itemlist, item, all); 3126 #endif /* NETGRAPH_DEBUG */ 3127 NG_FREE_ITEM_REAL(item); 3128 allocated--; 3129 } 3130 mtx_unlock(&ngq_mtx); 3131 } 3132 3133 #ifdef NETGRAPH_DEBUG 3134 void 3135 dumphook (hook_p hook, char *file, int line) 3136 { 3137 printf("hook: name %s, %d refs, Last touched:\n", 3138 _NG_HOOK_NAME(hook), hook->hk_refs); 3139 printf(" Last active @ %s, line %d\n", 3140 hook->lastfile, hook->lastline); 3141 if (line) { 3142 printf(" problem discovered at file %s, line %d\n", file, line); 3143 } 3144 } 3145 3146 void 3147 dumpnode(node_p node, char *file, int line) 3148 { 3149 printf("node: ID [%x]: type '%s', %d hooks, flags 0x%x, %d refs, %s:\n", 3150 _NG_NODE_ID(node), node->nd_type->name, 3151 node->nd_numhooks, node->nd_flags, 3152 node->nd_refs, node->nd_name); 3153 printf(" Last active @ %s, line %d\n", 3154 node->lastfile, node->lastline); 3155 if (line) { 3156 printf(" problem discovered at file %s, line %d\n", file, line); 3157 } 3158 } 3159 3160 void 3161 dumpitem(item_p item, char *file, int line) 3162 { 3163 if (item->el_flags & NGQF_FREE) { 3164 printf(" Free item, freed at %s, line %d\n", 3165 item->lastfile, item->lastline); 3166 } else { 3167 printf(" ACTIVE item, last used at %s, line %d", 3168 item->lastfile, item->lastline); 3169 switch(item->el_flags & NGQF_TYPE) { 3170 case NGQF_DATA: 3171 printf(" - [data]\n"); 3172 break; 3173 case NGQF_MESG: 3174 printf(" - retaddr[%d]:\n", _NGI_RETADDR(item)); 3175 break; 3176 case NGQF_FN: 3177 printf(" - fn@%p (%p, %p, %p, %d (%x))\n", 3178 item->body.fn.fn_fn, 3179 NGI_NODE(item), 3180 NGI_HOOK(item), 3181 item->body.fn.fn_arg1, 3182 item->body.fn.fn_arg2, 3183 item->body.fn.fn_arg2); 3184 break; 3185 case NGQF_UNDEF: 3186 printf(" - UNDEFINED!\n"); 3187 } 3188 } 3189 if (line) { 3190 printf(" problem discovered at file %s, line %d\n", file, line); 3191 if (NGI_NODE(item)) { 3192 printf("node %p ([%x])\n", 3193 NGI_NODE(item), ng_node2ID(NGI_NODE(item))); 3194 } 3195 } 3196 } 3197 3198 static void 3199 ng_dumpitems(void) 3200 { 3201 item_p item; 3202 int i = 1; 3203 TAILQ_FOREACH(item, &ng_itemlist, all) { 3204 printf("[%d] ", i++); 3205 dumpitem(item, NULL, 0); 3206 } 3207 } 3208 3209 static void 3210 ng_dumpnodes(void) 3211 { 3212 node_p node; 3213 int i = 1; 3214 mtx_lock(&ng_nodelist_mtx); 3215 SLIST_FOREACH(node, &ng_allnodes, nd_all) { 3216 printf("[%d] ", i++); 3217 dumpnode(node, NULL, 0); 3218 } 3219 mtx_unlock(&ng_nodelist_mtx); 3220 } 3221 3222 static void 3223 ng_dumphooks(void) 3224 { 3225 hook_p hook; 3226 int i = 1; 3227 mtx_lock(&ng_nodelist_mtx); 3228 SLIST_FOREACH(hook, &ng_allhooks, hk_all) { 3229 printf("[%d] ", i++); 3230 dumphook(hook, NULL, 0); 3231 } 3232 mtx_unlock(&ng_nodelist_mtx); 3233 } 3234 3235 static int 3236 sysctl_debug_ng_dump_items(SYSCTL_HANDLER_ARGS) 3237 { 3238 int error; 3239 int val; 3240 int i; 3241 3242 val = allocated; 3243 i = 1; 3244 error = sysctl_handle_int(oidp, &val, sizeof(int), req); 3245 if (error != 0 || req->newptr == NULL) 3246 return (error); 3247 if (val == 42) { 3248 ng_dumpitems(); 3249 ng_dumpnodes(); 3250 ng_dumphooks(); 3251 } 3252 return (0); 3253 } 3254 3255 SYSCTL_PROC(_debug, OID_AUTO, ng_dump_items, CTLTYPE_INT | CTLFLAG_RW, 3256 0, sizeof(int), sysctl_debug_ng_dump_items, "I", "Number of allocated items"); 3257 #endif /* NETGRAPH_DEBUG */ 3258 3259 3260 /*********************************************************************** 3261 * Worklist routines 3262 **********************************************************************/ 3263 /* NETISR thread enters here */ 3264 /* 3265 * Pick a node off the list of nodes with work, 3266 * try get an item to process off it. 3267 * If there are no more, remove the node from the list. 3268 */ 3269 static void 3270 ngintr(void) 3271 { 3272 item_p item; 3273 node_p node = NULL; 3274 3275 for (;;) { 3276 mtx_lock_spin(&ng_worklist_mtx); 3277 node = TAILQ_FIRST(&ng_worklist); 3278 if (!node) { 3279 mtx_unlock_spin(&ng_worklist_mtx); 3280 break; 3281 } 3282 node->nd_flags &= ~NGF_WORKQ; 3283 TAILQ_REMOVE(&ng_worklist, node, nd_work); 3284 mtx_unlock_spin(&ng_worklist_mtx); 3285 /* 3286 * We have the node. We also take over the reference 3287 * that the list had on it. 3288 * Now process as much as you can, until it won't 3289 * let you have another item off the queue. 3290 * All this time, keep the reference 3291 * that lets us be sure that the node still exists. 3292 * Let the reference go at the last minute. 3293 * ng_dequeue will put us back on the worklist 3294 * if there is more too do. This may be of use if there 3295 * are Multiple Processors and multiple Net threads in the 3296 * future. 3297 */ 3298 for (;;) { 3299 mtx_lock_spin(&node->nd_input_queue.q_mtx); 3300 item = ng_dequeue(&node->nd_input_queue); 3301 if (item == NULL) { 3302 mtx_unlock_spin(&node->nd_input_queue.q_mtx); 3303 break; /* go look for another node */ 3304 } else { 3305 mtx_unlock_spin(&node->nd_input_queue.q_mtx); 3306 NGI_GET_NODE(item, node); /* zaps stored node */ 3307 ng_apply_item(node, item); 3308 NG_NODE_UNREF(node); 3309 } 3310 } 3311 NG_NODE_UNREF(node); 3312 } 3313 } 3314 3315 static void 3316 ng_worklist_remove(node_p node) 3317 { 3318 mtx_lock_spin(&ng_worklist_mtx); 3319 if (node->nd_flags & NGF_WORKQ) { 3320 node->nd_flags &= ~NGF_WORKQ; 3321 TAILQ_REMOVE(&ng_worklist, node, nd_work); 3322 mtx_unlock_spin(&ng_worklist_mtx); 3323 NG_NODE_UNREF(node); 3324 } else { 3325 mtx_unlock_spin(&ng_worklist_mtx); 3326 } 3327 } 3328 3329 /* 3330 * XXX 3331 * It's posible that a debugging NG_NODE_REF may need 3332 * to be outside the mutex zone 3333 */ 3334 static void 3335 ng_setisr(node_p node) 3336 { 3337 mtx_lock_spin(&ng_worklist_mtx); 3338 if ((node->nd_flags & NGF_WORKQ) == 0) { 3339 /* 3340 * If we are not already on the work queue, 3341 * then put us on. 3342 */ 3343 node->nd_flags |= NGF_WORKQ; 3344 TAILQ_INSERT_TAIL(&ng_worklist, node, nd_work); 3345 NG_NODE_REF(node); /* XXX fafe in mutex? */ 3346 } 3347 mtx_unlock_spin(&ng_worklist_mtx); 3348 schednetisr(NETISR_NETGRAPH); 3349 } 3350 3351 3352 /*********************************************************************** 3353 * Externally useable functions to set up a queue item ready for sending 3354 ***********************************************************************/ 3355 3356 #ifdef NETGRAPH_DEBUG 3357 #define ITEM_DEBUG_CHECKS \ 3358 do { \ 3359 if (NGI_NODE(item) ) { \ 3360 printf("item already has node"); \ 3361 kdb_enter("has node"); \ 3362 NGI_CLR_NODE(item); \ 3363 } \ 3364 if (NGI_HOOK(item) ) { \ 3365 printf("item already has hook"); \ 3366 kdb_enter("has hook"); \ 3367 NGI_CLR_HOOK(item); \ 3368 } \ 3369 } while (0) 3370 #else 3371 #define ITEM_DEBUG_CHECKS 3372 #endif 3373 3374 /* 3375 * Put mbuf into the item. 3376 * Hook and node references will be removed when the item is dequeued. 3377 * (or equivalent) 3378 * (XXX) Unsafe because no reference held by peer on remote node. 3379 * remote node might go away in this timescale. 3380 * We know the hooks can't go away because that would require getting 3381 * a writer item on both nodes and we must have at least a reader 3382 * here to eb able to do this. 3383 * Note that the hook loaded is the REMOTE hook. 3384 * 3385 * This is possibly in the critical path for new data. 3386 */ 3387 item_p 3388 ng_package_data(struct mbuf *m, void *dummy) 3389 { 3390 item_p item; 3391 3392 if ((item = ng_getqblk()) == NULL) { 3393 NG_FREE_M(m); 3394 return (NULL); 3395 } 3396 ITEM_DEBUG_CHECKS; 3397 item->el_flags = NGQF_DATA; 3398 item->el_next = NULL; 3399 NGI_M(item) = m; 3400 return (item); 3401 } 3402 3403 /* 3404 * Allocate a queue item and put items into it.. 3405 * Evaluate the address as this will be needed to queue it and 3406 * to work out what some of the fields should be. 3407 * Hook and node references will be removed when the item is dequeued. 3408 * (or equivalent) 3409 */ 3410 item_p 3411 ng_package_msg(struct ng_mesg *msg) 3412 { 3413 item_p item; 3414 3415 if ((item = ng_getqblk()) == NULL) { 3416 NG_FREE_MSG(msg); 3417 return (NULL); 3418 } 3419 ITEM_DEBUG_CHECKS; 3420 item->el_flags = NGQF_MESG; 3421 item->el_next = NULL; 3422 /* 3423 * Set the current lasthook into the queue item 3424 */ 3425 NGI_MSG(item) = msg; 3426 NGI_RETADDR(item) = 0; 3427 return (item); 3428 } 3429 3430 3431 3432 #define SET_RETADDR(item, here, retaddr) \ 3433 do { /* Data or fn items don't have retaddrs */ \ 3434 if ((item->el_flags & NGQF_TYPE) == NGQF_MESG) { \ 3435 if (retaddr) { \ 3436 NGI_RETADDR(item) = retaddr; \ 3437 } else { \ 3438 /* \ 3439 * The old return address should be ok. \ 3440 * If there isn't one, use the address \ 3441 * here. \ 3442 */ \ 3443 if (NGI_RETADDR(item) == 0) { \ 3444 NGI_RETADDR(item) \ 3445 = ng_node2ID(here); \ 3446 } \ 3447 } \ 3448 } \ 3449 } while (0) 3450 3451 int 3452 ng_address_hook(node_p here, item_p item, hook_p hook, ng_ID_t retaddr) 3453 { 3454 hook_p peer; 3455 node_p peernode; 3456 ITEM_DEBUG_CHECKS; 3457 /* 3458 * Quick sanity check.. 3459 * Since a hook holds a reference on it's node, once we know 3460 * that the peer is still connected (even if invalid,) we know 3461 * that the peer node is present, though maybe invalid. 3462 */ 3463 if ((hook == NULL) 3464 || NG_HOOK_NOT_VALID(hook) 3465 || (NG_HOOK_PEER(hook) == NULL) 3466 || NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook)) 3467 || NG_NODE_NOT_VALID(NG_PEER_NODE(hook))) { 3468 NG_FREE_ITEM(item); 3469 TRAP_ERROR(); 3470 return (ENETDOWN); 3471 } 3472 3473 /* 3474 * Transfer our interest to the other (peer) end. 3475 */ 3476 peer = NG_HOOK_PEER(hook); 3477 NG_HOOK_REF(peer); 3478 NGI_SET_HOOK(item, peer); 3479 peernode = NG_PEER_NODE(hook); 3480 NG_NODE_REF(peernode); 3481 NGI_SET_NODE(item, peernode); 3482 SET_RETADDR(item, here, retaddr); 3483 return (0); 3484 } 3485 3486 int 3487 ng_address_path(node_p here, item_p item, char *address, ng_ID_t retaddr) 3488 { 3489 node_p dest = NULL; 3490 hook_p hook = NULL; 3491 int error; 3492 3493 ITEM_DEBUG_CHECKS; 3494 /* 3495 * Note that ng_path2noderef increments the reference count 3496 * on the node for us if it finds one. So we don't have to. 3497 */ 3498 error = ng_path2noderef(here, address, &dest, &hook); 3499 if (error) { 3500 NG_FREE_ITEM(item); 3501 return (error); 3502 } 3503 NGI_SET_NODE(item, dest); 3504 if ( hook) { 3505 NG_HOOK_REF(hook); /* don't let it go while on the queue */ 3506 NGI_SET_HOOK(item, hook); 3507 } 3508 SET_RETADDR(item, here, retaddr); 3509 return (0); 3510 } 3511 3512 int 3513 ng_address_ID(node_p here, item_p item, ng_ID_t ID, ng_ID_t retaddr) 3514 { 3515 node_p dest; 3516 3517 ITEM_DEBUG_CHECKS; 3518 /* 3519 * Find the target node. 3520 */ 3521 dest = ng_ID2noderef(ID); /* GETS REFERENCE! */ 3522 if (dest == NULL) { 3523 NG_FREE_ITEM(item); 3524 TRAP_ERROR(); 3525 return(EINVAL); 3526 } 3527 /* Fill out the contents */ 3528 item->el_flags = NGQF_MESG; 3529 item->el_next = NULL; 3530 NGI_SET_NODE(item, dest); 3531 NGI_CLR_HOOK(item); 3532 SET_RETADDR(item, here, retaddr); 3533 return (0); 3534 } 3535 3536 /* 3537 * special case to send a message to self (e.g. destroy node) 3538 * Possibly indicate an arrival hook too. 3539 * Useful for removing that hook :-) 3540 */ 3541 item_p 3542 ng_package_msg_self(node_p here, hook_p hook, struct ng_mesg *msg) 3543 { 3544 item_p item; 3545 3546 /* 3547 * Find the target node. 3548 * If there is a HOOK argument, then use that in preference 3549 * to the address. 3550 */ 3551 if ((item = ng_getqblk()) == NULL) { 3552 NG_FREE_MSG(msg); 3553 return (NULL); 3554 } 3555 3556 /* Fill out the contents */ 3557 item->el_flags = NGQF_MESG; 3558 item->el_next = NULL; 3559 NG_NODE_REF(here); 3560 NGI_SET_NODE(item, here); 3561 if (hook) { 3562 NG_HOOK_REF(hook); 3563 NGI_SET_HOOK(item, hook); 3564 } 3565 NGI_MSG(item) = msg; 3566 NGI_RETADDR(item) = ng_node2ID(here); 3567 return (item); 3568 } 3569 3570 int 3571 ng_send_fn(node_p node, hook_p hook, ng_item_fn *fn, void * arg1, int arg2) 3572 { 3573 item_p item; 3574 3575 if ((item = ng_getqblk()) == NULL) { 3576 return (ENOMEM); 3577 } 3578 item->el_flags = NGQF_FN | NGQF_WRITER; 3579 NG_NODE_REF(node); /* and one for the item */ 3580 NGI_SET_NODE(item, node); 3581 if (hook) { 3582 NG_HOOK_REF(hook); 3583 NGI_SET_HOOK(item, hook); 3584 } 3585 NGI_FN(item) = fn; 3586 NGI_ARG1(item) = arg1; 3587 NGI_ARG2(item) = arg2; 3588 return(ng_snd_item(item, 0)); 3589 } 3590 3591 /* 3592 * Official timeout routines for Netgraph nodes. 3593 */ 3594 static void 3595 ng_callout_trampoline(void *arg) 3596 { 3597 item_p item = arg; 3598 3599 ng_snd_item(item, 0); 3600 } 3601 3602 3603 int 3604 ng_callout(struct callout *c, node_p node, hook_p hook, int ticks, 3605 ng_item_fn *fn, void * arg1, int arg2) 3606 { 3607 item_p item; 3608 3609 if ((item = ng_getqblk()) == NULL) 3610 return (ENOMEM); 3611 3612 item->el_flags = NGQF_FN | NGQF_WRITER; 3613 NG_NODE_REF(node); /* and one for the item */ 3614 NGI_SET_NODE(item, node); 3615 if (hook) { 3616 NG_HOOK_REF(hook); 3617 NGI_SET_HOOK(item, hook); 3618 } 3619 NGI_FN(item) = fn; 3620 NGI_ARG1(item) = arg1; 3621 NGI_ARG2(item) = arg2; 3622 callout_reset(c, ticks, &ng_callout_trampoline, item); 3623 return (0); 3624 } 3625 3626 /* A special modified version of untimeout() */ 3627 int 3628 ng_uncallout(struct callout *c, node_p node) 3629 { 3630 item_p item; 3631 int rval; 3632 3633 if (c == NULL) 3634 return (0); 3635 rval = callout_stop(c); 3636 item = c->c_arg; 3637 /* Do an extra check */ 3638 if ((rval > 0) && (c->c_func == &ng_callout_trampoline) && 3639 (NGI_NODE(item) == node)) { 3640 /* 3641 * We successfully removed it from the queue before it ran 3642 * So now we need to unreference everything that was 3643 * given extra references. (NG_FREE_ITEM does this). 3644 */ 3645 NG_FREE_ITEM(item); 3646 } 3647 3648 return (rval); 3649 } 3650 3651 /* 3652 * Set the address, if none given, give the node here. 3653 */ 3654 void 3655 ng_replace_retaddr(node_p here, item_p item, ng_ID_t retaddr) 3656 { 3657 if (retaddr) { 3658 NGI_RETADDR(item) = retaddr; 3659 } else { 3660 /* 3661 * The old return address should be ok. 3662 * If there isn't one, use the address here. 3663 */ 3664 NGI_RETADDR(item) = ng_node2ID(here); 3665 } 3666 } 3667 3668 #define TESTING 3669 #ifdef TESTING 3670 /* just test all the macros */ 3671 void 3672 ng_macro_test(item_p item); 3673 void 3674 ng_macro_test(item_p item) 3675 { 3676 node_p node = NULL; 3677 hook_p hook = NULL; 3678 struct mbuf *m; 3679 struct ng_mesg *msg; 3680 ng_ID_t retaddr; 3681 int error; 3682 3683 NGI_GET_M(item, m); 3684 NGI_GET_MSG(item, msg); 3685 retaddr = NGI_RETADDR(item); 3686 NG_SEND_DATA(error, hook, m, NULL); 3687 NG_SEND_DATA_ONLY(error, hook, m); 3688 NG_FWD_NEW_DATA(error, item, hook, m); 3689 NG_FWD_ITEM_HOOK(error, item, hook); 3690 NG_SEND_MSG_HOOK(error, node, msg, hook, retaddr); 3691 NG_SEND_MSG_ID(error, node, msg, retaddr, retaddr); 3692 NG_SEND_MSG_PATH(error, node, msg, ".:", retaddr); 3693 NG_FWD_MSG_HOOK(error, node, item, hook, retaddr); 3694 } 3695 #endif /* TESTING */ 3696 3697