1 /* 2 * ng_base.c 3 * 4 * Copyright (c) 1996-1999 Whistle Communications, Inc. 5 * All rights reserved. 6 * 7 * Subject to the following obligations and disclaimer of warranty, use and 8 * redistribution of this software, in source or object code forms, with or 9 * without modifications are expressly permitted by Whistle Communications; 10 * provided, however, that: 11 * 1. Any and all reproductions of the source or object code must include the 12 * copyright notice above and the following disclaimer of warranties; and 13 * 2. No rights are granted, in any manner or form, to use Whistle 14 * Communications, Inc. trademarks, including the mark "WHISTLE 15 * COMMUNICATIONS" on advertising, endorsements, or otherwise except as 16 * such appears in the above copyright notice or in the software. 17 * 18 * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND 19 * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO 20 * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE, 21 * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF 22 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT. 23 * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY 24 * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS 25 * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE. 26 * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES 27 * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING 28 * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, 29 * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR 30 * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY 31 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 32 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 33 * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY 34 * OF SUCH DAMAGE. 35 * 36 * Authors: Julian Elischer <julian@freebsd.org> 37 * Archie Cobbs <archie@freebsd.org> 38 * 39 * $FreeBSD$ 40 * $Whistle: ng_base.c,v 1.39 1999/01/28 23:54:53 julian Exp $ 41 */ 42 43 /* 44 * This file implements the base netgraph code. 45 */ 46 47 #include <sys/param.h> 48 #include <sys/systm.h> 49 #include <sys/errno.h> 50 #include <sys/kdb.h> 51 #include <sys/kernel.h> 52 #include <sys/limits.h> 53 #include <sys/malloc.h> 54 #include <sys/syslog.h> 55 #include <sys/sysctl.h> 56 #include <sys/queue.h> 57 #include <sys/mbuf.h> 58 #include <sys/ctype.h> 59 #include <sys/sysctl.h> 60 61 #include <net/netisr.h> 62 63 #include <netgraph/ng_message.h> 64 #include <netgraph/netgraph.h> 65 #include <netgraph/ng_parse.h> 66 67 MODULE_VERSION(netgraph, NG_ABI_VERSION); 68 69 /* List of all active nodes */ 70 static LIST_HEAD(, ng_node) ng_nodelist; 71 static struct mtx ng_nodelist_mtx; 72 73 /* Mutex that protects the free queue item list */ 74 static struct mtx ngq_mtx; 75 76 #ifdef NETGRAPH_DEBUG 77 78 static SLIST_HEAD(, ng_node) ng_allnodes; 79 static LIST_HEAD(, ng_node) ng_freenodes; /* in debug, we never free() them */ 80 static SLIST_HEAD(, ng_hook) ng_allhooks; 81 static LIST_HEAD(, ng_hook) ng_freehooks; /* in debug, we never free() them */ 82 83 static void ng_dumpitems(void); 84 static void ng_dumpnodes(void); 85 static void ng_dumphooks(void); 86 87 #endif /* NETGRAPH_DEBUG */ 88 /* 89 * DEAD versions of the structures. 90 * In order to avoid races, it is sometimes neccesary to point 91 * at SOMETHING even though theoretically, the current entity is 92 * INVALID. Use these to avoid these races. 93 */ 94 struct ng_type ng_deadtype = { 95 NG_ABI_VERSION, 96 "dead", 97 NULL, /* modevent */ 98 NULL, /* constructor */ 99 NULL, /* rcvmsg */ 100 NULL, /* shutdown */ 101 NULL, /* newhook */ 102 NULL, /* findhook */ 103 NULL, /* connect */ 104 NULL, /* rcvdata */ 105 NULL, /* disconnect */ 106 NULL, /* cmdlist */ 107 }; 108 109 struct ng_node ng_deadnode = { 110 "dead", 111 &ng_deadtype, 112 NGF_INVALID, 113 1, /* refs */ 114 0, /* numhooks */ 115 NULL, /* private */ 116 0, /* ID */ 117 LIST_HEAD_INITIALIZER(ng_deadnode.hooks), 118 {}, /* all_nodes list entry */ 119 {}, /* id hashtable list entry */ 120 {}, /* workqueue entry */ 121 { 0, 122 {}, /* should never use! (should hang) */ 123 NULL, 124 &ng_deadnode.nd_input_queue.queue, 125 &ng_deadnode 126 }, 127 #ifdef NETGRAPH_DEBUG 128 ND_MAGIC, 129 __FILE__, 130 __LINE__, 131 {NULL} 132 #endif /* NETGRAPH_DEBUG */ 133 }; 134 135 struct ng_hook ng_deadhook = { 136 "dead", 137 NULL, /* private */ 138 HK_INVALID | HK_DEAD, 139 1, /* refs always >= 1 */ 140 &ng_deadhook, /* Peer is self */ 141 &ng_deadnode, /* attached to deadnode */ 142 {}, /* hooks list */ 143 NULL, /* override rcvmsg() */ 144 NULL, /* override rcvdata() */ 145 #ifdef NETGRAPH_DEBUG 146 HK_MAGIC, 147 __FILE__, 148 __LINE__, 149 {NULL} 150 #endif /* NETGRAPH_DEBUG */ 151 }; 152 153 /* 154 * END DEAD STRUCTURES 155 */ 156 /* List nodes with unallocated work */ 157 static TAILQ_HEAD(, ng_node) ng_worklist = TAILQ_HEAD_INITIALIZER(ng_worklist); 158 static struct mtx ng_worklist_mtx; /* MUST LOCK NODE FIRST */ 159 160 /* List of installed types */ 161 static LIST_HEAD(, ng_type) ng_typelist; 162 static struct mtx ng_typelist_mtx; 163 164 /* Hash related definitions */ 165 /* XXX Don't need to initialise them because it's a LIST */ 166 #define NG_ID_HASH_SIZE 32 /* most systems wont need even this many */ 167 static LIST_HEAD(, ng_node) ng_ID_hash[NG_ID_HASH_SIZE]; 168 static struct mtx ng_idhash_mtx; 169 /* Method to find a node.. used twice so do it here */ 170 #define NG_IDHASH_FN(ID) ((ID) % (NG_ID_HASH_SIZE)) 171 #define NG_IDHASH_FIND(ID, node) \ 172 do { \ 173 mtx_assert(&ng_idhash_mtx, MA_OWNED); \ 174 LIST_FOREACH(node, &ng_ID_hash[NG_IDHASH_FN(ID)], \ 175 nd_idnodes) { \ 176 if (NG_NODE_IS_VALID(node) \ 177 && (NG_NODE_ID(node) == ID)) { \ 178 break; \ 179 } \ 180 } \ 181 } while (0) 182 183 184 /* Internal functions */ 185 static int ng_add_hook(node_p node, const char *name, hook_p * hookp); 186 static int ng_generic_msg(node_p here, item_p item, hook_p lasthook); 187 static ng_ID_t ng_decodeidname(const char *name); 188 static int ngb_mod_event(module_t mod, int event, void *data); 189 static void ng_worklist_remove(node_p node); 190 static void ngintr(void); 191 static int ng_apply_item(node_p node, item_p item); 192 static void ng_flush_input_queue(struct ng_queue * ngq); 193 static void ng_setisr(node_p node); 194 static node_p ng_ID2noderef(ng_ID_t ID); 195 static int ng_con_nodes(node_p node, const char *name, node_p node2, 196 const char *name2); 197 static void ng_con_part2(node_p node, hook_p hook, void *arg1, int arg2); 198 static void ng_con_part3(node_p node, hook_p hook, void *arg1, int arg2); 199 static int ng_mkpeer(node_p node, const char *name, 200 const char *name2, char *type); 201 202 /* imported , these used to be externally visible, some may go back */ 203 void ng_destroy_hook(hook_p hook); 204 node_p ng_name2noderef(node_p node, const char *name); 205 int ng_path2noderef(node_p here, const char *path, 206 node_p *dest, hook_p *lasthook); 207 int ng_make_node(const char *type, node_p *nodepp); 208 int ng_path_parse(char *addr, char **node, char **path, char **hook); 209 void ng_rmnode(node_p node, hook_p dummy1, void *dummy2, int dummy3); 210 void ng_unname(node_p node); 211 212 213 /* Our own netgraph malloc type */ 214 MALLOC_DEFINE(M_NETGRAPH, "netgraph", "netgraph structures and ctrl messages"); 215 MALLOC_DEFINE(M_NETGRAPH_HOOK, "netgraph_hook", "netgraph hook structures"); 216 MALLOC_DEFINE(M_NETGRAPH_NODE, "netgraph_node", "netgraph node structures"); 217 MALLOC_DEFINE(M_NETGRAPH_ITEM, "netgraph_item", "netgraph item structures"); 218 MALLOC_DEFINE(M_NETGRAPH_MSG, "netgraph_msg", "netgraph name storage"); 219 220 /* Should not be visible outside this file */ 221 222 #define _NG_ALLOC_HOOK(hook) \ 223 MALLOC(hook, hook_p, sizeof(*hook), M_NETGRAPH_HOOK, M_NOWAIT | M_ZERO) 224 #define _NG_ALLOC_NODE(node) \ 225 MALLOC(node, node_p, sizeof(*node), M_NETGRAPH_NODE, M_NOWAIT | M_ZERO) 226 227 #ifdef NETGRAPH_DEBUG /*----------------------------------------------*/ 228 /* 229 * In debug mode: 230 * In an attempt to help track reference count screwups 231 * we do not free objects back to the malloc system, but keep them 232 * in a local cache where we can examine them and keep information safely 233 * after they have been freed. 234 * We use this scheme for nodes and hooks, and to some extent for items. 235 */ 236 static __inline hook_p 237 ng_alloc_hook(void) 238 { 239 hook_p hook; 240 SLIST_ENTRY(ng_hook) temp; 241 mtx_lock(&ng_nodelist_mtx); 242 hook = LIST_FIRST(&ng_freehooks); 243 if (hook) { 244 LIST_REMOVE(hook, hk_hooks); 245 bcopy(&hook->hk_all, &temp, sizeof(temp)); 246 bzero(hook, sizeof(struct ng_hook)); 247 bcopy(&temp, &hook->hk_all, sizeof(temp)); 248 mtx_unlock(&ng_nodelist_mtx); 249 hook->hk_magic = HK_MAGIC; 250 } else { 251 mtx_unlock(&ng_nodelist_mtx); 252 _NG_ALLOC_HOOK(hook); 253 if (hook) { 254 hook->hk_magic = HK_MAGIC; 255 mtx_lock(&ng_nodelist_mtx); 256 SLIST_INSERT_HEAD(&ng_allhooks, hook, hk_all); 257 mtx_unlock(&ng_nodelist_mtx); 258 } 259 } 260 return (hook); 261 } 262 263 static __inline node_p 264 ng_alloc_node(void) 265 { 266 node_p node; 267 SLIST_ENTRY(ng_node) temp; 268 mtx_lock(&ng_nodelist_mtx); 269 node = LIST_FIRST(&ng_freenodes); 270 if (node) { 271 LIST_REMOVE(node, nd_nodes); 272 bcopy(&node->nd_all, &temp, sizeof(temp)); 273 bzero(node, sizeof(struct ng_node)); 274 bcopy(&temp, &node->nd_all, sizeof(temp)); 275 mtx_unlock(&ng_nodelist_mtx); 276 node->nd_magic = ND_MAGIC; 277 } else { 278 mtx_unlock(&ng_nodelist_mtx); 279 _NG_ALLOC_NODE(node); 280 if (node) { 281 node->nd_magic = ND_MAGIC; 282 mtx_lock(&ng_nodelist_mtx); 283 SLIST_INSERT_HEAD(&ng_allnodes, node, nd_all); 284 mtx_unlock(&ng_nodelist_mtx); 285 } 286 } 287 return (node); 288 } 289 290 #define NG_ALLOC_HOOK(hook) do { (hook) = ng_alloc_hook(); } while (0) 291 #define NG_ALLOC_NODE(node) do { (node) = ng_alloc_node(); } while (0) 292 293 294 #define NG_FREE_HOOK(hook) \ 295 do { \ 296 mtx_lock(&ng_nodelist_mtx); \ 297 LIST_INSERT_HEAD(&ng_freehooks, hook, hk_hooks); \ 298 hook->hk_magic = 0; \ 299 mtx_unlock(&ng_nodelist_mtx); \ 300 } while (0) 301 302 #define NG_FREE_NODE(node) \ 303 do { \ 304 mtx_lock(&ng_nodelist_mtx); \ 305 LIST_INSERT_HEAD(&ng_freenodes, node, nd_nodes); \ 306 node->nd_magic = 0; \ 307 mtx_unlock(&ng_nodelist_mtx); \ 308 } while (0) 309 310 #else /* NETGRAPH_DEBUG */ /*----------------------------------------------*/ 311 312 #define NG_ALLOC_HOOK(hook) _NG_ALLOC_HOOK(hook) 313 #define NG_ALLOC_NODE(node) _NG_ALLOC_NODE(node) 314 315 #define NG_FREE_HOOK(hook) do { FREE((hook), M_NETGRAPH_HOOK); } while (0) 316 #define NG_FREE_NODE(node) do { FREE((node), M_NETGRAPH_NODE); } while (0) 317 318 #endif /* NETGRAPH_DEBUG */ /*----------------------------------------------*/ 319 320 /* Warning: Generally use NG_FREE_ITEM() instead */ 321 #define NG_FREE_ITEM_REAL(item) do { FREE((item), M_NETGRAPH_ITEM); } while (0) 322 323 324 /* Set this to kdb_enter("X") to catch all errors as they occur */ 325 #ifndef TRAP_ERROR 326 #define TRAP_ERROR() 327 #endif 328 329 static ng_ID_t nextID = 1; 330 331 #ifdef INVARIANTS 332 #define CHECK_DATA_MBUF(m) do { \ 333 struct mbuf *n; \ 334 int total; \ 335 \ 336 M_ASSERTPKTHDR(m); \ 337 for (total = 0, n = (m); n != NULL; n = n->m_next) \ 338 total += n->m_len; \ 339 if ((m)->m_pkthdr.len != total) { \ 340 panic("%s: %d != %d", \ 341 __func__, (m)->m_pkthdr.len, total); \ 342 } \ 343 } while (0) 344 #else 345 #define CHECK_DATA_MBUF(m) 346 #endif 347 348 349 /************************************************************************ 350 Parse type definitions for generic messages 351 ************************************************************************/ 352 353 /* Handy structure parse type defining macro */ 354 #define DEFINE_PARSE_STRUCT_TYPE(lo, up, args) \ 355 static const struct ng_parse_struct_field \ 356 ng_ ## lo ## _type_fields[] = NG_GENERIC_ ## up ## _INFO args; \ 357 static const struct ng_parse_type ng_generic_ ## lo ## _type = { \ 358 &ng_parse_struct_type, \ 359 &ng_ ## lo ## _type_fields \ 360 } 361 362 DEFINE_PARSE_STRUCT_TYPE(mkpeer, MKPEER, ()); 363 DEFINE_PARSE_STRUCT_TYPE(connect, CONNECT, ()); 364 DEFINE_PARSE_STRUCT_TYPE(name, NAME, ()); 365 DEFINE_PARSE_STRUCT_TYPE(rmhook, RMHOOK, ()); 366 DEFINE_PARSE_STRUCT_TYPE(nodeinfo, NODEINFO, ()); 367 DEFINE_PARSE_STRUCT_TYPE(typeinfo, TYPEINFO, ()); 368 DEFINE_PARSE_STRUCT_TYPE(linkinfo, LINKINFO, (&ng_generic_nodeinfo_type)); 369 370 /* Get length of an array when the length is stored as a 32 bit 371 value immediately preceding the array -- as with struct namelist 372 and struct typelist. */ 373 static int 374 ng_generic_list_getLength(const struct ng_parse_type *type, 375 const u_char *start, const u_char *buf) 376 { 377 return *((const u_int32_t *)(buf - 4)); 378 } 379 380 /* Get length of the array of struct linkinfo inside a struct hooklist */ 381 static int 382 ng_generic_linkinfo_getLength(const struct ng_parse_type *type, 383 const u_char *start, const u_char *buf) 384 { 385 const struct hooklist *hl = (const struct hooklist *)start; 386 387 return hl->nodeinfo.hooks; 388 } 389 390 /* Array type for a variable length array of struct namelist */ 391 static const struct ng_parse_array_info ng_nodeinfoarray_type_info = { 392 &ng_generic_nodeinfo_type, 393 &ng_generic_list_getLength 394 }; 395 static const struct ng_parse_type ng_generic_nodeinfoarray_type = { 396 &ng_parse_array_type, 397 &ng_nodeinfoarray_type_info 398 }; 399 400 /* Array type for a variable length array of struct typelist */ 401 static const struct ng_parse_array_info ng_typeinfoarray_type_info = { 402 &ng_generic_typeinfo_type, 403 &ng_generic_list_getLength 404 }; 405 static const struct ng_parse_type ng_generic_typeinfoarray_type = { 406 &ng_parse_array_type, 407 &ng_typeinfoarray_type_info 408 }; 409 410 /* Array type for array of struct linkinfo in struct hooklist */ 411 static const struct ng_parse_array_info ng_generic_linkinfo_array_type_info = { 412 &ng_generic_linkinfo_type, 413 &ng_generic_linkinfo_getLength 414 }; 415 static const struct ng_parse_type ng_generic_linkinfo_array_type = { 416 &ng_parse_array_type, 417 &ng_generic_linkinfo_array_type_info 418 }; 419 420 DEFINE_PARSE_STRUCT_TYPE(typelist, TYPELIST, (&ng_generic_nodeinfoarray_type)); 421 DEFINE_PARSE_STRUCT_TYPE(hooklist, HOOKLIST, 422 (&ng_generic_nodeinfo_type, &ng_generic_linkinfo_array_type)); 423 DEFINE_PARSE_STRUCT_TYPE(listnodes, LISTNODES, 424 (&ng_generic_nodeinfoarray_type)); 425 426 /* List of commands and how to convert arguments to/from ASCII */ 427 static const struct ng_cmdlist ng_generic_cmds[] = { 428 { 429 NGM_GENERIC_COOKIE, 430 NGM_SHUTDOWN, 431 "shutdown", 432 NULL, 433 NULL 434 }, 435 { 436 NGM_GENERIC_COOKIE, 437 NGM_MKPEER, 438 "mkpeer", 439 &ng_generic_mkpeer_type, 440 NULL 441 }, 442 { 443 NGM_GENERIC_COOKIE, 444 NGM_CONNECT, 445 "connect", 446 &ng_generic_connect_type, 447 NULL 448 }, 449 { 450 NGM_GENERIC_COOKIE, 451 NGM_NAME, 452 "name", 453 &ng_generic_name_type, 454 NULL 455 }, 456 { 457 NGM_GENERIC_COOKIE, 458 NGM_RMHOOK, 459 "rmhook", 460 &ng_generic_rmhook_type, 461 NULL 462 }, 463 { 464 NGM_GENERIC_COOKIE, 465 NGM_NODEINFO, 466 "nodeinfo", 467 NULL, 468 &ng_generic_nodeinfo_type 469 }, 470 { 471 NGM_GENERIC_COOKIE, 472 NGM_LISTHOOKS, 473 "listhooks", 474 NULL, 475 &ng_generic_hooklist_type 476 }, 477 { 478 NGM_GENERIC_COOKIE, 479 NGM_LISTNAMES, 480 "listnames", 481 NULL, 482 &ng_generic_listnodes_type /* same as NGM_LISTNODES */ 483 }, 484 { 485 NGM_GENERIC_COOKIE, 486 NGM_LISTNODES, 487 "listnodes", 488 NULL, 489 &ng_generic_listnodes_type 490 }, 491 { 492 NGM_GENERIC_COOKIE, 493 NGM_LISTTYPES, 494 "listtypes", 495 NULL, 496 &ng_generic_typeinfo_type 497 }, 498 { 499 NGM_GENERIC_COOKIE, 500 NGM_TEXT_CONFIG, 501 "textconfig", 502 NULL, 503 &ng_parse_string_type 504 }, 505 { 506 NGM_GENERIC_COOKIE, 507 NGM_TEXT_STATUS, 508 "textstatus", 509 NULL, 510 &ng_parse_string_type 511 }, 512 { 513 NGM_GENERIC_COOKIE, 514 NGM_ASCII2BINARY, 515 "ascii2binary", 516 &ng_parse_ng_mesg_type, 517 &ng_parse_ng_mesg_type 518 }, 519 { 520 NGM_GENERIC_COOKIE, 521 NGM_BINARY2ASCII, 522 "binary2ascii", 523 &ng_parse_ng_mesg_type, 524 &ng_parse_ng_mesg_type 525 }, 526 { 0 } 527 }; 528 529 /************************************************************************ 530 Node routines 531 ************************************************************************/ 532 533 /* 534 * Instantiate a node of the requested type 535 */ 536 int 537 ng_make_node(const char *typename, node_p *nodepp) 538 { 539 struct ng_type *type; 540 int error; 541 542 /* Check that the type makes sense */ 543 if (typename == NULL) { 544 TRAP_ERROR(); 545 return (EINVAL); 546 } 547 548 /* Locate the node type. If we fail we return. Do not try to load 549 * module. 550 */ 551 if ((type = ng_findtype(typename)) == NULL) 552 return (ENXIO); 553 554 /* 555 * If we have a constructor, then make the node and 556 * call the constructor to do type specific initialisation. 557 */ 558 if (type->constructor != NULL) { 559 if ((error = ng_make_node_common(type, nodepp)) == 0) { 560 if ((error = ((*type->constructor)(*nodepp)) != 0)) { 561 NG_NODE_UNREF(*nodepp); 562 } 563 } 564 } else { 565 /* 566 * Node has no constructor. We cannot ask for one 567 * to be made. It must be brought into existance by 568 * some external agency. The external agency should 569 * call ng_make_node_common() directly to get the 570 * netgraph part initialised. 571 */ 572 TRAP_ERROR(); 573 error = EINVAL; 574 } 575 return (error); 576 } 577 578 /* 579 * Generic node creation. Called by node initialisation for externally 580 * instantiated nodes (e.g. hardware, sockets, etc ). 581 * The returned node has a reference count of 1. 582 */ 583 int 584 ng_make_node_common(struct ng_type *type, node_p *nodepp) 585 { 586 node_p node; 587 588 /* Require the node type to have been already installed */ 589 if (ng_findtype(type->name) == NULL) { 590 TRAP_ERROR(); 591 return (EINVAL); 592 } 593 594 /* Make a node and try attach it to the type */ 595 NG_ALLOC_NODE(node); 596 if (node == NULL) { 597 TRAP_ERROR(); 598 return (ENOMEM); 599 } 600 node->nd_type = type; 601 NG_NODE_REF(node); /* note reference */ 602 type->refs++; 603 604 mtx_init(&node->nd_input_queue.q_mtx, "ng_node", NULL, MTX_SPIN); 605 node->nd_input_queue.queue = NULL; 606 node->nd_input_queue.last = &node->nd_input_queue.queue; 607 node->nd_input_queue.q_flags = 0; 608 node->nd_input_queue.q_node = node; 609 610 /* Initialize hook list for new node */ 611 LIST_INIT(&node->nd_hooks); 612 613 /* Link us into the node linked list */ 614 mtx_lock(&ng_nodelist_mtx); 615 LIST_INSERT_HEAD(&ng_nodelist, node, nd_nodes); 616 mtx_unlock(&ng_nodelist_mtx); 617 618 619 /* get an ID and put us in the hash chain */ 620 mtx_lock(&ng_idhash_mtx); 621 for (;;) { /* wrap protection, even if silly */ 622 node_p node2 = NULL; 623 node->nd_ID = nextID++; /* 137/second for 1 year before wrap */ 624 625 /* Is there a problem with the new number? */ 626 NG_IDHASH_FIND(node->nd_ID, node2); /* already taken? */ 627 if ((node->nd_ID != 0) && (node2 == NULL)) { 628 break; 629 } 630 } 631 LIST_INSERT_HEAD(&ng_ID_hash[NG_IDHASH_FN(node->nd_ID)], 632 node, nd_idnodes); 633 mtx_unlock(&ng_idhash_mtx); 634 635 /* Done */ 636 *nodepp = node; 637 return (0); 638 } 639 640 /* 641 * Forceably start the shutdown process on a node. Either call 642 * it's shutdown method, or do the default shutdown if there is 643 * no type-specific method. 644 * 645 * We can only be called form a shutdown message, so we know we have 646 * a writer lock, and therefore exclusive access. It also means 647 * that we should not be on the work queue, but we check anyhow. 648 * 649 * Persistent node types must have a type-specific method which 650 * Allocates a new node in which case, this one is irretrievably going away, 651 * or cleans up anything it needs, and just makes the node valid again, 652 * in which case we allow the node to survive. 653 * 654 * XXX We need to think of how to tell a persistant node that we 655 * REALLY need to go away because the hardware has gone or we 656 * are rebooting.... etc. 657 */ 658 void 659 ng_rmnode(node_p node, hook_p dummy1, void *dummy2, int dummy3) 660 { 661 hook_p hook; 662 663 /* Check if it's already shutting down */ 664 if ((node->nd_flags & NGF_CLOSING) != 0) 665 return; 666 667 if (node == &ng_deadnode) { 668 printf ("shutdown called on deadnode\n"); 669 return; 670 } 671 672 /* Add an extra reference so it doesn't go away during this */ 673 NG_NODE_REF(node); 674 675 /* 676 * Mark it invalid so any newcomers know not to try use it 677 * Also add our own mark so we can't recurse 678 * note that NGF_INVALID does not do this as it's also set during 679 * creation 680 */ 681 node->nd_flags |= NGF_INVALID|NGF_CLOSING; 682 683 /* If node has its pre-shutdown method, then call it first*/ 684 if (node->nd_type && node->nd_type->close) 685 (*node->nd_type->close)(node); 686 687 /* Notify all remaining connected nodes to disconnect */ 688 while ((hook = LIST_FIRST(&node->nd_hooks)) != NULL) 689 ng_destroy_hook(hook); 690 691 /* 692 * Drain the input queue forceably. 693 * it has no hooks so what's it going to do, bleed on someone? 694 * Theoretically we came here from a queue entry that was added 695 * Just before the queue was closed, so it should be empty anyway. 696 * Also removes us from worklist if needed. 697 */ 698 ng_flush_input_queue(&node->nd_input_queue); 699 700 /* Ask the type if it has anything to do in this case */ 701 if (node->nd_type && node->nd_type->shutdown) { 702 (*node->nd_type->shutdown)(node); 703 if (NG_NODE_IS_VALID(node)) { 704 /* 705 * Well, blow me down if the node code hasn't declared 706 * that it doesn't want to die. 707 * Presumably it is a persistant node. 708 * If we REALLY want it to go away, 709 * e.g. hardware going away, 710 * Our caller should set NGF_REALLY_DIE in nd_flags. 711 */ 712 node->nd_flags &= ~(NGF_INVALID|NGF_CLOSING); 713 NG_NODE_UNREF(node); /* Assume they still have theirs */ 714 return; 715 } 716 } else { /* do the default thing */ 717 NG_NODE_UNREF(node); 718 } 719 720 ng_unname(node); /* basically a NOP these days */ 721 722 /* 723 * Remove extra reference, possibly the last 724 * Possible other holders of references may include 725 * timeout callouts, but theoretically the node's supposed to 726 * have cancelled them. Possibly hardware dependencies may 727 * force a driver to 'linger' with a reference. 728 */ 729 NG_NODE_UNREF(node); 730 } 731 732 #ifdef NETGRAPH_DEBUG 733 void 734 ng_ref_node(node_p node) 735 { 736 _NG_NODE_REF(node); 737 } 738 #endif 739 740 /* 741 * Remove a reference to the node, possibly the last. 742 * deadnode always acts as it it were the last. 743 */ 744 int 745 ng_unref_node(node_p node) 746 { 747 int v; 748 749 if (node == &ng_deadnode) { 750 return (0); 751 } 752 753 do { 754 v = node->nd_refs - 1; 755 } while (! atomic_cmpset_int(&node->nd_refs, v + 1, v)); 756 757 if (v == 0) { /* we were the last */ 758 759 mtx_lock(&ng_nodelist_mtx); 760 node->nd_type->refs--; /* XXX maybe should get types lock? */ 761 LIST_REMOVE(node, nd_nodes); 762 mtx_unlock(&ng_nodelist_mtx); 763 764 mtx_lock(&ng_idhash_mtx); 765 LIST_REMOVE(node, nd_idnodes); 766 mtx_unlock(&ng_idhash_mtx); 767 768 mtx_destroy(&node->nd_input_queue.q_mtx); 769 NG_FREE_NODE(node); 770 } 771 return (v); 772 } 773 774 /************************************************************************ 775 Node ID handling 776 ************************************************************************/ 777 static node_p 778 ng_ID2noderef(ng_ID_t ID) 779 { 780 node_p node; 781 mtx_lock(&ng_idhash_mtx); 782 NG_IDHASH_FIND(ID, node); 783 if(node) 784 NG_NODE_REF(node); 785 mtx_unlock(&ng_idhash_mtx); 786 return(node); 787 } 788 789 ng_ID_t 790 ng_node2ID(node_p node) 791 { 792 return (node ? NG_NODE_ID(node) : 0); 793 } 794 795 /************************************************************************ 796 Node name handling 797 ************************************************************************/ 798 799 /* 800 * Assign a node a name. Once assigned, the name cannot be changed. 801 */ 802 int 803 ng_name_node(node_p node, const char *name) 804 { 805 int i; 806 node_p node2; 807 808 /* Check the name is valid */ 809 for (i = 0; i < NG_NODESIZ; i++) { 810 if (name[i] == '\0' || name[i] == '.' || name[i] == ':') 811 break; 812 } 813 if (i == 0 || name[i] != '\0') { 814 TRAP_ERROR(); 815 return (EINVAL); 816 } 817 if (ng_decodeidname(name) != 0) { /* valid IDs not allowed here */ 818 TRAP_ERROR(); 819 return (EINVAL); 820 } 821 822 /* Check the name isn't already being used */ 823 if ((node2 = ng_name2noderef(node, name)) != NULL) { 824 NG_NODE_UNREF(node2); 825 TRAP_ERROR(); 826 return (EADDRINUSE); 827 } 828 829 /* copy it */ 830 strlcpy(NG_NODE_NAME(node), name, NG_NODESIZ); 831 832 return (0); 833 } 834 835 /* 836 * Find a node by absolute name. The name should NOT end with ':' 837 * The name "." means "this node" and "[xxx]" means "the node 838 * with ID (ie, at address) xxx". 839 * 840 * Returns the node if found, else NULL. 841 * Eventually should add something faster than a sequential search. 842 * Note it aquires a reference on the node so you can be sure it's still there. 843 */ 844 node_p 845 ng_name2noderef(node_p here, const char *name) 846 { 847 node_p node; 848 ng_ID_t temp; 849 850 /* "." means "this node" */ 851 if (strcmp(name, ".") == 0) { 852 NG_NODE_REF(here); 853 return(here); 854 } 855 856 /* Check for name-by-ID */ 857 if ((temp = ng_decodeidname(name)) != 0) { 858 return (ng_ID2noderef(temp)); 859 } 860 861 /* Find node by name */ 862 mtx_lock(&ng_nodelist_mtx); 863 LIST_FOREACH(node, &ng_nodelist, nd_nodes) { 864 if (NG_NODE_IS_VALID(node) 865 && NG_NODE_HAS_NAME(node) 866 && (strcmp(NG_NODE_NAME(node), name) == 0)) { 867 break; 868 } 869 } 870 if (node) 871 NG_NODE_REF(node); 872 mtx_unlock(&ng_nodelist_mtx); 873 return (node); 874 } 875 876 /* 877 * Decode an ID name, eg. "[f03034de]". Returns 0 if the 878 * string is not valid, otherwise returns the value. 879 */ 880 static ng_ID_t 881 ng_decodeidname(const char *name) 882 { 883 const int len = strlen(name); 884 char *eptr; 885 u_long val; 886 887 /* Check for proper length, brackets, no leading junk */ 888 if ((len < 3) 889 || (name[0] != '[') 890 || (name[len - 1] != ']') 891 || (!isxdigit(name[1]))) { 892 return ((ng_ID_t)0); 893 } 894 895 /* Decode number */ 896 val = strtoul(name + 1, &eptr, 16); 897 if ((eptr - name != len - 1) 898 || (val == ULONG_MAX) 899 || (val == 0)) { 900 return ((ng_ID_t)0); 901 } 902 return (ng_ID_t)val; 903 } 904 905 /* 906 * Remove a name from a node. This should only be called 907 * when shutting down and removing the node. 908 * IF we allow name changing this may be more resurected. 909 */ 910 void 911 ng_unname(node_p node) 912 { 913 } 914 915 /************************************************************************ 916 Hook routines 917 Names are not optional. Hooks are always connected, except for a 918 brief moment within these routines. On invalidation or during creation 919 they are connected to the 'dead' hook. 920 ************************************************************************/ 921 922 /* 923 * Remove a hook reference 924 */ 925 void 926 ng_unref_hook(hook_p hook) 927 { 928 int v; 929 930 if (hook == &ng_deadhook) { 931 return; 932 } 933 do { 934 v = hook->hk_refs; 935 } while (! atomic_cmpset_int(&hook->hk_refs, v, v - 1)); 936 937 if (v == 1) { /* we were the last */ 938 if (_NG_HOOK_NODE(hook)) { /* it'll probably be ng_deadnode */ 939 _NG_NODE_UNREF((_NG_HOOK_NODE(hook))); 940 hook->hk_node = NULL; 941 } 942 NG_FREE_HOOK(hook); 943 } 944 } 945 946 /* 947 * Add an unconnected hook to a node. Only used internally. 948 * Assumes node is locked. (XXX not yet true ) 949 */ 950 static int 951 ng_add_hook(node_p node, const char *name, hook_p *hookp) 952 { 953 hook_p hook; 954 int error = 0; 955 956 /* Check that the given name is good */ 957 if (name == NULL) { 958 TRAP_ERROR(); 959 return (EINVAL); 960 } 961 if (ng_findhook(node, name) != NULL) { 962 TRAP_ERROR(); 963 return (EEXIST); 964 } 965 966 /* Allocate the hook and link it up */ 967 NG_ALLOC_HOOK(hook); 968 if (hook == NULL) { 969 TRAP_ERROR(); 970 return (ENOMEM); 971 } 972 hook->hk_refs = 1; /* add a reference for us to return */ 973 hook->hk_flags = HK_INVALID; 974 hook->hk_peer = &ng_deadhook; /* start off this way */ 975 hook->hk_node = node; 976 NG_NODE_REF(node); /* each hook counts as a reference */ 977 978 /* Set hook name */ 979 strlcpy(NG_HOOK_NAME(hook), name, NG_HOOKSIZ); 980 981 /* 982 * Check if the node type code has something to say about it 983 * If it fails, the unref of the hook will also unref the node. 984 */ 985 if (node->nd_type->newhook != NULL) { 986 if ((error = (*node->nd_type->newhook)(node, hook, name))) { 987 NG_HOOK_UNREF(hook); /* this frees the hook */ 988 return (error); 989 } 990 } 991 /* 992 * The 'type' agrees so far, so go ahead and link it in. 993 * We'll ask again later when we actually connect the hooks. 994 */ 995 LIST_INSERT_HEAD(&node->nd_hooks, hook, hk_hooks); 996 node->nd_numhooks++; 997 NG_HOOK_REF(hook); /* one for the node */ 998 999 if (hookp) 1000 *hookp = hook; 1001 return (0); 1002 } 1003 1004 /* 1005 * Find a hook 1006 * 1007 * Node types may supply their own optimized routines for finding 1008 * hooks. If none is supplied, we just do a linear search. 1009 * XXX Possibly we should add a reference to the hook? 1010 */ 1011 hook_p 1012 ng_findhook(node_p node, const char *name) 1013 { 1014 hook_p hook; 1015 1016 if (node->nd_type->findhook != NULL) 1017 return (*node->nd_type->findhook)(node, name); 1018 LIST_FOREACH(hook, &node->nd_hooks, hk_hooks) { 1019 if (NG_HOOK_IS_VALID(hook) 1020 && (strcmp(NG_HOOK_NAME(hook), name) == 0)) 1021 return (hook); 1022 } 1023 return (NULL); 1024 } 1025 1026 /* 1027 * Destroy a hook 1028 * 1029 * As hooks are always attached, this really destroys two hooks. 1030 * The one given, and the one attached to it. Disconnect the hooks 1031 * from each other first. We reconnect the peer hook to the 'dead' 1032 * hook so that it can still exist after we depart. We then 1033 * send the peer its own destroy message. This ensures that we only 1034 * interact with the peer's structures when it is locked processing that 1035 * message. We hold a reference to the peer hook so we are guaranteed that 1036 * the peer hook and node are still going to exist until 1037 * we are finished there as the hook holds a ref on the node. 1038 * We run this same code again on the peer hook, but that time it is already 1039 * attached to the 'dead' hook. 1040 * 1041 * This routine is called at all stages of hook creation 1042 * on error detection and must be able to handle any such stage. 1043 */ 1044 void 1045 ng_destroy_hook(hook_p hook) 1046 { 1047 hook_p peer = NG_HOOK_PEER(hook); 1048 node_p node = NG_HOOK_NODE(hook); 1049 1050 if (hook == &ng_deadhook) { /* better safe than sorry */ 1051 printf("ng_destroy_hook called on deadhook\n"); 1052 return; 1053 } 1054 hook->hk_flags |= HK_INVALID; /* as soon as possible */ 1055 if (peer && (peer != &ng_deadhook)) { 1056 /* 1057 * Set the peer to point to ng_deadhook 1058 * from this moment on we are effectively independent it. 1059 * send it an rmhook message of it's own. 1060 */ 1061 peer->hk_peer = &ng_deadhook; /* They no longer know us */ 1062 hook->hk_peer = &ng_deadhook; /* Nor us, them */ 1063 if (NG_HOOK_NODE(peer) == &ng_deadnode) { 1064 /* 1065 * If it's already divorced from a node, 1066 * just free it. 1067 */ 1068 /* nothing */ 1069 } else { 1070 ng_rmhook_self(peer); /* Send it a surprise */ 1071 } 1072 NG_HOOK_UNREF(peer); /* account for peer link */ 1073 NG_HOOK_UNREF(hook); /* account for peer link */ 1074 } 1075 1076 /* 1077 * Remove the hook from the node's list to avoid possible recursion 1078 * in case the disconnection results in node shutdown. 1079 */ 1080 if (node == &ng_deadnode) { /* happens if called from ng_con_nodes() */ 1081 return; 1082 } 1083 LIST_REMOVE(hook, hk_hooks); 1084 node->nd_numhooks--; 1085 if (node->nd_type->disconnect) { 1086 /* 1087 * The type handler may elect to destroy the node so don't 1088 * trust its existance after this point. (except 1089 * that we still hold a reference on it. (which we 1090 * inherrited from the hook we are destroying) 1091 */ 1092 (*node->nd_type->disconnect) (hook); 1093 } 1094 1095 /* 1096 * Note that because we will point to ng_deadnode, the original node 1097 * is not decremented automatically so we do that manually. 1098 */ 1099 _NG_HOOK_NODE(hook) = &ng_deadnode; 1100 NG_NODE_UNREF(node); /* We no longer point to it so adjust count */ 1101 NG_HOOK_UNREF(hook); /* Account for linkage (in list) to node */ 1102 } 1103 1104 /* 1105 * Take two hooks on a node and merge the connection so that the given node 1106 * is effectively bypassed. 1107 */ 1108 int 1109 ng_bypass(hook_p hook1, hook_p hook2) 1110 { 1111 if (hook1->hk_node != hook2->hk_node) { 1112 TRAP_ERROR(); 1113 return (EINVAL); 1114 } 1115 hook1->hk_peer->hk_peer = hook2->hk_peer; 1116 hook2->hk_peer->hk_peer = hook1->hk_peer; 1117 1118 hook1->hk_peer = &ng_deadhook; 1119 hook2->hk_peer = &ng_deadhook; 1120 1121 /* XXX If we ever cache methods on hooks update them as well */ 1122 ng_destroy_hook(hook1); 1123 ng_destroy_hook(hook2); 1124 return (0); 1125 } 1126 1127 /* 1128 * Install a new netgraph type 1129 */ 1130 int 1131 ng_newtype(struct ng_type *tp) 1132 { 1133 const size_t namelen = strlen(tp->name); 1134 1135 /* Check version and type name fields */ 1136 if ((tp->version != NG_ABI_VERSION) 1137 || (namelen == 0) 1138 || (namelen >= NG_TYPESIZ)) { 1139 TRAP_ERROR(); 1140 if (tp->version != NG_ABI_VERSION) { 1141 printf("Netgraph: Node type rejected. ABI mismatch. Suggest recompile\n"); 1142 } 1143 return (EINVAL); 1144 } 1145 1146 /* Check for name collision */ 1147 if (ng_findtype(tp->name) != NULL) { 1148 TRAP_ERROR(); 1149 return (EEXIST); 1150 } 1151 1152 1153 /* Link in new type */ 1154 mtx_lock(&ng_typelist_mtx); 1155 LIST_INSERT_HEAD(&ng_typelist, tp, types); 1156 tp->refs = 1; /* first ref is linked list */ 1157 mtx_unlock(&ng_typelist_mtx); 1158 return (0); 1159 } 1160 1161 /* 1162 * unlink a netgraph type 1163 * If no examples exist 1164 */ 1165 int 1166 ng_rmtype(struct ng_type *tp) 1167 { 1168 /* Check for name collision */ 1169 if (tp->refs != 1) { 1170 TRAP_ERROR(); 1171 return (EBUSY); 1172 } 1173 1174 /* Unlink type */ 1175 mtx_lock(&ng_typelist_mtx); 1176 LIST_REMOVE(tp, types); 1177 mtx_unlock(&ng_typelist_mtx); 1178 return (0); 1179 } 1180 1181 /* 1182 * Look for a type of the name given 1183 */ 1184 struct ng_type * 1185 ng_findtype(const char *typename) 1186 { 1187 struct ng_type *type; 1188 1189 mtx_lock(&ng_typelist_mtx); 1190 LIST_FOREACH(type, &ng_typelist, types) { 1191 if (strcmp(type->name, typename) == 0) 1192 break; 1193 } 1194 mtx_unlock(&ng_typelist_mtx); 1195 return (type); 1196 } 1197 1198 /************************************************************************ 1199 Composite routines 1200 ************************************************************************/ 1201 /* 1202 * Connect two nodes using the specified hooks, using queued functions. 1203 */ 1204 static void 1205 ng_con_part3(node_p node, hook_p hook, void *arg1, int arg2) 1206 { 1207 1208 /* 1209 * When we run, we know that the node 'node' is locked for us. 1210 * Our caller has a reference on the hook. 1211 * Our caller has a reference on the node. 1212 * (In this case our caller is ng_apply_item() ). 1213 * The peer hook has a reference on the hook. 1214 * We are all set up except for the final call to the node, and 1215 * the clearing of the INVALID flag. 1216 */ 1217 if (NG_HOOK_NODE(hook) == &ng_deadnode) { 1218 /* 1219 * The node must have been freed again since we last visited 1220 * here. ng_destry_hook() has this effect but nothing else does. 1221 * We should just release our references and 1222 * free anything we can think of. 1223 * Since we know it's been destroyed, and it's our caller 1224 * that holds the references, just return. 1225 */ 1226 return ; 1227 } 1228 if (hook->hk_node->nd_type->connect) { 1229 if ((*hook->hk_node->nd_type->connect) (hook)) { 1230 ng_destroy_hook(hook); /* also zaps peer */ 1231 printf("failed in ng_con_part3()\n"); 1232 return ; 1233 } 1234 } 1235 /* 1236 * XXX this is wrong for SMP. Possibly we need 1237 * to separate out 'create' and 'invalid' flags. 1238 * should only set flags on hooks we have locked under our node. 1239 */ 1240 hook->hk_flags &= ~HK_INVALID; 1241 return ; 1242 } 1243 1244 static void 1245 ng_con_part2(node_p node, hook_p hook, void *arg1, int arg2) 1246 { 1247 1248 /* 1249 * When we run, we know that the node 'node' is locked for us. 1250 * Our caller has a reference on the hook. 1251 * Our caller has a reference on the node. 1252 * (In this case our caller is ng_apply_item() ). 1253 * The peer hook has a reference on the hook. 1254 * our node pointer points to the 'dead' node. 1255 * First check the hook name is unique. 1256 * Should not happen because we checked before queueing this. 1257 */ 1258 if (ng_findhook(node, NG_HOOK_NAME(hook)) != NULL) { 1259 TRAP_ERROR(); 1260 ng_destroy_hook(hook); /* should destroy peer too */ 1261 printf("failed in ng_con_part2()\n"); 1262 return ; 1263 } 1264 /* 1265 * Check if the node type code has something to say about it 1266 * If it fails, the unref of the hook will also unref the attached node, 1267 * however since that node is 'ng_deadnode' this will do nothing. 1268 * The peer hook will also be destroyed. 1269 */ 1270 if (node->nd_type->newhook != NULL) { 1271 if ((*node->nd_type->newhook)(node, hook, hook->hk_name)) { 1272 ng_destroy_hook(hook); /* should destroy peer too */ 1273 printf("failed in ng_con_part2()\n"); 1274 return ; 1275 } 1276 } 1277 1278 /* 1279 * The 'type' agrees so far, so go ahead and link it in. 1280 * We'll ask again later when we actually connect the hooks. 1281 */ 1282 hook->hk_node = node; /* just overwrite ng_deadnode */ 1283 NG_NODE_REF(node); /* each hook counts as a reference */ 1284 LIST_INSERT_HEAD(&node->nd_hooks, hook, hk_hooks); 1285 node->nd_numhooks++; 1286 NG_HOOK_REF(hook); /* one for the node */ 1287 1288 /* 1289 * We now have a symetrical situation, where both hooks have been 1290 * linked to their nodes, the newhook methods have been called 1291 * And the references are all correct. The hooks are still marked 1292 * as invalid, as we have not called the 'connect' methods 1293 * yet. 1294 * We can call the local one immediatly as we have the 1295 * node locked, but we need to queue the remote one. 1296 */ 1297 if (hook->hk_node->nd_type->connect) { 1298 if ((*hook->hk_node->nd_type->connect) (hook)) { 1299 ng_destroy_hook(hook); /* also zaps peer */ 1300 printf("failed in ng_con_part2(A)\n"); 1301 return ; 1302 } 1303 } 1304 if (ng_send_fn(hook->hk_peer->hk_node, hook->hk_peer, 1305 &ng_con_part3, arg1, arg2)) { 1306 printf("failed in ng_con_part2(B)"); 1307 ng_destroy_hook(hook); /* also zaps peer */ 1308 return ; 1309 } 1310 hook->hk_flags &= ~HK_INVALID; /* need both to be able to work */ 1311 return ; 1312 } 1313 1314 /* 1315 * Connect this node with another node. We assume that this node is 1316 * currently locked, as we are only called from an NGM_CONNECT message. 1317 */ 1318 static int 1319 ng_con_nodes(node_p node, const char *name, node_p node2, const char *name2) 1320 { 1321 int error; 1322 hook_p hook; 1323 hook_p hook2; 1324 1325 if (ng_findhook(node2, name2) != NULL) { 1326 return(EEXIST); 1327 } 1328 if ((error = ng_add_hook(node, name, &hook))) /* gives us a ref */ 1329 return (error); 1330 /* Allocate the other hook and link it up */ 1331 NG_ALLOC_HOOK(hook2); 1332 if (hook == NULL) { 1333 TRAP_ERROR(); 1334 ng_destroy_hook(hook); /* XXX check ref counts so far */ 1335 NG_HOOK_UNREF(hook); /* including our ref */ 1336 return (ENOMEM); 1337 } 1338 hook2->hk_refs = 1; /* start with a reference for us. */ 1339 hook2->hk_flags = HK_INVALID; 1340 hook2->hk_peer = hook; /* Link the two together */ 1341 hook->hk_peer = hook2; 1342 NG_HOOK_REF(hook); /* Add a ref for the peer to each*/ 1343 NG_HOOK_REF(hook2); 1344 hook2->hk_node = &ng_deadnode; 1345 strlcpy(NG_HOOK_NAME(hook2), name2, NG_HOOKSIZ); 1346 1347 /* 1348 * Queue the function above. 1349 * Procesing continues in that function in the lock context of 1350 * the other node. 1351 */ 1352 ng_send_fn(node2, hook2, &ng_con_part2, NULL, 0); 1353 1354 NG_HOOK_UNREF(hook); /* Let each hook go if it wants to */ 1355 NG_HOOK_UNREF(hook2); 1356 return (0); 1357 } 1358 1359 /* 1360 * Make a peer and connect. 1361 * We assume that the local node is locked. 1362 * The new node probably doesn't need a lock until 1363 * it has a hook, because it cannot really have any work until then, 1364 * but we should think about it a bit more. 1365 * 1366 * The problem may come if the other node also fires up 1367 * some hardware or a timer or some other source of activation, 1368 * also it may already get a command msg via it's ID. 1369 * 1370 * We could use the same method as ng_con_nodes() but we'd have 1371 * to add ability to remove the node when failing. (Not hard, just 1372 * make arg1 point to the node to remove). 1373 * Unless of course we just ignore failure to connect and leave 1374 * an unconnected node? 1375 */ 1376 static int 1377 ng_mkpeer(node_p node, const char *name, const char *name2, char *type) 1378 { 1379 node_p node2; 1380 hook_p hook1; 1381 hook_p hook2; 1382 int error; 1383 1384 if ((error = ng_make_node(type, &node2))) { 1385 return (error); 1386 } 1387 1388 if ((error = ng_add_hook(node, name, &hook1))) { /* gives us a ref */ 1389 ng_rmnode(node2, NULL, NULL, 0); 1390 return (error); 1391 } 1392 1393 if ((error = ng_add_hook(node2, name2, &hook2))) { 1394 ng_rmnode(node2, NULL, NULL, 0); 1395 ng_destroy_hook(hook1); 1396 NG_HOOK_UNREF(hook1); 1397 return (error); 1398 } 1399 1400 /* 1401 * Actually link the two hooks together. 1402 */ 1403 hook1->hk_peer = hook2; 1404 hook2->hk_peer = hook1; 1405 1406 /* Each hook is referenced by the other */ 1407 NG_HOOK_REF(hook1); 1408 NG_HOOK_REF(hook2); 1409 1410 /* Give each node the opportunity to veto the pending connection */ 1411 if (hook1->hk_node->nd_type->connect) { 1412 error = (*hook1->hk_node->nd_type->connect) (hook1); 1413 } 1414 1415 if ((error == 0) && hook2->hk_node->nd_type->connect) { 1416 error = (*hook2->hk_node->nd_type->connect) (hook2); 1417 1418 } 1419 1420 /* 1421 * drop the references we were holding on the two hooks. 1422 */ 1423 if (error) { 1424 ng_destroy_hook(hook2); /* also zaps hook1 */ 1425 ng_rmnode(node2, NULL, NULL, 0); 1426 } else { 1427 /* As a last act, allow the hooks to be used */ 1428 hook1->hk_flags &= ~HK_INVALID; 1429 hook2->hk_flags &= ~HK_INVALID; 1430 } 1431 NG_HOOK_UNREF(hook1); 1432 NG_HOOK_UNREF(hook2); 1433 return (error); 1434 } 1435 1436 /************************************************************************ 1437 Utility routines to send self messages 1438 ************************************************************************/ 1439 1440 /* Shut this node down as soon as everyone is clear of it */ 1441 /* Should add arg "immediatly" to jump the queue */ 1442 int 1443 ng_rmnode_self(node_p node) 1444 { 1445 int error; 1446 1447 if (node == &ng_deadnode) 1448 return (0); 1449 node->nd_flags |= NGF_INVALID; 1450 if (node->nd_flags & NGF_CLOSING) 1451 return (0); 1452 1453 error = ng_send_fn(node, NULL, &ng_rmnode, NULL, 0); 1454 return (error); 1455 } 1456 1457 static void 1458 ng_rmhook_part2(node_p node, hook_p hook, void *arg1, int arg2) 1459 { 1460 ng_destroy_hook(hook); 1461 return ; 1462 } 1463 1464 int 1465 ng_rmhook_self(hook_p hook) 1466 { 1467 int error; 1468 node_p node = NG_HOOK_NODE(hook); 1469 1470 if (node == &ng_deadnode) 1471 return (0); 1472 1473 error = ng_send_fn(node, hook, &ng_rmhook_part2, NULL, 0); 1474 return (error); 1475 } 1476 1477 /*********************************************************************** 1478 * Parse and verify a string of the form: <NODE:><PATH> 1479 * 1480 * Such a string can refer to a specific node or a specific hook 1481 * on a specific node, depending on how you look at it. In the 1482 * latter case, the PATH component must not end in a dot. 1483 * 1484 * Both <NODE:> and <PATH> are optional. The <PATH> is a string 1485 * of hook names separated by dots. This breaks out the original 1486 * string, setting *nodep to "NODE" (or NULL if none) and *pathp 1487 * to "PATH" (or NULL if degenerate). Also, *hookp will point to 1488 * the final hook component of <PATH>, if any, otherwise NULL. 1489 * 1490 * This returns -1 if the path is malformed. The char ** are optional. 1491 ***********************************************************************/ 1492 int 1493 ng_path_parse(char *addr, char **nodep, char **pathp, char **hookp) 1494 { 1495 char *node, *path, *hook; 1496 int k; 1497 1498 /* 1499 * Extract absolute NODE, if any 1500 */ 1501 for (path = addr; *path && *path != ':'; path++); 1502 if (*path) { 1503 node = addr; /* Here's the NODE */ 1504 *path++ = '\0'; /* Here's the PATH */ 1505 1506 /* Node name must not be empty */ 1507 if (!*node) 1508 return -1; 1509 1510 /* A name of "." is OK; otherwise '.' not allowed */ 1511 if (strcmp(node, ".") != 0) { 1512 for (k = 0; node[k]; k++) 1513 if (node[k] == '.') 1514 return -1; 1515 } 1516 } else { 1517 node = NULL; /* No absolute NODE */ 1518 path = addr; /* Here's the PATH */ 1519 } 1520 1521 /* Snoop for illegal characters in PATH */ 1522 for (k = 0; path[k]; k++) 1523 if (path[k] == ':') 1524 return -1; 1525 1526 /* Check for no repeated dots in PATH */ 1527 for (k = 0; path[k]; k++) 1528 if (path[k] == '.' && path[k + 1] == '.') 1529 return -1; 1530 1531 /* Remove extra (degenerate) dots from beginning or end of PATH */ 1532 if (path[0] == '.') 1533 path++; 1534 if (*path && path[strlen(path) - 1] == '.') 1535 path[strlen(path) - 1] = 0; 1536 1537 /* If PATH has a dot, then we're not talking about a hook */ 1538 if (*path) { 1539 for (hook = path, k = 0; path[k]; k++) 1540 if (path[k] == '.') { 1541 hook = NULL; 1542 break; 1543 } 1544 } else 1545 path = hook = NULL; 1546 1547 /* Done */ 1548 if (nodep) 1549 *nodep = node; 1550 if (pathp) 1551 *pathp = path; 1552 if (hookp) 1553 *hookp = hook; 1554 return (0); 1555 } 1556 1557 /* 1558 * Given a path, which may be absolute or relative, and a starting node, 1559 * return the destination node. 1560 */ 1561 int 1562 ng_path2noderef(node_p here, const char *address, 1563 node_p *destp, hook_p *lasthook) 1564 { 1565 char fullpath[NG_PATHSIZ]; 1566 char *nodename, *path, pbuf[2]; 1567 node_p node, oldnode; 1568 char *cp; 1569 hook_p hook = NULL; 1570 1571 /* Initialize */ 1572 if (destp == NULL) { 1573 TRAP_ERROR(); 1574 return EINVAL; 1575 } 1576 *destp = NULL; 1577 1578 /* Make a writable copy of address for ng_path_parse() */ 1579 strncpy(fullpath, address, sizeof(fullpath) - 1); 1580 fullpath[sizeof(fullpath) - 1] = '\0'; 1581 1582 /* Parse out node and sequence of hooks */ 1583 if (ng_path_parse(fullpath, &nodename, &path, NULL) < 0) { 1584 TRAP_ERROR(); 1585 return EINVAL; 1586 } 1587 if (path == NULL) { 1588 pbuf[0] = '.'; /* Needs to be writable */ 1589 pbuf[1] = '\0'; 1590 path = pbuf; 1591 } 1592 1593 /* 1594 * For an absolute address, jump to the starting node. 1595 * Note that this holds a reference on the node for us. 1596 * Don't forget to drop the reference if we don't need it. 1597 */ 1598 if (nodename) { 1599 node = ng_name2noderef(here, nodename); 1600 if (node == NULL) { 1601 TRAP_ERROR(); 1602 return (ENOENT); 1603 } 1604 } else { 1605 if (here == NULL) { 1606 TRAP_ERROR(); 1607 return (EINVAL); 1608 } 1609 node = here; 1610 NG_NODE_REF(node); 1611 } 1612 1613 /* 1614 * Now follow the sequence of hooks 1615 * XXX 1616 * We actually cannot guarantee that the sequence 1617 * is not being demolished as we crawl along it 1618 * without extra-ordinary locking etc. 1619 * So this is a bit dodgy to say the least. 1620 * We can probably hold up some things by holding 1621 * the nodelist mutex for the time of this 1622 * crawl if we wanted.. At least that way we wouldn't have to 1623 * worry about the nodes dissappearing, but the hooks would still 1624 * be a problem. 1625 */ 1626 for (cp = path; node != NULL && *cp != '\0'; ) { 1627 char *segment; 1628 1629 /* 1630 * Break out the next path segment. Replace the dot we just 1631 * found with a NUL; "cp" points to the next segment (or the 1632 * NUL at the end). 1633 */ 1634 for (segment = cp; *cp != '\0'; cp++) { 1635 if (*cp == '.') { 1636 *cp++ = '\0'; 1637 break; 1638 } 1639 } 1640 1641 /* Empty segment */ 1642 if (*segment == '\0') 1643 continue; 1644 1645 /* We have a segment, so look for a hook by that name */ 1646 hook = ng_findhook(node, segment); 1647 1648 /* Can't get there from here... */ 1649 if (hook == NULL 1650 || NG_HOOK_PEER(hook) == NULL 1651 || NG_HOOK_NOT_VALID(hook) 1652 || NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook))) { 1653 TRAP_ERROR(); 1654 NG_NODE_UNREF(node); 1655 #if 0 1656 printf("hooknotvalid %s %s %d %d %d %d ", 1657 path, 1658 segment, 1659 hook == NULL, 1660 NG_HOOK_PEER(hook) == NULL, 1661 NG_HOOK_NOT_VALID(hook), 1662 NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook))); 1663 #endif 1664 return (ENOENT); 1665 } 1666 1667 /* 1668 * Hop on over to the next node 1669 * XXX 1670 * Big race conditions here as hooks and nodes go away 1671 * *** Idea.. store an ng_ID_t in each hook and use that 1672 * instead of the direct hook in this crawl? 1673 */ 1674 oldnode = node; 1675 if ((node = NG_PEER_NODE(hook))) 1676 NG_NODE_REF(node); /* XXX RACE */ 1677 NG_NODE_UNREF(oldnode); /* XXX another race */ 1678 if (NG_NODE_NOT_VALID(node)) { 1679 NG_NODE_UNREF(node); /* XXX more races */ 1680 node = NULL; 1681 } 1682 } 1683 1684 /* If node somehow missing, fail here (probably this is not needed) */ 1685 if (node == NULL) { 1686 TRAP_ERROR(); 1687 return (ENXIO); 1688 } 1689 1690 /* Done */ 1691 *destp = node; 1692 if (lasthook != NULL) 1693 *lasthook = (hook ? NG_HOOK_PEER(hook) : NULL); 1694 return (0); 1695 } 1696 1697 /***************************************************************\ 1698 * Input queue handling. 1699 * All activities are submitted to the node via the input queue 1700 * which implements a multiple-reader/single-writer gate. 1701 * Items which cannot be handled immeditly are queued. 1702 * 1703 * read-write queue locking inline functions * 1704 \***************************************************************/ 1705 1706 static __inline item_p ng_dequeue(struct ng_queue * ngq); 1707 static __inline item_p ng_acquire_read(struct ng_queue * ngq, 1708 item_p item); 1709 static __inline item_p ng_acquire_write(struct ng_queue * ngq, 1710 item_p item); 1711 static __inline void ng_leave_read(struct ng_queue * ngq); 1712 static __inline void ng_leave_write(struct ng_queue * ngq); 1713 static __inline void ng_queue_rw(struct ng_queue * ngq, 1714 item_p item, int rw); 1715 1716 /* 1717 * Definition of the bits fields in the ng_queue flag word. 1718 * Defined here rather than in netgraph.h because no-one should fiddle 1719 * with them. 1720 * 1721 * The ordering here may be important! don't shuffle these. 1722 */ 1723 /*- 1724 Safety Barrier--------+ (adjustable to suit taste) (not used yet) 1725 | 1726 V 1727 +-------+-------+-------+-------+-------+-------+-------+-------+ 1728 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 1729 | |A|c|t|i|v|e| |R|e|a|d|e|r| |C|o|u|n|t| | | | | | | | | |R|A|W| 1730 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |P|W|P| 1731 +-------+-------+-------+-------+-------+-------+-------+-------+ 1732 \___________________________ ____________________________/ | | | 1733 V | | | 1734 [active reader count] | | | 1735 | | | 1736 Read Pending ------------------------------------+ | | 1737 | | 1738 Active Writer -------------------------------------+ | 1739 | 1740 Write Pending ---------------------------------------+ 1741 1742 1743 */ 1744 #define WRITE_PENDING 0x00000001 1745 #define WRITER_ACTIVE 0x00000002 1746 #define READ_PENDING 0x00000004 1747 #define READER_INCREMENT 0x00000008 1748 #define READER_MASK 0xfffffff0 /* Not valid if WRITER_ACTIVE is set */ 1749 #define SAFETY_BARRIER 0x00100000 /* 64K items queued should be enough */ 1750 1751 /* Defines of more elaborate states on the queue */ 1752 /* Mask of bits a read cares about */ 1753 #define NGQ_RMASK (WRITE_PENDING|WRITER_ACTIVE|READ_PENDING) 1754 1755 /* Mask of bits a write cares about */ 1756 #define NGQ_WMASK (NGQ_RMASK|READER_MASK) 1757 1758 /* tests to decide if we could get a read or write off the queue */ 1759 #define CAN_GET_READ(flag) ((flag & NGQ_RMASK) == READ_PENDING) 1760 #define CAN_GET_WRITE(flag) ((flag & NGQ_WMASK) == WRITE_PENDING) 1761 1762 /* Is there a chance of getting ANY work off the queue? */ 1763 #define CAN_GET_WORK(flag) (CAN_GET_READ(flag) || CAN_GET_WRITE(flag)) 1764 1765 /* 1766 * Taking into account the current state of the queue and node, possibly take 1767 * the next entry off the queue and return it. Return NULL if there was 1768 * nothing we could return, either because there really was nothing there, or 1769 * because the node was in a state where it cannot yet process the next item 1770 * on the queue. 1771 * 1772 * This MUST MUST MUST be called with the mutex held. 1773 */ 1774 static __inline item_p 1775 ng_dequeue(struct ng_queue *ngq) 1776 { 1777 item_p item; 1778 u_int add_arg; 1779 1780 if (CAN_GET_READ(ngq->q_flags)) { 1781 /* 1782 * Head of queue is a reader and we have no write active. 1783 * We don't care how many readers are already active. 1784 * Adjust the flags for the item we are about to dequeue. 1785 * Add the correct increment for the reader count as well. 1786 */ 1787 add_arg = (READER_INCREMENT - READ_PENDING); 1788 } else if (CAN_GET_WRITE(ngq->q_flags)) { 1789 /* 1790 * There is a pending write, no readers and no active writer. 1791 * This means we can go ahead with the pending writer. Note 1792 * the fact that we now have a writer, ready for when we take 1793 * it off the queue. 1794 * 1795 * We don't need to worry about a possible collision with the 1796 * fasttrack reader. 1797 * 1798 * The fasttrack thread may take a long time to discover that we 1799 * are running so we would have an inconsistent state in the 1800 * flags for a while. Since we ignore the reader count 1801 * entirely when the WRITER_ACTIVE flag is set, this should 1802 * not matter (in fact it is defined that way). If it tests 1803 * the flag before this operation, the WRITE_PENDING flag 1804 * will make it fail, and if it tests it later, the 1805 * WRITER_ACTIVE flag will do the same. If it is SO slow that 1806 * we have actually completed the operation, and neither flag 1807 * is set (nor the READ_PENDING) by the time that it tests 1808 * the flags, then it is actually ok for it to continue. If 1809 * it completes and we've finished and the read pending is 1810 * set it still fails. 1811 * 1812 * So we can just ignore it, as long as we can ensure that the 1813 * transition from WRITE_PENDING state to the WRITER_ACTIVE 1814 * state is atomic. 1815 * 1816 * After failing, first it will be held back by the mutex, then 1817 * when it can proceed, it will queue its request, then it 1818 * would arrive at this function. Usually it will have to 1819 * leave empty handed because the ACTIVE WRITER bit will be 1820 * set. 1821 * 1822 * Adjust the flags for the item we are about to dequeue 1823 * and for the new active writer. 1824 */ 1825 add_arg = (WRITER_ACTIVE - WRITE_PENDING); 1826 /* 1827 * We want to write "active writer, no readers " Now go make 1828 * it true. In fact there may be a number in the readers 1829 * count but we know it is not true and will be fixed soon. 1830 * We will fix the flags for the next pending entry in a 1831 * moment. 1832 */ 1833 } else { 1834 /* 1835 * We can't dequeue anything.. return and say so. Probably we 1836 * have a write pending and the readers count is non zero. If 1837 * we got here because a reader hit us just at the wrong 1838 * moment with the fasttrack code, and put us in a strange 1839 * state, then it will be through in just a moment, (as soon 1840 * as we release the mutex) and keep things moving. 1841 * Make sure we remove ourselves from the work queue. 1842 */ 1843 ng_worklist_remove(ngq->q_node); 1844 return (0); 1845 } 1846 1847 /* 1848 * Now we dequeue the request (whatever it may be) and correct the 1849 * pending flags and the next and last pointers. 1850 */ 1851 item = ngq->queue; 1852 ngq->queue = item->el_next; 1853 if (ngq->last == &(item->el_next)) { 1854 /* 1855 * that was the last entry in the queue so set the 'last 1856 * pointer up correctly and make sure the pending flags are 1857 * clear. 1858 */ 1859 ngq->last = &(ngq->queue); 1860 /* 1861 * Whatever flag was set will be cleared and 1862 * the new acive field will be set by the add as well, 1863 * so we don't need to change add_arg. 1864 * But we know we don't need to be on the work list. 1865 */ 1866 atomic_add_long(&ngq->q_flags, add_arg); 1867 ng_worklist_remove(ngq->q_node); 1868 } else { 1869 /* 1870 * Since there is something on the queue, note what it is 1871 * in the flags word. 1872 */ 1873 if ((ngq->queue->el_flags & NGQF_RW) == NGQF_READER) { 1874 add_arg += READ_PENDING; 1875 } else { 1876 add_arg += WRITE_PENDING; 1877 } 1878 atomic_add_long(&ngq->q_flags, add_arg); 1879 /* 1880 * If we see more doable work, make sure we are 1881 * on the work queue. 1882 */ 1883 if (CAN_GET_WORK(ngq->q_flags)) { 1884 ng_setisr(ngq->q_node); 1885 } 1886 } 1887 /* 1888 * We have successfully cleared the old pending flag, set the new one 1889 * if it is needed, and incremented the appropriate active field. 1890 * (all in one atomic addition.. ) 1891 */ 1892 return (item); 1893 } 1894 1895 /* 1896 * Queue a packet to be picked up by someone else. 1897 * We really don't care who, but we can't or don't want to hang around 1898 * to process it ourselves. We are probably an interrupt routine.. 1899 * 1 = writer, 0 = reader 1900 */ 1901 #define NGQRW_R 0 1902 #define NGQRW_W 1 1903 static __inline void 1904 ng_queue_rw(struct ng_queue * ngq, item_p item, int rw) 1905 { 1906 item->el_next = NULL; /* maybe not needed */ 1907 *ngq->last = item; 1908 /* 1909 * If it was the first item in the queue then we need to 1910 * set the last pointer and the type flags. 1911 */ 1912 if (ngq->last == &(ngq->queue)) { 1913 /* 1914 * When called with constants for rw, the optimiser will 1915 * remove the unneeded branch below. 1916 */ 1917 if (rw == NGQRW_W) { 1918 atomic_add_long(&ngq->q_flags, WRITE_PENDING); 1919 } else { 1920 atomic_add_long(&ngq->q_flags, READ_PENDING); 1921 } 1922 } 1923 ngq->last = &(item->el_next); 1924 } 1925 1926 1927 /* 1928 * This function 'cheats' in that it first tries to 'grab' the use of the 1929 * node, without going through the mutex. We can do this becasue of the 1930 * semantics of the lock. The semantics include a clause that says that the 1931 * value of the readers count is invalid if the WRITER_ACTIVE flag is set. It 1932 * also says that the WRITER_ACTIVE flag cannot be set if the readers count 1933 * is not zero. Note that this talks about what is valid to SET the 1934 * WRITER_ACTIVE flag, because from the moment it is set, the value if the 1935 * reader count is immaterial, and not valid. The two 'pending' flags have a 1936 * similar effect, in that If they are orthogonal to the two active fields in 1937 * how they are set, but if either is set, the attempted 'grab' need to be 1938 * backed out because there is earlier work, and we maintain ordering in the 1939 * queue. The result of this is that the reader request can try obtain use of 1940 * the node with only a single atomic addition, and without any of the mutex 1941 * overhead. If this fails the operation degenerates to the same as for other 1942 * cases. 1943 * 1944 */ 1945 static __inline item_p 1946 ng_acquire_read(struct ng_queue *ngq, item_p item) 1947 { 1948 1949 /* ######### Hack alert ######### */ 1950 atomic_add_long(&ngq->q_flags, READER_INCREMENT); 1951 if ((ngq->q_flags & NGQ_RMASK) == 0) { 1952 /* Successfully grabbed node */ 1953 return (item); 1954 } 1955 /* undo the damage if we didn't succeed */ 1956 atomic_subtract_long(&ngq->q_flags, READER_INCREMENT); 1957 1958 /* ######### End Hack alert ######### */ 1959 mtx_lock_spin((&ngq->q_mtx)); 1960 /* 1961 * Try again. Another processor (or interrupt for that matter) may 1962 * have removed the last queued item that was stopping us from 1963 * running, between the previous test, and the moment that we took 1964 * the mutex. (Or maybe a writer completed.) 1965 */ 1966 if ((ngq->q_flags & NGQ_RMASK) == 0) { 1967 atomic_add_long(&ngq->q_flags, READER_INCREMENT); 1968 mtx_unlock_spin((&ngq->q_mtx)); 1969 return (item); 1970 } 1971 1972 /* 1973 * and queue the request for later. 1974 */ 1975 item->el_flags |= NGQF_READER; 1976 ng_queue_rw(ngq, item, NGQRW_R); 1977 1978 /* 1979 * Ok, so that's the item successfully queued for later. So now we 1980 * see if we can dequeue something to run instead. 1981 */ 1982 item = ng_dequeue(ngq); 1983 mtx_unlock_spin(&(ngq->q_mtx)); 1984 return (item); 1985 } 1986 1987 static __inline item_p 1988 ng_acquire_write(struct ng_queue *ngq, item_p item) 1989 { 1990 restart: 1991 mtx_lock_spin(&(ngq->q_mtx)); 1992 /* 1993 * If there are no readers, no writer, and no pending packets, then 1994 * we can just go ahead. In all other situations we need to queue the 1995 * request 1996 */ 1997 if ((ngq->q_flags & NGQ_WMASK) == 0) { 1998 atomic_add_long(&ngq->q_flags, WRITER_ACTIVE); 1999 mtx_unlock_spin((&ngq->q_mtx)); 2000 if (ngq->q_flags & READER_MASK) { 2001 /* Collision with fast-track reader */ 2002 atomic_subtract_long(&ngq->q_flags, WRITER_ACTIVE); 2003 goto restart; 2004 } 2005 return (item); 2006 } 2007 2008 /* 2009 * and queue the request for later. 2010 */ 2011 item->el_flags &= ~NGQF_RW; 2012 ng_queue_rw(ngq, item, NGQRW_W); 2013 2014 /* 2015 * Ok, so that's the item successfully queued for later. So now we 2016 * see if we can dequeue something to run instead. 2017 */ 2018 item = ng_dequeue(ngq); 2019 mtx_unlock_spin(&(ngq->q_mtx)); 2020 return (item); 2021 } 2022 2023 static __inline void 2024 ng_leave_read(struct ng_queue *ngq) 2025 { 2026 atomic_subtract_long(&ngq->q_flags, READER_INCREMENT); 2027 } 2028 2029 static __inline void 2030 ng_leave_write(struct ng_queue *ngq) 2031 { 2032 atomic_subtract_long(&ngq->q_flags, WRITER_ACTIVE); 2033 } 2034 2035 static void 2036 ng_flush_input_queue(struct ng_queue * ngq) 2037 { 2038 item_p item; 2039 u_int add_arg; 2040 mtx_lock_spin(&ngq->q_mtx); 2041 for (;;) { 2042 /* Now take a look at what's on the queue */ 2043 if (ngq->q_flags & READ_PENDING) { 2044 add_arg = -READ_PENDING; 2045 } else if (ngq->q_flags & WRITE_PENDING) { 2046 add_arg = -WRITE_PENDING; 2047 } else { 2048 break; 2049 } 2050 2051 item = ngq->queue; 2052 ngq->queue = item->el_next; 2053 if (ngq->last == &(item->el_next)) { 2054 ngq->last = &(ngq->queue); 2055 } else { 2056 if ((ngq->queue->el_flags & NGQF_RW) == NGQF_READER) { 2057 add_arg += READ_PENDING; 2058 } else { 2059 add_arg += WRITE_PENDING; 2060 } 2061 } 2062 atomic_add_long(&ngq->q_flags, add_arg); 2063 2064 mtx_unlock_spin(&ngq->q_mtx); 2065 NG_FREE_ITEM(item); 2066 mtx_lock_spin(&ngq->q_mtx); 2067 } 2068 /* 2069 * Take us off the work queue if we are there. 2070 * We definatly have no work to be done. 2071 */ 2072 ng_worklist_remove(ngq->q_node); 2073 mtx_unlock_spin(&ngq->q_mtx); 2074 } 2075 2076 /*********************************************************************** 2077 * Externally visible method for sending or queueing messages or data. 2078 ***********************************************************************/ 2079 2080 /* 2081 * The module code should have filled out the item correctly by this stage: 2082 * Common: 2083 * reference to destination node. 2084 * Reference to destination rcv hook if relevant. 2085 * Data: 2086 * pointer to mbuf 2087 * Control_Message: 2088 * pointer to msg. 2089 * ID of original sender node. (return address) 2090 * Function: 2091 * Function pointer 2092 * void * argument 2093 * integer argument 2094 * 2095 * The nodes have several routines and macros to help with this task: 2096 */ 2097 2098 int 2099 ng_snd_item(item_p item, int queue) 2100 { 2101 hook_p hook = NGI_HOOK(item); 2102 node_p node = NGI_NODE(item); 2103 int rw; 2104 int error = 0, ierror; 2105 item_p oitem; 2106 struct ng_queue * ngq = &node->nd_input_queue; 2107 2108 #ifdef NETGRAPH_DEBUG 2109 _ngi_check(item, __FILE__, __LINE__); 2110 #endif 2111 2112 if (item == NULL) { 2113 TRAP_ERROR(); 2114 return (EINVAL); /* failed to get queue element */ 2115 } 2116 if (node == NULL) { 2117 NG_FREE_ITEM(item); 2118 TRAP_ERROR(); 2119 return (EINVAL); /* No address */ 2120 } 2121 switch(item->el_flags & NGQF_TYPE) { 2122 case NGQF_DATA: 2123 /* 2124 * DATA MESSAGE 2125 * Delivered to a node via a non-optional hook. 2126 * Both should be present in the item even though 2127 * the node is derivable from the hook. 2128 * References are held on both by the item. 2129 */ 2130 2131 /* Protect nodes from sending NULL pointers 2132 * to each other 2133 */ 2134 if (NGI_M(item) == NULL) 2135 return (EINVAL); 2136 2137 CHECK_DATA_MBUF(NGI_M(item)); 2138 if (hook == NULL) { 2139 NG_FREE_ITEM(item); 2140 TRAP_ERROR(); 2141 return(EINVAL); 2142 } 2143 if ((NG_HOOK_NOT_VALID(hook)) 2144 || (NG_NODE_NOT_VALID(NG_HOOK_NODE(hook)))) { 2145 NG_FREE_ITEM(item); 2146 return (ENOTCONN); 2147 } 2148 if ((hook->hk_flags & HK_QUEUE)) { 2149 queue = 1; 2150 } 2151 /* By default data is a reader in the locking scheme */ 2152 item->el_flags |= NGQF_READER; 2153 rw = NGQRW_R; 2154 break; 2155 case NGQF_MESG: 2156 /* 2157 * CONTROL MESSAGE 2158 * Delivered to a node. 2159 * Hook is optional. 2160 * References are held by the item on the node and 2161 * the hook if it is present. 2162 */ 2163 if (hook && (hook->hk_flags & HK_QUEUE)) { 2164 queue = 1; 2165 } 2166 /* Data messages count as writers unles explicitly exempted */ 2167 if (NGI_MSG(item)->header.cmd & NGM_READONLY) { 2168 item->el_flags |= NGQF_READER; 2169 rw = NGQRW_R; 2170 } else { 2171 item->el_flags &= ~NGQF_RW; 2172 rw = NGQRW_W; 2173 } 2174 break; 2175 case NGQF_FN: 2176 item->el_flags &= ~NGQF_RW; 2177 rw = NGQRW_W; 2178 break; 2179 default: 2180 NG_FREE_ITEM(item); 2181 TRAP_ERROR(); 2182 return (EINVAL); 2183 } 2184 /* 2185 * If the node specifies single threading, force writer semantics 2186 * Similarly the node may say one hook always produces writers. 2187 * These are over-rides. 2188 */ 2189 if ((node->nd_flags & NGF_FORCE_WRITER) 2190 || (hook && (hook->hk_flags & HK_FORCE_WRITER))) { 2191 rw = NGQRW_W; 2192 item->el_flags &= ~NGQF_READER; 2193 } 2194 if (queue) { 2195 /* Put it on the queue for that node*/ 2196 #ifdef NETGRAPH_DEBUG 2197 _ngi_check(item, __FILE__, __LINE__); 2198 #endif 2199 mtx_lock_spin(&(ngq->q_mtx)); 2200 ng_queue_rw(ngq, item, rw); 2201 /* 2202 * If there are active elements then we can rely on 2203 * them. if not we should not rely on another packet 2204 * coming here by another path, 2205 * so it is best to put us in the netisr list. 2206 * We can take the worklist lock with the node locked 2207 * BUT NOT THE REVERSE! 2208 */ 2209 if (CAN_GET_WORK(ngq->q_flags)) { 2210 ng_setisr(node); 2211 } 2212 mtx_unlock_spin(&(ngq->q_mtx)); 2213 return (0); 2214 } 2215 /* 2216 * Take a queue item and a node and see if we can apply the item to 2217 * the node. We may end up getting a different item to apply instead. 2218 * Will allow for a piggyback reply only in the case where 2219 * there is no queueing. 2220 */ 2221 2222 oitem = item; 2223 /* 2224 * We already decided how we will be queueud or treated. 2225 * Try get the appropriate operating permission. 2226 */ 2227 if (rw == NGQRW_R) { 2228 item = ng_acquire_read(ngq, item); 2229 } else { 2230 item = ng_acquire_write(ngq, item); 2231 } 2232 2233 /* 2234 * May have come back with a different item. 2235 * or maybe none at all. The one we started with will 2236 * have been queued in thises cases. 2237 */ 2238 if (item == NULL) { 2239 return (0); 2240 } 2241 2242 #ifdef NETGRAPH_DEBUG 2243 _ngi_check(item, __FILE__, __LINE__); 2244 #endif 2245 /* 2246 * Take over the reference frm the item. 2247 * Hold it until the called function returns. 2248 */ 2249 NGI_GET_NODE(item, node); /* zaps stored node */ 2250 2251 ierror = ng_apply_item(node, item); /* drops r/w lock when done */ 2252 2253 /* only return an error if it was our initial item.. (compat hack) */ 2254 if (oitem == item) { 2255 error = ierror; 2256 } 2257 2258 /* 2259 * If the node goes away when we remove the reference, 2260 * whatever we just did caused it.. whatever we do, DO NOT 2261 * access the node again! 2262 */ 2263 if (NG_NODE_UNREF(node) == 0) { 2264 return (error); 2265 } 2266 2267 /* 2268 * Now we've handled the packet we brought, (or a friend of it) let's 2269 * look for any other packets that may have been queued up. We hold 2270 * no locks, so if someone puts something in the queue after 2271 * we check that it is empty, it is their problem 2272 * to ensure it is processed. If we have the netisr thread cme in here 2273 * while we still say we have stuff to do, we may get a boost 2274 * in SMP systems. :-) 2275 */ 2276 for (;;) { 2277 /* 2278 * dequeue acquires and adjusts the input_queue as it dequeues 2279 * packets. It acquires the rw lock as needed. 2280 */ 2281 mtx_lock_spin(&ngq->q_mtx); 2282 item = ng_dequeue(ngq); /* fixes worklist too*/ 2283 if (!item) { 2284 mtx_unlock_spin(&ngq->q_mtx); 2285 return (error); 2286 } 2287 mtx_unlock_spin(&ngq->q_mtx); 2288 2289 /* 2290 * Take over the reference frm the item. 2291 * Hold it until the called function returns. 2292 */ 2293 2294 NGI_GET_NODE(item, node); /* zaps stored node */ 2295 2296 /* 2297 * We have the appropriate lock, so run the item. 2298 * When finished it will drop the lock accordingly 2299 */ 2300 ierror = ng_apply_item(node, item); 2301 2302 /* 2303 * only return an error if it was our initial 2304 * item.. (compat hack) 2305 */ 2306 if (oitem == item) { 2307 error = ierror; 2308 } 2309 2310 /* 2311 * If the node goes away when we remove the reference, 2312 * whatever we just did caused it.. whatever we do, DO NOT 2313 * access the node again! 2314 */ 2315 if (NG_NODE_UNREF(node) == 0) { 2316 break; 2317 } 2318 } 2319 return (error); 2320 } 2321 2322 /* 2323 * We have an item that was possibly queued somewhere. 2324 * It should contain all the information needed 2325 * to run it on the appropriate node/hook. 2326 */ 2327 static int 2328 ng_apply_item(node_p node, item_p item) 2329 { 2330 hook_p hook; 2331 int was_reader = ((item->el_flags & NGQF_RW)); 2332 int error = 0; 2333 ng_rcvdata_t *rcvdata; 2334 ng_rcvmsg_t *rcvmsg; 2335 2336 NGI_GET_HOOK(item, hook); /* clears stored hook */ 2337 #ifdef NETGRAPH_DEBUG 2338 _ngi_check(item, __FILE__, __LINE__); 2339 #endif 2340 switch (item->el_flags & NGQF_TYPE) { 2341 case NGQF_DATA: 2342 /* 2343 * Check things are still ok as when we were queued. 2344 */ 2345 if ((hook == NULL) 2346 || NG_HOOK_NOT_VALID(hook) 2347 || NG_NODE_NOT_VALID(node) ) { 2348 error = EIO; 2349 NG_FREE_ITEM(item); 2350 break; 2351 } 2352 /* 2353 * If no receive method, just silently drop it. 2354 * Give preference to the hook over-ride method 2355 */ 2356 if ((!(rcvdata = hook->hk_rcvdata)) 2357 && (!(rcvdata = NG_HOOK_NODE(hook)->nd_type->rcvdata))) { 2358 error = 0; 2359 NG_FREE_ITEM(item); 2360 break; 2361 } 2362 error = (*rcvdata)(hook, item); 2363 break; 2364 case NGQF_MESG: 2365 if (hook) { 2366 if (NG_HOOK_NOT_VALID(hook)) { 2367 /* 2368 * The hook has been zapped then we can't 2369 * use it. Immediatly drop its reference. 2370 * The message may not need it. 2371 */ 2372 NG_HOOK_UNREF(hook); 2373 hook = NULL; 2374 } 2375 } 2376 /* 2377 * Similarly, if the node is a zombie there is 2378 * nothing we can do with it, drop everything. 2379 */ 2380 if (NG_NODE_NOT_VALID(node)) { 2381 TRAP_ERROR(); 2382 error = EINVAL; 2383 NG_FREE_ITEM(item); 2384 } else { 2385 /* 2386 * Call the appropriate message handler for the object. 2387 * It is up to the message handler to free the message. 2388 * If it's a generic message, handle it generically, 2389 * otherwise call the type's message handler 2390 * (if it exists) 2391 * XXX (race). Remember that a queued message may 2392 * reference a node or hook that has just been 2393 * invalidated. It will exist as the queue code 2394 * is holding a reference, but.. 2395 */ 2396 2397 struct ng_mesg *msg = NGI_MSG(item); 2398 2399 /* 2400 * check if the generic handler owns it. 2401 */ 2402 if ((msg->header.typecookie == NGM_GENERIC_COOKIE) 2403 && ((msg->header.flags & NGF_RESP) == 0)) { 2404 error = ng_generic_msg(node, item, hook); 2405 break; 2406 } 2407 /* 2408 * Now see if there is a handler (hook or node specific) 2409 * in the target node. If none, silently discard. 2410 */ 2411 if (((!hook) || (!(rcvmsg = hook->hk_rcvmsg))) 2412 && (!(rcvmsg = node->nd_type->rcvmsg))) { 2413 TRAP_ERROR(); 2414 error = 0; 2415 NG_FREE_ITEM(item); 2416 break; 2417 } 2418 error = (*rcvmsg)(node, item, hook); 2419 } 2420 break; 2421 case NGQF_FN: 2422 /* 2423 * We have to implicitly trust the hook, 2424 * as some of these are used for system purposes 2425 * where the hook is invalid. In the case of 2426 * the shutdown message we allow it to hit 2427 * even if the node is invalid. 2428 */ 2429 if ((NG_NODE_NOT_VALID(node)) 2430 && (NGI_FN(item) != &ng_rmnode)) { 2431 TRAP_ERROR(); 2432 error = EINVAL; 2433 break; 2434 } 2435 (*NGI_FN(item))(node, hook, NGI_ARG1(item), NGI_ARG2(item)); 2436 NG_FREE_ITEM(item); 2437 break; 2438 2439 } 2440 /* 2441 * We held references on some of the resources 2442 * that we took from the item. Now that we have 2443 * finished doing everything, drop those references. 2444 */ 2445 if (hook) { 2446 NG_HOOK_UNREF(hook); 2447 } 2448 2449 if (was_reader) { 2450 ng_leave_read(&node->nd_input_queue); 2451 } else { 2452 ng_leave_write(&node->nd_input_queue); 2453 } 2454 return (error); 2455 } 2456 2457 /*********************************************************************** 2458 * Implement the 'generic' control messages 2459 ***********************************************************************/ 2460 static int 2461 ng_generic_msg(node_p here, item_p item, hook_p lasthook) 2462 { 2463 int error = 0; 2464 struct ng_mesg *msg; 2465 struct ng_mesg *resp = NULL; 2466 2467 NGI_GET_MSG(item, msg); 2468 if (msg->header.typecookie != NGM_GENERIC_COOKIE) { 2469 TRAP_ERROR(); 2470 error = EINVAL; 2471 goto out; 2472 } 2473 switch (msg->header.cmd) { 2474 case NGM_SHUTDOWN: 2475 ng_rmnode(here, NULL, NULL, 0); 2476 break; 2477 case NGM_MKPEER: 2478 { 2479 struct ngm_mkpeer *const mkp = (struct ngm_mkpeer *) msg->data; 2480 2481 if (msg->header.arglen != sizeof(*mkp)) { 2482 TRAP_ERROR(); 2483 error = EINVAL; 2484 break; 2485 } 2486 mkp->type[sizeof(mkp->type) - 1] = '\0'; 2487 mkp->ourhook[sizeof(mkp->ourhook) - 1] = '\0'; 2488 mkp->peerhook[sizeof(mkp->peerhook) - 1] = '\0'; 2489 error = ng_mkpeer(here, mkp->ourhook, mkp->peerhook, mkp->type); 2490 break; 2491 } 2492 case NGM_CONNECT: 2493 { 2494 struct ngm_connect *const con = 2495 (struct ngm_connect *) msg->data; 2496 node_p node2; 2497 2498 if (msg->header.arglen != sizeof(*con)) { 2499 TRAP_ERROR(); 2500 error = EINVAL; 2501 break; 2502 } 2503 con->path[sizeof(con->path) - 1] = '\0'; 2504 con->ourhook[sizeof(con->ourhook) - 1] = '\0'; 2505 con->peerhook[sizeof(con->peerhook) - 1] = '\0'; 2506 /* Don't forget we get a reference.. */ 2507 error = ng_path2noderef(here, con->path, &node2, NULL); 2508 if (error) 2509 break; 2510 error = ng_con_nodes(here, con->ourhook, node2, con->peerhook); 2511 NG_NODE_UNREF(node2); 2512 break; 2513 } 2514 case NGM_NAME: 2515 { 2516 struct ngm_name *const nam = (struct ngm_name *) msg->data; 2517 2518 if (msg->header.arglen != sizeof(*nam)) { 2519 TRAP_ERROR(); 2520 error = EINVAL; 2521 break; 2522 } 2523 nam->name[sizeof(nam->name) - 1] = '\0'; 2524 error = ng_name_node(here, nam->name); 2525 break; 2526 } 2527 case NGM_RMHOOK: 2528 { 2529 struct ngm_rmhook *const rmh = (struct ngm_rmhook *) msg->data; 2530 hook_p hook; 2531 2532 if (msg->header.arglen != sizeof(*rmh)) { 2533 TRAP_ERROR(); 2534 error = EINVAL; 2535 break; 2536 } 2537 rmh->ourhook[sizeof(rmh->ourhook) - 1] = '\0'; 2538 if ((hook = ng_findhook(here, rmh->ourhook)) != NULL) 2539 ng_destroy_hook(hook); 2540 break; 2541 } 2542 case NGM_NODEINFO: 2543 { 2544 struct nodeinfo *ni; 2545 2546 NG_MKRESPONSE(resp, msg, sizeof(*ni), M_NOWAIT); 2547 if (resp == NULL) { 2548 error = ENOMEM; 2549 break; 2550 } 2551 2552 /* Fill in node info */ 2553 ni = (struct nodeinfo *) resp->data; 2554 if (NG_NODE_HAS_NAME(here)) 2555 strcpy(ni->name, NG_NODE_NAME(here)); 2556 strcpy(ni->type, here->nd_type->name); 2557 ni->id = ng_node2ID(here); 2558 ni->hooks = here->nd_numhooks; 2559 break; 2560 } 2561 case NGM_LISTHOOKS: 2562 { 2563 const int nhooks = here->nd_numhooks; 2564 struct hooklist *hl; 2565 struct nodeinfo *ni; 2566 hook_p hook; 2567 2568 /* Get response struct */ 2569 NG_MKRESPONSE(resp, msg, sizeof(*hl) 2570 + (nhooks * sizeof(struct linkinfo)), M_NOWAIT); 2571 if (resp == NULL) { 2572 error = ENOMEM; 2573 break; 2574 } 2575 hl = (struct hooklist *) resp->data; 2576 ni = &hl->nodeinfo; 2577 2578 /* Fill in node info */ 2579 if (NG_NODE_HAS_NAME(here)) 2580 strcpy(ni->name, NG_NODE_NAME(here)); 2581 strcpy(ni->type, here->nd_type->name); 2582 ni->id = ng_node2ID(here); 2583 2584 /* Cycle through the linked list of hooks */ 2585 ni->hooks = 0; 2586 LIST_FOREACH(hook, &here->nd_hooks, hk_hooks) { 2587 struct linkinfo *const link = &hl->link[ni->hooks]; 2588 2589 if (ni->hooks >= nhooks) { 2590 log(LOG_ERR, "%s: number of %s changed\n", 2591 __func__, "hooks"); 2592 break; 2593 } 2594 if (NG_HOOK_NOT_VALID(hook)) 2595 continue; 2596 strcpy(link->ourhook, NG_HOOK_NAME(hook)); 2597 strcpy(link->peerhook, NG_PEER_HOOK_NAME(hook)); 2598 if (NG_PEER_NODE_NAME(hook)[0] != '\0') 2599 strcpy(link->nodeinfo.name, 2600 NG_PEER_NODE_NAME(hook)); 2601 strcpy(link->nodeinfo.type, 2602 NG_PEER_NODE(hook)->nd_type->name); 2603 link->nodeinfo.id = ng_node2ID(NG_PEER_NODE(hook)); 2604 link->nodeinfo.hooks = NG_PEER_NODE(hook)->nd_numhooks; 2605 ni->hooks++; 2606 } 2607 break; 2608 } 2609 2610 case NGM_LISTNAMES: 2611 case NGM_LISTNODES: 2612 { 2613 const int unnamed = (msg->header.cmd == NGM_LISTNODES); 2614 struct namelist *nl; 2615 node_p node; 2616 int num = 0; 2617 2618 mtx_lock(&ng_nodelist_mtx); 2619 /* Count number of nodes */ 2620 LIST_FOREACH(node, &ng_nodelist, nd_nodes) { 2621 if (NG_NODE_IS_VALID(node) 2622 && (unnamed || NG_NODE_HAS_NAME(node))) { 2623 num++; 2624 } 2625 } 2626 mtx_unlock(&ng_nodelist_mtx); 2627 2628 /* Get response struct */ 2629 NG_MKRESPONSE(resp, msg, sizeof(*nl) 2630 + (num * sizeof(struct nodeinfo)), M_NOWAIT); 2631 if (resp == NULL) { 2632 error = ENOMEM; 2633 break; 2634 } 2635 nl = (struct namelist *) resp->data; 2636 2637 /* Cycle through the linked list of nodes */ 2638 nl->numnames = 0; 2639 mtx_lock(&ng_nodelist_mtx); 2640 LIST_FOREACH(node, &ng_nodelist, nd_nodes) { 2641 struct nodeinfo *const np = &nl->nodeinfo[nl->numnames]; 2642 2643 if (nl->numnames >= num) { 2644 log(LOG_ERR, "%s: number of %s changed\n", 2645 __func__, "nodes"); 2646 break; 2647 } 2648 if (NG_NODE_NOT_VALID(node)) 2649 continue; 2650 if (!unnamed && (! NG_NODE_HAS_NAME(node))) 2651 continue; 2652 if (NG_NODE_HAS_NAME(node)) 2653 strcpy(np->name, NG_NODE_NAME(node)); 2654 strcpy(np->type, node->nd_type->name); 2655 np->id = ng_node2ID(node); 2656 np->hooks = node->nd_numhooks; 2657 nl->numnames++; 2658 } 2659 mtx_unlock(&ng_nodelist_mtx); 2660 break; 2661 } 2662 2663 case NGM_LISTTYPES: 2664 { 2665 struct typelist *tl; 2666 struct ng_type *type; 2667 int num = 0; 2668 2669 mtx_lock(&ng_typelist_mtx); 2670 /* Count number of types */ 2671 LIST_FOREACH(type, &ng_typelist, types) { 2672 num++; 2673 } 2674 mtx_unlock(&ng_typelist_mtx); 2675 2676 /* Get response struct */ 2677 NG_MKRESPONSE(resp, msg, sizeof(*tl) 2678 + (num * sizeof(struct typeinfo)), M_NOWAIT); 2679 if (resp == NULL) { 2680 error = ENOMEM; 2681 break; 2682 } 2683 tl = (struct typelist *) resp->data; 2684 2685 /* Cycle through the linked list of types */ 2686 tl->numtypes = 0; 2687 mtx_lock(&ng_typelist_mtx); 2688 LIST_FOREACH(type, &ng_typelist, types) { 2689 struct typeinfo *const tp = &tl->typeinfo[tl->numtypes]; 2690 2691 if (tl->numtypes >= num) { 2692 log(LOG_ERR, "%s: number of %s changed\n", 2693 __func__, "types"); 2694 break; 2695 } 2696 strcpy(tp->type_name, type->name); 2697 tp->numnodes = type->refs - 1; /* don't count list */ 2698 tl->numtypes++; 2699 } 2700 mtx_unlock(&ng_typelist_mtx); 2701 break; 2702 } 2703 2704 case NGM_BINARY2ASCII: 2705 { 2706 int bufSize = 20 * 1024; /* XXX hard coded constant */ 2707 const struct ng_parse_type *argstype; 2708 const struct ng_cmdlist *c; 2709 struct ng_mesg *binary, *ascii; 2710 2711 /* Data area must contain a valid netgraph message */ 2712 binary = (struct ng_mesg *)msg->data; 2713 if (msg->header.arglen < sizeof(struct ng_mesg) 2714 || (msg->header.arglen - sizeof(struct ng_mesg) 2715 < binary->header.arglen)) { 2716 TRAP_ERROR(); 2717 error = EINVAL; 2718 break; 2719 } 2720 2721 /* Get a response message with lots of room */ 2722 NG_MKRESPONSE(resp, msg, sizeof(*ascii) + bufSize, M_NOWAIT); 2723 if (resp == NULL) { 2724 error = ENOMEM; 2725 break; 2726 } 2727 ascii = (struct ng_mesg *)resp->data; 2728 2729 /* Copy binary message header to response message payload */ 2730 bcopy(binary, ascii, sizeof(*binary)); 2731 2732 /* Find command by matching typecookie and command number */ 2733 for (c = here->nd_type->cmdlist; 2734 c != NULL && c->name != NULL; c++) { 2735 if (binary->header.typecookie == c->cookie 2736 && binary->header.cmd == c->cmd) 2737 break; 2738 } 2739 if (c == NULL || c->name == NULL) { 2740 for (c = ng_generic_cmds; c->name != NULL; c++) { 2741 if (binary->header.typecookie == c->cookie 2742 && binary->header.cmd == c->cmd) 2743 break; 2744 } 2745 if (c->name == NULL) { 2746 NG_FREE_MSG(resp); 2747 error = ENOSYS; 2748 break; 2749 } 2750 } 2751 2752 /* Convert command name to ASCII */ 2753 snprintf(ascii->header.cmdstr, sizeof(ascii->header.cmdstr), 2754 "%s", c->name); 2755 2756 /* Convert command arguments to ASCII */ 2757 argstype = (binary->header.flags & NGF_RESP) ? 2758 c->respType : c->mesgType; 2759 if (argstype == NULL) { 2760 *ascii->data = '\0'; 2761 } else { 2762 if ((error = ng_unparse(argstype, 2763 (u_char *)binary->data, 2764 ascii->data, bufSize)) != 0) { 2765 NG_FREE_MSG(resp); 2766 break; 2767 } 2768 } 2769 2770 /* Return the result as struct ng_mesg plus ASCII string */ 2771 bufSize = strlen(ascii->data) + 1; 2772 ascii->header.arglen = bufSize; 2773 resp->header.arglen = sizeof(*ascii) + bufSize; 2774 break; 2775 } 2776 2777 case NGM_ASCII2BINARY: 2778 { 2779 int bufSize = 2000; /* XXX hard coded constant */ 2780 const struct ng_cmdlist *c; 2781 const struct ng_parse_type *argstype; 2782 struct ng_mesg *ascii, *binary; 2783 int off = 0; 2784 2785 /* Data area must contain at least a struct ng_mesg + '\0' */ 2786 ascii = (struct ng_mesg *)msg->data; 2787 if ((msg->header.arglen < sizeof(*ascii) + 1) 2788 || (ascii->header.arglen < 1) 2789 || (msg->header.arglen 2790 < sizeof(*ascii) + ascii->header.arglen)) { 2791 TRAP_ERROR(); 2792 error = EINVAL; 2793 break; 2794 } 2795 ascii->data[ascii->header.arglen - 1] = '\0'; 2796 2797 /* Get a response message with lots of room */ 2798 NG_MKRESPONSE(resp, msg, sizeof(*binary) + bufSize, M_NOWAIT); 2799 if (resp == NULL) { 2800 error = ENOMEM; 2801 break; 2802 } 2803 binary = (struct ng_mesg *)resp->data; 2804 2805 /* Copy ASCII message header to response message payload */ 2806 bcopy(ascii, binary, sizeof(*ascii)); 2807 2808 /* Find command by matching ASCII command string */ 2809 for (c = here->nd_type->cmdlist; 2810 c != NULL && c->name != NULL; c++) { 2811 if (strcmp(ascii->header.cmdstr, c->name) == 0) 2812 break; 2813 } 2814 if (c == NULL || c->name == NULL) { 2815 for (c = ng_generic_cmds; c->name != NULL; c++) { 2816 if (strcmp(ascii->header.cmdstr, c->name) == 0) 2817 break; 2818 } 2819 if (c->name == NULL) { 2820 NG_FREE_MSG(resp); 2821 error = ENOSYS; 2822 break; 2823 } 2824 } 2825 2826 /* Convert command name to binary */ 2827 binary->header.cmd = c->cmd; 2828 binary->header.typecookie = c->cookie; 2829 2830 /* Convert command arguments to binary */ 2831 argstype = (binary->header.flags & NGF_RESP) ? 2832 c->respType : c->mesgType; 2833 if (argstype == NULL) { 2834 bufSize = 0; 2835 } else { 2836 if ((error = ng_parse(argstype, ascii->data, 2837 &off, (u_char *)binary->data, &bufSize)) != 0) { 2838 NG_FREE_MSG(resp); 2839 break; 2840 } 2841 } 2842 2843 /* Return the result */ 2844 binary->header.arglen = bufSize; 2845 resp->header.arglen = sizeof(*binary) + bufSize; 2846 break; 2847 } 2848 2849 case NGM_TEXT_CONFIG: 2850 case NGM_TEXT_STATUS: 2851 /* 2852 * This one is tricky as it passes the command down to the 2853 * actual node, even though it is a generic type command. 2854 * This means we must assume that the item/msg is already freed 2855 * when control passes back to us. 2856 */ 2857 if (here->nd_type->rcvmsg != NULL) { 2858 NGI_MSG(item) = msg; /* put it back as we found it */ 2859 return((*here->nd_type->rcvmsg)(here, item, lasthook)); 2860 } 2861 /* Fall through if rcvmsg not supported */ 2862 default: 2863 TRAP_ERROR(); 2864 error = EINVAL; 2865 } 2866 /* 2867 * Sometimes a generic message may be statically allocated 2868 * to avoid problems with allocating when in tight memeory situations. 2869 * Don't free it if it is so. 2870 * I break them appart here, because erros may cause a free if the item 2871 * in which case we'd be doing it twice. 2872 * they are kept together above, to simplify freeing. 2873 */ 2874 out: 2875 NG_RESPOND_MSG(error, here, item, resp); 2876 if (msg) 2877 NG_FREE_MSG(msg); 2878 return (error); 2879 } 2880 2881 /************************************************************************ 2882 Module routines 2883 ************************************************************************/ 2884 2885 /* 2886 * Handle the loading/unloading of a netgraph node type module 2887 */ 2888 int 2889 ng_mod_event(module_t mod, int event, void *data) 2890 { 2891 struct ng_type *const type = data; 2892 int s, error = 0; 2893 2894 switch (event) { 2895 case MOD_LOAD: 2896 2897 /* Register new netgraph node type */ 2898 s = splnet(); 2899 if ((error = ng_newtype(type)) != 0) { 2900 splx(s); 2901 break; 2902 } 2903 2904 /* Call type specific code */ 2905 if (type->mod_event != NULL) 2906 if ((error = (*type->mod_event)(mod, event, data))) { 2907 mtx_lock(&ng_typelist_mtx); 2908 type->refs--; /* undo it */ 2909 LIST_REMOVE(type, types); 2910 mtx_unlock(&ng_typelist_mtx); 2911 } 2912 splx(s); 2913 break; 2914 2915 case MOD_UNLOAD: 2916 s = splnet(); 2917 if (type->refs > 1) { /* make sure no nodes exist! */ 2918 error = EBUSY; 2919 } else { 2920 if (type->refs == 0) { 2921 /* failed load, nothing to undo */ 2922 splx(s); 2923 break; 2924 } 2925 if (type->mod_event != NULL) { /* check with type */ 2926 error = (*type->mod_event)(mod, event, data); 2927 if (error != 0) { /* type refuses.. */ 2928 splx(s); 2929 break; 2930 } 2931 } 2932 mtx_lock(&ng_typelist_mtx); 2933 LIST_REMOVE(type, types); 2934 mtx_unlock(&ng_typelist_mtx); 2935 } 2936 splx(s); 2937 break; 2938 2939 default: 2940 if (type->mod_event != NULL) 2941 error = (*type->mod_event)(mod, event, data); 2942 else 2943 error = EOPNOTSUPP; /* XXX ? */ 2944 break; 2945 } 2946 return (error); 2947 } 2948 2949 /* 2950 * Handle loading and unloading for this code. 2951 * The only thing we need to link into is the NETISR strucure. 2952 */ 2953 static int 2954 ngb_mod_event(module_t mod, int event, void *data) 2955 { 2956 int s, error = 0; 2957 2958 switch (event) { 2959 case MOD_LOAD: 2960 /* Register line discipline */ 2961 mtx_init(&ng_worklist_mtx, "ng_worklist", NULL, MTX_SPIN); 2962 mtx_init(&ng_typelist_mtx, "netgraph types mutex", NULL, 2963 MTX_DEF); 2964 mtx_init(&ng_nodelist_mtx, "netgraph nodelist mutex", NULL, 2965 MTX_DEF); 2966 mtx_init(&ng_idhash_mtx, "netgraph idhash mutex", NULL, 2967 MTX_DEF); 2968 mtx_init(&ngq_mtx, "netgraph free item list mutex", NULL, 2969 MTX_DEF); 2970 s = splimp(); 2971 /* XXX could use NETISR_MPSAFE but need to verify code */ 2972 netisr_register(NETISR_NETGRAPH, (netisr_t *)ngintr, NULL, 0); 2973 splx(s); 2974 break; 2975 case MOD_UNLOAD: 2976 /* You cant unload it because an interface may be using it. */ 2977 error = EBUSY; 2978 break; 2979 default: 2980 error = EOPNOTSUPP; 2981 break; 2982 } 2983 return (error); 2984 } 2985 2986 static moduledata_t netgraph_mod = { 2987 "netgraph", 2988 ngb_mod_event, 2989 (NULL) 2990 }; 2991 DECLARE_MODULE(netgraph, netgraph_mod, SI_SUB_DRIVERS, SI_ORDER_MIDDLE); 2992 SYSCTL_NODE(_net, OID_AUTO, graph, CTLFLAG_RW, 0, "netgraph Family"); 2993 SYSCTL_INT(_net_graph, OID_AUTO, abi_version, CTLFLAG_RD, 0, NG_ABI_VERSION,""); 2994 SYSCTL_INT(_net_graph, OID_AUTO, msg_version, CTLFLAG_RD, 0, NG_VERSION, ""); 2995 2996 /************************************************************************ 2997 Queue element get/free routines 2998 ************************************************************************/ 2999 3000 3001 static int allocated; /* number of items malloc'd */ 3002 3003 static int maxalloc = 128; /* limit the damage of a leak */ 3004 static int ngqfreemax = 64;/* cache at most this many */ 3005 3006 TUNABLE_INT("net.graph.maxalloc", &maxalloc); 3007 SYSCTL_INT(_net_graph, OID_AUTO, maxalloc, CTLFLAG_RDTUN, &maxalloc, 3008 0, "Maximum number of queue items to allocate"); 3009 3010 TUNABLE_INT("net.graph.ngqfreemax", &ngqfreemax); 3011 SYSCTL_INT(_net_graph, OID_AUTO, ngqfreemax, CTLFLAG_RDTUN, &ngqfreemax, 3012 0, "Maximum number of free queue items to cache"); 3013 3014 static const int ngqfreelow = 4; /* try malloc if free < this */ 3015 static volatile int ngqfreesize; /* number of cached entries */ 3016 static volatile item_p ngqfree; /* free ones */ 3017 3018 #ifdef NETGRAPH_DEBUG 3019 static TAILQ_HEAD(, ng_item) ng_itemlist = TAILQ_HEAD_INITIALIZER(ng_itemlist); 3020 #endif 3021 /* 3022 * Get a queue entry 3023 * This is usually called when a packet first enters netgraph. 3024 * By definition, this is usually from an interrupt, or from a user. 3025 * Users are not so important, but try be quick for the times that it's 3026 * an interrupt. 3027 * XXX If reserve is low, we should try to get 2 from malloc as this 3028 * would indicate it often fails. 3029 */ 3030 static item_p 3031 ng_getqblk(void) 3032 { 3033 item_p item = NULL; 3034 3035 /* 3036 * Try get a cached queue block, or else allocate a new one 3037 * If we are less than our reserve, try malloc. If malloc 3038 * fails, then that's what the reserve is for... 3039 * We have our little reserve 3040 * because we use M_NOWAIT for malloc. This just helps us 3041 * avoid dropping packets while not increasing the time 3042 * we take to service the interrupt (on average) (I hope). 3043 */ 3044 mtx_lock(&ngq_mtx); 3045 3046 if ((ngqfreesize < ngqfreelow) || (ngqfree == NULL)) { 3047 if (allocated < maxalloc) { /* don't leak forever */ 3048 MALLOC(item, item_p , 3049 sizeof(*item), M_NETGRAPH_ITEM, 3050 (M_NOWAIT | M_ZERO)); 3051 if (item) { 3052 #ifdef NETGRAPH_DEBUG 3053 TAILQ_INSERT_TAIL(&ng_itemlist, item, all); 3054 #endif /* NETGRAPH_DEBUG */ 3055 allocated++; 3056 } 3057 } 3058 } 3059 3060 /* 3061 * We didn't or couldn't malloc. 3062 * try get one from our cache. 3063 */ 3064 if (item == NULL && (item = ngqfree) != NULL) { 3065 ngqfree = item->el_next; 3066 ngqfreesize--; 3067 item->el_flags &= ~NGQF_FREE; 3068 } 3069 3070 mtx_unlock(&ngq_mtx); 3071 return (item); 3072 } 3073 3074 /* 3075 * Release a queue entry 3076 */ 3077 void 3078 ng_free_item(item_p item) 3079 { 3080 3081 /* 3082 * The item may hold resources on it's own. We need to free 3083 * these before we can free the item. What they are depends upon 3084 * what kind of item it is. it is important that nodes zero 3085 * out pointers to resources that they remove from the item 3086 * or we release them again here. 3087 */ 3088 if (item->el_flags & NGQF_FREE) { 3089 panic(" Freeing free queue item"); 3090 } 3091 switch (item->el_flags & NGQF_TYPE) { 3092 case NGQF_DATA: 3093 /* If we have an mbuf still attached.. */ 3094 NG_FREE_M(_NGI_M(item)); 3095 break; 3096 case NGQF_MESG: 3097 _NGI_RETADDR(item) = 0; 3098 NG_FREE_MSG(_NGI_MSG(item)); 3099 break; 3100 case NGQF_FN: 3101 /* nothing to free really, */ 3102 _NGI_FN(item) = NULL; 3103 _NGI_ARG1(item) = NULL; 3104 _NGI_ARG2(item) = 0; 3105 case NGQF_UNDEF: 3106 break; 3107 } 3108 /* If we still have a node or hook referenced... */ 3109 _NGI_CLR_NODE(item); 3110 _NGI_CLR_HOOK(item); 3111 item->el_flags |= NGQF_FREE; 3112 3113 mtx_lock(&ngq_mtx); 3114 if (ngqfreesize < ngqfreemax) { 3115 ngqfreesize++; 3116 item->el_next = ngqfree; 3117 ngqfree = item; 3118 } else { 3119 #ifdef NETGRAPH_DEBUG 3120 TAILQ_REMOVE(&ng_itemlist, item, all); 3121 #endif /* NETGRAPH_DEBUG */ 3122 NG_FREE_ITEM_REAL(item); 3123 allocated--; 3124 } 3125 mtx_unlock(&ngq_mtx); 3126 } 3127 3128 #ifdef NETGRAPH_DEBUG 3129 void 3130 dumphook (hook_p hook, char *file, int line) 3131 { 3132 printf("hook: name %s, %d refs, Last touched:\n", 3133 _NG_HOOK_NAME(hook), hook->hk_refs); 3134 printf(" Last active @ %s, line %d\n", 3135 hook->lastfile, hook->lastline); 3136 if (line) { 3137 printf(" problem discovered at file %s, line %d\n", file, line); 3138 } 3139 } 3140 3141 void 3142 dumpnode(node_p node, char *file, int line) 3143 { 3144 printf("node: ID [%x]: type '%s', %d hooks, flags 0x%x, %d refs, %s:\n", 3145 _NG_NODE_ID(node), node->nd_type->name, 3146 node->nd_numhooks, node->nd_flags, 3147 node->nd_refs, node->nd_name); 3148 printf(" Last active @ %s, line %d\n", 3149 node->lastfile, node->lastline); 3150 if (line) { 3151 printf(" problem discovered at file %s, line %d\n", file, line); 3152 } 3153 } 3154 3155 void 3156 dumpitem(item_p item, char *file, int line) 3157 { 3158 if (item->el_flags & NGQF_FREE) { 3159 printf(" Free item, freed at %s, line %d\n", 3160 item->lastfile, item->lastline); 3161 } else { 3162 printf(" ACTIVE item, last used at %s, line %d", 3163 item->lastfile, item->lastline); 3164 switch(item->el_flags & NGQF_TYPE) { 3165 case NGQF_DATA: 3166 printf(" - [data]\n"); 3167 break; 3168 case NGQF_MESG: 3169 printf(" - retaddr[%d]:\n", _NGI_RETADDR(item)); 3170 break; 3171 case NGQF_FN: 3172 printf(" - fn@%p (%p, %p, %p, %d (%x))\n", 3173 item->body.fn.fn_fn, 3174 NGI_NODE(item), 3175 NGI_HOOK(item), 3176 item->body.fn.fn_arg1, 3177 item->body.fn.fn_arg2, 3178 item->body.fn.fn_arg2); 3179 break; 3180 case NGQF_UNDEF: 3181 printf(" - UNDEFINED!\n"); 3182 } 3183 } 3184 if (line) { 3185 printf(" problem discovered at file %s, line %d\n", file, line); 3186 if (NGI_NODE(item)) { 3187 printf("node %p ([%x])\n", 3188 NGI_NODE(item), ng_node2ID(NGI_NODE(item))); 3189 } 3190 } 3191 } 3192 3193 static void 3194 ng_dumpitems(void) 3195 { 3196 item_p item; 3197 int i = 1; 3198 TAILQ_FOREACH(item, &ng_itemlist, all) { 3199 printf("[%d] ", i++); 3200 dumpitem(item, NULL, 0); 3201 } 3202 } 3203 3204 static void 3205 ng_dumpnodes(void) 3206 { 3207 node_p node; 3208 int i = 1; 3209 mtx_lock(&ng_nodelist_mtx); 3210 SLIST_FOREACH(node, &ng_allnodes, nd_all) { 3211 printf("[%d] ", i++); 3212 dumpnode(node, NULL, 0); 3213 } 3214 mtx_unlock(&ng_nodelist_mtx); 3215 } 3216 3217 static void 3218 ng_dumphooks(void) 3219 { 3220 hook_p hook; 3221 int i = 1; 3222 mtx_lock(&ng_nodelist_mtx); 3223 SLIST_FOREACH(hook, &ng_allhooks, hk_all) { 3224 printf("[%d] ", i++); 3225 dumphook(hook, NULL, 0); 3226 } 3227 mtx_unlock(&ng_nodelist_mtx); 3228 } 3229 3230 static int 3231 sysctl_debug_ng_dump_items(SYSCTL_HANDLER_ARGS) 3232 { 3233 int error; 3234 int val; 3235 int i; 3236 3237 val = allocated; 3238 i = 1; 3239 error = sysctl_handle_int(oidp, &val, sizeof(int), req); 3240 if (error != 0 || req->newptr == NULL) 3241 return (error); 3242 if (val == 42) { 3243 ng_dumpitems(); 3244 ng_dumpnodes(); 3245 ng_dumphooks(); 3246 } 3247 return (0); 3248 } 3249 3250 SYSCTL_PROC(_debug, OID_AUTO, ng_dump_items, CTLTYPE_INT | CTLFLAG_RW, 3251 0, sizeof(int), sysctl_debug_ng_dump_items, "I", "Number of allocated items"); 3252 #endif /* NETGRAPH_DEBUG */ 3253 3254 3255 /*********************************************************************** 3256 * Worklist routines 3257 **********************************************************************/ 3258 /* NETISR thread enters here */ 3259 /* 3260 * Pick a node off the list of nodes with work, 3261 * try get an item to process off it. 3262 * If there are no more, remove the node from the list. 3263 */ 3264 static void 3265 ngintr(void) 3266 { 3267 item_p item; 3268 node_p node = NULL; 3269 3270 for (;;) { 3271 mtx_lock_spin(&ng_worklist_mtx); 3272 node = TAILQ_FIRST(&ng_worklist); 3273 if (!node) { 3274 mtx_unlock_spin(&ng_worklist_mtx); 3275 break; 3276 } 3277 node->nd_flags &= ~NGF_WORKQ; 3278 TAILQ_REMOVE(&ng_worklist, node, nd_work); 3279 mtx_unlock_spin(&ng_worklist_mtx); 3280 /* 3281 * We have the node. We also take over the reference 3282 * that the list had on it. 3283 * Now process as much as you can, until it won't 3284 * let you have another item off the queue. 3285 * All this time, keep the reference 3286 * that lets us be sure that the node still exists. 3287 * Let the reference go at the last minute. 3288 * ng_dequeue will put us back on the worklist 3289 * if there is more too do. This may be of use if there 3290 * are Multiple Processors and multiple Net threads in the 3291 * future. 3292 */ 3293 for (;;) { 3294 mtx_lock_spin(&node->nd_input_queue.q_mtx); 3295 item = ng_dequeue(&node->nd_input_queue); 3296 if (item == NULL) { 3297 mtx_unlock_spin(&node->nd_input_queue.q_mtx); 3298 break; /* go look for another node */ 3299 } else { 3300 mtx_unlock_spin(&node->nd_input_queue.q_mtx); 3301 NGI_GET_NODE(item, node); /* zaps stored node */ 3302 ng_apply_item(node, item); 3303 NG_NODE_UNREF(node); 3304 } 3305 } 3306 NG_NODE_UNREF(node); 3307 } 3308 } 3309 3310 static void 3311 ng_worklist_remove(node_p node) 3312 { 3313 mtx_lock_spin(&ng_worklist_mtx); 3314 if (node->nd_flags & NGF_WORKQ) { 3315 node->nd_flags &= ~NGF_WORKQ; 3316 TAILQ_REMOVE(&ng_worklist, node, nd_work); 3317 mtx_unlock_spin(&ng_worklist_mtx); 3318 NG_NODE_UNREF(node); 3319 } else { 3320 mtx_unlock_spin(&ng_worklist_mtx); 3321 } 3322 } 3323 3324 /* 3325 * XXX 3326 * It's posible that a debugging NG_NODE_REF may need 3327 * to be outside the mutex zone 3328 */ 3329 static void 3330 ng_setisr(node_p node) 3331 { 3332 mtx_lock_spin(&ng_worklist_mtx); 3333 if ((node->nd_flags & NGF_WORKQ) == 0) { 3334 /* 3335 * If we are not already on the work queue, 3336 * then put us on. 3337 */ 3338 node->nd_flags |= NGF_WORKQ; 3339 TAILQ_INSERT_TAIL(&ng_worklist, node, nd_work); 3340 NG_NODE_REF(node); /* XXX fafe in mutex? */ 3341 } 3342 mtx_unlock_spin(&ng_worklist_mtx); 3343 schednetisr(NETISR_NETGRAPH); 3344 } 3345 3346 3347 /*********************************************************************** 3348 * Externally useable functions to set up a queue item ready for sending 3349 ***********************************************************************/ 3350 3351 #ifdef NETGRAPH_DEBUG 3352 #define ITEM_DEBUG_CHECKS \ 3353 do { \ 3354 if (NGI_NODE(item) ) { \ 3355 printf("item already has node"); \ 3356 kdb_enter("has node"); \ 3357 NGI_CLR_NODE(item); \ 3358 } \ 3359 if (NGI_HOOK(item) ) { \ 3360 printf("item already has hook"); \ 3361 kdb_enter("has hook"); \ 3362 NGI_CLR_HOOK(item); \ 3363 } \ 3364 } while (0) 3365 #else 3366 #define ITEM_DEBUG_CHECKS 3367 #endif 3368 3369 /* 3370 * Put mbuf into the item. 3371 * Hook and node references will be removed when the item is dequeued. 3372 * (or equivalent) 3373 * (XXX) Unsafe because no reference held by peer on remote node. 3374 * remote node might go away in this timescale. 3375 * We know the hooks can't go away because that would require getting 3376 * a writer item on both nodes and we must have at least a reader 3377 * here to eb able to do this. 3378 * Note that the hook loaded is the REMOTE hook. 3379 * 3380 * This is possibly in the critical path for new data. 3381 */ 3382 item_p 3383 ng_package_data(struct mbuf *m, void *dummy) 3384 { 3385 item_p item; 3386 3387 if ((item = ng_getqblk()) == NULL) { 3388 NG_FREE_M(m); 3389 return (NULL); 3390 } 3391 ITEM_DEBUG_CHECKS; 3392 item->el_flags = NGQF_DATA; 3393 item->el_next = NULL; 3394 NGI_M(item) = m; 3395 return (item); 3396 } 3397 3398 /* 3399 * Allocate a queue item and put items into it.. 3400 * Evaluate the address as this will be needed to queue it and 3401 * to work out what some of the fields should be. 3402 * Hook and node references will be removed when the item is dequeued. 3403 * (or equivalent) 3404 */ 3405 item_p 3406 ng_package_msg(struct ng_mesg *msg) 3407 { 3408 item_p item; 3409 3410 if ((item = ng_getqblk()) == NULL) { 3411 NG_FREE_MSG(msg); 3412 return (NULL); 3413 } 3414 ITEM_DEBUG_CHECKS; 3415 item->el_flags = NGQF_MESG; 3416 item->el_next = NULL; 3417 /* 3418 * Set the current lasthook into the queue item 3419 */ 3420 NGI_MSG(item) = msg; 3421 NGI_RETADDR(item) = 0; 3422 return (item); 3423 } 3424 3425 3426 3427 #define SET_RETADDR(item, here, retaddr) \ 3428 do { /* Data or fn items don't have retaddrs */ \ 3429 if ((item->el_flags & NGQF_TYPE) == NGQF_MESG) { \ 3430 if (retaddr) { \ 3431 NGI_RETADDR(item) = retaddr; \ 3432 } else { \ 3433 /* \ 3434 * The old return address should be ok. \ 3435 * If there isn't one, use the address \ 3436 * here. \ 3437 */ \ 3438 if (NGI_RETADDR(item) == 0) { \ 3439 NGI_RETADDR(item) \ 3440 = ng_node2ID(here); \ 3441 } \ 3442 } \ 3443 } \ 3444 } while (0) 3445 3446 int 3447 ng_address_hook(node_p here, item_p item, hook_p hook, ng_ID_t retaddr) 3448 { 3449 hook_p peer; 3450 node_p peernode; 3451 ITEM_DEBUG_CHECKS; 3452 /* 3453 * Quick sanity check.. 3454 * Since a hook holds a reference on it's node, once we know 3455 * that the peer is still connected (even if invalid,) we know 3456 * that the peer node is present, though maybe invalid. 3457 */ 3458 if ((hook == NULL) 3459 || NG_HOOK_NOT_VALID(hook) 3460 || (NG_HOOK_PEER(hook) == NULL) 3461 || NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook)) 3462 || NG_NODE_NOT_VALID(NG_PEER_NODE(hook))) { 3463 NG_FREE_ITEM(item); 3464 TRAP_ERROR(); 3465 return (ENETDOWN); 3466 } 3467 3468 /* 3469 * Transfer our interest to the other (peer) end. 3470 */ 3471 peer = NG_HOOK_PEER(hook); 3472 NG_HOOK_REF(peer); 3473 NGI_SET_HOOK(item, peer); 3474 peernode = NG_PEER_NODE(hook); 3475 NG_NODE_REF(peernode); 3476 NGI_SET_NODE(item, peernode); 3477 SET_RETADDR(item, here, retaddr); 3478 return (0); 3479 } 3480 3481 int 3482 ng_address_path(node_p here, item_p item, char *address, ng_ID_t retaddr) 3483 { 3484 node_p dest = NULL; 3485 hook_p hook = NULL; 3486 int error; 3487 3488 ITEM_DEBUG_CHECKS; 3489 /* 3490 * Note that ng_path2noderef increments the reference count 3491 * on the node for us if it finds one. So we don't have to. 3492 */ 3493 error = ng_path2noderef(here, address, &dest, &hook); 3494 if (error) { 3495 NG_FREE_ITEM(item); 3496 return (error); 3497 } 3498 NGI_SET_NODE(item, dest); 3499 if ( hook) { 3500 NG_HOOK_REF(hook); /* don't let it go while on the queue */ 3501 NGI_SET_HOOK(item, hook); 3502 } 3503 SET_RETADDR(item, here, retaddr); 3504 return (0); 3505 } 3506 3507 int 3508 ng_address_ID(node_p here, item_p item, ng_ID_t ID, ng_ID_t retaddr) 3509 { 3510 node_p dest; 3511 3512 ITEM_DEBUG_CHECKS; 3513 /* 3514 * Find the target node. 3515 */ 3516 dest = ng_ID2noderef(ID); /* GETS REFERENCE! */ 3517 if (dest == NULL) { 3518 NG_FREE_ITEM(item); 3519 TRAP_ERROR(); 3520 return(EINVAL); 3521 } 3522 /* Fill out the contents */ 3523 item->el_flags = NGQF_MESG; 3524 item->el_next = NULL; 3525 NGI_SET_NODE(item, dest); 3526 NGI_CLR_HOOK(item); 3527 SET_RETADDR(item, here, retaddr); 3528 return (0); 3529 } 3530 3531 /* 3532 * special case to send a message to self (e.g. destroy node) 3533 * Possibly indicate an arrival hook too. 3534 * Useful for removing that hook :-) 3535 */ 3536 item_p 3537 ng_package_msg_self(node_p here, hook_p hook, struct ng_mesg *msg) 3538 { 3539 item_p item; 3540 3541 /* 3542 * Find the target node. 3543 * If there is a HOOK argument, then use that in preference 3544 * to the address. 3545 */ 3546 if ((item = ng_getqblk()) == NULL) { 3547 NG_FREE_MSG(msg); 3548 return (NULL); 3549 } 3550 3551 /* Fill out the contents */ 3552 item->el_flags = NGQF_MESG; 3553 item->el_next = NULL; 3554 NG_NODE_REF(here); 3555 NGI_SET_NODE(item, here); 3556 if (hook) { 3557 NG_HOOK_REF(hook); 3558 NGI_SET_HOOK(item, hook); 3559 } 3560 NGI_MSG(item) = msg; 3561 NGI_RETADDR(item) = ng_node2ID(here); 3562 return (item); 3563 } 3564 3565 int 3566 ng_send_fn(node_p node, hook_p hook, ng_item_fn *fn, void * arg1, int arg2) 3567 { 3568 item_p item; 3569 3570 if ((item = ng_getqblk()) == NULL) { 3571 return (ENOMEM); 3572 } 3573 item->el_flags = NGQF_FN | NGQF_WRITER; 3574 NG_NODE_REF(node); /* and one for the item */ 3575 NGI_SET_NODE(item, node); 3576 if (hook) { 3577 NG_HOOK_REF(hook); 3578 NGI_SET_HOOK(item, hook); 3579 } 3580 NGI_FN(item) = fn; 3581 NGI_ARG1(item) = arg1; 3582 NGI_ARG2(item) = arg2; 3583 return(ng_snd_item(item, 0)); 3584 } 3585 3586 /* 3587 * Official timeout routines for Netgraph nodes. 3588 */ 3589 static void 3590 ng_timeout_trapoline(void *arg) 3591 { 3592 item_p item = arg; 3593 3594 ng_snd_item(item, 0); 3595 } 3596 3597 3598 struct callout_handle 3599 ng_timeout(node_p node, hook_p hook, int ticks, 3600 ng_item_fn *fn, void * arg1, int arg2) 3601 { 3602 item_p item; 3603 3604 if ((item = ng_getqblk()) == NULL) { 3605 struct callout_handle handle; 3606 handle.callout = NULL; 3607 return (handle); 3608 } 3609 item->el_flags = NGQF_FN | NGQF_WRITER; 3610 NG_NODE_REF(node); /* and one for the item */ 3611 NGI_SET_NODE(item, node); 3612 if (hook) { 3613 NG_HOOK_REF(hook); 3614 NGI_SET_HOOK(item, hook); 3615 } 3616 NGI_FN(item) = fn; 3617 NGI_ARG1(item) = arg1; 3618 NGI_ARG2(item) = arg2; 3619 return (timeout(&ng_timeout_trapoline, item, ticks)); 3620 } 3621 3622 /* A special modified version of untimeout() */ 3623 int 3624 ng_untimeout(struct callout_handle handle, node_p node) 3625 { 3626 item_p item; 3627 3628 if (handle.callout == NULL) 3629 return (0); 3630 mtx_lock_spin(&callout_lock); 3631 item = handle.callout->c_arg; /* should be an official way to do this */ 3632 if ((handle.callout->c_func == &ng_timeout_trapoline) && 3633 (NGI_NODE(item) == node) && 3634 (callout_stop(handle.callout))) { 3635 /* 3636 * We successfully removed it from the queue before it ran 3637 * So now we need to unreference everything that was 3638 * given extra references. (NG_FREE_ITEM does this). 3639 */ 3640 mtx_unlock_spin(&callout_lock); 3641 NG_FREE_ITEM(item); 3642 return (1); 3643 } 3644 mtx_unlock_spin(&callout_lock); 3645 return (0); 3646 } 3647 3648 /* 3649 * Set the address, if none given, give the node here. 3650 */ 3651 void 3652 ng_replace_retaddr(node_p here, item_p item, ng_ID_t retaddr) 3653 { 3654 if (retaddr) { 3655 NGI_RETADDR(item) = retaddr; 3656 } else { 3657 /* 3658 * The old return address should be ok. 3659 * If there isn't one, use the address here. 3660 */ 3661 NGI_RETADDR(item) = ng_node2ID(here); 3662 } 3663 } 3664 3665 #define TESTING 3666 #ifdef TESTING 3667 /* just test all the macros */ 3668 void 3669 ng_macro_test(item_p item); 3670 void 3671 ng_macro_test(item_p item) 3672 { 3673 node_p node = NULL; 3674 hook_p hook = NULL; 3675 struct mbuf *m; 3676 struct ng_mesg *msg; 3677 ng_ID_t retaddr; 3678 int error; 3679 3680 NGI_GET_M(item, m); 3681 NGI_GET_MSG(item, msg); 3682 retaddr = NGI_RETADDR(item); 3683 NG_SEND_DATA(error, hook, m, NULL); 3684 NG_SEND_DATA_ONLY(error, hook, m); 3685 NG_FWD_NEW_DATA(error, item, hook, m); 3686 NG_FWD_ITEM_HOOK(error, item, hook); 3687 NG_SEND_MSG_HOOK(error, node, msg, hook, retaddr); 3688 NG_SEND_MSG_ID(error, node, msg, retaddr, retaddr); 3689 NG_SEND_MSG_PATH(error, node, msg, ".:", retaddr); 3690 NG_FWD_MSG_HOOK(error, node, item, hook, retaddr); 3691 } 3692 #endif /* TESTING */ 3693 3694