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/kernel.h> 51 #include <sys/limits.h> 52 #include <sys/malloc.h> 53 #include <sys/syslog.h> 54 #include <sys/sysctl.h> 55 #include <sys/linker.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 NG_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 LIST_FOREACH(node, &ng_ID_hash[NG_IDHASH_FN(ID)], \ 174 nd_idnodes) { \ 175 if (NG_NODE_IS_VALID(node) \ 176 && (NG_NODE_ID(node) == ID)) { \ 177 break; \ 178 } \ 179 } \ 180 } while (0) 181 182 183 /* Internal functions */ 184 static int ng_add_hook(node_p node, const char *name, hook_p * hookp); 185 static int ng_generic_msg(node_p here, item_p item, hook_p lasthook); 186 static ng_ID_t ng_decodeidname(const char *name); 187 static int ngb_mod_event(module_t mod, int event, void *data); 188 static void ng_worklist_remove(node_p node); 189 static void ngintr(void); 190 static int ng_apply_item(node_p node, item_p item); 191 static void ng_flush_input_queue(struct ng_queue * ngq); 192 static void ng_setisr(node_p node); 193 static node_p ng_ID2noderef(ng_ID_t ID); 194 static int ng_con_nodes(node_p node, const char *name, node_p node2, 195 const char *name2); 196 static void ng_con_part2(node_p node, hook_p hook, void *arg1, int arg2); 197 static void ng_con_part3(node_p node, hook_p hook, void *arg1, int arg2); 198 static int ng_mkpeer(node_p node, const char *name, 199 const char *name2, char *type); 200 201 /* imported , these used to be externally visible, some may go back */ 202 int ng_bypass(hook_p hook1, hook_p hook2); 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 struct ng_type *ng_findtype(const char *type); 208 int ng_make_node(const char *type, node_p *nodepp); 209 int ng_path_parse(char *addr, char **node, char **path, char **hook); 210 void ng_rmnode(node_p node, hook_p dummy1, void *dummy2, int dummy3); 211 void ng_unname(node_p node); 212 213 214 /* Our own netgraph malloc type */ 215 MALLOC_DEFINE(M_NETGRAPH, "netgraph", "netgraph structures and ctrl messages"); 216 MALLOC_DEFINE(M_NETGRAPH_HOOK, "netgraph_hook", "netgraph hook structures"); 217 MALLOC_DEFINE(M_NETGRAPH_NODE, "netgraph_node", "netgraph node structures"); 218 MALLOC_DEFINE(M_NETGRAPH_ITEM, "netgraph_item", "netgraph item structures"); 219 MALLOC_DEFINE(M_NETGRAPH_META, "netgraph_meta", "netgraph name storage"); 220 MALLOC_DEFINE(M_NETGRAPH_MSG, "netgraph_msg", "netgraph name storage"); 221 222 /* Should not be visible outside this file */ 223 224 #define _NG_ALLOC_HOOK(hook) \ 225 MALLOC(hook, hook_p, sizeof(*hook), M_NETGRAPH_HOOK, M_NOWAIT | M_ZERO) 226 #define _NG_ALLOC_NODE(node) \ 227 MALLOC(node, node_p, sizeof(*node), M_NETGRAPH_NODE, M_NOWAIT | M_ZERO) 228 229 #ifdef NETGRAPH_DEBUG /*----------------------------------------------*/ 230 /* 231 * In debug mode: 232 * In an attempt to help track reference count screwups 233 * we do not free objects back to the malloc system, but keep them 234 * in a local cache where we can examine them and keep information safely 235 * after they have been freed. 236 * We use this scheme for nodes and hooks, and to some extent for items. 237 */ 238 static __inline hook_p 239 ng_alloc_hook(void) 240 { 241 hook_p hook; 242 SLIST_ENTRY(ng_hook) temp; 243 mtx_lock(&ng_nodelist_mtx); 244 hook = LIST_FIRST(&ng_freehooks); 245 if (hook) { 246 LIST_REMOVE(hook, hk_hooks); 247 bcopy(&hook->hk_all, &temp, sizeof(temp)); 248 bzero(hook, sizeof(struct ng_hook)); 249 bcopy(&temp, &hook->hk_all, sizeof(temp)); 250 mtx_unlock(&ng_nodelist_mtx); 251 hook->hk_magic = HK_MAGIC; 252 } else { 253 mtx_unlock(&ng_nodelist_mtx); 254 _NG_ALLOC_HOOK(hook); 255 if (hook) { 256 hook->hk_magic = HK_MAGIC; 257 mtx_lock(&ng_nodelist_mtx); 258 SLIST_INSERT_HEAD(&ng_allhooks, hook, hk_all); 259 mtx_unlock(&ng_nodelist_mtx); 260 } 261 } 262 return (hook); 263 } 264 265 static __inline node_p 266 ng_alloc_node(void) 267 { 268 node_p node; 269 SLIST_ENTRY(ng_node) temp; 270 mtx_lock(&ng_nodelist_mtx); 271 node = LIST_FIRST(&ng_freenodes); 272 if (node) { 273 LIST_REMOVE(node, nd_nodes); 274 bcopy(&node->nd_all, &temp, sizeof(temp)); 275 bzero(node, sizeof(struct ng_node)); 276 bcopy(&temp, &node->nd_all, sizeof(temp)); 277 mtx_unlock(&ng_nodelist_mtx); 278 node->nd_magic = ND_MAGIC; 279 } else { 280 mtx_unlock(&ng_nodelist_mtx); 281 _NG_ALLOC_NODE(node); 282 if (node) { 283 node->nd_magic = ND_MAGIC; 284 mtx_lock(&ng_nodelist_mtx); 285 SLIST_INSERT_HEAD(&ng_allnodes, node, nd_all); 286 mtx_unlock(&ng_nodelist_mtx); 287 } 288 } 289 return (node); 290 } 291 292 #define NG_ALLOC_HOOK(hook) do { (hook) = ng_alloc_hook(); } while (0) 293 #define NG_ALLOC_NODE(node) do { (node) = ng_alloc_node(); } while (0) 294 295 296 #define NG_FREE_HOOK(hook) \ 297 do { \ 298 mtx_lock(&ng_nodelist_mtx); \ 299 LIST_INSERT_HEAD(&ng_freehooks, hook, hk_hooks); \ 300 hook->hk_magic = 0; \ 301 mtx_unlock(&ng_nodelist_mtx); \ 302 } while (0) 303 304 #define NG_FREE_NODE(node) \ 305 do { \ 306 mtx_lock(&ng_nodelist_mtx); \ 307 LIST_INSERT_HEAD(&ng_freenodes, node, nd_nodes); \ 308 node->nd_magic = 0; \ 309 mtx_unlock(&ng_nodelist_mtx); \ 310 } while (0) 311 312 #else /* NETGRAPH_DEBUG */ /*----------------------------------------------*/ 313 314 #define NG_ALLOC_HOOK(hook) _NG_ALLOC_HOOK(hook) 315 #define NG_ALLOC_NODE(node) _NG_ALLOC_NODE(node) 316 317 #define NG_FREE_HOOK(hook) do { FREE((hook), M_NETGRAPH_HOOK); } while (0) 318 #define NG_FREE_NODE(node) do { FREE((node), M_NETGRAPH_NODE); } while (0) 319 320 #endif /* NETGRAPH_DEBUG */ /*----------------------------------------------*/ 321 322 /* Warning: Generally use NG_FREE_ITEM() instead */ 323 #define NG_FREE_ITEM_REAL(item) do { FREE((item), M_NETGRAPH_ITEM); } while (0) 324 325 326 /* Set this to Debugger("X") to catch all errors as they occur */ 327 #ifndef TRAP_ERROR 328 #define TRAP_ERROR() 329 #endif 330 331 static ng_ID_t nextID = 1; 332 333 #ifdef INVARIANTS 334 #define CHECK_DATA_MBUF(m) do { \ 335 struct mbuf *n; \ 336 int total; \ 337 \ 338 M_ASSERTPKTHDR(m); \ 339 for (total = 0, n = (m); n != NULL; n = n->m_next) \ 340 total += n->m_len; \ 341 if ((m)->m_pkthdr.len != total) { \ 342 panic("%s: %d != %d", \ 343 __func__, (m)->m_pkthdr.len, total); \ 344 } \ 345 } while (0) 346 #else 347 #define CHECK_DATA_MBUF(m) 348 #endif 349 350 351 /************************************************************************ 352 Parse type definitions for generic messages 353 ************************************************************************/ 354 355 /* Handy structure parse type defining macro */ 356 #define DEFINE_PARSE_STRUCT_TYPE(lo, up, args) \ 357 static const struct ng_parse_struct_field \ 358 ng_ ## lo ## _type_fields[] = NG_GENERIC_ ## up ## _INFO args; \ 359 static const struct ng_parse_type ng_generic_ ## lo ## _type = { \ 360 &ng_parse_struct_type, \ 361 &ng_ ## lo ## _type_fields \ 362 } 363 364 DEFINE_PARSE_STRUCT_TYPE(mkpeer, MKPEER, ()); 365 DEFINE_PARSE_STRUCT_TYPE(connect, CONNECT, ()); 366 DEFINE_PARSE_STRUCT_TYPE(name, NAME, ()); 367 DEFINE_PARSE_STRUCT_TYPE(rmhook, RMHOOK, ()); 368 DEFINE_PARSE_STRUCT_TYPE(nodeinfo, NODEINFO, ()); 369 DEFINE_PARSE_STRUCT_TYPE(typeinfo, TYPEINFO, ()); 370 DEFINE_PARSE_STRUCT_TYPE(linkinfo, LINKINFO, (&ng_generic_nodeinfo_type)); 371 372 /* Get length of an array when the length is stored as a 32 bit 373 value immediately preceding the array -- as with struct namelist 374 and struct typelist. */ 375 static int 376 ng_generic_list_getLength(const struct ng_parse_type *type, 377 const u_char *start, const u_char *buf) 378 { 379 return *((const u_int32_t *)(buf - 4)); 380 } 381 382 /* Get length of the array of struct linkinfo inside a struct hooklist */ 383 static int 384 ng_generic_linkinfo_getLength(const struct ng_parse_type *type, 385 const u_char *start, const u_char *buf) 386 { 387 const struct hooklist *hl = (const struct hooklist *)start; 388 389 return hl->nodeinfo.hooks; 390 } 391 392 /* Array type for a variable length array of struct namelist */ 393 static const struct ng_parse_array_info ng_nodeinfoarray_type_info = { 394 &ng_generic_nodeinfo_type, 395 &ng_generic_list_getLength 396 }; 397 static const struct ng_parse_type ng_generic_nodeinfoarray_type = { 398 &ng_parse_array_type, 399 &ng_nodeinfoarray_type_info 400 }; 401 402 /* Array type for a variable length array of struct typelist */ 403 static const struct ng_parse_array_info ng_typeinfoarray_type_info = { 404 &ng_generic_typeinfo_type, 405 &ng_generic_list_getLength 406 }; 407 static const struct ng_parse_type ng_generic_typeinfoarray_type = { 408 &ng_parse_array_type, 409 &ng_typeinfoarray_type_info 410 }; 411 412 /* Array type for array of struct linkinfo in struct hooklist */ 413 static const struct ng_parse_array_info ng_generic_linkinfo_array_type_info = { 414 &ng_generic_linkinfo_type, 415 &ng_generic_linkinfo_getLength 416 }; 417 static const struct ng_parse_type ng_generic_linkinfo_array_type = { 418 &ng_parse_array_type, 419 &ng_generic_linkinfo_array_type_info 420 }; 421 422 DEFINE_PARSE_STRUCT_TYPE(typelist, TYPELIST, (&ng_generic_nodeinfoarray_type)); 423 DEFINE_PARSE_STRUCT_TYPE(hooklist, HOOKLIST, 424 (&ng_generic_nodeinfo_type, &ng_generic_linkinfo_array_type)); 425 DEFINE_PARSE_STRUCT_TYPE(listnodes, LISTNODES, 426 (&ng_generic_nodeinfoarray_type)); 427 428 /* List of commands and how to convert arguments to/from ASCII */ 429 static const struct ng_cmdlist ng_generic_cmds[] = { 430 { 431 NGM_GENERIC_COOKIE, 432 NGM_SHUTDOWN, 433 "shutdown", 434 NULL, 435 NULL 436 }, 437 { 438 NGM_GENERIC_COOKIE, 439 NGM_MKPEER, 440 "mkpeer", 441 &ng_generic_mkpeer_type, 442 NULL 443 }, 444 { 445 NGM_GENERIC_COOKIE, 446 NGM_CONNECT, 447 "connect", 448 &ng_generic_connect_type, 449 NULL 450 }, 451 { 452 NGM_GENERIC_COOKIE, 453 NGM_NAME, 454 "name", 455 &ng_generic_name_type, 456 NULL 457 }, 458 { 459 NGM_GENERIC_COOKIE, 460 NGM_RMHOOK, 461 "rmhook", 462 &ng_generic_rmhook_type, 463 NULL 464 }, 465 { 466 NGM_GENERIC_COOKIE, 467 NGM_NODEINFO, 468 "nodeinfo", 469 NULL, 470 &ng_generic_nodeinfo_type 471 }, 472 { 473 NGM_GENERIC_COOKIE, 474 NGM_LISTHOOKS, 475 "listhooks", 476 NULL, 477 &ng_generic_hooklist_type 478 }, 479 { 480 NGM_GENERIC_COOKIE, 481 NGM_LISTNAMES, 482 "listnames", 483 NULL, 484 &ng_generic_listnodes_type /* same as NGM_LISTNODES */ 485 }, 486 { 487 NGM_GENERIC_COOKIE, 488 NGM_LISTNODES, 489 "listnodes", 490 NULL, 491 &ng_generic_listnodes_type 492 }, 493 { 494 NGM_GENERIC_COOKIE, 495 NGM_LISTTYPES, 496 "listtypes", 497 NULL, 498 &ng_generic_typeinfo_type 499 }, 500 { 501 NGM_GENERIC_COOKIE, 502 NGM_TEXT_CONFIG, 503 "textconfig", 504 NULL, 505 &ng_parse_string_type 506 }, 507 { 508 NGM_GENERIC_COOKIE, 509 NGM_TEXT_STATUS, 510 "textstatus", 511 NULL, 512 &ng_parse_string_type 513 }, 514 { 515 NGM_GENERIC_COOKIE, 516 NGM_ASCII2BINARY, 517 "ascii2binary", 518 &ng_parse_ng_mesg_type, 519 &ng_parse_ng_mesg_type 520 }, 521 { 522 NGM_GENERIC_COOKIE, 523 NGM_BINARY2ASCII, 524 "binary2ascii", 525 &ng_parse_ng_mesg_type, 526 &ng_parse_ng_mesg_type 527 }, 528 { 0 } 529 }; 530 531 /************************************************************************ 532 Node routines 533 ************************************************************************/ 534 535 /* 536 * Instantiate a node of the requested type 537 */ 538 int 539 ng_make_node(const char *typename, node_p *nodepp) 540 { 541 struct ng_type *type; 542 int error; 543 544 /* Check that the type makes sense */ 545 if (typename == NULL) { 546 TRAP_ERROR(); 547 return (EINVAL); 548 } 549 550 /* Locate the node type */ 551 if ((type = ng_findtype(typename)) == NULL) { 552 char filename[NG_TYPESIZ + 3]; 553 linker_file_t lf; 554 int error; 555 556 /* Not found, try to load it as a loadable module */ 557 snprintf(filename, sizeof(filename), "ng_%s", typename); 558 error = linker_load_module(NULL, filename, NULL, NULL, &lf); 559 if (error != 0) 560 return (error); 561 lf->userrefs++; /* pretend loaded by the syscall */ 562 563 /* Try again, as now the type should have linked itself in */ 564 if ((type = ng_findtype(typename)) == NULL) 565 return (ENXIO); 566 } 567 568 /* 569 * If we have a constructor, then make the node and 570 * call the constructor to do type specific initialisation. 571 */ 572 if (type->constructor != NULL) { 573 if ((error = ng_make_node_common(type, nodepp)) == 0) { 574 if ((error = ((*type->constructor)(*nodepp)) != 0)) { 575 NG_NODE_UNREF(*nodepp); 576 } 577 } 578 } else { 579 /* 580 * Node has no constructor. We cannot ask for one 581 * to be made. It must be brought into existance by 582 * some external agency. The external agency should 583 * call ng_make_node_common() directly to get the 584 * netgraph part initialised. 585 */ 586 TRAP_ERROR(); 587 error = EINVAL; 588 } 589 return (error); 590 } 591 592 /* 593 * Generic node creation. Called by node initialisation for externally 594 * instantiated nodes (e.g. hardware, sockets, etc ). 595 * The returned node has a reference count of 1. 596 */ 597 int 598 ng_make_node_common(struct ng_type *type, node_p *nodepp) 599 { 600 node_p node; 601 602 /* Require the node type to have been already installed */ 603 if (ng_findtype(type->name) == NULL) { 604 TRAP_ERROR(); 605 return (EINVAL); 606 } 607 608 /* Make a node and try attach it to the type */ 609 NG_ALLOC_NODE(node); 610 if (node == NULL) { 611 TRAP_ERROR(); 612 return (ENOMEM); 613 } 614 node->nd_type = type; 615 NG_NODE_REF(node); /* note reference */ 616 type->refs++; 617 618 mtx_init(&node->nd_input_queue.q_mtx, "ng_node", NULL, MTX_SPIN); 619 node->nd_input_queue.queue = NULL; 620 node->nd_input_queue.last = &node->nd_input_queue.queue; 621 node->nd_input_queue.q_flags = 0; 622 node->nd_input_queue.q_node = node; 623 624 /* Initialize hook list for new node */ 625 LIST_INIT(&node->nd_hooks); 626 627 /* Link us into the node linked list */ 628 mtx_lock(&ng_nodelist_mtx); 629 LIST_INSERT_HEAD(&ng_nodelist, node, nd_nodes); 630 mtx_unlock(&ng_nodelist_mtx); 631 632 633 /* get an ID and put us in the hash chain */ 634 mtx_lock(&ng_idhash_mtx); 635 for (;;) { /* wrap protection, even if silly */ 636 node_p node2 = NULL; 637 node->nd_ID = nextID++; /* 137/second for 1 year before wrap */ 638 639 /* Is there a problem with the new number? */ 640 NG_IDHASH_FIND(node->nd_ID, node2); /* already taken? */ 641 if ((node->nd_ID != 0) && (node2 == NULL)) { 642 break; 643 } 644 } 645 LIST_INSERT_HEAD(&ng_ID_hash[NG_IDHASH_FN(node->nd_ID)], 646 node, nd_idnodes); 647 mtx_unlock(&ng_idhash_mtx); 648 649 /* Done */ 650 *nodepp = node; 651 return (0); 652 } 653 654 /* 655 * Forceably start the shutdown process on a node. Either call 656 * it's shutdown method, or do the default shutdown if there is 657 * no type-specific method. 658 * 659 * We can only be called form a shutdown message, so we know we have 660 * a writer lock, and therefore exclusive access. It also means 661 * that we should not be on the work queue, but we check anyhow. 662 * 663 * Persistent node types must have a type-specific method which 664 * Allocates a new node in which case, this one is irretrievably going away, 665 * or cleans up anything it needs, and just makes the node valid again, 666 * in which case we allow the node to survive. 667 * 668 * XXX We need to think of how to tell a persistant node that we 669 * REALLY need to go away because the hardware has gone or we 670 * are rebooting.... etc. 671 */ 672 void 673 ng_rmnode(node_p node, hook_p dummy1, void *dummy2, int dummy3) 674 { 675 hook_p hook; 676 677 /* Check if it's already shutting down */ 678 if ((node->nd_flags & NG_CLOSING) != 0) 679 return; 680 681 if (node == &ng_deadnode) { 682 printf ("shutdown called on deadnode\n"); 683 return; 684 } 685 686 /* Add an extra reference so it doesn't go away during this */ 687 NG_NODE_REF(node); 688 689 /* 690 * Mark it invalid so any newcomers know not to try use it 691 * Also add our own mark so we can't recurse 692 * note that NG_INVALID does not do this as it's also set during 693 * creation 694 */ 695 node->nd_flags |= NG_INVALID|NG_CLOSING; 696 697 /* Notify all remaining connected nodes to disconnect */ 698 while ((hook = LIST_FIRST(&node->nd_hooks)) != NULL) 699 ng_destroy_hook(hook); 700 701 /* 702 * Drain the input queue forceably. 703 * it has no hooks so what's it going to do, bleed on someone? 704 * Theoretically we came here from a queue entry that was added 705 * Just before the queue was closed, so it should be empty anyway. 706 * Also removes us from worklist if needed. 707 */ 708 ng_flush_input_queue(&node->nd_input_queue); 709 710 /* Ask the type if it has anything to do in this case */ 711 if (node->nd_type && node->nd_type->shutdown) { 712 (*node->nd_type->shutdown)(node); 713 if (NG_NODE_IS_VALID(node)) { 714 /* 715 * Well, blow me down if the node code hasn't declared 716 * that it doesn't want to die. 717 * Presumably it is a persistant node. 718 * If we REALLY want it to go away, 719 * e.g. hardware going away, 720 * Our caller should set NG_REALLY_DIE in nd_flags. 721 */ 722 node->nd_flags &= ~(NG_INVALID|NG_CLOSING); 723 NG_NODE_UNREF(node); /* Assume they still have theirs */ 724 return; 725 } 726 } else { /* do the default thing */ 727 NG_NODE_UNREF(node); 728 } 729 730 ng_unname(node); /* basically a NOP these days */ 731 732 /* 733 * Remove extra reference, possibly the last 734 * Possible other holders of references may include 735 * timeout callouts, but theoretically the node's supposed to 736 * have cancelled them. Possibly hardware dependencies may 737 * force a driver to 'linger' with a reference. 738 */ 739 NG_NODE_UNREF(node); 740 } 741 742 #ifdef NETGRAPH_DEBUG 743 void 744 ng_ref_node(node_p node) 745 { 746 _NG_NODE_REF(node); 747 } 748 #endif 749 750 /* 751 * Remove a reference to the node, possibly the last. 752 * deadnode always acts as it it were the last. 753 */ 754 int 755 ng_unref_node(node_p node) 756 { 757 int v; 758 759 if (node == &ng_deadnode) { 760 return (0); 761 } 762 763 do { 764 v = node->nd_refs - 1; 765 } while (! atomic_cmpset_int(&node->nd_refs, v + 1, v)); 766 767 if (v == 0) { /* we were the last */ 768 769 mtx_lock(&ng_nodelist_mtx); 770 node->nd_type->refs--; /* XXX maybe should get types lock? */ 771 LIST_REMOVE(node, nd_nodes); 772 mtx_unlock(&ng_nodelist_mtx); 773 774 mtx_lock(&ng_idhash_mtx); 775 LIST_REMOVE(node, nd_idnodes); 776 mtx_unlock(&ng_idhash_mtx); 777 778 mtx_destroy(&node->nd_input_queue.q_mtx); 779 NG_FREE_NODE(node); 780 } 781 return (v); 782 } 783 784 /************************************************************************ 785 Node ID handling 786 ************************************************************************/ 787 static node_p 788 ng_ID2noderef(ng_ID_t ID) 789 { 790 node_p node; 791 mtx_lock(&ng_idhash_mtx); 792 NG_IDHASH_FIND(ID, node); 793 if(node) 794 NG_NODE_REF(node); 795 mtx_unlock(&ng_idhash_mtx); 796 return(node); 797 } 798 799 ng_ID_t 800 ng_node2ID(node_p node) 801 { 802 return (node ? NG_NODE_ID(node) : 0); 803 } 804 805 /************************************************************************ 806 Node name handling 807 ************************************************************************/ 808 809 /* 810 * Assign a node a name. Once assigned, the name cannot be changed. 811 */ 812 int 813 ng_name_node(node_p node, const char *name) 814 { 815 int i; 816 node_p node2; 817 818 /* Check the name is valid */ 819 for (i = 0; i < NG_NODESIZ; i++) { 820 if (name[i] == '\0' || name[i] == '.' || name[i] == ':') 821 break; 822 } 823 if (i == 0 || name[i] != '\0') { 824 TRAP_ERROR(); 825 return (EINVAL); 826 } 827 if (ng_decodeidname(name) != 0) { /* valid IDs not allowed here */ 828 TRAP_ERROR(); 829 return (EINVAL); 830 } 831 832 /* Check the name isn't already being used */ 833 if ((node2 = ng_name2noderef(node, name)) != NULL) { 834 NG_NODE_UNREF(node2); 835 TRAP_ERROR(); 836 return (EADDRINUSE); 837 } 838 839 /* copy it */ 840 strlcpy(NG_NODE_NAME(node), name, NG_NODESIZ); 841 842 return (0); 843 } 844 845 /* 846 * Find a node by absolute name. The name should NOT end with ':' 847 * The name "." means "this node" and "[xxx]" means "the node 848 * with ID (ie, at address) xxx". 849 * 850 * Returns the node if found, else NULL. 851 * Eventually should add something faster than a sequential search. 852 * Note it aquires a reference on the node so you can be sure it's still there. 853 */ 854 node_p 855 ng_name2noderef(node_p here, const char *name) 856 { 857 node_p node; 858 ng_ID_t temp; 859 860 /* "." means "this node" */ 861 if (strcmp(name, ".") == 0) { 862 NG_NODE_REF(here); 863 return(here); 864 } 865 866 /* Check for name-by-ID */ 867 if ((temp = ng_decodeidname(name)) != 0) { 868 return (ng_ID2noderef(temp)); 869 } 870 871 /* Find node by name */ 872 mtx_lock(&ng_nodelist_mtx); 873 LIST_FOREACH(node, &ng_nodelist, nd_nodes) { 874 if (NG_NODE_IS_VALID(node) 875 && NG_NODE_HAS_NAME(node) 876 && (strcmp(NG_NODE_NAME(node), name) == 0)) { 877 break; 878 } 879 } 880 if (node) 881 NG_NODE_REF(node); 882 mtx_unlock(&ng_nodelist_mtx); 883 return (node); 884 } 885 886 /* 887 * Decode an ID name, eg. "[f03034de]". Returns 0 if the 888 * string is not valid, otherwise returns the value. 889 */ 890 static ng_ID_t 891 ng_decodeidname(const char *name) 892 { 893 const int len = strlen(name); 894 char *eptr; 895 u_long val; 896 897 /* Check for proper length, brackets, no leading junk */ 898 if ((len < 3) 899 || (name[0] != '[') 900 || (name[len - 1] != ']') 901 || (!isxdigit(name[1]))) { 902 return ((ng_ID_t)0); 903 } 904 905 /* Decode number */ 906 val = strtoul(name + 1, &eptr, 16); 907 if ((eptr - name != len - 1) 908 || (val == ULONG_MAX) 909 || (val == 0)) { 910 return ((ng_ID_t)0); 911 } 912 return (ng_ID_t)val; 913 } 914 915 /* 916 * Remove a name from a node. This should only be called 917 * when shutting down and removing the node. 918 * IF we allow name changing this may be more resurected. 919 */ 920 void 921 ng_unname(node_p node) 922 { 923 } 924 925 /************************************************************************ 926 Hook routines 927 Names are not optional. Hooks are always connected, except for a 928 brief moment within these routines. On invalidation or during creation 929 they are connected to the 'dead' hook. 930 ************************************************************************/ 931 932 /* 933 * Remove a hook reference 934 */ 935 void 936 ng_unref_hook(hook_p hook) 937 { 938 int v; 939 940 if (hook == &ng_deadhook) { 941 return; 942 } 943 do { 944 v = hook->hk_refs; 945 } while (! atomic_cmpset_int(&hook->hk_refs, v, v - 1)); 946 947 if (v == 1) { /* we were the last */ 948 if (_NG_HOOK_NODE(hook)) { /* it'll probably be ng_deadnode */ 949 _NG_NODE_UNREF((_NG_HOOK_NODE(hook))); 950 hook->hk_node = NULL; 951 } 952 NG_FREE_HOOK(hook); 953 } 954 } 955 956 /* 957 * Add an unconnected hook to a node. Only used internally. 958 * Assumes node is locked. (XXX not yet true ) 959 */ 960 static int 961 ng_add_hook(node_p node, const char *name, hook_p *hookp) 962 { 963 hook_p hook; 964 int error = 0; 965 966 /* Check that the given name is good */ 967 if (name == NULL) { 968 TRAP_ERROR(); 969 return (EINVAL); 970 } 971 if (ng_findhook(node, name) != NULL) { 972 TRAP_ERROR(); 973 return (EEXIST); 974 } 975 976 /* Allocate the hook and link it up */ 977 NG_ALLOC_HOOK(hook); 978 if (hook == NULL) { 979 TRAP_ERROR(); 980 return (ENOMEM); 981 } 982 hook->hk_refs = 1; /* add a reference for us to return */ 983 hook->hk_flags = HK_INVALID; 984 hook->hk_peer = &ng_deadhook; /* start off this way */ 985 hook->hk_node = node; 986 NG_NODE_REF(node); /* each hook counts as a reference */ 987 988 /* Set hook name */ 989 strlcpy(NG_HOOK_NAME(hook), name, NG_HOOKSIZ); 990 991 /* 992 * Check if the node type code has something to say about it 993 * If it fails, the unref of the hook will also unref the node. 994 */ 995 if (node->nd_type->newhook != NULL) { 996 if ((error = (*node->nd_type->newhook)(node, hook, name))) { 997 NG_HOOK_UNREF(hook); /* this frees the hook */ 998 return (error); 999 } 1000 } 1001 /* 1002 * The 'type' agrees so far, so go ahead and link it in. 1003 * We'll ask again later when we actually connect the hooks. 1004 */ 1005 LIST_INSERT_HEAD(&node->nd_hooks, hook, hk_hooks); 1006 node->nd_numhooks++; 1007 NG_HOOK_REF(hook); /* one for the node */ 1008 1009 if (hookp) 1010 *hookp = hook; 1011 return (0); 1012 } 1013 1014 /* 1015 * Find a hook 1016 * 1017 * Node types may supply their own optimized routines for finding 1018 * hooks. If none is supplied, we just do a linear search. 1019 * XXX Possibly we should add a reference to the hook? 1020 */ 1021 hook_p 1022 ng_findhook(node_p node, const char *name) 1023 { 1024 hook_p hook; 1025 1026 if (node->nd_type->findhook != NULL) 1027 return (*node->nd_type->findhook)(node, name); 1028 LIST_FOREACH(hook, &node->nd_hooks, hk_hooks) { 1029 if (NG_HOOK_IS_VALID(hook) 1030 && (strcmp(NG_HOOK_NAME(hook), name) == 0)) 1031 return (hook); 1032 } 1033 return (NULL); 1034 } 1035 1036 /* 1037 * Destroy a hook 1038 * 1039 * As hooks are always attached, this really destroys two hooks. 1040 * The one given, and the one attached to it. Disconnect the hooks 1041 * from each other first. We reconnect the peer hook to the 'dead' 1042 * hook so that it can still exist after we depart. We then 1043 * send the peer its own destroy message. This ensures that we only 1044 * interact with the peer's structures when it is locked processing that 1045 * message. We hold a reference to the peer hook so we are guaranteed that 1046 * the peer hook and node are still going to exist until 1047 * we are finished there as the hook holds a ref on the node. 1048 * We run this same code again on the peer hook, but that time it is already 1049 * attached to the 'dead' hook. 1050 * 1051 * This routine is called at all stages of hook creation 1052 * on error detection and must be able to handle any such stage. 1053 */ 1054 void 1055 ng_destroy_hook(hook_p hook) 1056 { 1057 hook_p peer = NG_HOOK_PEER(hook); 1058 node_p node = NG_HOOK_NODE(hook); 1059 1060 if (hook == &ng_deadhook) { /* better safe than sorry */ 1061 printf("ng_destroy_hook called on deadhook\n"); 1062 return; 1063 } 1064 hook->hk_flags |= HK_INVALID; /* as soon as possible */ 1065 if (peer && (peer != &ng_deadhook)) { 1066 /* 1067 * Set the peer to point to ng_deadhook 1068 * from this moment on we are effectively independent it. 1069 * send it an rmhook message of it's own. 1070 */ 1071 peer->hk_peer = &ng_deadhook; /* They no longer know us */ 1072 hook->hk_peer = &ng_deadhook; /* Nor us, them */ 1073 if (NG_HOOK_NODE(peer) == &ng_deadnode) { 1074 /* 1075 * If it's already divorced from a node, 1076 * just free it. 1077 */ 1078 /* nothing */ 1079 } else { 1080 ng_rmhook_self(peer); /* Send it a surprise */ 1081 } 1082 NG_HOOK_UNREF(peer); /* account for peer link */ 1083 NG_HOOK_UNREF(hook); /* account for peer link */ 1084 } 1085 1086 /* 1087 * Remove the hook from the node's list to avoid possible recursion 1088 * in case the disconnection results in node shutdown. 1089 */ 1090 if (node == &ng_deadnode) { /* happens if called from ng_con_nodes() */ 1091 return; 1092 } 1093 LIST_REMOVE(hook, hk_hooks); 1094 node->nd_numhooks--; 1095 if (node->nd_type->disconnect) { 1096 /* 1097 * The type handler may elect to destroy the node so don't 1098 * trust its existance after this point. (except 1099 * that we still hold a reference on it. (which we 1100 * inherrited from the hook we are destroying) 1101 */ 1102 (*node->nd_type->disconnect) (hook); 1103 } 1104 1105 /* 1106 * Note that because we will point to ng_deadnode, the original node 1107 * is not decremented automatically so we do that manually. 1108 */ 1109 _NG_HOOK_NODE(hook) = &ng_deadnode; 1110 NG_NODE_UNREF(node); /* We no longer point to it so adjust count */ 1111 NG_HOOK_UNREF(hook); /* Account for linkage (in list) to node */ 1112 } 1113 1114 /* 1115 * Take two hooks on a node and merge the connection so that the given node 1116 * is effectively bypassed. 1117 */ 1118 int 1119 ng_bypass(hook_p hook1, hook_p hook2) 1120 { 1121 if (hook1->hk_node != hook2->hk_node) { 1122 TRAP_ERROR(); 1123 return (EINVAL); 1124 } 1125 hook1->hk_peer->hk_peer = hook2->hk_peer; 1126 hook2->hk_peer->hk_peer = hook1->hk_peer; 1127 1128 hook1->hk_peer = &ng_deadhook; 1129 hook2->hk_peer = &ng_deadhook; 1130 1131 /* XXX If we ever cache methods on hooks update them as well */ 1132 ng_destroy_hook(hook1); 1133 ng_destroy_hook(hook2); 1134 return (0); 1135 } 1136 1137 /* 1138 * Install a new netgraph type 1139 */ 1140 int 1141 ng_newtype(struct ng_type *tp) 1142 { 1143 const size_t namelen = strlen(tp->name); 1144 1145 /* Check version and type name fields */ 1146 if ((tp->version != NG_ABI_VERSION) 1147 || (namelen == 0) 1148 || (namelen >= NG_TYPESIZ)) { 1149 TRAP_ERROR(); 1150 return (EINVAL); 1151 } 1152 1153 /* Check for name collision */ 1154 if (ng_findtype(tp->name) != NULL) { 1155 TRAP_ERROR(); 1156 return (EEXIST); 1157 } 1158 1159 1160 /* Link in new type */ 1161 mtx_lock(&ng_typelist_mtx); 1162 LIST_INSERT_HEAD(&ng_typelist, tp, types); 1163 tp->refs = 1; /* first ref is linked list */ 1164 mtx_unlock(&ng_typelist_mtx); 1165 return (0); 1166 } 1167 1168 /* 1169 * unlink a netgraph type 1170 * If no examples exist 1171 */ 1172 int 1173 ng_rmtype(struct ng_type *tp) 1174 { 1175 /* Check for name collision */ 1176 if (tp->refs != 1) { 1177 TRAP_ERROR(); 1178 return (EBUSY); 1179 } 1180 1181 /* Unlink type */ 1182 mtx_lock(&ng_typelist_mtx); 1183 LIST_REMOVE(tp, types); 1184 mtx_unlock(&ng_typelist_mtx); 1185 return (0); 1186 } 1187 1188 /* 1189 * Look for a type of the name given 1190 */ 1191 struct ng_type * 1192 ng_findtype(const char *typename) 1193 { 1194 struct ng_type *type; 1195 1196 mtx_lock(&ng_typelist_mtx); 1197 LIST_FOREACH(type, &ng_typelist, types) { 1198 if (strcmp(type->name, typename) == 0) 1199 break; 1200 } 1201 mtx_unlock(&ng_typelist_mtx); 1202 return (type); 1203 } 1204 1205 /************************************************************************ 1206 Composite routines 1207 ************************************************************************/ 1208 /* 1209 * Connect two nodes using the specified hooks, using queued functions. 1210 */ 1211 static void 1212 ng_con_part3(node_p node, hook_p hook, void *arg1, int arg2) 1213 { 1214 1215 /* 1216 * When we run, we know that the node 'node' is locked for us. 1217 * Our caller has a reference on the hook. 1218 * Our caller has a reference on the node. 1219 * (In this case our caller is ng_apply_item() ). 1220 * The peer hook has a reference on the hook. 1221 * We are all set up except for the final call to the node, and 1222 * the clearing of the INVALID flag. 1223 */ 1224 if (NG_HOOK_NODE(hook) == &ng_deadnode) { 1225 /* 1226 * The node must have been freed again since we last visited 1227 * here. ng_destry_hook() has this effect but nothing else does. 1228 * We should just release our references and 1229 * free anything we can think of. 1230 * Since we know it's been destroyed, and it's our caller 1231 * that holds the references, just return. 1232 */ 1233 return ; 1234 } 1235 if (hook->hk_node->nd_type->connect) { 1236 if ((*hook->hk_node->nd_type->connect) (hook)) { 1237 ng_destroy_hook(hook); /* also zaps peer */ 1238 printf("failed in ng_con_part3()\n"); 1239 return ; 1240 } 1241 } 1242 /* 1243 * XXX this is wrong for SMP. Possibly we need 1244 * to separate out 'create' and 'invalid' flags. 1245 * should only set flags on hooks we have locked under our node. 1246 */ 1247 hook->hk_flags &= ~HK_INVALID; 1248 return ; 1249 } 1250 1251 static void 1252 ng_con_part2(node_p node, hook_p hook, void *arg1, int arg2) 1253 { 1254 1255 /* 1256 * When we run, we know that the node 'node' is locked for us. 1257 * Our caller has a reference on the hook. 1258 * Our caller has a reference on the node. 1259 * (In this case our caller is ng_apply_item() ). 1260 * The peer hook has a reference on the hook. 1261 * our node pointer points to the 'dead' node. 1262 * First check the hook name is unique. 1263 * Should not happen because we checked before queueing this. 1264 */ 1265 if (ng_findhook(node, NG_HOOK_NAME(hook)) != NULL) { 1266 TRAP_ERROR(); 1267 ng_destroy_hook(hook); /* should destroy peer too */ 1268 printf("failed in ng_con_part2()\n"); 1269 return ; 1270 } 1271 /* 1272 * Check if the node type code has something to say about it 1273 * If it fails, the unref of the hook will also unref the attached node, 1274 * however since that node is 'ng_deadnode' this will do nothing. 1275 * The peer hook will also be destroyed. 1276 */ 1277 if (node->nd_type->newhook != NULL) { 1278 if ((*node->nd_type->newhook)(node, hook, hook->hk_name)) { 1279 ng_destroy_hook(hook); /* should destroy peer too */ 1280 printf("failed in ng_con_part2()\n"); 1281 return ; 1282 } 1283 } 1284 1285 /* 1286 * The 'type' agrees so far, so go ahead and link it in. 1287 * We'll ask again later when we actually connect the hooks. 1288 */ 1289 hook->hk_node = node; /* just overwrite ng_deadnode */ 1290 NG_NODE_REF(node); /* each hook counts as a reference */ 1291 LIST_INSERT_HEAD(&node->nd_hooks, hook, hk_hooks); 1292 node->nd_numhooks++; 1293 NG_HOOK_REF(hook); /* one for the node */ 1294 1295 /* 1296 * We now have a symetrical situation, where both hooks have been 1297 * linked to their nodes, the newhook methods have been called 1298 * And the references are all correct. The hooks are still marked 1299 * as invalid, as we have not called the 'connect' methods 1300 * yet. 1301 * We can call the local one immediatly as we have the 1302 * node locked, but we need to queue the remote one. 1303 */ 1304 if (hook->hk_node->nd_type->connect) { 1305 if ((*hook->hk_node->nd_type->connect) (hook)) { 1306 ng_destroy_hook(hook); /* also zaps peer */ 1307 printf("failed in ng_con_part2(A)\n"); 1308 return ; 1309 } 1310 } 1311 if (ng_send_fn(hook->hk_peer->hk_node, hook->hk_peer, 1312 &ng_con_part3, arg1, arg2)) { 1313 printf("failed in ng_con_part2(B)"); 1314 ng_destroy_hook(hook); /* also zaps peer */ 1315 return ; 1316 } 1317 hook->hk_flags &= ~HK_INVALID; /* need both to be able to work */ 1318 return ; 1319 } 1320 1321 /* 1322 * Connect this node with another node. We assume that this node is 1323 * currently locked, as we are only called from an NGM_CONNECT message. 1324 */ 1325 static int 1326 ng_con_nodes(node_p node, const char *name, node_p node2, const char *name2) 1327 { 1328 int error; 1329 hook_p hook; 1330 hook_p hook2; 1331 1332 if (ng_findhook(node2, name2) != NULL) { 1333 return(EEXIST); 1334 } 1335 if ((error = ng_add_hook(node, name, &hook))) /* gives us a ref */ 1336 return (error); 1337 /* Allocate the other hook and link it up */ 1338 NG_ALLOC_HOOK(hook2); 1339 if (hook == NULL) { 1340 TRAP_ERROR(); 1341 ng_destroy_hook(hook); /* XXX check ref counts so far */ 1342 NG_HOOK_UNREF(hook); /* including our ref */ 1343 return (ENOMEM); 1344 } 1345 hook2->hk_refs = 1; /* start with a reference for us. */ 1346 hook2->hk_flags = HK_INVALID; 1347 hook2->hk_peer = hook; /* Link the two together */ 1348 hook->hk_peer = hook2; 1349 NG_HOOK_REF(hook); /* Add a ref for the peer to each*/ 1350 NG_HOOK_REF(hook2); 1351 hook2->hk_node = &ng_deadnode; 1352 strlcpy(NG_HOOK_NAME(hook2), name2, NG_HOOKSIZ); 1353 1354 /* 1355 * Queue the function above. 1356 * Procesing continues in that function in the lock context of 1357 * the other node. 1358 */ 1359 ng_send_fn(node2, hook2, &ng_con_part2, NULL, 0); 1360 1361 NG_HOOK_UNREF(hook); /* Let each hook go if it wants to */ 1362 NG_HOOK_UNREF(hook2); 1363 return (0); 1364 } 1365 1366 /* 1367 * Make a peer and connect. 1368 * We assume that the local node is locked. 1369 * The new node probably doesn't need a lock until 1370 * it has a hook, because it cannot really have any work until then, 1371 * but we should think about it a bit more. 1372 * 1373 * The problem may come if the other node also fires up 1374 * some hardware or a timer or some other source of activation, 1375 * also it may already get a command msg via it's ID. 1376 * 1377 * We could use the same method as ng_con_nodes() but we'd have 1378 * to add ability to remove the node when failing. (Not hard, just 1379 * make arg1 point to the node to remove). 1380 * Unless of course we just ignore failure to connect and leave 1381 * an unconnected node? 1382 */ 1383 static int 1384 ng_mkpeer(node_p node, const char *name, const char *name2, char *type) 1385 { 1386 node_p node2; 1387 hook_p hook1; 1388 hook_p hook2; 1389 int error; 1390 1391 if ((error = ng_make_node(type, &node2))) { 1392 return (error); 1393 } 1394 1395 if ((error = ng_add_hook(node, name, &hook1))) { /* gives us a ref */ 1396 ng_rmnode(node2, NULL, NULL, 0); 1397 return (error); 1398 } 1399 1400 if ((error = ng_add_hook(node2, name2, &hook2))) { 1401 ng_rmnode(node2, NULL, NULL, 0); 1402 ng_destroy_hook(hook1); 1403 NG_HOOK_UNREF(hook1); 1404 return (error); 1405 } 1406 1407 /* 1408 * Actually link the two hooks together. 1409 */ 1410 hook1->hk_peer = hook2; 1411 hook2->hk_peer = hook1; 1412 1413 /* Each hook is referenced by the other */ 1414 NG_HOOK_REF(hook1); 1415 NG_HOOK_REF(hook2); 1416 1417 /* Give each node the opportunity to veto the pending connection */ 1418 if (hook1->hk_node->nd_type->connect) { 1419 error = (*hook1->hk_node->nd_type->connect) (hook1); 1420 } 1421 1422 if ((error == 0) && hook2->hk_node->nd_type->connect) { 1423 error = (*hook2->hk_node->nd_type->connect) (hook2); 1424 1425 } 1426 1427 /* 1428 * drop the references we were holding on the two hooks. 1429 */ 1430 if (error) { 1431 ng_destroy_hook(hook2); /* also zaps hook1 */ 1432 ng_rmnode(node2, NULL, NULL, 0); 1433 } else { 1434 /* As a last act, allow the hooks to be used */ 1435 hook1->hk_flags &= ~HK_INVALID; 1436 hook2->hk_flags &= ~HK_INVALID; 1437 } 1438 NG_HOOK_UNREF(hook1); 1439 NG_HOOK_UNREF(hook2); 1440 return (error); 1441 } 1442 1443 /************************************************************************ 1444 Utility routines to send self messages 1445 ************************************************************************/ 1446 1447 /* Shut this node down as soon as everyone is clear of it */ 1448 /* Should add arg "immediatly" to jump the queue */ 1449 int 1450 ng_rmnode_self(node_p node) 1451 { 1452 int error; 1453 1454 if (node == &ng_deadnode) 1455 return (0); 1456 node->nd_flags |= NG_INVALID; 1457 if (node->nd_flags & NG_CLOSING) 1458 return (0); 1459 1460 error = ng_send_fn(node, NULL, &ng_rmnode, NULL, 0); 1461 return (error); 1462 } 1463 1464 static void 1465 ng_rmhook_part2(node_p node, hook_p hook, void *arg1, int arg2) 1466 { 1467 ng_destroy_hook(hook); 1468 return ; 1469 } 1470 1471 int 1472 ng_rmhook_self(hook_p hook) 1473 { 1474 int error; 1475 node_p node = NG_HOOK_NODE(hook); 1476 1477 if (node == &ng_deadnode) 1478 return (0); 1479 1480 error = ng_send_fn(node, hook, &ng_rmhook_part2, NULL, 0); 1481 return (error); 1482 } 1483 1484 /*********************************************************************** 1485 * Parse and verify a string of the form: <NODE:><PATH> 1486 * 1487 * Such a string can refer to a specific node or a specific hook 1488 * on a specific node, depending on how you look at it. In the 1489 * latter case, the PATH component must not end in a dot. 1490 * 1491 * Both <NODE:> and <PATH> are optional. The <PATH> is a string 1492 * of hook names separated by dots. This breaks out the original 1493 * string, setting *nodep to "NODE" (or NULL if none) and *pathp 1494 * to "PATH" (or NULL if degenerate). Also, *hookp will point to 1495 * the final hook component of <PATH>, if any, otherwise NULL. 1496 * 1497 * This returns -1 if the path is malformed. The char ** are optional. 1498 ***********************************************************************/ 1499 int 1500 ng_path_parse(char *addr, char **nodep, char **pathp, char **hookp) 1501 { 1502 char *node, *path, *hook; 1503 int k; 1504 1505 /* 1506 * Extract absolute NODE, if any 1507 */ 1508 for (path = addr; *path && *path != ':'; path++); 1509 if (*path) { 1510 node = addr; /* Here's the NODE */ 1511 *path++ = '\0'; /* Here's the PATH */ 1512 1513 /* Node name must not be empty */ 1514 if (!*node) 1515 return -1; 1516 1517 /* A name of "." is OK; otherwise '.' not allowed */ 1518 if (strcmp(node, ".") != 0) { 1519 for (k = 0; node[k]; k++) 1520 if (node[k] == '.') 1521 return -1; 1522 } 1523 } else { 1524 node = NULL; /* No absolute NODE */ 1525 path = addr; /* Here's the PATH */ 1526 } 1527 1528 /* Snoop for illegal characters in PATH */ 1529 for (k = 0; path[k]; k++) 1530 if (path[k] == ':') 1531 return -1; 1532 1533 /* Check for no repeated dots in PATH */ 1534 for (k = 0; path[k]; k++) 1535 if (path[k] == '.' && path[k + 1] == '.') 1536 return -1; 1537 1538 /* Remove extra (degenerate) dots from beginning or end of PATH */ 1539 if (path[0] == '.') 1540 path++; 1541 if (*path && path[strlen(path) - 1] == '.') 1542 path[strlen(path) - 1] = 0; 1543 1544 /* If PATH has a dot, then we're not talking about a hook */ 1545 if (*path) { 1546 for (hook = path, k = 0; path[k]; k++) 1547 if (path[k] == '.') { 1548 hook = NULL; 1549 break; 1550 } 1551 } else 1552 path = hook = NULL; 1553 1554 /* Done */ 1555 if (nodep) 1556 *nodep = node; 1557 if (pathp) 1558 *pathp = path; 1559 if (hookp) 1560 *hookp = hook; 1561 return (0); 1562 } 1563 1564 /* 1565 * Given a path, which may be absolute or relative, and a starting node, 1566 * return the destination node. 1567 */ 1568 int 1569 ng_path2noderef(node_p here, const char *address, 1570 node_p *destp, hook_p *lasthook) 1571 { 1572 char fullpath[NG_PATHSIZ]; 1573 char *nodename, *path, pbuf[2]; 1574 node_p node, oldnode; 1575 char *cp; 1576 hook_p hook = NULL; 1577 1578 /* Initialize */ 1579 if (destp == NULL) { 1580 TRAP_ERROR(); 1581 return EINVAL; 1582 } 1583 *destp = NULL; 1584 1585 /* Make a writable copy of address for ng_path_parse() */ 1586 strncpy(fullpath, address, sizeof(fullpath) - 1); 1587 fullpath[sizeof(fullpath) - 1] = '\0'; 1588 1589 /* Parse out node and sequence of hooks */ 1590 if (ng_path_parse(fullpath, &nodename, &path, NULL) < 0) { 1591 TRAP_ERROR(); 1592 return EINVAL; 1593 } 1594 if (path == NULL) { 1595 pbuf[0] = '.'; /* Needs to be writable */ 1596 pbuf[1] = '\0'; 1597 path = pbuf; 1598 } 1599 1600 /* 1601 * For an absolute address, jump to the starting node. 1602 * Note that this holds a reference on the node for us. 1603 * Don't forget to drop the reference if we don't need it. 1604 */ 1605 if (nodename) { 1606 node = ng_name2noderef(here, nodename); 1607 if (node == NULL) { 1608 TRAP_ERROR(); 1609 return (ENOENT); 1610 } 1611 } else { 1612 if (here == NULL) { 1613 TRAP_ERROR(); 1614 return (EINVAL); 1615 } 1616 node = here; 1617 NG_NODE_REF(node); 1618 } 1619 1620 /* 1621 * Now follow the sequence of hooks 1622 * XXX 1623 * We actually cannot guarantee that the sequence 1624 * is not being demolished as we crawl along it 1625 * without extra-ordinary locking etc. 1626 * So this is a bit dodgy to say the least. 1627 * We can probably hold up some things by holding 1628 * the nodelist mutex for the time of this 1629 * crawl if we wanted.. At least that way we wouldn't have to 1630 * worry about the nodes dissappearing, but the hooks would still 1631 * be a problem. 1632 */ 1633 for (cp = path; node != NULL && *cp != '\0'; ) { 1634 char *segment; 1635 1636 /* 1637 * Break out the next path segment. Replace the dot we just 1638 * found with a NUL; "cp" points to the next segment (or the 1639 * NUL at the end). 1640 */ 1641 for (segment = cp; *cp != '\0'; cp++) { 1642 if (*cp == '.') { 1643 *cp++ = '\0'; 1644 break; 1645 } 1646 } 1647 1648 /* Empty segment */ 1649 if (*segment == '\0') 1650 continue; 1651 1652 /* We have a segment, so look for a hook by that name */ 1653 hook = ng_findhook(node, segment); 1654 1655 /* Can't get there from here... */ 1656 if (hook == NULL 1657 || NG_HOOK_PEER(hook) == NULL 1658 || NG_HOOK_NOT_VALID(hook) 1659 || NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook))) { 1660 TRAP_ERROR(); 1661 NG_NODE_UNREF(node); 1662 #if 0 1663 printf("hooknotvalid %s %s %d %d %d %d ", 1664 path, 1665 segment, 1666 hook == NULL, 1667 NG_HOOK_PEER(hook) == NULL, 1668 NG_HOOK_NOT_VALID(hook), 1669 NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook))); 1670 #endif 1671 return (ENOENT); 1672 } 1673 1674 /* 1675 * Hop on over to the next node 1676 * XXX 1677 * Big race conditions here as hooks and nodes go away 1678 * *** Idea.. store an ng_ID_t in each hook and use that 1679 * instead of the direct hook in this crawl? 1680 */ 1681 oldnode = node; 1682 if ((node = NG_PEER_NODE(hook))) 1683 NG_NODE_REF(node); /* XXX RACE */ 1684 NG_NODE_UNREF(oldnode); /* XXX another race */ 1685 if (NG_NODE_NOT_VALID(node)) { 1686 NG_NODE_UNREF(node); /* XXX more races */ 1687 node = NULL; 1688 } 1689 } 1690 1691 /* If node somehow missing, fail here (probably this is not needed) */ 1692 if (node == NULL) { 1693 TRAP_ERROR(); 1694 return (ENXIO); 1695 } 1696 1697 /* Done */ 1698 *destp = node; 1699 if (lasthook != NULL) 1700 *lasthook = (hook ? NG_HOOK_PEER(hook) : NULL); 1701 return (0); 1702 } 1703 1704 /***************************************************************\ 1705 * Input queue handling. 1706 * All activities are submitted to the node via the input queue 1707 * which implements a multiple-reader/single-writer gate. 1708 * Items which cannot be handled immeditly are queued. 1709 * 1710 * read-write queue locking inline functions * 1711 \***************************************************************/ 1712 1713 static __inline item_p ng_dequeue(struct ng_queue * ngq); 1714 static __inline item_p ng_acquire_read(struct ng_queue * ngq, 1715 item_p item); 1716 static __inline item_p ng_acquire_write(struct ng_queue * ngq, 1717 item_p item); 1718 static __inline void ng_leave_read(struct ng_queue * ngq); 1719 static __inline void ng_leave_write(struct ng_queue * ngq); 1720 static __inline void ng_queue_rw(struct ng_queue * ngq, 1721 item_p item, int rw); 1722 1723 /* 1724 * Definition of the bits fields in the ng_queue flag word. 1725 * Defined here rather than in netgraph.h because no-one should fiddle 1726 * with them. 1727 * 1728 * The ordering here may be important! don't shuffle these. 1729 */ 1730 /*- 1731 Safety Barrier--------+ (adjustable to suit taste) (not used yet) 1732 | 1733 V 1734 +-------+-------+-------+-------+-------+-------+-------+-------+ 1735 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 1736 | |A|c|t|i|v|e| |R|e|a|d|e|r| |C|o|u|n|t| | | | | | | | | |R|A|W| 1737 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |P|W|P| 1738 +-------+-------+-------+-------+-------+-------+-------+-------+ 1739 \___________________________ ____________________________/ | | | 1740 V | | | 1741 [active reader count] | | | 1742 | | | 1743 Read Pending ------------------------------------+ | | 1744 | | 1745 Active Writer -------------------------------------+ | 1746 | 1747 Write Pending ---------------------------------------+ 1748 1749 1750 */ 1751 #define WRITE_PENDING 0x00000001 1752 #define WRITER_ACTIVE 0x00000002 1753 #define READ_PENDING 0x00000004 1754 #define READER_INCREMENT 0x00000008 1755 #define READER_MASK 0xfffffff0 /* Not valid if WRITER_ACTIVE is set */ 1756 #define SAFETY_BARRIER 0x00100000 /* 64K items queued should be enough */ 1757 1758 /* Defines of more elaborate states on the queue */ 1759 /* Mask of bits a read cares about */ 1760 #define NGQ_RMASK (WRITE_PENDING|WRITER_ACTIVE|READ_PENDING) 1761 1762 /* Mask of bits a write cares about */ 1763 #define NGQ_WMASK (NGQ_RMASK|READER_MASK) 1764 1765 /* tests to decide if we could get a read or write off the queue */ 1766 #define CAN_GET_READ(flag) ((flag & NGQ_RMASK) == READ_PENDING) 1767 #define CAN_GET_WRITE(flag) ((flag & NGQ_WMASK) == WRITE_PENDING) 1768 1769 /* Is there a chance of getting ANY work off the queue? */ 1770 #define CAN_GET_WORK(flag) (CAN_GET_READ(flag) || CAN_GET_WRITE(flag)) 1771 1772 /* 1773 * Taking into account the current state of the queue and node, possibly take 1774 * the next entry off the queue and return it. Return NULL if there was 1775 * nothing we could return, either because there really was nothing there, or 1776 * because the node was in a state where it cannot yet process the next item 1777 * on the queue. 1778 * 1779 * This MUST MUST MUST be called with the mutex held. 1780 */ 1781 static __inline item_p 1782 ng_dequeue(struct ng_queue *ngq) 1783 { 1784 item_p item; 1785 u_int add_arg; 1786 1787 if (CAN_GET_READ(ngq->q_flags)) { 1788 /* 1789 * Head of queue is a reader and we have no write active. 1790 * We don't care how many readers are already active. 1791 * Adjust the flags for the item we are about to dequeue. 1792 * Add the correct increment for the reader count as well. 1793 */ 1794 add_arg = (READER_INCREMENT - READ_PENDING); 1795 } else if (CAN_GET_WRITE(ngq->q_flags)) { 1796 /* 1797 * There is a pending write, no readers and no active writer. 1798 * This means we can go ahead with the pending writer. Note 1799 * the fact that we now have a writer, ready for when we take 1800 * it off the queue. 1801 * 1802 * We don't need to worry about a possible collision with the 1803 * fasttrack reader. 1804 * 1805 * The fasttrack thread may take a long time to discover that we 1806 * are running so we would have an inconsistent state in the 1807 * flags for a while. Since we ignore the reader count 1808 * entirely when the WRITER_ACTIVE flag is set, this should 1809 * not matter (in fact it is defined that way). If it tests 1810 * the flag before this operation, the WRITE_PENDING flag 1811 * will make it fail, and if it tests it later, the 1812 * WRITER_ACTIVE flag will do the same. If it is SO slow that 1813 * we have actually completed the operation, and neither flag 1814 * is set (nor the READ_PENDING) by the time that it tests 1815 * the flags, then it is actually ok for it to continue. If 1816 * it completes and we've finished and the read pending is 1817 * set it still fails. 1818 * 1819 * So we can just ignore it, as long as we can ensure that the 1820 * transition from WRITE_PENDING state to the WRITER_ACTIVE 1821 * state is atomic. 1822 * 1823 * After failing, first it will be held back by the mutex, then 1824 * when it can proceed, it will queue its request, then it 1825 * would arrive at this function. Usually it will have to 1826 * leave empty handed because the ACTIVE WRITER bit will be 1827 * set. 1828 * 1829 * Adjust the flags for the item we are about to dequeue 1830 * and for the new active writer. 1831 */ 1832 add_arg = (WRITER_ACTIVE - WRITE_PENDING); 1833 /* 1834 * We want to write "active writer, no readers " Now go make 1835 * it true. In fact there may be a number in the readers 1836 * count but we know it is not true and will be fixed soon. 1837 * We will fix the flags for the next pending entry in a 1838 * moment. 1839 */ 1840 } else { 1841 /* 1842 * We can't dequeue anything.. return and say so. Probably we 1843 * have a write pending and the readers count is non zero. If 1844 * we got here because a reader hit us just at the wrong 1845 * moment with the fasttrack code, and put us in a strange 1846 * state, then it will be through in just a moment, (as soon 1847 * as we release the mutex) and keep things moving. 1848 * Make sure we remove ourselves from the work queue. 1849 */ 1850 ng_worklist_remove(ngq->q_node); 1851 return (0); 1852 } 1853 1854 /* 1855 * Now we dequeue the request (whatever it may be) and correct the 1856 * pending flags and the next and last pointers. 1857 */ 1858 item = ngq->queue; 1859 ngq->queue = item->el_next; 1860 if (ngq->last == &(item->el_next)) { 1861 /* 1862 * that was the last entry in the queue so set the 'last 1863 * pointer up correctly and make sure the pending flags are 1864 * clear. 1865 */ 1866 ngq->last = &(ngq->queue); 1867 /* 1868 * Whatever flag was set will be cleared and 1869 * the new acive field will be set by the add as well, 1870 * so we don't need to change add_arg. 1871 * But we know we don't need to be on the work list. 1872 */ 1873 atomic_add_long(&ngq->q_flags, add_arg); 1874 ng_worklist_remove(ngq->q_node); 1875 } else { 1876 /* 1877 * Since there is something on the queue, note what it is 1878 * in the flags word. 1879 */ 1880 if ((ngq->queue->el_flags & NGQF_RW) == NGQF_READER) { 1881 add_arg += READ_PENDING; 1882 } else { 1883 add_arg += WRITE_PENDING; 1884 } 1885 atomic_add_long(&ngq->q_flags, add_arg); 1886 /* 1887 * If we see more doable work, make sure we are 1888 * on the work queue. 1889 */ 1890 if (CAN_GET_WORK(ngq->q_flags)) { 1891 ng_setisr(ngq->q_node); 1892 } 1893 } 1894 /* 1895 * We have successfully cleared the old pending flag, set the new one 1896 * if it is needed, and incremented the appropriate active field. 1897 * (all in one atomic addition.. ) 1898 */ 1899 return (item); 1900 } 1901 1902 /* 1903 * Queue a packet to be picked up by someone else. 1904 * We really don't care who, but we can't or don't want to hang around 1905 * to process it ourselves. We are probably an interrupt routine.. 1906 * 1 = writer, 0 = reader 1907 */ 1908 #define NGQRW_R 0 1909 #define NGQRW_W 1 1910 static __inline void 1911 ng_queue_rw(struct ng_queue * ngq, item_p item, int rw) 1912 { 1913 item->el_next = NULL; /* maybe not needed */ 1914 *ngq->last = item; 1915 /* 1916 * If it was the first item in the queue then we need to 1917 * set the last pointer and the type flags. 1918 */ 1919 if (ngq->last == &(ngq->queue)) { 1920 /* 1921 * When called with constants for rw, the optimiser will 1922 * remove the unneeded branch below. 1923 */ 1924 if (rw == NGQRW_W) { 1925 atomic_add_long(&ngq->q_flags, WRITE_PENDING); 1926 } else { 1927 atomic_add_long(&ngq->q_flags, READ_PENDING); 1928 } 1929 } 1930 ngq->last = &(item->el_next); 1931 } 1932 1933 1934 /* 1935 * This function 'cheats' in that it first tries to 'grab' the use of the 1936 * node, without going through the mutex. We can do this becasue of the 1937 * semantics of the lock. The semantics include a clause that says that the 1938 * value of the readers count is invalid if the WRITER_ACTIVE flag is set. It 1939 * also says that the WRITER_ACTIVE flag cannot be set if the readers count 1940 * is not zero. Note that this talks about what is valid to SET the 1941 * WRITER_ACTIVE flag, because from the moment it is set, the value if the 1942 * reader count is immaterial, and not valid. The two 'pending' flags have a 1943 * similar effect, in that If they are orthogonal to the two active fields in 1944 * how they are set, but if either is set, the attempted 'grab' need to be 1945 * backed out because there is earlier work, and we maintain ordering in the 1946 * queue. The result of this is that the reader request can try obtain use of 1947 * the node with only a single atomic addition, and without any of the mutex 1948 * overhead. If this fails the operation degenerates to the same as for other 1949 * cases. 1950 * 1951 */ 1952 static __inline item_p 1953 ng_acquire_read(struct ng_queue *ngq, item_p item) 1954 { 1955 1956 /* ######### Hack alert ######### */ 1957 atomic_add_long(&ngq->q_flags, READER_INCREMENT); 1958 if ((ngq->q_flags & NGQ_RMASK) == 0) { 1959 /* Successfully grabbed node */ 1960 return (item); 1961 } 1962 /* undo the damage if we didn't succeed */ 1963 atomic_subtract_long(&ngq->q_flags, READER_INCREMENT); 1964 1965 /* ######### End Hack alert ######### */ 1966 mtx_lock_spin((&ngq->q_mtx)); 1967 /* 1968 * Try again. Another processor (or interrupt for that matter) may 1969 * have removed the last queued item that was stopping us from 1970 * running, between the previous test, and the moment that we took 1971 * the mutex. (Or maybe a writer completed.) 1972 */ 1973 if ((ngq->q_flags & NGQ_RMASK) == 0) { 1974 atomic_add_long(&ngq->q_flags, READER_INCREMENT); 1975 mtx_unlock_spin((&ngq->q_mtx)); 1976 return (item); 1977 } 1978 1979 /* 1980 * and queue the request for later. 1981 */ 1982 item->el_flags |= NGQF_READER; 1983 ng_queue_rw(ngq, item, NGQRW_R); 1984 1985 /* 1986 * Ok, so that's the item successfully queued for later. So now we 1987 * see if we can dequeue something to run instead. 1988 */ 1989 item = ng_dequeue(ngq); 1990 mtx_unlock_spin(&(ngq->q_mtx)); 1991 return (item); 1992 } 1993 1994 static __inline item_p 1995 ng_acquire_write(struct ng_queue *ngq, item_p item) 1996 { 1997 restart: 1998 mtx_lock_spin(&(ngq->q_mtx)); 1999 /* 2000 * If there are no readers, no writer, and no pending packets, then 2001 * we can just go ahead. In all other situations we need to queue the 2002 * request 2003 */ 2004 if ((ngq->q_flags & NGQ_WMASK) == 0) { 2005 atomic_add_long(&ngq->q_flags, WRITER_ACTIVE); 2006 mtx_unlock_spin((&ngq->q_mtx)); 2007 if (ngq->q_flags & READER_MASK) { 2008 /* Collision with fast-track reader */ 2009 atomic_subtract_long(&ngq->q_flags, WRITER_ACTIVE); 2010 goto restart; 2011 } 2012 return (item); 2013 } 2014 2015 /* 2016 * and queue the request for later. 2017 */ 2018 item->el_flags &= ~NGQF_RW; 2019 ng_queue_rw(ngq, item, NGQRW_W); 2020 2021 /* 2022 * Ok, so that's the item successfully queued for later. So now we 2023 * see if we can dequeue something to run instead. 2024 */ 2025 item = ng_dequeue(ngq); 2026 mtx_unlock_spin(&(ngq->q_mtx)); 2027 return (item); 2028 } 2029 2030 static __inline void 2031 ng_leave_read(struct ng_queue *ngq) 2032 { 2033 atomic_subtract_long(&ngq->q_flags, READER_INCREMENT); 2034 } 2035 2036 static __inline void 2037 ng_leave_write(struct ng_queue *ngq) 2038 { 2039 atomic_subtract_long(&ngq->q_flags, WRITER_ACTIVE); 2040 } 2041 2042 static void 2043 ng_flush_input_queue(struct ng_queue * ngq) 2044 { 2045 item_p item; 2046 u_int add_arg; 2047 mtx_lock_spin(&ngq->q_mtx); 2048 for (;;) { 2049 /* Now take a look at what's on the queue */ 2050 if (ngq->q_flags & READ_PENDING) { 2051 add_arg = -READ_PENDING; 2052 } else if (ngq->q_flags & WRITE_PENDING) { 2053 add_arg = -WRITE_PENDING; 2054 } else { 2055 break; 2056 } 2057 2058 item = ngq->queue; 2059 ngq->queue = item->el_next; 2060 if (ngq->last == &(item->el_next)) { 2061 ngq->last = &(ngq->queue); 2062 } else { 2063 if ((ngq->queue->el_flags & NGQF_RW) == NGQF_READER) { 2064 add_arg += READ_PENDING; 2065 } else { 2066 add_arg += WRITE_PENDING; 2067 } 2068 } 2069 atomic_add_long(&ngq->q_flags, add_arg); 2070 2071 mtx_lock_spin(&ngq->q_mtx); 2072 NG_FREE_ITEM(item); 2073 mtx_unlock_spin(&ngq->q_mtx); 2074 } 2075 /* 2076 * Take us off the work queue if we are there. 2077 * We definatly have no work to be done. 2078 */ 2079 ng_worklist_remove(ngq->q_node); 2080 mtx_unlock_spin(&ngq->q_mtx); 2081 } 2082 2083 /*********************************************************************** 2084 * Externally visible method for sending or queueing messages or data. 2085 ***********************************************************************/ 2086 2087 /* 2088 * The module code should have filled out the item correctly by this stage: 2089 * Common: 2090 * reference to destination node. 2091 * Reference to destination rcv hook if relevant. 2092 * Data: 2093 * pointer to mbuf 2094 * pointer to metadata 2095 * Control_Message: 2096 * pointer to msg. 2097 * ID of original sender node. (return address) 2098 * Function: 2099 * Function pointer 2100 * void * argument 2101 * integer argument 2102 * 2103 * The nodes have several routines and macros to help with this task: 2104 */ 2105 2106 int 2107 ng_snd_item(item_p item, int queue) 2108 { 2109 hook_p hook = NGI_HOOK(item); 2110 node_p node = NGI_NODE(item); 2111 int rw; 2112 int error = 0, ierror; 2113 item_p oitem; 2114 struct ng_queue * ngq = &node->nd_input_queue; 2115 2116 #ifdef NETGRAPH_DEBUG 2117 _ngi_check(item, __FILE__, __LINE__); 2118 #endif 2119 2120 if (item == NULL) { 2121 TRAP_ERROR(); 2122 return (EINVAL); /* failed to get queue element */ 2123 } 2124 if (node == NULL) { 2125 NG_FREE_ITEM(item); 2126 TRAP_ERROR(); 2127 return (EINVAL); /* No address */ 2128 } 2129 switch(item->el_flags & NGQF_TYPE) { 2130 case NGQF_DATA: 2131 /* 2132 * DATA MESSAGE 2133 * Delivered to a node via a non-optional hook. 2134 * Both should be present in the item even though 2135 * the node is derivable from the hook. 2136 * References are held on both by the item. 2137 */ 2138 CHECK_DATA_MBUF(NGI_M(item)); 2139 if (hook == NULL) { 2140 NG_FREE_ITEM(item); 2141 TRAP_ERROR(); 2142 return(EINVAL); 2143 } 2144 if ((NG_HOOK_NOT_VALID(hook)) 2145 || (NG_NODE_NOT_VALID(NG_HOOK_NODE(hook)))) { 2146 NG_FREE_ITEM(item); 2147 return (ENOTCONN); 2148 } 2149 if ((hook->hk_flags & HK_QUEUE)) { 2150 queue = 1; 2151 } 2152 /* By default data is a reader in the locking scheme */ 2153 item->el_flags |= NGQF_READER; 2154 rw = NGQRW_R; 2155 break; 2156 case NGQF_MESG: 2157 /* 2158 * CONTROL MESSAGE 2159 * Delivered to a node. 2160 * Hook is optional. 2161 * References are held by the item on the node and 2162 * the hook if it is present. 2163 */ 2164 if (hook && (hook->hk_flags & HK_QUEUE)) { 2165 queue = 1; 2166 } 2167 /* Data messages count as writers unles explicitly exempted */ 2168 if (NGI_MSG(item)->header.cmd & NGM_READONLY) { 2169 item->el_flags |= NGQF_READER; 2170 rw = NGQRW_R; 2171 } else { 2172 item->el_flags &= ~NGQF_RW; 2173 rw = NGQRW_W; 2174 } 2175 break; 2176 case NGQF_FN: 2177 item->el_flags &= ~NGQF_RW; 2178 rw = NGQRW_W; 2179 break; 2180 default: 2181 NG_FREE_ITEM(item); 2182 TRAP_ERROR(); 2183 return (EINVAL); 2184 } 2185 /* 2186 * If the node specifies single threading, force writer semantics 2187 * Similarly the node may say one hook always produces writers. 2188 * These are over-rides. 2189 */ 2190 if ((node->nd_flags & NG_FORCE_WRITER) 2191 || (hook && (hook->hk_flags & HK_FORCE_WRITER))) { 2192 rw = NGQRW_W; 2193 item->el_flags &= ~NGQF_READER; 2194 } 2195 if (queue) { 2196 /* Put it on the queue for that node*/ 2197 #ifdef NETGRAPH_DEBUG 2198 _ngi_check(item, __FILE__, __LINE__); 2199 #endif 2200 mtx_lock_spin(&(ngq->q_mtx)); 2201 ng_queue_rw(ngq, item, rw); 2202 /* 2203 * If there are active elements then we can rely on 2204 * them. if not we should not rely on another packet 2205 * coming here by another path, 2206 * so it is best to put us in the netisr list. 2207 * We can take the worklist lock with the node locked 2208 * BUT NOT THE REVERSE! 2209 */ 2210 if (CAN_GET_WORK(ngq->q_flags)) { 2211 ng_setisr(node); 2212 } 2213 mtx_unlock_spin(&(ngq->q_mtx)); 2214 return (0); 2215 } 2216 /* 2217 * Take a queue item and a node and see if we can apply the item to 2218 * the node. We may end up getting a different item to apply instead. 2219 * Will allow for a piggyback reply only in the case where 2220 * there is no queueing. 2221 */ 2222 2223 oitem = item; 2224 /* 2225 * We already decided how we will be queueud or treated. 2226 * Try get the appropriate operating permission. 2227 */ 2228 if (rw == NGQRW_R) { 2229 item = ng_acquire_read(ngq, item); 2230 } else { 2231 item = ng_acquire_write(ngq, item); 2232 } 2233 2234 /* 2235 * May have come back with a different item. 2236 * or maybe none at all. The one we started with will 2237 * have been queued in thises cases. 2238 */ 2239 if (item == NULL) { 2240 return (0); 2241 } 2242 2243 #ifdef NETGRAPH_DEBUG 2244 _ngi_check(item, __FILE__, __LINE__); 2245 #endif 2246 /* 2247 * Take over the reference frm the item. 2248 * Hold it until the called function returns. 2249 */ 2250 NGI_GET_NODE(item, node); /* zaps stored node */ 2251 2252 ierror = ng_apply_item(node, item); /* drops r/w lock when done */ 2253 2254 /* only return an error if it was our initial item.. (compat hack) */ 2255 if (oitem == item) { 2256 error = ierror; 2257 } 2258 2259 /* 2260 * If the node goes away when we remove the reference, 2261 * whatever we just did caused it.. whatever we do, DO NOT 2262 * access the node again! 2263 */ 2264 if (NG_NODE_UNREF(node) == 0) { 2265 return (error); 2266 } 2267 2268 /* 2269 * Now we've handled the packet we brought, (or a friend of it) let's 2270 * look for any other packets that may have been queued up. We hold 2271 * no locks, so if someone puts something in the queue after 2272 * we check that it is empty, it is their problem 2273 * to ensure it is processed. If we have the netisr thread cme in here 2274 * while we still say we have stuff to do, we may get a boost 2275 * in SMP systems. :-) 2276 */ 2277 for (;;) { 2278 /* 2279 * dequeue acquires and adjusts the input_queue as it dequeues 2280 * packets. It acquires the rw lock as needed. 2281 */ 2282 mtx_lock_spin(&ngq->q_mtx); 2283 item = ng_dequeue(ngq); /* fixes worklist too*/ 2284 if (!item) { 2285 mtx_unlock_spin(&ngq->q_mtx); 2286 return (error); 2287 } 2288 mtx_unlock_spin(&ngq->q_mtx); 2289 2290 /* 2291 * Take over the reference frm the item. 2292 * Hold it until the called function returns. 2293 */ 2294 2295 NGI_GET_NODE(item, node); /* zaps stored node */ 2296 2297 /* 2298 * We have the appropriate lock, so run the item. 2299 * When finished it will drop the lock accordingly 2300 */ 2301 ierror = ng_apply_item(node, item); 2302 2303 /* 2304 * only return an error if it was our initial 2305 * item.. (compat hack) 2306 */ 2307 if (oitem == item) { 2308 error = ierror; 2309 } 2310 2311 /* 2312 * If the node goes away when we remove the reference, 2313 * whatever we just did caused it.. whatever we do, DO NOT 2314 * access the node again! 2315 */ 2316 if (NG_NODE_UNREF(node) == 0) { 2317 break; 2318 } 2319 } 2320 return (error); 2321 } 2322 2323 /* 2324 * We have an item that was possibly queued somewhere. 2325 * It should contain all the information needed 2326 * to run it on the appropriate node/hook. 2327 */ 2328 static int 2329 ng_apply_item(node_p node, item_p item) 2330 { 2331 hook_p hook; 2332 int was_reader = ((item->el_flags & NGQF_RW)); 2333 int error = 0; 2334 ng_rcvdata_t *rcvdata; 2335 ng_rcvmsg_t *rcvmsg; 2336 2337 NGI_GET_HOOK(item, hook); /* clears stored hook */ 2338 #ifdef NETGRAPH_DEBUG 2339 _ngi_check(item, __FILE__, __LINE__); 2340 #endif 2341 switch (item->el_flags & NGQF_TYPE) { 2342 case NGQF_DATA: 2343 /* 2344 * Check things are still ok as when we were queued. 2345 */ 2346 if ((hook == NULL) 2347 || NG_HOOK_NOT_VALID(hook) 2348 || NG_NODE_NOT_VALID(node) ) { 2349 error = EIO; 2350 NG_FREE_ITEM(item); 2351 break; 2352 } 2353 /* 2354 * If no receive method, just silently drop it. 2355 * Give preference to the hook over-ride method 2356 */ 2357 if ((!(rcvdata = hook->hk_rcvdata)) 2358 && (!(rcvdata = NG_HOOK_NODE(hook)->nd_type->rcvdata))) { 2359 error = 0; 2360 NG_FREE_ITEM(item); 2361 break; 2362 } 2363 error = (*rcvdata)(hook, item); 2364 break; 2365 case NGQF_MESG: 2366 if (hook) { 2367 if (NG_HOOK_NOT_VALID(hook)) { 2368 /* 2369 * The hook has been zapped then we can't 2370 * use it. Immediatly drop its reference. 2371 * The message may not need it. 2372 */ 2373 NG_HOOK_UNREF(hook); 2374 hook = NULL; 2375 } 2376 } 2377 /* 2378 * Similarly, if the node is a zombie there is 2379 * nothing we can do with it, drop everything. 2380 */ 2381 if (NG_NODE_NOT_VALID(node)) { 2382 TRAP_ERROR(); 2383 error = EINVAL; 2384 NG_FREE_ITEM(item); 2385 } else { 2386 /* 2387 * Call the appropriate message handler for the object. 2388 * It is up to the message handler to free the message. 2389 * If it's a generic message, handle it generically, 2390 * otherwise call the type's message handler 2391 * (if it exists) 2392 * XXX (race). Remember that a queued message may 2393 * reference a node or hook that has just been 2394 * invalidated. It will exist as the queue code 2395 * is holding a reference, but.. 2396 */ 2397 2398 struct ng_mesg *msg = NGI_MSG(item); 2399 2400 /* 2401 * check if the generic handler owns it. 2402 */ 2403 if ((msg->header.typecookie == NGM_GENERIC_COOKIE) 2404 && ((msg->header.flags & NGF_RESP) == 0)) { 2405 error = ng_generic_msg(node, item, hook); 2406 break; 2407 } 2408 /* 2409 * Now see if there is a handler (hook or node specific) 2410 * in the target node. If none, silently discard. 2411 */ 2412 if (((!hook) || (!(rcvmsg = hook->hk_rcvmsg))) 2413 && (!(rcvmsg = node->nd_type->rcvmsg))) { 2414 TRAP_ERROR(); 2415 error = 0; 2416 NG_FREE_ITEM(item); 2417 break; 2418 } 2419 error = (*rcvmsg)(node, item, hook); 2420 } 2421 break; 2422 case NGQF_FN: 2423 /* 2424 * We have to implicitly trust the hook, 2425 * as some of these are used for system purposes 2426 * where the hook is invalid. In the case of 2427 * the shutdown message we allow it to hit 2428 * even if the node is invalid. 2429 */ 2430 if ((NG_NODE_NOT_VALID(node)) 2431 && (NGI_FN(item) != &ng_rmnode)) { 2432 TRAP_ERROR(); 2433 error = EINVAL; 2434 break; 2435 } 2436 (*NGI_FN(item))(node, hook, NGI_ARG1(item), NGI_ARG2(item)); 2437 NG_FREE_ITEM(item); 2438 break; 2439 2440 } 2441 /* 2442 * We held references on some of the resources 2443 * that we took from the item. Now that we have 2444 * finished doing everything, drop those references. 2445 */ 2446 if (hook) { 2447 NG_HOOK_UNREF(hook); 2448 } 2449 2450 if (was_reader) { 2451 ng_leave_read(&node->nd_input_queue); 2452 } else { 2453 ng_leave_write(&node->nd_input_queue); 2454 } 2455 return (error); 2456 } 2457 2458 /*********************************************************************** 2459 * Implement the 'generic' control messages 2460 ***********************************************************************/ 2461 static int 2462 ng_generic_msg(node_p here, item_p item, hook_p lasthook) 2463 { 2464 int error = 0; 2465 struct ng_mesg *msg; 2466 struct ng_mesg *resp = NULL; 2467 2468 NGI_GET_MSG(item, msg); 2469 if (msg->header.typecookie != NGM_GENERIC_COOKIE) { 2470 TRAP_ERROR(); 2471 error = EINVAL; 2472 goto out; 2473 } 2474 switch (msg->header.cmd) { 2475 case NGM_SHUTDOWN: 2476 ng_rmnode(here, NULL, NULL, 0); 2477 break; 2478 case NGM_MKPEER: 2479 { 2480 struct ngm_mkpeer *const mkp = (struct ngm_mkpeer *) msg->data; 2481 2482 if (msg->header.arglen != sizeof(*mkp)) { 2483 TRAP_ERROR(); 2484 error = EINVAL; 2485 break; 2486 } 2487 mkp->type[sizeof(mkp->type) - 1] = '\0'; 2488 mkp->ourhook[sizeof(mkp->ourhook) - 1] = '\0'; 2489 mkp->peerhook[sizeof(mkp->peerhook) - 1] = '\0'; 2490 error = ng_mkpeer(here, mkp->ourhook, mkp->peerhook, mkp->type); 2491 break; 2492 } 2493 case NGM_CONNECT: 2494 { 2495 struct ngm_connect *const con = 2496 (struct ngm_connect *) msg->data; 2497 node_p node2; 2498 2499 if (msg->header.arglen != sizeof(*con)) { 2500 TRAP_ERROR(); 2501 error = EINVAL; 2502 break; 2503 } 2504 con->path[sizeof(con->path) - 1] = '\0'; 2505 con->ourhook[sizeof(con->ourhook) - 1] = '\0'; 2506 con->peerhook[sizeof(con->peerhook) - 1] = '\0'; 2507 /* Don't forget we get a reference.. */ 2508 error = ng_path2noderef(here, con->path, &node2, NULL); 2509 if (error) 2510 break; 2511 error = ng_con_nodes(here, con->ourhook, node2, con->peerhook); 2512 NG_NODE_UNREF(node2); 2513 break; 2514 } 2515 case NGM_NAME: 2516 { 2517 struct ngm_name *const nam = (struct ngm_name *) msg->data; 2518 2519 if (msg->header.arglen != sizeof(*nam)) { 2520 TRAP_ERROR(); 2521 error = EINVAL; 2522 break; 2523 } 2524 nam->name[sizeof(nam->name) - 1] = '\0'; 2525 error = ng_name_node(here, nam->name); 2526 break; 2527 } 2528 case NGM_RMHOOK: 2529 { 2530 struct ngm_rmhook *const rmh = (struct ngm_rmhook *) msg->data; 2531 hook_p hook; 2532 2533 if (msg->header.arglen != sizeof(*rmh)) { 2534 TRAP_ERROR(); 2535 error = EINVAL; 2536 break; 2537 } 2538 rmh->ourhook[sizeof(rmh->ourhook) - 1] = '\0'; 2539 if ((hook = ng_findhook(here, rmh->ourhook)) != NULL) 2540 ng_destroy_hook(hook); 2541 break; 2542 } 2543 case NGM_NODEINFO: 2544 { 2545 struct nodeinfo *ni; 2546 2547 NG_MKRESPONSE(resp, msg, sizeof(*ni), M_NOWAIT); 2548 if (resp == NULL) { 2549 error = ENOMEM; 2550 break; 2551 } 2552 2553 /* Fill in node info */ 2554 ni = (struct nodeinfo *) resp->data; 2555 if (NG_NODE_HAS_NAME(here)) 2556 strcpy(ni->name, NG_NODE_NAME(here)); 2557 strcpy(ni->type, here->nd_type->name); 2558 ni->id = ng_node2ID(here); 2559 ni->hooks = here->nd_numhooks; 2560 break; 2561 } 2562 case NGM_LISTHOOKS: 2563 { 2564 const int nhooks = here->nd_numhooks; 2565 struct hooklist *hl; 2566 struct nodeinfo *ni; 2567 hook_p hook; 2568 2569 /* Get response struct */ 2570 NG_MKRESPONSE(resp, msg, sizeof(*hl) 2571 + (nhooks * sizeof(struct linkinfo)), M_NOWAIT); 2572 if (resp == NULL) { 2573 error = ENOMEM; 2574 break; 2575 } 2576 hl = (struct hooklist *) resp->data; 2577 ni = &hl->nodeinfo; 2578 2579 /* Fill in node info */ 2580 if (NG_NODE_HAS_NAME(here)) 2581 strcpy(ni->name, NG_NODE_NAME(here)); 2582 strcpy(ni->type, here->nd_type->name); 2583 ni->id = ng_node2ID(here); 2584 2585 /* Cycle through the linked list of hooks */ 2586 ni->hooks = 0; 2587 LIST_FOREACH(hook, &here->nd_hooks, hk_hooks) { 2588 struct linkinfo *const link = &hl->link[ni->hooks]; 2589 2590 if (ni->hooks >= nhooks) { 2591 log(LOG_ERR, "%s: number of %s changed\n", 2592 __func__, "hooks"); 2593 break; 2594 } 2595 if (NG_HOOK_NOT_VALID(hook)) 2596 continue; 2597 strcpy(link->ourhook, NG_HOOK_NAME(hook)); 2598 strcpy(link->peerhook, NG_PEER_HOOK_NAME(hook)); 2599 if (NG_PEER_NODE_NAME(hook)[0] != '\0') 2600 strcpy(link->nodeinfo.name, 2601 NG_PEER_NODE_NAME(hook)); 2602 strcpy(link->nodeinfo.type, 2603 NG_PEER_NODE(hook)->nd_type->name); 2604 link->nodeinfo.id = ng_node2ID(NG_PEER_NODE(hook)); 2605 link->nodeinfo.hooks = NG_PEER_NODE(hook)->nd_numhooks; 2606 ni->hooks++; 2607 } 2608 break; 2609 } 2610 2611 case NGM_LISTNAMES: 2612 case NGM_LISTNODES: 2613 { 2614 const int unnamed = (msg->header.cmd == NGM_LISTNODES); 2615 struct namelist *nl; 2616 node_p node; 2617 int num = 0; 2618 2619 mtx_lock(&ng_nodelist_mtx); 2620 /* Count number of nodes */ 2621 LIST_FOREACH(node, &ng_nodelist, nd_nodes) { 2622 if (NG_NODE_IS_VALID(node) 2623 && (unnamed || NG_NODE_HAS_NAME(node))) { 2624 num++; 2625 } 2626 } 2627 mtx_unlock(&ng_nodelist_mtx); 2628 2629 /* Get response struct */ 2630 NG_MKRESPONSE(resp, msg, sizeof(*nl) 2631 + (num * sizeof(struct nodeinfo)), M_NOWAIT); 2632 if (resp == NULL) { 2633 error = ENOMEM; 2634 break; 2635 } 2636 nl = (struct namelist *) resp->data; 2637 2638 /* Cycle through the linked list of nodes */ 2639 nl->numnames = 0; 2640 mtx_lock(&ng_nodelist_mtx); 2641 LIST_FOREACH(node, &ng_nodelist, nd_nodes) { 2642 struct nodeinfo *const np = &nl->nodeinfo[nl->numnames]; 2643 2644 if (nl->numnames >= num) { 2645 log(LOG_ERR, "%s: number of %s changed\n", 2646 __func__, "nodes"); 2647 break; 2648 } 2649 if (NG_NODE_NOT_VALID(node)) 2650 continue; 2651 if (!unnamed && (! NG_NODE_HAS_NAME(node))) 2652 continue; 2653 if (NG_NODE_HAS_NAME(node)) 2654 strcpy(np->name, NG_NODE_NAME(node)); 2655 strcpy(np->type, node->nd_type->name); 2656 np->id = ng_node2ID(node); 2657 np->hooks = node->nd_numhooks; 2658 nl->numnames++; 2659 } 2660 mtx_unlock(&ng_nodelist_mtx); 2661 break; 2662 } 2663 2664 case NGM_LISTTYPES: 2665 { 2666 struct typelist *tl; 2667 struct ng_type *type; 2668 int num = 0; 2669 2670 mtx_lock(&ng_typelist_mtx); 2671 /* Count number of types */ 2672 LIST_FOREACH(type, &ng_typelist, types) { 2673 num++; 2674 } 2675 mtx_unlock(&ng_typelist_mtx); 2676 2677 /* Get response struct */ 2678 NG_MKRESPONSE(resp, msg, sizeof(*tl) 2679 + (num * sizeof(struct typeinfo)), M_NOWAIT); 2680 if (resp == NULL) { 2681 error = ENOMEM; 2682 break; 2683 } 2684 tl = (struct typelist *) resp->data; 2685 2686 /* Cycle through the linked list of types */ 2687 tl->numtypes = 0; 2688 mtx_lock(&ng_typelist_mtx); 2689 LIST_FOREACH(type, &ng_typelist, types) { 2690 struct typeinfo *const tp = &tl->typeinfo[tl->numtypes]; 2691 2692 if (tl->numtypes >= num) { 2693 log(LOG_ERR, "%s: number of %s changed\n", 2694 __func__, "types"); 2695 break; 2696 } 2697 strcpy(tp->type_name, type->name); 2698 tp->numnodes = type->refs - 1; /* don't count list */ 2699 tl->numtypes++; 2700 } 2701 mtx_unlock(&ng_typelist_mtx); 2702 break; 2703 } 2704 2705 case NGM_BINARY2ASCII: 2706 { 2707 int bufSize = 20 * 1024; /* XXX hard coded constant */ 2708 const struct ng_parse_type *argstype; 2709 const struct ng_cmdlist *c; 2710 struct ng_mesg *binary, *ascii; 2711 2712 /* Data area must contain a valid netgraph message */ 2713 binary = (struct ng_mesg *)msg->data; 2714 if (msg->header.arglen < sizeof(struct ng_mesg) 2715 || (msg->header.arglen - sizeof(struct ng_mesg) 2716 < binary->header.arglen)) { 2717 TRAP_ERROR(); 2718 error = EINVAL; 2719 break; 2720 } 2721 2722 /* Get a response message with lots of room */ 2723 NG_MKRESPONSE(resp, msg, sizeof(*ascii) + bufSize, M_NOWAIT); 2724 if (resp == NULL) { 2725 error = ENOMEM; 2726 break; 2727 } 2728 ascii = (struct ng_mesg *)resp->data; 2729 2730 /* Copy binary message header to response message payload */ 2731 bcopy(binary, ascii, sizeof(*binary)); 2732 2733 /* Find command by matching typecookie and command number */ 2734 for (c = here->nd_type->cmdlist; 2735 c != NULL && c->name != NULL; c++) { 2736 if (binary->header.typecookie == c->cookie 2737 && binary->header.cmd == c->cmd) 2738 break; 2739 } 2740 if (c == NULL || c->name == NULL) { 2741 for (c = ng_generic_cmds; c->name != NULL; c++) { 2742 if (binary->header.typecookie == c->cookie 2743 && binary->header.cmd == c->cmd) 2744 break; 2745 } 2746 if (c->name == NULL) { 2747 NG_FREE_MSG(resp); 2748 error = ENOSYS; 2749 break; 2750 } 2751 } 2752 2753 /* Convert command name to ASCII */ 2754 snprintf(ascii->header.cmdstr, sizeof(ascii->header.cmdstr), 2755 "%s", c->name); 2756 2757 /* Convert command arguments to ASCII */ 2758 argstype = (binary->header.flags & NGF_RESP) ? 2759 c->respType : c->mesgType; 2760 if (argstype == NULL) { 2761 *ascii->data = '\0'; 2762 } else { 2763 if ((error = ng_unparse(argstype, 2764 (u_char *)binary->data, 2765 ascii->data, bufSize)) != 0) { 2766 NG_FREE_MSG(resp); 2767 break; 2768 } 2769 } 2770 2771 /* Return the result as struct ng_mesg plus ASCII string */ 2772 bufSize = strlen(ascii->data) + 1; 2773 ascii->header.arglen = bufSize; 2774 resp->header.arglen = sizeof(*ascii) + bufSize; 2775 break; 2776 } 2777 2778 case NGM_ASCII2BINARY: 2779 { 2780 int bufSize = 2000; /* XXX hard coded constant */ 2781 const struct ng_cmdlist *c; 2782 const struct ng_parse_type *argstype; 2783 struct ng_mesg *ascii, *binary; 2784 int off = 0; 2785 2786 /* Data area must contain at least a struct ng_mesg + '\0' */ 2787 ascii = (struct ng_mesg *)msg->data; 2788 if ((msg->header.arglen < sizeof(*ascii) + 1) 2789 || (ascii->header.arglen < 1) 2790 || (msg->header.arglen 2791 < sizeof(*ascii) + ascii->header.arglen)) { 2792 TRAP_ERROR(); 2793 error = EINVAL; 2794 break; 2795 } 2796 ascii->data[ascii->header.arglen - 1] = '\0'; 2797 2798 /* Get a response message with lots of room */ 2799 NG_MKRESPONSE(resp, msg, sizeof(*binary) + bufSize, M_NOWAIT); 2800 if (resp == NULL) { 2801 error = ENOMEM; 2802 break; 2803 } 2804 binary = (struct ng_mesg *)resp->data; 2805 2806 /* Copy ASCII message header to response message payload */ 2807 bcopy(ascii, binary, sizeof(*ascii)); 2808 2809 /* Find command by matching ASCII command string */ 2810 for (c = here->nd_type->cmdlist; 2811 c != NULL && c->name != NULL; c++) { 2812 if (strcmp(ascii->header.cmdstr, c->name) == 0) 2813 break; 2814 } 2815 if (c == NULL || c->name == NULL) { 2816 for (c = ng_generic_cmds; c->name != NULL; c++) { 2817 if (strcmp(ascii->header.cmdstr, c->name) == 0) 2818 break; 2819 } 2820 if (c->name == NULL) { 2821 NG_FREE_MSG(resp); 2822 error = ENOSYS; 2823 break; 2824 } 2825 } 2826 2827 /* Convert command name to binary */ 2828 binary->header.cmd = c->cmd; 2829 binary->header.typecookie = c->cookie; 2830 2831 /* Convert command arguments to binary */ 2832 argstype = (binary->header.flags & NGF_RESP) ? 2833 c->respType : c->mesgType; 2834 if (argstype == NULL) { 2835 bufSize = 0; 2836 } else { 2837 if ((error = ng_parse(argstype, ascii->data, 2838 &off, (u_char *)binary->data, &bufSize)) != 0) { 2839 NG_FREE_MSG(resp); 2840 break; 2841 } 2842 } 2843 2844 /* Return the result */ 2845 binary->header.arglen = bufSize; 2846 resp->header.arglen = sizeof(*binary) + bufSize; 2847 break; 2848 } 2849 2850 case NGM_TEXT_CONFIG: 2851 case NGM_TEXT_STATUS: 2852 /* 2853 * This one is tricky as it passes the command down to the 2854 * actual node, even though it is a generic type command. 2855 * This means we must assume that the item/msg is already freed 2856 * when control passes back to us. 2857 */ 2858 if (here->nd_type->rcvmsg != NULL) { 2859 NGI_MSG(item) = msg; /* put it back as we found it */ 2860 return((*here->nd_type->rcvmsg)(here, item, lasthook)); 2861 } 2862 /* Fall through if rcvmsg not supported */ 2863 default: 2864 TRAP_ERROR(); 2865 error = EINVAL; 2866 } 2867 /* 2868 * Sometimes a generic message may be statically allocated 2869 * to avoid problems with allocating when in tight memeory situations. 2870 * Don't free it if it is so. 2871 * I break them appart here, because erros may cause a free if the item 2872 * in which case we'd be doing it twice. 2873 * they are kept together above, to simplify freeing. 2874 */ 2875 out: 2876 NG_RESPOND_MSG(error, here, item, resp); 2877 if (msg) 2878 NG_FREE_MSG(msg); 2879 return (error); 2880 } 2881 2882 /* 2883 * Copy a 'meta'. 2884 * 2885 * Returns new meta, or NULL if original meta is NULL or ENOMEM. 2886 */ 2887 meta_p 2888 ng_copy_meta(meta_p meta) 2889 { 2890 meta_p meta2; 2891 2892 if (meta == NULL) 2893 return (NULL); 2894 MALLOC(meta2, meta_p, meta->used_len, M_NETGRAPH_META, M_NOWAIT); 2895 if (meta2 == NULL) 2896 return (NULL); 2897 meta2->allocated_len = meta->used_len; 2898 bcopy(meta, meta2, meta->used_len); 2899 return (meta2); 2900 } 2901 2902 /************************************************************************ 2903 Module routines 2904 ************************************************************************/ 2905 2906 /* 2907 * Handle the loading/unloading of a netgraph node type module 2908 */ 2909 int 2910 ng_mod_event(module_t mod, int event, void *data) 2911 { 2912 struct ng_type *const type = data; 2913 int s, error = 0; 2914 2915 switch (event) { 2916 case MOD_LOAD: 2917 2918 /* Register new netgraph node type */ 2919 s = splnet(); 2920 if ((error = ng_newtype(type)) != 0) { 2921 splx(s); 2922 break; 2923 } 2924 2925 /* Call type specific code */ 2926 if (type->mod_event != NULL) 2927 if ((error = (*type->mod_event)(mod, event, data))) { 2928 mtx_lock(&ng_typelist_mtx); 2929 type->refs--; /* undo it */ 2930 LIST_REMOVE(type, types); 2931 mtx_unlock(&ng_typelist_mtx); 2932 } 2933 splx(s); 2934 break; 2935 2936 case MOD_UNLOAD: 2937 s = splnet(); 2938 if (type->refs > 1) { /* make sure no nodes exist! */ 2939 error = EBUSY; 2940 } else { 2941 if (type->refs == 0) { 2942 /* failed load, nothing to undo */ 2943 splx(s); 2944 break; 2945 } 2946 if (type->mod_event != NULL) { /* check with type */ 2947 error = (*type->mod_event)(mod, event, data); 2948 if (error != 0) { /* type refuses.. */ 2949 splx(s); 2950 break; 2951 } 2952 } 2953 mtx_lock(&ng_typelist_mtx); 2954 LIST_REMOVE(type, types); 2955 mtx_unlock(&ng_typelist_mtx); 2956 } 2957 splx(s); 2958 break; 2959 2960 default: 2961 if (type->mod_event != NULL) 2962 error = (*type->mod_event)(mod, event, data); 2963 else 2964 error = 0; /* XXX ? */ 2965 break; 2966 } 2967 return (error); 2968 } 2969 2970 /* 2971 * Handle loading and unloading for this code. 2972 * The only thing we need to link into is the NETISR strucure. 2973 */ 2974 static int 2975 ngb_mod_event(module_t mod, int event, void *data) 2976 { 2977 int s, error = 0; 2978 2979 switch (event) { 2980 case MOD_LOAD: 2981 /* Register line discipline */ 2982 mtx_init(&ng_worklist_mtx, "ng_worklist", NULL, MTX_SPIN); 2983 mtx_init(&ng_typelist_mtx, "netgraph types mutex", NULL, 2984 MTX_DEF); 2985 mtx_init(&ng_nodelist_mtx, "netgraph nodelist mutex", NULL, 2986 MTX_DEF); 2987 mtx_init(&ng_idhash_mtx, "netgraph idhash mutex", NULL, 2988 MTX_DEF); 2989 mtx_init(&ngq_mtx, "netgraph free item list mutex", NULL, 2990 MTX_DEF); 2991 s = splimp(); 2992 /* XXX could use NETISR_MPSAFE but need to verify code */ 2993 netisr_register(NETISR_NETGRAPH, (netisr_t *)ngintr, NULL, 0); 2994 splx(s); 2995 break; 2996 case MOD_UNLOAD: 2997 /* You cant unload it because an interface may be using it. */ 2998 error = EBUSY; 2999 break; 3000 default: 3001 error = EOPNOTSUPP; 3002 break; 3003 } 3004 return (error); 3005 } 3006 3007 static moduledata_t netgraph_mod = { 3008 "netgraph", 3009 ngb_mod_event, 3010 (NULL) 3011 }; 3012 DECLARE_MODULE(netgraph, netgraph_mod, SI_SUB_DRIVERS, SI_ORDER_MIDDLE); 3013 SYSCTL_NODE(_net, OID_AUTO, graph, CTLFLAG_RW, 0, "netgraph Family"); 3014 SYSCTL_INT(_net_graph, OID_AUTO, abi_version, CTLFLAG_RD, 0, NG_ABI_VERSION,""); 3015 SYSCTL_INT(_net_graph, OID_AUTO, msg_version, CTLFLAG_RD, 0, NG_VERSION, ""); 3016 3017 /************************************************************************ 3018 Queue element get/free routines 3019 ************************************************************************/ 3020 3021 3022 static int allocated; /* number of items malloc'd */ 3023 3024 static int maxalloc = 128; /* limit the damage of a leak */ 3025 static int ngqfreemax = 64;/* cache at most this many */ 3026 3027 TUNABLE_INT("net.graph.maxalloc", &maxalloc); 3028 SYSCTL_INT(_net_graph, OID_AUTO, maxalloc, CTLFLAG_RDTUN, &maxalloc, 3029 0, "Maximum number of queue items to allocate"); 3030 3031 TUNABLE_INT("net.graph.ngqfreemax", &ngqfreemax); 3032 SYSCTL_INT(_net_graph, OID_AUTO, ngqfreemax, CTLFLAG_RDTUN, &ngqfreemax, 3033 0, "Maximum number of free queue items to cache"); 3034 3035 static const int ngqfreelow = 4; /* try malloc if free < this */ 3036 static volatile int ngqfreesize; /* number of cached entries */ 3037 static volatile item_p ngqfree; /* free ones */ 3038 3039 #ifdef NETGRAPH_DEBUG 3040 static TAILQ_HEAD(, ng_item) ng_itemlist = TAILQ_HEAD_INITIALIZER(ng_itemlist); 3041 #endif 3042 /* 3043 * Get a queue entry 3044 * This is usually called when a packet first enters netgraph. 3045 * By definition, this is usually from an interrupt, or from a user. 3046 * Users are not so important, but try be quick for the times that it's 3047 * an interrupt. 3048 * XXX If reserve is low, we should try to get 2 from malloc as this 3049 * would indicate it often fails. 3050 */ 3051 static item_p 3052 ng_getqblk(void) 3053 { 3054 item_p item = NULL; 3055 3056 /* 3057 * Try get a cached queue block, or else allocate a new one 3058 * If we are less than our reserve, try malloc. If malloc 3059 * fails, then that's what the reserve is for... 3060 * We have our little reserve 3061 * because we use M_NOWAIT for malloc. This just helps us 3062 * avoid dropping packets while not increasing the time 3063 * we take to service the interrupt (on average) (I hope). 3064 */ 3065 mtx_lock(&ngq_mtx); 3066 3067 if ((ngqfreesize < ngqfreelow) || (ngqfree == NULL)) { 3068 if (allocated < maxalloc) { /* don't leak forever */ 3069 MALLOC(item, item_p , 3070 sizeof(*item), M_NETGRAPH_ITEM, 3071 (M_NOWAIT | M_ZERO)); 3072 if (item) { 3073 #ifdef NETGRAPH_DEBUG 3074 TAILQ_INSERT_TAIL(&ng_itemlist, item, all); 3075 #endif /* NETGRAPH_DEBUG */ 3076 allocated++; 3077 } 3078 } 3079 } 3080 3081 /* 3082 * We didn't or couldn't malloc. 3083 * try get one from our cache. 3084 */ 3085 if (item == NULL && (item = ngqfree) != NULL) { 3086 ngqfree = item->el_next; 3087 ngqfreesize--; 3088 item->el_flags &= ~NGQF_FREE; 3089 } 3090 3091 mtx_unlock(&ngq_mtx); 3092 return (item); 3093 } 3094 3095 /* 3096 * Release a queue entry 3097 */ 3098 void 3099 ng_free_item(item_p item) 3100 { 3101 3102 /* 3103 * The item may hold resources on it's own. We need to free 3104 * these before we can free the item. What they are depends upon 3105 * what kind of item it is. it is important that nodes zero 3106 * out pointers to resources that they remove from the item 3107 * or we release them again here. 3108 */ 3109 if (item->el_flags & NGQF_FREE) { 3110 panic(" Freeing free queue item"); 3111 } 3112 switch (item->el_flags & NGQF_TYPE) { 3113 case NGQF_DATA: 3114 /* If we have an mbuf and metadata still attached.. */ 3115 NG_FREE_M(_NGI_M(item)); 3116 NG_FREE_META(_NGI_META(item)); 3117 break; 3118 case NGQF_MESG: 3119 _NGI_RETADDR(item) = 0; 3120 NG_FREE_MSG(_NGI_MSG(item)); 3121 break; 3122 case NGQF_FN: 3123 /* nothing to free really, */ 3124 _NGI_FN(item) = NULL; 3125 _NGI_ARG1(item) = NULL; 3126 _NGI_ARG2(item) = 0; 3127 case NGQF_UNDEF: 3128 break; 3129 } 3130 /* If we still have a node or hook referenced... */ 3131 _NGI_CLR_NODE(item); 3132 _NGI_CLR_HOOK(item); 3133 item->el_flags |= NGQF_FREE; 3134 3135 mtx_lock(&ngq_mtx); 3136 if (ngqfreesize < ngqfreemax) { 3137 ngqfreesize++; 3138 item->el_next = ngqfree; 3139 ngqfree = item; 3140 } else { 3141 #ifdef NETGRAPH_DEBUG 3142 TAILQ_REMOVE(&ng_itemlist, item, all); 3143 #endif /* NETGRAPH_DEBUG */ 3144 NG_FREE_ITEM_REAL(item); 3145 allocated--; 3146 } 3147 mtx_unlock(&ngq_mtx); 3148 } 3149 3150 #ifdef NETGRAPH_DEBUG 3151 void 3152 dumphook (hook_p hook, char *file, int line) 3153 { 3154 printf("hook: name %s, %d refs, Last touched:\n", 3155 _NG_HOOK_NAME(hook), hook->hk_refs); 3156 printf(" Last active @ %s, line %d\n", 3157 hook->lastfile, hook->lastline); 3158 if (line) { 3159 printf(" problem discovered at file %s, line %d\n", file, line); 3160 } 3161 } 3162 3163 void 3164 dumpnode(node_p node, char *file, int line) 3165 { 3166 printf("node: ID [%x]: type '%s', %d hooks, flags 0x%x, %d refs, %s:\n", 3167 _NG_NODE_ID(node), node->nd_type->name, 3168 node->nd_numhooks, node->nd_flags, 3169 node->nd_refs, node->nd_name); 3170 printf(" Last active @ %s, line %d\n", 3171 node->lastfile, node->lastline); 3172 if (line) { 3173 printf(" problem discovered at file %s, line %d\n", file, line); 3174 } 3175 } 3176 3177 void 3178 dumpitem(item_p item, char *file, int line) 3179 { 3180 if (item->el_flags & NGQF_FREE) { 3181 printf(" Free item, freed at %s, line %d\n", 3182 item->lastfile, item->lastline); 3183 } else { 3184 printf(" ACTIVE item, last used at %s, line %d", 3185 item->lastfile, item->lastline); 3186 switch(item->el_flags & NGQF_TYPE) { 3187 case NGQF_DATA: 3188 printf(" - [data]\n"); 3189 break; 3190 case NGQF_MESG: 3191 printf(" - retaddr[%d]:\n", _NGI_RETADDR(item)); 3192 break; 3193 case NGQF_FN: 3194 printf(" - fn@%p (%p, %p, %p, %d (%x))\n", 3195 item->body.fn.fn_fn, 3196 NGI_NODE(item), 3197 NGI_HOOK(item), 3198 item->body.fn.fn_arg1, 3199 item->body.fn.fn_arg2, 3200 item->body.fn.fn_arg2); 3201 break; 3202 case NGQF_UNDEF: 3203 printf(" - UNDEFINED!\n"); 3204 } 3205 } 3206 if (line) { 3207 printf(" problem discovered at file %s, line %d\n", file, line); 3208 if (NGI_NODE(item)) { 3209 printf("node %p ([%x])\n", 3210 NGI_NODE(item), ng_node2ID(NGI_NODE(item))); 3211 } 3212 } 3213 } 3214 3215 static void 3216 ng_dumpitems(void) 3217 { 3218 item_p item; 3219 int i = 1; 3220 TAILQ_FOREACH(item, &ng_itemlist, all) { 3221 printf("[%d] ", i++); 3222 dumpitem(item, NULL, 0); 3223 } 3224 } 3225 3226 static void 3227 ng_dumpnodes(void) 3228 { 3229 node_p node; 3230 int i = 1; 3231 SLIST_FOREACH(node, &ng_allnodes, nd_all) { 3232 printf("[%d] ", i++); 3233 dumpnode(node, NULL, 0); 3234 } 3235 } 3236 3237 static void 3238 ng_dumphooks(void) 3239 { 3240 hook_p hook; 3241 int i = 1; 3242 SLIST_FOREACH(hook, &ng_allhooks, hk_all) { 3243 printf("[%d] ", i++); 3244 dumphook(hook, NULL, 0); 3245 } 3246 } 3247 3248 static int 3249 sysctl_debug_ng_dump_items(SYSCTL_HANDLER_ARGS) 3250 { 3251 int error; 3252 int val; 3253 int i; 3254 3255 val = allocated; 3256 i = 1; 3257 error = sysctl_handle_int(oidp, &val, sizeof(int), req); 3258 if (error != 0 || req->newptr == NULL) 3259 return (error); 3260 if (val == 42) { 3261 ng_dumpitems(); 3262 ng_dumpnodes(); 3263 ng_dumphooks(); 3264 } 3265 return (0); 3266 } 3267 3268 SYSCTL_PROC(_debug, OID_AUTO, ng_dump_items, CTLTYPE_INT | CTLFLAG_RW, 3269 0, sizeof(int), sysctl_debug_ng_dump_items, "I", "Number of allocated items"); 3270 #endif /* NETGRAPH_DEBUG */ 3271 3272 3273 /*********************************************************************** 3274 * Worklist routines 3275 **********************************************************************/ 3276 /* NETISR thread enters here */ 3277 /* 3278 * Pick a node off the list of nodes with work, 3279 * try get an item to process off it. 3280 * If there are no more, remove the node from the list. 3281 */ 3282 static void 3283 ngintr(void) 3284 { 3285 item_p item; 3286 node_p node = NULL; 3287 3288 for (;;) { 3289 mtx_lock_spin(&ng_worklist_mtx); 3290 node = TAILQ_FIRST(&ng_worklist); 3291 if (!node) { 3292 mtx_unlock_spin(&ng_worklist_mtx); 3293 break; 3294 } 3295 node->nd_flags &= ~NG_WORKQ; 3296 TAILQ_REMOVE(&ng_worklist, node, nd_work); 3297 mtx_unlock_spin(&ng_worklist_mtx); 3298 /* 3299 * We have the node. We also take over the reference 3300 * that the list had on it. 3301 * Now process as much as you can, until it won't 3302 * let you have another item off the queue. 3303 * All this time, keep the reference 3304 * that lets us be sure that the node still exists. 3305 * Let the reference go at the last minute. 3306 * ng_dequeue will put us back on the worklist 3307 * if there is more too do. This may be of use if there 3308 * are Multiple Processors and multiple Net threads in the 3309 * future. 3310 */ 3311 for (;;) { 3312 mtx_lock_spin(&node->nd_input_queue.q_mtx); 3313 item = ng_dequeue(&node->nd_input_queue); 3314 if (item == NULL) { 3315 mtx_unlock_spin(&node->nd_input_queue.q_mtx); 3316 break; /* go look for another node */ 3317 } else { 3318 mtx_unlock_spin(&node->nd_input_queue.q_mtx); 3319 NGI_GET_NODE(item, node); /* zaps stored node */ 3320 ng_apply_item(node, item); 3321 NG_NODE_UNREF(node); 3322 } 3323 } 3324 NG_NODE_UNREF(node); 3325 } 3326 } 3327 3328 static void 3329 ng_worklist_remove(node_p node) 3330 { 3331 mtx_lock_spin(&ng_worklist_mtx); 3332 if (node->nd_flags & NG_WORKQ) { 3333 node->nd_flags &= ~NG_WORKQ; 3334 TAILQ_REMOVE(&ng_worklist, node, nd_work); 3335 mtx_unlock_spin(&ng_worklist_mtx); 3336 NG_NODE_UNREF(node); 3337 } else { 3338 mtx_unlock_spin(&ng_worklist_mtx); 3339 } 3340 } 3341 3342 /* 3343 * XXX 3344 * It's posible that a debugging NG_NODE_REF may need 3345 * to be outside the mutex zone 3346 */ 3347 static void 3348 ng_setisr(node_p node) 3349 { 3350 mtx_lock_spin(&ng_worklist_mtx); 3351 if ((node->nd_flags & NG_WORKQ) == 0) { 3352 /* 3353 * If we are not already on the work queue, 3354 * then put us on. 3355 */ 3356 node->nd_flags |= NG_WORKQ; 3357 TAILQ_INSERT_TAIL(&ng_worklist, node, nd_work); 3358 NG_NODE_REF(node); /* XXX fafe in mutex? */ 3359 } 3360 mtx_unlock_spin(&ng_worklist_mtx); 3361 schednetisr(NETISR_NETGRAPH); 3362 } 3363 3364 3365 /*********************************************************************** 3366 * Externally useable functions to set up a queue item ready for sending 3367 ***********************************************************************/ 3368 3369 #ifdef NETGRAPH_DEBUG 3370 #define ITEM_DEBUG_CHECKS \ 3371 do { \ 3372 if (NGI_NODE(item) ) { \ 3373 printf("item already has node"); \ 3374 Debugger("has node"); \ 3375 NGI_CLR_NODE(item); \ 3376 } \ 3377 if (NGI_HOOK(item) ) { \ 3378 printf("item already has hook"); \ 3379 Debugger("has hook"); \ 3380 NGI_CLR_HOOK(item); \ 3381 } \ 3382 } while (0) 3383 #else 3384 #define ITEM_DEBUG_CHECKS 3385 #endif 3386 3387 /* 3388 * Put elements into the item. 3389 * Hook and node references will be removed when the item is dequeued. 3390 * (or equivalent) 3391 * (XXX) Unsafe because no reference held by peer on remote node. 3392 * remote node might go away in this timescale. 3393 * We know the hooks can't go away because that would require getting 3394 * a writer item on both nodes and we must have at least a reader 3395 * here to eb able to do this. 3396 * Note that the hook loaded is the REMOTE hook. 3397 * 3398 * This is possibly in the critical path for new data. 3399 */ 3400 item_p 3401 ng_package_data(struct mbuf *m, meta_p meta) 3402 { 3403 item_p item; 3404 3405 if ((item = ng_getqblk()) == NULL) { 3406 NG_FREE_M(m); 3407 NG_FREE_META(meta); 3408 return (NULL); 3409 } 3410 ITEM_DEBUG_CHECKS; 3411 item->el_flags = NGQF_DATA; 3412 item->el_next = NULL; 3413 NGI_M(item) = m; 3414 NGI_META(item) = meta; 3415 return (item); 3416 } 3417 3418 /* 3419 * Allocate a queue item and put items into it.. 3420 * Evaluate the address as this will be needed to queue it and 3421 * to work out what some of the fields should be. 3422 * Hook and node references will be removed when the item is dequeued. 3423 * (or equivalent) 3424 */ 3425 item_p 3426 ng_package_msg(struct ng_mesg *msg) 3427 { 3428 item_p item; 3429 3430 if ((item = ng_getqblk()) == NULL) { 3431 NG_FREE_MSG(msg); 3432 return (NULL); 3433 } 3434 ITEM_DEBUG_CHECKS; 3435 item->el_flags = NGQF_MESG; 3436 item->el_next = NULL; 3437 /* 3438 * Set the current lasthook into the queue item 3439 */ 3440 NGI_MSG(item) = msg; 3441 NGI_RETADDR(item) = 0; 3442 return (item); 3443 } 3444 3445 3446 3447 #define SET_RETADDR(item, here, retaddr) \ 3448 do { /* Data or fn items don't have retaddrs */ \ 3449 if ((item->el_flags & NGQF_TYPE) == NGQF_MESG) { \ 3450 if (retaddr) { \ 3451 NGI_RETADDR(item) = retaddr; \ 3452 } else { \ 3453 /* \ 3454 * The old return address should be ok. \ 3455 * If there isn't one, use the address \ 3456 * here. \ 3457 */ \ 3458 if (NGI_RETADDR(item) == 0) { \ 3459 NGI_RETADDR(item) \ 3460 = ng_node2ID(here); \ 3461 } \ 3462 } \ 3463 } \ 3464 } while (0) 3465 3466 int 3467 ng_address_hook(node_p here, item_p item, hook_p hook, ng_ID_t retaddr) 3468 { 3469 hook_p peer; 3470 node_p peernode; 3471 ITEM_DEBUG_CHECKS; 3472 /* 3473 * Quick sanity check.. 3474 * Since a hook holds a reference on it's node, once we know 3475 * that the peer is still connected (even if invalid,) we know 3476 * that the peer node is present, though maybe invalid. 3477 */ 3478 if ((hook == NULL) 3479 || NG_HOOK_NOT_VALID(hook) 3480 || (NG_HOOK_PEER(hook) == NULL) 3481 || NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook)) 3482 || NG_NODE_NOT_VALID(NG_PEER_NODE(hook))) { 3483 NG_FREE_ITEM(item); 3484 TRAP_ERROR(); 3485 return (ENETDOWN); 3486 } 3487 3488 /* 3489 * Transfer our interest to the other (peer) end. 3490 */ 3491 peer = NG_HOOK_PEER(hook); 3492 NG_HOOK_REF(peer); 3493 NGI_SET_HOOK(item, peer); 3494 peernode = NG_PEER_NODE(hook); 3495 NG_NODE_REF(peernode); 3496 NGI_SET_NODE(item, peernode); 3497 SET_RETADDR(item, here, retaddr); 3498 return (0); 3499 } 3500 3501 int 3502 ng_address_path(node_p here, item_p item, char *address, ng_ID_t retaddr) 3503 { 3504 node_p dest = NULL; 3505 hook_p hook = NULL; 3506 int error; 3507 3508 ITEM_DEBUG_CHECKS; 3509 /* 3510 * Note that ng_path2noderef increments the reference count 3511 * on the node for us if it finds one. So we don't have to. 3512 */ 3513 error = ng_path2noderef(here, address, &dest, &hook); 3514 if (error) { 3515 NG_FREE_ITEM(item); 3516 return (error); 3517 } 3518 NGI_SET_NODE(item, dest); 3519 if ( hook) { 3520 NG_HOOK_REF(hook); /* don't let it go while on the queue */ 3521 NGI_SET_HOOK(item, hook); 3522 } 3523 SET_RETADDR(item, here, retaddr); 3524 return (0); 3525 } 3526 3527 int 3528 ng_address_ID(node_p here, item_p item, ng_ID_t ID, ng_ID_t retaddr) 3529 { 3530 node_p dest; 3531 3532 ITEM_DEBUG_CHECKS; 3533 /* 3534 * Find the target node. 3535 */ 3536 dest = ng_ID2noderef(ID); /* GETS REFERENCE! */ 3537 if (dest == NULL) { 3538 NG_FREE_ITEM(item); 3539 TRAP_ERROR(); 3540 return(EINVAL); 3541 } 3542 /* Fill out the contents */ 3543 item->el_flags = NGQF_MESG; 3544 item->el_next = NULL; 3545 NGI_SET_NODE(item, dest); 3546 NGI_CLR_HOOK(item); 3547 SET_RETADDR(item, here, retaddr); 3548 return (0); 3549 } 3550 3551 /* 3552 * special case to send a message to self (e.g. destroy node) 3553 * Possibly indicate an arrival hook too. 3554 * Useful for removing that hook :-) 3555 */ 3556 item_p 3557 ng_package_msg_self(node_p here, hook_p hook, struct ng_mesg *msg) 3558 { 3559 item_p item; 3560 3561 /* 3562 * Find the target node. 3563 * If there is a HOOK argument, then use that in preference 3564 * to the address. 3565 */ 3566 if ((item = ng_getqblk()) == NULL) { 3567 NG_FREE_MSG(msg); 3568 return (NULL); 3569 } 3570 3571 /* Fill out the contents */ 3572 item->el_flags = NGQF_MESG; 3573 item->el_next = NULL; 3574 NG_NODE_REF(here); 3575 NGI_SET_NODE(item, here); 3576 if (hook) { 3577 NG_HOOK_REF(hook); 3578 NGI_SET_HOOK(item, hook); 3579 } 3580 NGI_MSG(item) = msg; 3581 NGI_RETADDR(item) = ng_node2ID(here); 3582 return (item); 3583 } 3584 3585 int 3586 ng_send_fn(node_p node, hook_p hook, ng_item_fn *fn, void * arg1, int arg2) 3587 { 3588 item_p item; 3589 3590 if ((item = ng_getqblk()) == NULL) { 3591 return (ENOMEM); 3592 } 3593 item->el_flags = NGQF_FN | NGQF_WRITER; 3594 NG_NODE_REF(node); /* and one for the item */ 3595 NGI_SET_NODE(item, node); 3596 if (hook) { 3597 NG_HOOK_REF(hook); 3598 NGI_SET_HOOK(item, hook); 3599 } 3600 NGI_FN(item) = fn; 3601 NGI_ARG1(item) = arg1; 3602 NGI_ARG2(item) = arg2; 3603 return(ng_snd_item(item, 0)); 3604 } 3605 3606 /* 3607 * Official timeout routines for Netgraph nodes. 3608 */ 3609 static void 3610 ng_timeout_trapoline(void *arg) 3611 { 3612 item_p item = arg; 3613 3614 ng_snd_item(item, 0); 3615 } 3616 3617 3618 struct callout_handle 3619 ng_timeout(node_p node, hook_p hook, int ticks, 3620 ng_item_fn *fn, void * arg1, int arg2) 3621 { 3622 item_p item; 3623 3624 if ((item = ng_getqblk()) == NULL) { 3625 struct callout_handle handle; 3626 handle.callout = NULL; 3627 return (handle); 3628 } 3629 item->el_flags = NGQF_FN | NGQF_WRITER; 3630 NG_NODE_REF(node); /* and one for the item */ 3631 NGI_SET_NODE(item, node); 3632 if (hook) { 3633 NG_HOOK_REF(hook); 3634 NGI_SET_HOOK(item, hook); 3635 } 3636 NGI_FN(item) = fn; 3637 NGI_ARG1(item) = arg1; 3638 NGI_ARG2(item) = arg2; 3639 return (timeout(&ng_timeout_trapoline, item, ticks)); 3640 } 3641 3642 /* A special modified version of untimeout() */ 3643 int 3644 ng_untimeout(struct callout_handle handle, node_p node) 3645 { 3646 item_p item; 3647 3648 if (handle.callout == NULL) 3649 return (0); 3650 mtx_lock_spin(&callout_lock); 3651 item = handle.callout->c_arg; /* should be an official way to do this */ 3652 if ((handle.callout->c_func == &ng_timeout_trapoline) && 3653 (NGI_NODE(item) == node) && 3654 (callout_stop(handle.callout))) { 3655 /* 3656 * We successfully removed it from the queue before it ran 3657 * So now we need to unreference everything that was 3658 * given extra references. (NG_FREE_ITEM does this). 3659 */ 3660 mtx_unlock_spin(&callout_lock); 3661 NG_FREE_ITEM(item); 3662 return (1); 3663 } 3664 mtx_unlock_spin(&callout_lock); 3665 return (0); 3666 } 3667 3668 /* 3669 * Set the address, if none given, give the node here. 3670 */ 3671 void 3672 ng_replace_retaddr(node_p here, item_p item, ng_ID_t retaddr) 3673 { 3674 if (retaddr) { 3675 NGI_RETADDR(item) = retaddr; 3676 } else { 3677 /* 3678 * The old return address should be ok. 3679 * If there isn't one, use the address here. 3680 */ 3681 NGI_RETADDR(item) = ng_node2ID(here); 3682 } 3683 } 3684 3685 #define TESTING 3686 #ifdef TESTING 3687 /* just test all the macros */ 3688 void 3689 ng_macro_test(item_p item); 3690 void 3691 ng_macro_test(item_p item) 3692 { 3693 node_p node = NULL; 3694 hook_p hook = NULL; 3695 struct mbuf *m; 3696 meta_p meta; 3697 struct ng_mesg *msg; 3698 ng_ID_t retaddr; 3699 int error; 3700 3701 NGI_GET_M(item, m); 3702 NGI_GET_META(item, meta); 3703 NGI_GET_MSG(item, msg); 3704 retaddr = NGI_RETADDR(item); 3705 NG_SEND_DATA(error, hook, m, meta); 3706 NG_SEND_DATA_ONLY(error, hook, m); 3707 NG_FWD_NEW_DATA(error, item, hook, m); 3708 NG_FWD_ITEM_HOOK(error, item, hook); 3709 NG_SEND_MSG_HOOK(error, node, msg, hook, retaddr); 3710 NG_SEND_MSG_ID(error, node, msg, retaddr, retaddr); 3711 NG_SEND_MSG_PATH(error, node, msg, ".:", retaddr); 3712 NG_FWD_MSG_HOOK(error, node, item, hook, retaddr); 3713 } 3714 #endif /* TESTING */ 3715 3716