1 /* 2 * ng_base.c 3 */ 4 5 /*- 6 * Copyright (c) 1996-1999 Whistle Communications, Inc. 7 * All rights reserved. 8 * 9 * Subject to the following obligations and disclaimer of warranty, use and 10 * redistribution of this software, in source or object code forms, with or 11 * without modifications are expressly permitted by Whistle Communications; 12 * provided, however, that: 13 * 1. Any and all reproductions of the source or object code must include the 14 * copyright notice above and the following disclaimer of warranties; and 15 * 2. No rights are granted, in any manner or form, to use Whistle 16 * Communications, Inc. trademarks, including the mark "WHISTLE 17 * COMMUNICATIONS" on advertising, endorsements, or otherwise except as 18 * such appears in the above copyright notice or in the software. 19 * 20 * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND 21 * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO 22 * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE, 23 * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF 24 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT. 25 * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY 26 * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS 27 * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE. 28 * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES 29 * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING 30 * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, 31 * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR 32 * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY 33 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 34 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 35 * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY 36 * OF SUCH DAMAGE. 37 * 38 * Authors: Julian Elischer <julian@freebsd.org> 39 * Archie Cobbs <archie@freebsd.org> 40 * 41 * $FreeBSD$ 42 * $Whistle: ng_base.c,v 1.39 1999/01/28 23:54:53 julian Exp $ 43 */ 44 45 /* 46 * This file implements the base netgraph code. 47 */ 48 49 #include <sys/param.h> 50 #include <sys/systm.h> 51 #include <sys/ctype.h> 52 #include <sys/errno.h> 53 #include <sys/kdb.h> 54 #include <sys/kernel.h> 55 #include <sys/ktr.h> 56 #include <sys/limits.h> 57 #include <sys/malloc.h> 58 #include <sys/mbuf.h> 59 #include <sys/queue.h> 60 #include <sys/sysctl.h> 61 #include <sys/syslog.h> 62 63 #include <net/netisr.h> 64 65 #include <netgraph/ng_message.h> 66 #include <netgraph/netgraph.h> 67 #include <netgraph/ng_parse.h> 68 69 MODULE_VERSION(netgraph, NG_ABI_VERSION); 70 71 /* List of all active nodes */ 72 static LIST_HEAD(, ng_node) ng_nodelist; 73 static struct mtx ng_nodelist_mtx; 74 75 /* Mutex to protect topology events. */ 76 static struct mtx ng_topo_mtx; 77 78 #ifdef NETGRAPH_DEBUG 79 static struct mtx ngq_mtx; /* protects the queue item list */ 80 81 static SLIST_HEAD(, ng_node) ng_allnodes; 82 static LIST_HEAD(, ng_node) ng_freenodes; /* in debug, we never free() them */ 83 static SLIST_HEAD(, ng_hook) ng_allhooks; 84 static LIST_HEAD(, ng_hook) ng_freehooks; /* in debug, we never free() them */ 85 86 static void ng_dumpitems(void); 87 static void ng_dumpnodes(void); 88 static void ng_dumphooks(void); 89 90 #endif /* NETGRAPH_DEBUG */ 91 /* 92 * DEAD versions of the structures. 93 * In order to avoid races, it is sometimes neccesary to point 94 * at SOMETHING even though theoretically, the current entity is 95 * INVALID. Use these to avoid these races. 96 */ 97 struct ng_type ng_deadtype = { 98 NG_ABI_VERSION, 99 "dead", 100 NULL, /* modevent */ 101 NULL, /* constructor */ 102 NULL, /* rcvmsg */ 103 NULL, /* shutdown */ 104 NULL, /* newhook */ 105 NULL, /* findhook */ 106 NULL, /* connect */ 107 NULL, /* rcvdata */ 108 NULL, /* disconnect */ 109 NULL, /* cmdlist */ 110 }; 111 112 struct ng_node ng_deadnode = { 113 "dead", 114 &ng_deadtype, 115 NGF_INVALID, 116 1, /* refs */ 117 0, /* numhooks */ 118 NULL, /* private */ 119 0, /* ID */ 120 LIST_HEAD_INITIALIZER(ng_deadnode.hooks), 121 {}, /* all_nodes list entry */ 122 {}, /* id hashtable list entry */ 123 {}, /* workqueue entry */ 124 { 0, 125 {}, /* should never use! (should hang) */ 126 NULL, 127 &ng_deadnode.nd_input_queue.queue, 128 &ng_deadnode 129 }, 130 #ifdef NETGRAPH_DEBUG 131 ND_MAGIC, 132 __FILE__, 133 __LINE__, 134 {NULL} 135 #endif /* NETGRAPH_DEBUG */ 136 }; 137 138 struct ng_hook ng_deadhook = { 139 "dead", 140 NULL, /* private */ 141 HK_INVALID | HK_DEAD, 142 1, /* refs always >= 1 */ 143 0, /* undefined data link type */ 144 &ng_deadhook, /* Peer is self */ 145 &ng_deadnode, /* attached to deadnode */ 146 {}, /* hooks list */ 147 NULL, /* override rcvmsg() */ 148 NULL, /* override rcvdata() */ 149 #ifdef NETGRAPH_DEBUG 150 HK_MAGIC, 151 __FILE__, 152 __LINE__, 153 {NULL} 154 #endif /* NETGRAPH_DEBUG */ 155 }; 156 157 /* 158 * END DEAD STRUCTURES 159 */ 160 /* List nodes with unallocated work */ 161 static TAILQ_HEAD(, ng_node) ng_worklist = TAILQ_HEAD_INITIALIZER(ng_worklist); 162 static struct mtx ng_worklist_mtx; /* MUST LOCK NODE FIRST */ 163 164 /* List of installed types */ 165 static LIST_HEAD(, ng_type) ng_typelist; 166 static struct mtx ng_typelist_mtx; 167 168 /* Hash related definitions */ 169 /* XXX Don't need to initialise them because it's a LIST */ 170 #define NG_ID_HASH_SIZE 32 /* most systems wont need even this many */ 171 static LIST_HEAD(, ng_node) ng_ID_hash[NG_ID_HASH_SIZE]; 172 static struct mtx ng_idhash_mtx; 173 /* Method to find a node.. used twice so do it here */ 174 #define NG_IDHASH_FN(ID) ((ID) % (NG_ID_HASH_SIZE)) 175 #define NG_IDHASH_FIND(ID, node) \ 176 do { \ 177 mtx_assert(&ng_idhash_mtx, MA_OWNED); \ 178 LIST_FOREACH(node, &ng_ID_hash[NG_IDHASH_FN(ID)], \ 179 nd_idnodes) { \ 180 if (NG_NODE_IS_VALID(node) \ 181 && (NG_NODE_ID(node) == ID)) { \ 182 break; \ 183 } \ 184 } \ 185 } while (0) 186 187 188 /* Internal functions */ 189 static int ng_add_hook(node_p node, const char *name, hook_p * hookp); 190 static int ng_generic_msg(node_p here, item_p item, hook_p lasthook); 191 static ng_ID_t ng_decodeidname(const char *name); 192 static int ngb_mod_event(module_t mod, int event, void *data); 193 static void ng_worklist_remove(node_p node); 194 static void ngintr(void); 195 static int ng_apply_item(node_p node, item_p item, int rw); 196 static void ng_flush_input_queue(struct ng_queue * ngq); 197 static void ng_setisr(node_p node); 198 static node_p ng_ID2noderef(ng_ID_t ID); 199 static int ng_con_nodes(node_p node, const char *name, node_p node2, 200 const char *name2); 201 static void ng_con_part2(node_p node, hook_p hook, void *arg1, int arg2); 202 static void ng_con_part3(node_p node, hook_p hook, void *arg1, int arg2); 203 static int ng_mkpeer(node_p node, const char *name, 204 const char *name2, char *type); 205 206 /* Imported, these used to be externally visible, some may go back. */ 207 void ng_destroy_hook(hook_p hook); 208 node_p ng_name2noderef(node_p node, const char *name); 209 int ng_path2noderef(node_p here, const char *path, 210 node_p *dest, hook_p *lasthook); 211 int ng_make_node(const char *type, node_p *nodepp); 212 int ng_path_parse(char *addr, char **node, char **path, char **hook); 213 void ng_rmnode(node_p node, hook_p dummy1, void *dummy2, int dummy3); 214 void ng_unname(node_p node); 215 216 217 /* Our own netgraph malloc type */ 218 MALLOC_DEFINE(M_NETGRAPH, "netgraph", "netgraph structures and ctrl messages"); 219 MALLOC_DEFINE(M_NETGRAPH_HOOK, "netgraph_hook", "netgraph hook structures"); 220 MALLOC_DEFINE(M_NETGRAPH_NODE, "netgraph_node", "netgraph node structures"); 221 MALLOC_DEFINE(M_NETGRAPH_ITEM, "netgraph_item", "netgraph item structures"); 222 MALLOC_DEFINE(M_NETGRAPH_MSG, "netgraph_msg", "netgraph name storage"); 223 224 /* Should not be visible outside this file */ 225 226 #define _NG_ALLOC_HOOK(hook) \ 227 MALLOC(hook, hook_p, sizeof(*hook), M_NETGRAPH_HOOK, M_NOWAIT | M_ZERO) 228 #define _NG_ALLOC_NODE(node) \ 229 MALLOC(node, node_p, sizeof(*node), M_NETGRAPH_NODE, M_NOWAIT | M_ZERO) 230 231 #ifdef NETGRAPH_DEBUG /*----------------------------------------------*/ 232 /* 233 * In debug mode: 234 * In an attempt to help track reference count screwups 235 * we do not free objects back to the malloc system, but keep them 236 * in a local cache where we can examine them and keep information safely 237 * after they have been freed. 238 * We use this scheme for nodes and hooks, and to some extent for items. 239 */ 240 static __inline hook_p 241 ng_alloc_hook(void) 242 { 243 hook_p hook; 244 SLIST_ENTRY(ng_hook) temp; 245 mtx_lock(&ng_nodelist_mtx); 246 hook = LIST_FIRST(&ng_freehooks); 247 if (hook) { 248 LIST_REMOVE(hook, hk_hooks); 249 bcopy(&hook->hk_all, &temp, sizeof(temp)); 250 bzero(hook, sizeof(struct ng_hook)); 251 bcopy(&temp, &hook->hk_all, sizeof(temp)); 252 mtx_unlock(&ng_nodelist_mtx); 253 hook->hk_magic = HK_MAGIC; 254 } else { 255 mtx_unlock(&ng_nodelist_mtx); 256 _NG_ALLOC_HOOK(hook); 257 if (hook) { 258 hook->hk_magic = HK_MAGIC; 259 mtx_lock(&ng_nodelist_mtx); 260 SLIST_INSERT_HEAD(&ng_allhooks, hook, hk_all); 261 mtx_unlock(&ng_nodelist_mtx); 262 } 263 } 264 return (hook); 265 } 266 267 static __inline node_p 268 ng_alloc_node(void) 269 { 270 node_p node; 271 SLIST_ENTRY(ng_node) temp; 272 mtx_lock(&ng_nodelist_mtx); 273 node = LIST_FIRST(&ng_freenodes); 274 if (node) { 275 LIST_REMOVE(node, nd_nodes); 276 bcopy(&node->nd_all, &temp, sizeof(temp)); 277 bzero(node, sizeof(struct ng_node)); 278 bcopy(&temp, &node->nd_all, sizeof(temp)); 279 mtx_unlock(&ng_nodelist_mtx); 280 node->nd_magic = ND_MAGIC; 281 } else { 282 mtx_unlock(&ng_nodelist_mtx); 283 _NG_ALLOC_NODE(node); 284 if (node) { 285 node->nd_magic = ND_MAGIC; 286 mtx_lock(&ng_nodelist_mtx); 287 SLIST_INSERT_HEAD(&ng_allnodes, node, nd_all); 288 mtx_unlock(&ng_nodelist_mtx); 289 } 290 } 291 return (node); 292 } 293 294 #define NG_ALLOC_HOOK(hook) do { (hook) = ng_alloc_hook(); } while (0) 295 #define NG_ALLOC_NODE(node) do { (node) = ng_alloc_node(); } while (0) 296 297 298 #define NG_FREE_HOOK(hook) \ 299 do { \ 300 mtx_lock(&ng_nodelist_mtx); \ 301 LIST_INSERT_HEAD(&ng_freehooks, hook, hk_hooks); \ 302 hook->hk_magic = 0; \ 303 mtx_unlock(&ng_nodelist_mtx); \ 304 } while (0) 305 306 #define NG_FREE_NODE(node) \ 307 do { \ 308 mtx_lock(&ng_nodelist_mtx); \ 309 LIST_INSERT_HEAD(&ng_freenodes, node, nd_nodes); \ 310 node->nd_magic = 0; \ 311 mtx_unlock(&ng_nodelist_mtx); \ 312 } while (0) 313 314 #else /* NETGRAPH_DEBUG */ /*----------------------------------------------*/ 315 316 #define NG_ALLOC_HOOK(hook) _NG_ALLOC_HOOK(hook) 317 #define NG_ALLOC_NODE(node) _NG_ALLOC_NODE(node) 318 319 #define NG_FREE_HOOK(hook) do { FREE((hook), M_NETGRAPH_HOOK); } while (0) 320 #define NG_FREE_NODE(node) do { FREE((node), M_NETGRAPH_NODE); } while (0) 321 322 #endif /* NETGRAPH_DEBUG */ /*----------------------------------------------*/ 323 324 /* Set this to kdb_enter("X") to catch all errors as they occur */ 325 #ifndef TRAP_ERROR 326 #define TRAP_ERROR() 327 #endif 328 329 static ng_ID_t nextID = 1; 330 331 #ifdef INVARIANTS 332 #define CHECK_DATA_MBUF(m) do { \ 333 struct mbuf *n; \ 334 int total; \ 335 \ 336 M_ASSERTPKTHDR(m); \ 337 for (total = 0, n = (m); n != NULL; n = n->m_next) { \ 338 total += n->m_len; \ 339 if (n->m_nextpkt != NULL) \ 340 panic("%s: m_nextpkt", __func__); \ 341 } \ 342 \ 343 if ((m)->m_pkthdr.len != total) { \ 344 panic("%s: %d != %d", \ 345 __func__, (m)->m_pkthdr.len, total); \ 346 } \ 347 } while (0) 348 #else 349 #define CHECK_DATA_MBUF(m) 350 #endif 351 352 353 /************************************************************************ 354 Parse type definitions for generic messages 355 ************************************************************************/ 356 357 /* Handy structure parse type defining macro */ 358 #define DEFINE_PARSE_STRUCT_TYPE(lo, up, args) \ 359 static const struct ng_parse_struct_field \ 360 ng_ ## lo ## _type_fields[] = NG_GENERIC_ ## up ## _INFO args; \ 361 static const struct ng_parse_type ng_generic_ ## lo ## _type = { \ 362 &ng_parse_struct_type, \ 363 &ng_ ## lo ## _type_fields \ 364 } 365 366 DEFINE_PARSE_STRUCT_TYPE(mkpeer, MKPEER, ()); 367 DEFINE_PARSE_STRUCT_TYPE(connect, CONNECT, ()); 368 DEFINE_PARSE_STRUCT_TYPE(name, NAME, ()); 369 DEFINE_PARSE_STRUCT_TYPE(rmhook, RMHOOK, ()); 370 DEFINE_PARSE_STRUCT_TYPE(nodeinfo, NODEINFO, ()); 371 DEFINE_PARSE_STRUCT_TYPE(typeinfo, TYPEINFO, ()); 372 DEFINE_PARSE_STRUCT_TYPE(linkinfo, LINKINFO, (&ng_generic_nodeinfo_type)); 373 374 /* Get length of an array when the length is stored as a 32 bit 375 value immediately preceding the array -- as with struct namelist 376 and struct typelist. */ 377 static int 378 ng_generic_list_getLength(const struct ng_parse_type *type, 379 const u_char *start, const u_char *buf) 380 { 381 return *((const u_int32_t *)(buf - 4)); 382 } 383 384 /* Get length of the array of struct linkinfo inside a struct hooklist */ 385 static int 386 ng_generic_linkinfo_getLength(const struct ng_parse_type *type, 387 const u_char *start, const u_char *buf) 388 { 389 const struct hooklist *hl = (const struct hooklist *)start; 390 391 return hl->nodeinfo.hooks; 392 } 393 394 /* Array type for a variable length array of struct namelist */ 395 static const struct ng_parse_array_info ng_nodeinfoarray_type_info = { 396 &ng_generic_nodeinfo_type, 397 &ng_generic_list_getLength 398 }; 399 static const struct ng_parse_type ng_generic_nodeinfoarray_type = { 400 &ng_parse_array_type, 401 &ng_nodeinfoarray_type_info 402 }; 403 404 /* Array type for a variable length array of struct typelist */ 405 static const struct ng_parse_array_info ng_typeinfoarray_type_info = { 406 &ng_generic_typeinfo_type, 407 &ng_generic_list_getLength 408 }; 409 static const struct ng_parse_type ng_generic_typeinfoarray_type = { 410 &ng_parse_array_type, 411 &ng_typeinfoarray_type_info 412 }; 413 414 /* Array type for array of struct linkinfo in struct hooklist */ 415 static const struct ng_parse_array_info ng_generic_linkinfo_array_type_info = { 416 &ng_generic_linkinfo_type, 417 &ng_generic_linkinfo_getLength 418 }; 419 static const struct ng_parse_type ng_generic_linkinfo_array_type = { 420 &ng_parse_array_type, 421 &ng_generic_linkinfo_array_type_info 422 }; 423 424 DEFINE_PARSE_STRUCT_TYPE(typelist, TYPELIST, (&ng_generic_nodeinfoarray_type)); 425 DEFINE_PARSE_STRUCT_TYPE(hooklist, HOOKLIST, 426 (&ng_generic_nodeinfo_type, &ng_generic_linkinfo_array_type)); 427 DEFINE_PARSE_STRUCT_TYPE(listnodes, LISTNODES, 428 (&ng_generic_nodeinfoarray_type)); 429 430 /* List of commands and how to convert arguments to/from ASCII */ 431 static const struct ng_cmdlist ng_generic_cmds[] = { 432 { 433 NGM_GENERIC_COOKIE, 434 NGM_SHUTDOWN, 435 "shutdown", 436 NULL, 437 NULL 438 }, 439 { 440 NGM_GENERIC_COOKIE, 441 NGM_MKPEER, 442 "mkpeer", 443 &ng_generic_mkpeer_type, 444 NULL 445 }, 446 { 447 NGM_GENERIC_COOKIE, 448 NGM_CONNECT, 449 "connect", 450 &ng_generic_connect_type, 451 NULL 452 }, 453 { 454 NGM_GENERIC_COOKIE, 455 NGM_NAME, 456 "name", 457 &ng_generic_name_type, 458 NULL 459 }, 460 { 461 NGM_GENERIC_COOKIE, 462 NGM_RMHOOK, 463 "rmhook", 464 &ng_generic_rmhook_type, 465 NULL 466 }, 467 { 468 NGM_GENERIC_COOKIE, 469 NGM_NODEINFO, 470 "nodeinfo", 471 NULL, 472 &ng_generic_nodeinfo_type 473 }, 474 { 475 NGM_GENERIC_COOKIE, 476 NGM_LISTHOOKS, 477 "listhooks", 478 NULL, 479 &ng_generic_hooklist_type 480 }, 481 { 482 NGM_GENERIC_COOKIE, 483 NGM_LISTNAMES, 484 "listnames", 485 NULL, 486 &ng_generic_listnodes_type /* same as NGM_LISTNODES */ 487 }, 488 { 489 NGM_GENERIC_COOKIE, 490 NGM_LISTNODES, 491 "listnodes", 492 NULL, 493 &ng_generic_listnodes_type 494 }, 495 { 496 NGM_GENERIC_COOKIE, 497 NGM_LISTTYPES, 498 "listtypes", 499 NULL, 500 &ng_generic_typeinfo_type 501 }, 502 { 503 NGM_GENERIC_COOKIE, 504 NGM_TEXT_CONFIG, 505 "textconfig", 506 NULL, 507 &ng_parse_string_type 508 }, 509 { 510 NGM_GENERIC_COOKIE, 511 NGM_TEXT_STATUS, 512 "textstatus", 513 NULL, 514 &ng_parse_string_type 515 }, 516 { 517 NGM_GENERIC_COOKIE, 518 NGM_ASCII2BINARY, 519 "ascii2binary", 520 &ng_parse_ng_mesg_type, 521 &ng_parse_ng_mesg_type 522 }, 523 { 524 NGM_GENERIC_COOKIE, 525 NGM_BINARY2ASCII, 526 "binary2ascii", 527 &ng_parse_ng_mesg_type, 528 &ng_parse_ng_mesg_type 529 }, 530 { 0 } 531 }; 532 533 /************************************************************************ 534 Node routines 535 ************************************************************************/ 536 537 /* 538 * Instantiate a node of the requested type 539 */ 540 int 541 ng_make_node(const char *typename, node_p *nodepp) 542 { 543 struct ng_type *type; 544 int error; 545 546 /* Check that the type makes sense */ 547 if (typename == NULL) { 548 TRAP_ERROR(); 549 return (EINVAL); 550 } 551 552 /* Locate the node type. If we fail we return. Do not try to load 553 * module. 554 */ 555 if ((type = ng_findtype(typename)) == NULL) 556 return (ENXIO); 557 558 /* 559 * If we have a constructor, then make the node and 560 * call the constructor to do type specific initialisation. 561 */ 562 if (type->constructor != NULL) { 563 if ((error = ng_make_node_common(type, nodepp)) == 0) { 564 if ((error = ((*type->constructor)(*nodepp)) != 0)) { 565 NG_NODE_UNREF(*nodepp); 566 } 567 } 568 } else { 569 /* 570 * Node has no constructor. We cannot ask for one 571 * to be made. It must be brought into existance by 572 * some external agency. The external agency should 573 * call ng_make_node_common() directly to get the 574 * netgraph part initialised. 575 */ 576 TRAP_ERROR(); 577 error = EINVAL; 578 } 579 return (error); 580 } 581 582 /* 583 * Generic node creation. Called by node initialisation for externally 584 * instantiated nodes (e.g. hardware, sockets, etc ). 585 * The returned node has a reference count of 1. 586 */ 587 int 588 ng_make_node_common(struct ng_type *type, node_p *nodepp) 589 { 590 node_p node; 591 592 /* Require the node type to have been already installed */ 593 if (ng_findtype(type->name) == NULL) { 594 TRAP_ERROR(); 595 return (EINVAL); 596 } 597 598 /* Make a node and try attach it to the type */ 599 NG_ALLOC_NODE(node); 600 if (node == NULL) { 601 TRAP_ERROR(); 602 return (ENOMEM); 603 } 604 node->nd_type = type; 605 NG_NODE_REF(node); /* note reference */ 606 type->refs++; 607 608 mtx_init(&node->nd_input_queue.q_mtx, "ng_node", NULL, MTX_SPIN); 609 node->nd_input_queue.queue = NULL; 610 node->nd_input_queue.last = &node->nd_input_queue.queue; 611 node->nd_input_queue.q_flags = 0; 612 node->nd_input_queue.q_node = node; 613 614 /* Initialize hook list for new node */ 615 LIST_INIT(&node->nd_hooks); 616 617 /* Link us into the node linked list */ 618 mtx_lock(&ng_nodelist_mtx); 619 LIST_INSERT_HEAD(&ng_nodelist, node, nd_nodes); 620 mtx_unlock(&ng_nodelist_mtx); 621 622 623 /* get an ID and put us in the hash chain */ 624 mtx_lock(&ng_idhash_mtx); 625 for (;;) { /* wrap protection, even if silly */ 626 node_p node2 = NULL; 627 node->nd_ID = nextID++; /* 137/second for 1 year before wrap */ 628 629 /* Is there a problem with the new number? */ 630 NG_IDHASH_FIND(node->nd_ID, node2); /* already taken? */ 631 if ((node->nd_ID != 0) && (node2 == NULL)) { 632 break; 633 } 634 } 635 LIST_INSERT_HEAD(&ng_ID_hash[NG_IDHASH_FN(node->nd_ID)], 636 node, nd_idnodes); 637 mtx_unlock(&ng_idhash_mtx); 638 639 /* Done */ 640 *nodepp = node; 641 return (0); 642 } 643 644 /* 645 * Forceably start the shutdown process on a node. Either call 646 * it's shutdown method, or do the default shutdown if there is 647 * no type-specific method. 648 * 649 * We can only be called form a shutdown message, so we know we have 650 * a writer lock, and therefore exclusive access. It also means 651 * that we should not be on the work queue, but we check anyhow. 652 * 653 * Persistent node types must have a type-specific method which 654 * Allocates a new node in which case, this one is irretrievably going away, 655 * or cleans up anything it needs, and just makes the node valid again, 656 * in which case we allow the node to survive. 657 * 658 * XXX We need to think of how to tell a persistant node that we 659 * REALLY need to go away because the hardware has gone or we 660 * are rebooting.... etc. 661 */ 662 void 663 ng_rmnode(node_p node, hook_p dummy1, void *dummy2, int dummy3) 664 { 665 hook_p hook; 666 667 /* Check if it's already shutting down */ 668 if ((node->nd_flags & NGF_CLOSING) != 0) 669 return; 670 671 if (node == &ng_deadnode) { 672 printf ("shutdown called on deadnode\n"); 673 return; 674 } 675 676 /* Add an extra reference so it doesn't go away during this */ 677 NG_NODE_REF(node); 678 679 /* 680 * Mark it invalid so any newcomers know not to try use it 681 * Also add our own mark so we can't recurse 682 * note that NGF_INVALID does not do this as it's also set during 683 * creation 684 */ 685 node->nd_flags |= NGF_INVALID|NGF_CLOSING; 686 687 /* If node has its pre-shutdown method, then call it first*/ 688 if (node->nd_type && node->nd_type->close) 689 (*node->nd_type->close)(node); 690 691 /* Notify all remaining connected nodes to disconnect */ 692 while ((hook = LIST_FIRST(&node->nd_hooks)) != NULL) 693 ng_destroy_hook(hook); 694 695 /* 696 * Drain the input queue forceably. 697 * it has no hooks so what's it going to do, bleed on someone? 698 * Theoretically we came here from a queue entry that was added 699 * Just before the queue was closed, so it should be empty anyway. 700 * Also removes us from worklist if needed. 701 */ 702 ng_flush_input_queue(&node->nd_input_queue); 703 704 /* Ask the type if it has anything to do in this case */ 705 if (node->nd_type && node->nd_type->shutdown) { 706 (*node->nd_type->shutdown)(node); 707 if (NG_NODE_IS_VALID(node)) { 708 /* 709 * Well, blow me down if the node code hasn't declared 710 * that it doesn't want to die. 711 * Presumably it is a persistant node. 712 * If we REALLY want it to go away, 713 * e.g. hardware going away, 714 * Our caller should set NGF_REALLY_DIE in nd_flags. 715 */ 716 node->nd_flags &= ~(NGF_INVALID|NGF_CLOSING); 717 NG_NODE_UNREF(node); /* Assume they still have theirs */ 718 return; 719 } 720 } else { /* do the default thing */ 721 NG_NODE_UNREF(node); 722 } 723 724 ng_unname(node); /* basically a NOP these days */ 725 726 /* 727 * Remove extra reference, possibly the last 728 * Possible other holders of references may include 729 * timeout callouts, but theoretically the node's supposed to 730 * have cancelled them. Possibly hardware dependencies may 731 * force a driver to 'linger' with a reference. 732 */ 733 NG_NODE_UNREF(node); 734 } 735 736 /* 737 * Remove a reference to the node, possibly the last. 738 * deadnode always acts as it it were the last. 739 */ 740 int 741 ng_unref_node(node_p node) 742 { 743 int v; 744 745 if (node == &ng_deadnode) { 746 return (0); 747 } 748 749 do { 750 v = node->nd_refs - 1; 751 } while (! atomic_cmpset_int(&node->nd_refs, v + 1, v)); 752 753 if (v == 0) { /* we were the last */ 754 755 mtx_lock(&ng_nodelist_mtx); 756 node->nd_type->refs--; /* XXX maybe should get types lock? */ 757 LIST_REMOVE(node, nd_nodes); 758 mtx_unlock(&ng_nodelist_mtx); 759 760 mtx_lock(&ng_idhash_mtx); 761 LIST_REMOVE(node, nd_idnodes); 762 mtx_unlock(&ng_idhash_mtx); 763 764 mtx_destroy(&node->nd_input_queue.q_mtx); 765 NG_FREE_NODE(node); 766 } 767 return (v); 768 } 769 770 /************************************************************************ 771 Node ID handling 772 ************************************************************************/ 773 static node_p 774 ng_ID2noderef(ng_ID_t ID) 775 { 776 node_p node; 777 mtx_lock(&ng_idhash_mtx); 778 NG_IDHASH_FIND(ID, node); 779 if(node) 780 NG_NODE_REF(node); 781 mtx_unlock(&ng_idhash_mtx); 782 return(node); 783 } 784 785 ng_ID_t 786 ng_node2ID(node_p node) 787 { 788 return (node ? NG_NODE_ID(node) : 0); 789 } 790 791 /************************************************************************ 792 Node name handling 793 ************************************************************************/ 794 795 /* 796 * Assign a node a name. Once assigned, the name cannot be changed. 797 */ 798 int 799 ng_name_node(node_p node, const char *name) 800 { 801 int i; 802 node_p node2; 803 804 /* Check the name is valid */ 805 for (i = 0; i < NG_NODESIZ; i++) { 806 if (name[i] == '\0' || name[i] == '.' || name[i] == ':') 807 break; 808 } 809 if (i == 0 || name[i] != '\0') { 810 TRAP_ERROR(); 811 return (EINVAL); 812 } 813 if (ng_decodeidname(name) != 0) { /* valid IDs not allowed here */ 814 TRAP_ERROR(); 815 return (EINVAL); 816 } 817 818 /* Check the name isn't already being used */ 819 if ((node2 = ng_name2noderef(node, name)) != NULL) { 820 NG_NODE_UNREF(node2); 821 TRAP_ERROR(); 822 return (EADDRINUSE); 823 } 824 825 /* copy it */ 826 strlcpy(NG_NODE_NAME(node), name, NG_NODESIZ); 827 828 return (0); 829 } 830 831 /* 832 * Find a node by absolute name. The name should NOT end with ':' 833 * The name "." means "this node" and "[xxx]" means "the node 834 * with ID (ie, at address) xxx". 835 * 836 * Returns the node if found, else NULL. 837 * Eventually should add something faster than a sequential search. 838 * Note it aquires a reference on the node so you can be sure it's still there. 839 */ 840 node_p 841 ng_name2noderef(node_p here, const char *name) 842 { 843 node_p node; 844 ng_ID_t temp; 845 846 /* "." means "this node" */ 847 if (strcmp(name, ".") == 0) { 848 NG_NODE_REF(here); 849 return(here); 850 } 851 852 /* Check for name-by-ID */ 853 if ((temp = ng_decodeidname(name)) != 0) { 854 return (ng_ID2noderef(temp)); 855 } 856 857 /* Find node by name */ 858 mtx_lock(&ng_nodelist_mtx); 859 LIST_FOREACH(node, &ng_nodelist, nd_nodes) { 860 if (NG_NODE_IS_VALID(node) 861 && NG_NODE_HAS_NAME(node) 862 && (strcmp(NG_NODE_NAME(node), name) == 0)) { 863 break; 864 } 865 } 866 if (node) 867 NG_NODE_REF(node); 868 mtx_unlock(&ng_nodelist_mtx); 869 return (node); 870 } 871 872 /* 873 * Decode an ID name, eg. "[f03034de]". Returns 0 if the 874 * string is not valid, otherwise returns the value. 875 */ 876 static ng_ID_t 877 ng_decodeidname(const char *name) 878 { 879 const int len = strlen(name); 880 char *eptr; 881 u_long val; 882 883 /* Check for proper length, brackets, no leading junk */ 884 if ((len < 3) 885 || (name[0] != '[') 886 || (name[len - 1] != ']') 887 || (!isxdigit(name[1]))) { 888 return ((ng_ID_t)0); 889 } 890 891 /* Decode number */ 892 val = strtoul(name + 1, &eptr, 16); 893 if ((eptr - name != len - 1) 894 || (val == ULONG_MAX) 895 || (val == 0)) { 896 return ((ng_ID_t)0); 897 } 898 return (ng_ID_t)val; 899 } 900 901 /* 902 * Remove a name from a node. This should only be called 903 * when shutting down and removing the node. 904 * IF we allow name changing this may be more resurected. 905 */ 906 void 907 ng_unname(node_p node) 908 { 909 } 910 911 /************************************************************************ 912 Hook routines 913 Names are not optional. Hooks are always connected, except for a 914 brief moment within these routines. On invalidation or during creation 915 they are connected to the 'dead' hook. 916 ************************************************************************/ 917 918 /* 919 * Remove a hook reference 920 */ 921 void 922 ng_unref_hook(hook_p hook) 923 { 924 int v; 925 926 if (hook == &ng_deadhook) { 927 return; 928 } 929 do { 930 v = hook->hk_refs; 931 } while (! atomic_cmpset_int(&hook->hk_refs, v, v - 1)); 932 933 if (v == 1) { /* we were the last */ 934 if (_NG_HOOK_NODE(hook)) { /* it'll probably be ng_deadnode */ 935 _NG_NODE_UNREF((_NG_HOOK_NODE(hook))); 936 hook->hk_node = NULL; 937 } 938 NG_FREE_HOOK(hook); 939 } 940 } 941 942 /* 943 * Add an unconnected hook to a node. Only used internally. 944 * Assumes node is locked. (XXX not yet true ) 945 */ 946 static int 947 ng_add_hook(node_p node, const char *name, hook_p *hookp) 948 { 949 hook_p hook; 950 int error = 0; 951 952 /* Check that the given name is good */ 953 if (name == NULL) { 954 TRAP_ERROR(); 955 return (EINVAL); 956 } 957 if (ng_findhook(node, name) != NULL) { 958 TRAP_ERROR(); 959 return (EEXIST); 960 } 961 962 /* Allocate the hook and link it up */ 963 NG_ALLOC_HOOK(hook); 964 if (hook == NULL) { 965 TRAP_ERROR(); 966 return (ENOMEM); 967 } 968 hook->hk_refs = 1; /* add a reference for us to return */ 969 hook->hk_flags = HK_INVALID; 970 hook->hk_peer = &ng_deadhook; /* start off this way */ 971 hook->hk_node = node; 972 NG_NODE_REF(node); /* each hook counts as a reference */ 973 974 /* Set hook name */ 975 strlcpy(NG_HOOK_NAME(hook), name, NG_HOOKSIZ); 976 977 /* 978 * Check if the node type code has something to say about it 979 * If it fails, the unref of the hook will also unref the node. 980 */ 981 if (node->nd_type->newhook != NULL) { 982 if ((error = (*node->nd_type->newhook)(node, hook, name))) { 983 NG_HOOK_UNREF(hook); /* this frees the hook */ 984 return (error); 985 } 986 } 987 /* 988 * The 'type' agrees so far, so go ahead and link it in. 989 * We'll ask again later when we actually connect the hooks. 990 */ 991 LIST_INSERT_HEAD(&node->nd_hooks, hook, hk_hooks); 992 node->nd_numhooks++; 993 NG_HOOK_REF(hook); /* one for the node */ 994 995 if (hookp) 996 *hookp = hook; 997 return (0); 998 } 999 1000 /* 1001 * Find a hook 1002 * 1003 * Node types may supply their own optimized routines for finding 1004 * hooks. If none is supplied, we just do a linear search. 1005 * XXX Possibly we should add a reference to the hook? 1006 */ 1007 hook_p 1008 ng_findhook(node_p node, const char *name) 1009 { 1010 hook_p hook; 1011 1012 if (node->nd_type->findhook != NULL) 1013 return (*node->nd_type->findhook)(node, name); 1014 LIST_FOREACH(hook, &node->nd_hooks, hk_hooks) { 1015 if (NG_HOOK_IS_VALID(hook) 1016 && (strcmp(NG_HOOK_NAME(hook), name) == 0)) 1017 return (hook); 1018 } 1019 return (NULL); 1020 } 1021 1022 /* 1023 * Destroy a hook 1024 * 1025 * As hooks are always attached, this really destroys two hooks. 1026 * The one given, and the one attached to it. Disconnect the hooks 1027 * from each other first. We reconnect the peer hook to the 'dead' 1028 * hook so that it can still exist after we depart. We then 1029 * send the peer its own destroy message. This ensures that we only 1030 * interact with the peer's structures when it is locked processing that 1031 * message. We hold a reference to the peer hook so we are guaranteed that 1032 * the peer hook and node are still going to exist until 1033 * we are finished there as the hook holds a ref on the node. 1034 * We run this same code again on the peer hook, but that time it is already 1035 * attached to the 'dead' hook. 1036 * 1037 * This routine is called at all stages of hook creation 1038 * on error detection and must be able to handle any such stage. 1039 */ 1040 void 1041 ng_destroy_hook(hook_p hook) 1042 { 1043 hook_p peer; 1044 node_p node; 1045 1046 if (hook == &ng_deadhook) { /* better safe than sorry */ 1047 printf("ng_destroy_hook called on deadhook\n"); 1048 return; 1049 } 1050 1051 /* 1052 * Protect divorce process with mutex, to avoid races on 1053 * simultaneous disconnect. 1054 */ 1055 mtx_lock(&ng_topo_mtx); 1056 1057 hook->hk_flags |= HK_INVALID; 1058 1059 peer = NG_HOOK_PEER(hook); 1060 node = NG_HOOK_NODE(hook); 1061 1062 if (peer && (peer != &ng_deadhook)) { 1063 /* 1064 * Set the peer to point to ng_deadhook 1065 * from this moment on we are effectively independent it. 1066 * send it an rmhook message of it's own. 1067 */ 1068 peer->hk_peer = &ng_deadhook; /* They no longer know us */ 1069 hook->hk_peer = &ng_deadhook; /* Nor us, them */ 1070 if (NG_HOOK_NODE(peer) == &ng_deadnode) { 1071 /* 1072 * If it's already divorced from a node, 1073 * just free it. 1074 */ 1075 mtx_unlock(&ng_topo_mtx); 1076 } else { 1077 mtx_unlock(&ng_topo_mtx); 1078 ng_rmhook_self(peer); /* Send it a surprise */ 1079 } 1080 NG_HOOK_UNREF(peer); /* account for peer link */ 1081 NG_HOOK_UNREF(hook); /* account for peer link */ 1082 } else 1083 mtx_unlock(&ng_topo_mtx); 1084 1085 mtx_assert(&ng_topo_mtx, MA_NOTOWNED); 1086 1087 /* 1088 * Remove the hook from the node's list to avoid possible recursion 1089 * in case the disconnection results in node shutdown. 1090 */ 1091 if (node == &ng_deadnode) { /* happens if called from ng_con_nodes() */ 1092 return; 1093 } 1094 LIST_REMOVE(hook, hk_hooks); 1095 node->nd_numhooks--; 1096 if (node->nd_type->disconnect) { 1097 /* 1098 * The type handler may elect to destroy the node so don't 1099 * trust its existance after this point. (except 1100 * that we still hold a reference on it. (which we 1101 * inherrited from the hook we are destroying) 1102 */ 1103 (*node->nd_type->disconnect) (hook); 1104 } 1105 1106 /* 1107 * Note that because we will point to ng_deadnode, the original node 1108 * is not decremented automatically so we do that manually. 1109 */ 1110 _NG_HOOK_NODE(hook) = &ng_deadnode; 1111 NG_NODE_UNREF(node); /* We no longer point to it so adjust count */ 1112 NG_HOOK_UNREF(hook); /* Account for linkage (in list) to node */ 1113 } 1114 1115 /* 1116 * Take two hooks on a node and merge the connection so that the given node 1117 * is effectively bypassed. 1118 */ 1119 int 1120 ng_bypass(hook_p hook1, hook_p hook2) 1121 { 1122 if (hook1->hk_node != hook2->hk_node) { 1123 TRAP_ERROR(); 1124 return (EINVAL); 1125 } 1126 hook1->hk_peer->hk_peer = hook2->hk_peer; 1127 hook2->hk_peer->hk_peer = hook1->hk_peer; 1128 1129 hook1->hk_peer = &ng_deadhook; 1130 hook2->hk_peer = &ng_deadhook; 1131 1132 NG_HOOK_UNREF(hook1); 1133 NG_HOOK_UNREF(hook2); 1134 1135 /* XXX If we ever cache methods on hooks update them as well */ 1136 ng_destroy_hook(hook1); 1137 ng_destroy_hook(hook2); 1138 return (0); 1139 } 1140 1141 /* 1142 * Install a new netgraph type 1143 */ 1144 int 1145 ng_newtype(struct ng_type *tp) 1146 { 1147 const size_t namelen = strlen(tp->name); 1148 1149 /* Check version and type name fields */ 1150 if ((tp->version != NG_ABI_VERSION) 1151 || (namelen == 0) 1152 || (namelen >= NG_TYPESIZ)) { 1153 TRAP_ERROR(); 1154 if (tp->version != NG_ABI_VERSION) { 1155 printf("Netgraph: Node type rejected. ABI mismatch. Suggest recompile\n"); 1156 } 1157 return (EINVAL); 1158 } 1159 1160 /* Check for name collision */ 1161 if (ng_findtype(tp->name) != NULL) { 1162 TRAP_ERROR(); 1163 return (EEXIST); 1164 } 1165 1166 1167 /* Link in new type */ 1168 mtx_lock(&ng_typelist_mtx); 1169 LIST_INSERT_HEAD(&ng_typelist, tp, types); 1170 tp->refs = 1; /* first ref is linked list */ 1171 mtx_unlock(&ng_typelist_mtx); 1172 return (0); 1173 } 1174 1175 /* 1176 * unlink a netgraph type 1177 * If no examples exist 1178 */ 1179 int 1180 ng_rmtype(struct ng_type *tp) 1181 { 1182 /* Check for name collision */ 1183 if (tp->refs != 1) { 1184 TRAP_ERROR(); 1185 return (EBUSY); 1186 } 1187 1188 /* Unlink type */ 1189 mtx_lock(&ng_typelist_mtx); 1190 LIST_REMOVE(tp, types); 1191 mtx_unlock(&ng_typelist_mtx); 1192 return (0); 1193 } 1194 1195 /* 1196 * Look for a type of the name given 1197 */ 1198 struct ng_type * 1199 ng_findtype(const char *typename) 1200 { 1201 struct ng_type *type; 1202 1203 mtx_lock(&ng_typelist_mtx); 1204 LIST_FOREACH(type, &ng_typelist, types) { 1205 if (strcmp(type->name, typename) == 0) 1206 break; 1207 } 1208 mtx_unlock(&ng_typelist_mtx); 1209 return (type); 1210 } 1211 1212 /************************************************************************ 1213 Composite routines 1214 ************************************************************************/ 1215 /* 1216 * Connect two nodes using the specified hooks, using queued functions. 1217 */ 1218 static void 1219 ng_con_part3(node_p node, hook_p hook, void *arg1, int arg2) 1220 { 1221 1222 /* 1223 * When we run, we know that the node 'node' is locked for us. 1224 * Our caller has a reference on the hook. 1225 * Our caller has a reference on the node. 1226 * (In this case our caller is ng_apply_item() ). 1227 * The peer hook has a reference on the hook. 1228 * We are all set up except for the final call to the node, and 1229 * the clearing of the INVALID flag. 1230 */ 1231 if (NG_HOOK_NODE(hook) == &ng_deadnode) { 1232 /* 1233 * The node must have been freed again since we last visited 1234 * here. ng_destry_hook() has this effect but nothing else does. 1235 * We should just release our references and 1236 * free anything we can think of. 1237 * Since we know it's been destroyed, and it's our caller 1238 * that holds the references, just return. 1239 */ 1240 return ; 1241 } 1242 if (hook->hk_node->nd_type->connect) { 1243 if ((*hook->hk_node->nd_type->connect) (hook)) { 1244 ng_destroy_hook(hook); /* also zaps peer */ 1245 printf("failed in ng_con_part3()\n"); 1246 return ; 1247 } 1248 } 1249 /* 1250 * XXX this is wrong for SMP. Possibly we need 1251 * to separate out 'create' and 'invalid' flags. 1252 * should only set flags on hooks we have locked under our node. 1253 */ 1254 hook->hk_flags &= ~HK_INVALID; 1255 return ; 1256 } 1257 1258 static void 1259 ng_con_part2(node_p node, hook_p hook, void *arg1, int arg2) 1260 { 1261 hook_p peer; 1262 1263 /* 1264 * When we run, we know that the node 'node' is locked for us. 1265 * Our caller has a reference on the hook. 1266 * Our caller has a reference on the node. 1267 * (In this case our caller is ng_apply_item() ). 1268 * The peer hook has a reference on the hook. 1269 * our node pointer points to the 'dead' node. 1270 * First check the hook name is unique. 1271 * Should not happen because we checked before queueing this. 1272 */ 1273 if (ng_findhook(node, NG_HOOK_NAME(hook)) != NULL) { 1274 TRAP_ERROR(); 1275 ng_destroy_hook(hook); /* should destroy peer too */ 1276 printf("failed in ng_con_part2()\n"); 1277 return ; 1278 } 1279 /* 1280 * Check if the node type code has something to say about it 1281 * If it fails, the unref of the hook will also unref the attached node, 1282 * however since that node is 'ng_deadnode' this will do nothing. 1283 * The peer hook will also be destroyed. 1284 */ 1285 if (node->nd_type->newhook != NULL) { 1286 if ((*node->nd_type->newhook)(node, hook, hook->hk_name)) { 1287 ng_destroy_hook(hook); /* should destroy peer too */ 1288 printf("failed in ng_con_part2()\n"); 1289 return ; 1290 } 1291 } 1292 1293 /* 1294 * The 'type' agrees so far, so go ahead and link it in. 1295 * We'll ask again later when we actually connect the hooks. 1296 */ 1297 hook->hk_node = node; /* just overwrite ng_deadnode */ 1298 NG_NODE_REF(node); /* each hook counts as a reference */ 1299 LIST_INSERT_HEAD(&node->nd_hooks, hook, hk_hooks); 1300 node->nd_numhooks++; 1301 NG_HOOK_REF(hook); /* one for the node */ 1302 1303 /* 1304 * We now have a symetrical situation, where both hooks have been 1305 * linked to their nodes, the newhook methods have been called 1306 * And the references are all correct. The hooks are still marked 1307 * as invalid, as we have not called the 'connect' methods 1308 * yet. 1309 * We can call the local one immediatly as we have the 1310 * node locked, but we need to queue the remote one. 1311 */ 1312 if (hook->hk_node->nd_type->connect) { 1313 if ((*hook->hk_node->nd_type->connect) (hook)) { 1314 ng_destroy_hook(hook); /* also zaps peer */ 1315 printf("failed in ng_con_part2(A)\n"); 1316 return ; 1317 } 1318 } 1319 1320 /* 1321 * Acquire topo mutex to avoid race with ng_destroy_hook(). 1322 */ 1323 mtx_lock(&ng_topo_mtx); 1324 peer = hook->hk_peer; 1325 if (peer == &ng_deadhook) { 1326 mtx_unlock(&ng_topo_mtx); 1327 printf("failed in ng_con_part2(B)\n"); 1328 ng_destroy_hook(hook); 1329 return ; 1330 } 1331 mtx_unlock(&ng_topo_mtx); 1332 1333 if (ng_send_fn(peer->hk_node, peer, &ng_con_part3, arg1, arg2)) { 1334 printf("failed in ng_con_part2(C)\n"); 1335 ng_destroy_hook(hook); /* also zaps peer */ 1336 return ; 1337 } 1338 hook->hk_flags &= ~HK_INVALID; /* need both to be able to work */ 1339 return ; 1340 } 1341 1342 /* 1343 * Connect this node with another node. We assume that this node is 1344 * currently locked, as we are only called from an NGM_CONNECT message. 1345 */ 1346 static int 1347 ng_con_nodes(node_p node, const char *name, node_p node2, const char *name2) 1348 { 1349 int error; 1350 hook_p hook; 1351 hook_p hook2; 1352 1353 if (ng_findhook(node2, name2) != NULL) { 1354 return(EEXIST); 1355 } 1356 if ((error = ng_add_hook(node, name, &hook))) /* gives us a ref */ 1357 return (error); 1358 /* Allocate the other hook and link it up */ 1359 NG_ALLOC_HOOK(hook2); 1360 if (hook2 == NULL) { 1361 TRAP_ERROR(); 1362 ng_destroy_hook(hook); /* XXX check ref counts so far */ 1363 NG_HOOK_UNREF(hook); /* including our ref */ 1364 return (ENOMEM); 1365 } 1366 hook2->hk_refs = 1; /* start with a reference for us. */ 1367 hook2->hk_flags = HK_INVALID; 1368 hook2->hk_peer = hook; /* Link the two together */ 1369 hook->hk_peer = hook2; 1370 NG_HOOK_REF(hook); /* Add a ref for the peer to each*/ 1371 NG_HOOK_REF(hook2); 1372 hook2->hk_node = &ng_deadnode; 1373 strlcpy(NG_HOOK_NAME(hook2), name2, NG_HOOKSIZ); 1374 1375 /* 1376 * Queue the function above. 1377 * Procesing continues in that function in the lock context of 1378 * the other node. 1379 */ 1380 ng_send_fn(node2, hook2, &ng_con_part2, NULL, 0); 1381 1382 NG_HOOK_UNREF(hook); /* Let each hook go if it wants to */ 1383 NG_HOOK_UNREF(hook2); 1384 return (0); 1385 } 1386 1387 /* 1388 * Make a peer and connect. 1389 * We assume that the local node is locked. 1390 * The new node probably doesn't need a lock until 1391 * it has a hook, because it cannot really have any work until then, 1392 * but we should think about it a bit more. 1393 * 1394 * The problem may come if the other node also fires up 1395 * some hardware or a timer or some other source of activation, 1396 * also it may already get a command msg via it's ID. 1397 * 1398 * We could use the same method as ng_con_nodes() but we'd have 1399 * to add ability to remove the node when failing. (Not hard, just 1400 * make arg1 point to the node to remove). 1401 * Unless of course we just ignore failure to connect and leave 1402 * an unconnected node? 1403 */ 1404 static int 1405 ng_mkpeer(node_p node, const char *name, const char *name2, char *type) 1406 { 1407 node_p node2; 1408 hook_p hook1, hook2; 1409 int error; 1410 1411 if ((error = ng_make_node(type, &node2))) { 1412 return (error); 1413 } 1414 1415 if ((error = ng_add_hook(node, name, &hook1))) { /* gives us a ref */ 1416 ng_rmnode(node2, NULL, NULL, 0); 1417 return (error); 1418 } 1419 1420 if ((error = ng_add_hook(node2, name2, &hook2))) { 1421 ng_rmnode(node2, NULL, NULL, 0); 1422 ng_destroy_hook(hook1); 1423 NG_HOOK_UNREF(hook1); 1424 return (error); 1425 } 1426 1427 /* 1428 * Actually link the two hooks together. 1429 */ 1430 hook1->hk_peer = hook2; 1431 hook2->hk_peer = hook1; 1432 1433 /* Each hook is referenced by the other */ 1434 NG_HOOK_REF(hook1); 1435 NG_HOOK_REF(hook2); 1436 1437 /* Give each node the opportunity to veto the pending connection */ 1438 if (hook1->hk_node->nd_type->connect) { 1439 error = (*hook1->hk_node->nd_type->connect) (hook1); 1440 } 1441 1442 if ((error == 0) && hook2->hk_node->nd_type->connect) { 1443 error = (*hook2->hk_node->nd_type->connect) (hook2); 1444 1445 } 1446 1447 /* 1448 * drop the references we were holding on the two hooks. 1449 */ 1450 if (error) { 1451 ng_destroy_hook(hook2); /* also zaps hook1 */ 1452 ng_rmnode(node2, NULL, NULL, 0); 1453 } else { 1454 /* As a last act, allow the hooks to be used */ 1455 hook1->hk_flags &= ~HK_INVALID; 1456 hook2->hk_flags &= ~HK_INVALID; 1457 } 1458 NG_HOOK_UNREF(hook1); 1459 NG_HOOK_UNREF(hook2); 1460 return (error); 1461 } 1462 1463 /************************************************************************ 1464 Utility routines to send self messages 1465 ************************************************************************/ 1466 1467 /* Shut this node down as soon as everyone is clear of it */ 1468 /* Should add arg "immediatly" to jump the queue */ 1469 int 1470 ng_rmnode_self(node_p node) 1471 { 1472 int error; 1473 1474 if (node == &ng_deadnode) 1475 return (0); 1476 node->nd_flags |= NGF_INVALID; 1477 if (node->nd_flags & NGF_CLOSING) 1478 return (0); 1479 1480 error = ng_send_fn(node, NULL, &ng_rmnode, NULL, 0); 1481 return (error); 1482 } 1483 1484 static void 1485 ng_rmhook_part2(node_p node, hook_p hook, void *arg1, int arg2) 1486 { 1487 ng_destroy_hook(hook); 1488 return ; 1489 } 1490 1491 int 1492 ng_rmhook_self(hook_p hook) 1493 { 1494 int error; 1495 node_p node = NG_HOOK_NODE(hook); 1496 1497 if (node == &ng_deadnode) 1498 return (0); 1499 1500 error = ng_send_fn(node, hook, &ng_rmhook_part2, NULL, 0); 1501 return (error); 1502 } 1503 1504 /*********************************************************************** 1505 * Parse and verify a string of the form: <NODE:><PATH> 1506 * 1507 * Such a string can refer to a specific node or a specific hook 1508 * on a specific node, depending on how you look at it. In the 1509 * latter case, the PATH component must not end in a dot. 1510 * 1511 * Both <NODE:> and <PATH> are optional. The <PATH> is a string 1512 * of hook names separated by dots. This breaks out the original 1513 * string, setting *nodep to "NODE" (or NULL if none) and *pathp 1514 * to "PATH" (or NULL if degenerate). Also, *hookp will point to 1515 * the final hook component of <PATH>, if any, otherwise NULL. 1516 * 1517 * This returns -1 if the path is malformed. The char ** are optional. 1518 ***********************************************************************/ 1519 int 1520 ng_path_parse(char *addr, char **nodep, char **pathp, char **hookp) 1521 { 1522 char *node, *path, *hook; 1523 int k; 1524 1525 /* 1526 * Extract absolute NODE, if any 1527 */ 1528 for (path = addr; *path && *path != ':'; path++); 1529 if (*path) { 1530 node = addr; /* Here's the NODE */ 1531 *path++ = '\0'; /* Here's the PATH */ 1532 1533 /* Node name must not be empty */ 1534 if (!*node) 1535 return -1; 1536 1537 /* A name of "." is OK; otherwise '.' not allowed */ 1538 if (strcmp(node, ".") != 0) { 1539 for (k = 0; node[k]; k++) 1540 if (node[k] == '.') 1541 return -1; 1542 } 1543 } else { 1544 node = NULL; /* No absolute NODE */ 1545 path = addr; /* Here's the PATH */ 1546 } 1547 1548 /* Snoop for illegal characters in PATH */ 1549 for (k = 0; path[k]; k++) 1550 if (path[k] == ':') 1551 return -1; 1552 1553 /* Check for no repeated dots in PATH */ 1554 for (k = 0; path[k]; k++) 1555 if (path[k] == '.' && path[k + 1] == '.') 1556 return -1; 1557 1558 /* Remove extra (degenerate) dots from beginning or end of PATH */ 1559 if (path[0] == '.') 1560 path++; 1561 if (*path && path[strlen(path) - 1] == '.') 1562 path[strlen(path) - 1] = 0; 1563 1564 /* If PATH has a dot, then we're not talking about a hook */ 1565 if (*path) { 1566 for (hook = path, k = 0; path[k]; k++) 1567 if (path[k] == '.') { 1568 hook = NULL; 1569 break; 1570 } 1571 } else 1572 path = hook = NULL; 1573 1574 /* Done */ 1575 if (nodep) 1576 *nodep = node; 1577 if (pathp) 1578 *pathp = path; 1579 if (hookp) 1580 *hookp = hook; 1581 return (0); 1582 } 1583 1584 /* 1585 * Given a path, which may be absolute or relative, and a starting node, 1586 * return the destination node. 1587 */ 1588 int 1589 ng_path2noderef(node_p here, const char *address, 1590 node_p *destp, hook_p *lasthook) 1591 { 1592 char fullpath[NG_PATHSIZ]; 1593 char *nodename, *path, pbuf[2]; 1594 node_p node, oldnode; 1595 char *cp; 1596 hook_p hook = NULL; 1597 1598 /* Initialize */ 1599 if (destp == NULL) { 1600 TRAP_ERROR(); 1601 return EINVAL; 1602 } 1603 *destp = NULL; 1604 1605 /* Make a writable copy of address for ng_path_parse() */ 1606 strncpy(fullpath, address, sizeof(fullpath) - 1); 1607 fullpath[sizeof(fullpath) - 1] = '\0'; 1608 1609 /* Parse out node and sequence of hooks */ 1610 if (ng_path_parse(fullpath, &nodename, &path, NULL) < 0) { 1611 TRAP_ERROR(); 1612 return EINVAL; 1613 } 1614 if (path == NULL) { 1615 pbuf[0] = '.'; /* Needs to be writable */ 1616 pbuf[1] = '\0'; 1617 path = pbuf; 1618 } 1619 1620 /* 1621 * For an absolute address, jump to the starting node. 1622 * Note that this holds a reference on the node for us. 1623 * Don't forget to drop the reference if we don't need it. 1624 */ 1625 if (nodename) { 1626 node = ng_name2noderef(here, nodename); 1627 if (node == NULL) { 1628 TRAP_ERROR(); 1629 return (ENOENT); 1630 } 1631 } else { 1632 if (here == NULL) { 1633 TRAP_ERROR(); 1634 return (EINVAL); 1635 } 1636 node = here; 1637 NG_NODE_REF(node); 1638 } 1639 1640 /* 1641 * Now follow the sequence of hooks 1642 * XXX 1643 * We actually cannot guarantee that the sequence 1644 * is not being demolished as we crawl along it 1645 * without extra-ordinary locking etc. 1646 * So this is a bit dodgy to say the least. 1647 * We can probably hold up some things by holding 1648 * the nodelist mutex for the time of this 1649 * crawl if we wanted.. At least that way we wouldn't have to 1650 * worry about the nodes dissappearing, but the hooks would still 1651 * be a problem. 1652 */ 1653 for (cp = path; node != NULL && *cp != '\0'; ) { 1654 char *segment; 1655 1656 /* 1657 * Break out the next path segment. Replace the dot we just 1658 * found with a NUL; "cp" points to the next segment (or the 1659 * NUL at the end). 1660 */ 1661 for (segment = cp; *cp != '\0'; cp++) { 1662 if (*cp == '.') { 1663 *cp++ = '\0'; 1664 break; 1665 } 1666 } 1667 1668 /* Empty segment */ 1669 if (*segment == '\0') 1670 continue; 1671 1672 /* We have a segment, so look for a hook by that name */ 1673 hook = ng_findhook(node, segment); 1674 1675 /* Can't get there from here... */ 1676 if (hook == NULL 1677 || NG_HOOK_PEER(hook) == NULL 1678 || NG_HOOK_NOT_VALID(hook) 1679 || NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook))) { 1680 TRAP_ERROR(); 1681 NG_NODE_UNREF(node); 1682 #if 0 1683 printf("hooknotvalid %s %s %d %d %d %d ", 1684 path, 1685 segment, 1686 hook == NULL, 1687 NG_HOOK_PEER(hook) == NULL, 1688 NG_HOOK_NOT_VALID(hook), 1689 NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook))); 1690 #endif 1691 return (ENOENT); 1692 } 1693 1694 /* 1695 * Hop on over to the next node 1696 * XXX 1697 * Big race conditions here as hooks and nodes go away 1698 * *** Idea.. store an ng_ID_t in each hook and use that 1699 * instead of the direct hook in this crawl? 1700 */ 1701 oldnode = node; 1702 if ((node = NG_PEER_NODE(hook))) 1703 NG_NODE_REF(node); /* XXX RACE */ 1704 NG_NODE_UNREF(oldnode); /* XXX another race */ 1705 if (NG_NODE_NOT_VALID(node)) { 1706 NG_NODE_UNREF(node); /* XXX more races */ 1707 node = NULL; 1708 } 1709 } 1710 1711 /* If node somehow missing, fail here (probably this is not needed) */ 1712 if (node == NULL) { 1713 TRAP_ERROR(); 1714 return (ENXIO); 1715 } 1716 1717 /* Done */ 1718 *destp = node; 1719 if (lasthook != NULL) 1720 *lasthook = (hook ? NG_HOOK_PEER(hook) : NULL); 1721 return (0); 1722 } 1723 1724 /***************************************************************\ 1725 * Input queue handling. 1726 * All activities are submitted to the node via the input queue 1727 * which implements a multiple-reader/single-writer gate. 1728 * Items which cannot be handled immeditly are queued. 1729 * 1730 * read-write queue locking inline functions * 1731 \***************************************************************/ 1732 1733 static __inline item_p ng_dequeue(struct ng_queue * ngq, int *rw); 1734 static __inline item_p ng_acquire_read(struct ng_queue * ngq, 1735 item_p item); 1736 static __inline item_p ng_acquire_write(struct ng_queue * ngq, 1737 item_p item); 1738 static __inline void ng_leave_read(struct ng_queue * ngq); 1739 static __inline void ng_leave_write(struct ng_queue * ngq); 1740 static __inline void ng_queue_rw(struct ng_queue * ngq, 1741 item_p item, int rw); 1742 1743 /* 1744 * Definition of the bits fields in the ng_queue flag word. 1745 * Defined here rather than in netgraph.h because no-one should fiddle 1746 * with them. 1747 * 1748 * The ordering here may be important! don't shuffle these. 1749 */ 1750 /*- 1751 Safety Barrier--------+ (adjustable to suit taste) (not used yet) 1752 | 1753 V 1754 +-------+-------+-------+-------+-------+-------+-------+-------+ 1755 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 1756 | |A|c|t|i|v|e| |R|e|a|d|e|r| |C|o|u|n|t| | | | | | | | | |P|A| 1757 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |O|W| 1758 +-------+-------+-------+-------+-------+-------+-------+-------+ 1759 \___________________________ ____________________________/ | | 1760 V | | 1761 [active reader count] | | 1762 | | 1763 Operation Pending -------------------------------+ | 1764 | 1765 Active Writer ---------------------------------------+ 1766 1767 1768 */ 1769 #define WRITER_ACTIVE 0x00000001 1770 #define OP_PENDING 0x00000002 1771 #define READER_INCREMENT 0x00000004 1772 #define READER_MASK 0xfffffffc /* Not valid if WRITER_ACTIVE is set */ 1773 #define SAFETY_BARRIER 0x00100000 /* 128K items queued should be enough */ 1774 1775 /* Defines of more elaborate states on the queue */ 1776 /* Mask of bits a new read cares about */ 1777 #define NGQ_RMASK (WRITER_ACTIVE|OP_PENDING) 1778 1779 /* Mask of bits a new write cares about */ 1780 #define NGQ_WMASK (NGQ_RMASK|READER_MASK) 1781 1782 /* Test to decide if there is something on the queue. */ 1783 #define QUEUE_ACTIVE(QP) ((QP)->q_flags & OP_PENDING) 1784 1785 /* How to decide what the next queued item is. */ 1786 #define HEAD_IS_READER(QP) NGI_QUEUED_READER((QP)->queue) 1787 #define HEAD_IS_WRITER(QP) NGI_QUEUED_WRITER((QP)->queue) /* notused */ 1788 1789 /* Read the status to decide if the next item on the queue can now run. */ 1790 #define QUEUED_READER_CAN_PROCEED(QP) \ 1791 (((QP)->q_flags & (NGQ_RMASK & ~OP_PENDING)) == 0) 1792 #define QUEUED_WRITER_CAN_PROCEED(QP) \ 1793 (((QP)->q_flags & (NGQ_WMASK & ~OP_PENDING)) == 0) 1794 1795 /* Is there a chance of getting ANY work off the queue? */ 1796 #define NEXT_QUEUED_ITEM_CAN_PROCEED(QP) \ 1797 (QUEUE_ACTIVE(QP) && \ 1798 ((HEAD_IS_READER(QP)) ? QUEUED_READER_CAN_PROCEED(QP) : \ 1799 QUEUED_WRITER_CAN_PROCEED(QP))) 1800 1801 1802 #define NGQRW_R 0 1803 #define NGQRW_W 1 1804 1805 /* 1806 * Taking into account the current state of the queue and node, possibly take 1807 * the next entry off the queue and return it. Return NULL if there was 1808 * nothing we could return, either because there really was nothing there, or 1809 * because the node was in a state where it cannot yet process the next item 1810 * on the queue. 1811 * 1812 * This MUST MUST MUST be called with the mutex held. 1813 */ 1814 static __inline item_p 1815 ng_dequeue(struct ng_queue *ngq, int *rw) 1816 { 1817 item_p item; 1818 u_int add_arg; 1819 1820 mtx_assert(&ngq->q_mtx, MA_OWNED); 1821 /* 1822 * If there is nothing queued, then just return. 1823 * No point in continuing. 1824 * XXXGL: assert this? 1825 */ 1826 if (!QUEUE_ACTIVE(ngq)) { 1827 CTR4(KTR_NET, "%20s: node [%x] (%p) queue empty; " 1828 "queue flags 0x%lx", __func__, 1829 ngq->q_node->nd_ID, ngq->q_node, ngq->q_flags); 1830 return (NULL); 1831 } 1832 1833 /* 1834 * From here, we can assume there is a head item. 1835 * We need to find out what it is and if it can be dequeued, given 1836 * the current state of the node. 1837 */ 1838 if (HEAD_IS_READER(ngq)) { 1839 if (!QUEUED_READER_CAN_PROCEED(ngq)) { 1840 /* 1841 * It's a reader but we can't use it. 1842 * We are stalled so make sure we don't 1843 * get called again until something changes. 1844 */ 1845 ng_worklist_remove(ngq->q_node); 1846 CTR4(KTR_NET, "%20s: node [%x] (%p) queued reader " 1847 "can't proceed; queue flags 0x%lx", __func__, 1848 ngq->q_node->nd_ID, ngq->q_node, ngq->q_flags); 1849 return (NULL); 1850 } 1851 /* 1852 * Head of queue is a reader and we have no write active. 1853 * We don't care how many readers are already active. 1854 * Add the correct increment for the reader count. 1855 */ 1856 add_arg = READER_INCREMENT; 1857 *rw = NGQRW_R; 1858 } else if (QUEUED_WRITER_CAN_PROCEED(ngq)) { 1859 /* 1860 * There is a pending write, no readers and no active writer. 1861 * This means we can go ahead with the pending writer. Note 1862 * the fact that we now have a writer, ready for when we take 1863 * it off the queue. 1864 * 1865 * We don't need to worry about a possible collision with the 1866 * fasttrack reader. 1867 * 1868 * The fasttrack thread may take a long time to discover that we 1869 * are running so we would have an inconsistent state in the 1870 * flags for a while. Since we ignore the reader count 1871 * entirely when the WRITER_ACTIVE flag is set, this should 1872 * not matter (in fact it is defined that way). If it tests 1873 * the flag before this operation, the OP_PENDING flag 1874 * will make it fail, and if it tests it later, the 1875 * WRITER_ACTIVE flag will do the same. If it is SO slow that 1876 * we have actually completed the operation, and neither flag 1877 * is set by the time that it tests the flags, then it is 1878 * actually ok for it to continue. If it completes and we've 1879 * finished and the read pending is set it still fails. 1880 * 1881 * So we can just ignore it, as long as we can ensure that the 1882 * transition from WRITE_PENDING state to the WRITER_ACTIVE 1883 * state is atomic. 1884 * 1885 * After failing, first it will be held back by the mutex, then 1886 * when it can proceed, it will queue its request, then it 1887 * would arrive at this function. Usually it will have to 1888 * leave empty handed because the ACTIVE WRITER bit will be 1889 * set. 1890 * 1891 * Adjust the flags for the new active writer. 1892 */ 1893 add_arg = WRITER_ACTIVE; 1894 *rw = NGQRW_W; 1895 /* 1896 * We want to write "active writer, no readers " Now go make 1897 * it true. In fact there may be a number in the readers 1898 * count but we know it is not true and will be fixed soon. 1899 * We will fix the flags for the next pending entry in a 1900 * moment. 1901 */ 1902 } else { 1903 /* 1904 * We can't dequeue anything.. return and say so. Probably we 1905 * have a write pending and the readers count is non zero. If 1906 * we got here because a reader hit us just at the wrong 1907 * moment with the fasttrack code, and put us in a strange 1908 * state, then it will be coming through in just a moment, 1909 * (just as soon as we release the mutex) and keep things 1910 * moving. 1911 * Make sure we remove ourselves from the work queue. It 1912 * would be a waste of effort to do all this again. 1913 */ 1914 ng_worklist_remove(ngq->q_node); 1915 CTR4(KTR_NET, "%20s: node [%x] (%p) can't dequeue anything; " 1916 "queue flags 0x%lx", __func__, 1917 ngq->q_node->nd_ID, ngq->q_node, ngq->q_flags); 1918 return (NULL); 1919 } 1920 1921 /* 1922 * Now we dequeue the request (whatever it may be) and correct the 1923 * pending flags and the next and last pointers. 1924 */ 1925 item = ngq->queue; 1926 ngq->queue = item->el_next; 1927 CTR6(KTR_NET, "%20s: node [%x] (%p) dequeued item %p with flags 0x%lx; " 1928 "queue flags 0x%lx", __func__, 1929 ngq->q_node->nd_ID,ngq->q_node, item, item->el_flags, ngq->q_flags); 1930 if (ngq->last == &(item->el_next)) { 1931 /* 1932 * that was the last entry in the queue so set the 'last 1933 * pointer up correctly and make sure the pending flag is 1934 * clear. 1935 */ 1936 add_arg += -OP_PENDING; 1937 ngq->last = &(ngq->queue); 1938 /* 1939 * Whatever flag was set will be cleared and 1940 * the new acive field will be set by the add as well, 1941 * so we don't need to change add_arg. 1942 * But we know we don't need to be on the work list. 1943 */ 1944 atomic_add_long(&ngq->q_flags, add_arg); 1945 ng_worklist_remove(ngq->q_node); 1946 } else { 1947 /* 1948 * Since there is still something on the queue 1949 * we don't need to change the PENDING flag. 1950 */ 1951 atomic_add_long(&ngq->q_flags, add_arg); 1952 /* 1953 * If we see more doable work, make sure we are 1954 * on the work queue. 1955 */ 1956 if (NEXT_QUEUED_ITEM_CAN_PROCEED(ngq)) { 1957 ng_setisr(ngq->q_node); 1958 } 1959 } 1960 CTR6(KTR_NET, "%20s: node [%x] (%p) returning item %p as %s; " 1961 "queue flags 0x%lx", __func__, 1962 ngq->q_node->nd_ID, ngq->q_node, item, *rw ? "WRITER" : "READER" , 1963 ngq->q_flags); 1964 return (item); 1965 } 1966 1967 /* 1968 * Queue a packet to be picked up by someone else. 1969 * We really don't care who, but we can't or don't want to hang around 1970 * to process it ourselves. We are probably an interrupt routine.. 1971 * If the queue could be run, flag the netisr handler to start. 1972 */ 1973 static __inline void 1974 ng_queue_rw(struct ng_queue * ngq, item_p item, int rw) 1975 { 1976 mtx_assert(&ngq->q_mtx, MA_OWNED); 1977 1978 if (rw == NGQRW_W) 1979 NGI_SET_WRITER(item); 1980 else 1981 NGI_SET_READER(item); 1982 item->el_next = NULL; /* maybe not needed */ 1983 *ngq->last = item; 1984 CTR5(KTR_NET, "%20s: node [%x] (%p) queued item %p as %s", __func__, 1985 ngq->q_node->nd_ID, ngq->q_node, item, rw ? "WRITER" : "READER" ); 1986 /* 1987 * If it was the first item in the queue then we need to 1988 * set the last pointer and the type flags. 1989 */ 1990 if (ngq->last == &(ngq->queue)) { 1991 atomic_add_long(&ngq->q_flags, OP_PENDING); 1992 CTR3(KTR_NET, "%20s: node [%x] (%p) set OP_PENDING", __func__, 1993 ngq->q_node->nd_ID, ngq->q_node); 1994 } 1995 1996 ngq->last = &(item->el_next); 1997 /* 1998 * We can take the worklist lock with the node locked 1999 * BUT NOT THE REVERSE! 2000 */ 2001 if (NEXT_QUEUED_ITEM_CAN_PROCEED(ngq)) 2002 ng_setisr(ngq->q_node); 2003 } 2004 2005 2006 /* 2007 * This function 'cheats' in that it first tries to 'grab' the use of the 2008 * node, without going through the mutex. We can do this becasue of the 2009 * semantics of the lock. The semantics include a clause that says that the 2010 * value of the readers count is invalid if the WRITER_ACTIVE flag is set. It 2011 * also says that the WRITER_ACTIVE flag cannot be set if the readers count 2012 * is not zero. Note that this talks about what is valid to SET the 2013 * WRITER_ACTIVE flag, because from the moment it is set, the value if the 2014 * reader count is immaterial, and not valid. The two 'pending' flags have a 2015 * similar effect, in that If they are orthogonal to the two active fields in 2016 * how they are set, but if either is set, the attempted 'grab' need to be 2017 * backed out because there is earlier work, and we maintain ordering in the 2018 * queue. The result of this is that the reader request can try obtain use of 2019 * the node with only a single atomic addition, and without any of the mutex 2020 * overhead. If this fails the operation degenerates to the same as for other 2021 * cases. 2022 * 2023 */ 2024 static __inline item_p 2025 ng_acquire_read(struct ng_queue *ngq, item_p item) 2026 { 2027 KASSERT(ngq != &ng_deadnode.nd_input_queue, 2028 ("%s: working on deadnode", __func__)); 2029 2030 /* ######### Hack alert ######### */ 2031 atomic_add_long(&ngq->q_flags, READER_INCREMENT); 2032 if ((ngq->q_flags & NGQ_RMASK) == 0) { 2033 /* Successfully grabbed node */ 2034 CTR4(KTR_NET, "%20s: node [%x] (%p) fast acquired item %p", 2035 __func__, ngq->q_node->nd_ID, ngq->q_node, item); 2036 return (item); 2037 } 2038 /* undo the damage if we didn't succeed */ 2039 atomic_subtract_long(&ngq->q_flags, READER_INCREMENT); 2040 2041 /* ######### End Hack alert ######### */ 2042 mtx_lock_spin((&ngq->q_mtx)); 2043 /* 2044 * Try again. Another processor (or interrupt for that matter) may 2045 * have removed the last queued item that was stopping us from 2046 * running, between the previous test, and the moment that we took 2047 * the mutex. (Or maybe a writer completed.) 2048 * Even if another fast-track reader hits during this period 2049 * we don't care as multiple readers is OK. 2050 */ 2051 if ((ngq->q_flags & NGQ_RMASK) == 0) { 2052 atomic_add_long(&ngq->q_flags, READER_INCREMENT); 2053 mtx_unlock_spin((&ngq->q_mtx)); 2054 CTR4(KTR_NET, "%20s: node [%x] (%p) slow acquired item %p", 2055 __func__, ngq->q_node->nd_ID, ngq->q_node, item); 2056 return (item); 2057 } 2058 2059 /* 2060 * and queue the request for later. 2061 */ 2062 ng_queue_rw(ngq, item, NGQRW_R); 2063 mtx_unlock_spin(&(ngq->q_mtx)); 2064 2065 return (NULL); 2066 } 2067 2068 static __inline item_p 2069 ng_acquire_write(struct ng_queue *ngq, item_p item) 2070 { 2071 KASSERT(ngq != &ng_deadnode.nd_input_queue, 2072 ("%s: working on deadnode", __func__)); 2073 2074 restart: 2075 mtx_lock_spin(&(ngq->q_mtx)); 2076 /* 2077 * If there are no readers, no writer, and no pending packets, then 2078 * we can just go ahead. In all other situations we need to queue the 2079 * request 2080 */ 2081 if ((ngq->q_flags & NGQ_WMASK) == 0) { 2082 /* collision could happen *HERE* */ 2083 atomic_add_long(&ngq->q_flags, WRITER_ACTIVE); 2084 mtx_unlock_spin((&ngq->q_mtx)); 2085 if (ngq->q_flags & READER_MASK) { 2086 /* Collision with fast-track reader */ 2087 atomic_subtract_long(&ngq->q_flags, WRITER_ACTIVE); 2088 goto restart; 2089 } 2090 CTR4(KTR_NET, "%20s: node [%x] (%p) acquired item %p", 2091 __func__, ngq->q_node->nd_ID, ngq->q_node, item); 2092 return (item); 2093 } 2094 2095 /* 2096 * and queue the request for later. 2097 */ 2098 ng_queue_rw(ngq, item, NGQRW_W); 2099 mtx_unlock_spin(&(ngq->q_mtx)); 2100 2101 return (NULL); 2102 } 2103 2104 static __inline void 2105 ng_leave_read(struct ng_queue *ngq) 2106 { 2107 atomic_subtract_long(&ngq->q_flags, READER_INCREMENT); 2108 } 2109 2110 static __inline void 2111 ng_leave_write(struct ng_queue *ngq) 2112 { 2113 atomic_subtract_long(&ngq->q_flags, WRITER_ACTIVE); 2114 } 2115 2116 static void 2117 ng_flush_input_queue(struct ng_queue * ngq) 2118 { 2119 item_p item; 2120 2121 mtx_lock_spin(&ngq->q_mtx); 2122 while (ngq->queue) { 2123 item = ngq->queue; 2124 ngq->queue = item->el_next; 2125 if (ngq->last == &(item->el_next)) { 2126 ngq->last = &(ngq->queue); 2127 atomic_add_long(&ngq->q_flags, -OP_PENDING); 2128 } 2129 mtx_unlock_spin(&ngq->q_mtx); 2130 2131 /* If the item is supplying a callback, call it with an error */ 2132 if (item->apply != NULL) { 2133 (item->apply)(item->context, ENOENT); 2134 item->apply = NULL; 2135 } 2136 NG_FREE_ITEM(item); 2137 mtx_lock_spin(&ngq->q_mtx); 2138 } 2139 /* 2140 * Take us off the work queue if we are there. 2141 * We definatly have no work to be done. 2142 */ 2143 ng_worklist_remove(ngq->q_node); 2144 mtx_unlock_spin(&ngq->q_mtx); 2145 } 2146 2147 /*********************************************************************** 2148 * Externally visible method for sending or queueing messages or data. 2149 ***********************************************************************/ 2150 2151 /* 2152 * The module code should have filled out the item correctly by this stage: 2153 * Common: 2154 * reference to destination node. 2155 * Reference to destination rcv hook if relevant. 2156 * Data: 2157 * pointer to mbuf 2158 * Control_Message: 2159 * pointer to msg. 2160 * ID of original sender node. (return address) 2161 * Function: 2162 * Function pointer 2163 * void * argument 2164 * integer argument 2165 * 2166 * The nodes have several routines and macros to help with this task: 2167 */ 2168 2169 int 2170 ng_snd_item(item_p item, int flags) 2171 { 2172 hook_p hook = NGI_HOOK(item); 2173 node_p node = NGI_NODE(item); 2174 int queue, rw; 2175 struct ng_queue * ngq = &node->nd_input_queue; 2176 int error = 0; 2177 2178 #ifdef NETGRAPH_DEBUG 2179 _ngi_check(item, __FILE__, __LINE__); 2180 #endif 2181 2182 queue = (flags & NG_QUEUE) ? 1 : 0; 2183 2184 if (item == NULL) { 2185 TRAP_ERROR(); 2186 return (EINVAL); /* failed to get queue element */ 2187 } 2188 if (node == NULL) { 2189 NG_FREE_ITEM(item); 2190 TRAP_ERROR(); 2191 return (EINVAL); /* No address */ 2192 } 2193 switch(item->el_flags & NGQF_TYPE) { 2194 case NGQF_DATA: 2195 /* 2196 * DATA MESSAGE 2197 * Delivered to a node via a non-optional hook. 2198 * Both should be present in the item even though 2199 * the node is derivable from the hook. 2200 * References are held on both by the item. 2201 */ 2202 2203 /* Protect nodes from sending NULL pointers 2204 * to each other 2205 */ 2206 if (NGI_M(item) == NULL) 2207 return (EINVAL); 2208 2209 CHECK_DATA_MBUF(NGI_M(item)); 2210 if (hook == NULL) { 2211 NG_FREE_ITEM(item); 2212 TRAP_ERROR(); 2213 return(EINVAL); 2214 } 2215 if ((NG_HOOK_NOT_VALID(hook)) 2216 || (NG_NODE_NOT_VALID(NG_HOOK_NODE(hook)))) { 2217 NG_FREE_ITEM(item); 2218 return (ENOTCONN); 2219 } 2220 if ((hook->hk_flags & HK_QUEUE)) { 2221 queue = 1; 2222 } 2223 break; 2224 case NGQF_MESG: 2225 /* 2226 * CONTROL MESSAGE 2227 * Delivered to a node. 2228 * Hook is optional. 2229 * References are held by the item on the node and 2230 * the hook if it is present. 2231 */ 2232 if (hook && (hook->hk_flags & HK_QUEUE)) { 2233 queue = 1; 2234 } 2235 break; 2236 case NGQF_FN: 2237 break; 2238 default: 2239 NG_FREE_ITEM(item); 2240 TRAP_ERROR(); 2241 return (EINVAL); 2242 } 2243 switch(item->el_flags & NGQF_RW) { 2244 case NGQF_READER: 2245 rw = NGQRW_R; 2246 break; 2247 case NGQF_WRITER: 2248 rw = NGQRW_W; 2249 break; 2250 default: 2251 panic("%s: invalid item flags %lx", __func__, item->el_flags); 2252 } 2253 2254 /* 2255 * If the node specifies single threading, force writer semantics. 2256 * Similarly, the node may say one hook always produces writers. 2257 * These are overrides. 2258 */ 2259 if ((node->nd_flags & NGF_FORCE_WRITER) 2260 || (hook && (hook->hk_flags & HK_FORCE_WRITER))) 2261 rw = NGQRW_W; 2262 2263 if (queue) { 2264 /* Put it on the queue for that node*/ 2265 #ifdef NETGRAPH_DEBUG 2266 _ngi_check(item, __FILE__, __LINE__); 2267 #endif 2268 mtx_lock_spin(&(ngq->q_mtx)); 2269 ng_queue_rw(ngq, item, rw); 2270 mtx_unlock_spin(&(ngq->q_mtx)); 2271 2272 if (flags & NG_PROGRESS) 2273 return (EINPROGRESS); 2274 else 2275 return (0); 2276 } 2277 2278 /* 2279 * We already decided how we will be queueud or treated. 2280 * Try get the appropriate operating permission. 2281 */ 2282 if (rw == NGQRW_R) 2283 item = ng_acquire_read(ngq, item); 2284 else 2285 item = ng_acquire_write(ngq, item); 2286 2287 2288 if (item == NULL) { 2289 if (flags & NG_PROGRESS) 2290 return (EINPROGRESS); 2291 else 2292 return (0); 2293 } 2294 2295 #ifdef NETGRAPH_DEBUG 2296 _ngi_check(item, __FILE__, __LINE__); 2297 #endif 2298 2299 NGI_GET_NODE(item, node); /* zaps stored node */ 2300 2301 error = ng_apply_item(node, item, rw); /* drops r/w lock when done */ 2302 2303 /* 2304 * If the node goes away when we remove the reference, 2305 * whatever we just did caused it.. whatever we do, DO NOT 2306 * access the node again! 2307 */ 2308 if (NG_NODE_UNREF(node) == 0) { 2309 return (error); 2310 } 2311 2312 mtx_lock_spin(&(ngq->q_mtx)); 2313 if (NEXT_QUEUED_ITEM_CAN_PROCEED(ngq)) 2314 ng_setisr(ngq->q_node); 2315 mtx_unlock_spin(&(ngq->q_mtx)); 2316 2317 return (error); 2318 } 2319 2320 /* 2321 * We have an item that was possibly queued somewhere. 2322 * It should contain all the information needed 2323 * to run it on the appropriate node/hook. 2324 */ 2325 static int 2326 ng_apply_item(node_p node, item_p item, int rw) 2327 { 2328 hook_p hook; 2329 int error = 0; 2330 ng_rcvdata_t *rcvdata; 2331 ng_rcvmsg_t *rcvmsg; 2332 ng_apply_t *apply = NULL; 2333 void *context = NULL; 2334 2335 NGI_GET_HOOK(item, hook); /* clears stored hook */ 2336 #ifdef NETGRAPH_DEBUG 2337 _ngi_check(item, __FILE__, __LINE__); 2338 #endif 2339 2340 /* 2341 * If the item has an "apply" callback, store it. 2342 * Clear item's callback immediately, to avoid an extra call if 2343 * the item is reused by the destination node. 2344 */ 2345 if (item->apply != NULL) { 2346 apply = item->apply; 2347 context = item->context; 2348 item->apply = NULL; 2349 } 2350 2351 switch (item->el_flags & NGQF_TYPE) { 2352 case NGQF_DATA: 2353 /* 2354 * Check things are still ok as when we were queued. 2355 */ 2356 if ((hook == NULL) 2357 || NG_HOOK_NOT_VALID(hook) 2358 || NG_NODE_NOT_VALID(node) ) { 2359 error = EIO; 2360 NG_FREE_ITEM(item); 2361 break; 2362 } 2363 /* 2364 * If no receive method, just silently drop it. 2365 * Give preference to the hook over-ride method 2366 */ 2367 if ((!(rcvdata = hook->hk_rcvdata)) 2368 && (!(rcvdata = NG_HOOK_NODE(hook)->nd_type->rcvdata))) { 2369 error = 0; 2370 NG_FREE_ITEM(item); 2371 break; 2372 } 2373 error = (*rcvdata)(hook, item); 2374 break; 2375 case NGQF_MESG: 2376 if (hook) { 2377 if (NG_HOOK_NOT_VALID(hook)) { 2378 /* 2379 * The hook has been zapped then we can't 2380 * use it. Immediatly drop its reference. 2381 * The message may not need it. 2382 */ 2383 NG_HOOK_UNREF(hook); 2384 hook = NULL; 2385 } 2386 } 2387 /* 2388 * Similarly, if the node is a zombie there is 2389 * nothing we can do with it, drop everything. 2390 */ 2391 if (NG_NODE_NOT_VALID(node)) { 2392 TRAP_ERROR(); 2393 error = EINVAL; 2394 NG_FREE_ITEM(item); 2395 } else { 2396 /* 2397 * Call the appropriate message handler for the object. 2398 * It is up to the message handler to free the message. 2399 * If it's a generic message, handle it generically, 2400 * otherwise call the type's message handler 2401 * (if it exists) 2402 * XXX (race). Remember that a queued message may 2403 * reference a node or hook that has just been 2404 * invalidated. It will exist as the queue code 2405 * is holding a reference, but.. 2406 */ 2407 2408 struct ng_mesg *msg = NGI_MSG(item); 2409 2410 /* 2411 * check if the generic handler owns it. 2412 */ 2413 if ((msg->header.typecookie == NGM_GENERIC_COOKIE) 2414 && ((msg->header.flags & NGF_RESP) == 0)) { 2415 error = ng_generic_msg(node, item, hook); 2416 break; 2417 } 2418 /* 2419 * Now see if there is a handler (hook or node specific) 2420 * in the target node. If none, silently discard. 2421 */ 2422 if (((!hook) || (!(rcvmsg = hook->hk_rcvmsg))) 2423 && (!(rcvmsg = node->nd_type->rcvmsg))) { 2424 TRAP_ERROR(); 2425 error = 0; 2426 NG_FREE_ITEM(item); 2427 break; 2428 } 2429 error = (*rcvmsg)(node, item, hook); 2430 } 2431 break; 2432 case NGQF_FN: 2433 /* 2434 * We have to implicitly trust the hook, 2435 * as some of these are used for system purposes 2436 * where the hook is invalid. In the case of 2437 * the shutdown message we allow it to hit 2438 * even if the node is invalid. 2439 */ 2440 if ((NG_NODE_NOT_VALID(node)) 2441 && (NGI_FN(item) != &ng_rmnode)) { 2442 TRAP_ERROR(); 2443 error = EINVAL; 2444 NG_FREE_ITEM(item); 2445 break; 2446 } 2447 (*NGI_FN(item))(node, hook, NGI_ARG1(item), NGI_ARG2(item)); 2448 NG_FREE_ITEM(item); 2449 break; 2450 2451 } 2452 /* 2453 * We held references on some of the resources 2454 * that we took from the item. Now that we have 2455 * finished doing everything, drop those references. 2456 */ 2457 if (hook) { 2458 NG_HOOK_UNREF(hook); 2459 } 2460 2461 if (rw == NGQRW_R) { 2462 ng_leave_read(&node->nd_input_queue); 2463 } else { 2464 ng_leave_write(&node->nd_input_queue); 2465 } 2466 2467 /* Apply callback. */ 2468 if (apply != NULL) 2469 (*apply)(context, error); 2470 2471 return (error); 2472 } 2473 2474 /*********************************************************************** 2475 * Implement the 'generic' control messages 2476 ***********************************************************************/ 2477 static int 2478 ng_generic_msg(node_p here, item_p item, hook_p lasthook) 2479 { 2480 int error = 0; 2481 struct ng_mesg *msg; 2482 struct ng_mesg *resp = NULL; 2483 2484 NGI_GET_MSG(item, msg); 2485 if (msg->header.typecookie != NGM_GENERIC_COOKIE) { 2486 TRAP_ERROR(); 2487 error = EINVAL; 2488 goto out; 2489 } 2490 switch (msg->header.cmd) { 2491 case NGM_SHUTDOWN: 2492 ng_rmnode(here, NULL, NULL, 0); 2493 break; 2494 case NGM_MKPEER: 2495 { 2496 struct ngm_mkpeer *const mkp = (struct ngm_mkpeer *) msg->data; 2497 2498 if (msg->header.arglen != sizeof(*mkp)) { 2499 TRAP_ERROR(); 2500 error = EINVAL; 2501 break; 2502 } 2503 mkp->type[sizeof(mkp->type) - 1] = '\0'; 2504 mkp->ourhook[sizeof(mkp->ourhook) - 1] = '\0'; 2505 mkp->peerhook[sizeof(mkp->peerhook) - 1] = '\0'; 2506 error = ng_mkpeer(here, mkp->ourhook, mkp->peerhook, mkp->type); 2507 break; 2508 } 2509 case NGM_CONNECT: 2510 { 2511 struct ngm_connect *const con = 2512 (struct ngm_connect *) msg->data; 2513 node_p node2; 2514 2515 if (msg->header.arglen != sizeof(*con)) { 2516 TRAP_ERROR(); 2517 error = EINVAL; 2518 break; 2519 } 2520 con->path[sizeof(con->path) - 1] = '\0'; 2521 con->ourhook[sizeof(con->ourhook) - 1] = '\0'; 2522 con->peerhook[sizeof(con->peerhook) - 1] = '\0'; 2523 /* Don't forget we get a reference.. */ 2524 error = ng_path2noderef(here, con->path, &node2, NULL); 2525 if (error) 2526 break; 2527 error = ng_con_nodes(here, con->ourhook, node2, con->peerhook); 2528 NG_NODE_UNREF(node2); 2529 break; 2530 } 2531 case NGM_NAME: 2532 { 2533 struct ngm_name *const nam = (struct ngm_name *) msg->data; 2534 2535 if (msg->header.arglen != sizeof(*nam)) { 2536 TRAP_ERROR(); 2537 error = EINVAL; 2538 break; 2539 } 2540 nam->name[sizeof(nam->name) - 1] = '\0'; 2541 error = ng_name_node(here, nam->name); 2542 break; 2543 } 2544 case NGM_RMHOOK: 2545 { 2546 struct ngm_rmhook *const rmh = (struct ngm_rmhook *) msg->data; 2547 hook_p hook; 2548 2549 if (msg->header.arglen != sizeof(*rmh)) { 2550 TRAP_ERROR(); 2551 error = EINVAL; 2552 break; 2553 } 2554 rmh->ourhook[sizeof(rmh->ourhook) - 1] = '\0'; 2555 if ((hook = ng_findhook(here, rmh->ourhook)) != NULL) 2556 ng_destroy_hook(hook); 2557 break; 2558 } 2559 case NGM_NODEINFO: 2560 { 2561 struct nodeinfo *ni; 2562 2563 NG_MKRESPONSE(resp, msg, sizeof(*ni), M_NOWAIT); 2564 if (resp == NULL) { 2565 error = ENOMEM; 2566 break; 2567 } 2568 2569 /* Fill in node info */ 2570 ni = (struct nodeinfo *) resp->data; 2571 if (NG_NODE_HAS_NAME(here)) 2572 strcpy(ni->name, NG_NODE_NAME(here)); 2573 strcpy(ni->type, here->nd_type->name); 2574 ni->id = ng_node2ID(here); 2575 ni->hooks = here->nd_numhooks; 2576 break; 2577 } 2578 case NGM_LISTHOOKS: 2579 { 2580 const int nhooks = here->nd_numhooks; 2581 struct hooklist *hl; 2582 struct nodeinfo *ni; 2583 hook_p hook; 2584 2585 /* Get response struct */ 2586 NG_MKRESPONSE(resp, msg, sizeof(*hl) 2587 + (nhooks * sizeof(struct linkinfo)), M_NOWAIT); 2588 if (resp == NULL) { 2589 error = ENOMEM; 2590 break; 2591 } 2592 hl = (struct hooklist *) resp->data; 2593 ni = &hl->nodeinfo; 2594 2595 /* Fill in node info */ 2596 if (NG_NODE_HAS_NAME(here)) 2597 strcpy(ni->name, NG_NODE_NAME(here)); 2598 strcpy(ni->type, here->nd_type->name); 2599 ni->id = ng_node2ID(here); 2600 2601 /* Cycle through the linked list of hooks */ 2602 ni->hooks = 0; 2603 LIST_FOREACH(hook, &here->nd_hooks, hk_hooks) { 2604 struct linkinfo *const link = &hl->link[ni->hooks]; 2605 2606 if (ni->hooks >= nhooks) { 2607 log(LOG_ERR, "%s: number of %s changed\n", 2608 __func__, "hooks"); 2609 break; 2610 } 2611 if (NG_HOOK_NOT_VALID(hook)) 2612 continue; 2613 strcpy(link->ourhook, NG_HOOK_NAME(hook)); 2614 strcpy(link->peerhook, NG_PEER_HOOK_NAME(hook)); 2615 if (NG_PEER_NODE_NAME(hook)[0] != '\0') 2616 strcpy(link->nodeinfo.name, 2617 NG_PEER_NODE_NAME(hook)); 2618 strcpy(link->nodeinfo.type, 2619 NG_PEER_NODE(hook)->nd_type->name); 2620 link->nodeinfo.id = ng_node2ID(NG_PEER_NODE(hook)); 2621 link->nodeinfo.hooks = NG_PEER_NODE(hook)->nd_numhooks; 2622 ni->hooks++; 2623 } 2624 break; 2625 } 2626 2627 case NGM_LISTNAMES: 2628 case NGM_LISTNODES: 2629 { 2630 const int unnamed = (msg->header.cmd == NGM_LISTNODES); 2631 struct namelist *nl; 2632 node_p node; 2633 int num = 0; 2634 2635 mtx_lock(&ng_nodelist_mtx); 2636 /* Count number of nodes */ 2637 LIST_FOREACH(node, &ng_nodelist, nd_nodes) { 2638 if (NG_NODE_IS_VALID(node) 2639 && (unnamed || NG_NODE_HAS_NAME(node))) { 2640 num++; 2641 } 2642 } 2643 mtx_unlock(&ng_nodelist_mtx); 2644 2645 /* Get response struct */ 2646 NG_MKRESPONSE(resp, msg, sizeof(*nl) 2647 + (num * sizeof(struct nodeinfo)), M_NOWAIT); 2648 if (resp == NULL) { 2649 error = ENOMEM; 2650 break; 2651 } 2652 nl = (struct namelist *) resp->data; 2653 2654 /* Cycle through the linked list of nodes */ 2655 nl->numnames = 0; 2656 mtx_lock(&ng_nodelist_mtx); 2657 LIST_FOREACH(node, &ng_nodelist, nd_nodes) { 2658 struct nodeinfo *const np = &nl->nodeinfo[nl->numnames]; 2659 2660 if (NG_NODE_NOT_VALID(node)) 2661 continue; 2662 if (!unnamed && (! NG_NODE_HAS_NAME(node))) 2663 continue; 2664 if (nl->numnames >= num) { 2665 log(LOG_ERR, "%s: number of %s changed\n", 2666 __func__, "nodes"); 2667 break; 2668 } 2669 if (NG_NODE_HAS_NAME(node)) 2670 strcpy(np->name, NG_NODE_NAME(node)); 2671 strcpy(np->type, node->nd_type->name); 2672 np->id = ng_node2ID(node); 2673 np->hooks = node->nd_numhooks; 2674 nl->numnames++; 2675 } 2676 mtx_unlock(&ng_nodelist_mtx); 2677 break; 2678 } 2679 2680 case NGM_LISTTYPES: 2681 { 2682 struct typelist *tl; 2683 struct ng_type *type; 2684 int num = 0; 2685 2686 mtx_lock(&ng_typelist_mtx); 2687 /* Count number of types */ 2688 LIST_FOREACH(type, &ng_typelist, types) { 2689 num++; 2690 } 2691 mtx_unlock(&ng_typelist_mtx); 2692 2693 /* Get response struct */ 2694 NG_MKRESPONSE(resp, msg, sizeof(*tl) 2695 + (num * sizeof(struct typeinfo)), M_NOWAIT); 2696 if (resp == NULL) { 2697 error = ENOMEM; 2698 break; 2699 } 2700 tl = (struct typelist *) resp->data; 2701 2702 /* Cycle through the linked list of types */ 2703 tl->numtypes = 0; 2704 mtx_lock(&ng_typelist_mtx); 2705 LIST_FOREACH(type, &ng_typelist, types) { 2706 struct typeinfo *const tp = &tl->typeinfo[tl->numtypes]; 2707 2708 if (tl->numtypes >= num) { 2709 log(LOG_ERR, "%s: number of %s changed\n", 2710 __func__, "types"); 2711 break; 2712 } 2713 strcpy(tp->type_name, type->name); 2714 tp->numnodes = type->refs - 1; /* don't count list */ 2715 tl->numtypes++; 2716 } 2717 mtx_unlock(&ng_typelist_mtx); 2718 break; 2719 } 2720 2721 case NGM_BINARY2ASCII: 2722 { 2723 int bufSize = 20 * 1024; /* XXX hard coded constant */ 2724 const struct ng_parse_type *argstype; 2725 const struct ng_cmdlist *c; 2726 struct ng_mesg *binary, *ascii; 2727 2728 /* Data area must contain a valid netgraph message */ 2729 binary = (struct ng_mesg *)msg->data; 2730 if (msg->header.arglen < sizeof(struct ng_mesg) || 2731 (msg->header.arglen - sizeof(struct ng_mesg) < 2732 binary->header.arglen)) { 2733 TRAP_ERROR(); 2734 error = EINVAL; 2735 break; 2736 } 2737 2738 /* Get a response message with lots of room */ 2739 NG_MKRESPONSE(resp, msg, sizeof(*ascii) + bufSize, M_NOWAIT); 2740 if (resp == NULL) { 2741 error = ENOMEM; 2742 break; 2743 } 2744 ascii = (struct ng_mesg *)resp->data; 2745 2746 /* Copy binary message header to response message payload */ 2747 bcopy(binary, ascii, sizeof(*binary)); 2748 2749 /* Find command by matching typecookie and command number */ 2750 for (c = here->nd_type->cmdlist; 2751 c != NULL && c->name != NULL; c++) { 2752 if (binary->header.typecookie == c->cookie 2753 && binary->header.cmd == c->cmd) 2754 break; 2755 } 2756 if (c == NULL || c->name == NULL) { 2757 for (c = ng_generic_cmds; c->name != NULL; c++) { 2758 if (binary->header.typecookie == c->cookie 2759 && binary->header.cmd == c->cmd) 2760 break; 2761 } 2762 if (c->name == NULL) { 2763 NG_FREE_MSG(resp); 2764 error = ENOSYS; 2765 break; 2766 } 2767 } 2768 2769 /* Convert command name to ASCII */ 2770 snprintf(ascii->header.cmdstr, sizeof(ascii->header.cmdstr), 2771 "%s", c->name); 2772 2773 /* Convert command arguments to ASCII */ 2774 argstype = (binary->header.flags & NGF_RESP) ? 2775 c->respType : c->mesgType; 2776 if (argstype == NULL) { 2777 *ascii->data = '\0'; 2778 } else { 2779 if ((error = ng_unparse(argstype, 2780 (u_char *)binary->data, 2781 ascii->data, bufSize)) != 0) { 2782 NG_FREE_MSG(resp); 2783 break; 2784 } 2785 } 2786 2787 /* Return the result as struct ng_mesg plus ASCII string */ 2788 bufSize = strlen(ascii->data) + 1; 2789 ascii->header.arglen = bufSize; 2790 resp->header.arglen = sizeof(*ascii) + bufSize; 2791 break; 2792 } 2793 2794 case NGM_ASCII2BINARY: 2795 { 2796 int bufSize = 2000; /* XXX hard coded constant */ 2797 const struct ng_cmdlist *c; 2798 const struct ng_parse_type *argstype; 2799 struct ng_mesg *ascii, *binary; 2800 int off = 0; 2801 2802 /* Data area must contain at least a struct ng_mesg + '\0' */ 2803 ascii = (struct ng_mesg *)msg->data; 2804 if ((msg->header.arglen < sizeof(*ascii) + 1) || 2805 (ascii->header.arglen < 1) || 2806 (msg->header.arglen < sizeof(*ascii) + 2807 ascii->header.arglen)) { 2808 TRAP_ERROR(); 2809 error = EINVAL; 2810 break; 2811 } 2812 ascii->data[ascii->header.arglen - 1] = '\0'; 2813 2814 /* Get a response message with lots of room */ 2815 NG_MKRESPONSE(resp, msg, sizeof(*binary) + bufSize, M_NOWAIT); 2816 if (resp == NULL) { 2817 error = ENOMEM; 2818 break; 2819 } 2820 binary = (struct ng_mesg *)resp->data; 2821 2822 /* Copy ASCII message header to response message payload */ 2823 bcopy(ascii, binary, sizeof(*ascii)); 2824 2825 /* Find command by matching ASCII command string */ 2826 for (c = here->nd_type->cmdlist; 2827 c != NULL && c->name != NULL; c++) { 2828 if (strcmp(ascii->header.cmdstr, c->name) == 0) 2829 break; 2830 } 2831 if (c == NULL || c->name == NULL) { 2832 for (c = ng_generic_cmds; c->name != NULL; c++) { 2833 if (strcmp(ascii->header.cmdstr, c->name) == 0) 2834 break; 2835 } 2836 if (c->name == NULL) { 2837 NG_FREE_MSG(resp); 2838 error = ENOSYS; 2839 break; 2840 } 2841 } 2842 2843 /* Convert command name to binary */ 2844 binary->header.cmd = c->cmd; 2845 binary->header.typecookie = c->cookie; 2846 2847 /* Convert command arguments to binary */ 2848 argstype = (binary->header.flags & NGF_RESP) ? 2849 c->respType : c->mesgType; 2850 if (argstype == NULL) { 2851 bufSize = 0; 2852 } else { 2853 if ((error = ng_parse(argstype, ascii->data, 2854 &off, (u_char *)binary->data, &bufSize)) != 0) { 2855 NG_FREE_MSG(resp); 2856 break; 2857 } 2858 } 2859 2860 /* Return the result */ 2861 binary->header.arglen = bufSize; 2862 resp->header.arglen = sizeof(*binary) + bufSize; 2863 break; 2864 } 2865 2866 case NGM_TEXT_CONFIG: 2867 case NGM_TEXT_STATUS: 2868 /* 2869 * This one is tricky as it passes the command down to the 2870 * actual node, even though it is a generic type command. 2871 * This means we must assume that the item/msg is already freed 2872 * when control passes back to us. 2873 */ 2874 if (here->nd_type->rcvmsg != NULL) { 2875 NGI_MSG(item) = msg; /* put it back as we found it */ 2876 return((*here->nd_type->rcvmsg)(here, item, lasthook)); 2877 } 2878 /* Fall through if rcvmsg not supported */ 2879 default: 2880 TRAP_ERROR(); 2881 error = EINVAL; 2882 } 2883 /* 2884 * Sometimes a generic message may be statically allocated 2885 * to avoid problems with allocating when in tight memeory situations. 2886 * Don't free it if it is so. 2887 * I break them appart here, because erros may cause a free if the item 2888 * in which case we'd be doing it twice. 2889 * they are kept together above, to simplify freeing. 2890 */ 2891 out: 2892 NG_RESPOND_MSG(error, here, item, resp); 2893 if (msg) 2894 NG_FREE_MSG(msg); 2895 return (error); 2896 } 2897 2898 /************************************************************************ 2899 Queue element get/free routines 2900 ************************************************************************/ 2901 2902 uma_zone_t ng_qzone; 2903 static int maxalloc = 512; /* limit the damage of a leak */ 2904 2905 TUNABLE_INT("net.graph.maxalloc", &maxalloc); 2906 SYSCTL_INT(_net_graph, OID_AUTO, maxalloc, CTLFLAG_RDTUN, &maxalloc, 2907 0, "Maximum number of queue items to allocate"); 2908 2909 #ifdef NETGRAPH_DEBUG 2910 static TAILQ_HEAD(, ng_item) ng_itemlist = TAILQ_HEAD_INITIALIZER(ng_itemlist); 2911 static int allocated; /* number of items malloc'd */ 2912 #endif 2913 2914 /* 2915 * Get a queue entry. 2916 * This is usually called when a packet first enters netgraph. 2917 * By definition, this is usually from an interrupt, or from a user. 2918 * Users are not so important, but try be quick for the times that it's 2919 * an interrupt. 2920 */ 2921 static __inline item_p 2922 ng_getqblk(int flags) 2923 { 2924 item_p item = NULL; 2925 int wait; 2926 2927 wait = (flags & NG_WAITOK) ? M_WAITOK : M_NOWAIT; 2928 2929 item = uma_zalloc(ng_qzone, wait | M_ZERO); 2930 2931 #ifdef NETGRAPH_DEBUG 2932 if (item) { 2933 mtx_lock(&ngq_mtx); 2934 TAILQ_INSERT_TAIL(&ng_itemlist, item, all); 2935 allocated++; 2936 mtx_unlock(&ngq_mtx); 2937 } 2938 #endif 2939 2940 return (item); 2941 } 2942 2943 /* 2944 * Release a queue entry 2945 */ 2946 void 2947 ng_free_item(item_p item) 2948 { 2949 KASSERT(item->apply == NULL, ("%s: leaking apply callback", __func__)); 2950 2951 /* 2952 * The item may hold resources on it's own. We need to free 2953 * these before we can free the item. What they are depends upon 2954 * what kind of item it is. it is important that nodes zero 2955 * out pointers to resources that they remove from the item 2956 * or we release them again here. 2957 */ 2958 switch (item->el_flags & NGQF_TYPE) { 2959 case NGQF_DATA: 2960 /* If we have an mbuf still attached.. */ 2961 NG_FREE_M(_NGI_M(item)); 2962 break; 2963 case NGQF_MESG: 2964 _NGI_RETADDR(item) = 0; 2965 NG_FREE_MSG(_NGI_MSG(item)); 2966 break; 2967 case NGQF_FN: 2968 /* nothing to free really, */ 2969 _NGI_FN(item) = NULL; 2970 _NGI_ARG1(item) = NULL; 2971 _NGI_ARG2(item) = 0; 2972 case NGQF_UNDEF: 2973 break; 2974 } 2975 /* If we still have a node or hook referenced... */ 2976 _NGI_CLR_NODE(item); 2977 _NGI_CLR_HOOK(item); 2978 2979 #ifdef NETGRAPH_DEBUG 2980 mtx_lock(&ngq_mtx); 2981 TAILQ_REMOVE(&ng_itemlist, item, all); 2982 allocated--; 2983 mtx_unlock(&ngq_mtx); 2984 #endif 2985 uma_zfree(ng_qzone, item); 2986 } 2987 2988 /************************************************************************ 2989 Module routines 2990 ************************************************************************/ 2991 2992 /* 2993 * Handle the loading/unloading of a netgraph node type module 2994 */ 2995 int 2996 ng_mod_event(module_t mod, int event, void *data) 2997 { 2998 struct ng_type *const type = data; 2999 int s, error = 0; 3000 3001 switch (event) { 3002 case MOD_LOAD: 3003 3004 /* Register new netgraph node type */ 3005 s = splnet(); 3006 if ((error = ng_newtype(type)) != 0) { 3007 splx(s); 3008 break; 3009 } 3010 3011 /* Call type specific code */ 3012 if (type->mod_event != NULL) 3013 if ((error = (*type->mod_event)(mod, event, data))) { 3014 mtx_lock(&ng_typelist_mtx); 3015 type->refs--; /* undo it */ 3016 LIST_REMOVE(type, types); 3017 mtx_unlock(&ng_typelist_mtx); 3018 } 3019 splx(s); 3020 break; 3021 3022 case MOD_UNLOAD: 3023 s = splnet(); 3024 if (type->refs > 1) { /* make sure no nodes exist! */ 3025 error = EBUSY; 3026 } else { 3027 if (type->refs == 0) { 3028 /* failed load, nothing to undo */ 3029 splx(s); 3030 break; 3031 } 3032 if (type->mod_event != NULL) { /* check with type */ 3033 error = (*type->mod_event)(mod, event, data); 3034 if (error != 0) { /* type refuses.. */ 3035 splx(s); 3036 break; 3037 } 3038 } 3039 mtx_lock(&ng_typelist_mtx); 3040 LIST_REMOVE(type, types); 3041 mtx_unlock(&ng_typelist_mtx); 3042 } 3043 splx(s); 3044 break; 3045 3046 default: 3047 if (type->mod_event != NULL) 3048 error = (*type->mod_event)(mod, event, data); 3049 else 3050 error = EOPNOTSUPP; /* XXX ? */ 3051 break; 3052 } 3053 return (error); 3054 } 3055 3056 /* 3057 * Handle loading and unloading for this code. 3058 * The only thing we need to link into is the NETISR strucure. 3059 */ 3060 static int 3061 ngb_mod_event(module_t mod, int event, void *data) 3062 { 3063 int error = 0; 3064 3065 switch (event) { 3066 case MOD_LOAD: 3067 /* Initialize everything. */ 3068 mtx_init(&ng_worklist_mtx, "ng_worklist", NULL, MTX_SPIN); 3069 mtx_init(&ng_typelist_mtx, "netgraph types mutex", NULL, 3070 MTX_DEF); 3071 mtx_init(&ng_nodelist_mtx, "netgraph nodelist mutex", NULL, 3072 MTX_DEF); 3073 mtx_init(&ng_idhash_mtx, "netgraph idhash mutex", NULL, 3074 MTX_DEF); 3075 mtx_init(&ng_topo_mtx, "netgraph topology mutex", NULL, 3076 MTX_DEF); 3077 #ifdef NETGRAPH_DEBUG 3078 mtx_init(&ngq_mtx, "netgraph item list mutex", NULL, 3079 MTX_DEF); 3080 #endif 3081 ng_qzone = uma_zcreate("NetGraph items", sizeof(struct ng_item), 3082 NULL, NULL, NULL, NULL, UMA_ALIGN_CACHE, 0); 3083 uma_zone_set_max(ng_qzone, maxalloc); 3084 netisr_register(NETISR_NETGRAPH, (netisr_t *)ngintr, NULL, 3085 NETISR_MPSAFE); 3086 break; 3087 case MOD_UNLOAD: 3088 /* You cant unload it because an interface may be using it. */ 3089 error = EBUSY; 3090 break; 3091 default: 3092 error = EOPNOTSUPP; 3093 break; 3094 } 3095 return (error); 3096 } 3097 3098 static moduledata_t netgraph_mod = { 3099 "netgraph", 3100 ngb_mod_event, 3101 (NULL) 3102 }; 3103 DECLARE_MODULE(netgraph, netgraph_mod, SI_SUB_NETGRAPH, SI_ORDER_MIDDLE); 3104 SYSCTL_NODE(_net, OID_AUTO, graph, CTLFLAG_RW, 0, "netgraph Family"); 3105 SYSCTL_INT(_net_graph, OID_AUTO, abi_version, CTLFLAG_RD, 0, NG_ABI_VERSION,""); 3106 SYSCTL_INT(_net_graph, OID_AUTO, msg_version, CTLFLAG_RD, 0, NG_VERSION, ""); 3107 3108 #ifdef NETGRAPH_DEBUG 3109 void 3110 dumphook (hook_p hook, char *file, int line) 3111 { 3112 printf("hook: name %s, %d refs, Last touched:\n", 3113 _NG_HOOK_NAME(hook), hook->hk_refs); 3114 printf(" Last active @ %s, line %d\n", 3115 hook->lastfile, hook->lastline); 3116 if (line) { 3117 printf(" problem discovered at file %s, line %d\n", file, line); 3118 } 3119 } 3120 3121 void 3122 dumpnode(node_p node, char *file, int line) 3123 { 3124 printf("node: ID [%x]: type '%s', %d hooks, flags 0x%x, %d refs, %s:\n", 3125 _NG_NODE_ID(node), node->nd_type->name, 3126 node->nd_numhooks, node->nd_flags, 3127 node->nd_refs, node->nd_name); 3128 printf(" Last active @ %s, line %d\n", 3129 node->lastfile, node->lastline); 3130 if (line) { 3131 printf(" problem discovered at file %s, line %d\n", file, line); 3132 } 3133 } 3134 3135 void 3136 dumpitem(item_p item, char *file, int line) 3137 { 3138 printf(" ACTIVE item, last used at %s, line %d", 3139 item->lastfile, item->lastline); 3140 switch(item->el_flags & NGQF_TYPE) { 3141 case NGQF_DATA: 3142 printf(" - [data]\n"); 3143 break; 3144 case NGQF_MESG: 3145 printf(" - retaddr[%d]:\n", _NGI_RETADDR(item)); 3146 break; 3147 case NGQF_FN: 3148 printf(" - fn@%p (%p, %p, %p, %d (%x))\n", 3149 item->body.fn.fn_fn, 3150 _NGI_NODE(item), 3151 _NGI_HOOK(item), 3152 item->body.fn.fn_arg1, 3153 item->body.fn.fn_arg2, 3154 item->body.fn.fn_arg2); 3155 break; 3156 case NGQF_UNDEF: 3157 printf(" - UNDEFINED!\n"); 3158 } 3159 if (line) { 3160 printf(" problem discovered at file %s, line %d\n", file, line); 3161 if (_NGI_NODE(item)) { 3162 printf("node %p ([%x])\n", 3163 _NGI_NODE(item), ng_node2ID(_NGI_NODE(item))); 3164 } 3165 } 3166 } 3167 3168 static void 3169 ng_dumpitems(void) 3170 { 3171 item_p item; 3172 int i = 1; 3173 TAILQ_FOREACH(item, &ng_itemlist, all) { 3174 printf("[%d] ", i++); 3175 dumpitem(item, NULL, 0); 3176 } 3177 } 3178 3179 static void 3180 ng_dumpnodes(void) 3181 { 3182 node_p node; 3183 int i = 1; 3184 mtx_lock(&ng_nodelist_mtx); 3185 SLIST_FOREACH(node, &ng_allnodes, nd_all) { 3186 printf("[%d] ", i++); 3187 dumpnode(node, NULL, 0); 3188 } 3189 mtx_unlock(&ng_nodelist_mtx); 3190 } 3191 3192 static void 3193 ng_dumphooks(void) 3194 { 3195 hook_p hook; 3196 int i = 1; 3197 mtx_lock(&ng_nodelist_mtx); 3198 SLIST_FOREACH(hook, &ng_allhooks, hk_all) { 3199 printf("[%d] ", i++); 3200 dumphook(hook, NULL, 0); 3201 } 3202 mtx_unlock(&ng_nodelist_mtx); 3203 } 3204 3205 static int 3206 sysctl_debug_ng_dump_items(SYSCTL_HANDLER_ARGS) 3207 { 3208 int error; 3209 int val; 3210 int i; 3211 3212 val = allocated; 3213 i = 1; 3214 error = sysctl_handle_int(oidp, &val, sizeof(int), req); 3215 if (error != 0 || req->newptr == NULL) 3216 return (error); 3217 if (val == 42) { 3218 ng_dumpitems(); 3219 ng_dumpnodes(); 3220 ng_dumphooks(); 3221 } 3222 return (0); 3223 } 3224 3225 SYSCTL_PROC(_debug, OID_AUTO, ng_dump_items, CTLTYPE_INT | CTLFLAG_RW, 3226 0, sizeof(int), sysctl_debug_ng_dump_items, "I", "Number of allocated items"); 3227 #endif /* NETGRAPH_DEBUG */ 3228 3229 3230 /*********************************************************************** 3231 * Worklist routines 3232 **********************************************************************/ 3233 /* NETISR thread enters here */ 3234 /* 3235 * Pick a node off the list of nodes with work, 3236 * try get an item to process off it. 3237 * If there are no more, remove the node from the list. 3238 */ 3239 static void 3240 ngintr(void) 3241 { 3242 item_p item; 3243 node_p node = NULL; 3244 3245 for (;;) { 3246 mtx_lock_spin(&ng_worklist_mtx); 3247 node = TAILQ_FIRST(&ng_worklist); 3248 if (!node) { 3249 mtx_unlock_spin(&ng_worklist_mtx); 3250 break; 3251 } 3252 node->nd_flags &= ~NGF_WORKQ; 3253 TAILQ_REMOVE(&ng_worklist, node, nd_work); 3254 mtx_unlock_spin(&ng_worklist_mtx); 3255 CTR3(KTR_NET, "%20s: node [%x] (%p) taken off worklist", 3256 __func__, node->nd_ID, node); 3257 /* 3258 * We have the node. We also take over the reference 3259 * that the list had on it. 3260 * Now process as much as you can, until it won't 3261 * let you have another item off the queue. 3262 * All this time, keep the reference 3263 * that lets us be sure that the node still exists. 3264 * Let the reference go at the last minute. 3265 * ng_dequeue will put us back on the worklist 3266 * if there is more too do. This may be of use if there 3267 * are Multiple Processors and multiple Net threads in the 3268 * future. 3269 */ 3270 for (;;) { 3271 int rw; 3272 3273 mtx_lock_spin(&node->nd_input_queue.q_mtx); 3274 item = ng_dequeue(&node->nd_input_queue, &rw); 3275 if (item == NULL) { 3276 mtx_unlock_spin(&node->nd_input_queue.q_mtx); 3277 break; /* go look for another node */ 3278 } else { 3279 mtx_unlock_spin(&node->nd_input_queue.q_mtx); 3280 NGI_GET_NODE(item, node); /* zaps stored node */ 3281 ng_apply_item(node, item, rw); 3282 NG_NODE_UNREF(node); 3283 } 3284 } 3285 NG_NODE_UNREF(node); 3286 } 3287 } 3288 3289 static void 3290 ng_worklist_remove(node_p node) 3291 { 3292 mtx_assert(&node->nd_input_queue.q_mtx, MA_OWNED); 3293 3294 mtx_lock_spin(&ng_worklist_mtx); 3295 if (node->nd_flags & NGF_WORKQ) { 3296 node->nd_flags &= ~NGF_WORKQ; 3297 TAILQ_REMOVE(&ng_worklist, node, nd_work); 3298 mtx_unlock_spin(&ng_worklist_mtx); 3299 NG_NODE_UNREF(node); 3300 CTR3(KTR_NET, "%20s: node [%x] (%p) removed from worklist", 3301 __func__, node->nd_ID, node); 3302 } else { 3303 mtx_unlock_spin(&ng_worklist_mtx); 3304 } 3305 } 3306 3307 /* 3308 * XXX 3309 * It's posible that a debugging NG_NODE_REF may need 3310 * to be outside the mutex zone 3311 */ 3312 static void 3313 ng_setisr(node_p node) 3314 { 3315 3316 mtx_assert(&node->nd_input_queue.q_mtx, MA_OWNED); 3317 3318 if ((node->nd_flags & NGF_WORKQ) == 0) { 3319 /* 3320 * If we are not already on the work queue, 3321 * then put us on. 3322 */ 3323 node->nd_flags |= NGF_WORKQ; 3324 mtx_lock_spin(&ng_worklist_mtx); 3325 TAILQ_INSERT_TAIL(&ng_worklist, node, nd_work); 3326 mtx_unlock_spin(&ng_worklist_mtx); 3327 NG_NODE_REF(node); /* XXX fafe in mutex? */ 3328 CTR3(KTR_NET, "%20s: node [%x] (%p) put on worklist", __func__, 3329 node->nd_ID, node); 3330 } else 3331 CTR3(KTR_NET, "%20s: node [%x] (%p) already on worklist", 3332 __func__, node->nd_ID, node); 3333 schednetisr(NETISR_NETGRAPH); 3334 } 3335 3336 3337 /*********************************************************************** 3338 * Externally useable functions to set up a queue item ready for sending 3339 ***********************************************************************/ 3340 3341 #ifdef NETGRAPH_DEBUG 3342 #define ITEM_DEBUG_CHECKS \ 3343 do { \ 3344 if (NGI_NODE(item) ) { \ 3345 printf("item already has node"); \ 3346 kdb_enter("has node"); \ 3347 NGI_CLR_NODE(item); \ 3348 } \ 3349 if (NGI_HOOK(item) ) { \ 3350 printf("item already has hook"); \ 3351 kdb_enter("has hook"); \ 3352 NGI_CLR_HOOK(item); \ 3353 } \ 3354 } while (0) 3355 #else 3356 #define ITEM_DEBUG_CHECKS 3357 #endif 3358 3359 /* 3360 * Put mbuf into the item. 3361 * Hook and node references will be removed when the item is dequeued. 3362 * (or equivalent) 3363 * (XXX) Unsafe because no reference held by peer on remote node. 3364 * remote node might go away in this timescale. 3365 * We know the hooks can't go away because that would require getting 3366 * a writer item on both nodes and we must have at least a reader 3367 * here to be able to do this. 3368 * Note that the hook loaded is the REMOTE hook. 3369 * 3370 * This is possibly in the critical path for new data. 3371 */ 3372 item_p 3373 ng_package_data(struct mbuf *m, int flags) 3374 { 3375 item_p item; 3376 3377 if ((item = ng_getqblk(flags)) == NULL) { 3378 NG_FREE_M(m); 3379 return (NULL); 3380 } 3381 ITEM_DEBUG_CHECKS; 3382 item->el_flags = NGQF_DATA | NGQF_READER; 3383 item->el_next = NULL; 3384 NGI_M(item) = m; 3385 return (item); 3386 } 3387 3388 /* 3389 * Allocate a queue item and put items into it.. 3390 * Evaluate the address as this will be needed to queue it and 3391 * to work out what some of the fields should be. 3392 * Hook and node references will be removed when the item is dequeued. 3393 * (or equivalent) 3394 */ 3395 item_p 3396 ng_package_msg(struct ng_mesg *msg, int flags) 3397 { 3398 item_p item; 3399 3400 if ((item = ng_getqblk(flags)) == NULL) { 3401 NG_FREE_MSG(msg); 3402 return (NULL); 3403 } 3404 ITEM_DEBUG_CHECKS; 3405 /* Messages items count as writers unless explicitly exempted. */ 3406 if (msg->header.cmd & NGM_READONLY) 3407 item->el_flags = NGQF_MESG | NGQF_READER; 3408 else 3409 item->el_flags = NGQF_MESG | NGQF_WRITER; 3410 item->el_next = NULL; 3411 /* 3412 * Set the current lasthook into the queue item 3413 */ 3414 NGI_MSG(item) = msg; 3415 NGI_RETADDR(item) = 0; 3416 return (item); 3417 } 3418 3419 3420 3421 #define SET_RETADDR(item, here, retaddr) \ 3422 do { /* Data or fn items don't have retaddrs */ \ 3423 if ((item->el_flags & NGQF_TYPE) == NGQF_MESG) { \ 3424 if (retaddr) { \ 3425 NGI_RETADDR(item) = retaddr; \ 3426 } else { \ 3427 /* \ 3428 * The old return address should be ok. \ 3429 * If there isn't one, use the address \ 3430 * here. \ 3431 */ \ 3432 if (NGI_RETADDR(item) == 0) { \ 3433 NGI_RETADDR(item) \ 3434 = ng_node2ID(here); \ 3435 } \ 3436 } \ 3437 } \ 3438 } while (0) 3439 3440 int 3441 ng_address_hook(node_p here, item_p item, hook_p hook, ng_ID_t retaddr) 3442 { 3443 hook_p peer; 3444 node_p peernode; 3445 ITEM_DEBUG_CHECKS; 3446 /* 3447 * Quick sanity check.. 3448 * Since a hook holds a reference on it's node, once we know 3449 * that the peer is still connected (even if invalid,) we know 3450 * that the peer node is present, though maybe invalid. 3451 */ 3452 if ((hook == NULL) 3453 || NG_HOOK_NOT_VALID(hook) 3454 || (NG_HOOK_PEER(hook) == NULL) 3455 || NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook)) 3456 || NG_NODE_NOT_VALID(NG_PEER_NODE(hook))) { 3457 NG_FREE_ITEM(item); 3458 TRAP_ERROR(); 3459 return (ENETDOWN); 3460 } 3461 3462 /* 3463 * Transfer our interest to the other (peer) end. 3464 */ 3465 peer = NG_HOOK_PEER(hook); 3466 NG_HOOK_REF(peer); 3467 NGI_SET_HOOK(item, peer); 3468 peernode = NG_PEER_NODE(hook); 3469 NG_NODE_REF(peernode); 3470 NGI_SET_NODE(item, peernode); 3471 SET_RETADDR(item, here, retaddr); 3472 return (0); 3473 } 3474 3475 int 3476 ng_address_path(node_p here, item_p item, char *address, ng_ID_t retaddr) 3477 { 3478 node_p dest = NULL; 3479 hook_p hook = NULL; 3480 int error; 3481 3482 ITEM_DEBUG_CHECKS; 3483 /* 3484 * Note that ng_path2noderef increments the reference count 3485 * on the node for us if it finds one. So we don't have to. 3486 */ 3487 error = ng_path2noderef(here, address, &dest, &hook); 3488 if (error) { 3489 NG_FREE_ITEM(item); 3490 return (error); 3491 } 3492 NGI_SET_NODE(item, dest); 3493 if ( hook) { 3494 NG_HOOK_REF(hook); /* don't let it go while on the queue */ 3495 NGI_SET_HOOK(item, hook); 3496 } 3497 SET_RETADDR(item, here, retaddr); 3498 return (0); 3499 } 3500 3501 int 3502 ng_address_ID(node_p here, item_p item, ng_ID_t ID, ng_ID_t retaddr) 3503 { 3504 node_p dest; 3505 3506 ITEM_DEBUG_CHECKS; 3507 /* 3508 * Find the target node. 3509 */ 3510 dest = ng_ID2noderef(ID); /* GETS REFERENCE! */ 3511 if (dest == NULL) { 3512 NG_FREE_ITEM(item); 3513 TRAP_ERROR(); 3514 return(EINVAL); 3515 } 3516 /* Fill out the contents */ 3517 NGI_SET_NODE(item, dest); 3518 NGI_CLR_HOOK(item); 3519 SET_RETADDR(item, here, retaddr); 3520 return (0); 3521 } 3522 3523 /* 3524 * special case to send a message to self (e.g. destroy node) 3525 * Possibly indicate an arrival hook too. 3526 * Useful for removing that hook :-) 3527 */ 3528 item_p 3529 ng_package_msg_self(node_p here, hook_p hook, struct ng_mesg *msg) 3530 { 3531 item_p item; 3532 3533 /* 3534 * Find the target node. 3535 * If there is a HOOK argument, then use that in preference 3536 * to the address. 3537 */ 3538 if ((item = ng_getqblk(NG_NOFLAGS)) == NULL) { 3539 NG_FREE_MSG(msg); 3540 return (NULL); 3541 } 3542 3543 /* Fill out the contents */ 3544 item->el_flags = NGQF_MESG | NGQF_WRITER; 3545 item->el_next = NULL; 3546 NG_NODE_REF(here); 3547 NGI_SET_NODE(item, here); 3548 if (hook) { 3549 NG_HOOK_REF(hook); 3550 NGI_SET_HOOK(item, hook); 3551 } 3552 NGI_MSG(item) = msg; 3553 NGI_RETADDR(item) = ng_node2ID(here); 3554 return (item); 3555 } 3556 3557 int 3558 ng_send_fn1(node_p node, hook_p hook, ng_item_fn *fn, void * arg1, int arg2, 3559 int flags) 3560 { 3561 item_p item; 3562 3563 if ((item = ng_getqblk(flags)) == NULL) { 3564 return (ENOMEM); 3565 } 3566 item->el_flags = NGQF_FN | NGQF_WRITER; 3567 NG_NODE_REF(node); /* and one for the item */ 3568 NGI_SET_NODE(item, node); 3569 if (hook) { 3570 NG_HOOK_REF(hook); 3571 NGI_SET_HOOK(item, hook); 3572 } 3573 NGI_FN(item) = fn; 3574 NGI_ARG1(item) = arg1; 3575 NGI_ARG2(item) = arg2; 3576 return(ng_snd_item(item, flags)); 3577 } 3578 3579 /* 3580 * Official timeout routines for Netgraph nodes. 3581 */ 3582 static void 3583 ng_callout_trampoline(void *arg) 3584 { 3585 item_p item = arg; 3586 3587 ng_snd_item(item, 0); 3588 } 3589 3590 3591 int 3592 ng_callout(struct callout *c, node_p node, hook_p hook, int ticks, 3593 ng_item_fn *fn, void * arg1, int arg2) 3594 { 3595 item_p item, oitem; 3596 3597 if ((item = ng_getqblk(NG_NOFLAGS)) == NULL) 3598 return (ENOMEM); 3599 3600 item->el_flags = NGQF_FN | NGQF_WRITER; 3601 NG_NODE_REF(node); /* and one for the item */ 3602 NGI_SET_NODE(item, node); 3603 if (hook) { 3604 NG_HOOK_REF(hook); 3605 NGI_SET_HOOK(item, hook); 3606 } 3607 NGI_FN(item) = fn; 3608 NGI_ARG1(item) = arg1; 3609 NGI_ARG2(item) = arg2; 3610 oitem = c->c_arg; 3611 if (callout_reset(c, ticks, &ng_callout_trampoline, item) == 1 && 3612 oitem != NULL) 3613 NG_FREE_ITEM(oitem); 3614 return (0); 3615 } 3616 3617 /* A special modified version of untimeout() */ 3618 int 3619 ng_uncallout(struct callout *c, node_p node) 3620 { 3621 item_p item; 3622 int rval; 3623 3624 KASSERT(c != NULL, ("ng_uncallout: NULL callout")); 3625 KASSERT(node != NULL, ("ng_uncallout: NULL node")); 3626 3627 rval = callout_stop(c); 3628 item = c->c_arg; 3629 /* Do an extra check */ 3630 if ((rval > 0) && (c->c_func == &ng_callout_trampoline) && 3631 (NGI_NODE(item) == node)) { 3632 /* 3633 * We successfully removed it from the queue before it ran 3634 * So now we need to unreference everything that was 3635 * given extra references. (NG_FREE_ITEM does this). 3636 */ 3637 NG_FREE_ITEM(item); 3638 } 3639 c->c_arg = NULL; 3640 3641 return (rval); 3642 } 3643 3644 /* 3645 * Set the address, if none given, give the node here. 3646 */ 3647 void 3648 ng_replace_retaddr(node_p here, item_p item, ng_ID_t retaddr) 3649 { 3650 if (retaddr) { 3651 NGI_RETADDR(item) = retaddr; 3652 } else { 3653 /* 3654 * The old return address should be ok. 3655 * If there isn't one, use the address here. 3656 */ 3657 NGI_RETADDR(item) = ng_node2ID(here); 3658 } 3659 } 3660 3661 #define TESTING 3662 #ifdef TESTING 3663 /* just test all the macros */ 3664 void 3665 ng_macro_test(item_p item); 3666 void 3667 ng_macro_test(item_p item) 3668 { 3669 node_p node = NULL; 3670 hook_p hook = NULL; 3671 struct mbuf *m; 3672 struct ng_mesg *msg; 3673 ng_ID_t retaddr; 3674 int error; 3675 3676 NGI_GET_M(item, m); 3677 NGI_GET_MSG(item, msg); 3678 retaddr = NGI_RETADDR(item); 3679 NG_SEND_DATA(error, hook, m, NULL); 3680 NG_SEND_DATA_ONLY(error, hook, m); 3681 NG_FWD_NEW_DATA(error, item, hook, m); 3682 NG_FWD_ITEM_HOOK(error, item, hook); 3683 NG_SEND_MSG_HOOK(error, node, msg, hook, retaddr); 3684 NG_SEND_MSG_ID(error, node, msg, retaddr, retaddr); 3685 NG_SEND_MSG_PATH(error, node, msg, ".:", retaddr); 3686 NG_FWD_MSG_HOOK(error, node, item, hook, retaddr); 3687 } 3688 #endif /* TESTING */ 3689 3690