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: releng/6.0/sys/netgraph/ng_base.c 150045 2005-09-12 14:46:19Z glebius $
42 * $Whistle: ng_base.c,v 1.39 1999/01/28 23:54:53 julian Exp $
43 */
44
45 /*
46 * This file implements the base netgraph code.
47 */
48
49 #include <sys/param.h>
50 #include <sys/systm.h>
51 #include <sys/ctype.h>
52 #include <sys/errno.h>
53 #include <sys/kdb.h>
54 #include <sys/kernel.h>
55 #include <sys/limits.h>
56 #include <sys/malloc.h>
57 #include <sys/mbuf.h>
58 #include <sys/queue.h>
59 #include <sys/sysctl.h>
60 #include <sys/syslog.h>
61
62 #include <net/netisr.h>
63
64 #include <netgraph/ng_message.h>
65 #include <netgraph/netgraph.h>
66 #include <netgraph/ng_parse.h>
67
68 MODULE_VERSION(netgraph, NG_ABI_VERSION);
69
70 /* List of all active nodes */
71 static LIST_HEAD(, ng_node) ng_nodelist;
72 static struct mtx ng_nodelist_mtx;
73
74 #ifdef NETGRAPH_DEBUG
75 static struct mtx ngq_mtx; /* protects the queue item list */
76
77 static SLIST_HEAD(, ng_node) ng_allnodes;
78 static LIST_HEAD(, ng_node) ng_freenodes; /* in debug, we never free() them */
79 static SLIST_HEAD(, ng_hook) ng_allhooks;
80 static LIST_HEAD(, ng_hook) ng_freehooks; /* in debug, we never free() them */
81
82 static void ng_dumpitems(void);
83 static void ng_dumpnodes(void);
84 static void ng_dumphooks(void);
85
86 #endif /* NETGRAPH_DEBUG */
87 /*
88 * DEAD versions of the structures.
89 * In order to avoid races, it is sometimes neccesary to point
90 * at SOMETHING even though theoretically, the current entity is
91 * INVALID. Use these to avoid these races.
92 */
93 struct ng_type ng_deadtype = {
94 NG_ABI_VERSION,
95 "dead",
96 NULL, /* modevent */
97 NULL, /* constructor */
98 NULL, /* rcvmsg */
99 NULL, /* shutdown */
100 NULL, /* newhook */
101 NULL, /* findhook */
102 NULL, /* connect */
103 NULL, /* rcvdata */
104 NULL, /* disconnect */
105 NULL, /* cmdlist */
106 };
107
108 struct ng_node ng_deadnode = {
109 "dead",
110 &ng_deadtype,
111 NGF_INVALID,
112 1, /* refs */
113 0, /* numhooks */
114 NULL, /* private */
115 0, /* ID */
116 LIST_HEAD_INITIALIZER(ng_deadnode.hooks),
117 {}, /* all_nodes list entry */
118 {}, /* id hashtable list entry */
119 {}, /* workqueue entry */
120 { 0,
121 {}, /* should never use! (should hang) */
122 NULL,
123 &ng_deadnode.nd_input_queue.queue,
124 &ng_deadnode
125 },
126 #ifdef NETGRAPH_DEBUG
127 ND_MAGIC,
128 __FILE__,
129 __LINE__,
130 {NULL}
131 #endif /* NETGRAPH_DEBUG */
132 };
133
134 struct ng_hook ng_deadhook = {
135 "dead",
136 NULL, /* private */
137 HK_INVALID | HK_DEAD,
138 1, /* refs always >= 1 */
139 0, /* undefined data link type */
140 &ng_deadhook, /* Peer is self */
141 &ng_deadnode, /* attached to deadnode */
142 {}, /* hooks list */
143 NULL, /* override rcvmsg() */
144 NULL, /* override rcvdata() */
145 #ifdef NETGRAPH_DEBUG
146 HK_MAGIC,
147 __FILE__,
148 __LINE__,
149 {NULL}
150 #endif /* NETGRAPH_DEBUG */
151 };
152
153 /*
154 * END DEAD STRUCTURES
155 */
156 /* List nodes with unallocated work */
157 static TAILQ_HEAD(, ng_node) ng_worklist = TAILQ_HEAD_INITIALIZER(ng_worklist);
158 static struct mtx ng_worklist_mtx; /* MUST LOCK NODE FIRST */
159
160 /* List of installed types */
161 static LIST_HEAD(, ng_type) ng_typelist;
162 static struct mtx ng_typelist_mtx;
163
164 /* Hash related definitions */
165 /* XXX Don't need to initialise them because it's a LIST */
166 #define NG_ID_HASH_SIZE 32 /* most systems wont need even this many */
167 static LIST_HEAD(, ng_node) ng_ID_hash[NG_ID_HASH_SIZE];
168 static struct mtx ng_idhash_mtx;
169 /* Method to find a node.. used twice so do it here */
170 #define NG_IDHASH_FN(ID) ((ID) % (NG_ID_HASH_SIZE))
171 #define NG_IDHASH_FIND(ID, node) \
172 do { \
173 mtx_assert(&ng_idhash_mtx, MA_OWNED); \
174 LIST_FOREACH(node, &ng_ID_hash[NG_IDHASH_FN(ID)], \
175 nd_idnodes) { \
176 if (NG_NODE_IS_VALID(node) \
177 && (NG_NODE_ID(node) == ID)) { \
178 break; \
179 } \
180 } \
181 } while (0)
182
183
184 /* Internal functions */
185 static int ng_add_hook(node_p node, const char *name, hook_p * hookp);
186 static int ng_generic_msg(node_p here, item_p item, hook_p lasthook);
187 static ng_ID_t ng_decodeidname(const char *name);
188 static int ngb_mod_event(module_t mod, int event, void *data);
189 static void ng_worklist_remove(node_p node);
190 static void ngintr(void);
191 static int ng_apply_item(node_p node, item_p item);
192 static void ng_flush_input_queue(struct ng_queue * ngq);
193 static void ng_setisr(node_p node);
194 static node_p ng_ID2noderef(ng_ID_t ID);
195 static int ng_con_nodes(node_p node, const char *name, node_p node2,
196 const char *name2);
197 static void ng_con_part2(node_p node, hook_p hook, void *arg1, int arg2);
198 static void ng_con_part3(node_p node, hook_p hook, void *arg1, int arg2);
199 static int ng_mkpeer(node_p node, const char *name,
200 const char *name2, char *type);
201
202 /* imported , these used to be externally visible, some may go back */
203 void ng_destroy_hook(hook_p hook);
204 node_p ng_name2noderef(node_p node, const char *name);
205 int ng_path2noderef(node_p here, const char *path,
206 node_p *dest, hook_p *lasthook);
207 int ng_make_node(const char *type, node_p *nodepp);
208 int ng_path_parse(char *addr, char **node, char **path, char **hook);
209 void ng_rmnode(node_p node, hook_p dummy1, void *dummy2, int dummy3);
210 void ng_unname(node_p node);
211
212
213 /* Our own netgraph malloc type */
214 MALLOC_DEFINE(M_NETGRAPH, "netgraph", "netgraph structures and ctrl messages");
215 MALLOC_DEFINE(M_NETGRAPH_HOOK, "netgraph_hook", "netgraph hook structures");
216 MALLOC_DEFINE(M_NETGRAPH_NODE, "netgraph_node", "netgraph node structures");
217 MALLOC_DEFINE(M_NETGRAPH_ITEM, "netgraph_item", "netgraph item structures");
218 MALLOC_DEFINE(M_NETGRAPH_MSG, "netgraph_msg", "netgraph name storage");
219
220 /* Should not be visible outside this file */
221
222 #define _NG_ALLOC_HOOK(hook) \
223 MALLOC(hook, hook_p, sizeof(*hook), M_NETGRAPH_HOOK, M_NOWAIT | M_ZERO)
224 #define _NG_ALLOC_NODE(node) \
225 MALLOC(node, node_p, sizeof(*node), M_NETGRAPH_NODE, M_NOWAIT | M_ZERO)
226
227 #ifdef NETGRAPH_DEBUG /*----------------------------------------------*/
228 /*
229 * In debug mode:
230 * In an attempt to help track reference count screwups
231 * we do not free objects back to the malloc system, but keep them
232 * in a local cache where we can examine them and keep information safely
233 * after they have been freed.
234 * We use this scheme for nodes and hooks, and to some extent for items.
235 */
236 static __inline hook_p
237 ng_alloc_hook(void)
238 {
239 hook_p hook;
240 SLIST_ENTRY(ng_hook) temp;
241 mtx_lock(&ng_nodelist_mtx);
242 hook = LIST_FIRST(&ng_freehooks);
243 if (hook) {
244 LIST_REMOVE(hook, hk_hooks);
245 bcopy(&hook->hk_all, &temp, sizeof(temp));
246 bzero(hook, sizeof(struct ng_hook));
247 bcopy(&temp, &hook->hk_all, sizeof(temp));
248 mtx_unlock(&ng_nodelist_mtx);
249 hook->hk_magic = HK_MAGIC;
250 } else {
251 mtx_unlock(&ng_nodelist_mtx);
252 _NG_ALLOC_HOOK(hook);
253 if (hook) {
254 hook->hk_magic = HK_MAGIC;
255 mtx_lock(&ng_nodelist_mtx);
256 SLIST_INSERT_HEAD(&ng_allhooks, hook, hk_all);
257 mtx_unlock(&ng_nodelist_mtx);
258 }
259 }
260 return (hook);
261 }
262
263 static __inline node_p
264 ng_alloc_node(void)
265 {
266 node_p node;
267 SLIST_ENTRY(ng_node) temp;
268 mtx_lock(&ng_nodelist_mtx);
269 node = LIST_FIRST(&ng_freenodes);
270 if (node) {
271 LIST_REMOVE(node, nd_nodes);
272 bcopy(&node->nd_all, &temp, sizeof(temp));
273 bzero(node, sizeof(struct ng_node));
274 bcopy(&temp, &node->nd_all, sizeof(temp));
275 mtx_unlock(&ng_nodelist_mtx);
276 node->nd_magic = ND_MAGIC;
277 } else {
278 mtx_unlock(&ng_nodelist_mtx);
279 _NG_ALLOC_NODE(node);
280 if (node) {
281 node->nd_magic = ND_MAGIC;
282 mtx_lock(&ng_nodelist_mtx);
283 SLIST_INSERT_HEAD(&ng_allnodes, node, nd_all);
284 mtx_unlock(&ng_nodelist_mtx);
285 }
286 }
287 return (node);
288 }
289
290 #define NG_ALLOC_HOOK(hook) do { (hook) = ng_alloc_hook(); } while (0)
291 #define NG_ALLOC_NODE(node) do { (node) = ng_alloc_node(); } while (0)
292
293
294 #define NG_FREE_HOOK(hook) \
295 do { \
296 mtx_lock(&ng_nodelist_mtx); \
297 LIST_INSERT_HEAD(&ng_freehooks, hook, hk_hooks); \
298 hook->hk_magic = 0; \
299 mtx_unlock(&ng_nodelist_mtx); \
300 } while (0)
301
302 #define NG_FREE_NODE(node) \
303 do { \
304 mtx_lock(&ng_nodelist_mtx); \
305 LIST_INSERT_HEAD(&ng_freenodes, node, nd_nodes); \
306 node->nd_magic = 0; \
307 mtx_unlock(&ng_nodelist_mtx); \
308 } while (0)
309
310 #else /* NETGRAPH_DEBUG */ /*----------------------------------------------*/
311
312 #define NG_ALLOC_HOOK(hook) _NG_ALLOC_HOOK(hook)
313 #define NG_ALLOC_NODE(node) _NG_ALLOC_NODE(node)
314
315 #define NG_FREE_HOOK(hook) do { FREE((hook), M_NETGRAPH_HOOK); } while (0)
316 #define NG_FREE_NODE(node) do { FREE((node), M_NETGRAPH_NODE); } while (0)
317
318 #endif /* NETGRAPH_DEBUG */ /*----------------------------------------------*/
319
320 /* Set this to kdb_enter("X") to catch all errors as they occur */
321 #ifndef TRAP_ERROR
322 #define TRAP_ERROR()
323 #endif
324
325 static ng_ID_t nextID = 1;
326
327 #ifdef INVARIANTS
328 #define CHECK_DATA_MBUF(m) do { \
329 struct mbuf *n; \
330 int total; \
331 \
332 M_ASSERTPKTHDR(m); \
333 for (total = 0, n = (m); n != NULL; n = n->m_next) { \
334 total += n->m_len; \
335 if (n->m_nextpkt != NULL) \
336 panic("%s: m_nextpkt", __func__); \
337 } \
338 \
339 if ((m)->m_pkthdr.len != total) { \
340 panic("%s: %d != %d", \
341 __func__, (m)->m_pkthdr.len, total); \
342 } \
343 } while (0)
344 #else
345 #define CHECK_DATA_MBUF(m)
346 #endif
347
348
349 /************************************************************************
350 Parse type definitions for generic messages
351 ************************************************************************/
352
353 /* Handy structure parse type defining macro */
354 #define DEFINE_PARSE_STRUCT_TYPE(lo, up, args) \
355 static const struct ng_parse_struct_field \
356 ng_ ## lo ## _type_fields[] = NG_GENERIC_ ## up ## _INFO args; \
357 static const struct ng_parse_type ng_generic_ ## lo ## _type = { \
358 &ng_parse_struct_type, \
359 &ng_ ## lo ## _type_fields \
360 }
361
362 DEFINE_PARSE_STRUCT_TYPE(mkpeer, MKPEER, ());
363 DEFINE_PARSE_STRUCT_TYPE(connect, CONNECT, ());
364 DEFINE_PARSE_STRUCT_TYPE(name, NAME, ());
365 DEFINE_PARSE_STRUCT_TYPE(rmhook, RMHOOK, ());
366 DEFINE_PARSE_STRUCT_TYPE(nodeinfo, NODEINFO, ());
367 DEFINE_PARSE_STRUCT_TYPE(typeinfo, TYPEINFO, ());
368 DEFINE_PARSE_STRUCT_TYPE(linkinfo, LINKINFO, (&ng_generic_nodeinfo_type));
369
370 /* Get length of an array when the length is stored as a 32 bit
371 value immediately preceding the array -- as with struct namelist
372 and struct typelist. */
373 static int
374 ng_generic_list_getLength(const struct ng_parse_type *type,
375 const u_char *start, const u_char *buf)
376 {
377 return *((const u_int32_t *)(buf - 4));
378 }
379
380 /* Get length of the array of struct linkinfo inside a struct hooklist */
381 static int
382 ng_generic_linkinfo_getLength(const struct ng_parse_type *type,
383 const u_char *start, const u_char *buf)
384 {
385 const struct hooklist *hl = (const struct hooklist *)start;
386
387 return hl->nodeinfo.hooks;
388 }
389
390 /* Array type for a variable length array of struct namelist */
391 static const struct ng_parse_array_info ng_nodeinfoarray_type_info = {
392 &ng_generic_nodeinfo_type,
393 &ng_generic_list_getLength
394 };
395 static const struct ng_parse_type ng_generic_nodeinfoarray_type = {
396 &ng_parse_array_type,
397 &ng_nodeinfoarray_type_info
398 };
399
400 /* Array type for a variable length array of struct typelist */
401 static const struct ng_parse_array_info ng_typeinfoarray_type_info = {
402 &ng_generic_typeinfo_type,
403 &ng_generic_list_getLength
404 };
405 static const struct ng_parse_type ng_generic_typeinfoarray_type = {
406 &ng_parse_array_type,
407 &ng_typeinfoarray_type_info
408 };
409
410 /* Array type for array of struct linkinfo in struct hooklist */
411 static const struct ng_parse_array_info ng_generic_linkinfo_array_type_info = {
412 &ng_generic_linkinfo_type,
413 &ng_generic_linkinfo_getLength
414 };
415 static const struct ng_parse_type ng_generic_linkinfo_array_type = {
416 &ng_parse_array_type,
417 &ng_generic_linkinfo_array_type_info
418 };
419
420 DEFINE_PARSE_STRUCT_TYPE(typelist, TYPELIST, (&ng_generic_nodeinfoarray_type));
421 DEFINE_PARSE_STRUCT_TYPE(hooklist, HOOKLIST,
422 (&ng_generic_nodeinfo_type, &ng_generic_linkinfo_array_type));
423 DEFINE_PARSE_STRUCT_TYPE(listnodes, LISTNODES,
424 (&ng_generic_nodeinfoarray_type));
425
426 /* List of commands and how to convert arguments to/from ASCII */
427 static const struct ng_cmdlist ng_generic_cmds[] = {
428 {
429 NGM_GENERIC_COOKIE,
430 NGM_SHUTDOWN,
431 "shutdown",
432 NULL,
433 NULL
434 },
435 {
436 NGM_GENERIC_COOKIE,
437 NGM_MKPEER,
438 "mkpeer",
439 &ng_generic_mkpeer_type,
440 NULL
441 },
442 {
443 NGM_GENERIC_COOKIE,
444 NGM_CONNECT,
445 "connect",
446 &ng_generic_connect_type,
447 NULL
448 },
449 {
450 NGM_GENERIC_COOKIE,
451 NGM_NAME,
452 "name",
453 &ng_generic_name_type,
454 NULL
455 },
456 {
457 NGM_GENERIC_COOKIE,
458 NGM_RMHOOK,
459 "rmhook",
460 &ng_generic_rmhook_type,
461 NULL
462 },
463 {
464 NGM_GENERIC_COOKIE,
465 NGM_NODEINFO,
466 "nodeinfo",
467 NULL,
468 &ng_generic_nodeinfo_type
469 },
470 {
471 NGM_GENERIC_COOKIE,
472 NGM_LISTHOOKS,
473 "listhooks",
474 NULL,
475 &ng_generic_hooklist_type
476 },
477 {
478 NGM_GENERIC_COOKIE,
479 NGM_LISTNAMES,
480 "listnames",
481 NULL,
482 &ng_generic_listnodes_type /* same as NGM_LISTNODES */
483 },
484 {
485 NGM_GENERIC_COOKIE,
486 NGM_LISTNODES,
487 "listnodes",
488 NULL,
489 &ng_generic_listnodes_type
490 },
491 {
492 NGM_GENERIC_COOKIE,
493 NGM_LISTTYPES,
494 "listtypes",
495 NULL,
496 &ng_generic_typeinfo_type
497 },
498 {
499 NGM_GENERIC_COOKIE,
500 NGM_TEXT_CONFIG,
501 "textconfig",
502 NULL,
503 &ng_parse_string_type
504 },
505 {
506 NGM_GENERIC_COOKIE,
507 NGM_TEXT_STATUS,
508 "textstatus",
509 NULL,
510 &ng_parse_string_type
511 },
512 {
513 NGM_GENERIC_COOKIE,
514 NGM_ASCII2BINARY,
515 "ascii2binary",
516 &ng_parse_ng_mesg_type,
517 &ng_parse_ng_mesg_type
518 },
519 {
520 NGM_GENERIC_COOKIE,
521 NGM_BINARY2ASCII,
522 "binary2ascii",
523 &ng_parse_ng_mesg_type,
524 &ng_parse_ng_mesg_type
525 },
526 { 0 }
527 };
528
529 /************************************************************************
530 Node routines
531 ************************************************************************/
532
533 /*
534 * Instantiate a node of the requested type
535 */
536 int
537 ng_make_node(const char *typename, node_p *nodepp)
538 {
539 struct ng_type *type;
540 int error;
541
542 /* Check that the type makes sense */
543 if (typename == NULL) {
544 TRAP_ERROR();
545 return (EINVAL);
546 }
547
548 /* Locate the node type. If we fail we return. Do not try to load
549 * module.
550 */
551 if ((type = ng_findtype(typename)) == NULL)
552 return (ENXIO);
553
554 /*
555 * If we have a constructor, then make the node and
556 * call the constructor to do type specific initialisation.
557 */
558 if (type->constructor != NULL) {
559 if ((error = ng_make_node_common(type, nodepp)) == 0) {
560 if ((error = ((*type->constructor)(*nodepp)) != 0)) {
561 NG_NODE_UNREF(*nodepp);
562 }
563 }
564 } else {
565 /*
566 * Node has no constructor. We cannot ask for one
567 * to be made. It must be brought into existance by
568 * some external agency. The external agency should
569 * call ng_make_node_common() directly to get the
570 * netgraph part initialised.
571 */
572 TRAP_ERROR();
573 error = EINVAL;
574 }
575 return (error);
576 }
577
578 /*
579 * Generic node creation. Called by node initialisation for externally
580 * instantiated nodes (e.g. hardware, sockets, etc ).
581 * The returned node has a reference count of 1.
582 */
583 int
584 ng_make_node_common(struct ng_type *type, node_p *nodepp)
585 {
586 node_p node;
587
588 /* Require the node type to have been already installed */
589 if (ng_findtype(type->name) == NULL) {
590 TRAP_ERROR();
591 return (EINVAL);
592 }
593
594 /* Make a node and try attach it to the type */
595 NG_ALLOC_NODE(node);
596 if (node == NULL) {
597 TRAP_ERROR();
598 return (ENOMEM);
599 }
600 node->nd_type = type;
601 NG_NODE_REF(node); /* note reference */
602 type->refs++;
603
604 mtx_init(&node->nd_input_queue.q_mtx, "ng_node", NULL, MTX_SPIN);
605 node->nd_input_queue.queue = NULL;
606 node->nd_input_queue.last = &node->nd_input_queue.queue;
607 node->nd_input_queue.q_flags = 0;
608 node->nd_input_queue.q_node = node;
609
610 /* Initialize hook list for new node */
611 LIST_INIT(&node->nd_hooks);
612
613 /* Link us into the node linked list */
614 mtx_lock(&ng_nodelist_mtx);
615 LIST_INSERT_HEAD(&ng_nodelist, node, nd_nodes);
616 mtx_unlock(&ng_nodelist_mtx);
617
618
619 /* get an ID and put us in the hash chain */
620 mtx_lock(&ng_idhash_mtx);
621 for (;;) { /* wrap protection, even if silly */
622 node_p node2 = NULL;
623 node->nd_ID = nextID++; /* 137/second for 1 year before wrap */
624
625 /* Is there a problem with the new number? */
626 NG_IDHASH_FIND(node->nd_ID, node2); /* already taken? */
627 if ((node->nd_ID != 0) && (node2 == NULL)) {
628 break;
629 }
630 }
631 LIST_INSERT_HEAD(&ng_ID_hash[NG_IDHASH_FN(node->nd_ID)],
632 node, nd_idnodes);
633 mtx_unlock(&ng_idhash_mtx);
634
635 /* Done */
636 *nodepp = node;
637 return (0);
638 }
639
640 /*
641 * Forceably start the shutdown process on a node. Either call
642 * it's shutdown method, or do the default shutdown if there is
643 * no type-specific method.
644 *
645 * We can only be called form a shutdown message, so we know we have
646 * a writer lock, and therefore exclusive access. It also means
647 * that we should not be on the work queue, but we check anyhow.
648 *
649 * Persistent node types must have a type-specific method which
650 * Allocates a new node in which case, this one is irretrievably going away,
651 * or cleans up anything it needs, and just makes the node valid again,
652 * in which case we allow the node to survive.
653 *
654 * XXX We need to think of how to tell a persistant node that we
655 * REALLY need to go away because the hardware has gone or we
656 * are rebooting.... etc.
657 */
658 void
659 ng_rmnode(node_p node, hook_p dummy1, void *dummy2, int dummy3)
660 {
661 hook_p hook;
662
663 /* Check if it's already shutting down */
664 if ((node->nd_flags & NGF_CLOSING) != 0)
665 return;
666
667 if (node == &ng_deadnode) {
668 printf ("shutdown called on deadnode\n");
669 return;
670 }
671
672 /* Add an extra reference so it doesn't go away during this */
673 NG_NODE_REF(node);
674
675 /*
676 * Mark it invalid so any newcomers know not to try use it
677 * Also add our own mark so we can't recurse
678 * note that NGF_INVALID does not do this as it's also set during
679 * creation
680 */
681 node->nd_flags |= NGF_INVALID|NGF_CLOSING;
682
683 /* If node has its pre-shutdown method, then call it first*/
684 if (node->nd_type && node->nd_type->close)
685 (*node->nd_type->close)(node);
686
687 /* Notify all remaining connected nodes to disconnect */
688 while ((hook = LIST_FIRST(&node->nd_hooks)) != NULL)
689 ng_destroy_hook(hook);
690
691 /*
692 * Drain the input queue forceably.
693 * it has no hooks so what's it going to do, bleed on someone?
694 * Theoretically we came here from a queue entry that was added
695 * Just before the queue was closed, so it should be empty anyway.
696 * Also removes us from worklist if needed.
697 */
698 ng_flush_input_queue(&node->nd_input_queue);
699
700 /* Ask the type if it has anything to do in this case */
701 if (node->nd_type && node->nd_type->shutdown) {
702 (*node->nd_type->shutdown)(node);
703 if (NG_NODE_IS_VALID(node)) {
704 /*
705 * Well, blow me down if the node code hasn't declared
706 * that it doesn't want to die.
707 * Presumably it is a persistant node.
708 * If we REALLY want it to go away,
709 * e.g. hardware going away,
710 * Our caller should set NGF_REALLY_DIE in nd_flags.
711 */
712 node->nd_flags &= ~(NGF_INVALID|NGF_CLOSING);
713 NG_NODE_UNREF(node); /* Assume they still have theirs */
714 return;
715 }
716 } else { /* do the default thing */
717 NG_NODE_UNREF(node);
718 }
719
720 ng_unname(node); /* basically a NOP these days */
721
722 /*
723 * Remove extra reference, possibly the last
724 * Possible other holders of references may include
725 * timeout callouts, but theoretically the node's supposed to
726 * have cancelled them. Possibly hardware dependencies may
727 * force a driver to 'linger' with a reference.
728 */
729 NG_NODE_UNREF(node);
730 }
731
732 #ifdef NETGRAPH_DEBUG
733 void
734 ng_ref_node(node_p node)
735 {
736 _NG_NODE_REF(node);
737 }
738 #endif
739
740 /*
741 * Remove a reference to the node, possibly the last.
742 * deadnode always acts as it it were the last.
743 */
744 int
745 ng_unref_node(node_p node)
746 {
747 int v;
748
749 if (node == &ng_deadnode) {
750 return (0);
751 }
752
753 do {
754 v = node->nd_refs - 1;
755 } while (! atomic_cmpset_int(&node->nd_refs, v + 1, v));
756
757 if (v == 0) { /* we were the last */
758
759 mtx_lock(&ng_nodelist_mtx);
760 node->nd_type->refs--; /* XXX maybe should get types lock? */
761 LIST_REMOVE(node, nd_nodes);
762 mtx_unlock(&ng_nodelist_mtx);
763
764 mtx_lock(&ng_idhash_mtx);
765 LIST_REMOVE(node, nd_idnodes);
766 mtx_unlock(&ng_idhash_mtx);
767
768 mtx_destroy(&node->nd_input_queue.q_mtx);
769 NG_FREE_NODE(node);
770 }
771 return (v);
772 }
773
774 /************************************************************************
775 Node ID handling
776 ************************************************************************/
777 static node_p
778 ng_ID2noderef(ng_ID_t ID)
779 {
780 node_p node;
781 mtx_lock(&ng_idhash_mtx);
782 NG_IDHASH_FIND(ID, node);
783 if(node)
784 NG_NODE_REF(node);
785 mtx_unlock(&ng_idhash_mtx);
786 return(node);
787 }
788
789 ng_ID_t
790 ng_node2ID(node_p node)
791 {
792 return (node ? NG_NODE_ID(node) : 0);
793 }
794
795 /************************************************************************
796 Node name handling
797 ************************************************************************/
798
799 /*
800 * Assign a node a name. Once assigned, the name cannot be changed.
801 */
802 int
803 ng_name_node(node_p node, const char *name)
804 {
805 int i;
806 node_p node2;
807
808 /* Check the name is valid */
809 for (i = 0; i < NG_NODESIZ; i++) {
810 if (name[i] == '\0' || name[i] == '.' || name[i] == ':')
811 break;
812 }
813 if (i == 0 || name[i] != '\0') {
814 TRAP_ERROR();
815 return (EINVAL);
816 }
817 if (ng_decodeidname(name) != 0) { /* valid IDs not allowed here */
818 TRAP_ERROR();
819 return (EINVAL);
820 }
821
822 /* Check the name isn't already being used */
823 if ((node2 = ng_name2noderef(node, name)) != NULL) {
824 NG_NODE_UNREF(node2);
825 TRAP_ERROR();
826 return (EADDRINUSE);
827 }
828
829 /* copy it */
830 strlcpy(NG_NODE_NAME(node), name, NG_NODESIZ);
831
832 return (0);
833 }
834
835 /*
836 * Find a node by absolute name. The name should NOT end with ':'
837 * The name "." means "this node" and "[xxx]" means "the node
838 * with ID (ie, at address) xxx".
839 *
840 * Returns the node if found, else NULL.
841 * Eventually should add something faster than a sequential search.
842 * Note it aquires a reference on the node so you can be sure it's still there.
843 */
844 node_p
845 ng_name2noderef(node_p here, const char *name)
846 {
847 node_p node;
848 ng_ID_t temp;
849
850 /* "." means "this node" */
851 if (strcmp(name, ".") == 0) {
852 NG_NODE_REF(here);
853 return(here);
854 }
855
856 /* Check for name-by-ID */
857 if ((temp = ng_decodeidname(name)) != 0) {
858 return (ng_ID2noderef(temp));
859 }
860
861 /* Find node by name */
862 mtx_lock(&ng_nodelist_mtx);
863 LIST_FOREACH(node, &ng_nodelist, nd_nodes) {
864 if (NG_NODE_IS_VALID(node)
865 && NG_NODE_HAS_NAME(node)
866 && (strcmp(NG_NODE_NAME(node), name) == 0)) {
867 break;
868 }
869 }
870 if (node)
871 NG_NODE_REF(node);
872 mtx_unlock(&ng_nodelist_mtx);
873 return (node);
874 }
875
876 /*
877 * Decode an ID name, eg. "[f03034de]". Returns 0 if the
878 * string is not valid, otherwise returns the value.
879 */
880 static ng_ID_t
881 ng_decodeidname(const char *name)
882 {
883 const int len = strlen(name);
884 char *eptr;
885 u_long val;
886
887 /* Check for proper length, brackets, no leading junk */
888 if ((len < 3)
889 || (name[0] != '[')
890 || (name[len - 1] != ']')
891 || (!isxdigit(name[1]))) {
892 return ((ng_ID_t)0);
893 }
894
895 /* Decode number */
896 val = strtoul(name + 1, &eptr, 16);
897 if ((eptr - name != len - 1)
898 || (val == ULONG_MAX)
899 || (val == 0)) {
900 return ((ng_ID_t)0);
901 }
902 return (ng_ID_t)val;
903 }
904
905 /*
906 * Remove a name from a node. This should only be called
907 * when shutting down and removing the node.
908 * IF we allow name changing this may be more resurected.
909 */
910 void
911 ng_unname(node_p node)
912 {
913 }
914
915 /************************************************************************
916 Hook routines
917 Names are not optional. Hooks are always connected, except for a
918 brief moment within these routines. On invalidation or during creation
919 they are connected to the 'dead' hook.
920 ************************************************************************/
921
922 /*
923 * Remove a hook reference
924 */
925 void
926 ng_unref_hook(hook_p hook)
927 {
928 int v;
929
930 if (hook == &ng_deadhook) {
931 return;
932 }
933 do {
934 v = hook->hk_refs;
935 } while (! atomic_cmpset_int(&hook->hk_refs, v, v - 1));
936
937 if (v == 1) { /* we were the last */
938 if (_NG_HOOK_NODE(hook)) { /* it'll probably be ng_deadnode */
939 _NG_NODE_UNREF((_NG_HOOK_NODE(hook)));
940 hook->hk_node = NULL;
941 }
942 NG_FREE_HOOK(hook);
943 }
944 }
945
946 /*
947 * Add an unconnected hook to a node. Only used internally.
948 * Assumes node is locked. (XXX not yet true )
949 */
950 static int
951 ng_add_hook(node_p node, const char *name, hook_p *hookp)
952 {
953 hook_p hook;
954 int error = 0;
955
956 /* Check that the given name is good */
957 if (name == NULL) {
958 TRAP_ERROR();
959 return (EINVAL);
960 }
961 if (ng_findhook(node, name) != NULL) {
962 TRAP_ERROR();
963 return (EEXIST);
964 }
965
966 /* Allocate the hook and link it up */
967 NG_ALLOC_HOOK(hook);
968 if (hook == NULL) {
969 TRAP_ERROR();
970 return (ENOMEM);
971 }
972 hook->hk_refs = 1; /* add a reference for us to return */
973 hook->hk_flags = HK_INVALID;
974 hook->hk_peer = &ng_deadhook; /* start off this way */
975 hook->hk_node = node;
976 NG_NODE_REF(node); /* each hook counts as a reference */
977
978 /* Set hook name */
979 strlcpy(NG_HOOK_NAME(hook), name, NG_HOOKSIZ);
980
981 /*
982 * Check if the node type code has something to say about it
983 * If it fails, the unref of the hook will also unref the node.
984 */
985 if (node->nd_type->newhook != NULL) {
986 if ((error = (*node->nd_type->newhook)(node, hook, name))) {
987 NG_HOOK_UNREF(hook); /* this frees the hook */
988 return (error);
989 }
990 }
991 /*
992 * The 'type' agrees so far, so go ahead and link it in.
993 * We'll ask again later when we actually connect the hooks.
994 */
995 LIST_INSERT_HEAD(&node->nd_hooks, hook, hk_hooks);
996 node->nd_numhooks++;
997 NG_HOOK_REF(hook); /* one for the node */
998
999 if (hookp)
1000 *hookp = hook;
1001 return (0);
1002 }
1003
1004 /*
1005 * Find a hook
1006 *
1007 * Node types may supply their own optimized routines for finding
1008 * hooks. If none is supplied, we just do a linear search.
1009 * XXX Possibly we should add a reference to the hook?
1010 */
1011 hook_p
1012 ng_findhook(node_p node, const char *name)
1013 {
1014 hook_p hook;
1015
1016 if (node->nd_type->findhook != NULL)
1017 return (*node->nd_type->findhook)(node, name);
1018 LIST_FOREACH(hook, &node->nd_hooks, hk_hooks) {
1019 if (NG_HOOK_IS_VALID(hook)
1020 && (strcmp(NG_HOOK_NAME(hook), name) == 0))
1021 return (hook);
1022 }
1023 return (NULL);
1024 }
1025
1026 /*
1027 * Destroy a hook
1028 *
1029 * As hooks are always attached, this really destroys two hooks.
1030 * The one given, and the one attached to it. Disconnect the hooks
1031 * from each other first. We reconnect the peer hook to the 'dead'
1032 * hook so that it can still exist after we depart. We then
1033 * send the peer its own destroy message. This ensures that we only
1034 * interact with the peer's structures when it is locked processing that
1035 * message. We hold a reference to the peer hook so we are guaranteed that
1036 * the peer hook and node are still going to exist until
1037 * we are finished there as the hook holds a ref on the node.
1038 * We run this same code again on the peer hook, but that time it is already
1039 * attached to the 'dead' hook.
1040 *
1041 * This routine is called at all stages of hook creation
1042 * on error detection and must be able to handle any such stage.
1043 */
1044 void
1045 ng_destroy_hook(hook_p hook)
1046 {
1047 hook_p peer = NG_HOOK_PEER(hook);
1048 node_p node = NG_HOOK_NODE(hook);
1049
1050 if (hook == &ng_deadhook) { /* better safe than sorry */
1051 printf("ng_destroy_hook called on deadhook\n");
1052 return;
1053 }
1054 hook->hk_flags |= HK_INVALID; /* as soon as possible */
1055 if (peer && (peer != &ng_deadhook)) {
1056 /*
1057 * Set the peer to point to ng_deadhook
1058 * from this moment on we are effectively independent it.
1059 * send it an rmhook message of it's own.
1060 */
1061 peer->hk_peer = &ng_deadhook; /* They no longer know us */
1062 hook->hk_peer = &ng_deadhook; /* Nor us, them */
1063 if (NG_HOOK_NODE(peer) == &ng_deadnode) {
1064 /*
1065 * If it's already divorced from a node,
1066 * just free it.
1067 */
1068 /* nothing */
1069 } else {
1070 ng_rmhook_self(peer); /* Send it a surprise */
1071 }
1072 NG_HOOK_UNREF(peer); /* account for peer link */
1073 NG_HOOK_UNREF(hook); /* account for peer link */
1074 }
1075
1076 /*
1077 * Remove the hook from the node's list to avoid possible recursion
1078 * in case the disconnection results in node shutdown.
1079 */
1080 if (node == &ng_deadnode) { /* happens if called from ng_con_nodes() */
1081 return;
1082 }
1083 LIST_REMOVE(hook, hk_hooks);
1084 node->nd_numhooks--;
1085 if (node->nd_type->disconnect) {
1086 /*
1087 * The type handler may elect to destroy the node so don't
1088 * trust its existance after this point. (except
1089 * that we still hold a reference on it. (which we
1090 * inherrited from the hook we are destroying)
1091 */
1092 (*node->nd_type->disconnect) (hook);
1093 }
1094
1095 /*
1096 * Note that because we will point to ng_deadnode, the original node
1097 * is not decremented automatically so we do that manually.
1098 */
1099 _NG_HOOK_NODE(hook) = &ng_deadnode;
1100 NG_NODE_UNREF(node); /* We no longer point to it so adjust count */
1101 NG_HOOK_UNREF(hook); /* Account for linkage (in list) to node */
1102 }
1103
1104 /*
1105 * Take two hooks on a node and merge the connection so that the given node
1106 * is effectively bypassed.
1107 */
1108 int
1109 ng_bypass(hook_p hook1, hook_p hook2)
1110 {
1111 if (hook1->hk_node != hook2->hk_node) {
1112 TRAP_ERROR();
1113 return (EINVAL);
1114 }
1115 hook1->hk_peer->hk_peer = hook2->hk_peer;
1116 hook2->hk_peer->hk_peer = hook1->hk_peer;
1117
1118 hook1->hk_peer = &ng_deadhook;
1119 hook2->hk_peer = &ng_deadhook;
1120
1121 /* XXX If we ever cache methods on hooks update them as well */
1122 ng_destroy_hook(hook1);
1123 ng_destroy_hook(hook2);
1124 return (0);
1125 }
1126
1127 /*
1128 * Install a new netgraph type
1129 */
1130 int
1131 ng_newtype(struct ng_type *tp)
1132 {
1133 const size_t namelen = strlen(tp->name);
1134
1135 /* Check version and type name fields */
1136 if ((tp->version != NG_ABI_VERSION)
1137 || (namelen == 0)
1138 || (namelen >= NG_TYPESIZ)) {
1139 TRAP_ERROR();
1140 if (tp->version != NG_ABI_VERSION) {
1141 printf("Netgraph: Node type rejected. ABI mismatch. Suggest recompile\n");
1142 }
1143 return (EINVAL);
1144 }
1145
1146 /* Check for name collision */
1147 if (ng_findtype(tp->name) != NULL) {
1148 TRAP_ERROR();
1149 return (EEXIST);
1150 }
1151
1152
1153 /* Link in new type */
1154 mtx_lock(&ng_typelist_mtx);
1155 LIST_INSERT_HEAD(&ng_typelist, tp, types);
1156 tp->refs = 1; /* first ref is linked list */
1157 mtx_unlock(&ng_typelist_mtx);
1158 return (0);
1159 }
1160
1161 /*
1162 * unlink a netgraph type
1163 * If no examples exist
1164 */
1165 int
1166 ng_rmtype(struct ng_type *tp)
1167 {
1168 /* Check for name collision */
1169 if (tp->refs != 1) {
1170 TRAP_ERROR();
1171 return (EBUSY);
1172 }
1173
1174 /* Unlink type */
1175 mtx_lock(&ng_typelist_mtx);
1176 LIST_REMOVE(tp, types);
1177 mtx_unlock(&ng_typelist_mtx);
1178 return (0);
1179 }
1180
1181 /*
1182 * Look for a type of the name given
1183 */
1184 struct ng_type *
1185 ng_findtype(const char *typename)
1186 {
1187 struct ng_type *type;
1188
1189 mtx_lock(&ng_typelist_mtx);
1190 LIST_FOREACH(type, &ng_typelist, types) {
1191 if (strcmp(type->name, typename) == 0)
1192 break;
1193 }
1194 mtx_unlock(&ng_typelist_mtx);
1195 return (type);
1196 }
1197
1198 /************************************************************************
1199 Composite routines
1200 ************************************************************************/
1201 /*
1202 * Connect two nodes using the specified hooks, using queued functions.
1203 */
1204 static void
1205 ng_con_part3(node_p node, hook_p hook, void *arg1, int arg2)
1206 {
1207
1208 /*
1209 * When we run, we know that the node 'node' is locked for us.
1210 * Our caller has a reference on the hook.
1211 * Our caller has a reference on the node.
1212 * (In this case our caller is ng_apply_item() ).
1213 * The peer hook has a reference on the hook.
1214 * We are all set up except for the final call to the node, and
1215 * the clearing of the INVALID flag.
1216 */
1217 if (NG_HOOK_NODE(hook) == &ng_deadnode) {
1218 /*
1219 * The node must have been freed again since we last visited
1220 * here. ng_destry_hook() has this effect but nothing else does.
1221 * We should just release our references and
1222 * free anything we can think of.
1223 * Since we know it's been destroyed, and it's our caller
1224 * that holds the references, just return.
1225 */
1226 return ;
1227 }
1228 if (hook->hk_node->nd_type->connect) {
1229 if ((*hook->hk_node->nd_type->connect) (hook)) {
1230 ng_destroy_hook(hook); /* also zaps peer */
1231 printf("failed in ng_con_part3()\n");
1232 return ;
1233 }
1234 }
1235 /*
1236 * XXX this is wrong for SMP. Possibly we need
1237 * to separate out 'create' and 'invalid' flags.
1238 * should only set flags on hooks we have locked under our node.
1239 */
1240 hook->hk_flags &= ~HK_INVALID;
1241 return ;
1242 }
1243
1244 static void
1245 ng_con_part2(node_p node, hook_p hook, void *arg1, int arg2)
1246 {
1247
1248 /*
1249 * When we run, we know that the node 'node' is locked for us.
1250 * Our caller has a reference on the hook.
1251 * Our caller has a reference on the node.
1252 * (In this case our caller is ng_apply_item() ).
1253 * The peer hook has a reference on the hook.
1254 * our node pointer points to the 'dead' node.
1255 * First check the hook name is unique.
1256 * Should not happen because we checked before queueing this.
1257 */
1258 if (ng_findhook(node, NG_HOOK_NAME(hook)) != NULL) {
1259 TRAP_ERROR();
1260 ng_destroy_hook(hook); /* should destroy peer too */
1261 printf("failed in ng_con_part2()\n");
1262 return ;
1263 }
1264 /*
1265 * Check if the node type code has something to say about it
1266 * If it fails, the unref of the hook will also unref the attached node,
1267 * however since that node is 'ng_deadnode' this will do nothing.
1268 * The peer hook will also be destroyed.
1269 */
1270 if (node->nd_type->newhook != NULL) {
1271 if ((*node->nd_type->newhook)(node, hook, hook->hk_name)) {
1272 ng_destroy_hook(hook); /* should destroy peer too */
1273 printf("failed in ng_con_part2()\n");
1274 return ;
1275 }
1276 }
1277
1278 /*
1279 * The 'type' agrees so far, so go ahead and link it in.
1280 * We'll ask again later when we actually connect the hooks.
1281 */
1282 hook->hk_node = node; /* just overwrite ng_deadnode */
1283 NG_NODE_REF(node); /* each hook counts as a reference */
1284 LIST_INSERT_HEAD(&node->nd_hooks, hook, hk_hooks);
1285 node->nd_numhooks++;
1286 NG_HOOK_REF(hook); /* one for the node */
1287
1288 /*
1289 * We now have a symetrical situation, where both hooks have been
1290 * linked to their nodes, the newhook methods have been called
1291 * And the references are all correct. The hooks are still marked
1292 * as invalid, as we have not called the 'connect' methods
1293 * yet.
1294 * We can call the local one immediatly as we have the
1295 * node locked, but we need to queue the remote one.
1296 */
1297 if (hook->hk_node->nd_type->connect) {
1298 if ((*hook->hk_node->nd_type->connect) (hook)) {
1299 ng_destroy_hook(hook); /* also zaps peer */
1300 printf("failed in ng_con_part2(A)\n");
1301 return ;
1302 }
1303 }
1304 if (ng_send_fn(hook->hk_peer->hk_node, hook->hk_peer,
1305 &ng_con_part3, arg1, arg2)) {
1306 printf("failed in ng_con_part2(B)");
1307 ng_destroy_hook(hook); /* also zaps peer */
1308 return ;
1309 }
1310 hook->hk_flags &= ~HK_INVALID; /* need both to be able to work */
1311 return ;
1312 }
1313
1314 /*
1315 * Connect this node with another node. We assume that this node is
1316 * currently locked, as we are only called from an NGM_CONNECT message.
1317 */
1318 static int
1319 ng_con_nodes(node_p node, const char *name, node_p node2, const char *name2)
1320 {
1321 int error;
1322 hook_p hook;
1323 hook_p hook2;
1324
1325 if (ng_findhook(node2, name2) != NULL) {
1326 return(EEXIST);
1327 }
1328 if ((error = ng_add_hook(node, name, &hook))) /* gives us a ref */
1329 return (error);
1330 /* Allocate the other hook and link it up */
1331 NG_ALLOC_HOOK(hook2);
1332 if (hook2 == NULL) {
1333 TRAP_ERROR();
1334 ng_destroy_hook(hook); /* XXX check ref counts so far */
1335 NG_HOOK_UNREF(hook); /* including our ref */
1336 return (ENOMEM);
1337 }
1338 hook2->hk_refs = 1; /* start with a reference for us. */
1339 hook2->hk_flags = HK_INVALID;
1340 hook2->hk_peer = hook; /* Link the two together */
1341 hook->hk_peer = hook2;
1342 NG_HOOK_REF(hook); /* Add a ref for the peer to each*/
1343 NG_HOOK_REF(hook2);
1344 hook2->hk_node = &ng_deadnode;
1345 strlcpy(NG_HOOK_NAME(hook2), name2, NG_HOOKSIZ);
1346
1347 /*
1348 * Queue the function above.
1349 * Procesing continues in that function in the lock context of
1350 * the other node.
1351 */
1352 ng_send_fn(node2, hook2, &ng_con_part2, NULL, 0);
1353
1354 NG_HOOK_UNREF(hook); /* Let each hook go if it wants to */
1355 NG_HOOK_UNREF(hook2);
1356 return (0);
1357 }
1358
1359 /*
1360 * Make a peer and connect.
1361 * We assume that the local node is locked.
1362 * The new node probably doesn't need a lock until
1363 * it has a hook, because it cannot really have any work until then,
1364 * but we should think about it a bit more.
1365 *
1366 * The problem may come if the other node also fires up
1367 * some hardware or a timer or some other source of activation,
1368 * also it may already get a command msg via it's ID.
1369 *
1370 * We could use the same method as ng_con_nodes() but we'd have
1371 * to add ability to remove the node when failing. (Not hard, just
1372 * make arg1 point to the node to remove).
1373 * Unless of course we just ignore failure to connect and leave
1374 * an unconnected node?
1375 */
1376 static int
1377 ng_mkpeer(node_p node, const char *name, const char *name2, char *type)
1378 {
1379 node_p node2;
1380 hook_p hook1;
1381 hook_p hook2;
1382 int error;
1383
1384 if ((error = ng_make_node(type, &node2))) {
1385 return (error);
1386 }
1387
1388 if ((error = ng_add_hook(node, name, &hook1))) { /* gives us a ref */
1389 ng_rmnode(node2, NULL, NULL, 0);
1390 return (error);
1391 }
1392
1393 if ((error = ng_add_hook(node2, name2, &hook2))) {
1394 ng_rmnode(node2, NULL, NULL, 0);
1395 ng_destroy_hook(hook1);
1396 NG_HOOK_UNREF(hook1);
1397 return (error);
1398 }
1399
1400 /*
1401 * Actually link the two hooks together.
1402 */
1403 hook1->hk_peer = hook2;
1404 hook2->hk_peer = hook1;
1405
1406 /* Each hook is referenced by the other */
1407 NG_HOOK_REF(hook1);
1408 NG_HOOK_REF(hook2);
1409
1410 /* Give each node the opportunity to veto the pending connection */
1411 if (hook1->hk_node->nd_type->connect) {
1412 error = (*hook1->hk_node->nd_type->connect) (hook1);
1413 }
1414
1415 if ((error == 0) && hook2->hk_node->nd_type->connect) {
1416 error = (*hook2->hk_node->nd_type->connect) (hook2);
1417
1418 }
1419
1420 /*
1421 * drop the references we were holding on the two hooks.
1422 */
1423 if (error) {
1424 ng_destroy_hook(hook2); /* also zaps hook1 */
1425 ng_rmnode(node2, NULL, NULL, 0);
1426 } else {
1427 /* As a last act, allow the hooks to be used */
1428 hook1->hk_flags &= ~HK_INVALID;
1429 hook2->hk_flags &= ~HK_INVALID;
1430 }
1431 NG_HOOK_UNREF(hook1);
1432 NG_HOOK_UNREF(hook2);
1433 return (error);
1434 }
1435
1436 /************************************************************************
1437 Utility routines to send self messages
1438 ************************************************************************/
1439
1440 /* Shut this node down as soon as everyone is clear of it */
1441 /* Should add arg "immediatly" to jump the queue */
1442 int
1443 ng_rmnode_self(node_p node)
1444 {
1445 int error;
1446
1447 if (node == &ng_deadnode)
1448 return (0);
1449 node->nd_flags |= NGF_INVALID;
1450 if (node->nd_flags & NGF_CLOSING)
1451 return (0);
1452
1453 error = ng_send_fn(node, NULL, &ng_rmnode, NULL, 0);
1454 return (error);
1455 }
1456
1457 static void
1458 ng_rmhook_part2(node_p node, hook_p hook, void *arg1, int arg2)
1459 {
1460 ng_destroy_hook(hook);
1461 return ;
1462 }
1463
1464 int
1465 ng_rmhook_self(hook_p hook)
1466 {
1467 int error;
1468 node_p node = NG_HOOK_NODE(hook);
1469
1470 if (node == &ng_deadnode)
1471 return (0);
1472
1473 error = ng_send_fn(node, hook, &ng_rmhook_part2, NULL, 0);
1474 return (error);
1475 }
1476
1477 /***********************************************************************
1478 * Parse and verify a string of the form: <NODE:><PATH>
1479 *
1480 * Such a string can refer to a specific node or a specific hook
1481 * on a specific node, depending on how you look at it. In the
1482 * latter case, the PATH component must not end in a dot.
1483 *
1484 * Both <NODE:> and <PATH> are optional. The <PATH> is a string
1485 * of hook names separated by dots. This breaks out the original
1486 * string, setting *nodep to "NODE" (or NULL if none) and *pathp
1487 * to "PATH" (or NULL if degenerate). Also, *hookp will point to
1488 * the final hook component of <PATH>, if any, otherwise NULL.
1489 *
1490 * This returns -1 if the path is malformed. The char ** are optional.
1491 ***********************************************************************/
1492 int
1493 ng_path_parse(char *addr, char **nodep, char **pathp, char **hookp)
1494 {
1495 char *node, *path, *hook;
1496 int k;
1497
1498 /*
1499 * Extract absolute NODE, if any
1500 */
1501 for (path = addr; *path && *path != ':'; path++);
1502 if (*path) {
1503 node = addr; /* Here's the NODE */
1504 *path++ = '\0'; /* Here's the PATH */
1505
1506 /* Node name must not be empty */
1507 if (!*node)
1508 return -1;
1509
1510 /* A name of "." is OK; otherwise '.' not allowed */
1511 if (strcmp(node, ".") != 0) {
1512 for (k = 0; node[k]; k++)
1513 if (node[k] == '.')
1514 return -1;
1515 }
1516 } else {
1517 node = NULL; /* No absolute NODE */
1518 path = addr; /* Here's the PATH */
1519 }
1520
1521 /* Snoop for illegal characters in PATH */
1522 for (k = 0; path[k]; k++)
1523 if (path[k] == ':')
1524 return -1;
1525
1526 /* Check for no repeated dots in PATH */
1527 for (k = 0; path[k]; k++)
1528 if (path[k] == '.' && path[k + 1] == '.')
1529 return -1;
1530
1531 /* Remove extra (degenerate) dots from beginning or end of PATH */
1532 if (path[0] == '.')
1533 path++;
1534 if (*path && path[strlen(path) - 1] == '.')
1535 path[strlen(path) - 1] = 0;
1536
1537 /* If PATH has a dot, then we're not talking about a hook */
1538 if (*path) {
1539 for (hook = path, k = 0; path[k]; k++)
1540 if (path[k] == '.') {
1541 hook = NULL;
1542 break;
1543 }
1544 } else
1545 path = hook = NULL;
1546
1547 /* Done */
1548 if (nodep)
1549 *nodep = node;
1550 if (pathp)
1551 *pathp = path;
1552 if (hookp)
1553 *hookp = hook;
1554 return (0);
1555 }
1556
1557 /*
1558 * Given a path, which may be absolute or relative, and a starting node,
1559 * return the destination node.
1560 */
1561 int
1562 ng_path2noderef(node_p here, const char *address,
1563 node_p *destp, hook_p *lasthook)
1564 {
1565 char fullpath[NG_PATHSIZ];
1566 char *nodename, *path, pbuf[2];
1567 node_p node, oldnode;
1568 char *cp;
1569 hook_p hook = NULL;
1570
1571 /* Initialize */
1572 if (destp == NULL) {
1573 TRAP_ERROR();
1574 return EINVAL;
1575 }
1576 *destp = NULL;
1577
1578 /* Make a writable copy of address for ng_path_parse() */
1579 strncpy(fullpath, address, sizeof(fullpath) - 1);
1580 fullpath[sizeof(fullpath) - 1] = '\0';
1581
1582 /* Parse out node and sequence of hooks */
1583 if (ng_path_parse(fullpath, &nodename, &path, NULL) < 0) {
1584 TRAP_ERROR();
1585 return EINVAL;
1586 }
1587 if (path == NULL) {
1588 pbuf[0] = '.'; /* Needs to be writable */
1589 pbuf[1] = '\0';
1590 path = pbuf;
1591 }
1592
1593 /*
1594 * For an absolute address, jump to the starting node.
1595 * Note that this holds a reference on the node for us.
1596 * Don't forget to drop the reference if we don't need it.
1597 */
1598 if (nodename) {
1599 node = ng_name2noderef(here, nodename);
1600 if (node == NULL) {
1601 TRAP_ERROR();
1602 return (ENOENT);
1603 }
1604 } else {
1605 if (here == NULL) {
1606 TRAP_ERROR();
1607 return (EINVAL);
1608 }
1609 node = here;
1610 NG_NODE_REF(node);
1611 }
1612
1613 /*
1614 * Now follow the sequence of hooks
1615 * XXX
1616 * We actually cannot guarantee that the sequence
1617 * is not being demolished as we crawl along it
1618 * without extra-ordinary locking etc.
1619 * So this is a bit dodgy to say the least.
1620 * We can probably hold up some things by holding
1621 * the nodelist mutex for the time of this
1622 * crawl if we wanted.. At least that way we wouldn't have to
1623 * worry about the nodes dissappearing, but the hooks would still
1624 * be a problem.
1625 */
1626 for (cp = path; node != NULL && *cp != '\0'; ) {
1627 char *segment;
1628
1629 /*
1630 * Break out the next path segment. Replace the dot we just
1631 * found with a NUL; "cp" points to the next segment (or the
1632 * NUL at the end).
1633 */
1634 for (segment = cp; *cp != '\0'; cp++) {
1635 if (*cp == '.') {
1636 *cp++ = '\0';
1637 break;
1638 }
1639 }
1640
1641 /* Empty segment */
1642 if (*segment == '\0')
1643 continue;
1644
1645 /* We have a segment, so look for a hook by that name */
1646 hook = ng_findhook(node, segment);
1647
1648 /* Can't get there from here... */
1649 if (hook == NULL
1650 || NG_HOOK_PEER(hook) == NULL
1651 || NG_HOOK_NOT_VALID(hook)
1652 || NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook))) {
1653 TRAP_ERROR();
1654 NG_NODE_UNREF(node);
1655 #if 0
1656 printf("hooknotvalid %s %s %d %d %d %d ",
1657 path,
1658 segment,
1659 hook == NULL,
1660 NG_HOOK_PEER(hook) == NULL,
1661 NG_HOOK_NOT_VALID(hook),
1662 NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook)));
1663 #endif
1664 return (ENOENT);
1665 }
1666
1667 /*
1668 * Hop on over to the next node
1669 * XXX
1670 * Big race conditions here as hooks and nodes go away
1671 * *** Idea.. store an ng_ID_t in each hook and use that
1672 * instead of the direct hook in this crawl?
1673 */
1674 oldnode = node;
1675 if ((node = NG_PEER_NODE(hook)))
1676 NG_NODE_REF(node); /* XXX RACE */
1677 NG_NODE_UNREF(oldnode); /* XXX another race */
1678 if (NG_NODE_NOT_VALID(node)) {
1679 NG_NODE_UNREF(node); /* XXX more races */
1680 node = NULL;
1681 }
1682 }
1683
1684 /* If node somehow missing, fail here (probably this is not needed) */
1685 if (node == NULL) {
1686 TRAP_ERROR();
1687 return (ENXIO);
1688 }
1689
1690 /* Done */
1691 *destp = node;
1692 if (lasthook != NULL)
1693 *lasthook = (hook ? NG_HOOK_PEER(hook) : NULL);
1694 return (0);
1695 }
1696
1697 /***************************************************************\
1698 * Input queue handling.
1699 * All activities are submitted to the node via the input queue
1700 * which implements a multiple-reader/single-writer gate.
1701 * Items which cannot be handled immeditly are queued.
1702 *
1703 * read-write queue locking inline functions *
1704 \***************************************************************/
1705
1706 static __inline item_p ng_dequeue(struct ng_queue * ngq);
1707 static __inline item_p ng_acquire_read(struct ng_queue * ngq,
1708 item_p item);
1709 static __inline item_p ng_acquire_write(struct ng_queue * ngq,
1710 item_p item);
1711 static __inline void ng_leave_read(struct ng_queue * ngq);
1712 static __inline void ng_leave_write(struct ng_queue * ngq);
1713 static __inline void ng_queue_rw(struct ng_queue * ngq,
1714 item_p item, int rw);
1715
1716 /*
1717 * Definition of the bits fields in the ng_queue flag word.
1718 * Defined here rather than in netgraph.h because no-one should fiddle
1719 * with them.
1720 *
1721 * The ordering here may be important! don't shuffle these.
1722 */
1723 /*-
1724 Safety Barrier--------+ (adjustable to suit taste) (not used yet)
1725 |
1726 V
1727 +-------+-------+-------+-------+-------+-------+-------+-------+
1728 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
1729 | |A|c|t|i|v|e| |R|e|a|d|e|r| |C|o|u|n|t| | | | | | | | | |R|A|W|
1730 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |P|W|P|
1731 +-------+-------+-------+-------+-------+-------+-------+-------+
1732 \___________________________ ____________________________/ | | |
1733 V | | |
1734 [active reader count] | | |
1735 | | |
1736 Read Pending ------------------------------------+ | |
1737 | |
1738 Active Writer -------------------------------------+ |
1739 |
1740 Write Pending ---------------------------------------+
1741
1742
1743 */
1744 #define WRITE_PENDING 0x00000001
1745 #define WRITER_ACTIVE 0x00000002
1746 #define READ_PENDING 0x00000004
1747 #define READER_INCREMENT 0x00000008
1748 #define READER_MASK 0xfffffff8 /* Not valid if WRITER_ACTIVE is set */
1749 #define SAFETY_BARRIER 0x00100000 /* 64K items queued should be enough */
1750
1751 /* Defines of more elaborate states on the queue */
1752 /* Mask of bits a read cares about */
1753 #define NGQ_RMASK (WRITE_PENDING|WRITER_ACTIVE|READ_PENDING)
1754
1755 /* Mask of bits a write cares about */
1756 #define NGQ_WMASK (NGQ_RMASK|READER_MASK)
1757
1758 /* tests to decide if we could get a read or write off the queue */
1759 #define CAN_GET_READ(flag) ((flag & NGQ_RMASK) == READ_PENDING)
1760 #define CAN_GET_WRITE(flag) ((flag & NGQ_WMASK) == WRITE_PENDING)
1761
1762 /* Is there a chance of getting ANY work off the queue? */
1763 #define CAN_GET_WORK(flag) (CAN_GET_READ(flag) || CAN_GET_WRITE(flag))
1764
1765 /*
1766 * Taking into account the current state of the queue and node, possibly take
1767 * the next entry off the queue and return it. Return NULL if there was
1768 * nothing we could return, either because there really was nothing there, or
1769 * because the node was in a state where it cannot yet process the next item
1770 * on the queue.
1771 *
1772 * This MUST MUST MUST be called with the mutex held.
1773 */
1774 static __inline item_p
1775 ng_dequeue(struct ng_queue *ngq)
1776 {
1777 item_p item;
1778 u_int add_arg;
1779
1780 mtx_assert(&ngq->q_mtx, MA_OWNED);
1781
1782 if (CAN_GET_READ(ngq->q_flags)) {
1783 /*
1784 * Head of queue is a reader and we have no write active.
1785 * We don't care how many readers are already active.
1786 * Adjust the flags for the item we are about to dequeue.
1787 * Add the correct increment for the reader count as well.
1788 */
1789 add_arg = (READER_INCREMENT - READ_PENDING);
1790 } else if (CAN_GET_WRITE(ngq->q_flags)) {
1791 /*
1792 * There is a pending write, no readers and no active writer.
1793 * This means we can go ahead with the pending writer. Note
1794 * the fact that we now have a writer, ready for when we take
1795 * it off the queue.
1796 *
1797 * We don't need to worry about a possible collision with the
1798 * fasttrack reader.
1799 *
1800 * The fasttrack thread may take a long time to discover that we
1801 * are running so we would have an inconsistent state in the
1802 * flags for a while. Since we ignore the reader count
1803 * entirely when the WRITER_ACTIVE flag is set, this should
1804 * not matter (in fact it is defined that way). If it tests
1805 * the flag before this operation, the WRITE_PENDING flag
1806 * will make it fail, and if it tests it later, the
1807 * WRITER_ACTIVE flag will do the same. If it is SO slow that
1808 * we have actually completed the operation, and neither flag
1809 * is set (nor the READ_PENDING) by the time that it tests
1810 * the flags, then it is actually ok for it to continue. If
1811 * it completes and we've finished and the read pending is
1812 * set it still fails.
1813 *
1814 * So we can just ignore it, as long as we can ensure that the
1815 * transition from WRITE_PENDING state to the WRITER_ACTIVE
1816 * state is atomic.
1817 *
1818 * After failing, first it will be held back by the mutex, then
1819 * when it can proceed, it will queue its request, then it
1820 * would arrive at this function. Usually it will have to
1821 * leave empty handed because the ACTIVE WRITER bit will be
1822 * set.
1823 *
1824 * Adjust the flags for the item we are about to dequeue
1825 * and for the new active writer.
1826 */
1827 add_arg = (WRITER_ACTIVE - WRITE_PENDING);
1828 /*
1829 * We want to write "active writer, no readers " Now go make
1830 * it true. In fact there may be a number in the readers
1831 * count but we know it is not true and will be fixed soon.
1832 * We will fix the flags for the next pending entry in a
1833 * moment.
1834 */
1835 } else {
1836 /*
1837 * We can't dequeue anything.. return and say so. Probably we
1838 * have a write pending and the readers count is non zero. If
1839 * we got here because a reader hit us just at the wrong
1840 * moment with the fasttrack code, and put us in a strange
1841 * state, then it will be through in just a moment, (as soon
1842 * as we release the mutex) and keep things moving.
1843 * Make sure we remove ourselves from the work queue.
1844 */
1845 ng_worklist_remove(ngq->q_node);
1846 return (0);
1847 }
1848
1849 /*
1850 * Now we dequeue the request (whatever it may be) and correct the
1851 * pending flags and the next and last pointers.
1852 */
1853 item = ngq->queue;
1854 ngq->queue = item->el_next;
1855 if (ngq->last == &(item->el_next)) {
1856 /*
1857 * that was the last entry in the queue so set the 'last
1858 * pointer up correctly and make sure the pending flags are
1859 * clear.
1860 */
1861 ngq->last = &(ngq->queue);
1862 /*
1863 * Whatever flag was set will be cleared and
1864 * the new acive field will be set by the add as well,
1865 * so we don't need to change add_arg.
1866 * But we know we don't need to be on the work list.
1867 */
1868 atomic_add_long(&ngq->q_flags, add_arg);
1869 ng_worklist_remove(ngq->q_node);
1870 } else {
1871 /*
1872 * Since there is something on the queue, note what it is
1873 * in the flags word.
1874 */
1875 if ((ngq->queue->el_flags & NGQF_RW) == NGQF_READER) {
1876 add_arg += READ_PENDING;
1877 } else {
1878 add_arg += WRITE_PENDING;
1879 }
1880 atomic_add_long(&ngq->q_flags, add_arg);
1881 /*
1882 * If we see more doable work, make sure we are
1883 * on the work queue.
1884 */
1885 if (CAN_GET_WORK(ngq->q_flags)) {
1886 ng_setisr(ngq->q_node);
1887 }
1888 }
1889 /*
1890 * We have successfully cleared the old pending flag, set the new one
1891 * if it is needed, and incremented the appropriate active field.
1892 * (all in one atomic addition.. )
1893 */
1894 return (item);
1895 }
1896
1897 /*
1898 * Queue a packet to be picked up by someone else.
1899 * We really don't care who, but we can't or don't want to hang around
1900 * to process it ourselves. We are probably an interrupt routine..
1901 * 1 = writer, 0 = reader
1902 */
1903 #define NGQRW_R 0
1904 #define NGQRW_W 1
1905 static __inline void
1906 ng_queue_rw(struct ng_queue * ngq, item_p item, int rw)
1907 {
1908 mtx_assert(&ngq->q_mtx, MA_OWNED);
1909
1910 item->el_next = NULL; /* maybe not needed */
1911 *ngq->last = item;
1912 /*
1913 * If it was the first item in the queue then we need to
1914 * set the last pointer and the type flags.
1915 */
1916 if (ngq->last == &(ngq->queue)) {
1917 /*
1918 * When called with constants for rw, the optimiser will
1919 * remove the unneeded branch below.
1920 */
1921 if (rw == NGQRW_W) {
1922 atomic_add_long(&ngq->q_flags, WRITE_PENDING);
1923 } else {
1924 atomic_add_long(&ngq->q_flags, READ_PENDING);
1925 }
1926 }
1927 ngq->last = &(item->el_next);
1928 }
1929
1930
1931 /*
1932 * This function 'cheats' in that it first tries to 'grab' the use of the
1933 * node, without going through the mutex. We can do this becasue of the
1934 * semantics of the lock. The semantics include a clause that says that the
1935 * value of the readers count is invalid if the WRITER_ACTIVE flag is set. It
1936 * also says that the WRITER_ACTIVE flag cannot be set if the readers count
1937 * is not zero. Note that this talks about what is valid to SET the
1938 * WRITER_ACTIVE flag, because from the moment it is set, the value if the
1939 * reader count is immaterial, and not valid. The two 'pending' flags have a
1940 * similar effect, in that If they are orthogonal to the two active fields in
1941 * how they are set, but if either is set, the attempted 'grab' need to be
1942 * backed out because there is earlier work, and we maintain ordering in the
1943 * queue. The result of this is that the reader request can try obtain use of
1944 * the node with only a single atomic addition, and without any of the mutex
1945 * overhead. If this fails the operation degenerates to the same as for other
1946 * cases.
1947 *
1948 */
1949 static __inline item_p
1950 ng_acquire_read(struct ng_queue *ngq, item_p item)
1951 {
1952
1953 /* ######### Hack alert ######### */
1954 atomic_add_long(&ngq->q_flags, READER_INCREMENT);
1955 if ((ngq->q_flags & NGQ_RMASK) == 0) {
1956 /* Successfully grabbed node */
1957 return (item);
1958 }
1959 /* undo the damage if we didn't succeed */
1960 atomic_subtract_long(&ngq->q_flags, READER_INCREMENT);
1961
1962 /* ######### End Hack alert ######### */
1963 mtx_lock_spin((&ngq->q_mtx));
1964 /*
1965 * Try again. Another processor (or interrupt for that matter) may
1966 * have removed the last queued item that was stopping us from
1967 * running, between the previous test, and the moment that we took
1968 * the mutex. (Or maybe a writer completed.)
1969 */
1970 if ((ngq->q_flags & NGQ_RMASK) == 0) {
1971 atomic_add_long(&ngq->q_flags, READER_INCREMENT);
1972 mtx_unlock_spin((&ngq->q_mtx));
1973 return (item);
1974 }
1975
1976 /*
1977 * and queue the request for later.
1978 */
1979 item->el_flags |= NGQF_READER;
1980 ng_queue_rw(ngq, item, NGQRW_R);
1981 if (CAN_GET_WORK(ngq->q_flags))
1982 ng_setisr(ngq->q_node);
1983 mtx_unlock_spin(&(ngq->q_mtx));
1984
1985 return (NULL);
1986 }
1987
1988 static __inline item_p
1989 ng_acquire_write(struct ng_queue *ngq, item_p item)
1990 {
1991 restart:
1992 mtx_lock_spin(&(ngq->q_mtx));
1993 /*
1994 * If there are no readers, no writer, and no pending packets, then
1995 * we can just go ahead. In all other situations we need to queue the
1996 * request
1997 */
1998 if ((ngq->q_flags & NGQ_WMASK) == 0) {
1999 atomic_add_long(&ngq->q_flags, WRITER_ACTIVE);
2000 mtx_unlock_spin((&ngq->q_mtx));
2001 if (ngq->q_flags & READER_MASK) {
2002 /* Collision with fast-track reader */
2003 atomic_subtract_long(&ngq->q_flags, WRITER_ACTIVE);
2004 goto restart;
2005 }
2006 return (item);
2007 }
2008
2009 /*
2010 * and queue the request for later.
2011 */
2012 item->el_flags &= ~NGQF_RW;
2013 ng_queue_rw(ngq, item, NGQRW_W);
2014 if (CAN_GET_WORK(ngq->q_flags))
2015 ng_setisr(ngq->q_node);
2016 mtx_unlock_spin(&(ngq->q_mtx));
2017
2018 return (NULL);
2019 }
2020
2021 static __inline void
2022 ng_leave_read(struct ng_queue *ngq)
2023 {
2024 atomic_subtract_long(&ngq->q_flags, READER_INCREMENT);
2025 }
2026
2027 static __inline void
2028 ng_leave_write(struct ng_queue *ngq)
2029 {
2030 atomic_subtract_long(&ngq->q_flags, WRITER_ACTIVE);
2031 }
2032
2033 static void
2034 ng_flush_input_queue(struct ng_queue * ngq)
2035 {
2036 item_p item;
2037 u_int add_arg;
2038 mtx_lock_spin(&ngq->q_mtx);
2039 for (;;) {
2040 /* Now take a look at what's on the queue */
2041 if (ngq->q_flags & READ_PENDING) {
2042 add_arg = -READ_PENDING;
2043 } else if (ngq->q_flags & WRITE_PENDING) {
2044 add_arg = -WRITE_PENDING;
2045 } else {
2046 break;
2047 }
2048
2049 item = ngq->queue;
2050 ngq->queue = item->el_next;
2051 if (ngq->last == &(item->el_next)) {
2052 ngq->last = &(ngq->queue);
2053 } else {
2054 if ((ngq->queue->el_flags & NGQF_RW) == NGQF_READER) {
2055 add_arg += READ_PENDING;
2056 } else {
2057 add_arg += WRITE_PENDING;
2058 }
2059 }
2060 atomic_add_long(&ngq->q_flags, add_arg);
2061
2062 mtx_unlock_spin(&ngq->q_mtx);
2063 NG_FREE_ITEM(item);
2064 mtx_lock_spin(&ngq->q_mtx);
2065 }
2066 /*
2067 * Take us off the work queue if we are there.
2068 * We definatly have no work to be done.
2069 */
2070 ng_worklist_remove(ngq->q_node);
2071 mtx_unlock_spin(&ngq->q_mtx);
2072 }
2073
2074 /***********************************************************************
2075 * Externally visible method for sending or queueing messages or data.
2076 ***********************************************************************/
2077
2078 /*
2079 * The module code should have filled out the item correctly by this stage:
2080 * Common:
2081 * reference to destination node.
2082 * Reference to destination rcv hook if relevant.
2083 * Data:
2084 * pointer to mbuf
2085 * Control_Message:
2086 * pointer to msg.
2087 * ID of original sender node. (return address)
2088 * Function:
2089 * Function pointer
2090 * void * argument
2091 * integer argument
2092 *
2093 * The nodes have several routines and macros to help with this task:
2094 */
2095
2096 int
2097 ng_snd_item(item_p item, int flags)
2098 {
2099 hook_p hook = NGI_HOOK(item);
2100 node_p node = NGI_NODE(item);
2101 int queue, rw;
2102 int error = 0, ierror;
2103 item_p oitem;
2104 struct ng_queue * ngq = &node->nd_input_queue;
2105
2106 #ifdef NETGRAPH_DEBUG
2107 _ngi_check(item, __FILE__, __LINE__);
2108 #endif
2109
2110 queue = (flags & NG_QUEUE) ? 1 : 0;
2111
2112 if (item == NULL) {
2113 TRAP_ERROR();
2114 return (EINVAL); /* failed to get queue element */
2115 }
2116 if (node == NULL) {
2117 NG_FREE_ITEM(item);
2118 TRAP_ERROR();
2119 return (EINVAL); /* No address */
2120 }
2121 switch(item->el_flags & NGQF_TYPE) {
2122 case NGQF_DATA:
2123 /*
2124 * DATA MESSAGE
2125 * Delivered to a node via a non-optional hook.
2126 * Both should be present in the item even though
2127 * the node is derivable from the hook.
2128 * References are held on both by the item.
2129 */
2130
2131 /* Protect nodes from sending NULL pointers
2132 * to each other
2133 */
2134 if (NGI_M(item) == NULL)
2135 return (EINVAL);
2136
2137 CHECK_DATA_MBUF(NGI_M(item));
2138 if (hook == NULL) {
2139 NG_FREE_ITEM(item);
2140 TRAP_ERROR();
2141 return(EINVAL);
2142 }
2143 if ((NG_HOOK_NOT_VALID(hook))
2144 || (NG_NODE_NOT_VALID(NG_HOOK_NODE(hook)))) {
2145 NG_FREE_ITEM(item);
2146 return (ENOTCONN);
2147 }
2148 if ((hook->hk_flags & HK_QUEUE)) {
2149 queue = 1;
2150 }
2151 /* By default data is a reader in the locking scheme */
2152 item->el_flags |= NGQF_READER;
2153 rw = NGQRW_R;
2154 break;
2155 case NGQF_MESG:
2156 /*
2157 * CONTROL MESSAGE
2158 * Delivered to a node.
2159 * Hook is optional.
2160 * References are held by the item on the node and
2161 * the hook if it is present.
2162 */
2163 if (hook && (hook->hk_flags & HK_QUEUE)) {
2164 queue = 1;
2165 }
2166 /* Data messages count as writers unles explicitly exempted */
2167 if (NGI_MSG(item)->header.cmd & NGM_READONLY) {
2168 item->el_flags |= NGQF_READER;
2169 rw = NGQRW_R;
2170 } else {
2171 item->el_flags &= ~NGQF_RW;
2172 rw = NGQRW_W;
2173 }
2174 break;
2175 case NGQF_FN:
2176 item->el_flags &= ~NGQF_RW;
2177 rw = NGQRW_W;
2178 break;
2179 default:
2180 NG_FREE_ITEM(item);
2181 TRAP_ERROR();
2182 return (EINVAL);
2183 }
2184 /*
2185 * If the node specifies single threading, force writer semantics
2186 * Similarly the node may say one hook always produces writers.
2187 * These are over-rides.
2188 */
2189 if ((node->nd_flags & NGF_FORCE_WRITER)
2190 || (hook && (hook->hk_flags & HK_FORCE_WRITER))) {
2191 rw = NGQRW_W;
2192 item->el_flags &= ~NGQF_READER;
2193 }
2194 if (queue) {
2195 /* Put it on the queue for that node*/
2196 #ifdef NETGRAPH_DEBUG
2197 _ngi_check(item, __FILE__, __LINE__);
2198 #endif
2199 mtx_lock_spin(&(ngq->q_mtx));
2200 ng_queue_rw(ngq, item, rw);
2201 /*
2202 * If there are active elements then we can rely on
2203 * them. if not we should not rely on another packet
2204 * coming here by another path,
2205 * so it is best to put us in the netisr list.
2206 * We can take the worklist lock with the node locked
2207 * BUT NOT THE REVERSE!
2208 */
2209 if (CAN_GET_WORK(ngq->q_flags)) {
2210 ng_setisr(node);
2211 }
2212 mtx_unlock_spin(&(ngq->q_mtx));
2213
2214 if (flags & NG_PROGRESS)
2215 return (EINPROGRESS);
2216 else
2217 return (0);
2218 }
2219 /*
2220 * Take a queue item and a node and see if we can apply the item to
2221 * the node. We may end up getting a different item to apply instead.
2222 * Will allow for a piggyback reply only in the case where
2223 * there is no queueing.
2224 */
2225
2226 oitem = item;
2227 /*
2228 * We already decided how we will be queueud or treated.
2229 * Try get the appropriate operating permission.
2230 */
2231 if (rw == NGQRW_R) {
2232 item = ng_acquire_read(ngq, item);
2233 } else {
2234 item = ng_acquire_write(ngq, item);
2235 }
2236
2237 /*
2238 * May have come back with a different item.
2239 * or maybe none at all. The one we started with will
2240 * have been queued in thises cases.
2241 */
2242 if (item == NULL) {
2243 if (flags & NG_PROGRESS)
2244 return (EINPROGRESS);
2245 else
2246 return (0);
2247 }
2248
2249 #ifdef NETGRAPH_DEBUG
2250 _ngi_check(item, __FILE__, __LINE__);
2251 #endif
2252 /*
2253 * Take over the reference frm the item.
2254 * Hold it until the called function returns.
2255 */
2256 NGI_GET_NODE(item, node); /* zaps stored node */
2257
2258 ierror = ng_apply_item(node, item); /* drops r/w lock when done */
2259
2260 /* only return an error if it was our initial item.. (compat hack) */
2261 if (oitem == item) {
2262 error = ierror;
2263 }
2264
2265 /*
2266 * If the node goes away when we remove the reference,
2267 * whatever we just did caused it.. whatever we do, DO NOT
2268 * access the node again!
2269 */
2270 if (NG_NODE_UNREF(node) == 0) {
2271 return (error);
2272 }
2273
2274 mtx_lock_spin(&(ngq->q_mtx));
2275 if (CAN_GET_WORK(ngq->q_flags))
2276 ng_setisr(ngq->q_node);
2277 mtx_unlock_spin(&(ngq->q_mtx));
2278
2279 return (error);
2280 }
2281
2282 /*
2283 * We have an item that was possibly queued somewhere.
2284 * It should contain all the information needed
2285 * to run it on the appropriate node/hook.
2286 */
2287 static int
2288 ng_apply_item(node_p node, item_p item)
2289 {
2290 hook_p hook;
2291 int was_reader = ((item->el_flags & NGQF_RW));
2292 int error = 0;
2293 ng_rcvdata_t *rcvdata;
2294 ng_rcvmsg_t *rcvmsg;
2295 ng_apply_t *apply = NULL;
2296 void *context = NULL;
2297
2298 NGI_GET_HOOK(item, hook); /* clears stored hook */
2299 #ifdef NETGRAPH_DEBUG
2300 _ngi_check(item, __FILE__, __LINE__);
2301 #endif
2302
2303 /*
2304 * If item has apply callback, store it. Clear callback
2305 * immediately, two avoid another call in case if
2306 * item would be reused by destination node.
2307 */
2308 if (item->apply != NULL) {
2309 apply = item->apply;
2310 context = item->context;
2311 item->apply = NULL;
2312 }
2313
2314 switch (item->el_flags & NGQF_TYPE) {
2315 case NGQF_DATA:
2316 /*
2317 * Check things are still ok as when we were queued.
2318 */
2319 if ((hook == NULL)
2320 || NG_HOOK_NOT_VALID(hook)
2321 || NG_NODE_NOT_VALID(node) ) {
2322 error = EIO;
2323 NG_FREE_ITEM(item);
2324 break;
2325 }
2326 /*
2327 * If no receive method, just silently drop it.
2328 * Give preference to the hook over-ride method
2329 */
2330 if ((!(rcvdata = hook->hk_rcvdata))
2331 && (!(rcvdata = NG_HOOK_NODE(hook)->nd_type->rcvdata))) {
2332 error = 0;
2333 NG_FREE_ITEM(item);
2334 break;
2335 }
2336 error = (*rcvdata)(hook, item);
2337 break;
2338 case NGQF_MESG:
2339 if (hook) {
2340 if (NG_HOOK_NOT_VALID(hook)) {
2341 /*
2342 * The hook has been zapped then we can't
2343 * use it. Immediatly drop its reference.
2344 * The message may not need it.
2345 */
2346 NG_HOOK_UNREF(hook);
2347 hook = NULL;
2348 }
2349 }
2350 /*
2351 * Similarly, if the node is a zombie there is
2352 * nothing we can do with it, drop everything.
2353 */
2354 if (NG_NODE_NOT_VALID(node)) {
2355 TRAP_ERROR();
2356 error = EINVAL;
2357 NG_FREE_ITEM(item);
2358 } else {
2359 /*
2360 * Call the appropriate message handler for the object.
2361 * It is up to the message handler to free the message.
2362 * If it's a generic message, handle it generically,
2363 * otherwise call the type's message handler
2364 * (if it exists)
2365 * XXX (race). Remember that a queued message may
2366 * reference a node or hook that has just been
2367 * invalidated. It will exist as the queue code
2368 * is holding a reference, but..
2369 */
2370
2371 struct ng_mesg *msg = NGI_MSG(item);
2372
2373 /*
2374 * check if the generic handler owns it.
2375 */
2376 if ((msg->header.typecookie == NGM_GENERIC_COOKIE)
2377 && ((msg->header.flags & NGF_RESP) == 0)) {
2378 error = ng_generic_msg(node, item, hook);
2379 break;
2380 }
2381 /*
2382 * Now see if there is a handler (hook or node specific)
2383 * in the target node. If none, silently discard.
2384 */
2385 if (((!hook) || (!(rcvmsg = hook->hk_rcvmsg)))
2386 && (!(rcvmsg = node->nd_type->rcvmsg))) {
2387 TRAP_ERROR();
2388 error = 0;
2389 NG_FREE_ITEM(item);
2390 break;
2391 }
2392 error = (*rcvmsg)(node, item, hook);
2393 }
2394 break;
2395 case NGQF_FN:
2396 /*
2397 * We have to implicitly trust the hook,
2398 * as some of these are used for system purposes
2399 * where the hook is invalid. In the case of
2400 * the shutdown message we allow it to hit
2401 * even if the node is invalid.
2402 */
2403 if ((NG_NODE_NOT_VALID(node))
2404 && (NGI_FN(item) != &ng_rmnode)) {
2405 TRAP_ERROR();
2406 error = EINVAL;
2407 NG_FREE_ITEM(item);
2408 break;
2409 }
2410 (*NGI_FN(item))(node, hook, NGI_ARG1(item), NGI_ARG2(item));
2411 NG_FREE_ITEM(item);
2412 break;
2413
2414 }
2415 /*
2416 * We held references on some of the resources
2417 * that we took from the item. Now that we have
2418 * finished doing everything, drop those references.
2419 */
2420 if (hook) {
2421 NG_HOOK_UNREF(hook);
2422 }
2423
2424 if (was_reader) {
2425 ng_leave_read(&node->nd_input_queue);
2426 } else {
2427 ng_leave_write(&node->nd_input_queue);
2428 }
2429
2430 /* Apply callback. */
2431 if (apply != NULL)
2432 (*apply)(context, error);
2433
2434 return (error);
2435 }
2436
2437 /***********************************************************************
2438 * Implement the 'generic' control messages
2439 ***********************************************************************/
2440 static int
2441 ng_generic_msg(node_p here, item_p item, hook_p lasthook)
2442 {
2443 int error = 0;
2444 struct ng_mesg *msg;
2445 struct ng_mesg *resp = NULL;
2446
2447 NGI_GET_MSG(item, msg);
2448 if (msg->header.typecookie != NGM_GENERIC_COOKIE) {
2449 TRAP_ERROR();
2450 error = EINVAL;
2451 goto out;
2452 }
2453 switch (msg->header.cmd) {
2454 case NGM_SHUTDOWN:
2455 ng_rmnode(here, NULL, NULL, 0);
2456 break;
2457 case NGM_MKPEER:
2458 {
2459 struct ngm_mkpeer *const mkp = (struct ngm_mkpeer *) msg->data;
2460
2461 if (msg->header.arglen != sizeof(*mkp)) {
2462 TRAP_ERROR();
2463 error = EINVAL;
2464 break;
2465 }
2466 mkp->type[sizeof(mkp->type) - 1] = '\0';
2467 mkp->ourhook[sizeof(mkp->ourhook) - 1] = '\0';
2468 mkp->peerhook[sizeof(mkp->peerhook) - 1] = '\0';
2469 error = ng_mkpeer(here, mkp->ourhook, mkp->peerhook, mkp->type);
2470 break;
2471 }
2472 case NGM_CONNECT:
2473 {
2474 struct ngm_connect *const con =
2475 (struct ngm_connect *) msg->data;
2476 node_p node2;
2477
2478 if (msg->header.arglen != sizeof(*con)) {
2479 TRAP_ERROR();
2480 error = EINVAL;
2481 break;
2482 }
2483 con->path[sizeof(con->path) - 1] = '\0';
2484 con->ourhook[sizeof(con->ourhook) - 1] = '\0';
2485 con->peerhook[sizeof(con->peerhook) - 1] = '\0';
2486 /* Don't forget we get a reference.. */
2487 error = ng_path2noderef(here, con->path, &node2, NULL);
2488 if (error)
2489 break;
2490 error = ng_con_nodes(here, con->ourhook, node2, con->peerhook);
2491 NG_NODE_UNREF(node2);
2492 break;
2493 }
2494 case NGM_NAME:
2495 {
2496 struct ngm_name *const nam = (struct ngm_name *) msg->data;
2497
2498 if (msg->header.arglen != sizeof(*nam)) {
2499 TRAP_ERROR();
2500 error = EINVAL;
2501 break;
2502 }
2503 nam->name[sizeof(nam->name) - 1] = '\0';
2504 error = ng_name_node(here, nam->name);
2505 break;
2506 }
2507 case NGM_RMHOOK:
2508 {
2509 struct ngm_rmhook *const rmh = (struct ngm_rmhook *) msg->data;
2510 hook_p hook;
2511
2512 if (msg->header.arglen != sizeof(*rmh)) {
2513 TRAP_ERROR();
2514 error = EINVAL;
2515 break;
2516 }
2517 rmh->ourhook[sizeof(rmh->ourhook) - 1] = '\0';
2518 if ((hook = ng_findhook(here, rmh->ourhook)) != NULL)
2519 ng_destroy_hook(hook);
2520 break;
2521 }
2522 case NGM_NODEINFO:
2523 {
2524 struct nodeinfo *ni;
2525
2526 NG_MKRESPONSE(resp, msg, sizeof(*ni), M_NOWAIT);
2527 if (resp == NULL) {
2528 error = ENOMEM;
2529 break;
2530 }
2531
2532 /* Fill in node info */
2533 ni = (struct nodeinfo *) resp->data;
2534 if (NG_NODE_HAS_NAME(here))
2535 strcpy(ni->name, NG_NODE_NAME(here));
2536 strcpy(ni->type, here->nd_type->name);
2537 ni->id = ng_node2ID(here);
2538 ni->hooks = here->nd_numhooks;
2539 break;
2540 }
2541 case NGM_LISTHOOKS:
2542 {
2543 const int nhooks = here->nd_numhooks;
2544 struct hooklist *hl;
2545 struct nodeinfo *ni;
2546 hook_p hook;
2547
2548 /* Get response struct */
2549 NG_MKRESPONSE(resp, msg, sizeof(*hl)
2550 + (nhooks * sizeof(struct linkinfo)), M_NOWAIT);
2551 if (resp == NULL) {
2552 error = ENOMEM;
2553 break;
2554 }
2555 hl = (struct hooklist *) resp->data;
2556 ni = &hl->nodeinfo;
2557
2558 /* Fill in node info */
2559 if (NG_NODE_HAS_NAME(here))
2560 strcpy(ni->name, NG_NODE_NAME(here));
2561 strcpy(ni->type, here->nd_type->name);
2562 ni->id = ng_node2ID(here);
2563
2564 /* Cycle through the linked list of hooks */
2565 ni->hooks = 0;
2566 LIST_FOREACH(hook, &here->nd_hooks, hk_hooks) {
2567 struct linkinfo *const link = &hl->link[ni->hooks];
2568
2569 if (ni->hooks >= nhooks) {
2570 log(LOG_ERR, "%s: number of %s changed\n",
2571 __func__, "hooks");
2572 break;
2573 }
2574 if (NG_HOOK_NOT_VALID(hook))
2575 continue;
2576 strcpy(link->ourhook, NG_HOOK_NAME(hook));
2577 strcpy(link->peerhook, NG_PEER_HOOK_NAME(hook));
2578 if (NG_PEER_NODE_NAME(hook)[0] != '\0')
2579 strcpy(link->nodeinfo.name,
2580 NG_PEER_NODE_NAME(hook));
2581 strcpy(link->nodeinfo.type,
2582 NG_PEER_NODE(hook)->nd_type->name);
2583 link->nodeinfo.id = ng_node2ID(NG_PEER_NODE(hook));
2584 link->nodeinfo.hooks = NG_PEER_NODE(hook)->nd_numhooks;
2585 ni->hooks++;
2586 }
2587 break;
2588 }
2589
2590 case NGM_LISTNAMES:
2591 case NGM_LISTNODES:
2592 {
2593 const int unnamed = (msg->header.cmd == NGM_LISTNODES);
2594 struct namelist *nl;
2595 node_p node;
2596 int num = 0;
2597
2598 mtx_lock(&ng_nodelist_mtx);
2599 /* Count number of nodes */
2600 LIST_FOREACH(node, &ng_nodelist, nd_nodes) {
2601 if (NG_NODE_IS_VALID(node)
2602 && (unnamed || NG_NODE_HAS_NAME(node))) {
2603 num++;
2604 }
2605 }
2606 mtx_unlock(&ng_nodelist_mtx);
2607
2608 /* Get response struct */
2609 NG_MKRESPONSE(resp, msg, sizeof(*nl)
2610 + (num * sizeof(struct nodeinfo)), M_NOWAIT);
2611 if (resp == NULL) {
2612 error = ENOMEM;
2613 break;
2614 }
2615 nl = (struct namelist *) resp->data;
2616
2617 /* Cycle through the linked list of nodes */
2618 nl->numnames = 0;
2619 mtx_lock(&ng_nodelist_mtx);
2620 LIST_FOREACH(node, &ng_nodelist, nd_nodes) {
2621 struct nodeinfo *const np = &nl->nodeinfo[nl->numnames];
2622
2623 if (nl->numnames >= num) {
2624 log(LOG_ERR, "%s: number of %s changed\n",
2625 __func__, "nodes");
2626 break;
2627 }
2628 if (NG_NODE_NOT_VALID(node))
2629 continue;
2630 if (!unnamed && (! NG_NODE_HAS_NAME(node)))
2631 continue;
2632 if (NG_NODE_HAS_NAME(node))
2633 strcpy(np->name, NG_NODE_NAME(node));
2634 strcpy(np->type, node->nd_type->name);
2635 np->id = ng_node2ID(node);
2636 np->hooks = node->nd_numhooks;
2637 nl->numnames++;
2638 }
2639 mtx_unlock(&ng_nodelist_mtx);
2640 break;
2641 }
2642
2643 case NGM_LISTTYPES:
2644 {
2645 struct typelist *tl;
2646 struct ng_type *type;
2647 int num = 0;
2648
2649 mtx_lock(&ng_typelist_mtx);
2650 /* Count number of types */
2651 LIST_FOREACH(type, &ng_typelist, types) {
2652 num++;
2653 }
2654 mtx_unlock(&ng_typelist_mtx);
2655
2656 /* Get response struct */
2657 NG_MKRESPONSE(resp, msg, sizeof(*tl)
2658 + (num * sizeof(struct typeinfo)), M_NOWAIT);
2659 if (resp == NULL) {
2660 error = ENOMEM;
2661 break;
2662 }
2663 tl = (struct typelist *) resp->data;
2664
2665 /* Cycle through the linked list of types */
2666 tl->numtypes = 0;
2667 mtx_lock(&ng_typelist_mtx);
2668 LIST_FOREACH(type, &ng_typelist, types) {
2669 struct typeinfo *const tp = &tl->typeinfo[tl->numtypes];
2670
2671 if (tl->numtypes >= num) {
2672 log(LOG_ERR, "%s: number of %s changed\n",
2673 __func__, "types");
2674 break;
2675 }
2676 strcpy(tp->type_name, type->name);
2677 tp->numnodes = type->refs - 1; /* don't count list */
2678 tl->numtypes++;
2679 }
2680 mtx_unlock(&ng_typelist_mtx);
2681 break;
2682 }
2683
2684 case NGM_BINARY2ASCII:
2685 {
2686 int bufSize = 20 * 1024; /* XXX hard coded constant */
2687 const struct ng_parse_type *argstype;
2688 const struct ng_cmdlist *c;
2689 struct ng_mesg *binary, *ascii;
2690
2691 /* Data area must contain a valid netgraph message */
2692 binary = (struct ng_mesg *)msg->data;
2693 if (msg->header.arglen < sizeof(struct ng_mesg)
2694 || (msg->header.arglen - sizeof(struct ng_mesg)
2695 < binary->header.arglen)) {
2696 TRAP_ERROR();
2697 error = EINVAL;
2698 break;
2699 }
2700
2701 /* Get a response message with lots of room */
2702 NG_MKRESPONSE(resp, msg, sizeof(*ascii) + bufSize, M_NOWAIT);
2703 if (resp == NULL) {
2704 error = ENOMEM;
2705 break;
2706 }
2707 ascii = (struct ng_mesg *)resp->data;
2708
2709 /* Copy binary message header to response message payload */
2710 bcopy(binary, ascii, sizeof(*binary));
2711
2712 /* Find command by matching typecookie and command number */
2713 for (c = here->nd_type->cmdlist;
2714 c != NULL && c->name != NULL; c++) {
2715 if (binary->header.typecookie == c->cookie
2716 && binary->header.cmd == c->cmd)
2717 break;
2718 }
2719 if (c == NULL || c->name == NULL) {
2720 for (c = ng_generic_cmds; c->name != NULL; c++) {
2721 if (binary->header.typecookie == c->cookie
2722 && binary->header.cmd == c->cmd)
2723 break;
2724 }
2725 if (c->name == NULL) {
2726 NG_FREE_MSG(resp);
2727 error = ENOSYS;
2728 break;
2729 }
2730 }
2731
2732 /* Convert command name to ASCII */
2733 snprintf(ascii->header.cmdstr, sizeof(ascii->header.cmdstr),
2734 "%s", c->name);
2735
2736 /* Convert command arguments to ASCII */
2737 argstype = (binary->header.flags & NGF_RESP) ?
2738 c->respType : c->mesgType;
2739 if (argstype == NULL) {
2740 *ascii->data = '\0';
2741 } else {
2742 if ((error = ng_unparse(argstype,
2743 (u_char *)binary->data,
2744 ascii->data, bufSize)) != 0) {
2745 NG_FREE_MSG(resp);
2746 break;
2747 }
2748 }
2749
2750 /* Return the result as struct ng_mesg plus ASCII string */
2751 bufSize = strlen(ascii->data) + 1;
2752 ascii->header.arglen = bufSize;
2753 resp->header.arglen = sizeof(*ascii) + bufSize;
2754 break;
2755 }
2756
2757 case NGM_ASCII2BINARY:
2758 {
2759 int bufSize = 2000; /* XXX hard coded constant */
2760 const struct ng_cmdlist *c;
2761 const struct ng_parse_type *argstype;
2762 struct ng_mesg *ascii, *binary;
2763 int off = 0;
2764
2765 /* Data area must contain at least a struct ng_mesg + '\0' */
2766 ascii = (struct ng_mesg *)msg->data;
2767 if ((msg->header.arglen < sizeof(*ascii) + 1)
2768 || (ascii->header.arglen < 1)
2769 || (msg->header.arglen
2770 < sizeof(*ascii) + ascii->header.arglen)) {
2771 TRAP_ERROR();
2772 error = EINVAL;
2773 break;
2774 }
2775 ascii->data[ascii->header.arglen - 1] = '\0';
2776
2777 /* Get a response message with lots of room */
2778 NG_MKRESPONSE(resp, msg, sizeof(*binary) + bufSize, M_NOWAIT);
2779 if (resp == NULL) {
2780 error = ENOMEM;
2781 break;
2782 }
2783 binary = (struct ng_mesg *)resp->data;
2784
2785 /* Copy ASCII message header to response message payload */
2786 bcopy(ascii, binary, sizeof(*ascii));
2787
2788 /* Find command by matching ASCII command string */
2789 for (c = here->nd_type->cmdlist;
2790 c != NULL && c->name != NULL; c++) {
2791 if (strcmp(ascii->header.cmdstr, c->name) == 0)
2792 break;
2793 }
2794 if (c == NULL || c->name == NULL) {
2795 for (c = ng_generic_cmds; c->name != NULL; c++) {
2796 if (strcmp(ascii->header.cmdstr, c->name) == 0)
2797 break;
2798 }
2799 if (c->name == NULL) {
2800 NG_FREE_MSG(resp);
2801 error = ENOSYS;
2802 break;
2803 }
2804 }
2805
2806 /* Convert command name to binary */
2807 binary->header.cmd = c->cmd;
2808 binary->header.typecookie = c->cookie;
2809
2810 /* Convert command arguments to binary */
2811 argstype = (binary->header.flags & NGF_RESP) ?
2812 c->respType : c->mesgType;
2813 if (argstype == NULL) {
2814 bufSize = 0;
2815 } else {
2816 if ((error = ng_parse(argstype, ascii->data,
2817 &off, (u_char *)binary->data, &bufSize)) != 0) {
2818 NG_FREE_MSG(resp);
2819 break;
2820 }
2821 }
2822
2823 /* Return the result */
2824 binary->header.arglen = bufSize;
2825 resp->header.arglen = sizeof(*binary) + bufSize;
2826 break;
2827 }
2828
2829 case NGM_TEXT_CONFIG:
2830 case NGM_TEXT_STATUS:
2831 /*
2832 * This one is tricky as it passes the command down to the
2833 * actual node, even though it is a generic type command.
2834 * This means we must assume that the item/msg is already freed
2835 * when control passes back to us.
2836 */
2837 if (here->nd_type->rcvmsg != NULL) {
2838 NGI_MSG(item) = msg; /* put it back as we found it */
2839 return((*here->nd_type->rcvmsg)(here, item, lasthook));
2840 }
2841 /* Fall through if rcvmsg not supported */
2842 default:
2843 TRAP_ERROR();
2844 error = EINVAL;
2845 }
2846 /*
2847 * Sometimes a generic message may be statically allocated
2848 * to avoid problems with allocating when in tight memeory situations.
2849 * Don't free it if it is so.
2850 * I break them appart here, because erros may cause a free if the item
2851 * in which case we'd be doing it twice.
2852 * they are kept together above, to simplify freeing.
2853 */
2854 out:
2855 NG_RESPOND_MSG(error, here, item, resp);
2856 if (msg)
2857 NG_FREE_MSG(msg);
2858 return (error);
2859 }
2860
2861 /************************************************************************
2862 Queue element get/free routines
2863 ************************************************************************/
2864
2865 uma_zone_t ng_qzone;
2866 static int maxalloc = 512; /* limit the damage of a leak */
2867
2868 TUNABLE_INT("net.graph.maxalloc", &maxalloc);
2869 SYSCTL_INT(_net_graph, OID_AUTO, maxalloc, CTLFLAG_RDTUN, &maxalloc,
2870 0, "Maximum number of queue items to allocate");
2871
2872 #ifdef NETGRAPH_DEBUG
2873 static TAILQ_HEAD(, ng_item) ng_itemlist = TAILQ_HEAD_INITIALIZER(ng_itemlist);
2874 static int allocated; /* number of items malloc'd */
2875 #endif
2876
2877 /*
2878 * Get a queue entry.
2879 * This is usually called when a packet first enters netgraph.
2880 * By definition, this is usually from an interrupt, or from a user.
2881 * Users are not so important, but try be quick for the times that it's
2882 * an interrupt.
2883 */
2884 static __inline item_p
2885 ng_getqblk(int flags)
2886 {
2887 item_p item = NULL;
2888 int wait;
2889
2890 wait = (flags & NG_WAITOK) ? M_WAITOK : M_NOWAIT;
2891
2892 item = uma_zalloc(ng_qzone, wait | M_ZERO);
2893
2894 #ifdef NETGRAPH_DEBUG
2895 if (item) {
2896 mtx_lock(&ngq_mtx);
2897 TAILQ_INSERT_TAIL(&ng_itemlist, item, all);
2898 allocated++;
2899 mtx_unlock(&ngq_mtx);
2900 }
2901 #endif
2902
2903 return (item);
2904 }
2905
2906 /*
2907 * Release a queue entry
2908 */
2909 void
2910 ng_free_item(item_p item)
2911 {
2912 /*
2913 * The item may hold resources on it's own. We need to free
2914 * these before we can free the item. What they are depends upon
2915 * what kind of item it is. it is important that nodes zero
2916 * out pointers to resources that they remove from the item
2917 * or we release them again here.
2918 */
2919 switch (item->el_flags & NGQF_TYPE) {
2920 case NGQF_DATA:
2921 /* If we have an mbuf still attached.. */
2922 NG_FREE_M(_NGI_M(item));
2923 break;
2924 case NGQF_MESG:
2925 _NGI_RETADDR(item) = 0;
2926 NG_FREE_MSG(_NGI_MSG(item));
2927 break;
2928 case NGQF_FN:
2929 /* nothing to free really, */
2930 _NGI_FN(item) = NULL;
2931 _NGI_ARG1(item) = NULL;
2932 _NGI_ARG2(item) = 0;
2933 case NGQF_UNDEF:
2934 break;
2935 }
2936 /* If we still have a node or hook referenced... */
2937 _NGI_CLR_NODE(item);
2938 _NGI_CLR_HOOK(item);
2939
2940 #ifdef NETGRAPH_DEBUG
2941 mtx_lock(&ngq_mtx);
2942 TAILQ_REMOVE(&ng_itemlist, item, all);
2943 allocated--;
2944 mtx_unlock(&ngq_mtx);
2945 #endif
2946 uma_zfree(ng_qzone, item);
2947 }
2948
2949 /************************************************************************
2950 Module routines
2951 ************************************************************************/
2952
2953 /*
2954 * Handle the loading/unloading of a netgraph node type module
2955 */
2956 int
2957 ng_mod_event(module_t mod, int event, void *data)
2958 {
2959 struct ng_type *const type = data;
2960 int s, error = 0;
2961
2962 switch (event) {
2963 case MOD_LOAD:
2964
2965 /* Register new netgraph node type */
2966 s = splnet();
2967 if ((error = ng_newtype(type)) != 0) {
2968 splx(s);
2969 break;
2970 }
2971
2972 /* Call type specific code */
2973 if (type->mod_event != NULL)
2974 if ((error = (*type->mod_event)(mod, event, data))) {
2975 mtx_lock(&ng_typelist_mtx);
2976 type->refs--; /* undo it */
2977 LIST_REMOVE(type, types);
2978 mtx_unlock(&ng_typelist_mtx);
2979 }
2980 splx(s);
2981 break;
2982
2983 case MOD_UNLOAD:
2984 s = splnet();
2985 if (type->refs > 1) { /* make sure no nodes exist! */
2986 error = EBUSY;
2987 } else {
2988 if (type->refs == 0) {
2989 /* failed load, nothing to undo */
2990 splx(s);
2991 break;
2992 }
2993 if (type->mod_event != NULL) { /* check with type */
2994 error = (*type->mod_event)(mod, event, data);
2995 if (error != 0) { /* type refuses.. */
2996 splx(s);
2997 break;
2998 }
2999 }
3000 mtx_lock(&ng_typelist_mtx);
3001 LIST_REMOVE(type, types);
3002 mtx_unlock(&ng_typelist_mtx);
3003 }
3004 splx(s);
3005 break;
3006
3007 default:
3008 if (type->mod_event != NULL)
3009 error = (*type->mod_event)(mod, event, data);
3010 else
3011 error = EOPNOTSUPP; /* XXX ? */
3012 break;
3013 }
3014 return (error);
3015 }
3016
3017 /*
3018 * Handle loading and unloading for this code.
3019 * The only thing we need to link into is the NETISR strucure.
3020 */
3021 static int
3022 ngb_mod_event(module_t mod, int event, void *data)
3023 {
3024 int error = 0;
3025
3026 switch (event) {
3027 case MOD_LOAD:
3028 /* Initialize everything. */
3029 mtx_init(&ng_worklist_mtx, "ng_worklist", NULL, MTX_SPIN);
3030 mtx_init(&ng_typelist_mtx, "netgraph types mutex", NULL,
3031 MTX_DEF);
3032 mtx_init(&ng_nodelist_mtx, "netgraph nodelist mutex", NULL,
3033 MTX_DEF);
3034 mtx_init(&ng_idhash_mtx, "netgraph idhash mutex", NULL,
3035 MTX_DEF);
3036 #ifdef NETGRAPH_DEBUG
3037 mtx_init(&ngq_mtx, "netgraph item list mutex", NULL,
3038 MTX_DEF);
3039 #endif
3040 ng_qzone = uma_zcreate("NetGraph items", sizeof(struct ng_item),
3041 NULL, NULL, NULL, NULL, UMA_ALIGN_CACHE, 0);
3042 uma_zone_set_max(ng_qzone, maxalloc);
3043 netisr_register(NETISR_NETGRAPH, (netisr_t *)ngintr, NULL,
3044 NETISR_MPSAFE);
3045 break;
3046 case MOD_UNLOAD:
3047 /* You cant unload it because an interface may be using it. */
3048 error = EBUSY;
3049 break;
3050 default:
3051 error = EOPNOTSUPP;
3052 break;
3053 }
3054 return (error);
3055 }
3056
3057 static moduledata_t netgraph_mod = {
3058 "netgraph",
3059 ngb_mod_event,
3060 (NULL)
3061 };
3062 DECLARE_MODULE(netgraph, netgraph_mod, SI_SUB_NETGRAPH, SI_ORDER_MIDDLE);
3063 SYSCTL_NODE(_net, OID_AUTO, graph, CTLFLAG_RW, 0, "netgraph Family");
3064 SYSCTL_INT(_net_graph, OID_AUTO, abi_version, CTLFLAG_RD, 0, NG_ABI_VERSION,"");
3065 SYSCTL_INT(_net_graph, OID_AUTO, msg_version, CTLFLAG_RD, 0, NG_VERSION, "");
3066
3067 #ifdef NETGRAPH_DEBUG
3068 void
3069 dumphook (hook_p hook, char *file, int line)
3070 {
3071 printf("hook: name %s, %d refs, Last touched:\n",
3072 _NG_HOOK_NAME(hook), hook->hk_refs);
3073 printf(" Last active @ %s, line %d\n",
3074 hook->lastfile, hook->lastline);
3075 if (line) {
3076 printf(" problem discovered at file %s, line %d\n", file, line);
3077 }
3078 }
3079
3080 void
3081 dumpnode(node_p node, char *file, int line)
3082 {
3083 printf("node: ID [%x]: type '%s', %d hooks, flags 0x%x, %d refs, %s:\n",
3084 _NG_NODE_ID(node), node->nd_type->name,
3085 node->nd_numhooks, node->nd_flags,
3086 node->nd_refs, node->nd_name);
3087 printf(" Last active @ %s, line %d\n",
3088 node->lastfile, node->lastline);
3089 if (line) {
3090 printf(" problem discovered at file %s, line %d\n", file, line);
3091 }
3092 }
3093
3094 void
3095 dumpitem(item_p item, char *file, int line)
3096 {
3097 printf(" ACTIVE item, last used at %s, line %d",
3098 item->lastfile, item->lastline);
3099 switch(item->el_flags & NGQF_TYPE) {
3100 case NGQF_DATA:
3101 printf(" - [data]\n");
3102 break;
3103 case NGQF_MESG:
3104 printf(" - retaddr[%d]:\n", _NGI_RETADDR(item));
3105 break;
3106 case NGQF_FN:
3107 printf(" - fn@%p (%p, %p, %p, %d (%x))\n",
3108 item->body.fn.fn_fn,
3109 _NGI_NODE(item),
3110 _NGI_HOOK(item),
3111 item->body.fn.fn_arg1,
3112 item->body.fn.fn_arg2,
3113 item->body.fn.fn_arg2);
3114 break;
3115 case NGQF_UNDEF:
3116 printf(" - UNDEFINED!\n");
3117 }
3118 if (line) {
3119 printf(" problem discovered at file %s, line %d\n", file, line);
3120 if (_NGI_NODE(item)) {
3121 printf("node %p ([%x])\n",
3122 _NGI_NODE(item), ng_node2ID(_NGI_NODE(item)));
3123 }
3124 }
3125 }
3126
3127 static void
3128 ng_dumpitems(void)
3129 {
3130 item_p item;
3131 int i = 1;
3132 TAILQ_FOREACH(item, &ng_itemlist, all) {
3133 printf("[%d] ", i++);
3134 dumpitem(item, NULL, 0);
3135 }
3136 }
3137
3138 static void
3139 ng_dumpnodes(void)
3140 {
3141 node_p node;
3142 int i = 1;
3143 mtx_lock(&ng_nodelist_mtx);
3144 SLIST_FOREACH(node, &ng_allnodes, nd_all) {
3145 printf("[%d] ", i++);
3146 dumpnode(node, NULL, 0);
3147 }
3148 mtx_unlock(&ng_nodelist_mtx);
3149 }
3150
3151 static void
3152 ng_dumphooks(void)
3153 {
3154 hook_p hook;
3155 int i = 1;
3156 mtx_lock(&ng_nodelist_mtx);
3157 SLIST_FOREACH(hook, &ng_allhooks, hk_all) {
3158 printf("[%d] ", i++);
3159 dumphook(hook, NULL, 0);
3160 }
3161 mtx_unlock(&ng_nodelist_mtx);
3162 }
3163
3164 static int
3165 sysctl_debug_ng_dump_items(SYSCTL_HANDLER_ARGS)
3166 {
3167 int error;
3168 int val;
3169 int i;
3170
3171 val = allocated;
3172 i = 1;
3173 error = sysctl_handle_int(oidp, &val, sizeof(int), req);
3174 if (error != 0 || req->newptr == NULL)
3175 return (error);
3176 if (val == 42) {
3177 ng_dumpitems();
3178 ng_dumpnodes();
3179 ng_dumphooks();
3180 }
3181 return (0);
3182 }
3183
3184 SYSCTL_PROC(_debug, OID_AUTO, ng_dump_items, CTLTYPE_INT | CTLFLAG_RW,
3185 0, sizeof(int), sysctl_debug_ng_dump_items, "I", "Number of allocated items");
3186 #endif /* NETGRAPH_DEBUG */
3187
3188
3189 /***********************************************************************
3190 * Worklist routines
3191 **********************************************************************/
3192 /* NETISR thread enters here */
3193 /*
3194 * Pick a node off the list of nodes with work,
3195 * try get an item to process off it.
3196 * If there are no more, remove the node from the list.
3197 */
3198 static void
3199 ngintr(void)
3200 {
3201 item_p item;
3202 node_p node = NULL;
3203
3204 for (;;) {
3205 mtx_lock_spin(&ng_worklist_mtx);
3206 node = TAILQ_FIRST(&ng_worklist);
3207 if (!node) {
3208 mtx_unlock_spin(&ng_worklist_mtx);
3209 break;
3210 }
3211 node->nd_flags &= ~NGF_WORKQ;
3212 TAILQ_REMOVE(&ng_worklist, node, nd_work);
3213 mtx_unlock_spin(&ng_worklist_mtx);
3214 /*
3215 * We have the node. We also take over the reference
3216 * that the list had on it.
3217 * Now process as much as you can, until it won't
3218 * let you have another item off the queue.
3219 * All this time, keep the reference
3220 * that lets us be sure that the node still exists.
3221 * Let the reference go at the last minute.
3222 * ng_dequeue will put us back on the worklist
3223 * if there is more too do. This may be of use if there
3224 * are Multiple Processors and multiple Net threads in the
3225 * future.
3226 */
3227 for (;;) {
3228 mtx_lock_spin(&node->nd_input_queue.q_mtx);
3229 item = ng_dequeue(&node->nd_input_queue);
3230 if (item == NULL) {
3231 mtx_unlock_spin(&node->nd_input_queue.q_mtx);
3232 break; /* go look for another node */
3233 } else {
3234 mtx_unlock_spin(&node->nd_input_queue.q_mtx);
3235 NGI_GET_NODE(item, node); /* zaps stored node */
3236 ng_apply_item(node, item);
3237 NG_NODE_UNREF(node);
3238 }
3239 }
3240 NG_NODE_UNREF(node);
3241 }
3242 }
3243
3244 static void
3245 ng_worklist_remove(node_p node)
3246 {
3247 mtx_lock_spin(&ng_worklist_mtx);
3248 if (node->nd_flags & NGF_WORKQ) {
3249 node->nd_flags &= ~NGF_WORKQ;
3250 TAILQ_REMOVE(&ng_worklist, node, nd_work);
3251 mtx_unlock_spin(&ng_worklist_mtx);
3252 NG_NODE_UNREF(node);
3253 } else {
3254 mtx_unlock_spin(&ng_worklist_mtx);
3255 }
3256 }
3257
3258 /*
3259 * XXX
3260 * It's posible that a debugging NG_NODE_REF may need
3261 * to be outside the mutex zone
3262 */
3263 static void
3264 ng_setisr(node_p node)
3265 {
3266
3267 mtx_assert(&node->nd_input_queue.q_mtx, MA_OWNED);
3268
3269 if ((node->nd_flags & NGF_WORKQ) == 0) {
3270 /*
3271 * If we are not already on the work queue,
3272 * then put us on.
3273 */
3274 node->nd_flags |= NGF_WORKQ;
3275 mtx_lock_spin(&ng_worklist_mtx);
3276 TAILQ_INSERT_TAIL(&ng_worklist, node, nd_work);
3277 mtx_unlock_spin(&ng_worklist_mtx);
3278 NG_NODE_REF(node); /* XXX fafe in mutex? */
3279 }
3280 schednetisr(NETISR_NETGRAPH);
3281 }
3282
3283
3284 /***********************************************************************
3285 * Externally useable functions to set up a queue item ready for sending
3286 ***********************************************************************/
3287
3288 #ifdef NETGRAPH_DEBUG
3289 #define ITEM_DEBUG_CHECKS \
3290 do { \
3291 if (NGI_NODE(item) ) { \
3292 printf("item already has node"); \
3293 kdb_enter("has node"); \
3294 NGI_CLR_NODE(item); \
3295 } \
3296 if (NGI_HOOK(item) ) { \
3297 printf("item already has hook"); \
3298 kdb_enter("has hook"); \
3299 NGI_CLR_HOOK(item); \
3300 } \
3301 } while (0)
3302 #else
3303 #define ITEM_DEBUG_CHECKS
3304 #endif
3305
3306 /*
3307 * Put mbuf into the item.
3308 * Hook and node references will be removed when the item is dequeued.
3309 * (or equivalent)
3310 * (XXX) Unsafe because no reference held by peer on remote node.
3311 * remote node might go away in this timescale.
3312 * We know the hooks can't go away because that would require getting
3313 * a writer item on both nodes and we must have at least a reader
3314 * here to eb able to do this.
3315 * Note that the hook loaded is the REMOTE hook.
3316 *
3317 * This is possibly in the critical path for new data.
3318 */
3319 item_p
3320 ng_package_data(struct mbuf *m, int flags)
3321 {
3322 item_p item;
3323
3324 if ((item = ng_getqblk(flags)) == NULL) {
3325 NG_FREE_M(m);
3326 return (NULL);
3327 }
3328 ITEM_DEBUG_CHECKS;
3329 item->el_flags = NGQF_DATA;
3330 item->el_next = NULL;
3331 NGI_M(item) = m;
3332 return (item);
3333 }
3334
3335 /*
3336 * Allocate a queue item and put items into it..
3337 * Evaluate the address as this will be needed to queue it and
3338 * to work out what some of the fields should be.
3339 * Hook and node references will be removed when the item is dequeued.
3340 * (or equivalent)
3341 */
3342 item_p
3343 ng_package_msg(struct ng_mesg *msg, int flags)
3344 {
3345 item_p item;
3346
3347 if ((item = ng_getqblk(flags)) == NULL) {
3348 NG_FREE_MSG(msg);
3349 return (NULL);
3350 }
3351 ITEM_DEBUG_CHECKS;
3352 item->el_flags = NGQF_MESG;
3353 item->el_next = NULL;
3354 /*
3355 * Set the current lasthook into the queue item
3356 */
3357 NGI_MSG(item) = msg;
3358 NGI_RETADDR(item) = 0;
3359 return (item);
3360 }
3361
3362
3363
3364 #define SET_RETADDR(item, here, retaddr) \
3365 do { /* Data or fn items don't have retaddrs */ \
3366 if ((item->el_flags & NGQF_TYPE) == NGQF_MESG) { \
3367 if (retaddr) { \
3368 NGI_RETADDR(item) = retaddr; \
3369 } else { \
3370 /* \
3371 * The old return address should be ok. \
3372 * If there isn't one, use the address \
3373 * here. \
3374 */ \
3375 if (NGI_RETADDR(item) == 0) { \
3376 NGI_RETADDR(item) \
3377 = ng_node2ID(here); \
3378 } \
3379 } \
3380 } \
3381 } while (0)
3382
3383 int
3384 ng_address_hook(node_p here, item_p item, hook_p hook, ng_ID_t retaddr)
3385 {
3386 hook_p peer;
3387 node_p peernode;
3388 ITEM_DEBUG_CHECKS;
3389 /*
3390 * Quick sanity check..
3391 * Since a hook holds a reference on it's node, once we know
3392 * that the peer is still connected (even if invalid,) we know
3393 * that the peer node is present, though maybe invalid.
3394 */
3395 if ((hook == NULL)
3396 || NG_HOOK_NOT_VALID(hook)
3397 || (NG_HOOK_PEER(hook) == NULL)
3398 || NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook))
3399 || NG_NODE_NOT_VALID(NG_PEER_NODE(hook))) {
3400 NG_FREE_ITEM(item);
3401 TRAP_ERROR();
3402 return (ENETDOWN);
3403 }
3404
3405 /*
3406 * Transfer our interest to the other (peer) end.
3407 */
3408 peer = NG_HOOK_PEER(hook);
3409 NG_HOOK_REF(peer);
3410 NGI_SET_HOOK(item, peer);
3411 peernode = NG_PEER_NODE(hook);
3412 NG_NODE_REF(peernode);
3413 NGI_SET_NODE(item, peernode);
3414 SET_RETADDR(item, here, retaddr);
3415 return (0);
3416 }
3417
3418 int
3419 ng_address_path(node_p here, item_p item, char *address, ng_ID_t retaddr)
3420 {
3421 node_p dest = NULL;
3422 hook_p hook = NULL;
3423 int error;
3424
3425 ITEM_DEBUG_CHECKS;
3426 /*
3427 * Note that ng_path2noderef increments the reference count
3428 * on the node for us if it finds one. So we don't have to.
3429 */
3430 error = ng_path2noderef(here, address, &dest, &hook);
3431 if (error) {
3432 NG_FREE_ITEM(item);
3433 return (error);
3434 }
3435 NGI_SET_NODE(item, dest);
3436 if ( hook) {
3437 NG_HOOK_REF(hook); /* don't let it go while on the queue */
3438 NGI_SET_HOOK(item, hook);
3439 }
3440 SET_RETADDR(item, here, retaddr);
3441 return (0);
3442 }
3443
3444 int
3445 ng_address_ID(node_p here, item_p item, ng_ID_t ID, ng_ID_t retaddr)
3446 {
3447 node_p dest;
3448
3449 ITEM_DEBUG_CHECKS;
3450 /*
3451 * Find the target node.
3452 */
3453 dest = ng_ID2noderef(ID); /* GETS REFERENCE! */
3454 if (dest == NULL) {
3455 NG_FREE_ITEM(item);
3456 TRAP_ERROR();
3457 return(EINVAL);
3458 }
3459 /* Fill out the contents */
3460 item->el_flags = NGQF_MESG;
3461 item->el_next = NULL;
3462 NGI_SET_NODE(item, dest);
3463 NGI_CLR_HOOK(item);
3464 SET_RETADDR(item, here, retaddr);
3465 return (0);
3466 }
3467
3468 /*
3469 * special case to send a message to self (e.g. destroy node)
3470 * Possibly indicate an arrival hook too.
3471 * Useful for removing that hook :-)
3472 */
3473 item_p
3474 ng_package_msg_self(node_p here, hook_p hook, struct ng_mesg *msg)
3475 {
3476 item_p item;
3477
3478 /*
3479 * Find the target node.
3480 * If there is a HOOK argument, then use that in preference
3481 * to the address.
3482 */
3483 if ((item = ng_getqblk(NG_NOFLAGS)) == NULL) {
3484 NG_FREE_MSG(msg);
3485 return (NULL);
3486 }
3487
3488 /* Fill out the contents */
3489 item->el_flags = NGQF_MESG;
3490 item->el_next = NULL;
3491 NG_NODE_REF(here);
3492 NGI_SET_NODE(item, here);
3493 if (hook) {
3494 NG_HOOK_REF(hook);
3495 NGI_SET_HOOK(item, hook);
3496 }
3497 NGI_MSG(item) = msg;
3498 NGI_RETADDR(item) = ng_node2ID(here);
3499 return (item);
3500 }
3501
3502 int
3503 ng_send_fn1(node_p node, hook_p hook, ng_item_fn *fn, void * arg1, int arg2,
3504 int flags)
3505 {
3506 item_p item;
3507
3508 if ((item = ng_getqblk(flags)) == NULL) {
3509 return (ENOMEM);
3510 }
3511 item->el_flags = NGQF_FN | NGQF_WRITER;
3512 NG_NODE_REF(node); /* and one for the item */
3513 NGI_SET_NODE(item, node);
3514 if (hook) {
3515 NG_HOOK_REF(hook);
3516 NGI_SET_HOOK(item, hook);
3517 }
3518 NGI_FN(item) = fn;
3519 NGI_ARG1(item) = arg1;
3520 NGI_ARG2(item) = arg2;
3521 return(ng_snd_item(item, flags));
3522 }
3523
3524 /*
3525 * Official timeout routines for Netgraph nodes.
3526 */
3527 static void
3528 ng_callout_trampoline(void *arg)
3529 {
3530 item_p item = arg;
3531
3532 ng_snd_item(item, 0);
3533 }
3534
3535
3536 int
3537 ng_callout(struct callout *c, node_p node, hook_p hook, int ticks,
3538 ng_item_fn *fn, void * arg1, int arg2)
3539 {
3540 item_p item, oitem;
3541
3542 if ((item = ng_getqblk(NG_NOFLAGS)) == NULL)
3543 return (ENOMEM);
3544
3545 item->el_flags = NGQF_FN | NGQF_WRITER;
3546 NG_NODE_REF(node); /* and one for the item */
3547 NGI_SET_NODE(item, node);
3548 if (hook) {
3549 NG_HOOK_REF(hook);
3550 NGI_SET_HOOK(item, hook);
3551 }
3552 NGI_FN(item) = fn;
3553 NGI_ARG1(item) = arg1;
3554 NGI_ARG2(item) = arg2;
3555 oitem = c->c_arg;
3556 if (callout_reset(c, ticks, &ng_callout_trampoline, item) == 1 &&
3557 oitem != NULL)
3558 NG_FREE_ITEM(oitem);
3559 return (0);
3560 }
3561
3562 /* A special modified version of untimeout() */
3563 int
3564 ng_uncallout(struct callout *c, node_p node)
3565 {
3566 item_p item;
3567 int rval;
3568
3569 if (c == NULL)
3570 return (0);
3571 rval = callout_stop(c);
3572 item = c->c_arg;
3573 /* Do an extra check */
3574 if ((rval > 0) && (c->c_func == &ng_callout_trampoline) &&
3575 (NGI_NODE(item) == node)) {
3576 /*
3577 * We successfully removed it from the queue before it ran
3578 * So now we need to unreference everything that was
3579 * given extra references. (NG_FREE_ITEM does this).
3580 */
3581 NG_FREE_ITEM(item);
3582 }
3583 c->c_arg = NULL;
3584
3585 return (rval);
3586 }
3587
3588 /*
3589 * Set the address, if none given, give the node here.
3590 */
3591 void
3592 ng_replace_retaddr(node_p here, item_p item, ng_ID_t retaddr)
3593 {
3594 if (retaddr) {
3595 NGI_RETADDR(item) = retaddr;
3596 } else {
3597 /*
3598 * The old return address should be ok.
3599 * If there isn't one, use the address here.
3600 */
3601 NGI_RETADDR(item) = ng_node2ID(here);
3602 }
3603 }
3604
3605 #define TESTING
3606 #ifdef TESTING
3607 /* just test all the macros */
3608 void
3609 ng_macro_test(item_p item);
3610 void
3611 ng_macro_test(item_p item)
3612 {
3613 node_p node = NULL;
3614 hook_p hook = NULL;
3615 struct mbuf *m;
3616 struct ng_mesg *msg;
3617 ng_ID_t retaddr;
3618 int error;
3619
3620 NGI_GET_M(item, m);
3621 NGI_GET_MSG(item, msg);
3622 retaddr = NGI_RETADDR(item);
3623 NG_SEND_DATA(error, hook, m, NULL);
3624 NG_SEND_DATA_ONLY(error, hook, m);
3625 NG_FWD_NEW_DATA(error, item, hook, m);
3626 NG_FWD_ITEM_HOOK(error, item, hook);
3627 NG_SEND_MSG_HOOK(error, node, msg, hook, retaddr);
3628 NG_SEND_MSG_ID(error, node, msg, retaddr, retaddr);
3629 NG_SEND_MSG_PATH(error, node, msg, ".:", retaddr);
3630 NG_FWD_MSG_HOOK(error, node, item, hook, retaddr);
3631 }
3632 #endif /* TESTING */
3633
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