1 /*
2 * ng_base.c
3 */
4
5 /*-
6 * Copyright (c) 1996-1999 Whistle Communications, Inc.
7 * All rights reserved.
8 *
9 * Subject to the following obligations and disclaimer of warranty, use and
10 * redistribution of this software, in source or object code forms, with or
11 * without modifications are expressly permitted by Whistle Communications;
12 * provided, however, that:
13 * 1. Any and all reproductions of the source or object code must include the
14 * copyright notice above and the following disclaimer of warranties; and
15 * 2. No rights are granted, in any manner or form, to use Whistle
16 * Communications, Inc. trademarks, including the mark "WHISTLE
17 * COMMUNICATIONS" on advertising, endorsements, or otherwise except as
18 * such appears in the above copyright notice or in the software.
19 *
20 * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
21 * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
22 * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
23 * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
24 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
25 * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
26 * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
27 * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
28 * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
29 * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
30 * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
31 * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
32 * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
33 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
34 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
35 * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
36 * OF SUCH DAMAGE.
37 *
38 * Authors: Julian Elischer <julian@freebsd.org>
39 * Archie Cobbs <archie@freebsd.org>
40 *
41 * $FreeBSD$
42 * $Whistle: ng_base.c,v 1.39 1999/01/28 23:54:53 julian Exp $
43 */
44
45 /*
46 * This file implements the base netgraph code.
47 */
48
49 #include <sys/param.h>
50 #include <sys/systm.h>
51 #include <sys/ctype.h>
52 #include <sys/errno.h>
53 #include <sys/kdb.h>
54 #include <sys/kernel.h>
55 #include <sys/ktr.h>
56 #include <sys/limits.h>
57 #include <sys/malloc.h>
58 #include <sys/mbuf.h>
59 #include <sys/queue.h>
60 #include <sys/sysctl.h>
61 #include <sys/syslog.h>
62 #include <sys/refcount.h>
63 #include <sys/proc.h>
64 #include <machine/cpu.h>
65
66 #include <net/netisr.h>
67
68 #include <netgraph/ng_message.h>
69 #include <netgraph/netgraph.h>
70 #include <netgraph/ng_parse.h>
71
72 MODULE_VERSION(netgraph, NG_ABI_VERSION);
73
74 /* Mutex to protect topology events. */
75 static struct mtx ng_topo_mtx;
76
77 #ifdef NETGRAPH_DEBUG
78 static struct mtx ng_nodelist_mtx; /* protects global node/hook lists */
79 static struct mtx ngq_mtx; /* protects the queue item list */
80
81 static SLIST_HEAD(, ng_node) ng_allnodes;
82 static LIST_HEAD(, ng_node) ng_freenodes; /* in debug, we never free() them */
83 static SLIST_HEAD(, ng_hook) ng_allhooks;
84 static LIST_HEAD(, ng_hook) ng_freehooks; /* in debug, we never free() them */
85
86 static void ng_dumpitems(void);
87 static void ng_dumpnodes(void);
88 static void ng_dumphooks(void);
89
90 #endif /* NETGRAPH_DEBUG */
91 /*
92 * DEAD versions of the structures.
93 * In order to avoid races, it is sometimes neccesary to point
94 * at SOMETHING even though theoretically, the current entity is
95 * INVALID. Use these to avoid these races.
96 */
97 struct ng_type ng_deadtype = {
98 NG_ABI_VERSION,
99 "dead",
100 NULL, /* modevent */
101 NULL, /* constructor */
102 NULL, /* rcvmsg */
103 NULL, /* shutdown */
104 NULL, /* newhook */
105 NULL, /* findhook */
106 NULL, /* connect */
107 NULL, /* rcvdata */
108 NULL, /* disconnect */
109 NULL, /* cmdlist */
110 };
111
112 struct ng_node ng_deadnode = {
113 "dead",
114 &ng_deadtype,
115 NGF_INVALID,
116 1, /* refs */
117 0, /* numhooks */
118 NULL, /* private */
119 0, /* ID */
120 LIST_HEAD_INITIALIZER(ng_deadnode.hooks),
121 {}, /* all_nodes list entry */
122 {}, /* id hashtable list entry */
123 {}, /* workqueue entry */
124 { 0,
125 {}, /* should never use! (should hang) */
126 NULL,
127 &ng_deadnode.nd_input_queue.queue,
128 &ng_deadnode
129 },
130 #ifdef NETGRAPH_DEBUG
131 ND_MAGIC,
132 __FILE__,
133 __LINE__,
134 {NULL}
135 #endif /* NETGRAPH_DEBUG */
136 };
137
138 struct ng_hook ng_deadhook = {
139 "dead",
140 NULL, /* private */
141 HK_INVALID | HK_DEAD,
142 1, /* refs always >= 1 */
143 0, /* undefined data link type */
144 &ng_deadhook, /* Peer is self */
145 &ng_deadnode, /* attached to deadnode */
146 {}, /* hooks list */
147 NULL, /* override rcvmsg() */
148 NULL, /* override rcvdata() */
149 #ifdef NETGRAPH_DEBUG
150 HK_MAGIC,
151 __FILE__,
152 __LINE__,
153 {NULL}
154 #endif /* NETGRAPH_DEBUG */
155 };
156
157 /*
158 * END DEAD STRUCTURES
159 */
160 /* List nodes with unallocated work */
161 static TAILQ_HEAD(, ng_node) ng_worklist = TAILQ_HEAD_INITIALIZER(ng_worklist);
162 static struct mtx ng_worklist_mtx; /* MUST LOCK NODE FIRST */
163
164 /* List of installed types */
165 static LIST_HEAD(, ng_type) ng_typelist;
166 static struct mtx ng_typelist_mtx;
167
168 /* Hash related definitions */
169 /* XXX Don't need to initialise them because it's a LIST */
170 #define NG_ID_HASH_SIZE 128 /* most systems wont need even this many */
171 static LIST_HEAD(, ng_node) ng_ID_hash[NG_ID_HASH_SIZE];
172 static struct mtx ng_idhash_mtx;
173 /* Method to find a node.. used twice so do it here */
174 #define NG_IDHASH_FN(ID) ((ID) % (NG_ID_HASH_SIZE))
175 #define NG_IDHASH_FIND(ID, node) \
176 do { \
177 mtx_assert(&ng_idhash_mtx, MA_OWNED); \
178 LIST_FOREACH(node, &ng_ID_hash[NG_IDHASH_FN(ID)], \
179 nd_idnodes) { \
180 if (NG_NODE_IS_VALID(node) \
181 && (NG_NODE_ID(node) == ID)) { \
182 break; \
183 } \
184 } \
185 } while (0)
186
187 #define NG_NAME_HASH_SIZE 128 /* most systems wont need even this many */
188 static LIST_HEAD(, ng_node) ng_name_hash[NG_NAME_HASH_SIZE];
189 static struct mtx ng_namehash_mtx;
190 #define NG_NAMEHASH(NAME, HASH) \
191 do { \
192 u_char h = 0; \
193 const u_char *c; \
194 for (c = (const u_char*)(NAME); *c; c++)\
195 h += *c; \
196 (HASH) = h % (NG_NAME_HASH_SIZE); \
197 } while (0)
198
199
200 /* Internal functions */
201 static int ng_add_hook(node_p node, const char *name, hook_p * hookp);
202 static int ng_generic_msg(node_p here, item_p item, hook_p lasthook);
203 static ng_ID_t ng_decodeidname(const char *name);
204 static int ngb_mod_event(module_t mod, int event, void *data);
205 static void ng_worklist_add(node_p node);
206 static void ngintr(void);
207 static int ng_apply_item(node_p node, item_p item, int rw);
208 static void ng_flush_input_queue(struct ng_queue * ngq);
209 static node_p ng_ID2noderef(ng_ID_t ID);
210 static int ng_con_nodes(item_p item, node_p node, const char *name,
211 node_p node2, const char *name2);
212 static int ng_con_part2(node_p node, item_p item, hook_p hook);
213 static int ng_con_part3(node_p node, item_p item, hook_p hook);
214 static int ng_mkpeer(node_p node, const char *name,
215 const char *name2, char *type);
216
217 /* Imported, these used to be externally visible, some may go back. */
218 void ng_destroy_hook(hook_p hook);
219 node_p ng_name2noderef(node_p node, const char *name);
220 int ng_path2noderef(node_p here, const char *path,
221 node_p *dest, hook_p *lasthook);
222 int ng_make_node(const char *type, node_p *nodepp);
223 int ng_path_parse(char *addr, char **node, char **path, char **hook);
224 void ng_rmnode(node_p node, hook_p dummy1, void *dummy2, int dummy3);
225 void ng_unname(node_p node);
226
227
228 /* Our own netgraph malloc type */
229 MALLOC_DEFINE(M_NETGRAPH, "netgraph", "netgraph structures and ctrl messages");
230 MALLOC_DEFINE(M_NETGRAPH_HOOK, "netgraph_hook", "netgraph hook structures");
231 MALLOC_DEFINE(M_NETGRAPH_NODE, "netgraph_node", "netgraph node structures");
232 MALLOC_DEFINE(M_NETGRAPH_ITEM, "netgraph_item", "netgraph item structures");
233 MALLOC_DEFINE(M_NETGRAPH_MSG, "netgraph_msg", "netgraph name storage");
234
235 /* Should not be visible outside this file */
236
237 #define _NG_ALLOC_HOOK(hook) \
238 MALLOC(hook, hook_p, sizeof(*hook), M_NETGRAPH_HOOK, M_NOWAIT | M_ZERO)
239 #define _NG_ALLOC_NODE(node) \
240 MALLOC(node, node_p, sizeof(*node), M_NETGRAPH_NODE, M_NOWAIT | M_ZERO)
241
242 #define NG_QUEUE_LOCK_INIT(n) \
243 mtx_init(&(n)->q_mtx, "ng_node", NULL, MTX_DEF)
244 #define NG_QUEUE_LOCK(n) \
245 mtx_lock(&(n)->q_mtx)
246 #define NG_QUEUE_UNLOCK(n) \
247 mtx_unlock(&(n)->q_mtx)
248 #define NG_WORKLIST_LOCK_INIT() \
249 mtx_init(&ng_worklist_mtx, "ng_worklist", NULL, MTX_DEF)
250 #define NG_WORKLIST_LOCK() \
251 mtx_lock(&ng_worklist_mtx)
252 #define NG_WORKLIST_UNLOCK() \
253 mtx_unlock(&ng_worklist_mtx)
254
255 #ifdef NETGRAPH_DEBUG /*----------------------------------------------*/
256 /*
257 * In debug mode:
258 * In an attempt to help track reference count screwups
259 * we do not free objects back to the malloc system, but keep them
260 * in a local cache where we can examine them and keep information safely
261 * after they have been freed.
262 * We use this scheme for nodes and hooks, and to some extent for items.
263 */
264 static __inline hook_p
265 ng_alloc_hook(void)
266 {
267 hook_p hook;
268 SLIST_ENTRY(ng_hook) temp;
269 mtx_lock(&ng_nodelist_mtx);
270 hook = LIST_FIRST(&ng_freehooks);
271 if (hook) {
272 LIST_REMOVE(hook, hk_hooks);
273 bcopy(&hook->hk_all, &temp, sizeof(temp));
274 bzero(hook, sizeof(struct ng_hook));
275 bcopy(&temp, &hook->hk_all, sizeof(temp));
276 mtx_unlock(&ng_nodelist_mtx);
277 hook->hk_magic = HK_MAGIC;
278 } else {
279 mtx_unlock(&ng_nodelist_mtx);
280 _NG_ALLOC_HOOK(hook);
281 if (hook) {
282 hook->hk_magic = HK_MAGIC;
283 mtx_lock(&ng_nodelist_mtx);
284 SLIST_INSERT_HEAD(&ng_allhooks, hook, hk_all);
285 mtx_unlock(&ng_nodelist_mtx);
286 }
287 }
288 return (hook);
289 }
290
291 static __inline node_p
292 ng_alloc_node(void)
293 {
294 node_p node;
295 SLIST_ENTRY(ng_node) temp;
296 mtx_lock(&ng_nodelist_mtx);
297 node = LIST_FIRST(&ng_freenodes);
298 if (node) {
299 LIST_REMOVE(node, nd_nodes);
300 bcopy(&node->nd_all, &temp, sizeof(temp));
301 bzero(node, sizeof(struct ng_node));
302 bcopy(&temp, &node->nd_all, sizeof(temp));
303 mtx_unlock(&ng_nodelist_mtx);
304 node->nd_magic = ND_MAGIC;
305 } else {
306 mtx_unlock(&ng_nodelist_mtx);
307 _NG_ALLOC_NODE(node);
308 if (node) {
309 node->nd_magic = ND_MAGIC;
310 mtx_lock(&ng_nodelist_mtx);
311 SLIST_INSERT_HEAD(&ng_allnodes, node, nd_all);
312 mtx_unlock(&ng_nodelist_mtx);
313 }
314 }
315 return (node);
316 }
317
318 #define NG_ALLOC_HOOK(hook) do { (hook) = ng_alloc_hook(); } while (0)
319 #define NG_ALLOC_NODE(node) do { (node) = ng_alloc_node(); } while (0)
320
321
322 #define NG_FREE_HOOK(hook) \
323 do { \
324 mtx_lock(&ng_nodelist_mtx); \
325 LIST_INSERT_HEAD(&ng_freehooks, hook, hk_hooks); \
326 hook->hk_magic = 0; \
327 mtx_unlock(&ng_nodelist_mtx); \
328 } while (0)
329
330 #define NG_FREE_NODE(node) \
331 do { \
332 mtx_lock(&ng_nodelist_mtx); \
333 LIST_INSERT_HEAD(&ng_freenodes, node, nd_nodes); \
334 node->nd_magic = 0; \
335 mtx_unlock(&ng_nodelist_mtx); \
336 } while (0)
337
338 #else /* NETGRAPH_DEBUG */ /*----------------------------------------------*/
339
340 #define NG_ALLOC_HOOK(hook) _NG_ALLOC_HOOK(hook)
341 #define NG_ALLOC_NODE(node) _NG_ALLOC_NODE(node)
342
343 #define NG_FREE_HOOK(hook) do { FREE((hook), M_NETGRAPH_HOOK); } while (0)
344 #define NG_FREE_NODE(node) do { FREE((node), M_NETGRAPH_NODE); } while (0)
345
346 #endif /* NETGRAPH_DEBUG */ /*----------------------------------------------*/
347
348 /* Set this to kdb_enter("X") to catch all errors as they occur */
349 #ifndef TRAP_ERROR
350 #define TRAP_ERROR()
351 #endif
352
353 static ng_ID_t nextID = 1;
354
355 #ifdef INVARIANTS
356 #define CHECK_DATA_MBUF(m) do { \
357 struct mbuf *n; \
358 int total; \
359 \
360 M_ASSERTPKTHDR(m); \
361 for (total = 0, n = (m); n != NULL; n = n->m_next) { \
362 total += n->m_len; \
363 if (n->m_nextpkt != NULL) \
364 panic("%s: m_nextpkt", __func__); \
365 } \
366 \
367 if ((m)->m_pkthdr.len != total) { \
368 panic("%s: %d != %d", \
369 __func__, (m)->m_pkthdr.len, total); \
370 } \
371 } while (0)
372 #else
373 #define CHECK_DATA_MBUF(m)
374 #endif
375
376 #define ERROUT(x) do { error = (x); goto done; } while (0)
377
378 /************************************************************************
379 Parse type definitions for generic messages
380 ************************************************************************/
381
382 /* Handy structure parse type defining macro */
383 #define DEFINE_PARSE_STRUCT_TYPE(lo, up, args) \
384 static const struct ng_parse_struct_field \
385 ng_ ## lo ## _type_fields[] = NG_GENERIC_ ## up ## _INFO args; \
386 static const struct ng_parse_type ng_generic_ ## lo ## _type = { \
387 &ng_parse_struct_type, \
388 &ng_ ## lo ## _type_fields \
389 }
390
391 DEFINE_PARSE_STRUCT_TYPE(mkpeer, MKPEER, ());
392 DEFINE_PARSE_STRUCT_TYPE(connect, CONNECT, ());
393 DEFINE_PARSE_STRUCT_TYPE(name, NAME, ());
394 DEFINE_PARSE_STRUCT_TYPE(rmhook, RMHOOK, ());
395 DEFINE_PARSE_STRUCT_TYPE(nodeinfo, NODEINFO, ());
396 DEFINE_PARSE_STRUCT_TYPE(typeinfo, TYPEINFO, ());
397 DEFINE_PARSE_STRUCT_TYPE(linkinfo, LINKINFO, (&ng_generic_nodeinfo_type));
398
399 /* Get length of an array when the length is stored as a 32 bit
400 value immediately preceding the array -- as with struct namelist
401 and struct typelist. */
402 static int
403 ng_generic_list_getLength(const struct ng_parse_type *type,
404 const u_char *start, const u_char *buf)
405 {
406 return *((const u_int32_t *)(buf - 4));
407 }
408
409 /* Get length of the array of struct linkinfo inside a struct hooklist */
410 static int
411 ng_generic_linkinfo_getLength(const struct ng_parse_type *type,
412 const u_char *start, const u_char *buf)
413 {
414 const struct hooklist *hl = (const struct hooklist *)start;
415
416 return hl->nodeinfo.hooks;
417 }
418
419 /* Array type for a variable length array of struct namelist */
420 static const struct ng_parse_array_info ng_nodeinfoarray_type_info = {
421 &ng_generic_nodeinfo_type,
422 &ng_generic_list_getLength
423 };
424 static const struct ng_parse_type ng_generic_nodeinfoarray_type = {
425 &ng_parse_array_type,
426 &ng_nodeinfoarray_type_info
427 };
428
429 /* Array type for a variable length array of struct typelist */
430 static const struct ng_parse_array_info ng_typeinfoarray_type_info = {
431 &ng_generic_typeinfo_type,
432 &ng_generic_list_getLength
433 };
434 static const struct ng_parse_type ng_generic_typeinfoarray_type = {
435 &ng_parse_array_type,
436 &ng_typeinfoarray_type_info
437 };
438
439 /* Array type for array of struct linkinfo in struct hooklist */
440 static const struct ng_parse_array_info ng_generic_linkinfo_array_type_info = {
441 &ng_generic_linkinfo_type,
442 &ng_generic_linkinfo_getLength
443 };
444 static const struct ng_parse_type ng_generic_linkinfo_array_type = {
445 &ng_parse_array_type,
446 &ng_generic_linkinfo_array_type_info
447 };
448
449 DEFINE_PARSE_STRUCT_TYPE(typelist, TYPELIST, (&ng_generic_nodeinfoarray_type));
450 DEFINE_PARSE_STRUCT_TYPE(hooklist, HOOKLIST,
451 (&ng_generic_nodeinfo_type, &ng_generic_linkinfo_array_type));
452 DEFINE_PARSE_STRUCT_TYPE(listnodes, LISTNODES,
453 (&ng_generic_nodeinfoarray_type));
454
455 /* List of commands and how to convert arguments to/from ASCII */
456 static const struct ng_cmdlist ng_generic_cmds[] = {
457 {
458 NGM_GENERIC_COOKIE,
459 NGM_SHUTDOWN,
460 "shutdown",
461 NULL,
462 NULL
463 },
464 {
465 NGM_GENERIC_COOKIE,
466 NGM_MKPEER,
467 "mkpeer",
468 &ng_generic_mkpeer_type,
469 NULL
470 },
471 {
472 NGM_GENERIC_COOKIE,
473 NGM_CONNECT,
474 "connect",
475 &ng_generic_connect_type,
476 NULL
477 },
478 {
479 NGM_GENERIC_COOKIE,
480 NGM_NAME,
481 "name",
482 &ng_generic_name_type,
483 NULL
484 },
485 {
486 NGM_GENERIC_COOKIE,
487 NGM_RMHOOK,
488 "rmhook",
489 &ng_generic_rmhook_type,
490 NULL
491 },
492 {
493 NGM_GENERIC_COOKIE,
494 NGM_NODEINFO,
495 "nodeinfo",
496 NULL,
497 &ng_generic_nodeinfo_type
498 },
499 {
500 NGM_GENERIC_COOKIE,
501 NGM_LISTHOOKS,
502 "listhooks",
503 NULL,
504 &ng_generic_hooklist_type
505 },
506 {
507 NGM_GENERIC_COOKIE,
508 NGM_LISTNAMES,
509 "listnames",
510 NULL,
511 &ng_generic_listnodes_type /* same as NGM_LISTNODES */
512 },
513 {
514 NGM_GENERIC_COOKIE,
515 NGM_LISTNODES,
516 "listnodes",
517 NULL,
518 &ng_generic_listnodes_type
519 },
520 {
521 NGM_GENERIC_COOKIE,
522 NGM_LISTTYPES,
523 "listtypes",
524 NULL,
525 &ng_generic_typeinfo_type
526 },
527 {
528 NGM_GENERIC_COOKIE,
529 NGM_TEXT_CONFIG,
530 "textconfig",
531 NULL,
532 &ng_parse_string_type
533 },
534 {
535 NGM_GENERIC_COOKIE,
536 NGM_TEXT_STATUS,
537 "textstatus",
538 NULL,
539 &ng_parse_string_type
540 },
541 {
542 NGM_GENERIC_COOKIE,
543 NGM_ASCII2BINARY,
544 "ascii2binary",
545 &ng_parse_ng_mesg_type,
546 &ng_parse_ng_mesg_type
547 },
548 {
549 NGM_GENERIC_COOKIE,
550 NGM_BINARY2ASCII,
551 "binary2ascii",
552 &ng_parse_ng_mesg_type,
553 &ng_parse_ng_mesg_type
554 },
555 { 0 }
556 };
557
558 /************************************************************************
559 Node routines
560 ************************************************************************/
561
562 /*
563 * Instantiate a node of the requested type
564 */
565 int
566 ng_make_node(const char *typename, node_p *nodepp)
567 {
568 struct ng_type *type;
569 int error;
570
571 /* Check that the type makes sense */
572 if (typename == NULL) {
573 TRAP_ERROR();
574 return (EINVAL);
575 }
576
577 /* Locate the node type. If we fail we return. Do not try to load
578 * module.
579 */
580 if ((type = ng_findtype(typename)) == NULL)
581 return (ENXIO);
582
583 /*
584 * If we have a constructor, then make the node and
585 * call the constructor to do type specific initialisation.
586 */
587 if (type->constructor != NULL) {
588 if ((error = ng_make_node_common(type, nodepp)) == 0) {
589 if ((error = ((*type->constructor)(*nodepp)) != 0)) {
590 NG_NODE_UNREF(*nodepp);
591 }
592 }
593 } else {
594 /*
595 * Node has no constructor. We cannot ask for one
596 * to be made. It must be brought into existence by
597 * some external agency. The external agency should
598 * call ng_make_node_common() directly to get the
599 * netgraph part initialised.
600 */
601 TRAP_ERROR();
602 error = EINVAL;
603 }
604 return (error);
605 }
606
607 /*
608 * Generic node creation. Called by node initialisation for externally
609 * instantiated nodes (e.g. hardware, sockets, etc ).
610 * The returned node has a reference count of 1.
611 */
612 int
613 ng_make_node_common(struct ng_type *type, node_p *nodepp)
614 {
615 node_p node;
616
617 /* Require the node type to have been already installed */
618 if (ng_findtype(type->name) == NULL) {
619 TRAP_ERROR();
620 return (EINVAL);
621 }
622
623 /* Make a node and try attach it to the type */
624 NG_ALLOC_NODE(node);
625 if (node == NULL) {
626 TRAP_ERROR();
627 return (ENOMEM);
628 }
629 node->nd_type = type;
630 NG_NODE_REF(node); /* note reference */
631 type->refs++;
632
633 NG_QUEUE_LOCK_INIT(&node->nd_input_queue);
634 node->nd_input_queue.queue = NULL;
635 node->nd_input_queue.last = &node->nd_input_queue.queue;
636 node->nd_input_queue.q_flags = 0;
637 node->nd_input_queue.q_node = node;
638
639 /* Initialize hook list for new node */
640 LIST_INIT(&node->nd_hooks);
641
642 /* Link us into the name hash. */
643 mtx_lock(&ng_namehash_mtx);
644 LIST_INSERT_HEAD(&ng_name_hash[0], node, nd_nodes);
645 mtx_unlock(&ng_namehash_mtx);
646
647 /* get an ID and put us in the hash chain */
648 mtx_lock(&ng_idhash_mtx);
649 for (;;) { /* wrap protection, even if silly */
650 node_p node2 = NULL;
651 node->nd_ID = nextID++; /* 137/second for 1 year before wrap */
652
653 /* Is there a problem with the new number? */
654 NG_IDHASH_FIND(node->nd_ID, node2); /* already taken? */
655 if ((node->nd_ID != 0) && (node2 == NULL)) {
656 break;
657 }
658 }
659 LIST_INSERT_HEAD(&ng_ID_hash[NG_IDHASH_FN(node->nd_ID)],
660 node, nd_idnodes);
661 mtx_unlock(&ng_idhash_mtx);
662
663 /* Done */
664 *nodepp = node;
665 return (0);
666 }
667
668 /*
669 * Forceably start the shutdown process on a node. Either call
670 * its shutdown method, or do the default shutdown if there is
671 * no type-specific method.
672 *
673 * We can only be called from a shutdown message, so we know we have
674 * a writer lock, and therefore exclusive access. It also means
675 * that we should not be on the work queue, but we check anyhow.
676 *
677 * Persistent node types must have a type-specific method which
678 * allocates a new node in which case, this one is irretrievably going away,
679 * or cleans up anything it needs, and just makes the node valid again,
680 * in which case we allow the node to survive.
681 *
682 * XXX We need to think of how to tell a persistent node that we
683 * REALLY need to go away because the hardware has gone or we
684 * are rebooting.... etc.
685 */
686 void
687 ng_rmnode(node_p node, hook_p dummy1, void *dummy2, int dummy3)
688 {
689 hook_p hook;
690
691 /* Check if it's already shutting down */
692 if ((node->nd_flags & NGF_CLOSING) != 0)
693 return;
694
695 if (node == &ng_deadnode) {
696 printf ("shutdown called on deadnode\n");
697 return;
698 }
699
700 /* Add an extra reference so it doesn't go away during this */
701 NG_NODE_REF(node);
702
703 /*
704 * Mark it invalid so any newcomers know not to try use it
705 * Also add our own mark so we can't recurse
706 * note that NGF_INVALID does not do this as it's also set during
707 * creation
708 */
709 node->nd_flags |= NGF_INVALID|NGF_CLOSING;
710
711 /* If node has its pre-shutdown method, then call it first*/
712 if (node->nd_type && node->nd_type->close)
713 (*node->nd_type->close)(node);
714
715 /* Notify all remaining connected nodes to disconnect */
716 while ((hook = LIST_FIRST(&node->nd_hooks)) != NULL)
717 ng_destroy_hook(hook);
718
719 /*
720 * Drain the input queue forceably.
721 * it has no hooks so what's it going to do, bleed on someone?
722 * Theoretically we came here from a queue entry that was added
723 * Just before the queue was closed, so it should be empty anyway.
724 * Also removes us from worklist if needed.
725 */
726 ng_flush_input_queue(&node->nd_input_queue);
727
728 /* Ask the type if it has anything to do in this case */
729 if (node->nd_type && node->nd_type->shutdown) {
730 (*node->nd_type->shutdown)(node);
731 if (NG_NODE_IS_VALID(node)) {
732 /*
733 * Well, blow me down if the node code hasn't declared
734 * that it doesn't want to die.
735 * Presumably it is a persistant node.
736 * If we REALLY want it to go away,
737 * e.g. hardware going away,
738 * Our caller should set NGF_REALLY_DIE in nd_flags.
739 */
740 node->nd_flags &= ~(NGF_INVALID|NGF_CLOSING);
741 NG_NODE_UNREF(node); /* Assume they still have theirs */
742 return;
743 }
744 } else { /* do the default thing */
745 NG_NODE_UNREF(node);
746 }
747
748 ng_unname(node); /* basically a NOP these days */
749
750 /*
751 * Remove extra reference, possibly the last
752 * Possible other holders of references may include
753 * timeout callouts, but theoretically the node's supposed to
754 * have cancelled them. Possibly hardware dependencies may
755 * force a driver to 'linger' with a reference.
756 */
757 NG_NODE_UNREF(node);
758 }
759
760 /*
761 * Remove a reference to the node, possibly the last.
762 * deadnode always acts as it it were the last.
763 */
764 int
765 ng_unref_node(node_p node)
766 {
767 int v;
768
769 if (node == &ng_deadnode) {
770 return (0);
771 }
772
773 v = atomic_fetchadd_int(&node->nd_refs, -1);
774
775 if (v == 1) { /* we were the last */
776
777 mtx_lock(&ng_namehash_mtx);
778 node->nd_type->refs--; /* XXX maybe should get types lock? */
779 LIST_REMOVE(node, nd_nodes);
780 mtx_unlock(&ng_namehash_mtx);
781
782 mtx_lock(&ng_idhash_mtx);
783 LIST_REMOVE(node, nd_idnodes);
784 mtx_unlock(&ng_idhash_mtx);
785
786 mtx_destroy(&node->nd_input_queue.q_mtx);
787 NG_FREE_NODE(node);
788 }
789 return (v - 1);
790 }
791
792 /************************************************************************
793 Node ID handling
794 ************************************************************************/
795 static node_p
796 ng_ID2noderef(ng_ID_t ID)
797 {
798 node_p node;
799 mtx_lock(&ng_idhash_mtx);
800 NG_IDHASH_FIND(ID, node);
801 if(node)
802 NG_NODE_REF(node);
803 mtx_unlock(&ng_idhash_mtx);
804 return(node);
805 }
806
807 ng_ID_t
808 ng_node2ID(node_p node)
809 {
810 return (node ? NG_NODE_ID(node) : 0);
811 }
812
813 /************************************************************************
814 Node name handling
815 ************************************************************************/
816
817 /*
818 * Assign a node a name. Once assigned, the name cannot be changed.
819 */
820 int
821 ng_name_node(node_p node, const char *name)
822 {
823 int i, hash;
824 node_p node2;
825
826 /* Check the name is valid */
827 for (i = 0; i < NG_NODESIZ; i++) {
828 if (name[i] == '\0' || name[i] == '.' || name[i] == ':')
829 break;
830 }
831 if (i == 0 || name[i] != '\0') {
832 TRAP_ERROR();
833 return (EINVAL);
834 }
835 if (ng_decodeidname(name) != 0) { /* valid IDs not allowed here */
836 TRAP_ERROR();
837 return (EINVAL);
838 }
839
840 /* Check the name isn't already being used */
841 if ((node2 = ng_name2noderef(node, name)) != NULL) {
842 NG_NODE_UNREF(node2);
843 TRAP_ERROR();
844 return (EADDRINUSE);
845 }
846
847 /* copy it */
848 strlcpy(NG_NODE_NAME(node), name, NG_NODESIZ);
849
850 /* Update name hash. */
851 NG_NAMEHASH(name, hash);
852 mtx_lock(&ng_namehash_mtx);
853 LIST_REMOVE(node, nd_nodes);
854 LIST_INSERT_HEAD(&ng_name_hash[hash], node, nd_nodes);
855 mtx_unlock(&ng_namehash_mtx);
856
857 return (0);
858 }
859
860 /*
861 * Find a node by absolute name. The name should NOT end with ':'
862 * The name "." means "this node" and "[xxx]" means "the node
863 * with ID (ie, at address) xxx".
864 *
865 * Returns the node if found, else NULL.
866 * Eventually should add something faster than a sequential search.
867 * Note it acquires a reference on the node so you can be sure it's still
868 * there.
869 */
870 node_p
871 ng_name2noderef(node_p here, const char *name)
872 {
873 node_p node;
874 ng_ID_t temp;
875 int hash;
876
877 /* "." means "this node" */
878 if (strcmp(name, ".") == 0) {
879 NG_NODE_REF(here);
880 return(here);
881 }
882
883 /* Check for name-by-ID */
884 if ((temp = ng_decodeidname(name)) != 0) {
885 return (ng_ID2noderef(temp));
886 }
887
888 /* Find node by name */
889 NG_NAMEHASH(name, hash);
890 mtx_lock(&ng_namehash_mtx);
891 LIST_FOREACH(node, &ng_name_hash[hash], nd_nodes) {
892 if (NG_NODE_IS_VALID(node) &&
893 (strcmp(NG_NODE_NAME(node), name) == 0)) {
894 break;
895 }
896 }
897 if (node)
898 NG_NODE_REF(node);
899 mtx_unlock(&ng_namehash_mtx);
900 return (node);
901 }
902
903 /*
904 * Decode an ID name, eg. "[f03034de]". Returns 0 if the
905 * string is not valid, otherwise returns the value.
906 */
907 static ng_ID_t
908 ng_decodeidname(const char *name)
909 {
910 const int len = strlen(name);
911 char *eptr;
912 u_long val;
913
914 /* Check for proper length, brackets, no leading junk */
915 if ((len < 3)
916 || (name[0] != '[')
917 || (name[len - 1] != ']')
918 || (!isxdigit(name[1]))) {
919 return ((ng_ID_t)0);
920 }
921
922 /* Decode number */
923 val = strtoul(name + 1, &eptr, 16);
924 if ((eptr - name != len - 1)
925 || (val == ULONG_MAX)
926 || (val == 0)) {
927 return ((ng_ID_t)0);
928 }
929 return (ng_ID_t)val;
930 }
931
932 /*
933 * Remove a name from a node. This should only be called
934 * when shutting down and removing the node.
935 * IF we allow name changing this may be more resurrected.
936 */
937 void
938 ng_unname(node_p node)
939 {
940 }
941
942 /************************************************************************
943 Hook routines
944 Names are not optional. Hooks are always connected, except for a
945 brief moment within these routines. On invalidation or during creation
946 they are connected to the 'dead' hook.
947 ************************************************************************/
948
949 /*
950 * Remove a hook reference
951 */
952 void
953 ng_unref_hook(hook_p hook)
954 {
955 int v;
956
957 if (hook == &ng_deadhook) {
958 return;
959 }
960
961 v = atomic_fetchadd_int(&hook->hk_refs, -1);
962
963 if (v == 1) { /* we were the last */
964 if (_NG_HOOK_NODE(hook)) /* it'll probably be ng_deadnode */
965 _NG_NODE_UNREF((_NG_HOOK_NODE(hook)));
966 NG_FREE_HOOK(hook);
967 }
968 }
969
970 /*
971 * Add an unconnected hook to a node. Only used internally.
972 * Assumes node is locked. (XXX not yet true )
973 */
974 static int
975 ng_add_hook(node_p node, const char *name, hook_p *hookp)
976 {
977 hook_p hook;
978 int error = 0;
979
980 /* Check that the given name is good */
981 if (name == NULL) {
982 TRAP_ERROR();
983 return (EINVAL);
984 }
985 if (ng_findhook(node, name) != NULL) {
986 TRAP_ERROR();
987 return (EEXIST);
988 }
989
990 /* Allocate the hook and link it up */
991 NG_ALLOC_HOOK(hook);
992 if (hook == NULL) {
993 TRAP_ERROR();
994 return (ENOMEM);
995 }
996 hook->hk_refs = 1; /* add a reference for us to return */
997 hook->hk_flags = HK_INVALID;
998 hook->hk_peer = &ng_deadhook; /* start off this way */
999 hook->hk_node = node;
1000 NG_NODE_REF(node); /* each hook counts as a reference */
1001
1002 /* Set hook name */
1003 strlcpy(NG_HOOK_NAME(hook), name, NG_HOOKSIZ);
1004
1005 /*
1006 * Check if the node type code has something to say about it
1007 * If it fails, the unref of the hook will also unref the node.
1008 */
1009 if (node->nd_type->newhook != NULL) {
1010 if ((error = (*node->nd_type->newhook)(node, hook, name))) {
1011 NG_HOOK_UNREF(hook); /* this frees the hook */
1012 return (error);
1013 }
1014 }
1015 /*
1016 * The 'type' agrees so far, so go ahead and link it in.
1017 * We'll ask again later when we actually connect the hooks.
1018 */
1019 LIST_INSERT_HEAD(&node->nd_hooks, hook, hk_hooks);
1020 node->nd_numhooks++;
1021 NG_HOOK_REF(hook); /* one for the node */
1022
1023 if (hookp)
1024 *hookp = hook;
1025 return (0);
1026 }
1027
1028 /*
1029 * Find a hook
1030 *
1031 * Node types may supply their own optimized routines for finding
1032 * hooks. If none is supplied, we just do a linear search.
1033 * XXX Possibly we should add a reference to the hook?
1034 */
1035 hook_p
1036 ng_findhook(node_p node, const char *name)
1037 {
1038 hook_p hook;
1039
1040 if (node->nd_type->findhook != NULL)
1041 return (*node->nd_type->findhook)(node, name);
1042 LIST_FOREACH(hook, &node->nd_hooks, hk_hooks) {
1043 if (NG_HOOK_IS_VALID(hook)
1044 && (strcmp(NG_HOOK_NAME(hook), name) == 0))
1045 return (hook);
1046 }
1047 return (NULL);
1048 }
1049
1050 /*
1051 * Destroy a hook
1052 *
1053 * As hooks are always attached, this really destroys two hooks.
1054 * The one given, and the one attached to it. Disconnect the hooks
1055 * from each other first. We reconnect the peer hook to the 'dead'
1056 * hook so that it can still exist after we depart. We then
1057 * send the peer its own destroy message. This ensures that we only
1058 * interact with the peer's structures when it is locked processing that
1059 * message. We hold a reference to the peer hook so we are guaranteed that
1060 * the peer hook and node are still going to exist until
1061 * we are finished there as the hook holds a ref on the node.
1062 * We run this same code again on the peer hook, but that time it is already
1063 * attached to the 'dead' hook.
1064 *
1065 * This routine is called at all stages of hook creation
1066 * on error detection and must be able to handle any such stage.
1067 */
1068 void
1069 ng_destroy_hook(hook_p hook)
1070 {
1071 hook_p peer;
1072 node_p node;
1073
1074 if (hook == &ng_deadhook) { /* better safe than sorry */
1075 printf("ng_destroy_hook called on deadhook\n");
1076 return;
1077 }
1078
1079 /*
1080 * Protect divorce process with mutex, to avoid races on
1081 * simultaneous disconnect.
1082 */
1083 mtx_lock(&ng_topo_mtx);
1084
1085 hook->hk_flags |= HK_INVALID;
1086
1087 peer = NG_HOOK_PEER(hook);
1088 node = NG_HOOK_NODE(hook);
1089
1090 if (peer && (peer != &ng_deadhook)) {
1091 /*
1092 * Set the peer to point to ng_deadhook
1093 * from this moment on we are effectively independent it.
1094 * send it an rmhook message of it's own.
1095 */
1096 peer->hk_peer = &ng_deadhook; /* They no longer know us */
1097 hook->hk_peer = &ng_deadhook; /* Nor us, them */
1098 if (NG_HOOK_NODE(peer) == &ng_deadnode) {
1099 /*
1100 * If it's already divorced from a node,
1101 * just free it.
1102 */
1103 mtx_unlock(&ng_topo_mtx);
1104 } else {
1105 mtx_unlock(&ng_topo_mtx);
1106 ng_rmhook_self(peer); /* Send it a surprise */
1107 }
1108 NG_HOOK_UNREF(peer); /* account for peer link */
1109 NG_HOOK_UNREF(hook); /* account for peer link */
1110 } else
1111 mtx_unlock(&ng_topo_mtx);
1112
1113 mtx_assert(&ng_topo_mtx, MA_NOTOWNED);
1114
1115 /*
1116 * Remove the hook from the node's list to avoid possible recursion
1117 * in case the disconnection results in node shutdown.
1118 */
1119 if (node == &ng_deadnode) { /* happens if called from ng_con_nodes() */
1120 return;
1121 }
1122 LIST_REMOVE(hook, hk_hooks);
1123 node->nd_numhooks--;
1124 if (node->nd_type->disconnect) {
1125 /*
1126 * The type handler may elect to destroy the node so don't
1127 * trust its existence after this point. (except
1128 * that we still hold a reference on it. (which we
1129 * inherrited from the hook we are destroying)
1130 */
1131 (*node->nd_type->disconnect) (hook);
1132 }
1133
1134 /*
1135 * Note that because we will point to ng_deadnode, the original node
1136 * is not decremented automatically so we do that manually.
1137 */
1138 _NG_HOOK_NODE(hook) = &ng_deadnode;
1139 NG_NODE_UNREF(node); /* We no longer point to it so adjust count */
1140 NG_HOOK_UNREF(hook); /* Account for linkage (in list) to node */
1141 }
1142
1143 /*
1144 * Take two hooks on a node and merge the connection so that the given node
1145 * is effectively bypassed.
1146 */
1147 int
1148 ng_bypass(hook_p hook1, hook_p hook2)
1149 {
1150 if (hook1->hk_node != hook2->hk_node) {
1151 TRAP_ERROR();
1152 return (EINVAL);
1153 }
1154 hook1->hk_peer->hk_peer = hook2->hk_peer;
1155 hook2->hk_peer->hk_peer = hook1->hk_peer;
1156
1157 hook1->hk_peer = &ng_deadhook;
1158 hook2->hk_peer = &ng_deadhook;
1159
1160 NG_HOOK_UNREF(hook1);
1161 NG_HOOK_UNREF(hook2);
1162
1163 /* XXX If we ever cache methods on hooks update them as well */
1164 ng_destroy_hook(hook1);
1165 ng_destroy_hook(hook2);
1166 return (0);
1167 }
1168
1169 /*
1170 * Install a new netgraph type
1171 */
1172 int
1173 ng_newtype(struct ng_type *tp)
1174 {
1175 const size_t namelen = strlen(tp->name);
1176
1177 /* Check version and type name fields */
1178 if ((tp->version != NG_ABI_VERSION)
1179 || (namelen == 0)
1180 || (namelen >= NG_TYPESIZ)) {
1181 TRAP_ERROR();
1182 if (tp->version != NG_ABI_VERSION) {
1183 printf("Netgraph: Node type rejected. ABI mismatch. Suggest recompile\n");
1184 }
1185 return (EINVAL);
1186 }
1187
1188 /* Check for name collision */
1189 if (ng_findtype(tp->name) != NULL) {
1190 TRAP_ERROR();
1191 return (EEXIST);
1192 }
1193
1194
1195 /* Link in new type */
1196 mtx_lock(&ng_typelist_mtx);
1197 LIST_INSERT_HEAD(&ng_typelist, tp, types);
1198 tp->refs = 1; /* first ref is linked list */
1199 mtx_unlock(&ng_typelist_mtx);
1200 return (0);
1201 }
1202
1203 /*
1204 * unlink a netgraph type
1205 * If no examples exist
1206 */
1207 int
1208 ng_rmtype(struct ng_type *tp)
1209 {
1210 /* Check for name collision */
1211 if (tp->refs != 1) {
1212 TRAP_ERROR();
1213 return (EBUSY);
1214 }
1215
1216 /* Unlink type */
1217 mtx_lock(&ng_typelist_mtx);
1218 LIST_REMOVE(tp, types);
1219 mtx_unlock(&ng_typelist_mtx);
1220 return (0);
1221 }
1222
1223 /*
1224 * Look for a type of the name given
1225 */
1226 struct ng_type *
1227 ng_findtype(const char *typename)
1228 {
1229 struct ng_type *type;
1230
1231 mtx_lock(&ng_typelist_mtx);
1232 LIST_FOREACH(type, &ng_typelist, types) {
1233 if (strcmp(type->name, typename) == 0)
1234 break;
1235 }
1236 mtx_unlock(&ng_typelist_mtx);
1237 return (type);
1238 }
1239
1240 /************************************************************************
1241 Composite routines
1242 ************************************************************************/
1243 /*
1244 * Connect two nodes using the specified hooks, using queued functions.
1245 */
1246 static int
1247 ng_con_part3(node_p node, item_p item, hook_p hook)
1248 {
1249 int error = 0;
1250
1251 /*
1252 * When we run, we know that the node 'node' is locked for us.
1253 * Our caller has a reference on the hook.
1254 * Our caller has a reference on the node.
1255 * (In this case our caller is ng_apply_item() ).
1256 * The peer hook has a reference on the hook.
1257 * We are all set up except for the final call to the node, and
1258 * the clearing of the INVALID flag.
1259 */
1260 if (NG_HOOK_NODE(hook) == &ng_deadnode) {
1261 /*
1262 * The node must have been freed again since we last visited
1263 * here. ng_destry_hook() has this effect but nothing else does.
1264 * We should just release our references and
1265 * free anything we can think of.
1266 * Since we know it's been destroyed, and it's our caller
1267 * that holds the references, just return.
1268 */
1269 ERROUT(ENOENT);
1270 }
1271 if (hook->hk_node->nd_type->connect) {
1272 if ((error = (*hook->hk_node->nd_type->connect) (hook))) {
1273 ng_destroy_hook(hook); /* also zaps peer */
1274 printf("failed in ng_con_part3()\n");
1275 ERROUT(error);
1276 }
1277 }
1278 /*
1279 * XXX this is wrong for SMP. Possibly we need
1280 * to separate out 'create' and 'invalid' flags.
1281 * should only set flags on hooks we have locked under our node.
1282 */
1283 hook->hk_flags &= ~HK_INVALID;
1284 done:
1285 NG_FREE_ITEM(item);
1286 return (error);
1287 }
1288
1289 static int
1290 ng_con_part2(node_p node, item_p item, hook_p hook)
1291 {
1292 hook_p peer;
1293 int error = 0;
1294
1295 /*
1296 * When we run, we know that the node 'node' is locked for us.
1297 * Our caller has a reference on the hook.
1298 * Our caller has a reference on the node.
1299 * (In this case our caller is ng_apply_item() ).
1300 * The peer hook has a reference on the hook.
1301 * our node pointer points to the 'dead' node.
1302 * First check the hook name is unique.
1303 * Should not happen because we checked before queueing this.
1304 */
1305 if (ng_findhook(node, NG_HOOK_NAME(hook)) != NULL) {
1306 TRAP_ERROR();
1307 ng_destroy_hook(hook); /* should destroy peer too */
1308 printf("failed in ng_con_part2()\n");
1309 ERROUT(EEXIST);
1310 }
1311 /*
1312 * Check if the node type code has something to say about it
1313 * If it fails, the unref of the hook will also unref the attached node,
1314 * however since that node is 'ng_deadnode' this will do nothing.
1315 * The peer hook will also be destroyed.
1316 */
1317 if (node->nd_type->newhook != NULL) {
1318 if ((error = (*node->nd_type->newhook)(node, hook,
1319 hook->hk_name))) {
1320 ng_destroy_hook(hook); /* should destroy peer too */
1321 printf("failed in ng_con_part2()\n");
1322 ERROUT(error);
1323 }
1324 }
1325
1326 /*
1327 * The 'type' agrees so far, so go ahead and link it in.
1328 * We'll ask again later when we actually connect the hooks.
1329 */
1330 hook->hk_node = node; /* just overwrite ng_deadnode */
1331 NG_NODE_REF(node); /* each hook counts as a reference */
1332 LIST_INSERT_HEAD(&node->nd_hooks, hook, hk_hooks);
1333 node->nd_numhooks++;
1334 NG_HOOK_REF(hook); /* one for the node */
1335
1336 /*
1337 * We now have a symmetrical situation, where both hooks have been
1338 * linked to their nodes, the newhook methods have been called
1339 * And the references are all correct. The hooks are still marked
1340 * as invalid, as we have not called the 'connect' methods
1341 * yet.
1342 * We can call the local one immediately as we have the
1343 * node locked, but we need to queue the remote one.
1344 */
1345 if (hook->hk_node->nd_type->connect) {
1346 if ((error = (*hook->hk_node->nd_type->connect) (hook))) {
1347 ng_destroy_hook(hook); /* also zaps peer */
1348 printf("failed in ng_con_part2(A)\n");
1349 ERROUT(error);
1350 }
1351 }
1352
1353 /*
1354 * Acquire topo mutex to avoid race with ng_destroy_hook().
1355 */
1356 mtx_lock(&ng_topo_mtx);
1357 peer = hook->hk_peer;
1358 if (peer == &ng_deadhook) {
1359 mtx_unlock(&ng_topo_mtx);
1360 printf("failed in ng_con_part2(B)\n");
1361 ng_destroy_hook(hook);
1362 ERROUT(ENOENT);
1363 }
1364 mtx_unlock(&ng_topo_mtx);
1365
1366 if ((error = ng_send_fn2(peer->hk_node, peer, item, &ng_con_part3,
1367 NULL, 0, NG_REUSE_ITEM))) {
1368 printf("failed in ng_con_part2(C)\n");
1369 ng_destroy_hook(hook); /* also zaps peer */
1370 return (error); /* item was consumed. */
1371 }
1372 hook->hk_flags &= ~HK_INVALID; /* need both to be able to work */
1373 return (0); /* item was consumed. */
1374 done:
1375 NG_FREE_ITEM(item);
1376 return (error);
1377 }
1378
1379 /*
1380 * Connect this node with another node. We assume that this node is
1381 * currently locked, as we are only called from an NGM_CONNECT message.
1382 */
1383 static int
1384 ng_con_nodes(item_p item, node_p node, const char *name,
1385 node_p node2, const char *name2)
1386 {
1387 int error;
1388 hook_p hook;
1389 hook_p hook2;
1390
1391 if (ng_findhook(node2, name2) != NULL) {
1392 return(EEXIST);
1393 }
1394 if ((error = ng_add_hook(node, name, &hook))) /* gives us a ref */
1395 return (error);
1396 /* Allocate the other hook and link it up */
1397 NG_ALLOC_HOOK(hook2);
1398 if (hook2 == NULL) {
1399 TRAP_ERROR();
1400 ng_destroy_hook(hook); /* XXX check ref counts so far */
1401 NG_HOOK_UNREF(hook); /* including our ref */
1402 return (ENOMEM);
1403 }
1404 hook2->hk_refs = 1; /* start with a reference for us. */
1405 hook2->hk_flags = HK_INVALID;
1406 hook2->hk_peer = hook; /* Link the two together */
1407 hook->hk_peer = hook2;
1408 NG_HOOK_REF(hook); /* Add a ref for the peer to each*/
1409 NG_HOOK_REF(hook2);
1410 hook2->hk_node = &ng_deadnode;
1411 strlcpy(NG_HOOK_NAME(hook2), name2, NG_HOOKSIZ);
1412
1413 /*
1414 * Queue the function above.
1415 * Procesing continues in that function in the lock context of
1416 * the other node.
1417 */
1418 if ((error = ng_send_fn2(node2, hook2, item, &ng_con_part2, NULL, 0,
1419 NG_NOFLAGS))) {
1420 printf("failed in ng_con_nodes(): %d\n", error);
1421 ng_destroy_hook(hook); /* also zaps peer */
1422 }
1423
1424 NG_HOOK_UNREF(hook); /* Let each hook go if it wants to */
1425 NG_HOOK_UNREF(hook2);
1426 return (error);
1427 }
1428
1429 /*
1430 * Make a peer and connect.
1431 * We assume that the local node is locked.
1432 * The new node probably doesn't need a lock until
1433 * it has a hook, because it cannot really have any work until then,
1434 * but we should think about it a bit more.
1435 *
1436 * The problem may come if the other node also fires up
1437 * some hardware or a timer or some other source of activation,
1438 * also it may already get a command msg via it's ID.
1439 *
1440 * We could use the same method as ng_con_nodes() but we'd have
1441 * to add ability to remove the node when failing. (Not hard, just
1442 * make arg1 point to the node to remove).
1443 * Unless of course we just ignore failure to connect and leave
1444 * an unconnected node?
1445 */
1446 static int
1447 ng_mkpeer(node_p node, const char *name, const char *name2, char *type)
1448 {
1449 node_p node2;
1450 hook_p hook1, hook2;
1451 int error;
1452
1453 if ((error = ng_make_node(type, &node2))) {
1454 return (error);
1455 }
1456
1457 if ((error = ng_add_hook(node, name, &hook1))) { /* gives us a ref */
1458 ng_rmnode(node2, NULL, NULL, 0);
1459 return (error);
1460 }
1461
1462 if ((error = ng_add_hook(node2, name2, &hook2))) {
1463 ng_rmnode(node2, NULL, NULL, 0);
1464 ng_destroy_hook(hook1);
1465 NG_HOOK_UNREF(hook1);
1466 return (error);
1467 }
1468
1469 /*
1470 * Actually link the two hooks together.
1471 */
1472 hook1->hk_peer = hook2;
1473 hook2->hk_peer = hook1;
1474
1475 /* Each hook is referenced by the other */
1476 NG_HOOK_REF(hook1);
1477 NG_HOOK_REF(hook2);
1478
1479 /* Give each node the opportunity to veto the pending connection */
1480 if (hook1->hk_node->nd_type->connect) {
1481 error = (*hook1->hk_node->nd_type->connect) (hook1);
1482 }
1483
1484 if ((error == 0) && hook2->hk_node->nd_type->connect) {
1485 error = (*hook2->hk_node->nd_type->connect) (hook2);
1486
1487 }
1488
1489 /*
1490 * drop the references we were holding on the two hooks.
1491 */
1492 if (error) {
1493 ng_destroy_hook(hook2); /* also zaps hook1 */
1494 ng_rmnode(node2, NULL, NULL, 0);
1495 } else {
1496 /* As a last act, allow the hooks to be used */
1497 hook1->hk_flags &= ~HK_INVALID;
1498 hook2->hk_flags &= ~HK_INVALID;
1499 }
1500 NG_HOOK_UNREF(hook1);
1501 NG_HOOK_UNREF(hook2);
1502 return (error);
1503 }
1504
1505 /************************************************************************
1506 Utility routines to send self messages
1507 ************************************************************************/
1508
1509 /* Shut this node down as soon as everyone is clear of it */
1510 /* Should add arg "immediately" to jump the queue */
1511 int
1512 ng_rmnode_self(node_p node)
1513 {
1514 int error;
1515
1516 if (node == &ng_deadnode)
1517 return (0);
1518 node->nd_flags |= NGF_INVALID;
1519 if (node->nd_flags & NGF_CLOSING)
1520 return (0);
1521
1522 error = ng_send_fn(node, NULL, &ng_rmnode, NULL, 0);
1523 return (error);
1524 }
1525
1526 static void
1527 ng_rmhook_part2(node_p node, hook_p hook, void *arg1, int arg2)
1528 {
1529 ng_destroy_hook(hook);
1530 return ;
1531 }
1532
1533 int
1534 ng_rmhook_self(hook_p hook)
1535 {
1536 int error;
1537 node_p node = NG_HOOK_NODE(hook);
1538
1539 if (node == &ng_deadnode)
1540 return (0);
1541
1542 error = ng_send_fn(node, hook, &ng_rmhook_part2, NULL, 0);
1543 return (error);
1544 }
1545
1546 /***********************************************************************
1547 * Parse and verify a string of the form: <NODE:><PATH>
1548 *
1549 * Such a string can refer to a specific node or a specific hook
1550 * on a specific node, depending on how you look at it. In the
1551 * latter case, the PATH component must not end in a dot.
1552 *
1553 * Both <NODE:> and <PATH> are optional. The <PATH> is a string
1554 * of hook names separated by dots. This breaks out the original
1555 * string, setting *nodep to "NODE" (or NULL if none) and *pathp
1556 * to "PATH" (or NULL if degenerate). Also, *hookp will point to
1557 * the final hook component of <PATH>, if any, otherwise NULL.
1558 *
1559 * This returns -1 if the path is malformed. The char ** are optional.
1560 ***********************************************************************/
1561 int
1562 ng_path_parse(char *addr, char **nodep, char **pathp, char **hookp)
1563 {
1564 char *node, *path, *hook;
1565 int k;
1566
1567 /*
1568 * Extract absolute NODE, if any
1569 */
1570 for (path = addr; *path && *path != ':'; path++);
1571 if (*path) {
1572 node = addr; /* Here's the NODE */
1573 *path++ = '\0'; /* Here's the PATH */
1574
1575 /* Node name must not be empty */
1576 if (!*node)
1577 return -1;
1578
1579 /* A name of "." is OK; otherwise '.' not allowed */
1580 if (strcmp(node, ".") != 0) {
1581 for (k = 0; node[k]; k++)
1582 if (node[k] == '.')
1583 return -1;
1584 }
1585 } else {
1586 node = NULL; /* No absolute NODE */
1587 path = addr; /* Here's the PATH */
1588 }
1589
1590 /* Snoop for illegal characters in PATH */
1591 for (k = 0; path[k]; k++)
1592 if (path[k] == ':')
1593 return -1;
1594
1595 /* Check for no repeated dots in PATH */
1596 for (k = 0; path[k]; k++)
1597 if (path[k] == '.' && path[k + 1] == '.')
1598 return -1;
1599
1600 /* Remove extra (degenerate) dots from beginning or end of PATH */
1601 if (path[0] == '.')
1602 path++;
1603 if (*path && path[strlen(path) - 1] == '.')
1604 path[strlen(path) - 1] = 0;
1605
1606 /* If PATH has a dot, then we're not talking about a hook */
1607 if (*path) {
1608 for (hook = path, k = 0; path[k]; k++)
1609 if (path[k] == '.') {
1610 hook = NULL;
1611 break;
1612 }
1613 } else
1614 path = hook = NULL;
1615
1616 /* Done */
1617 if (nodep)
1618 *nodep = node;
1619 if (pathp)
1620 *pathp = path;
1621 if (hookp)
1622 *hookp = hook;
1623 return (0);
1624 }
1625
1626 /*
1627 * Given a path, which may be absolute or relative, and a starting node,
1628 * return the destination node.
1629 */
1630 int
1631 ng_path2noderef(node_p here, const char *address,
1632 node_p *destp, hook_p *lasthook)
1633 {
1634 char fullpath[NG_PATHSIZ];
1635 char *nodename, *path, pbuf[2];
1636 node_p node, oldnode;
1637 char *cp;
1638 hook_p hook = NULL;
1639
1640 /* Initialize */
1641 if (destp == NULL) {
1642 TRAP_ERROR();
1643 return EINVAL;
1644 }
1645 *destp = NULL;
1646
1647 /* Make a writable copy of address for ng_path_parse() */
1648 strncpy(fullpath, address, sizeof(fullpath) - 1);
1649 fullpath[sizeof(fullpath) - 1] = '\0';
1650
1651 /* Parse out node and sequence of hooks */
1652 if (ng_path_parse(fullpath, &nodename, &path, NULL) < 0) {
1653 TRAP_ERROR();
1654 return EINVAL;
1655 }
1656 if (path == NULL) {
1657 pbuf[0] = '.'; /* Needs to be writable */
1658 pbuf[1] = '\0';
1659 path = pbuf;
1660 }
1661
1662 /*
1663 * For an absolute address, jump to the starting node.
1664 * Note that this holds a reference on the node for us.
1665 * Don't forget to drop the reference if we don't need it.
1666 */
1667 if (nodename) {
1668 node = ng_name2noderef(here, nodename);
1669 if (node == NULL) {
1670 TRAP_ERROR();
1671 return (ENOENT);
1672 }
1673 } else {
1674 if (here == NULL) {
1675 TRAP_ERROR();
1676 return (EINVAL);
1677 }
1678 node = here;
1679 NG_NODE_REF(node);
1680 }
1681
1682 /*
1683 * Now follow the sequence of hooks
1684 * XXX
1685 * We actually cannot guarantee that the sequence
1686 * is not being demolished as we crawl along it
1687 * without extra-ordinary locking etc.
1688 * So this is a bit dodgy to say the least.
1689 * We can probably hold up some things by holding
1690 * the nodelist mutex for the time of this
1691 * crawl if we wanted.. At least that way we wouldn't have to
1692 * worry about the nodes disappearing, but the hooks would still
1693 * be a problem.
1694 */
1695 for (cp = path; node != NULL && *cp != '\0'; ) {
1696 char *segment;
1697
1698 /*
1699 * Break out the next path segment. Replace the dot we just
1700 * found with a NUL; "cp" points to the next segment (or the
1701 * NUL at the end).
1702 */
1703 for (segment = cp; *cp != '\0'; cp++) {
1704 if (*cp == '.') {
1705 *cp++ = '\0';
1706 break;
1707 }
1708 }
1709
1710 /* Empty segment */
1711 if (*segment == '\0')
1712 continue;
1713
1714 /* We have a segment, so look for a hook by that name */
1715 hook = ng_findhook(node, segment);
1716
1717 /* Can't get there from here... */
1718 if (hook == NULL
1719 || NG_HOOK_PEER(hook) == NULL
1720 || NG_HOOK_NOT_VALID(hook)
1721 || NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook))) {
1722 TRAP_ERROR();
1723 NG_NODE_UNREF(node);
1724 #if 0
1725 printf("hooknotvalid %s %s %d %d %d %d ",
1726 path,
1727 segment,
1728 hook == NULL,
1729 NG_HOOK_PEER(hook) == NULL,
1730 NG_HOOK_NOT_VALID(hook),
1731 NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook)));
1732 #endif
1733 return (ENOENT);
1734 }
1735
1736 /*
1737 * Hop on over to the next node
1738 * XXX
1739 * Big race conditions here as hooks and nodes go away
1740 * *** Idea.. store an ng_ID_t in each hook and use that
1741 * instead of the direct hook in this crawl?
1742 */
1743 oldnode = node;
1744 if ((node = NG_PEER_NODE(hook)))
1745 NG_NODE_REF(node); /* XXX RACE */
1746 NG_NODE_UNREF(oldnode); /* XXX another race */
1747 if (NG_NODE_NOT_VALID(node)) {
1748 NG_NODE_UNREF(node); /* XXX more races */
1749 node = NULL;
1750 }
1751 }
1752
1753 /* If node somehow missing, fail here (probably this is not needed) */
1754 if (node == NULL) {
1755 TRAP_ERROR();
1756 return (ENXIO);
1757 }
1758
1759 /* Done */
1760 *destp = node;
1761 if (lasthook != NULL)
1762 *lasthook = (hook ? NG_HOOK_PEER(hook) : NULL);
1763 return (0);
1764 }
1765
1766 /***************************************************************\
1767 * Input queue handling.
1768 * All activities are submitted to the node via the input queue
1769 * which implements a multiple-reader/single-writer gate.
1770 * Items which cannot be handled immediately are queued.
1771 *
1772 * read-write queue locking inline functions *
1773 \***************************************************************/
1774
1775 static __inline item_p ng_dequeue(struct ng_queue * ngq, int *rw);
1776 static __inline item_p ng_acquire_read(struct ng_queue * ngq,
1777 item_p item);
1778 static __inline item_p ng_acquire_write(struct ng_queue * ngq,
1779 item_p item);
1780 static __inline void ng_leave_read(struct ng_queue * ngq);
1781 static __inline void ng_leave_write(struct ng_queue * ngq);
1782 static __inline void ng_queue_rw(struct ng_queue * ngq,
1783 item_p item, int rw);
1784
1785 /*
1786 * Definition of the bits fields in the ng_queue flag word.
1787 * Defined here rather than in netgraph.h because no-one should fiddle
1788 * with them.
1789 *
1790 * The ordering here may be important! don't shuffle these.
1791 */
1792 /*-
1793 Safety Barrier--------+ (adjustable to suit taste) (not used yet)
1794 |
1795 V
1796 +-------+-------+-------+-------+-------+-------+-------+-------+
1797 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
1798 | |A|c|t|i|v|e| |R|e|a|d|e|r| |C|o|u|n|t| | | | | | | | | |P|A|
1799 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |O|W|
1800 +-------+-------+-------+-------+-------+-------+-------+-------+
1801 \___________________________ ____________________________/ | |
1802 V | |
1803 [active reader count] | |
1804 | |
1805 Operation Pending -------------------------------+ |
1806 |
1807 Active Writer ---------------------------------------+
1808
1809 Node queue has such semantics:
1810 - All flags modifications are atomic.
1811 - Reader count can be incremented only if there is no writer or pending flags.
1812 As soon as this can't be done with single operation, it is implemented with
1813 spin loop and atomic_cmpset().
1814 - Writer flag can be set only if there is no any bits set.
1815 It is implemented with atomic_cmpset().
1816 - Pending flag can be set any time, but to avoid collision on queue processing
1817 all queue fields are protected by the mutex.
1818 - Queue processing thread reads queue holding the mutex, but releases it while
1819 processing. When queue is empty pending flag is removed.
1820 */
1821
1822 #define WRITER_ACTIVE 0x00000001
1823 #define OP_PENDING 0x00000002
1824 #define READER_INCREMENT 0x00000004
1825 #define READER_MASK 0xfffffffc /* Not valid if WRITER_ACTIVE is set */
1826 #define SAFETY_BARRIER 0x00100000 /* 128K items queued should be enough */
1827
1828 /* Defines of more elaborate states on the queue */
1829 /* Mask of bits a new read cares about */
1830 #define NGQ_RMASK (WRITER_ACTIVE|OP_PENDING)
1831
1832 /* Mask of bits a new write cares about */
1833 #define NGQ_WMASK (NGQ_RMASK|READER_MASK)
1834
1835 /* Test to decide if there is something on the queue. */
1836 #define QUEUE_ACTIVE(QP) ((QP)->q_flags & OP_PENDING)
1837
1838 /* How to decide what the next queued item is. */
1839 #define HEAD_IS_READER(QP) NGI_QUEUED_READER((QP)->queue)
1840 #define HEAD_IS_WRITER(QP) NGI_QUEUED_WRITER((QP)->queue) /* notused */
1841
1842 /* Read the status to decide if the next item on the queue can now run. */
1843 #define QUEUED_READER_CAN_PROCEED(QP) \
1844 (((QP)->q_flags & (NGQ_RMASK & ~OP_PENDING)) == 0)
1845 #define QUEUED_WRITER_CAN_PROCEED(QP) \
1846 (((QP)->q_flags & (NGQ_WMASK & ~OP_PENDING)) == 0)
1847
1848 /* Is there a chance of getting ANY work off the queue? */
1849 #define NEXT_QUEUED_ITEM_CAN_PROCEED(QP) \
1850 ((HEAD_IS_READER(QP)) ? QUEUED_READER_CAN_PROCEED(QP) : \
1851 QUEUED_WRITER_CAN_PROCEED(QP))
1852
1853
1854 #define NGQRW_R 0
1855 #define NGQRW_W 1
1856
1857 /*
1858 * Taking into account the current state of the queue and node, possibly take
1859 * the next entry off the queue and return it. Return NULL if there was
1860 * nothing we could return, either because there really was nothing there, or
1861 * because the node was in a state where it cannot yet process the next item
1862 * on the queue.
1863 */
1864 static __inline item_p
1865 ng_dequeue(struct ng_queue *ngq, int *rw)
1866 {
1867 item_p item;
1868
1869 /* This MUST be called with the mutex held. */
1870 mtx_assert(&ngq->q_mtx, MA_OWNED);
1871
1872 /* If there is nothing queued, then just return. */
1873 if (!QUEUE_ACTIVE(ngq)) {
1874 CTR4(KTR_NET, "%20s: node [%x] (%p) queue empty; "
1875 "queue flags 0x%lx", __func__,
1876 ngq->q_node->nd_ID, ngq->q_node, ngq->q_flags);
1877 return (NULL);
1878 }
1879
1880 /*
1881 * From here, we can assume there is a head item.
1882 * We need to find out what it is and if it can be dequeued, given
1883 * the current state of the node.
1884 */
1885 if (HEAD_IS_READER(ngq)) {
1886 while (1) {
1887 long t = ngq->q_flags;
1888 if (t & WRITER_ACTIVE) {
1889 /* There is writer, reader can't proceed. */
1890 CTR4(KTR_NET, "%20s: node [%x] (%p) queued reader "
1891 "can't proceed; queue flags 0x%lx", __func__,
1892 ngq->q_node->nd_ID, ngq->q_node, t);
1893 return (NULL);
1894 }
1895 if (atomic_cmpset_acq_long(&ngq->q_flags, t,
1896 t + READER_INCREMENT))
1897 break;
1898 cpu_spinwait();
1899 }
1900 /* We have got reader lock for the node. */
1901 *rw = NGQRW_R;
1902 } else if (atomic_cmpset_acq_long(&ngq->q_flags, OP_PENDING,
1903 OP_PENDING + WRITER_ACTIVE)) {
1904 /* We have got writer lock for the node. */
1905 *rw = NGQRW_W;
1906 } else {
1907 /* There is somebody other, writer can't proceed. */
1908 CTR4(KTR_NET, "%20s: node [%x] (%p) queued writer "
1909 "can't proceed; queue flags 0x%lx", __func__,
1910 ngq->q_node->nd_ID, ngq->q_node, ngq->q_flags);
1911 return (NULL);
1912 }
1913
1914 /*
1915 * Now we dequeue the request (whatever it may be) and correct the
1916 * pending flags and the next and last pointers.
1917 */
1918 item = ngq->queue;
1919 ngq->queue = item->el_next;
1920 if (ngq->last == &(item->el_next)) {
1921 ngq->last = &(ngq->queue);
1922 atomic_clear_long(&ngq->q_flags, OP_PENDING);
1923 }
1924 CTR6(KTR_NET, "%20s: node [%x] (%p) returning item %p as %s; "
1925 "queue flags 0x%lx", __func__,
1926 ngq->q_node->nd_ID, ngq->q_node, item, *rw ? "WRITER" : "READER" ,
1927 ngq->q_flags);
1928 return (item);
1929 }
1930
1931 /*
1932 * Queue a packet to be picked up later by someone else.
1933 * If the queue could be run now, add node to the queue handler's worklist.
1934 */
1935 static __inline void
1936 ng_queue_rw(struct ng_queue * ngq, item_p item, int rw)
1937 {
1938 if (rw == NGQRW_W)
1939 NGI_SET_WRITER(item);
1940 else
1941 NGI_SET_READER(item);
1942 item->el_next = NULL; /* maybe not needed */
1943
1944 NG_QUEUE_LOCK(ngq);
1945 /* Set OP_PENDING flag and enqueue the item. */
1946 atomic_set_long(&ngq->q_flags, OP_PENDING);
1947 *ngq->last = item;
1948 ngq->last = &(item->el_next);
1949
1950 CTR5(KTR_NET, "%20s: node [%x] (%p) queued item %p as %s", __func__,
1951 ngq->q_node->nd_ID, ngq->q_node, item, rw ? "WRITER" : "READER" );
1952
1953 /*
1954 * We can take the worklist lock with the node locked
1955 * BUT NOT THE REVERSE!
1956 */
1957 if (NEXT_QUEUED_ITEM_CAN_PROCEED(ngq))
1958 ng_worklist_add(ngq->q_node);
1959 NG_QUEUE_UNLOCK(ngq);
1960 }
1961
1962 /* Acquire reader lock on node. If node is busy, queue the packet. */
1963 static __inline item_p
1964 ng_acquire_read(struct ng_queue *ngq, item_p item)
1965 {
1966 KASSERT(ngq != &ng_deadnode.nd_input_queue,
1967 ("%s: working on deadnode", __func__));
1968
1969 /* Reader needs node without writer and pending items. */
1970 while (1) {
1971 long t = ngq->q_flags;
1972 if (t & NGQ_RMASK)
1973 break; /* Node is not ready for reader. */
1974 if (atomic_cmpset_acq_long(&ngq->q_flags, t, t + READER_INCREMENT)) {
1975 /* Successfully grabbed node */
1976 CTR4(KTR_NET, "%20s: node [%x] (%p) acquired item %p",
1977 __func__, ngq->q_node->nd_ID, ngq->q_node, item);
1978 return (item);
1979 }
1980 cpu_spinwait();
1981 };
1982
1983 /* Queue the request for later. */
1984 ng_queue_rw(ngq, item, NGQRW_R);
1985
1986 return (NULL);
1987 }
1988
1989 /* Acquire writer lock on node. If node is busy, queue the packet. */
1990 static __inline item_p
1991 ng_acquire_write(struct ng_queue *ngq, item_p item)
1992 {
1993 KASSERT(ngq != &ng_deadnode.nd_input_queue,
1994 ("%s: working on deadnode", __func__));
1995
1996 /* Writer needs completely idle node. */
1997 if (atomic_cmpset_acq_long(&ngq->q_flags, 0, WRITER_ACTIVE)) {
1998 /* Successfully grabbed node */
1999 CTR4(KTR_NET, "%20s: node [%x] (%p) acquired item %p",
2000 __func__, ngq->q_node->nd_ID, ngq->q_node, item);
2001 return (item);
2002 }
2003
2004 /* Queue the request for later. */
2005 ng_queue_rw(ngq, item, NGQRW_W);
2006
2007 return (NULL);
2008 }
2009
2010 #if 0
2011 static __inline item_p
2012 ng_upgrade_write(struct ng_queue *ngq, item_p item)
2013 {
2014 KASSERT(ngq != &ng_deadnode.nd_input_queue,
2015 ("%s: working on deadnode", __func__));
2016
2017 NGI_SET_WRITER(item);
2018
2019 mtx_lock_spin(&(ngq->q_mtx));
2020
2021 /*
2022 * There will never be no readers as we are there ourselves.
2023 * Set the WRITER_ACTIVE flags ASAP to block out fast track readers.
2024 * The caller we are running from will call ng_leave_read()
2025 * soon, so we must account for that. We must leave again with the
2026 * READER lock. If we find other readers, then
2027 * queue the request for later. However "later" may be rignt now
2028 * if there are no readers. We don't really care if there are queued
2029 * items as we will bypass them anyhow.
2030 */
2031 atomic_add_long(&ngq->q_flags, WRITER_ACTIVE - READER_INCREMENT);
2032 if (ngq->q_flags & (NGQ_WMASK & ~OP_PENDING) == WRITER_ACTIVE) {
2033 mtx_unlock_spin(&(ngq->q_mtx));
2034
2035 /* It's just us, act on the item. */
2036 /* will NOT drop writer lock when done */
2037 ng_apply_item(node, item, 0);
2038
2039 /*
2040 * Having acted on the item, atomically
2041 * down grade back to READER and finish up
2042 */
2043 atomic_add_long(&ngq->q_flags,
2044 READER_INCREMENT - WRITER_ACTIVE);
2045
2046 /* Our caller will call ng_leave_read() */
2047 return;
2048 }
2049 /*
2050 * It's not just us active, so queue us AT THE HEAD.
2051 * "Why?" I hear you ask.
2052 * Put us at the head of the queue as we've already been
2053 * through it once. If there is nothing else waiting,
2054 * set the correct flags.
2055 */
2056 if ((item->el_next = ngq->queue) == NULL) {
2057 /*
2058 * Set up the "last" pointer.
2059 * We are the only (and thus last) item
2060 */
2061 ngq->last = &(item->el_next);
2062
2063 /* We've gone from, 0 to 1 item in the queue */
2064 atomic_set_long(&ngq->q_flags, OP_PENDING);
2065
2066 CTR3(KTR_NET, "%20s: node [%x] (%p) set OP_PENDING", __func__,
2067 ngq->q_node->nd_ID, ngq->q_node);
2068 };
2069 ngq->queue = item;
2070 CTR5(KTR_NET, "%20s: node [%x] (%p) requeued item %p as WRITER",
2071 __func__, ngq->q_node->nd_ID, ngq->q_node, item );
2072
2073 /* Reverse what we did above. That downgrades us back to reader */
2074 atomic_add_long(&ngq->q_flags, READER_INCREMENT - WRITER_ACTIVE);
2075 if (QUEUE_ACTIVE(ngq) && NEXT_QUEUED_ITEM_CAN_PROCEED(ngq))
2076 ng_worklist_add(ngq->q_node);
2077 mtx_unlock_spin(&(ngq->q_mtx));
2078
2079 return;
2080 }
2081
2082 #endif
2083
2084 /* Release reader lock. */
2085 static __inline void
2086 ng_leave_read(struct ng_queue *ngq)
2087 {
2088 atomic_subtract_rel_long(&ngq->q_flags, READER_INCREMENT);
2089 }
2090
2091 /* Release writer lock. */
2092 static __inline void
2093 ng_leave_write(struct ng_queue *ngq)
2094 {
2095 atomic_clear_rel_long(&ngq->q_flags, WRITER_ACTIVE);
2096 }
2097
2098 /* Purge node queue. Called on node shutdown. */
2099 static void
2100 ng_flush_input_queue(struct ng_queue * ngq)
2101 {
2102 item_p item;
2103
2104 NG_QUEUE_LOCK(ngq);
2105 while (ngq->queue) {
2106 item = ngq->queue;
2107 ngq->queue = item->el_next;
2108 if (ngq->last == &(item->el_next)) {
2109 ngq->last = &(ngq->queue);
2110 atomic_clear_long(&ngq->q_flags, OP_PENDING);
2111 }
2112 NG_QUEUE_UNLOCK(ngq);
2113
2114 /* If the item is supplying a callback, call it with an error */
2115 if (item->apply != NULL) {
2116 if (item->depth == 1)
2117 item->apply->error = ENOENT;
2118 if (refcount_release(&item->apply->refs)) {
2119 (*item->apply->apply)(item->apply->context,
2120 item->apply->error);
2121 }
2122 }
2123 NG_FREE_ITEM(item);
2124 NG_QUEUE_LOCK(ngq);
2125 }
2126 NG_QUEUE_UNLOCK(ngq);
2127 }
2128
2129 /***********************************************************************
2130 * Externally visible method for sending or queueing messages or data.
2131 ***********************************************************************/
2132
2133 /*
2134 * The module code should have filled out the item correctly by this stage:
2135 * Common:
2136 * reference to destination node.
2137 * Reference to destination rcv hook if relevant.
2138 * apply pointer must be or NULL or reference valid struct ng_apply_info.
2139 * Data:
2140 * pointer to mbuf
2141 * Control_Message:
2142 * pointer to msg.
2143 * ID of original sender node. (return address)
2144 * Function:
2145 * Function pointer
2146 * void * argument
2147 * integer argument
2148 *
2149 * The nodes have several routines and macros to help with this task:
2150 */
2151
2152 int
2153 ng_snd_item(item_p item, int flags)
2154 {
2155 hook_p hook;
2156 node_p node;
2157 int queue, rw;
2158 struct ng_queue *ngq;
2159 int error = 0;
2160
2161 /* We are sending item, so it must be present! */
2162 KASSERT(item != NULL, ("ng_snd_item: item is NULL"));
2163
2164 #ifdef NETGRAPH_DEBUG
2165 _ngi_check(item, __FILE__, __LINE__);
2166 #endif
2167
2168 /* Item was sent once more, postpone apply() call. */
2169 if (item->apply)
2170 refcount_acquire(&item->apply->refs);
2171
2172 node = NGI_NODE(item);
2173 /* Node is never optional. */
2174 KASSERT(node != NULL, ("ng_snd_item: node is NULL"));
2175
2176 hook = NGI_HOOK(item);
2177 /* Valid hook and mbuf are mandatory for data. */
2178 if ((item->el_flags & NGQF_TYPE) == NGQF_DATA) {
2179 KASSERT(hook != NULL, ("ng_snd_item: hook for data is NULL"));
2180 if (NGI_M(item) == NULL)
2181 ERROUT(EINVAL);
2182 CHECK_DATA_MBUF(NGI_M(item));
2183 }
2184
2185 /*
2186 * If the item or the node specifies single threading, force
2187 * writer semantics. Similarly, the node may say one hook always
2188 * produces writers. These are overrides.
2189 */
2190 if (((item->el_flags & NGQF_RW) == NGQF_WRITER) ||
2191 (node->nd_flags & NGF_FORCE_WRITER) ||
2192 (hook && (hook->hk_flags & HK_FORCE_WRITER))) {
2193 rw = NGQRW_W;
2194 } else {
2195 rw = NGQRW_R;
2196 }
2197
2198 /*
2199 * If sender or receiver requests queued delivery or stack usage
2200 * level is dangerous - enqueue message.
2201 */
2202 if ((flags & NG_QUEUE) || (hook && (hook->hk_flags & HK_QUEUE))) {
2203 queue = 1;
2204 } else {
2205 queue = 0;
2206 #ifdef GET_STACK_USAGE
2207 /*
2208 * Most of netgraph nodes have small stack consumption and
2209 * for them 25% of free stack space is more than enough.
2210 * Nodes/hooks with higher stack usage should be marked as
2211 * HI_STACK. For them 50% of stack will be guaranteed then.
2212 * XXX: Values 25% and 50% are completely empirical.
2213 */
2214 size_t st, su, sl;
2215 GET_STACK_USAGE(st, su);
2216 sl = st - su;
2217 if ((sl * 4 < st) ||
2218 ((sl * 2 < st) && ((node->nd_flags & NGF_HI_STACK) ||
2219 (hook && (hook->hk_flags & HK_HI_STACK))))) {
2220 queue = 1;
2221 }
2222 #endif
2223 }
2224
2225 ngq = &node->nd_input_queue;
2226 if (queue) {
2227 item->depth = 1;
2228 /* Put it on the queue for that node*/
2229 ng_queue_rw(ngq, item, rw);
2230 return ((flags & NG_PROGRESS) ? EINPROGRESS : 0);
2231 }
2232
2233 /*
2234 * We already decided how we will be queueud or treated.
2235 * Try get the appropriate operating permission.
2236 */
2237 if (rw == NGQRW_R)
2238 item = ng_acquire_read(ngq, item);
2239 else
2240 item = ng_acquire_write(ngq, item);
2241
2242 /* Item was queued while trying to get permission. */
2243 if (item == NULL)
2244 return ((flags & NG_PROGRESS) ? EINPROGRESS : 0);
2245
2246 NGI_GET_NODE(item, node); /* zaps stored node */
2247
2248 item->depth++;
2249 error = ng_apply_item(node, item, rw); /* drops r/w lock when done */
2250
2251 /* If something is waiting on queue and ready, schedule it. */
2252 if (QUEUE_ACTIVE(ngq)) {
2253 NG_QUEUE_LOCK(ngq);
2254 if (QUEUE_ACTIVE(ngq) && NEXT_QUEUED_ITEM_CAN_PROCEED(ngq))
2255 ng_worklist_add(ngq->q_node);
2256 NG_QUEUE_UNLOCK(ngq);
2257 }
2258
2259 /*
2260 * Node may go away as soon as we remove the reference.
2261 * Whatever we do, DO NOT access the node again!
2262 */
2263 NG_NODE_UNREF(node);
2264
2265 return (error);
2266
2267 done:
2268 /* If was not sent, apply callback here. */
2269 if (item->apply != NULL) {
2270 if (item->depth == 0 && error != 0)
2271 item->apply->error = error;
2272 if (refcount_release(&item->apply->refs)) {
2273 (*item->apply->apply)(item->apply->context,
2274 item->apply->error);
2275 }
2276 }
2277
2278 NG_FREE_ITEM(item);
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 * If there is apply pointer and we own the last reference, call apply().
2287 */
2288 static int
2289 ng_apply_item(node_p node, item_p item, int rw)
2290 {
2291 hook_p hook;
2292 ng_rcvdata_t *rcvdata;
2293 ng_rcvmsg_t *rcvmsg;
2294 struct ng_apply_info *apply;
2295 int error = 0, depth;
2296
2297 /* Node and item are never optional. */
2298 KASSERT(node != NULL, ("ng_apply_item: node is NULL"));
2299 KASSERT(item != NULL, ("ng_apply_item: item is NULL"));
2300
2301 NGI_GET_HOOK(item, hook); /* clears stored hook */
2302 #ifdef NETGRAPH_DEBUG
2303 _ngi_check(item, __FILE__, __LINE__);
2304 #endif
2305
2306 apply = item->apply;
2307 depth = item->depth;
2308
2309 switch (item->el_flags & NGQF_TYPE) {
2310 case NGQF_DATA:
2311 /*
2312 * Check things are still ok as when we were queued.
2313 */
2314 KASSERT(hook != NULL, ("ng_apply_item: hook for data is NULL"));
2315 if (NG_HOOK_NOT_VALID(hook) ||
2316 NG_NODE_NOT_VALID(node)) {
2317 error = EIO;
2318 NG_FREE_ITEM(item);
2319 break;
2320 }
2321 /*
2322 * If no receive method, just silently drop it.
2323 * Give preference to the hook over-ride method
2324 */
2325 if ((!(rcvdata = hook->hk_rcvdata))
2326 && (!(rcvdata = NG_HOOK_NODE(hook)->nd_type->rcvdata))) {
2327 error = 0;
2328 NG_FREE_ITEM(item);
2329 break;
2330 }
2331 error = (*rcvdata)(hook, item);
2332 break;
2333 case NGQF_MESG:
2334 if (hook && NG_HOOK_NOT_VALID(hook)) {
2335 /*
2336 * The hook has been zapped then we can't use it.
2337 * Immediately drop its reference.
2338 * The message may not need it.
2339 */
2340 NG_HOOK_UNREF(hook);
2341 hook = NULL;
2342 }
2343 /*
2344 * Similarly, if the node is a zombie there is
2345 * nothing we can do with it, drop everything.
2346 */
2347 if (NG_NODE_NOT_VALID(node)) {
2348 TRAP_ERROR();
2349 error = EINVAL;
2350 NG_FREE_ITEM(item);
2351 break;
2352 }
2353 /*
2354 * Call the appropriate message handler for the object.
2355 * It is up to the message handler to free the message.
2356 * If it's a generic message, handle it generically,
2357 * otherwise call the type's message handler (if it exists).
2358 * XXX (race). Remember that a queued message may
2359 * reference a node or hook that has just been
2360 * invalidated. It will exist as the queue code
2361 * is holding a reference, but..
2362 */
2363 if ((NGI_MSG(item)->header.typecookie == NGM_GENERIC_COOKIE) &&
2364 ((NGI_MSG(item)->header.flags & NGF_RESP) == 0)) {
2365 error = ng_generic_msg(node, item, hook);
2366 break;
2367 }
2368 if (((!hook) || (!(rcvmsg = hook->hk_rcvmsg))) &&
2369 (!(rcvmsg = node->nd_type->rcvmsg))) {
2370 TRAP_ERROR();
2371 error = 0;
2372 NG_FREE_ITEM(item);
2373 break;
2374 }
2375 error = (*rcvmsg)(node, item, hook);
2376 break;
2377 case NGQF_FN:
2378 case NGQF_FN2:
2379 /*
2380 * We have to implicitly trust the hook,
2381 * as some of these are used for system purposes
2382 * where the hook is invalid. In the case of
2383 * the shutdown message we allow it to hit
2384 * even if the node is invalid.
2385 */
2386 if ((NG_NODE_NOT_VALID(node))
2387 && (NGI_FN(item) != &ng_rmnode)) {
2388 TRAP_ERROR();
2389 error = EINVAL;
2390 NG_FREE_ITEM(item);
2391 break;
2392 }
2393 if ((item->el_flags & NGQF_TYPE) == NGQF_FN) {
2394 (*NGI_FN(item))(node, hook, NGI_ARG1(item),
2395 NGI_ARG2(item));
2396 NG_FREE_ITEM(item);
2397 } else /* it is NGQF_FN2 */
2398 error = (*NGI_FN2(item))(node, item, hook);
2399 break;
2400 }
2401 /*
2402 * We held references on some of the resources
2403 * that we took from the item. Now that we have
2404 * finished doing everything, drop those references.
2405 */
2406 if (hook)
2407 NG_HOOK_UNREF(hook);
2408
2409 if (rw == NGQRW_R)
2410 ng_leave_read(&node->nd_input_queue);
2411 else
2412 ng_leave_write(&node->nd_input_queue);
2413
2414 /* Apply callback. */
2415 if (apply != NULL) {
2416 if (depth == 1 && error != 0)
2417 apply->error = error;
2418 if (refcount_release(&apply->refs))
2419 (*apply->apply)(apply->context, apply->error);
2420 }
2421
2422 return (error);
2423 }
2424
2425 /***********************************************************************
2426 * Implement the 'generic' control messages
2427 ***********************************************************************/
2428 static int
2429 ng_generic_msg(node_p here, item_p item, hook_p lasthook)
2430 {
2431 int error = 0;
2432 struct ng_mesg *msg;
2433 struct ng_mesg *resp = NULL;
2434
2435 NGI_GET_MSG(item, msg);
2436 if (msg->header.typecookie != NGM_GENERIC_COOKIE) {
2437 TRAP_ERROR();
2438 error = EINVAL;
2439 goto out;
2440 }
2441 switch (msg->header.cmd) {
2442 case NGM_SHUTDOWN:
2443 ng_rmnode(here, NULL, NULL, 0);
2444 break;
2445 case NGM_MKPEER:
2446 {
2447 struct ngm_mkpeer *const mkp = (struct ngm_mkpeer *) msg->data;
2448
2449 if (msg->header.arglen != sizeof(*mkp)) {
2450 TRAP_ERROR();
2451 error = EINVAL;
2452 break;
2453 }
2454 mkp->type[sizeof(mkp->type) - 1] = '\0';
2455 mkp->ourhook[sizeof(mkp->ourhook) - 1] = '\0';
2456 mkp->peerhook[sizeof(mkp->peerhook) - 1] = '\0';
2457 error = ng_mkpeer(here, mkp->ourhook, mkp->peerhook, mkp->type);
2458 break;
2459 }
2460 case NGM_CONNECT:
2461 {
2462 struct ngm_connect *const con =
2463 (struct ngm_connect *) msg->data;
2464 node_p node2;
2465
2466 if (msg->header.arglen != sizeof(*con)) {
2467 TRAP_ERROR();
2468 error = EINVAL;
2469 break;
2470 }
2471 con->path[sizeof(con->path) - 1] = '\0';
2472 con->ourhook[sizeof(con->ourhook) - 1] = '\0';
2473 con->peerhook[sizeof(con->peerhook) - 1] = '\0';
2474 /* Don't forget we get a reference.. */
2475 error = ng_path2noderef(here, con->path, &node2, NULL);
2476 if (error)
2477 break;
2478 error = ng_con_nodes(item, here, con->ourhook,
2479 node2, con->peerhook);
2480 NG_NODE_UNREF(node2);
2481 break;
2482 }
2483 case NGM_NAME:
2484 {
2485 struct ngm_name *const nam = (struct ngm_name *) msg->data;
2486
2487 if (msg->header.arglen != sizeof(*nam)) {
2488 TRAP_ERROR();
2489 error = EINVAL;
2490 break;
2491 }
2492 nam->name[sizeof(nam->name) - 1] = '\0';
2493 error = ng_name_node(here, nam->name);
2494 break;
2495 }
2496 case NGM_RMHOOK:
2497 {
2498 struct ngm_rmhook *const rmh = (struct ngm_rmhook *) msg->data;
2499 hook_p hook;
2500
2501 if (msg->header.arglen != sizeof(*rmh)) {
2502 TRAP_ERROR();
2503 error = EINVAL;
2504 break;
2505 }
2506 rmh->ourhook[sizeof(rmh->ourhook) - 1] = '\0';
2507 if ((hook = ng_findhook(here, rmh->ourhook)) != NULL)
2508 ng_destroy_hook(hook);
2509 break;
2510 }
2511 case NGM_NODEINFO:
2512 {
2513 struct nodeinfo *ni;
2514
2515 NG_MKRESPONSE(resp, msg, sizeof(*ni), M_NOWAIT);
2516 if (resp == NULL) {
2517 error = ENOMEM;
2518 break;
2519 }
2520
2521 /* Fill in node info */
2522 ni = (struct nodeinfo *) resp->data;
2523 if (NG_NODE_HAS_NAME(here))
2524 strcpy(ni->name, NG_NODE_NAME(here));
2525 strcpy(ni->type, here->nd_type->name);
2526 ni->id = ng_node2ID(here);
2527 ni->hooks = here->nd_numhooks;
2528 break;
2529 }
2530 case NGM_LISTHOOKS:
2531 {
2532 const int nhooks = here->nd_numhooks;
2533 struct hooklist *hl;
2534 struct nodeinfo *ni;
2535 hook_p hook;
2536
2537 /* Get response struct */
2538 NG_MKRESPONSE(resp, msg, sizeof(*hl)
2539 + (nhooks * sizeof(struct linkinfo)), M_NOWAIT);
2540 if (resp == NULL) {
2541 error = ENOMEM;
2542 break;
2543 }
2544 hl = (struct hooklist *) resp->data;
2545 ni = &hl->nodeinfo;
2546
2547 /* Fill in node info */
2548 if (NG_NODE_HAS_NAME(here))
2549 strcpy(ni->name, NG_NODE_NAME(here));
2550 strcpy(ni->type, here->nd_type->name);
2551 ni->id = ng_node2ID(here);
2552
2553 /* Cycle through the linked list of hooks */
2554 ni->hooks = 0;
2555 LIST_FOREACH(hook, &here->nd_hooks, hk_hooks) {
2556 struct linkinfo *const link = &hl->link[ni->hooks];
2557
2558 if (ni->hooks >= nhooks) {
2559 log(LOG_ERR, "%s: number of %s changed\n",
2560 __func__, "hooks");
2561 break;
2562 }
2563 if (NG_HOOK_NOT_VALID(hook))
2564 continue;
2565 strcpy(link->ourhook, NG_HOOK_NAME(hook));
2566 strcpy(link->peerhook, NG_PEER_HOOK_NAME(hook));
2567 if (NG_PEER_NODE_NAME(hook)[0] != '\0')
2568 strcpy(link->nodeinfo.name,
2569 NG_PEER_NODE_NAME(hook));
2570 strcpy(link->nodeinfo.type,
2571 NG_PEER_NODE(hook)->nd_type->name);
2572 link->nodeinfo.id = ng_node2ID(NG_PEER_NODE(hook));
2573 link->nodeinfo.hooks = NG_PEER_NODE(hook)->nd_numhooks;
2574 ni->hooks++;
2575 }
2576 break;
2577 }
2578
2579 case NGM_LISTNAMES:
2580 case NGM_LISTNODES:
2581 {
2582 const int unnamed = (msg->header.cmd == NGM_LISTNODES);
2583 struct namelist *nl;
2584 node_p node;
2585 int num = 0, i;
2586
2587 mtx_lock(&ng_namehash_mtx);
2588 /* Count number of nodes */
2589 for (i = 0; i < NG_NAME_HASH_SIZE; i++) {
2590 LIST_FOREACH(node, &ng_name_hash[i], nd_nodes) {
2591 if (NG_NODE_IS_VALID(node) &&
2592 (unnamed || NG_NODE_HAS_NAME(node))) {
2593 num++;
2594 }
2595 }
2596 }
2597 mtx_unlock(&ng_namehash_mtx);
2598
2599 /* Get response struct */
2600 NG_MKRESPONSE(resp, msg, sizeof(*nl)
2601 + (num * sizeof(struct nodeinfo)), M_NOWAIT);
2602 if (resp == NULL) {
2603 error = ENOMEM;
2604 break;
2605 }
2606 nl = (struct namelist *) resp->data;
2607
2608 /* Cycle through the linked list of nodes */
2609 nl->numnames = 0;
2610 mtx_lock(&ng_namehash_mtx);
2611 for (i = 0; i < NG_NAME_HASH_SIZE; i++) {
2612 LIST_FOREACH(node, &ng_name_hash[i], nd_nodes) {
2613 struct nodeinfo *const np =
2614 &nl->nodeinfo[nl->numnames];
2615
2616 if (NG_NODE_NOT_VALID(node))
2617 continue;
2618 if (!unnamed && (! NG_NODE_HAS_NAME(node)))
2619 continue;
2620 if (nl->numnames >= num) {
2621 log(LOG_ERR, "%s: number of nodes changed\n",
2622 __func__);
2623 break;
2624 }
2625 if (NG_NODE_HAS_NAME(node))
2626 strcpy(np->name, NG_NODE_NAME(node));
2627 strcpy(np->type, node->nd_type->name);
2628 np->id = ng_node2ID(node);
2629 np->hooks = node->nd_numhooks;
2630 nl->numnames++;
2631 }
2632 }
2633 mtx_unlock(&ng_namehash_mtx);
2634 break;
2635 }
2636
2637 case NGM_LISTTYPES:
2638 {
2639 struct typelist *tl;
2640 struct ng_type *type;
2641 int num = 0;
2642
2643 mtx_lock(&ng_typelist_mtx);
2644 /* Count number of types */
2645 LIST_FOREACH(type, &ng_typelist, types) {
2646 num++;
2647 }
2648 mtx_unlock(&ng_typelist_mtx);
2649
2650 /* Get response struct */
2651 NG_MKRESPONSE(resp, msg, sizeof(*tl)
2652 + (num * sizeof(struct typeinfo)), M_NOWAIT);
2653 if (resp == NULL) {
2654 error = ENOMEM;
2655 break;
2656 }
2657 tl = (struct typelist *) resp->data;
2658
2659 /* Cycle through the linked list of types */
2660 tl->numtypes = 0;
2661 mtx_lock(&ng_typelist_mtx);
2662 LIST_FOREACH(type, &ng_typelist, types) {
2663 struct typeinfo *const tp = &tl->typeinfo[tl->numtypes];
2664
2665 if (tl->numtypes >= num) {
2666 log(LOG_ERR, "%s: number of %s changed\n",
2667 __func__, "types");
2668 break;
2669 }
2670 strcpy(tp->type_name, type->name);
2671 tp->numnodes = type->refs - 1; /* don't count list */
2672 tl->numtypes++;
2673 }
2674 mtx_unlock(&ng_typelist_mtx);
2675 break;
2676 }
2677
2678 case NGM_BINARY2ASCII:
2679 {
2680 int bufSize = 20 * 1024; /* XXX hard coded constant */
2681 const struct ng_parse_type *argstype;
2682 const struct ng_cmdlist *c;
2683 struct ng_mesg *binary, *ascii;
2684
2685 /* Data area must contain a valid netgraph message */
2686 binary = (struct ng_mesg *)msg->data;
2687 if (msg->header.arglen < sizeof(struct ng_mesg) ||
2688 (msg->header.arglen - sizeof(struct ng_mesg) <
2689 binary->header.arglen)) {
2690 TRAP_ERROR();
2691 error = EINVAL;
2692 break;
2693 }
2694
2695 /* Get a response message with lots of room */
2696 NG_MKRESPONSE(resp, msg, sizeof(*ascii) + bufSize, M_NOWAIT);
2697 if (resp == NULL) {
2698 error = ENOMEM;
2699 break;
2700 }
2701 ascii = (struct ng_mesg *)resp->data;
2702
2703 /* Copy binary message header to response message payload */
2704 bcopy(binary, ascii, sizeof(*binary));
2705
2706 /* Find command by matching typecookie and command number */
2707 for (c = here->nd_type->cmdlist;
2708 c != NULL && c->name != NULL; c++) {
2709 if (binary->header.typecookie == c->cookie
2710 && binary->header.cmd == c->cmd)
2711 break;
2712 }
2713 if (c == NULL || c->name == NULL) {
2714 for (c = ng_generic_cmds; c->name != NULL; c++) {
2715 if (binary->header.typecookie == c->cookie
2716 && binary->header.cmd == c->cmd)
2717 break;
2718 }
2719 if (c->name == NULL) {
2720 NG_FREE_MSG(resp);
2721 error = ENOSYS;
2722 break;
2723 }
2724 }
2725
2726 /* Convert command name to ASCII */
2727 snprintf(ascii->header.cmdstr, sizeof(ascii->header.cmdstr),
2728 "%s", c->name);
2729
2730 /* Convert command arguments to ASCII */
2731 argstype = (binary->header.flags & NGF_RESP) ?
2732 c->respType : c->mesgType;
2733 if (argstype == NULL) {
2734 *ascii->data = '\0';
2735 } else {
2736 if ((error = ng_unparse(argstype,
2737 (u_char *)binary->data,
2738 ascii->data, bufSize)) != 0) {
2739 NG_FREE_MSG(resp);
2740 break;
2741 }
2742 }
2743
2744 /* Return the result as struct ng_mesg plus ASCII string */
2745 bufSize = strlen(ascii->data) + 1;
2746 ascii->header.arglen = bufSize;
2747 resp->header.arglen = sizeof(*ascii) + bufSize;
2748 break;
2749 }
2750
2751 case NGM_ASCII2BINARY:
2752 {
2753 int bufSize = 2000; /* XXX hard coded constant */
2754 const struct ng_cmdlist *c;
2755 const struct ng_parse_type *argstype;
2756 struct ng_mesg *ascii, *binary;
2757 int off = 0;
2758
2759 /* Data area must contain at least a struct ng_mesg + '\0' */
2760 ascii = (struct ng_mesg *)msg->data;
2761 if ((msg->header.arglen < sizeof(*ascii) + 1) ||
2762 (ascii->header.arglen < 1) ||
2763 (msg->header.arglen < sizeof(*ascii) +
2764 ascii->header.arglen)) {
2765 TRAP_ERROR();
2766 error = EINVAL;
2767 break;
2768 }
2769 ascii->data[ascii->header.arglen - 1] = '\0';
2770
2771 /* Get a response message with lots of room */
2772 NG_MKRESPONSE(resp, msg, sizeof(*binary) + bufSize, M_NOWAIT);
2773 if (resp == NULL) {
2774 error = ENOMEM;
2775 break;
2776 }
2777 binary = (struct ng_mesg *)resp->data;
2778
2779 /* Copy ASCII message header to response message payload */
2780 bcopy(ascii, binary, sizeof(*ascii));
2781
2782 /* Find command by matching ASCII command string */
2783 for (c = here->nd_type->cmdlist;
2784 c != NULL && c->name != NULL; c++) {
2785 if (strcmp(ascii->header.cmdstr, c->name) == 0)
2786 break;
2787 }
2788 if (c == NULL || c->name == NULL) {
2789 for (c = ng_generic_cmds; c->name != NULL; c++) {
2790 if (strcmp(ascii->header.cmdstr, c->name) == 0)
2791 break;
2792 }
2793 if (c->name == NULL) {
2794 NG_FREE_MSG(resp);
2795 error = ENOSYS;
2796 break;
2797 }
2798 }
2799
2800 /* Convert command name to binary */
2801 binary->header.cmd = c->cmd;
2802 binary->header.typecookie = c->cookie;
2803
2804 /* Convert command arguments to binary */
2805 argstype = (binary->header.flags & NGF_RESP) ?
2806 c->respType : c->mesgType;
2807 if (argstype == NULL) {
2808 bufSize = 0;
2809 } else {
2810 if ((error = ng_parse(argstype, ascii->data,
2811 &off, (u_char *)binary->data, &bufSize)) != 0) {
2812 NG_FREE_MSG(resp);
2813 break;
2814 }
2815 }
2816
2817 /* Return the result */
2818 binary->header.arglen = bufSize;
2819 resp->header.arglen = sizeof(*binary) + bufSize;
2820 break;
2821 }
2822
2823 case NGM_TEXT_CONFIG:
2824 case NGM_TEXT_STATUS:
2825 /*
2826 * This one is tricky as it passes the command down to the
2827 * actual node, even though it is a generic type command.
2828 * This means we must assume that the item/msg is already freed
2829 * when control passes back to us.
2830 */
2831 if (here->nd_type->rcvmsg != NULL) {
2832 NGI_MSG(item) = msg; /* put it back as we found it */
2833 return((*here->nd_type->rcvmsg)(here, item, lasthook));
2834 }
2835 /* Fall through if rcvmsg not supported */
2836 default:
2837 TRAP_ERROR();
2838 error = EINVAL;
2839 }
2840 /*
2841 * Sometimes a generic message may be statically allocated
2842 * to avoid problems with allocating when in tight memeory situations.
2843 * Don't free it if it is so.
2844 * I break them appart here, because erros may cause a free if the item
2845 * in which case we'd be doing it twice.
2846 * they are kept together above, to simplify freeing.
2847 */
2848 out:
2849 NG_RESPOND_MSG(error, here, item, resp);
2850 if (msg)
2851 NG_FREE_MSG(msg);
2852 return (error);
2853 }
2854
2855 /************************************************************************
2856 Queue element get/free routines
2857 ************************************************************************/
2858
2859 uma_zone_t ng_qzone;
2860 uma_zone_t ng_qdzone;
2861 static int maxalloc = 4096;/* limit the damage of a leak */
2862 static int maxdata = 512; /* limit the damage of a DoS */
2863
2864 TUNABLE_INT("net.graph.maxalloc", &maxalloc);
2865 SYSCTL_INT(_net_graph, OID_AUTO, maxalloc, CTLFLAG_RDTUN, &maxalloc,
2866 0, "Maximum number of non-data queue items to allocate");
2867 TUNABLE_INT("net.graph.maxdata", &maxdata);
2868 SYSCTL_INT(_net_graph, OID_AUTO, maxdata, CTLFLAG_RDTUN, &maxdata,
2869 0, "Maximum number of data queue items to allocate");
2870
2871 #ifdef NETGRAPH_DEBUG
2872 static TAILQ_HEAD(, ng_item) ng_itemlist = TAILQ_HEAD_INITIALIZER(ng_itemlist);
2873 static int allocated; /* number of items malloc'd */
2874 #endif
2875
2876 /*
2877 * Get a queue entry.
2878 * This is usually called when a packet first enters netgraph.
2879 * By definition, this is usually from an interrupt, or from a user.
2880 * Users are not so important, but try be quick for the times that it's
2881 * an interrupt.
2882 */
2883 static __inline item_p
2884 ng_alloc_item(int type, int flags)
2885 {
2886 item_p item;
2887
2888 KASSERT(((type & ~NGQF_TYPE) == 0),
2889 ("%s: incorrect item type: %d", __func__, type));
2890
2891 item = uma_zalloc((type == NGQF_DATA)?ng_qdzone:ng_qzone,
2892 ((flags & NG_WAITOK) ? M_WAITOK : M_NOWAIT) | M_ZERO);
2893
2894 if (item) {
2895 item->el_flags = type;
2896 #ifdef NETGRAPH_DEBUG
2897 mtx_lock(&ngq_mtx);
2898 TAILQ_INSERT_TAIL(&ng_itemlist, item, all);
2899 allocated++;
2900 mtx_unlock(&ngq_mtx);
2901 #endif
2902 }
2903
2904 return (item);
2905 }
2906
2907 /*
2908 * Release a queue entry
2909 */
2910 void
2911 ng_free_item(item_p item)
2912 {
2913 /*
2914 * The item may hold resources on it's own. We need to free
2915 * these before we can free the item. What they are depends upon
2916 * what kind of item it is. it is important that nodes zero
2917 * out pointers to resources that they remove from the item
2918 * or we release them again here.
2919 */
2920 switch (item->el_flags & NGQF_TYPE) {
2921 case NGQF_DATA:
2922 /* If we have an mbuf still attached.. */
2923 NG_FREE_M(_NGI_M(item));
2924 break;
2925 case NGQF_MESG:
2926 _NGI_RETADDR(item) = 0;
2927 NG_FREE_MSG(_NGI_MSG(item));
2928 break;
2929 case NGQF_FN:
2930 case NGQF_FN2:
2931 /* nothing to free really, */
2932 _NGI_FN(item) = NULL;
2933 _NGI_ARG1(item) = NULL;
2934 _NGI_ARG2(item) = 0;
2935 break;
2936 }
2937 /* If we still have a node or hook referenced... */
2938 _NGI_CLR_NODE(item);
2939 _NGI_CLR_HOOK(item);
2940
2941 #ifdef NETGRAPH_DEBUG
2942 mtx_lock(&ngq_mtx);
2943 TAILQ_REMOVE(&ng_itemlist, item, all);
2944 allocated--;
2945 mtx_unlock(&ngq_mtx);
2946 #endif
2947 uma_zfree(((item->el_flags & NGQF_TYPE) == NGQF_DATA)?
2948 ng_qdzone:ng_qzone, item);
2949 }
2950
2951 /*
2952 * Change type of the queue entry.
2953 * Possibly reallocates it from another UMA zone.
2954 */
2955 static __inline item_p
2956 ng_realloc_item(item_p pitem, int type, int flags)
2957 {
2958 item_p item;
2959 int from, to;
2960
2961 KASSERT((pitem != NULL), ("%s: can't reallocate NULL", __func__));
2962 KASSERT(((type & ~NGQF_TYPE) == 0),
2963 ("%s: incorrect item type: %d", __func__, type));
2964
2965 from = ((pitem->el_flags & NGQF_TYPE) == NGQF_DATA);
2966 to = (type == NGQF_DATA);
2967 if (from != to) {
2968 /* If reallocation is required do it and copy item. */
2969 if ((item = ng_alloc_item(type, flags)) == NULL) {
2970 ng_free_item(pitem);
2971 return (NULL);
2972 }
2973 *item = *pitem;
2974 ng_free_item(pitem);
2975 } else
2976 item = pitem;
2977 item->el_flags = (item->el_flags & ~NGQF_TYPE) | type;
2978
2979 return (item);
2980 }
2981
2982 /************************************************************************
2983 Module routines
2984 ************************************************************************/
2985
2986 /*
2987 * Handle the loading/unloading of a netgraph node type module
2988 */
2989 int
2990 ng_mod_event(module_t mod, int event, void *data)
2991 {
2992 struct ng_type *const type = data;
2993 int s, error = 0;
2994
2995 switch (event) {
2996 case MOD_LOAD:
2997
2998 /* Register new netgraph node type */
2999 s = splnet();
3000 if ((error = ng_newtype(type)) != 0) {
3001 splx(s);
3002 break;
3003 }
3004
3005 /* Call type specific code */
3006 if (type->mod_event != NULL)
3007 if ((error = (*type->mod_event)(mod, event, data))) {
3008 mtx_lock(&ng_typelist_mtx);
3009 type->refs--; /* undo it */
3010 LIST_REMOVE(type, types);
3011 mtx_unlock(&ng_typelist_mtx);
3012 }
3013 splx(s);
3014 break;
3015
3016 case MOD_UNLOAD:
3017 s = splnet();
3018 if (type->refs > 1) { /* make sure no nodes exist! */
3019 error = EBUSY;
3020 } else {
3021 if (type->refs == 0) {
3022 /* failed load, nothing to undo */
3023 splx(s);
3024 break;
3025 }
3026 if (type->mod_event != NULL) { /* check with type */
3027 error = (*type->mod_event)(mod, event, data);
3028 if (error != 0) { /* type refuses.. */
3029 splx(s);
3030 break;
3031 }
3032 }
3033 mtx_lock(&ng_typelist_mtx);
3034 LIST_REMOVE(type, types);
3035 mtx_unlock(&ng_typelist_mtx);
3036 }
3037 splx(s);
3038 break;
3039
3040 default:
3041 if (type->mod_event != NULL)
3042 error = (*type->mod_event)(mod, event, data);
3043 else
3044 error = EOPNOTSUPP; /* XXX ? */
3045 break;
3046 }
3047 return (error);
3048 }
3049
3050 /*
3051 * Handle loading and unloading for this code.
3052 * The only thing we need to link into is the NETISR strucure.
3053 */
3054 static int
3055 ngb_mod_event(module_t mod, int event, void *data)
3056 {
3057 int error = 0;
3058
3059 switch (event) {
3060 case MOD_LOAD:
3061 /* Initialize everything. */
3062 NG_WORKLIST_LOCK_INIT();
3063 mtx_init(&ng_typelist_mtx, "netgraph types mutex", NULL,
3064 MTX_DEF);
3065 mtx_init(&ng_idhash_mtx, "netgraph idhash mutex", NULL,
3066 MTX_DEF);
3067 mtx_init(&ng_namehash_mtx, "netgraph namehash mutex", NULL,
3068 MTX_DEF);
3069 mtx_init(&ng_topo_mtx, "netgraph topology mutex", NULL,
3070 MTX_DEF);
3071 #ifdef NETGRAPH_DEBUG
3072 mtx_init(&ng_nodelist_mtx, "netgraph nodelist mutex", NULL,
3073 MTX_DEF);
3074 mtx_init(&ngq_mtx, "netgraph item list mutex", NULL,
3075 MTX_DEF);
3076 #endif
3077 ng_qzone = uma_zcreate("NetGraph items", sizeof(struct ng_item),
3078 NULL, NULL, NULL, NULL, UMA_ALIGN_CACHE, 0);
3079 uma_zone_set_max(ng_qzone, maxalloc);
3080 ng_qdzone = uma_zcreate("NetGraph data items", sizeof(struct ng_item),
3081 NULL, NULL, NULL, NULL, UMA_ALIGN_CACHE, 0);
3082 uma_zone_set_max(ng_qdzone, maxdata);
3083 netisr_register(NETISR_NETGRAPH, (netisr_t *)ngintr, NULL,
3084 NETISR_MPSAFE);
3085 break;
3086 case MOD_UNLOAD:
3087 /* You can't unload it because an interface may be using it. */
3088 error = EBUSY;
3089 break;
3090 default:
3091 error = EOPNOTSUPP;
3092 break;
3093 }
3094 return (error);
3095 }
3096
3097 static moduledata_t netgraph_mod = {
3098 "netgraph",
3099 ngb_mod_event,
3100 (NULL)
3101 };
3102 DECLARE_MODULE(netgraph, netgraph_mod, SI_SUB_NETGRAPH, SI_ORDER_MIDDLE);
3103 SYSCTL_NODE(_net, OID_AUTO, graph, CTLFLAG_RW, 0, "netgraph Family");
3104 SYSCTL_INT(_net_graph, OID_AUTO, abi_version, CTLFLAG_RD, 0, NG_ABI_VERSION,"");
3105 SYSCTL_INT(_net_graph, OID_AUTO, msg_version, CTLFLAG_RD, 0, NG_VERSION, "");
3106
3107 #ifdef NETGRAPH_DEBUG
3108 void
3109 dumphook (hook_p hook, char *file, int line)
3110 {
3111 printf("hook: name %s, %d refs, Last touched:\n",
3112 _NG_HOOK_NAME(hook), hook->hk_refs);
3113 printf(" Last active @ %s, line %d\n",
3114 hook->lastfile, hook->lastline);
3115 if (line) {
3116 printf(" problem discovered at file %s, line %d\n", file, line);
3117 }
3118 }
3119
3120 void
3121 dumpnode(node_p node, char *file, int line)
3122 {
3123 printf("node: ID [%x]: type '%s', %d hooks, flags 0x%x, %d refs, %s:\n",
3124 _NG_NODE_ID(node), node->nd_type->name,
3125 node->nd_numhooks, node->nd_flags,
3126 node->nd_refs, node->nd_name);
3127 printf(" Last active @ %s, line %d\n",
3128 node->lastfile, node->lastline);
3129 if (line) {
3130 printf(" problem discovered at file %s, line %d\n", file, line);
3131 }
3132 }
3133
3134 void
3135 dumpitem(item_p item, char *file, int line)
3136 {
3137 printf(" ACTIVE item, last used at %s, line %d",
3138 item->lastfile, item->lastline);
3139 switch(item->el_flags & NGQF_TYPE) {
3140 case NGQF_DATA:
3141 printf(" - [data]\n");
3142 break;
3143 case NGQF_MESG:
3144 printf(" - retaddr[%d]:\n", _NGI_RETADDR(item));
3145 break;
3146 case NGQF_FN:
3147 printf(" - fn@%p (%p, %p, %p, %d (%x))\n",
3148 _NGI_FN(item),
3149 _NGI_NODE(item),
3150 _NGI_HOOK(item),
3151 item->body.fn.fn_arg1,
3152 item->body.fn.fn_arg2,
3153 item->body.fn.fn_arg2);
3154 break;
3155 case NGQF_FN2:
3156 printf(" - fn2@%p (%p, %p, %p, %d (%x))\n",
3157 _NGI_FN2(item),
3158 _NGI_NODE(item),
3159 _NGI_HOOK(item),
3160 item->body.fn.fn_arg1,
3161 item->body.fn.fn_arg2,
3162 item->body.fn.fn_arg2);
3163 break;
3164 }
3165 if (line) {
3166 printf(" problem discovered at file %s, line %d\n", file, line);
3167 if (_NGI_NODE(item)) {
3168 printf("node %p ([%x])\n",
3169 _NGI_NODE(item), ng_node2ID(_NGI_NODE(item)));
3170 }
3171 }
3172 }
3173
3174 static void
3175 ng_dumpitems(void)
3176 {
3177 item_p item;
3178 int i = 1;
3179 TAILQ_FOREACH(item, &ng_itemlist, all) {
3180 printf("[%d] ", i++);
3181 dumpitem(item, NULL, 0);
3182 }
3183 }
3184
3185 static void
3186 ng_dumpnodes(void)
3187 {
3188 node_p node;
3189 int i = 1;
3190 mtx_lock(&ng_nodelist_mtx);
3191 SLIST_FOREACH(node, &ng_allnodes, nd_all) {
3192 printf("[%d] ", i++);
3193 dumpnode(node, NULL, 0);
3194 }
3195 mtx_unlock(&ng_nodelist_mtx);
3196 }
3197
3198 static void
3199 ng_dumphooks(void)
3200 {
3201 hook_p hook;
3202 int i = 1;
3203 mtx_lock(&ng_nodelist_mtx);
3204 SLIST_FOREACH(hook, &ng_allhooks, hk_all) {
3205 printf("[%d] ", i++);
3206 dumphook(hook, NULL, 0);
3207 }
3208 mtx_unlock(&ng_nodelist_mtx);
3209 }
3210
3211 static int
3212 sysctl_debug_ng_dump_items(SYSCTL_HANDLER_ARGS)
3213 {
3214 int error;
3215 int val;
3216 int i;
3217
3218 val = allocated;
3219 i = 1;
3220 error = sysctl_handle_int(oidp, &val, 0, req);
3221 if (error != 0 || req->newptr == NULL)
3222 return (error);
3223 if (val == 42) {
3224 ng_dumpitems();
3225 ng_dumpnodes();
3226 ng_dumphooks();
3227 }
3228 return (0);
3229 }
3230
3231 SYSCTL_PROC(_debug, OID_AUTO, ng_dump_items, CTLTYPE_INT | CTLFLAG_RW,
3232 0, sizeof(int), sysctl_debug_ng_dump_items, "I", "Number of allocated items");
3233 #endif /* NETGRAPH_DEBUG */
3234
3235
3236 /***********************************************************************
3237 * Worklist routines
3238 **********************************************************************/
3239 /* NETISR thread enters here */
3240 /*
3241 * Pick a node off the list of nodes with work,
3242 * try get an item to process off it.
3243 * If there are no more, remove the node from the list.
3244 */
3245 static void
3246 ngintr(void)
3247 {
3248 for (;;) {
3249 node_p node;
3250
3251 /* Get node from the worklist. */
3252 NG_WORKLIST_LOCK();
3253 node = TAILQ_FIRST(&ng_worklist);
3254 if (!node) {
3255 NG_WORKLIST_UNLOCK();
3256 break;
3257 }
3258 TAILQ_REMOVE(&ng_worklist, node, nd_work);
3259 NG_WORKLIST_UNLOCK();
3260 CTR3(KTR_NET, "%20s: node [%x] (%p) taken off worklist",
3261 __func__, node->nd_ID, node);
3262 /*
3263 * We have the node. We also take over the reference
3264 * that the list had on it.
3265 * Now process as much as you can, until it won't
3266 * let you have another item off the queue.
3267 * All this time, keep the reference
3268 * that lets us be sure that the node still exists.
3269 * Let the reference go at the last minute.
3270 */
3271 for (;;) {
3272 item_p item;
3273 int rw;
3274
3275 NG_QUEUE_LOCK(&node->nd_input_queue);
3276 item = ng_dequeue(&node->nd_input_queue, &rw);
3277 if (item == NULL) {
3278 atomic_clear_int(&node->nd_flags, NGF_WORKQ);
3279 NG_QUEUE_UNLOCK(&node->nd_input_queue);
3280 break; /* go look for another node */
3281 } else {
3282 NG_QUEUE_UNLOCK(&node->nd_input_queue);
3283 NGI_GET_NODE(item, node); /* zaps stored node */
3284 ng_apply_item(node, item, rw);
3285 NG_NODE_UNREF(node);
3286 }
3287 }
3288 NG_NODE_UNREF(node);
3289 }
3290 }
3291
3292 /*
3293 * XXX
3294 * It's posible that a debugging NG_NODE_REF may need
3295 * to be outside the mutex zone
3296 */
3297 static void
3298 ng_worklist_add(node_p node)
3299 {
3300
3301 mtx_assert(&node->nd_input_queue.q_mtx, MA_OWNED);
3302
3303 if ((node->nd_flags & NGF_WORKQ) == 0) {
3304 /*
3305 * If we are not already on the work queue,
3306 * then put us on.
3307 */
3308 atomic_set_int(&node->nd_flags, NGF_WORKQ);
3309 NG_NODE_REF(node); /* XXX fafe in mutex? */
3310 NG_WORKLIST_LOCK();
3311 TAILQ_INSERT_TAIL(&ng_worklist, node, nd_work);
3312 NG_WORKLIST_UNLOCK();
3313 schednetisr(NETISR_NETGRAPH);
3314 CTR3(KTR_NET, "%20s: node [%x] (%p) put on worklist", __func__,
3315 node->nd_ID, node);
3316 } else {
3317 CTR3(KTR_NET, "%20s: node [%x] (%p) already on worklist",
3318 __func__, node->nd_ID, node);
3319 }
3320 }
3321
3322
3323 /***********************************************************************
3324 * Externally useable functions to set up a queue item ready for sending
3325 ***********************************************************************/
3326
3327 #ifdef NETGRAPH_DEBUG
3328 #define ITEM_DEBUG_CHECKS \
3329 do { \
3330 if (NGI_NODE(item) ) { \
3331 printf("item already has node"); \
3332 kdb_enter_why(KDB_WHY_NETGRAPH, "has node"); \
3333 NGI_CLR_NODE(item); \
3334 } \
3335 if (NGI_HOOK(item) ) { \
3336 printf("item already has hook"); \
3337 kdb_enter_why(KDB_WHY_NETGRAPH, "has hook"); \
3338 NGI_CLR_HOOK(item); \
3339 } \
3340 } while (0)
3341 #else
3342 #define ITEM_DEBUG_CHECKS
3343 #endif
3344
3345 /*
3346 * Put mbuf into the item.
3347 * Hook and node references will be removed when the item is dequeued.
3348 * (or equivalent)
3349 * (XXX) Unsafe because no reference held by peer on remote node.
3350 * remote node might go away in this timescale.
3351 * We know the hooks can't go away because that would require getting
3352 * a writer item on both nodes and we must have at least a reader
3353 * here to be able to do this.
3354 * Note that the hook loaded is the REMOTE hook.
3355 *
3356 * This is possibly in the critical path for new data.
3357 */
3358 item_p
3359 ng_package_data(struct mbuf *m, int flags)
3360 {
3361 item_p item;
3362
3363 if ((item = ng_alloc_item(NGQF_DATA, flags)) == NULL) {
3364 NG_FREE_M(m);
3365 return (NULL);
3366 }
3367 ITEM_DEBUG_CHECKS;
3368 item->el_flags |= NGQF_READER;
3369 NGI_M(item) = m;
3370 return (item);
3371 }
3372
3373 /*
3374 * Allocate a queue item and put items into it..
3375 * Evaluate the address as this will be needed to queue it and
3376 * to work out what some of the fields should be.
3377 * Hook and node references will be removed when the item is dequeued.
3378 * (or equivalent)
3379 */
3380 item_p
3381 ng_package_msg(struct ng_mesg *msg, int flags)
3382 {
3383 item_p item;
3384
3385 if ((item = ng_alloc_item(NGQF_MESG, flags)) == NULL) {
3386 NG_FREE_MSG(msg);
3387 return (NULL);
3388 }
3389 ITEM_DEBUG_CHECKS;
3390 /* Messages items count as writers unless explicitly exempted. */
3391 if (msg->header.cmd & NGM_READONLY)
3392 item->el_flags |= NGQF_READER;
3393 else
3394 item->el_flags |= NGQF_WRITER;
3395 /*
3396 * Set the current lasthook into the queue item
3397 */
3398 NGI_MSG(item) = msg;
3399 NGI_RETADDR(item) = 0;
3400 return (item);
3401 }
3402
3403
3404
3405 #define SET_RETADDR(item, here, retaddr) \
3406 do { /* Data or fn items don't have retaddrs */ \
3407 if ((item->el_flags & NGQF_TYPE) == NGQF_MESG) { \
3408 if (retaddr) { \
3409 NGI_RETADDR(item) = retaddr; \
3410 } else { \
3411 /* \
3412 * The old return address should be ok. \
3413 * If there isn't one, use the address \
3414 * here. \
3415 */ \
3416 if (NGI_RETADDR(item) == 0) { \
3417 NGI_RETADDR(item) \
3418 = ng_node2ID(here); \
3419 } \
3420 } \
3421 } \
3422 } while (0)
3423
3424 int
3425 ng_address_hook(node_p here, item_p item, hook_p hook, ng_ID_t retaddr)
3426 {
3427 hook_p peer;
3428 node_p peernode;
3429 ITEM_DEBUG_CHECKS;
3430 /*
3431 * Quick sanity check..
3432 * Since a hook holds a reference on it's node, once we know
3433 * that the peer is still connected (even if invalid,) we know
3434 * that the peer node is present, though maybe invalid.
3435 */
3436 if ((hook == NULL) ||
3437 NG_HOOK_NOT_VALID(hook) ||
3438 NG_HOOK_NOT_VALID(peer = NG_HOOK_PEER(hook)) ||
3439 NG_NODE_NOT_VALID(peernode = NG_PEER_NODE(hook))) {
3440 NG_FREE_ITEM(item);
3441 TRAP_ERROR();
3442 return (ENETDOWN);
3443 }
3444
3445 /*
3446 * Transfer our interest to the other (peer) end.
3447 */
3448 NG_HOOK_REF(peer);
3449 NG_NODE_REF(peernode);
3450 NGI_SET_HOOK(item, peer);
3451 NGI_SET_NODE(item, peernode);
3452 SET_RETADDR(item, here, retaddr);
3453 return (0);
3454 }
3455
3456 int
3457 ng_address_path(node_p here, item_p item, char *address, ng_ID_t retaddr)
3458 {
3459 node_p dest = NULL;
3460 hook_p hook = NULL;
3461 int error;
3462
3463 ITEM_DEBUG_CHECKS;
3464 /*
3465 * Note that ng_path2noderef increments the reference count
3466 * on the node for us if it finds one. So we don't have to.
3467 */
3468 error = ng_path2noderef(here, address, &dest, &hook);
3469 if (error) {
3470 NG_FREE_ITEM(item);
3471 return (error);
3472 }
3473 NGI_SET_NODE(item, dest);
3474 if ( hook) {
3475 NG_HOOK_REF(hook); /* don't let it go while on the queue */
3476 NGI_SET_HOOK(item, hook);
3477 }
3478 SET_RETADDR(item, here, retaddr);
3479 return (0);
3480 }
3481
3482 int
3483 ng_address_ID(node_p here, item_p item, ng_ID_t ID, ng_ID_t retaddr)
3484 {
3485 node_p dest;
3486
3487 ITEM_DEBUG_CHECKS;
3488 /*
3489 * Find the target node.
3490 */
3491 dest = ng_ID2noderef(ID); /* GETS REFERENCE! */
3492 if (dest == NULL) {
3493 NG_FREE_ITEM(item);
3494 TRAP_ERROR();
3495 return(EINVAL);
3496 }
3497 /* Fill out the contents */
3498 NGI_SET_NODE(item, dest);
3499 NGI_CLR_HOOK(item);
3500 SET_RETADDR(item, here, retaddr);
3501 return (0);
3502 }
3503
3504 /*
3505 * special case to send a message to self (e.g. destroy node)
3506 * Possibly indicate an arrival hook too.
3507 * Useful for removing that hook :-)
3508 */
3509 item_p
3510 ng_package_msg_self(node_p here, hook_p hook, struct ng_mesg *msg)
3511 {
3512 item_p item;
3513
3514 /*
3515 * Find the target node.
3516 * If there is a HOOK argument, then use that in preference
3517 * to the address.
3518 */
3519 if ((item = ng_alloc_item(NGQF_MESG, NG_NOFLAGS)) == NULL) {
3520 NG_FREE_MSG(msg);
3521 return (NULL);
3522 }
3523
3524 /* Fill out the contents */
3525 item->el_flags |= NGQF_WRITER;
3526 NG_NODE_REF(here);
3527 NGI_SET_NODE(item, here);
3528 if (hook) {
3529 NG_HOOK_REF(hook);
3530 NGI_SET_HOOK(item, hook);
3531 }
3532 NGI_MSG(item) = msg;
3533 NGI_RETADDR(item) = ng_node2ID(here);
3534 return (item);
3535 }
3536
3537 /*
3538 * Send ng_item_fn function call to the specified node.
3539 */
3540
3541 int
3542 ng_send_fn(node_p node, hook_p hook, ng_item_fn *fn, void * arg1, int arg2)
3543 {
3544
3545 return ng_send_fn1(node, hook, fn, arg1, arg2, NG_NOFLAGS);
3546 }
3547
3548 int
3549 ng_send_fn1(node_p node, hook_p hook, ng_item_fn *fn, void * arg1, int arg2,
3550 int flags)
3551 {
3552 item_p item;
3553
3554 if ((item = ng_alloc_item(NGQF_FN, flags)) == NULL) {
3555 return (ENOMEM);
3556 }
3557 item->el_flags |= NGQF_WRITER;
3558 NG_NODE_REF(node); /* and one for the item */
3559 NGI_SET_NODE(item, node);
3560 if (hook) {
3561 NG_HOOK_REF(hook);
3562 NGI_SET_HOOK(item, hook);
3563 }
3564 NGI_FN(item) = fn;
3565 NGI_ARG1(item) = arg1;
3566 NGI_ARG2(item) = arg2;
3567 return(ng_snd_item(item, flags));
3568 }
3569
3570 /*
3571 * Send ng_item_fn2 function call to the specified node.
3572 *
3573 * If an optional pitem parameter is supplied, its apply
3574 * callback will be copied to the new item. If also NG_REUSE_ITEM
3575 * flag is set, no new item will be allocated, but pitem will
3576 * be used.
3577 */
3578 int
3579 ng_send_fn2(node_p node, hook_p hook, item_p pitem, ng_item_fn2 *fn, void *arg1,
3580 int arg2, int flags)
3581 {
3582 item_p item;
3583
3584 KASSERT((pitem != NULL || (flags & NG_REUSE_ITEM) == 0),
3585 ("%s: NG_REUSE_ITEM but no pitem", __func__));
3586
3587 /*
3588 * Allocate a new item if no supplied or
3589 * if we can't use supplied one.
3590 */
3591 if (pitem == NULL || (flags & NG_REUSE_ITEM) == 0) {
3592 if ((item = ng_alloc_item(NGQF_FN2, flags)) == NULL)
3593 return (ENOMEM);
3594 if (pitem != NULL)
3595 item->apply = pitem->apply;
3596 } else {
3597 if ((item = ng_realloc_item(pitem, NGQF_FN2, flags)) == NULL)
3598 return (ENOMEM);
3599 }
3600
3601 item->el_flags = (item->el_flags & ~NGQF_RW) | NGQF_WRITER;
3602 NG_NODE_REF(node); /* and one for the item */
3603 NGI_SET_NODE(item, node);
3604 if (hook) {
3605 NG_HOOK_REF(hook);
3606 NGI_SET_HOOK(item, hook);
3607 }
3608 NGI_FN2(item) = fn;
3609 NGI_ARG1(item) = arg1;
3610 NGI_ARG2(item) = arg2;
3611 return(ng_snd_item(item, flags));
3612 }
3613
3614 /*
3615 * Official timeout routines for Netgraph nodes.
3616 */
3617 static void
3618 ng_callout_trampoline(void *arg)
3619 {
3620 item_p item = arg;
3621
3622 ng_snd_item(item, 0);
3623 }
3624
3625
3626 int
3627 ng_callout(struct callout *c, node_p node, hook_p hook, int ticks,
3628 ng_item_fn *fn, void * arg1, int arg2)
3629 {
3630 item_p item, oitem;
3631
3632 if ((item = ng_alloc_item(NGQF_FN, NG_NOFLAGS)) == NULL)
3633 return (ENOMEM);
3634
3635 item->el_flags |= NGQF_WRITER;
3636 NG_NODE_REF(node); /* and one for the item */
3637 NGI_SET_NODE(item, node);
3638 if (hook) {
3639 NG_HOOK_REF(hook);
3640 NGI_SET_HOOK(item, hook);
3641 }
3642 NGI_FN(item) = fn;
3643 NGI_ARG1(item) = arg1;
3644 NGI_ARG2(item) = arg2;
3645 oitem = c->c_arg;
3646 if (callout_reset(c, ticks, &ng_callout_trampoline, item) == 1 &&
3647 oitem != NULL)
3648 NG_FREE_ITEM(oitem);
3649 return (0);
3650 }
3651
3652 /* A special modified version of untimeout() */
3653 int
3654 ng_uncallout(struct callout *c, node_p node)
3655 {
3656 item_p item;
3657 int rval;
3658
3659 KASSERT(c != NULL, ("ng_uncallout: NULL callout"));
3660 KASSERT(node != NULL, ("ng_uncallout: NULL node"));
3661
3662 rval = callout_stop(c);
3663 item = c->c_arg;
3664 /* Do an extra check */
3665 if ((rval > 0) && (c->c_func == &ng_callout_trampoline) &&
3666 (NGI_NODE(item) == node)) {
3667 /*
3668 * We successfully removed it from the queue before it ran
3669 * So now we need to unreference everything that was
3670 * given extra references. (NG_FREE_ITEM does this).
3671 */
3672 NG_FREE_ITEM(item);
3673 }
3674 c->c_arg = NULL;
3675
3676 return (rval);
3677 }
3678
3679 /*
3680 * Set the address, if none given, give the node here.
3681 */
3682 void
3683 ng_replace_retaddr(node_p here, item_p item, ng_ID_t retaddr)
3684 {
3685 if (retaddr) {
3686 NGI_RETADDR(item) = retaddr;
3687 } else {
3688 /*
3689 * The old return address should be ok.
3690 * If there isn't one, use the address here.
3691 */
3692 NGI_RETADDR(item) = ng_node2ID(here);
3693 }
3694 }
3695
3696 #define TESTING
3697 #ifdef TESTING
3698 /* just test all the macros */
3699 void
3700 ng_macro_test(item_p item);
3701 void
3702 ng_macro_test(item_p item)
3703 {
3704 node_p node = NULL;
3705 hook_p hook = NULL;
3706 struct mbuf *m;
3707 struct ng_mesg *msg;
3708 ng_ID_t retaddr;
3709 int error;
3710
3711 NGI_GET_M(item, m);
3712 NGI_GET_MSG(item, msg);
3713 retaddr = NGI_RETADDR(item);
3714 NG_SEND_DATA(error, hook, m, NULL);
3715 NG_SEND_DATA_ONLY(error, hook, m);
3716 NG_FWD_NEW_DATA(error, item, hook, m);
3717 NG_FWD_ITEM_HOOK(error, item, hook);
3718 NG_SEND_MSG_HOOK(error, node, msg, hook, retaddr);
3719 NG_SEND_MSG_ID(error, node, msg, retaddr, retaddr);
3720 NG_SEND_MSG_PATH(error, node, msg, ".:", retaddr);
3721 NG_FWD_MSG_HOOK(error, node, item, hook, retaddr);
3722 }
3723 #endif /* TESTING */
3724
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