1 /*
2 * ng_base.c
3 */
4
5 /*-
6 * Copyright (c) 1996-1999 Whistle Communications, Inc.
7 * All rights reserved.
8 *
9 * Subject to the following obligations and disclaimer of warranty, use and
10 * redistribution of this software, in source or object code forms, with or
11 * without modifications are expressly permitted by Whistle Communications;
12 * provided, however, that:
13 * 1. Any and all reproductions of the source or object code must include the
14 * copyright notice above and the following disclaimer of warranties; and
15 * 2. No rights are granted, in any manner or form, to use Whistle
16 * Communications, Inc. trademarks, including the mark "WHISTLE
17 * COMMUNICATIONS" on advertising, endorsements, or otherwise except as
18 * such appears in the above copyright notice or in the software.
19 *
20 * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
21 * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
22 * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
23 * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
24 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
25 * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
26 * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
27 * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
28 * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
29 * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
30 * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
31 * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
32 * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
33 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
34 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
35 * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
36 * OF SUCH DAMAGE.
37 *
38 * Authors: Julian Elischer <julian@freebsd.org>
39 * Archie Cobbs <archie@freebsd.org>
40 *
41 * $FreeBSD: releng/6.1/sys/netgraph/ng_base.c 154613 2006-01-21 09:59:43Z glebius $
42 * $Whistle: ng_base.c,v 1.39 1999/01/28 23:54:53 julian Exp $
43 */
44
45 /*
46 * This file implements the base netgraph code.
47 */
48
49 #include <sys/param.h>
50 #include <sys/systm.h>
51 #include <sys/ctype.h>
52 #include <sys/errno.h>
53 #include <sys/kdb.h>
54 #include <sys/kernel.h>
55 #include <sys/ktr.h>
56 #include <sys/limits.h>
57 #include <sys/malloc.h>
58 #include <sys/mbuf.h>
59 #include <sys/queue.h>
60 #include <sys/sysctl.h>
61 #include <sys/syslog.h>
62
63 #include <net/netisr.h>
64
65 #include <netgraph/ng_message.h>
66 #include <netgraph/netgraph.h>
67 #include <netgraph/ng_parse.h>
68
69 MODULE_VERSION(netgraph, NG_ABI_VERSION);
70
71 /* List of all active nodes */
72 static LIST_HEAD(, ng_node) ng_nodelist;
73 static struct mtx ng_nodelist_mtx;
74
75 /* Mutex to protect topology events. */
76 static struct mtx ng_topo_mtx;
77
78 #ifdef NETGRAPH_DEBUG
79 static struct mtx ngq_mtx; /* protects the queue item list */
80
81 static SLIST_HEAD(, ng_node) ng_allnodes;
82 static LIST_HEAD(, ng_node) ng_freenodes; /* in debug, we never free() them */
83 static SLIST_HEAD(, ng_hook) ng_allhooks;
84 static LIST_HEAD(, ng_hook) ng_freehooks; /* in debug, we never free() them */
85
86 static void ng_dumpitems(void);
87 static void ng_dumpnodes(void);
88 static void ng_dumphooks(void);
89
90 #endif /* NETGRAPH_DEBUG */
91 /*
92 * DEAD versions of the structures.
93 * In order to avoid races, it is sometimes neccesary to point
94 * at SOMETHING even though theoretically, the current entity is
95 * INVALID. Use these to avoid these races.
96 */
97 struct ng_type ng_deadtype = {
98 NG_ABI_VERSION,
99 "dead",
100 NULL, /* modevent */
101 NULL, /* constructor */
102 NULL, /* rcvmsg */
103 NULL, /* shutdown */
104 NULL, /* newhook */
105 NULL, /* findhook */
106 NULL, /* connect */
107 NULL, /* rcvdata */
108 NULL, /* disconnect */
109 NULL, /* cmdlist */
110 };
111
112 struct ng_node ng_deadnode = {
113 "dead",
114 &ng_deadtype,
115 NGF_INVALID,
116 1, /* refs */
117 0, /* numhooks */
118 NULL, /* private */
119 0, /* ID */
120 LIST_HEAD_INITIALIZER(ng_deadnode.hooks),
121 {}, /* all_nodes list entry */
122 {}, /* id hashtable list entry */
123 {}, /* workqueue entry */
124 { 0,
125 {}, /* should never use! (should hang) */
126 NULL,
127 &ng_deadnode.nd_input_queue.queue,
128 &ng_deadnode
129 },
130 #ifdef NETGRAPH_DEBUG
131 ND_MAGIC,
132 __FILE__,
133 __LINE__,
134 {NULL}
135 #endif /* NETGRAPH_DEBUG */
136 };
137
138 struct ng_hook ng_deadhook = {
139 "dead",
140 NULL, /* private */
141 HK_INVALID | HK_DEAD,
142 1, /* refs always >= 1 */
143 0, /* undefined data link type */
144 &ng_deadhook, /* Peer is self */
145 &ng_deadnode, /* attached to deadnode */
146 {}, /* hooks list */
147 NULL, /* override rcvmsg() */
148 NULL, /* override rcvdata() */
149 #ifdef NETGRAPH_DEBUG
150 HK_MAGIC,
151 __FILE__,
152 __LINE__,
153 {NULL}
154 #endif /* NETGRAPH_DEBUG */
155 };
156
157 /*
158 * END DEAD STRUCTURES
159 */
160 /* List nodes with unallocated work */
161 static TAILQ_HEAD(, ng_node) ng_worklist = TAILQ_HEAD_INITIALIZER(ng_worklist);
162 static struct mtx ng_worklist_mtx; /* MUST LOCK NODE FIRST */
163
164 /* List of installed types */
165 static LIST_HEAD(, ng_type) ng_typelist;
166 static struct mtx ng_typelist_mtx;
167
168 /* Hash related definitions */
169 /* XXX Don't need to initialise them because it's a LIST */
170 #define NG_ID_HASH_SIZE 32 /* most systems wont need even this many */
171 static LIST_HEAD(, ng_node) ng_ID_hash[NG_ID_HASH_SIZE];
172 static struct mtx ng_idhash_mtx;
173 /* Method to find a node.. used twice so do it here */
174 #define NG_IDHASH_FN(ID) ((ID) % (NG_ID_HASH_SIZE))
175 #define NG_IDHASH_FIND(ID, node) \
176 do { \
177 mtx_assert(&ng_idhash_mtx, MA_OWNED); \
178 LIST_FOREACH(node, &ng_ID_hash[NG_IDHASH_FN(ID)], \
179 nd_idnodes) { \
180 if (NG_NODE_IS_VALID(node) \
181 && (NG_NODE_ID(node) == ID)) { \
182 break; \
183 } \
184 } \
185 } while (0)
186
187
188 /* Internal functions */
189 static int ng_add_hook(node_p node, const char *name, hook_p * hookp);
190 static int ng_generic_msg(node_p here, item_p item, hook_p lasthook);
191 static ng_ID_t ng_decodeidname(const char *name);
192 static int ngb_mod_event(module_t mod, int event, void *data);
193 static void ng_worklist_remove(node_p node);
194 static void ngintr(void);
195 static int ng_apply_item(node_p node, item_p item, int rw);
196 static void ng_flush_input_queue(struct ng_queue * ngq);
197 static void ng_setisr(node_p node);
198 static node_p ng_ID2noderef(ng_ID_t ID);
199 static int ng_con_nodes(node_p node, const char *name, node_p node2,
200 const char *name2);
201 static void ng_con_part2(node_p node, hook_p hook, void *arg1, int arg2);
202 static void ng_con_part3(node_p node, hook_p hook, void *arg1, int arg2);
203 static int ng_mkpeer(node_p node, const char *name,
204 const char *name2, char *type);
205
206 /* Imported, these used to be externally visible, some may go back. */
207 void ng_destroy_hook(hook_p hook);
208 node_p ng_name2noderef(node_p node, const char *name);
209 int ng_path2noderef(node_p here, const char *path,
210 node_p *dest, hook_p *lasthook);
211 int ng_make_node(const char *type, node_p *nodepp);
212 int ng_path_parse(char *addr, char **node, char **path, char **hook);
213 void ng_rmnode(node_p node, hook_p dummy1, void *dummy2, int dummy3);
214 void ng_unname(node_p node);
215
216
217 /* Our own netgraph malloc type */
218 MALLOC_DEFINE(M_NETGRAPH, "netgraph", "netgraph structures and ctrl messages");
219 MALLOC_DEFINE(M_NETGRAPH_HOOK, "netgraph_hook", "netgraph hook structures");
220 MALLOC_DEFINE(M_NETGRAPH_NODE, "netgraph_node", "netgraph node structures");
221 MALLOC_DEFINE(M_NETGRAPH_ITEM, "netgraph_item", "netgraph item structures");
222 MALLOC_DEFINE(M_NETGRAPH_MSG, "netgraph_msg", "netgraph name storage");
223
224 /* Should not be visible outside this file */
225
226 #define _NG_ALLOC_HOOK(hook) \
227 MALLOC(hook, hook_p, sizeof(*hook), M_NETGRAPH_HOOK, M_NOWAIT | M_ZERO)
228 #define _NG_ALLOC_NODE(node) \
229 MALLOC(node, node_p, sizeof(*node), M_NETGRAPH_NODE, M_NOWAIT | M_ZERO)
230
231 #ifdef NETGRAPH_DEBUG /*----------------------------------------------*/
232 /*
233 * In debug mode:
234 * In an attempt to help track reference count screwups
235 * we do not free objects back to the malloc system, but keep them
236 * in a local cache where we can examine them and keep information safely
237 * after they have been freed.
238 * We use this scheme for nodes and hooks, and to some extent for items.
239 */
240 static __inline hook_p
241 ng_alloc_hook(void)
242 {
243 hook_p hook;
244 SLIST_ENTRY(ng_hook) temp;
245 mtx_lock(&ng_nodelist_mtx);
246 hook = LIST_FIRST(&ng_freehooks);
247 if (hook) {
248 LIST_REMOVE(hook, hk_hooks);
249 bcopy(&hook->hk_all, &temp, sizeof(temp));
250 bzero(hook, sizeof(struct ng_hook));
251 bcopy(&temp, &hook->hk_all, sizeof(temp));
252 mtx_unlock(&ng_nodelist_mtx);
253 hook->hk_magic = HK_MAGIC;
254 } else {
255 mtx_unlock(&ng_nodelist_mtx);
256 _NG_ALLOC_HOOK(hook);
257 if (hook) {
258 hook->hk_magic = HK_MAGIC;
259 mtx_lock(&ng_nodelist_mtx);
260 SLIST_INSERT_HEAD(&ng_allhooks, hook, hk_all);
261 mtx_unlock(&ng_nodelist_mtx);
262 }
263 }
264 return (hook);
265 }
266
267 static __inline node_p
268 ng_alloc_node(void)
269 {
270 node_p node;
271 SLIST_ENTRY(ng_node) temp;
272 mtx_lock(&ng_nodelist_mtx);
273 node = LIST_FIRST(&ng_freenodes);
274 if (node) {
275 LIST_REMOVE(node, nd_nodes);
276 bcopy(&node->nd_all, &temp, sizeof(temp));
277 bzero(node, sizeof(struct ng_node));
278 bcopy(&temp, &node->nd_all, sizeof(temp));
279 mtx_unlock(&ng_nodelist_mtx);
280 node->nd_magic = ND_MAGIC;
281 } else {
282 mtx_unlock(&ng_nodelist_mtx);
283 _NG_ALLOC_NODE(node);
284 if (node) {
285 node->nd_magic = ND_MAGIC;
286 mtx_lock(&ng_nodelist_mtx);
287 SLIST_INSERT_HEAD(&ng_allnodes, node, nd_all);
288 mtx_unlock(&ng_nodelist_mtx);
289 }
290 }
291 return (node);
292 }
293
294 #define NG_ALLOC_HOOK(hook) do { (hook) = ng_alloc_hook(); } while (0)
295 #define NG_ALLOC_NODE(node) do { (node) = ng_alloc_node(); } while (0)
296
297
298 #define NG_FREE_HOOK(hook) \
299 do { \
300 mtx_lock(&ng_nodelist_mtx); \
301 LIST_INSERT_HEAD(&ng_freehooks, hook, hk_hooks); \
302 hook->hk_magic = 0; \
303 mtx_unlock(&ng_nodelist_mtx); \
304 } while (0)
305
306 #define NG_FREE_NODE(node) \
307 do { \
308 mtx_lock(&ng_nodelist_mtx); \
309 LIST_INSERT_HEAD(&ng_freenodes, node, nd_nodes); \
310 node->nd_magic = 0; \
311 mtx_unlock(&ng_nodelist_mtx); \
312 } while (0)
313
314 #else /* NETGRAPH_DEBUG */ /*----------------------------------------------*/
315
316 #define NG_ALLOC_HOOK(hook) _NG_ALLOC_HOOK(hook)
317 #define NG_ALLOC_NODE(node) _NG_ALLOC_NODE(node)
318
319 #define NG_FREE_HOOK(hook) do { FREE((hook), M_NETGRAPH_HOOK); } while (0)
320 #define NG_FREE_NODE(node) do { FREE((node), M_NETGRAPH_NODE); } while (0)
321
322 #endif /* NETGRAPH_DEBUG */ /*----------------------------------------------*/
323
324 /* Set this to kdb_enter("X") to catch all errors as they occur */
325 #ifndef TRAP_ERROR
326 #define TRAP_ERROR()
327 #endif
328
329 static ng_ID_t nextID = 1;
330
331 #ifdef INVARIANTS
332 #define CHECK_DATA_MBUF(m) do { \
333 struct mbuf *n; \
334 int total; \
335 \
336 M_ASSERTPKTHDR(m); \
337 for (total = 0, n = (m); n != NULL; n = n->m_next) { \
338 total += n->m_len; \
339 if (n->m_nextpkt != NULL) \
340 panic("%s: m_nextpkt", __func__); \
341 } \
342 \
343 if ((m)->m_pkthdr.len != total) { \
344 panic("%s: %d != %d", \
345 __func__, (m)->m_pkthdr.len, total); \
346 } \
347 } while (0)
348 #else
349 #define CHECK_DATA_MBUF(m)
350 #endif
351
352
353 /************************************************************************
354 Parse type definitions for generic messages
355 ************************************************************************/
356
357 /* Handy structure parse type defining macro */
358 #define DEFINE_PARSE_STRUCT_TYPE(lo, up, args) \
359 static const struct ng_parse_struct_field \
360 ng_ ## lo ## _type_fields[] = NG_GENERIC_ ## up ## _INFO args; \
361 static const struct ng_parse_type ng_generic_ ## lo ## _type = { \
362 &ng_parse_struct_type, \
363 &ng_ ## lo ## _type_fields \
364 }
365
366 DEFINE_PARSE_STRUCT_TYPE(mkpeer, MKPEER, ());
367 DEFINE_PARSE_STRUCT_TYPE(connect, CONNECT, ());
368 DEFINE_PARSE_STRUCT_TYPE(name, NAME, ());
369 DEFINE_PARSE_STRUCT_TYPE(rmhook, RMHOOK, ());
370 DEFINE_PARSE_STRUCT_TYPE(nodeinfo, NODEINFO, ());
371 DEFINE_PARSE_STRUCT_TYPE(typeinfo, TYPEINFO, ());
372 DEFINE_PARSE_STRUCT_TYPE(linkinfo, LINKINFO, (&ng_generic_nodeinfo_type));
373
374 /* Get length of an array when the length is stored as a 32 bit
375 value immediately preceding the array -- as with struct namelist
376 and struct typelist. */
377 static int
378 ng_generic_list_getLength(const struct ng_parse_type *type,
379 const u_char *start, const u_char *buf)
380 {
381 return *((const u_int32_t *)(buf - 4));
382 }
383
384 /* Get length of the array of struct linkinfo inside a struct hooklist */
385 static int
386 ng_generic_linkinfo_getLength(const struct ng_parse_type *type,
387 const u_char *start, const u_char *buf)
388 {
389 const struct hooklist *hl = (const struct hooklist *)start;
390
391 return hl->nodeinfo.hooks;
392 }
393
394 /* Array type for a variable length array of struct namelist */
395 static const struct ng_parse_array_info ng_nodeinfoarray_type_info = {
396 &ng_generic_nodeinfo_type,
397 &ng_generic_list_getLength
398 };
399 static const struct ng_parse_type ng_generic_nodeinfoarray_type = {
400 &ng_parse_array_type,
401 &ng_nodeinfoarray_type_info
402 };
403
404 /* Array type for a variable length array of struct typelist */
405 static const struct ng_parse_array_info ng_typeinfoarray_type_info = {
406 &ng_generic_typeinfo_type,
407 &ng_generic_list_getLength
408 };
409 static const struct ng_parse_type ng_generic_typeinfoarray_type = {
410 &ng_parse_array_type,
411 &ng_typeinfoarray_type_info
412 };
413
414 /* Array type for array of struct linkinfo in struct hooklist */
415 static const struct ng_parse_array_info ng_generic_linkinfo_array_type_info = {
416 &ng_generic_linkinfo_type,
417 &ng_generic_linkinfo_getLength
418 };
419 static const struct ng_parse_type ng_generic_linkinfo_array_type = {
420 &ng_parse_array_type,
421 &ng_generic_linkinfo_array_type_info
422 };
423
424 DEFINE_PARSE_STRUCT_TYPE(typelist, TYPELIST, (&ng_generic_nodeinfoarray_type));
425 DEFINE_PARSE_STRUCT_TYPE(hooklist, HOOKLIST,
426 (&ng_generic_nodeinfo_type, &ng_generic_linkinfo_array_type));
427 DEFINE_PARSE_STRUCT_TYPE(listnodes, LISTNODES,
428 (&ng_generic_nodeinfoarray_type));
429
430 /* List of commands and how to convert arguments to/from ASCII */
431 static const struct ng_cmdlist ng_generic_cmds[] = {
432 {
433 NGM_GENERIC_COOKIE,
434 NGM_SHUTDOWN,
435 "shutdown",
436 NULL,
437 NULL
438 },
439 {
440 NGM_GENERIC_COOKIE,
441 NGM_MKPEER,
442 "mkpeer",
443 &ng_generic_mkpeer_type,
444 NULL
445 },
446 {
447 NGM_GENERIC_COOKIE,
448 NGM_CONNECT,
449 "connect",
450 &ng_generic_connect_type,
451 NULL
452 },
453 {
454 NGM_GENERIC_COOKIE,
455 NGM_NAME,
456 "name",
457 &ng_generic_name_type,
458 NULL
459 },
460 {
461 NGM_GENERIC_COOKIE,
462 NGM_RMHOOK,
463 "rmhook",
464 &ng_generic_rmhook_type,
465 NULL
466 },
467 {
468 NGM_GENERIC_COOKIE,
469 NGM_NODEINFO,
470 "nodeinfo",
471 NULL,
472 &ng_generic_nodeinfo_type
473 },
474 {
475 NGM_GENERIC_COOKIE,
476 NGM_LISTHOOKS,
477 "listhooks",
478 NULL,
479 &ng_generic_hooklist_type
480 },
481 {
482 NGM_GENERIC_COOKIE,
483 NGM_LISTNAMES,
484 "listnames",
485 NULL,
486 &ng_generic_listnodes_type /* same as NGM_LISTNODES */
487 },
488 {
489 NGM_GENERIC_COOKIE,
490 NGM_LISTNODES,
491 "listnodes",
492 NULL,
493 &ng_generic_listnodes_type
494 },
495 {
496 NGM_GENERIC_COOKIE,
497 NGM_LISTTYPES,
498 "listtypes",
499 NULL,
500 &ng_generic_typeinfo_type
501 },
502 {
503 NGM_GENERIC_COOKIE,
504 NGM_TEXT_CONFIG,
505 "textconfig",
506 NULL,
507 &ng_parse_string_type
508 },
509 {
510 NGM_GENERIC_COOKIE,
511 NGM_TEXT_STATUS,
512 "textstatus",
513 NULL,
514 &ng_parse_string_type
515 },
516 {
517 NGM_GENERIC_COOKIE,
518 NGM_ASCII2BINARY,
519 "ascii2binary",
520 &ng_parse_ng_mesg_type,
521 &ng_parse_ng_mesg_type
522 },
523 {
524 NGM_GENERIC_COOKIE,
525 NGM_BINARY2ASCII,
526 "binary2ascii",
527 &ng_parse_ng_mesg_type,
528 &ng_parse_ng_mesg_type
529 },
530 { 0 }
531 };
532
533 /************************************************************************
534 Node routines
535 ************************************************************************/
536
537 /*
538 * Instantiate a node of the requested type
539 */
540 int
541 ng_make_node(const char *typename, node_p *nodepp)
542 {
543 struct ng_type *type;
544 int error;
545
546 /* Check that the type makes sense */
547 if (typename == NULL) {
548 TRAP_ERROR();
549 return (EINVAL);
550 }
551
552 /* Locate the node type. If we fail we return. Do not try to load
553 * module.
554 */
555 if ((type = ng_findtype(typename)) == NULL)
556 return (ENXIO);
557
558 /*
559 * If we have a constructor, then make the node and
560 * call the constructor to do type specific initialisation.
561 */
562 if (type->constructor != NULL) {
563 if ((error = ng_make_node_common(type, nodepp)) == 0) {
564 if ((error = ((*type->constructor)(*nodepp)) != 0)) {
565 NG_NODE_UNREF(*nodepp);
566 }
567 }
568 } else {
569 /*
570 * Node has no constructor. We cannot ask for one
571 * to be made. It must be brought into existance by
572 * some external agency. The external agency should
573 * call ng_make_node_common() directly to get the
574 * netgraph part initialised.
575 */
576 TRAP_ERROR();
577 error = EINVAL;
578 }
579 return (error);
580 }
581
582 /*
583 * Generic node creation. Called by node initialisation for externally
584 * instantiated nodes (e.g. hardware, sockets, etc ).
585 * The returned node has a reference count of 1.
586 */
587 int
588 ng_make_node_common(struct ng_type *type, node_p *nodepp)
589 {
590 node_p node;
591
592 /* Require the node type to have been already installed */
593 if (ng_findtype(type->name) == NULL) {
594 TRAP_ERROR();
595 return (EINVAL);
596 }
597
598 /* Make a node and try attach it to the type */
599 NG_ALLOC_NODE(node);
600 if (node == NULL) {
601 TRAP_ERROR();
602 return (ENOMEM);
603 }
604 node->nd_type = type;
605 NG_NODE_REF(node); /* note reference */
606 type->refs++;
607
608 mtx_init(&node->nd_input_queue.q_mtx, "ng_node", NULL, MTX_SPIN);
609 node->nd_input_queue.queue = NULL;
610 node->nd_input_queue.last = &node->nd_input_queue.queue;
611 node->nd_input_queue.q_flags = 0;
612 node->nd_input_queue.q_node = node;
613
614 /* Initialize hook list for new node */
615 LIST_INIT(&node->nd_hooks);
616
617 /* Link us into the node linked list */
618 mtx_lock(&ng_nodelist_mtx);
619 LIST_INSERT_HEAD(&ng_nodelist, node, nd_nodes);
620 mtx_unlock(&ng_nodelist_mtx);
621
622
623 /* get an ID and put us in the hash chain */
624 mtx_lock(&ng_idhash_mtx);
625 for (;;) { /* wrap protection, even if silly */
626 node_p node2 = NULL;
627 node->nd_ID = nextID++; /* 137/second for 1 year before wrap */
628
629 /* Is there a problem with the new number? */
630 NG_IDHASH_FIND(node->nd_ID, node2); /* already taken? */
631 if ((node->nd_ID != 0) && (node2 == NULL)) {
632 break;
633 }
634 }
635 LIST_INSERT_HEAD(&ng_ID_hash[NG_IDHASH_FN(node->nd_ID)],
636 node, nd_idnodes);
637 mtx_unlock(&ng_idhash_mtx);
638
639 /* Done */
640 *nodepp = node;
641 return (0);
642 }
643
644 /*
645 * Forceably start the shutdown process on a node. Either call
646 * it's shutdown method, or do the default shutdown if there is
647 * no type-specific method.
648 *
649 * We can only be called form a shutdown message, so we know we have
650 * a writer lock, and therefore exclusive access. It also means
651 * that we should not be on the work queue, but we check anyhow.
652 *
653 * Persistent node types must have a type-specific method which
654 * Allocates a new node in which case, this one is irretrievably going away,
655 * or cleans up anything it needs, and just makes the node valid again,
656 * in which case we allow the node to survive.
657 *
658 * XXX We need to think of how to tell a persistant node that we
659 * REALLY need to go away because the hardware has gone or we
660 * are rebooting.... etc.
661 */
662 void
663 ng_rmnode(node_p node, hook_p dummy1, void *dummy2, int dummy3)
664 {
665 hook_p hook;
666
667 /* Check if it's already shutting down */
668 if ((node->nd_flags & NGF_CLOSING) != 0)
669 return;
670
671 if (node == &ng_deadnode) {
672 printf ("shutdown called on deadnode\n");
673 return;
674 }
675
676 /* Add an extra reference so it doesn't go away during this */
677 NG_NODE_REF(node);
678
679 /*
680 * Mark it invalid so any newcomers know not to try use it
681 * Also add our own mark so we can't recurse
682 * note that NGF_INVALID does not do this as it's also set during
683 * creation
684 */
685 node->nd_flags |= NGF_INVALID|NGF_CLOSING;
686
687 /* If node has its pre-shutdown method, then call it first*/
688 if (node->nd_type && node->nd_type->close)
689 (*node->nd_type->close)(node);
690
691 /* Notify all remaining connected nodes to disconnect */
692 while ((hook = LIST_FIRST(&node->nd_hooks)) != NULL)
693 ng_destroy_hook(hook);
694
695 /*
696 * Drain the input queue forceably.
697 * it has no hooks so what's it going to do, bleed on someone?
698 * Theoretically we came here from a queue entry that was added
699 * Just before the queue was closed, so it should be empty anyway.
700 * Also removes us from worklist if needed.
701 */
702 ng_flush_input_queue(&node->nd_input_queue);
703
704 /* Ask the type if it has anything to do in this case */
705 if (node->nd_type && node->nd_type->shutdown) {
706 (*node->nd_type->shutdown)(node);
707 if (NG_NODE_IS_VALID(node)) {
708 /*
709 * Well, blow me down if the node code hasn't declared
710 * that it doesn't want to die.
711 * Presumably it is a persistant node.
712 * If we REALLY want it to go away,
713 * e.g. hardware going away,
714 * Our caller should set NGF_REALLY_DIE in nd_flags.
715 */
716 node->nd_flags &= ~(NGF_INVALID|NGF_CLOSING);
717 NG_NODE_UNREF(node); /* Assume they still have theirs */
718 return;
719 }
720 } else { /* do the default thing */
721 NG_NODE_UNREF(node);
722 }
723
724 ng_unname(node); /* basically a NOP these days */
725
726 /*
727 * Remove extra reference, possibly the last
728 * Possible other holders of references may include
729 * timeout callouts, but theoretically the node's supposed to
730 * have cancelled them. Possibly hardware dependencies may
731 * force a driver to 'linger' with a reference.
732 */
733 NG_NODE_UNREF(node);
734 }
735
736 /*
737 * Remove a reference to the node, possibly the last.
738 * deadnode always acts as it it were the last.
739 */
740 int
741 ng_unref_node(node_p node)
742 {
743 int v;
744
745 if (node == &ng_deadnode) {
746 return (0);
747 }
748
749 do {
750 v = node->nd_refs - 1;
751 } while (! atomic_cmpset_int(&node->nd_refs, v + 1, v));
752
753 if (v == 0) { /* we were the last */
754
755 mtx_lock(&ng_nodelist_mtx);
756 node->nd_type->refs--; /* XXX maybe should get types lock? */
757 LIST_REMOVE(node, nd_nodes);
758 mtx_unlock(&ng_nodelist_mtx);
759
760 mtx_lock(&ng_idhash_mtx);
761 LIST_REMOVE(node, nd_idnodes);
762 mtx_unlock(&ng_idhash_mtx);
763
764 mtx_destroy(&node->nd_input_queue.q_mtx);
765 NG_FREE_NODE(node);
766 }
767 return (v);
768 }
769
770 /************************************************************************
771 Node ID handling
772 ************************************************************************/
773 static node_p
774 ng_ID2noderef(ng_ID_t ID)
775 {
776 node_p node;
777 mtx_lock(&ng_idhash_mtx);
778 NG_IDHASH_FIND(ID, node);
779 if(node)
780 NG_NODE_REF(node);
781 mtx_unlock(&ng_idhash_mtx);
782 return(node);
783 }
784
785 ng_ID_t
786 ng_node2ID(node_p node)
787 {
788 return (node ? NG_NODE_ID(node) : 0);
789 }
790
791 /************************************************************************
792 Node name handling
793 ************************************************************************/
794
795 /*
796 * Assign a node a name. Once assigned, the name cannot be changed.
797 */
798 int
799 ng_name_node(node_p node, const char *name)
800 {
801 int i;
802 node_p node2;
803
804 /* Check the name is valid */
805 for (i = 0; i < NG_NODESIZ; i++) {
806 if (name[i] == '\0' || name[i] == '.' || name[i] == ':')
807 break;
808 }
809 if (i == 0 || name[i] != '\0') {
810 TRAP_ERROR();
811 return (EINVAL);
812 }
813 if (ng_decodeidname(name) != 0) { /* valid IDs not allowed here */
814 TRAP_ERROR();
815 return (EINVAL);
816 }
817
818 /* Check the name isn't already being used */
819 if ((node2 = ng_name2noderef(node, name)) != NULL) {
820 NG_NODE_UNREF(node2);
821 TRAP_ERROR();
822 return (EADDRINUSE);
823 }
824
825 /* copy it */
826 strlcpy(NG_NODE_NAME(node), name, NG_NODESIZ);
827
828 return (0);
829 }
830
831 /*
832 * Find a node by absolute name. The name should NOT end with ':'
833 * The name "." means "this node" and "[xxx]" means "the node
834 * with ID (ie, at address) xxx".
835 *
836 * Returns the node if found, else NULL.
837 * Eventually should add something faster than a sequential search.
838 * Note it aquires a reference on the node so you can be sure it's still there.
839 */
840 node_p
841 ng_name2noderef(node_p here, const char *name)
842 {
843 node_p node;
844 ng_ID_t temp;
845
846 /* "." means "this node" */
847 if (strcmp(name, ".") == 0) {
848 NG_NODE_REF(here);
849 return(here);
850 }
851
852 /* Check for name-by-ID */
853 if ((temp = ng_decodeidname(name)) != 0) {
854 return (ng_ID2noderef(temp));
855 }
856
857 /* Find node by name */
858 mtx_lock(&ng_nodelist_mtx);
859 LIST_FOREACH(node, &ng_nodelist, nd_nodes) {
860 if (NG_NODE_IS_VALID(node)
861 && NG_NODE_HAS_NAME(node)
862 && (strcmp(NG_NODE_NAME(node), name) == 0)) {
863 break;
864 }
865 }
866 if (node)
867 NG_NODE_REF(node);
868 mtx_unlock(&ng_nodelist_mtx);
869 return (node);
870 }
871
872 /*
873 * Decode an ID name, eg. "[f03034de]". Returns 0 if the
874 * string is not valid, otherwise returns the value.
875 */
876 static ng_ID_t
877 ng_decodeidname(const char *name)
878 {
879 const int len = strlen(name);
880 char *eptr;
881 u_long val;
882
883 /* Check for proper length, brackets, no leading junk */
884 if ((len < 3)
885 || (name[0] != '[')
886 || (name[len - 1] != ']')
887 || (!isxdigit(name[1]))) {
888 return ((ng_ID_t)0);
889 }
890
891 /* Decode number */
892 val = strtoul(name + 1, &eptr, 16);
893 if ((eptr - name != len - 1)
894 || (val == ULONG_MAX)
895 || (val == 0)) {
896 return ((ng_ID_t)0);
897 }
898 return (ng_ID_t)val;
899 }
900
901 /*
902 * Remove a name from a node. This should only be called
903 * when shutting down and removing the node.
904 * IF we allow name changing this may be more resurected.
905 */
906 void
907 ng_unname(node_p node)
908 {
909 }
910
911 /************************************************************************
912 Hook routines
913 Names are not optional. Hooks are always connected, except for a
914 brief moment within these routines. On invalidation or during creation
915 they are connected to the 'dead' hook.
916 ************************************************************************/
917
918 /*
919 * Remove a hook reference
920 */
921 void
922 ng_unref_hook(hook_p hook)
923 {
924 int v;
925
926 if (hook == &ng_deadhook) {
927 return;
928 }
929 do {
930 v = hook->hk_refs;
931 } while (! atomic_cmpset_int(&hook->hk_refs, v, v - 1));
932
933 if (v == 1) { /* we were the last */
934 if (_NG_HOOK_NODE(hook)) { /* it'll probably be ng_deadnode */
935 _NG_NODE_UNREF((_NG_HOOK_NODE(hook)));
936 hook->hk_node = NULL;
937 }
938 NG_FREE_HOOK(hook);
939 }
940 }
941
942 /*
943 * Add an unconnected hook to a node. Only used internally.
944 * Assumes node is locked. (XXX not yet true )
945 */
946 static int
947 ng_add_hook(node_p node, const char *name, hook_p *hookp)
948 {
949 hook_p hook;
950 int error = 0;
951
952 /* Check that the given name is good */
953 if (name == NULL) {
954 TRAP_ERROR();
955 return (EINVAL);
956 }
957 if (ng_findhook(node, name) != NULL) {
958 TRAP_ERROR();
959 return (EEXIST);
960 }
961
962 /* Allocate the hook and link it up */
963 NG_ALLOC_HOOK(hook);
964 if (hook == NULL) {
965 TRAP_ERROR();
966 return (ENOMEM);
967 }
968 hook->hk_refs = 1; /* add a reference for us to return */
969 hook->hk_flags = HK_INVALID;
970 hook->hk_peer = &ng_deadhook; /* start off this way */
971 hook->hk_node = node;
972 NG_NODE_REF(node); /* each hook counts as a reference */
973
974 /* Set hook name */
975 strlcpy(NG_HOOK_NAME(hook), name, NG_HOOKSIZ);
976
977 /*
978 * Check if the node type code has something to say about it
979 * If it fails, the unref of the hook will also unref the node.
980 */
981 if (node->nd_type->newhook != NULL) {
982 if ((error = (*node->nd_type->newhook)(node, hook, name))) {
983 NG_HOOK_UNREF(hook); /* this frees the hook */
984 return (error);
985 }
986 }
987 /*
988 * The 'type' agrees so far, so go ahead and link it in.
989 * We'll ask again later when we actually connect the hooks.
990 */
991 LIST_INSERT_HEAD(&node->nd_hooks, hook, hk_hooks);
992 node->nd_numhooks++;
993 NG_HOOK_REF(hook); /* one for the node */
994
995 if (hookp)
996 *hookp = hook;
997 return (0);
998 }
999
1000 /*
1001 * Find a hook
1002 *
1003 * Node types may supply their own optimized routines for finding
1004 * hooks. If none is supplied, we just do a linear search.
1005 * XXX Possibly we should add a reference to the hook?
1006 */
1007 hook_p
1008 ng_findhook(node_p node, const char *name)
1009 {
1010 hook_p hook;
1011
1012 if (node->nd_type->findhook != NULL)
1013 return (*node->nd_type->findhook)(node, name);
1014 LIST_FOREACH(hook, &node->nd_hooks, hk_hooks) {
1015 if (NG_HOOK_IS_VALID(hook)
1016 && (strcmp(NG_HOOK_NAME(hook), name) == 0))
1017 return (hook);
1018 }
1019 return (NULL);
1020 }
1021
1022 /*
1023 * Destroy a hook
1024 *
1025 * As hooks are always attached, this really destroys two hooks.
1026 * The one given, and the one attached to it. Disconnect the hooks
1027 * from each other first. We reconnect the peer hook to the 'dead'
1028 * hook so that it can still exist after we depart. We then
1029 * send the peer its own destroy message. This ensures that we only
1030 * interact with the peer's structures when it is locked processing that
1031 * message. We hold a reference to the peer hook so we are guaranteed that
1032 * the peer hook and node are still going to exist until
1033 * we are finished there as the hook holds a ref on the node.
1034 * We run this same code again on the peer hook, but that time it is already
1035 * attached to the 'dead' hook.
1036 *
1037 * This routine is called at all stages of hook creation
1038 * on error detection and must be able to handle any such stage.
1039 */
1040 void
1041 ng_destroy_hook(hook_p hook)
1042 {
1043 hook_p peer;
1044 node_p node;
1045
1046 if (hook == &ng_deadhook) { /* better safe than sorry */
1047 printf("ng_destroy_hook called on deadhook\n");
1048 return;
1049 }
1050
1051 /*
1052 * Protect divorce process with mutex, to avoid races on
1053 * simultaneous disconnect.
1054 */
1055 mtx_lock(&ng_topo_mtx);
1056
1057 hook->hk_flags |= HK_INVALID;
1058
1059 peer = NG_HOOK_PEER(hook);
1060 node = NG_HOOK_NODE(hook);
1061
1062 if (peer && (peer != &ng_deadhook)) {
1063 /*
1064 * Set the peer to point to ng_deadhook
1065 * from this moment on we are effectively independent it.
1066 * send it an rmhook message of it's own.
1067 */
1068 peer->hk_peer = &ng_deadhook; /* They no longer know us */
1069 hook->hk_peer = &ng_deadhook; /* Nor us, them */
1070 if (NG_HOOK_NODE(peer) == &ng_deadnode) {
1071 /*
1072 * If it's already divorced from a node,
1073 * just free it.
1074 */
1075 mtx_unlock(&ng_topo_mtx);
1076 } else {
1077 mtx_unlock(&ng_topo_mtx);
1078 ng_rmhook_self(peer); /* Send it a surprise */
1079 }
1080 NG_HOOK_UNREF(peer); /* account for peer link */
1081 NG_HOOK_UNREF(hook); /* account for peer link */
1082 } else
1083 mtx_unlock(&ng_topo_mtx);
1084
1085 mtx_assert(&ng_topo_mtx, MA_NOTOWNED);
1086
1087 /*
1088 * Remove the hook from the node's list to avoid possible recursion
1089 * in case the disconnection results in node shutdown.
1090 */
1091 if (node == &ng_deadnode) { /* happens if called from ng_con_nodes() */
1092 return;
1093 }
1094 LIST_REMOVE(hook, hk_hooks);
1095 node->nd_numhooks--;
1096 if (node->nd_type->disconnect) {
1097 /*
1098 * The type handler may elect to destroy the node so don't
1099 * trust its existance after this point. (except
1100 * that we still hold a reference on it. (which we
1101 * inherrited from the hook we are destroying)
1102 */
1103 (*node->nd_type->disconnect) (hook);
1104 }
1105
1106 /*
1107 * Note that because we will point to ng_deadnode, the original node
1108 * is not decremented automatically so we do that manually.
1109 */
1110 _NG_HOOK_NODE(hook) = &ng_deadnode;
1111 NG_NODE_UNREF(node); /* We no longer point to it so adjust count */
1112 NG_HOOK_UNREF(hook); /* Account for linkage (in list) to node */
1113 }
1114
1115 /*
1116 * Take two hooks on a node and merge the connection so that the given node
1117 * is effectively bypassed.
1118 */
1119 int
1120 ng_bypass(hook_p hook1, hook_p hook2)
1121 {
1122 if (hook1->hk_node != hook2->hk_node) {
1123 TRAP_ERROR();
1124 return (EINVAL);
1125 }
1126 hook1->hk_peer->hk_peer = hook2->hk_peer;
1127 hook2->hk_peer->hk_peer = hook1->hk_peer;
1128
1129 hook1->hk_peer = &ng_deadhook;
1130 hook2->hk_peer = &ng_deadhook;
1131
1132 /* XXX If we ever cache methods on hooks update them as well */
1133 ng_destroy_hook(hook1);
1134 ng_destroy_hook(hook2);
1135 return (0);
1136 }
1137
1138 /*
1139 * Install a new netgraph type
1140 */
1141 int
1142 ng_newtype(struct ng_type *tp)
1143 {
1144 const size_t namelen = strlen(tp->name);
1145
1146 /* Check version and type name fields */
1147 if ((tp->version != NG_ABI_VERSION)
1148 || (namelen == 0)
1149 || (namelen >= NG_TYPESIZ)) {
1150 TRAP_ERROR();
1151 if (tp->version != NG_ABI_VERSION) {
1152 printf("Netgraph: Node type rejected. ABI mismatch. Suggest recompile\n");
1153 }
1154 return (EINVAL);
1155 }
1156
1157 /* Check for name collision */
1158 if (ng_findtype(tp->name) != NULL) {
1159 TRAP_ERROR();
1160 return (EEXIST);
1161 }
1162
1163
1164 /* Link in new type */
1165 mtx_lock(&ng_typelist_mtx);
1166 LIST_INSERT_HEAD(&ng_typelist, tp, types);
1167 tp->refs = 1; /* first ref is linked list */
1168 mtx_unlock(&ng_typelist_mtx);
1169 return (0);
1170 }
1171
1172 /*
1173 * unlink a netgraph type
1174 * If no examples exist
1175 */
1176 int
1177 ng_rmtype(struct ng_type *tp)
1178 {
1179 /* Check for name collision */
1180 if (tp->refs != 1) {
1181 TRAP_ERROR();
1182 return (EBUSY);
1183 }
1184
1185 /* Unlink type */
1186 mtx_lock(&ng_typelist_mtx);
1187 LIST_REMOVE(tp, types);
1188 mtx_unlock(&ng_typelist_mtx);
1189 return (0);
1190 }
1191
1192 /*
1193 * Look for a type of the name given
1194 */
1195 struct ng_type *
1196 ng_findtype(const char *typename)
1197 {
1198 struct ng_type *type;
1199
1200 mtx_lock(&ng_typelist_mtx);
1201 LIST_FOREACH(type, &ng_typelist, types) {
1202 if (strcmp(type->name, typename) == 0)
1203 break;
1204 }
1205 mtx_unlock(&ng_typelist_mtx);
1206 return (type);
1207 }
1208
1209 /************************************************************************
1210 Composite routines
1211 ************************************************************************/
1212 /*
1213 * Connect two nodes using the specified hooks, using queued functions.
1214 */
1215 static void
1216 ng_con_part3(node_p node, hook_p hook, void *arg1, int arg2)
1217 {
1218
1219 /*
1220 * When we run, we know that the node 'node' is locked for us.
1221 * Our caller has a reference on the hook.
1222 * Our caller has a reference on the node.
1223 * (In this case our caller is ng_apply_item() ).
1224 * The peer hook has a reference on the hook.
1225 * We are all set up except for the final call to the node, and
1226 * the clearing of the INVALID flag.
1227 */
1228 if (NG_HOOK_NODE(hook) == &ng_deadnode) {
1229 /*
1230 * The node must have been freed again since we last visited
1231 * here. ng_destry_hook() has this effect but nothing else does.
1232 * We should just release our references and
1233 * free anything we can think of.
1234 * Since we know it's been destroyed, and it's our caller
1235 * that holds the references, just return.
1236 */
1237 return ;
1238 }
1239 if (hook->hk_node->nd_type->connect) {
1240 if ((*hook->hk_node->nd_type->connect) (hook)) {
1241 ng_destroy_hook(hook); /* also zaps peer */
1242 printf("failed in ng_con_part3()\n");
1243 return ;
1244 }
1245 }
1246 /*
1247 * XXX this is wrong for SMP. Possibly we need
1248 * to separate out 'create' and 'invalid' flags.
1249 * should only set flags on hooks we have locked under our node.
1250 */
1251 hook->hk_flags &= ~HK_INVALID;
1252 return ;
1253 }
1254
1255 static void
1256 ng_con_part2(node_p node, hook_p hook, void *arg1, int arg2)
1257 {
1258 hook_p peer;
1259
1260 /*
1261 * When we run, we know that the node 'node' is locked for us.
1262 * Our caller has a reference on the hook.
1263 * Our caller has a reference on the node.
1264 * (In this case our caller is ng_apply_item() ).
1265 * The peer hook has a reference on the hook.
1266 * our node pointer points to the 'dead' node.
1267 * First check the hook name is unique.
1268 * Should not happen because we checked before queueing this.
1269 */
1270 if (ng_findhook(node, NG_HOOK_NAME(hook)) != NULL) {
1271 TRAP_ERROR();
1272 ng_destroy_hook(hook); /* should destroy peer too */
1273 printf("failed in ng_con_part2()\n");
1274 return ;
1275 }
1276 /*
1277 * Check if the node type code has something to say about it
1278 * If it fails, the unref of the hook will also unref the attached node,
1279 * however since that node is 'ng_deadnode' this will do nothing.
1280 * The peer hook will also be destroyed.
1281 */
1282 if (node->nd_type->newhook != NULL) {
1283 if ((*node->nd_type->newhook)(node, hook, hook->hk_name)) {
1284 ng_destroy_hook(hook); /* should destroy peer too */
1285 printf("failed in ng_con_part2()\n");
1286 return ;
1287 }
1288 }
1289
1290 /*
1291 * The 'type' agrees so far, so go ahead and link it in.
1292 * We'll ask again later when we actually connect the hooks.
1293 */
1294 hook->hk_node = node; /* just overwrite ng_deadnode */
1295 NG_NODE_REF(node); /* each hook counts as a reference */
1296 LIST_INSERT_HEAD(&node->nd_hooks, hook, hk_hooks);
1297 node->nd_numhooks++;
1298 NG_HOOK_REF(hook); /* one for the node */
1299
1300 /*
1301 * We now have a symetrical situation, where both hooks have been
1302 * linked to their nodes, the newhook methods have been called
1303 * And the references are all correct. The hooks are still marked
1304 * as invalid, as we have not called the 'connect' methods
1305 * yet.
1306 * We can call the local one immediatly as we have the
1307 * node locked, but we need to queue the remote one.
1308 */
1309 if (hook->hk_node->nd_type->connect) {
1310 if ((*hook->hk_node->nd_type->connect) (hook)) {
1311 ng_destroy_hook(hook); /* also zaps peer */
1312 printf("failed in ng_con_part2(A)\n");
1313 return ;
1314 }
1315 }
1316
1317 /*
1318 * Acquire topo mutex to avoid race with ng_destroy_hook().
1319 */
1320 mtx_lock(&ng_topo_mtx);
1321 peer = hook->hk_peer;
1322 if (peer == &ng_deadhook) {
1323 mtx_unlock(&ng_topo_mtx);
1324 printf("failed in ng_con_part2(B)\n");
1325 ng_destroy_hook(hook);
1326 return ;
1327 }
1328 mtx_unlock(&ng_topo_mtx);
1329
1330 if (ng_send_fn(peer->hk_node, peer, &ng_con_part3, arg1, arg2)) {
1331 printf("failed in ng_con_part2(C)\n");
1332 ng_destroy_hook(hook); /* also zaps peer */
1333 return ;
1334 }
1335 hook->hk_flags &= ~HK_INVALID; /* need both to be able to work */
1336 return ;
1337 }
1338
1339 /*
1340 * Connect this node with another node. We assume that this node is
1341 * currently locked, as we are only called from an NGM_CONNECT message.
1342 */
1343 static int
1344 ng_con_nodes(node_p node, const char *name, node_p node2, const char *name2)
1345 {
1346 int error;
1347 hook_p hook;
1348 hook_p hook2;
1349
1350 if (ng_findhook(node2, name2) != NULL) {
1351 return(EEXIST);
1352 }
1353 if ((error = ng_add_hook(node, name, &hook))) /* gives us a ref */
1354 return (error);
1355 /* Allocate the other hook and link it up */
1356 NG_ALLOC_HOOK(hook2);
1357 if (hook2 == NULL) {
1358 TRAP_ERROR();
1359 ng_destroy_hook(hook); /* XXX check ref counts so far */
1360 NG_HOOK_UNREF(hook); /* including our ref */
1361 return (ENOMEM);
1362 }
1363 hook2->hk_refs = 1; /* start with a reference for us. */
1364 hook2->hk_flags = HK_INVALID;
1365 hook2->hk_peer = hook; /* Link the two together */
1366 hook->hk_peer = hook2;
1367 NG_HOOK_REF(hook); /* Add a ref for the peer to each*/
1368 NG_HOOK_REF(hook2);
1369 hook2->hk_node = &ng_deadnode;
1370 strlcpy(NG_HOOK_NAME(hook2), name2, NG_HOOKSIZ);
1371
1372 /*
1373 * Queue the function above.
1374 * Procesing continues in that function in the lock context of
1375 * the other node.
1376 */
1377 ng_send_fn(node2, hook2, &ng_con_part2, NULL, 0);
1378
1379 NG_HOOK_UNREF(hook); /* Let each hook go if it wants to */
1380 NG_HOOK_UNREF(hook2);
1381 return (0);
1382 }
1383
1384 /*
1385 * Make a peer and connect.
1386 * We assume that the local node is locked.
1387 * The new node probably doesn't need a lock until
1388 * it has a hook, because it cannot really have any work until then,
1389 * but we should think about it a bit more.
1390 *
1391 * The problem may come if the other node also fires up
1392 * some hardware or a timer or some other source of activation,
1393 * also it may already get a command msg via it's ID.
1394 *
1395 * We could use the same method as ng_con_nodes() but we'd have
1396 * to add ability to remove the node when failing. (Not hard, just
1397 * make arg1 point to the node to remove).
1398 * Unless of course we just ignore failure to connect and leave
1399 * an unconnected node?
1400 */
1401 static int
1402 ng_mkpeer(node_p node, const char *name, const char *name2, char *type)
1403 {
1404 node_p node2;
1405 hook_p hook1, hook2;
1406 int error;
1407
1408 if ((error = ng_make_node(type, &node2))) {
1409 return (error);
1410 }
1411
1412 if ((error = ng_add_hook(node, name, &hook1))) { /* gives us a ref */
1413 ng_rmnode(node2, NULL, NULL, 0);
1414 return (error);
1415 }
1416
1417 if ((error = ng_add_hook(node2, name2, &hook2))) {
1418 ng_rmnode(node2, NULL, NULL, 0);
1419 ng_destroy_hook(hook1);
1420 NG_HOOK_UNREF(hook1);
1421 return (error);
1422 }
1423
1424 /*
1425 * Actually link the two hooks together.
1426 */
1427 hook1->hk_peer = hook2;
1428 hook2->hk_peer = hook1;
1429
1430 /* Each hook is referenced by the other */
1431 NG_HOOK_REF(hook1);
1432 NG_HOOK_REF(hook2);
1433
1434 /* Give each node the opportunity to veto the pending connection */
1435 if (hook1->hk_node->nd_type->connect) {
1436 error = (*hook1->hk_node->nd_type->connect) (hook1);
1437 }
1438
1439 if ((error == 0) && hook2->hk_node->nd_type->connect) {
1440 error = (*hook2->hk_node->nd_type->connect) (hook2);
1441
1442 }
1443
1444 /*
1445 * drop the references we were holding on the two hooks.
1446 */
1447 if (error) {
1448 ng_destroy_hook(hook2); /* also zaps hook1 */
1449 ng_rmnode(node2, NULL, NULL, 0);
1450 } else {
1451 /* As a last act, allow the hooks to be used */
1452 hook1->hk_flags &= ~HK_INVALID;
1453 hook2->hk_flags &= ~HK_INVALID;
1454 }
1455 NG_HOOK_UNREF(hook1);
1456 NG_HOOK_UNREF(hook2);
1457 return (error);
1458 }
1459
1460 /************************************************************************
1461 Utility routines to send self messages
1462 ************************************************************************/
1463
1464 /* Shut this node down as soon as everyone is clear of it */
1465 /* Should add arg "immediatly" to jump the queue */
1466 int
1467 ng_rmnode_self(node_p node)
1468 {
1469 int error;
1470
1471 if (node == &ng_deadnode)
1472 return (0);
1473 node->nd_flags |= NGF_INVALID;
1474 if (node->nd_flags & NGF_CLOSING)
1475 return (0);
1476
1477 error = ng_send_fn(node, NULL, &ng_rmnode, NULL, 0);
1478 return (error);
1479 }
1480
1481 static void
1482 ng_rmhook_part2(node_p node, hook_p hook, void *arg1, int arg2)
1483 {
1484 ng_destroy_hook(hook);
1485 return ;
1486 }
1487
1488 int
1489 ng_rmhook_self(hook_p hook)
1490 {
1491 int error;
1492 node_p node = NG_HOOK_NODE(hook);
1493
1494 if (node == &ng_deadnode)
1495 return (0);
1496
1497 error = ng_send_fn(node, hook, &ng_rmhook_part2, NULL, 0);
1498 return (error);
1499 }
1500
1501 /***********************************************************************
1502 * Parse and verify a string of the form: <NODE:><PATH>
1503 *
1504 * Such a string can refer to a specific node or a specific hook
1505 * on a specific node, depending on how you look at it. In the
1506 * latter case, the PATH component must not end in a dot.
1507 *
1508 * Both <NODE:> and <PATH> are optional. The <PATH> is a string
1509 * of hook names separated by dots. This breaks out the original
1510 * string, setting *nodep to "NODE" (or NULL if none) and *pathp
1511 * to "PATH" (or NULL if degenerate). Also, *hookp will point to
1512 * the final hook component of <PATH>, if any, otherwise NULL.
1513 *
1514 * This returns -1 if the path is malformed. The char ** are optional.
1515 ***********************************************************************/
1516 int
1517 ng_path_parse(char *addr, char **nodep, char **pathp, char **hookp)
1518 {
1519 char *node, *path, *hook;
1520 int k;
1521
1522 /*
1523 * Extract absolute NODE, if any
1524 */
1525 for (path = addr; *path && *path != ':'; path++);
1526 if (*path) {
1527 node = addr; /* Here's the NODE */
1528 *path++ = '\0'; /* Here's the PATH */
1529
1530 /* Node name must not be empty */
1531 if (!*node)
1532 return -1;
1533
1534 /* A name of "." is OK; otherwise '.' not allowed */
1535 if (strcmp(node, ".") != 0) {
1536 for (k = 0; node[k]; k++)
1537 if (node[k] == '.')
1538 return -1;
1539 }
1540 } else {
1541 node = NULL; /* No absolute NODE */
1542 path = addr; /* Here's the PATH */
1543 }
1544
1545 /* Snoop for illegal characters in PATH */
1546 for (k = 0; path[k]; k++)
1547 if (path[k] == ':')
1548 return -1;
1549
1550 /* Check for no repeated dots in PATH */
1551 for (k = 0; path[k]; k++)
1552 if (path[k] == '.' && path[k + 1] == '.')
1553 return -1;
1554
1555 /* Remove extra (degenerate) dots from beginning or end of PATH */
1556 if (path[0] == '.')
1557 path++;
1558 if (*path && path[strlen(path) - 1] == '.')
1559 path[strlen(path) - 1] = 0;
1560
1561 /* If PATH has a dot, then we're not talking about a hook */
1562 if (*path) {
1563 for (hook = path, k = 0; path[k]; k++)
1564 if (path[k] == '.') {
1565 hook = NULL;
1566 break;
1567 }
1568 } else
1569 path = hook = NULL;
1570
1571 /* Done */
1572 if (nodep)
1573 *nodep = node;
1574 if (pathp)
1575 *pathp = path;
1576 if (hookp)
1577 *hookp = hook;
1578 return (0);
1579 }
1580
1581 /*
1582 * Given a path, which may be absolute or relative, and a starting node,
1583 * return the destination node.
1584 */
1585 int
1586 ng_path2noderef(node_p here, const char *address,
1587 node_p *destp, hook_p *lasthook)
1588 {
1589 char fullpath[NG_PATHSIZ];
1590 char *nodename, *path, pbuf[2];
1591 node_p node, oldnode;
1592 char *cp;
1593 hook_p hook = NULL;
1594
1595 /* Initialize */
1596 if (destp == NULL) {
1597 TRAP_ERROR();
1598 return EINVAL;
1599 }
1600 *destp = NULL;
1601
1602 /* Make a writable copy of address for ng_path_parse() */
1603 strncpy(fullpath, address, sizeof(fullpath) - 1);
1604 fullpath[sizeof(fullpath) - 1] = '\0';
1605
1606 /* Parse out node and sequence of hooks */
1607 if (ng_path_parse(fullpath, &nodename, &path, NULL) < 0) {
1608 TRAP_ERROR();
1609 return EINVAL;
1610 }
1611 if (path == NULL) {
1612 pbuf[0] = '.'; /* Needs to be writable */
1613 pbuf[1] = '\0';
1614 path = pbuf;
1615 }
1616
1617 /*
1618 * For an absolute address, jump to the starting node.
1619 * Note that this holds a reference on the node for us.
1620 * Don't forget to drop the reference if we don't need it.
1621 */
1622 if (nodename) {
1623 node = ng_name2noderef(here, nodename);
1624 if (node == NULL) {
1625 TRAP_ERROR();
1626 return (ENOENT);
1627 }
1628 } else {
1629 if (here == NULL) {
1630 TRAP_ERROR();
1631 return (EINVAL);
1632 }
1633 node = here;
1634 NG_NODE_REF(node);
1635 }
1636
1637 /*
1638 * Now follow the sequence of hooks
1639 * XXX
1640 * We actually cannot guarantee that the sequence
1641 * is not being demolished as we crawl along it
1642 * without extra-ordinary locking etc.
1643 * So this is a bit dodgy to say the least.
1644 * We can probably hold up some things by holding
1645 * the nodelist mutex for the time of this
1646 * crawl if we wanted.. At least that way we wouldn't have to
1647 * worry about the nodes dissappearing, but the hooks would still
1648 * be a problem.
1649 */
1650 for (cp = path; node != NULL && *cp != '\0'; ) {
1651 char *segment;
1652
1653 /*
1654 * Break out the next path segment. Replace the dot we just
1655 * found with a NUL; "cp" points to the next segment (or the
1656 * NUL at the end).
1657 */
1658 for (segment = cp; *cp != '\0'; cp++) {
1659 if (*cp == '.') {
1660 *cp++ = '\0';
1661 break;
1662 }
1663 }
1664
1665 /* Empty segment */
1666 if (*segment == '\0')
1667 continue;
1668
1669 /* We have a segment, so look for a hook by that name */
1670 hook = ng_findhook(node, segment);
1671
1672 /* Can't get there from here... */
1673 if (hook == NULL
1674 || NG_HOOK_PEER(hook) == NULL
1675 || NG_HOOK_NOT_VALID(hook)
1676 || NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook))) {
1677 TRAP_ERROR();
1678 NG_NODE_UNREF(node);
1679 #if 0
1680 printf("hooknotvalid %s %s %d %d %d %d ",
1681 path,
1682 segment,
1683 hook == NULL,
1684 NG_HOOK_PEER(hook) == NULL,
1685 NG_HOOK_NOT_VALID(hook),
1686 NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook)));
1687 #endif
1688 return (ENOENT);
1689 }
1690
1691 /*
1692 * Hop on over to the next node
1693 * XXX
1694 * Big race conditions here as hooks and nodes go away
1695 * *** Idea.. store an ng_ID_t in each hook and use that
1696 * instead of the direct hook in this crawl?
1697 */
1698 oldnode = node;
1699 if ((node = NG_PEER_NODE(hook)))
1700 NG_NODE_REF(node); /* XXX RACE */
1701 NG_NODE_UNREF(oldnode); /* XXX another race */
1702 if (NG_NODE_NOT_VALID(node)) {
1703 NG_NODE_UNREF(node); /* XXX more races */
1704 node = NULL;
1705 }
1706 }
1707
1708 /* If node somehow missing, fail here (probably this is not needed) */
1709 if (node == NULL) {
1710 TRAP_ERROR();
1711 return (ENXIO);
1712 }
1713
1714 /* Done */
1715 *destp = node;
1716 if (lasthook != NULL)
1717 *lasthook = (hook ? NG_HOOK_PEER(hook) : NULL);
1718 return (0);
1719 }
1720
1721 /***************************************************************\
1722 * Input queue handling.
1723 * All activities are submitted to the node via the input queue
1724 * which implements a multiple-reader/single-writer gate.
1725 * Items which cannot be handled immeditly are queued.
1726 *
1727 * read-write queue locking inline functions *
1728 \***************************************************************/
1729
1730 static __inline item_p ng_dequeue(struct ng_queue * ngq, int *rw);
1731 static __inline item_p ng_acquire_read(struct ng_queue * ngq,
1732 item_p item);
1733 static __inline item_p ng_acquire_write(struct ng_queue * ngq,
1734 item_p item);
1735 static __inline void ng_leave_read(struct ng_queue * ngq);
1736 static __inline void ng_leave_write(struct ng_queue * ngq);
1737 static __inline void ng_queue_rw(struct ng_queue * ngq,
1738 item_p item, int rw);
1739
1740 /*
1741 * Definition of the bits fields in the ng_queue flag word.
1742 * Defined here rather than in netgraph.h because no-one should fiddle
1743 * with them.
1744 *
1745 * The ordering here may be important! don't shuffle these.
1746 */
1747 /*-
1748 Safety Barrier--------+ (adjustable to suit taste) (not used yet)
1749 |
1750 V
1751 +-------+-------+-------+-------+-------+-------+-------+-------+
1752 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
1753 | |A|c|t|i|v|e| |R|e|a|d|e|r| |C|o|u|n|t| | | | | | | | | |P|A|
1754 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |O|W|
1755 +-------+-------+-------+-------+-------+-------+-------+-------+
1756 \___________________________ ____________________________/ | |
1757 V | |
1758 [active reader count] | |
1759 | |
1760 Operation Pending -------------------------------+ |
1761 |
1762 Active Writer ---------------------------------------+
1763
1764
1765 */
1766 #define WRITER_ACTIVE 0x00000001
1767 #define OP_PENDING 0x00000002
1768 #define READER_INCREMENT 0x00000004
1769 #define READER_MASK 0xfffffffc /* Not valid if WRITER_ACTIVE is set */
1770 #define SAFETY_BARRIER 0x00100000 /* 128K items queued should be enough */
1771
1772 /* Defines of more elaborate states on the queue */
1773 /* Mask of bits a new read cares about */
1774 #define NGQ_RMASK (WRITER_ACTIVE|OP_PENDING)
1775
1776 /* Mask of bits a new write cares about */
1777 #define NGQ_WMASK (NGQ_RMASK|READER_MASK)
1778
1779 /* Test to decide if there is something on the queue. */
1780 #define QUEUE_ACTIVE(QP) ((QP)->q_flags & OP_PENDING)
1781
1782 /* How to decide what the next queued item is. */
1783 #define HEAD_IS_READER(QP) NGI_QUEUED_READER((QP)->queue)
1784 #define HEAD_IS_WRITER(QP) NGI_QUEUED_WRITER((QP)->queue) /* notused */
1785
1786 /* Read the status to decide if the next item on the queue can now run. */
1787 #define QUEUED_READER_CAN_PROCEED(QP) \
1788 (((QP)->q_flags & (NGQ_RMASK & ~OP_PENDING)) == 0)
1789 #define QUEUED_WRITER_CAN_PROCEED(QP) \
1790 (((QP)->q_flags & (NGQ_WMASK & ~OP_PENDING)) == 0)
1791
1792 /* Is there a chance of getting ANY work off the queue? */
1793 #define NEXT_QUEUED_ITEM_CAN_PROCEED(QP) \
1794 (QUEUE_ACTIVE(QP) && \
1795 ((HEAD_IS_READER(QP)) ? QUEUED_READER_CAN_PROCEED(QP) : \
1796 QUEUED_WRITER_CAN_PROCEED(QP)))
1797
1798
1799 #define NGQRW_R 0
1800 #define NGQRW_W 1
1801
1802 /*
1803 * Taking into account the current state of the queue and node, possibly take
1804 * the next entry off the queue and return it. Return NULL if there was
1805 * nothing we could return, either because there really was nothing there, or
1806 * because the node was in a state where it cannot yet process the next item
1807 * on the queue.
1808 *
1809 * This MUST MUST MUST be called with the mutex held.
1810 */
1811 static __inline item_p
1812 ng_dequeue(struct ng_queue *ngq, int *rw)
1813 {
1814 item_p item;
1815 u_int add_arg;
1816
1817 mtx_assert(&ngq->q_mtx, MA_OWNED);
1818 /*
1819 * If there is nothing queued, then just return.
1820 * No point in continuing.
1821 * XXXGL: assert this?
1822 */
1823 if (!QUEUE_ACTIVE(ngq)) {
1824 CTR4(KTR_NET, "%20s: node [%x] (%p) queue empty; "
1825 "queue flags 0x%lx", __func__,
1826 ngq->q_node->nd_ID, ngq->q_node, ngq->q_flags);
1827 return (NULL);
1828 }
1829
1830 /*
1831 * From here, we can assume there is a head item.
1832 * We need to find out what it is and if it can be dequeued, given
1833 * the current state of the node.
1834 */
1835 if (HEAD_IS_READER(ngq)) {
1836 if (!QUEUED_READER_CAN_PROCEED(ngq)) {
1837 /*
1838 * It's a reader but we can't use it.
1839 * We are stalled so make sure we don't
1840 * get called again until something changes.
1841 */
1842 ng_worklist_remove(ngq->q_node);
1843 CTR4(KTR_NET, "%20s: node [%x] (%p) queued reader "
1844 "can't proceed; queue flags 0x%lx", __func__,
1845 ngq->q_node->nd_ID, ngq->q_node, ngq->q_flags);
1846 return (NULL);
1847 }
1848 /*
1849 * Head of queue is a reader and we have no write active.
1850 * We don't care how many readers are already active.
1851 * Add the correct increment for the reader count.
1852 */
1853 add_arg = READER_INCREMENT;
1854 *rw = NGQRW_R;
1855 } else if (QUEUED_WRITER_CAN_PROCEED(ngq)) {
1856 /*
1857 * There is a pending write, no readers and no active writer.
1858 * This means we can go ahead with the pending writer. Note
1859 * the fact that we now have a writer, ready for when we take
1860 * it off the queue.
1861 *
1862 * We don't need to worry about a possible collision with the
1863 * fasttrack reader.
1864 *
1865 * The fasttrack thread may take a long time to discover that we
1866 * are running so we would have an inconsistent state in the
1867 * flags for a while. Since we ignore the reader count
1868 * entirely when the WRITER_ACTIVE flag is set, this should
1869 * not matter (in fact it is defined that way). If it tests
1870 * the flag before this operation, the OP_PENDING flag
1871 * will make it fail, and if it tests it later, the
1872 * WRITER_ACTIVE flag will do the same. If it is SO slow that
1873 * we have actually completed the operation, and neither flag
1874 * is set by the time that it tests the flags, then it is
1875 * actually ok for it to continue. If it completes and we've
1876 * finished and the read pending is set it still fails.
1877 *
1878 * So we can just ignore it, as long as we can ensure that the
1879 * transition from WRITE_PENDING state to the WRITER_ACTIVE
1880 * state is atomic.
1881 *
1882 * After failing, first it will be held back by the mutex, then
1883 * when it can proceed, it will queue its request, then it
1884 * would arrive at this function. Usually it will have to
1885 * leave empty handed because the ACTIVE WRITER bit will be
1886 * set.
1887 *
1888 * Adjust the flags for the new active writer.
1889 */
1890 add_arg = WRITER_ACTIVE;
1891 *rw = NGQRW_W;
1892 /*
1893 * We want to write "active writer, no readers " Now go make
1894 * it true. In fact there may be a number in the readers
1895 * count but we know it is not true and will be fixed soon.
1896 * We will fix the flags for the next pending entry in a
1897 * moment.
1898 */
1899 } else {
1900 /*
1901 * We can't dequeue anything.. return and say so. Probably we
1902 * have a write pending and the readers count is non zero. If
1903 * we got here because a reader hit us just at the wrong
1904 * moment with the fasttrack code, and put us in a strange
1905 * state, then it will be coming through in just a moment,
1906 * (just as soon as we release the mutex) and keep things
1907 * moving.
1908 * Make sure we remove ourselves from the work queue. It
1909 * would be a waste of effort to do all this again.
1910 */
1911 ng_worklist_remove(ngq->q_node);
1912 CTR4(KTR_NET, "%20s: node [%x] (%p) can't dequeue anything; "
1913 "queue flags 0x%lx", __func__,
1914 ngq->q_node->nd_ID, ngq->q_node, ngq->q_flags);
1915 return (NULL);
1916 }
1917
1918 /*
1919 * Now we dequeue the request (whatever it may be) and correct the
1920 * pending flags and the next and last pointers.
1921 */
1922 item = ngq->queue;
1923 ngq->queue = item->el_next;
1924 CTR6(KTR_NET, "%20s: node [%x] (%p) dequeued item %p with flags 0x%lx; "
1925 "queue flags 0x%lx", __func__,
1926 ngq->q_node->nd_ID,ngq->q_node, item, item->el_flags, ngq->q_flags);
1927 if (ngq->last == &(item->el_next)) {
1928 /*
1929 * that was the last entry in the queue so set the 'last
1930 * pointer up correctly and make sure the pending flag is
1931 * clear.
1932 */
1933 add_arg += -OP_PENDING;
1934 ngq->last = &(ngq->queue);
1935 /*
1936 * Whatever flag was set will be cleared and
1937 * the new acive field will be set by the add as well,
1938 * so we don't need to change add_arg.
1939 * But we know we don't need to be on the work list.
1940 */
1941 atomic_add_long(&ngq->q_flags, add_arg);
1942 ng_worklist_remove(ngq->q_node);
1943 } else {
1944 /*
1945 * Since there is still something on the queue
1946 * we don't need to change the PENDING flag.
1947 */
1948 atomic_add_long(&ngq->q_flags, add_arg);
1949 /*
1950 * If we see more doable work, make sure we are
1951 * on the work queue.
1952 */
1953 if (NEXT_QUEUED_ITEM_CAN_PROCEED(ngq)) {
1954 ng_setisr(ngq->q_node);
1955 }
1956 }
1957 CTR6(KTR_NET, "%20s: node [%x] (%p) returning item %p as %s; "
1958 "queue flags 0x%lx", __func__,
1959 ngq->q_node->nd_ID, ngq->q_node, item, *rw ? "WRITER" : "READER" ,
1960 ngq->q_flags);
1961 return (item);
1962 }
1963
1964 /*
1965 * Queue a packet to be picked up by someone else.
1966 * We really don't care who, but we can't or don't want to hang around
1967 * to process it ourselves. We are probably an interrupt routine..
1968 * If the queue could be run, flag the netisr handler to start.
1969 */
1970 static __inline void
1971 ng_queue_rw(struct ng_queue * ngq, item_p item, int rw)
1972 {
1973 mtx_assert(&ngq->q_mtx, MA_OWNED);
1974
1975 if (rw == NGQRW_W)
1976 NGI_SET_WRITER(item);
1977 else
1978 NGI_SET_READER(item);
1979 item->el_next = NULL; /* maybe not needed */
1980 *ngq->last = item;
1981 CTR5(KTR_NET, "%20s: node [%x] (%p) queued item %p as %s", __func__,
1982 ngq->q_node->nd_ID, ngq->q_node, item, rw ? "WRITER" : "READER" );
1983 /*
1984 * If it was the first item in the queue then we need to
1985 * set the last pointer and the type flags.
1986 */
1987 if (ngq->last == &(ngq->queue)) {
1988 atomic_add_long(&ngq->q_flags, OP_PENDING);
1989 CTR3(KTR_NET, "%20s: node [%x] (%p) set OP_PENDING", __func__,
1990 ngq->q_node->nd_ID, ngq->q_node);
1991 }
1992
1993 ngq->last = &(item->el_next);
1994 /*
1995 * We can take the worklist lock with the node locked
1996 * BUT NOT THE REVERSE!
1997 */
1998 if (NEXT_QUEUED_ITEM_CAN_PROCEED(ngq))
1999 ng_setisr(ngq->q_node);
2000 }
2001
2002
2003 /*
2004 * This function 'cheats' in that it first tries to 'grab' the use of the
2005 * node, without going through the mutex. We can do this becasue of the
2006 * semantics of the lock. The semantics include a clause that says that the
2007 * value of the readers count is invalid if the WRITER_ACTIVE flag is set. It
2008 * also says that the WRITER_ACTIVE flag cannot be set if the readers count
2009 * is not zero. Note that this talks about what is valid to SET the
2010 * WRITER_ACTIVE flag, because from the moment it is set, the value if the
2011 * reader count is immaterial, and not valid. The two 'pending' flags have a
2012 * similar effect, in that If they are orthogonal to the two active fields in
2013 * how they are set, but if either is set, the attempted 'grab' need to be
2014 * backed out because there is earlier work, and we maintain ordering in the
2015 * queue. The result of this is that the reader request can try obtain use of
2016 * the node with only a single atomic addition, and without any of the mutex
2017 * overhead. If this fails the operation degenerates to the same as for other
2018 * cases.
2019 *
2020 */
2021 static __inline item_p
2022 ng_acquire_read(struct ng_queue *ngq, item_p item)
2023 {
2024 KASSERT(ngq != &ng_deadnode.nd_input_queue,
2025 ("%s: working on deadnode", __func__));
2026
2027 /* ######### Hack alert ######### */
2028 atomic_add_long(&ngq->q_flags, READER_INCREMENT);
2029 if ((ngq->q_flags & NGQ_RMASK) == 0) {
2030 /* Successfully grabbed node */
2031 CTR4(KTR_NET, "%20s: node [%x] (%p) fast acquired item %p",
2032 __func__, ngq->q_node->nd_ID, ngq->q_node, item);
2033 return (item);
2034 }
2035 /* undo the damage if we didn't succeed */
2036 atomic_subtract_long(&ngq->q_flags, READER_INCREMENT);
2037
2038 /* ######### End Hack alert ######### */
2039 mtx_lock_spin((&ngq->q_mtx));
2040 /*
2041 * Try again. Another processor (or interrupt for that matter) may
2042 * have removed the last queued item that was stopping us from
2043 * running, between the previous test, and the moment that we took
2044 * the mutex. (Or maybe a writer completed.)
2045 * Even if another fast-track reader hits during this period
2046 * we don't care as multiple readers is OK.
2047 */
2048 if ((ngq->q_flags & NGQ_RMASK) == 0) {
2049 atomic_add_long(&ngq->q_flags, READER_INCREMENT);
2050 mtx_unlock_spin((&ngq->q_mtx));
2051 CTR4(KTR_NET, "%20s: node [%x] (%p) slow acquired item %p",
2052 __func__, ngq->q_node->nd_ID, ngq->q_node, item);
2053 return (item);
2054 }
2055
2056 /*
2057 * and queue the request for later.
2058 */
2059 ng_queue_rw(ngq, item, NGQRW_R);
2060 mtx_unlock_spin(&(ngq->q_mtx));
2061
2062 return (NULL);
2063 }
2064
2065 static __inline item_p
2066 ng_acquire_write(struct ng_queue *ngq, item_p item)
2067 {
2068 KASSERT(ngq != &ng_deadnode.nd_input_queue,
2069 ("%s: working on deadnode", __func__));
2070
2071 restart:
2072 mtx_lock_spin(&(ngq->q_mtx));
2073 /*
2074 * If there are no readers, no writer, and no pending packets, then
2075 * we can just go ahead. In all other situations we need to queue the
2076 * request
2077 */
2078 if ((ngq->q_flags & NGQ_WMASK) == 0) {
2079 /* collision could happen *HERE* */
2080 atomic_add_long(&ngq->q_flags, WRITER_ACTIVE);
2081 mtx_unlock_spin((&ngq->q_mtx));
2082 if (ngq->q_flags & READER_MASK) {
2083 /* Collision with fast-track reader */
2084 atomic_subtract_long(&ngq->q_flags, WRITER_ACTIVE);
2085 goto restart;
2086 }
2087 CTR4(KTR_NET, "%20s: node [%x] (%p) acquired item %p",
2088 __func__, ngq->q_node->nd_ID, ngq->q_node, item);
2089 return (item);
2090 }
2091
2092 /*
2093 * and queue the request for later.
2094 */
2095 ng_queue_rw(ngq, item, NGQRW_W);
2096 mtx_unlock_spin(&(ngq->q_mtx));
2097
2098 return (NULL);
2099 }
2100
2101 static __inline void
2102 ng_leave_read(struct ng_queue *ngq)
2103 {
2104 atomic_subtract_long(&ngq->q_flags, READER_INCREMENT);
2105 }
2106
2107 static __inline void
2108 ng_leave_write(struct ng_queue *ngq)
2109 {
2110 atomic_subtract_long(&ngq->q_flags, WRITER_ACTIVE);
2111 }
2112
2113 static void
2114 ng_flush_input_queue(struct ng_queue * ngq)
2115 {
2116 item_p item;
2117
2118 mtx_lock_spin(&ngq->q_mtx);
2119 while (ngq->queue) {
2120 item = ngq->queue;
2121 ngq->queue = item->el_next;
2122 if (ngq->last == &(item->el_next)) {
2123 ngq->last = &(ngq->queue);
2124 atomic_add_long(&ngq->q_flags, -OP_PENDING);
2125 }
2126 mtx_unlock_spin(&ngq->q_mtx);
2127 /* If the item is supplying a callback, call it with an error */
2128 if (item->apply != NULL) {
2129 (item->apply)(item->context, ENOENT);
2130 item->apply = NULL;
2131 }
2132 NG_FREE_ITEM(item);
2133 mtx_lock_spin(&ngq->q_mtx);
2134 }
2135 /*
2136 * Take us off the work queue if we are there.
2137 * We definatly have no work to be done.
2138 */
2139 ng_worklist_remove(ngq->q_node);
2140 mtx_unlock_spin(&ngq->q_mtx);
2141 }
2142
2143 /***********************************************************************
2144 * Externally visible method for sending or queueing messages or data.
2145 ***********************************************************************/
2146
2147 /*
2148 * The module code should have filled out the item correctly by this stage:
2149 * Common:
2150 * reference to destination node.
2151 * Reference to destination rcv hook if relevant.
2152 * Data:
2153 * pointer to mbuf
2154 * Control_Message:
2155 * pointer to msg.
2156 * ID of original sender node. (return address)
2157 * Function:
2158 * Function pointer
2159 * void * argument
2160 * integer argument
2161 *
2162 * The nodes have several routines and macros to help with this task:
2163 */
2164
2165 int
2166 ng_snd_item(item_p item, int flags)
2167 {
2168 hook_p hook = NGI_HOOK(item);
2169 node_p node = NGI_NODE(item);
2170 int queue, rw;
2171 struct ng_queue * ngq = &node->nd_input_queue;
2172 int error = 0;
2173
2174 #ifdef NETGRAPH_DEBUG
2175 _ngi_check(item, __FILE__, __LINE__);
2176 #endif
2177
2178 queue = (flags & NG_QUEUE) ? 1 : 0;
2179
2180 if (item == NULL) {
2181 TRAP_ERROR();
2182 return (EINVAL); /* failed to get queue element */
2183 }
2184 if (node == NULL) {
2185 NG_FREE_ITEM(item);
2186 TRAP_ERROR();
2187 return (EINVAL); /* No address */
2188 }
2189 switch(item->el_flags & NGQF_TYPE) {
2190 case NGQF_DATA:
2191 /*
2192 * DATA MESSAGE
2193 * Delivered to a node via a non-optional hook.
2194 * Both should be present in the item even though
2195 * the node is derivable from the hook.
2196 * References are held on both by the item.
2197 */
2198
2199 /* Protect nodes from sending NULL pointers
2200 * to each other
2201 */
2202 if (NGI_M(item) == NULL)
2203 return (EINVAL);
2204
2205 CHECK_DATA_MBUF(NGI_M(item));
2206 if (hook == NULL) {
2207 NG_FREE_ITEM(item);
2208 TRAP_ERROR();
2209 return(EINVAL);
2210 }
2211 if ((NG_HOOK_NOT_VALID(hook))
2212 || (NG_NODE_NOT_VALID(NG_HOOK_NODE(hook)))) {
2213 NG_FREE_ITEM(item);
2214 return (ENOTCONN);
2215 }
2216 if ((hook->hk_flags & HK_QUEUE)) {
2217 queue = 1;
2218 }
2219 break;
2220 case NGQF_MESG:
2221 /*
2222 * CONTROL MESSAGE
2223 * Delivered to a node.
2224 * Hook is optional.
2225 * References are held by the item on the node and
2226 * the hook if it is present.
2227 */
2228 if (hook && (hook->hk_flags & HK_QUEUE)) {
2229 queue = 1;
2230 }
2231 break;
2232 case NGQF_FN:
2233 break;
2234 default:
2235 NG_FREE_ITEM(item);
2236 TRAP_ERROR();
2237 return (EINVAL);
2238 }
2239 switch(item->el_flags & NGQF_RW) {
2240 case NGQF_READER:
2241 rw = NGQRW_R;
2242 break;
2243 case NGQF_WRITER:
2244 rw = NGQRW_W;
2245 break;
2246 default:
2247 panic("%s: invalid item flags %lx", __func__, item->el_flags);
2248 }
2249
2250 /*
2251 * If the node specifies single threading, force writer semantics.
2252 * Similarly, the node may say one hook always produces writers.
2253 * These are overrides.
2254 */
2255 if ((node->nd_flags & NGF_FORCE_WRITER)
2256 || (hook && (hook->hk_flags & HK_FORCE_WRITER)))
2257 rw = NGQRW_W;
2258
2259 if (queue) {
2260 /* Put it on the queue for that node*/
2261 #ifdef NETGRAPH_DEBUG
2262 _ngi_check(item, __FILE__, __LINE__);
2263 #endif
2264 mtx_lock_spin(&(ngq->q_mtx));
2265 ng_queue_rw(ngq, item, rw);
2266 mtx_unlock_spin(&(ngq->q_mtx));
2267
2268 if (flags & NG_PROGRESS)
2269 return (EINPROGRESS);
2270 else
2271 return (0);
2272 }
2273
2274 /*
2275 * We already decided how we will be queueud or treated.
2276 * Try get the appropriate operating permission.
2277 */
2278 if (rw == NGQRW_R)
2279 item = ng_acquire_read(ngq, item);
2280 else
2281 item = ng_acquire_write(ngq, item);
2282
2283
2284 if (item == NULL) {
2285 if (flags & NG_PROGRESS)
2286 return (EINPROGRESS);
2287 else
2288 return (0);
2289 }
2290
2291 #ifdef NETGRAPH_DEBUG
2292 _ngi_check(item, __FILE__, __LINE__);
2293 #endif
2294
2295 NGI_GET_NODE(item, node); /* zaps stored node */
2296
2297 error = ng_apply_item(node, item, rw); /* drops r/w lock when done */
2298
2299 /*
2300 * If the node goes away when we remove the reference,
2301 * whatever we just did caused it.. whatever we do, DO NOT
2302 * access the node again!
2303 */
2304 if (NG_NODE_UNREF(node) == 0) {
2305 return (error);
2306 }
2307
2308 mtx_lock_spin(&(ngq->q_mtx));
2309 if (NEXT_QUEUED_ITEM_CAN_PROCEED(ngq))
2310 ng_setisr(ngq->q_node);
2311 mtx_unlock_spin(&(ngq->q_mtx));
2312
2313 return (error);
2314 }
2315
2316 /*
2317 * We have an item that was possibly queued somewhere.
2318 * It should contain all the information needed
2319 * to run it on the appropriate node/hook.
2320 */
2321 static int
2322 ng_apply_item(node_p node, item_p item, int rw)
2323 {
2324 hook_p hook;
2325 int error = 0;
2326 ng_rcvdata_t *rcvdata;
2327 ng_rcvmsg_t *rcvmsg;
2328 ng_apply_t *apply = NULL;
2329 void *context = NULL;
2330
2331 NGI_GET_HOOK(item, hook); /* clears stored hook */
2332 #ifdef NETGRAPH_DEBUG
2333 _ngi_check(item, __FILE__, __LINE__);
2334 #endif
2335
2336 /*
2337 * If the item has an "apply" callback, store it.
2338 * Clear item's callback immediately, to avoid an extra call if
2339 * the item is reused by the destination node.
2340 */
2341 if (item->apply != NULL) {
2342 apply = item->apply;
2343 context = item->context;
2344 item->apply = NULL;
2345 }
2346
2347 switch (item->el_flags & NGQF_TYPE) {
2348 case NGQF_DATA:
2349 /*
2350 * Check things are still ok as when we were queued.
2351 */
2352 if ((hook == NULL)
2353 || NG_HOOK_NOT_VALID(hook)
2354 || NG_NODE_NOT_VALID(node) ) {
2355 error = EIO;
2356 NG_FREE_ITEM(item);
2357 break;
2358 }
2359 /*
2360 * If no receive method, just silently drop it.
2361 * Give preference to the hook over-ride method
2362 */
2363 if ((!(rcvdata = hook->hk_rcvdata))
2364 && (!(rcvdata = NG_HOOK_NODE(hook)->nd_type->rcvdata))) {
2365 error = 0;
2366 NG_FREE_ITEM(item);
2367 break;
2368 }
2369 error = (*rcvdata)(hook, item);
2370 break;
2371 case NGQF_MESG:
2372 if (hook) {
2373 if (NG_HOOK_NOT_VALID(hook)) {
2374 /*
2375 * The hook has been zapped then we can't
2376 * use it. Immediatly drop its reference.
2377 * The message may not need it.
2378 */
2379 NG_HOOK_UNREF(hook);
2380 hook = NULL;
2381 }
2382 }
2383 /*
2384 * Similarly, if the node is a zombie there is
2385 * nothing we can do with it, drop everything.
2386 */
2387 if (NG_NODE_NOT_VALID(node)) {
2388 TRAP_ERROR();
2389 error = EINVAL;
2390 NG_FREE_ITEM(item);
2391 } else {
2392 /*
2393 * Call the appropriate message handler for the object.
2394 * It is up to the message handler to free the message.
2395 * If it's a generic message, handle it generically,
2396 * otherwise call the type's message handler
2397 * (if it exists)
2398 * XXX (race). Remember that a queued message may
2399 * reference a node or hook that has just been
2400 * invalidated. It will exist as the queue code
2401 * is holding a reference, but..
2402 */
2403
2404 struct ng_mesg *msg = NGI_MSG(item);
2405
2406 /*
2407 * check if the generic handler owns it.
2408 */
2409 if ((msg->header.typecookie == NGM_GENERIC_COOKIE)
2410 && ((msg->header.flags & NGF_RESP) == 0)) {
2411 error = ng_generic_msg(node, item, hook);
2412 break;
2413 }
2414 /*
2415 * Now see if there is a handler (hook or node specific)
2416 * in the target node. If none, silently discard.
2417 */
2418 if (((!hook) || (!(rcvmsg = hook->hk_rcvmsg)))
2419 && (!(rcvmsg = node->nd_type->rcvmsg))) {
2420 TRAP_ERROR();
2421 error = 0;
2422 NG_FREE_ITEM(item);
2423 break;
2424 }
2425 error = (*rcvmsg)(node, item, hook);
2426 }
2427 break;
2428 case NGQF_FN:
2429 /*
2430 * We have to implicitly trust the hook,
2431 * as some of these are used for system purposes
2432 * where the hook is invalid. In the case of
2433 * the shutdown message we allow it to hit
2434 * even if the node is invalid.
2435 */
2436 if ((NG_NODE_NOT_VALID(node))
2437 && (NGI_FN(item) != &ng_rmnode)) {
2438 TRAP_ERROR();
2439 error = EINVAL;
2440 NG_FREE_ITEM(item);
2441 break;
2442 }
2443 (*NGI_FN(item))(node, hook, NGI_ARG1(item), NGI_ARG2(item));
2444 NG_FREE_ITEM(item);
2445 break;
2446
2447 }
2448 /*
2449 * We held references on some of the resources
2450 * that we took from the item. Now that we have
2451 * finished doing everything, drop those references.
2452 */
2453 if (hook) {
2454 NG_HOOK_UNREF(hook);
2455 }
2456
2457 if (rw == NGQRW_R) {
2458 ng_leave_read(&node->nd_input_queue);
2459 } else {
2460 ng_leave_write(&node->nd_input_queue);
2461 }
2462
2463 /* Apply callback. */
2464 if (apply != NULL)
2465 (*apply)(context, error);
2466
2467 return (error);
2468 }
2469
2470 /***********************************************************************
2471 * Implement the 'generic' control messages
2472 ***********************************************************************/
2473 static int
2474 ng_generic_msg(node_p here, item_p item, hook_p lasthook)
2475 {
2476 int error = 0;
2477 struct ng_mesg *msg;
2478 struct ng_mesg *resp = NULL;
2479
2480 NGI_GET_MSG(item, msg);
2481 if (msg->header.typecookie != NGM_GENERIC_COOKIE) {
2482 TRAP_ERROR();
2483 error = EINVAL;
2484 goto out;
2485 }
2486 switch (msg->header.cmd) {
2487 case NGM_SHUTDOWN:
2488 ng_rmnode(here, NULL, NULL, 0);
2489 break;
2490 case NGM_MKPEER:
2491 {
2492 struct ngm_mkpeer *const mkp = (struct ngm_mkpeer *) msg->data;
2493
2494 if (msg->header.arglen != sizeof(*mkp)) {
2495 TRAP_ERROR();
2496 error = EINVAL;
2497 break;
2498 }
2499 mkp->type[sizeof(mkp->type) - 1] = '\0';
2500 mkp->ourhook[sizeof(mkp->ourhook) - 1] = '\0';
2501 mkp->peerhook[sizeof(mkp->peerhook) - 1] = '\0';
2502 error = ng_mkpeer(here, mkp->ourhook, mkp->peerhook, mkp->type);
2503 break;
2504 }
2505 case NGM_CONNECT:
2506 {
2507 struct ngm_connect *const con =
2508 (struct ngm_connect *) msg->data;
2509 node_p node2;
2510
2511 if (msg->header.arglen != sizeof(*con)) {
2512 TRAP_ERROR();
2513 error = EINVAL;
2514 break;
2515 }
2516 con->path[sizeof(con->path) - 1] = '\0';
2517 con->ourhook[sizeof(con->ourhook) - 1] = '\0';
2518 con->peerhook[sizeof(con->peerhook) - 1] = '\0';
2519 /* Don't forget we get a reference.. */
2520 error = ng_path2noderef(here, con->path, &node2, NULL);
2521 if (error)
2522 break;
2523 error = ng_con_nodes(here, con->ourhook, node2, con->peerhook);
2524 NG_NODE_UNREF(node2);
2525 break;
2526 }
2527 case NGM_NAME:
2528 {
2529 struct ngm_name *const nam = (struct ngm_name *) msg->data;
2530
2531 if (msg->header.arglen != sizeof(*nam)) {
2532 TRAP_ERROR();
2533 error = EINVAL;
2534 break;
2535 }
2536 nam->name[sizeof(nam->name) - 1] = '\0';
2537 error = ng_name_node(here, nam->name);
2538 break;
2539 }
2540 case NGM_RMHOOK:
2541 {
2542 struct ngm_rmhook *const rmh = (struct ngm_rmhook *) msg->data;
2543 hook_p hook;
2544
2545 if (msg->header.arglen != sizeof(*rmh)) {
2546 TRAP_ERROR();
2547 error = EINVAL;
2548 break;
2549 }
2550 rmh->ourhook[sizeof(rmh->ourhook) - 1] = '\0';
2551 if ((hook = ng_findhook(here, rmh->ourhook)) != NULL)
2552 ng_destroy_hook(hook);
2553 break;
2554 }
2555 case NGM_NODEINFO:
2556 {
2557 struct nodeinfo *ni;
2558
2559 NG_MKRESPONSE(resp, msg, sizeof(*ni), M_NOWAIT);
2560 if (resp == NULL) {
2561 error = ENOMEM;
2562 break;
2563 }
2564
2565 /* Fill in node info */
2566 ni = (struct nodeinfo *) resp->data;
2567 if (NG_NODE_HAS_NAME(here))
2568 strcpy(ni->name, NG_NODE_NAME(here));
2569 strcpy(ni->type, here->nd_type->name);
2570 ni->id = ng_node2ID(here);
2571 ni->hooks = here->nd_numhooks;
2572 break;
2573 }
2574 case NGM_LISTHOOKS:
2575 {
2576 const int nhooks = here->nd_numhooks;
2577 struct hooklist *hl;
2578 struct nodeinfo *ni;
2579 hook_p hook;
2580
2581 /* Get response struct */
2582 NG_MKRESPONSE(resp, msg, sizeof(*hl)
2583 + (nhooks * sizeof(struct linkinfo)), M_NOWAIT);
2584 if (resp == NULL) {
2585 error = ENOMEM;
2586 break;
2587 }
2588 hl = (struct hooklist *) resp->data;
2589 ni = &hl->nodeinfo;
2590
2591 /* Fill in node info */
2592 if (NG_NODE_HAS_NAME(here))
2593 strcpy(ni->name, NG_NODE_NAME(here));
2594 strcpy(ni->type, here->nd_type->name);
2595 ni->id = ng_node2ID(here);
2596
2597 /* Cycle through the linked list of hooks */
2598 ni->hooks = 0;
2599 LIST_FOREACH(hook, &here->nd_hooks, hk_hooks) {
2600 struct linkinfo *const link = &hl->link[ni->hooks];
2601
2602 if (ni->hooks >= nhooks) {
2603 log(LOG_ERR, "%s: number of %s changed\n",
2604 __func__, "hooks");
2605 break;
2606 }
2607 if (NG_HOOK_NOT_VALID(hook))
2608 continue;
2609 strcpy(link->ourhook, NG_HOOK_NAME(hook));
2610 strcpy(link->peerhook, NG_PEER_HOOK_NAME(hook));
2611 if (NG_PEER_NODE_NAME(hook)[0] != '\0')
2612 strcpy(link->nodeinfo.name,
2613 NG_PEER_NODE_NAME(hook));
2614 strcpy(link->nodeinfo.type,
2615 NG_PEER_NODE(hook)->nd_type->name);
2616 link->nodeinfo.id = ng_node2ID(NG_PEER_NODE(hook));
2617 link->nodeinfo.hooks = NG_PEER_NODE(hook)->nd_numhooks;
2618 ni->hooks++;
2619 }
2620 break;
2621 }
2622
2623 case NGM_LISTNAMES:
2624 case NGM_LISTNODES:
2625 {
2626 const int unnamed = (msg->header.cmd == NGM_LISTNODES);
2627 struct namelist *nl;
2628 node_p node;
2629 int num = 0;
2630
2631 mtx_lock(&ng_nodelist_mtx);
2632 /* Count number of nodes */
2633 LIST_FOREACH(node, &ng_nodelist, nd_nodes) {
2634 if (NG_NODE_IS_VALID(node)
2635 && (unnamed || NG_NODE_HAS_NAME(node))) {
2636 num++;
2637 }
2638 }
2639 mtx_unlock(&ng_nodelist_mtx);
2640
2641 /* Get response struct */
2642 NG_MKRESPONSE(resp, msg, sizeof(*nl)
2643 + (num * sizeof(struct nodeinfo)), M_NOWAIT);
2644 if (resp == NULL) {
2645 error = ENOMEM;
2646 break;
2647 }
2648 nl = (struct namelist *) resp->data;
2649
2650 /* Cycle through the linked list of nodes */
2651 nl->numnames = 0;
2652 mtx_lock(&ng_nodelist_mtx);
2653 LIST_FOREACH(node, &ng_nodelist, nd_nodes) {
2654 struct nodeinfo *const np = &nl->nodeinfo[nl->numnames];
2655
2656 if (nl->numnames >= num) {
2657 log(LOG_ERR, "%s: number of %s changed\n",
2658 __func__, "nodes");
2659 break;
2660 }
2661 if (NG_NODE_NOT_VALID(node))
2662 continue;
2663 if (!unnamed && (! NG_NODE_HAS_NAME(node)))
2664 continue;
2665 if (NG_NODE_HAS_NAME(node))
2666 strcpy(np->name, NG_NODE_NAME(node));
2667 strcpy(np->type, node->nd_type->name);
2668 np->id = ng_node2ID(node);
2669 np->hooks = node->nd_numhooks;
2670 nl->numnames++;
2671 }
2672 mtx_unlock(&ng_nodelist_mtx);
2673 break;
2674 }
2675
2676 case NGM_LISTTYPES:
2677 {
2678 struct typelist *tl;
2679 struct ng_type *type;
2680 int num = 0;
2681
2682 mtx_lock(&ng_typelist_mtx);
2683 /* Count number of types */
2684 LIST_FOREACH(type, &ng_typelist, types) {
2685 num++;
2686 }
2687 mtx_unlock(&ng_typelist_mtx);
2688
2689 /* Get response struct */
2690 NG_MKRESPONSE(resp, msg, sizeof(*tl)
2691 + (num * sizeof(struct typeinfo)), M_NOWAIT);
2692 if (resp == NULL) {
2693 error = ENOMEM;
2694 break;
2695 }
2696 tl = (struct typelist *) resp->data;
2697
2698 /* Cycle through the linked list of types */
2699 tl->numtypes = 0;
2700 mtx_lock(&ng_typelist_mtx);
2701 LIST_FOREACH(type, &ng_typelist, types) {
2702 struct typeinfo *const tp = &tl->typeinfo[tl->numtypes];
2703
2704 if (tl->numtypes >= num) {
2705 log(LOG_ERR, "%s: number of %s changed\n",
2706 __func__, "types");
2707 break;
2708 }
2709 strcpy(tp->type_name, type->name);
2710 tp->numnodes = type->refs - 1; /* don't count list */
2711 tl->numtypes++;
2712 }
2713 mtx_unlock(&ng_typelist_mtx);
2714 break;
2715 }
2716
2717 case NGM_BINARY2ASCII:
2718 {
2719 int bufSize = 20 * 1024; /* XXX hard coded constant */
2720 const struct ng_parse_type *argstype;
2721 const struct ng_cmdlist *c;
2722 struct ng_mesg *binary, *ascii;
2723
2724 /* Data area must contain a valid netgraph message */
2725 binary = (struct ng_mesg *)msg->data;
2726 if (msg->header.arglen < sizeof(struct ng_mesg) ||
2727 (msg->header.arglen - sizeof(struct ng_mesg) <
2728 binary->header.arglen)) {
2729 TRAP_ERROR();
2730 error = EINVAL;
2731 break;
2732 }
2733
2734 /* Get a response message with lots of room */
2735 NG_MKRESPONSE(resp, msg, sizeof(*ascii) + bufSize, M_NOWAIT);
2736 if (resp == NULL) {
2737 error = ENOMEM;
2738 break;
2739 }
2740 ascii = (struct ng_mesg *)resp->data;
2741
2742 /* Copy binary message header to response message payload */
2743 bcopy(binary, ascii, sizeof(*binary));
2744
2745 /* Find command by matching typecookie and command number */
2746 for (c = here->nd_type->cmdlist;
2747 c != NULL && c->name != NULL; c++) {
2748 if (binary->header.typecookie == c->cookie
2749 && binary->header.cmd == c->cmd)
2750 break;
2751 }
2752 if (c == NULL || c->name == NULL) {
2753 for (c = ng_generic_cmds; c->name != NULL; c++) {
2754 if (binary->header.typecookie == c->cookie
2755 && binary->header.cmd == c->cmd)
2756 break;
2757 }
2758 if (c->name == NULL) {
2759 NG_FREE_MSG(resp);
2760 error = ENOSYS;
2761 break;
2762 }
2763 }
2764
2765 /* Convert command name to ASCII */
2766 snprintf(ascii->header.cmdstr, sizeof(ascii->header.cmdstr),
2767 "%s", c->name);
2768
2769 /* Convert command arguments to ASCII */
2770 argstype = (binary->header.flags & NGF_RESP) ?
2771 c->respType : c->mesgType;
2772 if (argstype == NULL) {
2773 *ascii->data = '\0';
2774 } else {
2775 if ((error = ng_unparse(argstype,
2776 (u_char *)binary->data,
2777 ascii->data, bufSize)) != 0) {
2778 NG_FREE_MSG(resp);
2779 break;
2780 }
2781 }
2782
2783 /* Return the result as struct ng_mesg plus ASCII string */
2784 bufSize = strlen(ascii->data) + 1;
2785 ascii->header.arglen = bufSize;
2786 resp->header.arglen = sizeof(*ascii) + bufSize;
2787 break;
2788 }
2789
2790 case NGM_ASCII2BINARY:
2791 {
2792 int bufSize = 2000; /* XXX hard coded constant */
2793 const struct ng_cmdlist *c;
2794 const struct ng_parse_type *argstype;
2795 struct ng_mesg *ascii, *binary;
2796 int off = 0;
2797
2798 /* Data area must contain at least a struct ng_mesg + '\0' */
2799 ascii = (struct ng_mesg *)msg->data;
2800 if ((msg->header.arglen < sizeof(*ascii) + 1) ||
2801 (ascii->header.arglen < 1) ||
2802 (msg->header.arglen < sizeof(*ascii) +
2803 ascii->header.arglen)) {
2804 TRAP_ERROR();
2805 error = EINVAL;
2806 break;
2807 }
2808 ascii->data[ascii->header.arglen - 1] = '\0';
2809
2810 /* Get a response message with lots of room */
2811 NG_MKRESPONSE(resp, msg, sizeof(*binary) + bufSize, M_NOWAIT);
2812 if (resp == NULL) {
2813 error = ENOMEM;
2814 break;
2815 }
2816 binary = (struct ng_mesg *)resp->data;
2817
2818 /* Copy ASCII message header to response message payload */
2819 bcopy(ascii, binary, sizeof(*ascii));
2820
2821 /* Find command by matching ASCII command string */
2822 for (c = here->nd_type->cmdlist;
2823 c != NULL && c->name != NULL; c++) {
2824 if (strcmp(ascii->header.cmdstr, c->name) == 0)
2825 break;
2826 }
2827 if (c == NULL || c->name == NULL) {
2828 for (c = ng_generic_cmds; c->name != NULL; c++) {
2829 if (strcmp(ascii->header.cmdstr, c->name) == 0)
2830 break;
2831 }
2832 if (c->name == NULL) {
2833 NG_FREE_MSG(resp);
2834 error = ENOSYS;
2835 break;
2836 }
2837 }
2838
2839 /* Convert command name to binary */
2840 binary->header.cmd = c->cmd;
2841 binary->header.typecookie = c->cookie;
2842
2843 /* Convert command arguments to binary */
2844 argstype = (binary->header.flags & NGF_RESP) ?
2845 c->respType : c->mesgType;
2846 if (argstype == NULL) {
2847 bufSize = 0;
2848 } else {
2849 if ((error = ng_parse(argstype, ascii->data,
2850 &off, (u_char *)binary->data, &bufSize)) != 0) {
2851 NG_FREE_MSG(resp);
2852 break;
2853 }
2854 }
2855
2856 /* Return the result */
2857 binary->header.arglen = bufSize;
2858 resp->header.arglen = sizeof(*binary) + bufSize;
2859 break;
2860 }
2861
2862 case NGM_TEXT_CONFIG:
2863 case NGM_TEXT_STATUS:
2864 /*
2865 * This one is tricky as it passes the command down to the
2866 * actual node, even though it is a generic type command.
2867 * This means we must assume that the item/msg is already freed
2868 * when control passes back to us.
2869 */
2870 if (here->nd_type->rcvmsg != NULL) {
2871 NGI_MSG(item) = msg; /* put it back as we found it */
2872 return((*here->nd_type->rcvmsg)(here, item, lasthook));
2873 }
2874 /* Fall through if rcvmsg not supported */
2875 default:
2876 TRAP_ERROR();
2877 error = EINVAL;
2878 }
2879 /*
2880 * Sometimes a generic message may be statically allocated
2881 * to avoid problems with allocating when in tight memeory situations.
2882 * Don't free it if it is so.
2883 * I break them appart here, because erros may cause a free if the item
2884 * in which case we'd be doing it twice.
2885 * they are kept together above, to simplify freeing.
2886 */
2887 out:
2888 NG_RESPOND_MSG(error, here, item, resp);
2889 if (msg)
2890 NG_FREE_MSG(msg);
2891 return (error);
2892 }
2893
2894 /************************************************************************
2895 Queue element get/free routines
2896 ************************************************************************/
2897
2898 uma_zone_t ng_qzone;
2899 static int maxalloc = 512; /* limit the damage of a leak */
2900
2901 TUNABLE_INT("net.graph.maxalloc", &maxalloc);
2902 SYSCTL_INT(_net_graph, OID_AUTO, maxalloc, CTLFLAG_RDTUN, &maxalloc,
2903 0, "Maximum number of queue items to allocate");
2904
2905 #ifdef NETGRAPH_DEBUG
2906 static TAILQ_HEAD(, ng_item) ng_itemlist = TAILQ_HEAD_INITIALIZER(ng_itemlist);
2907 static int allocated; /* number of items malloc'd */
2908 #endif
2909
2910 /*
2911 * Get a queue entry.
2912 * This is usually called when a packet first enters netgraph.
2913 * By definition, this is usually from an interrupt, or from a user.
2914 * Users are not so important, but try be quick for the times that it's
2915 * an interrupt.
2916 */
2917 static __inline item_p
2918 ng_getqblk(int flags)
2919 {
2920 item_p item = NULL;
2921 int wait;
2922
2923 wait = (flags & NG_WAITOK) ? M_WAITOK : M_NOWAIT;
2924
2925 item = uma_zalloc(ng_qzone, wait | M_ZERO);
2926
2927 #ifdef NETGRAPH_DEBUG
2928 if (item) {
2929 mtx_lock(&ngq_mtx);
2930 TAILQ_INSERT_TAIL(&ng_itemlist, item, all);
2931 allocated++;
2932 mtx_unlock(&ngq_mtx);
2933 }
2934 #endif
2935
2936 return (item);
2937 }
2938
2939 /*
2940 * Release a queue entry
2941 */
2942 void
2943 ng_free_item(item_p item)
2944 {
2945 KASSERT(item->apply == NULL, ("%s: leaking apply callback", __func__));
2946
2947 /*
2948 * The item may hold resources on it's own. We need to free
2949 * these before we can free the item. What they are depends upon
2950 * what kind of item it is. it is important that nodes zero
2951 * out pointers to resources that they remove from the item
2952 * or we release them again here.
2953 */
2954 switch (item->el_flags & NGQF_TYPE) {
2955 case NGQF_DATA:
2956 /* If we have an mbuf still attached.. */
2957 NG_FREE_M(_NGI_M(item));
2958 break;
2959 case NGQF_MESG:
2960 _NGI_RETADDR(item) = 0;
2961 NG_FREE_MSG(_NGI_MSG(item));
2962 break;
2963 case NGQF_FN:
2964 /* nothing to free really, */
2965 _NGI_FN(item) = NULL;
2966 _NGI_ARG1(item) = NULL;
2967 _NGI_ARG2(item) = 0;
2968 case NGQF_UNDEF:
2969 break;
2970 }
2971 /* If we still have a node or hook referenced... */
2972 _NGI_CLR_NODE(item);
2973 _NGI_CLR_HOOK(item);
2974
2975 #ifdef NETGRAPH_DEBUG
2976 mtx_lock(&ngq_mtx);
2977 TAILQ_REMOVE(&ng_itemlist, item, all);
2978 allocated--;
2979 mtx_unlock(&ngq_mtx);
2980 #endif
2981 uma_zfree(ng_qzone, item);
2982 }
2983
2984 /************************************************************************
2985 Module routines
2986 ************************************************************************/
2987
2988 /*
2989 * Handle the loading/unloading of a netgraph node type module
2990 */
2991 int
2992 ng_mod_event(module_t mod, int event, void *data)
2993 {
2994 struct ng_type *const type = data;
2995 int s, error = 0;
2996
2997 switch (event) {
2998 case MOD_LOAD:
2999
3000 /* Register new netgraph node type */
3001 s = splnet();
3002 if ((error = ng_newtype(type)) != 0) {
3003 splx(s);
3004 break;
3005 }
3006
3007 /* Call type specific code */
3008 if (type->mod_event != NULL)
3009 if ((error = (*type->mod_event)(mod, event, data))) {
3010 mtx_lock(&ng_typelist_mtx);
3011 type->refs--; /* undo it */
3012 LIST_REMOVE(type, types);
3013 mtx_unlock(&ng_typelist_mtx);
3014 }
3015 splx(s);
3016 break;
3017
3018 case MOD_UNLOAD:
3019 s = splnet();
3020 if (type->refs > 1) { /* make sure no nodes exist! */
3021 error = EBUSY;
3022 } else {
3023 if (type->refs == 0) {
3024 /* failed load, nothing to undo */
3025 splx(s);
3026 break;
3027 }
3028 if (type->mod_event != NULL) { /* check with type */
3029 error = (*type->mod_event)(mod, event, data);
3030 if (error != 0) { /* type refuses.. */
3031 splx(s);
3032 break;
3033 }
3034 }
3035 mtx_lock(&ng_typelist_mtx);
3036 LIST_REMOVE(type, types);
3037 mtx_unlock(&ng_typelist_mtx);
3038 }
3039 splx(s);
3040 break;
3041
3042 default:
3043 if (type->mod_event != NULL)
3044 error = (*type->mod_event)(mod, event, data);
3045 else
3046 error = EOPNOTSUPP; /* XXX ? */
3047 break;
3048 }
3049 return (error);
3050 }
3051
3052 /*
3053 * Handle loading and unloading for this code.
3054 * The only thing we need to link into is the NETISR strucure.
3055 */
3056 static int
3057 ngb_mod_event(module_t mod, int event, void *data)
3058 {
3059 int error = 0;
3060
3061 switch (event) {
3062 case MOD_LOAD:
3063 /* Initialize everything. */
3064 mtx_init(&ng_worklist_mtx, "ng_worklist", NULL, MTX_SPIN);
3065 mtx_init(&ng_typelist_mtx, "netgraph types mutex", NULL,
3066 MTX_DEF);
3067 mtx_init(&ng_nodelist_mtx, "netgraph nodelist mutex", NULL,
3068 MTX_DEF);
3069 mtx_init(&ng_idhash_mtx, "netgraph idhash mutex", NULL,
3070 MTX_DEF);
3071 mtx_init(&ng_topo_mtx, "netgraph topology mutex", NULL,
3072 MTX_DEF);
3073 #ifdef NETGRAPH_DEBUG
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 netisr_register(NETISR_NETGRAPH, (netisr_t *)ngintr, NULL,
3081 NETISR_MPSAFE);
3082 break;
3083 case MOD_UNLOAD:
3084 /* You cant unload it because an interface may be using it. */
3085 error = EBUSY;
3086 break;
3087 default:
3088 error = EOPNOTSUPP;
3089 break;
3090 }
3091 return (error);
3092 }
3093
3094 static moduledata_t netgraph_mod = {
3095 "netgraph",
3096 ngb_mod_event,
3097 (NULL)
3098 };
3099 DECLARE_MODULE(netgraph, netgraph_mod, SI_SUB_NETGRAPH, SI_ORDER_MIDDLE);
3100 SYSCTL_NODE(_net, OID_AUTO, graph, CTLFLAG_RW, 0, "netgraph Family");
3101 SYSCTL_INT(_net_graph, OID_AUTO, abi_version, CTLFLAG_RD, 0, NG_ABI_VERSION,"");
3102 SYSCTL_INT(_net_graph, OID_AUTO, msg_version, CTLFLAG_RD, 0, NG_VERSION, "");
3103
3104 #ifdef NETGRAPH_DEBUG
3105 void
3106 dumphook (hook_p hook, char *file, int line)
3107 {
3108 printf("hook: name %s, %d refs, Last touched:\n",
3109 _NG_HOOK_NAME(hook), hook->hk_refs);
3110 printf(" Last active @ %s, line %d\n",
3111 hook->lastfile, hook->lastline);
3112 if (line) {
3113 printf(" problem discovered at file %s, line %d\n", file, line);
3114 }
3115 }
3116
3117 void
3118 dumpnode(node_p node, char *file, int line)
3119 {
3120 printf("node: ID [%x]: type '%s', %d hooks, flags 0x%x, %d refs, %s:\n",
3121 _NG_NODE_ID(node), node->nd_type->name,
3122 node->nd_numhooks, node->nd_flags,
3123 node->nd_refs, node->nd_name);
3124 printf(" Last active @ %s, line %d\n",
3125 node->lastfile, node->lastline);
3126 if (line) {
3127 printf(" problem discovered at file %s, line %d\n", file, line);
3128 }
3129 }
3130
3131 void
3132 dumpitem(item_p item, char *file, int line)
3133 {
3134 printf(" ACTIVE item, last used at %s, line %d",
3135 item->lastfile, item->lastline);
3136 switch(item->el_flags & NGQF_TYPE) {
3137 case NGQF_DATA:
3138 printf(" - [data]\n");
3139 break;
3140 case NGQF_MESG:
3141 printf(" - retaddr[%d]:\n", _NGI_RETADDR(item));
3142 break;
3143 case NGQF_FN:
3144 printf(" - fn@%p (%p, %p, %p, %d (%x))\n",
3145 item->body.fn.fn_fn,
3146 _NGI_NODE(item),
3147 _NGI_HOOK(item),
3148 item->body.fn.fn_arg1,
3149 item->body.fn.fn_arg2,
3150 item->body.fn.fn_arg2);
3151 break;
3152 case NGQF_UNDEF:
3153 printf(" - UNDEFINED!\n");
3154 }
3155 if (line) {
3156 printf(" problem discovered at file %s, line %d\n", file, line);
3157 if (_NGI_NODE(item)) {
3158 printf("node %p ([%x])\n",
3159 _NGI_NODE(item), ng_node2ID(_NGI_NODE(item)));
3160 }
3161 }
3162 }
3163
3164 static void
3165 ng_dumpitems(void)
3166 {
3167 item_p item;
3168 int i = 1;
3169 TAILQ_FOREACH(item, &ng_itemlist, all) {
3170 printf("[%d] ", i++);
3171 dumpitem(item, NULL, 0);
3172 }
3173 }
3174
3175 static void
3176 ng_dumpnodes(void)
3177 {
3178 node_p node;
3179 int i = 1;
3180 mtx_lock(&ng_nodelist_mtx);
3181 SLIST_FOREACH(node, &ng_allnodes, nd_all) {
3182 printf("[%d] ", i++);
3183 dumpnode(node, NULL, 0);
3184 }
3185 mtx_unlock(&ng_nodelist_mtx);
3186 }
3187
3188 static void
3189 ng_dumphooks(void)
3190 {
3191 hook_p hook;
3192 int i = 1;
3193 mtx_lock(&ng_nodelist_mtx);
3194 SLIST_FOREACH(hook, &ng_allhooks, hk_all) {
3195 printf("[%d] ", i++);
3196 dumphook(hook, NULL, 0);
3197 }
3198 mtx_unlock(&ng_nodelist_mtx);
3199 }
3200
3201 static int
3202 sysctl_debug_ng_dump_items(SYSCTL_HANDLER_ARGS)
3203 {
3204 int error;
3205 int val;
3206 int i;
3207
3208 val = allocated;
3209 i = 1;
3210 error = sysctl_handle_int(oidp, &val, sizeof(int), req);
3211 if (error != 0 || req->newptr == NULL)
3212 return (error);
3213 if (val == 42) {
3214 ng_dumpitems();
3215 ng_dumpnodes();
3216 ng_dumphooks();
3217 }
3218 return (0);
3219 }
3220
3221 SYSCTL_PROC(_debug, OID_AUTO, ng_dump_items, CTLTYPE_INT | CTLFLAG_RW,
3222 0, sizeof(int), sysctl_debug_ng_dump_items, "I", "Number of allocated items");
3223 #endif /* NETGRAPH_DEBUG */
3224
3225
3226 /***********************************************************************
3227 * Worklist routines
3228 **********************************************************************/
3229 /* NETISR thread enters here */
3230 /*
3231 * Pick a node off the list of nodes with work,
3232 * try get an item to process off it.
3233 * If there are no more, remove the node from the list.
3234 */
3235 static void
3236 ngintr(void)
3237 {
3238 item_p item;
3239 node_p node = NULL;
3240
3241 for (;;) {
3242 mtx_lock_spin(&ng_worklist_mtx);
3243 node = TAILQ_FIRST(&ng_worklist);
3244 if (!node) {
3245 mtx_unlock_spin(&ng_worklist_mtx);
3246 break;
3247 }
3248 node->nd_flags &= ~NGF_WORKQ;
3249 TAILQ_REMOVE(&ng_worklist, node, nd_work);
3250 mtx_unlock_spin(&ng_worklist_mtx);
3251 CTR3(KTR_NET, "%20s: node [%x] (%p) taken off worklist",
3252 __func__, node->nd_ID, node);
3253 /*
3254 * We have the node. We also take over the reference
3255 * that the list had on it.
3256 * Now process as much as you can, until it won't
3257 * let you have another item off the queue.
3258 * All this time, keep the reference
3259 * that lets us be sure that the node still exists.
3260 * Let the reference go at the last minute.
3261 * ng_dequeue will put us back on the worklist
3262 * if there is more too do. This may be of use if there
3263 * are Multiple Processors and multiple Net threads in the
3264 * future.
3265 */
3266 for (;;) {
3267 int rw;
3268
3269 mtx_lock_spin(&node->nd_input_queue.q_mtx);
3270 item = ng_dequeue(&node->nd_input_queue, &rw);
3271 if (item == NULL) {
3272 mtx_unlock_spin(&node->nd_input_queue.q_mtx);
3273 break; /* go look for another node */
3274 } else {
3275 mtx_unlock_spin(&node->nd_input_queue.q_mtx);
3276 NGI_GET_NODE(item, node); /* zaps stored node */
3277 ng_apply_item(node, item, rw);
3278 NG_NODE_UNREF(node);
3279 }
3280 }
3281 NG_NODE_UNREF(node);
3282 }
3283 }
3284
3285 static void
3286 ng_worklist_remove(node_p node)
3287 {
3288 mtx_assert(&node->nd_input_queue.q_mtx, MA_OWNED);
3289
3290 mtx_lock_spin(&ng_worklist_mtx);
3291 if (node->nd_flags & NGF_WORKQ) {
3292 node->nd_flags &= ~NGF_WORKQ;
3293 TAILQ_REMOVE(&ng_worklist, node, nd_work);
3294 mtx_unlock_spin(&ng_worklist_mtx);
3295 NG_NODE_UNREF(node);
3296 CTR3(KTR_NET, "%20s: node [%x] (%p) removed from worklist",
3297 __func__, node->nd_ID, node);
3298 } else {
3299 mtx_unlock_spin(&ng_worklist_mtx);
3300 }
3301 }
3302
3303 /*
3304 * XXX
3305 * It's posible that a debugging NG_NODE_REF may need
3306 * to be outside the mutex zone
3307 */
3308 static void
3309 ng_setisr(node_p node)
3310 {
3311
3312 mtx_assert(&node->nd_input_queue.q_mtx, MA_OWNED);
3313
3314 if ((node->nd_flags & NGF_WORKQ) == 0) {
3315 /*
3316 * If we are not already on the work queue,
3317 * then put us on.
3318 */
3319 node->nd_flags |= NGF_WORKQ;
3320 mtx_lock_spin(&ng_worklist_mtx);
3321 TAILQ_INSERT_TAIL(&ng_worklist, node, nd_work);
3322 mtx_unlock_spin(&ng_worklist_mtx);
3323 NG_NODE_REF(node); /* XXX fafe in mutex? */
3324 CTR3(KTR_NET, "%20s: node [%x] (%p) put on worklist", __func__,
3325 node->nd_ID, node);
3326 } else
3327 CTR3(KTR_NET, "%20s: node [%x] (%p) already on worklist",
3328 __func__, node->nd_ID, node);
3329 schednetisr(NETISR_NETGRAPH);
3330 }
3331
3332
3333 /***********************************************************************
3334 * Externally useable functions to set up a queue item ready for sending
3335 ***********************************************************************/
3336
3337 #ifdef NETGRAPH_DEBUG
3338 #define ITEM_DEBUG_CHECKS \
3339 do { \
3340 if (NGI_NODE(item) ) { \
3341 printf("item already has node"); \
3342 kdb_enter("has node"); \
3343 NGI_CLR_NODE(item); \
3344 } \
3345 if (NGI_HOOK(item) ) { \
3346 printf("item already has hook"); \
3347 kdb_enter("has hook"); \
3348 NGI_CLR_HOOK(item); \
3349 } \
3350 } while (0)
3351 #else
3352 #define ITEM_DEBUG_CHECKS
3353 #endif
3354
3355 /*
3356 * Put mbuf into the item.
3357 * Hook and node references will be removed when the item is dequeued.
3358 * (or equivalent)
3359 * (XXX) Unsafe because no reference held by peer on remote node.
3360 * remote node might go away in this timescale.
3361 * We know the hooks can't go away because that would require getting
3362 * a writer item on both nodes and we must have at least a reader
3363 * here to be able to do this.
3364 * Note that the hook loaded is the REMOTE hook.
3365 *
3366 * This is possibly in the critical path for new data.
3367 */
3368 item_p
3369 ng_package_data(struct mbuf *m, int flags)
3370 {
3371 item_p item;
3372
3373 if ((item = ng_getqblk(flags)) == NULL) {
3374 NG_FREE_M(m);
3375 return (NULL);
3376 }
3377 ITEM_DEBUG_CHECKS;
3378 item->el_flags = NGQF_DATA | NGQF_READER;
3379 item->el_next = NULL;
3380 NGI_M(item) = m;
3381 return (item);
3382 }
3383
3384 /*
3385 * Allocate a queue item and put items into it..
3386 * Evaluate the address as this will be needed to queue it and
3387 * to work out what some of the fields should be.
3388 * Hook and node references will be removed when the item is dequeued.
3389 * (or equivalent)
3390 */
3391 item_p
3392 ng_package_msg(struct ng_mesg *msg, int flags)
3393 {
3394 item_p item;
3395
3396 if ((item = ng_getqblk(flags)) == NULL) {
3397 NG_FREE_MSG(msg);
3398 return (NULL);
3399 }
3400 ITEM_DEBUG_CHECKS;
3401 /* Messages items count as writers unless explicitly exempted. */
3402 if (msg->header.cmd & NGM_READONLY)
3403 item->el_flags = NGQF_MESG | NGQF_READER;
3404 else
3405 item->el_flags = NGQF_MESG | NGQF_WRITER;
3406 item->el_next = NULL;
3407 /*
3408 * Set the current lasthook into the queue item
3409 */
3410 NGI_MSG(item) = msg;
3411 NGI_RETADDR(item) = 0;
3412 return (item);
3413 }
3414
3415
3416
3417 #define SET_RETADDR(item, here, retaddr) \
3418 do { /* Data or fn items don't have retaddrs */ \
3419 if ((item->el_flags & NGQF_TYPE) == NGQF_MESG) { \
3420 if (retaddr) { \
3421 NGI_RETADDR(item) = retaddr; \
3422 } else { \
3423 /* \
3424 * The old return address should be ok. \
3425 * If there isn't one, use the address \
3426 * here. \
3427 */ \
3428 if (NGI_RETADDR(item) == 0) { \
3429 NGI_RETADDR(item) \
3430 = ng_node2ID(here); \
3431 } \
3432 } \
3433 } \
3434 } while (0)
3435
3436 int
3437 ng_address_hook(node_p here, item_p item, hook_p hook, ng_ID_t retaddr)
3438 {
3439 hook_p peer;
3440 node_p peernode;
3441 ITEM_DEBUG_CHECKS;
3442 /*
3443 * Quick sanity check..
3444 * Since a hook holds a reference on it's node, once we know
3445 * that the peer is still connected (even if invalid,) we know
3446 * that the peer node is present, though maybe invalid.
3447 */
3448 if ((hook == NULL)
3449 || NG_HOOK_NOT_VALID(hook)
3450 || (NG_HOOK_PEER(hook) == NULL)
3451 || NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook))
3452 || NG_NODE_NOT_VALID(NG_PEER_NODE(hook))) {
3453 NG_FREE_ITEM(item);
3454 TRAP_ERROR();
3455 return (ENETDOWN);
3456 }
3457
3458 /*
3459 * Transfer our interest to the other (peer) end.
3460 */
3461 peer = NG_HOOK_PEER(hook);
3462 NG_HOOK_REF(peer);
3463 NGI_SET_HOOK(item, peer);
3464 peernode = NG_PEER_NODE(hook);
3465 NG_NODE_REF(peernode);
3466 NGI_SET_NODE(item, peernode);
3467 SET_RETADDR(item, here, retaddr);
3468 return (0);
3469 }
3470
3471 int
3472 ng_address_path(node_p here, item_p item, char *address, ng_ID_t retaddr)
3473 {
3474 node_p dest = NULL;
3475 hook_p hook = NULL;
3476 int error;
3477
3478 ITEM_DEBUG_CHECKS;
3479 /*
3480 * Note that ng_path2noderef increments the reference count
3481 * on the node for us if it finds one. So we don't have to.
3482 */
3483 error = ng_path2noderef(here, address, &dest, &hook);
3484 if (error) {
3485 NG_FREE_ITEM(item);
3486 return (error);
3487 }
3488 NGI_SET_NODE(item, dest);
3489 if ( hook) {
3490 NG_HOOK_REF(hook); /* don't let it go while on the queue */
3491 NGI_SET_HOOK(item, hook);
3492 }
3493 SET_RETADDR(item, here, retaddr);
3494 return (0);
3495 }
3496
3497 int
3498 ng_address_ID(node_p here, item_p item, ng_ID_t ID, ng_ID_t retaddr)
3499 {
3500 node_p dest;
3501
3502 ITEM_DEBUG_CHECKS;
3503 /*
3504 * Find the target node.
3505 */
3506 dest = ng_ID2noderef(ID); /* GETS REFERENCE! */
3507 if (dest == NULL) {
3508 NG_FREE_ITEM(item);
3509 TRAP_ERROR();
3510 return(EINVAL);
3511 }
3512 /* Fill out the contents */
3513 NGI_SET_NODE(item, dest);
3514 NGI_CLR_HOOK(item);
3515 SET_RETADDR(item, here, retaddr);
3516 return (0);
3517 }
3518
3519 /*
3520 * special case to send a message to self (e.g. destroy node)
3521 * Possibly indicate an arrival hook too.
3522 * Useful for removing that hook :-)
3523 */
3524 item_p
3525 ng_package_msg_self(node_p here, hook_p hook, struct ng_mesg *msg)
3526 {
3527 item_p item;
3528
3529 /*
3530 * Find the target node.
3531 * If there is a HOOK argument, then use that in preference
3532 * to the address.
3533 */
3534 if ((item = ng_getqblk(NG_NOFLAGS)) == NULL) {
3535 NG_FREE_MSG(msg);
3536 return (NULL);
3537 }
3538
3539 /* Fill out the contents */
3540 item->el_flags = NGQF_MESG | NGQF_WRITER;
3541 item->el_next = NULL;
3542 NG_NODE_REF(here);
3543 NGI_SET_NODE(item, here);
3544 if (hook) {
3545 NG_HOOK_REF(hook);
3546 NGI_SET_HOOK(item, hook);
3547 }
3548 NGI_MSG(item) = msg;
3549 NGI_RETADDR(item) = ng_node2ID(here);
3550 return (item);
3551 }
3552
3553 int
3554 ng_send_fn1(node_p node, hook_p hook, ng_item_fn *fn, void * arg1, int arg2,
3555 int flags)
3556 {
3557 item_p item;
3558
3559 if ((item = ng_getqblk(flags)) == NULL) {
3560 return (ENOMEM);
3561 }
3562 item->el_flags = NGQF_FN | NGQF_WRITER;
3563 NG_NODE_REF(node); /* and one for the item */
3564 NGI_SET_NODE(item, node);
3565 if (hook) {
3566 NG_HOOK_REF(hook);
3567 NGI_SET_HOOK(item, hook);
3568 }
3569 NGI_FN(item) = fn;
3570 NGI_ARG1(item) = arg1;
3571 NGI_ARG2(item) = arg2;
3572 return(ng_snd_item(item, flags));
3573 }
3574
3575 /*
3576 * Official timeout routines for Netgraph nodes.
3577 */
3578 static void
3579 ng_callout_trampoline(void *arg)
3580 {
3581 item_p item = arg;
3582
3583 ng_snd_item(item, 0);
3584 }
3585
3586
3587 int
3588 ng_callout(struct callout *c, node_p node, hook_p hook, int ticks,
3589 ng_item_fn *fn, void * arg1, int arg2)
3590 {
3591 item_p item, oitem;
3592
3593 if ((item = ng_getqblk(NG_NOFLAGS)) == NULL)
3594 return (ENOMEM);
3595
3596 item->el_flags = NGQF_FN | NGQF_WRITER;
3597 NG_NODE_REF(node); /* and one for the item */
3598 NGI_SET_NODE(item, node);
3599 if (hook) {
3600 NG_HOOK_REF(hook);
3601 NGI_SET_HOOK(item, hook);
3602 }
3603 NGI_FN(item) = fn;
3604 NGI_ARG1(item) = arg1;
3605 NGI_ARG2(item) = arg2;
3606 oitem = c->c_arg;
3607 if (callout_reset(c, ticks, &ng_callout_trampoline, item) == 1 &&
3608 oitem != NULL)
3609 NG_FREE_ITEM(oitem);
3610 return (0);
3611 }
3612
3613 /* A special modified version of untimeout() */
3614 int
3615 ng_uncallout(struct callout *c, node_p node)
3616 {
3617 item_p item;
3618 int rval;
3619
3620 KASSERT(c != NULL, ("ng_uncallout: NULL callout"));
3621 KASSERT(node != NULL, ("ng_uncallout: NULL node"));
3622
3623 rval = callout_stop(c);
3624 item = c->c_arg;
3625 /* Do an extra check */
3626 if ((rval > 0) && (c->c_func == &ng_callout_trampoline) &&
3627 (NGI_NODE(item) == node)) {
3628 /*
3629 * We successfully removed it from the queue before it ran
3630 * So now we need to unreference everything that was
3631 * given extra references. (NG_FREE_ITEM does this).
3632 */
3633 NG_FREE_ITEM(item);
3634 }
3635 c->c_arg = NULL;
3636
3637 return (rval);
3638 }
3639
3640 /*
3641 * Set the address, if none given, give the node here.
3642 */
3643 void
3644 ng_replace_retaddr(node_p here, item_p item, ng_ID_t retaddr)
3645 {
3646 if (retaddr) {
3647 NGI_RETADDR(item) = retaddr;
3648 } else {
3649 /*
3650 * The old return address should be ok.
3651 * If there isn't one, use the address here.
3652 */
3653 NGI_RETADDR(item) = ng_node2ID(here);
3654 }
3655 }
3656
3657 #define TESTING
3658 #ifdef TESTING
3659 /* just test all the macros */
3660 void
3661 ng_macro_test(item_p item);
3662 void
3663 ng_macro_test(item_p item)
3664 {
3665 node_p node = NULL;
3666 hook_p hook = NULL;
3667 struct mbuf *m;
3668 struct ng_mesg *msg;
3669 ng_ID_t retaddr;
3670 int error;
3671
3672 NGI_GET_M(item, m);
3673 NGI_GET_MSG(item, msg);
3674 retaddr = NGI_RETADDR(item);
3675 NG_SEND_DATA(error, hook, m, NULL);
3676 NG_SEND_DATA_ONLY(error, hook, m);
3677 NG_FWD_NEW_DATA(error, item, hook, m);
3678 NG_FWD_ITEM_HOOK(error, item, hook);
3679 NG_SEND_MSG_HOOK(error, node, msg, hook, retaddr);
3680 NG_SEND_MSG_ID(error, node, msg, retaddr, retaddr);
3681 NG_SEND_MSG_PATH(error, node, msg, ".:", retaddr);
3682 NG_FWD_MSG_HOOK(error, node, item, hook, retaddr);
3683 }
3684 #endif /* TESTING */
3685
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