1 /*-
2 * Copyright (c) 1996-1999 Whistle Communications, Inc.
3 * All rights reserved.
4 *
5 * Subject to the following obligations and disclaimer of warranty, use and
6 * redistribution of this software, in source or object code forms, with or
7 * without modifications are expressly permitted by Whistle Communications;
8 * provided, however, that:
9 * 1. Any and all reproductions of the source or object code must include the
10 * copyright notice above and the following disclaimer of warranties; and
11 * 2. No rights are granted, in any manner or form, to use Whistle
12 * Communications, Inc. trademarks, including the mark "WHISTLE
13 * COMMUNICATIONS" on advertising, endorsements, or otherwise except as
14 * such appears in the above copyright notice or in the software.
15 *
16 * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
17 * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
18 * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
19 * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
20 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
21 * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
22 * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
23 * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
24 * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
25 * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
26 * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
27 * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
28 * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
29 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
31 * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
32 * OF SUCH DAMAGE.
33 *
34 * Authors: Julian Elischer <julian@freebsd.org>
35 * Archie Cobbs <archie@freebsd.org>
36 *
37 * $FreeBSD$
38 * $Whistle: ng_base.c,v 1.39 1999/01/28 23:54:53 julian Exp $
39 */
40
41 /*
42 * This file implements the base netgraph code.
43 */
44
45 #include <sys/param.h>
46 #include <sys/systm.h>
47 #include <sys/ctype.h>
48 #include <sys/hash.h>
49 #include <sys/kdb.h>
50 #include <sys/kernel.h>
51 #include <sys/kthread.h>
52 #include <sys/ktr.h>
53 #include <sys/limits.h>
54 #include <sys/lock.h>
55 #include <sys/malloc.h>
56 #include <sys/mbuf.h>
57 #include <sys/proc.h>
58 #include <sys/queue.h>
59 #include <sys/refcount.h>
60 #include <sys/rwlock.h>
61 #include <sys/smp.h>
62 #include <sys/sysctl.h>
63 #include <sys/syslog.h>
64 #include <sys/unistd.h>
65 #include <machine/cpu.h>
66
67 #include <net/netisr.h>
68 #include <net/vnet.h>
69
70 #include <netgraph/ng_message.h>
71 #include <netgraph/netgraph.h>
72 #include <netgraph/ng_parse.h>
73
74 MODULE_VERSION(netgraph, NG_ABI_VERSION);
75
76 /* Mutex to protect topology events. */
77 static struct rwlock ng_topo_lock;
78 #define TOPOLOGY_RLOCK() rw_rlock(&ng_topo_lock)
79 #define TOPOLOGY_RUNLOCK() rw_runlock(&ng_topo_lock)
80 #define TOPOLOGY_WLOCK() rw_wlock(&ng_topo_lock)
81 #define TOPOLOGY_WUNLOCK() rw_wunlock(&ng_topo_lock)
82 #define TOPOLOGY_NOTOWNED() rw_assert(&ng_topo_lock, RA_UNLOCKED)
83
84 #ifdef NETGRAPH_DEBUG
85 static struct mtx ng_nodelist_mtx; /* protects global node/hook lists */
86 static struct mtx ngq_mtx; /* protects the queue item list */
87
88 static SLIST_HEAD(, ng_node) ng_allnodes;
89 static LIST_HEAD(, ng_node) ng_freenodes; /* in debug, we never free() them */
90 static SLIST_HEAD(, ng_hook) ng_allhooks;
91 static LIST_HEAD(, ng_hook) ng_freehooks; /* in debug, we never free() them */
92
93 static void ng_dumpitems(void);
94 static void ng_dumpnodes(void);
95 static void ng_dumphooks(void);
96
97 #endif /* NETGRAPH_DEBUG */
98 /*
99 * DEAD versions of the structures.
100 * In order to avoid races, it is sometimes neccesary to point
101 * at SOMETHING even though theoretically, the current entity is
102 * INVALID. Use these to avoid these races.
103 */
104 struct ng_type ng_deadtype = {
105 NG_ABI_VERSION,
106 "dead",
107 NULL, /* modevent */
108 NULL, /* constructor */
109 NULL, /* rcvmsg */
110 NULL, /* shutdown */
111 NULL, /* newhook */
112 NULL, /* findhook */
113 NULL, /* connect */
114 NULL, /* rcvdata */
115 NULL, /* disconnect */
116 NULL, /* cmdlist */
117 };
118
119 struct ng_node ng_deadnode = {
120 "dead",
121 &ng_deadtype,
122 NGF_INVALID,
123 0, /* numhooks */
124 NULL, /* private */
125 0, /* ID */
126 LIST_HEAD_INITIALIZER(ng_deadnode.nd_hooks),
127 {}, /* all_nodes list entry */
128 {}, /* id hashtable list entry */
129 { 0,
130 0,
131 {}, /* should never use! (should hang) */
132 {}, /* workqueue entry */
133 STAILQ_HEAD_INITIALIZER(ng_deadnode.nd_input_queue.queue),
134 },
135 1, /* refs */
136 NULL, /* vnet */
137 #ifdef NETGRAPH_DEBUG
138 ND_MAGIC,
139 __FILE__,
140 __LINE__,
141 {NULL}
142 #endif /* NETGRAPH_DEBUG */
143 };
144
145 struct ng_hook ng_deadhook = {
146 "dead",
147 NULL, /* private */
148 HK_INVALID | HK_DEAD,
149 0, /* undefined data link type */
150 &ng_deadhook, /* Peer is self */
151 &ng_deadnode, /* attached to deadnode */
152 {}, /* hooks list */
153 NULL, /* override rcvmsg() */
154 NULL, /* override rcvdata() */
155 1, /* refs always >= 1 */
156 #ifdef NETGRAPH_DEBUG
157 HK_MAGIC,
158 __FILE__,
159 __LINE__,
160 {NULL}
161 #endif /* NETGRAPH_DEBUG */
162 };
163
164 /*
165 * END DEAD STRUCTURES
166 */
167 /* List nodes with unallocated work */
168 static STAILQ_HEAD(, ng_node) ng_worklist = STAILQ_HEAD_INITIALIZER(ng_worklist);
169 static struct mtx ng_worklist_mtx; /* MUST LOCK NODE FIRST */
170
171 /* List of installed types */
172 static LIST_HEAD(, ng_type) ng_typelist;
173 static struct rwlock ng_typelist_lock;
174 #define TYPELIST_RLOCK() rw_rlock(&ng_typelist_lock)
175 #define TYPELIST_RUNLOCK() rw_runlock(&ng_typelist_lock)
176 #define TYPELIST_WLOCK() rw_wlock(&ng_typelist_lock)
177 #define TYPELIST_WUNLOCK() rw_wunlock(&ng_typelist_lock)
178
179 /* Hash related definitions. */
180 LIST_HEAD(nodehash, ng_node);
181 static VNET_DEFINE(struct nodehash *, ng_ID_hash);
182 static VNET_DEFINE(u_long, ng_ID_hmask);
183 static VNET_DEFINE(u_long, ng_nodes);
184 static VNET_DEFINE(struct nodehash *, ng_name_hash);
185 static VNET_DEFINE(u_long, ng_name_hmask);
186 static VNET_DEFINE(u_long, ng_named_nodes);
187 #define V_ng_ID_hash VNET(ng_ID_hash)
188 #define V_ng_ID_hmask VNET(ng_ID_hmask)
189 #define V_ng_nodes VNET(ng_nodes)
190 #define V_ng_name_hash VNET(ng_name_hash)
191 #define V_ng_name_hmask VNET(ng_name_hmask)
192 #define V_ng_named_nodes VNET(ng_named_nodes)
193
194 static struct rwlock ng_idhash_lock;
195 #define IDHASH_RLOCK() rw_rlock(&ng_idhash_lock)
196 #define IDHASH_RUNLOCK() rw_runlock(&ng_idhash_lock)
197 #define IDHASH_WLOCK() rw_wlock(&ng_idhash_lock)
198 #define IDHASH_WUNLOCK() rw_wunlock(&ng_idhash_lock)
199
200 /* Method to find a node.. used twice so do it here */
201 #define NG_IDHASH_FN(ID) ((ID) % (V_ng_ID_hmask + 1))
202 #define NG_IDHASH_FIND(ID, node) \
203 do { \
204 rw_assert(&ng_idhash_lock, RA_LOCKED); \
205 LIST_FOREACH(node, &V_ng_ID_hash[NG_IDHASH_FN(ID)], \
206 nd_idnodes) { \
207 if (NG_NODE_IS_VALID(node) \
208 && (NG_NODE_ID(node) == ID)) { \
209 break; \
210 } \
211 } \
212 } while (0)
213
214 static struct rwlock ng_namehash_lock;
215 #define NAMEHASH_RLOCK() rw_rlock(&ng_namehash_lock)
216 #define NAMEHASH_RUNLOCK() rw_runlock(&ng_namehash_lock)
217 #define NAMEHASH_WLOCK() rw_wlock(&ng_namehash_lock)
218 #define NAMEHASH_WUNLOCK() rw_wunlock(&ng_namehash_lock)
219
220 /* Internal functions */
221 static int ng_add_hook(node_p node, const char *name, hook_p * hookp);
222 static int ng_generic_msg(node_p here, item_p item, hook_p lasthook);
223 static ng_ID_t ng_decodeidname(const char *name);
224 static int ngb_mod_event(module_t mod, int event, void *data);
225 static void ng_worklist_add(node_p node);
226 static void ngthread(void *);
227 static int ng_apply_item(node_p node, item_p item, int rw);
228 static void ng_flush_input_queue(node_p node);
229 static node_p ng_ID2noderef(ng_ID_t ID);
230 static int ng_con_nodes(item_p item, node_p node, const char *name,
231 node_p node2, const char *name2);
232 static int ng_con_part2(node_p node, item_p item, hook_p hook);
233 static int ng_con_part3(node_p node, item_p item, hook_p hook);
234 static int ng_mkpeer(node_p node, const char *name, const char *name2,
235 char *type);
236 static void ng_name_rehash(void);
237 static void ng_ID_rehash(void);
238
239 /* Imported, these used to be externally visible, some may go back. */
240 void ng_destroy_hook(hook_p hook);
241 int ng_path2noderef(node_p here, const char *path,
242 node_p *dest, hook_p *lasthook);
243 int ng_make_node(const char *type, node_p *nodepp);
244 int ng_path_parse(char *addr, char **node, char **path, char **hook);
245 void ng_rmnode(node_p node, hook_p dummy1, void *dummy2, int dummy3);
246 void ng_unname(node_p node);
247
248 /* Our own netgraph malloc type */
249 MALLOC_DEFINE(M_NETGRAPH, "netgraph", "netgraph structures and ctrl messages");
250 MALLOC_DEFINE(M_NETGRAPH_MSG, "netgraph_msg", "netgraph name storage");
251 static MALLOC_DEFINE(M_NETGRAPH_HOOK, "netgraph_hook",
252 "netgraph hook structures");
253 static MALLOC_DEFINE(M_NETGRAPH_NODE, "netgraph_node",
254 "netgraph node structures");
255 static MALLOC_DEFINE(M_NETGRAPH_ITEM, "netgraph_item",
256 "netgraph item structures");
257
258 /* Should not be visible outside this file */
259
260 #define _NG_ALLOC_HOOK(hook) \
261 hook = malloc(sizeof(*hook), M_NETGRAPH_HOOK, M_NOWAIT | M_ZERO)
262 #define _NG_ALLOC_NODE(node) \
263 node = malloc(sizeof(*node), M_NETGRAPH_NODE, M_NOWAIT | M_ZERO)
264
265 #define NG_QUEUE_LOCK_INIT(n) \
266 mtx_init(&(n)->q_mtx, "ng_node", NULL, MTX_DEF)
267 #define NG_QUEUE_LOCK(n) \
268 mtx_lock(&(n)->q_mtx)
269 #define NG_QUEUE_UNLOCK(n) \
270 mtx_unlock(&(n)->q_mtx)
271 #define NG_WORKLIST_LOCK_INIT() \
272 mtx_init(&ng_worklist_mtx, "ng_worklist", NULL, MTX_DEF)
273 #define NG_WORKLIST_LOCK() \
274 mtx_lock(&ng_worklist_mtx)
275 #define NG_WORKLIST_UNLOCK() \
276 mtx_unlock(&ng_worklist_mtx)
277 #define NG_WORKLIST_SLEEP() \
278 mtx_sleep(&ng_worklist, &ng_worklist_mtx, PI_NET, "sleep", 0)
279 #define NG_WORKLIST_WAKEUP() \
280 wakeup_one(&ng_worklist)
281
282 #ifdef NETGRAPH_DEBUG /*----------------------------------------------*/
283 /*
284 * In debug mode:
285 * In an attempt to help track reference count screwups
286 * we do not free objects back to the malloc system, but keep them
287 * in a local cache where we can examine them and keep information safely
288 * after they have been freed.
289 * We use this scheme for nodes and hooks, and to some extent for items.
290 */
291 static __inline hook_p
292 ng_alloc_hook(void)
293 {
294 hook_p hook;
295 SLIST_ENTRY(ng_hook) temp;
296 mtx_lock(&ng_nodelist_mtx);
297 hook = LIST_FIRST(&ng_freehooks);
298 if (hook) {
299 LIST_REMOVE(hook, hk_hooks);
300 bcopy(&hook->hk_all, &temp, sizeof(temp));
301 bzero(hook, sizeof(struct ng_hook));
302 bcopy(&temp, &hook->hk_all, sizeof(temp));
303 mtx_unlock(&ng_nodelist_mtx);
304 hook->hk_magic = HK_MAGIC;
305 } else {
306 mtx_unlock(&ng_nodelist_mtx);
307 _NG_ALLOC_HOOK(hook);
308 if (hook) {
309 hook->hk_magic = HK_MAGIC;
310 mtx_lock(&ng_nodelist_mtx);
311 SLIST_INSERT_HEAD(&ng_allhooks, hook, hk_all);
312 mtx_unlock(&ng_nodelist_mtx);
313 }
314 }
315 return (hook);
316 }
317
318 static __inline node_p
319 ng_alloc_node(void)
320 {
321 node_p node;
322 SLIST_ENTRY(ng_node) temp;
323 mtx_lock(&ng_nodelist_mtx);
324 node = LIST_FIRST(&ng_freenodes);
325 if (node) {
326 LIST_REMOVE(node, nd_nodes);
327 bcopy(&node->nd_all, &temp, sizeof(temp));
328 bzero(node, sizeof(struct ng_node));
329 bcopy(&temp, &node->nd_all, sizeof(temp));
330 mtx_unlock(&ng_nodelist_mtx);
331 node->nd_magic = ND_MAGIC;
332 } else {
333 mtx_unlock(&ng_nodelist_mtx);
334 _NG_ALLOC_NODE(node);
335 if (node) {
336 node->nd_magic = ND_MAGIC;
337 mtx_lock(&ng_nodelist_mtx);
338 SLIST_INSERT_HEAD(&ng_allnodes, node, nd_all);
339 mtx_unlock(&ng_nodelist_mtx);
340 }
341 }
342 return (node);
343 }
344
345 #define NG_ALLOC_HOOK(hook) do { (hook) = ng_alloc_hook(); } while (0)
346 #define NG_ALLOC_NODE(node) do { (node) = ng_alloc_node(); } while (0)
347
348 #define NG_FREE_HOOK(hook) \
349 do { \
350 mtx_lock(&ng_nodelist_mtx); \
351 LIST_INSERT_HEAD(&ng_freehooks, hook, hk_hooks); \
352 hook->hk_magic = 0; \
353 mtx_unlock(&ng_nodelist_mtx); \
354 } while (0)
355
356 #define NG_FREE_NODE(node) \
357 do { \
358 mtx_lock(&ng_nodelist_mtx); \
359 LIST_INSERT_HEAD(&ng_freenodes, node, nd_nodes); \
360 node->nd_magic = 0; \
361 mtx_unlock(&ng_nodelist_mtx); \
362 } while (0)
363
364 #else /* NETGRAPH_DEBUG */ /*----------------------------------------------*/
365
366 #define NG_ALLOC_HOOK(hook) _NG_ALLOC_HOOK(hook)
367 #define NG_ALLOC_NODE(node) _NG_ALLOC_NODE(node)
368
369 #define NG_FREE_HOOK(hook) do { free((hook), M_NETGRAPH_HOOK); } while (0)
370 #define NG_FREE_NODE(node) do { free((node), M_NETGRAPH_NODE); } while (0)
371
372 #endif /* NETGRAPH_DEBUG */ /*----------------------------------------------*/
373
374 /* Set this to kdb_enter("X") to catch all errors as they occur */
375 #ifndef TRAP_ERROR
376 #define TRAP_ERROR()
377 #endif
378
379 static VNET_DEFINE(ng_ID_t, nextID) = 1;
380 #define V_nextID VNET(nextID)
381
382 #ifdef INVARIANTS
383 #define CHECK_DATA_MBUF(m) do { \
384 struct mbuf *n; \
385 int total; \
386 \
387 M_ASSERTPKTHDR(m); \
388 for (total = 0, n = (m); n != NULL; n = n->m_next) { \
389 total += n->m_len; \
390 if (n->m_nextpkt != NULL) \
391 panic("%s: m_nextpkt", __func__); \
392 } \
393 \
394 if ((m)->m_pkthdr.len != total) { \
395 panic("%s: %d != %d", \
396 __func__, (m)->m_pkthdr.len, total); \
397 } \
398 } while (0)
399 #else
400 #define CHECK_DATA_MBUF(m)
401 #endif
402
403 #define ERROUT(x) do { error = (x); goto done; } while (0)
404
405 /************************************************************************
406 Parse type definitions for generic messages
407 ************************************************************************/
408
409 /* Handy structure parse type defining macro */
410 #define DEFINE_PARSE_STRUCT_TYPE(lo, up, args) \
411 static const struct ng_parse_struct_field \
412 ng_ ## lo ## _type_fields[] = NG_GENERIC_ ## up ## _INFO args; \
413 static const struct ng_parse_type ng_generic_ ## lo ## _type = { \
414 &ng_parse_struct_type, \
415 &ng_ ## lo ## _type_fields \
416 }
417
418 DEFINE_PARSE_STRUCT_TYPE(mkpeer, MKPEER, ());
419 DEFINE_PARSE_STRUCT_TYPE(connect, CONNECT, ());
420 DEFINE_PARSE_STRUCT_TYPE(name, NAME, ());
421 DEFINE_PARSE_STRUCT_TYPE(rmhook, RMHOOK, ());
422 DEFINE_PARSE_STRUCT_TYPE(nodeinfo, NODEINFO, ());
423 DEFINE_PARSE_STRUCT_TYPE(typeinfo, TYPEINFO, ());
424 DEFINE_PARSE_STRUCT_TYPE(linkinfo, LINKINFO, (&ng_generic_nodeinfo_type));
425
426 /* Get length of an array when the length is stored as a 32 bit
427 value immediately preceding the array -- as with struct namelist
428 and struct typelist. */
429 static int
430 ng_generic_list_getLength(const struct ng_parse_type *type,
431 const u_char *start, const u_char *buf)
432 {
433 return *((const u_int32_t *)(buf - 4));
434 }
435
436 /* Get length of the array of struct linkinfo inside a struct hooklist */
437 static int
438 ng_generic_linkinfo_getLength(const struct ng_parse_type *type,
439 const u_char *start, const u_char *buf)
440 {
441 const struct hooklist *hl = (const struct hooklist *)start;
442
443 return hl->nodeinfo.hooks;
444 }
445
446 /* Array type for a variable length array of struct namelist */
447 static const struct ng_parse_array_info ng_nodeinfoarray_type_info = {
448 &ng_generic_nodeinfo_type,
449 &ng_generic_list_getLength
450 };
451 static const struct ng_parse_type ng_generic_nodeinfoarray_type = {
452 &ng_parse_array_type,
453 &ng_nodeinfoarray_type_info
454 };
455
456 /* Array type for a variable length array of struct typelist */
457 static const struct ng_parse_array_info ng_typeinfoarray_type_info = {
458 &ng_generic_typeinfo_type,
459 &ng_generic_list_getLength
460 };
461 static const struct ng_parse_type ng_generic_typeinfoarray_type = {
462 &ng_parse_array_type,
463 &ng_typeinfoarray_type_info
464 };
465
466 /* Array type for array of struct linkinfo in struct hooklist */
467 static const struct ng_parse_array_info ng_generic_linkinfo_array_type_info = {
468 &ng_generic_linkinfo_type,
469 &ng_generic_linkinfo_getLength
470 };
471 static const struct ng_parse_type ng_generic_linkinfo_array_type = {
472 &ng_parse_array_type,
473 &ng_generic_linkinfo_array_type_info
474 };
475
476 DEFINE_PARSE_STRUCT_TYPE(typelist, TYPELIST, (&ng_generic_typeinfoarray_type));
477 DEFINE_PARSE_STRUCT_TYPE(hooklist, HOOKLIST,
478 (&ng_generic_nodeinfo_type, &ng_generic_linkinfo_array_type));
479 DEFINE_PARSE_STRUCT_TYPE(listnodes, LISTNODES,
480 (&ng_generic_nodeinfoarray_type));
481
482 /* List of commands and how to convert arguments to/from ASCII */
483 static const struct ng_cmdlist ng_generic_cmds[] = {
484 {
485 NGM_GENERIC_COOKIE,
486 NGM_SHUTDOWN,
487 "shutdown",
488 NULL,
489 NULL
490 },
491 {
492 NGM_GENERIC_COOKIE,
493 NGM_MKPEER,
494 "mkpeer",
495 &ng_generic_mkpeer_type,
496 NULL
497 },
498 {
499 NGM_GENERIC_COOKIE,
500 NGM_CONNECT,
501 "connect",
502 &ng_generic_connect_type,
503 NULL
504 },
505 {
506 NGM_GENERIC_COOKIE,
507 NGM_NAME,
508 "name",
509 &ng_generic_name_type,
510 NULL
511 },
512 {
513 NGM_GENERIC_COOKIE,
514 NGM_RMHOOK,
515 "rmhook",
516 &ng_generic_rmhook_type,
517 NULL
518 },
519 {
520 NGM_GENERIC_COOKIE,
521 NGM_NODEINFO,
522 "nodeinfo",
523 NULL,
524 &ng_generic_nodeinfo_type
525 },
526 {
527 NGM_GENERIC_COOKIE,
528 NGM_LISTHOOKS,
529 "listhooks",
530 NULL,
531 &ng_generic_hooklist_type
532 },
533 {
534 NGM_GENERIC_COOKIE,
535 NGM_LISTNAMES,
536 "listnames",
537 NULL,
538 &ng_generic_listnodes_type /* same as NGM_LISTNODES */
539 },
540 {
541 NGM_GENERIC_COOKIE,
542 NGM_LISTNODES,
543 "listnodes",
544 NULL,
545 &ng_generic_listnodes_type
546 },
547 {
548 NGM_GENERIC_COOKIE,
549 NGM_LISTTYPES,
550 "listtypes",
551 NULL,
552 &ng_generic_typelist_type
553 },
554 {
555 NGM_GENERIC_COOKIE,
556 NGM_TEXT_CONFIG,
557 "textconfig",
558 NULL,
559 &ng_parse_string_type
560 },
561 {
562 NGM_GENERIC_COOKIE,
563 NGM_TEXT_STATUS,
564 "textstatus",
565 NULL,
566 &ng_parse_string_type
567 },
568 {
569 NGM_GENERIC_COOKIE,
570 NGM_ASCII2BINARY,
571 "ascii2binary",
572 &ng_parse_ng_mesg_type,
573 &ng_parse_ng_mesg_type
574 },
575 {
576 NGM_GENERIC_COOKIE,
577 NGM_BINARY2ASCII,
578 "binary2ascii",
579 &ng_parse_ng_mesg_type,
580 &ng_parse_ng_mesg_type
581 },
582 { 0 }
583 };
584
585 /************************************************************************
586 Node routines
587 ************************************************************************/
588
589 /*
590 * Instantiate a node of the requested type
591 */
592 int
593 ng_make_node(const char *typename, node_p *nodepp)
594 {
595 struct ng_type *type;
596 int error;
597
598 /* Check that the type makes sense */
599 if (typename == NULL) {
600 TRAP_ERROR();
601 return (EINVAL);
602 }
603
604 /* Locate the node type. If we fail we return. Do not try to load
605 * module.
606 */
607 if ((type = ng_findtype(typename)) == NULL)
608 return (ENXIO);
609
610 /*
611 * If we have a constructor, then make the node and
612 * call the constructor to do type specific initialisation.
613 */
614 if (type->constructor != NULL) {
615 if ((error = ng_make_node_common(type, nodepp)) == 0) {
616 if ((error = ((*type->constructor)(*nodepp))) != 0) {
617 NG_NODE_UNREF(*nodepp);
618 }
619 }
620 } else {
621 /*
622 * Node has no constructor. We cannot ask for one
623 * to be made. It must be brought into existence by
624 * some external agency. The external agency should
625 * call ng_make_node_common() directly to get the
626 * netgraph part initialised.
627 */
628 TRAP_ERROR();
629 error = EINVAL;
630 }
631 return (error);
632 }
633
634 /*
635 * Generic node creation. Called by node initialisation for externally
636 * instantiated nodes (e.g. hardware, sockets, etc ).
637 * The returned node has a reference count of 1.
638 */
639 int
640 ng_make_node_common(struct ng_type *type, node_p *nodepp)
641 {
642 node_p node;
643
644 /* Require the node type to have been already installed */
645 if (ng_findtype(type->name) == NULL) {
646 TRAP_ERROR();
647 return (EINVAL);
648 }
649
650 /* Make a node and try attach it to the type */
651 NG_ALLOC_NODE(node);
652 if (node == NULL) {
653 TRAP_ERROR();
654 return (ENOMEM);
655 }
656 node->nd_type = type;
657 #ifdef VIMAGE
658 node->nd_vnet = curvnet;
659 #endif
660 NG_NODE_REF(node); /* note reference */
661 type->refs++;
662
663 NG_QUEUE_LOCK_INIT(&node->nd_input_queue);
664 STAILQ_INIT(&node->nd_input_queue.queue);
665 node->nd_input_queue.q_flags = 0;
666
667 /* Initialize hook list for new node */
668 LIST_INIT(&node->nd_hooks);
669
670 /* Get an ID and put us in the hash chain. */
671 IDHASH_WLOCK();
672 for (;;) { /* wrap protection, even if silly */
673 node_p node2 = NULL;
674 node->nd_ID = V_nextID++; /* 137/sec for 1 year before wrap */
675
676 /* Is there a problem with the new number? */
677 NG_IDHASH_FIND(node->nd_ID, node2); /* already taken? */
678 if ((node->nd_ID != 0) && (node2 == NULL)) {
679 break;
680 }
681 }
682 V_ng_nodes++;
683 if (V_ng_nodes * 2 > V_ng_ID_hmask)
684 ng_ID_rehash();
685 LIST_INSERT_HEAD(&V_ng_ID_hash[NG_IDHASH_FN(node->nd_ID)], node,
686 nd_idnodes);
687 IDHASH_WUNLOCK();
688
689 /* Done */
690 *nodepp = node;
691 return (0);
692 }
693
694 /*
695 * Forceably start the shutdown process on a node. Either call
696 * its shutdown method, or do the default shutdown if there is
697 * no type-specific method.
698 *
699 * We can only be called from a shutdown message, so we know we have
700 * a writer lock, and therefore exclusive access. It also means
701 * that we should not be on the work queue, but we check anyhow.
702 *
703 * Persistent node types must have a type-specific method which
704 * allocates a new node in which case, this one is irretrievably going away,
705 * or cleans up anything it needs, and just makes the node valid again,
706 * in which case we allow the node to survive.
707 *
708 * XXX We need to think of how to tell a persistent node that we
709 * REALLY need to go away because the hardware has gone or we
710 * are rebooting.... etc.
711 */
712 void
713 ng_rmnode(node_p node, hook_p dummy1, void *dummy2, int dummy3)
714 {
715 hook_p hook;
716
717 /* Check if it's already shutting down */
718 if ((node->nd_flags & NGF_CLOSING) != 0)
719 return;
720
721 if (node == &ng_deadnode) {
722 printf ("shutdown called on deadnode\n");
723 return;
724 }
725
726 /* Add an extra reference so it doesn't go away during this */
727 NG_NODE_REF(node);
728
729 /*
730 * Mark it invalid so any newcomers know not to try use it
731 * Also add our own mark so we can't recurse
732 * note that NGF_INVALID does not do this as it's also set during
733 * creation
734 */
735 node->nd_flags |= NGF_INVALID|NGF_CLOSING;
736
737 /* If node has its pre-shutdown method, then call it first*/
738 if (node->nd_type && node->nd_type->close)
739 (*node->nd_type->close)(node);
740
741 /* Notify all remaining connected nodes to disconnect */
742 while ((hook = LIST_FIRST(&node->nd_hooks)) != NULL)
743 ng_destroy_hook(hook);
744
745 /*
746 * Drain the input queue forceably.
747 * it has no hooks so what's it going to do, bleed on someone?
748 * Theoretically we came here from a queue entry that was added
749 * Just before the queue was closed, so it should be empty anyway.
750 * Also removes us from worklist if needed.
751 */
752 ng_flush_input_queue(node);
753
754 /* Ask the type if it has anything to do in this case */
755 if (node->nd_type && node->nd_type->shutdown) {
756 (*node->nd_type->shutdown)(node);
757 if (NG_NODE_IS_VALID(node)) {
758 /*
759 * Well, blow me down if the node code hasn't declared
760 * that it doesn't want to die.
761 * Presumably it is a persistant node.
762 * If we REALLY want it to go away,
763 * e.g. hardware going away,
764 * Our caller should set NGF_REALLY_DIE in nd_flags.
765 */
766 node->nd_flags &= ~(NGF_INVALID|NGF_CLOSING);
767 NG_NODE_UNREF(node); /* Assume they still have theirs */
768 return;
769 }
770 } else { /* do the default thing */
771 NG_NODE_UNREF(node);
772 }
773
774 ng_unname(node); /* basically a NOP these days */
775
776 /*
777 * Remove extra reference, possibly the last
778 * Possible other holders of references may include
779 * timeout callouts, but theoretically the node's supposed to
780 * have cancelled them. Possibly hardware dependencies may
781 * force a driver to 'linger' with a reference.
782 */
783 NG_NODE_UNREF(node);
784 }
785
786 /*
787 * Remove a reference to the node, possibly the last.
788 * deadnode always acts as it it were the last.
789 */
790 void
791 ng_unref_node(node_p node)
792 {
793
794 if (node == &ng_deadnode)
795 return;
796
797 CURVNET_SET(node->nd_vnet);
798
799 if (refcount_release(&node->nd_refs)) { /* we were the last */
800
801 node->nd_type->refs--; /* XXX maybe should get types lock? */
802 NAMEHASH_WLOCK();
803 if (NG_NODE_HAS_NAME(node)) {
804 V_ng_named_nodes--;
805 LIST_REMOVE(node, nd_nodes);
806 }
807 NAMEHASH_WUNLOCK();
808
809 IDHASH_WLOCK();
810 V_ng_nodes--;
811 LIST_REMOVE(node, nd_idnodes);
812 IDHASH_WUNLOCK();
813
814 mtx_destroy(&node->nd_input_queue.q_mtx);
815 NG_FREE_NODE(node);
816 }
817 CURVNET_RESTORE();
818 }
819
820 /************************************************************************
821 Node ID handling
822 ************************************************************************/
823 static node_p
824 ng_ID2noderef(ng_ID_t ID)
825 {
826 node_p node;
827
828 IDHASH_RLOCK();
829 NG_IDHASH_FIND(ID, node);
830 if (node)
831 NG_NODE_REF(node);
832 IDHASH_RUNLOCK();
833 return(node);
834 }
835
836 ng_ID_t
837 ng_node2ID(node_p node)
838 {
839 return (node ? NG_NODE_ID(node) : 0);
840 }
841
842 /************************************************************************
843 Node name handling
844 ************************************************************************/
845
846 /*
847 * Assign a node a name.
848 */
849 int
850 ng_name_node(node_p node, const char *name)
851 {
852 uint32_t hash;
853 node_p node2;
854 int i;
855
856 /* Check the name is valid */
857 for (i = 0; i < NG_NODESIZ; i++) {
858 if (name[i] == '\0' || name[i] == '.' || name[i] == ':')
859 break;
860 }
861 if (i == 0 || name[i] != '\0') {
862 TRAP_ERROR();
863 return (EINVAL);
864 }
865 if (ng_decodeidname(name) != 0) { /* valid IDs not allowed here */
866 TRAP_ERROR();
867 return (EINVAL);
868 }
869
870 NAMEHASH_WLOCK();
871 if (V_ng_named_nodes * 2 > V_ng_name_hmask)
872 ng_name_rehash();
873
874 hash = hash32_str(name, HASHINIT) & V_ng_name_hmask;
875 /* Check the name isn't already being used. */
876 LIST_FOREACH(node2, &V_ng_name_hash[hash], nd_nodes)
877 if (NG_NODE_IS_VALID(node2) &&
878 (strcmp(NG_NODE_NAME(node2), name) == 0)) {
879 NAMEHASH_WUNLOCK();
880 return (EADDRINUSE);
881 }
882
883 if (NG_NODE_HAS_NAME(node))
884 LIST_REMOVE(node, nd_nodes);
885 else
886 V_ng_named_nodes++;
887 /* Copy it. */
888 strlcpy(NG_NODE_NAME(node), name, NG_NODESIZ);
889 /* Update name hash. */
890 LIST_INSERT_HEAD(&V_ng_name_hash[hash], node, nd_nodes);
891 NAMEHASH_WUNLOCK();
892
893 return (0);
894 }
895
896 /*
897 * Find a node by absolute name. The name should NOT end with ':'
898 * The name "." means "this node" and "[xxx]" means "the node
899 * with ID (ie, at address) xxx".
900 *
901 * Returns the node if found, else NULL.
902 * Eventually should add something faster than a sequential search.
903 * Note it acquires a reference on the node so you can be sure it's still
904 * there.
905 */
906 node_p
907 ng_name2noderef(node_p here, const char *name)
908 {
909 node_p node;
910 ng_ID_t temp;
911 int hash;
912
913 /* "." means "this node" */
914 if (strcmp(name, ".") == 0) {
915 NG_NODE_REF(here);
916 return(here);
917 }
918
919 /* Check for name-by-ID */
920 if ((temp = ng_decodeidname(name)) != 0) {
921 return (ng_ID2noderef(temp));
922 }
923
924 /* Find node by name. */
925 hash = hash32_str(name, HASHINIT) & V_ng_name_hmask;
926 NAMEHASH_RLOCK();
927 LIST_FOREACH(node, &V_ng_name_hash[hash], nd_nodes)
928 if (NG_NODE_IS_VALID(node) &&
929 (strcmp(NG_NODE_NAME(node), name) == 0)) {
930 NG_NODE_REF(node);
931 break;
932 }
933 NAMEHASH_RUNLOCK();
934
935 return (node);
936 }
937
938 /*
939 * Decode an ID name, eg. "[f03034de]". Returns 0 if the
940 * string is not valid, otherwise returns the value.
941 */
942 static ng_ID_t
943 ng_decodeidname(const char *name)
944 {
945 const int len = strlen(name);
946 char *eptr;
947 u_long val;
948
949 /* Check for proper length, brackets, no leading junk */
950 if ((len < 3) || (name[0] != '[') || (name[len - 1] != ']') ||
951 (!isxdigit(name[1])))
952 return ((ng_ID_t)0);
953
954 /* Decode number */
955 val = strtoul(name + 1, &eptr, 16);
956 if ((eptr - name != len - 1) || (val == ULONG_MAX) || (val == 0))
957 return ((ng_ID_t)0);
958
959 return ((ng_ID_t)val);
960 }
961
962 /*
963 * Remove a name from a node. This should only be called
964 * when shutting down and removing the node.
965 */
966 void
967 ng_unname(node_p node)
968 {
969 }
970
971 /*
972 * Allocate a bigger name hash.
973 */
974 static void
975 ng_name_rehash()
976 {
977 struct nodehash *new;
978 uint32_t hash;
979 u_long hmask;
980 node_p node, node2;
981 int i;
982
983 new = hashinit_flags((V_ng_name_hmask + 1) * 2, M_NETGRAPH_NODE, &hmask,
984 HASH_NOWAIT);
985 if (new == NULL)
986 return;
987
988 for (i = 0; i <= V_ng_name_hmask; i++)
989 LIST_FOREACH_SAFE(node, &V_ng_name_hash[i], nd_nodes, node2) {
990 #ifdef INVARIANTS
991 LIST_REMOVE(node, nd_nodes);
992 #endif
993 hash = hash32_str(NG_NODE_NAME(node), HASHINIT) & hmask;
994 LIST_INSERT_HEAD(&new[hash], node, nd_nodes);
995 }
996
997 hashdestroy(V_ng_name_hash, M_NETGRAPH_NODE, V_ng_name_hmask);
998 V_ng_name_hash = new;
999 V_ng_name_hmask = hmask;
1000 }
1001
1002 /*
1003 * Allocate a bigger ID hash.
1004 */
1005 static void
1006 ng_ID_rehash()
1007 {
1008 struct nodehash *new;
1009 uint32_t hash;
1010 u_long hmask;
1011 node_p node, node2;
1012 int i;
1013
1014 new = hashinit_flags((V_ng_ID_hmask + 1) * 2, M_NETGRAPH_NODE, &hmask,
1015 HASH_NOWAIT);
1016 if (new == NULL)
1017 return;
1018
1019 for (i = 0; i <= V_ng_ID_hmask; i++)
1020 LIST_FOREACH_SAFE(node, &V_ng_ID_hash[i], nd_idnodes, node2) {
1021 #ifdef INVARIANTS
1022 LIST_REMOVE(node, nd_idnodes);
1023 #endif
1024 hash = (node->nd_ID % (hmask + 1));
1025 LIST_INSERT_HEAD(&new[hash], node, nd_idnodes);
1026 }
1027
1028 hashdestroy(V_ng_ID_hash, M_NETGRAPH_NODE, V_ng_name_hmask);
1029 V_ng_ID_hash = new;
1030 V_ng_ID_hmask = hmask;
1031 }
1032
1033 /************************************************************************
1034 Hook routines
1035 Names are not optional. Hooks are always connected, except for a
1036 brief moment within these routines. On invalidation or during creation
1037 they are connected to the 'dead' hook.
1038 ************************************************************************/
1039
1040 /*
1041 * Remove a hook reference
1042 */
1043 void
1044 ng_unref_hook(hook_p hook)
1045 {
1046
1047 if (hook == &ng_deadhook)
1048 return;
1049
1050 if (refcount_release(&hook->hk_refs)) { /* we were the last */
1051 if (_NG_HOOK_NODE(hook)) /* it'll probably be ng_deadnode */
1052 _NG_NODE_UNREF((_NG_HOOK_NODE(hook)));
1053 NG_FREE_HOOK(hook);
1054 }
1055 }
1056
1057 /*
1058 * Add an unconnected hook to a node. Only used internally.
1059 * Assumes node is locked. (XXX not yet true )
1060 */
1061 static int
1062 ng_add_hook(node_p node, const char *name, hook_p *hookp)
1063 {
1064 hook_p hook;
1065 int error = 0;
1066
1067 /* Check that the given name is good */
1068 if (name == NULL) {
1069 TRAP_ERROR();
1070 return (EINVAL);
1071 }
1072 if (ng_findhook(node, name) != NULL) {
1073 TRAP_ERROR();
1074 return (EEXIST);
1075 }
1076
1077 /* Allocate the hook and link it up */
1078 NG_ALLOC_HOOK(hook);
1079 if (hook == NULL) {
1080 TRAP_ERROR();
1081 return (ENOMEM);
1082 }
1083 hook->hk_refs = 1; /* add a reference for us to return */
1084 hook->hk_flags = HK_INVALID;
1085 hook->hk_peer = &ng_deadhook; /* start off this way */
1086 hook->hk_node = node;
1087 NG_NODE_REF(node); /* each hook counts as a reference */
1088
1089 /* Set hook name */
1090 strlcpy(NG_HOOK_NAME(hook), name, NG_HOOKSIZ);
1091
1092 /*
1093 * Check if the node type code has something to say about it
1094 * If it fails, the unref of the hook will also unref the node.
1095 */
1096 if (node->nd_type->newhook != NULL) {
1097 if ((error = (*node->nd_type->newhook)(node, hook, name))) {
1098 NG_HOOK_UNREF(hook); /* this frees the hook */
1099 return (error);
1100 }
1101 }
1102 /*
1103 * The 'type' agrees so far, so go ahead and link it in.
1104 * We'll ask again later when we actually connect the hooks.
1105 */
1106 LIST_INSERT_HEAD(&node->nd_hooks, hook, hk_hooks);
1107 node->nd_numhooks++;
1108 NG_HOOK_REF(hook); /* one for the node */
1109
1110 if (hookp)
1111 *hookp = hook;
1112 return (0);
1113 }
1114
1115 /*
1116 * Find a hook
1117 *
1118 * Node types may supply their own optimized routines for finding
1119 * hooks. If none is supplied, we just do a linear search.
1120 * XXX Possibly we should add a reference to the hook?
1121 */
1122 hook_p
1123 ng_findhook(node_p node, const char *name)
1124 {
1125 hook_p hook;
1126
1127 if (node->nd_type->findhook != NULL)
1128 return (*node->nd_type->findhook)(node, name);
1129 LIST_FOREACH(hook, &node->nd_hooks, hk_hooks) {
1130 if (NG_HOOK_IS_VALID(hook) &&
1131 (strcmp(NG_HOOK_NAME(hook), name) == 0))
1132 return (hook);
1133 }
1134 return (NULL);
1135 }
1136
1137 /*
1138 * Destroy a hook
1139 *
1140 * As hooks are always attached, this really destroys two hooks.
1141 * The one given, and the one attached to it. Disconnect the hooks
1142 * from each other first. We reconnect the peer hook to the 'dead'
1143 * hook so that it can still exist after we depart. We then
1144 * send the peer its own destroy message. This ensures that we only
1145 * interact with the peer's structures when it is locked processing that
1146 * message. We hold a reference to the peer hook so we are guaranteed that
1147 * the peer hook and node are still going to exist until
1148 * we are finished there as the hook holds a ref on the node.
1149 * We run this same code again on the peer hook, but that time it is already
1150 * attached to the 'dead' hook.
1151 *
1152 * This routine is called at all stages of hook creation
1153 * on error detection and must be able to handle any such stage.
1154 */
1155 void
1156 ng_destroy_hook(hook_p hook)
1157 {
1158 hook_p peer;
1159 node_p node;
1160
1161 if (hook == &ng_deadhook) { /* better safe than sorry */
1162 printf("ng_destroy_hook called on deadhook\n");
1163 return;
1164 }
1165
1166 /*
1167 * Protect divorce process with mutex, to avoid races on
1168 * simultaneous disconnect.
1169 */
1170 TOPOLOGY_WLOCK();
1171
1172 hook->hk_flags |= HK_INVALID;
1173
1174 peer = NG_HOOK_PEER(hook);
1175 node = NG_HOOK_NODE(hook);
1176
1177 if (peer && (peer != &ng_deadhook)) {
1178 /*
1179 * Set the peer to point to ng_deadhook
1180 * from this moment on we are effectively independent it.
1181 * send it an rmhook message of it's own.
1182 */
1183 peer->hk_peer = &ng_deadhook; /* They no longer know us */
1184 hook->hk_peer = &ng_deadhook; /* Nor us, them */
1185 if (NG_HOOK_NODE(peer) == &ng_deadnode) {
1186 /*
1187 * If it's already divorced from a node,
1188 * just free it.
1189 */
1190 TOPOLOGY_WUNLOCK();
1191 } else {
1192 TOPOLOGY_WUNLOCK();
1193 ng_rmhook_self(peer); /* Send it a surprise */
1194 }
1195 NG_HOOK_UNREF(peer); /* account for peer link */
1196 NG_HOOK_UNREF(hook); /* account for peer link */
1197 } else
1198 TOPOLOGY_WUNLOCK();
1199
1200 TOPOLOGY_NOTOWNED();
1201
1202 /*
1203 * Remove the hook from the node's list to avoid possible recursion
1204 * in case the disconnection results in node shutdown.
1205 */
1206 if (node == &ng_deadnode) { /* happens if called from ng_con_nodes() */
1207 return;
1208 }
1209 LIST_REMOVE(hook, hk_hooks);
1210 node->nd_numhooks--;
1211 if (node->nd_type->disconnect) {
1212 /*
1213 * The type handler may elect to destroy the node so don't
1214 * trust its existence after this point. (except
1215 * that we still hold a reference on it. (which we
1216 * inherrited from the hook we are destroying)
1217 */
1218 (*node->nd_type->disconnect) (hook);
1219 }
1220
1221 /*
1222 * Note that because we will point to ng_deadnode, the original node
1223 * is not decremented automatically so we do that manually.
1224 */
1225 _NG_HOOK_NODE(hook) = &ng_deadnode;
1226 NG_NODE_UNREF(node); /* We no longer point to it so adjust count */
1227 NG_HOOK_UNREF(hook); /* Account for linkage (in list) to node */
1228 }
1229
1230 /*
1231 * Take two hooks on a node and merge the connection so that the given node
1232 * is effectively bypassed.
1233 */
1234 int
1235 ng_bypass(hook_p hook1, hook_p hook2)
1236 {
1237 if (hook1->hk_node != hook2->hk_node) {
1238 TRAP_ERROR();
1239 return (EINVAL);
1240 }
1241 TOPOLOGY_WLOCK();
1242 if (NG_HOOK_NOT_VALID(hook1) || NG_HOOK_NOT_VALID(hook2)) {
1243 TOPOLOGY_WUNLOCK();
1244 return (EINVAL);
1245 }
1246 hook1->hk_peer->hk_peer = hook2->hk_peer;
1247 hook2->hk_peer->hk_peer = hook1->hk_peer;
1248
1249 hook1->hk_peer = &ng_deadhook;
1250 hook2->hk_peer = &ng_deadhook;
1251 TOPOLOGY_WUNLOCK();
1252
1253 NG_HOOK_UNREF(hook1);
1254 NG_HOOK_UNREF(hook2);
1255
1256 /* XXX If we ever cache methods on hooks update them as well */
1257 ng_destroy_hook(hook1);
1258 ng_destroy_hook(hook2);
1259 return (0);
1260 }
1261
1262 /*
1263 * Install a new netgraph type
1264 */
1265 int
1266 ng_newtype(struct ng_type *tp)
1267 {
1268 const size_t namelen = strlen(tp->name);
1269
1270 /* Check version and type name fields */
1271 if ((tp->version != NG_ABI_VERSION) || (namelen == 0) ||
1272 (namelen >= NG_TYPESIZ)) {
1273 TRAP_ERROR();
1274 if (tp->version != NG_ABI_VERSION) {
1275 printf("Netgraph: Node type rejected. ABI mismatch. "
1276 "Suggest recompile\n");
1277 }
1278 return (EINVAL);
1279 }
1280
1281 /* Check for name collision */
1282 if (ng_findtype(tp->name) != NULL) {
1283 TRAP_ERROR();
1284 return (EEXIST);
1285 }
1286
1287 /* Link in new type */
1288 TYPELIST_WLOCK();
1289 LIST_INSERT_HEAD(&ng_typelist, tp, types);
1290 tp->refs = 1; /* first ref is linked list */
1291 TYPELIST_WUNLOCK();
1292 return (0);
1293 }
1294
1295 /*
1296 * unlink a netgraph type
1297 * If no examples exist
1298 */
1299 int
1300 ng_rmtype(struct ng_type *tp)
1301 {
1302 /* Check for name collision */
1303 if (tp->refs != 1) {
1304 TRAP_ERROR();
1305 return (EBUSY);
1306 }
1307
1308 /* Unlink type */
1309 TYPELIST_WLOCK();
1310 LIST_REMOVE(tp, types);
1311 TYPELIST_WUNLOCK();
1312 return (0);
1313 }
1314
1315 /*
1316 * Look for a type of the name given
1317 */
1318 struct ng_type *
1319 ng_findtype(const char *typename)
1320 {
1321 struct ng_type *type;
1322
1323 TYPELIST_RLOCK();
1324 LIST_FOREACH(type, &ng_typelist, types) {
1325 if (strcmp(type->name, typename) == 0)
1326 break;
1327 }
1328 TYPELIST_RUNLOCK();
1329 return (type);
1330 }
1331
1332 /************************************************************************
1333 Composite routines
1334 ************************************************************************/
1335 /*
1336 * Connect two nodes using the specified hooks, using queued functions.
1337 */
1338 static int
1339 ng_con_part3(node_p node, item_p item, hook_p hook)
1340 {
1341 int error = 0;
1342
1343 /*
1344 * When we run, we know that the node 'node' is locked for us.
1345 * Our caller has a reference on the hook.
1346 * Our caller has a reference on the node.
1347 * (In this case our caller is ng_apply_item() ).
1348 * The peer hook has a reference on the hook.
1349 * We are all set up except for the final call to the node, and
1350 * the clearing of the INVALID flag.
1351 */
1352 if (NG_HOOK_NODE(hook) == &ng_deadnode) {
1353 /*
1354 * The node must have been freed again since we last visited
1355 * here. ng_destry_hook() has this effect but nothing else does.
1356 * We should just release our references and
1357 * free anything we can think of.
1358 * Since we know it's been destroyed, and it's our caller
1359 * that holds the references, just return.
1360 */
1361 ERROUT(ENOENT);
1362 }
1363 if (hook->hk_node->nd_type->connect) {
1364 if ((error = (*hook->hk_node->nd_type->connect) (hook))) {
1365 ng_destroy_hook(hook); /* also zaps peer */
1366 printf("failed in ng_con_part3()\n");
1367 ERROUT(error);
1368 }
1369 }
1370 /*
1371 * XXX this is wrong for SMP. Possibly we need
1372 * to separate out 'create' and 'invalid' flags.
1373 * should only set flags on hooks we have locked under our node.
1374 */
1375 hook->hk_flags &= ~HK_INVALID;
1376 done:
1377 NG_FREE_ITEM(item);
1378 return (error);
1379 }
1380
1381 static int
1382 ng_con_part2(node_p node, item_p item, hook_p hook)
1383 {
1384 hook_p peer;
1385 int error = 0;
1386
1387 /*
1388 * When we run, we know that the node 'node' is locked for us.
1389 * Our caller has a reference on the hook.
1390 * Our caller has a reference on the node.
1391 * (In this case our caller is ng_apply_item() ).
1392 * The peer hook has a reference on the hook.
1393 * our node pointer points to the 'dead' node.
1394 * First check the hook name is unique.
1395 * Should not happen because we checked before queueing this.
1396 */
1397 if (ng_findhook(node, NG_HOOK_NAME(hook)) != NULL) {
1398 TRAP_ERROR();
1399 ng_destroy_hook(hook); /* should destroy peer too */
1400 printf("failed in ng_con_part2()\n");
1401 ERROUT(EEXIST);
1402 }
1403 /*
1404 * Check if the node type code has something to say about it
1405 * If it fails, the unref of the hook will also unref the attached node,
1406 * however since that node is 'ng_deadnode' this will do nothing.
1407 * The peer hook will also be destroyed.
1408 */
1409 if (node->nd_type->newhook != NULL) {
1410 if ((error = (*node->nd_type->newhook)(node, hook,
1411 hook->hk_name))) {
1412 ng_destroy_hook(hook); /* should destroy peer too */
1413 printf("failed in ng_con_part2()\n");
1414 ERROUT(error);
1415 }
1416 }
1417
1418 /*
1419 * The 'type' agrees so far, so go ahead and link it in.
1420 * We'll ask again later when we actually connect the hooks.
1421 */
1422 hook->hk_node = node; /* just overwrite ng_deadnode */
1423 NG_NODE_REF(node); /* each hook counts as a reference */
1424 LIST_INSERT_HEAD(&node->nd_hooks, hook, hk_hooks);
1425 node->nd_numhooks++;
1426 NG_HOOK_REF(hook); /* one for the node */
1427
1428 /*
1429 * We now have a symmetrical situation, where both hooks have been
1430 * linked to their nodes, the newhook methods have been called
1431 * And the references are all correct. The hooks are still marked
1432 * as invalid, as we have not called the 'connect' methods
1433 * yet.
1434 * We can call the local one immediately as we have the
1435 * node locked, but we need to queue the remote one.
1436 */
1437 if (hook->hk_node->nd_type->connect) {
1438 if ((error = (*hook->hk_node->nd_type->connect) (hook))) {
1439 ng_destroy_hook(hook); /* also zaps peer */
1440 printf("failed in ng_con_part2(A)\n");
1441 ERROUT(error);
1442 }
1443 }
1444
1445 /*
1446 * Acquire topo mutex to avoid race with ng_destroy_hook().
1447 */
1448 TOPOLOGY_RLOCK();
1449 peer = hook->hk_peer;
1450 if (peer == &ng_deadhook) {
1451 TOPOLOGY_RUNLOCK();
1452 printf("failed in ng_con_part2(B)\n");
1453 ng_destroy_hook(hook);
1454 ERROUT(ENOENT);
1455 }
1456 TOPOLOGY_RUNLOCK();
1457
1458 if ((error = ng_send_fn2(peer->hk_node, peer, item, &ng_con_part3,
1459 NULL, 0, NG_REUSE_ITEM))) {
1460 printf("failed in ng_con_part2(C)\n");
1461 ng_destroy_hook(hook); /* also zaps peer */
1462 return (error); /* item was consumed. */
1463 }
1464 hook->hk_flags &= ~HK_INVALID; /* need both to be able to work */
1465 return (0); /* item was consumed. */
1466 done:
1467 NG_FREE_ITEM(item);
1468 return (error);
1469 }
1470
1471 /*
1472 * Connect this node with another node. We assume that this node is
1473 * currently locked, as we are only called from an NGM_CONNECT message.
1474 */
1475 static int
1476 ng_con_nodes(item_p item, node_p node, const char *name,
1477 node_p node2, const char *name2)
1478 {
1479 int error;
1480 hook_p hook;
1481 hook_p hook2;
1482
1483 if (ng_findhook(node2, name2) != NULL) {
1484 return(EEXIST);
1485 }
1486 if ((error = ng_add_hook(node, name, &hook))) /* gives us a ref */
1487 return (error);
1488 /* Allocate the other hook and link it up */
1489 NG_ALLOC_HOOK(hook2);
1490 if (hook2 == NULL) {
1491 TRAP_ERROR();
1492 ng_destroy_hook(hook); /* XXX check ref counts so far */
1493 NG_HOOK_UNREF(hook); /* including our ref */
1494 return (ENOMEM);
1495 }
1496 hook2->hk_refs = 1; /* start with a reference for us. */
1497 hook2->hk_flags = HK_INVALID;
1498 hook2->hk_peer = hook; /* Link the two together */
1499 hook->hk_peer = hook2;
1500 NG_HOOK_REF(hook); /* Add a ref for the peer to each*/
1501 NG_HOOK_REF(hook2);
1502 hook2->hk_node = &ng_deadnode;
1503 strlcpy(NG_HOOK_NAME(hook2), name2, NG_HOOKSIZ);
1504
1505 /*
1506 * Queue the function above.
1507 * Procesing continues in that function in the lock context of
1508 * the other node.
1509 */
1510 if ((error = ng_send_fn2(node2, hook2, item, &ng_con_part2, NULL, 0,
1511 NG_NOFLAGS))) {
1512 printf("failed in ng_con_nodes(): %d\n", error);
1513 ng_destroy_hook(hook); /* also zaps peer */
1514 }
1515
1516 NG_HOOK_UNREF(hook); /* Let each hook go if it wants to */
1517 NG_HOOK_UNREF(hook2);
1518 return (error);
1519 }
1520
1521 /*
1522 * Make a peer and connect.
1523 * We assume that the local node is locked.
1524 * The new node probably doesn't need a lock until
1525 * it has a hook, because it cannot really have any work until then,
1526 * but we should think about it a bit more.
1527 *
1528 * The problem may come if the other node also fires up
1529 * some hardware or a timer or some other source of activation,
1530 * also it may already get a command msg via it's ID.
1531 *
1532 * We could use the same method as ng_con_nodes() but we'd have
1533 * to add ability to remove the node when failing. (Not hard, just
1534 * make arg1 point to the node to remove).
1535 * Unless of course we just ignore failure to connect and leave
1536 * an unconnected node?
1537 */
1538 static int
1539 ng_mkpeer(node_p node, const char *name, const char *name2, char *type)
1540 {
1541 node_p node2;
1542 hook_p hook1, hook2;
1543 int error;
1544
1545 if ((error = ng_make_node(type, &node2))) {
1546 return (error);
1547 }
1548
1549 if ((error = ng_add_hook(node, name, &hook1))) { /* gives us a ref */
1550 ng_rmnode(node2, NULL, NULL, 0);
1551 return (error);
1552 }
1553
1554 if ((error = ng_add_hook(node2, name2, &hook2))) {
1555 ng_rmnode(node2, NULL, NULL, 0);
1556 ng_destroy_hook(hook1);
1557 NG_HOOK_UNREF(hook1);
1558 return (error);
1559 }
1560
1561 /*
1562 * Actually link the two hooks together.
1563 */
1564 hook1->hk_peer = hook2;
1565 hook2->hk_peer = hook1;
1566
1567 /* Each hook is referenced by the other */
1568 NG_HOOK_REF(hook1);
1569 NG_HOOK_REF(hook2);
1570
1571 /* Give each node the opportunity to veto the pending connection */
1572 if (hook1->hk_node->nd_type->connect) {
1573 error = (*hook1->hk_node->nd_type->connect) (hook1);
1574 }
1575
1576 if ((error == 0) && hook2->hk_node->nd_type->connect) {
1577 error = (*hook2->hk_node->nd_type->connect) (hook2);
1578
1579 }
1580
1581 /*
1582 * drop the references we were holding on the two hooks.
1583 */
1584 if (error) {
1585 ng_destroy_hook(hook2); /* also zaps hook1 */
1586 ng_rmnode(node2, NULL, NULL, 0);
1587 } else {
1588 /* As a last act, allow the hooks to be used */
1589 hook1->hk_flags &= ~HK_INVALID;
1590 hook2->hk_flags &= ~HK_INVALID;
1591 }
1592 NG_HOOK_UNREF(hook1);
1593 NG_HOOK_UNREF(hook2);
1594 return (error);
1595 }
1596
1597 /************************************************************************
1598 Utility routines to send self messages
1599 ************************************************************************/
1600
1601 /* Shut this node down as soon as everyone is clear of it */
1602 /* Should add arg "immediately" to jump the queue */
1603 int
1604 ng_rmnode_self(node_p node)
1605 {
1606 int error;
1607
1608 if (node == &ng_deadnode)
1609 return (0);
1610 node->nd_flags |= NGF_INVALID;
1611 if (node->nd_flags & NGF_CLOSING)
1612 return (0);
1613
1614 error = ng_send_fn(node, NULL, &ng_rmnode, NULL, 0);
1615 return (error);
1616 }
1617
1618 static void
1619 ng_rmhook_part2(node_p node, hook_p hook, void *arg1, int arg2)
1620 {
1621 ng_destroy_hook(hook);
1622 return ;
1623 }
1624
1625 int
1626 ng_rmhook_self(hook_p hook)
1627 {
1628 int error;
1629 node_p node = NG_HOOK_NODE(hook);
1630
1631 if (node == &ng_deadnode)
1632 return (0);
1633
1634 error = ng_send_fn(node, hook, &ng_rmhook_part2, NULL, 0);
1635 return (error);
1636 }
1637
1638 /***********************************************************************
1639 * Parse and verify a string of the form: <NODE:><PATH>
1640 *
1641 * Such a string can refer to a specific node or a specific hook
1642 * on a specific node, depending on how you look at it. In the
1643 * latter case, the PATH component must not end in a dot.
1644 *
1645 * Both <NODE:> and <PATH> are optional. The <PATH> is a string
1646 * of hook names separated by dots. This breaks out the original
1647 * string, setting *nodep to "NODE" (or NULL if none) and *pathp
1648 * to "PATH" (or NULL if degenerate). Also, *hookp will point to
1649 * the final hook component of <PATH>, if any, otherwise NULL.
1650 *
1651 * This returns -1 if the path is malformed. The char ** are optional.
1652 ***********************************************************************/
1653 int
1654 ng_path_parse(char *addr, char **nodep, char **pathp, char **hookp)
1655 {
1656 char *node, *path, *hook;
1657 int k;
1658
1659 /*
1660 * Extract absolute NODE, if any
1661 */
1662 for (path = addr; *path && *path != ':'; path++);
1663 if (*path) {
1664 node = addr; /* Here's the NODE */
1665 *path++ = '\0'; /* Here's the PATH */
1666
1667 /* Node name must not be empty */
1668 if (!*node)
1669 return -1;
1670
1671 /* A name of "." is OK; otherwise '.' not allowed */
1672 if (strcmp(node, ".") != 0) {
1673 for (k = 0; node[k]; k++)
1674 if (node[k] == '.')
1675 return -1;
1676 }
1677 } else {
1678 node = NULL; /* No absolute NODE */
1679 path = addr; /* Here's the PATH */
1680 }
1681
1682 /* Snoop for illegal characters in PATH */
1683 for (k = 0; path[k]; k++)
1684 if (path[k] == ':')
1685 return -1;
1686
1687 /* Check for no repeated dots in PATH */
1688 for (k = 0; path[k]; k++)
1689 if (path[k] == '.' && path[k + 1] == '.')
1690 return -1;
1691
1692 /* Remove extra (degenerate) dots from beginning or end of PATH */
1693 if (path[0] == '.')
1694 path++;
1695 if (*path && path[strlen(path) - 1] == '.')
1696 path[strlen(path) - 1] = 0;
1697
1698 /* If PATH has a dot, then we're not talking about a hook */
1699 if (*path) {
1700 for (hook = path, k = 0; path[k]; k++)
1701 if (path[k] == '.') {
1702 hook = NULL;
1703 break;
1704 }
1705 } else
1706 path = hook = NULL;
1707
1708 /* Done */
1709 if (nodep)
1710 *nodep = node;
1711 if (pathp)
1712 *pathp = path;
1713 if (hookp)
1714 *hookp = hook;
1715 return (0);
1716 }
1717
1718 /*
1719 * Given a path, which may be absolute or relative, and a starting node,
1720 * return the destination node.
1721 */
1722 int
1723 ng_path2noderef(node_p here, const char *address, node_p *destp,
1724 hook_p *lasthook)
1725 {
1726 char fullpath[NG_PATHSIZ];
1727 char *nodename, *path;
1728 node_p node, oldnode;
1729
1730 /* Initialize */
1731 if (destp == NULL) {
1732 TRAP_ERROR();
1733 return EINVAL;
1734 }
1735 *destp = NULL;
1736
1737 /* Make a writable copy of address for ng_path_parse() */
1738 strncpy(fullpath, address, sizeof(fullpath) - 1);
1739 fullpath[sizeof(fullpath) - 1] = '\0';
1740
1741 /* Parse out node and sequence of hooks */
1742 if (ng_path_parse(fullpath, &nodename, &path, NULL) < 0) {
1743 TRAP_ERROR();
1744 return EINVAL;
1745 }
1746
1747 /*
1748 * For an absolute address, jump to the starting node.
1749 * Note that this holds a reference on the node for us.
1750 * Don't forget to drop the reference if we don't need it.
1751 */
1752 if (nodename) {
1753 node = ng_name2noderef(here, nodename);
1754 if (node == NULL) {
1755 TRAP_ERROR();
1756 return (ENOENT);
1757 }
1758 } else {
1759 if (here == NULL) {
1760 TRAP_ERROR();
1761 return (EINVAL);
1762 }
1763 node = here;
1764 NG_NODE_REF(node);
1765 }
1766
1767 if (path == NULL) {
1768 if (lasthook != NULL)
1769 *lasthook = NULL;
1770 *destp = node;
1771 return (0);
1772 }
1773
1774 /*
1775 * Now follow the sequence of hooks
1776 *
1777 * XXXGL: The path may demolish as we go the sequence, but if
1778 * we hold the topology mutex at critical places, then, I hope,
1779 * we would always have valid pointers in hand, although the
1780 * path behind us may no longer exist.
1781 */
1782 for (;;) {
1783 hook_p hook;
1784 char *segment;
1785
1786 /*
1787 * Break out the next path segment. Replace the dot we just
1788 * found with a NUL; "path" points to the next segment (or the
1789 * NUL at the end).
1790 */
1791 for (segment = path; *path != '\0'; path++) {
1792 if (*path == '.') {
1793 *path++ = '\0';
1794 break;
1795 }
1796 }
1797
1798 /* We have a segment, so look for a hook by that name */
1799 hook = ng_findhook(node, segment);
1800
1801 TOPOLOGY_WLOCK();
1802 /* Can't get there from here... */
1803 if (hook == NULL || NG_HOOK_PEER(hook) == NULL ||
1804 NG_HOOK_NOT_VALID(hook) ||
1805 NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook))) {
1806 TRAP_ERROR();
1807 NG_NODE_UNREF(node);
1808 TOPOLOGY_WUNLOCK();
1809 return (ENOENT);
1810 }
1811
1812 /*
1813 * Hop on over to the next node
1814 * XXX
1815 * Big race conditions here as hooks and nodes go away
1816 * *** Idea.. store an ng_ID_t in each hook and use that
1817 * instead of the direct hook in this crawl?
1818 */
1819 oldnode = node;
1820 if ((node = NG_PEER_NODE(hook)))
1821 NG_NODE_REF(node); /* XXX RACE */
1822 NG_NODE_UNREF(oldnode); /* XXX another race */
1823 if (NG_NODE_NOT_VALID(node)) {
1824 NG_NODE_UNREF(node); /* XXX more races */
1825 TOPOLOGY_WUNLOCK();
1826 TRAP_ERROR();
1827 return (ENXIO);
1828 }
1829
1830 if (*path == '\0') {
1831 if (lasthook != NULL) {
1832 if (hook != NULL) {
1833 *lasthook = NG_HOOK_PEER(hook);
1834 NG_HOOK_REF(*lasthook);
1835 } else
1836 *lasthook = NULL;
1837 }
1838 TOPOLOGY_WUNLOCK();
1839 *destp = node;
1840 return (0);
1841 }
1842 TOPOLOGY_WUNLOCK();
1843 }
1844 }
1845
1846 /***************************************************************\
1847 * Input queue handling.
1848 * All activities are submitted to the node via the input queue
1849 * which implements a multiple-reader/single-writer gate.
1850 * Items which cannot be handled immediately are queued.
1851 *
1852 * read-write queue locking inline functions *
1853 \***************************************************************/
1854
1855 static __inline void ng_queue_rw(node_p node, item_p item, int rw);
1856 static __inline item_p ng_dequeue(node_p node, int *rw);
1857 static __inline item_p ng_acquire_read(node_p node, item_p item);
1858 static __inline item_p ng_acquire_write(node_p node, item_p item);
1859 static __inline void ng_leave_read(node_p node);
1860 static __inline void ng_leave_write(node_p node);
1861
1862 /*
1863 * Definition of the bits fields in the ng_queue flag word.
1864 * Defined here rather than in netgraph.h because no-one should fiddle
1865 * with them.
1866 *
1867 * The ordering here may be important! don't shuffle these.
1868 */
1869 /*-
1870 Safety Barrier--------+ (adjustable to suit taste) (not used yet)
1871 |
1872 V
1873 +-------+-------+-------+-------+-------+-------+-------+-------+
1874 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
1875 | |A|c|t|i|v|e| |R|e|a|d|e|r| |C|o|u|n|t| | | | | | | | | |P|A|
1876 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |O|W|
1877 +-------+-------+-------+-------+-------+-------+-------+-------+
1878 \___________________________ ____________________________/ | |
1879 V | |
1880 [active reader count] | |
1881 | |
1882 Operation Pending -------------------------------+ |
1883 |
1884 Active Writer ---------------------------------------+
1885
1886 Node queue has such semantics:
1887 - All flags modifications are atomic.
1888 - Reader count can be incremented only if there is no writer or pending flags.
1889 As soon as this can't be done with single operation, it is implemented with
1890 spin loop and atomic_cmpset().
1891 - Writer flag can be set only if there is no any bits set.
1892 It is implemented with atomic_cmpset().
1893 - Pending flag can be set any time, but to avoid collision on queue processing
1894 all queue fields are protected by the mutex.
1895 - Queue processing thread reads queue holding the mutex, but releases it while
1896 processing. When queue is empty pending flag is removed.
1897 */
1898
1899 #define WRITER_ACTIVE 0x00000001
1900 #define OP_PENDING 0x00000002
1901 #define READER_INCREMENT 0x00000004
1902 #define READER_MASK 0xfffffffc /* Not valid if WRITER_ACTIVE is set */
1903 #define SAFETY_BARRIER 0x00100000 /* 128K items queued should be enough */
1904
1905 /* Defines of more elaborate states on the queue */
1906 /* Mask of bits a new read cares about */
1907 #define NGQ_RMASK (WRITER_ACTIVE|OP_PENDING)
1908
1909 /* Mask of bits a new write cares about */
1910 #define NGQ_WMASK (NGQ_RMASK|READER_MASK)
1911
1912 /* Test to decide if there is something on the queue. */
1913 #define QUEUE_ACTIVE(QP) ((QP)->q_flags & OP_PENDING)
1914
1915 /* How to decide what the next queued item is. */
1916 #define HEAD_IS_READER(QP) NGI_QUEUED_READER(STAILQ_FIRST(&(QP)->queue))
1917 #define HEAD_IS_WRITER(QP) NGI_QUEUED_WRITER(STAILQ_FIRST(&(QP)->queue)) /* notused */
1918
1919 /* Read the status to decide if the next item on the queue can now run. */
1920 #define QUEUED_READER_CAN_PROCEED(QP) \
1921 (((QP)->q_flags & (NGQ_RMASK & ~OP_PENDING)) == 0)
1922 #define QUEUED_WRITER_CAN_PROCEED(QP) \
1923 (((QP)->q_flags & (NGQ_WMASK & ~OP_PENDING)) == 0)
1924
1925 /* Is there a chance of getting ANY work off the queue? */
1926 #define NEXT_QUEUED_ITEM_CAN_PROCEED(QP) \
1927 ((HEAD_IS_READER(QP)) ? QUEUED_READER_CAN_PROCEED(QP) : \
1928 QUEUED_WRITER_CAN_PROCEED(QP))
1929
1930 #define NGQRW_R 0
1931 #define NGQRW_W 1
1932
1933 #define NGQ2_WORKQ 0x00000001
1934
1935 /*
1936 * Taking into account the current state of the queue and node, possibly take
1937 * the next entry off the queue and return it. Return NULL if there was
1938 * nothing we could return, either because there really was nothing there, or
1939 * because the node was in a state where it cannot yet process the next item
1940 * on the queue.
1941 */
1942 static __inline item_p
1943 ng_dequeue(node_p node, int *rw)
1944 {
1945 item_p item;
1946 struct ng_queue *ngq = &node->nd_input_queue;
1947
1948 /* This MUST be called with the mutex held. */
1949 mtx_assert(&ngq->q_mtx, MA_OWNED);
1950
1951 /* If there is nothing queued, then just return. */
1952 if (!QUEUE_ACTIVE(ngq)) {
1953 CTR4(KTR_NET, "%20s: node [%x] (%p) queue empty; "
1954 "queue flags 0x%lx", __func__,
1955 node->nd_ID, node, ngq->q_flags);
1956 return (NULL);
1957 }
1958
1959 /*
1960 * From here, we can assume there is a head item.
1961 * We need to find out what it is and if it can be dequeued, given
1962 * the current state of the node.
1963 */
1964 if (HEAD_IS_READER(ngq)) {
1965 while (1) {
1966 long t = ngq->q_flags;
1967 if (t & WRITER_ACTIVE) {
1968 /* There is writer, reader can't proceed. */
1969 CTR4(KTR_NET, "%20s: node [%x] (%p) queued "
1970 "reader can't proceed; queue flags 0x%lx",
1971 __func__, node->nd_ID, node, t);
1972 return (NULL);
1973 }
1974 if (atomic_cmpset_acq_int(&ngq->q_flags, t,
1975 t + READER_INCREMENT))
1976 break;
1977 cpu_spinwait();
1978 }
1979 /* We have got reader lock for the node. */
1980 *rw = NGQRW_R;
1981 } else if (atomic_cmpset_acq_int(&ngq->q_flags, OP_PENDING,
1982 OP_PENDING + WRITER_ACTIVE)) {
1983 /* We have got writer lock for the node. */
1984 *rw = NGQRW_W;
1985 } else {
1986 /* There is somebody other, writer can't proceed. */
1987 CTR4(KTR_NET, "%20s: node [%x] (%p) queued writer can't "
1988 "proceed; queue flags 0x%lx", __func__, node->nd_ID, node,
1989 ngq->q_flags);
1990 return (NULL);
1991 }
1992
1993 /*
1994 * Now we dequeue the request (whatever it may be) and correct the
1995 * pending flags and the next and last pointers.
1996 */
1997 item = STAILQ_FIRST(&ngq->queue);
1998 STAILQ_REMOVE_HEAD(&ngq->queue, el_next);
1999 if (STAILQ_EMPTY(&ngq->queue))
2000 atomic_clear_int(&ngq->q_flags, OP_PENDING);
2001 CTR6(KTR_NET, "%20s: node [%x] (%p) returning item %p as %s; queue "
2002 "flags 0x%lx", __func__, node->nd_ID, node, item, *rw ? "WRITER" :
2003 "READER", ngq->q_flags);
2004 return (item);
2005 }
2006
2007 /*
2008 * Queue a packet to be picked up later by someone else.
2009 * If the queue could be run now, add node to the queue handler's worklist.
2010 */
2011 static __inline void
2012 ng_queue_rw(node_p node, item_p item, int rw)
2013 {
2014 struct ng_queue *ngq = &node->nd_input_queue;
2015 if (rw == NGQRW_W)
2016 NGI_SET_WRITER(item);
2017 else
2018 NGI_SET_READER(item);
2019 item->depth = 1;
2020
2021 NG_QUEUE_LOCK(ngq);
2022 /* Set OP_PENDING flag and enqueue the item. */
2023 atomic_set_int(&ngq->q_flags, OP_PENDING);
2024 STAILQ_INSERT_TAIL(&ngq->queue, item, el_next);
2025
2026 CTR5(KTR_NET, "%20s: node [%x] (%p) queued item %p as %s", __func__,
2027 node->nd_ID, node, item, rw ? "WRITER" : "READER" );
2028
2029 /*
2030 * We can take the worklist lock with the node locked
2031 * BUT NOT THE REVERSE!
2032 */
2033 if (NEXT_QUEUED_ITEM_CAN_PROCEED(ngq))
2034 ng_worklist_add(node);
2035 NG_QUEUE_UNLOCK(ngq);
2036 }
2037
2038 /* Acquire reader lock on node. If node is busy, queue the packet. */
2039 static __inline item_p
2040 ng_acquire_read(node_p node, item_p item)
2041 {
2042 KASSERT(node != &ng_deadnode,
2043 ("%s: working on deadnode", __func__));
2044
2045 /* Reader needs node without writer and pending items. */
2046 for (;;) {
2047 long t = node->nd_input_queue.q_flags;
2048 if (t & NGQ_RMASK)
2049 break; /* Node is not ready for reader. */
2050 if (atomic_cmpset_acq_int(&node->nd_input_queue.q_flags, t,
2051 t + READER_INCREMENT)) {
2052 /* Successfully grabbed node */
2053 CTR4(KTR_NET, "%20s: node [%x] (%p) acquired item %p",
2054 __func__, node->nd_ID, node, item);
2055 return (item);
2056 }
2057 cpu_spinwait();
2058 };
2059
2060 /* Queue the request for later. */
2061 ng_queue_rw(node, item, NGQRW_R);
2062
2063 return (NULL);
2064 }
2065
2066 /* Acquire writer lock on node. If node is busy, queue the packet. */
2067 static __inline item_p
2068 ng_acquire_write(node_p node, item_p item)
2069 {
2070 KASSERT(node != &ng_deadnode,
2071 ("%s: working on deadnode", __func__));
2072
2073 /* Writer needs completely idle node. */
2074 if (atomic_cmpset_acq_int(&node->nd_input_queue.q_flags, 0,
2075 WRITER_ACTIVE)) {
2076 /* Successfully grabbed node */
2077 CTR4(KTR_NET, "%20s: node [%x] (%p) acquired item %p",
2078 __func__, node->nd_ID, node, item);
2079 return (item);
2080 }
2081
2082 /* Queue the request for later. */
2083 ng_queue_rw(node, item, NGQRW_W);
2084
2085 return (NULL);
2086 }
2087
2088 #if 0
2089 static __inline item_p
2090 ng_upgrade_write(node_p node, item_p item)
2091 {
2092 struct ng_queue *ngq = &node->nd_input_queue;
2093 KASSERT(node != &ng_deadnode,
2094 ("%s: working on deadnode", __func__));
2095
2096 NGI_SET_WRITER(item);
2097
2098 NG_QUEUE_LOCK(ngq);
2099
2100 /*
2101 * There will never be no readers as we are there ourselves.
2102 * Set the WRITER_ACTIVE flags ASAP to block out fast track readers.
2103 * The caller we are running from will call ng_leave_read()
2104 * soon, so we must account for that. We must leave again with the
2105 * READER lock. If we find other readers, then
2106 * queue the request for later. However "later" may be rignt now
2107 * if there are no readers. We don't really care if there are queued
2108 * items as we will bypass them anyhow.
2109 */
2110 atomic_add_int(&ngq->q_flags, WRITER_ACTIVE - READER_INCREMENT);
2111 if ((ngq->q_flags & (NGQ_WMASK & ~OP_PENDING)) == WRITER_ACTIVE) {
2112 NG_QUEUE_UNLOCK(ngq);
2113
2114 /* It's just us, act on the item. */
2115 /* will NOT drop writer lock when done */
2116 ng_apply_item(node, item, 0);
2117
2118 /*
2119 * Having acted on the item, atomically
2120 * downgrade back to READER and finish up.
2121 */
2122 atomic_add_int(&ngq->q_flags, READER_INCREMENT - WRITER_ACTIVE);
2123
2124 /* Our caller will call ng_leave_read() */
2125 return;
2126 }
2127 /*
2128 * It's not just us active, so queue us AT THE HEAD.
2129 * "Why?" I hear you ask.
2130 * Put us at the head of the queue as we've already been
2131 * through it once. If there is nothing else waiting,
2132 * set the correct flags.
2133 */
2134 if (STAILQ_EMPTY(&ngq->queue)) {
2135 /* We've gone from, 0 to 1 item in the queue */
2136 atomic_set_int(&ngq->q_flags, OP_PENDING);
2137
2138 CTR3(KTR_NET, "%20s: node [%x] (%p) set OP_PENDING", __func__,
2139 node->nd_ID, node);
2140 };
2141 STAILQ_INSERT_HEAD(&ngq->queue, item, el_next);
2142 CTR4(KTR_NET, "%20s: node [%x] (%p) requeued item %p as WRITER",
2143 __func__, node->nd_ID, node, item );
2144
2145 /* Reverse what we did above. That downgrades us back to reader */
2146 atomic_add_int(&ngq->q_flags, READER_INCREMENT - WRITER_ACTIVE);
2147 if (QUEUE_ACTIVE(ngq) && NEXT_QUEUED_ITEM_CAN_PROCEED(ngq))
2148 ng_worklist_add(node);
2149 NG_QUEUE_UNLOCK(ngq);
2150
2151 return;
2152 }
2153 #endif
2154
2155 /* Release reader lock. */
2156 static __inline void
2157 ng_leave_read(node_p node)
2158 {
2159 atomic_subtract_rel_int(&node->nd_input_queue.q_flags, READER_INCREMENT);
2160 }
2161
2162 /* Release writer lock. */
2163 static __inline void
2164 ng_leave_write(node_p node)
2165 {
2166 atomic_clear_rel_int(&node->nd_input_queue.q_flags, WRITER_ACTIVE);
2167 }
2168
2169 /* Purge node queue. Called on node shutdown. */
2170 static void
2171 ng_flush_input_queue(node_p node)
2172 {
2173 struct ng_queue *ngq = &node->nd_input_queue;
2174 item_p item;
2175
2176 NG_QUEUE_LOCK(ngq);
2177 while ((item = STAILQ_FIRST(&ngq->queue)) != NULL) {
2178 STAILQ_REMOVE_HEAD(&ngq->queue, el_next);
2179 if (STAILQ_EMPTY(&ngq->queue))
2180 atomic_clear_int(&ngq->q_flags, OP_PENDING);
2181 NG_QUEUE_UNLOCK(ngq);
2182
2183 /* If the item is supplying a callback, call it with an error */
2184 if (item->apply != NULL) {
2185 if (item->depth == 1)
2186 item->apply->error = ENOENT;
2187 if (refcount_release(&item->apply->refs)) {
2188 (*item->apply->apply)(item->apply->context,
2189 item->apply->error);
2190 }
2191 }
2192 NG_FREE_ITEM(item);
2193 NG_QUEUE_LOCK(ngq);
2194 }
2195 NG_QUEUE_UNLOCK(ngq);
2196 }
2197
2198 /***********************************************************************
2199 * Externally visible method for sending or queueing messages or data.
2200 ***********************************************************************/
2201
2202 /*
2203 * The module code should have filled out the item correctly by this stage:
2204 * Common:
2205 * reference to destination node.
2206 * Reference to destination rcv hook if relevant.
2207 * apply pointer must be or NULL or reference valid struct ng_apply_info.
2208 * Data:
2209 * pointer to mbuf
2210 * Control_Message:
2211 * pointer to msg.
2212 * ID of original sender node. (return address)
2213 * Function:
2214 * Function pointer
2215 * void * argument
2216 * integer argument
2217 *
2218 * The nodes have several routines and macros to help with this task:
2219 */
2220
2221 int
2222 ng_snd_item(item_p item, int flags)
2223 {
2224 hook_p hook;
2225 node_p node;
2226 int queue, rw;
2227 struct ng_queue *ngq;
2228 int error = 0;
2229
2230 /* We are sending item, so it must be present! */
2231 KASSERT(item != NULL, ("ng_snd_item: item is NULL"));
2232
2233 #ifdef NETGRAPH_DEBUG
2234 _ngi_check(item, __FILE__, __LINE__);
2235 #endif
2236
2237 /* Item was sent once more, postpone apply() call. */
2238 if (item->apply)
2239 refcount_acquire(&item->apply->refs);
2240
2241 node = NGI_NODE(item);
2242 /* Node is never optional. */
2243 KASSERT(node != NULL, ("ng_snd_item: node is NULL"));
2244
2245 hook = NGI_HOOK(item);
2246 /* Valid hook and mbuf are mandatory for data. */
2247 if ((item->el_flags & NGQF_TYPE) == NGQF_DATA) {
2248 KASSERT(hook != NULL, ("ng_snd_item: hook for data is NULL"));
2249 if (NGI_M(item) == NULL)
2250 ERROUT(EINVAL);
2251 CHECK_DATA_MBUF(NGI_M(item));
2252 }
2253
2254 /*
2255 * If the item or the node specifies single threading, force
2256 * writer semantics. Similarly, the node may say one hook always
2257 * produces writers. These are overrides.
2258 */
2259 if (((item->el_flags & NGQF_RW) == NGQF_WRITER) ||
2260 (node->nd_flags & NGF_FORCE_WRITER) ||
2261 (hook && (hook->hk_flags & HK_FORCE_WRITER))) {
2262 rw = NGQRW_W;
2263 } else {
2264 rw = NGQRW_R;
2265 }
2266
2267 /*
2268 * If sender or receiver requests queued delivery, or call graph
2269 * loops back from outbound to inbound path, or stack usage
2270 * level is dangerous - enqueue message.
2271 */
2272 if ((flags & NG_QUEUE) || (hook && (hook->hk_flags & HK_QUEUE))) {
2273 queue = 1;
2274 } else if (hook && (hook->hk_flags & HK_TO_INBOUND) &&
2275 curthread->td_ng_outbound) {
2276 queue = 1;
2277 } else {
2278 queue = 0;
2279 #ifdef GET_STACK_USAGE
2280 /*
2281 * Most of netgraph nodes have small stack consumption and
2282 * for them 25% of free stack space is more than enough.
2283 * Nodes/hooks with higher stack usage should be marked as
2284 * HI_STACK. For them 50% of stack will be guaranteed then.
2285 * XXX: Values 25% and 50% are completely empirical.
2286 */
2287 size_t st, su, sl;
2288 GET_STACK_USAGE(st, su);
2289 sl = st - su;
2290 if ((sl * 4 < st) || ((sl * 2 < st) &&
2291 ((node->nd_flags & NGF_HI_STACK) || (hook &&
2292 (hook->hk_flags & HK_HI_STACK)))))
2293 queue = 1;
2294 #endif
2295 }
2296
2297 if (queue) {
2298 /* Put it on the queue for that node*/
2299 ng_queue_rw(node, item, rw);
2300 return ((flags & NG_PROGRESS) ? EINPROGRESS : 0);
2301 }
2302
2303 /*
2304 * We already decided how we will be queueud or treated.
2305 * Try get the appropriate operating permission.
2306 */
2307 if (rw == NGQRW_R)
2308 item = ng_acquire_read(node, item);
2309 else
2310 item = ng_acquire_write(node, item);
2311
2312 /* Item was queued while trying to get permission. */
2313 if (item == NULL)
2314 return ((flags & NG_PROGRESS) ? EINPROGRESS : 0);
2315
2316 NGI_GET_NODE(item, node); /* zaps stored node */
2317
2318 item->depth++;
2319 error = ng_apply_item(node, item, rw); /* drops r/w lock when done */
2320
2321 /* If something is waiting on queue and ready, schedule it. */
2322 ngq = &node->nd_input_queue;
2323 if (QUEUE_ACTIVE(ngq)) {
2324 NG_QUEUE_LOCK(ngq);
2325 if (QUEUE_ACTIVE(ngq) && NEXT_QUEUED_ITEM_CAN_PROCEED(ngq))
2326 ng_worklist_add(node);
2327 NG_QUEUE_UNLOCK(ngq);
2328 }
2329
2330 /*
2331 * Node may go away as soon as we remove the reference.
2332 * Whatever we do, DO NOT access the node again!
2333 */
2334 NG_NODE_UNREF(node);
2335
2336 return (error);
2337
2338 done:
2339 /* If was not sent, apply callback here. */
2340 if (item->apply != NULL) {
2341 if (item->depth == 0 && error != 0)
2342 item->apply->error = error;
2343 if (refcount_release(&item->apply->refs)) {
2344 (*item->apply->apply)(item->apply->context,
2345 item->apply->error);
2346 }
2347 }
2348
2349 NG_FREE_ITEM(item);
2350 return (error);
2351 }
2352
2353 /*
2354 * We have an item that was possibly queued somewhere.
2355 * It should contain all the information needed
2356 * to run it on the appropriate node/hook.
2357 * If there is apply pointer and we own the last reference, call apply().
2358 */
2359 static int
2360 ng_apply_item(node_p node, item_p item, int rw)
2361 {
2362 hook_p hook;
2363 ng_rcvdata_t *rcvdata;
2364 ng_rcvmsg_t *rcvmsg;
2365 struct ng_apply_info *apply;
2366 int error = 0, depth;
2367
2368 /* Node and item are never optional. */
2369 KASSERT(node != NULL, ("ng_apply_item: node is NULL"));
2370 KASSERT(item != NULL, ("ng_apply_item: item is NULL"));
2371
2372 NGI_GET_HOOK(item, hook); /* clears stored hook */
2373 #ifdef NETGRAPH_DEBUG
2374 _ngi_check(item, __FILE__, __LINE__);
2375 #endif
2376
2377 apply = item->apply;
2378 depth = item->depth;
2379
2380 switch (item->el_flags & NGQF_TYPE) {
2381 case NGQF_DATA:
2382 /*
2383 * Check things are still ok as when we were queued.
2384 */
2385 KASSERT(hook != NULL, ("ng_apply_item: hook for data is NULL"));
2386 if (NG_HOOK_NOT_VALID(hook) ||
2387 NG_NODE_NOT_VALID(node)) {
2388 error = EIO;
2389 NG_FREE_ITEM(item);
2390 break;
2391 }
2392 /*
2393 * If no receive method, just silently drop it.
2394 * Give preference to the hook over-ride method.
2395 */
2396 if ((!(rcvdata = hook->hk_rcvdata)) &&
2397 (!(rcvdata = NG_HOOK_NODE(hook)->nd_type->rcvdata))) {
2398 error = 0;
2399 NG_FREE_ITEM(item);
2400 break;
2401 }
2402 error = (*rcvdata)(hook, item);
2403 break;
2404 case NGQF_MESG:
2405 if (hook && NG_HOOK_NOT_VALID(hook)) {
2406 /*
2407 * The hook has been zapped then we can't use it.
2408 * Immediately drop its reference.
2409 * The message may not need it.
2410 */
2411 NG_HOOK_UNREF(hook);
2412 hook = NULL;
2413 }
2414 /*
2415 * Similarly, if the node is a zombie there is
2416 * nothing we can do with it, drop everything.
2417 */
2418 if (NG_NODE_NOT_VALID(node)) {
2419 TRAP_ERROR();
2420 error = EINVAL;
2421 NG_FREE_ITEM(item);
2422 break;
2423 }
2424 /*
2425 * Call the appropriate message handler for the object.
2426 * It is up to the message handler to free the message.
2427 * If it's a generic message, handle it generically,
2428 * otherwise call the type's message handler (if it exists).
2429 * XXX (race). Remember that a queued message may
2430 * reference a node or hook that has just been
2431 * invalidated. It will exist as the queue code
2432 * is holding a reference, but..
2433 */
2434 if ((NGI_MSG(item)->header.typecookie == NGM_GENERIC_COOKIE) &&
2435 ((NGI_MSG(item)->header.flags & NGF_RESP) == 0)) {
2436 error = ng_generic_msg(node, item, hook);
2437 break;
2438 }
2439 if (((!hook) || (!(rcvmsg = hook->hk_rcvmsg))) &&
2440 (!(rcvmsg = node->nd_type->rcvmsg))) {
2441 TRAP_ERROR();
2442 error = 0;
2443 NG_FREE_ITEM(item);
2444 break;
2445 }
2446 error = (*rcvmsg)(node, item, hook);
2447 break;
2448 case NGQF_FN:
2449 case NGQF_FN2:
2450 /*
2451 * In the case of the shutdown message we allow it to hit
2452 * even if the node is invalid.
2453 */
2454 if (NG_NODE_NOT_VALID(node) &&
2455 NGI_FN(item) != &ng_rmnode) {
2456 TRAP_ERROR();
2457 error = EINVAL;
2458 NG_FREE_ITEM(item);
2459 break;
2460 }
2461 /* Same is about some internal functions and invalid hook. */
2462 if (hook && NG_HOOK_NOT_VALID(hook) &&
2463 NGI_FN2(item) != &ng_con_part2 &&
2464 NGI_FN2(item) != &ng_con_part3 &&
2465 NGI_FN(item) != &ng_rmhook_part2) {
2466 TRAP_ERROR();
2467 error = EINVAL;
2468 NG_FREE_ITEM(item);
2469 break;
2470 }
2471
2472 if ((item->el_flags & NGQF_TYPE) == NGQF_FN) {
2473 (*NGI_FN(item))(node, hook, NGI_ARG1(item),
2474 NGI_ARG2(item));
2475 NG_FREE_ITEM(item);
2476 } else /* it is NGQF_FN2 */
2477 error = (*NGI_FN2(item))(node, item, hook);
2478 break;
2479 }
2480 /*
2481 * We held references on some of the resources
2482 * that we took from the item. Now that we have
2483 * finished doing everything, drop those references.
2484 */
2485 if (hook)
2486 NG_HOOK_UNREF(hook);
2487
2488 if (rw == NGQRW_R)
2489 ng_leave_read(node);
2490 else
2491 ng_leave_write(node);
2492
2493 /* Apply callback. */
2494 if (apply != NULL) {
2495 if (depth == 1 && error != 0)
2496 apply->error = error;
2497 if (refcount_release(&apply->refs))
2498 (*apply->apply)(apply->context, apply->error);
2499 }
2500
2501 return (error);
2502 }
2503
2504 /***********************************************************************
2505 * Implement the 'generic' control messages
2506 ***********************************************************************/
2507 static int
2508 ng_generic_msg(node_p here, item_p item, hook_p lasthook)
2509 {
2510 int error = 0;
2511 struct ng_mesg *msg;
2512 struct ng_mesg *resp = NULL;
2513
2514 NGI_GET_MSG(item, msg);
2515 if (msg->header.typecookie != NGM_GENERIC_COOKIE) {
2516 TRAP_ERROR();
2517 error = EINVAL;
2518 goto out;
2519 }
2520 switch (msg->header.cmd) {
2521 case NGM_SHUTDOWN:
2522 ng_rmnode(here, NULL, NULL, 0);
2523 break;
2524 case NGM_MKPEER:
2525 {
2526 struct ngm_mkpeer *const mkp = (struct ngm_mkpeer *) msg->data;
2527
2528 if (msg->header.arglen != sizeof(*mkp)) {
2529 TRAP_ERROR();
2530 error = EINVAL;
2531 break;
2532 }
2533 mkp->type[sizeof(mkp->type) - 1] = '\0';
2534 mkp->ourhook[sizeof(mkp->ourhook) - 1] = '\0';
2535 mkp->peerhook[sizeof(mkp->peerhook) - 1] = '\0';
2536 error = ng_mkpeer(here, mkp->ourhook, mkp->peerhook, mkp->type);
2537 break;
2538 }
2539 case NGM_CONNECT:
2540 {
2541 struct ngm_connect *const con =
2542 (struct ngm_connect *) msg->data;
2543 node_p node2;
2544
2545 if (msg->header.arglen != sizeof(*con)) {
2546 TRAP_ERROR();
2547 error = EINVAL;
2548 break;
2549 }
2550 con->path[sizeof(con->path) - 1] = '\0';
2551 con->ourhook[sizeof(con->ourhook) - 1] = '\0';
2552 con->peerhook[sizeof(con->peerhook) - 1] = '\0';
2553 /* Don't forget we get a reference.. */
2554 error = ng_path2noderef(here, con->path, &node2, NULL);
2555 if (error)
2556 break;
2557 error = ng_con_nodes(item, here, con->ourhook,
2558 node2, con->peerhook);
2559 NG_NODE_UNREF(node2);
2560 break;
2561 }
2562 case NGM_NAME:
2563 {
2564 struct ngm_name *const nam = (struct ngm_name *) msg->data;
2565
2566 if (msg->header.arglen != sizeof(*nam)) {
2567 TRAP_ERROR();
2568 error = EINVAL;
2569 break;
2570 }
2571 nam->name[sizeof(nam->name) - 1] = '\0';
2572 error = ng_name_node(here, nam->name);
2573 break;
2574 }
2575 case NGM_RMHOOK:
2576 {
2577 struct ngm_rmhook *const rmh = (struct ngm_rmhook *) msg->data;
2578 hook_p hook;
2579
2580 if (msg->header.arglen != sizeof(*rmh)) {
2581 TRAP_ERROR();
2582 error = EINVAL;
2583 break;
2584 }
2585 rmh->ourhook[sizeof(rmh->ourhook) - 1] = '\0';
2586 if ((hook = ng_findhook(here, rmh->ourhook)) != NULL)
2587 ng_destroy_hook(hook);
2588 break;
2589 }
2590 case NGM_NODEINFO:
2591 {
2592 struct nodeinfo *ni;
2593
2594 NG_MKRESPONSE(resp, msg, sizeof(*ni), M_NOWAIT);
2595 if (resp == NULL) {
2596 error = ENOMEM;
2597 break;
2598 }
2599
2600 /* Fill in node info */
2601 ni = (struct nodeinfo *) resp->data;
2602 if (NG_NODE_HAS_NAME(here))
2603 strcpy(ni->name, NG_NODE_NAME(here));
2604 strcpy(ni->type, here->nd_type->name);
2605 ni->id = ng_node2ID(here);
2606 ni->hooks = here->nd_numhooks;
2607 break;
2608 }
2609 case NGM_LISTHOOKS:
2610 {
2611 const int nhooks = here->nd_numhooks;
2612 struct hooklist *hl;
2613 struct nodeinfo *ni;
2614 hook_p hook;
2615
2616 /* Get response struct */
2617 NG_MKRESPONSE(resp, msg, sizeof(*hl) +
2618 (nhooks * sizeof(struct linkinfo)), M_NOWAIT);
2619 if (resp == NULL) {
2620 error = ENOMEM;
2621 break;
2622 }
2623 hl = (struct hooklist *) resp->data;
2624 ni = &hl->nodeinfo;
2625
2626 /* Fill in node info */
2627 if (NG_NODE_HAS_NAME(here))
2628 strcpy(ni->name, NG_NODE_NAME(here));
2629 strcpy(ni->type, here->nd_type->name);
2630 ni->id = ng_node2ID(here);
2631
2632 /* Cycle through the linked list of hooks */
2633 ni->hooks = 0;
2634 LIST_FOREACH(hook, &here->nd_hooks, hk_hooks) {
2635 struct linkinfo *const link = &hl->link[ni->hooks];
2636
2637 if (ni->hooks >= nhooks) {
2638 log(LOG_ERR, "%s: number of %s changed\n",
2639 __func__, "hooks");
2640 break;
2641 }
2642 if (NG_HOOK_NOT_VALID(hook))
2643 continue;
2644 strcpy(link->ourhook, NG_HOOK_NAME(hook));
2645 strcpy(link->peerhook, NG_PEER_HOOK_NAME(hook));
2646 if (NG_PEER_NODE_NAME(hook)[0] != '\0')
2647 strcpy(link->nodeinfo.name,
2648 NG_PEER_NODE_NAME(hook));
2649 strcpy(link->nodeinfo.type,
2650 NG_PEER_NODE(hook)->nd_type->name);
2651 link->nodeinfo.id = ng_node2ID(NG_PEER_NODE(hook));
2652 link->nodeinfo.hooks = NG_PEER_NODE(hook)->nd_numhooks;
2653 ni->hooks++;
2654 }
2655 break;
2656 }
2657
2658 case NGM_LISTNODES:
2659 {
2660 struct namelist *nl;
2661 node_p node;
2662 int i;
2663
2664 IDHASH_RLOCK();
2665 /* Get response struct. */
2666 NG_MKRESPONSE(resp, msg, sizeof(*nl) +
2667 (V_ng_nodes * sizeof(struct nodeinfo)), M_NOWAIT | M_ZERO);
2668 if (resp == NULL) {
2669 IDHASH_RUNLOCK();
2670 error = ENOMEM;
2671 break;
2672 }
2673 nl = (struct namelist *) resp->data;
2674
2675 /* Cycle through the lists of nodes. */
2676 nl->numnames = 0;
2677 for (i = 0; i <= V_ng_ID_hmask; i++) {
2678 LIST_FOREACH(node, &V_ng_ID_hash[i], nd_idnodes) {
2679 struct nodeinfo *const np =
2680 &nl->nodeinfo[nl->numnames];
2681
2682 if (NG_NODE_NOT_VALID(node))
2683 continue;
2684 if (NG_NODE_HAS_NAME(node))
2685 strcpy(np->name, NG_NODE_NAME(node));
2686 strcpy(np->type, node->nd_type->name);
2687 np->id = ng_node2ID(node);
2688 np->hooks = node->nd_numhooks;
2689 KASSERT(nl->numnames < V_ng_nodes,
2690 ("%s: no space", __func__));
2691 nl->numnames++;
2692 }
2693 }
2694 IDHASH_RUNLOCK();
2695 break;
2696 }
2697 case NGM_LISTNAMES:
2698 {
2699 struct namelist *nl;
2700 node_p node;
2701 int i;
2702
2703 NAMEHASH_RLOCK();
2704 /* Get response struct. */
2705 NG_MKRESPONSE(resp, msg, sizeof(*nl) +
2706 (V_ng_named_nodes * sizeof(struct nodeinfo)), M_NOWAIT);
2707 if (resp == NULL) {
2708 NAMEHASH_RUNLOCK();
2709 error = ENOMEM;
2710 break;
2711 }
2712 nl = (struct namelist *) resp->data;
2713
2714 /* Cycle through the lists of nodes. */
2715 nl->numnames = 0;
2716 for (i = 0; i <= V_ng_name_hmask; i++) {
2717 LIST_FOREACH(node, &V_ng_name_hash[i], nd_nodes) {
2718 struct nodeinfo *const np =
2719 &nl->nodeinfo[nl->numnames];
2720
2721 if (NG_NODE_NOT_VALID(node))
2722 continue;
2723 strcpy(np->name, NG_NODE_NAME(node));
2724 strcpy(np->type, node->nd_type->name);
2725 np->id = ng_node2ID(node);
2726 np->hooks = node->nd_numhooks;
2727 KASSERT(nl->numnames < V_ng_named_nodes,
2728 ("%s: no space", __func__));
2729 nl->numnames++;
2730 }
2731 }
2732 NAMEHASH_RUNLOCK();
2733 break;
2734 }
2735
2736 case NGM_LISTTYPES:
2737 {
2738 struct typelist *tl;
2739 struct ng_type *type;
2740 int num = 0;
2741
2742 TYPELIST_RLOCK();
2743 /* Count number of types */
2744 LIST_FOREACH(type, &ng_typelist, types)
2745 num++;
2746
2747 /* Get response struct */
2748 NG_MKRESPONSE(resp, msg, sizeof(*tl) +
2749 (num * sizeof(struct typeinfo)), M_NOWAIT);
2750 if (resp == NULL) {
2751 TYPELIST_RUNLOCK();
2752 error = ENOMEM;
2753 break;
2754 }
2755 tl = (struct typelist *) resp->data;
2756
2757 /* Cycle through the linked list of types */
2758 tl->numtypes = 0;
2759 LIST_FOREACH(type, &ng_typelist, types) {
2760 struct typeinfo *const tp = &tl->typeinfo[tl->numtypes];
2761
2762 strcpy(tp->type_name, type->name);
2763 tp->numnodes = type->refs - 1; /* don't count list */
2764 KASSERT(tl->numtypes < num, ("%s: no space", __func__));
2765 tl->numtypes++;
2766 }
2767 TYPELIST_RUNLOCK();
2768 break;
2769 }
2770
2771 case NGM_BINARY2ASCII:
2772 {
2773 int bufSize = 20 * 1024; /* XXX hard coded constant */
2774 const struct ng_parse_type *argstype;
2775 const struct ng_cmdlist *c;
2776 struct ng_mesg *binary, *ascii;
2777
2778 /* Data area must contain a valid netgraph message */
2779 binary = (struct ng_mesg *)msg->data;
2780 if (msg->header.arglen < sizeof(struct ng_mesg) ||
2781 (msg->header.arglen - sizeof(struct ng_mesg) <
2782 binary->header.arglen)) {
2783 TRAP_ERROR();
2784 error = EINVAL;
2785 break;
2786 }
2787
2788 /* Get a response message with lots of room */
2789 NG_MKRESPONSE(resp, msg, sizeof(*ascii) + bufSize, M_NOWAIT);
2790 if (resp == NULL) {
2791 error = ENOMEM;
2792 break;
2793 }
2794 ascii = (struct ng_mesg *)resp->data;
2795
2796 /* Copy binary message header to response message payload */
2797 bcopy(binary, ascii, sizeof(*binary));
2798
2799 /* Find command by matching typecookie and command number */
2800 for (c = here->nd_type->cmdlist; c != NULL && c->name != NULL;
2801 c++) {
2802 if (binary->header.typecookie == c->cookie &&
2803 binary->header.cmd == c->cmd)
2804 break;
2805 }
2806 if (c == NULL || c->name == NULL) {
2807 for (c = ng_generic_cmds; c->name != NULL; c++) {
2808 if (binary->header.typecookie == c->cookie &&
2809 binary->header.cmd == c->cmd)
2810 break;
2811 }
2812 if (c->name == NULL) {
2813 NG_FREE_MSG(resp);
2814 error = ENOSYS;
2815 break;
2816 }
2817 }
2818
2819 /* Convert command name to ASCII */
2820 snprintf(ascii->header.cmdstr, sizeof(ascii->header.cmdstr),
2821 "%s", c->name);
2822
2823 /* Convert command arguments to ASCII */
2824 argstype = (binary->header.flags & NGF_RESP) ?
2825 c->respType : c->mesgType;
2826 if (argstype == NULL) {
2827 *ascii->data = '\0';
2828 } else {
2829 if ((error = ng_unparse(argstype,
2830 (u_char *)binary->data,
2831 ascii->data, bufSize)) != 0) {
2832 NG_FREE_MSG(resp);
2833 break;
2834 }
2835 }
2836
2837 /* Return the result as struct ng_mesg plus ASCII string */
2838 bufSize = strlen(ascii->data) + 1;
2839 ascii->header.arglen = bufSize;
2840 resp->header.arglen = sizeof(*ascii) + bufSize;
2841 break;
2842 }
2843
2844 case NGM_ASCII2BINARY:
2845 {
2846 int bufSize = 20 * 1024; /* XXX hard coded constant */
2847 const struct ng_cmdlist *c;
2848 const struct ng_parse_type *argstype;
2849 struct ng_mesg *ascii, *binary;
2850 int off = 0;
2851
2852 /* Data area must contain at least a struct ng_mesg + '\0' */
2853 ascii = (struct ng_mesg *)msg->data;
2854 if ((msg->header.arglen < sizeof(*ascii) + 1) ||
2855 (ascii->header.arglen < 1) ||
2856 (msg->header.arglen < sizeof(*ascii) +
2857 ascii->header.arglen)) {
2858 TRAP_ERROR();
2859 error = EINVAL;
2860 break;
2861 }
2862 ascii->data[ascii->header.arglen - 1] = '\0';
2863
2864 /* Get a response message with lots of room */
2865 NG_MKRESPONSE(resp, msg, sizeof(*binary) + bufSize, M_NOWAIT);
2866 if (resp == NULL) {
2867 error = ENOMEM;
2868 break;
2869 }
2870 binary = (struct ng_mesg *)resp->data;
2871
2872 /* Copy ASCII message header to response message payload */
2873 bcopy(ascii, binary, sizeof(*ascii));
2874
2875 /* Find command by matching ASCII command string */
2876 for (c = here->nd_type->cmdlist;
2877 c != NULL && c->name != NULL; c++) {
2878 if (strcmp(ascii->header.cmdstr, c->name) == 0)
2879 break;
2880 }
2881 if (c == NULL || c->name == NULL) {
2882 for (c = ng_generic_cmds; c->name != NULL; c++) {
2883 if (strcmp(ascii->header.cmdstr, c->name) == 0)
2884 break;
2885 }
2886 if (c->name == NULL) {
2887 NG_FREE_MSG(resp);
2888 error = ENOSYS;
2889 break;
2890 }
2891 }
2892
2893 /* Convert command name to binary */
2894 binary->header.cmd = c->cmd;
2895 binary->header.typecookie = c->cookie;
2896
2897 /* Convert command arguments to binary */
2898 argstype = (binary->header.flags & NGF_RESP) ?
2899 c->respType : c->mesgType;
2900 if (argstype == NULL) {
2901 bufSize = 0;
2902 } else {
2903 if ((error = ng_parse(argstype, ascii->data, &off,
2904 (u_char *)binary->data, &bufSize)) != 0) {
2905 NG_FREE_MSG(resp);
2906 break;
2907 }
2908 }
2909
2910 /* Return the result */
2911 binary->header.arglen = bufSize;
2912 resp->header.arglen = sizeof(*binary) + bufSize;
2913 break;
2914 }
2915
2916 case NGM_TEXT_CONFIG:
2917 case NGM_TEXT_STATUS:
2918 /*
2919 * This one is tricky as it passes the command down to the
2920 * actual node, even though it is a generic type command.
2921 * This means we must assume that the item/msg is already freed
2922 * when control passes back to us.
2923 */
2924 if (here->nd_type->rcvmsg != NULL) {
2925 NGI_MSG(item) = msg; /* put it back as we found it */
2926 return((*here->nd_type->rcvmsg)(here, item, lasthook));
2927 }
2928 /* Fall through if rcvmsg not supported */
2929 default:
2930 TRAP_ERROR();
2931 error = EINVAL;
2932 }
2933 /*
2934 * Sometimes a generic message may be statically allocated
2935 * to avoid problems with allocating when in tight memory situations.
2936 * Don't free it if it is so.
2937 * I break them appart here, because erros may cause a free if the item
2938 * in which case we'd be doing it twice.
2939 * they are kept together above, to simplify freeing.
2940 */
2941 out:
2942 NG_RESPOND_MSG(error, here, item, resp);
2943 NG_FREE_MSG(msg);
2944 return (error);
2945 }
2946
2947 /************************************************************************
2948 Queue element get/free routines
2949 ************************************************************************/
2950
2951 uma_zone_t ng_qzone;
2952 uma_zone_t ng_qdzone;
2953 static int numthreads = 0; /* number of queue threads */
2954 static int maxalloc = 4096;/* limit the damage of a leak */
2955 static int maxdata = 512; /* limit the damage of a DoS */
2956
2957 TUNABLE_INT("net.graph.threads", &numthreads);
2958 SYSCTL_INT(_net_graph, OID_AUTO, threads, CTLFLAG_RDTUN, &numthreads,
2959 0, "Number of queue processing threads");
2960 TUNABLE_INT("net.graph.maxalloc", &maxalloc);
2961 SYSCTL_INT(_net_graph, OID_AUTO, maxalloc, CTLFLAG_RDTUN, &maxalloc,
2962 0, "Maximum number of non-data queue items to allocate");
2963 TUNABLE_INT("net.graph.maxdata", &maxdata);
2964 SYSCTL_INT(_net_graph, OID_AUTO, maxdata, CTLFLAG_RDTUN, &maxdata,
2965 0, "Maximum number of data queue items to allocate");
2966
2967 #ifdef NETGRAPH_DEBUG
2968 static TAILQ_HEAD(, ng_item) ng_itemlist = TAILQ_HEAD_INITIALIZER(ng_itemlist);
2969 static int allocated; /* number of items malloc'd */
2970 #endif
2971
2972 /*
2973 * Get a queue entry.
2974 * This is usually called when a packet first enters netgraph.
2975 * By definition, this is usually from an interrupt, or from a user.
2976 * Users are not so important, but try be quick for the times that it's
2977 * an interrupt.
2978 */
2979 static __inline item_p
2980 ng_alloc_item(int type, int flags)
2981 {
2982 item_p item;
2983
2984 KASSERT(((type & ~NGQF_TYPE) == 0),
2985 ("%s: incorrect item type: %d", __func__, type));
2986
2987 item = uma_zalloc((type == NGQF_DATA) ? ng_qdzone : ng_qzone,
2988 ((flags & NG_WAITOK) ? M_WAITOK : M_NOWAIT) | M_ZERO);
2989
2990 if (item) {
2991 item->el_flags = type;
2992 #ifdef NETGRAPH_DEBUG
2993 mtx_lock(&ngq_mtx);
2994 TAILQ_INSERT_TAIL(&ng_itemlist, item, all);
2995 allocated++;
2996 mtx_unlock(&ngq_mtx);
2997 #endif
2998 }
2999
3000 return (item);
3001 }
3002
3003 /*
3004 * Release a queue entry
3005 */
3006 void
3007 ng_free_item(item_p item)
3008 {
3009 /*
3010 * The item may hold resources on it's own. We need to free
3011 * these before we can free the item. What they are depends upon
3012 * what kind of item it is. it is important that nodes zero
3013 * out pointers to resources that they remove from the item
3014 * or we release them again here.
3015 */
3016 switch (item->el_flags & NGQF_TYPE) {
3017 case NGQF_DATA:
3018 /* If we have an mbuf still attached.. */
3019 NG_FREE_M(_NGI_M(item));
3020 break;
3021 case NGQF_MESG:
3022 _NGI_RETADDR(item) = 0;
3023 NG_FREE_MSG(_NGI_MSG(item));
3024 break;
3025 case NGQF_FN:
3026 case NGQF_FN2:
3027 /* nothing to free really, */
3028 _NGI_FN(item) = NULL;
3029 _NGI_ARG1(item) = NULL;
3030 _NGI_ARG2(item) = 0;
3031 break;
3032 }
3033 /* If we still have a node or hook referenced... */
3034 _NGI_CLR_NODE(item);
3035 _NGI_CLR_HOOK(item);
3036
3037 #ifdef NETGRAPH_DEBUG
3038 mtx_lock(&ngq_mtx);
3039 TAILQ_REMOVE(&ng_itemlist, item, all);
3040 allocated--;
3041 mtx_unlock(&ngq_mtx);
3042 #endif
3043 uma_zfree(((item->el_flags & NGQF_TYPE) == NGQF_DATA) ?
3044 ng_qdzone : ng_qzone, item);
3045 }
3046
3047 /*
3048 * Change type of the queue entry.
3049 * Possibly reallocates it from another UMA zone.
3050 */
3051 static __inline item_p
3052 ng_realloc_item(item_p pitem, int type, int flags)
3053 {
3054 item_p item;
3055 int from, to;
3056
3057 KASSERT((pitem != NULL), ("%s: can't reallocate NULL", __func__));
3058 KASSERT(((type & ~NGQF_TYPE) == 0),
3059 ("%s: incorrect item type: %d", __func__, type));
3060
3061 from = ((pitem->el_flags & NGQF_TYPE) == NGQF_DATA);
3062 to = (type == NGQF_DATA);
3063 if (from != to) {
3064 /* If reallocation is required do it and copy item. */
3065 if ((item = ng_alloc_item(type, flags)) == NULL) {
3066 ng_free_item(pitem);
3067 return (NULL);
3068 }
3069 *item = *pitem;
3070 ng_free_item(pitem);
3071 } else
3072 item = pitem;
3073 item->el_flags = (item->el_flags & ~NGQF_TYPE) | type;
3074
3075 return (item);
3076 }
3077
3078 /************************************************************************
3079 Module routines
3080 ************************************************************************/
3081
3082 /*
3083 * Handle the loading/unloading of a netgraph node type module
3084 */
3085 int
3086 ng_mod_event(module_t mod, int event, void *data)
3087 {
3088 struct ng_type *const type = data;
3089 int error = 0;
3090
3091 switch (event) {
3092 case MOD_LOAD:
3093
3094 /* Register new netgraph node type */
3095 if ((error = ng_newtype(type)) != 0)
3096 break;
3097
3098 /* Call type specific code */
3099 if (type->mod_event != NULL)
3100 if ((error = (*type->mod_event)(mod, event, data))) {
3101 TYPELIST_WLOCK();
3102 type->refs--; /* undo it */
3103 LIST_REMOVE(type, types);
3104 TYPELIST_WUNLOCK();
3105 }
3106 break;
3107
3108 case MOD_UNLOAD:
3109 if (type->refs > 1) { /* make sure no nodes exist! */
3110 error = EBUSY;
3111 } else {
3112 if (type->refs == 0) /* failed load, nothing to undo */
3113 break;
3114 if (type->mod_event != NULL) { /* check with type */
3115 error = (*type->mod_event)(mod, event, data);
3116 if (error != 0) /* type refuses.. */
3117 break;
3118 }
3119 TYPELIST_WLOCK();
3120 LIST_REMOVE(type, types);
3121 TYPELIST_WUNLOCK();
3122 }
3123 break;
3124
3125 default:
3126 if (type->mod_event != NULL)
3127 error = (*type->mod_event)(mod, event, data);
3128 else
3129 error = EOPNOTSUPP; /* XXX ? */
3130 break;
3131 }
3132 return (error);
3133 }
3134
3135 static void
3136 vnet_netgraph_init(const void *unused __unused)
3137 {
3138
3139 /* We start with small hashes, but they can grow. */
3140 V_ng_ID_hash = hashinit(16, M_NETGRAPH_NODE, &V_ng_ID_hmask);
3141 V_ng_name_hash = hashinit(16, M_NETGRAPH_NODE, &V_ng_name_hmask);
3142 }
3143 VNET_SYSINIT(vnet_netgraph_init, SI_SUB_NETGRAPH, SI_ORDER_FIRST,
3144 vnet_netgraph_init, NULL);
3145
3146 #ifdef VIMAGE
3147 static void
3148 vnet_netgraph_uninit(const void *unused __unused)
3149 {
3150 node_p node = NULL, last_killed = NULL;
3151 int i;
3152
3153 do {
3154 /* Find a node to kill */
3155 IDHASH_RLOCK();
3156 for (i = 0; i <= V_ng_ID_hmask; i++) {
3157 LIST_FOREACH(node, &V_ng_ID_hash[i], nd_idnodes) {
3158 if (node != &ng_deadnode) {
3159 NG_NODE_REF(node);
3160 break;
3161 }
3162 }
3163 if (node != NULL)
3164 break;
3165 }
3166 IDHASH_RUNLOCK();
3167
3168 /* Attempt to kill it only if it is a regular node */
3169 if (node != NULL) {
3170 if (node == last_killed) {
3171 /* This should never happen */
3172 printf("ng node %s needs NGF_REALLY_DIE\n",
3173 node->nd_name);
3174 if (node->nd_flags & NGF_REALLY_DIE)
3175 panic("ng node %s won't die",
3176 node->nd_name);
3177 node->nd_flags |= NGF_REALLY_DIE;
3178 }
3179 ng_rmnode(node, NULL, NULL, 0);
3180 NG_NODE_UNREF(node);
3181 last_killed = node;
3182 }
3183 } while (node != NULL);
3184
3185 hashdestroy(V_ng_name_hash, M_NETGRAPH_NODE, V_ng_name_hmask);
3186 hashdestroy(V_ng_ID_hash, M_NETGRAPH_NODE, V_ng_ID_hmask);
3187 }
3188 VNET_SYSUNINIT(vnet_netgraph_uninit, SI_SUB_NETGRAPH, SI_ORDER_FIRST,
3189 vnet_netgraph_uninit, NULL);
3190 #endif /* VIMAGE */
3191
3192 /*
3193 * Handle loading and unloading for this code.
3194 * The only thing we need to link into is the NETISR strucure.
3195 */
3196 static int
3197 ngb_mod_event(module_t mod, int event, void *data)
3198 {
3199 struct proc *p;
3200 struct thread *td;
3201 int i, error = 0;
3202
3203 switch (event) {
3204 case MOD_LOAD:
3205 /* Initialize everything. */
3206 NG_WORKLIST_LOCK_INIT();
3207 rw_init(&ng_typelist_lock, "netgraph types");
3208 rw_init(&ng_idhash_lock, "netgraph idhash");
3209 rw_init(&ng_namehash_lock, "netgraph namehash");
3210 rw_init(&ng_topo_lock, "netgraph topology mutex");
3211 #ifdef NETGRAPH_DEBUG
3212 mtx_init(&ng_nodelist_mtx, "netgraph nodelist mutex", NULL,
3213 MTX_DEF);
3214 mtx_init(&ngq_mtx, "netgraph item list mutex", NULL,
3215 MTX_DEF);
3216 #endif
3217 ng_qzone = uma_zcreate("NetGraph items", sizeof(struct ng_item),
3218 NULL, NULL, NULL, NULL, UMA_ALIGN_CACHE, 0);
3219 uma_zone_set_max(ng_qzone, maxalloc);
3220 ng_qdzone = uma_zcreate("NetGraph data items",
3221 sizeof(struct ng_item), NULL, NULL, NULL, NULL,
3222 UMA_ALIGN_CACHE, 0);
3223 uma_zone_set_max(ng_qdzone, maxdata);
3224 /* Autoconfigure number of threads. */
3225 if (numthreads <= 0)
3226 numthreads = mp_ncpus;
3227 /* Create threads. */
3228 p = NULL; /* start with no process */
3229 for (i = 0; i < numthreads; i++) {
3230 if (kproc_kthread_add(ngthread, NULL, &p, &td,
3231 RFHIGHPID, 0, "ng_queue", "ng_queue%d", i)) {
3232 numthreads = i;
3233 break;
3234 }
3235 }
3236 break;
3237 case MOD_UNLOAD:
3238 /* You can't unload it because an interface may be using it. */
3239 error = EBUSY;
3240 break;
3241 default:
3242 error = EOPNOTSUPP;
3243 break;
3244 }
3245 return (error);
3246 }
3247
3248 static moduledata_t netgraph_mod = {
3249 "netgraph",
3250 ngb_mod_event,
3251 (NULL)
3252 };
3253 DECLARE_MODULE(netgraph, netgraph_mod, SI_SUB_NETGRAPH, SI_ORDER_FIRST);
3254 SYSCTL_NODE(_net, OID_AUTO, graph, CTLFLAG_RW, 0, "netgraph Family");
3255 SYSCTL_INT(_net_graph, OID_AUTO, abi_version, CTLFLAG_RD, SYSCTL_NULL_INT_PTR, NG_ABI_VERSION,"");
3256 SYSCTL_INT(_net_graph, OID_AUTO, msg_version, CTLFLAG_RD, SYSCTL_NULL_INT_PTR, NG_VERSION, "");
3257
3258 #ifdef NETGRAPH_DEBUG
3259 void
3260 dumphook (hook_p hook, char *file, int line)
3261 {
3262 printf("hook: name %s, %d refs, Last touched:\n",
3263 _NG_HOOK_NAME(hook), hook->hk_refs);
3264 printf(" Last active @ %s, line %d\n",
3265 hook->lastfile, hook->lastline);
3266 if (line) {
3267 printf(" problem discovered at file %s, line %d\n", file, line);
3268 #ifdef KDB
3269 kdb_backtrace();
3270 #endif
3271 }
3272 }
3273
3274 void
3275 dumpnode(node_p node, char *file, int line)
3276 {
3277 printf("node: ID [%x]: type '%s', %d hooks, flags 0x%x, %d refs, %s:\n",
3278 _NG_NODE_ID(node), node->nd_type->name,
3279 node->nd_numhooks, node->nd_flags,
3280 node->nd_refs, node->nd_name);
3281 printf(" Last active @ %s, line %d\n",
3282 node->lastfile, node->lastline);
3283 if (line) {
3284 printf(" problem discovered at file %s, line %d\n", file, line);
3285 #ifdef KDB
3286 kdb_backtrace();
3287 #endif
3288 }
3289 }
3290
3291 void
3292 dumpitem(item_p item, char *file, int line)
3293 {
3294 printf(" ACTIVE item, last used at %s, line %d",
3295 item->lastfile, item->lastline);
3296 switch(item->el_flags & NGQF_TYPE) {
3297 case NGQF_DATA:
3298 printf(" - [data]\n");
3299 break;
3300 case NGQF_MESG:
3301 printf(" - retaddr[%d]:\n", _NGI_RETADDR(item));
3302 break;
3303 case NGQF_FN:
3304 printf(" - fn@%p (%p, %p, %p, %d (%x))\n",
3305 _NGI_FN(item),
3306 _NGI_NODE(item),
3307 _NGI_HOOK(item),
3308 item->body.fn.fn_arg1,
3309 item->body.fn.fn_arg2,
3310 item->body.fn.fn_arg2);
3311 break;
3312 case NGQF_FN2:
3313 printf(" - fn2@%p (%p, %p, %p, %d (%x))\n",
3314 _NGI_FN2(item),
3315 _NGI_NODE(item),
3316 _NGI_HOOK(item),
3317 item->body.fn.fn_arg1,
3318 item->body.fn.fn_arg2,
3319 item->body.fn.fn_arg2);
3320 break;
3321 }
3322 if (line) {
3323 printf(" problem discovered at file %s, line %d\n", file, line);
3324 if (_NGI_NODE(item)) {
3325 printf("node %p ([%x])\n",
3326 _NGI_NODE(item), ng_node2ID(_NGI_NODE(item)));
3327 }
3328 }
3329 }
3330
3331 static void
3332 ng_dumpitems(void)
3333 {
3334 item_p item;
3335 int i = 1;
3336 TAILQ_FOREACH(item, &ng_itemlist, all) {
3337 printf("[%d] ", i++);
3338 dumpitem(item, NULL, 0);
3339 }
3340 }
3341
3342 static void
3343 ng_dumpnodes(void)
3344 {
3345 node_p node;
3346 int i = 1;
3347 mtx_lock(&ng_nodelist_mtx);
3348 SLIST_FOREACH(node, &ng_allnodes, nd_all) {
3349 printf("[%d] ", i++);
3350 dumpnode(node, NULL, 0);
3351 }
3352 mtx_unlock(&ng_nodelist_mtx);
3353 }
3354
3355 static void
3356 ng_dumphooks(void)
3357 {
3358 hook_p hook;
3359 int i = 1;
3360 mtx_lock(&ng_nodelist_mtx);
3361 SLIST_FOREACH(hook, &ng_allhooks, hk_all) {
3362 printf("[%d] ", i++);
3363 dumphook(hook, NULL, 0);
3364 }
3365 mtx_unlock(&ng_nodelist_mtx);
3366 }
3367
3368 static int
3369 sysctl_debug_ng_dump_items(SYSCTL_HANDLER_ARGS)
3370 {
3371 int error;
3372 int val;
3373 int i;
3374
3375 val = allocated;
3376 i = 1;
3377 error = sysctl_handle_int(oidp, &val, 0, req);
3378 if (error != 0 || req->newptr == NULL)
3379 return (error);
3380 if (val == 42) {
3381 ng_dumpitems();
3382 ng_dumpnodes();
3383 ng_dumphooks();
3384 }
3385 return (0);
3386 }
3387
3388 SYSCTL_PROC(_debug, OID_AUTO, ng_dump_items, CTLTYPE_INT | CTLFLAG_RW,
3389 0, sizeof(int), sysctl_debug_ng_dump_items, "I", "Number of allocated items");
3390 #endif /* NETGRAPH_DEBUG */
3391
3392 /***********************************************************************
3393 * Worklist routines
3394 **********************************************************************/
3395 /*
3396 * Pick a node off the list of nodes with work,
3397 * try get an item to process off it. Remove the node from the list.
3398 */
3399 static void
3400 ngthread(void *arg)
3401 {
3402 for (;;) {
3403 node_p node;
3404
3405 /* Get node from the worklist. */
3406 NG_WORKLIST_LOCK();
3407 while ((node = STAILQ_FIRST(&ng_worklist)) == NULL)
3408 NG_WORKLIST_SLEEP();
3409 STAILQ_REMOVE_HEAD(&ng_worklist, nd_input_queue.q_work);
3410 NG_WORKLIST_UNLOCK();
3411 CURVNET_SET(node->nd_vnet);
3412 CTR3(KTR_NET, "%20s: node [%x] (%p) taken off worklist",
3413 __func__, node->nd_ID, node);
3414 /*
3415 * We have the node. We also take over the reference
3416 * that the list had on it.
3417 * Now process as much as you can, until it won't
3418 * let you have another item off the queue.
3419 * All this time, keep the reference
3420 * that lets us be sure that the node still exists.
3421 * Let the reference go at the last minute.
3422 */
3423 for (;;) {
3424 item_p item;
3425 int rw;
3426
3427 NG_QUEUE_LOCK(&node->nd_input_queue);
3428 item = ng_dequeue(node, &rw);
3429 if (item == NULL) {
3430 node->nd_input_queue.q_flags2 &= ~NGQ2_WORKQ;
3431 NG_QUEUE_UNLOCK(&node->nd_input_queue);
3432 break; /* go look for another node */
3433 } else {
3434 NG_QUEUE_UNLOCK(&node->nd_input_queue);
3435 NGI_GET_NODE(item, node); /* zaps stored node */
3436 ng_apply_item(node, item, rw);
3437 NG_NODE_UNREF(node);
3438 }
3439 }
3440 NG_NODE_UNREF(node);
3441 CURVNET_RESTORE();
3442 }
3443 }
3444
3445 /*
3446 * XXX
3447 * It's posible that a debugging NG_NODE_REF may need
3448 * to be outside the mutex zone
3449 */
3450 static void
3451 ng_worklist_add(node_p node)
3452 {
3453
3454 mtx_assert(&node->nd_input_queue.q_mtx, MA_OWNED);
3455
3456 if ((node->nd_input_queue.q_flags2 & NGQ2_WORKQ) == 0) {
3457 /*
3458 * If we are not already on the work queue,
3459 * then put us on.
3460 */
3461 node->nd_input_queue.q_flags2 |= NGQ2_WORKQ;
3462 NG_NODE_REF(node); /* XXX safe in mutex? */
3463 NG_WORKLIST_LOCK();
3464 STAILQ_INSERT_TAIL(&ng_worklist, node, nd_input_queue.q_work);
3465 NG_WORKLIST_UNLOCK();
3466 CTR3(KTR_NET, "%20s: node [%x] (%p) put on worklist", __func__,
3467 node->nd_ID, node);
3468 NG_WORKLIST_WAKEUP();
3469 } else {
3470 CTR3(KTR_NET, "%20s: node [%x] (%p) already on worklist",
3471 __func__, node->nd_ID, node);
3472 }
3473 }
3474
3475 /***********************************************************************
3476 * Externally useable functions to set up a queue item ready for sending
3477 ***********************************************************************/
3478
3479 #ifdef NETGRAPH_DEBUG
3480 #define ITEM_DEBUG_CHECKS \
3481 do { \
3482 if (NGI_NODE(item) ) { \
3483 printf("item already has node"); \
3484 kdb_enter(KDB_WHY_NETGRAPH, "has node"); \
3485 NGI_CLR_NODE(item); \
3486 } \
3487 if (NGI_HOOK(item) ) { \
3488 printf("item already has hook"); \
3489 kdb_enter(KDB_WHY_NETGRAPH, "has hook"); \
3490 NGI_CLR_HOOK(item); \
3491 } \
3492 } while (0)
3493 #else
3494 #define ITEM_DEBUG_CHECKS
3495 #endif
3496
3497 /*
3498 * Put mbuf into the item.
3499 * Hook and node references will be removed when the item is dequeued.
3500 * (or equivalent)
3501 * (XXX) Unsafe because no reference held by peer on remote node.
3502 * remote node might go away in this timescale.
3503 * We know the hooks can't go away because that would require getting
3504 * a writer item on both nodes and we must have at least a reader
3505 * here to be able to do this.
3506 * Note that the hook loaded is the REMOTE hook.
3507 *
3508 * This is possibly in the critical path for new data.
3509 */
3510 item_p
3511 ng_package_data(struct mbuf *m, int flags)
3512 {
3513 item_p item;
3514
3515 if ((item = ng_alloc_item(NGQF_DATA, flags)) == NULL) {
3516 NG_FREE_M(m);
3517 return (NULL);
3518 }
3519 ITEM_DEBUG_CHECKS;
3520 item->el_flags |= NGQF_READER;
3521 NGI_M(item) = m;
3522 return (item);
3523 }
3524
3525 /*
3526 * Allocate a queue item and put items into it..
3527 * Evaluate the address as this will be needed to queue it and
3528 * to work out what some of the fields should be.
3529 * Hook and node references will be removed when the item is dequeued.
3530 * (or equivalent)
3531 */
3532 item_p
3533 ng_package_msg(struct ng_mesg *msg, int flags)
3534 {
3535 item_p item;
3536
3537 if ((item = ng_alloc_item(NGQF_MESG, flags)) == NULL) {
3538 NG_FREE_MSG(msg);
3539 return (NULL);
3540 }
3541 ITEM_DEBUG_CHECKS;
3542 /* Messages items count as writers unless explicitly exempted. */
3543 if (msg->header.cmd & NGM_READONLY)
3544 item->el_flags |= NGQF_READER;
3545 else
3546 item->el_flags |= NGQF_WRITER;
3547 /*
3548 * Set the current lasthook into the queue item
3549 */
3550 NGI_MSG(item) = msg;
3551 NGI_RETADDR(item) = 0;
3552 return (item);
3553 }
3554
3555 #define SET_RETADDR(item, here, retaddr) \
3556 do { /* Data or fn items don't have retaddrs */ \
3557 if ((item->el_flags & NGQF_TYPE) == NGQF_MESG) { \
3558 if (retaddr) { \
3559 NGI_RETADDR(item) = retaddr; \
3560 } else { \
3561 /* \
3562 * The old return address should be ok. \
3563 * If there isn't one, use the address \
3564 * here. \
3565 */ \
3566 if (NGI_RETADDR(item) == 0) { \
3567 NGI_RETADDR(item) \
3568 = ng_node2ID(here); \
3569 } \
3570 } \
3571 } \
3572 } while (0)
3573
3574 int
3575 ng_address_hook(node_p here, item_p item, hook_p hook, ng_ID_t retaddr)
3576 {
3577 hook_p peer;
3578 node_p peernode;
3579 ITEM_DEBUG_CHECKS;
3580 /*
3581 * Quick sanity check..
3582 * Since a hook holds a reference on it's node, once we know
3583 * that the peer is still connected (even if invalid,) we know
3584 * that the peer node is present, though maybe invalid.
3585 */
3586 TOPOLOGY_RLOCK();
3587 if ((hook == NULL) || NG_HOOK_NOT_VALID(hook) ||
3588 NG_HOOK_NOT_VALID(peer = NG_HOOK_PEER(hook)) ||
3589 NG_NODE_NOT_VALID(peernode = NG_PEER_NODE(hook))) {
3590 NG_FREE_ITEM(item);
3591 TRAP_ERROR();
3592 TOPOLOGY_RUNLOCK();
3593 return (ENETDOWN);
3594 }
3595
3596 /*
3597 * Transfer our interest to the other (peer) end.
3598 */
3599 NG_HOOK_REF(peer);
3600 NG_NODE_REF(peernode);
3601 NGI_SET_HOOK(item, peer);
3602 NGI_SET_NODE(item, peernode);
3603 SET_RETADDR(item, here, retaddr);
3604
3605 TOPOLOGY_RUNLOCK();
3606
3607 return (0);
3608 }
3609
3610 int
3611 ng_address_path(node_p here, item_p item, char *address, ng_ID_t retaddr)
3612 {
3613 node_p dest = NULL;
3614 hook_p hook = NULL;
3615 int error;
3616
3617 ITEM_DEBUG_CHECKS;
3618 /*
3619 * Note that ng_path2noderef increments the reference count
3620 * on the node for us if it finds one. So we don't have to.
3621 */
3622 error = ng_path2noderef(here, address, &dest, &hook);
3623 if (error) {
3624 NG_FREE_ITEM(item);
3625 return (error);
3626 }
3627 NGI_SET_NODE(item, dest);
3628 if (hook)
3629 NGI_SET_HOOK(item, hook);
3630
3631 SET_RETADDR(item, here, retaddr);
3632 return (0);
3633 }
3634
3635 int
3636 ng_address_ID(node_p here, item_p item, ng_ID_t ID, ng_ID_t retaddr)
3637 {
3638 node_p dest;
3639
3640 ITEM_DEBUG_CHECKS;
3641 /*
3642 * Find the target node.
3643 */
3644 dest = ng_ID2noderef(ID); /* GETS REFERENCE! */
3645 if (dest == NULL) {
3646 NG_FREE_ITEM(item);
3647 TRAP_ERROR();
3648 return(EINVAL);
3649 }
3650 /* Fill out the contents */
3651 NGI_SET_NODE(item, dest);
3652 NGI_CLR_HOOK(item);
3653 SET_RETADDR(item, here, retaddr);
3654 return (0);
3655 }
3656
3657 /*
3658 * special case to send a message to self (e.g. destroy node)
3659 * Possibly indicate an arrival hook too.
3660 * Useful for removing that hook :-)
3661 */
3662 item_p
3663 ng_package_msg_self(node_p here, hook_p hook, struct ng_mesg *msg)
3664 {
3665 item_p item;
3666
3667 /*
3668 * Find the target node.
3669 * If there is a HOOK argument, then use that in preference
3670 * to the address.
3671 */
3672 if ((item = ng_alloc_item(NGQF_MESG, NG_NOFLAGS)) == NULL) {
3673 NG_FREE_MSG(msg);
3674 return (NULL);
3675 }
3676
3677 /* Fill out the contents */
3678 item->el_flags |= NGQF_WRITER;
3679 NG_NODE_REF(here);
3680 NGI_SET_NODE(item, here);
3681 if (hook) {
3682 NG_HOOK_REF(hook);
3683 NGI_SET_HOOK(item, hook);
3684 }
3685 NGI_MSG(item) = msg;
3686 NGI_RETADDR(item) = ng_node2ID(here);
3687 return (item);
3688 }
3689
3690 /*
3691 * Send ng_item_fn function call to the specified node.
3692 */
3693
3694 int
3695 ng_send_fn(node_p node, hook_p hook, ng_item_fn *fn, void * arg1, int arg2)
3696 {
3697
3698 return ng_send_fn1(node, hook, fn, arg1, arg2, NG_NOFLAGS);
3699 }
3700
3701 int
3702 ng_send_fn1(node_p node, hook_p hook, ng_item_fn *fn, void * arg1, int arg2,
3703 int flags)
3704 {
3705 item_p item;
3706
3707 if ((item = ng_alloc_item(NGQF_FN, flags)) == NULL) {
3708 return (ENOMEM);
3709 }
3710 item->el_flags |= NGQF_WRITER;
3711 NG_NODE_REF(node); /* and one for the item */
3712 NGI_SET_NODE(item, node);
3713 if (hook) {
3714 NG_HOOK_REF(hook);
3715 NGI_SET_HOOK(item, hook);
3716 }
3717 NGI_FN(item) = fn;
3718 NGI_ARG1(item) = arg1;
3719 NGI_ARG2(item) = arg2;
3720 return(ng_snd_item(item, flags));
3721 }
3722
3723 /*
3724 * Send ng_item_fn2 function call to the specified node.
3725 *
3726 * If an optional pitem parameter is supplied, its apply
3727 * callback will be copied to the new item. If also NG_REUSE_ITEM
3728 * flag is set, no new item will be allocated, but pitem will
3729 * be used.
3730 */
3731 int
3732 ng_send_fn2(node_p node, hook_p hook, item_p pitem, ng_item_fn2 *fn, void *arg1,
3733 int arg2, int flags)
3734 {
3735 item_p item;
3736
3737 KASSERT((pitem != NULL || (flags & NG_REUSE_ITEM) == 0),
3738 ("%s: NG_REUSE_ITEM but no pitem", __func__));
3739
3740 /*
3741 * Allocate a new item if no supplied or
3742 * if we can't use supplied one.
3743 */
3744 if (pitem == NULL || (flags & NG_REUSE_ITEM) == 0) {
3745 if ((item = ng_alloc_item(NGQF_FN2, flags)) == NULL)
3746 return (ENOMEM);
3747 if (pitem != NULL)
3748 item->apply = pitem->apply;
3749 } else {
3750 if ((item = ng_realloc_item(pitem, NGQF_FN2, flags)) == NULL)
3751 return (ENOMEM);
3752 }
3753
3754 item->el_flags = (item->el_flags & ~NGQF_RW) | NGQF_WRITER;
3755 NG_NODE_REF(node); /* and one for the item */
3756 NGI_SET_NODE(item, node);
3757 if (hook) {
3758 NG_HOOK_REF(hook);
3759 NGI_SET_HOOK(item, hook);
3760 }
3761 NGI_FN2(item) = fn;
3762 NGI_ARG1(item) = arg1;
3763 NGI_ARG2(item) = arg2;
3764 return(ng_snd_item(item, flags));
3765 }
3766
3767 /*
3768 * Official timeout routines for Netgraph nodes.
3769 */
3770 static void
3771 ng_callout_trampoline(void *arg)
3772 {
3773 item_p item = arg;
3774
3775 CURVNET_SET(NGI_NODE(item)->nd_vnet);
3776 ng_snd_item(item, 0);
3777 CURVNET_RESTORE();
3778 }
3779
3780 int
3781 ng_callout(struct callout *c, node_p node, hook_p hook, int ticks,
3782 ng_item_fn *fn, void * arg1, int arg2)
3783 {
3784 item_p item, oitem;
3785
3786 if ((item = ng_alloc_item(NGQF_FN, NG_NOFLAGS)) == NULL)
3787 return (ENOMEM);
3788
3789 item->el_flags |= NGQF_WRITER;
3790 NG_NODE_REF(node); /* and one for the item */
3791 NGI_SET_NODE(item, node);
3792 if (hook) {
3793 NG_HOOK_REF(hook);
3794 NGI_SET_HOOK(item, hook);
3795 }
3796 NGI_FN(item) = fn;
3797 NGI_ARG1(item) = arg1;
3798 NGI_ARG2(item) = arg2;
3799 oitem = c->c_arg;
3800 if (callout_reset(c, ticks, &ng_callout_trampoline, item) == 1 &&
3801 oitem != NULL)
3802 NG_FREE_ITEM(oitem);
3803 return (0);
3804 }
3805
3806 /* A special modified version of untimeout() */
3807 int
3808 ng_uncallout(struct callout *c, node_p node)
3809 {
3810 item_p item;
3811 int rval;
3812
3813 KASSERT(c != NULL, ("ng_uncallout: NULL callout"));
3814 KASSERT(node != NULL, ("ng_uncallout: NULL node"));
3815
3816 rval = callout_stop(c);
3817 item = c->c_arg;
3818 /* Do an extra check */
3819 if ((rval > 0) && (c->c_func == &ng_callout_trampoline) &&
3820 (NGI_NODE(item) == node)) {
3821 /*
3822 * We successfully removed it from the queue before it ran
3823 * So now we need to unreference everything that was
3824 * given extra references. (NG_FREE_ITEM does this).
3825 */
3826 NG_FREE_ITEM(item);
3827 }
3828 c->c_arg = NULL;
3829
3830 return (rval);
3831 }
3832
3833 /*
3834 * Set the address, if none given, give the node here.
3835 */
3836 void
3837 ng_replace_retaddr(node_p here, item_p item, ng_ID_t retaddr)
3838 {
3839 if (retaddr) {
3840 NGI_RETADDR(item) = retaddr;
3841 } else {
3842 /*
3843 * The old return address should be ok.
3844 * If there isn't one, use the address here.
3845 */
3846 NGI_RETADDR(item) = ng_node2ID(here);
3847 }
3848 }
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