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 #include <vm/uma.h>
67
68 #include <net/netisr.h>
69 #include <net/vnet.h>
70
71 #include <netgraph/ng_message.h>
72 #include <netgraph/netgraph.h>
73 #include <netgraph/ng_parse.h>
74
75 MODULE_VERSION(netgraph, NG_ABI_VERSION);
76
77 /* Mutex to protect topology events. */
78 static struct rwlock ng_topo_lock;
79 #define TOPOLOGY_RLOCK() rw_rlock(&ng_topo_lock)
80 #define TOPOLOGY_RUNLOCK() rw_runlock(&ng_topo_lock)
81 #define TOPOLOGY_WLOCK() rw_wlock(&ng_topo_lock)
82 #define TOPOLOGY_WUNLOCK() rw_wunlock(&ng_topo_lock)
83 #define TOPOLOGY_NOTOWNED() rw_assert(&ng_topo_lock, RA_UNLOCKED)
84
85 #ifdef NETGRAPH_DEBUG
86 static struct mtx ng_nodelist_mtx; /* protects global node/hook lists */
87 static struct mtx ngq_mtx; /* protects the queue item list */
88
89 static SLIST_HEAD(, ng_node) ng_allnodes;
90 static LIST_HEAD(, ng_node) ng_freenodes; /* in debug, we never free() them */
91 static SLIST_HEAD(, ng_hook) ng_allhooks;
92 static LIST_HEAD(, ng_hook) ng_freehooks; /* in debug, we never free() them */
93
94 static void ng_dumpitems(void);
95 static void ng_dumpnodes(void);
96 static void ng_dumphooks(void);
97
98 #endif /* NETGRAPH_DEBUG */
99 /*
100 * DEAD versions of the structures.
101 * In order to avoid races, it is sometimes necessary to point
102 * at SOMETHING even though theoretically, the current entity is
103 * INVALID. Use these to avoid these races.
104 */
105 struct ng_type ng_deadtype = {
106 NG_ABI_VERSION,
107 "dead",
108 NULL, /* modevent */
109 NULL, /* constructor */
110 NULL, /* rcvmsg */
111 NULL, /* shutdown */
112 NULL, /* newhook */
113 NULL, /* findhook */
114 NULL, /* connect */
115 NULL, /* rcvdata */
116 NULL, /* disconnect */
117 NULL, /* cmdlist */
118 };
119
120 struct ng_node ng_deadnode = {
121 "dead",
122 &ng_deadtype,
123 NGF_INVALID,
124 0, /* numhooks */
125 NULL, /* private */
126 0, /* ID */
127 LIST_HEAD_INITIALIZER(ng_deadnode.nd_hooks),
128 {}, /* all_nodes list entry */
129 {}, /* id hashtable list entry */
130 { 0,
131 0,
132 {}, /* should never use! (should hang) */
133 {}, /* workqueue entry */
134 STAILQ_HEAD_INITIALIZER(ng_deadnode.nd_input_queue.queue),
135 },
136 1, /* refs */
137 NULL, /* vnet */
138 #ifdef NETGRAPH_DEBUG
139 ND_MAGIC,
140 __FILE__,
141 __LINE__,
142 {NULL}
143 #endif /* NETGRAPH_DEBUG */
144 };
145
146 struct ng_hook ng_deadhook = {
147 "dead",
148 NULL, /* private */
149 HK_INVALID | HK_DEAD,
150 0, /* undefined data link type */
151 &ng_deadhook, /* Peer is self */
152 &ng_deadnode, /* attached to deadnode */
153 {}, /* hooks list */
154 NULL, /* override rcvmsg() */
155 NULL, /* override rcvdata() */
156 1, /* refs always >= 1 */
157 #ifdef NETGRAPH_DEBUG
158 HK_MAGIC,
159 __FILE__,
160 __LINE__,
161 {NULL}
162 #endif /* NETGRAPH_DEBUG */
163 };
164
165 /*
166 * END DEAD STRUCTURES
167 */
168 /* List nodes with unallocated work */
169 static STAILQ_HEAD(, ng_node) ng_worklist = STAILQ_HEAD_INITIALIZER(ng_worklist);
170 static struct mtx ng_worklist_mtx; /* MUST LOCK NODE FIRST */
171
172 /* List of installed types */
173 static LIST_HEAD(, ng_type) ng_typelist;
174 static struct rwlock ng_typelist_lock;
175 #define TYPELIST_RLOCK() rw_rlock(&ng_typelist_lock)
176 #define TYPELIST_RUNLOCK() rw_runlock(&ng_typelist_lock)
177 #define TYPELIST_WLOCK() rw_wlock(&ng_typelist_lock)
178 #define TYPELIST_WUNLOCK() rw_wunlock(&ng_typelist_lock)
179
180 /* Hash related definitions. */
181 LIST_HEAD(nodehash, ng_node);
182 static VNET_DEFINE(struct nodehash *, ng_ID_hash);
183 static VNET_DEFINE(u_long, ng_ID_hmask);
184 static VNET_DEFINE(u_long, ng_nodes);
185 static VNET_DEFINE(struct nodehash *, ng_name_hash);
186 static VNET_DEFINE(u_long, ng_name_hmask);
187 static VNET_DEFINE(u_long, ng_named_nodes);
188 #define V_ng_ID_hash VNET(ng_ID_hash)
189 #define V_ng_ID_hmask VNET(ng_ID_hmask)
190 #define V_ng_nodes VNET(ng_nodes)
191 #define V_ng_name_hash VNET(ng_name_hash)
192 #define V_ng_name_hmask VNET(ng_name_hmask)
193 #define V_ng_named_nodes VNET(ng_named_nodes)
194
195 static struct rwlock ng_idhash_lock;
196 #define IDHASH_RLOCK() rw_rlock(&ng_idhash_lock)
197 #define IDHASH_RUNLOCK() rw_runlock(&ng_idhash_lock)
198 #define IDHASH_WLOCK() rw_wlock(&ng_idhash_lock)
199 #define IDHASH_WUNLOCK() rw_wunlock(&ng_idhash_lock)
200
201 /* Method to find a node.. used twice so do it here */
202 #define NG_IDHASH_FN(ID) ((ID) % (V_ng_ID_hmask + 1))
203 #define NG_IDHASH_FIND(ID, node) \
204 do { \
205 rw_assert(&ng_idhash_lock, RA_LOCKED); \
206 LIST_FOREACH(node, &V_ng_ID_hash[NG_IDHASH_FN(ID)], \
207 nd_idnodes) { \
208 if (NG_NODE_IS_VALID(node) \
209 && (NG_NODE_ID(node) == ID)) { \
210 break; \
211 } \
212 } \
213 } while (0)
214
215 static struct rwlock ng_namehash_lock;
216 #define NAMEHASH_RLOCK() rw_rlock(&ng_namehash_lock)
217 #define NAMEHASH_RUNLOCK() rw_runlock(&ng_namehash_lock)
218 #define NAMEHASH_WLOCK() rw_wlock(&ng_namehash_lock)
219 #define NAMEHASH_WUNLOCK() rw_wunlock(&ng_namehash_lock)
220
221 /* Internal functions */
222 static int ng_add_hook(node_p node, const char *name, hook_p * hookp);
223 static int ng_generic_msg(node_p here, item_p item, hook_p lasthook);
224 static ng_ID_t ng_decodeidname(const char *name);
225 static int ngb_mod_event(module_t mod, int event, void *data);
226 static void ng_worklist_add(node_p node);
227 static void ngthread(void *);
228 static int ng_apply_item(node_p node, item_p item, int rw);
229 static void ng_flush_input_queue(node_p node);
230 static node_p ng_ID2noderef(ng_ID_t ID);
231 static int ng_con_nodes(item_p item, node_p node, const char *name,
232 node_p node2, const char *name2);
233 static int ng_con_part2(node_p node, item_p item, hook_p hook);
234 static int ng_con_part3(node_p node, item_p item, hook_p hook);
235 static int ng_mkpeer(node_p node, const char *name, const char *name2,
236 char *type);
237 static void ng_name_rehash(void);
238 static void ng_ID_rehash(void);
239
240 /* Imported, these used to be externally visible, some may go back. */
241 void ng_destroy_hook(hook_p hook);
242 int ng_path2noderef(node_p here, const char *path,
243 node_p *dest, hook_p *lasthook);
244 int ng_make_node(const char *type, node_p *nodepp);
245 int ng_path_parse(char *addr, char **node, char **path, char **hook);
246 void ng_rmnode(node_p node, hook_p dummy1, void *dummy2, int dummy3);
247 void ng_unname(node_p node);
248
249 /* Our own netgraph malloc type */
250 MALLOC_DEFINE(M_NETGRAPH, "netgraph", "netgraph structures and ctrl messages");
251 MALLOC_DEFINE(M_NETGRAPH_MSG, "netgraph_msg", "netgraph name storage");
252 static MALLOC_DEFINE(M_NETGRAPH_HOOK, "netgraph_hook",
253 "netgraph hook structures");
254 static MALLOC_DEFINE(M_NETGRAPH_NODE, "netgraph_node",
255 "netgraph node structures");
256 static MALLOC_DEFINE(M_NETGRAPH_ITEM, "netgraph_item",
257 "netgraph item structures");
258
259 /* Should not be visible outside this file */
260
261 #define _NG_ALLOC_HOOK(hook) \
262 hook = malloc(sizeof(*hook), M_NETGRAPH_HOOK, M_NOWAIT | M_ZERO)
263 #define _NG_ALLOC_NODE(node) \
264 node = malloc(sizeof(*node), M_NETGRAPH_NODE, M_NOWAIT | M_ZERO)
265
266 #define NG_QUEUE_LOCK_INIT(n) \
267 mtx_init(&(n)->q_mtx, "ng_node", NULL, MTX_DEF)
268 #define NG_QUEUE_LOCK(n) \
269 mtx_lock(&(n)->q_mtx)
270 #define NG_QUEUE_UNLOCK(n) \
271 mtx_unlock(&(n)->q_mtx)
272 #define NG_WORKLIST_LOCK_INIT() \
273 mtx_init(&ng_worklist_mtx, "ng_worklist", NULL, MTX_DEF)
274 #define NG_WORKLIST_LOCK() \
275 mtx_lock(&ng_worklist_mtx)
276 #define NG_WORKLIST_UNLOCK() \
277 mtx_unlock(&ng_worklist_mtx)
278 #define NG_WORKLIST_SLEEP() \
279 mtx_sleep(&ng_worklist, &ng_worklist_mtx, PI_NET, "sleep", 0)
280 #define NG_WORKLIST_WAKEUP() \
281 wakeup_one(&ng_worklist)
282
283 #ifdef NETGRAPH_DEBUG /*----------------------------------------------*/
284 /*
285 * In debug mode:
286 * In an attempt to help track reference count screwups
287 * we do not free objects back to the malloc system, but keep them
288 * in a local cache where we can examine them and keep information safely
289 * after they have been freed.
290 * We use this scheme for nodes and hooks, and to some extent for items.
291 */
292 static __inline hook_p
293 ng_alloc_hook(void)
294 {
295 hook_p hook;
296 SLIST_ENTRY(ng_hook) temp;
297 mtx_lock(&ng_nodelist_mtx);
298 hook = LIST_FIRST(&ng_freehooks);
299 if (hook) {
300 LIST_REMOVE(hook, hk_hooks);
301 bcopy(&hook->hk_all, &temp, sizeof(temp));
302 bzero(hook, sizeof(struct ng_hook));
303 bcopy(&temp, &hook->hk_all, sizeof(temp));
304 mtx_unlock(&ng_nodelist_mtx);
305 hook->hk_magic = HK_MAGIC;
306 } else {
307 mtx_unlock(&ng_nodelist_mtx);
308 _NG_ALLOC_HOOK(hook);
309 if (hook) {
310 hook->hk_magic = HK_MAGIC;
311 mtx_lock(&ng_nodelist_mtx);
312 SLIST_INSERT_HEAD(&ng_allhooks, hook, hk_all);
313 mtx_unlock(&ng_nodelist_mtx);
314 }
315 }
316 return (hook);
317 }
318
319 static __inline node_p
320 ng_alloc_node(void)
321 {
322 node_p node;
323 SLIST_ENTRY(ng_node) temp;
324 mtx_lock(&ng_nodelist_mtx);
325 node = LIST_FIRST(&ng_freenodes);
326 if (node) {
327 LIST_REMOVE(node, nd_nodes);
328 bcopy(&node->nd_all, &temp, sizeof(temp));
329 bzero(node, sizeof(struct ng_node));
330 bcopy(&temp, &node->nd_all, sizeof(temp));
331 mtx_unlock(&ng_nodelist_mtx);
332 node->nd_magic = ND_MAGIC;
333 } else {
334 mtx_unlock(&ng_nodelist_mtx);
335 _NG_ALLOC_NODE(node);
336 if (node) {
337 node->nd_magic = ND_MAGIC;
338 mtx_lock(&ng_nodelist_mtx);
339 SLIST_INSERT_HEAD(&ng_allnodes, node, nd_all);
340 mtx_unlock(&ng_nodelist_mtx);
341 }
342 }
343 return (node);
344 }
345
346 #define NG_ALLOC_HOOK(hook) do { (hook) = ng_alloc_hook(); } while (0)
347 #define NG_ALLOC_NODE(node) do { (node) = ng_alloc_node(); } while (0)
348
349 #define NG_FREE_HOOK(hook) \
350 do { \
351 mtx_lock(&ng_nodelist_mtx); \
352 LIST_INSERT_HEAD(&ng_freehooks, hook, hk_hooks); \
353 hook->hk_magic = 0; \
354 mtx_unlock(&ng_nodelist_mtx); \
355 } while (0)
356
357 #define NG_FREE_NODE(node) \
358 do { \
359 mtx_lock(&ng_nodelist_mtx); \
360 LIST_INSERT_HEAD(&ng_freenodes, node, nd_nodes); \
361 node->nd_magic = 0; \
362 mtx_unlock(&ng_nodelist_mtx); \
363 } while (0)
364
365 #else /* NETGRAPH_DEBUG */ /*----------------------------------------------*/
366
367 #define NG_ALLOC_HOOK(hook) _NG_ALLOC_HOOK(hook)
368 #define NG_ALLOC_NODE(node) _NG_ALLOC_NODE(node)
369
370 #define NG_FREE_HOOK(hook) do { free((hook), M_NETGRAPH_HOOK); } while (0)
371 #define NG_FREE_NODE(node) do { free((node), M_NETGRAPH_NODE); } while (0)
372
373 #endif /* NETGRAPH_DEBUG */ /*----------------------------------------------*/
374
375 /* Set this to kdb_enter("X") to catch all errors as they occur */
376 #ifndef TRAP_ERROR
377 #define TRAP_ERROR()
378 #endif
379
380 static VNET_DEFINE(ng_ID_t, nextID) = 1;
381 #define V_nextID VNET(nextID)
382
383 #ifdef INVARIANTS
384 #define CHECK_DATA_MBUF(m) do { \
385 struct mbuf *n; \
386 int total; \
387 \
388 M_ASSERTPKTHDR(m); \
389 for (total = 0, n = (m); n != NULL; n = n->m_next) { \
390 total += n->m_len; \
391 if (n->m_nextpkt != NULL) \
392 panic("%s: m_nextpkt", __func__); \
393 } \
394 \
395 if ((m)->m_pkthdr.len != total) { \
396 panic("%s: %d != %d", \
397 __func__, (m)->m_pkthdr.len, total); \
398 } \
399 } while (0)
400 #else
401 #define CHECK_DATA_MBUF(m)
402 #endif
403
404 #define ERROUT(x) do { error = (x); goto done; } while (0)
405
406 /************************************************************************
407 Parse type definitions for generic messages
408 ************************************************************************/
409
410 /* Handy structure parse type defining macro */
411 #define DEFINE_PARSE_STRUCT_TYPE(lo, up, args) \
412 static const struct ng_parse_struct_field \
413 ng_ ## lo ## _type_fields[] = NG_GENERIC_ ## up ## _INFO args; \
414 static const struct ng_parse_type ng_generic_ ## lo ## _type = { \
415 &ng_parse_struct_type, \
416 &ng_ ## lo ## _type_fields \
417 }
418
419 DEFINE_PARSE_STRUCT_TYPE(mkpeer, MKPEER, ());
420 DEFINE_PARSE_STRUCT_TYPE(connect, CONNECT, ());
421 DEFINE_PARSE_STRUCT_TYPE(name, NAME, ());
422 DEFINE_PARSE_STRUCT_TYPE(rmhook, RMHOOK, ());
423 DEFINE_PARSE_STRUCT_TYPE(nodeinfo, NODEINFO, ());
424 DEFINE_PARSE_STRUCT_TYPE(typeinfo, TYPEINFO, ());
425 DEFINE_PARSE_STRUCT_TYPE(linkinfo, LINKINFO, (&ng_generic_nodeinfo_type));
426
427 /* Get length of an array when the length is stored as a 32 bit
428 value immediately preceding the array -- as with struct namelist
429 and struct typelist. */
430 static int
431 ng_generic_list_getLength(const struct ng_parse_type *type,
432 const u_char *start, const u_char *buf)
433 {
434 return *((const u_int32_t *)(buf - 4));
435 }
436
437 /* Get length of the array of struct linkinfo inside a struct hooklist */
438 static int
439 ng_generic_linkinfo_getLength(const struct ng_parse_type *type,
440 const u_char *start, const u_char *buf)
441 {
442 const struct hooklist *hl = (const struct hooklist *)start;
443
444 return hl->nodeinfo.hooks;
445 }
446
447 /* Array type for a variable length array of struct namelist */
448 static const struct ng_parse_array_info ng_nodeinfoarray_type_info = {
449 &ng_generic_nodeinfo_type,
450 &ng_generic_list_getLength
451 };
452 static const struct ng_parse_type ng_generic_nodeinfoarray_type = {
453 &ng_parse_array_type,
454 &ng_nodeinfoarray_type_info
455 };
456
457 /* Array type for a variable length array of struct typelist */
458 static const struct ng_parse_array_info ng_typeinfoarray_type_info = {
459 &ng_generic_typeinfo_type,
460 &ng_generic_list_getLength
461 };
462 static const struct ng_parse_type ng_generic_typeinfoarray_type = {
463 &ng_parse_array_type,
464 &ng_typeinfoarray_type_info
465 };
466
467 /* Array type for array of struct linkinfo in struct hooklist */
468 static const struct ng_parse_array_info ng_generic_linkinfo_array_type_info = {
469 &ng_generic_linkinfo_type,
470 &ng_generic_linkinfo_getLength
471 };
472 static const struct ng_parse_type ng_generic_linkinfo_array_type = {
473 &ng_parse_array_type,
474 &ng_generic_linkinfo_array_type_info
475 };
476
477 DEFINE_PARSE_STRUCT_TYPE(typelist, TYPELIST, (&ng_generic_typeinfoarray_type));
478 DEFINE_PARSE_STRUCT_TYPE(hooklist, HOOKLIST,
479 (&ng_generic_nodeinfo_type, &ng_generic_linkinfo_array_type));
480 DEFINE_PARSE_STRUCT_TYPE(listnodes, LISTNODES,
481 (&ng_generic_nodeinfoarray_type));
482
483 /* List of commands and how to convert arguments to/from ASCII */
484 static const struct ng_cmdlist ng_generic_cmds[] = {
485 {
486 NGM_GENERIC_COOKIE,
487 NGM_SHUTDOWN,
488 "shutdown",
489 NULL,
490 NULL
491 },
492 {
493 NGM_GENERIC_COOKIE,
494 NGM_MKPEER,
495 "mkpeer",
496 &ng_generic_mkpeer_type,
497 NULL
498 },
499 {
500 NGM_GENERIC_COOKIE,
501 NGM_CONNECT,
502 "connect",
503 &ng_generic_connect_type,
504 NULL
505 },
506 {
507 NGM_GENERIC_COOKIE,
508 NGM_NAME,
509 "name",
510 &ng_generic_name_type,
511 NULL
512 },
513 {
514 NGM_GENERIC_COOKIE,
515 NGM_RMHOOK,
516 "rmhook",
517 &ng_generic_rmhook_type,
518 NULL
519 },
520 {
521 NGM_GENERIC_COOKIE,
522 NGM_NODEINFO,
523 "nodeinfo",
524 NULL,
525 &ng_generic_nodeinfo_type
526 },
527 {
528 NGM_GENERIC_COOKIE,
529 NGM_LISTHOOKS,
530 "listhooks",
531 NULL,
532 &ng_generic_hooklist_type
533 },
534 {
535 NGM_GENERIC_COOKIE,
536 NGM_LISTNAMES,
537 "listnames",
538 NULL,
539 &ng_generic_listnodes_type /* same as NGM_LISTNODES */
540 },
541 {
542 NGM_GENERIC_COOKIE,
543 NGM_LISTNODES,
544 "listnodes",
545 NULL,
546 &ng_generic_listnodes_type
547 },
548 {
549 NGM_GENERIC_COOKIE,
550 NGM_LISTTYPES,
551 "listtypes",
552 NULL,
553 &ng_generic_typelist_type
554 },
555 {
556 NGM_GENERIC_COOKIE,
557 NGM_TEXT_CONFIG,
558 "textconfig",
559 NULL,
560 &ng_parse_string_type
561 },
562 {
563 NGM_GENERIC_COOKIE,
564 NGM_TEXT_STATUS,
565 "textstatus",
566 NULL,
567 &ng_parse_string_type
568 },
569 {
570 NGM_GENERIC_COOKIE,
571 NGM_ASCII2BINARY,
572 "ascii2binary",
573 &ng_parse_ng_mesg_type,
574 &ng_parse_ng_mesg_type
575 },
576 {
577 NGM_GENERIC_COOKIE,
578 NGM_BINARY2ASCII,
579 "binary2ascii",
580 &ng_parse_ng_mesg_type,
581 &ng_parse_ng_mesg_type
582 },
583 { 0 }
584 };
585
586 /************************************************************************
587 Node routines
588 ************************************************************************/
589
590 /*
591 * Instantiate a node of the requested type
592 */
593 int
594 ng_make_node(const char *typename, node_p *nodepp)
595 {
596 struct ng_type *type;
597 int error;
598
599 /* Check that the type makes sense */
600 if (typename == NULL) {
601 TRAP_ERROR();
602 return (EINVAL);
603 }
604
605 /* Locate the node type. If we fail we return. Do not try to load
606 * module.
607 */
608 if ((type = ng_findtype(typename)) == NULL)
609 return (ENXIO);
610
611 /*
612 * If we have a constructor, then make the node and
613 * call the constructor to do type specific initialisation.
614 */
615 if (type->constructor != NULL) {
616 if ((error = ng_make_node_common(type, nodepp)) == 0) {
617 if ((error = ((*type->constructor)(*nodepp))) != 0) {
618 NG_NODE_UNREF(*nodepp);
619 }
620 }
621 } else {
622 /*
623 * Node has no constructor. We cannot ask for one
624 * to be made. It must be brought into existence by
625 * some external agency. The external agency should
626 * call ng_make_node_common() directly to get the
627 * netgraph part initialised.
628 */
629 TRAP_ERROR();
630 error = EINVAL;
631 }
632 return (error);
633 }
634
635 /*
636 * Generic node creation. Called by node initialisation for externally
637 * instantiated nodes (e.g. hardware, sockets, etc ).
638 * The returned node has a reference count of 1.
639 */
640 int
641 ng_make_node_common(struct ng_type *type, node_p *nodepp)
642 {
643 node_p node;
644
645 /* Require the node type to have been already installed */
646 if (ng_findtype(type->name) == NULL) {
647 TRAP_ERROR();
648 return (EINVAL);
649 }
650
651 /* Make a node and try attach it to the type */
652 NG_ALLOC_NODE(node);
653 if (node == NULL) {
654 TRAP_ERROR();
655 return (ENOMEM);
656 }
657 node->nd_type = type;
658 #ifdef VIMAGE
659 node->nd_vnet = curvnet;
660 #endif
661 NG_NODE_REF(node); /* note reference */
662 type->refs++;
663
664 NG_QUEUE_LOCK_INIT(&node->nd_input_queue);
665 STAILQ_INIT(&node->nd_input_queue.queue);
666 node->nd_input_queue.q_flags = 0;
667
668 /* Initialize hook list for new node */
669 LIST_INIT(&node->nd_hooks);
670
671 /* Get an ID and put us in the hash chain. */
672 IDHASH_WLOCK();
673 for (;;) { /* wrap protection, even if silly */
674 node_p node2 = NULL;
675 node->nd_ID = V_nextID++; /* 137/sec for 1 year before wrap */
676
677 /* Is there a problem with the new number? */
678 NG_IDHASH_FIND(node->nd_ID, node2); /* already taken? */
679 if ((node->nd_ID != 0) && (node2 == NULL)) {
680 break;
681 }
682 }
683 V_ng_nodes++;
684 if (V_ng_nodes * 2 > V_ng_ID_hmask)
685 ng_ID_rehash();
686 LIST_INSERT_HEAD(&V_ng_ID_hash[NG_IDHASH_FN(node->nd_ID)], node,
687 nd_idnodes);
688 IDHASH_WUNLOCK();
689
690 /* Done */
691 *nodepp = node;
692 return (0);
693 }
694
695 /*
696 * Forceably start the shutdown process on a node. Either call
697 * its shutdown method, or do the default shutdown if there is
698 * no type-specific method.
699 *
700 * We can only be called from a shutdown message, so we know we have
701 * a writer lock, and therefore exclusive access. It also means
702 * that we should not be on the work queue, but we check anyhow.
703 *
704 * Persistent node types must have a type-specific method which
705 * allocates a new node in which case, this one is irretrievably going away,
706 * or cleans up anything it needs, and just makes the node valid again,
707 * in which case we allow the node to survive.
708 *
709 * XXX We need to think of how to tell a persistent node that we
710 * REALLY need to go away because the hardware has gone or we
711 * are rebooting.... etc.
712 */
713 void
714 ng_rmnode(node_p node, hook_p dummy1, void *dummy2, int dummy3)
715 {
716 hook_p hook;
717
718 /* Check if it's already shutting down */
719 if ((node->nd_flags & NGF_CLOSING) != 0)
720 return;
721
722 if (node == &ng_deadnode) {
723 printf ("shutdown called on deadnode\n");
724 return;
725 }
726
727 /* Add an extra reference so it doesn't go away during this */
728 NG_NODE_REF(node);
729
730 /*
731 * Mark it invalid so any newcomers know not to try use it
732 * Also add our own mark so we can't recurse
733 * note that NGF_INVALID does not do this as it's also set during
734 * creation
735 */
736 node->nd_flags |= NGF_INVALID|NGF_CLOSING;
737
738 /* If node has its pre-shutdown method, then call it first*/
739 if (node->nd_type && node->nd_type->close)
740 (*node->nd_type->close)(node);
741
742 /* Notify all remaining connected nodes to disconnect */
743 while ((hook = LIST_FIRST(&node->nd_hooks)) != NULL)
744 ng_destroy_hook(hook);
745
746 /*
747 * Drain the input queue forceably.
748 * it has no hooks so what's it going to do, bleed on someone?
749 * Theoretically we came here from a queue entry that was added
750 * Just before the queue was closed, so it should be empty anyway.
751 * Also removes us from worklist if needed.
752 */
753 ng_flush_input_queue(node);
754
755 /* Ask the type if it has anything to do in this case */
756 if (node->nd_type && node->nd_type->shutdown) {
757 (*node->nd_type->shutdown)(node);
758 if (NG_NODE_IS_VALID(node)) {
759 /*
760 * Well, blow me down if the node code hasn't declared
761 * that it doesn't want to die.
762 * Presumably it is a persistent node.
763 * If we REALLY want it to go away,
764 * e.g. hardware going away,
765 * Our caller should set NGF_REALLY_DIE in nd_flags.
766 */
767 node->nd_flags &= ~(NGF_INVALID|NGF_CLOSING);
768 NG_NODE_UNREF(node); /* Assume they still have theirs */
769 return;
770 }
771 } else { /* do the default thing */
772 NG_NODE_UNREF(node);
773 }
774
775 ng_unname(node); /* basically a NOP these days */
776
777 /*
778 * Remove extra reference, possibly the last
779 * Possible other holders of references may include
780 * timeout callouts, but theoretically the node's supposed to
781 * have cancelled them. Possibly hardware dependencies may
782 * force a driver to 'linger' with a reference.
783 */
784 NG_NODE_UNREF(node);
785 }
786
787 /*
788 * Remove a reference to the node, possibly the last.
789 * deadnode always acts as it it were the last.
790 */
791 void
792 ng_unref_node(node_p node)
793 {
794
795 if (node == &ng_deadnode)
796 return;
797
798 CURVNET_SET(node->nd_vnet);
799
800 if (refcount_release(&node->nd_refs)) { /* we were the last */
801
802 node->nd_type->refs--; /* XXX maybe should get types lock? */
803 NAMEHASH_WLOCK();
804 if (NG_NODE_HAS_NAME(node)) {
805 V_ng_named_nodes--;
806 LIST_REMOVE(node, nd_nodes);
807 }
808 NAMEHASH_WUNLOCK();
809
810 IDHASH_WLOCK();
811 V_ng_nodes--;
812 LIST_REMOVE(node, nd_idnodes);
813 IDHASH_WUNLOCK();
814
815 mtx_destroy(&node->nd_input_queue.q_mtx);
816 NG_FREE_NODE(node);
817 }
818 CURVNET_RESTORE();
819 }
820
821 /************************************************************************
822 Node ID handling
823 ************************************************************************/
824 static node_p
825 ng_ID2noderef(ng_ID_t ID)
826 {
827 node_p node;
828
829 IDHASH_RLOCK();
830 NG_IDHASH_FIND(ID, node);
831 if (node)
832 NG_NODE_REF(node);
833 IDHASH_RUNLOCK();
834 return(node);
835 }
836
837 ng_ID_t
838 ng_node2ID(node_p node)
839 {
840 return (node ? NG_NODE_ID(node) : 0);
841 }
842
843 /************************************************************************
844 Node name handling
845 ************************************************************************/
846
847 /*
848 * Assign a node a name.
849 */
850 int
851 ng_name_node(node_p node, const char *name)
852 {
853 uint32_t hash;
854 node_p node2;
855 int i;
856
857 /* Rename without change is a noop */
858 if (strcmp(NG_NODE_NAME(node), name) == 0)
859 return (0);
860
861 /* Check the name is valid */
862 for (i = 0; i < NG_NODESIZ; i++) {
863 if (name[i] == '\0' || name[i] == '.' || name[i] == ':')
864 break;
865 }
866 if (i == 0 || name[i] != '\0') {
867 TRAP_ERROR();
868 return (EINVAL);
869 }
870 if (ng_decodeidname(name) != 0) { /* valid IDs not allowed here */
871 TRAP_ERROR();
872 return (EINVAL);
873 }
874
875 NAMEHASH_WLOCK();
876 if (V_ng_named_nodes * 2 > V_ng_name_hmask)
877 ng_name_rehash();
878
879 hash = hash32_str(name, HASHINIT) & V_ng_name_hmask;
880 /* Check the name isn't already being used. */
881 LIST_FOREACH(node2, &V_ng_name_hash[hash], nd_nodes)
882 if (NG_NODE_IS_VALID(node2) &&
883 (strcmp(NG_NODE_NAME(node2), name) == 0)) {
884 NAMEHASH_WUNLOCK();
885 return (EADDRINUSE);
886 }
887
888 if (NG_NODE_HAS_NAME(node))
889 LIST_REMOVE(node, nd_nodes);
890 else
891 V_ng_named_nodes++;
892 /* Copy it. */
893 strlcpy(NG_NODE_NAME(node), name, NG_NODESIZ);
894 /* Update name hash. */
895 LIST_INSERT_HEAD(&V_ng_name_hash[hash], node, nd_nodes);
896 NAMEHASH_WUNLOCK();
897
898 return (0);
899 }
900
901 /*
902 * Find a node by absolute name. The name should NOT end with ':'
903 * The name "." means "this node" and "[xxx]" means "the node
904 * with ID (ie, at address) xxx".
905 *
906 * Returns the node if found, else NULL.
907 * Eventually should add something faster than a sequential search.
908 * Note it acquires a reference on the node so you can be sure it's still
909 * there.
910 */
911 node_p
912 ng_name2noderef(node_p here, const char *name)
913 {
914 node_p node;
915 ng_ID_t temp;
916 int hash;
917
918 /* "." means "this node" */
919 if (strcmp(name, ".") == 0) {
920 NG_NODE_REF(here);
921 return(here);
922 }
923
924 /* Check for name-by-ID */
925 if ((temp = ng_decodeidname(name)) != 0) {
926 return (ng_ID2noderef(temp));
927 }
928
929 /* Find node by name. */
930 hash = hash32_str(name, HASHINIT) & V_ng_name_hmask;
931 NAMEHASH_RLOCK();
932 LIST_FOREACH(node, &V_ng_name_hash[hash], nd_nodes)
933 if (NG_NODE_IS_VALID(node) &&
934 (strcmp(NG_NODE_NAME(node), name) == 0)) {
935 NG_NODE_REF(node);
936 break;
937 }
938 NAMEHASH_RUNLOCK();
939
940 return (node);
941 }
942
943 /*
944 * Decode an ID name, eg. "[f03034de]". Returns 0 if the
945 * string is not valid, otherwise returns the value.
946 */
947 static ng_ID_t
948 ng_decodeidname(const char *name)
949 {
950 const int len = strlen(name);
951 char *eptr;
952 u_long val;
953
954 /* Check for proper length, brackets, no leading junk */
955 if ((len < 3) || (name[0] != '[') || (name[len - 1] != ']') ||
956 (!isxdigit(name[1])))
957 return ((ng_ID_t)0);
958
959 /* Decode number */
960 val = strtoul(name + 1, &eptr, 16);
961 if ((eptr - name != len - 1) || (val == ULONG_MAX) || (val == 0))
962 return ((ng_ID_t)0);
963
964 return ((ng_ID_t)val);
965 }
966
967 /*
968 * Remove a name from a node. This should only be called
969 * when shutting down and removing the node.
970 */
971 void
972 ng_unname(node_p node)
973 {
974 }
975
976 /*
977 * Allocate a bigger name hash.
978 */
979 static void
980 ng_name_rehash()
981 {
982 struct nodehash *new;
983 uint32_t hash;
984 u_long hmask;
985 node_p node, node2;
986 int i;
987
988 new = hashinit_flags((V_ng_name_hmask + 1) * 2, M_NETGRAPH_NODE, &hmask,
989 HASH_NOWAIT);
990 if (new == NULL)
991 return;
992
993 for (i = 0; i <= V_ng_name_hmask; i++)
994 LIST_FOREACH_SAFE(node, &V_ng_name_hash[i], nd_nodes, node2) {
995 #ifdef INVARIANTS
996 LIST_REMOVE(node, nd_nodes);
997 #endif
998 hash = hash32_str(NG_NODE_NAME(node), HASHINIT) & hmask;
999 LIST_INSERT_HEAD(&new[hash], node, nd_nodes);
1000 }
1001
1002 hashdestroy(V_ng_name_hash, M_NETGRAPH_NODE, V_ng_name_hmask);
1003 V_ng_name_hash = new;
1004 V_ng_name_hmask = hmask;
1005 }
1006
1007 /*
1008 * Allocate a bigger ID hash.
1009 */
1010 static void
1011 ng_ID_rehash()
1012 {
1013 struct nodehash *new;
1014 uint32_t hash;
1015 u_long hmask;
1016 node_p node, node2;
1017 int i;
1018
1019 new = hashinit_flags((V_ng_ID_hmask + 1) * 2, M_NETGRAPH_NODE, &hmask,
1020 HASH_NOWAIT);
1021 if (new == NULL)
1022 return;
1023
1024 for (i = 0; i <= V_ng_ID_hmask; i++)
1025 LIST_FOREACH_SAFE(node, &V_ng_ID_hash[i], nd_idnodes, node2) {
1026 #ifdef INVARIANTS
1027 LIST_REMOVE(node, nd_idnodes);
1028 #endif
1029 hash = (node->nd_ID % (hmask + 1));
1030 LIST_INSERT_HEAD(&new[hash], node, nd_idnodes);
1031 }
1032
1033 hashdestroy(V_ng_ID_hash, M_NETGRAPH_NODE, V_ng_name_hmask);
1034 V_ng_ID_hash = new;
1035 V_ng_ID_hmask = hmask;
1036 }
1037
1038 /************************************************************************
1039 Hook routines
1040 Names are not optional. Hooks are always connected, except for a
1041 brief moment within these routines. On invalidation or during creation
1042 they are connected to the 'dead' hook.
1043 ************************************************************************/
1044
1045 /*
1046 * Remove a hook reference
1047 */
1048 void
1049 ng_unref_hook(hook_p hook)
1050 {
1051
1052 if (hook == &ng_deadhook)
1053 return;
1054
1055 if (refcount_release(&hook->hk_refs)) { /* we were the last */
1056 if (_NG_HOOK_NODE(hook)) /* it'll probably be ng_deadnode */
1057 _NG_NODE_UNREF((_NG_HOOK_NODE(hook)));
1058 NG_FREE_HOOK(hook);
1059 }
1060 }
1061
1062 /*
1063 * Add an unconnected hook to a node. Only used internally.
1064 * Assumes node is locked. (XXX not yet true )
1065 */
1066 static int
1067 ng_add_hook(node_p node, const char *name, hook_p *hookp)
1068 {
1069 hook_p hook;
1070 int error = 0;
1071
1072 /* Check that the given name is good */
1073 if (name == NULL) {
1074 TRAP_ERROR();
1075 return (EINVAL);
1076 }
1077 if (ng_findhook(node, name) != NULL) {
1078 TRAP_ERROR();
1079 return (EEXIST);
1080 }
1081
1082 /* Allocate the hook and link it up */
1083 NG_ALLOC_HOOK(hook);
1084 if (hook == NULL) {
1085 TRAP_ERROR();
1086 return (ENOMEM);
1087 }
1088 hook->hk_refs = 1; /* add a reference for us to return */
1089 hook->hk_flags = HK_INVALID;
1090 hook->hk_peer = &ng_deadhook; /* start off this way */
1091 hook->hk_node = node;
1092 NG_NODE_REF(node); /* each hook counts as a reference */
1093
1094 /* Set hook name */
1095 strlcpy(NG_HOOK_NAME(hook), name, NG_HOOKSIZ);
1096
1097 /*
1098 * Check if the node type code has something to say about it
1099 * If it fails, the unref of the hook will also unref the node.
1100 */
1101 if (node->nd_type->newhook != NULL) {
1102 if ((error = (*node->nd_type->newhook)(node, hook, name))) {
1103 NG_HOOK_UNREF(hook); /* this frees the hook */
1104 return (error);
1105 }
1106 }
1107 /*
1108 * The 'type' agrees so far, so go ahead and link it in.
1109 * We'll ask again later when we actually connect the hooks.
1110 */
1111 LIST_INSERT_HEAD(&node->nd_hooks, hook, hk_hooks);
1112 node->nd_numhooks++;
1113 NG_HOOK_REF(hook); /* one for the node */
1114
1115 if (hookp)
1116 *hookp = hook;
1117 return (0);
1118 }
1119
1120 /*
1121 * Find a hook
1122 *
1123 * Node types may supply their own optimized routines for finding
1124 * hooks. If none is supplied, we just do a linear search.
1125 * XXX Possibly we should add a reference to the hook?
1126 */
1127 hook_p
1128 ng_findhook(node_p node, const char *name)
1129 {
1130 hook_p hook;
1131
1132 if (node->nd_type->findhook != NULL)
1133 return (*node->nd_type->findhook)(node, name);
1134 LIST_FOREACH(hook, &node->nd_hooks, hk_hooks) {
1135 if (NG_HOOK_IS_VALID(hook) &&
1136 (strcmp(NG_HOOK_NAME(hook), name) == 0))
1137 return (hook);
1138 }
1139 return (NULL);
1140 }
1141
1142 /*
1143 * Destroy a hook
1144 *
1145 * As hooks are always attached, this really destroys two hooks.
1146 * The one given, and the one attached to it. Disconnect the hooks
1147 * from each other first. We reconnect the peer hook to the 'dead'
1148 * hook so that it can still exist after we depart. We then
1149 * send the peer its own destroy message. This ensures that we only
1150 * interact with the peer's structures when it is locked processing that
1151 * message. We hold a reference to the peer hook so we are guaranteed that
1152 * the peer hook and node are still going to exist until
1153 * we are finished there as the hook holds a ref on the node.
1154 * We run this same code again on the peer hook, but that time it is already
1155 * attached to the 'dead' hook.
1156 *
1157 * This routine is called at all stages of hook creation
1158 * on error detection and must be able to handle any such stage.
1159 */
1160 void
1161 ng_destroy_hook(hook_p hook)
1162 {
1163 hook_p peer;
1164 node_p node;
1165
1166 if (hook == &ng_deadhook) { /* better safe than sorry */
1167 printf("ng_destroy_hook called on deadhook\n");
1168 return;
1169 }
1170
1171 /*
1172 * Protect divorce process with mutex, to avoid races on
1173 * simultaneous disconnect.
1174 */
1175 TOPOLOGY_WLOCK();
1176
1177 hook->hk_flags |= HK_INVALID;
1178
1179 peer = NG_HOOK_PEER(hook);
1180 node = NG_HOOK_NODE(hook);
1181
1182 if (peer && (peer != &ng_deadhook)) {
1183 /*
1184 * Set the peer to point to ng_deadhook
1185 * from this moment on we are effectively independent it.
1186 * send it an rmhook message of it's own.
1187 */
1188 peer->hk_peer = &ng_deadhook; /* They no longer know us */
1189 hook->hk_peer = &ng_deadhook; /* Nor us, them */
1190 if (NG_HOOK_NODE(peer) == &ng_deadnode) {
1191 /*
1192 * If it's already divorced from a node,
1193 * just free it.
1194 */
1195 TOPOLOGY_WUNLOCK();
1196 } else {
1197 TOPOLOGY_WUNLOCK();
1198 ng_rmhook_self(peer); /* Send it a surprise */
1199 }
1200 NG_HOOK_UNREF(peer); /* account for peer link */
1201 NG_HOOK_UNREF(hook); /* account for peer link */
1202 } else
1203 TOPOLOGY_WUNLOCK();
1204
1205 TOPOLOGY_NOTOWNED();
1206
1207 /*
1208 * Remove the hook from the node's list to avoid possible recursion
1209 * in case the disconnection results in node shutdown.
1210 */
1211 if (node == &ng_deadnode) { /* happens if called from ng_con_nodes() */
1212 return;
1213 }
1214 LIST_REMOVE(hook, hk_hooks);
1215 node->nd_numhooks--;
1216 if (node->nd_type->disconnect) {
1217 /*
1218 * The type handler may elect to destroy the node so don't
1219 * trust its existence after this point. (except
1220 * that we still hold a reference on it. (which we
1221 * inherrited from the hook we are destroying)
1222 */
1223 (*node->nd_type->disconnect) (hook);
1224 }
1225
1226 /*
1227 * Note that because we will point to ng_deadnode, the original node
1228 * is not decremented automatically so we do that manually.
1229 */
1230 _NG_HOOK_NODE(hook) = &ng_deadnode;
1231 NG_NODE_UNREF(node); /* We no longer point to it so adjust count */
1232 NG_HOOK_UNREF(hook); /* Account for linkage (in list) to node */
1233 }
1234
1235 /*
1236 * Take two hooks on a node and merge the connection so that the given node
1237 * is effectively bypassed.
1238 */
1239 int
1240 ng_bypass(hook_p hook1, hook_p hook2)
1241 {
1242 if (hook1->hk_node != hook2->hk_node) {
1243 TRAP_ERROR();
1244 return (EINVAL);
1245 }
1246 TOPOLOGY_WLOCK();
1247 if (NG_HOOK_NOT_VALID(hook1) || NG_HOOK_NOT_VALID(hook2)) {
1248 TOPOLOGY_WUNLOCK();
1249 return (EINVAL);
1250 }
1251 hook1->hk_peer->hk_peer = hook2->hk_peer;
1252 hook2->hk_peer->hk_peer = hook1->hk_peer;
1253
1254 hook1->hk_peer = &ng_deadhook;
1255 hook2->hk_peer = &ng_deadhook;
1256 TOPOLOGY_WUNLOCK();
1257
1258 NG_HOOK_UNREF(hook1);
1259 NG_HOOK_UNREF(hook2);
1260
1261 /* XXX If we ever cache methods on hooks update them as well */
1262 ng_destroy_hook(hook1);
1263 ng_destroy_hook(hook2);
1264 return (0);
1265 }
1266
1267 /*
1268 * Install a new netgraph type
1269 */
1270 int
1271 ng_newtype(struct ng_type *tp)
1272 {
1273 const size_t namelen = strlen(tp->name);
1274
1275 /* Check version and type name fields */
1276 if ((tp->version != NG_ABI_VERSION) || (namelen == 0) ||
1277 (namelen >= NG_TYPESIZ)) {
1278 TRAP_ERROR();
1279 if (tp->version != NG_ABI_VERSION) {
1280 printf("Netgraph: Node type rejected. ABI mismatch. "
1281 "Suggest recompile\n");
1282 }
1283 return (EINVAL);
1284 }
1285
1286 /* Check for name collision */
1287 if (ng_findtype(tp->name) != NULL) {
1288 TRAP_ERROR();
1289 return (EEXIST);
1290 }
1291
1292 /* Link in new type */
1293 TYPELIST_WLOCK();
1294 LIST_INSERT_HEAD(&ng_typelist, tp, types);
1295 tp->refs = 1; /* first ref is linked list */
1296 TYPELIST_WUNLOCK();
1297 return (0);
1298 }
1299
1300 /*
1301 * unlink a netgraph type
1302 * If no examples exist
1303 */
1304 int
1305 ng_rmtype(struct ng_type *tp)
1306 {
1307 /* Check for name collision */
1308 if (tp->refs != 1) {
1309 TRAP_ERROR();
1310 return (EBUSY);
1311 }
1312
1313 /* Unlink type */
1314 TYPELIST_WLOCK();
1315 LIST_REMOVE(tp, types);
1316 TYPELIST_WUNLOCK();
1317 return (0);
1318 }
1319
1320 /*
1321 * Look for a type of the name given
1322 */
1323 struct ng_type *
1324 ng_findtype(const char *typename)
1325 {
1326 struct ng_type *type;
1327
1328 TYPELIST_RLOCK();
1329 LIST_FOREACH(type, &ng_typelist, types) {
1330 if (strcmp(type->name, typename) == 0)
1331 break;
1332 }
1333 TYPELIST_RUNLOCK();
1334 return (type);
1335 }
1336
1337 /************************************************************************
1338 Composite routines
1339 ************************************************************************/
1340 /*
1341 * Connect two nodes using the specified hooks, using queued functions.
1342 */
1343 static int
1344 ng_con_part3(node_p node, item_p item, hook_p hook)
1345 {
1346 int error = 0;
1347
1348 /*
1349 * When we run, we know that the node 'node' is locked for us.
1350 * Our caller has a reference on the hook.
1351 * Our caller has a reference on the node.
1352 * (In this case our caller is ng_apply_item() ).
1353 * The peer hook has a reference on the hook.
1354 * We are all set up except for the final call to the node, and
1355 * the clearing of the INVALID flag.
1356 */
1357 if (NG_HOOK_NODE(hook) == &ng_deadnode) {
1358 /*
1359 * The node must have been freed again since we last visited
1360 * here. ng_destry_hook() has this effect but nothing else does.
1361 * We should just release our references and
1362 * free anything we can think of.
1363 * Since we know it's been destroyed, and it's our caller
1364 * that holds the references, just return.
1365 */
1366 ERROUT(ENOENT);
1367 }
1368 if (hook->hk_node->nd_type->connect) {
1369 if ((error = (*hook->hk_node->nd_type->connect) (hook))) {
1370 ng_destroy_hook(hook); /* also zaps peer */
1371 printf("failed in ng_con_part3()\n");
1372 ERROUT(error);
1373 }
1374 }
1375 /*
1376 * XXX this is wrong for SMP. Possibly we need
1377 * to separate out 'create' and 'invalid' flags.
1378 * should only set flags on hooks we have locked under our node.
1379 */
1380 hook->hk_flags &= ~HK_INVALID;
1381 done:
1382 NG_FREE_ITEM(item);
1383 return (error);
1384 }
1385
1386 static int
1387 ng_con_part2(node_p node, item_p item, hook_p hook)
1388 {
1389 hook_p peer;
1390 int error = 0;
1391
1392 /*
1393 * When we run, we know that the node 'node' is locked for us.
1394 * Our caller has a reference on the hook.
1395 * Our caller has a reference on the node.
1396 * (In this case our caller is ng_apply_item() ).
1397 * The peer hook has a reference on the hook.
1398 * our node pointer points to the 'dead' node.
1399 * First check the hook name is unique.
1400 * Should not happen because we checked before queueing this.
1401 */
1402 if (ng_findhook(node, NG_HOOK_NAME(hook)) != NULL) {
1403 TRAP_ERROR();
1404 ng_destroy_hook(hook); /* should destroy peer too */
1405 printf("failed in ng_con_part2()\n");
1406 ERROUT(EEXIST);
1407 }
1408 /*
1409 * Check if the node type code has something to say about it
1410 * If it fails, the unref of the hook will also unref the attached node,
1411 * however since that node is 'ng_deadnode' this will do nothing.
1412 * The peer hook will also be destroyed.
1413 */
1414 if (node->nd_type->newhook != NULL) {
1415 if ((error = (*node->nd_type->newhook)(node, hook,
1416 hook->hk_name))) {
1417 ng_destroy_hook(hook); /* should destroy peer too */
1418 printf("failed in ng_con_part2()\n");
1419 ERROUT(error);
1420 }
1421 }
1422
1423 /*
1424 * The 'type' agrees so far, so go ahead and link it in.
1425 * We'll ask again later when we actually connect the hooks.
1426 */
1427 hook->hk_node = node; /* just overwrite ng_deadnode */
1428 NG_NODE_REF(node); /* each hook counts as a reference */
1429 LIST_INSERT_HEAD(&node->nd_hooks, hook, hk_hooks);
1430 node->nd_numhooks++;
1431 NG_HOOK_REF(hook); /* one for the node */
1432
1433 /*
1434 * We now have a symmetrical situation, where both hooks have been
1435 * linked to their nodes, the newhook methods have been called
1436 * And the references are all correct. The hooks are still marked
1437 * as invalid, as we have not called the 'connect' methods
1438 * yet.
1439 * We can call the local one immediately as we have the
1440 * node locked, but we need to queue the remote one.
1441 */
1442 if (hook->hk_node->nd_type->connect) {
1443 if ((error = (*hook->hk_node->nd_type->connect) (hook))) {
1444 ng_destroy_hook(hook); /* also zaps peer */
1445 printf("failed in ng_con_part2(A)\n");
1446 ERROUT(error);
1447 }
1448 }
1449
1450 /*
1451 * Acquire topo mutex to avoid race with ng_destroy_hook().
1452 */
1453 TOPOLOGY_RLOCK();
1454 peer = hook->hk_peer;
1455 if (peer == &ng_deadhook) {
1456 TOPOLOGY_RUNLOCK();
1457 printf("failed in ng_con_part2(B)\n");
1458 ng_destroy_hook(hook);
1459 ERROUT(ENOENT);
1460 }
1461 TOPOLOGY_RUNLOCK();
1462
1463 if ((error = ng_send_fn2(peer->hk_node, peer, item, &ng_con_part3,
1464 NULL, 0, NG_REUSE_ITEM))) {
1465 printf("failed in ng_con_part2(C)\n");
1466 ng_destroy_hook(hook); /* also zaps peer */
1467 return (error); /* item was consumed. */
1468 }
1469 hook->hk_flags &= ~HK_INVALID; /* need both to be able to work */
1470 return (0); /* item was consumed. */
1471 done:
1472 NG_FREE_ITEM(item);
1473 return (error);
1474 }
1475
1476 /*
1477 * Connect this node with another node. We assume that this node is
1478 * currently locked, as we are only called from an NGM_CONNECT message.
1479 */
1480 static int
1481 ng_con_nodes(item_p item, node_p node, const char *name,
1482 node_p node2, const char *name2)
1483 {
1484 int error;
1485 hook_p hook;
1486 hook_p hook2;
1487
1488 if (ng_findhook(node2, name2) != NULL) {
1489 return(EEXIST);
1490 }
1491 if ((error = ng_add_hook(node, name, &hook))) /* gives us a ref */
1492 return (error);
1493 /* Allocate the other hook and link it up */
1494 NG_ALLOC_HOOK(hook2);
1495 if (hook2 == NULL) {
1496 TRAP_ERROR();
1497 ng_destroy_hook(hook); /* XXX check ref counts so far */
1498 NG_HOOK_UNREF(hook); /* including our ref */
1499 return (ENOMEM);
1500 }
1501 hook2->hk_refs = 1; /* start with a reference for us. */
1502 hook2->hk_flags = HK_INVALID;
1503 hook2->hk_peer = hook; /* Link the two together */
1504 hook->hk_peer = hook2;
1505 NG_HOOK_REF(hook); /* Add a ref for the peer to each*/
1506 NG_HOOK_REF(hook2);
1507 hook2->hk_node = &ng_deadnode;
1508 strlcpy(NG_HOOK_NAME(hook2), name2, NG_HOOKSIZ);
1509
1510 /*
1511 * Queue the function above.
1512 * Procesing continues in that function in the lock context of
1513 * the other node.
1514 */
1515 if ((error = ng_send_fn2(node2, hook2, item, &ng_con_part2, NULL, 0,
1516 NG_NOFLAGS))) {
1517 printf("failed in ng_con_nodes(): %d\n", error);
1518 ng_destroy_hook(hook); /* also zaps peer */
1519 }
1520
1521 NG_HOOK_UNREF(hook); /* Let each hook go if it wants to */
1522 NG_HOOK_UNREF(hook2);
1523 return (error);
1524 }
1525
1526 /*
1527 * Make a peer and connect.
1528 * We assume that the local node is locked.
1529 * The new node probably doesn't need a lock until
1530 * it has a hook, because it cannot really have any work until then,
1531 * but we should think about it a bit more.
1532 *
1533 * The problem may come if the other node also fires up
1534 * some hardware or a timer or some other source of activation,
1535 * also it may already get a command msg via it's ID.
1536 *
1537 * We could use the same method as ng_con_nodes() but we'd have
1538 * to add ability to remove the node when failing. (Not hard, just
1539 * make arg1 point to the node to remove).
1540 * Unless of course we just ignore failure to connect and leave
1541 * an unconnected node?
1542 */
1543 static int
1544 ng_mkpeer(node_p node, const char *name, const char *name2, char *type)
1545 {
1546 node_p node2;
1547 hook_p hook1, hook2;
1548 int error;
1549
1550 if ((error = ng_make_node(type, &node2))) {
1551 return (error);
1552 }
1553
1554 if ((error = ng_add_hook(node, name, &hook1))) { /* gives us a ref */
1555 ng_rmnode(node2, NULL, NULL, 0);
1556 return (error);
1557 }
1558
1559 if ((error = ng_add_hook(node2, name2, &hook2))) {
1560 ng_rmnode(node2, NULL, NULL, 0);
1561 ng_destroy_hook(hook1);
1562 NG_HOOK_UNREF(hook1);
1563 return (error);
1564 }
1565
1566 /*
1567 * Actually link the two hooks together.
1568 */
1569 hook1->hk_peer = hook2;
1570 hook2->hk_peer = hook1;
1571
1572 /* Each hook is referenced by the other */
1573 NG_HOOK_REF(hook1);
1574 NG_HOOK_REF(hook2);
1575
1576 /* Give each node the opportunity to veto the pending connection */
1577 if (hook1->hk_node->nd_type->connect) {
1578 error = (*hook1->hk_node->nd_type->connect) (hook1);
1579 }
1580
1581 if ((error == 0) && hook2->hk_node->nd_type->connect) {
1582 error = (*hook2->hk_node->nd_type->connect) (hook2);
1583
1584 }
1585
1586 /*
1587 * drop the references we were holding on the two hooks.
1588 */
1589 if (error) {
1590 ng_destroy_hook(hook2); /* also zaps hook1 */
1591 ng_rmnode(node2, NULL, NULL, 0);
1592 } else {
1593 /* As a last act, allow the hooks to be used */
1594 hook1->hk_flags &= ~HK_INVALID;
1595 hook2->hk_flags &= ~HK_INVALID;
1596 }
1597 NG_HOOK_UNREF(hook1);
1598 NG_HOOK_UNREF(hook2);
1599 return (error);
1600 }
1601
1602 /************************************************************************
1603 Utility routines to send self messages
1604 ************************************************************************/
1605
1606 /* Shut this node down as soon as everyone is clear of it */
1607 /* Should add arg "immediately" to jump the queue */
1608 int
1609 ng_rmnode_self(node_p node)
1610 {
1611 int error;
1612
1613 if (node == &ng_deadnode)
1614 return (0);
1615 node->nd_flags |= NGF_INVALID;
1616 if (node->nd_flags & NGF_CLOSING)
1617 return (0);
1618
1619 error = ng_send_fn(node, NULL, &ng_rmnode, NULL, 0);
1620 return (error);
1621 }
1622
1623 static void
1624 ng_rmhook_part2(node_p node, hook_p hook, void *arg1, int arg2)
1625 {
1626 ng_destroy_hook(hook);
1627 return ;
1628 }
1629
1630 int
1631 ng_rmhook_self(hook_p hook)
1632 {
1633 int error;
1634 node_p node = NG_HOOK_NODE(hook);
1635
1636 if (node == &ng_deadnode)
1637 return (0);
1638
1639 error = ng_send_fn(node, hook, &ng_rmhook_part2, NULL, 0);
1640 return (error);
1641 }
1642
1643 /***********************************************************************
1644 * Parse and verify a string of the form: <NODE:><PATH>
1645 *
1646 * Such a string can refer to a specific node or a specific hook
1647 * on a specific node, depending on how you look at it. In the
1648 * latter case, the PATH component must not end in a dot.
1649 *
1650 * Both <NODE:> and <PATH> are optional. The <PATH> is a string
1651 * of hook names separated by dots. This breaks out the original
1652 * string, setting *nodep to "NODE" (or NULL if none) and *pathp
1653 * to "PATH" (or NULL if degenerate). Also, *hookp will point to
1654 * the final hook component of <PATH>, if any, otherwise NULL.
1655 *
1656 * This returns -1 if the path is malformed. The char ** are optional.
1657 ***********************************************************************/
1658 int
1659 ng_path_parse(char *addr, char **nodep, char **pathp, char **hookp)
1660 {
1661 char *node, *path, *hook;
1662 int k;
1663
1664 /*
1665 * Extract absolute NODE, if any
1666 */
1667 for (path = addr; *path && *path != ':'; path++);
1668 if (*path) {
1669 node = addr; /* Here's the NODE */
1670 *path++ = '\0'; /* Here's the PATH */
1671
1672 /* Node name must not be empty */
1673 if (!*node)
1674 return -1;
1675
1676 /* A name of "." is OK; otherwise '.' not allowed */
1677 if (strcmp(node, ".") != 0) {
1678 for (k = 0; node[k]; k++)
1679 if (node[k] == '.')
1680 return -1;
1681 }
1682 } else {
1683 node = NULL; /* No absolute NODE */
1684 path = addr; /* Here's the PATH */
1685 }
1686
1687 /* Snoop for illegal characters in PATH */
1688 for (k = 0; path[k]; k++)
1689 if (path[k] == ':')
1690 return -1;
1691
1692 /* Check for no repeated dots in PATH */
1693 for (k = 0; path[k]; k++)
1694 if (path[k] == '.' && path[k + 1] == '.')
1695 return -1;
1696
1697 /* Remove extra (degenerate) dots from beginning or end of PATH */
1698 if (path[0] == '.')
1699 path++;
1700 if (*path && path[strlen(path) - 1] == '.')
1701 path[strlen(path) - 1] = 0;
1702
1703 /* If PATH has a dot, then we're not talking about a hook */
1704 if (*path) {
1705 for (hook = path, k = 0; path[k]; k++)
1706 if (path[k] == '.') {
1707 hook = NULL;
1708 break;
1709 }
1710 } else
1711 path = hook = NULL;
1712
1713 /* Done */
1714 if (nodep)
1715 *nodep = node;
1716 if (pathp)
1717 *pathp = path;
1718 if (hookp)
1719 *hookp = hook;
1720 return (0);
1721 }
1722
1723 /*
1724 * Given a path, which may be absolute or relative, and a starting node,
1725 * return the destination node.
1726 */
1727 int
1728 ng_path2noderef(node_p here, const char *address, node_p *destp,
1729 hook_p *lasthook)
1730 {
1731 char fullpath[NG_PATHSIZ];
1732 char *nodename, *path;
1733 node_p node, oldnode;
1734
1735 /* Initialize */
1736 if (destp == NULL) {
1737 TRAP_ERROR();
1738 return EINVAL;
1739 }
1740 *destp = NULL;
1741
1742 /* Make a writable copy of address for ng_path_parse() */
1743 strncpy(fullpath, address, sizeof(fullpath) - 1);
1744 fullpath[sizeof(fullpath) - 1] = '\0';
1745
1746 /* Parse out node and sequence of hooks */
1747 if (ng_path_parse(fullpath, &nodename, &path, NULL) < 0) {
1748 TRAP_ERROR();
1749 return EINVAL;
1750 }
1751
1752 /*
1753 * For an absolute address, jump to the starting node.
1754 * Note that this holds a reference on the node for us.
1755 * Don't forget to drop the reference if we don't need it.
1756 */
1757 if (nodename) {
1758 node = ng_name2noderef(here, nodename);
1759 if (node == NULL) {
1760 TRAP_ERROR();
1761 return (ENOENT);
1762 }
1763 } else {
1764 if (here == NULL) {
1765 TRAP_ERROR();
1766 return (EINVAL);
1767 }
1768 node = here;
1769 NG_NODE_REF(node);
1770 }
1771
1772 if (path == NULL) {
1773 if (lasthook != NULL)
1774 *lasthook = NULL;
1775 *destp = node;
1776 return (0);
1777 }
1778
1779 /*
1780 * Now follow the sequence of hooks
1781 *
1782 * XXXGL: The path may demolish as we go the sequence, but if
1783 * we hold the topology mutex at critical places, then, I hope,
1784 * we would always have valid pointers in hand, although the
1785 * path behind us may no longer exist.
1786 */
1787 for (;;) {
1788 hook_p hook;
1789 char *segment;
1790
1791 /*
1792 * Break out the next path segment. Replace the dot we just
1793 * found with a NUL; "path" points to the next segment (or the
1794 * NUL at the end).
1795 */
1796 for (segment = path; *path != '\0'; path++) {
1797 if (*path == '.') {
1798 *path++ = '\0';
1799 break;
1800 }
1801 }
1802
1803 /* We have a segment, so look for a hook by that name */
1804 hook = ng_findhook(node, segment);
1805
1806 TOPOLOGY_WLOCK();
1807 /* Can't get there from here... */
1808 if (hook == NULL || NG_HOOK_PEER(hook) == NULL ||
1809 NG_HOOK_NOT_VALID(hook) ||
1810 NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook))) {
1811 TRAP_ERROR();
1812 NG_NODE_UNREF(node);
1813 TOPOLOGY_WUNLOCK();
1814 return (ENOENT);
1815 }
1816
1817 /*
1818 * Hop on over to the next node
1819 * XXX
1820 * Big race conditions here as hooks and nodes go away
1821 * *** Idea.. store an ng_ID_t in each hook and use that
1822 * instead of the direct hook in this crawl?
1823 */
1824 oldnode = node;
1825 if ((node = NG_PEER_NODE(hook)))
1826 NG_NODE_REF(node); /* XXX RACE */
1827 NG_NODE_UNREF(oldnode); /* XXX another race */
1828 if (NG_NODE_NOT_VALID(node)) {
1829 NG_NODE_UNREF(node); /* XXX more races */
1830 TOPOLOGY_WUNLOCK();
1831 TRAP_ERROR();
1832 return (ENXIO);
1833 }
1834
1835 if (*path == '\0') {
1836 if (lasthook != NULL) {
1837 if (hook != NULL) {
1838 *lasthook = NG_HOOK_PEER(hook);
1839 NG_HOOK_REF(*lasthook);
1840 } else
1841 *lasthook = NULL;
1842 }
1843 TOPOLOGY_WUNLOCK();
1844 *destp = node;
1845 return (0);
1846 }
1847 TOPOLOGY_WUNLOCK();
1848 }
1849 }
1850
1851 /***************************************************************\
1852 * Input queue handling.
1853 * All activities are submitted to the node via the input queue
1854 * which implements a multiple-reader/single-writer gate.
1855 * Items which cannot be handled immediately are queued.
1856 *
1857 * read-write queue locking inline functions *
1858 \***************************************************************/
1859
1860 static __inline void ng_queue_rw(node_p node, item_p item, int rw);
1861 static __inline item_p ng_dequeue(node_p node, int *rw);
1862 static __inline item_p ng_acquire_read(node_p node, item_p item);
1863 static __inline item_p ng_acquire_write(node_p node, item_p item);
1864 static __inline void ng_leave_read(node_p node);
1865 static __inline void ng_leave_write(node_p node);
1866
1867 /*
1868 * Definition of the bits fields in the ng_queue flag word.
1869 * Defined here rather than in netgraph.h because no-one should fiddle
1870 * with them.
1871 *
1872 * The ordering here may be important! don't shuffle these.
1873 */
1874 /*-
1875 Safety Barrier--------+ (adjustable to suit taste) (not used yet)
1876 |
1877 V
1878 +-------+-------+-------+-------+-------+-------+-------+-------+
1879 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
1880 | |A|c|t|i|v|e| |R|e|a|d|e|r| |C|o|u|n|t| | | | | | | | | |P|A|
1881 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |O|W|
1882 +-------+-------+-------+-------+-------+-------+-------+-------+
1883 \___________________________ ____________________________/ | |
1884 V | |
1885 [active reader count] | |
1886 | |
1887 Operation Pending -------------------------------+ |
1888 |
1889 Active Writer ---------------------------------------+
1890
1891 Node queue has such semantics:
1892 - All flags modifications are atomic.
1893 - Reader count can be incremented only if there is no writer or pending flags.
1894 As soon as this can't be done with single operation, it is implemented with
1895 spin loop and atomic_cmpset().
1896 - Writer flag can be set only if there is no any bits set.
1897 It is implemented with atomic_cmpset().
1898 - Pending flag can be set any time, but to avoid collision on queue processing
1899 all queue fields are protected by the mutex.
1900 - Queue processing thread reads queue holding the mutex, but releases it while
1901 processing. When queue is empty pending flag is removed.
1902 */
1903
1904 #define WRITER_ACTIVE 0x00000001
1905 #define OP_PENDING 0x00000002
1906 #define READER_INCREMENT 0x00000004
1907 #define READER_MASK 0xfffffffc /* Not valid if WRITER_ACTIVE is set */
1908 #define SAFETY_BARRIER 0x00100000 /* 128K items queued should be enough */
1909
1910 /* Defines of more elaborate states on the queue */
1911 /* Mask of bits a new read cares about */
1912 #define NGQ_RMASK (WRITER_ACTIVE|OP_PENDING)
1913
1914 /* Mask of bits a new write cares about */
1915 #define NGQ_WMASK (NGQ_RMASK|READER_MASK)
1916
1917 /* Test to decide if there is something on the queue. */
1918 #define QUEUE_ACTIVE(QP) ((QP)->q_flags & OP_PENDING)
1919
1920 /* How to decide what the next queued item is. */
1921 #define HEAD_IS_READER(QP) NGI_QUEUED_READER(STAILQ_FIRST(&(QP)->queue))
1922 #define HEAD_IS_WRITER(QP) NGI_QUEUED_WRITER(STAILQ_FIRST(&(QP)->queue)) /* notused */
1923
1924 /* Read the status to decide if the next item on the queue can now run. */
1925 #define QUEUED_READER_CAN_PROCEED(QP) \
1926 (((QP)->q_flags & (NGQ_RMASK & ~OP_PENDING)) == 0)
1927 #define QUEUED_WRITER_CAN_PROCEED(QP) \
1928 (((QP)->q_flags & (NGQ_WMASK & ~OP_PENDING)) == 0)
1929
1930 /* Is there a chance of getting ANY work off the queue? */
1931 #define NEXT_QUEUED_ITEM_CAN_PROCEED(QP) \
1932 ((HEAD_IS_READER(QP)) ? QUEUED_READER_CAN_PROCEED(QP) : \
1933 QUEUED_WRITER_CAN_PROCEED(QP))
1934
1935 #define NGQRW_R 0
1936 #define NGQRW_W 1
1937
1938 #define NGQ2_WORKQ 0x00000001
1939
1940 /*
1941 * Taking into account the current state of the queue and node, possibly take
1942 * the next entry off the queue and return it. Return NULL if there was
1943 * nothing we could return, either because there really was nothing there, or
1944 * because the node was in a state where it cannot yet process the next item
1945 * on the queue.
1946 */
1947 static __inline item_p
1948 ng_dequeue(node_p node, int *rw)
1949 {
1950 item_p item;
1951 struct ng_queue *ngq = &node->nd_input_queue;
1952
1953 /* This MUST be called with the mutex held. */
1954 mtx_assert(&ngq->q_mtx, MA_OWNED);
1955
1956 /* If there is nothing queued, then just return. */
1957 if (!QUEUE_ACTIVE(ngq)) {
1958 CTR4(KTR_NET, "%20s: node [%x] (%p) queue empty; "
1959 "queue flags 0x%lx", __func__,
1960 node->nd_ID, node, ngq->q_flags);
1961 return (NULL);
1962 }
1963
1964 /*
1965 * From here, we can assume there is a head item.
1966 * We need to find out what it is and if it can be dequeued, given
1967 * the current state of the node.
1968 */
1969 if (HEAD_IS_READER(ngq)) {
1970 while (1) {
1971 long t = ngq->q_flags;
1972 if (t & WRITER_ACTIVE) {
1973 /* There is writer, reader can't proceed. */
1974 CTR4(KTR_NET, "%20s: node [%x] (%p) queued "
1975 "reader can't proceed; queue flags 0x%lx",
1976 __func__, node->nd_ID, node, t);
1977 return (NULL);
1978 }
1979 if (atomic_cmpset_acq_int(&ngq->q_flags, t,
1980 t + READER_INCREMENT))
1981 break;
1982 cpu_spinwait();
1983 }
1984 /* We have got reader lock for the node. */
1985 *rw = NGQRW_R;
1986 } else if (atomic_cmpset_acq_int(&ngq->q_flags, OP_PENDING,
1987 OP_PENDING + WRITER_ACTIVE)) {
1988 /* We have got writer lock for the node. */
1989 *rw = NGQRW_W;
1990 } else {
1991 /* There is somebody other, writer can't proceed. */
1992 CTR4(KTR_NET, "%20s: node [%x] (%p) queued writer can't "
1993 "proceed; queue flags 0x%lx", __func__, node->nd_ID, node,
1994 ngq->q_flags);
1995 return (NULL);
1996 }
1997
1998 /*
1999 * Now we dequeue the request (whatever it may be) and correct the
2000 * pending flags and the next and last pointers.
2001 */
2002 item = STAILQ_FIRST(&ngq->queue);
2003 STAILQ_REMOVE_HEAD(&ngq->queue, el_next);
2004 if (STAILQ_EMPTY(&ngq->queue))
2005 atomic_clear_int(&ngq->q_flags, OP_PENDING);
2006 CTR6(KTR_NET, "%20s: node [%x] (%p) returning item %p as %s; queue "
2007 "flags 0x%lx", __func__, node->nd_ID, node, item, *rw ? "WRITER" :
2008 "READER", ngq->q_flags);
2009 return (item);
2010 }
2011
2012 /*
2013 * Queue a packet to be picked up later by someone else.
2014 * If the queue could be run now, add node to the queue handler's worklist.
2015 */
2016 static __inline void
2017 ng_queue_rw(node_p node, item_p item, int rw)
2018 {
2019 struct ng_queue *ngq = &node->nd_input_queue;
2020 if (rw == NGQRW_W)
2021 NGI_SET_WRITER(item);
2022 else
2023 NGI_SET_READER(item);
2024 item->depth = 1;
2025
2026 NG_QUEUE_LOCK(ngq);
2027 /* Set OP_PENDING flag and enqueue the item. */
2028 atomic_set_int(&ngq->q_flags, OP_PENDING);
2029 STAILQ_INSERT_TAIL(&ngq->queue, item, el_next);
2030
2031 CTR5(KTR_NET, "%20s: node [%x] (%p) queued item %p as %s", __func__,
2032 node->nd_ID, node, item, rw ? "WRITER" : "READER" );
2033
2034 /*
2035 * We can take the worklist lock with the node locked
2036 * BUT NOT THE REVERSE!
2037 */
2038 if (NEXT_QUEUED_ITEM_CAN_PROCEED(ngq))
2039 ng_worklist_add(node);
2040 NG_QUEUE_UNLOCK(ngq);
2041 }
2042
2043 /* Acquire reader lock on node. If node is busy, queue the packet. */
2044 static __inline item_p
2045 ng_acquire_read(node_p node, item_p item)
2046 {
2047 KASSERT(node != &ng_deadnode,
2048 ("%s: working on deadnode", __func__));
2049
2050 /* Reader needs node without writer and pending items. */
2051 for (;;) {
2052 long t = node->nd_input_queue.q_flags;
2053 if (t & NGQ_RMASK)
2054 break; /* Node is not ready for reader. */
2055 if (atomic_cmpset_acq_int(&node->nd_input_queue.q_flags, t,
2056 t + READER_INCREMENT)) {
2057 /* Successfully grabbed node */
2058 CTR4(KTR_NET, "%20s: node [%x] (%p) acquired item %p",
2059 __func__, node->nd_ID, node, item);
2060 return (item);
2061 }
2062 cpu_spinwait();
2063 }
2064
2065 /* Queue the request for later. */
2066 ng_queue_rw(node, item, NGQRW_R);
2067
2068 return (NULL);
2069 }
2070
2071 /* Acquire writer lock on node. If node is busy, queue the packet. */
2072 static __inline item_p
2073 ng_acquire_write(node_p node, item_p item)
2074 {
2075 KASSERT(node != &ng_deadnode,
2076 ("%s: working on deadnode", __func__));
2077
2078 /* Writer needs completely idle node. */
2079 if (atomic_cmpset_acq_int(&node->nd_input_queue.q_flags, 0,
2080 WRITER_ACTIVE)) {
2081 /* Successfully grabbed node */
2082 CTR4(KTR_NET, "%20s: node [%x] (%p) acquired item %p",
2083 __func__, node->nd_ID, node, item);
2084 return (item);
2085 }
2086
2087 /* Queue the request for later. */
2088 ng_queue_rw(node, item, NGQRW_W);
2089
2090 return (NULL);
2091 }
2092
2093 #if 0
2094 static __inline item_p
2095 ng_upgrade_write(node_p node, item_p item)
2096 {
2097 struct ng_queue *ngq = &node->nd_input_queue;
2098 KASSERT(node != &ng_deadnode,
2099 ("%s: working on deadnode", __func__));
2100
2101 NGI_SET_WRITER(item);
2102
2103 NG_QUEUE_LOCK(ngq);
2104
2105 /*
2106 * There will never be no readers as we are there ourselves.
2107 * Set the WRITER_ACTIVE flags ASAP to block out fast track readers.
2108 * The caller we are running from will call ng_leave_read()
2109 * soon, so we must account for that. We must leave again with the
2110 * READER lock. If we find other readers, then
2111 * queue the request for later. However "later" may be rignt now
2112 * if there are no readers. We don't really care if there are queued
2113 * items as we will bypass them anyhow.
2114 */
2115 atomic_add_int(&ngq->q_flags, WRITER_ACTIVE - READER_INCREMENT);
2116 if ((ngq->q_flags & (NGQ_WMASK & ~OP_PENDING)) == WRITER_ACTIVE) {
2117 NG_QUEUE_UNLOCK(ngq);
2118
2119 /* It's just us, act on the item. */
2120 /* will NOT drop writer lock when done */
2121 ng_apply_item(node, item, 0);
2122
2123 /*
2124 * Having acted on the item, atomically
2125 * downgrade back to READER and finish up.
2126 */
2127 atomic_add_int(&ngq->q_flags, READER_INCREMENT - WRITER_ACTIVE);
2128
2129 /* Our caller will call ng_leave_read() */
2130 return;
2131 }
2132 /*
2133 * It's not just us active, so queue us AT THE HEAD.
2134 * "Why?" I hear you ask.
2135 * Put us at the head of the queue as we've already been
2136 * through it once. If there is nothing else waiting,
2137 * set the correct flags.
2138 */
2139 if (STAILQ_EMPTY(&ngq->queue)) {
2140 /* We've gone from, 0 to 1 item in the queue */
2141 atomic_set_int(&ngq->q_flags, OP_PENDING);
2142
2143 CTR3(KTR_NET, "%20s: node [%x] (%p) set OP_PENDING", __func__,
2144 node->nd_ID, node);
2145 };
2146 STAILQ_INSERT_HEAD(&ngq->queue, item, el_next);
2147 CTR4(KTR_NET, "%20s: node [%x] (%p) requeued item %p as WRITER",
2148 __func__, node->nd_ID, node, item );
2149
2150 /* Reverse what we did above. That downgrades us back to reader */
2151 atomic_add_int(&ngq->q_flags, READER_INCREMENT - WRITER_ACTIVE);
2152 if (QUEUE_ACTIVE(ngq) && NEXT_QUEUED_ITEM_CAN_PROCEED(ngq))
2153 ng_worklist_add(node);
2154 NG_QUEUE_UNLOCK(ngq);
2155
2156 return;
2157 }
2158 #endif
2159
2160 /* Release reader lock. */
2161 static __inline void
2162 ng_leave_read(node_p node)
2163 {
2164 atomic_subtract_rel_int(&node->nd_input_queue.q_flags, READER_INCREMENT);
2165 }
2166
2167 /* Release writer lock. */
2168 static __inline void
2169 ng_leave_write(node_p node)
2170 {
2171 atomic_clear_rel_int(&node->nd_input_queue.q_flags, WRITER_ACTIVE);
2172 }
2173
2174 /* Purge node queue. Called on node shutdown. */
2175 static void
2176 ng_flush_input_queue(node_p node)
2177 {
2178 struct ng_queue *ngq = &node->nd_input_queue;
2179 item_p item;
2180
2181 NG_QUEUE_LOCK(ngq);
2182 while ((item = STAILQ_FIRST(&ngq->queue)) != NULL) {
2183 STAILQ_REMOVE_HEAD(&ngq->queue, el_next);
2184 if (STAILQ_EMPTY(&ngq->queue))
2185 atomic_clear_int(&ngq->q_flags, OP_PENDING);
2186 NG_QUEUE_UNLOCK(ngq);
2187
2188 /* If the item is supplying a callback, call it with an error */
2189 if (item->apply != NULL) {
2190 if (item->depth == 1)
2191 item->apply->error = ENOENT;
2192 if (refcount_release(&item->apply->refs)) {
2193 (*item->apply->apply)(item->apply->context,
2194 item->apply->error);
2195 }
2196 }
2197 NG_FREE_ITEM(item);
2198 NG_QUEUE_LOCK(ngq);
2199 }
2200 NG_QUEUE_UNLOCK(ngq);
2201 }
2202
2203 /***********************************************************************
2204 * Externally visible method for sending or queueing messages or data.
2205 ***********************************************************************/
2206
2207 /*
2208 * The module code should have filled out the item correctly by this stage:
2209 * Common:
2210 * reference to destination node.
2211 * Reference to destination rcv hook if relevant.
2212 * apply pointer must be or NULL or reference valid struct ng_apply_info.
2213 * Data:
2214 * pointer to mbuf
2215 * Control_Message:
2216 * pointer to msg.
2217 * ID of original sender node. (return address)
2218 * Function:
2219 * Function pointer
2220 * void * argument
2221 * integer argument
2222 *
2223 * The nodes have several routines and macros to help with this task:
2224 */
2225
2226 int
2227 ng_snd_item(item_p item, int flags)
2228 {
2229 hook_p hook;
2230 node_p node;
2231 int queue, rw;
2232 struct ng_queue *ngq;
2233 int error = 0;
2234
2235 /* We are sending item, so it must be present! */
2236 KASSERT(item != NULL, ("ng_snd_item: item is NULL"));
2237
2238 #ifdef NETGRAPH_DEBUG
2239 _ngi_check(item, __FILE__, __LINE__);
2240 #endif
2241
2242 /* Item was sent once more, postpone apply() call. */
2243 if (item->apply)
2244 refcount_acquire(&item->apply->refs);
2245
2246 node = NGI_NODE(item);
2247 /* Node is never optional. */
2248 KASSERT(node != NULL, ("ng_snd_item: node is NULL"));
2249
2250 hook = NGI_HOOK(item);
2251 /* Valid hook and mbuf are mandatory for data. */
2252 if ((item->el_flags & NGQF_TYPE) == NGQF_DATA) {
2253 KASSERT(hook != NULL, ("ng_snd_item: hook for data is NULL"));
2254 if (NGI_M(item) == NULL)
2255 ERROUT(EINVAL);
2256 CHECK_DATA_MBUF(NGI_M(item));
2257 }
2258
2259 /*
2260 * If the item or the node specifies single threading, force
2261 * writer semantics. Similarly, the node may say one hook always
2262 * produces writers. These are overrides.
2263 */
2264 if (((item->el_flags & NGQF_RW) == NGQF_WRITER) ||
2265 (node->nd_flags & NGF_FORCE_WRITER) ||
2266 (hook && (hook->hk_flags & HK_FORCE_WRITER))) {
2267 rw = NGQRW_W;
2268 } else {
2269 rw = NGQRW_R;
2270 }
2271
2272 /*
2273 * If sender or receiver requests queued delivery, or call graph
2274 * loops back from outbound to inbound path, or stack usage
2275 * level is dangerous - enqueue message.
2276 */
2277 if ((flags & NG_QUEUE) || (hook && (hook->hk_flags & HK_QUEUE))) {
2278 queue = 1;
2279 } else if (hook && (hook->hk_flags & HK_TO_INBOUND) &&
2280 curthread->td_ng_outbound) {
2281 queue = 1;
2282 } else {
2283 queue = 0;
2284 #ifdef GET_STACK_USAGE
2285 /*
2286 * Most of netgraph nodes have small stack consumption and
2287 * for them 25% of free stack space is more than enough.
2288 * Nodes/hooks with higher stack usage should be marked as
2289 * HI_STACK. For them 50% of stack will be guaranteed then.
2290 * XXX: Values 25% and 50% are completely empirical.
2291 */
2292 size_t st, su, sl;
2293 GET_STACK_USAGE(st, su);
2294 sl = st - su;
2295 if ((sl * 4 < st) || ((sl * 2 < st) &&
2296 ((node->nd_flags & NGF_HI_STACK) || (hook &&
2297 (hook->hk_flags & HK_HI_STACK)))))
2298 queue = 1;
2299 #endif
2300 }
2301
2302 if (queue) {
2303 /* Put it on the queue for that node*/
2304 ng_queue_rw(node, item, rw);
2305 return ((flags & NG_PROGRESS) ? EINPROGRESS : 0);
2306 }
2307
2308 /*
2309 * We already decided how we will be queueud or treated.
2310 * Try get the appropriate operating permission.
2311 */
2312 if (rw == NGQRW_R)
2313 item = ng_acquire_read(node, item);
2314 else
2315 item = ng_acquire_write(node, item);
2316
2317 /* Item was queued while trying to get permission. */
2318 if (item == NULL)
2319 return ((flags & NG_PROGRESS) ? EINPROGRESS : 0);
2320
2321 NGI_GET_NODE(item, node); /* zaps stored node */
2322
2323 item->depth++;
2324 error = ng_apply_item(node, item, rw); /* drops r/w lock when done */
2325
2326 /* If something is waiting on queue and ready, schedule it. */
2327 ngq = &node->nd_input_queue;
2328 if (QUEUE_ACTIVE(ngq)) {
2329 NG_QUEUE_LOCK(ngq);
2330 if (QUEUE_ACTIVE(ngq) && NEXT_QUEUED_ITEM_CAN_PROCEED(ngq))
2331 ng_worklist_add(node);
2332 NG_QUEUE_UNLOCK(ngq);
2333 }
2334
2335 /*
2336 * Node may go away as soon as we remove the reference.
2337 * Whatever we do, DO NOT access the node again!
2338 */
2339 NG_NODE_UNREF(node);
2340
2341 return (error);
2342
2343 done:
2344 /* If was not sent, apply callback here. */
2345 if (item->apply != NULL) {
2346 if (item->depth == 0 && error != 0)
2347 item->apply->error = error;
2348 if (refcount_release(&item->apply->refs)) {
2349 (*item->apply->apply)(item->apply->context,
2350 item->apply->error);
2351 }
2352 }
2353
2354 NG_FREE_ITEM(item);
2355 return (error);
2356 }
2357
2358 /*
2359 * We have an item that was possibly queued somewhere.
2360 * It should contain all the information needed
2361 * to run it on the appropriate node/hook.
2362 * If there is apply pointer and we own the last reference, call apply().
2363 */
2364 static int
2365 ng_apply_item(node_p node, item_p item, int rw)
2366 {
2367 hook_p hook;
2368 ng_rcvdata_t *rcvdata;
2369 ng_rcvmsg_t *rcvmsg;
2370 struct ng_apply_info *apply;
2371 int error = 0, depth;
2372
2373 /* Node and item are never optional. */
2374 KASSERT(node != NULL, ("ng_apply_item: node is NULL"));
2375 KASSERT(item != NULL, ("ng_apply_item: item is NULL"));
2376
2377 NGI_GET_HOOK(item, hook); /* clears stored hook */
2378 #ifdef NETGRAPH_DEBUG
2379 _ngi_check(item, __FILE__, __LINE__);
2380 #endif
2381
2382 apply = item->apply;
2383 depth = item->depth;
2384
2385 switch (item->el_flags & NGQF_TYPE) {
2386 case NGQF_DATA:
2387 /*
2388 * Check things are still ok as when we were queued.
2389 */
2390 KASSERT(hook != NULL, ("ng_apply_item: hook for data is NULL"));
2391 if (NG_HOOK_NOT_VALID(hook) ||
2392 NG_NODE_NOT_VALID(node)) {
2393 error = EIO;
2394 NG_FREE_ITEM(item);
2395 break;
2396 }
2397 /*
2398 * If no receive method, just silently drop it.
2399 * Give preference to the hook over-ride method.
2400 */
2401 if ((!(rcvdata = hook->hk_rcvdata)) &&
2402 (!(rcvdata = NG_HOOK_NODE(hook)->nd_type->rcvdata))) {
2403 error = 0;
2404 NG_FREE_ITEM(item);
2405 break;
2406 }
2407 error = (*rcvdata)(hook, item);
2408 break;
2409 case NGQF_MESG:
2410 if (hook && NG_HOOK_NOT_VALID(hook)) {
2411 /*
2412 * The hook has been zapped then we can't use it.
2413 * Immediately drop its reference.
2414 * The message may not need it.
2415 */
2416 NG_HOOK_UNREF(hook);
2417 hook = NULL;
2418 }
2419 /*
2420 * Similarly, if the node is a zombie there is
2421 * nothing we can do with it, drop everything.
2422 */
2423 if (NG_NODE_NOT_VALID(node)) {
2424 TRAP_ERROR();
2425 error = EINVAL;
2426 NG_FREE_ITEM(item);
2427 break;
2428 }
2429 /*
2430 * Call the appropriate message handler for the object.
2431 * It is up to the message handler to free the message.
2432 * If it's a generic message, handle it generically,
2433 * otherwise call the type's message handler (if it exists).
2434 * XXX (race). Remember that a queued message may
2435 * reference a node or hook that has just been
2436 * invalidated. It will exist as the queue code
2437 * is holding a reference, but..
2438 */
2439 if ((NGI_MSG(item)->header.typecookie == NGM_GENERIC_COOKIE) &&
2440 ((NGI_MSG(item)->header.flags & NGF_RESP) == 0)) {
2441 error = ng_generic_msg(node, item, hook);
2442 break;
2443 }
2444 if (((!hook) || (!(rcvmsg = hook->hk_rcvmsg))) &&
2445 (!(rcvmsg = node->nd_type->rcvmsg))) {
2446 TRAP_ERROR();
2447 error = 0;
2448 NG_FREE_ITEM(item);
2449 break;
2450 }
2451 error = (*rcvmsg)(node, item, hook);
2452 break;
2453 case NGQF_FN:
2454 case NGQF_FN2:
2455 /*
2456 * In the case of the shutdown message we allow it to hit
2457 * even if the node is invalid.
2458 */
2459 if (NG_NODE_NOT_VALID(node) &&
2460 NGI_FN(item) != &ng_rmnode) {
2461 TRAP_ERROR();
2462 error = EINVAL;
2463 NG_FREE_ITEM(item);
2464 break;
2465 }
2466 /* Same is about some internal functions and invalid hook. */
2467 if (hook && NG_HOOK_NOT_VALID(hook) &&
2468 NGI_FN2(item) != &ng_con_part2 &&
2469 NGI_FN2(item) != &ng_con_part3 &&
2470 NGI_FN(item) != &ng_rmhook_part2) {
2471 TRAP_ERROR();
2472 error = EINVAL;
2473 NG_FREE_ITEM(item);
2474 break;
2475 }
2476
2477 if ((item->el_flags & NGQF_TYPE) == NGQF_FN) {
2478 (*NGI_FN(item))(node, hook, NGI_ARG1(item),
2479 NGI_ARG2(item));
2480 NG_FREE_ITEM(item);
2481 } else /* it is NGQF_FN2 */
2482 error = (*NGI_FN2(item))(node, item, hook);
2483 break;
2484 }
2485 /*
2486 * We held references on some of the resources
2487 * that we took from the item. Now that we have
2488 * finished doing everything, drop those references.
2489 */
2490 if (hook)
2491 NG_HOOK_UNREF(hook);
2492
2493 if (rw == NGQRW_R)
2494 ng_leave_read(node);
2495 else
2496 ng_leave_write(node);
2497
2498 /* Apply callback. */
2499 if (apply != NULL) {
2500 if (depth == 1 && error != 0)
2501 apply->error = error;
2502 if (refcount_release(&apply->refs))
2503 (*apply->apply)(apply->context, apply->error);
2504 }
2505
2506 return (error);
2507 }
2508
2509 /***********************************************************************
2510 * Implement the 'generic' control messages
2511 ***********************************************************************/
2512 static int
2513 ng_generic_msg(node_p here, item_p item, hook_p lasthook)
2514 {
2515 int error = 0;
2516 struct ng_mesg *msg;
2517 struct ng_mesg *resp = NULL;
2518
2519 NGI_GET_MSG(item, msg);
2520 if (msg->header.typecookie != NGM_GENERIC_COOKIE) {
2521 TRAP_ERROR();
2522 error = EINVAL;
2523 goto out;
2524 }
2525 switch (msg->header.cmd) {
2526 case NGM_SHUTDOWN:
2527 ng_rmnode(here, NULL, NULL, 0);
2528 break;
2529 case NGM_MKPEER:
2530 {
2531 struct ngm_mkpeer *const mkp = (struct ngm_mkpeer *) msg->data;
2532
2533 if (msg->header.arglen != sizeof(*mkp)) {
2534 TRAP_ERROR();
2535 error = EINVAL;
2536 break;
2537 }
2538 mkp->type[sizeof(mkp->type) - 1] = '\0';
2539 mkp->ourhook[sizeof(mkp->ourhook) - 1] = '\0';
2540 mkp->peerhook[sizeof(mkp->peerhook) - 1] = '\0';
2541 error = ng_mkpeer(here, mkp->ourhook, mkp->peerhook, mkp->type);
2542 break;
2543 }
2544 case NGM_CONNECT:
2545 {
2546 struct ngm_connect *const con =
2547 (struct ngm_connect *) msg->data;
2548 node_p node2;
2549
2550 if (msg->header.arglen != sizeof(*con)) {
2551 TRAP_ERROR();
2552 error = EINVAL;
2553 break;
2554 }
2555 con->path[sizeof(con->path) - 1] = '\0';
2556 con->ourhook[sizeof(con->ourhook) - 1] = '\0';
2557 con->peerhook[sizeof(con->peerhook) - 1] = '\0';
2558 /* Don't forget we get a reference.. */
2559 error = ng_path2noderef(here, con->path, &node2, NULL);
2560 if (error)
2561 break;
2562 error = ng_con_nodes(item, here, con->ourhook,
2563 node2, con->peerhook);
2564 NG_NODE_UNREF(node2);
2565 break;
2566 }
2567 case NGM_NAME:
2568 {
2569 struct ngm_name *const nam = (struct ngm_name *) msg->data;
2570
2571 if (msg->header.arglen != sizeof(*nam)) {
2572 TRAP_ERROR();
2573 error = EINVAL;
2574 break;
2575 }
2576 nam->name[sizeof(nam->name) - 1] = '\0';
2577 error = ng_name_node(here, nam->name);
2578 break;
2579 }
2580 case NGM_RMHOOK:
2581 {
2582 struct ngm_rmhook *const rmh = (struct ngm_rmhook *) msg->data;
2583 hook_p hook;
2584
2585 if (msg->header.arglen != sizeof(*rmh)) {
2586 TRAP_ERROR();
2587 error = EINVAL;
2588 break;
2589 }
2590 rmh->ourhook[sizeof(rmh->ourhook) - 1] = '\0';
2591 if ((hook = ng_findhook(here, rmh->ourhook)) != NULL)
2592 ng_destroy_hook(hook);
2593 break;
2594 }
2595 case NGM_NODEINFO:
2596 {
2597 struct nodeinfo *ni;
2598
2599 NG_MKRESPONSE(resp, msg, sizeof(*ni), M_NOWAIT);
2600 if (resp == NULL) {
2601 error = ENOMEM;
2602 break;
2603 }
2604
2605 /* Fill in node info */
2606 ni = (struct nodeinfo *) resp->data;
2607 if (NG_NODE_HAS_NAME(here))
2608 strcpy(ni->name, NG_NODE_NAME(here));
2609 strcpy(ni->type, here->nd_type->name);
2610 ni->id = ng_node2ID(here);
2611 ni->hooks = here->nd_numhooks;
2612 break;
2613 }
2614 case NGM_LISTHOOKS:
2615 {
2616 const int nhooks = here->nd_numhooks;
2617 struct hooklist *hl;
2618 struct nodeinfo *ni;
2619 hook_p hook;
2620
2621 /* Get response struct */
2622 NG_MKRESPONSE(resp, msg, sizeof(*hl) +
2623 (nhooks * sizeof(struct linkinfo)), M_NOWAIT);
2624 if (resp == NULL) {
2625 error = ENOMEM;
2626 break;
2627 }
2628 hl = (struct hooklist *) resp->data;
2629 ni = &hl->nodeinfo;
2630
2631 /* Fill in node info */
2632 if (NG_NODE_HAS_NAME(here))
2633 strcpy(ni->name, NG_NODE_NAME(here));
2634 strcpy(ni->type, here->nd_type->name);
2635 ni->id = ng_node2ID(here);
2636
2637 /* Cycle through the linked list of hooks */
2638 ni->hooks = 0;
2639 LIST_FOREACH(hook, &here->nd_hooks, hk_hooks) {
2640 struct linkinfo *const link = &hl->link[ni->hooks];
2641
2642 if (ni->hooks >= nhooks) {
2643 log(LOG_ERR, "%s: number of %s changed\n",
2644 __func__, "hooks");
2645 break;
2646 }
2647 if (NG_HOOK_NOT_VALID(hook))
2648 continue;
2649 strcpy(link->ourhook, NG_HOOK_NAME(hook));
2650 strcpy(link->peerhook, NG_PEER_HOOK_NAME(hook));
2651 if (NG_PEER_NODE_NAME(hook)[0] != '\0')
2652 strcpy(link->nodeinfo.name,
2653 NG_PEER_NODE_NAME(hook));
2654 strcpy(link->nodeinfo.type,
2655 NG_PEER_NODE(hook)->nd_type->name);
2656 link->nodeinfo.id = ng_node2ID(NG_PEER_NODE(hook));
2657 link->nodeinfo.hooks = NG_PEER_NODE(hook)->nd_numhooks;
2658 ni->hooks++;
2659 }
2660 break;
2661 }
2662
2663 case NGM_LISTNODES:
2664 {
2665 struct namelist *nl;
2666 node_p node;
2667 int i;
2668
2669 IDHASH_RLOCK();
2670 /* Get response struct. */
2671 NG_MKRESPONSE(resp, msg, sizeof(*nl) +
2672 (V_ng_nodes * sizeof(struct nodeinfo)), M_NOWAIT);
2673 if (resp == NULL) {
2674 IDHASH_RUNLOCK();
2675 error = ENOMEM;
2676 break;
2677 }
2678 nl = (struct namelist *) resp->data;
2679
2680 /* Cycle through the lists of nodes. */
2681 nl->numnames = 0;
2682 for (i = 0; i <= V_ng_ID_hmask; i++) {
2683 LIST_FOREACH(node, &V_ng_ID_hash[i], nd_idnodes) {
2684 struct nodeinfo *const np =
2685 &nl->nodeinfo[nl->numnames];
2686
2687 if (NG_NODE_NOT_VALID(node))
2688 continue;
2689 if (NG_NODE_HAS_NAME(node))
2690 strcpy(np->name, NG_NODE_NAME(node));
2691 strcpy(np->type, node->nd_type->name);
2692 np->id = ng_node2ID(node);
2693 np->hooks = node->nd_numhooks;
2694 KASSERT(nl->numnames < V_ng_nodes,
2695 ("%s: no space", __func__));
2696 nl->numnames++;
2697 }
2698 }
2699 IDHASH_RUNLOCK();
2700 break;
2701 }
2702 case NGM_LISTNAMES:
2703 {
2704 struct namelist *nl;
2705 node_p node;
2706 int i;
2707
2708 NAMEHASH_RLOCK();
2709 /* Get response struct. */
2710 NG_MKRESPONSE(resp, msg, sizeof(*nl) +
2711 (V_ng_named_nodes * sizeof(struct nodeinfo)), M_NOWAIT);
2712 if (resp == NULL) {
2713 NAMEHASH_RUNLOCK();
2714 error = ENOMEM;
2715 break;
2716 }
2717 nl = (struct namelist *) resp->data;
2718
2719 /* Cycle through the lists of nodes. */
2720 nl->numnames = 0;
2721 for (i = 0; i <= V_ng_name_hmask; i++) {
2722 LIST_FOREACH(node, &V_ng_name_hash[i], nd_nodes) {
2723 struct nodeinfo *const np =
2724 &nl->nodeinfo[nl->numnames];
2725
2726 if (NG_NODE_NOT_VALID(node))
2727 continue;
2728 strcpy(np->name, NG_NODE_NAME(node));
2729 strcpy(np->type, node->nd_type->name);
2730 np->id = ng_node2ID(node);
2731 np->hooks = node->nd_numhooks;
2732 KASSERT(nl->numnames < V_ng_named_nodes,
2733 ("%s: no space", __func__));
2734 nl->numnames++;
2735 }
2736 }
2737 NAMEHASH_RUNLOCK();
2738 break;
2739 }
2740
2741 case NGM_LISTTYPES:
2742 {
2743 struct typelist *tl;
2744 struct ng_type *type;
2745 int num = 0;
2746
2747 TYPELIST_RLOCK();
2748 /* Count number of types */
2749 LIST_FOREACH(type, &ng_typelist, types)
2750 num++;
2751
2752 /* Get response struct */
2753 NG_MKRESPONSE(resp, msg, sizeof(*tl) +
2754 (num * sizeof(struct typeinfo)), M_NOWAIT);
2755 if (resp == NULL) {
2756 TYPELIST_RUNLOCK();
2757 error = ENOMEM;
2758 break;
2759 }
2760 tl = (struct typelist *) resp->data;
2761
2762 /* Cycle through the linked list of types */
2763 tl->numtypes = 0;
2764 LIST_FOREACH(type, &ng_typelist, types) {
2765 struct typeinfo *const tp = &tl->typeinfo[tl->numtypes];
2766
2767 strcpy(tp->type_name, type->name);
2768 tp->numnodes = type->refs - 1; /* don't count list */
2769 KASSERT(tl->numtypes < num, ("%s: no space", __func__));
2770 tl->numtypes++;
2771 }
2772 TYPELIST_RUNLOCK();
2773 break;
2774 }
2775
2776 case NGM_BINARY2ASCII:
2777 {
2778 int bufSize = 1024;
2779 const struct ng_parse_type *argstype;
2780 const struct ng_cmdlist *c;
2781 struct ng_mesg *binary, *ascii;
2782
2783 /* Data area must contain a valid netgraph message */
2784 binary = (struct ng_mesg *)msg->data;
2785 if (msg->header.arglen < sizeof(struct ng_mesg) ||
2786 (msg->header.arglen - sizeof(struct ng_mesg) <
2787 binary->header.arglen)) {
2788 TRAP_ERROR();
2789 error = EINVAL;
2790 break;
2791 }
2792 retry_b2a:
2793 /* Get a response message with lots of room */
2794 NG_MKRESPONSE(resp, msg, sizeof(*ascii) + bufSize, M_NOWAIT);
2795 if (resp == NULL) {
2796 error = ENOMEM;
2797 break;
2798 }
2799 ascii = (struct ng_mesg *)resp->data;
2800
2801 /* Copy binary message header to response message payload */
2802 bcopy(binary, ascii, sizeof(*binary));
2803
2804 /* Find command by matching typecookie and command number */
2805 for (c = here->nd_type->cmdlist; c != NULL && c->name != NULL;
2806 c++) {
2807 if (binary->header.typecookie == c->cookie &&
2808 binary->header.cmd == c->cmd)
2809 break;
2810 }
2811 if (c == NULL || c->name == NULL) {
2812 for (c = ng_generic_cmds; c->name != NULL; c++) {
2813 if (binary->header.typecookie == c->cookie &&
2814 binary->header.cmd == c->cmd)
2815 break;
2816 }
2817 if (c->name == NULL) {
2818 NG_FREE_MSG(resp);
2819 error = ENOSYS;
2820 break;
2821 }
2822 }
2823
2824 /* Convert command name to ASCII */
2825 snprintf(ascii->header.cmdstr, sizeof(ascii->header.cmdstr),
2826 "%s", c->name);
2827
2828 /* Convert command arguments to ASCII */
2829 argstype = (binary->header.flags & NGF_RESP) ?
2830 c->respType : c->mesgType;
2831 if (argstype == NULL) {
2832 *ascii->data = '\0';
2833 } else {
2834 error = ng_unparse(argstype, (u_char *)binary->data,
2835 ascii->data, bufSize);
2836 if (error == ERANGE) {
2837 NG_FREE_MSG(resp);
2838 bufSize *= 2;
2839 goto retry_b2a;
2840 } else if (error) {
2841 NG_FREE_MSG(resp);
2842 break;
2843 }
2844 }
2845
2846 /* Return the result as struct ng_mesg plus ASCII string */
2847 bufSize = strlen(ascii->data) + 1;
2848 ascii->header.arglen = bufSize;
2849 resp->header.arglen = sizeof(*ascii) + bufSize;
2850 break;
2851 }
2852
2853 case NGM_ASCII2BINARY:
2854 {
2855 int bufSize = 20 * 1024; /* XXX hard coded constant */
2856 const struct ng_cmdlist *c;
2857 const struct ng_parse_type *argstype;
2858 struct ng_mesg *ascii, *binary;
2859 int off = 0;
2860
2861 /* Data area must contain at least a struct ng_mesg + '\0' */
2862 ascii = (struct ng_mesg *)msg->data;
2863 if ((msg->header.arglen < sizeof(*ascii) + 1) ||
2864 (ascii->header.arglen < 1) ||
2865 (msg->header.arglen < sizeof(*ascii) +
2866 ascii->header.arglen)) {
2867 TRAP_ERROR();
2868 error = EINVAL;
2869 break;
2870 }
2871 ascii->data[ascii->header.arglen - 1] = '\0';
2872
2873 /* Get a response message with lots of room */
2874 NG_MKRESPONSE(resp, msg, sizeof(*binary) + bufSize, M_NOWAIT);
2875 if (resp == NULL) {
2876 error = ENOMEM;
2877 break;
2878 }
2879 binary = (struct ng_mesg *)resp->data;
2880
2881 /* Copy ASCII message header to response message payload */
2882 bcopy(ascii, binary, sizeof(*ascii));
2883
2884 /* Find command by matching ASCII command string */
2885 for (c = here->nd_type->cmdlist;
2886 c != NULL && c->name != NULL; c++) {
2887 if (strcmp(ascii->header.cmdstr, c->name) == 0)
2888 break;
2889 }
2890 if (c == NULL || c->name == NULL) {
2891 for (c = ng_generic_cmds; c->name != NULL; c++) {
2892 if (strcmp(ascii->header.cmdstr, c->name) == 0)
2893 break;
2894 }
2895 if (c->name == NULL) {
2896 NG_FREE_MSG(resp);
2897 error = ENOSYS;
2898 break;
2899 }
2900 }
2901
2902 /* Convert command name to binary */
2903 binary->header.cmd = c->cmd;
2904 binary->header.typecookie = c->cookie;
2905
2906 /* Convert command arguments to binary */
2907 argstype = (binary->header.flags & NGF_RESP) ?
2908 c->respType : c->mesgType;
2909 if (argstype == NULL) {
2910 bufSize = 0;
2911 } else {
2912 if ((error = ng_parse(argstype, ascii->data, &off,
2913 (u_char *)binary->data, &bufSize)) != 0) {
2914 NG_FREE_MSG(resp);
2915 break;
2916 }
2917 }
2918
2919 /* Return the result */
2920 binary->header.arglen = bufSize;
2921 resp->header.arglen = sizeof(*binary) + bufSize;
2922 break;
2923 }
2924
2925 case NGM_TEXT_CONFIG:
2926 case NGM_TEXT_STATUS:
2927 /*
2928 * This one is tricky as it passes the command down to the
2929 * actual node, even though it is a generic type command.
2930 * This means we must assume that the item/msg is already freed
2931 * when control passes back to us.
2932 */
2933 if (here->nd_type->rcvmsg != NULL) {
2934 NGI_MSG(item) = msg; /* put it back as we found it */
2935 return((*here->nd_type->rcvmsg)(here, item, lasthook));
2936 }
2937 /* Fall through if rcvmsg not supported */
2938 default:
2939 TRAP_ERROR();
2940 error = EINVAL;
2941 }
2942 /*
2943 * Sometimes a generic message may be statically allocated
2944 * to avoid problems with allocating when in tight memory situations.
2945 * Don't free it if it is so.
2946 * I break them apart here, because erros may cause a free if the item
2947 * in which case we'd be doing it twice.
2948 * they are kept together above, to simplify freeing.
2949 */
2950 out:
2951 NG_RESPOND_MSG(error, here, item, resp);
2952 NG_FREE_MSG(msg);
2953 return (error);
2954 }
2955
2956 /************************************************************************
2957 Queue element get/free routines
2958 ************************************************************************/
2959
2960 uma_zone_t ng_qzone;
2961 uma_zone_t ng_qdzone;
2962 static int numthreads = 0; /* number of queue threads */
2963 static int maxalloc = 4096;/* limit the damage of a leak */
2964 static int maxdata = 4096; /* limit the damage of a DoS */
2965
2966 SYSCTL_INT(_net_graph, OID_AUTO, threads, CTLFLAG_RDTUN, &numthreads,
2967 0, "Number of queue processing threads");
2968 SYSCTL_INT(_net_graph, OID_AUTO, maxalloc, CTLFLAG_RDTUN, &maxalloc,
2969 0, "Maximum number of non-data queue items to allocate");
2970 SYSCTL_INT(_net_graph, OID_AUTO, maxdata, CTLFLAG_RDTUN, &maxdata,
2971 0, "Maximum number of data queue items to allocate");
2972
2973 #ifdef NETGRAPH_DEBUG
2974 static TAILQ_HEAD(, ng_item) ng_itemlist = TAILQ_HEAD_INITIALIZER(ng_itemlist);
2975 static int allocated; /* number of items malloc'd */
2976 #endif
2977
2978 /*
2979 * Get a queue entry.
2980 * This is usually called when a packet first enters netgraph.
2981 * By definition, this is usually from an interrupt, or from a user.
2982 * Users are not so important, but try be quick for the times that it's
2983 * an interrupt.
2984 */
2985 static __inline item_p
2986 ng_alloc_item(int type, int flags)
2987 {
2988 item_p item;
2989
2990 KASSERT(((type & ~NGQF_TYPE) == 0),
2991 ("%s: incorrect item type: %d", __func__, type));
2992
2993 item = uma_zalloc((type == NGQF_DATA) ? ng_qdzone : ng_qzone,
2994 ((flags & NG_WAITOK) ? M_WAITOK : M_NOWAIT) | M_ZERO);
2995
2996 if (item) {
2997 item->el_flags = type;
2998 #ifdef NETGRAPH_DEBUG
2999 mtx_lock(&ngq_mtx);
3000 TAILQ_INSERT_TAIL(&ng_itemlist, item, all);
3001 allocated++;
3002 mtx_unlock(&ngq_mtx);
3003 #endif
3004 }
3005
3006 return (item);
3007 }
3008
3009 /*
3010 * Release a queue entry
3011 */
3012 void
3013 ng_free_item(item_p item)
3014 {
3015 /*
3016 * The item may hold resources on it's own. We need to free
3017 * these before we can free the item. What they are depends upon
3018 * what kind of item it is. it is important that nodes zero
3019 * out pointers to resources that they remove from the item
3020 * or we release them again here.
3021 */
3022 switch (item->el_flags & NGQF_TYPE) {
3023 case NGQF_DATA:
3024 /* If we have an mbuf still attached.. */
3025 NG_FREE_M(_NGI_M(item));
3026 break;
3027 case NGQF_MESG:
3028 _NGI_RETADDR(item) = 0;
3029 NG_FREE_MSG(_NGI_MSG(item));
3030 break;
3031 case NGQF_FN:
3032 case NGQF_FN2:
3033 /* nothing to free really, */
3034 _NGI_FN(item) = NULL;
3035 _NGI_ARG1(item) = NULL;
3036 _NGI_ARG2(item) = 0;
3037 break;
3038 }
3039 /* If we still have a node or hook referenced... */
3040 _NGI_CLR_NODE(item);
3041 _NGI_CLR_HOOK(item);
3042
3043 #ifdef NETGRAPH_DEBUG
3044 mtx_lock(&ngq_mtx);
3045 TAILQ_REMOVE(&ng_itemlist, item, all);
3046 allocated--;
3047 mtx_unlock(&ngq_mtx);
3048 #endif
3049 uma_zfree(((item->el_flags & NGQF_TYPE) == NGQF_DATA) ?
3050 ng_qdzone : ng_qzone, item);
3051 }
3052
3053 /*
3054 * Change type of the queue entry.
3055 * Possibly reallocates it from another UMA zone.
3056 */
3057 static __inline item_p
3058 ng_realloc_item(item_p pitem, int type, int flags)
3059 {
3060 item_p item;
3061 int from, to;
3062
3063 KASSERT((pitem != NULL), ("%s: can't reallocate NULL", __func__));
3064 KASSERT(((type & ~NGQF_TYPE) == 0),
3065 ("%s: incorrect item type: %d", __func__, type));
3066
3067 from = ((pitem->el_flags & NGQF_TYPE) == NGQF_DATA);
3068 to = (type == NGQF_DATA);
3069 if (from != to) {
3070 /* If reallocation is required do it and copy item. */
3071 if ((item = ng_alloc_item(type, flags)) == NULL) {
3072 ng_free_item(pitem);
3073 return (NULL);
3074 }
3075 *item = *pitem;
3076 ng_free_item(pitem);
3077 } else
3078 item = pitem;
3079 item->el_flags = (item->el_flags & ~NGQF_TYPE) | type;
3080
3081 return (item);
3082 }
3083
3084 /************************************************************************
3085 Module routines
3086 ************************************************************************/
3087
3088 /*
3089 * Handle the loading/unloading of a netgraph node type module
3090 */
3091 int
3092 ng_mod_event(module_t mod, int event, void *data)
3093 {
3094 struct ng_type *const type = data;
3095 int error = 0;
3096
3097 switch (event) {
3098 case MOD_LOAD:
3099
3100 /* Register new netgraph node type */
3101 if ((error = ng_newtype(type)) != 0)
3102 break;
3103
3104 /* Call type specific code */
3105 if (type->mod_event != NULL)
3106 if ((error = (*type->mod_event)(mod, event, data))) {
3107 TYPELIST_WLOCK();
3108 type->refs--; /* undo it */
3109 LIST_REMOVE(type, types);
3110 TYPELIST_WUNLOCK();
3111 }
3112 break;
3113
3114 case MOD_UNLOAD:
3115 if (type->refs > 1) { /* make sure no nodes exist! */
3116 error = EBUSY;
3117 } else {
3118 if (type->refs == 0) /* failed load, nothing to undo */
3119 break;
3120 if (type->mod_event != NULL) { /* check with type */
3121 error = (*type->mod_event)(mod, event, data);
3122 if (error != 0) /* type refuses.. */
3123 break;
3124 }
3125 TYPELIST_WLOCK();
3126 LIST_REMOVE(type, types);
3127 TYPELIST_WUNLOCK();
3128 }
3129 break;
3130
3131 default:
3132 if (type->mod_event != NULL)
3133 error = (*type->mod_event)(mod, event, data);
3134 else
3135 error = EOPNOTSUPP; /* XXX ? */
3136 break;
3137 }
3138 return (error);
3139 }
3140
3141 static void
3142 vnet_netgraph_init(const void *unused __unused)
3143 {
3144
3145 /* We start with small hashes, but they can grow. */
3146 V_ng_ID_hash = hashinit(16, M_NETGRAPH_NODE, &V_ng_ID_hmask);
3147 V_ng_name_hash = hashinit(16, M_NETGRAPH_NODE, &V_ng_name_hmask);
3148 }
3149 VNET_SYSINIT(vnet_netgraph_init, SI_SUB_NETGRAPH, SI_ORDER_FIRST,
3150 vnet_netgraph_init, NULL);
3151
3152 #ifdef VIMAGE
3153 static void
3154 vnet_netgraph_uninit(const void *unused __unused)
3155 {
3156 node_p node = NULL, last_killed = NULL;
3157 int i;
3158
3159 do {
3160 /* Find a node to kill */
3161 IDHASH_RLOCK();
3162 for (i = 0; i <= V_ng_ID_hmask; i++) {
3163 LIST_FOREACH(node, &V_ng_ID_hash[i], nd_idnodes) {
3164 if (node != &ng_deadnode) {
3165 NG_NODE_REF(node);
3166 break;
3167 }
3168 }
3169 if (node != NULL)
3170 break;
3171 }
3172 IDHASH_RUNLOCK();
3173
3174 /* Attempt to kill it only if it is a regular node */
3175 if (node != NULL) {
3176 if (node == last_killed) {
3177 /* This should never happen */
3178 printf("ng node %s needs NGF_REALLY_DIE\n",
3179 node->nd_name);
3180 if (node->nd_flags & NGF_REALLY_DIE)
3181 panic("ng node %s won't die",
3182 node->nd_name);
3183 node->nd_flags |= NGF_REALLY_DIE;
3184 }
3185 ng_rmnode(node, NULL, NULL, 0);
3186 NG_NODE_UNREF(node);
3187 last_killed = node;
3188 }
3189 } while (node != NULL);
3190
3191 hashdestroy(V_ng_name_hash, M_NETGRAPH_NODE, V_ng_name_hmask);
3192 hashdestroy(V_ng_ID_hash, M_NETGRAPH_NODE, V_ng_ID_hmask);
3193 }
3194 VNET_SYSUNINIT(vnet_netgraph_uninit, SI_SUB_NETGRAPH, SI_ORDER_FIRST,
3195 vnet_netgraph_uninit, NULL);
3196 #endif /* VIMAGE */
3197
3198 /*
3199 * Handle loading and unloading for this code.
3200 * The only thing we need to link into is the NETISR strucure.
3201 */
3202 static int
3203 ngb_mod_event(module_t mod, int event, void *data)
3204 {
3205 struct proc *p;
3206 struct thread *td;
3207 int i, error = 0;
3208
3209 switch (event) {
3210 case MOD_LOAD:
3211 /* Initialize everything. */
3212 NG_WORKLIST_LOCK_INIT();
3213 rw_init(&ng_typelist_lock, "netgraph types");
3214 rw_init(&ng_idhash_lock, "netgraph idhash");
3215 rw_init(&ng_namehash_lock, "netgraph namehash");
3216 rw_init(&ng_topo_lock, "netgraph topology mutex");
3217 #ifdef NETGRAPH_DEBUG
3218 mtx_init(&ng_nodelist_mtx, "netgraph nodelist mutex", NULL,
3219 MTX_DEF);
3220 mtx_init(&ngq_mtx, "netgraph item list mutex", NULL,
3221 MTX_DEF);
3222 #endif
3223 ng_qzone = uma_zcreate("NetGraph items", sizeof(struct ng_item),
3224 NULL, NULL, NULL, NULL, UMA_ALIGN_CACHE, 0);
3225 uma_zone_set_max(ng_qzone, maxalloc);
3226 ng_qdzone = uma_zcreate("NetGraph data items",
3227 sizeof(struct ng_item), NULL, NULL, NULL, NULL,
3228 UMA_ALIGN_CACHE, 0);
3229 uma_zone_set_max(ng_qdzone, maxdata);
3230 /* Autoconfigure number of threads. */
3231 if (numthreads <= 0)
3232 numthreads = mp_ncpus;
3233 /* Create threads. */
3234 p = NULL; /* start with no process */
3235 for (i = 0; i < numthreads; i++) {
3236 if (kproc_kthread_add(ngthread, NULL, &p, &td,
3237 RFHIGHPID, 0, "ng_queue", "ng_queue%d", i)) {
3238 numthreads = i;
3239 break;
3240 }
3241 }
3242 break;
3243 case MOD_UNLOAD:
3244 /* You can't unload it because an interface may be using it. */
3245 error = EBUSY;
3246 break;
3247 default:
3248 error = EOPNOTSUPP;
3249 break;
3250 }
3251 return (error);
3252 }
3253
3254 static moduledata_t netgraph_mod = {
3255 "netgraph",
3256 ngb_mod_event,
3257 (NULL)
3258 };
3259 DECLARE_MODULE(netgraph, netgraph_mod, SI_SUB_NETGRAPH, SI_ORDER_FIRST);
3260 SYSCTL_NODE(_net, OID_AUTO, graph, CTLFLAG_RW, 0, "netgraph Family");
3261 SYSCTL_INT(_net_graph, OID_AUTO, abi_version, CTLFLAG_RD, SYSCTL_NULL_INT_PTR, NG_ABI_VERSION,"");
3262 SYSCTL_INT(_net_graph, OID_AUTO, msg_version, CTLFLAG_RD, SYSCTL_NULL_INT_PTR, NG_VERSION, "");
3263
3264 #ifdef NETGRAPH_DEBUG
3265 void
3266 dumphook (hook_p hook, char *file, int line)
3267 {
3268 printf("hook: name %s, %d refs, Last touched:\n",
3269 _NG_HOOK_NAME(hook), hook->hk_refs);
3270 printf(" Last active @ %s, line %d\n",
3271 hook->lastfile, hook->lastline);
3272 if (line) {
3273 printf(" problem discovered at file %s, line %d\n", file, line);
3274 #ifdef KDB
3275 kdb_backtrace();
3276 #endif
3277 }
3278 }
3279
3280 void
3281 dumpnode(node_p node, char *file, int line)
3282 {
3283 printf("node: ID [%x]: type '%s', %d hooks, flags 0x%x, %d refs, %s:\n",
3284 _NG_NODE_ID(node), node->nd_type->name,
3285 node->nd_numhooks, node->nd_flags,
3286 node->nd_refs, node->nd_name);
3287 printf(" Last active @ %s, line %d\n",
3288 node->lastfile, node->lastline);
3289 if (line) {
3290 printf(" problem discovered at file %s, line %d\n", file, line);
3291 #ifdef KDB
3292 kdb_backtrace();
3293 #endif
3294 }
3295 }
3296
3297 void
3298 dumpitem(item_p item, char *file, int line)
3299 {
3300 printf(" ACTIVE item, last used at %s, line %d",
3301 item->lastfile, item->lastline);
3302 switch(item->el_flags & NGQF_TYPE) {
3303 case NGQF_DATA:
3304 printf(" - [data]\n");
3305 break;
3306 case NGQF_MESG:
3307 printf(" - retaddr[%d]:\n", _NGI_RETADDR(item));
3308 break;
3309 case NGQF_FN:
3310 printf(" - fn@%p (%p, %p, %p, %d (%x))\n",
3311 _NGI_FN(item),
3312 _NGI_NODE(item),
3313 _NGI_HOOK(item),
3314 item->body.fn.fn_arg1,
3315 item->body.fn.fn_arg2,
3316 item->body.fn.fn_arg2);
3317 break;
3318 case NGQF_FN2:
3319 printf(" - fn2@%p (%p, %p, %p, %d (%x))\n",
3320 _NGI_FN2(item),
3321 _NGI_NODE(item),
3322 _NGI_HOOK(item),
3323 item->body.fn.fn_arg1,
3324 item->body.fn.fn_arg2,
3325 item->body.fn.fn_arg2);
3326 break;
3327 }
3328 if (line) {
3329 printf(" problem discovered at file %s, line %d\n", file, line);
3330 if (_NGI_NODE(item)) {
3331 printf("node %p ([%x])\n",
3332 _NGI_NODE(item), ng_node2ID(_NGI_NODE(item)));
3333 }
3334 }
3335 }
3336
3337 static void
3338 ng_dumpitems(void)
3339 {
3340 item_p item;
3341 int i = 1;
3342 TAILQ_FOREACH(item, &ng_itemlist, all) {
3343 printf("[%d] ", i++);
3344 dumpitem(item, NULL, 0);
3345 }
3346 }
3347
3348 static void
3349 ng_dumpnodes(void)
3350 {
3351 node_p node;
3352 int i = 1;
3353 mtx_lock(&ng_nodelist_mtx);
3354 SLIST_FOREACH(node, &ng_allnodes, nd_all) {
3355 printf("[%d] ", i++);
3356 dumpnode(node, NULL, 0);
3357 }
3358 mtx_unlock(&ng_nodelist_mtx);
3359 }
3360
3361 static void
3362 ng_dumphooks(void)
3363 {
3364 hook_p hook;
3365 int i = 1;
3366 mtx_lock(&ng_nodelist_mtx);
3367 SLIST_FOREACH(hook, &ng_allhooks, hk_all) {
3368 printf("[%d] ", i++);
3369 dumphook(hook, NULL, 0);
3370 }
3371 mtx_unlock(&ng_nodelist_mtx);
3372 }
3373
3374 static int
3375 sysctl_debug_ng_dump_items(SYSCTL_HANDLER_ARGS)
3376 {
3377 int error;
3378 int val;
3379 int i;
3380
3381 val = allocated;
3382 i = 1;
3383 error = sysctl_handle_int(oidp, &val, 0, req);
3384 if (error != 0 || req->newptr == NULL)
3385 return (error);
3386 if (val == 42) {
3387 ng_dumpitems();
3388 ng_dumpnodes();
3389 ng_dumphooks();
3390 }
3391 return (0);
3392 }
3393
3394 SYSCTL_PROC(_debug, OID_AUTO, ng_dump_items, CTLTYPE_INT | CTLFLAG_RW,
3395 0, sizeof(int), sysctl_debug_ng_dump_items, "I", "Number of allocated items");
3396 #endif /* NETGRAPH_DEBUG */
3397
3398 /***********************************************************************
3399 * Worklist routines
3400 **********************************************************************/
3401 /*
3402 * Pick a node off the list of nodes with work,
3403 * try get an item to process off it. Remove the node from the list.
3404 */
3405 static void
3406 ngthread(void *arg)
3407 {
3408 for (;;) {
3409 node_p node;
3410
3411 /* Get node from the worklist. */
3412 NG_WORKLIST_LOCK();
3413 while ((node = STAILQ_FIRST(&ng_worklist)) == NULL)
3414 NG_WORKLIST_SLEEP();
3415 STAILQ_REMOVE_HEAD(&ng_worklist, nd_input_queue.q_work);
3416 NG_WORKLIST_UNLOCK();
3417 CURVNET_SET(node->nd_vnet);
3418 CTR3(KTR_NET, "%20s: node [%x] (%p) taken off worklist",
3419 __func__, node->nd_ID, node);
3420 /*
3421 * We have the node. We also take over the reference
3422 * that the list had on it.
3423 * Now process as much as you can, until it won't
3424 * let you have another item off the queue.
3425 * All this time, keep the reference
3426 * that lets us be sure that the node still exists.
3427 * Let the reference go at the last minute.
3428 */
3429 for (;;) {
3430 item_p item;
3431 int rw;
3432
3433 NG_QUEUE_LOCK(&node->nd_input_queue);
3434 item = ng_dequeue(node, &rw);
3435 if (item == NULL) {
3436 node->nd_input_queue.q_flags2 &= ~NGQ2_WORKQ;
3437 NG_QUEUE_UNLOCK(&node->nd_input_queue);
3438 break; /* go look for another node */
3439 } else {
3440 NG_QUEUE_UNLOCK(&node->nd_input_queue);
3441 NGI_GET_NODE(item, node); /* zaps stored node */
3442 ng_apply_item(node, item, rw);
3443 NG_NODE_UNREF(node);
3444 }
3445 }
3446 NG_NODE_UNREF(node);
3447 CURVNET_RESTORE();
3448 }
3449 }
3450
3451 /*
3452 * XXX
3453 * It's posible that a debugging NG_NODE_REF may need
3454 * to be outside the mutex zone
3455 */
3456 static void
3457 ng_worklist_add(node_p node)
3458 {
3459
3460 mtx_assert(&node->nd_input_queue.q_mtx, MA_OWNED);
3461
3462 if ((node->nd_input_queue.q_flags2 & NGQ2_WORKQ) == 0) {
3463 /*
3464 * If we are not already on the work queue,
3465 * then put us on.
3466 */
3467 node->nd_input_queue.q_flags2 |= NGQ2_WORKQ;
3468 NG_NODE_REF(node); /* XXX safe in mutex? */
3469 NG_WORKLIST_LOCK();
3470 STAILQ_INSERT_TAIL(&ng_worklist, node, nd_input_queue.q_work);
3471 NG_WORKLIST_UNLOCK();
3472 CTR3(KTR_NET, "%20s: node [%x] (%p) put on worklist", __func__,
3473 node->nd_ID, node);
3474 NG_WORKLIST_WAKEUP();
3475 } else {
3476 CTR3(KTR_NET, "%20s: node [%x] (%p) already on worklist",
3477 __func__, node->nd_ID, node);
3478 }
3479 }
3480
3481 /***********************************************************************
3482 * Externally useable functions to set up a queue item ready for sending
3483 ***********************************************************************/
3484
3485 #ifdef NETGRAPH_DEBUG
3486 #define ITEM_DEBUG_CHECKS \
3487 do { \
3488 if (NGI_NODE(item) ) { \
3489 printf("item already has node"); \
3490 kdb_enter(KDB_WHY_NETGRAPH, "has node"); \
3491 NGI_CLR_NODE(item); \
3492 } \
3493 if (NGI_HOOK(item) ) { \
3494 printf("item already has hook"); \
3495 kdb_enter(KDB_WHY_NETGRAPH, "has hook"); \
3496 NGI_CLR_HOOK(item); \
3497 } \
3498 } while (0)
3499 #else
3500 #define ITEM_DEBUG_CHECKS
3501 #endif
3502
3503 /*
3504 * Put mbuf into the item.
3505 * Hook and node references will be removed when the item is dequeued.
3506 * (or equivalent)
3507 * (XXX) Unsafe because no reference held by peer on remote node.
3508 * remote node might go away in this timescale.
3509 * We know the hooks can't go away because that would require getting
3510 * a writer item on both nodes and we must have at least a reader
3511 * here to be able to do this.
3512 * Note that the hook loaded is the REMOTE hook.
3513 *
3514 * This is possibly in the critical path for new data.
3515 */
3516 item_p
3517 ng_package_data(struct mbuf *m, int flags)
3518 {
3519 item_p item;
3520
3521 if ((item = ng_alloc_item(NGQF_DATA, flags)) == NULL) {
3522 NG_FREE_M(m);
3523 return (NULL);
3524 }
3525 ITEM_DEBUG_CHECKS;
3526 item->el_flags |= NGQF_READER;
3527 NGI_M(item) = m;
3528 return (item);
3529 }
3530
3531 /*
3532 * Allocate a queue item and put items into it..
3533 * Evaluate the address as this will be needed to queue it and
3534 * to work out what some of the fields should be.
3535 * Hook and node references will be removed when the item is dequeued.
3536 * (or equivalent)
3537 */
3538 item_p
3539 ng_package_msg(struct ng_mesg *msg, int flags)
3540 {
3541 item_p item;
3542
3543 if ((item = ng_alloc_item(NGQF_MESG, flags)) == NULL) {
3544 NG_FREE_MSG(msg);
3545 return (NULL);
3546 }
3547 ITEM_DEBUG_CHECKS;
3548 /* Messages items count as writers unless explicitly exempted. */
3549 if (msg->header.cmd & NGM_READONLY)
3550 item->el_flags |= NGQF_READER;
3551 else
3552 item->el_flags |= NGQF_WRITER;
3553 /*
3554 * Set the current lasthook into the queue item
3555 */
3556 NGI_MSG(item) = msg;
3557 NGI_RETADDR(item) = 0;
3558 return (item);
3559 }
3560
3561 #define SET_RETADDR(item, here, retaddr) \
3562 do { /* Data or fn items don't have retaddrs */ \
3563 if ((item->el_flags & NGQF_TYPE) == NGQF_MESG) { \
3564 if (retaddr) { \
3565 NGI_RETADDR(item) = retaddr; \
3566 } else { \
3567 /* \
3568 * The old return address should be ok. \
3569 * If there isn't one, use the address \
3570 * here. \
3571 */ \
3572 if (NGI_RETADDR(item) == 0) { \
3573 NGI_RETADDR(item) \
3574 = ng_node2ID(here); \
3575 } \
3576 } \
3577 } \
3578 } while (0)
3579
3580 int
3581 ng_address_hook(node_p here, item_p item, hook_p hook, ng_ID_t retaddr)
3582 {
3583 hook_p peer;
3584 node_p peernode;
3585 ITEM_DEBUG_CHECKS;
3586 /*
3587 * Quick sanity check..
3588 * Since a hook holds a reference on it's node, once we know
3589 * that the peer is still connected (even if invalid,) we know
3590 * that the peer node is present, though maybe invalid.
3591 */
3592 TOPOLOGY_RLOCK();
3593 if ((hook == NULL) || NG_HOOK_NOT_VALID(hook) ||
3594 NG_HOOK_NOT_VALID(peer = NG_HOOK_PEER(hook)) ||
3595 NG_NODE_NOT_VALID(peernode = NG_PEER_NODE(hook))) {
3596 NG_FREE_ITEM(item);
3597 TRAP_ERROR();
3598 TOPOLOGY_RUNLOCK();
3599 return (ENETDOWN);
3600 }
3601
3602 /*
3603 * Transfer our interest to the other (peer) end.
3604 */
3605 NG_HOOK_REF(peer);
3606 NG_NODE_REF(peernode);
3607 NGI_SET_HOOK(item, peer);
3608 NGI_SET_NODE(item, peernode);
3609 SET_RETADDR(item, here, retaddr);
3610
3611 TOPOLOGY_RUNLOCK();
3612
3613 return (0);
3614 }
3615
3616 int
3617 ng_address_path(node_p here, item_p item, const char *address, ng_ID_t retaddr)
3618 {
3619 node_p dest = NULL;
3620 hook_p hook = NULL;
3621 int error;
3622
3623 ITEM_DEBUG_CHECKS;
3624 /*
3625 * Note that ng_path2noderef increments the reference count
3626 * on the node for us if it finds one. So we don't have to.
3627 */
3628 error = ng_path2noderef(here, address, &dest, &hook);
3629 if (error) {
3630 NG_FREE_ITEM(item);
3631 return (error);
3632 }
3633 NGI_SET_NODE(item, dest);
3634 if (hook)
3635 NGI_SET_HOOK(item, hook);
3636
3637 SET_RETADDR(item, here, retaddr);
3638 return (0);
3639 }
3640
3641 int
3642 ng_address_ID(node_p here, item_p item, ng_ID_t ID, ng_ID_t retaddr)
3643 {
3644 node_p dest;
3645
3646 ITEM_DEBUG_CHECKS;
3647 /*
3648 * Find the target node.
3649 */
3650 dest = ng_ID2noderef(ID); /* GETS REFERENCE! */
3651 if (dest == NULL) {
3652 NG_FREE_ITEM(item);
3653 TRAP_ERROR();
3654 return(EINVAL);
3655 }
3656 /* Fill out the contents */
3657 NGI_SET_NODE(item, dest);
3658 NGI_CLR_HOOK(item);
3659 SET_RETADDR(item, here, retaddr);
3660 return (0);
3661 }
3662
3663 /*
3664 * special case to send a message to self (e.g. destroy node)
3665 * Possibly indicate an arrival hook too.
3666 * Useful for removing that hook :-)
3667 */
3668 item_p
3669 ng_package_msg_self(node_p here, hook_p hook, struct ng_mesg *msg)
3670 {
3671 item_p item;
3672
3673 /*
3674 * Find the target node.
3675 * If there is a HOOK argument, then use that in preference
3676 * to the address.
3677 */
3678 if ((item = ng_alloc_item(NGQF_MESG, NG_NOFLAGS)) == NULL) {
3679 NG_FREE_MSG(msg);
3680 return (NULL);
3681 }
3682
3683 /* Fill out the contents */
3684 item->el_flags |= NGQF_WRITER;
3685 NG_NODE_REF(here);
3686 NGI_SET_NODE(item, here);
3687 if (hook) {
3688 NG_HOOK_REF(hook);
3689 NGI_SET_HOOK(item, hook);
3690 }
3691 NGI_MSG(item) = msg;
3692 NGI_RETADDR(item) = ng_node2ID(here);
3693 return (item);
3694 }
3695
3696 /*
3697 * Send ng_item_fn function call to the specified node.
3698 */
3699
3700 int
3701 ng_send_fn(node_p node, hook_p hook, ng_item_fn *fn, void * arg1, int arg2)
3702 {
3703
3704 return ng_send_fn1(node, hook, fn, arg1, arg2, NG_NOFLAGS);
3705 }
3706
3707 int
3708 ng_send_fn1(node_p node, hook_p hook, ng_item_fn *fn, void * arg1, int arg2,
3709 int flags)
3710 {
3711 item_p item;
3712
3713 if ((item = ng_alloc_item(NGQF_FN, flags)) == NULL) {
3714 return (ENOMEM);
3715 }
3716 item->el_flags |= NGQF_WRITER;
3717 NG_NODE_REF(node); /* and one for the item */
3718 NGI_SET_NODE(item, node);
3719 if (hook) {
3720 NG_HOOK_REF(hook);
3721 NGI_SET_HOOK(item, hook);
3722 }
3723 NGI_FN(item) = fn;
3724 NGI_ARG1(item) = arg1;
3725 NGI_ARG2(item) = arg2;
3726 return(ng_snd_item(item, flags));
3727 }
3728
3729 /*
3730 * Send ng_item_fn2 function call to the specified node.
3731 *
3732 * If an optional pitem parameter is supplied, its apply
3733 * callback will be copied to the new item. If also NG_REUSE_ITEM
3734 * flag is set, no new item will be allocated, but pitem will
3735 * be used.
3736 */
3737 int
3738 ng_send_fn2(node_p node, hook_p hook, item_p pitem, ng_item_fn2 *fn, void *arg1,
3739 int arg2, int flags)
3740 {
3741 item_p item;
3742
3743 KASSERT((pitem != NULL || (flags & NG_REUSE_ITEM) == 0),
3744 ("%s: NG_REUSE_ITEM but no pitem", __func__));
3745
3746 /*
3747 * Allocate a new item if no supplied or
3748 * if we can't use supplied one.
3749 */
3750 if (pitem == NULL || (flags & NG_REUSE_ITEM) == 0) {
3751 if ((item = ng_alloc_item(NGQF_FN2, flags)) == NULL)
3752 return (ENOMEM);
3753 if (pitem != NULL)
3754 item->apply = pitem->apply;
3755 } else {
3756 if ((item = ng_realloc_item(pitem, NGQF_FN2, flags)) == NULL)
3757 return (ENOMEM);
3758 }
3759
3760 item->el_flags = (item->el_flags & ~NGQF_RW) | NGQF_WRITER;
3761 NG_NODE_REF(node); /* and one for the item */
3762 NGI_SET_NODE(item, node);
3763 if (hook) {
3764 NG_HOOK_REF(hook);
3765 NGI_SET_HOOK(item, hook);
3766 }
3767 NGI_FN2(item) = fn;
3768 NGI_ARG1(item) = arg1;
3769 NGI_ARG2(item) = arg2;
3770 return(ng_snd_item(item, flags));
3771 }
3772
3773 /*
3774 * Official timeout routines for Netgraph nodes.
3775 */
3776 static void
3777 ng_callout_trampoline(void *arg)
3778 {
3779 item_p item = arg;
3780
3781 CURVNET_SET(NGI_NODE(item)->nd_vnet);
3782 ng_snd_item(item, 0);
3783 CURVNET_RESTORE();
3784 }
3785
3786 int
3787 ng_callout(struct callout *c, node_p node, hook_p hook, int ticks,
3788 ng_item_fn *fn, void * arg1, int arg2)
3789 {
3790 item_p item, oitem;
3791
3792 if ((item = ng_alloc_item(NGQF_FN, NG_NOFLAGS)) == NULL)
3793 return (ENOMEM);
3794
3795 item->el_flags |= NGQF_WRITER;
3796 NG_NODE_REF(node); /* and one for the item */
3797 NGI_SET_NODE(item, node);
3798 if (hook) {
3799 NG_HOOK_REF(hook);
3800 NGI_SET_HOOK(item, hook);
3801 }
3802 NGI_FN(item) = fn;
3803 NGI_ARG1(item) = arg1;
3804 NGI_ARG2(item) = arg2;
3805 oitem = c->c_arg;
3806 if (callout_reset(c, ticks, &ng_callout_trampoline, item) == 1 &&
3807 oitem != NULL)
3808 NG_FREE_ITEM(oitem);
3809 return (0);
3810 }
3811
3812 /* A special modified version of untimeout() */
3813 int
3814 ng_uncallout(struct callout *c, node_p node)
3815 {
3816 item_p item;
3817 int rval;
3818
3819 KASSERT(c != NULL, ("ng_uncallout: NULL callout"));
3820 KASSERT(node != NULL, ("ng_uncallout: NULL node"));
3821
3822 rval = callout_stop(c);
3823 item = c->c_arg;
3824 /* Do an extra check */
3825 if ((rval > 0) && (c->c_func == &ng_callout_trampoline) &&
3826 (item != NULL) && (NGI_NODE(item) == node)) {
3827 /*
3828 * We successfully removed it from the queue before it ran
3829 * So now we need to unreference everything that was
3830 * given extra references. (NG_FREE_ITEM does this).
3831 */
3832 NG_FREE_ITEM(item);
3833 }
3834 c->c_arg = NULL;
3835
3836 /*
3837 * Callers only want to know if the callout was cancelled and
3838 * not draining or stopped.
3839 */
3840 return (rval > 0);
3841 }
3842
3843 /*
3844 * Set the address, if none given, give the node here.
3845 */
3846 void
3847 ng_replace_retaddr(node_p here, item_p item, ng_ID_t retaddr)
3848 {
3849 if (retaddr) {
3850 NGI_RETADDR(item) = retaddr;
3851 } else {
3852 /*
3853 * The old return address should be ok.
3854 * If there isn't one, use the address here.
3855 */
3856 NGI_RETADDR(item) = ng_node2ID(here);
3857 }
3858 }
Cache object: 24fbef1968189173597266debb84acd6
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