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: releng/11.2/sys/netgraph/ng_base.c 333615 2018-05-14 22:56:41Z sbruno $
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 /* Check the name is valid */
858 for (i = 0; i < NG_NODESIZ; i++) {
859 if (name[i] == '\0' || name[i] == '.' || name[i] == ':')
860 break;
861 }
862 if (i == 0 || name[i] != '\0') {
863 TRAP_ERROR();
864 return (EINVAL);
865 }
866 if (ng_decodeidname(name) != 0) { /* valid IDs not allowed here */
867 TRAP_ERROR();
868 return (EINVAL);
869 }
870
871 NAMEHASH_WLOCK();
872 if (V_ng_named_nodes * 2 > V_ng_name_hmask)
873 ng_name_rehash();
874
875 hash = hash32_str(name, HASHINIT) & V_ng_name_hmask;
876 /* Check the name isn't already being used. */
877 LIST_FOREACH(node2, &V_ng_name_hash[hash], nd_nodes)
878 if (NG_NODE_IS_VALID(node2) &&
879 (strcmp(NG_NODE_NAME(node2), name) == 0)) {
880 NAMEHASH_WUNLOCK();
881 return (EADDRINUSE);
882 }
883
884 if (NG_NODE_HAS_NAME(node))
885 LIST_REMOVE(node, nd_nodes);
886 else
887 V_ng_named_nodes++;
888 /* Copy it. */
889 strlcpy(NG_NODE_NAME(node), name, NG_NODESIZ);
890 /* Update name hash. */
891 LIST_INSERT_HEAD(&V_ng_name_hash[hash], node, nd_nodes);
892 NAMEHASH_WUNLOCK();
893
894 return (0);
895 }
896
897 /*
898 * Find a node by absolute name. The name should NOT end with ':'
899 * The name "." means "this node" and "[xxx]" means "the node
900 * with ID (ie, at address) xxx".
901 *
902 * Returns the node if found, else NULL.
903 * Eventually should add something faster than a sequential search.
904 * Note it acquires a reference on the node so you can be sure it's still
905 * there.
906 */
907 node_p
908 ng_name2noderef(node_p here, const char *name)
909 {
910 node_p node;
911 ng_ID_t temp;
912 int hash;
913
914 /* "." means "this node" */
915 if (strcmp(name, ".") == 0) {
916 NG_NODE_REF(here);
917 return(here);
918 }
919
920 /* Check for name-by-ID */
921 if ((temp = ng_decodeidname(name)) != 0) {
922 return (ng_ID2noderef(temp));
923 }
924
925 /* Find node by name. */
926 hash = hash32_str(name, HASHINIT) & V_ng_name_hmask;
927 NAMEHASH_RLOCK();
928 LIST_FOREACH(node, &V_ng_name_hash[hash], nd_nodes)
929 if (NG_NODE_IS_VALID(node) &&
930 (strcmp(NG_NODE_NAME(node), name) == 0)) {
931 NG_NODE_REF(node);
932 break;
933 }
934 NAMEHASH_RUNLOCK();
935
936 return (node);
937 }
938
939 /*
940 * Decode an ID name, eg. "[f03034de]". Returns 0 if the
941 * string is not valid, otherwise returns the value.
942 */
943 static ng_ID_t
944 ng_decodeidname(const char *name)
945 {
946 const int len = strlen(name);
947 char *eptr;
948 u_long val;
949
950 /* Check for proper length, brackets, no leading junk */
951 if ((len < 3) || (name[0] != '[') || (name[len - 1] != ']') ||
952 (!isxdigit(name[1])))
953 return ((ng_ID_t)0);
954
955 /* Decode number */
956 val = strtoul(name + 1, &eptr, 16);
957 if ((eptr - name != len - 1) || (val == ULONG_MAX) || (val == 0))
958 return ((ng_ID_t)0);
959
960 return ((ng_ID_t)val);
961 }
962
963 /*
964 * Remove a name from a node. This should only be called
965 * when shutting down and removing the node.
966 */
967 void
968 ng_unname(node_p node)
969 {
970 }
971
972 /*
973 * Allocate a bigger name hash.
974 */
975 static void
976 ng_name_rehash()
977 {
978 struct nodehash *new;
979 uint32_t hash;
980 u_long hmask;
981 node_p node, node2;
982 int i;
983
984 new = hashinit_flags((V_ng_name_hmask + 1) * 2, M_NETGRAPH_NODE, &hmask,
985 HASH_NOWAIT);
986 if (new == NULL)
987 return;
988
989 for (i = 0; i <= V_ng_name_hmask; i++)
990 LIST_FOREACH_SAFE(node, &V_ng_name_hash[i], nd_nodes, node2) {
991 #ifdef INVARIANTS
992 LIST_REMOVE(node, nd_nodes);
993 #endif
994 hash = hash32_str(NG_NODE_NAME(node), HASHINIT) & hmask;
995 LIST_INSERT_HEAD(&new[hash], node, nd_nodes);
996 }
997
998 hashdestroy(V_ng_name_hash, M_NETGRAPH_NODE, V_ng_name_hmask);
999 V_ng_name_hash = new;
1000 V_ng_name_hmask = hmask;
1001 }
1002
1003 /*
1004 * Allocate a bigger ID hash.
1005 */
1006 static void
1007 ng_ID_rehash()
1008 {
1009 struct nodehash *new;
1010 uint32_t hash;
1011 u_long hmask;
1012 node_p node, node2;
1013 int i;
1014
1015 new = hashinit_flags((V_ng_ID_hmask + 1) * 2, M_NETGRAPH_NODE, &hmask,
1016 HASH_NOWAIT);
1017 if (new == NULL)
1018 return;
1019
1020 for (i = 0; i <= V_ng_ID_hmask; i++)
1021 LIST_FOREACH_SAFE(node, &V_ng_ID_hash[i], nd_idnodes, node2) {
1022 #ifdef INVARIANTS
1023 LIST_REMOVE(node, nd_idnodes);
1024 #endif
1025 hash = (node->nd_ID % (hmask + 1));
1026 LIST_INSERT_HEAD(&new[hash], node, nd_idnodes);
1027 }
1028
1029 hashdestroy(V_ng_ID_hash, M_NETGRAPH_NODE, V_ng_name_hmask);
1030 V_ng_ID_hash = new;
1031 V_ng_ID_hmask = hmask;
1032 }
1033
1034 /************************************************************************
1035 Hook routines
1036 Names are not optional. Hooks are always connected, except for a
1037 brief moment within these routines. On invalidation or during creation
1038 they are connected to the 'dead' hook.
1039 ************************************************************************/
1040
1041 /*
1042 * Remove a hook reference
1043 */
1044 void
1045 ng_unref_hook(hook_p hook)
1046 {
1047
1048 if (hook == &ng_deadhook)
1049 return;
1050
1051 if (refcount_release(&hook->hk_refs)) { /* we were the last */
1052 if (_NG_HOOK_NODE(hook)) /* it'll probably be ng_deadnode */
1053 _NG_NODE_UNREF((_NG_HOOK_NODE(hook)));
1054 NG_FREE_HOOK(hook);
1055 }
1056 }
1057
1058 /*
1059 * Add an unconnected hook to a node. Only used internally.
1060 * Assumes node is locked. (XXX not yet true )
1061 */
1062 static int
1063 ng_add_hook(node_p node, const char *name, hook_p *hookp)
1064 {
1065 hook_p hook;
1066 int error = 0;
1067
1068 /* Check that the given name is good */
1069 if (name == NULL) {
1070 TRAP_ERROR();
1071 return (EINVAL);
1072 }
1073 if (ng_findhook(node, name) != NULL) {
1074 TRAP_ERROR();
1075 return (EEXIST);
1076 }
1077
1078 /* Allocate the hook and link it up */
1079 NG_ALLOC_HOOK(hook);
1080 if (hook == NULL) {
1081 TRAP_ERROR();
1082 return (ENOMEM);
1083 }
1084 hook->hk_refs = 1; /* add a reference for us to return */
1085 hook->hk_flags = HK_INVALID;
1086 hook->hk_peer = &ng_deadhook; /* start off this way */
1087 hook->hk_node = node;
1088 NG_NODE_REF(node); /* each hook counts as a reference */
1089
1090 /* Set hook name */
1091 strlcpy(NG_HOOK_NAME(hook), name, NG_HOOKSIZ);
1092
1093 /*
1094 * Check if the node type code has something to say about it
1095 * If it fails, the unref of the hook will also unref the node.
1096 */
1097 if (node->nd_type->newhook != NULL) {
1098 if ((error = (*node->nd_type->newhook)(node, hook, name))) {
1099 NG_HOOK_UNREF(hook); /* this frees the hook */
1100 return (error);
1101 }
1102 }
1103 /*
1104 * The 'type' agrees so far, so go ahead and link it in.
1105 * We'll ask again later when we actually connect the hooks.
1106 */
1107 LIST_INSERT_HEAD(&node->nd_hooks, hook, hk_hooks);
1108 node->nd_numhooks++;
1109 NG_HOOK_REF(hook); /* one for the node */
1110
1111 if (hookp)
1112 *hookp = hook;
1113 return (0);
1114 }
1115
1116 /*
1117 * Find a hook
1118 *
1119 * Node types may supply their own optimized routines for finding
1120 * hooks. If none is supplied, we just do a linear search.
1121 * XXX Possibly we should add a reference to the hook?
1122 */
1123 hook_p
1124 ng_findhook(node_p node, const char *name)
1125 {
1126 hook_p hook;
1127
1128 if (node->nd_type->findhook != NULL)
1129 return (*node->nd_type->findhook)(node, name);
1130 LIST_FOREACH(hook, &node->nd_hooks, hk_hooks) {
1131 if (NG_HOOK_IS_VALID(hook) &&
1132 (strcmp(NG_HOOK_NAME(hook), name) == 0))
1133 return (hook);
1134 }
1135 return (NULL);
1136 }
1137
1138 /*
1139 * Destroy a hook
1140 *
1141 * As hooks are always attached, this really destroys two hooks.
1142 * The one given, and the one attached to it. Disconnect the hooks
1143 * from each other first. We reconnect the peer hook to the 'dead'
1144 * hook so that it can still exist after we depart. We then
1145 * send the peer its own destroy message. This ensures that we only
1146 * interact with the peer's structures when it is locked processing that
1147 * message. We hold a reference to the peer hook so we are guaranteed that
1148 * the peer hook and node are still going to exist until
1149 * we are finished there as the hook holds a ref on the node.
1150 * We run this same code again on the peer hook, but that time it is already
1151 * attached to the 'dead' hook.
1152 *
1153 * This routine is called at all stages of hook creation
1154 * on error detection and must be able to handle any such stage.
1155 */
1156 void
1157 ng_destroy_hook(hook_p hook)
1158 {
1159 hook_p peer;
1160 node_p node;
1161
1162 if (hook == &ng_deadhook) { /* better safe than sorry */
1163 printf("ng_destroy_hook called on deadhook\n");
1164 return;
1165 }
1166
1167 /*
1168 * Protect divorce process with mutex, to avoid races on
1169 * simultaneous disconnect.
1170 */
1171 TOPOLOGY_WLOCK();
1172
1173 hook->hk_flags |= HK_INVALID;
1174
1175 peer = NG_HOOK_PEER(hook);
1176 node = NG_HOOK_NODE(hook);
1177
1178 if (peer && (peer != &ng_deadhook)) {
1179 /*
1180 * Set the peer to point to ng_deadhook
1181 * from this moment on we are effectively independent it.
1182 * send it an rmhook message of it's own.
1183 */
1184 peer->hk_peer = &ng_deadhook; /* They no longer know us */
1185 hook->hk_peer = &ng_deadhook; /* Nor us, them */
1186 if (NG_HOOK_NODE(peer) == &ng_deadnode) {
1187 /*
1188 * If it's already divorced from a node,
1189 * just free it.
1190 */
1191 TOPOLOGY_WUNLOCK();
1192 } else {
1193 TOPOLOGY_WUNLOCK();
1194 ng_rmhook_self(peer); /* Send it a surprise */
1195 }
1196 NG_HOOK_UNREF(peer); /* account for peer link */
1197 NG_HOOK_UNREF(hook); /* account for peer link */
1198 } else
1199 TOPOLOGY_WUNLOCK();
1200
1201 TOPOLOGY_NOTOWNED();
1202
1203 /*
1204 * Remove the hook from the node's list to avoid possible recursion
1205 * in case the disconnection results in node shutdown.
1206 */
1207 if (node == &ng_deadnode) { /* happens if called from ng_con_nodes() */
1208 return;
1209 }
1210 LIST_REMOVE(hook, hk_hooks);
1211 node->nd_numhooks--;
1212 if (node->nd_type->disconnect) {
1213 /*
1214 * The type handler may elect to destroy the node so don't
1215 * trust its existence after this point. (except
1216 * that we still hold a reference on it. (which we
1217 * inherrited from the hook we are destroying)
1218 */
1219 (*node->nd_type->disconnect) (hook);
1220 }
1221
1222 /*
1223 * Note that because we will point to ng_deadnode, the original node
1224 * is not decremented automatically so we do that manually.
1225 */
1226 _NG_HOOK_NODE(hook) = &ng_deadnode;
1227 NG_NODE_UNREF(node); /* We no longer point to it so adjust count */
1228 NG_HOOK_UNREF(hook); /* Account for linkage (in list) to node */
1229 }
1230
1231 /*
1232 * Take two hooks on a node and merge the connection so that the given node
1233 * is effectively bypassed.
1234 */
1235 int
1236 ng_bypass(hook_p hook1, hook_p hook2)
1237 {
1238 if (hook1->hk_node != hook2->hk_node) {
1239 TRAP_ERROR();
1240 return (EINVAL);
1241 }
1242 TOPOLOGY_WLOCK();
1243 if (NG_HOOK_NOT_VALID(hook1) || NG_HOOK_NOT_VALID(hook2)) {
1244 TOPOLOGY_WUNLOCK();
1245 return (EINVAL);
1246 }
1247 hook1->hk_peer->hk_peer = hook2->hk_peer;
1248 hook2->hk_peer->hk_peer = hook1->hk_peer;
1249
1250 hook1->hk_peer = &ng_deadhook;
1251 hook2->hk_peer = &ng_deadhook;
1252 TOPOLOGY_WUNLOCK();
1253
1254 NG_HOOK_UNREF(hook1);
1255 NG_HOOK_UNREF(hook2);
1256
1257 /* XXX If we ever cache methods on hooks update them as well */
1258 ng_destroy_hook(hook1);
1259 ng_destroy_hook(hook2);
1260 return (0);
1261 }
1262
1263 /*
1264 * Install a new netgraph type
1265 */
1266 int
1267 ng_newtype(struct ng_type *tp)
1268 {
1269 const size_t namelen = strlen(tp->name);
1270
1271 /* Check version and type name fields */
1272 if ((tp->version != NG_ABI_VERSION) || (namelen == 0) ||
1273 (namelen >= NG_TYPESIZ)) {
1274 TRAP_ERROR();
1275 if (tp->version != NG_ABI_VERSION) {
1276 printf("Netgraph: Node type rejected. ABI mismatch. "
1277 "Suggest recompile\n");
1278 }
1279 return (EINVAL);
1280 }
1281
1282 /* Check for name collision */
1283 if (ng_findtype(tp->name) != NULL) {
1284 TRAP_ERROR();
1285 return (EEXIST);
1286 }
1287
1288 /* Link in new type */
1289 TYPELIST_WLOCK();
1290 LIST_INSERT_HEAD(&ng_typelist, tp, types);
1291 tp->refs = 1; /* first ref is linked list */
1292 TYPELIST_WUNLOCK();
1293 return (0);
1294 }
1295
1296 /*
1297 * unlink a netgraph type
1298 * If no examples exist
1299 */
1300 int
1301 ng_rmtype(struct ng_type *tp)
1302 {
1303 /* Check for name collision */
1304 if (tp->refs != 1) {
1305 TRAP_ERROR();
1306 return (EBUSY);
1307 }
1308
1309 /* Unlink type */
1310 TYPELIST_WLOCK();
1311 LIST_REMOVE(tp, types);
1312 TYPELIST_WUNLOCK();
1313 return (0);
1314 }
1315
1316 /*
1317 * Look for a type of the name given
1318 */
1319 struct ng_type *
1320 ng_findtype(const char *typename)
1321 {
1322 struct ng_type *type;
1323
1324 TYPELIST_RLOCK();
1325 LIST_FOREACH(type, &ng_typelist, types) {
1326 if (strcmp(type->name, typename) == 0)
1327 break;
1328 }
1329 TYPELIST_RUNLOCK();
1330 return (type);
1331 }
1332
1333 /************************************************************************
1334 Composite routines
1335 ************************************************************************/
1336 /*
1337 * Connect two nodes using the specified hooks, using queued functions.
1338 */
1339 static int
1340 ng_con_part3(node_p node, item_p item, hook_p hook)
1341 {
1342 int error = 0;
1343
1344 /*
1345 * When we run, we know that the node 'node' is locked for us.
1346 * Our caller has a reference on the hook.
1347 * Our caller has a reference on the node.
1348 * (In this case our caller is ng_apply_item() ).
1349 * The peer hook has a reference on the hook.
1350 * We are all set up except for the final call to the node, and
1351 * the clearing of the INVALID flag.
1352 */
1353 if (NG_HOOK_NODE(hook) == &ng_deadnode) {
1354 /*
1355 * The node must have been freed again since we last visited
1356 * here. ng_destry_hook() has this effect but nothing else does.
1357 * We should just release our references and
1358 * free anything we can think of.
1359 * Since we know it's been destroyed, and it's our caller
1360 * that holds the references, just return.
1361 */
1362 ERROUT(ENOENT);
1363 }
1364 if (hook->hk_node->nd_type->connect) {
1365 if ((error = (*hook->hk_node->nd_type->connect) (hook))) {
1366 ng_destroy_hook(hook); /* also zaps peer */
1367 printf("failed in ng_con_part3()\n");
1368 ERROUT(error);
1369 }
1370 }
1371 /*
1372 * XXX this is wrong for SMP. Possibly we need
1373 * to separate out 'create' and 'invalid' flags.
1374 * should only set flags on hooks we have locked under our node.
1375 */
1376 hook->hk_flags &= ~HK_INVALID;
1377 done:
1378 NG_FREE_ITEM(item);
1379 return (error);
1380 }
1381
1382 static int
1383 ng_con_part2(node_p node, item_p item, hook_p hook)
1384 {
1385 hook_p peer;
1386 int error = 0;
1387
1388 /*
1389 * When we run, we know that the node 'node' is locked for us.
1390 * Our caller has a reference on the hook.
1391 * Our caller has a reference on the node.
1392 * (In this case our caller is ng_apply_item() ).
1393 * The peer hook has a reference on the hook.
1394 * our node pointer points to the 'dead' node.
1395 * First check the hook name is unique.
1396 * Should not happen because we checked before queueing this.
1397 */
1398 if (ng_findhook(node, NG_HOOK_NAME(hook)) != NULL) {
1399 TRAP_ERROR();
1400 ng_destroy_hook(hook); /* should destroy peer too */
1401 printf("failed in ng_con_part2()\n");
1402 ERROUT(EEXIST);
1403 }
1404 /*
1405 * Check if the node type code has something to say about it
1406 * If it fails, the unref of the hook will also unref the attached node,
1407 * however since that node is 'ng_deadnode' this will do nothing.
1408 * The peer hook will also be destroyed.
1409 */
1410 if (node->nd_type->newhook != NULL) {
1411 if ((error = (*node->nd_type->newhook)(node, hook,
1412 hook->hk_name))) {
1413 ng_destroy_hook(hook); /* should destroy peer too */
1414 printf("failed in ng_con_part2()\n");
1415 ERROUT(error);
1416 }
1417 }
1418
1419 /*
1420 * The 'type' agrees so far, so go ahead and link it in.
1421 * We'll ask again later when we actually connect the hooks.
1422 */
1423 hook->hk_node = node; /* just overwrite ng_deadnode */
1424 NG_NODE_REF(node); /* each hook counts as a reference */
1425 LIST_INSERT_HEAD(&node->nd_hooks, hook, hk_hooks);
1426 node->nd_numhooks++;
1427 NG_HOOK_REF(hook); /* one for the node */
1428
1429 /*
1430 * We now have a symmetrical situation, where both hooks have been
1431 * linked to their nodes, the newhook methods have been called
1432 * And the references are all correct. The hooks are still marked
1433 * as invalid, as we have not called the 'connect' methods
1434 * yet.
1435 * We can call the local one immediately as we have the
1436 * node locked, but we need to queue the remote one.
1437 */
1438 if (hook->hk_node->nd_type->connect) {
1439 if ((error = (*hook->hk_node->nd_type->connect) (hook))) {
1440 ng_destroy_hook(hook); /* also zaps peer */
1441 printf("failed in ng_con_part2(A)\n");
1442 ERROUT(error);
1443 }
1444 }
1445
1446 /*
1447 * Acquire topo mutex to avoid race with ng_destroy_hook().
1448 */
1449 TOPOLOGY_RLOCK();
1450 peer = hook->hk_peer;
1451 if (peer == &ng_deadhook) {
1452 TOPOLOGY_RUNLOCK();
1453 printf("failed in ng_con_part2(B)\n");
1454 ng_destroy_hook(hook);
1455 ERROUT(ENOENT);
1456 }
1457 TOPOLOGY_RUNLOCK();
1458
1459 if ((error = ng_send_fn2(peer->hk_node, peer, item, &ng_con_part3,
1460 NULL, 0, NG_REUSE_ITEM))) {
1461 printf("failed in ng_con_part2(C)\n");
1462 ng_destroy_hook(hook); /* also zaps peer */
1463 return (error); /* item was consumed. */
1464 }
1465 hook->hk_flags &= ~HK_INVALID; /* need both to be able to work */
1466 return (0); /* item was consumed. */
1467 done:
1468 NG_FREE_ITEM(item);
1469 return (error);
1470 }
1471
1472 /*
1473 * Connect this node with another node. We assume that this node is
1474 * currently locked, as we are only called from an NGM_CONNECT message.
1475 */
1476 static int
1477 ng_con_nodes(item_p item, node_p node, const char *name,
1478 node_p node2, const char *name2)
1479 {
1480 int error;
1481 hook_p hook;
1482 hook_p hook2;
1483
1484 if (ng_findhook(node2, name2) != NULL) {
1485 return(EEXIST);
1486 }
1487 if ((error = ng_add_hook(node, name, &hook))) /* gives us a ref */
1488 return (error);
1489 /* Allocate the other hook and link it up */
1490 NG_ALLOC_HOOK(hook2);
1491 if (hook2 == NULL) {
1492 TRAP_ERROR();
1493 ng_destroy_hook(hook); /* XXX check ref counts so far */
1494 NG_HOOK_UNREF(hook); /* including our ref */
1495 return (ENOMEM);
1496 }
1497 hook2->hk_refs = 1; /* start with a reference for us. */
1498 hook2->hk_flags = HK_INVALID;
1499 hook2->hk_peer = hook; /* Link the two together */
1500 hook->hk_peer = hook2;
1501 NG_HOOK_REF(hook); /* Add a ref for the peer to each*/
1502 NG_HOOK_REF(hook2);
1503 hook2->hk_node = &ng_deadnode;
1504 strlcpy(NG_HOOK_NAME(hook2), name2, NG_HOOKSIZ);
1505
1506 /*
1507 * Queue the function above.
1508 * Procesing continues in that function in the lock context of
1509 * the other node.
1510 */
1511 if ((error = ng_send_fn2(node2, hook2, item, &ng_con_part2, NULL, 0,
1512 NG_NOFLAGS))) {
1513 printf("failed in ng_con_nodes(): %d\n", error);
1514 ng_destroy_hook(hook); /* also zaps peer */
1515 }
1516
1517 NG_HOOK_UNREF(hook); /* Let each hook go if it wants to */
1518 NG_HOOK_UNREF(hook2);
1519 return (error);
1520 }
1521
1522 /*
1523 * Make a peer and connect.
1524 * We assume that the local node is locked.
1525 * The new node probably doesn't need a lock until
1526 * it has a hook, because it cannot really have any work until then,
1527 * but we should think about it a bit more.
1528 *
1529 * The problem may come if the other node also fires up
1530 * some hardware or a timer or some other source of activation,
1531 * also it may already get a command msg via it's ID.
1532 *
1533 * We could use the same method as ng_con_nodes() but we'd have
1534 * to add ability to remove the node when failing. (Not hard, just
1535 * make arg1 point to the node to remove).
1536 * Unless of course we just ignore failure to connect and leave
1537 * an unconnected node?
1538 */
1539 static int
1540 ng_mkpeer(node_p node, const char *name, const char *name2, char *type)
1541 {
1542 node_p node2;
1543 hook_p hook1, hook2;
1544 int error;
1545
1546 if ((error = ng_make_node(type, &node2))) {
1547 return (error);
1548 }
1549
1550 if ((error = ng_add_hook(node, name, &hook1))) { /* gives us a ref */
1551 ng_rmnode(node2, NULL, NULL, 0);
1552 return (error);
1553 }
1554
1555 if ((error = ng_add_hook(node2, name2, &hook2))) {
1556 ng_rmnode(node2, NULL, NULL, 0);
1557 ng_destroy_hook(hook1);
1558 NG_HOOK_UNREF(hook1);
1559 return (error);
1560 }
1561
1562 /*
1563 * Actually link the two hooks together.
1564 */
1565 hook1->hk_peer = hook2;
1566 hook2->hk_peer = hook1;
1567
1568 /* Each hook is referenced by the other */
1569 NG_HOOK_REF(hook1);
1570 NG_HOOK_REF(hook2);
1571
1572 /* Give each node the opportunity to veto the pending connection */
1573 if (hook1->hk_node->nd_type->connect) {
1574 error = (*hook1->hk_node->nd_type->connect) (hook1);
1575 }
1576
1577 if ((error == 0) && hook2->hk_node->nd_type->connect) {
1578 error = (*hook2->hk_node->nd_type->connect) (hook2);
1579
1580 }
1581
1582 /*
1583 * drop the references we were holding on the two hooks.
1584 */
1585 if (error) {
1586 ng_destroy_hook(hook2); /* also zaps hook1 */
1587 ng_rmnode(node2, NULL, NULL, 0);
1588 } else {
1589 /* As a last act, allow the hooks to be used */
1590 hook1->hk_flags &= ~HK_INVALID;
1591 hook2->hk_flags &= ~HK_INVALID;
1592 }
1593 NG_HOOK_UNREF(hook1);
1594 NG_HOOK_UNREF(hook2);
1595 return (error);
1596 }
1597
1598 /************************************************************************
1599 Utility routines to send self messages
1600 ************************************************************************/
1601
1602 /* Shut this node down as soon as everyone is clear of it */
1603 /* Should add arg "immediately" to jump the queue */
1604 int
1605 ng_rmnode_self(node_p node)
1606 {
1607 int error;
1608
1609 if (node == &ng_deadnode)
1610 return (0);
1611 node->nd_flags |= NGF_INVALID;
1612 if (node->nd_flags & NGF_CLOSING)
1613 return (0);
1614
1615 error = ng_send_fn(node, NULL, &ng_rmnode, NULL, 0);
1616 return (error);
1617 }
1618
1619 static void
1620 ng_rmhook_part2(node_p node, hook_p hook, void *arg1, int arg2)
1621 {
1622 ng_destroy_hook(hook);
1623 return ;
1624 }
1625
1626 int
1627 ng_rmhook_self(hook_p hook)
1628 {
1629 int error;
1630 node_p node = NG_HOOK_NODE(hook);
1631
1632 if (node == &ng_deadnode)
1633 return (0);
1634
1635 error = ng_send_fn(node, hook, &ng_rmhook_part2, NULL, 0);
1636 return (error);
1637 }
1638
1639 /***********************************************************************
1640 * Parse and verify a string of the form: <NODE:><PATH>
1641 *
1642 * Such a string can refer to a specific node or a specific hook
1643 * on a specific node, depending on how you look at it. In the
1644 * latter case, the PATH component must not end in a dot.
1645 *
1646 * Both <NODE:> and <PATH> are optional. The <PATH> is a string
1647 * of hook names separated by dots. This breaks out the original
1648 * string, setting *nodep to "NODE" (or NULL if none) and *pathp
1649 * to "PATH" (or NULL if degenerate). Also, *hookp will point to
1650 * the final hook component of <PATH>, if any, otherwise NULL.
1651 *
1652 * This returns -1 if the path is malformed. The char ** are optional.
1653 ***********************************************************************/
1654 int
1655 ng_path_parse(char *addr, char **nodep, char **pathp, char **hookp)
1656 {
1657 char *node, *path, *hook;
1658 int k;
1659
1660 /*
1661 * Extract absolute NODE, if any
1662 */
1663 for (path = addr; *path && *path != ':'; path++);
1664 if (*path) {
1665 node = addr; /* Here's the NODE */
1666 *path++ = '\0'; /* Here's the PATH */
1667
1668 /* Node name must not be empty */
1669 if (!*node)
1670 return -1;
1671
1672 /* A name of "." is OK; otherwise '.' not allowed */
1673 if (strcmp(node, ".") != 0) {
1674 for (k = 0; node[k]; k++)
1675 if (node[k] == '.')
1676 return -1;
1677 }
1678 } else {
1679 node = NULL; /* No absolute NODE */
1680 path = addr; /* Here's the PATH */
1681 }
1682
1683 /* Snoop for illegal characters in PATH */
1684 for (k = 0; path[k]; k++)
1685 if (path[k] == ':')
1686 return -1;
1687
1688 /* Check for no repeated dots in PATH */
1689 for (k = 0; path[k]; k++)
1690 if (path[k] == '.' && path[k + 1] == '.')
1691 return -1;
1692
1693 /* Remove extra (degenerate) dots from beginning or end of PATH */
1694 if (path[0] == '.')
1695 path++;
1696 if (*path && path[strlen(path) - 1] == '.')
1697 path[strlen(path) - 1] = 0;
1698
1699 /* If PATH has a dot, then we're not talking about a hook */
1700 if (*path) {
1701 for (hook = path, k = 0; path[k]; k++)
1702 if (path[k] == '.') {
1703 hook = NULL;
1704 break;
1705 }
1706 } else
1707 path = hook = NULL;
1708
1709 /* Done */
1710 if (nodep)
1711 *nodep = node;
1712 if (pathp)
1713 *pathp = path;
1714 if (hookp)
1715 *hookp = hook;
1716 return (0);
1717 }
1718
1719 /*
1720 * Given a path, which may be absolute or relative, and a starting node,
1721 * return the destination node.
1722 */
1723 int
1724 ng_path2noderef(node_p here, const char *address, node_p *destp,
1725 hook_p *lasthook)
1726 {
1727 char fullpath[NG_PATHSIZ];
1728 char *nodename, *path;
1729 node_p node, oldnode;
1730
1731 /* Initialize */
1732 if (destp == NULL) {
1733 TRAP_ERROR();
1734 return EINVAL;
1735 }
1736 *destp = NULL;
1737
1738 /* Make a writable copy of address for ng_path_parse() */
1739 strncpy(fullpath, address, sizeof(fullpath) - 1);
1740 fullpath[sizeof(fullpath) - 1] = '\0';
1741
1742 /* Parse out node and sequence of hooks */
1743 if (ng_path_parse(fullpath, &nodename, &path, NULL) < 0) {
1744 TRAP_ERROR();
1745 return EINVAL;
1746 }
1747
1748 /*
1749 * For an absolute address, jump to the starting node.
1750 * Note that this holds a reference on the node for us.
1751 * Don't forget to drop the reference if we don't need it.
1752 */
1753 if (nodename) {
1754 node = ng_name2noderef(here, nodename);
1755 if (node == NULL) {
1756 TRAP_ERROR();
1757 return (ENOENT);
1758 }
1759 } else {
1760 if (here == NULL) {
1761 TRAP_ERROR();
1762 return (EINVAL);
1763 }
1764 node = here;
1765 NG_NODE_REF(node);
1766 }
1767
1768 if (path == NULL) {
1769 if (lasthook != NULL)
1770 *lasthook = NULL;
1771 *destp = node;
1772 return (0);
1773 }
1774
1775 /*
1776 * Now follow the sequence of hooks
1777 *
1778 * XXXGL: The path may demolish as we go the sequence, but if
1779 * we hold the topology mutex at critical places, then, I hope,
1780 * we would always have valid pointers in hand, although the
1781 * path behind us may no longer exist.
1782 */
1783 for (;;) {
1784 hook_p hook;
1785 char *segment;
1786
1787 /*
1788 * Break out the next path segment. Replace the dot we just
1789 * found with a NUL; "path" points to the next segment (or the
1790 * NUL at the end).
1791 */
1792 for (segment = path; *path != '\0'; path++) {
1793 if (*path == '.') {
1794 *path++ = '\0';
1795 break;
1796 }
1797 }
1798
1799 /* We have a segment, so look for a hook by that name */
1800 hook = ng_findhook(node, segment);
1801
1802 TOPOLOGY_WLOCK();
1803 /* Can't get there from here... */
1804 if (hook == NULL || NG_HOOK_PEER(hook) == NULL ||
1805 NG_HOOK_NOT_VALID(hook) ||
1806 NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook))) {
1807 TRAP_ERROR();
1808 NG_NODE_UNREF(node);
1809 TOPOLOGY_WUNLOCK();
1810 return (ENOENT);
1811 }
1812
1813 /*
1814 * Hop on over to the next node
1815 * XXX
1816 * Big race conditions here as hooks and nodes go away
1817 * *** Idea.. store an ng_ID_t in each hook and use that
1818 * instead of the direct hook in this crawl?
1819 */
1820 oldnode = node;
1821 if ((node = NG_PEER_NODE(hook)))
1822 NG_NODE_REF(node); /* XXX RACE */
1823 NG_NODE_UNREF(oldnode); /* XXX another race */
1824 if (NG_NODE_NOT_VALID(node)) {
1825 NG_NODE_UNREF(node); /* XXX more races */
1826 TOPOLOGY_WUNLOCK();
1827 TRAP_ERROR();
1828 return (ENXIO);
1829 }
1830
1831 if (*path == '\0') {
1832 if (lasthook != NULL) {
1833 if (hook != NULL) {
1834 *lasthook = NG_HOOK_PEER(hook);
1835 NG_HOOK_REF(*lasthook);
1836 } else
1837 *lasthook = NULL;
1838 }
1839 TOPOLOGY_WUNLOCK();
1840 *destp = node;
1841 return (0);
1842 }
1843 TOPOLOGY_WUNLOCK();
1844 }
1845 }
1846
1847 /***************************************************************\
1848 * Input queue handling.
1849 * All activities are submitted to the node via the input queue
1850 * which implements a multiple-reader/single-writer gate.
1851 * Items which cannot be handled immediately are queued.
1852 *
1853 * read-write queue locking inline functions *
1854 \***************************************************************/
1855
1856 static __inline void ng_queue_rw(node_p node, item_p item, int rw);
1857 static __inline item_p ng_dequeue(node_p node, int *rw);
1858 static __inline item_p ng_acquire_read(node_p node, item_p item);
1859 static __inline item_p ng_acquire_write(node_p node, item_p item);
1860 static __inline void ng_leave_read(node_p node);
1861 static __inline void ng_leave_write(node_p node);
1862
1863 /*
1864 * Definition of the bits fields in the ng_queue flag word.
1865 * Defined here rather than in netgraph.h because no-one should fiddle
1866 * with them.
1867 *
1868 * The ordering here may be important! don't shuffle these.
1869 */
1870 /*-
1871 Safety Barrier--------+ (adjustable to suit taste) (not used yet)
1872 |
1873 V
1874 +-------+-------+-------+-------+-------+-------+-------+-------+
1875 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
1876 | |A|c|t|i|v|e| |R|e|a|d|e|r| |C|o|u|n|t| | | | | | | | | |P|A|
1877 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |O|W|
1878 +-------+-------+-------+-------+-------+-------+-------+-------+
1879 \___________________________ ____________________________/ | |
1880 V | |
1881 [active reader count] | |
1882 | |
1883 Operation Pending -------------------------------+ |
1884 |
1885 Active Writer ---------------------------------------+
1886
1887 Node queue has such semantics:
1888 - All flags modifications are atomic.
1889 - Reader count can be incremented only if there is no writer or pending flags.
1890 As soon as this can't be done with single operation, it is implemented with
1891 spin loop and atomic_cmpset().
1892 - Writer flag can be set only if there is no any bits set.
1893 It is implemented with atomic_cmpset().
1894 - Pending flag can be set any time, but to avoid collision on queue processing
1895 all queue fields are protected by the mutex.
1896 - Queue processing thread reads queue holding the mutex, but releases it while
1897 processing. When queue is empty pending flag is removed.
1898 */
1899
1900 #define WRITER_ACTIVE 0x00000001
1901 #define OP_PENDING 0x00000002
1902 #define READER_INCREMENT 0x00000004
1903 #define READER_MASK 0xfffffffc /* Not valid if WRITER_ACTIVE is set */
1904 #define SAFETY_BARRIER 0x00100000 /* 128K items queued should be enough */
1905
1906 /* Defines of more elaborate states on the queue */
1907 /* Mask of bits a new read cares about */
1908 #define NGQ_RMASK (WRITER_ACTIVE|OP_PENDING)
1909
1910 /* Mask of bits a new write cares about */
1911 #define NGQ_WMASK (NGQ_RMASK|READER_MASK)
1912
1913 /* Test to decide if there is something on the queue. */
1914 #define QUEUE_ACTIVE(QP) ((QP)->q_flags & OP_PENDING)
1915
1916 /* How to decide what the next queued item is. */
1917 #define HEAD_IS_READER(QP) NGI_QUEUED_READER(STAILQ_FIRST(&(QP)->queue))
1918 #define HEAD_IS_WRITER(QP) NGI_QUEUED_WRITER(STAILQ_FIRST(&(QP)->queue)) /* notused */
1919
1920 /* Read the status to decide if the next item on the queue can now run. */
1921 #define QUEUED_READER_CAN_PROCEED(QP) \
1922 (((QP)->q_flags & (NGQ_RMASK & ~OP_PENDING)) == 0)
1923 #define QUEUED_WRITER_CAN_PROCEED(QP) \
1924 (((QP)->q_flags & (NGQ_WMASK & ~OP_PENDING)) == 0)
1925
1926 /* Is there a chance of getting ANY work off the queue? */
1927 #define NEXT_QUEUED_ITEM_CAN_PROCEED(QP) \
1928 ((HEAD_IS_READER(QP)) ? QUEUED_READER_CAN_PROCEED(QP) : \
1929 QUEUED_WRITER_CAN_PROCEED(QP))
1930
1931 #define NGQRW_R 0
1932 #define NGQRW_W 1
1933
1934 #define NGQ2_WORKQ 0x00000001
1935
1936 /*
1937 * Taking into account the current state of the queue and node, possibly take
1938 * the next entry off the queue and return it. Return NULL if there was
1939 * nothing we could return, either because there really was nothing there, or
1940 * because the node was in a state where it cannot yet process the next item
1941 * on the queue.
1942 */
1943 static __inline item_p
1944 ng_dequeue(node_p node, int *rw)
1945 {
1946 item_p item;
1947 struct ng_queue *ngq = &node->nd_input_queue;
1948
1949 /* This MUST be called with the mutex held. */
1950 mtx_assert(&ngq->q_mtx, MA_OWNED);
1951
1952 /* If there is nothing queued, then just return. */
1953 if (!QUEUE_ACTIVE(ngq)) {
1954 CTR4(KTR_NET, "%20s: node [%x] (%p) queue empty; "
1955 "queue flags 0x%lx", __func__,
1956 node->nd_ID, node, ngq->q_flags);
1957 return (NULL);
1958 }
1959
1960 /*
1961 * From here, we can assume there is a head item.
1962 * We need to find out what it is and if it can be dequeued, given
1963 * the current state of the node.
1964 */
1965 if (HEAD_IS_READER(ngq)) {
1966 while (1) {
1967 long t = ngq->q_flags;
1968 if (t & WRITER_ACTIVE) {
1969 /* There is writer, reader can't proceed. */
1970 CTR4(KTR_NET, "%20s: node [%x] (%p) queued "
1971 "reader can't proceed; queue flags 0x%lx",
1972 __func__, node->nd_ID, node, t);
1973 return (NULL);
1974 }
1975 if (atomic_cmpset_acq_int(&ngq->q_flags, t,
1976 t + READER_INCREMENT))
1977 break;
1978 cpu_spinwait();
1979 }
1980 /* We have got reader lock for the node. */
1981 *rw = NGQRW_R;
1982 } else if (atomic_cmpset_acq_int(&ngq->q_flags, OP_PENDING,
1983 OP_PENDING + WRITER_ACTIVE)) {
1984 /* We have got writer lock for the node. */
1985 *rw = NGQRW_W;
1986 } else {
1987 /* There is somebody other, writer can't proceed. */
1988 CTR4(KTR_NET, "%20s: node [%x] (%p) queued writer can't "
1989 "proceed; queue flags 0x%lx", __func__, node->nd_ID, node,
1990 ngq->q_flags);
1991 return (NULL);
1992 }
1993
1994 /*
1995 * Now we dequeue the request (whatever it may be) and correct the
1996 * pending flags and the next and last pointers.
1997 */
1998 item = STAILQ_FIRST(&ngq->queue);
1999 STAILQ_REMOVE_HEAD(&ngq->queue, el_next);
2000 if (STAILQ_EMPTY(&ngq->queue))
2001 atomic_clear_int(&ngq->q_flags, OP_PENDING);
2002 CTR6(KTR_NET, "%20s: node [%x] (%p) returning item %p as %s; queue "
2003 "flags 0x%lx", __func__, node->nd_ID, node, item, *rw ? "WRITER" :
2004 "READER", ngq->q_flags);
2005 return (item);
2006 }
2007
2008 /*
2009 * Queue a packet to be picked up later by someone else.
2010 * If the queue could be run now, add node to the queue handler's worklist.
2011 */
2012 static __inline void
2013 ng_queue_rw(node_p node, item_p item, int rw)
2014 {
2015 struct ng_queue *ngq = &node->nd_input_queue;
2016 if (rw == NGQRW_W)
2017 NGI_SET_WRITER(item);
2018 else
2019 NGI_SET_READER(item);
2020 item->depth = 1;
2021
2022 NG_QUEUE_LOCK(ngq);
2023 /* Set OP_PENDING flag and enqueue the item. */
2024 atomic_set_int(&ngq->q_flags, OP_PENDING);
2025 STAILQ_INSERT_TAIL(&ngq->queue, item, el_next);
2026
2027 CTR5(KTR_NET, "%20s: node [%x] (%p) queued item %p as %s", __func__,
2028 node->nd_ID, node, item, rw ? "WRITER" : "READER" );
2029
2030 /*
2031 * We can take the worklist lock with the node locked
2032 * BUT NOT THE REVERSE!
2033 */
2034 if (NEXT_QUEUED_ITEM_CAN_PROCEED(ngq))
2035 ng_worklist_add(node);
2036 NG_QUEUE_UNLOCK(ngq);
2037 }
2038
2039 /* Acquire reader lock on node. If node is busy, queue the packet. */
2040 static __inline item_p
2041 ng_acquire_read(node_p node, item_p item)
2042 {
2043 KASSERT(node != &ng_deadnode,
2044 ("%s: working on deadnode", __func__));
2045
2046 /* Reader needs node without writer and pending items. */
2047 for (;;) {
2048 long t = node->nd_input_queue.q_flags;
2049 if (t & NGQ_RMASK)
2050 break; /* Node is not ready for reader. */
2051 if (atomic_cmpset_acq_int(&node->nd_input_queue.q_flags, t,
2052 t + READER_INCREMENT)) {
2053 /* Successfully grabbed node */
2054 CTR4(KTR_NET, "%20s: node [%x] (%p) acquired item %p",
2055 __func__, node->nd_ID, node, item);
2056 return (item);
2057 }
2058 cpu_spinwait();
2059 }
2060
2061 /* Queue the request for later. */
2062 ng_queue_rw(node, item, NGQRW_R);
2063
2064 return (NULL);
2065 }
2066
2067 /* Acquire writer lock on node. If node is busy, queue the packet. */
2068 static __inline item_p
2069 ng_acquire_write(node_p node, item_p item)
2070 {
2071 KASSERT(node != &ng_deadnode,
2072 ("%s: working on deadnode", __func__));
2073
2074 /* Writer needs completely idle node. */
2075 if (atomic_cmpset_acq_int(&node->nd_input_queue.q_flags, 0,
2076 WRITER_ACTIVE)) {
2077 /* Successfully grabbed node */
2078 CTR4(KTR_NET, "%20s: node [%x] (%p) acquired item %p",
2079 __func__, node->nd_ID, node, item);
2080 return (item);
2081 }
2082
2083 /* Queue the request for later. */
2084 ng_queue_rw(node, item, NGQRW_W);
2085
2086 return (NULL);
2087 }
2088
2089 #if 0
2090 static __inline item_p
2091 ng_upgrade_write(node_p node, item_p item)
2092 {
2093 struct ng_queue *ngq = &node->nd_input_queue;
2094 KASSERT(node != &ng_deadnode,
2095 ("%s: working on deadnode", __func__));
2096
2097 NGI_SET_WRITER(item);
2098
2099 NG_QUEUE_LOCK(ngq);
2100
2101 /*
2102 * There will never be no readers as we are there ourselves.
2103 * Set the WRITER_ACTIVE flags ASAP to block out fast track readers.
2104 * The caller we are running from will call ng_leave_read()
2105 * soon, so we must account for that. We must leave again with the
2106 * READER lock. If we find other readers, then
2107 * queue the request for later. However "later" may be rignt now
2108 * if there are no readers. We don't really care if there are queued
2109 * items as we will bypass them anyhow.
2110 */
2111 atomic_add_int(&ngq->q_flags, WRITER_ACTIVE - READER_INCREMENT);
2112 if ((ngq->q_flags & (NGQ_WMASK & ~OP_PENDING)) == WRITER_ACTIVE) {
2113 NG_QUEUE_UNLOCK(ngq);
2114
2115 /* It's just us, act on the item. */
2116 /* will NOT drop writer lock when done */
2117 ng_apply_item(node, item, 0);
2118
2119 /*
2120 * Having acted on the item, atomically
2121 * downgrade back to READER and finish up.
2122 */
2123 atomic_add_int(&ngq->q_flags, READER_INCREMENT - WRITER_ACTIVE);
2124
2125 /* Our caller will call ng_leave_read() */
2126 return;
2127 }
2128 /*
2129 * It's not just us active, so queue us AT THE HEAD.
2130 * "Why?" I hear you ask.
2131 * Put us at the head of the queue as we've already been
2132 * through it once. If there is nothing else waiting,
2133 * set the correct flags.
2134 */
2135 if (STAILQ_EMPTY(&ngq->queue)) {
2136 /* We've gone from, 0 to 1 item in the queue */
2137 atomic_set_int(&ngq->q_flags, OP_PENDING);
2138
2139 CTR3(KTR_NET, "%20s: node [%x] (%p) set OP_PENDING", __func__,
2140 node->nd_ID, node);
2141 };
2142 STAILQ_INSERT_HEAD(&ngq->queue, item, el_next);
2143 CTR4(KTR_NET, "%20s: node [%x] (%p) requeued item %p as WRITER",
2144 __func__, node->nd_ID, node, item );
2145
2146 /* Reverse what we did above. That downgrades us back to reader */
2147 atomic_add_int(&ngq->q_flags, READER_INCREMENT - WRITER_ACTIVE);
2148 if (QUEUE_ACTIVE(ngq) && NEXT_QUEUED_ITEM_CAN_PROCEED(ngq))
2149 ng_worklist_add(node);
2150 NG_QUEUE_UNLOCK(ngq);
2151
2152 return;
2153 }
2154 #endif
2155
2156 /* Release reader lock. */
2157 static __inline void
2158 ng_leave_read(node_p node)
2159 {
2160 atomic_subtract_rel_int(&node->nd_input_queue.q_flags, READER_INCREMENT);
2161 }
2162
2163 /* Release writer lock. */
2164 static __inline void
2165 ng_leave_write(node_p node)
2166 {
2167 atomic_clear_rel_int(&node->nd_input_queue.q_flags, WRITER_ACTIVE);
2168 }
2169
2170 /* Purge node queue. Called on node shutdown. */
2171 static void
2172 ng_flush_input_queue(node_p node)
2173 {
2174 struct ng_queue *ngq = &node->nd_input_queue;
2175 item_p item;
2176
2177 NG_QUEUE_LOCK(ngq);
2178 while ((item = STAILQ_FIRST(&ngq->queue)) != NULL) {
2179 STAILQ_REMOVE_HEAD(&ngq->queue, el_next);
2180 if (STAILQ_EMPTY(&ngq->queue))
2181 atomic_clear_int(&ngq->q_flags, OP_PENDING);
2182 NG_QUEUE_UNLOCK(ngq);
2183
2184 /* If the item is supplying a callback, call it with an error */
2185 if (item->apply != NULL) {
2186 if (item->depth == 1)
2187 item->apply->error = ENOENT;
2188 if (refcount_release(&item->apply->refs)) {
2189 (*item->apply->apply)(item->apply->context,
2190 item->apply->error);
2191 }
2192 }
2193 NG_FREE_ITEM(item);
2194 NG_QUEUE_LOCK(ngq);
2195 }
2196 NG_QUEUE_UNLOCK(ngq);
2197 }
2198
2199 /***********************************************************************
2200 * Externally visible method for sending or queueing messages or data.
2201 ***********************************************************************/
2202
2203 /*
2204 * The module code should have filled out the item correctly by this stage:
2205 * Common:
2206 * reference to destination node.
2207 * Reference to destination rcv hook if relevant.
2208 * apply pointer must be or NULL or reference valid struct ng_apply_info.
2209 * Data:
2210 * pointer to mbuf
2211 * Control_Message:
2212 * pointer to msg.
2213 * ID of original sender node. (return address)
2214 * Function:
2215 * Function pointer
2216 * void * argument
2217 * integer argument
2218 *
2219 * The nodes have several routines and macros to help with this task:
2220 */
2221
2222 int
2223 ng_snd_item(item_p item, int flags)
2224 {
2225 hook_p hook;
2226 node_p node;
2227 int queue, rw;
2228 struct ng_queue *ngq;
2229 int error = 0;
2230
2231 /* We are sending item, so it must be present! */
2232 KASSERT(item != NULL, ("ng_snd_item: item is NULL"));
2233
2234 #ifdef NETGRAPH_DEBUG
2235 _ngi_check(item, __FILE__, __LINE__);
2236 #endif
2237
2238 /* Item was sent once more, postpone apply() call. */
2239 if (item->apply)
2240 refcount_acquire(&item->apply->refs);
2241
2242 node = NGI_NODE(item);
2243 /* Node is never optional. */
2244 KASSERT(node != NULL, ("ng_snd_item: node is NULL"));
2245
2246 hook = NGI_HOOK(item);
2247 /* Valid hook and mbuf are mandatory for data. */
2248 if ((item->el_flags & NGQF_TYPE) == NGQF_DATA) {
2249 KASSERT(hook != NULL, ("ng_snd_item: hook for data is NULL"));
2250 if (NGI_M(item) == NULL)
2251 ERROUT(EINVAL);
2252 CHECK_DATA_MBUF(NGI_M(item));
2253 }
2254
2255 /*
2256 * If the item or the node specifies single threading, force
2257 * writer semantics. Similarly, the node may say one hook always
2258 * produces writers. These are overrides.
2259 */
2260 if (((item->el_flags & NGQF_RW) == NGQF_WRITER) ||
2261 (node->nd_flags & NGF_FORCE_WRITER) ||
2262 (hook && (hook->hk_flags & HK_FORCE_WRITER))) {
2263 rw = NGQRW_W;
2264 } else {
2265 rw = NGQRW_R;
2266 }
2267
2268 /*
2269 * If sender or receiver requests queued delivery, or call graph
2270 * loops back from outbound to inbound path, or stack usage
2271 * level is dangerous - enqueue message.
2272 */
2273 if ((flags & NG_QUEUE) || (hook && (hook->hk_flags & HK_QUEUE))) {
2274 queue = 1;
2275 } else if (hook && (hook->hk_flags & HK_TO_INBOUND) &&
2276 curthread->td_ng_outbound) {
2277 queue = 1;
2278 } else {
2279 queue = 0;
2280 #ifdef GET_STACK_USAGE
2281 /*
2282 * Most of netgraph nodes have small stack consumption and
2283 * for them 25% of free stack space is more than enough.
2284 * Nodes/hooks with higher stack usage should be marked as
2285 * HI_STACK. For them 50% of stack will be guaranteed then.
2286 * XXX: Values 25% and 50% are completely empirical.
2287 */
2288 size_t st, su, sl;
2289 GET_STACK_USAGE(st, su);
2290 sl = st - su;
2291 if ((sl * 4 < st) || ((sl * 2 < st) &&
2292 ((node->nd_flags & NGF_HI_STACK) || (hook &&
2293 (hook->hk_flags & HK_HI_STACK)))))
2294 queue = 1;
2295 #endif
2296 }
2297
2298 if (queue) {
2299 /* Put it on the queue for that node*/
2300 ng_queue_rw(node, item, rw);
2301 return ((flags & NG_PROGRESS) ? EINPROGRESS : 0);
2302 }
2303
2304 /*
2305 * We already decided how we will be queueud or treated.
2306 * Try get the appropriate operating permission.
2307 */
2308 if (rw == NGQRW_R)
2309 item = ng_acquire_read(node, item);
2310 else
2311 item = ng_acquire_write(node, item);
2312
2313 /* Item was queued while trying to get permission. */
2314 if (item == NULL)
2315 return ((flags & NG_PROGRESS) ? EINPROGRESS : 0);
2316
2317 NGI_GET_NODE(item, node); /* zaps stored node */
2318
2319 item->depth++;
2320 error = ng_apply_item(node, item, rw); /* drops r/w lock when done */
2321
2322 /* If something is waiting on queue and ready, schedule it. */
2323 ngq = &node->nd_input_queue;
2324 if (QUEUE_ACTIVE(ngq)) {
2325 NG_QUEUE_LOCK(ngq);
2326 if (QUEUE_ACTIVE(ngq) && NEXT_QUEUED_ITEM_CAN_PROCEED(ngq))
2327 ng_worklist_add(node);
2328 NG_QUEUE_UNLOCK(ngq);
2329 }
2330
2331 /*
2332 * Node may go away as soon as we remove the reference.
2333 * Whatever we do, DO NOT access the node again!
2334 */
2335 NG_NODE_UNREF(node);
2336
2337 return (error);
2338
2339 done:
2340 /* If was not sent, apply callback here. */
2341 if (item->apply != NULL) {
2342 if (item->depth == 0 && error != 0)
2343 item->apply->error = error;
2344 if (refcount_release(&item->apply->refs)) {
2345 (*item->apply->apply)(item->apply->context,
2346 item->apply->error);
2347 }
2348 }
2349
2350 NG_FREE_ITEM(item);
2351 return (error);
2352 }
2353
2354 /*
2355 * We have an item that was possibly queued somewhere.
2356 * It should contain all the information needed
2357 * to run it on the appropriate node/hook.
2358 * If there is apply pointer and we own the last reference, call apply().
2359 */
2360 static int
2361 ng_apply_item(node_p node, item_p item, int rw)
2362 {
2363 hook_p hook;
2364 ng_rcvdata_t *rcvdata;
2365 ng_rcvmsg_t *rcvmsg;
2366 struct ng_apply_info *apply;
2367 int error = 0, depth;
2368
2369 /* Node and item are never optional. */
2370 KASSERT(node != NULL, ("ng_apply_item: node is NULL"));
2371 KASSERT(item != NULL, ("ng_apply_item: item is NULL"));
2372
2373 NGI_GET_HOOK(item, hook); /* clears stored hook */
2374 #ifdef NETGRAPH_DEBUG
2375 _ngi_check(item, __FILE__, __LINE__);
2376 #endif
2377
2378 apply = item->apply;
2379 depth = item->depth;
2380
2381 switch (item->el_flags & NGQF_TYPE) {
2382 case NGQF_DATA:
2383 /*
2384 * Check things are still ok as when we were queued.
2385 */
2386 KASSERT(hook != NULL, ("ng_apply_item: hook for data is NULL"));
2387 if (NG_HOOK_NOT_VALID(hook) ||
2388 NG_NODE_NOT_VALID(node)) {
2389 error = EIO;
2390 NG_FREE_ITEM(item);
2391 break;
2392 }
2393 /*
2394 * If no receive method, just silently drop it.
2395 * Give preference to the hook over-ride method.
2396 */
2397 if ((!(rcvdata = hook->hk_rcvdata)) &&
2398 (!(rcvdata = NG_HOOK_NODE(hook)->nd_type->rcvdata))) {
2399 error = 0;
2400 NG_FREE_ITEM(item);
2401 break;
2402 }
2403 error = (*rcvdata)(hook, item);
2404 break;
2405 case NGQF_MESG:
2406 if (hook && NG_HOOK_NOT_VALID(hook)) {
2407 /*
2408 * The hook has been zapped then we can't use it.
2409 * Immediately drop its reference.
2410 * The message may not need it.
2411 */
2412 NG_HOOK_UNREF(hook);
2413 hook = NULL;
2414 }
2415 /*
2416 * Similarly, if the node is a zombie there is
2417 * nothing we can do with it, drop everything.
2418 */
2419 if (NG_NODE_NOT_VALID(node)) {
2420 TRAP_ERROR();
2421 error = EINVAL;
2422 NG_FREE_ITEM(item);
2423 break;
2424 }
2425 /*
2426 * Call the appropriate message handler for the object.
2427 * It is up to the message handler to free the message.
2428 * If it's a generic message, handle it generically,
2429 * otherwise call the type's message handler (if it exists).
2430 * XXX (race). Remember that a queued message may
2431 * reference a node or hook that has just been
2432 * invalidated. It will exist as the queue code
2433 * is holding a reference, but..
2434 */
2435 if ((NGI_MSG(item)->header.typecookie == NGM_GENERIC_COOKIE) &&
2436 ((NGI_MSG(item)->header.flags & NGF_RESP) == 0)) {
2437 error = ng_generic_msg(node, item, hook);
2438 break;
2439 }
2440 if (((!hook) || (!(rcvmsg = hook->hk_rcvmsg))) &&
2441 (!(rcvmsg = node->nd_type->rcvmsg))) {
2442 TRAP_ERROR();
2443 error = 0;
2444 NG_FREE_ITEM(item);
2445 break;
2446 }
2447 error = (*rcvmsg)(node, item, hook);
2448 break;
2449 case NGQF_FN:
2450 case NGQF_FN2:
2451 /*
2452 * In the case of the shutdown message we allow it to hit
2453 * even if the node is invalid.
2454 */
2455 if (NG_NODE_NOT_VALID(node) &&
2456 NGI_FN(item) != &ng_rmnode) {
2457 TRAP_ERROR();
2458 error = EINVAL;
2459 NG_FREE_ITEM(item);
2460 break;
2461 }
2462 /* Same is about some internal functions and invalid hook. */
2463 if (hook && NG_HOOK_NOT_VALID(hook) &&
2464 NGI_FN2(item) != &ng_con_part2 &&
2465 NGI_FN2(item) != &ng_con_part3 &&
2466 NGI_FN(item) != &ng_rmhook_part2) {
2467 TRAP_ERROR();
2468 error = EINVAL;
2469 NG_FREE_ITEM(item);
2470 break;
2471 }
2472
2473 if ((item->el_flags & NGQF_TYPE) == NGQF_FN) {
2474 (*NGI_FN(item))(node, hook, NGI_ARG1(item),
2475 NGI_ARG2(item));
2476 NG_FREE_ITEM(item);
2477 } else /* it is NGQF_FN2 */
2478 error = (*NGI_FN2(item))(node, item, hook);
2479 break;
2480 }
2481 /*
2482 * We held references on some of the resources
2483 * that we took from the item. Now that we have
2484 * finished doing everything, drop those references.
2485 */
2486 if (hook)
2487 NG_HOOK_UNREF(hook);
2488
2489 if (rw == NGQRW_R)
2490 ng_leave_read(node);
2491 else
2492 ng_leave_write(node);
2493
2494 /* Apply callback. */
2495 if (apply != NULL) {
2496 if (depth == 1 && error != 0)
2497 apply->error = error;
2498 if (refcount_release(&apply->refs))
2499 (*apply->apply)(apply->context, apply->error);
2500 }
2501
2502 return (error);
2503 }
2504
2505 /***********************************************************************
2506 * Implement the 'generic' control messages
2507 ***********************************************************************/
2508 static int
2509 ng_generic_msg(node_p here, item_p item, hook_p lasthook)
2510 {
2511 int error = 0;
2512 struct ng_mesg *msg;
2513 struct ng_mesg *resp = NULL;
2514
2515 NGI_GET_MSG(item, msg);
2516 if (msg->header.typecookie != NGM_GENERIC_COOKIE) {
2517 TRAP_ERROR();
2518 error = EINVAL;
2519 goto out;
2520 }
2521 switch (msg->header.cmd) {
2522 case NGM_SHUTDOWN:
2523 ng_rmnode(here, NULL, NULL, 0);
2524 break;
2525 case NGM_MKPEER:
2526 {
2527 struct ngm_mkpeer *const mkp = (struct ngm_mkpeer *) msg->data;
2528
2529 if (msg->header.arglen != sizeof(*mkp)) {
2530 TRAP_ERROR();
2531 error = EINVAL;
2532 break;
2533 }
2534 mkp->type[sizeof(mkp->type) - 1] = '\0';
2535 mkp->ourhook[sizeof(mkp->ourhook) - 1] = '\0';
2536 mkp->peerhook[sizeof(mkp->peerhook) - 1] = '\0';
2537 error = ng_mkpeer(here, mkp->ourhook, mkp->peerhook, mkp->type);
2538 break;
2539 }
2540 case NGM_CONNECT:
2541 {
2542 struct ngm_connect *const con =
2543 (struct ngm_connect *) msg->data;
2544 node_p node2;
2545
2546 if (msg->header.arglen != sizeof(*con)) {
2547 TRAP_ERROR();
2548 error = EINVAL;
2549 break;
2550 }
2551 con->path[sizeof(con->path) - 1] = '\0';
2552 con->ourhook[sizeof(con->ourhook) - 1] = '\0';
2553 con->peerhook[sizeof(con->peerhook) - 1] = '\0';
2554 /* Don't forget we get a reference.. */
2555 error = ng_path2noderef(here, con->path, &node2, NULL);
2556 if (error)
2557 break;
2558 error = ng_con_nodes(item, here, con->ourhook,
2559 node2, con->peerhook);
2560 NG_NODE_UNREF(node2);
2561 break;
2562 }
2563 case NGM_NAME:
2564 {
2565 struct ngm_name *const nam = (struct ngm_name *) msg->data;
2566
2567 if (msg->header.arglen != sizeof(*nam)) {
2568 TRAP_ERROR();
2569 error = EINVAL;
2570 break;
2571 }
2572 nam->name[sizeof(nam->name) - 1] = '\0';
2573 error = ng_name_node(here, nam->name);
2574 break;
2575 }
2576 case NGM_RMHOOK:
2577 {
2578 struct ngm_rmhook *const rmh = (struct ngm_rmhook *) msg->data;
2579 hook_p hook;
2580
2581 if (msg->header.arglen != sizeof(*rmh)) {
2582 TRAP_ERROR();
2583 error = EINVAL;
2584 break;
2585 }
2586 rmh->ourhook[sizeof(rmh->ourhook) - 1] = '\0';
2587 if ((hook = ng_findhook(here, rmh->ourhook)) != NULL)
2588 ng_destroy_hook(hook);
2589 break;
2590 }
2591 case NGM_NODEINFO:
2592 {
2593 struct nodeinfo *ni;
2594
2595 NG_MKRESPONSE(resp, msg, sizeof(*ni), M_NOWAIT);
2596 if (resp == NULL) {
2597 error = ENOMEM;
2598 break;
2599 }
2600
2601 /* Fill in node info */
2602 ni = (struct nodeinfo *) resp->data;
2603 if (NG_NODE_HAS_NAME(here))
2604 strcpy(ni->name, NG_NODE_NAME(here));
2605 strcpy(ni->type, here->nd_type->name);
2606 ni->id = ng_node2ID(here);
2607 ni->hooks = here->nd_numhooks;
2608 break;
2609 }
2610 case NGM_LISTHOOKS:
2611 {
2612 const int nhooks = here->nd_numhooks;
2613 struct hooklist *hl;
2614 struct nodeinfo *ni;
2615 hook_p hook;
2616
2617 /* Get response struct */
2618 NG_MKRESPONSE(resp, msg, sizeof(*hl) +
2619 (nhooks * sizeof(struct linkinfo)), M_NOWAIT);
2620 if (resp == NULL) {
2621 error = ENOMEM;
2622 break;
2623 }
2624 hl = (struct hooklist *) resp->data;
2625 ni = &hl->nodeinfo;
2626
2627 /* Fill in node info */
2628 if (NG_NODE_HAS_NAME(here))
2629 strcpy(ni->name, NG_NODE_NAME(here));
2630 strcpy(ni->type, here->nd_type->name);
2631 ni->id = ng_node2ID(here);
2632
2633 /* Cycle through the linked list of hooks */
2634 ni->hooks = 0;
2635 LIST_FOREACH(hook, &here->nd_hooks, hk_hooks) {
2636 struct linkinfo *const link = &hl->link[ni->hooks];
2637
2638 if (ni->hooks >= nhooks) {
2639 log(LOG_ERR, "%s: number of %s changed\n",
2640 __func__, "hooks");
2641 break;
2642 }
2643 if (NG_HOOK_NOT_VALID(hook))
2644 continue;
2645 strcpy(link->ourhook, NG_HOOK_NAME(hook));
2646 strcpy(link->peerhook, NG_PEER_HOOK_NAME(hook));
2647 if (NG_PEER_NODE_NAME(hook)[0] != '\0')
2648 strcpy(link->nodeinfo.name,
2649 NG_PEER_NODE_NAME(hook));
2650 strcpy(link->nodeinfo.type,
2651 NG_PEER_NODE(hook)->nd_type->name);
2652 link->nodeinfo.id = ng_node2ID(NG_PEER_NODE(hook));
2653 link->nodeinfo.hooks = NG_PEER_NODE(hook)->nd_numhooks;
2654 ni->hooks++;
2655 }
2656 break;
2657 }
2658
2659 case NGM_LISTNODES:
2660 {
2661 struct namelist *nl;
2662 node_p node;
2663 int i;
2664
2665 IDHASH_RLOCK();
2666 /* Get response struct. */
2667 NG_MKRESPONSE(resp, msg, sizeof(*nl) +
2668 (V_ng_nodes * sizeof(struct nodeinfo)), M_NOWAIT | M_ZERO);
2669 if (resp == NULL) {
2670 IDHASH_RUNLOCK();
2671 error = ENOMEM;
2672 break;
2673 }
2674 nl = (struct namelist *) resp->data;
2675
2676 /* Cycle through the lists of nodes. */
2677 nl->numnames = 0;
2678 for (i = 0; i <= V_ng_ID_hmask; i++) {
2679 LIST_FOREACH(node, &V_ng_ID_hash[i], nd_idnodes) {
2680 struct nodeinfo *const np =
2681 &nl->nodeinfo[nl->numnames];
2682
2683 if (NG_NODE_NOT_VALID(node))
2684 continue;
2685 if (NG_NODE_HAS_NAME(node))
2686 strcpy(np->name, NG_NODE_NAME(node));
2687 strcpy(np->type, node->nd_type->name);
2688 np->id = ng_node2ID(node);
2689 np->hooks = node->nd_numhooks;
2690 KASSERT(nl->numnames < V_ng_nodes,
2691 ("%s: no space", __func__));
2692 nl->numnames++;
2693 }
2694 }
2695 IDHASH_RUNLOCK();
2696 break;
2697 }
2698 case NGM_LISTNAMES:
2699 {
2700 struct namelist *nl;
2701 node_p node;
2702 int i;
2703
2704 NAMEHASH_RLOCK();
2705 /* Get response struct. */
2706 NG_MKRESPONSE(resp, msg, sizeof(*nl) +
2707 (V_ng_named_nodes * sizeof(struct nodeinfo)), M_NOWAIT);
2708 if (resp == NULL) {
2709 NAMEHASH_RUNLOCK();
2710 error = ENOMEM;
2711 break;
2712 }
2713 nl = (struct namelist *) resp->data;
2714
2715 /* Cycle through the lists of nodes. */
2716 nl->numnames = 0;
2717 for (i = 0; i <= V_ng_name_hmask; i++) {
2718 LIST_FOREACH(node, &V_ng_name_hash[i], nd_nodes) {
2719 struct nodeinfo *const np =
2720 &nl->nodeinfo[nl->numnames];
2721
2722 if (NG_NODE_NOT_VALID(node))
2723 continue;
2724 strcpy(np->name, NG_NODE_NAME(node));
2725 strcpy(np->type, node->nd_type->name);
2726 np->id = ng_node2ID(node);
2727 np->hooks = node->nd_numhooks;
2728 KASSERT(nl->numnames < V_ng_named_nodes,
2729 ("%s: no space", __func__));
2730 nl->numnames++;
2731 }
2732 }
2733 NAMEHASH_RUNLOCK();
2734 break;
2735 }
2736
2737 case NGM_LISTTYPES:
2738 {
2739 struct typelist *tl;
2740 struct ng_type *type;
2741 int num = 0;
2742
2743 TYPELIST_RLOCK();
2744 /* Count number of types */
2745 LIST_FOREACH(type, &ng_typelist, types)
2746 num++;
2747
2748 /* Get response struct */
2749 NG_MKRESPONSE(resp, msg, sizeof(*tl) +
2750 (num * sizeof(struct typeinfo)), M_NOWAIT);
2751 if (resp == NULL) {
2752 TYPELIST_RUNLOCK();
2753 error = ENOMEM;
2754 break;
2755 }
2756 tl = (struct typelist *) resp->data;
2757
2758 /* Cycle through the linked list of types */
2759 tl->numtypes = 0;
2760 LIST_FOREACH(type, &ng_typelist, types) {
2761 struct typeinfo *const tp = &tl->typeinfo[tl->numtypes];
2762
2763 strcpy(tp->type_name, type->name);
2764 tp->numnodes = type->refs - 1; /* don't count list */
2765 KASSERT(tl->numtypes < num, ("%s: no space", __func__));
2766 tl->numtypes++;
2767 }
2768 TYPELIST_RUNLOCK();
2769 break;
2770 }
2771
2772 case NGM_BINARY2ASCII:
2773 {
2774 int bufSize = 20 * 1024; /* XXX hard coded constant */
2775 const struct ng_parse_type *argstype;
2776 const struct ng_cmdlist *c;
2777 struct ng_mesg *binary, *ascii;
2778
2779 /* Data area must contain a valid netgraph message */
2780 binary = (struct ng_mesg *)msg->data;
2781 if (msg->header.arglen < sizeof(struct ng_mesg) ||
2782 (msg->header.arglen - sizeof(struct ng_mesg) <
2783 binary->header.arglen)) {
2784 TRAP_ERROR();
2785 error = EINVAL;
2786 break;
2787 }
2788
2789 /* Get a response message with lots of room */
2790 NG_MKRESPONSE(resp, msg, sizeof(*ascii) + bufSize, M_NOWAIT);
2791 if (resp == NULL) {
2792 error = ENOMEM;
2793 break;
2794 }
2795 ascii = (struct ng_mesg *)resp->data;
2796
2797 /* Copy binary message header to response message payload */
2798 bcopy(binary, ascii, sizeof(*binary));
2799
2800 /* Find command by matching typecookie and command number */
2801 for (c = here->nd_type->cmdlist; c != NULL && c->name != NULL;
2802 c++) {
2803 if (binary->header.typecookie == c->cookie &&
2804 binary->header.cmd == c->cmd)
2805 break;
2806 }
2807 if (c == NULL || c->name == NULL) {
2808 for (c = ng_generic_cmds; c->name != NULL; c++) {
2809 if (binary->header.typecookie == c->cookie &&
2810 binary->header.cmd == c->cmd)
2811 break;
2812 }
2813 if (c->name == NULL) {
2814 NG_FREE_MSG(resp);
2815 error = ENOSYS;
2816 break;
2817 }
2818 }
2819
2820 /* Convert command name to ASCII */
2821 snprintf(ascii->header.cmdstr, sizeof(ascii->header.cmdstr),
2822 "%s", c->name);
2823
2824 /* Convert command arguments to ASCII */
2825 argstype = (binary->header.flags & NGF_RESP) ?
2826 c->respType : c->mesgType;
2827 if (argstype == NULL) {
2828 *ascii->data = '\0';
2829 } else {
2830 if ((error = ng_unparse(argstype,
2831 (u_char *)binary->data,
2832 ascii->data, bufSize)) != 0) {
2833 NG_FREE_MSG(resp);
2834 break;
2835 }
2836 }
2837
2838 /* Return the result as struct ng_mesg plus ASCII string */
2839 bufSize = strlen(ascii->data) + 1;
2840 ascii->header.arglen = bufSize;
2841 resp->header.arglen = sizeof(*ascii) + bufSize;
2842 break;
2843 }
2844
2845 case NGM_ASCII2BINARY:
2846 {
2847 int bufSize = 20 * 1024; /* XXX hard coded constant */
2848 const struct ng_cmdlist *c;
2849 const struct ng_parse_type *argstype;
2850 struct ng_mesg *ascii, *binary;
2851 int off = 0;
2852
2853 /* Data area must contain at least a struct ng_mesg + '\0' */
2854 ascii = (struct ng_mesg *)msg->data;
2855 if ((msg->header.arglen < sizeof(*ascii) + 1) ||
2856 (ascii->header.arglen < 1) ||
2857 (msg->header.arglen < sizeof(*ascii) +
2858 ascii->header.arglen)) {
2859 TRAP_ERROR();
2860 error = EINVAL;
2861 break;
2862 }
2863 ascii->data[ascii->header.arglen - 1] = '\0';
2864
2865 /* Get a response message with lots of room */
2866 NG_MKRESPONSE(resp, msg, sizeof(*binary) + bufSize, M_NOWAIT);
2867 if (resp == NULL) {
2868 error = ENOMEM;
2869 break;
2870 }
2871 binary = (struct ng_mesg *)resp->data;
2872
2873 /* Copy ASCII message header to response message payload */
2874 bcopy(ascii, binary, sizeof(*ascii));
2875
2876 /* Find command by matching ASCII command string */
2877 for (c = here->nd_type->cmdlist;
2878 c != NULL && c->name != NULL; c++) {
2879 if (strcmp(ascii->header.cmdstr, c->name) == 0)
2880 break;
2881 }
2882 if (c == NULL || c->name == NULL) {
2883 for (c = ng_generic_cmds; c->name != NULL; c++) {
2884 if (strcmp(ascii->header.cmdstr, c->name) == 0)
2885 break;
2886 }
2887 if (c->name == NULL) {
2888 NG_FREE_MSG(resp);
2889 error = ENOSYS;
2890 break;
2891 }
2892 }
2893
2894 /* Convert command name to binary */
2895 binary->header.cmd = c->cmd;
2896 binary->header.typecookie = c->cookie;
2897
2898 /* Convert command arguments to binary */
2899 argstype = (binary->header.flags & NGF_RESP) ?
2900 c->respType : c->mesgType;
2901 if (argstype == NULL) {
2902 bufSize = 0;
2903 } else {
2904 if ((error = ng_parse(argstype, ascii->data, &off,
2905 (u_char *)binary->data, &bufSize)) != 0) {
2906 NG_FREE_MSG(resp);
2907 break;
2908 }
2909 }
2910
2911 /* Return the result */
2912 binary->header.arglen = bufSize;
2913 resp->header.arglen = sizeof(*binary) + bufSize;
2914 break;
2915 }
2916
2917 case NGM_TEXT_CONFIG:
2918 case NGM_TEXT_STATUS:
2919 /*
2920 * This one is tricky as it passes the command down to the
2921 * actual node, even though it is a generic type command.
2922 * This means we must assume that the item/msg is already freed
2923 * when control passes back to us.
2924 */
2925 if (here->nd_type->rcvmsg != NULL) {
2926 NGI_MSG(item) = msg; /* put it back as we found it */
2927 return((*here->nd_type->rcvmsg)(here, item, lasthook));
2928 }
2929 /* Fall through if rcvmsg not supported */
2930 default:
2931 TRAP_ERROR();
2932 error = EINVAL;
2933 }
2934 /*
2935 * Sometimes a generic message may be statically allocated
2936 * to avoid problems with allocating when in tight memory situations.
2937 * Don't free it if it is so.
2938 * I break them apart here, because erros may cause a free if the item
2939 * in which case we'd be doing it twice.
2940 * they are kept together above, to simplify freeing.
2941 */
2942 out:
2943 NG_RESPOND_MSG(error, here, item, resp);
2944 NG_FREE_MSG(msg);
2945 return (error);
2946 }
2947
2948 /************************************************************************
2949 Queue element get/free routines
2950 ************************************************************************/
2951
2952 uma_zone_t ng_qzone;
2953 uma_zone_t ng_qdzone;
2954 static int numthreads = 0; /* number of queue threads */
2955 static int maxalloc = 4096;/* limit the damage of a leak */
2956 static int maxdata = 4096; /* limit the damage of a DoS */
2957
2958 SYSCTL_INT(_net_graph, OID_AUTO, threads, CTLFLAG_RDTUN, &numthreads,
2959 0, "Number of queue processing threads");
2960 SYSCTL_INT(_net_graph, OID_AUTO, maxalloc, CTLFLAG_RDTUN, &maxalloc,
2961 0, "Maximum number of non-data queue items to allocate");
2962 SYSCTL_INT(_net_graph, OID_AUTO, maxdata, CTLFLAG_RDTUN, &maxdata,
2963 0, "Maximum number of data queue items to allocate");
2964
2965 #ifdef NETGRAPH_DEBUG
2966 static TAILQ_HEAD(, ng_item) ng_itemlist = TAILQ_HEAD_INITIALIZER(ng_itemlist);
2967 static int allocated; /* number of items malloc'd */
2968 #endif
2969
2970 /*
2971 * Get a queue entry.
2972 * This is usually called when a packet first enters netgraph.
2973 * By definition, this is usually from an interrupt, or from a user.
2974 * Users are not so important, but try be quick for the times that it's
2975 * an interrupt.
2976 */
2977 static __inline item_p
2978 ng_alloc_item(int type, int flags)
2979 {
2980 item_p item;
2981
2982 KASSERT(((type & ~NGQF_TYPE) == 0),
2983 ("%s: incorrect item type: %d", __func__, type));
2984
2985 item = uma_zalloc((type == NGQF_DATA) ? ng_qdzone : ng_qzone,
2986 ((flags & NG_WAITOK) ? M_WAITOK : M_NOWAIT) | M_ZERO);
2987
2988 if (item) {
2989 item->el_flags = type;
2990 #ifdef NETGRAPH_DEBUG
2991 mtx_lock(&ngq_mtx);
2992 TAILQ_INSERT_TAIL(&ng_itemlist, item, all);
2993 allocated++;
2994 mtx_unlock(&ngq_mtx);
2995 #endif
2996 }
2997
2998 return (item);
2999 }
3000
3001 /*
3002 * Release a queue entry
3003 */
3004 void
3005 ng_free_item(item_p item)
3006 {
3007 /*
3008 * The item may hold resources on it's own. We need to free
3009 * these before we can free the item. What they are depends upon
3010 * what kind of item it is. it is important that nodes zero
3011 * out pointers to resources that they remove from the item
3012 * or we release them again here.
3013 */
3014 switch (item->el_flags & NGQF_TYPE) {
3015 case NGQF_DATA:
3016 /* If we have an mbuf still attached.. */
3017 NG_FREE_M(_NGI_M(item));
3018 break;
3019 case NGQF_MESG:
3020 _NGI_RETADDR(item) = 0;
3021 NG_FREE_MSG(_NGI_MSG(item));
3022 break;
3023 case NGQF_FN:
3024 case NGQF_FN2:
3025 /* nothing to free really, */
3026 _NGI_FN(item) = NULL;
3027 _NGI_ARG1(item) = NULL;
3028 _NGI_ARG2(item) = 0;
3029 break;
3030 }
3031 /* If we still have a node or hook referenced... */
3032 _NGI_CLR_NODE(item);
3033 _NGI_CLR_HOOK(item);
3034
3035 #ifdef NETGRAPH_DEBUG
3036 mtx_lock(&ngq_mtx);
3037 TAILQ_REMOVE(&ng_itemlist, item, all);
3038 allocated--;
3039 mtx_unlock(&ngq_mtx);
3040 #endif
3041 uma_zfree(((item->el_flags & NGQF_TYPE) == NGQF_DATA) ?
3042 ng_qdzone : ng_qzone, item);
3043 }
3044
3045 /*
3046 * Change type of the queue entry.
3047 * Possibly reallocates it from another UMA zone.
3048 */
3049 static __inline item_p
3050 ng_realloc_item(item_p pitem, int type, int flags)
3051 {
3052 item_p item;
3053 int from, to;
3054
3055 KASSERT((pitem != NULL), ("%s: can't reallocate NULL", __func__));
3056 KASSERT(((type & ~NGQF_TYPE) == 0),
3057 ("%s: incorrect item type: %d", __func__, type));
3058
3059 from = ((pitem->el_flags & NGQF_TYPE) == NGQF_DATA);
3060 to = (type == NGQF_DATA);
3061 if (from != to) {
3062 /* If reallocation is required do it and copy item. */
3063 if ((item = ng_alloc_item(type, flags)) == NULL) {
3064 ng_free_item(pitem);
3065 return (NULL);
3066 }
3067 *item = *pitem;
3068 ng_free_item(pitem);
3069 } else
3070 item = pitem;
3071 item->el_flags = (item->el_flags & ~NGQF_TYPE) | type;
3072
3073 return (item);
3074 }
3075
3076 /************************************************************************
3077 Module routines
3078 ************************************************************************/
3079
3080 /*
3081 * Handle the loading/unloading of a netgraph node type module
3082 */
3083 int
3084 ng_mod_event(module_t mod, int event, void *data)
3085 {
3086 struct ng_type *const type = data;
3087 int error = 0;
3088
3089 switch (event) {
3090 case MOD_LOAD:
3091
3092 /* Register new netgraph node type */
3093 if ((error = ng_newtype(type)) != 0)
3094 break;
3095
3096 /* Call type specific code */
3097 if (type->mod_event != NULL)
3098 if ((error = (*type->mod_event)(mod, event, data))) {
3099 TYPELIST_WLOCK();
3100 type->refs--; /* undo it */
3101 LIST_REMOVE(type, types);
3102 TYPELIST_WUNLOCK();
3103 }
3104 break;
3105
3106 case MOD_UNLOAD:
3107 if (type->refs > 1) { /* make sure no nodes exist! */
3108 error = EBUSY;
3109 } else {
3110 if (type->refs == 0) /* failed load, nothing to undo */
3111 break;
3112 if (type->mod_event != NULL) { /* check with type */
3113 error = (*type->mod_event)(mod, event, data);
3114 if (error != 0) /* type refuses.. */
3115 break;
3116 }
3117 TYPELIST_WLOCK();
3118 LIST_REMOVE(type, types);
3119 TYPELIST_WUNLOCK();
3120 }
3121 break;
3122
3123 default:
3124 if (type->mod_event != NULL)
3125 error = (*type->mod_event)(mod, event, data);
3126 else
3127 error = EOPNOTSUPP; /* XXX ? */
3128 break;
3129 }
3130 return (error);
3131 }
3132
3133 static void
3134 vnet_netgraph_init(const void *unused __unused)
3135 {
3136
3137 /* We start with small hashes, but they can grow. */
3138 V_ng_ID_hash = hashinit(16, M_NETGRAPH_NODE, &V_ng_ID_hmask);
3139 V_ng_name_hash = hashinit(16, M_NETGRAPH_NODE, &V_ng_name_hmask);
3140 }
3141 VNET_SYSINIT(vnet_netgraph_init, SI_SUB_NETGRAPH, SI_ORDER_FIRST,
3142 vnet_netgraph_init, NULL);
3143
3144 #ifdef VIMAGE
3145 static void
3146 vnet_netgraph_uninit(const void *unused __unused)
3147 {
3148 node_p node = NULL, last_killed = NULL;
3149 int i;
3150
3151 do {
3152 /* Find a node to kill */
3153 IDHASH_RLOCK();
3154 for (i = 0; i <= V_ng_ID_hmask; i++) {
3155 LIST_FOREACH(node, &V_ng_ID_hash[i], nd_idnodes) {
3156 if (node != &ng_deadnode) {
3157 NG_NODE_REF(node);
3158 break;
3159 }
3160 }
3161 if (node != NULL)
3162 break;
3163 }
3164 IDHASH_RUNLOCK();
3165
3166 /* Attempt to kill it only if it is a regular node */
3167 if (node != NULL) {
3168 if (node == last_killed) {
3169 /* This should never happen */
3170 printf("ng node %s needs NGF_REALLY_DIE\n",
3171 node->nd_name);
3172 if (node->nd_flags & NGF_REALLY_DIE)
3173 panic("ng node %s won't die",
3174 node->nd_name);
3175 node->nd_flags |= NGF_REALLY_DIE;
3176 }
3177 ng_rmnode(node, NULL, NULL, 0);
3178 NG_NODE_UNREF(node);
3179 last_killed = node;
3180 }
3181 } while (node != NULL);
3182
3183 hashdestroy(V_ng_name_hash, M_NETGRAPH_NODE, V_ng_name_hmask);
3184 hashdestroy(V_ng_ID_hash, M_NETGRAPH_NODE, V_ng_ID_hmask);
3185 }
3186 VNET_SYSUNINIT(vnet_netgraph_uninit, SI_SUB_NETGRAPH, SI_ORDER_FIRST,
3187 vnet_netgraph_uninit, NULL);
3188 #endif /* VIMAGE */
3189
3190 /*
3191 * Handle loading and unloading for this code.
3192 * The only thing we need to link into is the NETISR strucure.
3193 */
3194 static int
3195 ngb_mod_event(module_t mod, int event, void *data)
3196 {
3197 struct proc *p;
3198 struct thread *td;
3199 int i, error = 0;
3200
3201 switch (event) {
3202 case MOD_LOAD:
3203 /* Initialize everything. */
3204 NG_WORKLIST_LOCK_INIT();
3205 rw_init(&ng_typelist_lock, "netgraph types");
3206 rw_init(&ng_idhash_lock, "netgraph idhash");
3207 rw_init(&ng_namehash_lock, "netgraph namehash");
3208 rw_init(&ng_topo_lock, "netgraph topology mutex");
3209 #ifdef NETGRAPH_DEBUG
3210 mtx_init(&ng_nodelist_mtx, "netgraph nodelist mutex", NULL,
3211 MTX_DEF);
3212 mtx_init(&ngq_mtx, "netgraph item list mutex", NULL,
3213 MTX_DEF);
3214 #endif
3215 ng_qzone = uma_zcreate("NetGraph items", sizeof(struct ng_item),
3216 NULL, NULL, NULL, NULL, UMA_ALIGN_CACHE, 0);
3217 uma_zone_set_max(ng_qzone, maxalloc);
3218 ng_qdzone = uma_zcreate("NetGraph data items",
3219 sizeof(struct ng_item), NULL, NULL, NULL, NULL,
3220 UMA_ALIGN_CACHE, 0);
3221 uma_zone_set_max(ng_qdzone, maxdata);
3222 /* Autoconfigure number of threads. */
3223 if (numthreads <= 0)
3224 numthreads = mp_ncpus;
3225 /* Create threads. */
3226 p = NULL; /* start with no process */
3227 for (i = 0; i < numthreads; i++) {
3228 if (kproc_kthread_add(ngthread, NULL, &p, &td,
3229 RFHIGHPID, 0, "ng_queue", "ng_queue%d", i)) {
3230 numthreads = i;
3231 break;
3232 }
3233 }
3234 break;
3235 case MOD_UNLOAD:
3236 /* You can't unload it because an interface may be using it. */
3237 error = EBUSY;
3238 break;
3239 default:
3240 error = EOPNOTSUPP;
3241 break;
3242 }
3243 return (error);
3244 }
3245
3246 static moduledata_t netgraph_mod = {
3247 "netgraph",
3248 ngb_mod_event,
3249 (NULL)
3250 };
3251 DECLARE_MODULE(netgraph, netgraph_mod, SI_SUB_NETGRAPH, SI_ORDER_FIRST);
3252 SYSCTL_NODE(_net, OID_AUTO, graph, CTLFLAG_RW, 0, "netgraph Family");
3253 SYSCTL_INT(_net_graph, OID_AUTO, abi_version, CTLFLAG_RD, SYSCTL_NULL_INT_PTR, NG_ABI_VERSION,"");
3254 SYSCTL_INT(_net_graph, OID_AUTO, msg_version, CTLFLAG_RD, SYSCTL_NULL_INT_PTR, NG_VERSION, "");
3255
3256 #ifdef NETGRAPH_DEBUG
3257 void
3258 dumphook (hook_p hook, char *file, int line)
3259 {
3260 printf("hook: name %s, %d refs, Last touched:\n",
3261 _NG_HOOK_NAME(hook), hook->hk_refs);
3262 printf(" Last active @ %s, line %d\n",
3263 hook->lastfile, hook->lastline);
3264 if (line) {
3265 printf(" problem discovered at file %s, line %d\n", file, line);
3266 #ifdef KDB
3267 kdb_backtrace();
3268 #endif
3269 }
3270 }
3271
3272 void
3273 dumpnode(node_p node, char *file, int line)
3274 {
3275 printf("node: ID [%x]: type '%s', %d hooks, flags 0x%x, %d refs, %s:\n",
3276 _NG_NODE_ID(node), node->nd_type->name,
3277 node->nd_numhooks, node->nd_flags,
3278 node->nd_refs, node->nd_name);
3279 printf(" Last active @ %s, line %d\n",
3280 node->lastfile, node->lastline);
3281 if (line) {
3282 printf(" problem discovered at file %s, line %d\n", file, line);
3283 #ifdef KDB
3284 kdb_backtrace();
3285 #endif
3286 }
3287 }
3288
3289 void
3290 dumpitem(item_p item, char *file, int line)
3291 {
3292 printf(" ACTIVE item, last used at %s, line %d",
3293 item->lastfile, item->lastline);
3294 switch(item->el_flags & NGQF_TYPE) {
3295 case NGQF_DATA:
3296 printf(" - [data]\n");
3297 break;
3298 case NGQF_MESG:
3299 printf(" - retaddr[%d]:\n", _NGI_RETADDR(item));
3300 break;
3301 case NGQF_FN:
3302 printf(" - fn@%p (%p, %p, %p, %d (%x))\n",
3303 _NGI_FN(item),
3304 _NGI_NODE(item),
3305 _NGI_HOOK(item),
3306 item->body.fn.fn_arg1,
3307 item->body.fn.fn_arg2,
3308 item->body.fn.fn_arg2);
3309 break;
3310 case NGQF_FN2:
3311 printf(" - fn2@%p (%p, %p, %p, %d (%x))\n",
3312 _NGI_FN2(item),
3313 _NGI_NODE(item),
3314 _NGI_HOOK(item),
3315 item->body.fn.fn_arg1,
3316 item->body.fn.fn_arg2,
3317 item->body.fn.fn_arg2);
3318 break;
3319 }
3320 if (line) {
3321 printf(" problem discovered at file %s, line %d\n", file, line);
3322 if (_NGI_NODE(item)) {
3323 printf("node %p ([%x])\n",
3324 _NGI_NODE(item), ng_node2ID(_NGI_NODE(item)));
3325 }
3326 }
3327 }
3328
3329 static void
3330 ng_dumpitems(void)
3331 {
3332 item_p item;
3333 int i = 1;
3334 TAILQ_FOREACH(item, &ng_itemlist, all) {
3335 printf("[%d] ", i++);
3336 dumpitem(item, NULL, 0);
3337 }
3338 }
3339
3340 static void
3341 ng_dumpnodes(void)
3342 {
3343 node_p node;
3344 int i = 1;
3345 mtx_lock(&ng_nodelist_mtx);
3346 SLIST_FOREACH(node, &ng_allnodes, nd_all) {
3347 printf("[%d] ", i++);
3348 dumpnode(node, NULL, 0);
3349 }
3350 mtx_unlock(&ng_nodelist_mtx);
3351 }
3352
3353 static void
3354 ng_dumphooks(void)
3355 {
3356 hook_p hook;
3357 int i = 1;
3358 mtx_lock(&ng_nodelist_mtx);
3359 SLIST_FOREACH(hook, &ng_allhooks, hk_all) {
3360 printf("[%d] ", i++);
3361 dumphook(hook, NULL, 0);
3362 }
3363 mtx_unlock(&ng_nodelist_mtx);
3364 }
3365
3366 static int
3367 sysctl_debug_ng_dump_items(SYSCTL_HANDLER_ARGS)
3368 {
3369 int error;
3370 int val;
3371 int i;
3372
3373 val = allocated;
3374 i = 1;
3375 error = sysctl_handle_int(oidp, &val, 0, req);
3376 if (error != 0 || req->newptr == NULL)
3377 return (error);
3378 if (val == 42) {
3379 ng_dumpitems();
3380 ng_dumpnodes();
3381 ng_dumphooks();
3382 }
3383 return (0);
3384 }
3385
3386 SYSCTL_PROC(_debug, OID_AUTO, ng_dump_items, CTLTYPE_INT | CTLFLAG_RW,
3387 0, sizeof(int), sysctl_debug_ng_dump_items, "I", "Number of allocated items");
3388 #endif /* NETGRAPH_DEBUG */
3389
3390 /***********************************************************************
3391 * Worklist routines
3392 **********************************************************************/
3393 /*
3394 * Pick a node off the list of nodes with work,
3395 * try get an item to process off it. Remove the node from the list.
3396 */
3397 static void
3398 ngthread(void *arg)
3399 {
3400 for (;;) {
3401 node_p node;
3402
3403 /* Get node from the worklist. */
3404 NG_WORKLIST_LOCK();
3405 while ((node = STAILQ_FIRST(&ng_worklist)) == NULL)
3406 NG_WORKLIST_SLEEP();
3407 STAILQ_REMOVE_HEAD(&ng_worklist, nd_input_queue.q_work);
3408 NG_WORKLIST_UNLOCK();
3409 CURVNET_SET(node->nd_vnet);
3410 CTR3(KTR_NET, "%20s: node [%x] (%p) taken off worklist",
3411 __func__, node->nd_ID, node);
3412 /*
3413 * We have the node. We also take over the reference
3414 * that the list had on it.
3415 * Now process as much as you can, until it won't
3416 * let you have another item off the queue.
3417 * All this time, keep the reference
3418 * that lets us be sure that the node still exists.
3419 * Let the reference go at the last minute.
3420 */
3421 for (;;) {
3422 item_p item;
3423 int rw;
3424
3425 NG_QUEUE_LOCK(&node->nd_input_queue);
3426 item = ng_dequeue(node, &rw);
3427 if (item == NULL) {
3428 node->nd_input_queue.q_flags2 &= ~NGQ2_WORKQ;
3429 NG_QUEUE_UNLOCK(&node->nd_input_queue);
3430 break; /* go look for another node */
3431 } else {
3432 NG_QUEUE_UNLOCK(&node->nd_input_queue);
3433 NGI_GET_NODE(item, node); /* zaps stored node */
3434 ng_apply_item(node, item, rw);
3435 NG_NODE_UNREF(node);
3436 }
3437 }
3438 NG_NODE_UNREF(node);
3439 CURVNET_RESTORE();
3440 }
3441 }
3442
3443 /*
3444 * XXX
3445 * It's posible that a debugging NG_NODE_REF may need
3446 * to be outside the mutex zone
3447 */
3448 static void
3449 ng_worklist_add(node_p node)
3450 {
3451
3452 mtx_assert(&node->nd_input_queue.q_mtx, MA_OWNED);
3453
3454 if ((node->nd_input_queue.q_flags2 & NGQ2_WORKQ) == 0) {
3455 /*
3456 * If we are not already on the work queue,
3457 * then put us on.
3458 */
3459 node->nd_input_queue.q_flags2 |= NGQ2_WORKQ;
3460 NG_NODE_REF(node); /* XXX safe in mutex? */
3461 NG_WORKLIST_LOCK();
3462 STAILQ_INSERT_TAIL(&ng_worklist, node, nd_input_queue.q_work);
3463 NG_WORKLIST_UNLOCK();
3464 CTR3(KTR_NET, "%20s: node [%x] (%p) put on worklist", __func__,
3465 node->nd_ID, node);
3466 NG_WORKLIST_WAKEUP();
3467 } else {
3468 CTR3(KTR_NET, "%20s: node [%x] (%p) already on worklist",
3469 __func__, node->nd_ID, node);
3470 }
3471 }
3472
3473 /***********************************************************************
3474 * Externally useable functions to set up a queue item ready for sending
3475 ***********************************************************************/
3476
3477 #ifdef NETGRAPH_DEBUG
3478 #define ITEM_DEBUG_CHECKS \
3479 do { \
3480 if (NGI_NODE(item) ) { \
3481 printf("item already has node"); \
3482 kdb_enter(KDB_WHY_NETGRAPH, "has node"); \
3483 NGI_CLR_NODE(item); \
3484 } \
3485 if (NGI_HOOK(item) ) { \
3486 printf("item already has hook"); \
3487 kdb_enter(KDB_WHY_NETGRAPH, "has hook"); \
3488 NGI_CLR_HOOK(item); \
3489 } \
3490 } while (0)
3491 #else
3492 #define ITEM_DEBUG_CHECKS
3493 #endif
3494
3495 /*
3496 * Put mbuf into the item.
3497 * Hook and node references will be removed when the item is dequeued.
3498 * (or equivalent)
3499 * (XXX) Unsafe because no reference held by peer on remote node.
3500 * remote node might go away in this timescale.
3501 * We know the hooks can't go away because that would require getting
3502 * a writer item on both nodes and we must have at least a reader
3503 * here to be able to do this.
3504 * Note that the hook loaded is the REMOTE hook.
3505 *
3506 * This is possibly in the critical path for new data.
3507 */
3508 item_p
3509 ng_package_data(struct mbuf *m, int flags)
3510 {
3511 item_p item;
3512
3513 if ((item = ng_alloc_item(NGQF_DATA, flags)) == NULL) {
3514 NG_FREE_M(m);
3515 return (NULL);
3516 }
3517 ITEM_DEBUG_CHECKS;
3518 item->el_flags |= NGQF_READER;
3519 NGI_M(item) = m;
3520 return (item);
3521 }
3522
3523 /*
3524 * Allocate a queue item and put items into it..
3525 * Evaluate the address as this will be needed to queue it and
3526 * to work out what some of the fields should be.
3527 * Hook and node references will be removed when the item is dequeued.
3528 * (or equivalent)
3529 */
3530 item_p
3531 ng_package_msg(struct ng_mesg *msg, int flags)
3532 {
3533 item_p item;
3534
3535 if ((item = ng_alloc_item(NGQF_MESG, flags)) == NULL) {
3536 NG_FREE_MSG(msg);
3537 return (NULL);
3538 }
3539 ITEM_DEBUG_CHECKS;
3540 /* Messages items count as writers unless explicitly exempted. */
3541 if (msg->header.cmd & NGM_READONLY)
3542 item->el_flags |= NGQF_READER;
3543 else
3544 item->el_flags |= NGQF_WRITER;
3545 /*
3546 * Set the current lasthook into the queue item
3547 */
3548 NGI_MSG(item) = msg;
3549 NGI_RETADDR(item) = 0;
3550 return (item);
3551 }
3552
3553 #define SET_RETADDR(item, here, retaddr) \
3554 do { /* Data or fn items don't have retaddrs */ \
3555 if ((item->el_flags & NGQF_TYPE) == NGQF_MESG) { \
3556 if (retaddr) { \
3557 NGI_RETADDR(item) = retaddr; \
3558 } else { \
3559 /* \
3560 * The old return address should be ok. \
3561 * If there isn't one, use the address \
3562 * here. \
3563 */ \
3564 if (NGI_RETADDR(item) == 0) { \
3565 NGI_RETADDR(item) \
3566 = ng_node2ID(here); \
3567 } \
3568 } \
3569 } \
3570 } while (0)
3571
3572 int
3573 ng_address_hook(node_p here, item_p item, hook_p hook, ng_ID_t retaddr)
3574 {
3575 hook_p peer;
3576 node_p peernode;
3577 ITEM_DEBUG_CHECKS;
3578 /*
3579 * Quick sanity check..
3580 * Since a hook holds a reference on it's node, once we know
3581 * that the peer is still connected (even if invalid,) we know
3582 * that the peer node is present, though maybe invalid.
3583 */
3584 TOPOLOGY_RLOCK();
3585 if ((hook == NULL) || NG_HOOK_NOT_VALID(hook) ||
3586 NG_HOOK_NOT_VALID(peer = NG_HOOK_PEER(hook)) ||
3587 NG_NODE_NOT_VALID(peernode = NG_PEER_NODE(hook))) {
3588 NG_FREE_ITEM(item);
3589 TRAP_ERROR();
3590 TOPOLOGY_RUNLOCK();
3591 return (ENETDOWN);
3592 }
3593
3594 /*
3595 * Transfer our interest to the other (peer) end.
3596 */
3597 NG_HOOK_REF(peer);
3598 NG_NODE_REF(peernode);
3599 NGI_SET_HOOK(item, peer);
3600 NGI_SET_NODE(item, peernode);
3601 SET_RETADDR(item, here, retaddr);
3602
3603 TOPOLOGY_RUNLOCK();
3604
3605 return (0);
3606 }
3607
3608 int
3609 ng_address_path(node_p here, item_p item, const char *address, ng_ID_t retaddr)
3610 {
3611 node_p dest = NULL;
3612 hook_p hook = NULL;
3613 int error;
3614
3615 ITEM_DEBUG_CHECKS;
3616 /*
3617 * Note that ng_path2noderef increments the reference count
3618 * on the node for us if it finds one. So we don't have to.
3619 */
3620 error = ng_path2noderef(here, address, &dest, &hook);
3621 if (error) {
3622 NG_FREE_ITEM(item);
3623 return (error);
3624 }
3625 NGI_SET_NODE(item, dest);
3626 if (hook)
3627 NGI_SET_HOOK(item, hook);
3628
3629 SET_RETADDR(item, here, retaddr);
3630 return (0);
3631 }
3632
3633 int
3634 ng_address_ID(node_p here, item_p item, ng_ID_t ID, ng_ID_t retaddr)
3635 {
3636 node_p dest;
3637
3638 ITEM_DEBUG_CHECKS;
3639 /*
3640 * Find the target node.
3641 */
3642 dest = ng_ID2noderef(ID); /* GETS REFERENCE! */
3643 if (dest == NULL) {
3644 NG_FREE_ITEM(item);
3645 TRAP_ERROR();
3646 return(EINVAL);
3647 }
3648 /* Fill out the contents */
3649 NGI_SET_NODE(item, dest);
3650 NGI_CLR_HOOK(item);
3651 SET_RETADDR(item, here, retaddr);
3652 return (0);
3653 }
3654
3655 /*
3656 * special case to send a message to self (e.g. destroy node)
3657 * Possibly indicate an arrival hook too.
3658 * Useful for removing that hook :-)
3659 */
3660 item_p
3661 ng_package_msg_self(node_p here, hook_p hook, struct ng_mesg *msg)
3662 {
3663 item_p item;
3664
3665 /*
3666 * Find the target node.
3667 * If there is a HOOK argument, then use that in preference
3668 * to the address.
3669 */
3670 if ((item = ng_alloc_item(NGQF_MESG, NG_NOFLAGS)) == NULL) {
3671 NG_FREE_MSG(msg);
3672 return (NULL);
3673 }
3674
3675 /* Fill out the contents */
3676 item->el_flags |= NGQF_WRITER;
3677 NG_NODE_REF(here);
3678 NGI_SET_NODE(item, here);
3679 if (hook) {
3680 NG_HOOK_REF(hook);
3681 NGI_SET_HOOK(item, hook);
3682 }
3683 NGI_MSG(item) = msg;
3684 NGI_RETADDR(item) = ng_node2ID(here);
3685 return (item);
3686 }
3687
3688 /*
3689 * Send ng_item_fn function call to the specified node.
3690 */
3691
3692 int
3693 ng_send_fn(node_p node, hook_p hook, ng_item_fn *fn, void * arg1, int arg2)
3694 {
3695
3696 return ng_send_fn1(node, hook, fn, arg1, arg2, NG_NOFLAGS);
3697 }
3698
3699 int
3700 ng_send_fn1(node_p node, hook_p hook, ng_item_fn *fn, void * arg1, int arg2,
3701 int flags)
3702 {
3703 item_p item;
3704
3705 if ((item = ng_alloc_item(NGQF_FN, flags)) == NULL) {
3706 return (ENOMEM);
3707 }
3708 item->el_flags |= NGQF_WRITER;
3709 NG_NODE_REF(node); /* and one for the item */
3710 NGI_SET_NODE(item, node);
3711 if (hook) {
3712 NG_HOOK_REF(hook);
3713 NGI_SET_HOOK(item, hook);
3714 }
3715 NGI_FN(item) = fn;
3716 NGI_ARG1(item) = arg1;
3717 NGI_ARG2(item) = arg2;
3718 return(ng_snd_item(item, flags));
3719 }
3720
3721 /*
3722 * Send ng_item_fn2 function call to the specified node.
3723 *
3724 * If an optional pitem parameter is supplied, its apply
3725 * callback will be copied to the new item. If also NG_REUSE_ITEM
3726 * flag is set, no new item will be allocated, but pitem will
3727 * be used.
3728 */
3729 int
3730 ng_send_fn2(node_p node, hook_p hook, item_p pitem, ng_item_fn2 *fn, void *arg1,
3731 int arg2, int flags)
3732 {
3733 item_p item;
3734
3735 KASSERT((pitem != NULL || (flags & NG_REUSE_ITEM) == 0),
3736 ("%s: NG_REUSE_ITEM but no pitem", __func__));
3737
3738 /*
3739 * Allocate a new item if no supplied or
3740 * if we can't use supplied one.
3741 */
3742 if (pitem == NULL || (flags & NG_REUSE_ITEM) == 0) {
3743 if ((item = ng_alloc_item(NGQF_FN2, flags)) == NULL)
3744 return (ENOMEM);
3745 if (pitem != NULL)
3746 item->apply = pitem->apply;
3747 } else {
3748 if ((item = ng_realloc_item(pitem, NGQF_FN2, flags)) == NULL)
3749 return (ENOMEM);
3750 }
3751
3752 item->el_flags = (item->el_flags & ~NGQF_RW) | NGQF_WRITER;
3753 NG_NODE_REF(node); /* and one for the item */
3754 NGI_SET_NODE(item, node);
3755 if (hook) {
3756 NG_HOOK_REF(hook);
3757 NGI_SET_HOOK(item, hook);
3758 }
3759 NGI_FN2(item) = fn;
3760 NGI_ARG1(item) = arg1;
3761 NGI_ARG2(item) = arg2;
3762 return(ng_snd_item(item, flags));
3763 }
3764
3765 /*
3766 * Official timeout routines for Netgraph nodes.
3767 */
3768 static void
3769 ng_callout_trampoline(void *arg)
3770 {
3771 item_p item = arg;
3772
3773 CURVNET_SET(NGI_NODE(item)->nd_vnet);
3774 ng_snd_item(item, 0);
3775 CURVNET_RESTORE();
3776 }
3777
3778 int
3779 ng_callout(struct callout *c, node_p node, hook_p hook, int ticks,
3780 ng_item_fn *fn, void * arg1, int arg2)
3781 {
3782 item_p item, oitem;
3783
3784 if ((item = ng_alloc_item(NGQF_FN, NG_NOFLAGS)) == NULL)
3785 return (ENOMEM);
3786
3787 item->el_flags |= NGQF_WRITER;
3788 NG_NODE_REF(node); /* and one for the item */
3789 NGI_SET_NODE(item, node);
3790 if (hook) {
3791 NG_HOOK_REF(hook);
3792 NGI_SET_HOOK(item, hook);
3793 }
3794 NGI_FN(item) = fn;
3795 NGI_ARG1(item) = arg1;
3796 NGI_ARG2(item) = arg2;
3797 oitem = c->c_arg;
3798 if (callout_reset(c, ticks, &ng_callout_trampoline, item) == 1 &&
3799 oitem != NULL)
3800 NG_FREE_ITEM(oitem);
3801 return (0);
3802 }
3803
3804 /* A special modified version of untimeout() */
3805 int
3806 ng_uncallout(struct callout *c, node_p node)
3807 {
3808 item_p item;
3809 int rval;
3810
3811 KASSERT(c != NULL, ("ng_uncallout: NULL callout"));
3812 KASSERT(node != NULL, ("ng_uncallout: NULL node"));
3813
3814 rval = callout_stop(c);
3815 item = c->c_arg;
3816 /* Do an extra check */
3817 if ((rval > 0) && (c->c_func == &ng_callout_trampoline) &&
3818 (item != NULL) && (NGI_NODE(item) == node)) {
3819 /*
3820 * We successfully removed it from the queue before it ran
3821 * So now we need to unreference everything that was
3822 * given extra references. (NG_FREE_ITEM does this).
3823 */
3824 NG_FREE_ITEM(item);
3825 }
3826 c->c_arg = NULL;
3827
3828 /*
3829 * Callers only want to know if the callout was cancelled and
3830 * not draining or stopped.
3831 */
3832 return (rval > 0);
3833 }
3834
3835 /*
3836 * Set the address, if none given, give the node here.
3837 */
3838 void
3839 ng_replace_retaddr(node_p here, item_p item, ng_ID_t retaddr)
3840 {
3841 if (retaddr) {
3842 NGI_RETADDR(item) = retaddr;
3843 } else {
3844 /*
3845 * The old return address should be ok.
3846 * If there isn't one, use the address here.
3847 */
3848 NGI_RETADDR(item) = ng_node2ID(here);
3849 }
3850 }
Cache object: 401620fb4bee0dc7360ecca238a621de
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