xref: /dragonfly/sys/netgraph7/netgraph/ng_base.c (revision 79dee9e91f9ecd90f4fa950300b6fd056a4ee953)
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: src/sys/netgraph/ng_base.c,v 1.159 2008/04/19 05:30:49 mav Exp $
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/errno.h>
49 #include <sys/hash.h>
50 /*#include <sys/kdb.h>*/
51 #include <sys/kernel.h>
52 #include <sys/limits.h>
53 #include <sys/malloc.h>
54 #include <sys/mbuf.h>
55 #include <sys/msgport2.h>
56 #include <sys/mutex2.h>
57 #include <sys/objcache.h>
58 #include <sys/proc.h>
59 #include <sys/queue.h>
60 #include <sys/refcount.h>
61 #include <sys/sysctl.h>
62 #include <sys/syslog.h>
63 #include <machine/cpu.h>
64 
65 #include <netgraph7/netgraph.h>
66 #include <netgraph7/netgraph2.h>
67 #include <netgraph7/ng_parse.h>
68 
69 MODULE_VERSION(netgraph, NG_ABI_VERSION);
70 
71 /* Token to protect topology events. */
72 static struct lwkt_token      ng_topo_token;
73 #define   TOPOLOGY_RLOCK()    lwkt_gettoken_shared(&ng_topo_token)
74 #define   TOPOLOGY_RUNLOCK()  lwkt_reltoken(&ng_topo_token)
75 #define   TOPOLOGY_WLOCK()    lwkt_gettoken(&ng_topo_token)
76 #define   TOPOLOGY_WUNLOCK()  lwkt_reltoken(&ng_topo_token)
77 #define   TOPOLOGY_NOTOWNED() KKASSERT(!LWKT_TOKEN_HELD_ANY(&ng_topo_token))
78 
79 #ifdef    NETGRAPH_DEBUG
80 static struct mtx   ng_nodelist_mtx; /* protects global node/hook lists */
81 static struct mtx   ngq_mtx;  /* protects the queue item list */
82 
83 static SLIST_HEAD(, ng_node) ng_allnodes;
84 static LIST_HEAD(, ng_node) ng_freenodes; /* in debug, we never free() them */
85 static SLIST_HEAD(, ng_hook) ng_allhooks;
86 static LIST_HEAD(, ng_hook) ng_freehooks; /* in debug, we never free() them */
87 
88 static void ng_dumpitems(void);
89 static void ng_dumpnodes(void);
90 static void ng_dumphooks(void);
91 
92 #endif    /* NETGRAPH_DEBUG */
93 /*
94  * DEAD versions of the structures.
95  * In order to avoid races, it is sometimes necessary to point
96  * at SOMETHING even though theoretically, the current entity is
97  * INVALID. Use these to avoid these races.
98  */
99 struct ng_type ng_deadtype = {
100           NG_ABI_VERSION,
101           "dead",
102           NULL,     /* modevent */
103           NULL,     /* constructor */
104           NULL,     /* rcvmsg */
105           NULL,     /* shutdown */
106           NULL,     /* newhook */
107           NULL,     /* findhook */
108           NULL,     /* connect */
109           NULL,     /* rcvdata */
110           NULL,     /* disconnect */
111           NULL,     /* cmdlist */
112 };
113 
114 struct ng_node ng_deadnode = {
115           "dead",
116           &ng_deadtype,
117           NGF_INVALID,
118           0,        /* numhooks */
119           NULL,     /* private */
120           0,        /* ID */
121           LIST_HEAD_INITIALIZER(ng_deadnode.hooks),
122           {},       /* all_nodes list entry */
123           {},       /* id hashtable list entry */
124           {
125                     0,
126                     NULL,
127                     0,
128                     NULL,
129           },        /* token */
130           1,        /* refs */
131 #ifdef    NETGRAPH_DEBUG
132           ND_MAGIC,
133           __FILE__,
134           __LINE__,
135           {NULL}
136 #endif    /* NETGRAPH_DEBUG */
137 };
138 
139 struct ng_hook ng_deadhook = {
140           "dead",
141           NULL,               /* private */
142           HK_INVALID | HK_DEAD,
143           0,                  /* undefined data link type */
144           &ng_deadhook,       /* Peer is self */
145           &ng_deadnode,       /* attached to deadnode */
146           {},                 /* hooks list */
147           NULL,               /* override rcvmsg() */
148           NULL,               /* override rcvdata() */
149           1,                  /* refs always >= 1 */
150 #ifdef    NETGRAPH_DEBUG
151           HK_MAGIC,
152           __FILE__,
153           __LINE__,
154           {NULL}
155 #endif    /* NETGRAPH_DEBUG */
156 };
157 
158 /*
159  * END DEAD STRUCTURES
160  */
161 
162 /* We don't want our messages to be replied. This is our panic reply port. */
163 static struct lwkt_port ng_panic_reply_port;
164 
165 /* Array of per-CPU target ports */
166 struct lwkt_port *ng_msgport[MAXCPU];
167 
168 /* List of installed types */
169 static LIST_HEAD(, ng_type) ng_typelist;
170 static struct lwkt_token      ng_typelist_token;
171 #define   TYPELIST_RLOCK()    lwkt_gettoken_shared(&ng_typelist_token)
172 #define   TYPELIST_RUNLOCK()  lwkt_reltoken(&ng_typelist_token)
173 #define   TYPELIST_WLOCK()    lwkt_gettoken(&ng_typelist_token)
174 #define   TYPELIST_WUNLOCK()  lwkt_reltoken(&ng_typelist_token)
175 
176 /* Hash related definitions */
177 LIST_HEAD(nodehash, ng_node);
178 static struct nodehash                  *ng_ID_hash;
179 static u_long                            ng_ID_hmask;
180 static u_long                            ng_nodes;
181 static struct nodehash                  *ng_name_hash;
182 static u_long                            ng_name_hmask;
183 static u_long                            ng_named_nodes;
184 static struct lwkt_token       ng_idhash_token;
185 #define   IDHASH_RLOCK()                lwkt_gettoken_shared(&ng_idhash_token)
186 #define   IDHASH_RUNLOCK()    lwkt_reltoken(&ng_idhash_token)
187 #define   IDHASH_WLOCK()                lwkt_gettoken(&ng_idhash_token)
188 #define   IDHASH_WUNLOCK()    lwkt_reltoken(&ng_idhash_token)
189 #define   IDHASH_ASSERT_LOCKED()        KKASSERT(LWKT_TOKEN_HELD_ANY(&ng_idhash_token));
190 /* Method to find a node.. used twice so do it here */
191 #define NG_IDHASH_FN(ID) ((ID) % (ng_ID_hmask + 1))
192 #define NG_IDHASH_FIND(ID, node)                                                \
193           do {                                                                            \
194                     IDHASH_ASSERT_LOCKED();                                               \
195                     LIST_FOREACH(node, &ng_ID_hash[NG_IDHASH_FN(ID)], \
196                                                             nd_idnodes) {                 \
197                               if (NG_NODE_IS_VALID(node)                        \
198                               && (NG_NODE_ID(node) == ID)) {                              \
199                                         break;                                            \
200                               }                                                           \
201                     }                                                                     \
202           } while (0)
203 
204 static struct lwkt_token                ng_namehash_token;
205 #define   NAMEHASH_RLOCK()              lwkt_gettoken_shared(&ng_namehash_token)
206 #define   NAMEHASH_RUNLOCK()            lwkt_reltoken(&ng_namehash_token)
207 #define   NAMEHASH_WLOCK()              lwkt_gettoken(&ng_namehash_token)
208 #define   NAMEHASH_WUNLOCK()            lwkt_reltoken(&ng_namehash_token)
209 #define   NAMEHASH_ASSERT_LOCKED()      KKASSERT(LWKT_TOKEN_HELD_ANY(&ng_namehash_token));
210 
211 /* Internal functions */
212 static int          ng_add_hook(node_p node, const char *name, hook_p * hookp);
213 static int          ng_generic_msg(node_p here, item_p item, hook_p lasthook);
214 static ng_ID_t      ng_decodeidname(const char *name);
215 static int          ngb_mod_event(module_t mod, int event, void *data);
216 static void         ngthread(void *dummy);
217 static int          ng_apply_item(item_p item);
218 static node_p       ng_ID2noderef(ng_ID_t ID);
219 static int          ng_con_nodes(item_p item, node_p node, const char *name,
220                         node_p node2, const char *name2);
221 static int          ng_con_part2(node_p node, item_p item, hook_p hook);
222 static int          ng_con_part3(node_p node, item_p item, hook_p hook);
223 static int          ng_mkpeer(node_p node, const char *name, const char *name2,
224                         char *type);
225 static void         ng_name_rehash(void);
226 static void         ng_ID_rehash(void);
227 static boolean_t    bzero_ctor(void *obj, void *private, int ocflags);
228 
229 /* Imported, these used to be externally visible, some may go back. */
230 void      ng_destroy_hook(hook_p hook);
231 node_p    ng_name2noderef(node_p node, const char *name);
232 int       ng_path2noderef(node_p here, const char *path,
233           node_p *dest, hook_p *lasthook);
234 int       ng_make_node(const char *type, node_p *nodepp);
235 int       ng_path_parse(char *addr, char **node, char **path, char **hook);
236 void      ng_rmnode(node_p node, hook_p dummy1, void *dummy2, int dummy3);
237 void      ng_unname(node_p node);
238 
239 
240 /* Our own netgraph malloc type */
241 MALLOC_DEFINE(M_NETGRAPH, "netgraph", "netgraph structures and ctrl messages");
242 MALLOC_DEFINE(M_NETGRAPH_HOOK, "netgraph_hook", "netgraph hook structures");
243 MALLOC_DEFINE(M_NETGRAPH_NODE, "netgraph_node", "netgraph node structures");
244 MALLOC_DEFINE(M_NETGRAPH_MSG, "netgraph_msg", "netgraph name storage");
245 MALLOC_DEFINE(M_NETGRAPH_APPLY, "netgraph_apply", "netgraph apply_info structures");
246 
247 /* Should not be visible outside this file */
248 
249 #define _NG_ALLOC_HOOK(hook) \
250           hook = kmalloc(sizeof(*hook), M_NETGRAPH_HOOK, \
251               M_WAITOK | M_NULLOK | M_ZERO)
252 #define _NG_ALLOC_NODE(node) \
253           node = kmalloc(sizeof(*node), M_NETGRAPH_NODE, \
254               M_WAITOK | M_NULLOK | M_ZERO)
255 
256 #ifdef NETGRAPH_DEBUG /*----------------------------------------------*/
257 /*
258  * In debug mode:
259  * In an attempt to help track reference count screwups
260  * we do not free objects back to the malloc system, but keep them
261  * in a local cache where we can examine them and keep information safely
262  * after they have been freed.
263  * We use this scheme for nodes and hooks, and to some extent for items.
264  */
265 static __inline hook_p
ng_alloc_hook(void)266 ng_alloc_hook(void)
267 {
268           hook_p hook;
269           SLIST_ENTRY(ng_hook) temp;
270           mtx_lock(&ng_nodelist_mtx);
271           hook = LIST_FIRST(&ng_freehooks);
272           if (hook) {
273                     LIST_REMOVE(hook, hk_hooks);
274                     bcopy(&hook->hk_all, &temp, sizeof(temp));
275                     bzero(hook, sizeof(struct ng_hook));
276                     bcopy(&temp, &hook->hk_all, sizeof(temp));
277                     mtx_unlock(&ng_nodelist_mtx);
278                     hook->hk_magic = HK_MAGIC;
279           } else {
280                     mtx_unlock(&ng_nodelist_mtx);
281                     _NG_ALLOC_HOOK(hook);
282                     if (hook) {
283                               hook->hk_magic = HK_MAGIC;
284                               mtx_lock(&ng_nodelist_mtx);
285                               SLIST_INSERT_HEAD(&ng_allhooks, hook, hk_all);
286                               mtx_unlock(&ng_nodelist_mtx);
287                     }
288           }
289           return (hook);
290 }
291 
292 static __inline node_p
ng_alloc_node(void)293 ng_alloc_node(void)
294 {
295           node_p node;
296           SLIST_ENTRY(ng_node) temp;
297           mtx_lock(&ng_nodelist_mtx);
298           node = LIST_FIRST(&ng_freenodes);
299           if (node) {
300                     LIST_REMOVE(node, nd_nodes);
301                     bcopy(&node->nd_all, &temp, sizeof(temp));
302                     bzero(node, sizeof(struct ng_node));
303                     bcopy(&temp, &node->nd_all, sizeof(temp));
304                     mtx_unlock(&ng_nodelist_mtx);
305                     node->nd_magic = ND_MAGIC;
306           } else {
307                     mtx_unlock(&ng_nodelist_mtx);
308                     _NG_ALLOC_NODE(node);
309                     if (node) {
310                               node->nd_magic = ND_MAGIC;
311                               mtx_lock(&ng_nodelist_mtx);
312                               SLIST_INSERT_HEAD(&ng_allnodes, node, nd_all);
313                               mtx_unlock(&ng_nodelist_mtx);
314                     }
315           }
316           return (node);
317 }
318 
319 #define NG_ALLOC_HOOK(hook) do { (hook) = ng_alloc_hook(); } while (0)
320 #define NG_ALLOC_NODE(node) do { (node) = ng_alloc_node(); } while (0)
321 
322 
323 #define NG_FREE_HOOK(hook)                                                      \
324           do {                                                                            \
325                     mtx_lock(&ng_nodelist_mtx);                       \
326                     LIST_INSERT_HEAD(&ng_freehooks, hook, hk_hooks);  \
327                     hook->hk_magic = 0;                                         \
328                     mtx_unlock(&ng_nodelist_mtx);                     \
329           } while (0)
330 
331 #define NG_FREE_NODE(node)                                                      \
332           do {                                                                            \
333                     mtx_lock(&ng_nodelist_mtx);                       \
334                     LIST_INSERT_HEAD(&ng_freenodes, node, nd_nodes);  \
335                     node->nd_magic = 0;                                         \
336                     mtx_unlock(&ng_nodelist_mtx);                     \
337           } while (0)
338 
339 #else /* NETGRAPH_DEBUG */ /*----------------------------------------------*/
340 
341 #define NG_ALLOC_HOOK(hook) _NG_ALLOC_HOOK(hook)
342 #define NG_ALLOC_NODE(node) _NG_ALLOC_NODE(node)
343 
344 #define NG_FREE_HOOK(hook) do { kfree((hook), M_NETGRAPH_HOOK); } while (0)
345 #define NG_FREE_NODE(node) do { kfree((node), M_NETGRAPH_NODE); } while (0)
346 
347 #endif /* NETGRAPH_DEBUG */ /*----------------------------------------------*/
348 
349 /* Set this to kdb_enter("X") to catch all errors as they occur */
350 #ifndef TRAP_ERROR
351 #define TRAP_ERROR()
352 #endif
353 
354 static    ng_ID_t nextID = 1;
355 
356 #ifdef INVARIANTS
357 #define CHECK_DATA_MBUF(m)    do {                                              \
358                     struct mbuf *n;                                                       \
359                     int total;                                                            \
360                                                                                           \
361                     M_ASSERTPKTHDR(m);                                          \
362                     for (total = 0, n = (m); n != NULL; n = n->m_next) {        \
363                               total += n->m_len;                                \
364                               if (n->m_nextpkt != NULL)                         \
365                                         panic("%s: m_nextpkt", __func__);       \
366                     }                                                                     \
367                                                                                           \
368                     if ((m)->m_pkthdr.len != total) {                           \
369                               panic("%s: %d != %d",                                       \
370                                   __func__, (m)->m_pkthdr.len, total);          \
371                     }                                                                     \
372           } while (0)
373 #else
374 #define CHECK_DATA_MBUF(m)
375 #endif
376 
377 #define ERROUT(x)   do { error = (x); goto done; } while (0)
378 
379 /************************************************************************
380           Parse type definitions for generic messages
381 ************************************************************************/
382 
383 /* Handy structure parse type defining macro */
384 #define DEFINE_PARSE_STRUCT_TYPE(lo, up, args)                                  \
385 static const struct ng_parse_struct_field                                       \
386           ng_ ## lo ## _type_fields[] = NG_GENERIC_ ## up ## _INFO args;        \
387 static const struct ng_parse_type ng_generic_ ## lo ## _type = {      \
388           &ng_parse_struct_type,                                                          \
389           &ng_ ## lo ## _type_fields                                            \
390 }
391 
392 DEFINE_PARSE_STRUCT_TYPE(mkpeer, MKPEER, ());
393 DEFINE_PARSE_STRUCT_TYPE(connect, CONNECT, ());
394 DEFINE_PARSE_STRUCT_TYPE(name, NAME, ());
395 DEFINE_PARSE_STRUCT_TYPE(rmhook, RMHOOK, ());
396 DEFINE_PARSE_STRUCT_TYPE(nodeinfo, NODEINFO, ());
397 DEFINE_PARSE_STRUCT_TYPE(typeinfo, TYPEINFO, ());
398 DEFINE_PARSE_STRUCT_TYPE(linkinfo, LINKINFO, (&ng_generic_nodeinfo_type));
399 
400 /* Get length of an array when the length is stored as a 32 bit
401    value immediately preceding the array -- as with struct namelist
402    and struct typelist. */
403 static int
ng_generic_list_getLength(const struct ng_parse_type * type,const u_char * start,const u_char * buf)404 ng_generic_list_getLength(const struct ng_parse_type *type,
405           const u_char *start, const u_char *buf)
406 {
407           return *((const u_int32_t *)(buf - 4));
408 }
409 
410 /* Get length of the array of struct linkinfo inside a struct hooklist */
411 static int
ng_generic_linkinfo_getLength(const struct ng_parse_type * type,const u_char * start,const u_char * buf)412 ng_generic_linkinfo_getLength(const struct ng_parse_type *type,
413           const u_char *start, const u_char *buf)
414 {
415           const struct hooklist *hl = (const struct hooklist *)start;
416 
417           return hl->nodeinfo.hooks;
418 }
419 
420 /* Array type for a variable length array of struct namelist */
421 static const struct ng_parse_array_info ng_nodeinfoarray_type_info = {
422           &ng_generic_nodeinfo_type,
423           &ng_generic_list_getLength
424 };
425 static const struct ng_parse_type ng_generic_nodeinfoarray_type = {
426           &ng_parse_array_type,
427           &ng_nodeinfoarray_type_info
428 };
429 
430 #if 0 /* unused */
431 /* Array type for a variable length array of struct typelist */
432 static const struct ng_parse_array_info ng_typeinfoarray_type_info = {
433           &ng_generic_typeinfo_type,
434           &ng_generic_list_getLength
435 };
436 static const struct ng_parse_type ng_generic_typeinfoarray_type = {
437           &ng_parse_array_type,
438           &ng_typeinfoarray_type_info
439 };
440 #endif
441 
442 /* Array type for array of struct linkinfo in struct hooklist */
443 static const struct ng_parse_array_info ng_generic_linkinfo_array_type_info = {
444           &ng_generic_linkinfo_type,
445           &ng_generic_linkinfo_getLength
446 };
447 static const struct ng_parse_type ng_generic_linkinfo_array_type = {
448           &ng_parse_array_type,
449           &ng_generic_linkinfo_array_type_info
450 };
451 
452 #if 0 /* unused */
453 DEFINE_PARSE_STRUCT_TYPE(typelist, TYPELIST, (&ng_generic_typeinfoarray_type));
454 #endif
455 DEFINE_PARSE_STRUCT_TYPE(hooklist, HOOKLIST,
456           (&ng_generic_nodeinfo_type, &ng_generic_linkinfo_array_type));
457 DEFINE_PARSE_STRUCT_TYPE(listnodes, LISTNODES,
458           (&ng_generic_nodeinfoarray_type));
459 
460 /* List of commands and how to convert arguments to/from ASCII */
461 static const struct ng_cmdlist ng_generic_cmds[] = {
462           {
463             NGM_GENERIC_COOKIE,
464             NGM_SHUTDOWN,
465             "shutdown",
466             NULL,
467             NULL
468           },
469           {
470             NGM_GENERIC_COOKIE,
471             NGM_MKPEER,
472             "mkpeer",
473             &ng_generic_mkpeer_type,
474             NULL
475           },
476           {
477             NGM_GENERIC_COOKIE,
478             NGM_CONNECT,
479             "connect",
480             &ng_generic_connect_type,
481             NULL
482           },
483           {
484             NGM_GENERIC_COOKIE,
485             NGM_NAME,
486             "name",
487             &ng_generic_name_type,
488             NULL
489           },
490           {
491             NGM_GENERIC_COOKIE,
492             NGM_RMHOOK,
493             "rmhook",
494             &ng_generic_rmhook_type,
495             NULL
496           },
497           {
498             NGM_GENERIC_COOKIE,
499             NGM_NODEINFO,
500             "nodeinfo",
501             NULL,
502             &ng_generic_nodeinfo_type
503           },
504           {
505             NGM_GENERIC_COOKIE,
506             NGM_LISTHOOKS,
507             "listhooks",
508             NULL,
509             &ng_generic_hooklist_type
510           },
511           {
512             NGM_GENERIC_COOKIE,
513             NGM_LISTNAMES,
514             "listnames",
515             NULL,
516             &ng_generic_listnodes_type  /* same as NGM_LISTNODES */
517           },
518           {
519             NGM_GENERIC_COOKIE,
520             NGM_LISTNODES,
521             "listnodes",
522             NULL,
523             &ng_generic_listnodes_type
524           },
525           {
526             NGM_GENERIC_COOKIE,
527             NGM_LISTTYPES,
528             "listtypes",
529             NULL,
530             &ng_generic_typeinfo_type
531           },
532           {
533             NGM_GENERIC_COOKIE,
534             NGM_TEXT_CONFIG,
535             "textconfig",
536             NULL,
537             &ng_parse_string_type
538           },
539           {
540             NGM_GENERIC_COOKIE,
541             NGM_TEXT_STATUS,
542             "textstatus",
543             NULL,
544             &ng_parse_string_type
545           },
546           {
547             NGM_GENERIC_COOKIE,
548             NGM_ASCII2BINARY,
549             "ascii2binary",
550             &ng_parse_ng_mesg_type,
551             &ng_parse_ng_mesg_type
552           },
553           {
554             NGM_GENERIC_COOKIE,
555             NGM_BINARY2ASCII,
556             "binary2ascii",
557             &ng_parse_ng_mesg_type,
558             &ng_parse_ng_mesg_type
559           },
560           { 0 }
561 };
562 
563 /************************************************************************
564                               Node routines
565 ************************************************************************/
566 
567 /*
568  * Instantiate a node of the requested type
569  */
570 int
ng_make_node(const char * typename,node_p * nodepp)571 ng_make_node(const char *typename, node_p *nodepp)
572 {
573           struct ng_type *type;
574           int       error;
575 
576           /* Check that the type makes sense */
577           if (typename == NULL) {
578                     TRAP_ERROR();
579                     return (EINVAL);
580           }
581 
582           /* Locate the node type. If we fail we return. Do not try to load
583            * module.
584            */
585           if ((type = ng_findtype(typename)) == NULL)
586                     return (ENXIO);
587 
588           /*
589            * If we have a constructor, then make the node and
590            * call the constructor to do type specific initialisation.
591            */
592           if (type->constructor != NULL) {
593                     if ((error = ng_make_node_common(type, nodepp)) == 0) {
594                               if ((error = ((*type->constructor)(*nodepp))) != 0) {
595                                         NG_NODE_UNREF(*nodepp);
596                               }
597                     }
598           } else {
599                     /*
600                      * Node has no constructor. We cannot ask for one
601                      * to be made. It must be brought into existence by
602                      * some external agency. The external agency should
603                      * call ng_make_node_common() directly to get the
604                      * netgraph part initialised.
605                      */
606                     TRAP_ERROR();
607                     error = EINVAL;
608           }
609           return (error);
610 }
611 
612 /*
613  * Generic node creation. Called by node initialisation for externally
614  * instantiated nodes (e.g. hardware, sockets, etc ).
615  * The returned node has a reference count of 1.
616  */
617 int
ng_make_node_common(struct ng_type * type,node_p * nodepp)618 ng_make_node_common(struct ng_type *type, node_p *nodepp)
619 {
620           node_p node;
621 
622           /* Require the node type to have been already installed */
623           if (ng_findtype(type->name) == NULL) {
624                     TRAP_ERROR();
625                     return (EINVAL);
626           }
627 
628           /* Make a node and try attach it to the type */
629           NG_ALLOC_NODE(node);
630           if (node == NULL) {
631                     TRAP_ERROR();
632                     return (ENOMEM);
633           }
634           node->nd_type = type;
635           NG_NODE_REF(node);                                /* note reference */
636           type->refs++;
637 
638           /* Initialize the reader/writer shared token */
639           lwkt_token_init(&node->nd_token, type->name);
640 
641           /* Initialize hook list for new node */
642           LIST_INIT(&node->nd_hooks);
643 
644           /* Get an ID and put us in the hash chain. */
645           IDHASH_WLOCK();
646           for (;;) { /* wrap protection, even if silly */
647                     node_p node2 = NULL;
648                     node->nd_ID = nextID++; /* 137/second for 1 year before wrap */
649 
650                     /* Is there a problem with the new number? */
651                     NG_IDHASH_FIND(node->nd_ID, node2); /* already taken? */
652                     if ((node->nd_ID != 0) && (node2 == NULL)) {
653                               break;
654                     }
655           }
656           ng_nodes++;
657           if (ng_nodes * 2 > ng_ID_hmask)
658                     ng_ID_rehash();
659           LIST_INSERT_HEAD(&ng_ID_hash[NG_IDHASH_FN(node->nd_ID)], node,
660               nd_idnodes);
661           IDHASH_WUNLOCK();
662 
663           /* Done */
664           *nodepp = node;
665           return (0);
666 }
667 
668 /*
669  * Forceably start the shutdown process on a node. Either call
670  * its shutdown method, or do the default shutdown if there is
671  * no type-specific method.
672  *
673  * We can only be called from a shutdown message, so we know we have
674  * a writer lock, and therefore exclusive access.
675  *
676  * Persistent node types must have a type-specific method which
677  * allocates a new node in which case, this one is irretrievably going away,
678  * or cleans up anything it needs, and just makes the node valid again,
679  * in which case we allow the node to survive.
680  *
681  * XXX We need to think of how to tell a persistent node that we
682  * REALLY need to go away because the hardware has gone or we
683  * are rebooting.... etc.
684  */
685 void
ng_rmnode(node_p node,hook_p dummy1,void * dummy2,int dummy3)686 ng_rmnode(node_p node, hook_p dummy1, void *dummy2, int dummy3)
687 {
688           hook_p hook;
689 
690           /* Check if it's already shutting down */
691           if ((node->nd_flags & NGF_CLOSING) != 0)
692                     return;
693 
694           if (node == &ng_deadnode) {
695                     kprintf ("shutdown called on deadnode\n");
696                     return;
697           }
698 
699           /* Add an extra reference so it doesn't go away during this */
700           NG_NODE_REF(node);
701 
702           /*
703            * Mark it invalid so any newcomers know not to try use it
704            * Also add our own mark so we can't recurse
705            * note that NGF_INVALID does not do this as it's also set during
706            * creation
707            */
708           node->nd_flags |= NGF_INVALID|NGF_CLOSING;
709 
710           /* If node has its pre-shutdown method, then call it first*/
711           if (node->nd_type && node->nd_type->close)
712                     (*node->nd_type->close)(node);
713 
714           /* Notify all remaining connected nodes to disconnect */
715           while ((hook = LIST_FIRST(&node->nd_hooks)) != NULL)
716                     ng_destroy_hook(hook);
717 
718           /* Ask the type if it has anything to do in this case */
719           if (node->nd_type && node->nd_type->shutdown) {
720                     (*node->nd_type->shutdown)(node);
721                     if (NG_NODE_IS_VALID(node)) {
722                               /*
723                                * Well, blow me down if the node code hasn't declared
724                                * that it doesn't want to die.
725                                * Presumably it is a persistant node.
726                                * If we REALLY want it to go away,
727                                *  e.g. hardware going away,
728                                * Our caller should set NGF_REALLY_DIE in nd_flags.
729                                */
730                               node->nd_flags &= ~(NGF_INVALID|NGF_CLOSING);
731                               NG_NODE_UNREF(node); /* Assume they still have theirs */
732                               return;
733                     }
734           } else {                                /* do the default thing */
735                     NG_NODE_UNREF(node);
736           }
737 
738           ng_unname(node); /* basically a NOP these days */
739 
740           /*
741            * Remove extra reference, possibly the last
742            * Possible other holders of references may include
743            * timeout callouts, but theoretically the node's supposed to
744            * have cancelled them. Possibly hardware dependencies may
745            * force a driver to 'linger' with a reference.
746            */
747           NG_NODE_UNREF(node);
748 }
749 
750 /*
751  * Remove a reference to the node, possibly the last.
752  * deadnode always acts as it it were the last.
753  */
754 void
ng_unref_node(node_p node)755 ng_unref_node(node_p node)
756 {
757 
758           if (node == &ng_deadnode)
759                     return;
760 
761           if (refcount_release(&node->nd_refs)) { /* we were the last */
762 
763                     node->nd_type->refs--; /* XXX maybe should get types lock? */
764                     NAMEHASH_WLOCK();
765                     if (NG_NODE_HAS_NAME(node)) {
766                               ng_named_nodes--;
767                               LIST_REMOVE(node, nd_nodes);
768                     }
769                     NAMEHASH_WUNLOCK();
770 
771                     IDHASH_WLOCK();
772                     ng_nodes--;
773                     LIST_REMOVE(node, nd_idnodes);
774                     IDHASH_WUNLOCK();
775 
776                     NG_FREE_NODE(node);
777           }
778 }
779 
780 /************************************************************************
781                               Node ID handling
782 ************************************************************************/
783 static node_p
ng_ID2noderef(ng_ID_t ID)784 ng_ID2noderef(ng_ID_t ID)
785 {
786           node_p node;
787 
788           IDHASH_RLOCK();
789           NG_IDHASH_FIND(ID, node);
790           if (node)
791                     NG_NODE_REF(node);
792           IDHASH_RUNLOCK();
793           return(node);
794 }
795 
796 ng_ID_t
ng_node2ID(node_p node)797 ng_node2ID(node_p node)
798 {
799           return (node ? NG_NODE_ID(node) : 0);
800 }
801 
802 /************************************************************************
803                               Node name handling
804 ************************************************************************/
805 
806 /*
807  * Assign a node a name.
808  */
809 int
ng_name_node(node_p node,const char * name)810 ng_name_node(node_p node, const char *name)
811 {
812           uint32_t hash;
813           node_p node2;
814           int i;
815 
816           /* Check the name is valid */
817           for (i = 0; i < NG_NODESIZ; i++) {
818                     if (name[i] == '\0' || name[i] == '.' || name[i] == ':')
819                               break;
820           }
821           if (i == 0 || name[i] != '\0') {
822                     TRAP_ERROR();
823                     return (EINVAL);
824           }
825           if (ng_decodeidname(name) != 0) { /* valid IDs not allowed here */
826                     TRAP_ERROR();
827                     return (EINVAL);
828           }
829 
830           NAMEHASH_WLOCK();
831           if (ng_named_nodes * 2 > ng_name_hmask)
832                     ng_name_rehash();
833 
834           hash = hash32_str(name, HASHINIT) & ng_name_hmask;
835           /* Check the name isn't already being used. */
836           LIST_FOREACH(node2, &ng_name_hash[hash], nd_nodes)
837                     if (NG_NODE_IS_VALID(node2) &&
838                         (strcmp(NG_NODE_NAME(node2), name) == 0)) {
839                               NAMEHASH_WUNLOCK();
840                               return (EADDRINUSE);
841                     }
842 
843           if (NG_NODE_HAS_NAME(node))
844                     LIST_REMOVE(node, nd_nodes);
845           else
846                     ng_named_nodes++;
847           /* Copy it. */
848           strlcpy(NG_NODE_NAME(node), name, NG_NODESIZ);
849 
850           /* Update name hash. */
851           LIST_INSERT_HEAD(&ng_name_hash[hash], node, nd_nodes);
852           NAMEHASH_WUNLOCK();
853 
854           return (0);
855 }
856 
857 /*
858  * Find a node by absolute name. The name should NOT end with ':'
859  * The name "." means "this node" and "[xxx]" means "the node
860  * with ID (ie, at address) xxx".
861  *
862  * Returns the node if found, else NULL.
863  * Eventually should add something faster than a sequential search.
864  * Note it acquires a reference on the node so you can be sure it's still
865  * there.
866  */
867 node_p
ng_name2noderef(node_p here,const char * name)868 ng_name2noderef(node_p here, const char *name)
869 {
870           node_p node;
871           ng_ID_t temp;
872           int       hash;
873 
874           /* "." means "this node" */
875           if (strcmp(name, ".") == 0) {
876                     NG_NODE_REF(here);
877                     return(here);
878           }
879 
880           /* Check for name-by-ID */
881           if ((temp = ng_decodeidname(name)) != 0) {
882                     return (ng_ID2noderef(temp));
883           }
884 
885           /* Find node by name. */
886           hash = hash32_str(name, HASHINIT) & ng_name_hmask;
887           NAMEHASH_RLOCK();
888           LIST_FOREACH(node, &ng_name_hash[hash], nd_nodes)
889                     if (NG_NODE_IS_VALID(node) &&
890                         (strcmp(NG_NODE_NAME(node), name) == 0)) {
891                               NG_NODE_REF(node);
892                               break;
893                     }
894           NAMEHASH_RUNLOCK();
895 
896           return (node);
897 }
898 
899 /*
900  * Decode an ID name, eg. "[f03034de]". Returns 0 if the
901  * string is not valid, otherwise returns the value.
902  */
903 static ng_ID_t
ng_decodeidname(const char * name)904 ng_decodeidname(const char *name)
905 {
906           const int len = strlen(name);
907           char *eptr;
908           u_long val;
909 
910           /* Check for proper length, brackets, no leading junk */
911           if ((len < 3)
912           || (name[0] != '[')
913           || (name[len - 1] != ']')
914           || (!isxdigit(name[1]))) {
915                     return ((ng_ID_t)0);
916           }
917 
918           /* Decode number */
919           val = strtoul(name + 1, &eptr, 16);
920           if ((eptr - name != len - 1)
921           || (val == ULONG_MAX)
922           || (val == 0)) {
923                     return ((ng_ID_t)0);
924           }
925           return (ng_ID_t)val;
926 }
927 
928 /*
929  * Remove a name from a node. This should only be called
930  * when shutting down and removing the node.
931  */
932 void
ng_unname(node_p node)933 ng_unname(node_p node)
934 {
935 }
936 
937 /*
938  * Allocate a bigger name hash.
939  */
940 static void
ng_name_rehash(void)941 ng_name_rehash(void)
942 {
943           struct nodehash *new;
944           uint32_t hash;
945           u_long hmask;
946           node_p node, node2;
947           int i;
948 
949           NAMEHASH_ASSERT_LOCKED();
950           new = hashinit((ng_name_hmask + 1) * 2, M_NETGRAPH_NODE, &hmask);
951           if (new == NULL)
952                     return;
953 
954           for (i = 0; i <= ng_name_hmask; i++) {
955                     LIST_FOREACH_MUTABLE(node, &ng_name_hash[i], nd_nodes, node2) {
956 #ifdef INVARIANTS
957                               LIST_REMOVE(node, nd_nodes);
958 #endif
959                               hash = hash32_str(NG_NODE_NAME(node), HASHINIT) & hmask;
960                               LIST_INSERT_HEAD(&new[hash], node, nd_nodes);
961                     }
962           }
963 
964           hashdestroy(ng_name_hash, M_NETGRAPH_NODE, ng_name_hmask);
965           ng_name_hash = new;
966           ng_name_hmask = hmask;
967 }
968 
969 /*
970  * Allocate a bigger ID hash.
971  */
972 static void
ng_ID_rehash(void)973 ng_ID_rehash(void)
974 {
975           struct nodehash *new;
976           uint32_t hash;
977           u_long hmask;
978           node_p node, node2;
979           int i;
980 
981           IDHASH_ASSERT_LOCKED();
982           new = hashinit((ng_ID_hmask + 1) * 2, M_NETGRAPH_NODE, &hmask);
983           if (new == NULL)
984                     return;
985 
986           for (i = 0; i <= ng_ID_hmask; i++) {
987                     LIST_FOREACH_MUTABLE(node, &ng_ID_hash[i], nd_idnodes, node2) {
988 #ifdef INVARIANTS
989                               LIST_REMOVE(node, nd_idnodes);
990 #endif
991                               hash = (node->nd_ID % (hmask + 1));
992                               LIST_INSERT_HEAD(&new[hash], node, nd_idnodes);
993                     }
994           }
995 
996           hashdestroy(ng_ID_hash, M_NETGRAPH_NODE, ng_name_hmask);
997           ng_ID_hash = new;
998           ng_ID_hmask = hmask;
999 }
1000 
1001 /************************************************************************
1002                               Hook routines
1003  Names are not optional. Hooks are always connected, except for a
1004  brief moment within these routines. On invalidation or during creation
1005  they are connected to the 'dead' hook.
1006 ************************************************************************/
1007 
1008 /*
1009  * Remove a hook reference
1010  */
1011 void
ng_unref_hook(hook_p hook)1012 ng_unref_hook(hook_p hook)
1013 {
1014           int v;
1015 
1016           if (hook == &ng_deadhook) {
1017                     return;
1018           }
1019 
1020           v = atomic_fetchadd_int(&hook->hk_refs, -1);
1021 
1022           if (v == 1) { /* we were the last */
1023                     if (_NG_HOOK_NODE(hook)) /* it'll probably be ng_deadnode */
1024                               _NG_NODE_UNREF((_NG_HOOK_NODE(hook)));
1025                     NG_FREE_HOOK(hook);
1026           }
1027 }
1028 
1029 /*
1030  * Add an unconnected hook to a node. Only used internally.
1031  * Assumes node is locked. (XXX not yet true )
1032  */
1033 static int
ng_add_hook(node_p node,const char * name,hook_p * hookp)1034 ng_add_hook(node_p node, const char *name, hook_p *hookp)
1035 {
1036           hook_p hook;
1037           int error = 0;
1038 
1039           /* Check that the given name is good */
1040           if (name == NULL) {
1041                     TRAP_ERROR();
1042                     return (EINVAL);
1043           }
1044           if (ng_findhook(node, name) != NULL) {
1045                     TRAP_ERROR();
1046                     return (EEXIST);
1047           }
1048 
1049           /* Allocate the hook and link it up */
1050           NG_ALLOC_HOOK(hook);
1051           if (hook == NULL) {
1052                     TRAP_ERROR();
1053                     return (ENOMEM);
1054           }
1055           hook->hk_refs = 1;            /* add a reference for us to return */
1056           hook->hk_flags = HK_INVALID;
1057           hook->hk_peer = &ng_deadhook; /* start off this way */
1058           hook->hk_node = node;
1059           NG_NODE_REF(node);            /* each hook counts as a reference */
1060 
1061           /* Set hook name */
1062           strlcpy(NG_HOOK_NAME(hook), name, NG_HOOKSIZ);
1063 
1064           /*
1065            * Check if the node type code has something to say about it
1066            * If it fails, the unref of the hook will also unref the node.
1067            */
1068           if (node->nd_type->newhook != NULL) {
1069                     if ((error = (*node->nd_type->newhook)(node, hook, name))) {
1070                               NG_HOOK_UNREF(hook);          /* this frees the hook */
1071                               return (error);
1072                     }
1073           }
1074           /*
1075            * The 'type' agrees so far, so go ahead and link it in.
1076            * We'll ask again later when we actually connect the hooks.
1077            */
1078           LIST_INSERT_HEAD(&node->nd_hooks, hook, hk_hooks);
1079           node->nd_numhooks++;
1080           NG_HOOK_REF(hook);  /* one for the node */
1081 
1082           if (hookp)
1083                     *hookp = hook;
1084           return (0);
1085 }
1086 
1087 /*
1088  * Find a hook
1089  *
1090  * Node types may supply their own optimized routines for finding
1091  * hooks.  If none is supplied, we just do a linear search.
1092  * XXX Possibly we should add a reference to the hook?
1093  */
1094 hook_p
ng_findhook(node_p node,const char * name)1095 ng_findhook(node_p node, const char *name)
1096 {
1097           hook_p hook;
1098 
1099           if (node->nd_type->findhook != NULL)
1100                     return (*node->nd_type->findhook)(node, name);
1101           LIST_FOREACH(hook, &node->nd_hooks, hk_hooks) {
1102                     if (NG_HOOK_IS_VALID(hook)
1103                     && (strcmp(NG_HOOK_NAME(hook), name) == 0))
1104                               return (hook);
1105           }
1106           return (NULL);
1107 }
1108 
1109 /*
1110  * Destroy a hook
1111  *
1112  * As hooks are always attached, this really destroys two hooks.
1113  * The one given, and the one attached to it. Disconnect the hooks
1114  * from each other first. We reconnect the peer hook to the 'dead'
1115  * hook so that it can still exist after we depart. We then
1116  * send the peer its own destroy message. This ensures that we only
1117  * interact with the peer's structures when it is locked processing that
1118  * message. We hold a reference to the peer hook so we are guaranteed that
1119  * the peer hook and node are still going to exist until
1120  * we are finished there as the hook holds a ref on the node.
1121  * We run this same code again on the peer hook, but that time it is already
1122  * attached to the 'dead' hook.
1123  *
1124  * This routine is called at all stages of hook creation
1125  * on error detection and must be able to handle any such stage.
1126  */
1127 void
ng_destroy_hook(hook_p hook)1128 ng_destroy_hook(hook_p hook)
1129 {
1130           hook_p peer;
1131           node_p node;
1132 
1133           if (hook == &ng_deadhook) {   /* better safe than sorry */
1134                     kprintf("ng_destroy_hook called on deadhook\n");
1135                     return;
1136           }
1137 
1138           /*
1139            * Protect divorce process with mutex, to avoid races on
1140            * simultaneous disconnect.
1141            */
1142           TOPOLOGY_WLOCK();
1143 
1144           hook->hk_flags |= HK_INVALID;
1145 
1146           peer = NG_HOOK_PEER(hook);
1147           node = NG_HOOK_NODE(hook);
1148 
1149           if (peer && (peer != &ng_deadhook)) {
1150                     /*
1151                      * Set the peer to point to ng_deadhook
1152                      * from this moment on we are effectively independent it.
1153                      * send it an rmhook message of it's own.
1154                      */
1155                     peer->hk_peer = &ng_deadhook; /* They no longer know us */
1156                     hook->hk_peer = &ng_deadhook; /* Nor us, them */
1157                     if (NG_HOOK_NODE(peer) == &ng_deadnode) {
1158                               /*
1159                                * If it's already divorced from a node,
1160                                * just free it.
1161                                */
1162                               TOPOLOGY_WUNLOCK();
1163                     } else {
1164                               TOPOLOGY_WUNLOCK();
1165                               ng_rmhook_self(peer);         /* Send it a surprise */
1166                     }
1167                     NG_HOOK_UNREF(peer);                    /* account for peer link */
1168                     NG_HOOK_UNREF(hook);                    /* account for peer link */
1169           } else
1170                     TOPOLOGY_WUNLOCK();
1171 
1172           TOPOLOGY_NOTOWNED();
1173 
1174           /*
1175            * Remove the hook from the node's list to avoid possible recursion
1176            * in case the disconnection results in node shutdown.
1177            */
1178           if (node == &ng_deadnode) { /* happens if called from ng_con_nodes() */
1179                     return;
1180           }
1181           LIST_REMOVE(hook, hk_hooks);
1182           node->nd_numhooks--;
1183           if (node->nd_type->disconnect) {
1184                     /*
1185                      * The type handler may elect to destroy the node so don't
1186                      * trust its existence after this point. (except
1187                      * that we still hold a reference on it. (which we
1188                      * inherrited from the hook we are destroying)
1189                      */
1190                     (*node->nd_type->disconnect) (hook);
1191           }
1192 
1193           /*
1194            * Note that because we will point to ng_deadnode, the original node
1195            * is not decremented automatically so we do that manually.
1196            */
1197           _NG_HOOK_NODE(hook) = &ng_deadnode;
1198           NG_NODE_UNREF(node);          /* We no longer point to it so adjust count */
1199           NG_HOOK_UNREF(hook);          /* Account for linkage (in list) to node */
1200 }
1201 
1202 /*
1203  * Take two hooks on a node and merge the connection so that the given node
1204  * is effectively bypassed.
1205  */
1206 int
ng_bypass(hook_p hook1,hook_p hook2)1207 ng_bypass(hook_p hook1, hook_p hook2)
1208 {
1209           if (hook1->hk_node != hook2->hk_node) {
1210                     TRAP_ERROR();
1211                     return (EINVAL);
1212           }
1213           hook1->hk_peer->hk_peer = hook2->hk_peer;
1214           hook2->hk_peer->hk_peer = hook1->hk_peer;
1215 
1216           hook1->hk_peer = &ng_deadhook;
1217           hook2->hk_peer = &ng_deadhook;
1218 
1219           NG_HOOK_UNREF(hook1);
1220           NG_HOOK_UNREF(hook2);
1221 
1222           /* XXX If we ever cache methods on hooks update them as well */
1223           ng_destroy_hook(hook1);
1224           ng_destroy_hook(hook2);
1225           return (0);
1226 }
1227 
1228 /*
1229  * Install a new netgraph type
1230  */
1231 int
ng_newtype(struct ng_type * tp)1232 ng_newtype(struct ng_type *tp)
1233 {
1234           const size_t namelen = strlen(tp->name);
1235 
1236           /* Check version and type name fields */
1237           if ((tp->version != NG_ABI_VERSION)
1238           || (namelen == 0)
1239           || (namelen >= NG_TYPESIZ)) {
1240                     TRAP_ERROR();
1241                     if (tp->version != NG_ABI_VERSION) {
1242                               kprintf("Netgraph: Node type rejected. ABI mismatch. Suggest recompile\n");
1243                     }
1244                     return (EINVAL);
1245           }
1246 
1247           /* Check for name collision */
1248           if (ng_findtype(tp->name) != NULL) {
1249                     TRAP_ERROR();
1250                     return (EEXIST);
1251           }
1252 
1253           /* Link in new type */
1254           TYPELIST_WLOCK();
1255           LIST_INSERT_HEAD(&ng_typelist, tp, types);
1256           tp->refs = 1;       /* first ref is linked list */
1257           TYPELIST_WUNLOCK();
1258           return (0);
1259 }
1260 
1261 /*
1262  * unlink a netgraph type
1263  * If no examples exist
1264  */
1265 int
ng_rmtype(struct ng_type * tp)1266 ng_rmtype(struct ng_type *tp)
1267 {
1268           /* Check for name collision */
1269           if (tp->refs != 1) {
1270                     TRAP_ERROR();
1271                     return (EBUSY);
1272           }
1273 
1274           /* Unlink type */
1275           TYPELIST_WLOCK();
1276           LIST_REMOVE(tp, types);
1277           TYPELIST_WUNLOCK();
1278           return (0);
1279 }
1280 
1281 /*
1282  * Look for a type of the name given
1283  */
1284 struct ng_type *
ng_findtype(const char * typename)1285 ng_findtype(const char *typename)
1286 {
1287           struct ng_type *type;
1288 
1289           TYPELIST_RLOCK();
1290           LIST_FOREACH(type, &ng_typelist, types) {
1291                     if (strcmp(type->name, typename) == 0)
1292                               break;
1293           }
1294           TYPELIST_RUNLOCK();
1295           return (type);
1296 }
1297 
1298 /************************************************************************
1299                               Composite routines
1300 ************************************************************************/
1301 /*
1302  * Connect two nodes using the specified hooks, using queued functions.
1303  */
1304 static int
ng_con_part3(node_p node,item_p item,hook_p hook)1305 ng_con_part3(node_p node, item_p item, hook_p hook)
1306 {
1307           int       error = 0;
1308 
1309           /*
1310            * When we run, we know that the node 'node' is locked for us.
1311            * Our caller has a reference on the hook.
1312            * Our caller has a reference on the node.
1313            * (In this case our caller is ng_apply_item() ).
1314            * The peer hook has a reference on the hook.
1315            * We are all set up except for the final call to the node, and
1316            * the clearing of the INVALID flag.
1317            */
1318           if (NG_HOOK_NODE(hook) == &ng_deadnode) {
1319                     /*
1320                      * The node must have been freed again since we last visited
1321                      * here. ng_destry_hook() has this effect but nothing else does.
1322                      * We should just release our references and
1323                      * free anything we can think of.
1324                      * Since we know it's been destroyed, and it's our caller
1325                      * that holds the references, just return.
1326                      */
1327                     ERROUT(ENOENT);
1328           }
1329           if (hook->hk_node->nd_type->connect) {
1330                     if ((error = (*hook->hk_node->nd_type->connect) (hook))) {
1331                               ng_destroy_hook(hook);        /* also zaps peer */
1332                               kprintf("failed in ng_con_part3()\n");
1333                               ERROUT(error);
1334                     }
1335           }
1336           /*
1337            *  XXX this is wrong for SMP. Possibly we need
1338            * to separate out 'create' and 'invalid' flags.
1339            * should only set flags on hooks we have locked under our node.
1340            */
1341           hook->hk_flags &= ~HK_INVALID;
1342 done:
1343           NG_FREE_ITEM(item);
1344           return (error);
1345 }
1346 
1347 static int
ng_con_part2(node_p node,item_p item,hook_p hook)1348 ng_con_part2(node_p node, item_p item, hook_p hook)
1349 {
1350           hook_p    peer;
1351           int       error = 0;
1352 
1353           /*
1354            * When we run, we know that the node 'node' is locked for us.
1355            * Our caller has a reference on the hook.
1356            * Our caller has a reference on the node.
1357            * (In this case our caller is ng_apply_item() ).
1358            * The peer hook has a reference on the hook.
1359            * our node pointer points to the 'dead' node.
1360            * First check the hook name is unique.
1361            * Should not happen because we checked before queueing this.
1362            */
1363           if (ng_findhook(node, NG_HOOK_NAME(hook)) != NULL) {
1364                     TRAP_ERROR();
1365                     ng_destroy_hook(hook); /* should destroy peer too */
1366                     kprintf("failed in ng_con_part2()\n");
1367                     ERROUT(EEXIST);
1368           }
1369           /*
1370            * Check if the node type code has something to say about it
1371            * If it fails, the unref of the hook will also unref the attached node,
1372            * however since that node is 'ng_deadnode' this will do nothing.
1373            * The peer hook will also be destroyed.
1374            */
1375           if (node->nd_type->newhook != NULL) {
1376                     if ((error = (*node->nd_type->newhook)(node, hook,
1377                         hook->hk_name))) {
1378                               ng_destroy_hook(hook); /* should destroy peer too */
1379                               kprintf("failed in ng_con_part2()\n");
1380                               ERROUT(error);
1381                     }
1382           }
1383 
1384           /*
1385            * The 'type' agrees so far, so go ahead and link it in.
1386            * We'll ask again later when we actually connect the hooks.
1387            */
1388           hook->hk_node = node;                   /* just overwrite ng_deadnode */
1389           NG_NODE_REF(node);            /* each hook counts as a reference */
1390           LIST_INSERT_HEAD(&node->nd_hooks, hook, hk_hooks);
1391           node->nd_numhooks++;
1392           NG_HOOK_REF(hook);  /* one for the node */
1393 
1394           /*
1395            * We now have a symmetrical situation, where both hooks have been
1396            * linked to their nodes, the newhook methods have been called
1397            * And the references are all correct. The hooks are still marked
1398            * as invalid, as we have not called the 'connect' methods
1399            * yet.
1400            * We can call the local one immediately as we have the
1401            * node locked, but we need to queue the remote one.
1402            */
1403           if (hook->hk_node->nd_type->connect) {
1404                     if ((error = (*hook->hk_node->nd_type->connect) (hook))) {
1405                               ng_destroy_hook(hook);        /* also zaps peer */
1406                               kprintf("failed in ng_con_part2(A)\n");
1407                               ERROUT(error);
1408                     }
1409           }
1410 
1411           /*
1412            * Acquire topo token to avoid race with ng_destroy_hook().
1413            */
1414           TOPOLOGY_RLOCK();
1415           peer = hook->hk_peer;
1416           if (peer == &ng_deadhook) {
1417                     TOPOLOGY_RUNLOCK();
1418                     kprintf("failed in ng_con_part2(B)\n");
1419                     ng_destroy_hook(hook);
1420                     ERROUT(ENOENT);
1421           }
1422           TOPOLOGY_RUNLOCK();
1423 
1424           if ((error = ng_send_fn2(peer->hk_node, peer, item, &ng_con_part3,
1425               NULL, 0, NG_REUSE_ITEM))) {
1426                     kprintf("failed in ng_con_part2(C)\n");
1427                     ng_destroy_hook(hook);        /* also zaps peer */
1428                     return (error);               /* item was consumed. */
1429           }
1430           hook->hk_flags &= ~HK_INVALID; /* need both to be able to work */
1431           return (0);                             /* item was consumed. */
1432 done:
1433           NG_FREE_ITEM(item);
1434           return (error);
1435 }
1436 
1437 /*
1438  * Connect this node with another node. We assume that this node is
1439  * currently locked, as we are only called from an NGM_CONNECT message.
1440  */
1441 static int
ng_con_nodes(item_p item,node_p node,const char * name,node_p node2,const char * name2)1442 ng_con_nodes(item_p item, node_p node, const char *name,
1443     node_p node2, const char *name2)
1444 {
1445           int       error;
1446           hook_p    hook;
1447           hook_p    hook2;
1448 
1449           if (ng_findhook(node2, name2) != NULL) {
1450                     return(EEXIST);
1451           }
1452           if ((error = ng_add_hook(node, name, &hook)))  /* gives us a ref */
1453                     return (error);
1454           /* Allocate the other hook and link it up */
1455           NG_ALLOC_HOOK(hook2);
1456           if (hook2 == NULL) {
1457                     TRAP_ERROR();
1458                     ng_destroy_hook(hook);        /* XXX check ref counts so far */
1459                     NG_HOOK_UNREF(hook);          /* including our ref */
1460                     return (ENOMEM);
1461           }
1462           hook2->hk_refs = 1;           /* start with a reference for us. */
1463           hook2->hk_flags = HK_INVALID;
1464           hook2->hk_peer = hook;                  /* Link the two together */
1465           hook->hk_peer = hook2;
1466           NG_HOOK_REF(hook);            /* Add a ref for the peer to each*/
1467           NG_HOOK_REF(hook2);
1468           hook2->hk_node = &ng_deadnode;
1469           strlcpy(NG_HOOK_NAME(hook2), name2, NG_HOOKSIZ);
1470 
1471           /*
1472            * Queue the function above.
1473            * Procesing continues in that function in the lock context of
1474            * the other node.
1475            */
1476           if ((error = ng_send_fn2(node2, hook2, item, &ng_con_part2, NULL, 0,
1477               NG_NOFLAGS))) {
1478                     kprintf("failed in ng_con_nodes(): %d\n", error);
1479                     ng_destroy_hook(hook);        /* also zaps peer */
1480           }
1481 
1482           NG_HOOK_UNREF(hook);                    /* Let each hook go if it wants to */
1483           NG_HOOK_UNREF(hook2);
1484           return (error);
1485 }
1486 
1487 /*
1488  * Make a peer and connect.
1489  * We assume that the local node is locked.
1490  * The new node probably doesn't need a lock until
1491  * it has a hook, because it cannot really have any work until then,
1492  * but we should think about it a bit more.
1493  *
1494  * The problem may come if the other node also fires up
1495  * some hardware or a timer or some other source of activation,
1496  * also it may already get a command msg via it's ID.
1497  *
1498  * We could use the same method as ng_con_nodes() but we'd have
1499  * to add ability to remove the node when failing. (Not hard, just
1500  * make arg1 point to the node to remove).
1501  * Unless of course we just ignore failure to connect and leave
1502  * an unconnected node?
1503  */
1504 static int
ng_mkpeer(node_p node,const char * name,const char * name2,char * type)1505 ng_mkpeer(node_p node, const char *name, const char *name2, char *type)
1506 {
1507           node_p    node2;
1508           hook_p    hook1, hook2;
1509           int       error;
1510 
1511           if ((error = ng_make_node(type, &node2))) {
1512                     return (error);
1513           }
1514 
1515           if ((error = ng_add_hook(node, name, &hook1))) { /* gives us a ref */
1516                     ng_rmnode(node2, NULL, NULL, 0);
1517                     return (error);
1518           }
1519 
1520           if ((error = ng_add_hook(node2, name2, &hook2))) {
1521                     ng_rmnode(node2, NULL, NULL, 0);
1522                     ng_destroy_hook(hook1);
1523                     NG_HOOK_UNREF(hook1);
1524                     return (error);
1525           }
1526 
1527           /*
1528            * Actually link the two hooks together.
1529            */
1530           hook1->hk_peer = hook2;
1531           hook2->hk_peer = hook1;
1532 
1533           /* Each hook is referenced by the other */
1534           NG_HOOK_REF(hook1);
1535           NG_HOOK_REF(hook2);
1536 
1537           /* Give each node the opportunity to veto the pending connection */
1538           if (hook1->hk_node->nd_type->connect) {
1539                     error = (*hook1->hk_node->nd_type->connect) (hook1);
1540           }
1541 
1542           if ((error == 0) && hook2->hk_node->nd_type->connect) {
1543                     error = (*hook2->hk_node->nd_type->connect) (hook2);
1544 
1545           }
1546 
1547           /*
1548            * drop the references we were holding on the two hooks.
1549            */
1550           if (error) {
1551                     ng_destroy_hook(hook2);       /* also zaps hook1 */
1552                     ng_rmnode(node2, NULL, NULL, 0);
1553           } else {
1554                     /* As a last act, allow the hooks to be used */
1555                     hook1->hk_flags &= ~HK_INVALID;
1556                     hook2->hk_flags &= ~HK_INVALID;
1557           }
1558           NG_HOOK_UNREF(hook1);
1559           NG_HOOK_UNREF(hook2);
1560           return (error);
1561 }
1562 
1563 /************************************************************************
1564                     Utility routines to send self messages
1565 ************************************************************************/
1566 
1567 /* Shut this node down as soon as everyone is clear of it */
1568 /* Should add arg "immediately" to jump the queue */
1569 int
ng_rmnode_self(node_p node)1570 ng_rmnode_self(node_p node)
1571 {
1572           int                 error;
1573 
1574           if (node == &ng_deadnode)
1575                     return (0);
1576           node->nd_flags |= NGF_INVALID;
1577           if (node->nd_flags & NGF_CLOSING)
1578                     return (0);
1579 
1580           error = ng_send_fn(node, NULL, &ng_rmnode, NULL, 0);
1581           return (error);
1582 }
1583 
1584 static void
ng_rmhook_part2(node_p node,hook_p hook,void * arg1,int arg2)1585 ng_rmhook_part2(node_p node, hook_p hook, void *arg1, int arg2)
1586 {
1587           ng_destroy_hook(hook);
1588           return ;
1589 }
1590 
1591 int
ng_rmhook_self(hook_p hook)1592 ng_rmhook_self(hook_p hook)
1593 {
1594           int                 error;
1595           node_p node = NG_HOOK_NODE(hook);
1596 
1597           if (node == &ng_deadnode)
1598                     return (0);
1599 
1600           error = ng_send_fn(node, hook, &ng_rmhook_part2, NULL, 0);
1601           return (error);
1602 }
1603 
1604 /***********************************************************************
1605  * Parse and verify a string of the form:  <NODE:><PATH>
1606  *
1607  * Such a string can refer to a specific node or a specific hook
1608  * on a specific node, depending on how you look at it. In the
1609  * latter case, the PATH component must not end in a dot.
1610  *
1611  * Both <NODE:> and <PATH> are optional. The <PATH> is a string
1612  * of hook names separated by dots. This breaks out the original
1613  * string, setting *nodep to "NODE" (or NULL if none) and *pathp
1614  * to "PATH" (or NULL if degenerate). Also, *hookp will point to
1615  * the final hook component of <PATH>, if any, otherwise NULL.
1616  *
1617  * This returns -1 if the path is malformed. The char ** are optional.
1618  ***********************************************************************/
1619 int
ng_path_parse(char * addr,char ** nodep,char ** pathp,char ** hookp)1620 ng_path_parse(char *addr, char **nodep, char **pathp, char **hookp)
1621 {
1622           char      *node, *path, *hook;
1623           int       k;
1624 
1625           /*
1626            * Extract absolute NODE, if any
1627            */
1628           for (path = addr; *path && *path != ':'; path++);
1629           if (*path) {
1630                     node = addr;        /* Here's the NODE */
1631                     *path++ = '\0';     /* Here's the PATH */
1632 
1633                     /* Node name must not be empty */
1634                     if (!*node)
1635                               return -1;
1636 
1637                     /* A name of "." is OK; otherwise '.' not allowed */
1638                     if (strcmp(node, ".") != 0) {
1639                               for (k = 0; node[k]; k++)
1640                                         if (node[k] == '.')
1641                                                   return -1;
1642                     }
1643           } else {
1644                     node = NULL;        /* No absolute NODE */
1645                     path = addr;        /* Here's the PATH */
1646           }
1647 
1648           /* Snoop for illegal characters in PATH */
1649           for (k = 0; path[k]; k++)
1650                     if (path[k] == ':')
1651                               return -1;
1652 
1653           /* Check for no repeated dots in PATH */
1654           for (k = 0; path[k]; k++)
1655                     if (path[k] == '.' && path[k + 1] == '.')
1656                               return -1;
1657 
1658           /* Remove extra (degenerate) dots from beginning or end of PATH */
1659           if (path[0] == '.')
1660                     path++;
1661           if (*path && path[strlen(path) - 1] == '.')
1662                     path[strlen(path) - 1] = 0;
1663 
1664           /* If PATH has a dot, then we're not talking about a hook */
1665           if (*path) {
1666                     for (hook = path, k = 0; path[k]; k++)
1667                               if (path[k] == '.') {
1668                                         hook = NULL;
1669                                         break;
1670                               }
1671           } else
1672                     path = hook = NULL;
1673 
1674           /* Done */
1675           if (nodep)
1676                     *nodep = node;
1677           if (pathp)
1678                     *pathp = path;
1679           if (hookp)
1680                     *hookp = hook;
1681           return (0);
1682 }
1683 
1684 /*
1685  * Given a path, which may be absolute or relative, and a starting node,
1686  * return the destination node.
1687  */
1688 int
ng_path2noderef(node_p here,const char * address,node_p * destp,hook_p * lasthook)1689 ng_path2noderef(node_p here, const char *address,
1690                                         node_p *destp, hook_p *lasthook)
1691 {
1692           char    fullpath[NG_PATHSIZ];
1693           char   *nodename, *path, pbuf[2];
1694           node_p  node, oldnode;
1695           char   *cp;
1696           hook_p hook = NULL;
1697 
1698           /* Initialize */
1699           if (destp == NULL) {
1700                     TRAP_ERROR();
1701                     return EINVAL;
1702           }
1703           *destp = NULL;
1704 
1705           /* Make a writable copy of address for ng_path_parse() */
1706           strncpy(fullpath, address, sizeof(fullpath) - 1);
1707           fullpath[sizeof(fullpath) - 1] = '\0';
1708 
1709           /* Parse out node and sequence of hooks */
1710           if (ng_path_parse(fullpath, &nodename, &path, NULL) < 0) {
1711                     TRAP_ERROR();
1712                     return EINVAL;
1713           }
1714           if (path == NULL) {
1715                     pbuf[0] = '.';      /* Needs to be writable */
1716                     pbuf[1] = '\0';
1717                     path = pbuf;
1718           }
1719 
1720           /*
1721            * For an absolute address, jump to the starting node.
1722            * Note that this holds a reference on the node for us.
1723            * Don't forget to drop the reference if we don't need it.
1724            */
1725           if (nodename) {
1726                     node = ng_name2noderef(here, nodename);
1727                     if (node == NULL) {
1728                               TRAP_ERROR();
1729                               return (ENOENT);
1730                     }
1731           } else {
1732                     if (here == NULL) {
1733                               TRAP_ERROR();
1734                               return (EINVAL);
1735                     }
1736                     node = here;
1737                     NG_NODE_REF(node);
1738           }
1739 
1740           /*
1741            * Now follow the sequence of hooks
1742            * XXX
1743            * We actually cannot guarantee that the sequence
1744            * is not being demolished as we crawl along it
1745            * without extra-ordinary locking etc.
1746            * So this is a bit dodgy to say the least.
1747            * We can probably hold up some things by holding
1748            * the nodelist mutex for the time of this
1749            * crawl if we wanted.. At least that way we wouldn't have to
1750            * worry about the nodes disappearing, but the hooks would still
1751            * be a problem.
1752            */
1753           for (cp = path; node != NULL && *cp != '\0'; ) {
1754                     char *segment;
1755 
1756                     /*
1757                      * Break out the next path segment. Replace the dot we just
1758                      * found with a NUL; "cp" points to the next segment (or the
1759                      * NUL at the end).
1760                      */
1761                     for (segment = cp; *cp != '\0'; cp++) {
1762                               if (*cp == '.') {
1763                                         *cp++ = '\0';
1764                                         break;
1765                               }
1766                     }
1767 
1768                     /* Empty segment */
1769                     if (*segment == '\0')
1770                               continue;
1771 
1772                     /* We have a segment, so look for a hook by that name */
1773                     hook = ng_findhook(node, segment);
1774 
1775                     /* Can't get there from here... */
1776                     if (hook == NULL
1777                         || NG_HOOK_PEER(hook) == NULL
1778                         || NG_HOOK_NOT_VALID(hook)
1779                         || NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook))) {
1780                               TRAP_ERROR();
1781                               NG_NODE_UNREF(node);
1782 #if 0
1783                               kprintf("hooknotvalid %s %s %d %d %d %d ",
1784                                                   path,
1785                                                   segment,
1786                                                   hook == NULL,
1787                                                   NG_HOOK_PEER(hook) == NULL,
1788                                                   NG_HOOK_NOT_VALID(hook),
1789                                                   NG_HOOK_NOT_VALID(NG_HOOK_PEER(hook)));
1790 #endif
1791                               return (ENOENT);
1792                     }
1793 
1794                     /*
1795                      * Hop on over to the next node
1796                      * XXX
1797                      * Big race conditions here as hooks and nodes go away
1798                      * *** Idea.. store an ng_ID_t in each hook and use that
1799                      * instead of the direct hook in this crawl?
1800                      */
1801                     oldnode = node;
1802                     if ((node = NG_PEER_NODE(hook)))
1803                               NG_NODE_REF(node);  /* XXX RACE */
1804                     NG_NODE_UNREF(oldnode);       /* XXX another race */
1805                     if (NG_NODE_NOT_VALID(node)) {
1806                               NG_NODE_UNREF(node);          /* XXX more races */
1807                               node = NULL;
1808                     }
1809           }
1810 
1811           /* If node somehow missing, fail here (probably this is not needed) */
1812           if (node == NULL) {
1813                     TRAP_ERROR();
1814                     return (ENXIO);
1815           }
1816 
1817           /* Done */
1818           *destp = node;
1819           if (lasthook != NULL)
1820                     *lasthook = (hook ? NG_HOOK_PEER(hook) : NULL);
1821           return (0);
1822 }
1823 
1824 /*********************************************************************\
1825 * Inter-CPU node synchronization
1826 *
1827 * All activities are submitted to one of the netgraph per-CPU threads.
1828 * There is one item input queue per CPU, not one per node as in
1829 * FreeBSD.  If the item is entering netgraph for the first time, it is
1830 * queued to the thread's msgport.  Otherwise it is applied directly.
1831 * From start to finish, the item is processed on the same CPU.  Items
1832 * are distributed based on the ingress node, to keep item ordering.
1833 \***************************************************************/
1834 
1835 static __inline void          ng_acquire_read(node_p node);
1836 static __inline void          ng_acquire_write(node_p node);
1837 static __inline void          ng_leave_readwrite(node_p node);
1838 
1839 static __inline void
ng_acquire_read(node_p node)1840 ng_acquire_read(node_p node)
1841 {
1842           KASSERT(node != &ng_deadnode,
1843               ("%s: working on deadnode", __func__));
1844 
1845           lwkt_gettoken_shared(&node->nd_token);
1846 }
1847 
1848 /* Acquire writer lock on node. If node is busy, sleep. */
1849 static __inline void
ng_acquire_write(node_p node)1850 ng_acquire_write(node_p node)
1851 {
1852           KASSERT(node != &ng_deadnode,
1853               ("%s: working on deadnode", __func__));
1854 
1855           lwkt_gettoken(&node->nd_token);
1856 }
1857 
1858 /* Release reader or writer lock. */
1859 static __inline void
ng_leave_readwrite(node_p node)1860 ng_leave_readwrite(node_p node)
1861 {
1862           lwkt_reltoken(&node->nd_token);
1863 }
1864 
1865 /***********************************************************************
1866 * Worklist routines
1867 **********************************************************************/
1868 /* NETGRAPH thread routine
1869  *
1870  * Pick an item from our thread's queue and apply it.
1871  */
1872 static void
ngthread(void * dummy __unused)1873 ngthread(void *dummy __unused)
1874 {
1875           lwkt_msg_t msg;
1876 
1877           while ((msg = lwkt_waitport(&curthread->td_msgport, 0)) != NULL) {
1878                     item_p  item = (void *)msg;
1879 
1880                     ng_apply_item(item);
1881                     /* Do not reply to the message */
1882           }
1883 }
1884 
1885 /***********************************************************************
1886 * Externally visible method for sending or queueing messages or data.
1887 ***********************************************************************/
1888 
1889 /*
1890  * The module code should have filled out the item correctly by this stage:
1891  * Common:
1892  *    reference to destination node.
1893  *    Reference to destination rcv hook if relevant.
1894  *    apply pointer must be or NULL or reference valid struct ng_apply_info.
1895  * Data:
1896  *    pointer to mbuf
1897  * Control_Message:
1898  *    pointer to msg.
1899  *    ID of original sender node. (return address)
1900  * Function:
1901  *    Function pointer
1902  *    void * argument
1903  *    integer argument
1904  *
1905  * The nodes have several routines and macros to help with this task:
1906  */
1907 
1908 int
ng_snd_item(item_p item,int flags)1909 ng_snd_item(item_p item, int flags)
1910 {
1911           hook_p hook;
1912           node_p node;
1913           int error = 0;
1914 
1915           /* We are sending item, so it must be present! */
1916           KASSERT(item != NULL, ("ng_snd_item: item is NULL"));
1917 
1918 #ifdef    NETGRAPH_DEBUG
1919           _ngi_check(item, __FILE__, __LINE__);
1920 #endif
1921 
1922           /*
1923            * Every time an item is sent or forwarded we hold a reference on it
1924            * to postone the callback (if there is one) and item freedom.
1925            */
1926           ng_ref_item(item);
1927 
1928           /*
1929            * Node is never optional.
1930            */
1931           node = NGI_NODE(item);
1932           KASSERT(node != NULL, ("ng_snd_item: node is NULL"));
1933 
1934           /*
1935            * Valid hook and mbuf are mandatory for data.
1936            */
1937           hook = NGI_HOOK(item);
1938           if ((item->el_flags & NGQF_TYPE) == NGQF_DATA) {
1939                     KASSERT(hook != NULL, ("ng_snd_item: hook for data is NULL"));
1940                     if (NGI_M(item) == NULL)
1941                               ERROUT(EINVAL);
1942                     CHECK_DATA_MBUF(NGI_M(item));
1943           }
1944 
1945           /*
1946            * Always queue items entering netgraph for the first time.
1947            */
1948           if (item->refs == 1) {
1949                     struct lwkt_msg *msg = &item->el_lmsg;
1950 
1951                     lwkt_initmsg(msg, &ng_panic_reply_port, 0);
1952                     /* Always send to cpu0 for now */
1953                     lwkt_sendmsg(ng_cpuport(0), msg);
1954 
1955                     return ((flags & NG_PROGRESS) ? EINPROGRESS : 0);
1956           }
1957 
1958           /*
1959            * The item wasn't queued.  Process it synchronously.
1960            */
1961           error = ng_apply_item(item);
1962 
1963 done:
1964           return (error);
1965 }
1966 
1967 /*
1968  * We have an item that was possibly queued somewhere.
1969  * It should contain all the information needed
1970  * to run it on the appropriate node/hook.
1971  * If there is apply pointer and we own the last reference, call apply().
1972  */
1973 static int
ng_apply_item(item_p item)1974 ng_apply_item(item_p item)
1975 {
1976           hook_p  hook;
1977           node_p    node;
1978           ng_rcvdata_t *rcvdata;
1979           ng_rcvmsg_t *rcvmsg;
1980           int       error = 0;
1981 
1982           /* Node and item are never optional. */
1983           KASSERT(item != NULL, ("ng_apply_item: item is NULL"));
1984           NGI_GET_NODE(item, node);               /* zaps stored node */
1985           KASSERT(node != NULL, ("ng_apply_item: node is NULL"));
1986           NGI_GET_HOOK(item, hook);               /* clears stored hook */
1987 
1988           /*
1989            * If the item or the node specifies single threading, force
1990            * writer semantics. Similarly, the node may say one hook always
1991            * produces writers. These are overrides.
1992            */
1993           if (((item->el_flags & NGQF_RW) == NGQF_WRITER) ||
1994               (node->nd_flags & NGF_FORCE_WRITER) ||
1995               (hook && (hook->hk_flags & HK_FORCE_WRITER))) {
1996                     ng_acquire_write(node);
1997           } else {
1998                     ng_acquire_read(node);
1999           }
2000 
2001 #ifdef    NETGRAPH_DEBUG
2002           _ngi_check(item, __FILE__, __LINE__);
2003 #endif
2004 
2005           switch (item->el_flags & NGQF_TYPE) {
2006           case NGQF_DATA:
2007                     /*
2008                      * Check things are still ok as when we were queued.
2009                      */
2010                     KASSERT(hook != NULL, ("ng_apply_item: hook for data is NULL"));
2011                     if (NG_HOOK_NOT_VALID(hook) ||
2012                         NG_NODE_NOT_VALID(node)) {
2013                               error = EIO;
2014                               NG_FREE_ITEM(item);
2015                               break;
2016                     }
2017                     /*
2018                      * If no receive method, just silently drop it.
2019                      * Give preference to the hook over-ride method
2020                      */
2021                     if ((!(rcvdata = hook->hk_rcvdata))
2022                     && (!(rcvdata = NG_HOOK_NODE(hook)->nd_type->rcvdata))) {
2023                               error = 0;
2024                               NG_FREE_ITEM(item);
2025                               break;
2026                     }
2027                     error = (*rcvdata)(hook, item);
2028                     break;
2029           case NGQF_MESG:
2030                     if (hook && NG_HOOK_NOT_VALID(hook)) {
2031                               /*
2032                                * The hook has been zapped then we can't use it.
2033                                * Immediately drop its reference.
2034                                * The message may not need it.
2035                                */
2036                               NG_HOOK_UNREF(hook);
2037                               hook = NULL;
2038                     }
2039                     /*
2040                      * Similarly, if the node is a zombie there is
2041                      * nothing we can do with it, drop everything.
2042                      */
2043                     if (NG_NODE_NOT_VALID(node)) {
2044                               TRAP_ERROR();
2045                               error = EINVAL;
2046                               NG_FREE_ITEM(item);
2047                               break;
2048                     }
2049                     /*
2050                      * Call the appropriate message handler for the object.
2051                      * It is up to the message handler to free the message.
2052                      * If it's a generic message, handle it generically,
2053                      * otherwise call the type's message handler (if it exists).
2054                      * XXX (race). Remember that a queued message may
2055                      * reference a node or hook that has just been
2056                      * invalidated. It will exist as the queue code
2057                      * is holding a reference, but..
2058                      */
2059                     if ((NGI_MSG(item)->header.typecookie == NGM_GENERIC_COOKIE) &&
2060                         ((NGI_MSG(item)->header.flags & NGF_RESP) == 0)) {
2061                               error = ng_generic_msg(node, item, hook);
2062                               break;
2063                     }
2064                     if (((!hook) || (!(rcvmsg = hook->hk_rcvmsg))) &&
2065                         (!(rcvmsg = node->nd_type->rcvmsg))) {
2066                               TRAP_ERROR();
2067                               error = 0;
2068                               NG_FREE_ITEM(item);
2069                               break;
2070                     }
2071                     error = (*rcvmsg)(node, item, hook);
2072                     break;
2073           case NGQF_FN:
2074           case NGQF_FN2:
2075                     /*
2076                      *  We have to implicitly trust the hook,
2077                      * as some of these are used for system purposes
2078                      * where the hook is invalid. In the case of
2079                      * the shutdown message we allow it to hit
2080                      * even if the node is invalid.
2081                      */
2082                     if ((NG_NODE_NOT_VALID(node))
2083                     && (NGI_FN(item) != &ng_rmnode)) {
2084                               TRAP_ERROR();
2085                               error = EINVAL;
2086                               NG_FREE_ITEM(item);
2087                               break;
2088                     }
2089                     if ((item->el_flags & NGQF_TYPE) == NGQF_FN) {
2090                               (*NGI_FN(item))(node, hook, NGI_ARG1(item),
2091                                   NGI_ARG2(item));
2092                               NG_FREE_ITEM(item);
2093                     } else    /* it is NGQF_FN2 */
2094                               error = (*NGI_FN2(item))(node, item, hook);
2095                     break;
2096           }
2097           /*
2098            * We held references on some of the resources
2099            * that we took from the item. Now that we have
2100            * finished doing everything, drop those references.
2101            */
2102           if (hook)
2103                     NG_HOOK_UNREF(hook);
2104 
2105           /* Release our node's token */
2106           ng_leave_readwrite(node);
2107 
2108           /* Free the item if we own the last reference to it. */
2109           ng_unref_item(item, error);
2110 
2111           NG_NODE_UNREF(node);
2112 
2113           return (error);
2114 }
2115 
2116 /***********************************************************************
2117  * Implement the 'generic' control messages
2118  ***********************************************************************/
2119 static int
ng_generic_msg(node_p here,item_p item,hook_p lasthook)2120 ng_generic_msg(node_p here, item_p item, hook_p lasthook)
2121 {
2122           int error = 0;
2123           struct ng_mesg *msg;
2124           struct ng_mesg *resp = NULL;
2125 
2126           NGI_GET_MSG(item, msg);
2127           if (msg->header.typecookie != NGM_GENERIC_COOKIE) {
2128                     TRAP_ERROR();
2129                     error = EINVAL;
2130                     goto out;
2131           }
2132           switch (msg->header.cmd) {
2133           case NGM_SHUTDOWN:
2134                     ng_rmnode(here, NULL, NULL, 0);
2135                     break;
2136           case NGM_MKPEER:
2137               {
2138                     struct ngm_mkpeer *const mkp = (struct ngm_mkpeer *) msg->data;
2139 
2140                     if (msg->header.arglen != sizeof(*mkp)) {
2141                               TRAP_ERROR();
2142                               error = EINVAL;
2143                               break;
2144                     }
2145                     mkp->type[sizeof(mkp->type) - 1] = '\0';
2146                     mkp->ourhook[sizeof(mkp->ourhook) - 1] = '\0';
2147                     mkp->peerhook[sizeof(mkp->peerhook) - 1] = '\0';
2148                     error = ng_mkpeer(here, mkp->ourhook, mkp->peerhook, mkp->type);
2149                     break;
2150               }
2151           case NGM_CONNECT:
2152               {
2153                     struct ngm_connect *const con =
2154                               (struct ngm_connect *) msg->data;
2155                     node_p node2;
2156 
2157                     if (msg->header.arglen != sizeof(*con)) {
2158                               TRAP_ERROR();
2159                               error = EINVAL;
2160                               break;
2161                     }
2162                     con->path[sizeof(con->path) - 1] = '\0';
2163                     con->ourhook[sizeof(con->ourhook) - 1] = '\0';
2164                     con->peerhook[sizeof(con->peerhook) - 1] = '\0';
2165                     /* Don't forget we get a reference.. */
2166                     error = ng_path2noderef(here, con->path, &node2, NULL);
2167                     if (error)
2168                               break;
2169                     error = ng_con_nodes(item, here, con->ourhook,
2170                         node2, con->peerhook);
2171                     NG_NODE_UNREF(node2);
2172                     break;
2173               }
2174           case NGM_NAME:
2175               {
2176                     struct ngm_name *const nam = (struct ngm_name *) msg->data;
2177 
2178                     if (msg->header.arglen != sizeof(*nam)) {
2179                               TRAP_ERROR();
2180                               error = EINVAL;
2181                               break;
2182                     }
2183                     nam->name[sizeof(nam->name) - 1] = '\0';
2184                     error = ng_name_node(here, nam->name);
2185                     break;
2186               }
2187           case NGM_RMHOOK:
2188               {
2189                     struct ngm_rmhook *const rmh = (struct ngm_rmhook *) msg->data;
2190                     hook_p hook;
2191 
2192                     if (msg->header.arglen != sizeof(*rmh)) {
2193                               TRAP_ERROR();
2194                               error = EINVAL;
2195                               break;
2196                     }
2197                     rmh->ourhook[sizeof(rmh->ourhook) - 1] = '\0';
2198                     if ((hook = ng_findhook(here, rmh->ourhook)) != NULL)
2199                               ng_destroy_hook(hook);
2200                     break;
2201               }
2202           case NGM_NODEINFO:
2203               {
2204                     struct nodeinfo *ni;
2205 
2206                     NG_MKRESPONSE(resp, msg, sizeof(*ni), M_WAITOK | M_NULLOK);
2207                     if (resp == NULL) {
2208                               error = ENOMEM;
2209                               break;
2210                     }
2211 
2212                     /* Fill in node info */
2213                     ni = (struct nodeinfo *) resp->data;
2214                     if (NG_NODE_HAS_NAME(here))
2215                               strcpy(ni->name, NG_NODE_NAME(here));
2216                     strcpy(ni->type, here->nd_type->name);
2217                     ni->id = ng_node2ID(here);
2218                     ni->hooks = here->nd_numhooks;
2219                     break;
2220               }
2221           case NGM_LISTHOOKS:
2222               {
2223                     const int nhooks = here->nd_numhooks;
2224                     struct hooklist *hl;
2225                     struct nodeinfo *ni;
2226                     hook_p hook;
2227 
2228                     /* Get response struct */
2229                     NG_MKRESPONSE(resp, msg, sizeof(*hl)
2230                         + (nhooks * sizeof(struct linkinfo)), M_WAITOK | M_NULLOK);
2231                     if (resp == NULL) {
2232                               error = ENOMEM;
2233                               break;
2234                     }
2235                     hl = (struct hooklist *) resp->data;
2236                     ni = &hl->nodeinfo;
2237 
2238                     /* Fill in node info */
2239                     if (NG_NODE_HAS_NAME(here))
2240                               strcpy(ni->name, NG_NODE_NAME(here));
2241                     strcpy(ni->type, here->nd_type->name);
2242                     ni->id = ng_node2ID(here);
2243 
2244                     /* Cycle through the linked list of hooks */
2245                     ni->hooks = 0;
2246                     LIST_FOREACH(hook, &here->nd_hooks, hk_hooks) {
2247                               struct linkinfo *const link = &hl->link[ni->hooks];
2248 
2249                               if (ni->hooks >= nhooks) {
2250                                         log(LOG_ERR, "%s: number of %s changed\n",
2251                                             __func__, "hooks");
2252                                         break;
2253                               }
2254                               if (NG_HOOK_NOT_VALID(hook))
2255                                         continue;
2256                               strcpy(link->ourhook, NG_HOOK_NAME(hook));
2257                               strcpy(link->peerhook, NG_PEER_HOOK_NAME(hook));
2258                               if (NG_PEER_NODE_NAME(hook)[0] != '\0')
2259                                         strcpy(link->nodeinfo.name,
2260                                             NG_PEER_NODE_NAME(hook));
2261                               strcpy(link->nodeinfo.type,
2262                                  NG_PEER_NODE(hook)->nd_type->name);
2263                               link->nodeinfo.id = ng_node2ID(NG_PEER_NODE(hook));
2264                               link->nodeinfo.hooks = NG_PEER_NODE(hook)->nd_numhooks;
2265                               ni->hooks++;
2266                     }
2267                     break;
2268               }
2269 
2270           case NGM_LISTNODES:
2271               {
2272                     struct namelist *nl;
2273                     node_p node;
2274                     int i;
2275 
2276                     IDHASH_RLOCK();
2277                     /* Get response struct. */
2278                     NG_MKRESPONSE(resp, msg, sizeof(*nl) +
2279                         (ng_nodes * sizeof(struct nodeinfo)), M_NOWAIT | M_ZERO);
2280                     if (resp == NULL) {
2281                               IDHASH_RUNLOCK();
2282                               error = ENOMEM;
2283                               break;
2284                     }
2285                     nl = (struct namelist *) resp->data;
2286 
2287                     /* Cycle through the lists of nodes. */
2288                     nl->numnames = 0;
2289                     for (i = 0; i <= ng_ID_hmask; i++) {
2290                               LIST_FOREACH(node, &ng_ID_hash[i], nd_idnodes) {
2291                                         struct nodeinfo *const np =
2292                                             &nl->nodeinfo[nl->numnames];
2293 
2294                                         if (NG_NODE_NOT_VALID(node))
2295                                                   continue;
2296                                         if (NG_NODE_HAS_NAME(node))
2297                                                   strcpy(np->name, NG_NODE_NAME(node));
2298                                         strcpy(np->type, node->nd_type->name);
2299                                         np->id = ng_node2ID(node);
2300                                         np->hooks = node->nd_numhooks;
2301                                         KASSERT(nl->numnames < ng_nodes,
2302                                             ("%s: no space", __func__));
2303                                         nl->numnames++;
2304                               }
2305                     }
2306                     IDHASH_RUNLOCK();
2307                     break;
2308               }
2309           case NGM_LISTNAMES:
2310               {
2311                     struct namelist *nl;
2312                     node_p node;
2313                     int i;
2314 
2315                     NAMEHASH_RLOCK();
2316                     /* Get response struct. */
2317                     NG_MKRESPONSE(resp, msg, sizeof(*nl) +
2318                         (ng_named_nodes * sizeof(struct nodeinfo)), M_NOWAIT);
2319                     if (resp == NULL) {
2320                               NAMEHASH_RUNLOCK();
2321                               error = ENOMEM;
2322                               break;
2323                     }
2324                     nl = (struct namelist *) resp->data;
2325 
2326                     /* Cycle through the lists of nodes. */
2327                     nl->numnames = 0;
2328                     for (i = 0; i <= ng_name_hmask; i++) {
2329                               LIST_FOREACH(node, &ng_name_hash[i], nd_nodes) {
2330                                         struct nodeinfo *const np =
2331                                             &nl->nodeinfo[nl->numnames];
2332 
2333                                         if (NG_NODE_NOT_VALID(node))
2334                                                   continue;
2335                                         strcpy(np->name, NG_NODE_NAME(node));
2336                                         strcpy(np->type, node->nd_type->name);
2337                                         np->id = ng_node2ID(node);
2338                                         np->hooks = node->nd_numhooks;
2339                                         KASSERT(nl->numnames < ng_named_nodes,
2340                                             ("%s: no space", __func__));
2341                                         nl->numnames++;
2342                               }
2343                     }
2344                     NAMEHASH_RUNLOCK();
2345                     break;
2346               }
2347 
2348           case NGM_LISTTYPES:
2349               {
2350                     struct typelist *tl;
2351                     struct ng_type *type;
2352                     int num = 0;
2353 
2354                     TYPELIST_RLOCK();
2355                     /* Count number of types */
2356                     LIST_FOREACH(type, &ng_typelist, types)
2357                               num++;
2358 
2359                     /* Get response struct */
2360                     NG_MKRESPONSE(resp, msg, sizeof(*tl)
2361                         + (num * sizeof(struct typeinfo)), M_WAITOK | M_NULLOK);
2362                     if (resp == NULL) {
2363                               TYPELIST_RUNLOCK();
2364                               error = ENOMEM;
2365                               break;
2366                     }
2367                     tl = (struct typelist *) resp->data;
2368 
2369                     /* Cycle through the linked list of types */
2370                     tl->numtypes = 0;
2371                     LIST_FOREACH(type, &ng_typelist, types) {
2372                               struct typeinfo *const tp = &tl->typeinfo[tl->numtypes];
2373 
2374                               strcpy(tp->type_name, type->name);
2375                               tp->numnodes = type->refs - 1; /* don't count list */
2376                               KASSERT(tl->numtypes < num, ("%s: no space", __func__));
2377                               tl->numtypes++;
2378                     }
2379                     TYPELIST_RUNLOCK();
2380                     break;
2381               }
2382 
2383           case NGM_BINARY2ASCII:
2384               {
2385                     int bufSize = 20 * 1024;      /* XXX hard coded constant */
2386                     const struct ng_parse_type *argstype;
2387                     const struct ng_cmdlist *c;
2388                     struct ng_mesg *binary, *ascii;
2389 
2390                     /* Data area must contain a valid netgraph message */
2391                     binary = (struct ng_mesg *)msg->data;
2392                     if (msg->header.arglen < sizeof(struct ng_mesg) ||
2393                         (msg->header.arglen - sizeof(struct ng_mesg) <
2394                         binary->header.arglen)) {
2395                               TRAP_ERROR();
2396                               error = EINVAL;
2397                               break;
2398                     }
2399 
2400                     /* Get a response message with lots of room */
2401                     NG_MKRESPONSE(resp, msg, sizeof(*ascii) + bufSize, M_WAITOK | M_NULLOK);
2402                     if (resp == NULL) {
2403                               error = ENOMEM;
2404                               break;
2405                     }
2406                     ascii = (struct ng_mesg *)resp->data;
2407 
2408                     /* Copy binary message header to response message payload */
2409                     bcopy(binary, ascii, sizeof(*binary));
2410 
2411                     /* Find command by matching typecookie and command number */
2412                     for (c = here->nd_type->cmdlist;
2413                         c != NULL && c->name != NULL; c++) {
2414                               if (binary->header.typecookie == c->cookie
2415                                   && binary->header.cmd == c->cmd)
2416                                         break;
2417                     }
2418                     if (c == NULL || c->name == NULL) {
2419                               for (c = ng_generic_cmds; c->name != NULL; c++) {
2420                                         if (binary->header.typecookie == c->cookie
2421                                             && binary->header.cmd == c->cmd)
2422                                                   break;
2423                               }
2424                               if (c->name == NULL) {
2425                                         NG_FREE_MSG(resp);
2426                                         error = ENOSYS;
2427                                         break;
2428                               }
2429                     }
2430 
2431                     /* Convert command name to ASCII */
2432                     ksnprintf(ascii->header.cmdstr, sizeof(ascii->header.cmdstr),
2433                         "%s", c->name);
2434 
2435                     /* Convert command arguments to ASCII */
2436                     argstype = (binary->header.flags & NGF_RESP) ?
2437                         c->respType : c->mesgType;
2438                     if (argstype == NULL) {
2439                               *ascii->data = '\0';
2440                     } else {
2441                               if ((error = ng_unparse(argstype,
2442                                   (u_char *)binary->data,
2443                                   ascii->data, bufSize)) != 0) {
2444                                         NG_FREE_MSG(resp);
2445                                         break;
2446                               }
2447                     }
2448 
2449                     /* Return the result as struct ng_mesg plus ASCII string */
2450                     bufSize = strlen(ascii->data) + 1;
2451                     ascii->header.arglen = bufSize;
2452                     resp->header.arglen = sizeof(*ascii) + bufSize;
2453                     break;
2454               }
2455 
2456           case NGM_ASCII2BINARY:
2457               {
2458                     int bufSize = 2000; /* XXX hard coded constant */
2459                     const struct ng_cmdlist *c;
2460                     const struct ng_parse_type *argstype;
2461                     struct ng_mesg *ascii, *binary;
2462                     int off = 0;
2463 
2464                     /* Data area must contain at least a struct ng_mesg + '\0' */
2465                     ascii = (struct ng_mesg *)msg->data;
2466                     if ((msg->header.arglen < sizeof(*ascii) + 1) ||
2467                         (ascii->header.arglen < 1) ||
2468                         (msg->header.arglen < sizeof(*ascii) +
2469                         ascii->header.arglen)) {
2470                               TRAP_ERROR();
2471                               error = EINVAL;
2472                               break;
2473                     }
2474                     ascii->data[ascii->header.arglen - 1] = '\0';
2475 
2476                     /* Get a response message with lots of room */
2477                     NG_MKRESPONSE(resp, msg, sizeof(*binary) + bufSize, M_WAITOK | M_NULLOK);
2478                     if (resp == NULL) {
2479                               error = ENOMEM;
2480                               break;
2481                     }
2482                     binary = (struct ng_mesg *)resp->data;
2483 
2484                     /* Copy ASCII message header to response message payload */
2485                     bcopy(ascii, binary, sizeof(*ascii));
2486 
2487                     /* Find command by matching ASCII command string */
2488                     for (c = here->nd_type->cmdlist;
2489                         c != NULL && c->name != NULL; c++) {
2490                               if (strcmp(ascii->header.cmdstr, c->name) == 0)
2491                                         break;
2492                     }
2493                     if (c == NULL || c->name == NULL) {
2494                               for (c = ng_generic_cmds; c->name != NULL; c++) {
2495                                         if (strcmp(ascii->header.cmdstr, c->name) == 0)
2496                                                   break;
2497                               }
2498                               if (c->name == NULL) {
2499                                         NG_FREE_MSG(resp);
2500                                         error = ENOSYS;
2501                                         break;
2502                               }
2503                     }
2504 
2505                     /* Convert command name to binary */
2506                     binary->header.cmd = c->cmd;
2507                     binary->header.typecookie = c->cookie;
2508 
2509                     /* Convert command arguments to binary */
2510                     argstype = (binary->header.flags & NGF_RESP) ?
2511                         c->respType : c->mesgType;
2512                     if (argstype == NULL) {
2513                               bufSize = 0;
2514                     } else {
2515                               if ((error = ng_parse(argstype, ascii->data,
2516                                   &off, (u_char *)binary->data, &bufSize)) != 0) {
2517                                         NG_FREE_MSG(resp);
2518                                         break;
2519                               }
2520                     }
2521 
2522                     /* Return the result */
2523                     binary->header.arglen = bufSize;
2524                     resp->header.arglen = sizeof(*binary) + bufSize;
2525                     break;
2526               }
2527 
2528           case NGM_TEXT_CONFIG:
2529           case NGM_TEXT_STATUS:
2530                     /*
2531                      * This one is tricky as it passes the command down to the
2532                      * actual node, even though it is a generic type command.
2533                      * This means we must assume that the item/msg is already freed
2534                      * when control passes back to us.
2535                      */
2536                     if (here->nd_type->rcvmsg != NULL) {
2537                               NGI_MSG(item) = msg; /* put it back as we found it */
2538                               return((*here->nd_type->rcvmsg)(here, item, lasthook));
2539                     }
2540                     /* Fall through if rcvmsg not supported */
2541           default:
2542                     TRAP_ERROR();
2543                     error = EINVAL;
2544           }
2545           /*
2546            * Sometimes a generic message may be statically allocated
2547            * to avoid problems with allocating when in tight memeory situations.
2548            * Don't free it if it is so.
2549            * I break them appart here, because erros may cause a free if the item
2550            * in which case we'd be doing it twice.
2551            * they are kept together above, to simplify freeing.
2552            */
2553 out:
2554           NG_RESPOND_MSG(error, here, item, resp);
2555           if (msg)
2556                     NG_FREE_MSG(msg);
2557           return (error);
2558 }
2559 
2560 /************************************************************************
2561                               Queue element get/free routines
2562 ************************************************************************/
2563 
2564 static struct objcache        *ng_oc;
2565 static struct objcache        *ng_apply_oc;
2566 static int                     maxalloc = 4096; /* limit the damage of a leak */
2567 
2568 TUNABLE_INT("net.graph.maxalloc", &maxalloc);
2569 SYSCTL_INT(_net_graph, OID_AUTO, maxalloc, CTLFLAG_RD, &maxalloc,
2570     0, "Maximum number of queue items to allocate");
2571 
2572 #ifdef    NETGRAPH_DEBUG
2573 static TAILQ_HEAD(, ng_item) ng_itemlist = TAILQ_HEAD_INITIALIZER(ng_itemlist);
2574 static int                              allocated;          /* number of items malloc'd */
2575 #endif
2576 
2577 /*
2578  * Get a queue entry.
2579  * This is usually called when a packet first enters netgraph.
2580  * By definition, this is usually from an interrupt, or from a user.
2581  * Users are not so important, but try be quick for the times that it's
2582  * an interrupt.
2583  */
2584 static __inline item_p
ng_alloc_item(int type,int flags)2585 ng_alloc_item(int type, int flags)
2586 {
2587           item_p item;
2588 
2589           KASSERT(((type & ~NGQF_TYPE) == 0),
2590               ("%s: incorrect item type: %d", __func__, type));
2591 
2592           item = objcache_get(ng_oc,
2593               (flags & NG_WAITOK) ? M_WAITOK : M_NOWAIT );
2594 
2595           if (item) {
2596                     item->el_flags = type;
2597 #ifdef    NETGRAPH_DEBUG
2598                     mtx_lock(&ngq_mtx);
2599                     TAILQ_INSERT_TAIL(&ng_itemlist, item, all);
2600                     allocated++;
2601                     mtx_unlock(&ngq_mtx);
2602 #endif
2603           }
2604 
2605           return (item);
2606 }
2607 
2608 /*
2609  * Release a queue entry
2610  */
2611 void
ng_free_item(item_p item)2612 ng_free_item(item_p item)
2613 {
2614           /*
2615            * If the item still has an apply callback registered, it is
2616            * being freed too early.
2617            */
2618           KASSERT(item->apply == NULL, ("freeing item with registered callback"));
2619 
2620           /*
2621            * Make sure the reference count has reached zero.
2622            */
2623           KASSERT(item->refs == 0, ("freeing item with non-zero refcount"));
2624 
2625           /*
2626            * The item may hold resources on it's own. We need to free
2627            * these before we can free the item. What they are depends upon
2628            * what kind of item it is. it is important that nodes zero
2629            * out pointers to resources that they remove from the item
2630            * or we release them again here.
2631            */
2632           switch (item->el_flags & NGQF_TYPE) {
2633           case NGQF_DATA:
2634                     /* If we have an mbuf still attached.. */
2635                     NG_FREE_M(_NGI_M(item));
2636                     break;
2637           case NGQF_MESG:
2638                     _NGI_RETADDR(item) = 0;
2639                     NG_FREE_MSG(_NGI_MSG(item));
2640                     break;
2641           case NGQF_FN:
2642           case NGQF_FN2:
2643                     /* nothing to free really, */
2644                     _NGI_FN(item) = NULL;
2645                     _NGI_ARG1(item) = NULL;
2646                     _NGI_ARG2(item) = 0;
2647                     break;
2648           }
2649           /* If we still have a node or hook referenced... */
2650           _NGI_CLR_NODE(item);
2651           _NGI_CLR_HOOK(item);
2652 
2653 #ifdef    NETGRAPH_DEBUG
2654           mtx_lock(&ngq_mtx);
2655           TAILQ_REMOVE(&ng_itemlist, item, all);
2656           allocated--;
2657           mtx_unlock(&ngq_mtx);
2658 #endif
2659           /* Object must be initialized before returning to objcache */
2660           bzero(item, sizeof(struct ng_item));
2661           objcache_put(ng_oc, item);
2662 }
2663 
2664 /*
2665  * Change type of the queue entry.
2666  */
2667 static __inline item_p
ng_realloc_item(item_p item,int type,int flags)2668 ng_realloc_item(item_p item, int type, int flags)
2669 {
2670 
2671           KASSERT((item != NULL), ("%s: can't reallocate NULL", __func__));
2672           KASSERT(((type & ~NGQF_TYPE) == 0),
2673               ("%s: incorrect item type: %d", __func__, type));
2674 
2675           item->el_flags = (item->el_flags & ~NGQF_TYPE) | type;
2676 
2677           return (item);
2678 }
2679 
2680 __inline apply_p
ng_alloc_apply(void)2681 ng_alloc_apply(void)
2682 {
2683           return (objcache_get(ng_apply_oc, M_WAITOK));
2684 }
2685 
2686 __inline void
ng_free_apply(apply_p apply)2687 ng_free_apply(apply_p apply)
2688 {
2689           objcache_put(ng_apply_oc, apply);
2690 }
2691 
2692 /************************************************************************
2693                               Module routines
2694 ************************************************************************/
2695 
2696 /*
2697  * Handle the loading/unloading of a netgraph node type module
2698  */
2699 int
ng_mod_event(module_t mod,int event,void * data)2700 ng_mod_event(module_t mod, int event, void *data)
2701 {
2702           struct ng_type *const type = data;
2703           int error = 0;
2704 
2705           switch (event) {
2706           case MOD_LOAD:
2707 
2708                     /* Register new netgraph node type */
2709                     if ((error = ng_newtype(type)) != 0) {
2710                               break;
2711                     }
2712 
2713                     /* Call type specific code */
2714                     if (type->mod_event != NULL)
2715                               if ((error = (*type->mod_event)(mod, event, data))) {
2716                                         TYPELIST_WLOCK();
2717                                         type->refs--;       /* undo it */
2718                                         LIST_REMOVE(type, types);
2719                                         TYPELIST_WUNLOCK();
2720                               }
2721                     break;
2722 
2723           case MOD_UNLOAD:
2724                     if (type->refs > 1) {                   /* make sure no nodes exist! */
2725                               error = EBUSY;
2726                     } else {
2727                               if (type->refs == 0) {
2728                                         /* failed load, nothing to undo */
2729                                         break;
2730                               }
2731                               if (type->mod_event != NULL) {          /* check with type */
2732                                         error = (*type->mod_event)(mod, event, data);
2733                                         if (error != 0) {   /* type refuses.. */
2734                                                   break;
2735                                         }
2736                               }
2737                               TYPELIST_WLOCK();
2738                               LIST_REMOVE(type, types);
2739                               TYPELIST_WUNLOCK();
2740                     }
2741                     break;
2742 
2743           default:
2744                     if (type->mod_event != NULL)
2745                               error = (*type->mod_event)(mod, event, data);
2746                     else
2747                               error = EOPNOTSUPP;           /* XXX ? */
2748                     break;
2749           }
2750           return (error);
2751 }
2752 
2753 /*
2754  * Handle loading and unloading for this code.
2755  */
2756 static int
ngb_mod_event(module_t mod,int event,void * data)2757 ngb_mod_event(module_t mod, int event, void *data)
2758 {
2759           int i, error = 0;
2760 
2761           switch (event) {
2762           case MOD_LOAD:
2763                     /* Initialize everything. */
2764                     lwkt_token_init(&ng_typelist_token, "ng typelist");
2765                     lwkt_token_init(&ng_idhash_token, "ng idhash");
2766                     lwkt_token_init(&ng_namehash_token, "ng namehash");
2767                     lwkt_token_init(&ng_topo_token, "ng topology");
2768 #ifdef    NETGRAPH_DEBUG
2769                     mtx_init(&ng_nodelist_mtx, "ng nodelist");
2770                     mtx_init(&ngq_mtx, "ng queue");
2771 #endif
2772                     ng_oc = objcache_create_mbacked(M_NETGRAPH,
2773                                   sizeof(struct ng_item), maxalloc, 0, bzero_ctor,
2774                                   NULL, NULL);
2775                     ng_apply_oc = objcache_create_mbacked(M_NETGRAPH_APPLY,
2776                                   sizeof(struct ng_apply_info), 0, 0, bzero_ctor,
2777                                   NULL, NULL);
2778 
2779                     /* We start with small hashes, but they can grow. */
2780                     ng_ID_hash = hashinit(16, M_NETGRAPH_NODE, &ng_ID_hmask);
2781                     ng_name_hash = hashinit(16, M_NETGRAPH_NODE, &ng_name_hmask);
2782 
2783                     lwkt_initport_panic(&ng_panic_reply_port);
2784                     for (i = 0; i < ncpus; ++i) {
2785                               thread_t td;
2786 
2787                               lwkt_create(ngthread, NULL, &td,
2788                                  NULL, 0, i, "netgraph %d", i);
2789                               ng_msgport[i] = &td->td_msgport;
2790                     }
2791                     break;
2792           case MOD_UNLOAD:
2793 #if 0
2794                     hashdestroy(V_ng_name_hash, M_NETGRAPH_NODE, V_ng_name_hmask);
2795                     hashdestroy(V_ng_ID_hash, M_NETGRAPH_NODE, V_ng_ID_hmask);
2796 
2797                     /* Destroy the lwkt threads too */
2798 
2799                     objcache_destroy(ng_apply_oc);
2800                     objcache_destroy(ng_oc);
2801 #endif
2802                     /* You can't unload it because an interface may be using it. */
2803                     error = EBUSY;
2804                     break;
2805           default:
2806                     error = EOPNOTSUPP;
2807                     break;
2808           }
2809           return (error);
2810 }
2811 
2812 static moduledata_t netgraph_mod = {
2813           "netgraph",
2814           ngb_mod_event,
2815           (NULL)
2816 };
2817 DECLARE_MODULE(netgraph, netgraph_mod, SI_SUB_NETGRAPH, SI_ORDER_MIDDLE);
2818 SYSCTL_NODE(_net, OID_AUTO, graph, CTLFLAG_RW, 0, "netgraph Family");
2819 SYSCTL_INT(_net_graph, OID_AUTO, abi_version, CTLFLAG_RD, 0, NG_ABI_VERSION,"");
2820 SYSCTL_INT(_net_graph, OID_AUTO, msg_version, CTLFLAG_RD, 0, NG_VERSION, "");
2821 
2822 #ifdef    NETGRAPH_DEBUG
2823 void
dumphook(hook_p hook,char * file,int line)2824 dumphook (hook_p hook, char *file, int line)
2825 {
2826           kprintf("hook: name %s, %d refs, Last touched:\n",
2827                     _NG_HOOK_NAME(hook), hook->hk_refs);
2828           kprintf(" Last active @ %s, line %d\n",
2829                     hook->lastfile, hook->lastline);
2830           if (line) {
2831                     kprintf(" problem discovered at file %s, line %d\n", file, line);
2832           }
2833 }
2834 
2835 void
dumpnode(node_p node,char * file,int line)2836 dumpnode(node_p node, char *file, int line)
2837 {
2838           kprintf("node: ID [%x]: type '%s', %d hooks, flags 0x%x, %d refs, %s:\n",
2839                     _NG_NODE_ID(node), node->nd_type->name,
2840                     node->nd_numhooks, node->nd_flags,
2841                     node->nd_refs, node->nd_name);
2842           kprintf(" Last active @ %s, line %d\n",
2843                     node->lastfile, node->lastline);
2844           if (line) {
2845                     kprintf(" problem discovered at file %s, line %d\n", file, line);
2846           }
2847 }
2848 
2849 void
dumpitem(item_p item,char * file,int line)2850 dumpitem(item_p item, char *file, int line)
2851 {
2852           kprintf(" ACTIVE item, last used at %s, line %d",
2853                     item->lastfile, item->lastline);
2854           switch(item->el_flags & NGQF_TYPE) {
2855           case NGQF_DATA:
2856                     kprintf(" - [data]\n");
2857                     break;
2858           case NGQF_MESG:
2859                     kprintf(" - retaddr[%d]:\n", _NGI_RETADDR(item));
2860                     break;
2861           case NGQF_FN:
2862                     kprintf(" - fn@%p (%p, %p, %p, %d (%x))\n",
2863                               _NGI_FN(item),
2864                               _NGI_NODE(item),
2865                               _NGI_HOOK(item),
2866                               item->body.fn.fn_arg1,
2867                               item->body.fn.fn_arg2,
2868                               item->body.fn.fn_arg2);
2869                     break;
2870           case NGQF_FN2:
2871                     kprintf(" - fn2@%p (%p, %p, %p, %d (%x))\n",
2872                               _NGI_FN2(item),
2873                               _NGI_NODE(item),
2874                               _NGI_HOOK(item),
2875                               item->body.fn.fn_arg1,
2876                               item->body.fn.fn_arg2,
2877                               item->body.fn.fn_arg2);
2878                     break;
2879           }
2880           if (line) {
2881                     kprintf(" problem discovered at file %s, line %d\n", file, line);
2882                     if (_NGI_NODE(item)) {
2883                               kprintf("node %p ([%x])\n",
2884                                         _NGI_NODE(item), ng_node2ID(_NGI_NODE(item)));
2885                     }
2886           }
2887 }
2888 
2889 static void
ng_dumpitems(void)2890 ng_dumpitems(void)
2891 {
2892           item_p item;
2893           int i = 1;
2894           TAILQ_FOREACH(item, &ng_itemlist, all) {
2895                     kprintf("[%d] ", i++);
2896                     dumpitem(item, NULL, 0);
2897           }
2898 }
2899 
2900 static void
ng_dumpnodes(void)2901 ng_dumpnodes(void)
2902 {
2903           node_p node;
2904           int i = 1;
2905           mtx_lock(&ng_nodelist_mtx);
2906           SLIST_FOREACH(node, &ng_allnodes, nd_all) {
2907                     kprintf("[%d] ", i++);
2908                     dumpnode(node, NULL, 0);
2909           }
2910           mtx_unlock(&ng_nodelist_mtx);
2911 }
2912 
2913 static void
ng_dumphooks(void)2914 ng_dumphooks(void)
2915 {
2916           hook_p hook;
2917           int i = 1;
2918           mtx_lock(&ng_nodelist_mtx);
2919           SLIST_FOREACH(hook, &ng_allhooks, hk_all) {
2920                     kprintf("[%d] ", i++);
2921                     dumphook(hook, NULL, 0);
2922           }
2923           mtx_unlock(&ng_nodelist_mtx);
2924 }
2925 
2926 static int
sysctl_debug_ng_dump_items(SYSCTL_HANDLER_ARGS)2927 sysctl_debug_ng_dump_items(SYSCTL_HANDLER_ARGS)
2928 {
2929           int error;
2930           int val;
2931 
2932           val = allocated;
2933           error = sysctl_handle_int(oidp, &val, 0, req);
2934           if (error != 0 || req->newptr == NULL)
2935                     return (error);
2936           if (val == 42) {
2937                     ng_dumpitems();
2938                     ng_dumpnodes();
2939                     ng_dumphooks();
2940           }
2941           return (0);
2942 }
2943 
2944 SYSCTL_PROC(_debug, OID_AUTO, ng_dump_items, CTLTYPE_INT | CTLFLAG_RW,
2945     0, sizeof(int), sysctl_debug_ng_dump_items, "I", "Number of allocated items");
2946 #endif    /* NETGRAPH_DEBUG */
2947 
2948 
2949 /***********************************************************************
2950 * Externally useable functions to set up a queue item ready for sending
2951 ***********************************************************************/
2952 
2953 #ifdef    NETGRAPH_DEBUG
2954 #define   ITEM_DEBUG_CHECKS                                                     \
2955           do {                                                                            \
2956                     if (NGI_NODE(item) ) {                                                \
2957                               kprintf("item already has node");                 \
2958                               kdb_enter(KDB_WHY_NETGRAPH, "has node");          \
2959                               NGI_CLR_NODE(item);                               \
2960                     }                                                                     \
2961                     if (NGI_HOOK(item) ) {                                                \
2962                               kprintf("item already has hook");                 \
2963                               kdb_enter(KDB_WHY_NETGRAPH, "has hook");          \
2964                               NGI_CLR_HOOK(item);                               \
2965                     }                                                                     \
2966           } while (0)
2967 #else
2968 #define ITEM_DEBUG_CHECKS
2969 #endif
2970 
2971 /*
2972  * Put mbuf into the item.
2973  * Hook and node references will be removed when the item is dequeued.
2974  * (or equivalent)
2975  * (XXX) Unsafe because no reference held by peer on remote node.
2976  * remote node might go away in this timescale.
2977  * We know the hooks can't go away because that would require getting
2978  * a writer item on both nodes and we must have at least a  reader
2979  * here to be able to do this.
2980  * Note that the hook loaded is the REMOTE hook.
2981  *
2982  * This is possibly in the critical path for new data.
2983  */
2984 item_p
ng_package_data(struct mbuf * m,int flags)2985 ng_package_data(struct mbuf *m, int flags)
2986 {
2987           item_p item;
2988 
2989           if ((item = ng_alloc_item(NGQF_DATA, flags)) == NULL) {
2990                     NG_FREE_M(m);
2991                     return (NULL);
2992           }
2993           ITEM_DEBUG_CHECKS;
2994           item->el_flags |= NGQF_READER;
2995           NGI_M(item) = m;
2996           return (item);
2997 }
2998 
2999 /*
3000  * Allocate a queue item and put items into it..
3001  * Evaluate the address as this will be needed to queue it and
3002  * to work out what some of the fields should be.
3003  * Hook and node references will be removed when the item is dequeued.
3004  * (or equivalent)
3005  */
3006 item_p
ng_package_msg(struct ng_mesg * msg,int flags)3007 ng_package_msg(struct ng_mesg *msg, int flags)
3008 {
3009           item_p item;
3010 
3011           if ((item = ng_alloc_item(NGQF_MESG, flags)) == NULL) {
3012                     NG_FREE_MSG(msg);
3013                     return (NULL);
3014           }
3015           ITEM_DEBUG_CHECKS;
3016           /* Messages items count as writers unless explicitly exempted. */
3017           if (msg->header.cmd & NGM_READONLY)
3018                     item->el_flags |= NGQF_READER;
3019           else
3020                     item->el_flags |= NGQF_WRITER;
3021           /*
3022            * Set the current lasthook into the queue item
3023            */
3024           NGI_MSG(item) = msg;
3025           NGI_RETADDR(item) = 0;
3026           return (item);
3027 }
3028 
3029 
3030 
3031 #define SET_RETADDR(item, here, retaddr)                                        \
3032           do {      /* Data or fn items don't have retaddrs */                  \
3033                     if ((item->el_flags & NGQF_TYPE) == NGQF_MESG) {  \
3034                               if (retaddr) {                                              \
3035                                         NGI_RETADDR(item) = retaddr;            \
3036                               } else {                                          \
3037                                         /*                                                \
3038                                          * The old return address should be ok. \
3039                                          * If there isn't one, use the address  \
3040                                          * here.                                \
3041                                          */                                               \
3042                                         if (NGI_RETADDR(item) == 0) {           \
3043                                                   NGI_RETADDR(item)             \
3044                                                             = ng_node2ID(here); \
3045                                         }                                                 \
3046                               }                                                           \
3047                     }                                                                     \
3048           } while (0)
3049 
3050 int
ng_address_hook(node_p here,item_p item,hook_p hook,ng_ID_t retaddr)3051 ng_address_hook(node_p here, item_p item, hook_p hook, ng_ID_t retaddr)
3052 {
3053           hook_p peer;
3054           node_p peernode;
3055           ITEM_DEBUG_CHECKS;
3056           /*
3057            * Quick sanity check..
3058            * Since a hook holds a reference on it's node, once we know
3059            * that the peer is still connected (even if invalid,) we know
3060            * that the peer node is present, though maybe invalid.
3061            */
3062           if ((hook == NULL) ||
3063               NG_HOOK_NOT_VALID(hook) ||
3064               NG_HOOK_NOT_VALID(peer = NG_HOOK_PEER(hook)) ||
3065               NG_NODE_NOT_VALID(peernode = NG_PEER_NODE(hook))) {
3066                     NG_FREE_ITEM(item);
3067                     TRAP_ERROR();
3068                     return (ENETDOWN);
3069           }
3070 
3071           /*
3072            * Transfer our interest to the other (peer) end.
3073            */
3074           NG_HOOK_REF(peer);
3075           NG_NODE_REF(peernode);
3076           NGI_SET_HOOK(item, peer);
3077           NGI_SET_NODE(item, peernode);
3078           SET_RETADDR(item, here, retaddr);
3079           return (0);
3080 }
3081 
3082 int
ng_address_path(node_p here,item_p item,char * address,ng_ID_t retaddr)3083 ng_address_path(node_p here, item_p item, char *address, ng_ID_t retaddr)
3084 {
3085           node_p    dest = NULL;
3086           hook_p    hook = NULL;
3087           int       error;
3088 
3089           ITEM_DEBUG_CHECKS;
3090           /*
3091            * Note that ng_path2noderef increments the reference count
3092            * on the node for us if it finds one. So we don't have to.
3093            */
3094           error = ng_path2noderef(here, address, &dest, &hook);
3095           if (error) {
3096                     NG_FREE_ITEM(item);
3097                     return (error);
3098           }
3099           NGI_SET_NODE(item, dest);
3100           if ( hook) {
3101                     NG_HOOK_REF(hook);  /* don't let it go while on the queue */
3102                     NGI_SET_HOOK(item, hook);
3103           }
3104           SET_RETADDR(item, here, retaddr);
3105           return (0);
3106 }
3107 
3108 int
ng_address_ID(node_p here,item_p item,ng_ID_t ID,ng_ID_t retaddr)3109 ng_address_ID(node_p here, item_p item, ng_ID_t ID, ng_ID_t retaddr)
3110 {
3111           node_p dest;
3112 
3113           ITEM_DEBUG_CHECKS;
3114           /*
3115            * Find the target node.
3116            */
3117           dest = ng_ID2noderef(ID); /* GETS REFERENCE! */
3118           if (dest == NULL) {
3119                     NG_FREE_ITEM(item);
3120                     TRAP_ERROR();
3121                     return(EINVAL);
3122           }
3123           /* Fill out the contents */
3124           NGI_SET_NODE(item, dest);
3125           NGI_CLR_HOOK(item);
3126           SET_RETADDR(item, here, retaddr);
3127           return (0);
3128 }
3129 
3130 /*
3131  * special case to send a message to self (e.g. destroy node)
3132  * Possibly indicate an arrival hook too.
3133  * Useful for removing that hook :-)
3134  */
3135 item_p
ng_package_msg_self(node_p here,hook_p hook,struct ng_mesg * msg)3136 ng_package_msg_self(node_p here, hook_p hook, struct ng_mesg *msg)
3137 {
3138           item_p item;
3139 
3140           /*
3141            * Find the target node.
3142            * If there is a HOOK argument, then use that in preference
3143            * to the address.
3144            */
3145           if ((item = ng_alloc_item(NGQF_MESG, NG_NOFLAGS)) == NULL) {
3146                     NG_FREE_MSG(msg);
3147                     return (NULL);
3148           }
3149 
3150           /* Fill out the contents */
3151           item->el_flags |= NGQF_WRITER;
3152           NG_NODE_REF(here);
3153           NGI_SET_NODE(item, here);
3154           if (hook) {
3155                     NG_HOOK_REF(hook);
3156                     NGI_SET_HOOK(item, hook);
3157           }
3158           NGI_MSG(item) = msg;
3159           NGI_RETADDR(item) = ng_node2ID(here);
3160           return (item);
3161 }
3162 
3163 /*
3164  * Send ng_item_fn function call to the specified node.
3165  */
3166 
3167 int
ng_send_fn(node_p node,hook_p hook,ng_item_fn * fn,void * arg1,int arg2)3168 ng_send_fn(node_p node, hook_p hook, ng_item_fn *fn, void * arg1, int arg2)
3169 {
3170           return ng_send_fn1(node, hook, fn, arg1, arg2, NG_NOFLAGS);
3171 }
3172 
3173 int
ng_send_fn1(node_p node,hook_p hook,ng_item_fn * fn,void * arg1,int arg2,int flags)3174 ng_send_fn1(node_p node, hook_p hook, ng_item_fn *fn, void * arg1, int arg2,
3175           int flags)
3176 {
3177           item_p item;
3178 
3179           if ((item = ng_alloc_item(NGQF_FN, flags)) == NULL) {
3180                     return (ENOMEM);
3181           }
3182           item->el_flags |= NGQF_WRITER;
3183           NG_NODE_REF(node); /* and one for the item */
3184           NGI_SET_NODE(item, node);
3185           if (hook) {
3186                     NG_HOOK_REF(hook);
3187                     NGI_SET_HOOK(item, hook);
3188           }
3189           NGI_FN(item) = fn;
3190           NGI_ARG1(item) = arg1;
3191           NGI_ARG2(item) = arg2;
3192           return(ng_snd_item(item, flags));
3193 }
3194 
3195 /*
3196  * Send ng_item_fn2 function call to the specified node.
3197  *
3198  * If NG_REUSE_ITEM flag is set, no new item will be allocated,
3199  * pitem will be used instead.
3200  */
3201 int
ng_send_fn2(node_p node,hook_p hook,item_p pitem,ng_item_fn2 * fn,void * arg1,int arg2,int flags)3202 ng_send_fn2(node_p node, hook_p hook, item_p pitem, ng_item_fn2 *fn, void *arg1,
3203           int arg2, int flags)
3204 {
3205           item_p item;
3206 
3207           KASSERT((pitem != NULL || (flags & NG_REUSE_ITEM) == 0),
3208               ("%s: NG_REUSE_ITEM but no pitem", __func__));
3209 
3210           /*
3211            * Allocate a new item if no supplied or
3212            * if we can't use supplied one.
3213            */
3214           if (pitem == NULL || (flags & NG_REUSE_ITEM) == 0) {
3215                     if ((item = ng_alloc_item(NGQF_FN2, flags)) == NULL)
3216                               return (ENOMEM);
3217           } else {
3218                     if ((item = ng_realloc_item(pitem, NGQF_FN2, flags)) == NULL)
3219                               return (ENOMEM);
3220           }
3221 
3222           item->el_flags = (item->el_flags & ~NGQF_RW) | NGQF_WRITER;
3223           NG_NODE_REF(node); /* and one for the item */
3224           NGI_SET_NODE(item, node);
3225           if (hook) {
3226                     NG_HOOK_REF(hook);
3227                     NGI_SET_HOOK(item, hook);
3228           }
3229           NGI_FN2(item) = fn;
3230           NGI_ARG1(item) = arg1;
3231           NGI_ARG2(item) = arg2;
3232           return(ng_snd_item(item, flags));
3233 }
3234 
3235 /*
3236  * Official timeout routines for Netgraph nodes.
3237  */
3238 static void
ng_callout_trampoline(void * arg)3239 ng_callout_trampoline(void *arg)
3240 {
3241           item_p item = arg;
3242 
3243           ng_snd_item(item, 0);
3244 }
3245 
3246 
3247 int
ng_callout(struct callout * c,node_p node,hook_p hook,int ticks,ng_item_fn * fn,void * arg1,int arg2)3248 ng_callout(struct callout *c, node_p node, hook_p hook, int ticks,
3249     ng_item_fn *fn, void * arg1, int arg2)
3250 {
3251           item_p item, oitem;
3252 
3253           if ((item = ng_alloc_item(NGQF_FN, NG_NOFLAGS)) == NULL)
3254                     return (ENOMEM);
3255 
3256           item->el_flags |= NGQF_WRITER;
3257           NG_NODE_REF(node);            /* and one for the item */
3258           NGI_SET_NODE(item, node);
3259           if (hook) {
3260                     NG_HOOK_REF(hook);
3261                     NGI_SET_HOOK(item, hook);
3262           }
3263           NGI_FN(item) = fn;
3264           NGI_ARG1(item) = arg1;
3265           NGI_ARG2(item) = arg2;
3266           oitem = callout_arg(c);
3267           callout_reset(c, ticks, &ng_callout_trampoline, item);
3268           return (0);
3269 }
3270 
3271 /* A special modified version of untimeout() */
3272 int
ng_uncallout(struct callout * c,node_p node)3273 ng_uncallout(struct callout *c, node_p node)
3274 {
3275           item_p item;
3276           int rval;
3277 
3278           KASSERT(c != NULL, ("ng_uncallout: NULL callout"));
3279           KASSERT(node != NULL, ("ng_uncallout: NULL node"));
3280 
3281           rval = callout_stop(c);
3282           item = callout_arg(c);
3283           /* Do an extra check */
3284           if ((rval > 0) && (callout_func(c) == &ng_callout_trampoline) &&
3285               (NGI_NODE(item) == node)) {
3286                     /*
3287                      * We successfully removed it from the queue before it ran
3288                      * So now we need to unreference everything that was
3289                      * given extra references. (NG_FREE_ITEM does this).
3290                      */
3291                     NG_FREE_ITEM(item);
3292           }
3293           callout_set_arg(c, NULL);
3294 
3295           return (rval);
3296 }
3297 
3298 /*
3299  * Set the address, if none given, give the node here.
3300  */
3301 void
ng_replace_retaddr(node_p here,item_p item,ng_ID_t retaddr)3302 ng_replace_retaddr(node_p here, item_p item, ng_ID_t retaddr)
3303 {
3304           if (retaddr) {
3305                     NGI_RETADDR(item) = retaddr;
3306           } else {
3307                     /*
3308                      * The old return address should be ok.
3309                      * If there isn't one, use the address here.
3310                      */
3311                     NGI_RETADDR(item) = ng_node2ID(here);
3312           }
3313 }
3314 
3315 static boolean_t
bzero_ctor(void * obj,void * private,int ocflags)3316 bzero_ctor(void *obj, void *private, int ocflags)
3317 {
3318           struct ng_item *i = obj;
3319 
3320           bzero(i, sizeof(struct ng_item));
3321           return(TRUE);
3322 }
3323 
3324 #define TESTING
3325 #ifdef TESTING
3326 /* just test all the macros */
3327 void
3328 ng_macro_test(item_p item);
3329 void
ng_macro_test(item_p item)3330 ng_macro_test(item_p item)
3331 {
3332           node_p node = NULL;
3333           hook_p hook = NULL;
3334           struct mbuf *m;
3335           struct ng_mesg *msg;
3336           ng_ID_t retaddr;
3337           int       error;
3338 
3339           NGI_GET_M(item, m);
3340           NGI_GET_MSG(item, msg);
3341           retaddr = NGI_RETADDR(item);
3342           NG_SEND_DATA(error, hook, m, NULL);
3343           NG_SEND_DATA_ONLY(error, hook, m);
3344           NG_FWD_NEW_DATA(error, item, hook, m);
3345           NG_FWD_ITEM_HOOK(error, item, hook);
3346           NG_SEND_MSG_HOOK(error, node, msg, hook, retaddr);
3347           NG_SEND_MSG_ID(error, node, msg, retaddr, retaddr);
3348           NG_SEND_MSG_PATH(error, node, msg, ".:", retaddr);
3349           NG_FWD_MSG_HOOK(error, node, item, hook, retaddr);
3350 }
3351 #endif /* TESTING */
3352 
3353