1
2 /*
3 * ng_base.c
4 *
5 * Copyright (c) 1996-1999 Whistle Communications, Inc.
6 * All rights reserved.
7 *
8 * Subject to the following obligations and disclaimer of warranty, use and
9 * redistribution of this software, in source or object code forms, with or
10 * without modifications are expressly permitted by Whistle Communications;
11 * provided, however, that:
12 * 1. Any and all reproductions of the source or object code must include the
13 * copyright notice above and the following disclaimer of warranties; and
14 * 2. No rights are granted, in any manner or form, to use Whistle
15 * Communications, Inc. trademarks, including the mark "WHISTLE
16 * COMMUNICATIONS" on advertising, endorsements, or otherwise except as
17 * such appears in the above copyright notice or in the software.
18 *
19 * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
20 * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
21 * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
22 * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
23 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
24 * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
25 * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
26 * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
27 * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
28 * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
29 * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
30 * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
31 * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
32 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
33 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
34 * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
35 * OF SUCH DAMAGE.
36 *
37 * Authors: Julian Elischer <julian@freebsd.org>
38 * Archie Cobbs <archie@freebsd.org>
39 *
40 * $FreeBSD$
41 * $Whistle: ng_base.c,v 1.39 1999/01/28 23:54:53 julian Exp $
42 */
43
44 /*
45 * This file implements the base netgraph code.
46 */
47
48 #include <sys/param.h>
49 #include <sys/systm.h>
50 #include <sys/errno.h>
51 #include <sys/kernel.h>
52 #include <sys/malloc.h>
53 #include <sys/syslog.h>
54 #include <sys/linker.h>
55 #include <sys/queue.h>
56 #include <sys/mbuf.h>
57 #include <sys/ctype.h>
58 #include <machine/limits.h>
59
60 #include <net/netisr.h>
61
62 #include <netgraph/ng_message.h>
63 #include <netgraph/netgraph.h>
64 #include <netgraph/ng_parse.h>
65
66 /* List of all nodes */
67 static LIST_HEAD(, ng_node) nodelist;
68
69 /* List of installed types */
70 static LIST_HEAD(, ng_type) typelist;
71
72 /* Hash releted definitions */
73 #define ID_HASH_SIZE 32 /* most systems wont need even this many */
74 static LIST_HEAD(, ng_node) ID_hash[ID_HASH_SIZE];
75 /* Don't nead to initialise them because it's a LIST */
76
77 /* Internal functions */
78 static int ng_add_hook(node_p node, const char *name, hook_p * hookp);
79 static int ng_connect(hook_p hook1, hook_p hook2);
80 static void ng_disconnect_hook(hook_p hook);
81 static int ng_generic_msg(node_p here, struct ng_mesg *msg,
82 const char *retaddr, struct ng_mesg ** resp);
83 static ng_ID_t ng_decodeidname(const char *name);
84 static int ngb_mod_event(module_t mod, int event, void *data);
85 static void ngintr(void);
86
87 /* Our own netgraph malloc type */
88 MALLOC_DEFINE(M_NETGRAPH, "netgraph", "netgraph structures and ctrl messages");
89
90 /* Set this to Debugger("X") to catch all errors as they occur */
91 #ifndef TRAP_ERROR
92 #define TRAP_ERROR
93 #endif
94
95 static ng_ID_t nextID = 1;
96
97 #ifdef INVARIANTS
98 #define CHECK_DATA_MBUF(m) do { \
99 struct mbuf *n; \
100 int total; \
101 \
102 if (((m)->m_flags & M_PKTHDR) == 0) \
103 panic("%s: !PKTHDR", __FUNCTION__); \
104 for (total = 0, n = (m); n != NULL; n = n->m_next) \
105 total += n->m_len; \
106 if ((m)->m_pkthdr.len != total) { \
107 panic("%s: %d != %d", \
108 __FUNCTION__, (m)->m_pkthdr.len, total); \
109 } \
110 } while (0)
111 #else
112 #define CHECK_DATA_MBUF(m)
113 #endif
114
115
116 /************************************************************************
117 Parse type definitions for generic messages
118 ************************************************************************/
119
120 /* Handy structure parse type defining macro */
121 #define DEFINE_PARSE_STRUCT_TYPE(lo, up, args) \
122 static const struct ng_parse_struct_info \
123 ng_ ## lo ## _type_info = NG_GENERIC_ ## up ## _INFO args; \
124 static const struct ng_parse_type ng_generic_ ## lo ## _type = { \
125 &ng_parse_struct_type, \
126 &ng_ ## lo ## _type_info \
127 }
128
129 DEFINE_PARSE_STRUCT_TYPE(mkpeer, MKPEER, ());
130 DEFINE_PARSE_STRUCT_TYPE(connect, CONNECT, ());
131 DEFINE_PARSE_STRUCT_TYPE(name, NAME, ());
132 DEFINE_PARSE_STRUCT_TYPE(rmhook, RMHOOK, ());
133 DEFINE_PARSE_STRUCT_TYPE(nodeinfo, NODEINFO, ());
134 DEFINE_PARSE_STRUCT_TYPE(typeinfo, TYPEINFO, ());
135 DEFINE_PARSE_STRUCT_TYPE(linkinfo, LINKINFO, (&ng_generic_nodeinfo_type));
136
137 /* Get length of an array when the length is stored as a 32 bit
138 value immediately preceeding the array -- as with struct namelist
139 and struct typelist. */
140 static int
141 ng_generic_list_getLength(const struct ng_parse_type *type,
142 const u_char *start, const u_char *buf)
143 {
144 return *((const u_int32_t *)(buf - 4));
145 }
146
147 /* Get length of the array of struct linkinfo inside a struct hooklist */
148 static int
149 ng_generic_linkinfo_getLength(const struct ng_parse_type *type,
150 const u_char *start, const u_char *buf)
151 {
152 const struct hooklist *hl = (const struct hooklist *)start;
153
154 return hl->nodeinfo.hooks;
155 }
156
157 /* Array type for a variable length array of struct namelist */
158 static const struct ng_parse_array_info ng_nodeinfoarray_type_info = {
159 &ng_generic_nodeinfo_type,
160 &ng_generic_list_getLength
161 };
162 static const struct ng_parse_type ng_generic_nodeinfoarray_type = {
163 &ng_parse_array_type,
164 &ng_nodeinfoarray_type_info
165 };
166
167 /* Array type for a variable length array of struct typelist */
168 static const struct ng_parse_array_info ng_typeinfoarray_type_info = {
169 &ng_generic_typeinfo_type,
170 &ng_generic_list_getLength
171 };
172 static const struct ng_parse_type ng_generic_typeinfoarray_type = {
173 &ng_parse_array_type,
174 &ng_typeinfoarray_type_info
175 };
176
177 /* Array type for array of struct linkinfo in struct hooklist */
178 static const struct ng_parse_array_info ng_generic_linkinfo_array_type_info = {
179 &ng_generic_linkinfo_type,
180 &ng_generic_linkinfo_getLength
181 };
182 static const struct ng_parse_type ng_generic_linkinfo_array_type = {
183 &ng_parse_array_type,
184 &ng_generic_linkinfo_array_type_info
185 };
186
187 DEFINE_PARSE_STRUCT_TYPE(typelist, TYPELIST, (&ng_generic_nodeinfoarray_type));
188 DEFINE_PARSE_STRUCT_TYPE(hooklist, HOOKLIST,
189 (&ng_generic_nodeinfo_type, &ng_generic_linkinfo_array_type));
190 DEFINE_PARSE_STRUCT_TYPE(listnodes, LISTNODES,
191 (&ng_generic_nodeinfoarray_type));
192
193 /* List of commands and how to convert arguments to/from ASCII */
194 static const struct ng_cmdlist ng_generic_cmds[] = {
195 {
196 NGM_GENERIC_COOKIE,
197 NGM_SHUTDOWN,
198 "shutdown",
199 NULL,
200 NULL
201 },
202 {
203 NGM_GENERIC_COOKIE,
204 NGM_MKPEER,
205 "mkpeer",
206 &ng_generic_mkpeer_type,
207 NULL
208 },
209 {
210 NGM_GENERIC_COOKIE,
211 NGM_CONNECT,
212 "connect",
213 &ng_generic_connect_type,
214 NULL
215 },
216 {
217 NGM_GENERIC_COOKIE,
218 NGM_NAME,
219 "name",
220 &ng_generic_name_type,
221 NULL
222 },
223 {
224 NGM_GENERIC_COOKIE,
225 NGM_RMHOOK,
226 "rmhook",
227 &ng_generic_rmhook_type,
228 NULL
229 },
230 {
231 NGM_GENERIC_COOKIE,
232 NGM_NODEINFO,
233 "nodeinfo",
234 NULL,
235 &ng_generic_nodeinfo_type
236 },
237 {
238 NGM_GENERIC_COOKIE,
239 NGM_LISTHOOKS,
240 "listhooks",
241 NULL,
242 &ng_generic_hooklist_type
243 },
244 {
245 NGM_GENERIC_COOKIE,
246 NGM_LISTNAMES,
247 "listnames",
248 NULL,
249 &ng_generic_listnodes_type /* same as NGM_LISTNODES */
250 },
251 {
252 NGM_GENERIC_COOKIE,
253 NGM_LISTNODES,
254 "listnodes",
255 NULL,
256 &ng_generic_listnodes_type
257 },
258 {
259 NGM_GENERIC_COOKIE,
260 NGM_LISTTYPES,
261 "listtypes",
262 NULL,
263 &ng_generic_typeinfo_type
264 },
265 {
266 NGM_GENERIC_COOKIE,
267 NGM_TEXT_STATUS,
268 "textstatus",
269 NULL,
270 &ng_parse_string_type
271 },
272 {
273 NGM_GENERIC_COOKIE,
274 NGM_ASCII2BINARY,
275 "ascii2binary",
276 &ng_parse_ng_mesg_type,
277 &ng_parse_ng_mesg_type
278 },
279 {
280 NGM_GENERIC_COOKIE,
281 NGM_BINARY2ASCII,
282 "binary2ascii",
283 &ng_parse_ng_mesg_type,
284 &ng_parse_ng_mesg_type
285 },
286 { 0 }
287 };
288
289 /************************************************************************
290 Node routines
291 ************************************************************************/
292
293 /*
294 * Instantiate a node of the requested type
295 */
296 int
297 ng_make_node(const char *typename, node_p *nodepp)
298 {
299 struct ng_type *type;
300
301 /* Check that the type makes sense */
302 if (typename == NULL) {
303 TRAP_ERROR;
304 return (EINVAL);
305 }
306
307 /* Locate the node type */
308 if ((type = ng_findtype(typename)) == NULL) {
309 char *path, filename[NG_TYPELEN + 4];
310 linker_file_t lf;
311 int error;
312
313 /* Not found, try to load it as a loadable module */
314 snprintf(filename, sizeof(filename), "ng_%s.ko", typename);
315 if ((path = linker_search_path(filename)) == NULL)
316 return (ENXIO);
317 error = linker_load_file(path, &lf);
318 FREE(path, M_LINKER);
319 if (error != 0)
320 return (error);
321 lf->userrefs++; /* pretend loaded by the syscall */
322
323 /* Try again, as now the type should have linked itself in */
324 if ((type = ng_findtype(typename)) == NULL)
325 return (ENXIO);
326 }
327
328 /* Call the constructor */
329 if (type->constructor != NULL)
330 return ((*type->constructor)(nodepp));
331 else
332 return (ng_make_node_common(type, nodepp));
333 }
334
335 /*
336 * Generic node creation. Called by node constructors.
337 * The returned node has a reference count of 1.
338 */
339 int
340 ng_make_node_common(struct ng_type *type, node_p *nodepp)
341 {
342 node_p node;
343
344 /* Require the node type to have been already installed */
345 if (ng_findtype(type->name) == NULL) {
346 TRAP_ERROR;
347 return (EINVAL);
348 }
349
350 /* Make a node and try attach it to the type */
351 MALLOC(node, node_p, sizeof(*node), M_NETGRAPH, M_WAITOK);
352 if (node == NULL) {
353 TRAP_ERROR;
354 return (ENOMEM);
355 }
356 bzero(node, sizeof(*node));
357 node->type = type;
358 node->refs++; /* note reference */
359 type->refs++;
360
361 /* Link us into the node linked list */
362 LIST_INSERT_HEAD(&nodelist, node, nodes);
363
364 /* Initialize hook list for new node */
365 LIST_INIT(&node->hooks);
366
367 /* get an ID and put us in the hash chain */
368 node->ID = nextID++; /* 137 per second for 1 year before wrap */
369 LIST_INSERT_HEAD(&ID_hash[node->ID % ID_HASH_SIZE], node, idnodes);
370
371 /* Done */
372 *nodepp = node;
373 return (0);
374 }
375
376 /*
377 * Forceably start the shutdown process on a node. Either call
378 * it's shutdown method, or do the default shutdown if there is
379 * no type-specific method.
380 *
381 * Persistent nodes must have a type-specific method which
382 * resets the NG_INVALID flag.
383 */
384 void
385 ng_rmnode(node_p node)
386 {
387 /* Check if it's already shutting down */
388 if ((node->flags & NG_INVALID) != 0)
389 return;
390
391 /* Add an extra reference so it doesn't go away during this */
392 node->refs++;
393
394 /* Mark it invalid so any newcomers know not to try use it */
395 node->flags |= NG_INVALID;
396
397 /* Ask the type if it has anything to do in this case */
398 if (node->type && node->type->shutdown)
399 (*node->type->shutdown)(node);
400 else { /* do the default thing */
401 ng_unname(node);
402 ng_cutlinks(node);
403 ng_unref(node);
404 }
405
406 /* Remove extra reference, possibly the last */
407 ng_unref(node);
408 }
409
410 /*
411 * Called by the destructor to remove any STANDARD external references
412 */
413 void
414 ng_cutlinks(node_p node)
415 {
416 hook_p hook;
417
418 /* Make sure that this is set to stop infinite loops */
419 node->flags |= NG_INVALID;
420
421 /* If we have sleepers, wake them up; they'll see NG_INVALID */
422 if (node->sleepers)
423 wakeup(node);
424
425 /* Notify all remaining connected nodes to disconnect */
426 while ((hook = LIST_FIRST(&node->hooks)) != NULL)
427 ng_destroy_hook(hook);
428 }
429
430 /*
431 * Remove a reference to the node, possibly the last
432 */
433 void
434 ng_unref(node_p node)
435 {
436 int s;
437
438 s = splhigh();
439 if (--node->refs <= 0) {
440 node->type->refs--;
441 LIST_REMOVE(node, nodes);
442 LIST_REMOVE(node, idnodes);
443 FREE(node, M_NETGRAPH);
444 }
445 splx(s);
446 }
447
448 /*
449 * Wait for a node to come ready. Returns a node with a reference count;
450 * don't forget to drop it when we are done with it using ng_release_node().
451 */
452 int
453 ng_wait_node(node_p node, char *msg)
454 {
455 int s, error = 0;
456
457 if (msg == NULL)
458 msg = "netgraph";
459 s = splnet();
460 node->sleepers++;
461 node->refs++; /* the sleeping process counts as a reference */
462 while ((node->flags & (NG_BUSY | NG_INVALID)) == NG_BUSY)
463 error = tsleep(node, (PZERO + 1) | PCATCH, msg, 0);
464 node->sleepers--;
465 if (node->flags & NG_INVALID) {
466 TRAP_ERROR;
467 error = ENXIO;
468 } else {
469 KASSERT(node->refs > 1,
470 ("%s: refs=%d", __FUNCTION__, node->refs));
471 node->flags |= NG_BUSY;
472 }
473 splx(s);
474
475 /* Release the reference we had on it */
476 if (error != 0)
477 ng_unref(node);
478 return error;
479 }
480
481 /*
482 * Release a node acquired via ng_wait_node()
483 */
484 void
485 ng_release_node(node_p node)
486 {
487 /* Declare that we don't want it */
488 node->flags &= ~NG_BUSY;
489
490 /* If we have sleepers, then wake them up */
491 if (node->sleepers)
492 wakeup(node);
493
494 /* We also have a reference.. drop it too */
495 ng_unref(node);
496 }
497
498 /************************************************************************
499 Node ID handling
500 ************************************************************************/
501 static node_p
502 ng_ID2node(ng_ID_t ID)
503 {
504 node_p np;
505 LIST_FOREACH(np, &ID_hash[ID % ID_HASH_SIZE], idnodes) {
506 if (np->ID == ID)
507 break;
508 }
509 return(np);
510 }
511
512 ng_ID_t
513 ng_node2ID(node_p node)
514 {
515 return (node->ID);
516 }
517
518 /************************************************************************
519 Node name handling
520 ************************************************************************/
521
522 /*
523 * Assign a node a name. Once assigned, the name cannot be changed.
524 */
525 int
526 ng_name_node(node_p node, const char *name)
527 {
528 int i;
529
530 /* Check the name is valid */
531 for (i = 0; i < NG_NODELEN + 1; i++) {
532 if (name[i] == '\0' || name[i] == '.' || name[i] == ':')
533 break;
534 }
535 if (i == 0 || name[i] != '\0') {
536 TRAP_ERROR;
537 return (EINVAL);
538 }
539 if (ng_decodeidname(name) != 0) { /* valid IDs not allowed here */
540 TRAP_ERROR;
541 return (EINVAL);
542 }
543
544 /* Check the node isn't already named */
545 if (node->name != NULL) {
546 TRAP_ERROR;
547 return (EISCONN);
548 }
549
550 /* Check the name isn't already being used */
551 if (ng_findname(node, name) != NULL) {
552 TRAP_ERROR;
553 return (EADDRINUSE);
554 }
555
556 /* Allocate space and copy it */
557 MALLOC(node->name, char *, strlen(name) + 1, M_NETGRAPH, M_WAITOK);
558 if (node->name == NULL) {
559 TRAP_ERROR;
560 return (ENOMEM);
561 }
562 strcpy(node->name, name);
563
564 /* The name counts as a reference */
565 node->refs++;
566 return (0);
567 }
568
569 /*
570 * Find a node by absolute name. The name should NOT end with ':'
571 * The name "." means "this node" and "[xxx]" means "the node
572 * with ID (ie, at address) xxx".
573 *
574 * Returns the node if found, else NULL.
575 */
576 node_p
577 ng_findname(node_p this, const char *name)
578 {
579 node_p node;
580 ng_ID_t temp;
581
582 /* "." means "this node" */
583 if (strcmp(name, ".") == 0)
584 return(this);
585
586 /* Check for name-by-ID */
587 if ((temp = ng_decodeidname(name)) != 0) {
588 return (ng_ID2node(temp));
589 }
590
591 /* Find node by name */
592 LIST_FOREACH(node, &nodelist, nodes) {
593 if (node->name != NULL && strcmp(node->name, name) == 0)
594 break;
595 }
596 return (node);
597 }
598
599 /*
600 * Decode a ID name, eg. "[f03034de]". Returns 0 if the
601 * string is not valid, otherwise returns the value.
602 */
603 static ng_ID_t
604 ng_decodeidname(const char *name)
605 {
606 const int len = strlen(name);
607 char *eptr;
608 u_long val;
609
610 /* Check for proper length, brackets, no leading junk */
611 if (len < 3 || name[0] != '[' || name[len - 1] != ']'
612 || !isxdigit(name[1]))
613 return (0);
614
615 /* Decode number */
616 val = strtoul(name + 1, &eptr, 16);
617 if (eptr - name != len - 1 || val == ULONG_MAX || val == 0)
618 return ((ng_ID_t)0);
619 return (ng_ID_t)val;
620 }
621
622 /*
623 * Remove a name from a node. This should only be called
624 * when shutting down and removing the node.
625 */
626 void
627 ng_unname(node_p node)
628 {
629 if (node->name) {
630 FREE(node->name, M_NETGRAPH);
631 node->name = NULL;
632 ng_unref(node);
633 }
634 }
635
636 /************************************************************************
637 Hook routines
638
639 Names are not optional. Hooks are always connected, except for a
640 brief moment within these routines.
641
642 ************************************************************************/
643
644 /*
645 * Remove a hook reference
646 */
647 static void
648 ng_unref_hook(hook_p hook)
649 {
650 int s;
651
652 s = splhigh();
653 if (--hook->refs == 0)
654 FREE(hook, M_NETGRAPH);
655 splx(s);
656 }
657
658 /*
659 * Add an unconnected hook to a node. Only used internally.
660 */
661 static int
662 ng_add_hook(node_p node, const char *name, hook_p *hookp)
663 {
664 hook_p hook;
665 int error = 0;
666
667 /* Check that the given name is good */
668 if (name == NULL) {
669 TRAP_ERROR;
670 return (EINVAL);
671 }
672 if (ng_findhook(node, name) != NULL) {
673 TRAP_ERROR;
674 return (EEXIST);
675 }
676
677 /* Allocate the hook and link it up */
678 MALLOC(hook, hook_p, sizeof(*hook), M_NETGRAPH, M_WAITOK);
679 if (hook == NULL) {
680 TRAP_ERROR;
681 return (ENOMEM);
682 }
683 bzero(hook, sizeof(*hook));
684 hook->refs = 1;
685 hook->flags = HK_INVALID;
686 hook->node = node;
687 node->refs++; /* each hook counts as a reference */
688
689 /* Check if the node type code has something to say about it */
690 if (node->type->newhook != NULL)
691 if ((error = (*node->type->newhook)(node, hook, name)) != 0)
692 goto fail;
693
694 /*
695 * The 'type' agrees so far, so go ahead and link it in.
696 * We'll ask again later when we actually connect the hooks.
697 */
698 LIST_INSERT_HEAD(&node->hooks, hook, hooks);
699 node->numhooks++;
700
701 /* Set hook name */
702 MALLOC(hook->name, char *, strlen(name) + 1, M_NETGRAPH, M_WAITOK);
703 if (hook->name == NULL) {
704 error = ENOMEM;
705 LIST_REMOVE(hook, hooks);
706 node->numhooks--;
707 fail:
708 hook->node = NULL;
709 ng_unref(node);
710 ng_unref_hook(hook); /* this frees the hook */
711 return (error);
712 }
713 strcpy(hook->name, name);
714 if (hookp)
715 *hookp = hook;
716 return (error);
717 }
718
719 /*
720 * Connect a pair of hooks. Only used internally.
721 */
722 static int
723 ng_connect(hook_p hook1, hook_p hook2)
724 {
725 int error;
726
727 hook1->peer = hook2;
728 hook2->peer = hook1;
729
730 /* Give each node the opportunity to veto the impending connection */
731 if (hook1->node->type->connect) {
732 if ((error = (*hook1->node->type->connect) (hook1))) {
733 ng_destroy_hook(hook1); /* also zaps hook2 */
734 return (error);
735 }
736 }
737 if (hook2->node->type->connect) {
738 if ((error = (*hook2->node->type->connect) (hook2))) {
739 ng_destroy_hook(hook2); /* also zaps hook1 */
740 return (error);
741 }
742 }
743 hook1->flags &= ~HK_INVALID;
744 hook2->flags &= ~HK_INVALID;
745 return (0);
746 }
747
748 /*
749 * Find a hook
750 *
751 * Node types may supply their own optimized routines for finding
752 * hooks. If none is supplied, we just do a linear search.
753 */
754 hook_p
755 ng_findhook(node_p node, const char *name)
756 {
757 hook_p hook;
758
759 if (node->type->findhook != NULL)
760 return (*node->type->findhook)(node, name);
761 LIST_FOREACH(hook, &node->hooks, hooks) {
762 if (hook->name != NULL && strcmp(hook->name, name) == 0)
763 return (hook);
764 }
765 return (NULL);
766 }
767
768 /*
769 * Destroy a hook
770 *
771 * As hooks are always attached, this really destroys two hooks.
772 * The one given, and the one attached to it. Disconnect the hooks
773 * from each other first.
774 */
775 void
776 ng_destroy_hook(hook_p hook)
777 {
778 hook_p peer = hook->peer;
779
780 hook->flags |= HK_INVALID; /* as soon as possible */
781 if (peer) {
782 peer->flags |= HK_INVALID; /* as soon as possible */
783 hook->peer = NULL;
784 peer->peer = NULL;
785 ng_disconnect_hook(peer);
786 }
787 ng_disconnect_hook(hook);
788 }
789
790 /*
791 * Notify the node of the hook's demise. This may result in more actions
792 * (e.g. shutdown) but we don't do that ourselves and don't know what
793 * happens there. If there is no appropriate handler, then just remove it
794 * (and decrement the reference count of it's node which in turn might
795 * make something happen).
796 */
797 static void
798 ng_disconnect_hook(hook_p hook)
799 {
800 node_p node = hook->node;
801
802 /*
803 * Remove the hook from the node's list to avoid possible recursion
804 * in case the disconnection results in node shutdown.
805 */
806 LIST_REMOVE(hook, hooks);
807 node->numhooks--;
808 if (node->type->disconnect) {
809 /*
810 * The type handler may elect to destroy the peer so don't
811 * trust its existance after this point.
812 */
813 (*node->type->disconnect) (hook);
814 }
815 ng_unref(node); /* might be the last reference */
816 if (hook->name)
817 FREE(hook->name, M_NETGRAPH);
818 hook->node = NULL; /* may still be referenced elsewhere */
819 ng_unref_hook(hook);
820 }
821
822 /*
823 * Take two hooks on a node and merge the connection so that the given node
824 * is effectively bypassed.
825 */
826 int
827 ng_bypass(hook_p hook1, hook_p hook2)
828 {
829 if (hook1->node != hook2->node)
830 return (EINVAL);
831 hook1->peer->peer = hook2->peer;
832 hook2->peer->peer = hook1->peer;
833
834 /* XXX If we ever cache methods on hooks update them as well */
835 hook1->peer = NULL;
836 hook2->peer = NULL;
837 ng_destroy_hook(hook1);
838 ng_destroy_hook(hook2);
839 return (0);
840 }
841
842 /*
843 * Install a new netgraph type
844 */
845 int
846 ng_newtype(struct ng_type *tp)
847 {
848 const size_t namelen = strlen(tp->name);
849
850 /* Check version and type name fields */
851 if (tp->version != NG_VERSION || namelen == 0 || namelen > NG_TYPELEN) {
852 TRAP_ERROR;
853 return (EINVAL);
854 }
855
856 /* Check for name collision */
857 if (ng_findtype(tp->name) != NULL) {
858 TRAP_ERROR;
859 return (EEXIST);
860 }
861
862 /* Link in new type */
863 LIST_INSERT_HEAD(&typelist, tp, types);
864 tp->refs = 0;
865 return (0);
866 }
867
868 /*
869 * Look for a type of the name given
870 */
871 struct ng_type *
872 ng_findtype(const char *typename)
873 {
874 struct ng_type *type;
875
876 LIST_FOREACH(type, &typelist, types) {
877 if (strcmp(type->name, typename) == 0)
878 break;
879 }
880 return (type);
881 }
882
883
884 /************************************************************************
885 Composite routines
886 ************************************************************************/
887
888 /*
889 * Make a peer and connect. The order is arranged to minimise
890 * the work needed to back out in case of error.
891 */
892 int
893 ng_mkpeer(node_p node, const char *name, const char *name2, char *type)
894 {
895 node_p node2;
896 hook_p hook;
897 hook_p hook2;
898 int error;
899
900 if ((error = ng_add_hook(node, name, &hook)))
901 return (error);
902 if ((error = ng_make_node(type, &node2))) {
903 ng_destroy_hook(hook);
904 return (error);
905 }
906 if ((error = ng_add_hook(node2, name2, &hook2))) {
907 ng_rmnode(node2);
908 ng_destroy_hook(hook);
909 return (error);
910 }
911
912 /*
913 * Actually link the two hooks together.. on failure they are
914 * destroyed so we don't have to do that here.
915 */
916 if ((error = ng_connect(hook, hook2)))
917 ng_rmnode(node2);
918 return (error);
919 }
920
921 /*
922 * Connect two nodes using the specified hooks
923 */
924 int
925 ng_con_nodes(node_p node, const char *name, node_p node2, const char *name2)
926 {
927 int error;
928 hook_p hook;
929 hook_p hook2;
930
931 if ((error = ng_add_hook(node, name, &hook)))
932 return (error);
933 if ((error = ng_add_hook(node2, name2, &hook2))) {
934 ng_destroy_hook(hook);
935 return (error);
936 }
937 return (ng_connect(hook, hook2));
938 }
939
940 /*
941 * Parse and verify a string of the form: <NODE:><PATH>
942 *
943 * Such a string can refer to a specific node or a specific hook
944 * on a specific node, depending on how you look at it. In the
945 * latter case, the PATH component must not end in a dot.
946 *
947 * Both <NODE:> and <PATH> are optional. The <PATH> is a string
948 * of hook names separated by dots. This breaks out the original
949 * string, setting *nodep to "NODE" (or NULL if none) and *pathp
950 * to "PATH" (or NULL if degenerate). Also, *hookp will point to
951 * the final hook component of <PATH>, if any, otherwise NULL.
952 *
953 * This returns -1 if the path is malformed. The char ** are optional.
954 */
955
956 int
957 ng_path_parse(char *addr, char **nodep, char **pathp, char **hookp)
958 {
959 char *node, *path, *hook;
960 int k;
961
962 /*
963 * Extract absolute NODE, if any
964 */
965 for (path = addr; *path && *path != ':'; path++);
966 if (*path) {
967 node = addr; /* Here's the NODE */
968 *path++ = '\0'; /* Here's the PATH */
969
970 /* Node name must not be empty */
971 if (!*node)
972 return -1;
973
974 /* A name of "." is OK; otherwise '.' not allowed */
975 if (strcmp(node, ".") != 0) {
976 for (k = 0; node[k]; k++)
977 if (node[k] == '.')
978 return -1;
979 }
980 } else {
981 node = NULL; /* No absolute NODE */
982 path = addr; /* Here's the PATH */
983 }
984
985 /* Snoop for illegal characters in PATH */
986 for (k = 0; path[k]; k++)
987 if (path[k] == ':')
988 return -1;
989
990 /* Check for no repeated dots in PATH */
991 for (k = 0; path[k]; k++)
992 if (path[k] == '.' && path[k + 1] == '.')
993 return -1;
994
995 /* Remove extra (degenerate) dots from beginning or end of PATH */
996 if (path[0] == '.')
997 path++;
998 if (*path && path[strlen(path) - 1] == '.')
999 path[strlen(path) - 1] = 0;
1000
1001 /* If PATH has a dot, then we're not talking about a hook */
1002 if (*path) {
1003 for (hook = path, k = 0; path[k]; k++)
1004 if (path[k] == '.') {
1005 hook = NULL;
1006 break;
1007 }
1008 } else
1009 path = hook = NULL;
1010
1011 /* Done */
1012 if (nodep)
1013 *nodep = node;
1014 if (pathp)
1015 *pathp = path;
1016 if (hookp)
1017 *hookp = hook;
1018 return (0);
1019 }
1020
1021 /*
1022 * Given a path, which may be absolute or relative, and a starting node,
1023 * return the destination node. Compute the "return address" if desired.
1024 */
1025 int
1026 ng_path2node(node_p here, const char *address, node_p *destp, char **rtnp)
1027 {
1028 const node_p start = here;
1029 char fullpath[NG_PATHLEN + 1];
1030 char *nodename, *path, pbuf[2];
1031 node_p node;
1032 char *cp;
1033
1034 /* Initialize */
1035 if (rtnp)
1036 *rtnp = NULL;
1037 if (destp == NULL)
1038 return EINVAL;
1039 *destp = NULL;
1040
1041 /* Make a writable copy of address for ng_path_parse() */
1042 strncpy(fullpath, address, sizeof(fullpath) - 1);
1043 fullpath[sizeof(fullpath) - 1] = '\0';
1044
1045 /* Parse out node and sequence of hooks */
1046 if (ng_path_parse(fullpath, &nodename, &path, NULL) < 0) {
1047 TRAP_ERROR;
1048 return EINVAL;
1049 }
1050 if (path == NULL) {
1051 pbuf[0] = '.'; /* Needs to be writable */
1052 pbuf[1] = '\0';
1053 path = pbuf;
1054 }
1055
1056 /* For an absolute address, jump to the starting node */
1057 if (nodename) {
1058 node = ng_findname(here, nodename);
1059 if (node == NULL) {
1060 TRAP_ERROR;
1061 return (ENOENT);
1062 }
1063 } else
1064 node = here;
1065
1066 /* Now follow the sequence of hooks */
1067 for (cp = path; node != NULL && *cp != '\0'; ) {
1068 hook_p hook;
1069 char *segment;
1070
1071 /*
1072 * Break out the next path segment. Replace the dot we just
1073 * found with a NUL; "cp" points to the next segment (or the
1074 * NUL at the end).
1075 */
1076 for (segment = cp; *cp != '\0'; cp++) {
1077 if (*cp == '.') {
1078 *cp++ = '\0';
1079 break;
1080 }
1081 }
1082
1083 /* Empty segment */
1084 if (*segment == '\0')
1085 continue;
1086
1087 /* We have a segment, so look for a hook by that name */
1088 hook = ng_findhook(node, segment);
1089
1090 /* Can't get there from here... */
1091 if (hook == NULL
1092 || hook->peer == NULL
1093 || (hook->flags & HK_INVALID) != 0) {
1094 TRAP_ERROR;
1095 return (ENOENT);
1096 }
1097
1098 /* Hop on over to the next node */
1099 node = hook->peer->node;
1100 }
1101
1102 /* If node somehow missing, fail here (probably this is not needed) */
1103 if (node == NULL) {
1104 TRAP_ERROR;
1105 return (ENXIO);
1106 }
1107
1108 /* Now compute return address, i.e., the path to the sender */
1109 if (rtnp != NULL) {
1110 MALLOC(*rtnp, char *, NG_NODELEN + 2, M_NETGRAPH, M_WAITOK);
1111 if (*rtnp == NULL) {
1112 TRAP_ERROR;
1113 return (ENOMEM);
1114 }
1115 if (start->name != NULL)
1116 sprintf(*rtnp, "%s:", start->name);
1117 else
1118 sprintf(*rtnp, "[%x]:", ng_node2ID(start));
1119 }
1120
1121 /* Done */
1122 *destp = node;
1123 return (0);
1124 }
1125
1126 /*
1127 * Call the appropriate message handler for the object.
1128 * It is up to the message handler to free the message.
1129 * If it's a generic message, handle it generically, otherwise
1130 * call the type's message handler (if it exists)
1131 * XXX (race). Remember that a queued message may reference a node
1132 * or hook that has just been invalidated. It will exist
1133 * as the queue code is holding a reference, but..
1134 */
1135
1136 #define CALL_MSG_HANDLER(error, node, msg, retaddr, resp) \
1137 do { \
1138 if((msg)->header.typecookie == NGM_GENERIC_COOKIE) { \
1139 (error) = ng_generic_msg((node), (msg), \
1140 (retaddr), (resp)); \
1141 } else { \
1142 if ((node)->type->rcvmsg != NULL) { \
1143 (error) = (*(node)->type->rcvmsg)((node), \
1144 (msg), (retaddr), (resp)); \
1145 } else { \
1146 TRAP_ERROR; \
1147 FREE((msg), M_NETGRAPH); \
1148 (error) = EINVAL; \
1149 } \
1150 } \
1151 } while (0)
1152
1153
1154 /*
1155 * Send a control message to a node
1156 */
1157 int
1158 ng_send_msg(node_p here, struct ng_mesg *msg, const char *address,
1159 struct ng_mesg **rptr)
1160 {
1161 node_p dest = NULL;
1162 char *retaddr = NULL;
1163 int error;
1164
1165 /* Find the target node */
1166 error = ng_path2node(here, address, &dest, &retaddr);
1167 if (error) {
1168 FREE(msg, M_NETGRAPH);
1169 return error;
1170 }
1171
1172 /* Make sure the resp field is null before we start */
1173 if (rptr != NULL)
1174 *rptr = NULL;
1175
1176 CALL_MSG_HANDLER(error, dest, msg, retaddr, rptr);
1177
1178 /* Make sure that if there is a response, it has the RESP bit set */
1179 if ((error == 0) && rptr && *rptr)
1180 (*rptr)->header.flags |= NGF_RESP;
1181
1182 /*
1183 * If we had a return address it is up to us to free it. They should
1184 * have taken a copy if they needed to make a delayed response.
1185 */
1186 if (retaddr)
1187 FREE(retaddr, M_NETGRAPH);
1188 return (error);
1189 }
1190
1191 /*
1192 * Implement the 'generic' control messages
1193 */
1194 static int
1195 ng_generic_msg(node_p here, struct ng_mesg *msg, const char *retaddr,
1196 struct ng_mesg **resp)
1197 {
1198 int error = 0;
1199
1200 if (msg->header.typecookie != NGM_GENERIC_COOKIE) {
1201 TRAP_ERROR;
1202 FREE(msg, M_NETGRAPH);
1203 return (EINVAL);
1204 }
1205 switch (msg->header.cmd) {
1206 case NGM_SHUTDOWN:
1207 ng_rmnode(here);
1208 break;
1209 case NGM_MKPEER:
1210 {
1211 struct ngm_mkpeer *const mkp = (struct ngm_mkpeer *) msg->data;
1212
1213 if (msg->header.arglen != sizeof(*mkp)) {
1214 TRAP_ERROR;
1215 return (EINVAL);
1216 }
1217 mkp->type[sizeof(mkp->type) - 1] = '\0';
1218 mkp->ourhook[sizeof(mkp->ourhook) - 1] = '\0';
1219 mkp->peerhook[sizeof(mkp->peerhook) - 1] = '\0';
1220 error = ng_mkpeer(here, mkp->ourhook, mkp->peerhook, mkp->type);
1221 break;
1222 }
1223 case NGM_CONNECT:
1224 {
1225 struct ngm_connect *const con =
1226 (struct ngm_connect *) msg->data;
1227 node_p node2;
1228
1229 if (msg->header.arglen != sizeof(*con)) {
1230 TRAP_ERROR;
1231 return (EINVAL);
1232 }
1233 con->path[sizeof(con->path) - 1] = '\0';
1234 con->ourhook[sizeof(con->ourhook) - 1] = '\0';
1235 con->peerhook[sizeof(con->peerhook) - 1] = '\0';
1236 error = ng_path2node(here, con->path, &node2, NULL);
1237 if (error)
1238 break;
1239 error = ng_con_nodes(here, con->ourhook, node2, con->peerhook);
1240 break;
1241 }
1242 case NGM_NAME:
1243 {
1244 struct ngm_name *const nam = (struct ngm_name *) msg->data;
1245
1246 if (msg->header.arglen != sizeof(*nam)) {
1247 TRAP_ERROR;
1248 return (EINVAL);
1249 }
1250 nam->name[sizeof(nam->name) - 1] = '\0';
1251 error = ng_name_node(here, nam->name);
1252 break;
1253 }
1254 case NGM_RMHOOK:
1255 {
1256 struct ngm_rmhook *const rmh = (struct ngm_rmhook *) msg->data;
1257 hook_p hook;
1258
1259 if (msg->header.arglen != sizeof(*rmh)) {
1260 TRAP_ERROR;
1261 return (EINVAL);
1262 }
1263 rmh->ourhook[sizeof(rmh->ourhook) - 1] = '\0';
1264 if ((hook = ng_findhook(here, rmh->ourhook)) != NULL)
1265 ng_destroy_hook(hook);
1266 break;
1267 }
1268 case NGM_NODEINFO:
1269 {
1270 struct nodeinfo *ni;
1271 struct ng_mesg *rp;
1272
1273 /* Get response struct */
1274 if (resp == NULL) {
1275 error = EINVAL;
1276 break;
1277 }
1278 NG_MKRESPONSE(rp, msg, sizeof(*ni), M_NOWAIT);
1279 if (rp == NULL) {
1280 error = ENOMEM;
1281 break;
1282 }
1283
1284 /* Fill in node info */
1285 ni = (struct nodeinfo *) rp->data;
1286 if (here->name != NULL)
1287 strncpy(ni->name, here->name, NG_NODELEN);
1288 strncpy(ni->type, here->type->name, NG_TYPELEN);
1289 ni->id = ng_node2ID(here);
1290 ni->hooks = here->numhooks;
1291 *resp = rp;
1292 break;
1293 }
1294 case NGM_LISTHOOKS:
1295 {
1296 const int nhooks = here->numhooks;
1297 struct hooklist *hl;
1298 struct nodeinfo *ni;
1299 struct ng_mesg *rp;
1300 hook_p hook;
1301
1302 /* Get response struct */
1303 if (resp == NULL) {
1304 error = EINVAL;
1305 break;
1306 }
1307 NG_MKRESPONSE(rp, msg, sizeof(*hl)
1308 + (nhooks * sizeof(struct linkinfo)), M_NOWAIT);
1309 if (rp == NULL) {
1310 error = ENOMEM;
1311 break;
1312 }
1313 hl = (struct hooklist *) rp->data;
1314 ni = &hl->nodeinfo;
1315
1316 /* Fill in node info */
1317 if (here->name)
1318 strncpy(ni->name, here->name, NG_NODELEN);
1319 strncpy(ni->type, here->type->name, NG_TYPELEN);
1320 ni->id = ng_node2ID(here);
1321
1322 /* Cycle through the linked list of hooks */
1323 ni->hooks = 0;
1324 LIST_FOREACH(hook, &here->hooks, hooks) {
1325 struct linkinfo *const link = &hl->link[ni->hooks];
1326
1327 if (ni->hooks >= nhooks) {
1328 log(LOG_ERR, "%s: number of %s changed\n",
1329 __FUNCTION__, "hooks");
1330 break;
1331 }
1332 if ((hook->flags & HK_INVALID) != 0)
1333 continue;
1334 strncpy(link->ourhook, hook->name, NG_HOOKLEN);
1335 strncpy(link->peerhook, hook->peer->name, NG_HOOKLEN);
1336 if (hook->peer->node->name != NULL)
1337 strncpy(link->nodeinfo.name,
1338 hook->peer->node->name, NG_NODELEN);
1339 strncpy(link->nodeinfo.type,
1340 hook->peer->node->type->name, NG_TYPELEN);
1341 link->nodeinfo.id = ng_node2ID(hook->peer->node);
1342 link->nodeinfo.hooks = hook->peer->node->numhooks;
1343 ni->hooks++;
1344 }
1345 *resp = rp;
1346 break;
1347 }
1348
1349 case NGM_LISTNAMES:
1350 case NGM_LISTNODES:
1351 {
1352 const int unnamed = (msg->header.cmd == NGM_LISTNODES);
1353 struct namelist *nl;
1354 struct ng_mesg *rp;
1355 node_p node;
1356 int num = 0;
1357
1358 if (resp == NULL) {
1359 error = EINVAL;
1360 break;
1361 }
1362
1363 /* Count number of nodes */
1364 LIST_FOREACH(node, &nodelist, nodes) {
1365 if (unnamed || node->name != NULL)
1366 num++;
1367 }
1368
1369 /* Get response struct */
1370 if (resp == NULL) {
1371 error = EINVAL;
1372 break;
1373 }
1374 NG_MKRESPONSE(rp, msg, sizeof(*nl)
1375 + (num * sizeof(struct nodeinfo)), M_NOWAIT);
1376 if (rp == NULL) {
1377 error = ENOMEM;
1378 break;
1379 }
1380 nl = (struct namelist *) rp->data;
1381
1382 /* Cycle through the linked list of nodes */
1383 nl->numnames = 0;
1384 LIST_FOREACH(node, &nodelist, nodes) {
1385 struct nodeinfo *const np = &nl->nodeinfo[nl->numnames];
1386
1387 if (nl->numnames >= num) {
1388 log(LOG_ERR, "%s: number of %s changed\n",
1389 __FUNCTION__, "nodes");
1390 break;
1391 }
1392 if ((node->flags & NG_INVALID) != 0)
1393 continue;
1394 if (!unnamed && node->name == NULL)
1395 continue;
1396 if (node->name != NULL)
1397 strncpy(np->name, node->name, NG_NODELEN);
1398 strncpy(np->type, node->type->name, NG_TYPELEN);
1399 np->id = ng_node2ID(node);
1400 np->hooks = node->numhooks;
1401 nl->numnames++;
1402 }
1403 *resp = rp;
1404 break;
1405 }
1406
1407 case NGM_LISTTYPES:
1408 {
1409 struct typelist *tl;
1410 struct ng_mesg *rp;
1411 struct ng_type *type;
1412 int num = 0;
1413
1414 if (resp == NULL) {
1415 error = EINVAL;
1416 break;
1417 }
1418
1419 /* Count number of types */
1420 LIST_FOREACH(type, &typelist, types)
1421 num++;
1422
1423 /* Get response struct */
1424 if (resp == NULL) {
1425 error = EINVAL;
1426 break;
1427 }
1428 NG_MKRESPONSE(rp, msg, sizeof(*tl)
1429 + (num * sizeof(struct typeinfo)), M_NOWAIT);
1430 if (rp == NULL) {
1431 error = ENOMEM;
1432 break;
1433 }
1434 tl = (struct typelist *) rp->data;
1435
1436 /* Cycle through the linked list of types */
1437 tl->numtypes = 0;
1438 LIST_FOREACH(type, &typelist, types) {
1439 struct typeinfo *const tp = &tl->typeinfo[tl->numtypes];
1440
1441 if (tl->numtypes >= num) {
1442 log(LOG_ERR, "%s: number of %s changed\n",
1443 __FUNCTION__, "types");
1444 break;
1445 }
1446 strncpy(tp->type_name, type->name, NG_TYPELEN);
1447 tp->numnodes = type->refs;
1448 tl->numtypes++;
1449 }
1450 *resp = rp;
1451 break;
1452 }
1453
1454 case NGM_BINARY2ASCII:
1455 {
1456 int bufSize = 2000; /* XXX hard coded constant */
1457 const struct ng_parse_type *argstype;
1458 const struct ng_cmdlist *c;
1459 struct ng_mesg *rp, *binary, *ascii;
1460
1461 /* Data area must contain a valid netgraph message */
1462 binary = (struct ng_mesg *)msg->data;
1463 if (msg->header.arglen < sizeof(struct ng_mesg)
1464 || msg->header.arglen - sizeof(struct ng_mesg)
1465 < binary->header.arglen) {
1466 error = EINVAL;
1467 break;
1468 }
1469
1470 /* Get a response message with lots of room */
1471 NG_MKRESPONSE(rp, msg, sizeof(*ascii) + bufSize, M_NOWAIT);
1472 if (rp == NULL) {
1473 error = ENOMEM;
1474 break;
1475 }
1476 ascii = (struct ng_mesg *)rp->data;
1477
1478 /* Copy binary message header to response message payload */
1479 bcopy(binary, ascii, sizeof(*binary));
1480
1481 /* Find command by matching typecookie and command number */
1482 for (c = here->type->cmdlist;
1483 c != NULL && c->name != NULL; c++) {
1484 if (binary->header.typecookie == c->cookie
1485 && binary->header.cmd == c->cmd)
1486 break;
1487 }
1488 if (c == NULL || c->name == NULL) {
1489 for (c = ng_generic_cmds; c->name != NULL; c++) {
1490 if (binary->header.typecookie == c->cookie
1491 && binary->header.cmd == c->cmd)
1492 break;
1493 }
1494 if (c->name == NULL) {
1495 FREE(rp, M_NETGRAPH);
1496 error = ENOSYS;
1497 break;
1498 }
1499 }
1500
1501 /* Convert command name to ASCII */
1502 snprintf(ascii->header.cmdstr, sizeof(ascii->header.cmdstr),
1503 "%s", c->name);
1504
1505 /* Convert command arguments to ASCII */
1506 argstype = (binary->header.flags & NGF_RESP) ?
1507 c->respType : c->mesgType;
1508 if (argstype == NULL)
1509 *ascii->data = '\0';
1510 else {
1511 if ((error = ng_unparse(argstype,
1512 (u_char *)binary->data,
1513 ascii->data, bufSize)) != 0) {
1514 FREE(rp, M_NETGRAPH);
1515 break;
1516 }
1517 }
1518
1519 /* Return the result as struct ng_mesg plus ASCII string */
1520 bufSize = strlen(ascii->data) + 1;
1521 ascii->header.arglen = bufSize;
1522 rp->header.arglen = sizeof(*ascii) + bufSize;
1523 *resp = rp;
1524 break;
1525 }
1526
1527 case NGM_ASCII2BINARY:
1528 {
1529 int bufSize = 2000; /* XXX hard coded constant */
1530 const struct ng_cmdlist *c;
1531 const struct ng_parse_type *argstype;
1532 struct ng_mesg *rp, *ascii, *binary;
1533 int off = 0;
1534
1535 /* Data area must contain at least a struct ng_mesg + '\0' */
1536 ascii = (struct ng_mesg *)msg->data;
1537 if (msg->header.arglen < sizeof(*ascii) + 1
1538 || ascii->header.arglen < 1
1539 || msg->header.arglen
1540 < sizeof(*ascii) + ascii->header.arglen) {
1541 error = EINVAL;
1542 break;
1543 }
1544 ascii->data[ascii->header.arglen - 1] = '\0';
1545
1546 /* Get a response message with lots of room */
1547 NG_MKRESPONSE(rp, msg, sizeof(*binary) + bufSize, M_NOWAIT);
1548 if (rp == NULL) {
1549 error = ENOMEM;
1550 break;
1551 }
1552 binary = (struct ng_mesg *)rp->data;
1553
1554 /* Copy ASCII message header to response message payload */
1555 bcopy(ascii, binary, sizeof(*ascii));
1556
1557 /* Find command by matching ASCII command string */
1558 for (c = here->type->cmdlist;
1559 c != NULL && c->name != NULL; c++) {
1560 if (strcmp(ascii->header.cmdstr, c->name) == 0)
1561 break;
1562 }
1563 if (c == NULL || c->name == NULL) {
1564 for (c = ng_generic_cmds; c->name != NULL; c++) {
1565 if (strcmp(ascii->header.cmdstr, c->name) == 0)
1566 break;
1567 }
1568 if (c->name == NULL) {
1569 FREE(rp, M_NETGRAPH);
1570 error = ENOSYS;
1571 break;
1572 }
1573 }
1574
1575 /* Convert command name to binary */
1576 binary->header.cmd = c->cmd;
1577 binary->header.typecookie = c->cookie;
1578
1579 /* Convert command arguments to binary */
1580 argstype = (binary->header.flags & NGF_RESP) ?
1581 c->respType : c->mesgType;
1582 if (argstype == NULL)
1583 bufSize = 0;
1584 else {
1585 if ((error = ng_parse(argstype, ascii->data,
1586 &off, (u_char *)binary->data, &bufSize)) != 0) {
1587 FREE(rp, M_NETGRAPH);
1588 break;
1589 }
1590 }
1591
1592 /* Return the result */
1593 binary->header.arglen = bufSize;
1594 rp->header.arglen = sizeof(*binary) + bufSize;
1595 *resp = rp;
1596 break;
1597 }
1598
1599 case NGM_TEXT_STATUS:
1600 /*
1601 * This one is tricky as it passes the command down to the
1602 * actual node, even though it is a generic type command.
1603 * This means we must assume that the msg is already freed
1604 * when control passes back to us.
1605 */
1606 if (resp == NULL) {
1607 error = EINVAL;
1608 break;
1609 }
1610 if (here->type->rcvmsg != NULL)
1611 return((*here->type->rcvmsg)(here, msg, retaddr, resp));
1612 /* Fall through if rcvmsg not supported */
1613 default:
1614 TRAP_ERROR;
1615 error = EINVAL;
1616 }
1617 FREE(msg, M_NETGRAPH);
1618 return (error);
1619 }
1620
1621 /*
1622 * Send a data packet to a node. If the recipient has no
1623 * 'receive data' method, then silently discard the packet.
1624 */
1625 int
1626 ng_send_data(hook_p hook, struct mbuf *m, meta_p meta)
1627 {
1628 int (*rcvdata)(hook_p, struct mbuf *, meta_p);
1629 int error;
1630
1631 CHECK_DATA_MBUF(m);
1632 if (hook && (hook->flags & HK_INVALID) == 0) {
1633 rcvdata = hook->peer->node->type->rcvdata;
1634 if (rcvdata != NULL)
1635 error = (*rcvdata)(hook->peer, m, meta);
1636 else {
1637 error = 0;
1638 NG_FREE_DATA(m, meta);
1639 }
1640 } else {
1641 TRAP_ERROR;
1642 error = ENOTCONN;
1643 NG_FREE_DATA(m, meta);
1644 }
1645 return (error);
1646 }
1647
1648 /*
1649 * Send a queued data packet to a node. If the recipient has no
1650 * 'receive queued data' method, then try the 'receive data' method above.
1651 */
1652 int
1653 ng_send_dataq(hook_p hook, struct mbuf *m, meta_p meta)
1654 {
1655 int (*rcvdataq)(hook_p, struct mbuf *, meta_p);
1656 int error;
1657
1658 CHECK_DATA_MBUF(m);
1659 if (hook && (hook->flags & HK_INVALID) == 0) {
1660 rcvdataq = hook->peer->node->type->rcvdataq;
1661 if (rcvdataq != NULL)
1662 error = (*rcvdataq)(hook->peer, m, meta);
1663 else {
1664 error = ng_send_data(hook, m, meta);
1665 }
1666 } else {
1667 TRAP_ERROR;
1668 error = ENOTCONN;
1669 NG_FREE_DATA(m, meta);
1670 }
1671 return (error);
1672 }
1673
1674 /*
1675 * Copy a 'meta'.
1676 *
1677 * Returns new meta, or NULL if original meta is NULL or ENOMEM.
1678 */
1679 meta_p
1680 ng_copy_meta(meta_p meta)
1681 {
1682 meta_p meta2;
1683
1684 if (meta == NULL)
1685 return (NULL);
1686 MALLOC(meta2, meta_p, meta->used_len, M_NETGRAPH, M_NOWAIT);
1687 if (meta2 == NULL)
1688 return (NULL);
1689 meta2->allocated_len = meta->used_len;
1690 bcopy(meta, meta2, meta->used_len);
1691 return (meta2);
1692 }
1693
1694 /************************************************************************
1695 Module routines
1696 ************************************************************************/
1697
1698 /*
1699 * Handle the loading/unloading of a netgraph node type module
1700 */
1701 int
1702 ng_mod_event(module_t mod, int event, void *data)
1703 {
1704 struct ng_type *const type = data;
1705 int s, error = 0;
1706
1707 switch (event) {
1708 case MOD_LOAD:
1709
1710 /* Register new netgraph node type */
1711 s = splnet();
1712 if ((error = ng_newtype(type)) != 0) {
1713 splx(s);
1714 break;
1715 }
1716
1717 /* Call type specific code */
1718 if (type->mod_event != NULL)
1719 if ((error = (*type->mod_event)(mod, event, data)) != 0)
1720 LIST_REMOVE(type, types);
1721 splx(s);
1722 break;
1723
1724 case MOD_UNLOAD:
1725 s = splnet();
1726 if (type->refs != 0) /* make sure no nodes exist! */
1727 error = EBUSY;
1728 else {
1729 if (type->mod_event != NULL) { /* check with type */
1730 error = (*type->mod_event)(mod, event, data);
1731 if (error != 0) { /* type refuses.. */
1732 splx(s);
1733 break;
1734 }
1735 }
1736 LIST_REMOVE(type, types);
1737 }
1738 splx(s);
1739 break;
1740
1741 default:
1742 if (type->mod_event != NULL)
1743 error = (*type->mod_event)(mod, event, data);
1744 else
1745 error = 0; /* XXX ? */
1746 break;
1747 }
1748 return (error);
1749 }
1750
1751 /*
1752 * Handle loading and unloading for this code.
1753 * The only thing we need to link into is the NETISR strucure.
1754 */
1755 static int
1756 ngb_mod_event(module_t mod, int event, void *data)
1757 {
1758 int s, error = 0;
1759
1760 switch (event) {
1761 case MOD_LOAD:
1762 /* Register line discipline */
1763 s = splimp();
1764 error = register_netisr(NETISR_NETGRAPH, ngintr);
1765 splx(s);
1766 break;
1767 case MOD_UNLOAD:
1768 /* You cant unload it because an interface may be using it. */
1769 error = EBUSY;
1770 break;
1771 default:
1772 error = EOPNOTSUPP;
1773 break;
1774 }
1775 return (error);
1776 }
1777
1778 static moduledata_t netgraph_mod = {
1779 "netgraph",
1780 ngb_mod_event,
1781 (NULL)
1782 };
1783 DECLARE_MODULE(netgraph, netgraph_mod, SI_SUB_DRIVERS, SI_ORDER_MIDDLE);
1784
1785 /************************************************************************
1786 Queueing routines
1787 ************************************************************************/
1788
1789 /* The structure for queueing across ISR switches */
1790 struct ng_queue_entry {
1791 u_long flags;
1792 struct ng_queue_entry *next;
1793 union {
1794 struct {
1795 hook_p da_hook; /* target hook */
1796 struct mbuf *da_m;
1797 meta_p da_meta;
1798 } data;
1799 struct {
1800 struct ng_mesg *msg_msg;
1801 node_p msg_node;
1802 void *msg_retaddr;
1803 } msg;
1804 } body;
1805 };
1806 #define NGQF_DATA 0x01 /* the queue element is data */
1807 #define NGQF_MESG 0x02 /* the queue element is a message */
1808
1809 static struct ng_queue_entry *ngqbase; /* items to be unqueued */
1810 static struct ng_queue_entry *ngqlast; /* last item queued */
1811 static const int ngqroom = 64; /* max items to queue */
1812 static int ngqsize; /* number of items in queue */
1813
1814 static struct ng_queue_entry *ngqfree; /* free ones */
1815 static const int ngqfreemax = 16;/* cache at most this many */
1816 static int ngqfreesize; /* number of cached entries */
1817
1818 /*
1819 * Get a queue entry
1820 */
1821 static struct ng_queue_entry *
1822 ng_getqblk(void)
1823 {
1824 register struct ng_queue_entry *q;
1825 int s;
1826
1827 /* Could be guarding against tty ints or whatever */
1828 s = splhigh();
1829
1830 /* Try get a cached queue block, or else allocate a new one */
1831 if ((q = ngqfree) == NULL) {
1832 splx(s);
1833 if (ngqsize < ngqroom) { /* don't worry about races */
1834 MALLOC(q, struct ng_queue_entry *,
1835 sizeof(*q), M_NETGRAPH, M_NOWAIT);
1836 }
1837 } else {
1838 ngqfree = q->next;
1839 ngqfreesize--;
1840 splx(s);
1841 }
1842 return (q);
1843 }
1844
1845 /*
1846 * Release a queue entry
1847 */
1848 #define RETURN_QBLK(q) \
1849 do { \
1850 int s; \
1851 if (ngqfreesize < ngqfreemax) { /* don't worry about races */ \
1852 s = splhigh(); \
1853 (q)->next = ngqfree; \
1854 ngqfree = (q); \
1855 ngqfreesize++; \
1856 splx(s); \
1857 } else { \
1858 FREE((q), M_NETGRAPH); \
1859 } \
1860 } while (0)
1861
1862 /*
1863 * Running at a raised (but we don't know which) processor priority level,
1864 * put the data onto a queue to be picked up by another PPL (probably splnet)
1865 */
1866 int
1867 ng_queue_data(hook_p hook, struct mbuf *m, meta_p meta)
1868 {
1869 struct ng_queue_entry *q;
1870 int s;
1871
1872 if (hook == NULL) {
1873 NG_FREE_DATA(m, meta);
1874 return (0);
1875 }
1876 if ((q = ng_getqblk()) == NULL) {
1877 NG_FREE_DATA(m, meta);
1878 return (ENOBUFS);
1879 }
1880
1881 /* Fill out the contents */
1882 q->flags = NGQF_DATA;
1883 q->next = NULL;
1884 q->body.data.da_hook = hook;
1885 q->body.data.da_m = m;
1886 q->body.data.da_meta = meta;
1887 s = splhigh(); /* protect refs and queue */
1888 hook->refs++; /* don't let it go away while on the queue */
1889
1890 /* Put it on the queue */
1891 if (ngqbase) {
1892 ngqlast->next = q;
1893 } else {
1894 ngqbase = q;
1895 }
1896 ngqlast = q;
1897 ngqsize++;
1898 splx(s);
1899
1900 /* Schedule software interrupt to handle it later */
1901 schednetisr(NETISR_NETGRAPH);
1902 return (0);
1903 }
1904
1905 /*
1906 * Running at a raised (but we don't know which) processor priority level,
1907 * put the msg onto a queue to be picked up by another PPL (probably splnet)
1908 */
1909 int
1910 ng_queue_msg(node_p here, struct ng_mesg *msg, const char *address)
1911 {
1912 register struct ng_queue_entry *q;
1913 int s;
1914 node_p dest = NULL;
1915 char *retaddr = NULL;
1916 int error;
1917
1918 /* Find the target node. */
1919 error = ng_path2node(here, address, &dest, &retaddr);
1920 if (error) {
1921 FREE(msg, M_NETGRAPH);
1922 return (error);
1923 }
1924 if ((q = ng_getqblk()) == NULL) {
1925 FREE(msg, M_NETGRAPH);
1926 if (retaddr)
1927 FREE(retaddr, M_NETGRAPH);
1928 return (ENOBUFS);
1929 }
1930
1931 /* Fill out the contents */
1932 q->flags = NGQF_MESG;
1933 q->next = NULL;
1934 q->body.msg.msg_node = dest;
1935 q->body.msg.msg_msg = msg;
1936 q->body.msg.msg_retaddr = retaddr;
1937 s = splhigh(); /* protect refs and queue */
1938 dest->refs++; /* don't let it go away while on the queue */
1939
1940 /* Put it on the queue */
1941 if (ngqbase) {
1942 ngqlast->next = q;
1943 } else {
1944 ngqbase = q;
1945 }
1946 ngqlast = q;
1947 ngqsize++;
1948 splx(s);
1949
1950 /* Schedule software interrupt to handle it later */
1951 schednetisr(NETISR_NETGRAPH);
1952 return (0);
1953 }
1954
1955 /*
1956 * Pick an item off the queue, process it, and dispose of the queue entry.
1957 * Should be running at splnet.
1958 */
1959 static void
1960 ngintr(void)
1961 {
1962 hook_p hook;
1963 struct ng_queue_entry *ngq;
1964 struct mbuf *m;
1965 meta_p meta;
1966 void *retaddr;
1967 struct ng_mesg *msg;
1968 node_p node;
1969 int error = 0;
1970 int s;
1971
1972 while (1) {
1973 s = splhigh();
1974 if ((ngq = ngqbase)) {
1975 ngqbase = ngq->next;
1976 ngqsize--;
1977 }
1978 splx(s);
1979 if (ngq == NULL)
1980 return;
1981 switch (ngq->flags) {
1982 case NGQF_DATA:
1983 hook = ngq->body.data.da_hook;
1984 m = ngq->body.data.da_m;
1985 meta = ngq->body.data.da_meta;
1986 RETURN_QBLK(ngq);
1987 NG_SEND_DATAQ(error, hook, m, meta);
1988 ng_unref_hook(hook);
1989 break;
1990 case NGQF_MESG:
1991 node = ngq->body.msg.msg_node;
1992 msg = ngq->body.msg.msg_msg;
1993 retaddr = ngq->body.msg.msg_retaddr;
1994 RETURN_QBLK(ngq);
1995 if (node->flags & NG_INVALID) {
1996 FREE(msg, M_NETGRAPH);
1997 } else {
1998 CALL_MSG_HANDLER(error, node, msg,
1999 retaddr, NULL);
2000 }
2001 ng_unref(node);
2002 if (retaddr)
2003 FREE(retaddr, M_NETGRAPH);
2004 break;
2005 default:
2006 RETURN_QBLK(ngq);
2007 }
2008 }
2009 }
2010
2011
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