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: src/sys/netgraph/ng_base.c,v 1.11.2.17 2002/07/02 23:44:02 archie Exp $
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 <sys/sysctl.h>
59 #include <sys/vnode.h>
60 #include <machine/limits.h>
61
62 #include <sys/thread2.h>
63 #include <sys/msgport2.h>
64 #include <sys/mplock2.h>
65
66 #include <net/netisr.h>
67
68 #include <netgraph/ng_message.h>
69 #include <netgraph/netgraph.h>
70 #include <netgraph/ng_parse.h>
71
72 MODULE_VERSION(netgraph, NG_ABI_VERSION);
73
74 union netmsg;
75
76 /* List of all nodes */
77 static LIST_HEAD(, ng_node) nodelist;
78
79 /* List of installed types */
80 static LIST_HEAD(, ng_type) typelist;
81
82 /* Hash releted definitions */
83 #define ID_HASH_SIZE 32 /* most systems wont need even this many */
84 static LIST_HEAD(, ng_node) ID_hash[ID_HASH_SIZE];
85 /* Don't nead to initialise them because it's a LIST */
86
87 /* Internal functions */
88 static int ng_add_hook(node_p node, const char *name, hook_p * hookp);
89 static int ng_connect(hook_p hook1, hook_p hook2);
90 static void ng_disconnect_hook(hook_p hook);
91 static int ng_generic_msg(node_p here, struct ng_mesg *msg,
92 const char *retaddr, struct ng_mesg ** resp);
93 static ng_ID_t ng_decodeidname(const char *name);
94 static int ngb_mod_event(module_t mod, int event, void *data);
95 static void ngintr(union netmsg *);
96 static int ng_load_module(const char *);
97
98 /* Our own netgraph malloc type */
99 MALLOC_DEFINE(M_NETGRAPH, "netgraph", "netgraph structures and ctrl messages");
100
101 /* Set this to Debugger("X") to catch all errors as they occur */
102 #ifndef TRAP_ERROR
103 #define TRAP_ERROR
104 #endif
105
106 static ng_ID_t nextID = 1;
107
108 #ifdef INVARIANTS
109 #define CHECK_DATA_MBUF(m) do { \
110 struct mbuf *n; \
111 int total; \
112 \
113 if (((m)->m_flags & M_PKTHDR) == 0) \
114 panic("%s: !PKTHDR", __func__); \
115 for (total = 0, n = (m); n != NULL; n = n->m_next) \
116 total += n->m_len; \
117 if ((m)->m_pkthdr.len != total) { \
118 panic("%s: %d != %d", \
119 __func__, (m)->m_pkthdr.len, total); \
120 } \
121 } while (0)
122 #else
123 #define CHECK_DATA_MBUF(m)
124 #endif
125
126
127 /************************************************************************
128 Parse type definitions for generic messages
129 ************************************************************************/
130
131 /* Handy structure parse type defining macro */
132 #define DEFINE_PARSE_STRUCT_TYPE(lo, up, args) \
133 static const struct ng_parse_struct_field \
134 ng_ ## lo ## _type_fields[] = NG_GENERIC_ ## up ## _INFO args; \
135 static const struct ng_parse_type ng_generic_ ## lo ## _type = { \
136 &ng_parse_struct_type, \
137 &ng_ ## lo ## _type_fields \
138 }
139
140 DEFINE_PARSE_STRUCT_TYPE(mkpeer, MKPEER, ());
141 DEFINE_PARSE_STRUCT_TYPE(connect, CONNECT, ());
142 DEFINE_PARSE_STRUCT_TYPE(name, NAME, ());
143 DEFINE_PARSE_STRUCT_TYPE(rmhook, RMHOOK, ());
144 DEFINE_PARSE_STRUCT_TYPE(nodeinfo, NODEINFO, ());
145 DEFINE_PARSE_STRUCT_TYPE(typeinfo, TYPEINFO, ());
146 DEFINE_PARSE_STRUCT_TYPE(linkinfo, LINKINFO, (&ng_generic_nodeinfo_type));
147
148 /* Get length of an array when the length is stored as a 32 bit
149 value immediately preceeding the array -- as with struct namelist
150 and struct typelist. */
151 static int
ng_generic_list_getLength(const struct ng_parse_type * type,const u_char * start,const u_char * buf)152 ng_generic_list_getLength(const struct ng_parse_type *type,
153 const u_char *start, const u_char *buf)
154 {
155 return *((const u_int32_t *)(buf - 4));
156 }
157
158 /* Get length of the array of struct linkinfo inside a struct hooklist */
159 static int
ng_generic_linkinfo_getLength(const struct ng_parse_type * type,const u_char * start,const u_char * buf)160 ng_generic_linkinfo_getLength(const struct ng_parse_type *type,
161 const u_char *start, const u_char *buf)
162 {
163 const struct hooklist *hl = (const struct hooklist *)start;
164
165 return hl->nodeinfo.hooks;
166 }
167
168 /* Array type for a variable length array of struct namelist */
169 static const struct ng_parse_array_info ng_nodeinfoarray_type_info = {
170 &ng_generic_nodeinfo_type,
171 &ng_generic_list_getLength
172 };
173 static const struct ng_parse_type ng_generic_nodeinfoarray_type = {
174 &ng_parse_array_type,
175 &ng_nodeinfoarray_type_info
176 };
177
178 #if 0 /* unused */
179 /* Array type for a variable length array of struct typelist */
180 static const struct ng_parse_array_info ng_typeinfoarray_type_info = {
181 &ng_generic_typeinfo_type,
182 &ng_generic_list_getLength
183 };
184 static const struct ng_parse_type ng_generic_typeinfoarray_type = {
185 &ng_parse_array_type,
186 &ng_typeinfoarray_type_info
187 };
188 #endif
189
190 /* Array type for array of struct linkinfo in struct hooklist */
191 static const struct ng_parse_array_info ng_generic_linkinfo_array_type_info = {
192 &ng_generic_linkinfo_type,
193 &ng_generic_linkinfo_getLength
194 };
195 static const struct ng_parse_type ng_generic_linkinfo_array_type = {
196 &ng_parse_array_type,
197 &ng_generic_linkinfo_array_type_info
198 };
199
200 #if 0 /* unused */
201 DEFINE_PARSE_STRUCT_TYPE(typelist, TYPELIST, (&ng_generic_nodeinfoarray_type));
202 #endif
203 DEFINE_PARSE_STRUCT_TYPE(hooklist, HOOKLIST,
204 (&ng_generic_nodeinfo_type, &ng_generic_linkinfo_array_type));
205 DEFINE_PARSE_STRUCT_TYPE(listnodes, LISTNODES,
206 (&ng_generic_nodeinfoarray_type));
207
208 /* List of commands and how to convert arguments to/from ASCII */
209 static const struct ng_cmdlist ng_generic_cmds[] = {
210 {
211 NGM_GENERIC_COOKIE,
212 NGM_SHUTDOWN,
213 "shutdown",
214 NULL,
215 NULL
216 },
217 {
218 NGM_GENERIC_COOKIE,
219 NGM_MKPEER,
220 "mkpeer",
221 &ng_generic_mkpeer_type,
222 NULL
223 },
224 {
225 NGM_GENERIC_COOKIE,
226 NGM_CONNECT,
227 "connect",
228 &ng_generic_connect_type,
229 NULL
230 },
231 {
232 NGM_GENERIC_COOKIE,
233 NGM_NAME,
234 "name",
235 &ng_generic_name_type,
236 NULL
237 },
238 {
239 NGM_GENERIC_COOKIE,
240 NGM_RMHOOK,
241 "rmhook",
242 &ng_generic_rmhook_type,
243 NULL
244 },
245 {
246 NGM_GENERIC_COOKIE,
247 NGM_NODEINFO,
248 "nodeinfo",
249 NULL,
250 &ng_generic_nodeinfo_type
251 },
252 {
253 NGM_GENERIC_COOKIE,
254 NGM_LISTHOOKS,
255 "listhooks",
256 NULL,
257 &ng_generic_hooklist_type
258 },
259 {
260 NGM_GENERIC_COOKIE,
261 NGM_LISTNAMES,
262 "listnames",
263 NULL,
264 &ng_generic_listnodes_type /* same as NGM_LISTNODES */
265 },
266 {
267 NGM_GENERIC_COOKIE,
268 NGM_LISTNODES,
269 "listnodes",
270 NULL,
271 &ng_generic_listnodes_type
272 },
273 {
274 NGM_GENERIC_COOKIE,
275 NGM_LISTTYPES,
276 "listtypes",
277 NULL,
278 &ng_generic_typeinfo_type
279 },
280 {
281 NGM_GENERIC_COOKIE,
282 NGM_TEXT_CONFIG,
283 "textconfig",
284 NULL,
285 &ng_parse_string_type
286 },
287 {
288 NGM_GENERIC_COOKIE,
289 NGM_TEXT_STATUS,
290 "textstatus",
291 NULL,
292 &ng_parse_string_type
293 },
294 {
295 NGM_GENERIC_COOKIE,
296 NGM_ASCII2BINARY,
297 "ascii2binary",
298 &ng_parse_ng_mesg_type,
299 &ng_parse_ng_mesg_type
300 },
301 {
302 NGM_GENERIC_COOKIE,
303 NGM_BINARY2ASCII,
304 "binary2ascii",
305 &ng_parse_ng_mesg_type,
306 &ng_parse_ng_mesg_type
307 },
308 { 0 }
309 };
310
311 /************************************************************************
312 Node routines
313 ************************************************************************/
314
315 static int
linker_api_available(void)316 linker_api_available(void)
317 {
318 /* linker_* API won't work without a process context */
319 if (curproc == NULL)
320 return 0;
321 /*
322 * nlookup_init() relies on namei_oc to be initialized,
323 * but it's not when the netgraph module is loaded during boot.
324 */
325 if (namei_oc == NULL)
326 return 0;
327 return 1;
328 }
329
330 static int
ng_load_module(const char * name)331 ng_load_module(const char *name)
332 {
333 char *path, filename[NG_TYPESIZ + 3];
334 linker_file_t lf;
335 int error;
336
337 if (!linker_api_available())
338 return (ENXIO);
339
340 /* Not found, try to load it as a loadable module */
341 ksnprintf(filename, sizeof(filename), "ng_%s.ko", name);
342 if ((path = linker_search_path(filename)) == NULL)
343 return (ENXIO);
344 error = linker_load_file(path, &lf);
345 kfree(path, M_LINKER);
346 if (error == 0)
347 lf->userrefs++; /* pretend kldload'ed */
348 return (error);
349 }
350
351 /*
352 * Instantiate a node of the requested type
353 */
354 int
ng_make_node(const char * typename,node_p * nodepp)355 ng_make_node(const char *typename, node_p *nodepp)
356 {
357 struct ng_type *type;
358
359 /* Check that the type makes sense */
360 if (typename == NULL) {
361 TRAP_ERROR;
362 return (EINVAL);
363 }
364
365 /* Locate the node type */
366 if ((type = ng_findtype(typename)) == NULL)
367 return (ENXIO);
368
369 /* Call the constructor */
370 if (type->constructor != NULL)
371 return ((*type->constructor)(nodepp));
372 else
373 return (ng_make_node_common(type, nodepp));
374 }
375
376 /*
377 * Generic node creation. Called by node constructors.
378 * The returned node has a reference count of 1.
379 */
380 int
ng_make_node_common(struct ng_type * type,node_p * nodepp)381 ng_make_node_common(struct ng_type *type, node_p *nodepp)
382 {
383 node_p node;
384
385 /* Require the node type to have been already installed */
386 if (ng_findtype(type->name) == NULL) {
387 TRAP_ERROR;
388 return (EINVAL);
389 }
390
391 /* Make a node and try attach it to the type */
392 node = kmalloc(sizeof(*node), M_NETGRAPH, M_NOWAIT | M_ZERO);
393 if (node == NULL) {
394 TRAP_ERROR;
395 return (ENOMEM);
396 }
397 node->type = type;
398 node->refs++; /* note reference */
399 type->refs++;
400
401 /* Link us into the node linked list */
402 LIST_INSERT_HEAD(&nodelist, node, nodes);
403
404 /* Initialize hook list for new node */
405 LIST_INIT(&node->hooks);
406
407 /* get an ID and put us in the hash chain */
408 node->ID = nextID++; /* 137 per second for 1 year before wrap */
409 LIST_INSERT_HEAD(&ID_hash[node->ID % ID_HASH_SIZE], node, idnodes);
410
411 /* Done */
412 *nodepp = node;
413 return (0);
414 }
415
416 /*
417 * Forceably start the shutdown process on a node. Either call
418 * it's shutdown method, or do the default shutdown if there is
419 * no type-specific method.
420 *
421 * Persistent nodes must have a type-specific method which
422 * resets the NG_INVALID flag.
423 */
424 void
ng_rmnode(node_p node)425 ng_rmnode(node_p node)
426 {
427 /* Check if it's already shutting down */
428 if ((node->flags & NG_INVALID) != 0)
429 return;
430
431 /* Add an extra reference so it doesn't go away during this */
432 node->refs++;
433
434 /* Mark it invalid so any newcomers know not to try use it */
435 node->flags |= NG_INVALID;
436
437 /* Ask the type if it has anything to do in this case */
438 if (node->type && node->type->shutdown)
439 (*node->type->shutdown)(node);
440 else { /* do the default thing */
441 ng_unname(node);
442 ng_cutlinks(node);
443 ng_unref(node);
444 }
445
446 /* Remove extra reference, possibly the last */
447 ng_unref(node);
448 }
449
450 /*
451 * Called by the destructor to remove any STANDARD external references
452 */
453 void
ng_cutlinks(node_p node)454 ng_cutlinks(node_p node)
455 {
456 hook_p hook;
457
458 /* Make sure that this is set to stop infinite loops */
459 node->flags |= NG_INVALID;
460
461 /* If we have sleepers, wake them up; they'll see NG_INVALID */
462 if (node->sleepers)
463 wakeup(node);
464
465 /* Notify all remaining connected nodes to disconnect */
466 while ((hook = LIST_FIRST(&node->hooks)) != NULL)
467 ng_destroy_hook(hook);
468 }
469
470 /*
471 * Remove a reference to the node, possibly the last
472 */
473 void
ng_unref(node_p node)474 ng_unref(node_p node)
475 {
476 crit_enter();
477 if (--node->refs <= 0) {
478 node->type->refs--;
479 LIST_REMOVE(node, nodes);
480 LIST_REMOVE(node, idnodes);
481 kfree(node, M_NETGRAPH);
482 }
483 crit_exit();
484 }
485
486 /*
487 * Wait for a node to come ready. Returns a node with a reference count;
488 * don't forget to drop it when we are done with it using ng_release_node().
489 */
490 int
ng_wait_node(node_p node,char * msg)491 ng_wait_node(node_p node, char *msg)
492 {
493 int error = 0;
494
495 if (msg == NULL)
496 msg = "netgraph";
497 crit_enter();
498 node->sleepers++;
499 node->refs++; /* the sleeping process counts as a reference */
500 while ((node->flags & (NG_BUSY | NG_INVALID)) == NG_BUSY)
501 error = tsleep(node, PCATCH, msg, 0);
502 node->sleepers--;
503 if (node->flags & NG_INVALID) {
504 TRAP_ERROR;
505 error = ENXIO;
506 } else {
507 KASSERT(node->refs > 1,
508 ("%s: refs=%d", __func__, node->refs));
509 node->flags |= NG_BUSY;
510 }
511 crit_exit();
512
513 /* Release the reference we had on it */
514 if (error != 0)
515 ng_unref(node);
516 return error;
517 }
518
519 /*
520 * Release a node acquired via ng_wait_node()
521 */
522 void
ng_release_node(node_p node)523 ng_release_node(node_p node)
524 {
525 /* Declare that we don't want it */
526 node->flags &= ~NG_BUSY;
527
528 /* If we have sleepers, then wake them up */
529 if (node->sleepers)
530 wakeup(node);
531
532 /* We also have a reference.. drop it too */
533 ng_unref(node);
534 }
535
536 /************************************************************************
537 Node ID handling
538 ************************************************************************/
539 static node_p
ng_ID2node(ng_ID_t ID)540 ng_ID2node(ng_ID_t ID)
541 {
542 node_p np;
543 LIST_FOREACH(np, &ID_hash[ID % ID_HASH_SIZE], idnodes) {
544 if ((np->flags & NG_INVALID) == 0 && np->ID == ID)
545 break;
546 }
547 return(np);
548 }
549
550 ng_ID_t
ng_node2ID(node_p node)551 ng_node2ID(node_p node)
552 {
553 return (node->ID);
554 }
555
556 /************************************************************************
557 Node name handling
558 ************************************************************************/
559
560 /*
561 * Assign a node a name. Once assigned, the name cannot be changed.
562 */
563 int
ng_name_node(node_p node,const char * name)564 ng_name_node(node_p node, const char *name)
565 {
566 int i;
567
568 /* Check the name is valid */
569 for (i = 0; i < NG_NODESIZ; i++) {
570 if (name[i] == '\0' || name[i] == '.' || name[i] == ':')
571 break;
572 }
573 if (i == 0 || name[i] != '\0') {
574 TRAP_ERROR;
575 return (EINVAL);
576 }
577 if (ng_decodeidname(name) != 0) { /* valid IDs not allowed here */
578 TRAP_ERROR;
579 return (EINVAL);
580 }
581
582 /* Check the node isn't already named */
583 if (node->name != NULL) {
584 TRAP_ERROR;
585 return (EISCONN);
586 }
587
588 /* Check the name isn't already being used */
589 if (ng_findname(node, name) != NULL) {
590 TRAP_ERROR;
591 return (EADDRINUSE);
592 }
593
594 /* Allocate space and copy it */
595 node->name = kmalloc(strlen(name) + 1, M_NETGRAPH, M_NOWAIT);
596 if (node->name == NULL) {
597 TRAP_ERROR;
598 return (ENOMEM);
599 }
600 strcpy(node->name, name);
601
602 /* The name counts as a reference */
603 node->refs++;
604 return (0);
605 }
606
607 /*
608 * Find a node by absolute name. The name should NOT end with ':'
609 * The name "." means "this node" and "[xxx]" means "the node
610 * with ID (ie, at address) xxx".
611 *
612 * Returns the node if found, else NULL.
613 */
614 node_p
ng_findname(node_p this,const char * name)615 ng_findname(node_p this, const char *name)
616 {
617 node_p node;
618 ng_ID_t temp;
619
620 /* "." means "this node" */
621 if (strcmp(name, ".") == 0)
622 return(this);
623
624 /* Check for name-by-ID */
625 if ((temp = ng_decodeidname(name)) != 0) {
626 return (ng_ID2node(temp));
627 }
628
629 /* Find node by name */
630 LIST_FOREACH(node, &nodelist, nodes) {
631 if ((node->name != NULL)
632 && (strcmp(node->name, name) == 0)
633 && ((node->flags & NG_INVALID) == 0))
634 break;
635 }
636 return (node);
637 }
638
639 /*
640 * Decode a ID name, eg. "[f03034de]". Returns 0 if the
641 * string is not valid, otherwise returns the value.
642 */
643 static ng_ID_t
ng_decodeidname(const char * name)644 ng_decodeidname(const char *name)
645 {
646 const int len = strlen(name);
647 char *eptr;
648 u_long val;
649
650 /* Check for proper length, brackets, no leading junk */
651 if (len < 3 || name[0] != '[' || name[len - 1] != ']'
652 || !isxdigit(name[1]))
653 return (0);
654
655 /* Decode number */
656 val = strtoul(name + 1, &eptr, 16);
657 if (eptr - name != len - 1 || val == ULONG_MAX || val == 0)
658 return ((ng_ID_t)0);
659 return (ng_ID_t)val;
660 }
661
662 /*
663 * Remove a name from a node. This should only be called
664 * when shutting down and removing the node.
665 */
666 void
ng_unname(node_p node)667 ng_unname(node_p node)
668 {
669 if (node->name) {
670 kfree(node->name, M_NETGRAPH);
671 node->name = NULL;
672 ng_unref(node);
673 }
674 }
675
676 /************************************************************************
677 Hook routines
678
679 Names are not optional. Hooks are always connected, except for a
680 brief moment within these routines.
681
682 ************************************************************************/
683
684 /*
685 * Remove a hook reference
686 */
687 void
ng_unref_hook(hook_p hook)688 ng_unref_hook(hook_p hook)
689 {
690 crit_enter();
691 if (--hook->refs == 0)
692 kfree(hook, M_NETGRAPH);
693 crit_exit();
694 }
695
696 /*
697 * Add an unconnected hook to a node. Only used internally.
698 */
699 static int
ng_add_hook(node_p node,const char * name,hook_p * hookp)700 ng_add_hook(node_p node, const char *name, hook_p *hookp)
701 {
702 hook_p hook;
703 int error = 0;
704
705 /* Check that the given name is good */
706 if (name == NULL) {
707 TRAP_ERROR;
708 return (EINVAL);
709 }
710 if (ng_findhook(node, name) != NULL) {
711 TRAP_ERROR;
712 return (EEXIST);
713 }
714
715 /* Allocate the hook and link it up */
716 hook = kmalloc(sizeof(*hook), M_NETGRAPH, M_NOWAIT | M_ZERO);
717 if (hook == NULL) {
718 TRAP_ERROR;
719 return (ENOMEM);
720 }
721 hook->refs = 1;
722 hook->flags = HK_INVALID;
723 hook->node = node;
724 node->refs++; /* each hook counts as a reference */
725
726 /* Check if the node type code has something to say about it */
727 if (node->type->newhook != NULL)
728 if ((error = (*node->type->newhook)(node, hook, name)) != 0)
729 goto fail;
730
731 /*
732 * The 'type' agrees so far, so go ahead and link it in.
733 * We'll ask again later when we actually connect the hooks.
734 */
735 LIST_INSERT_HEAD(&node->hooks, hook, hooks);
736 node->numhooks++;
737
738 /* Set hook name */
739 hook->name = kmalloc(strlen(name) + 1, M_NETGRAPH, M_NOWAIT);
740 if (hook->name == NULL) {
741 error = ENOMEM;
742 LIST_REMOVE(hook, hooks);
743 node->numhooks--;
744 fail:
745 hook->node = NULL;
746 ng_unref(node);
747 ng_unref_hook(hook); /* this frees the hook */
748 return (error);
749 }
750 strcpy(hook->name, name);
751 if (hookp)
752 *hookp = hook;
753 return (error);
754 }
755
756 /*
757 * Connect a pair of hooks. Only used internally.
758 */
759 static int
ng_connect(hook_p hook1,hook_p hook2)760 ng_connect(hook_p hook1, hook_p hook2)
761 {
762 int error;
763
764 hook1->peer = hook2;
765 hook2->peer = hook1;
766
767 /* Give each node the opportunity to veto the impending connection */
768 if (hook1->node->type->connect) {
769 if ((error = (*hook1->node->type->connect) (hook1))) {
770 ng_destroy_hook(hook1); /* also zaps hook2 */
771 return (error);
772 }
773 }
774 if (hook2->node->type->connect) {
775 if ((error = (*hook2->node->type->connect) (hook2))) {
776 ng_destroy_hook(hook2); /* also zaps hook1 */
777 return (error);
778 }
779 }
780 hook1->flags &= ~HK_INVALID;
781 hook2->flags &= ~HK_INVALID;
782 return (0);
783 }
784
785 /*
786 * Find a hook
787 *
788 * Node types may supply their own optimized routines for finding
789 * hooks. If none is supplied, we just do a linear search.
790 */
791 hook_p
ng_findhook(node_p node,const char * name)792 ng_findhook(node_p node, const char *name)
793 {
794 hook_p hook;
795
796 if (node->type->findhook != NULL)
797 return (*node->type->findhook)(node, name);
798 LIST_FOREACH(hook, &node->hooks, hooks) {
799 if (hook->name != NULL
800 && strcmp(hook->name, name) == 0
801 && (hook->flags & HK_INVALID) == 0)
802 return (hook);
803 }
804 return (NULL);
805 }
806
807 /*
808 * Destroy a hook
809 *
810 * As hooks are always attached, this really destroys two hooks.
811 * The one given, and the one attached to it. Disconnect the hooks
812 * from each other first.
813 */
814 void
ng_destroy_hook(hook_p hook)815 ng_destroy_hook(hook_p hook)
816 {
817 hook_p peer = hook->peer;
818
819 hook->flags |= HK_INVALID; /* as soon as possible */
820 if (peer) {
821 peer->flags |= HK_INVALID; /* as soon as possible */
822 hook->peer = NULL;
823 peer->peer = NULL;
824 ng_disconnect_hook(peer);
825 }
826 ng_disconnect_hook(hook);
827 }
828
829 /*
830 * Notify the node of the hook's demise. This may result in more actions
831 * (e.g. shutdown) but we don't do that ourselves and don't know what
832 * happens there. If there is no appropriate handler, then just remove it
833 * (and decrement the reference count of it's node which in turn might
834 * make something happen).
835 */
836 static void
ng_disconnect_hook(hook_p hook)837 ng_disconnect_hook(hook_p hook)
838 {
839 node_p node = hook->node;
840
841 /*
842 * Remove the hook from the node's list to avoid possible recursion
843 * in case the disconnection results in node shutdown.
844 */
845 LIST_REMOVE(hook, hooks);
846 node->numhooks--;
847 if (node->type->disconnect) {
848 /*
849 * The type handler may elect to destroy the peer so don't
850 * trust its existance after this point.
851 */
852 (*node->type->disconnect) (hook);
853 }
854 ng_unref(node); /* might be the last reference */
855 if (hook->name)
856 kfree(hook->name, M_NETGRAPH);
857 hook->node = NULL; /* may still be referenced elsewhere */
858 ng_unref_hook(hook);
859 }
860
861 /*
862 * Take two hooks on a node and merge the connection so that the given node
863 * is effectively bypassed.
864 */
865 int
ng_bypass(hook_p hook1,hook_p hook2)866 ng_bypass(hook_p hook1, hook_p hook2)
867 {
868 if (hook1->node != hook2->node)
869 return (EINVAL);
870 hook1->peer->peer = hook2->peer;
871 hook2->peer->peer = hook1->peer;
872
873 /* XXX If we ever cache methods on hooks update them as well */
874 hook1->peer = NULL;
875 hook2->peer = NULL;
876 ng_destroy_hook(hook1);
877 ng_destroy_hook(hook2);
878 return (0);
879 }
880
881 /*
882 * Install a new netgraph type
883 */
884 int
ng_newtype(struct ng_type * tp)885 ng_newtype(struct ng_type *tp)
886 {
887 const size_t namelen = strlen(tp->name);
888
889 /* Check version and type name fields */
890 if (tp->version != NG_VERSION || namelen == 0 || namelen >= NG_TYPESIZ) {
891 TRAP_ERROR;
892 return (EINVAL);
893 }
894
895 /* Check for name collision */
896 if (ng_findtype(tp->name) != NULL) {
897 TRAP_ERROR;
898 return (EEXIST);
899 }
900
901 /* Link in new type */
902 LIST_INSERT_HEAD(&typelist, tp, types);
903 tp->refs = 1; /* first ref is linked list */
904 return (0);
905 }
906
907 /*
908 * Look for a type of the name given
909 */
910 struct ng_type *
ng_findtype(const char * typename)911 ng_findtype(const char *typename)
912 {
913 struct ng_type *type;
914
915 LIST_FOREACH(type, &typelist, types) {
916 if (strcmp(type->name, typename) == 0)
917 break;
918 }
919 return (type);
920 }
921
922
923 /************************************************************************
924 Composite routines
925 ************************************************************************/
926
927 /*
928 * Make a peer and connect. The order is arranged to minimise
929 * the work needed to back out in case of error.
930 */
931 int
ng_mkpeer(node_p node,const char * name,const char * name2,char * type)932 ng_mkpeer(node_p node, const char *name, const char *name2, char *type)
933 {
934 node_p node2;
935 hook_p hook;
936 hook_p hook2;
937 int error;
938
939 if ((error = ng_add_hook(node, name, &hook)))
940 return (error);
941
942 /* make sure we have the module needed */
943 if (ng_findtype(type) == NULL) {
944 /* Not found, try to load it as a loadable module */
945 error = ng_load_module(type);
946 if (error != 0) {
947 kprintf("required netgraph module ng_%s not loaded\n",
948 type);
949 return (error);
950 }
951 }
952 if ((error = ng_make_node(type, &node2))) {
953 ng_destroy_hook(hook);
954 return (error);
955 }
956 if ((error = ng_add_hook(node2, name2, &hook2))) {
957 ng_rmnode(node2);
958 ng_destroy_hook(hook);
959 return (error);
960 }
961
962 /*
963 * Actually link the two hooks together.. on failure they are
964 * destroyed so we don't have to do that here.
965 */
966 if ((error = ng_connect(hook, hook2)))
967 ng_rmnode(node2);
968 return (error);
969 }
970
971 /*
972 * Connect two nodes using the specified hooks
973 */
974 int
ng_con_nodes(node_p node,const char * name,node_p node2,const char * name2)975 ng_con_nodes(node_p node, const char *name, node_p node2, const char *name2)
976 {
977 int error;
978 hook_p hook;
979 hook_p hook2;
980
981 if ((error = ng_add_hook(node, name, &hook)))
982 return (error);
983 if ((error = ng_add_hook(node2, name2, &hook2))) {
984 ng_destroy_hook(hook);
985 return (error);
986 }
987 return (ng_connect(hook, hook2));
988 }
989
990 /*
991 * Parse and verify a string of the form: <NODE:><PATH>
992 *
993 * Such a string can refer to a specific node or a specific hook
994 * on a specific node, depending on how you look at it. In the
995 * latter case, the PATH component must not end in a dot.
996 *
997 * Both <NODE:> and <PATH> are optional. The <PATH> is a string
998 * of hook names separated by dots. This breaks out the original
999 * string, setting *nodep to "NODE" (or NULL if none) and *pathp
1000 * to "PATH" (or NULL if degenerate). Also, *hookp will point to
1001 * the final hook component of <PATH>, if any, otherwise NULL.
1002 *
1003 * This returns -1 if the path is malformed. The char ** are optional.
1004 */
1005
1006 int
ng_path_parse(char * addr,char ** nodep,char ** pathp,char ** hookp)1007 ng_path_parse(char *addr, char **nodep, char **pathp, char **hookp)
1008 {
1009 char *node, *path, *hook;
1010 int k;
1011
1012 /*
1013 * Extract absolute NODE, if any
1014 */
1015 for (path = addr; *path && *path != ':'; path++);
1016 if (*path) {
1017 node = addr; /* Here's the NODE */
1018 *path++ = '\0'; /* Here's the PATH */
1019
1020 /* Node name must not be empty */
1021 if (!*node)
1022 return -1;
1023
1024 /* A name of "." is OK; otherwise '.' not allowed */
1025 if (strcmp(node, ".") != 0) {
1026 for (k = 0; node[k]; k++)
1027 if (node[k] == '.')
1028 return -1;
1029 }
1030 } else {
1031 node = NULL; /* No absolute NODE */
1032 path = addr; /* Here's the PATH */
1033 }
1034
1035 /* Snoop for illegal characters in PATH */
1036 for (k = 0; path[k]; k++)
1037 if (path[k] == ':')
1038 return -1;
1039
1040 /* Check for no repeated dots in PATH */
1041 for (k = 0; path[k]; k++)
1042 if (path[k] == '.' && path[k + 1] == '.')
1043 return -1;
1044
1045 /* Remove extra (degenerate) dots from beginning or end of PATH */
1046 if (path[0] == '.')
1047 path++;
1048 if (*path && path[strlen(path) - 1] == '.')
1049 path[strlen(path) - 1] = 0;
1050
1051 /* If PATH has a dot, then we're not talking about a hook */
1052 if (*path) {
1053 for (hook = path, k = 0; path[k]; k++)
1054 if (path[k] == '.') {
1055 hook = NULL;
1056 break;
1057 }
1058 } else
1059 path = hook = NULL;
1060
1061 /* Done */
1062 if (nodep)
1063 *nodep = node;
1064 if (pathp)
1065 *pathp = path;
1066 if (hookp)
1067 *hookp = hook;
1068 return (0);
1069 }
1070
1071 /*
1072 * Given a path, which may be absolute or relative, and a starting node,
1073 * return the destination node. Compute the "return address" if desired.
1074 */
1075 int
ng_path2node(node_p here,const char * address,node_p * destp,char ** rtnp)1076 ng_path2node(node_p here, const char *address, node_p *destp, char **rtnp)
1077 {
1078 const node_p start = here;
1079 char fullpath[NG_PATHSIZ];
1080 char *nodename, *path, pbuf[2];
1081 node_p node;
1082 char *cp;
1083
1084 /* Initialize */
1085 if (rtnp)
1086 *rtnp = NULL;
1087 if (destp == NULL)
1088 return EINVAL;
1089 *destp = NULL;
1090
1091 /* Make a writable copy of address for ng_path_parse() */
1092 strncpy(fullpath, address, sizeof(fullpath) - 1);
1093 fullpath[sizeof(fullpath) - 1] = '\0';
1094
1095 /* Parse out node and sequence of hooks */
1096 if (ng_path_parse(fullpath, &nodename, &path, NULL) < 0) {
1097 TRAP_ERROR;
1098 return EINVAL;
1099 }
1100 if (path == NULL) {
1101 pbuf[0] = '.'; /* Needs to be writable */
1102 pbuf[1] = '\0';
1103 path = pbuf;
1104 }
1105
1106 /* For an absolute address, jump to the starting node */
1107 if (nodename) {
1108 node = ng_findname(here, nodename);
1109 if (node == NULL) {
1110 TRAP_ERROR;
1111 return (ENOENT);
1112 }
1113 } else
1114 node = here;
1115
1116 /* Now follow the sequence of hooks */
1117 for (cp = path; node != NULL && *cp != '\0'; ) {
1118 hook_p hook;
1119 char *segment;
1120
1121 /*
1122 * Break out the next path segment. Replace the dot we just
1123 * found with a NUL; "cp" points to the next segment (or the
1124 * NUL at the end).
1125 */
1126 for (segment = cp; *cp != '\0'; cp++) {
1127 if (*cp == '.') {
1128 *cp++ = '\0';
1129 break;
1130 }
1131 }
1132
1133 /* Empty segment */
1134 if (*segment == '\0')
1135 continue;
1136
1137 /* We have a segment, so look for a hook by that name */
1138 hook = ng_findhook(node, segment);
1139
1140 /* Can't get there from here... */
1141 if (hook == NULL
1142 || hook->peer == NULL
1143 || (hook->flags & HK_INVALID) != 0) {
1144 TRAP_ERROR;
1145 return (ENOENT);
1146 }
1147
1148 /* Hop on over to the next node */
1149 node = hook->peer->node;
1150 }
1151
1152 /* If node somehow missing, fail here (probably this is not needed) */
1153 if (node == NULL) {
1154 TRAP_ERROR;
1155 return (ENXIO);
1156 }
1157
1158 /* Now compute return address, i.e., the path to the sender */
1159 if (rtnp != NULL) {
1160 *rtnp = kmalloc(NG_NODESIZ + 1, M_NETGRAPH, M_NOWAIT);
1161 if (*rtnp == NULL) {
1162 TRAP_ERROR;
1163 return (ENOMEM);
1164 }
1165 if (start->name != NULL)
1166 ksprintf(*rtnp, "%s:", start->name);
1167 else
1168 ksprintf(*rtnp, "[%x]:", ng_node2ID(start));
1169 }
1170
1171 /* Done */
1172 *destp = node;
1173 return (0);
1174 }
1175
1176 /*
1177 * Call the appropriate message handler for the object.
1178 * It is up to the message handler to free the message.
1179 * If it's a generic message, handle it generically, otherwise
1180 * call the type's message handler (if it exists)
1181 * XXX (race). Remember that a queued message may reference a node
1182 * or hook that has just been invalidated. It will exist
1183 * as the queue code is holding a reference, but..
1184 */
1185
1186 #define CALL_MSG_HANDLER(error, node, msg, retaddr, resp) \
1187 do { \
1188 if((msg)->header.typecookie == NGM_GENERIC_COOKIE) { \
1189 (error) = ng_generic_msg((node), (msg), \
1190 (retaddr), (resp)); \
1191 } else { \
1192 if ((node)->type->rcvmsg != NULL) { \
1193 (error) = (*(node)->type->rcvmsg)((node), \
1194 (msg), (retaddr), (resp)); \
1195 } else { \
1196 TRAP_ERROR; \
1197 kfree((msg), M_NETGRAPH); \
1198 (error) = EINVAL; \
1199 } \
1200 } \
1201 } while (0)
1202
1203
1204 /*
1205 * Send a control message to a node
1206 */
1207 int
ng_send_msg(node_p here,struct ng_mesg * msg,const char * address,struct ng_mesg ** rptr)1208 ng_send_msg(node_p here, struct ng_mesg *msg, const char *address,
1209 struct ng_mesg **rptr)
1210 {
1211 node_p dest = NULL;
1212 char *retaddr = NULL;
1213 int error;
1214
1215 /* Find the target node */
1216 error = ng_path2node(here, address, &dest, &retaddr);
1217 if (error) {
1218 kfree(msg, M_NETGRAPH);
1219 return error;
1220 }
1221
1222 /* Make sure the resp field is null before we start */
1223 if (rptr != NULL)
1224 *rptr = NULL;
1225
1226 CALL_MSG_HANDLER(error, dest, msg, retaddr, rptr);
1227
1228 /* Make sure that if there is a response, it has the RESP bit set */
1229 if ((error == 0) && rptr && *rptr)
1230 (*rptr)->header.flags |= NGF_RESP;
1231
1232 /*
1233 * If we had a return address it is up to us to free it. They should
1234 * have taken a copy if they needed to make a delayed response.
1235 */
1236 if (retaddr)
1237 kfree(retaddr, M_NETGRAPH);
1238 return (error);
1239 }
1240
1241 /*
1242 * Implement the 'generic' control messages
1243 */
1244 static int
ng_generic_msg(node_p here,struct ng_mesg * msg,const char * retaddr,struct ng_mesg ** resp)1245 ng_generic_msg(node_p here, struct ng_mesg *msg, const char *retaddr,
1246 struct ng_mesg **resp)
1247 {
1248 int error = 0;
1249
1250 if (msg->header.typecookie != NGM_GENERIC_COOKIE) {
1251 TRAP_ERROR;
1252 kfree(msg, M_NETGRAPH);
1253 return (EINVAL);
1254 }
1255 switch (msg->header.cmd) {
1256 case NGM_SHUTDOWN:
1257 ng_rmnode(here);
1258 break;
1259 case NGM_MKPEER:
1260 {
1261 struct ngm_mkpeer *const mkp = (struct ngm_mkpeer *) msg->data;
1262
1263 if (msg->header.arglen != sizeof(*mkp)) {
1264 TRAP_ERROR;
1265 return (EINVAL);
1266 }
1267 mkp->type[sizeof(mkp->type) - 1] = '\0';
1268 mkp->ourhook[sizeof(mkp->ourhook) - 1] = '\0';
1269 mkp->peerhook[sizeof(mkp->peerhook) - 1] = '\0';
1270 error = ng_mkpeer(here, mkp->ourhook, mkp->peerhook, mkp->type);
1271 break;
1272 }
1273 case NGM_CONNECT:
1274 {
1275 struct ngm_connect *const con =
1276 (struct ngm_connect *) msg->data;
1277 node_p node2;
1278
1279 if (msg->header.arglen != sizeof(*con)) {
1280 TRAP_ERROR;
1281 return (EINVAL);
1282 }
1283 con->path[sizeof(con->path) - 1] = '\0';
1284 con->ourhook[sizeof(con->ourhook) - 1] = '\0';
1285 con->peerhook[sizeof(con->peerhook) - 1] = '\0';
1286 error = ng_path2node(here, con->path, &node2, NULL);
1287 if (error)
1288 break;
1289 error = ng_con_nodes(here, con->ourhook, node2, con->peerhook);
1290 break;
1291 }
1292 case NGM_NAME:
1293 {
1294 struct ngm_name *const nam = (struct ngm_name *) msg->data;
1295
1296 if (msg->header.arglen != sizeof(*nam)) {
1297 TRAP_ERROR;
1298 return (EINVAL);
1299 }
1300 nam->name[sizeof(nam->name) - 1] = '\0';
1301 error = ng_name_node(here, nam->name);
1302 break;
1303 }
1304 case NGM_RMHOOK:
1305 {
1306 struct ngm_rmhook *const rmh = (struct ngm_rmhook *) msg->data;
1307 hook_p hook;
1308
1309 if (msg->header.arglen != sizeof(*rmh)) {
1310 TRAP_ERROR;
1311 return (EINVAL);
1312 }
1313 rmh->ourhook[sizeof(rmh->ourhook) - 1] = '\0';
1314 if ((hook = ng_findhook(here, rmh->ourhook)) != NULL)
1315 ng_destroy_hook(hook);
1316 break;
1317 }
1318 case NGM_NODEINFO:
1319 {
1320 struct nodeinfo *ni;
1321 struct ng_mesg *rp;
1322
1323 /* Get response struct */
1324 if (resp == NULL) {
1325 error = EINVAL;
1326 break;
1327 }
1328 NG_MKRESPONSE(rp, msg, sizeof(*ni), M_NOWAIT);
1329 if (rp == NULL) {
1330 error = ENOMEM;
1331 break;
1332 }
1333
1334 /* Fill in node info */
1335 ni = (struct nodeinfo *) rp->data;
1336 if (here->name != NULL)
1337 strlcpy(ni->name, here->name, NG_NODESIZ);
1338 strlcpy(ni->type, here->type->name, NG_TYPESIZ);
1339 ni->id = ng_node2ID(here);
1340 ni->hooks = here->numhooks;
1341 *resp = rp;
1342 break;
1343 }
1344 case NGM_LISTHOOKS:
1345 {
1346 const int nhooks = here->numhooks;
1347 struct hooklist *hl;
1348 struct nodeinfo *ni;
1349 struct ng_mesg *rp;
1350 hook_p hook;
1351
1352 /* Get response struct */
1353 if (resp == NULL) {
1354 error = EINVAL;
1355 break;
1356 }
1357 NG_MKRESPONSE(rp, msg, sizeof(*hl)
1358 + (nhooks * sizeof(struct linkinfo)), M_NOWAIT);
1359 if (rp == NULL) {
1360 error = ENOMEM;
1361 break;
1362 }
1363 hl = (struct hooklist *) rp->data;
1364 ni = &hl->nodeinfo;
1365
1366 /* Fill in node info */
1367 if (here->name)
1368 strlcpy(ni->name, here->name, NG_NODESIZ);
1369 strlcpy(ni->type, here->type->name, NG_TYPESIZ);
1370 ni->id = ng_node2ID(here);
1371
1372 /* Cycle through the linked list of hooks */
1373 ni->hooks = 0;
1374 LIST_FOREACH(hook, &here->hooks, hooks) {
1375 struct linkinfo *const link = &hl->link[ni->hooks];
1376
1377 if (ni->hooks >= nhooks) {
1378 log(LOG_ERR, "%s: number of %s changed\n",
1379 __func__, "hooks");
1380 break;
1381 }
1382 if ((hook->flags & HK_INVALID) != 0)
1383 continue;
1384 strlcpy(link->ourhook, hook->name, NG_HOOKSIZ);
1385 strlcpy(link->peerhook, hook->peer->name, NG_HOOKSIZ);
1386 if (hook->peer->node->name != NULL)
1387 strlcpy(link->nodeinfo.name,
1388 hook->peer->node->name, NG_NODESIZ);
1389 strlcpy(link->nodeinfo.type,
1390 hook->peer->node->type->name, NG_TYPESIZ);
1391 link->nodeinfo.id = ng_node2ID(hook->peer->node);
1392 link->nodeinfo.hooks = hook->peer->node->numhooks;
1393 ni->hooks++;
1394 }
1395 *resp = rp;
1396 break;
1397 }
1398
1399 case NGM_LISTNAMES:
1400 case NGM_LISTNODES:
1401 {
1402 const int unnamed = (msg->header.cmd == NGM_LISTNODES);
1403 struct namelist *nl;
1404 struct ng_mesg *rp;
1405 node_p node;
1406 int num = 0;
1407
1408 if (resp == NULL) {
1409 error = EINVAL;
1410 break;
1411 }
1412
1413 /* Count number of nodes */
1414 LIST_FOREACH(node, &nodelist, nodes) {
1415 if ((node->flags & NG_INVALID) == 0
1416 && (unnamed || node->name != NULL))
1417 num++;
1418 }
1419
1420 /* Get response struct */
1421 if (resp == NULL) {
1422 error = EINVAL;
1423 break;
1424 }
1425 NG_MKRESPONSE(rp, msg, sizeof(*nl)
1426 + (num * sizeof(struct nodeinfo)), M_NOWAIT);
1427 if (rp == NULL) {
1428 error = ENOMEM;
1429 break;
1430 }
1431 nl = (struct namelist *) rp->data;
1432
1433 /* Cycle through the linked list of nodes */
1434 nl->numnames = 0;
1435 LIST_FOREACH(node, &nodelist, nodes) {
1436 struct nodeinfo *const np = &nl->nodeinfo[nl->numnames];
1437
1438 if (nl->numnames >= num) {
1439 log(LOG_ERR, "%s: number of %s changed\n",
1440 __func__, "nodes");
1441 break;
1442 }
1443 if ((node->flags & NG_INVALID) != 0)
1444 continue;
1445 if (!unnamed && node->name == NULL)
1446 continue;
1447 if (node->name != NULL)
1448 strlcpy(np->name, node->name, NG_NODESIZ);
1449 strlcpy(np->type, node->type->name, NG_TYPESIZ);
1450 np->id = ng_node2ID(node);
1451 np->hooks = node->numhooks;
1452 nl->numnames++;
1453 }
1454 *resp = rp;
1455 break;
1456 }
1457
1458 case NGM_LISTTYPES:
1459 {
1460 struct typelist *tl;
1461 struct ng_mesg *rp;
1462 struct ng_type *type;
1463 int num = 0;
1464
1465 if (resp == NULL) {
1466 error = EINVAL;
1467 break;
1468 }
1469
1470 /* Count number of types */
1471 LIST_FOREACH(type, &typelist, types)
1472 num++;
1473
1474 /* Get response struct */
1475 if (resp == NULL) {
1476 error = EINVAL;
1477 break;
1478 }
1479 NG_MKRESPONSE(rp, msg, sizeof(*tl)
1480 + (num * sizeof(struct typeinfo)), M_NOWAIT);
1481 if (rp == NULL) {
1482 error = ENOMEM;
1483 break;
1484 }
1485 tl = (struct typelist *) rp->data;
1486
1487 /* Cycle through the linked list of types */
1488 tl->numtypes = 0;
1489 LIST_FOREACH(type, &typelist, types) {
1490 struct typeinfo *const tp = &tl->typeinfo[tl->numtypes];
1491
1492 if (tl->numtypes >= num) {
1493 log(LOG_ERR, "%s: number of %s changed\n",
1494 __func__, "types");
1495 break;
1496 }
1497 strlcpy(tp->type_name, type->name, NG_TYPESIZ);
1498 tp->numnodes = type->refs - 1; /* don't count list */
1499 tl->numtypes++;
1500 }
1501 *resp = rp;
1502 break;
1503 }
1504
1505 case NGM_BINARY2ASCII:
1506 {
1507 int bufSize = 20 * 1024; /* XXX hard coded constant */
1508 const struct ng_parse_type *argstype;
1509 const struct ng_cmdlist *c;
1510 struct ng_mesg *rp, *binary, *ascii;
1511
1512 /* Data area must contain a valid netgraph message */
1513 binary = (struct ng_mesg *)msg->data;
1514 if (msg->header.arglen < sizeof(struct ng_mesg)
1515 || msg->header.arglen - sizeof(struct ng_mesg)
1516 < binary->header.arglen) {
1517 error = EINVAL;
1518 break;
1519 }
1520
1521 /* Get a response message with lots of room */
1522 NG_MKRESPONSE(rp, msg, sizeof(*ascii) + bufSize, M_NOWAIT);
1523 if (rp == NULL) {
1524 error = ENOMEM;
1525 break;
1526 }
1527 ascii = (struct ng_mesg *)rp->data;
1528
1529 /* Copy binary message header to response message payload */
1530 bcopy(binary, ascii, sizeof(*binary));
1531
1532 /* Find command by matching typecookie and command number */
1533 for (c = here->type->cmdlist;
1534 c != NULL && c->name != NULL; c++) {
1535 if (binary->header.typecookie == c->cookie
1536 && binary->header.cmd == c->cmd)
1537 break;
1538 }
1539 if (c == NULL || c->name == NULL) {
1540 for (c = ng_generic_cmds; c->name != NULL; c++) {
1541 if (binary->header.typecookie == c->cookie
1542 && binary->header.cmd == c->cmd)
1543 break;
1544 }
1545 if (c->name == NULL) {
1546 kfree(rp, M_NETGRAPH);
1547 error = ENOSYS;
1548 break;
1549 }
1550 }
1551
1552 /* Convert command name to ASCII */
1553 ksnprintf(ascii->header.cmdstr, sizeof(ascii->header.cmdstr),
1554 "%s", c->name);
1555
1556 /* Convert command arguments to ASCII */
1557 argstype = (binary->header.flags & NGF_RESP) ?
1558 c->respType : c->mesgType;
1559 if (argstype == NULL)
1560 *ascii->data = '\0';
1561 else {
1562 if ((error = ng_unparse(argstype,
1563 (u_char *)binary->data,
1564 ascii->data, bufSize)) != 0) {
1565 kfree(rp, M_NETGRAPH);
1566 break;
1567 }
1568 }
1569
1570 /* Return the result as struct ng_mesg plus ASCII string */
1571 bufSize = strlen(ascii->data) + 1;
1572 ascii->header.arglen = bufSize;
1573 rp->header.arglen = sizeof(*ascii) + bufSize;
1574 *resp = rp;
1575 break;
1576 }
1577
1578 case NGM_ASCII2BINARY:
1579 {
1580 int bufSize = 2000; /* XXX hard coded constant */
1581 const struct ng_cmdlist *c;
1582 const struct ng_parse_type *argstype;
1583 struct ng_mesg *rp, *ascii, *binary;
1584 int off = 0;
1585
1586 /* Data area must contain at least a struct ng_mesg + '\0' */
1587 ascii = (struct ng_mesg *)msg->data;
1588 if (msg->header.arglen < sizeof(*ascii) + 1
1589 || ascii->header.arglen < 1
1590 || msg->header.arglen
1591 < sizeof(*ascii) + ascii->header.arglen) {
1592 error = EINVAL;
1593 break;
1594 }
1595 ascii->data[ascii->header.arglen - 1] = '\0';
1596
1597 /* Get a response message with lots of room */
1598 NG_MKRESPONSE(rp, msg, sizeof(*binary) + bufSize, M_NOWAIT);
1599 if (rp == NULL) {
1600 error = ENOMEM;
1601 break;
1602 }
1603 binary = (struct ng_mesg *)rp->data;
1604
1605 /* Copy ASCII message header to response message payload */
1606 bcopy(ascii, binary, sizeof(*ascii));
1607
1608 /* Find command by matching ASCII command string */
1609 for (c = here->type->cmdlist;
1610 c != NULL && c->name != NULL; c++) {
1611 if (strcmp(ascii->header.cmdstr, c->name) == 0)
1612 break;
1613 }
1614 if (c == NULL || c->name == NULL) {
1615 for (c = ng_generic_cmds; c->name != NULL; c++) {
1616 if (strcmp(ascii->header.cmdstr, c->name) == 0)
1617 break;
1618 }
1619 if (c->name == NULL) {
1620 kfree(rp, M_NETGRAPH);
1621 error = ENOSYS;
1622 break;
1623 }
1624 }
1625
1626 /* Convert command name to binary */
1627 binary->header.cmd = c->cmd;
1628 binary->header.typecookie = c->cookie;
1629
1630 /* Convert command arguments to binary */
1631 argstype = (binary->header.flags & NGF_RESP) ?
1632 c->respType : c->mesgType;
1633 if (argstype == NULL)
1634 bufSize = 0;
1635 else {
1636 if ((error = ng_parse(argstype, ascii->data,
1637 &off, (u_char *)binary->data, &bufSize)) != 0) {
1638 kfree(rp, M_NETGRAPH);
1639 break;
1640 }
1641 }
1642
1643 /* Return the result */
1644 binary->header.arglen = bufSize;
1645 rp->header.arglen = sizeof(*binary) + bufSize;
1646 *resp = rp;
1647 break;
1648 }
1649
1650 case NGM_TEXT_CONFIG:
1651 case NGM_TEXT_STATUS:
1652 /*
1653 * This one is tricky as it passes the command down to the
1654 * actual node, even though it is a generic type command.
1655 * This means we must assume that the msg is already freed
1656 * when control passes back to us.
1657 */
1658 if (resp == NULL) {
1659 error = EINVAL;
1660 break;
1661 }
1662 if (here->type->rcvmsg != NULL)
1663 return((*here->type->rcvmsg)(here, msg, retaddr, resp));
1664 /* Fall through if rcvmsg not supported */
1665 default:
1666 TRAP_ERROR;
1667 error = EINVAL;
1668 }
1669 kfree(msg, M_NETGRAPH);
1670 return (error);
1671 }
1672
1673 /*
1674 * Send a data packet to a node. If the recipient has no
1675 * 'receive data' method, then silently discard the packet.
1676 */
1677 int
ng_send_data(hook_p hook,struct mbuf * m,meta_p meta)1678 ng_send_data(hook_p hook, struct mbuf *m, meta_p meta)
1679 {
1680 int (*rcvdata)(hook_p, struct mbuf *, meta_p);
1681 int error;
1682
1683 CHECK_DATA_MBUF(m);
1684 if (hook && (hook->flags & HK_INVALID) == 0) {
1685 rcvdata = hook->peer->node->type->rcvdata;
1686 if (rcvdata != NULL)
1687 error = (*rcvdata)(hook->peer, m, meta);
1688 else {
1689 error = 0;
1690 NG_FREE_DATA(m, meta);
1691 }
1692 } else {
1693 TRAP_ERROR;
1694 error = ENOTCONN;
1695 NG_FREE_DATA(m, meta);
1696 }
1697 return (error);
1698 }
1699
1700 /*
1701 * Send a queued data packet to a node. If the recipient has no
1702 * 'receive queued data' method, then try the 'receive data' method above.
1703 */
1704 int
ng_send_dataq(hook_p hook,struct mbuf * m,meta_p meta)1705 ng_send_dataq(hook_p hook, struct mbuf *m, meta_p meta)
1706 {
1707 int (*rcvdataq)(hook_p, struct mbuf *, meta_p);
1708 int error;
1709
1710 CHECK_DATA_MBUF(m);
1711 if (hook && (hook->flags & HK_INVALID) == 0) {
1712 rcvdataq = hook->peer->node->type->rcvdataq;
1713 if (rcvdataq != NULL)
1714 error = (*rcvdataq)(hook->peer, m, meta);
1715 else {
1716 error = ng_send_data(hook, m, meta);
1717 }
1718 } else {
1719 TRAP_ERROR;
1720 error = ENOTCONN;
1721 NG_FREE_DATA(m, meta);
1722 }
1723 return (error);
1724 }
1725
1726 /*
1727 * Copy a 'meta'.
1728 *
1729 * Returns new meta, or NULL if original meta is NULL or ENOMEM.
1730 */
1731 meta_p
ng_copy_meta(meta_p meta)1732 ng_copy_meta(meta_p meta)
1733 {
1734 meta_p meta2;
1735
1736 if (meta == NULL)
1737 return (NULL);
1738 meta2 = kmalloc(meta->used_len, M_NETGRAPH, M_NOWAIT);
1739 if (meta2 == NULL)
1740 return (NULL);
1741 meta2->allocated_len = meta->used_len;
1742 bcopy(meta, meta2, meta->used_len);
1743 return (meta2);
1744 }
1745
1746 /************************************************************************
1747 Module routines
1748 ************************************************************************/
1749
1750 /*
1751 * Handle the loading/unloading of a netgraph node type module
1752 */
1753 int
ng_mod_event(module_t mod,int event,void * data)1754 ng_mod_event(module_t mod, int event, void *data)
1755 {
1756 struct ng_type *const type = data;
1757 int error = 0;
1758
1759 switch (event) {
1760 case MOD_LOAD:
1761
1762 /* Register new netgraph node type */
1763 crit_enter();
1764 if ((error = ng_newtype(type)) != 0) {
1765 crit_exit();
1766 break;
1767 }
1768
1769 /* Call type specific code */
1770 if (type->mod_event != NULL)
1771 if ((error = (*type->mod_event)(mod, event, data))) {
1772 type->refs--; /* undo it */
1773 LIST_REMOVE(type, types);
1774 }
1775 crit_exit();
1776 break;
1777
1778 case MOD_UNLOAD:
1779 crit_enter();
1780 if (type->refs > 1) { /* make sure no nodes exist! */
1781 error = EBUSY;
1782 } else {
1783 if (type->refs == 0) {
1784 /* failed load, nothing to undo */
1785 crit_exit();
1786 break;
1787 }
1788 if (type->mod_event != NULL) { /* check with type */
1789 error = (*type->mod_event)(mod, event, data);
1790 if (error != 0) { /* type refuses.. */
1791 crit_exit();
1792 break;
1793 }
1794 }
1795 LIST_REMOVE(type, types);
1796 }
1797 crit_exit();
1798 break;
1799
1800 default:
1801 if (type->mod_event != NULL)
1802 error = (*type->mod_event)(mod, event, data);
1803 else
1804 error = 0; /* XXX ? */
1805 break;
1806 }
1807 return (error);
1808 }
1809
1810 /*
1811 * Handle loading and unloading for this code.
1812 * The only thing we need to link into is the NETISR strucure.
1813 */
1814 static int
ngb_mod_event(module_t mod,int event,void * data)1815 ngb_mod_event(module_t mod, int event, void *data)
1816 {
1817 int error = 0;
1818
1819 switch (event) {
1820 case MOD_LOAD:
1821 /* Register line discipline */
1822 crit_enter();
1823 netisr_register(NETISR_NETGRAPH, ngintr, NULL);
1824 crit_exit();
1825 break;
1826 case MOD_UNLOAD:
1827 /* You cant unload it because an interface may be using it. */
1828 error = EBUSY;
1829 break;
1830 default:
1831 error = EOPNOTSUPP;
1832 break;
1833 }
1834 return (error);
1835 }
1836
1837 static moduledata_t netgraph_mod = {
1838 "netgraph",
1839 ngb_mod_event,
1840 (NULL)
1841 };
1842 DECLARE_MODULE(netgraph, netgraph_mod, SI_SUB_DRIVERS, SI_ORDER_MIDDLE);
1843 SYSCTL_NODE(_net, OID_AUTO, graph, CTLFLAG_RW, 0, "netgraph Family");
1844 SYSCTL_INT(_net_graph, OID_AUTO, abi_version, CTLFLAG_RD, 0, NG_ABI_VERSION,"");
1845 SYSCTL_INT(_net_graph, OID_AUTO, msg_version, CTLFLAG_RD, 0, NG_VERSION, "");
1846
1847 /************************************************************************
1848 Queueing routines
1849 ************************************************************************/
1850
1851 /* The structure for queueing across ISR switches */
1852 struct ng_queue_entry {
1853 u_long flags;
1854 struct ng_queue_entry *next;
1855 union {
1856 struct {
1857 hook_p da_hook; /* target hook */
1858 struct mbuf *da_m;
1859 meta_p da_meta;
1860 } data;
1861 struct {
1862 struct ng_mesg *msg_msg;
1863 node_p msg_node;
1864 void *msg_retaddr;
1865 } msg;
1866 } body;
1867 };
1868 #define NGQF_DATA 0x01 /* the queue element is data */
1869 #define NGQF_MESG 0x02 /* the queue element is a message */
1870
1871 static struct ng_queue_entry *ngqbase; /* items to be unqueued */
1872 static struct ng_queue_entry *ngqlast; /* last item queued */
1873 static const int ngqroom = 256; /* max items to queue */
1874 static int ngqsize; /* number of items in queue */
1875
1876 static struct ng_queue_entry *ngqfree; /* free ones */
1877 static const int ngqfreemax = 256;/* cache at most this many */
1878 static int ngqfreesize; /* number of cached entries */
1879
1880 /*
1881 * Get a queue entry
1882 */
1883 static struct ng_queue_entry *
ng_getqblk(void)1884 ng_getqblk(void)
1885 {
1886 struct ng_queue_entry *q;
1887
1888 /* Could be guarding against tty ints or whatever */
1889 crit_enter();
1890
1891 /* Try get a cached queue block, or else allocate a new one */
1892 if ((q = ngqfree) == NULL) {
1893 crit_exit();
1894 if (ngqsize < ngqroom) { /* don't worry about races */
1895 q = kmalloc(sizeof(*q), M_NETGRAPH, M_NOWAIT);
1896 }
1897 } else {
1898 ngqfree = q->next;
1899 ngqfreesize--;
1900 crit_exit();
1901 }
1902 return (q);
1903 }
1904
1905 /*
1906 * Release a queue entry
1907 */
1908 #define RETURN_QBLK(q) \
1909 do { \
1910 if (ngqfreesize < ngqfreemax) { /* don't worry about races */ \
1911 crit_enter(); \
1912 (q)->next = ngqfree; \
1913 ngqfree = (q); \
1914 ngqfreesize++; \
1915 crit_exit(); \
1916 } else { \
1917 kfree((q), M_NETGRAPH); \
1918 } \
1919 } while (0)
1920
1921 /*
1922 * Running at a raised (but we don't know which) processor priority level,
1923 * put the data onto a queue to be picked up by another PPL (probably splnet)
1924 */
1925 int
ng_queue_data(hook_p hook,struct mbuf * m,meta_p meta)1926 ng_queue_data(hook_p hook, struct mbuf *m, meta_p meta)
1927 {
1928 struct ng_queue_entry *q;
1929
1930 if (hook == NULL) {
1931 NG_FREE_DATA(m, meta);
1932 return (0);
1933 }
1934 if ((q = ng_getqblk()) == NULL) {
1935 NG_FREE_DATA(m, meta);
1936 return (ENOBUFS);
1937 }
1938
1939 /* Fill out the contents */
1940 q->flags = NGQF_DATA;
1941 q->next = NULL;
1942 q->body.data.da_hook = hook;
1943 q->body.data.da_m = m;
1944 q->body.data.da_meta = meta;
1945 crit_enter(); /* protect refs and queue */
1946 hook->refs++; /* don't let it go away while on the queue */
1947
1948 /* Put it on the queue */
1949 if (ngqbase) {
1950 ngqlast->next = q;
1951 } else {
1952 ngqbase = q;
1953 }
1954 ngqlast = q;
1955 ngqsize++;
1956 crit_exit();
1957
1958 /* Schedule software interrupt to handle it later */
1959 schednetisr(NETISR_NETGRAPH);
1960 return (0);
1961 }
1962
1963 /*
1964 * Running at a raised (but we don't know which) processor priority level,
1965 * put the msg onto a queue to be picked up by another PPL (probably splnet)
1966 */
1967 int
ng_queue_msg(node_p here,struct ng_mesg * msg,const char * address)1968 ng_queue_msg(node_p here, struct ng_mesg *msg, const char *address)
1969 {
1970 struct ng_queue_entry *q;
1971 node_p dest = NULL;
1972 char *retaddr = NULL;
1973 int error;
1974
1975 /* Find the target node. */
1976 error = ng_path2node(here, address, &dest, &retaddr);
1977 if (error) {
1978 kfree(msg, M_NETGRAPH);
1979 return (error);
1980 }
1981 if ((q = ng_getqblk()) == NULL) {
1982 kfree(msg, M_NETGRAPH);
1983 if (retaddr)
1984 kfree(retaddr, M_NETGRAPH);
1985 return (ENOBUFS);
1986 }
1987
1988 /* Fill out the contents */
1989 q->flags = NGQF_MESG;
1990 q->next = NULL;
1991 q->body.msg.msg_node = dest;
1992 q->body.msg.msg_msg = msg;
1993 q->body.msg.msg_retaddr = retaddr;
1994 crit_enter(); /* protect refs and queue */
1995 dest->refs++; /* don't let it go away while on the queue */
1996
1997 /* Put it on the queue */
1998 if (ngqbase) {
1999 ngqlast->next = q;
2000 } else {
2001 ngqbase = q;
2002 }
2003 ngqlast = q;
2004 ngqsize++;
2005 crit_exit();
2006
2007 /* Schedule software interrupt to handle it later */
2008 schednetisr(NETISR_NETGRAPH);
2009 return (0);
2010 }
2011
2012 /*
2013 * Pick an item off the queue, process it, and dispose of the queue entry.
2014 */
2015 static void
ngintr(netmsg_t pmsg)2016 ngintr(netmsg_t pmsg)
2017 {
2018 hook_p hook;
2019 struct mbuf *m;
2020 struct ng_queue_entry *ngq;
2021 meta_p meta;
2022 void *retaddr;
2023 struct ng_mesg *msg;
2024 node_p node;
2025 int error = 0;
2026
2027 /*
2028 * Packets are never sent to this netisr so the message must always
2029 * be replied. Interlock processing and notification by replying
2030 * the message first.
2031 */
2032 lwkt_replymsg(&pmsg->lmsg, 0);
2033
2034 get_mplock();
2035
2036 while (1) {
2037 crit_enter();
2038 if ((ngq = ngqbase)) {
2039 ngqbase = ngq->next;
2040 ngqsize--;
2041 }
2042 crit_exit();
2043 if (ngq == NULL)
2044 goto out;
2045 switch (ngq->flags) {
2046 case NGQF_DATA:
2047 hook = ngq->body.data.da_hook;
2048 m = ngq->body.data.da_m;
2049 meta = ngq->body.data.da_meta;
2050 RETURN_QBLK(ngq);
2051 NG_SEND_DATAQ(error, hook, m, meta);
2052 ng_unref_hook(hook);
2053 break;
2054 case NGQF_MESG:
2055 node = ngq->body.msg.msg_node;
2056 msg = ngq->body.msg.msg_msg;
2057 retaddr = ngq->body.msg.msg_retaddr;
2058 RETURN_QBLK(ngq);
2059 if (node->flags & NG_INVALID) {
2060 kfree(msg, M_NETGRAPH);
2061 } else {
2062 CALL_MSG_HANDLER(error, node, msg,
2063 retaddr, NULL);
2064 }
2065 ng_unref(node);
2066 if (retaddr)
2067 kfree(retaddr, M_NETGRAPH);
2068 break;
2069 default:
2070 RETURN_QBLK(ngq);
2071 }
2072 }
2073 out:
2074 rel_mplock();
2075 }
2076
2077
2078