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