The Design and Implementation of the FreeBSD Operating System, Second Edition
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FreeBSD/Linux Kernel Cross Reference
sys/netgraph/netgraph.h

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    1 /*
    2  * netgraph.h
    3  */
    4 
    5 /*-
    6  * Copyright (c) 1996-1999 Whistle Communications, Inc.
    7  * All rights reserved.
    8  * 
    9  * Subject to the following obligations and disclaimer of warranty, use and
   10  * redistribution of this software, in source or object code forms, with or
   11  * without modifications are expressly permitted by Whistle Communications;
   12  * provided, however, that:
   13  * 1. Any and all reproductions of the source or object code must include the
   14  *    copyright notice above and the following disclaimer of warranties; and
   15  * 2. No rights are granted, in any manner or form, to use Whistle
   16  *    Communications, Inc. trademarks, including the mark "WHISTLE
   17  *    COMMUNICATIONS" on advertising, endorsements, or otherwise except as
   18  *    such appears in the above copyright notice or in the software.
   19  * 
   20  * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
   21  * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
   22  * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
   23  * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
   24  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
   25  * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
   26  * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
   27  * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
   28  * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
   29  * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
   30  * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
   31  * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
   32  * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
   33  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
   34  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
   35  * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
   36  * OF SUCH DAMAGE.
   37  *
   38  * Author: Julian Elischer <julian@freebsd.org>
   39  *
   40  * $FreeBSD: releng/6.1/sys/netgraph/netgraph.h 154614 2006-01-21 10:00:51Z glebius $
   41  * $Whistle: netgraph.h,v 1.29 1999/11/01 07:56:13 julian Exp $
   42  */
   43 
   44 #ifndef _NETGRAPH_NETGRAPH_H_
   45 #define _NETGRAPH_NETGRAPH_H_
   46 
   47 #ifndef _KERNEL
   48 #error "This file should not be included in user level programs"
   49 #endif
   50 
   51 #include <sys/queue.h>
   52 #include <sys/lock.h>
   53 #include <sys/malloc.h>
   54 #include <sys/module.h>
   55 #include <sys/mutex.h>
   56 
   57 #include "opt_netgraph.h"
   58 
   59 /* debugging options */
   60 #define NG_SEPARATE_MALLOC      /* make modules use their own malloc types */
   61 
   62 /*
   63  * This defines the in-kernel binary interface version.
   64  * It is possible to change this but leave the external message
   65  * API the same. Each type also has it's own cookies for versioning as well.
   66  * Change it for NETGRAPH_DEBUG version so we cannot mix debug and non debug
   67  * modules.
   68  */
   69 #define _NG_ABI_VERSION 11
   70 #ifdef  NETGRAPH_DEBUG /*----------------------------------------------*/
   71 #define NG_ABI_VERSION  (_NG_ABI_VERSION + 0x10000)
   72 #else   /* NETGRAPH_DEBUG */ /*----------------------------------------------*/
   73 #define NG_ABI_VERSION  _NG_ABI_VERSION
   74 #endif  /* NETGRAPH_DEBUG */ /*----------------------------------------------*/
   75 
   76 
   77 /*
   78  * Forward references for the basic structures so we can
   79  * define the typedefs and use them in the structures themselves.
   80  */
   81 struct ng_hook ;
   82 struct ng_node ;
   83 struct ng_item ;
   84 typedef struct ng_item *item_p;
   85 typedef struct ng_node *node_p;
   86 typedef struct ng_hook *hook_p;
   87 
   88 /* node method definitions */
   89 typedef int     ng_constructor_t(node_p node);
   90 typedef int     ng_close_t(node_p node);
   91 typedef int     ng_shutdown_t(node_p node);
   92 typedef int     ng_newhook_t(node_p node, hook_p hook, const char *name);
   93 typedef hook_p  ng_findhook_t(node_p node, const char *name);
   94 typedef int     ng_connect_t(hook_p hook);
   95 typedef int     ng_rcvmsg_t(node_p node, item_p item, hook_p lasthook);
   96 typedef int     ng_rcvdata_t(hook_p hook, item_p item);
   97 typedef int     ng_disconnect_t(hook_p hook);
   98 typedef int     ng_rcvitem (node_p node, hook_p hook, item_p item);
   99 
  100 /***********************************************************************
  101  ***************** Hook Structure and Methods **************************
  102  ***********************************************************************
  103  *
  104  * Structure of a hook
  105  */
  106 struct ng_hook {
  107         char    hk_name[NG_HOOKSIZ];    /* what this node knows this link as */
  108         void   *hk_private;             /* node dependant ID for this hook */
  109         int     hk_flags;               /* info about this hook/link */
  110         int     hk_refs;                /* dont actually free this till 0 */
  111         int     hk_type;                /* tbd: hook data link type */
  112         struct  ng_hook *hk_peer;       /* the other end of this link */
  113         struct  ng_node *hk_node;       /* The node this hook is attached to */
  114         LIST_ENTRY(ng_hook) hk_hooks;   /* linked list of all hooks on node */
  115         ng_rcvmsg_t     *hk_rcvmsg;     /* control messages come here */
  116         ng_rcvdata_t    *hk_rcvdata;    /* data comes here */
  117 #ifdef  NETGRAPH_DEBUG /*----------------------------------------------*/
  118 #define HK_MAGIC 0x78573011
  119         int     hk_magic;
  120         char    *lastfile;
  121         int     lastline;
  122         SLIST_ENTRY(ng_hook)      hk_all;               /* all existing items */
  123 #endif  /* NETGRAPH_DEBUG */ /*----------------------------------------------*/
  124 };
  125 /* Flags for a hook */
  126 #define HK_INVALID              0x0001  /* don't trust it! */
  127 #define HK_QUEUE                0x0002  /* queue for later delivery */
  128 #define HK_FORCE_WRITER         0x0004  /* Incoming data queued as a writer */
  129 #define HK_DEAD                 0x0008  /* This is the dead hook.. don't free */
  130 
  131 /*
  132  * Public Methods for hook
  133  * If you can't do it with these you probably shouldn;t be doing it.
  134  */
  135 void ng_unref_hook(hook_p hook); /* don't move this */
  136 #define _NG_HOOK_REF(hook)      atomic_add_int(&(hook)->hk_refs, 1)
  137 #define _NG_HOOK_NAME(hook)     ((hook)->hk_name)
  138 #define _NG_HOOK_UNREF(hook)    ng_unref_hook(hook)
  139 #define _NG_HOOK_SET_PRIVATE(hook, val) do {(hook)->hk_private = val;} while (0)
  140 #define _NG_HOOK_SET_RCVMSG(hook, val)  do {(hook)->hk_rcvmsg = val;} while (0)
  141 #define _NG_HOOK_SET_RCVDATA(hook, val) do {(hook)->hk_rcvdata = val;} while (0)
  142 #define _NG_HOOK_PRIVATE(hook)  ((hook)->hk_private)
  143 #define _NG_HOOK_NOT_VALID(hook)        ((hook)->hk_flags & HK_INVALID)
  144 #define _NG_HOOK_IS_VALID(hook) (!((hook)->hk_flags & HK_INVALID))
  145 #define _NG_HOOK_NODE(hook)     ((hook)->hk_node) /* only rvalue! */
  146 #define _NG_HOOK_PEER(hook)     ((hook)->hk_peer) /* only rvalue! */
  147 #define _NG_HOOK_FORCE_WRITER(hook)                             \
  148                 do { hook->hk_flags |= HK_FORCE_WRITER; } while (0)
  149 #define _NG_HOOK_FORCE_QUEUE(hook) do { hook->hk_flags |= HK_QUEUE; } while (0)
  150 
  151 /* Some shortcuts */
  152 #define NG_PEER_NODE(hook)      NG_HOOK_NODE(NG_HOOK_PEER(hook))
  153 #define NG_PEER_HOOK_NAME(hook) NG_HOOK_NAME(NG_HOOK_PEER(hook))
  154 #define NG_PEER_NODE_NAME(hook) NG_NODE_NAME(NG_PEER_NODE(hook))
  155 
  156 #ifdef  NETGRAPH_DEBUG /*----------------------------------------------*/
  157 #define _NN_ __FILE__,__LINE__
  158 void    dumphook (hook_p hook, char *file, int line);
  159 static __inline void    _chkhook(hook_p hook, char *file, int line);
  160 static __inline void    _ng_hook_ref(hook_p hook, char * file, int line);
  161 static __inline char *  _ng_hook_name(hook_p hook, char * file, int line);
  162 static __inline void    _ng_hook_unref(hook_p hook, char * file, int line);
  163 static __inline void    _ng_hook_set_private(hook_p hook,
  164                                 void * val, char * file, int line);
  165 static __inline void    _ng_hook_set_rcvmsg(hook_p hook,
  166                                 ng_rcvmsg_t *val, char * file, int line);
  167 static __inline void    _ng_hook_set_rcvdata(hook_p hook,
  168                                 ng_rcvdata_t *val, char * file, int line);
  169 static __inline void *  _ng_hook_private(hook_p hook, char * file, int line);
  170 static __inline int     _ng_hook_not_valid(hook_p hook, char * file, int line);
  171 static __inline int     _ng_hook_is_valid(hook_p hook, char * file, int line);
  172 static __inline node_p  _ng_hook_node(hook_p hook, char * file, int line);
  173 static __inline hook_p  _ng_hook_peer(hook_p hook, char * file, int line);
  174 static __inline void    _ng_hook_force_writer(hook_p hook, char * file,
  175                                         int line);
  176 static __inline void    _ng_hook_force_queue(hook_p hook, char * file, int line);
  177 
  178 static __inline void
  179 _chkhook(hook_p hook, char *file, int line)
  180 {
  181         if (hook->hk_magic != HK_MAGIC) {
  182                 printf("Accessing freed hook ");
  183                 dumphook(hook, file, line);
  184         }
  185         hook->lastline = line;
  186         hook->lastfile = file;
  187 }
  188 
  189 static __inline void
  190 _ng_hook_ref(hook_p hook, char * file, int line)
  191 {
  192         _chkhook(hook, file, line);
  193         _NG_HOOK_REF(hook);
  194 }
  195 
  196 static __inline char *
  197 _ng_hook_name(hook_p hook, char * file, int line)
  198 {
  199         _chkhook(hook, file, line);
  200         return (_NG_HOOK_NAME(hook));
  201 }
  202 
  203 static __inline void
  204 _ng_hook_unref(hook_p hook, char * file, int line)
  205 {
  206         _chkhook(hook, file, line);
  207         _NG_HOOK_UNREF(hook);
  208 }
  209 
  210 static __inline void
  211 _ng_hook_set_private(hook_p hook, void *val, char * file, int line)
  212 {
  213         _chkhook(hook, file, line);
  214         _NG_HOOK_SET_PRIVATE(hook, val);
  215 }
  216 
  217 static __inline void
  218 _ng_hook_set_rcvmsg(hook_p hook, ng_rcvmsg_t *val, char * file, int line)
  219 {
  220         _chkhook(hook, file, line);
  221         _NG_HOOK_SET_RCVMSG(hook, val);
  222 }
  223 
  224 static __inline void
  225 _ng_hook_set_rcvdata(hook_p hook, ng_rcvdata_t *val, char * file, int line)
  226 {
  227         _chkhook(hook, file, line);
  228         _NG_HOOK_SET_RCVDATA(hook, val);
  229 }
  230 
  231 static __inline void *
  232 _ng_hook_private(hook_p hook, char * file, int line)
  233 {
  234         _chkhook(hook, file, line);
  235         return (_NG_HOOK_PRIVATE(hook));
  236 }
  237 
  238 static __inline int
  239 _ng_hook_not_valid(hook_p hook, char * file, int line)
  240 {
  241         _chkhook(hook, file, line);
  242         return (_NG_HOOK_NOT_VALID(hook));
  243 }
  244 
  245 static __inline int
  246 _ng_hook_is_valid(hook_p hook, char * file, int line)
  247 {
  248         _chkhook(hook, file, line);
  249         return (_NG_HOOK_IS_VALID(hook));
  250 }
  251 
  252 static __inline node_p
  253 _ng_hook_node(hook_p hook, char * file, int line)
  254 {
  255         _chkhook(hook, file, line);
  256         return (_NG_HOOK_NODE(hook));
  257 }
  258 
  259 static __inline hook_p
  260 _ng_hook_peer(hook_p hook, char * file, int line)
  261 {
  262         _chkhook(hook, file, line);
  263         return (_NG_HOOK_PEER(hook));
  264 }
  265 
  266 static __inline void
  267 _ng_hook_force_writer(hook_p hook, char * file, int line)
  268 {
  269         _chkhook(hook, file, line);
  270         _NG_HOOK_FORCE_WRITER(hook);
  271 }
  272 
  273 static __inline void
  274 _ng_hook_force_queue(hook_p hook, char * file, int line)
  275 {
  276         _chkhook(hook, file, line);
  277         _NG_HOOK_FORCE_QUEUE(hook);
  278 }
  279 
  280 
  281 #define NG_HOOK_REF(hook)               _ng_hook_ref(hook, _NN_)
  282 #define NG_HOOK_NAME(hook)              _ng_hook_name(hook, _NN_)
  283 #define NG_HOOK_UNREF(hook)             _ng_hook_unref(hook, _NN_)
  284 #define NG_HOOK_SET_PRIVATE(hook, val)  _ng_hook_set_private(hook, val, _NN_)
  285 #define NG_HOOK_SET_RCVMSG(hook, val)   _ng_hook_set_rcvmsg(hook, val, _NN_)
  286 #define NG_HOOK_SET_RCVDATA(hook, val)  _ng_hook_set_rcvdata(hook, val, _NN_)
  287 #define NG_HOOK_PRIVATE(hook)           _ng_hook_private(hook, _NN_)
  288 #define NG_HOOK_NOT_VALID(hook)         _ng_hook_not_valid(hook, _NN_)
  289 #define NG_HOOK_IS_VALID(hook)          _ng_hook_is_valid(hook, _NN_)
  290 #define NG_HOOK_NODE(hook)              _ng_hook_node(hook, _NN_)
  291 #define NG_HOOK_PEER(hook)              _ng_hook_peer(hook, _NN_)
  292 #define NG_HOOK_FORCE_WRITER(hook)      _ng_hook_force_writer(hook, _NN_)
  293 #define NG_HOOK_FORCE_QUEUE(hook)       _ng_hook_force_queue(hook, _NN_)
  294 
  295 #else   /* NETGRAPH_DEBUG */ /*----------------------------------------------*/
  296 
  297 #define NG_HOOK_REF(hook)               _NG_HOOK_REF(hook)
  298 #define NG_HOOK_NAME(hook)              _NG_HOOK_NAME(hook)
  299 #define NG_HOOK_UNREF(hook)             _NG_HOOK_UNREF(hook)
  300 #define NG_HOOK_SET_PRIVATE(hook, val)  _NG_HOOK_SET_PRIVATE(hook, val)
  301 #define NG_HOOK_SET_RCVMSG(hook, val)   _NG_HOOK_SET_RCVMSG(hook, val)
  302 #define NG_HOOK_SET_RCVDATA(hook, val)  _NG_HOOK_SET_RCVDATA(hook, val)
  303 #define NG_HOOK_PRIVATE(hook)           _NG_HOOK_PRIVATE(hook)
  304 #define NG_HOOK_NOT_VALID(hook)         _NG_HOOK_NOT_VALID(hook)
  305 #define NG_HOOK_IS_VALID(hook)          _NG_HOOK_IS_VALID(hook)
  306 #define NG_HOOK_NODE(hook)              _NG_HOOK_NODE(hook)
  307 #define NG_HOOK_PEER(hook)              _NG_HOOK_PEER(hook)
  308 #define NG_HOOK_FORCE_WRITER(hook)      _NG_HOOK_FORCE_WRITER(hook)
  309 #define NG_HOOK_FORCE_QUEUE(hook)       _NG_HOOK_FORCE_QUEUE(hook)
  310 
  311 #endif  /* NETGRAPH_DEBUG */ /*----------------------------------------------*/
  312 
  313 /***********************************************************************
  314  ***************** Node Structure and Methods **************************
  315  ***********************************************************************
  316  * Structure of a node
  317  * including the eembedded queue structure.
  318  *
  319  * The structure for queueing Netgraph request items
  320  * embedded in the node structure
  321  */
  322 struct ng_queue {
  323         u_long          q_flags;
  324         struct mtx      q_mtx;
  325         item_p queue;
  326         item_p *last;
  327         struct ng_node *q_node;         /* find the front of the node.. */
  328 };
  329 
  330 struct ng_node {
  331         char    nd_name[NG_NODESIZ];    /* optional globally unique name */
  332         struct  ng_type *nd_type;       /* the installed 'type' */
  333         int     nd_flags;               /* see below for bit definitions */
  334         int     nd_refs;                /* # of references to this node */
  335         int     nd_numhooks;            /* number of hooks */
  336         void   *nd_private;             /* node type dependant node ID */
  337         ng_ID_t nd_ID;                  /* Unique per node */
  338         LIST_HEAD(hooks, ng_hook) nd_hooks;     /* linked list of node hooks */
  339         LIST_ENTRY(ng_node)       nd_nodes;     /* linked list of all nodes */
  340         LIST_ENTRY(ng_node)       nd_idnodes;   /* ID hash collision list */
  341         TAILQ_ENTRY(ng_node)      nd_work;      /* nodes with work to do */
  342         struct  ng_queue          nd_input_queue; /* input queue for locking */
  343 #ifdef  NETGRAPH_DEBUG /*----------------------------------------------*/
  344 #define ND_MAGIC 0x59264837
  345         int     nd_magic;
  346         char    *lastfile;
  347         int     lastline;
  348         SLIST_ENTRY(ng_node)      nd_all;       /* all existing nodes */
  349 #endif  /* NETGRAPH_DEBUG */ /*----------------------------------------------*/
  350 };
  351 
  352 /* Flags for a node */
  353 #define NGF_INVALID     0x00000001      /* free when refs go to 0 */
  354 #define NG_INVALID      NGF_INVALID     /* compat for old code */
  355 #define NGF_WORKQ       0x00000002      /* node is on the work queue */
  356 #define NG_WORKQ        NGF_WORKQ       /* compat for old code */
  357 #define NGF_FORCE_WRITER        0x00000004      /* Never multithread this node */
  358 #define NG_FORCE_WRITER NGF_FORCE_WRITER /* compat for old code */
  359 #define NGF_CLOSING     0x00000008      /* ng_rmnode() at work */
  360 #define NG_CLOSING      NGF_CLOSING     /* compat for old code */
  361 #define NGF_REALLY_DIE  0x00000010      /* "persistent" node is unloading */
  362 #define NG_REALLY_DIE   NGF_REALLY_DIE  /* compat for old code */
  363 #define NGF_TYPE1       0x10000000      /* reserved for type specific storage */
  364 #define NGF_TYPE2       0x20000000      /* reserved for type specific storage */
  365 #define NGF_TYPE3       0x40000000      /* reserved for type specific storage */
  366 #define NGF_TYPE4       0x80000000      /* reserved for type specific storage */
  367 
  368 /*
  369  * Public methods for nodes.
  370  * If you can't do it with these you probably shouldn't be doing it.
  371  */
  372 int     ng_unref_node(node_p node); /* don't move this */
  373 #define _NG_NODE_NAME(node)     ((node)->nd_name + 0)
  374 #define _NG_NODE_HAS_NAME(node) ((node)->nd_name[0] + 0)
  375 #define _NG_NODE_ID(node)       ((node)->nd_ID + 0)
  376 #define _NG_NODE_REF(node)      atomic_add_int(&(node)->nd_refs, 1)
  377 #define _NG_NODE_UNREF(node)    ng_unref_node(node)
  378 #define _NG_NODE_SET_PRIVATE(node, val) do {(node)->nd_private = val;} while (0)
  379 #define _NG_NODE_PRIVATE(node)  ((node)->nd_private)
  380 #define _NG_NODE_IS_VALID(node) (!((node)->nd_flags & NGF_INVALID))
  381 #define _NG_NODE_NOT_VALID(node)        ((node)->nd_flags & NGF_INVALID)
  382 #define _NG_NODE_NUMHOOKS(node) ((node)->nd_numhooks + 0) /* rvalue */
  383 #define _NG_NODE_FORCE_WRITER(node)                                     \
  384         do{ node->nd_flags |= NGF_FORCE_WRITER; }while (0)
  385 #define _NG_NODE_REALLY_DIE(node)                                       \
  386         do{ node->nd_flags |= (NGF_REALLY_DIE|NGF_INVALID); }while (0)
  387 #define _NG_NODE_REVIVE(node) \
  388         do { node->nd_flags &= ~NGF_INVALID; } while (0)
  389 /*
  390  * The hook iterator.
  391  * This macro will call a function of type ng_fn_eachhook for each
  392  * hook attached to the node. If the function returns 0, then the
  393  * iterator will stop and return a pointer to the hook that returned 0.
  394  */
  395 typedef int     ng_fn_eachhook(hook_p hook, void* arg);
  396 #define _NG_NODE_FOREACH_HOOK(node, fn, arg, rethook)                   \
  397         do {                                                            \
  398                 hook_p _hook;                                           \
  399                 (rethook) = NULL;                                       \
  400                 LIST_FOREACH(_hook, &((node)->nd_hooks), hk_hooks) {    \
  401                         if ((fn)(_hook, arg) == 0) {                    \
  402                                 (rethook) = _hook;                      \
  403                                 break;                                  \
  404                         }                                               \
  405                 }                                                       \
  406         } while (0)
  407 
  408 #ifdef  NETGRAPH_DEBUG /*----------------------------------------------*/
  409 void    dumpnode(node_p node, char *file, int line);
  410 static __inline void _chknode(node_p node, char *file, int line);
  411 static __inline char * _ng_node_name(node_p node, char *file, int line);
  412 static __inline int _ng_node_has_name(node_p node, char *file, int line);
  413 static __inline ng_ID_t _ng_node_id(node_p node, char *file, int line);
  414 static __inline void _ng_node_ref(node_p node, char *file, int line);
  415 static __inline int _ng_node_unref(node_p node, char *file, int line);
  416 static __inline void _ng_node_set_private(node_p node, void * val,
  417                                                         char *file, int line);
  418 static __inline void * _ng_node_private(node_p node, char *file, int line);
  419 static __inline int _ng_node_is_valid(node_p node, char *file, int line);
  420 static __inline int _ng_node_not_valid(node_p node, char *file, int line);
  421 static __inline int _ng_node_numhooks(node_p node, char *file, int line);
  422 static __inline void _ng_node_force_writer(node_p node, char *file, int line);
  423 static __inline hook_p _ng_node_foreach_hook(node_p node,
  424                         ng_fn_eachhook *fn, void *arg, char *file, int line);
  425 static __inline void _ng_node_revive(node_p node, char *file, int line);
  426 
  427 static __inline void
  428 _chknode(node_p node, char *file, int line)
  429 {
  430         if (node->nd_magic != ND_MAGIC) {
  431                 printf("Accessing freed node ");
  432                 dumpnode(node, file, line);
  433         }
  434         node->lastline = line;
  435         node->lastfile = file;
  436 }
  437 
  438 static __inline char *
  439 _ng_node_name(node_p node, char *file, int line)
  440 {
  441         _chknode(node, file, line);
  442         return(_NG_NODE_NAME(node));
  443 }
  444 
  445 static __inline int
  446 _ng_node_has_name(node_p node, char *file, int line)
  447 {
  448         _chknode(node, file, line);
  449         return(_NG_NODE_HAS_NAME(node));
  450 }
  451 
  452 static __inline ng_ID_t
  453 _ng_node_id(node_p node, char *file, int line)
  454 {
  455         _chknode(node, file, line);
  456         return(_NG_NODE_ID(node));
  457 }
  458 
  459 static __inline void
  460 _ng_node_ref(node_p node, char *file, int line)
  461 {
  462         _chknode(node, file, line);
  463         _NG_NODE_REF(node);
  464 }
  465 
  466 static __inline int
  467 _ng_node_unref(node_p node, char *file, int line)
  468 {
  469         _chknode(node, file, line);
  470         return (_NG_NODE_UNREF(node));
  471 }
  472 
  473 static __inline void
  474 _ng_node_set_private(node_p node, void * val, char *file, int line)
  475 {
  476         _chknode(node, file, line);
  477         _NG_NODE_SET_PRIVATE(node, val);
  478 }
  479 
  480 static __inline void *
  481 _ng_node_private(node_p node, char *file, int line)
  482 {
  483         _chknode(node, file, line);
  484         return (_NG_NODE_PRIVATE(node));
  485 }
  486 
  487 static __inline int
  488 _ng_node_is_valid(node_p node, char *file, int line)
  489 {
  490         _chknode(node, file, line);
  491         return(_NG_NODE_IS_VALID(node));
  492 }
  493 
  494 static __inline int
  495 _ng_node_not_valid(node_p node, char *file, int line)
  496 {
  497         _chknode(node, file, line);
  498         return(_NG_NODE_NOT_VALID(node));
  499 }
  500 
  501 static __inline int
  502 _ng_node_numhooks(node_p node, char *file, int line)
  503 {
  504         _chknode(node, file, line);
  505         return(_NG_NODE_NUMHOOKS(node));
  506 }
  507 
  508 static __inline void
  509 _ng_node_force_writer(node_p node, char *file, int line)
  510 {
  511         _chknode(node, file, line);
  512         _NG_NODE_FORCE_WRITER(node);
  513 }
  514 
  515 static __inline void
  516 _ng_node_really_die(node_p node, char *file, int line)
  517 {
  518         _chknode(node, file, line);
  519         _NG_NODE_REALLY_DIE(node);
  520 }
  521 
  522 static __inline void
  523 _ng_node_revive(node_p node, char *file, int line)
  524 {
  525         _chknode(node, file, line);
  526         _NG_NODE_REVIVE(node);
  527 }
  528 
  529 static __inline hook_p
  530 _ng_node_foreach_hook(node_p node, ng_fn_eachhook *fn, void *arg,
  531                                                 char *file, int line)
  532 {
  533         hook_p hook;
  534         _chknode(node, file, line);
  535         _NG_NODE_FOREACH_HOOK(node, fn, arg, hook);
  536         return (hook);
  537 }
  538 
  539 #define NG_NODE_NAME(node)              _ng_node_name(node, _NN_)       
  540 #define NG_NODE_HAS_NAME(node)          _ng_node_has_name(node, _NN_)   
  541 #define NG_NODE_ID(node)                _ng_node_id(node, _NN_)
  542 #define NG_NODE_REF(node)               _ng_node_ref(node, _NN_)
  543 #define NG_NODE_UNREF(node)             _ng_node_unref(node, _NN_)
  544 #define NG_NODE_SET_PRIVATE(node, val)  _ng_node_set_private(node, val, _NN_)
  545 #define NG_NODE_PRIVATE(node)           _ng_node_private(node, _NN_)
  546 #define NG_NODE_IS_VALID(node)          _ng_node_is_valid(node, _NN_)
  547 #define NG_NODE_NOT_VALID(node)         _ng_node_not_valid(node, _NN_)
  548 #define NG_NODE_FORCE_WRITER(node)      _ng_node_force_writer(node, _NN_)
  549 #define NG_NODE_REALLY_DIE(node)        _ng_node_really_die(node, _NN_)
  550 #define NG_NODE_NUMHOOKS(node)          _ng_node_numhooks(node, _NN_)
  551 #define NG_NODE_REVIVE(node)            _ng_node_revive(node, _NN_)
  552 #define NG_NODE_FOREACH_HOOK(node, fn, arg, rethook)                          \
  553         do {                                                                  \
  554                 rethook = _ng_node_foreach_hook(node, fn, (void *)arg, _NN_); \
  555         } while (0)
  556 
  557 #else   /* NETGRAPH_DEBUG */ /*----------------------------------------------*/
  558 
  559 #define NG_NODE_NAME(node)              _NG_NODE_NAME(node)     
  560 #define NG_NODE_HAS_NAME(node)          _NG_NODE_HAS_NAME(node) 
  561 #define NG_NODE_ID(node)                _NG_NODE_ID(node)       
  562 #define NG_NODE_REF(node)               _NG_NODE_REF(node)      
  563 #define NG_NODE_UNREF(node)             _NG_NODE_UNREF(node)    
  564 #define NG_NODE_SET_PRIVATE(node, val)  _NG_NODE_SET_PRIVATE(node, val) 
  565 #define NG_NODE_PRIVATE(node)           _NG_NODE_PRIVATE(node)  
  566 #define NG_NODE_IS_VALID(node)          _NG_NODE_IS_VALID(node) 
  567 #define NG_NODE_NOT_VALID(node)         _NG_NODE_NOT_VALID(node)        
  568 #define NG_NODE_FORCE_WRITER(node)      _NG_NODE_FORCE_WRITER(node)
  569 #define NG_NODE_REALLY_DIE(node)        _NG_NODE_REALLY_DIE(node)
  570 #define NG_NODE_NUMHOOKS(node)          _NG_NODE_NUMHOOKS(node) 
  571 #define NG_NODE_REVIVE(node)            _NG_NODE_REVIVE(node)
  572 #define NG_NODE_FOREACH_HOOK(node, fn, arg, rethook)                    \
  573                 _NG_NODE_FOREACH_HOOK(node, fn, arg, rethook)
  574 #endif  /* NETGRAPH_DEBUG */ /*----------------------------------------------*/
  575 
  576 /***********************************************************************
  577  ************* Node Queue and Item Structures and Methods **************
  578  ***********************************************************************
  579  *
  580  */
  581 typedef void    ng_item_fn(node_p node, hook_p hook, void *arg1, int arg2);
  582 typedef void    ng_apply_t(void *context, int error);
  583 struct ng_item {
  584         u_long  el_flags;
  585         item_p  el_next;
  586         node_p  el_dest; /* The node it will be applied against (or NULL) */
  587         hook_p  el_hook; /* Entering hook. Optional in Control messages */
  588         union {
  589                 struct mbuf     *da_m;
  590                 struct {
  591                         struct ng_mesg  *msg_msg;
  592                         ng_ID_t         msg_retaddr;
  593                 } msg;
  594                 struct {
  595                         ng_item_fn      *fn_fn;
  596                         void            *fn_arg1;
  597                         int             fn_arg2;
  598                 } fn;
  599         } body;
  600         /*
  601          * Optional callback called when item is being applied,
  602          * and its context.
  603          */
  604         ng_apply_t      *apply;
  605         void            *context;
  606 #ifdef  NETGRAPH_DEBUG /*----------------------------------------------*/
  607         char *lastfile;
  608         int  lastline;
  609         TAILQ_ENTRY(ng_item)      all;          /* all existing items */
  610 #endif  /* NETGRAPH_DEBUG */ /*----------------------------------------------*/
  611 };
  612 
  613 #define NGQF_TYPE       0x03            /* MASK of content definition */
  614 #define NGQF_MESG       0x00            /* the queue element is a message */
  615 #define NGQF_DATA       0x01            /* the queue element is data */
  616 #define NGQF_FN         0x02            /* the queue element is a function */
  617 #define NGQF_UNDEF      0x03            /* UNDEFINED */
  618 
  619 #define NGQF_RW         0x04            /* MASK for wanted queue mode */
  620 #define NGQF_READER     0x04            /* wants to be a reader */
  621 #define NGQF_WRITER     0x00            /* wants to be a writer */
  622 
  623 #define NGQF_QMODE      0x08            /* MASK for how it was queued */
  624 #define NGQF_QREADER    0x08            /* was queued as a reader */
  625 #define NGQF_QWRITER    0x00            /* was queued as a writer */
  626 
  627 /*
  628  * Get the mbuf (etc) out of an item.
  629  * Sets the value in the item to NULL in case we need to call NG_FREE_ITEM()
  630  * with it, (to avoid freeing the things twice).
  631  * If you don't want to zero out the item then realise that the
  632  * item still owns it.
  633  * Retaddr is different. There are no references on that. It's just a number.
  634  * The debug versions must be either all used everywhere or not at all.
  635  */
  636 
  637 #define _NGI_M(i) ((i)->body.da_m)
  638 #define _NGI_MSG(i) ((i)->body.msg.msg_msg)
  639 #define _NGI_RETADDR(i) ((i)->body.msg.msg_retaddr)
  640 #define _NGI_FN(i) ((i)->body.fn.fn_fn)
  641 #define _NGI_ARG1(i) ((i)->body.fn.fn_arg1)
  642 #define _NGI_ARG2(i) ((i)->body.fn.fn_arg2)
  643 #define _NGI_NODE(i) ((i)->el_dest)
  644 #define _NGI_HOOK(i) ((i)->el_hook)
  645 #define _NGI_SET_HOOK(i,h) do { _NGI_HOOK(i) = h; h = NULL;} while (0)
  646 #define _NGI_CLR_HOOK(i)   do {                                         \
  647                 hook_p _hook = _NGI_HOOK(i);                            \
  648                 if (_hook) {                                            \
  649                         _NG_HOOK_UNREF(_hook);                          \
  650                         _NGI_HOOK(i) = NULL;                            \
  651                 }                                                       \
  652         } while (0)
  653 #define _NGI_SET_NODE(i,n) do { _NGI_NODE(i) = n; n = NULL;} while (0)
  654 #define _NGI_CLR_NODE(i)   do {                                         \
  655                 node_p _node = _NGI_NODE(i);                            \
  656                 if (_node) {                                            \
  657                         _NG_NODE_UNREF(_node);                          \
  658                         _NGI_NODE(i) = NULL;                            \
  659                 }                                                       \
  660         } while (0)
  661 
  662 #ifdef NETGRAPH_DEBUG /*----------------------------------------------*/
  663 void                            dumpitem(item_p item, char *file, int line);
  664 static __inline void            _ngi_check(item_p item, char *file, int line) ;
  665 static __inline struct mbuf **  _ngi_m(item_p item, char *file, int line) ;
  666 static __inline ng_ID_t *       _ngi_retaddr(item_p item, char *file, int line);
  667 static __inline struct ng_mesg ** _ngi_msg(item_p item, char *file, int line) ;
  668 static __inline ng_item_fn **   _ngi_fn(item_p item, char *file, int line) ;
  669 static __inline void **         _ngi_arg1(item_p item, char *file, int line) ;
  670 static __inline int *           _ngi_arg2(item_p item, char *file, int line) ;
  671 static __inline node_p          _ngi_node(item_p item, char *file, int line);
  672 static __inline hook_p          _ngi_hook(item_p item, char *file, int line);
  673 
  674 static __inline void
  675 _ngi_check(item_p item, char *file, int line)
  676 {
  677         (item)->lastline = line;
  678         (item)->lastfile = file;
  679 }
  680 
  681 static __inline struct mbuf **
  682 _ngi_m(item_p item, char *file, int line)
  683 {
  684         _ngi_check(item, file, line);
  685         return (&_NGI_M(item));
  686 }
  687 
  688 static __inline struct ng_mesg **
  689 _ngi_msg(item_p item, char *file, int line)
  690 {
  691         _ngi_check(item, file, line);
  692         return (&_NGI_MSG(item));
  693 }
  694 
  695 static __inline ng_ID_t *
  696 _ngi_retaddr(item_p item, char *file, int line)
  697 {
  698         _ngi_check(item, file, line);
  699         return (&_NGI_RETADDR(item));
  700 }
  701 
  702 static __inline ng_item_fn **
  703 _ngi_fn(item_p item, char *file, int line)
  704 {
  705         _ngi_check(item, file, line);
  706         return (&_NGI_FN(item));
  707 }
  708 
  709 static __inline void **
  710 _ngi_arg1(item_p item, char *file, int line)
  711 {
  712         _ngi_check(item, file, line);
  713         return (&_NGI_ARG1(item));
  714 }
  715 
  716 static __inline int *
  717 _ngi_arg2(item_p item, char *file, int line)
  718 {
  719         _ngi_check(item, file, line);
  720         return (&_NGI_ARG2(item));
  721 }
  722 
  723 static __inline node_p
  724 _ngi_node(item_p item, char *file, int line)
  725 {
  726         _ngi_check(item, file, line);
  727         return (_NGI_NODE(item));
  728 }
  729 
  730 static __inline hook_p
  731 _ngi_hook(item_p item, char *file, int line)
  732 {
  733         _ngi_check(item, file, line);
  734         return (_NGI_HOOK(item));
  735 }
  736 
  737 #define NGI_M(i)        (*_ngi_m(i, _NN_))
  738 #define NGI_MSG(i)      (*_ngi_msg(i, _NN_))
  739 #define NGI_RETADDR(i)  (*_ngi_retaddr(i, _NN_))
  740 #define NGI_FN(i)       (*_ngi_fn(i, _NN_))
  741 #define NGI_ARG1(i)     (*_ngi_arg1(i, _NN_))
  742 #define NGI_ARG2(i)     (*_ngi_arg2(i, _NN_))
  743 #define NGI_HOOK(i)     _ngi_hook(i, _NN_)
  744 #define NGI_NODE(i)     _ngi_node(i, _NN_)
  745 #define NGI_SET_HOOK(i,h)                                               \
  746         do { _ngi_check(i, _NN_); _NGI_SET_HOOK(i, h); } while (0)
  747 #define NGI_CLR_HOOK(i)                                                 \
  748         do { _ngi_check(i, _NN_); _NGI_CLR_HOOK(i); } while (0)
  749 #define NGI_SET_NODE(i,n)                                               \
  750         do { _ngi_check(i, _NN_); _NGI_SET_NODE(i, n); } while (0)
  751 #define NGI_CLR_NODE(i)                                                 \
  752         do { _ngi_check(i, _NN_); _NGI_CLR_NODE(i); } while (0)
  753 
  754 #define NG_FREE_ITEM(item)                                              \
  755         do {                                                            \
  756                 _ngi_check(item, _NN_);                                 \
  757                 ng_free_item((item));                                   \
  758         } while (0)
  759 
  760 #define SAVE_LINE(item)                                                 \
  761         do {                                                            \
  762                 (item)->lastline = __LINE__;                            \
  763                 (item)->lastfile = __FILE__;                            \
  764         } while (0)
  765 
  766 #else   /* NETGRAPH_DEBUG */ /*----------------------------------------------*/
  767 
  768 #define NGI_M(i)        _NGI_M(i)
  769 #define NGI_MSG(i)      _NGI_MSG(i)
  770 #define NGI_RETADDR(i)  _NGI_RETADDR(i)
  771 #define NGI_FN(i)       _NGI_FN(i)
  772 #define NGI_ARG1(i)     _NGI_ARG1(i)
  773 #define NGI_ARG2(i)     _NGI_ARG2(i)
  774 #define NGI_NODE(i)     _NGI_NODE(i)
  775 #define NGI_HOOK(i)     _NGI_HOOK(i)
  776 #define NGI_SET_HOOK(i,h) _NGI_SET_HOOK(i,h)
  777 #define NGI_CLR_HOOK(i)   _NGI_CLR_HOOK(i)
  778 #define NGI_SET_NODE(i,n) _NGI_SET_NODE(i,n)
  779 #define NGI_CLR_NODE(i)   _NGI_CLR_NODE(i)
  780 
  781 #define NG_FREE_ITEM(item)      ng_free_item((item))
  782 #define SAVE_LINE(item)         do {} while (0)
  783 
  784 #endif  /* NETGRAPH_DEBUG */ /*----------------------------------------------*/
  785 
  786 #define NGI_GET_M(i,m)                                                  \
  787         do {                                                            \
  788                 (m) = NGI_M(i);                                         \
  789                 _NGI_M(i) = NULL;                                       \
  790         } while (0)
  791 
  792 #define NGI_GET_MSG(i,m)                                                \
  793         do {                                                            \
  794                 (m) = NGI_MSG(i);                                       \
  795                 _NGI_MSG(i) = NULL;                                     \
  796         } while (0)
  797 
  798 #define NGI_GET_NODE(i,n)       /* YOU NOW HAVE THE REFERENCE */        \
  799         do {                                                            \
  800                 (n) = NGI_NODE(i);                                      \
  801                 _NGI_NODE(i) = NULL;                                    \
  802         } while (0)
  803 
  804 #define NGI_GET_HOOK(i,h)                                               \
  805         do {                                                            \
  806                 (h) = NGI_HOOK(i);                                      \
  807                 _NGI_HOOK(i) = NULL;                                    \
  808         } while (0)
  809 
  810 #define NGI_SET_WRITER(i)       ((i)->el_flags &= ~NGQF_QMODE)
  811 #define NGI_SET_READER(i)       ((i)->el_flags |= NGQF_QREADER)
  812 
  813 #define NGI_QUEUED_READER(i)    ((i)->el_flags & NGQF_QREADER)
  814 #define NGI_QUEUED_WRITER(i)    (((i)->el_flags & NGQF_QMODE) == NGQF_QWRITER)
  815         
  816 /**********************************************************************
  817 * Data macros.  Send, manipulate and free.
  818 **********************************************************************/
  819 /*
  820  * Assuming the data is already ok, just set the new address and send
  821  */
  822 #define NG_FWD_ITEM_HOOK_FLAGS(error, item, hook, flags)                \
  823         do {                                                            \
  824                 (error) =                                               \
  825                     ng_address_hook(NULL, (item), (hook), NG_NOFLAGS);  \
  826                 if (error == 0) {                                       \
  827                         SAVE_LINE(item);                                \
  828                         (error) = ng_snd_item((item), (flags));         \
  829                 }                                                       \
  830                 (item) = NULL;                                          \
  831         } while (0)
  832 #define NG_FWD_ITEM_HOOK(error, item, hook)     \
  833                 NG_FWD_ITEM_HOOK_FLAGS(error, item, hook, NG_NOFLAGS)
  834 
  835 /*
  836  * Forward a data packet. Mbuf pointer is updated to new value. We
  837  * presume you dealt with the old one when you update it to the new one
  838  * (or it maybe the old one). We got a packet and possibly had to modify
  839  * the mbuf. You should probably use NGI_GET_M() if you are going to use
  840  * this too.
  841  */
  842 #define NG_FWD_NEW_DATA_FLAGS(error, item, hook, m, flags)              \
  843         do {                                                            \
  844                 NGI_M(item) = (m);                                      \
  845                 (m) = NULL;                                             \
  846                 NG_FWD_ITEM_HOOK_FLAGS(error, item, hook, flags);       \
  847         } while (0)
  848 #define NG_FWD_NEW_DATA(error, item, hook, m)   \
  849                 NG_FWD_NEW_DATA_FLAGS(error, item, hook, m, NG_NOFLAGS)
  850 
  851 /* Send a previously unpackaged mbuf. XXX: This should be called
  852  * NG_SEND_DATA in future, but this name is kept for compatibility
  853  * reasons.
  854  */
  855 #define NG_SEND_DATA_FLAGS(error, hook, m, flags)                       \
  856         do {                                                            \
  857                 item_p _item;                                           \
  858                 if ((_item = ng_package_data((m), flags))) {            \
  859                         NG_FWD_ITEM_HOOK_FLAGS(error, _item, hook, flags);\
  860                 } else {                                                \
  861                         (error) = ENOMEM;                               \
  862                 }                                                       \
  863                 (m) = NULL;                                             \
  864         } while (0)
  865 
  866 #define NG_SEND_DATA_ONLY(error, hook, m)       \
  867                 NG_SEND_DATA_FLAGS(error, hook, m, NG_NOFLAGS)
  868 /* NG_SEND_DATA() compat for meta-data times */
  869 #define NG_SEND_DATA(error, hook, m, x) \
  870                 NG_SEND_DATA_FLAGS(error, hook, m, NG_NOFLAGS)
  871 
  872 #define NG_FREE_MSG(msg)                                                \
  873         do {                                                            \
  874                 if ((msg)) {                                            \
  875                         FREE((msg), M_NETGRAPH_MSG);                    \
  876                         (msg) = NULL;                                   \
  877                 }                                                       \
  878         } while (0)
  879 
  880 #define NG_FREE_M(m)                                                    \
  881         do {                                                            \
  882                 if ((m)) {                                              \
  883                         m_freem((m));                                   \
  884                         (m) = NULL;                                     \
  885                 }                                                       \
  886         } while (0)
  887 
  888 /*****************************************
  889 * Message macros
  890 *****************************************/
  891 
  892 #define NG_SEND_MSG_HOOK(error, here, msg, hook, retaddr)               \
  893         do {                                                            \
  894                 item_p _item;                                           \
  895                 if ((_item = ng_package_msg(msg, NG_NOFLAGS)) == NULL) {\
  896                         (msg) = NULL;                                   \
  897                         (error) = ENOMEM;                               \
  898                         break;                                          \
  899                 }                                                       \
  900                 if (((error) = ng_address_hook((here), (_item),         \
  901                                         (hook), (retaddr))) == 0) {     \
  902                         SAVE_LINE(_item);                               \
  903                         (error) = ng_snd_item((_item), 0);              \
  904                 }                                                       \
  905                 (msg) = NULL;                                           \
  906         } while (0)
  907 
  908 #define NG_SEND_MSG_PATH(error, here, msg, path, retaddr)               \
  909         do {                                                            \
  910                 item_p _item;                                           \
  911                 if ((_item = ng_package_msg(msg, NG_NOFLAGS)) == NULL) {\
  912                         (msg) = NULL;                                   \
  913                         (error) = ENOMEM;                               \
  914                         break;                                          \
  915                 }                                                       \
  916                 if (((error) = ng_address_path((here), (_item),         \
  917                                         (path), (retaddr))) == 0) {     \
  918                         SAVE_LINE(_item);                               \
  919                         (error) = ng_snd_item((_item), 0);              \
  920                 }                                                       \
  921                 (msg) = NULL;                                           \
  922         } while (0)
  923 
  924 #define NG_SEND_MSG_ID(error, here, msg, ID, retaddr)                   \
  925         do {                                                            \
  926                 item_p _item;                                           \
  927                 if ((_item = ng_package_msg(msg, NG_NOFLAGS)) == NULL) {\
  928                         (msg) = NULL;                                   \
  929                         (error) = ENOMEM;                               \
  930                         break;                                          \
  931                 }                                                       \
  932                 if (((error) = ng_address_ID((here), (_item),           \
  933                                         (ID), (retaddr))) == 0) {       \
  934                         SAVE_LINE(_item);                               \
  935                         (error) = ng_snd_item((_item), 0);              \
  936                 }                                                       \
  937                 (msg) = NULL;                                           \
  938         } while (0)
  939 
  940 /*
  941  * Redirect the message to the next hop using the given hook.
  942  * ng_retarget_msg() frees the item if there is an error
  943  * and returns an error code.  It returns 0 on success.
  944  */
  945 #define NG_FWD_MSG_HOOK(error, here, item, hook, retaddr)               \
  946         do {                                                            \
  947                 if (((error) = ng_address_hook((here), (item),          \
  948                                         (hook), (retaddr))) == 0) {     \
  949                         SAVE_LINE(item);                                \
  950                         (error) = ng_snd_item((item), 0);               \
  951                 }                                                       \
  952                 (item) = NULL;                                          \
  953         } while (0)
  954 
  955 /*
  956  * Send a queue item back to it's originator with a response message.
  957  * Assume original message was removed and freed separatly.
  958  */
  959 #define NG_RESPOND_MSG(error, here, item, resp)                         \
  960         do {                                                            \
  961                 if (resp) {                                             \
  962                         ng_ID_t _dest = NGI_RETADDR(item);              \
  963                         NGI_RETADDR(item) = 0;                          \
  964                         NGI_MSG(item) = resp;                           \
  965                         if ((ng_address_ID((here), (item),              \
  966                                         _dest, 0)) == 0) {              \
  967                                 SAVE_LINE(item);                        \
  968                                 (error) = ng_snd_item((item), NG_QUEUE);\
  969                         } else {                                        \
  970                                 NG_FREE_ITEM(item);                     \
  971                                 (error) = EINVAL;                       \
  972                         }                                               \
  973                 } else {                                                \
  974                         NG_FREE_ITEM(item);                             \
  975                 }                                                       \
  976                 (item) = NULL;                                          \
  977         } while (0)
  978 
  979 
  980 /***********************************************************************
  981  ******** Structures Definitions and Macros for defining a node  *******
  982  ***********************************************************************
  983  *
  984  * Here we define the structures needed to actually define a new node
  985  * type.
  986  */
  987 
  988 /*
  989  * Command list -- each node type specifies the command that it knows
  990  * how to convert between ASCII and binary using an array of these.
  991  * The last element in the array must be a terminator with cookie=0.
  992  */
  993 
  994 struct ng_cmdlist {
  995         u_int32_t                       cookie;         /* command typecookie */
  996         int                             cmd;            /* command number */
  997         const char                      *name;          /* command name */
  998         const struct ng_parse_type      *mesgType;      /* args if !NGF_RESP */
  999         const struct ng_parse_type      *respType;      /* args if NGF_RESP */
 1000 };
 1001 
 1002 /*
 1003  * Structure of a node type
 1004  * If data is sent to the "rcvdata()" entrypoint then the system
 1005  * may decide to defer it until later by queing it with the normal netgraph
 1006  * input queuing system.  This is decidde by the HK_QUEUE flag being set in
 1007  * the flags word of the peer (receiving) hook. The dequeuing mechanism will
 1008  * ensure it is not requeued again.
 1009  * Note the input queueing system is to allow modules
 1010  * to 'release the stack' or to pass data across spl layers.
 1011  * The data will be redelivered as soon as the NETISR code runs
 1012  * which may be almost immediatly.  A node may also do it's own queueing
 1013  * for other reasons (e.g. device output queuing).
 1014  */
 1015 struct ng_type {
 1016 
 1017         u_int32_t       version;        /* must equal NG_API_VERSION */
 1018         const char      *name;          /* Unique type name */
 1019         modeventhand_t  mod_event;      /* Module event handler (optional) */
 1020         ng_constructor_t *constructor;  /* Node constructor */
 1021         ng_rcvmsg_t     *rcvmsg;        /* control messages come here */
 1022         ng_close_t      *close;         /* warn about forthcoming shutdown */
 1023         ng_shutdown_t   *shutdown;      /* reset, and free resources */
 1024         ng_newhook_t    *newhook;       /* first notification of new hook */
 1025         ng_findhook_t   *findhook;      /* only if you have lots of hooks */
 1026         ng_connect_t    *connect;       /* final notification of new hook */
 1027         ng_rcvdata_t    *rcvdata;       /* data comes here */
 1028         ng_disconnect_t *disconnect;    /* notify on disconnect */
 1029 
 1030         const struct    ng_cmdlist *cmdlist;    /* commands we can convert */
 1031 
 1032         /* R/W data private to the base netgraph code DON'T TOUCH! */
 1033         LIST_ENTRY(ng_type) types;              /* linked list of all types */
 1034         int                 refs;               /* number of instances */
 1035 };
 1036 
 1037 /*
 1038  * Use the NETGRAPH_INIT() macro to link a node type into the
 1039  * netgraph system. This works for types compiled into the kernel
 1040  * as well as KLD modules. The first argument should be the type
 1041  * name (eg, echo) and the second a pointer to the type struct.
 1042  *
 1043  * If a different link time is desired, e.g., a device driver that
 1044  * needs to install its netgraph type before probing, use the
 1045  * NETGRAPH_INIT_ORDERED() macro instead.  Device drivers probably
 1046  * want to use SI_SUB_DRIVERS/SI_ORDER_FIRST.
 1047  */
 1048 
 1049 #define NETGRAPH_INIT_ORDERED(typename, typestructp, sub, order)        \
 1050 static moduledata_t ng_##typename##_mod = {                             \
 1051         "ng_" #typename,                                                \
 1052         ng_mod_event,                                                   \
 1053         (typestructp)                                                   \
 1054 };                                                                      \
 1055 DECLARE_MODULE(ng_##typename, ng_##typename##_mod, sub, order);         \
 1056 MODULE_DEPEND(ng_##typename, netgraph,  NG_ABI_VERSION,                 \
 1057                                         NG_ABI_VERSION,                 \
 1058                                         NG_ABI_VERSION)
 1059 
 1060 #define NETGRAPH_INIT(tn, tp)                                           \
 1061         NETGRAPH_INIT_ORDERED(tn, tp, SI_SUB_PSEUDO, SI_ORDER_ANY)
 1062 
 1063 /* Special malloc() type for netgraph structs and ctrl messages */
 1064 /* Only these two types should be visible to nodes */
 1065 MALLOC_DECLARE(M_NETGRAPH);
 1066 MALLOC_DECLARE(M_NETGRAPH_MSG);
 1067 
 1068 /* declare the base of the netgraph sysclt hierarchy */
 1069 /* but only if this file cares about sysctls */
 1070 #ifdef  SYSCTL_DECL
 1071 SYSCTL_DECL(_net_graph);
 1072 #endif
 1073 
 1074 /*
 1075  * Methods that the nodes can use.
 1076  * Many of these methods should usually NOT be used directly but via
 1077  * Macros above.
 1078  */
 1079 int     ng_address_ID(node_p here, item_p item, ng_ID_t ID, ng_ID_t retaddr);
 1080 int     ng_address_hook(node_p here, item_p item, hook_p hook, ng_ID_t retaddr);
 1081 int     ng_address_path(node_p here, item_p item, char *address, ng_ID_t raddr);
 1082 int     ng_bypass(hook_p hook1, hook_p hook2);
 1083 hook_p  ng_findhook(node_p node, const char *name);
 1084 struct  ng_type *ng_findtype(const char *type);
 1085 int     ng_make_node_common(struct ng_type *typep, node_p *nodep);
 1086 int     ng_name_node(node_p node, const char *name);
 1087 int     ng_newtype(struct ng_type *tp);
 1088 ng_ID_t ng_node2ID(node_p node);
 1089 item_p  ng_package_data(struct mbuf *m, int flags);
 1090 item_p  ng_package_msg(struct ng_mesg *msg, int flags);
 1091 item_p  ng_package_msg_self(node_p here, hook_p hook, struct ng_mesg *msg);
 1092 void    ng_replace_retaddr(node_p here, item_p item, ng_ID_t retaddr);
 1093 int     ng_rmhook_self(hook_p hook);    /* if a node wants to kill a hook */
 1094 int     ng_rmnode_self(node_p here);    /* if a node wants to suicide */
 1095 int     ng_rmtype(struct ng_type *tp);
 1096 int     ng_snd_item(item_p item, int queue);
 1097 int     ng_send_fn1(node_p node, hook_p hook, ng_item_fn *fn,
 1098         void *arg1, int arg2, int flags);
 1099 #define ng_send_fn(node, hook, fn, arg1, arg2) \
 1100         ng_send_fn1(node, hook, fn, arg1, arg2, NG_NOFLAGS)
 1101 int     ng_uncallout(struct callout *c, node_p node);
 1102 int     ng_callout(struct callout *c, node_p node, hook_p hook, int ticks,
 1103             ng_item_fn *fn, void * arg1, int arg2);
 1104 #define ng_callout_init(c)      callout_init(c, CALLOUT_MPSAFE)
 1105 
 1106 /* Flags for netgraph functions. */
 1107 #define NG_NOFLAGS      0x00000000      /* no special options */
 1108 #define NG_QUEUE        0x00000001      /* enqueue item, don't dispatch */
 1109 #define NG_WAITOK       0x00000002      /* use M_WAITOK, etc. */
 1110 #define NG_PROGRESS     0x00000004      /* return EINPROGRESS if queued */
 1111 
 1112 /*
 1113  * prototypes the user should DEFINITELY not use directly
 1114  */
 1115 void    ng_free_item(item_p item); /* Use NG_FREE_ITEM instead */
 1116 int     ng_mod_event(module_t mod, int what, void *arg);
 1117 
 1118 /*
 1119  * Tag definitions and constants
 1120  */
 1121 
 1122 #define NG_TAG_PRIO     1
 1123 
 1124 struct ng_tag_prio {
 1125         struct m_tag    tag;
 1126         char    priority;
 1127         char    discardability;
 1128 };
 1129 
 1130 #define NG_PRIO_CUTOFF          32
 1131 #define NG_PRIO_LINKSTATE       64
 1132 
 1133 /* Macros and declarations to keep compatibility with metadata, which
 1134  * is obsoleted now. To be deleted.
 1135  */
 1136 typedef void *meta_p;
 1137 #define _NGI_META(i)    NULL
 1138 #define NGI_META(i)     NULL
 1139 #define NG_FREE_META(meta)
 1140 #define NGI_GET_META(i,m)
 1141 #define ng_copy_meta(meta) NULL
 1142 
 1143 #endif /* _NETGRAPH_NETGRAPH_H_ */

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