The Design and Implementation of the FreeBSD Operating System, Second Edition
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FreeBSD/Linux Kernel Cross Reference
sys/netgraph7/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: src/sys/netgraph/netgraph.h,v 1.74 2008/06/24 18:49:49 gnn Exp $
   41  * $DragonFly: src/sys/netgraph7/netgraph.h,v 1.2 2008/06/26 23:05:35 dillon Exp $
   42  * $Whistle: netgraph.h,v 1.29 1999/11/01 07:56:13 julian Exp $
   43  */
   44 
   45 #ifndef _NETGRAPH_NETGRAPH_H_
   46 #define _NETGRAPH_NETGRAPH_H_
   47 
   48 #ifndef _KERNEL
   49 #error "This file should not be included in user level programs"
   50 #endif
   51 
   52 #include <sys/queue.h>
   53 #include <sys/malloc.h>
   54 #include <sys/module.h>
   55 #include <sys/mutex2.h>
   56 #include <netgraph7/ng_message.h>       /* NG_HOOKSIZ, NG_NODESIZ */
   57 #include "dragonfly.h"
   58 
   59 #ifdef HAVE_KERNEL_OPTION_HEADERS
   60 #include "opt_netgraph.h"
   61 #endif
   62 
   63 /* debugging options */
   64 #define NG_SEPARATE_MALLOC      /* make modules use their own malloc types */
   65 
   66 /*
   67  * This defines the in-kernel binary interface version.
   68  * It is possible to change this but leave the external message
   69  * API the same. Each type also has it's own cookies for versioning as well.
   70  * Change it for NETGRAPH_DEBUG version so we cannot mix debug and non debug
   71  * modules.
   72  */
   73 #define _NG_ABI_VERSION 12
   74 #ifdef  NETGRAPH_DEBUG /*----------------------------------------------*/
   75 #define NG_ABI_VERSION  (_NG_ABI_VERSION + 0x10000)
   76 #else   /* NETGRAPH_DEBUG */ /*----------------------------------------------*/
   77 #define NG_ABI_VERSION  _NG_ABI_VERSION
   78 #endif  /* NETGRAPH_DEBUG */ /*----------------------------------------------*/
   79 
   80 
   81 /*
   82  * Forward references for the basic structures so we can
   83  * define the typedefs and use them in the structures themselves.
   84  */
   85 struct ng_hook ;
   86 struct ng_node ;
   87 struct ng_item ;
   88 typedef struct ng_item *item_p;
   89 typedef struct ng_node *node_p;
   90 typedef struct ng_hook *hook_p;
   91 
   92 /* node method definitions */
   93 typedef int     ng_constructor_t(node_p node);
   94 typedef int     ng_close_t(node_p node);
   95 typedef int     ng_shutdown_t(node_p node);
   96 typedef int     ng_newhook_t(node_p node, hook_p hook, const char *name);
   97 typedef hook_p  ng_findhook_t(node_p node, const char *name);
   98 typedef int     ng_connect_t(hook_p hook);
   99 typedef int     ng_rcvmsg_t(node_p node, item_p item, hook_p lasthook);
  100 typedef int     ng_rcvdata_t(hook_p hook, item_p item);
  101 typedef int     ng_disconnect_t(hook_p hook);
  102 typedef int     ng_rcvitem (node_p node, hook_p hook, item_p item);
  103 
  104 /***********************************************************************
  105  ***************** Hook Structure and Methods **************************
  106  ***********************************************************************
  107  *
  108  * Structure of a hook
  109  */
  110 struct ng_hook {
  111         char    hk_name[NG_HOOKSIZ];    /* what this node knows this link as */
  112         void   *hk_private;             /* node dependant ID for this hook */
  113         int     hk_flags;               /* info about this hook/link */
  114         int     hk_type;                /* tbd: hook data link type */
  115         struct  ng_hook *hk_peer;       /* the other end of this link */
  116         struct  ng_node *hk_node;       /* The node this hook is attached to */
  117         LIST_ENTRY(ng_hook) hk_hooks;   /* linked list of all hooks on node */
  118         ng_rcvmsg_t     *hk_rcvmsg;     /* control messages come here */
  119         ng_rcvdata_t    *hk_rcvdata;    /* data comes here */
  120         int     hk_refs;                /* dont actually free this till 0 */
  121 #ifdef  NETGRAPH_DEBUG /*----------------------------------------------*/
  122 #define HK_MAGIC 0x78573011
  123         int     hk_magic;
  124         char    *lastfile;
  125         int     lastline;
  126         SLIST_ENTRY(ng_hook)      hk_all;               /* all existing items */
  127 #endif  /* NETGRAPH_DEBUG */ /*----------------------------------------------*/
  128 };
  129 /* Flags for a hook */
  130 #define HK_INVALID              0x0001  /* don't trust it! */
  131 #define HK_QUEUE                0x0002  /* queue for later delivery */
  132 #define HK_FORCE_WRITER         0x0004  /* Incoming data queued as a writer */
  133 #define HK_DEAD                 0x0008  /* This is the dead hook.. don't free */
  134 #define HK_HI_STACK             0x0010  /* Hook has hi stack usage */
  135 
  136 /*
  137  * Public Methods for hook
  138  * If you can't do it with these you probably shouldn;t be doing it.
  139  */
  140 void ng_unref_hook(hook_p hook); /* don't move this */
  141 #define _NG_HOOK_REF(hook)      atomic_add_int(&(hook)->hk_refs, 1)
  142 #define _NG_HOOK_NAME(hook)     ((hook)->hk_name)
  143 #define _NG_HOOK_UNREF(hook)    ng_unref_hook(hook)
  144 #define _NG_HOOK_SET_PRIVATE(hook, val) do {(hook)->hk_private = val;} while (0)
  145 #define _NG_HOOK_SET_RCVMSG(hook, val)  do {(hook)->hk_rcvmsg = val;} while (0)
  146 #define _NG_HOOK_SET_RCVDATA(hook, val) do {(hook)->hk_rcvdata = val;} while (0)
  147 #define _NG_HOOK_PRIVATE(hook)  ((hook)->hk_private)
  148 #define _NG_HOOK_NOT_VALID(hook)        ((hook)->hk_flags & HK_INVALID)
  149 #define _NG_HOOK_IS_VALID(hook) (!((hook)->hk_flags & HK_INVALID))
  150 #define _NG_HOOK_NODE(hook)     ((hook)->hk_node) /* only rvalue! */
  151 #define _NG_HOOK_PEER(hook)     ((hook)->hk_peer) /* only rvalue! */
  152 #define _NG_HOOK_FORCE_WRITER(hook)                             \
  153                 do { hook->hk_flags |= HK_FORCE_WRITER; } while (0)
  154 #define _NG_HOOK_FORCE_QUEUE(hook) do { hook->hk_flags |= HK_QUEUE; } while (0)
  155 #define _NG_HOOK_HI_STACK(hook) do { hook->hk_flags |= HK_HI_STACK; } while (0)
  156 
  157 /* Some shortcuts */
  158 #define NG_PEER_NODE(hook)      NG_HOOK_NODE(NG_HOOK_PEER(hook))
  159 #define NG_PEER_HOOK_NAME(hook) NG_HOOK_NAME(NG_HOOK_PEER(hook))
  160 #define NG_PEER_NODE_NAME(hook) NG_NODE_NAME(NG_PEER_NODE(hook))
  161 
  162 #ifdef  NETGRAPH_DEBUG /*----------------------------------------------*/
  163 #define _NN_ __FILE__,__LINE__
  164 void    dumphook (hook_p hook, char *file, int line);
  165 static __inline void    _chkhook(hook_p hook, char *file, int line);
  166 static __inline void    _ng_hook_ref(hook_p hook, char * file, int line);
  167 static __inline char *  _ng_hook_name(hook_p hook, char * file, int line);
  168 static __inline void    _ng_hook_unref(hook_p hook, char * file, int line);
  169 static __inline void    _ng_hook_set_private(hook_p hook,
  170                                 void * val, char * file, int line);
  171 static __inline void    _ng_hook_set_rcvmsg(hook_p hook,
  172                                 ng_rcvmsg_t *val, char * file, int line);
  173 static __inline void    _ng_hook_set_rcvdata(hook_p hook,
  174                                 ng_rcvdata_t *val, char * file, int line);
  175 static __inline void *  _ng_hook_private(hook_p hook, char * file, int line);
  176 static __inline int     _ng_hook_not_valid(hook_p hook, char * file, int line);
  177 static __inline int     _ng_hook_is_valid(hook_p hook, char * file, int line);
  178 static __inline node_p  _ng_hook_node(hook_p hook, char * file, int line);
  179 static __inline hook_p  _ng_hook_peer(hook_p hook, char * file, int line);
  180 static __inline void    _ng_hook_force_writer(hook_p hook, char * file,
  181                                         int line);
  182 static __inline void    _ng_hook_force_queue(hook_p hook, char * file, int line);
  183 
  184 static __inline void
  185 _chkhook(hook_p hook, char *file, int line)
  186 {
  187         if (hook->hk_magic != HK_MAGIC) {
  188                 printf("Accessing freed hook ");
  189                 dumphook(hook, file, line);
  190         }
  191         hook->lastline = line;
  192         hook->lastfile = file;
  193 }
  194 
  195 static __inline void
  196 _ng_hook_ref(hook_p hook, char * file, int line)
  197 {
  198         _chkhook(hook, file, line);
  199         _NG_HOOK_REF(hook);
  200 }
  201 
  202 static __inline char *
  203 _ng_hook_name(hook_p hook, char * file, int line)
  204 {
  205         _chkhook(hook, file, line);
  206         return (_NG_HOOK_NAME(hook));
  207 }
  208 
  209 static __inline void
  210 _ng_hook_unref(hook_p hook, char * file, int line)
  211 {
  212         _chkhook(hook, file, line);
  213         _NG_HOOK_UNREF(hook);
  214 }
  215 
  216 static __inline void
  217 _ng_hook_set_private(hook_p hook, void *val, char * file, int line)
  218 {
  219         _chkhook(hook, file, line);
  220         _NG_HOOK_SET_PRIVATE(hook, val);
  221 }
  222 
  223 static __inline void
  224 _ng_hook_set_rcvmsg(hook_p hook, ng_rcvmsg_t *val, char * file, int line)
  225 {
  226         _chkhook(hook, file, line);
  227         _NG_HOOK_SET_RCVMSG(hook, val);
  228 }
  229 
  230 static __inline void
  231 _ng_hook_set_rcvdata(hook_p hook, ng_rcvdata_t *val, char * file, int line)
  232 {
  233         _chkhook(hook, file, line);
  234         _NG_HOOK_SET_RCVDATA(hook, val);
  235 }
  236 
  237 static __inline void *
  238 _ng_hook_private(hook_p hook, char * file, int line)
  239 {
  240         _chkhook(hook, file, line);
  241         return (_NG_HOOK_PRIVATE(hook));
  242 }
  243 
  244 static __inline int
  245 _ng_hook_not_valid(hook_p hook, char * file, int line)
  246 {
  247         _chkhook(hook, file, line);
  248         return (_NG_HOOK_NOT_VALID(hook));
  249 }
  250 
  251 static __inline int
  252 _ng_hook_is_valid(hook_p hook, char * file, int line)
  253 {
  254         _chkhook(hook, file, line);
  255         return (_NG_HOOK_IS_VALID(hook));
  256 }
  257 
  258 static __inline node_p
  259 _ng_hook_node(hook_p hook, char * file, int line)
  260 {
  261         _chkhook(hook, file, line);
  262         return (_NG_HOOK_NODE(hook));
  263 }
  264 
  265 static __inline hook_p
  266 _ng_hook_peer(hook_p hook, char * file, int line)
  267 {
  268         _chkhook(hook, file, line);
  269         return (_NG_HOOK_PEER(hook));
  270 }
  271 
  272 static __inline void
  273 _ng_hook_force_writer(hook_p hook, char * file, int line)
  274 {
  275         _chkhook(hook, file, line);
  276         _NG_HOOK_FORCE_WRITER(hook);
  277 }
  278 
  279 static __inline void
  280 _ng_hook_force_queue(hook_p hook, char * file, int line)
  281 {
  282         _chkhook(hook, file, line);
  283         _NG_HOOK_FORCE_QUEUE(hook);
  284 }
  285 
  286 static __inline void
  287 _ng_hook_hi_stack(hook_p hook, char * file, int line)
  288 {
  289         _chkhook(hook, file, line);
  290         _NG_HOOK_HI_STACK(hook);
  291 }
  292 
  293 
  294 #define NG_HOOK_REF(hook)               _ng_hook_ref(hook, _NN_)
  295 #define NG_HOOK_NAME(hook)              _ng_hook_name(hook, _NN_)
  296 #define NG_HOOK_UNREF(hook)             _ng_hook_unref(hook, _NN_)
  297 #define NG_HOOK_SET_PRIVATE(hook, val)  _ng_hook_set_private(hook, val, _NN_)
  298 #define NG_HOOK_SET_RCVMSG(hook, val)   _ng_hook_set_rcvmsg(hook, val, _NN_)
  299 #define NG_HOOK_SET_RCVDATA(hook, val)  _ng_hook_set_rcvdata(hook, val, _NN_)
  300 #define NG_HOOK_PRIVATE(hook)           _ng_hook_private(hook, _NN_)
  301 #define NG_HOOK_NOT_VALID(hook)         _ng_hook_not_valid(hook, _NN_)
  302 #define NG_HOOK_IS_VALID(hook)          _ng_hook_is_valid(hook, _NN_)
  303 #define NG_HOOK_NODE(hook)              _ng_hook_node(hook, _NN_)
  304 #define NG_HOOK_PEER(hook)              _ng_hook_peer(hook, _NN_)
  305 #define NG_HOOK_FORCE_WRITER(hook)      _ng_hook_force_writer(hook, _NN_)
  306 #define NG_HOOK_FORCE_QUEUE(hook)       _ng_hook_force_queue(hook, _NN_)
  307 #define NG_HOOK_HI_STACK(hook)          _ng_hook_hi_stack(hook, _NN_)
  308 
  309 #else   /* NETGRAPH_DEBUG */ /*----------------------------------------------*/
  310 
  311 #define NG_HOOK_REF(hook)               _NG_HOOK_REF(hook)
  312 #define NG_HOOK_NAME(hook)              _NG_HOOK_NAME(hook)
  313 #define NG_HOOK_UNREF(hook)             _NG_HOOK_UNREF(hook)
  314 #define NG_HOOK_SET_PRIVATE(hook, val)  _NG_HOOK_SET_PRIVATE(hook, val)
  315 #define NG_HOOK_SET_RCVMSG(hook, val)   _NG_HOOK_SET_RCVMSG(hook, val)
  316 #define NG_HOOK_SET_RCVDATA(hook, val)  _NG_HOOK_SET_RCVDATA(hook, val)
  317 #define NG_HOOK_PRIVATE(hook)           _NG_HOOK_PRIVATE(hook)
  318 #define NG_HOOK_NOT_VALID(hook)         _NG_HOOK_NOT_VALID(hook)
  319 #define NG_HOOK_IS_VALID(hook)          _NG_HOOK_IS_VALID(hook)
  320 #define NG_HOOK_NODE(hook)              _NG_HOOK_NODE(hook)
  321 #define NG_HOOK_PEER(hook)              _NG_HOOK_PEER(hook)
  322 #define NG_HOOK_FORCE_WRITER(hook)      _NG_HOOK_FORCE_WRITER(hook)
  323 #define NG_HOOK_FORCE_QUEUE(hook)       _NG_HOOK_FORCE_QUEUE(hook)
  324 #define NG_HOOK_HI_STACK(hook)          _NG_HOOK_HI_STACK(hook)
  325 
  326 #endif  /* NETGRAPH_DEBUG */ /*----------------------------------------------*/
  327 
  328 /***********************************************************************
  329  ***************** Node Structure and Methods **************************
  330  ***********************************************************************
  331  * Structure of a node
  332  * including the eembedded queue structure.
  333  *
  334  * The structure for queueing Netgraph request items
  335  * embedded in the node structure
  336  */
  337 struct ng_queue {
  338         u_int           q_flags;        /* Current r/w/q lock flags */
  339         u_int           q_flags2;       /* Other queue flags */
  340         struct mtx      q_mtx;
  341         STAILQ_ENTRY(ng_node)   q_work; /* nodes with work to do */
  342         STAILQ_HEAD(, ng_item)  queue;  /* actually items queue */
  343 };
  344 
  345 struct ng_node {
  346         char    nd_name[NG_NODESIZ];    /* optional globally unique name */
  347         struct  ng_type *nd_type;       /* the installed 'type' */
  348         int     nd_flags;               /* see below for bit definitions */
  349         int     nd_numhooks;            /* number of hooks */
  350         void   *nd_private;             /* node type dependant node ID */
  351         ng_ID_t nd_ID;                  /* Unique per node */
  352         LIST_HEAD(hooks, ng_hook) nd_hooks;     /* linked list of node hooks */
  353         LIST_ENTRY(ng_node)       nd_nodes;     /* linked list of all nodes */
  354         LIST_ENTRY(ng_node)       nd_idnodes;   /* ID hash collision list */
  355         struct  ng_queue          nd_input_queue; /* input queue for locking */
  356         int     nd_refs;                /* # of references to this node */
  357 #ifdef  NETGRAPH_DEBUG /*----------------------------------------------*/
  358 #define ND_MAGIC 0x59264837
  359         int     nd_magic;
  360         char    *lastfile;
  361         int     lastline;
  362         SLIST_ENTRY(ng_node)      nd_all;       /* all existing nodes */
  363 #endif  /* NETGRAPH_DEBUG */ /*----------------------------------------------*/
  364 };
  365 
  366 /* Flags for a node */
  367 #define NGF_INVALID     0x00000001      /* free when refs go to 0 */
  368 #define NG_INVALID      NGF_INVALID     /* compat for old code */
  369 #define NGF_FORCE_WRITER        0x00000004      /* Never multithread this node */
  370 #define NG_FORCE_WRITER NGF_FORCE_WRITER /* compat for old code */
  371 #define NGF_CLOSING     0x00000008      /* ng_rmnode() at work */
  372 #define NG_CLOSING      NGF_CLOSING     /* compat for old code */
  373 #define NGF_REALLY_DIE  0x00000010      /* "persistent" node is unloading */
  374 #define NG_REALLY_DIE   NGF_REALLY_DIE  /* compat for old code */
  375 #define NGF_HI_STACK    0x00000020      /* node has hi stack usage */
  376 #define NGF_TYPE1       0x10000000      /* reserved for type specific storage */
  377 #define NGF_TYPE2       0x20000000      /* reserved for type specific storage */
  378 #define NGF_TYPE3       0x40000000      /* reserved for type specific storage */
  379 #define NGF_TYPE4       0x80000000      /* reserved for type specific storage */
  380 
  381 /*
  382  * Public methods for nodes.
  383  * If you can't do it with these you probably shouldn't be doing it.
  384  */
  385 int     ng_unref_node(node_p node); /* don't move this */
  386 #define _NG_NODE_NAME(node)     ((node)->nd_name + 0)
  387 #define _NG_NODE_HAS_NAME(node) ((node)->nd_name[0] + 0)
  388 #define _NG_NODE_ID(node)       ((node)->nd_ID + 0)
  389 #define _NG_NODE_REF(node)      atomic_add_int(&(node)->nd_refs, 1)
  390 #define _NG_NODE_UNREF(node)    ng_unref_node(node)
  391 #define _NG_NODE_SET_PRIVATE(node, val) do {(node)->nd_private = val;} while (0)
  392 #define _NG_NODE_PRIVATE(node)  ((node)->nd_private)
  393 #define _NG_NODE_IS_VALID(node) (!((node)->nd_flags & NGF_INVALID))
  394 #define _NG_NODE_NOT_VALID(node)        ((node)->nd_flags & NGF_INVALID)
  395 #define _NG_NODE_NUMHOOKS(node) ((node)->nd_numhooks + 0) /* rvalue */
  396 #define _NG_NODE_FORCE_WRITER(node)                                     \
  397         do{ node->nd_flags |= NGF_FORCE_WRITER; }while (0)
  398 #define _NG_NODE_HI_STACK(node)                                         \
  399         do{ node->nd_flags |= NGF_HI_STACK; }while (0)
  400 #define _NG_NODE_REALLY_DIE(node)                                       \
  401         do{ node->nd_flags |= (NGF_REALLY_DIE|NGF_INVALID); }while (0)
  402 #define _NG_NODE_REVIVE(node) \
  403         do { node->nd_flags &= ~NGF_INVALID; } while (0)
  404 /*
  405  * The hook iterator.
  406  * This macro will call a function of type ng_fn_eachhook for each
  407  * hook attached to the node. If the function returns 0, then the
  408  * iterator will stop and return a pointer to the hook that returned 0.
  409  */
  410 typedef int     ng_fn_eachhook(hook_p hook, void* arg);
  411 #define _NG_NODE_FOREACH_HOOK(node, fn, arg, rethook)                   \
  412         do {                                                            \
  413                 hook_p _hook;                                           \
  414                 (rethook) = NULL;                                       \
  415                 LIST_FOREACH(_hook, &((node)->nd_hooks), hk_hooks) {    \
  416                         if ((fn)(_hook, arg) == 0) {                    \
  417                                 (rethook) = _hook;                      \
  418                                 break;                                  \
  419                         }                                               \
  420                 }                                                       \
  421         } while (0)
  422 
  423 #ifdef  NETGRAPH_DEBUG /*----------------------------------------------*/
  424 void    dumpnode(node_p node, char *file, int line);
  425 static __inline void _chknode(node_p node, char *file, int line);
  426 static __inline char * _ng_node_name(node_p node, char *file, int line);
  427 static __inline int _ng_node_has_name(node_p node, char *file, int line);
  428 static __inline ng_ID_t _ng_node_id(node_p node, char *file, int line);
  429 static __inline void _ng_node_ref(node_p node, char *file, int line);
  430 static __inline int _ng_node_unref(node_p node, char *file, int line);
  431 static __inline void _ng_node_set_private(node_p node, void * val,
  432                                                         char *file, int line);
  433 static __inline void * _ng_node_private(node_p node, char *file, int line);
  434 static __inline int _ng_node_is_valid(node_p node, char *file, int line);
  435 static __inline int _ng_node_not_valid(node_p node, char *file, int line);
  436 static __inline int _ng_node_numhooks(node_p node, char *file, int line);
  437 static __inline void _ng_node_force_writer(node_p node, char *file, int line);
  438 static __inline hook_p _ng_node_foreach_hook(node_p node,
  439                         ng_fn_eachhook *fn, void *arg, char *file, int line);
  440 static __inline void _ng_node_revive(node_p node, char *file, int line);
  441 
  442 static __inline void
  443 _chknode(node_p node, char *file, int line)
  444 {
  445         if (node->nd_magic != ND_MAGIC) {
  446                 printf("Accessing freed node ");
  447                 dumpnode(node, file, line);
  448         }
  449         node->lastline = line;
  450         node->lastfile = file;
  451 }
  452 
  453 static __inline char *
  454 _ng_node_name(node_p node, char *file, int line)
  455 {
  456         _chknode(node, file, line);
  457         return(_NG_NODE_NAME(node));
  458 }
  459 
  460 static __inline int
  461 _ng_node_has_name(node_p node, char *file, int line)
  462 {
  463         _chknode(node, file, line);
  464         return(_NG_NODE_HAS_NAME(node));
  465 }
  466 
  467 static __inline ng_ID_t
  468 _ng_node_id(node_p node, char *file, int line)
  469 {
  470         _chknode(node, file, line);
  471         return(_NG_NODE_ID(node));
  472 }
  473 
  474 static __inline void
  475 _ng_node_ref(node_p node, char *file, int line)
  476 {
  477         _chknode(node, file, line);
  478         _NG_NODE_REF(node);
  479 }
  480 
  481 static __inline int
  482 _ng_node_unref(node_p node, char *file, int line)
  483 {
  484         _chknode(node, file, line);
  485         return (_NG_NODE_UNREF(node));
  486 }
  487 
  488 static __inline void
  489 _ng_node_set_private(node_p node, void * val, char *file, int line)
  490 {
  491         _chknode(node, file, line);
  492         _NG_NODE_SET_PRIVATE(node, val);
  493 }
  494 
  495 static __inline void *
  496 _ng_node_private(node_p node, char *file, int line)
  497 {
  498         _chknode(node, file, line);
  499         return (_NG_NODE_PRIVATE(node));
  500 }
  501 
  502 static __inline int
  503 _ng_node_is_valid(node_p node, char *file, int line)
  504 {
  505         _chknode(node, file, line);
  506         return(_NG_NODE_IS_VALID(node));
  507 }
  508 
  509 static __inline int
  510 _ng_node_not_valid(node_p node, char *file, int line)
  511 {
  512         _chknode(node, file, line);
  513         return(_NG_NODE_NOT_VALID(node));
  514 }
  515 
  516 static __inline int
  517 _ng_node_numhooks(node_p node, char *file, int line)
  518 {
  519         _chknode(node, file, line);
  520         return(_NG_NODE_NUMHOOKS(node));
  521 }
  522 
  523 static __inline void
  524 _ng_node_force_writer(node_p node, char *file, int line)
  525 {
  526         _chknode(node, file, line);
  527         _NG_NODE_FORCE_WRITER(node);
  528 }
  529 
  530 static __inline void
  531 _ng_node_hi_stack(node_p node, char *file, int line)
  532 {
  533         _chknode(node, file, line);
  534         _NG_NODE_HI_STACK(node);
  535 }
  536 
  537 static __inline void
  538 _ng_node_really_die(node_p node, char *file, int line)
  539 {
  540         _chknode(node, file, line);
  541         _NG_NODE_REALLY_DIE(node);
  542 }
  543 
  544 static __inline void
  545 _ng_node_revive(node_p node, char *file, int line)
  546 {
  547         _chknode(node, file, line);
  548         _NG_NODE_REVIVE(node);
  549 }
  550 
  551 static __inline hook_p
  552 _ng_node_foreach_hook(node_p node, ng_fn_eachhook *fn, void *arg,
  553                                                 char *file, int line)
  554 {
  555         hook_p hook;
  556         _chknode(node, file, line);
  557         _NG_NODE_FOREACH_HOOK(node, fn, arg, hook);
  558         return (hook);
  559 }
  560 
  561 #define NG_NODE_NAME(node)              _ng_node_name(node, _NN_)       
  562 #define NG_NODE_HAS_NAME(node)          _ng_node_has_name(node, _NN_)   
  563 #define NG_NODE_ID(node)                _ng_node_id(node, _NN_)
  564 #define NG_NODE_REF(node)               _ng_node_ref(node, _NN_)
  565 #define NG_NODE_UNREF(node)             _ng_node_unref(node, _NN_)
  566 #define NG_NODE_SET_PRIVATE(node, val)  _ng_node_set_private(node, val, _NN_)
  567 #define NG_NODE_PRIVATE(node)           _ng_node_private(node, _NN_)
  568 #define NG_NODE_IS_VALID(node)          _ng_node_is_valid(node, _NN_)
  569 #define NG_NODE_NOT_VALID(node)         _ng_node_not_valid(node, _NN_)
  570 #define NG_NODE_FORCE_WRITER(node)      _ng_node_force_writer(node, _NN_)
  571 #define NG_NODE_HI_STACK(node)          _ng_node_hi_stack(node, _NN_)
  572 #define NG_NODE_REALLY_DIE(node)        _ng_node_really_die(node, _NN_)
  573 #define NG_NODE_NUMHOOKS(node)          _ng_node_numhooks(node, _NN_)
  574 #define NG_NODE_REVIVE(node)            _ng_node_revive(node, _NN_)
  575 #define NG_NODE_FOREACH_HOOK(node, fn, arg, rethook)                          \
  576         do {                                                                  \
  577                 rethook = _ng_node_foreach_hook(node, fn, (void *)arg, _NN_); \
  578         } while (0)
  579 
  580 #else   /* NETGRAPH_DEBUG */ /*----------------------------------------------*/
  581 
  582 #define NG_NODE_NAME(node)              _NG_NODE_NAME(node)     
  583 #define NG_NODE_HAS_NAME(node)          _NG_NODE_HAS_NAME(node) 
  584 #define NG_NODE_ID(node)                _NG_NODE_ID(node)       
  585 #define NG_NODE_REF(node)               _NG_NODE_REF(node)      
  586 #define NG_NODE_UNREF(node)             _NG_NODE_UNREF(node)    
  587 #define NG_NODE_SET_PRIVATE(node, val)  _NG_NODE_SET_PRIVATE(node, val) 
  588 #define NG_NODE_PRIVATE(node)           _NG_NODE_PRIVATE(node)  
  589 #define NG_NODE_IS_VALID(node)          _NG_NODE_IS_VALID(node) 
  590 #define NG_NODE_NOT_VALID(node)         _NG_NODE_NOT_VALID(node)        
  591 #define NG_NODE_FORCE_WRITER(node)      _NG_NODE_FORCE_WRITER(node)
  592 #define NG_NODE_HI_STACK(node)          _NG_NODE_HI_STACK(node)
  593 #define NG_NODE_REALLY_DIE(node)        _NG_NODE_REALLY_DIE(node)
  594 #define NG_NODE_NUMHOOKS(node)          _NG_NODE_NUMHOOKS(node) 
  595 #define NG_NODE_REVIVE(node)            _NG_NODE_REVIVE(node)
  596 #define NG_NODE_FOREACH_HOOK(node, fn, arg, rethook)                    \
  597                 _NG_NODE_FOREACH_HOOK(node, fn, arg, rethook)
  598 #endif  /* NETGRAPH_DEBUG */ /*----------------------------------------------*/
  599 
  600 /***********************************************************************
  601  ************* Node Queue and Item Structures and Methods **************
  602  ***********************************************************************
  603  *
  604  */
  605 typedef void    ng_item_fn(node_p node, hook_p hook, void *arg1, int arg2);
  606 typedef int     ng_item_fn2(node_p node, struct ng_item *item, hook_p hook);
  607 typedef void    ng_apply_t(void *context, int error);
  608 struct ng_apply_info {
  609         ng_apply_t      *apply;
  610         void            *context;
  611         int             refs;
  612         int             error;
  613 };
  614 struct ng_item {
  615         u_long  el_flags;
  616         STAILQ_ENTRY(ng_item)   el_next;
  617         node_p  el_dest; /* The node it will be applied against (or NULL) */
  618         hook_p  el_hook; /* Entering hook. Optional in Control messages */
  619         union {
  620                 struct mbuf     *da_m;
  621                 struct {
  622                         struct ng_mesg  *msg_msg;
  623                         ng_ID_t         msg_retaddr;
  624                 } msg;
  625                 struct {
  626                         union {
  627                                 ng_item_fn      *fn_fn;
  628                                 ng_item_fn2     *fn_fn2;
  629                         } fn_fn;
  630                         void            *fn_arg1;
  631                         int             fn_arg2;
  632                 } fn;
  633         } body;
  634         /*
  635          * Optional callback called when item is being applied,
  636          * and its context.
  637          */
  638         struct ng_apply_info    *apply;
  639         u_int   depth;
  640 #ifdef  NETGRAPH_DEBUG /*----------------------------------------------*/
  641         char *lastfile;
  642         int  lastline;
  643         TAILQ_ENTRY(ng_item)      all;          /* all existing items */
  644 #endif  /* NETGRAPH_DEBUG */ /*----------------------------------------------*/
  645 };
  646 
  647 #define NGQF_TYPE       0x03            /* MASK of content definition */
  648 #define NGQF_MESG       0x00            /* the queue element is a message */
  649 #define NGQF_DATA       0x01            /* the queue element is data */
  650 #define NGQF_FN         0x02            /* the queue element is a function */
  651 #define NGQF_FN2        0x03            /* the queue element is a new function */
  652 
  653 #define NGQF_RW         0x04            /* MASK for wanted queue mode */
  654 #define NGQF_READER     0x04            /* wants to be a reader */
  655 #define NGQF_WRITER     0x00            /* wants to be a writer */
  656 
  657 #define NGQF_QMODE      0x08            /* MASK for how it was queued */
  658 #define NGQF_QREADER    0x08            /* was queued as a reader */
  659 #define NGQF_QWRITER    0x00            /* was queued as a writer */
  660 
  661 /*
  662  * Get the mbuf (etc) out of an item.
  663  * Sets the value in the item to NULL in case we need to call NG_FREE_ITEM()
  664  * with it, (to avoid freeing the things twice).
  665  * If you don't want to zero out the item then realise that the
  666  * item still owns it.
  667  * Retaddr is different. There are no references on that. It's just a number.
  668  * The debug versions must be either all used everywhere or not at all.
  669  */
  670 
  671 #define _NGI_M(i) ((i)->body.da_m)
  672 #define _NGI_MSG(i) ((i)->body.msg.msg_msg)
  673 #define _NGI_RETADDR(i) ((i)->body.msg.msg_retaddr)
  674 #define _NGI_FN(i) ((i)->body.fn.fn_fn.fn_fn)
  675 #define _NGI_FN2(i) ((i)->body.fn.fn_fn.fn_fn2)
  676 #define _NGI_ARG1(i) ((i)->body.fn.fn_arg1)
  677 #define _NGI_ARG2(i) ((i)->body.fn.fn_arg2)
  678 #define _NGI_NODE(i) ((i)->el_dest)
  679 #define _NGI_HOOK(i) ((i)->el_hook)
  680 #define _NGI_SET_HOOK(i,h) do { _NGI_HOOK(i) = h; h = NULL;} while (0)
  681 #define _NGI_CLR_HOOK(i)   do {                                         \
  682                 hook_p _hook = _NGI_HOOK(i);                            \
  683                 if (_hook) {                                            \
  684                         _NG_HOOK_UNREF(_hook);                          \
  685                         _NGI_HOOK(i) = NULL;                            \
  686                 }                                                       \
  687         } while (0)
  688 #define _NGI_SET_NODE(i,n) do { _NGI_NODE(i) = n; n = NULL;} while (0)
  689 #define _NGI_CLR_NODE(i)   do {                                         \
  690                 node_p _node = _NGI_NODE(i);                            \
  691                 if (_node) {                                            \
  692                         _NG_NODE_UNREF(_node);                          \
  693                         _NGI_NODE(i) = NULL;                            \
  694                 }                                                       \
  695         } while (0)
  696 
  697 #ifdef NETGRAPH_DEBUG /*----------------------------------------------*/
  698 void                            dumpitem(item_p item, char *file, int line);
  699 static __inline void            _ngi_check(item_p item, char *file, int line) ;
  700 static __inline struct mbuf **  _ngi_m(item_p item, char *file, int line) ;
  701 static __inline ng_ID_t *       _ngi_retaddr(item_p item, char *file, int line);
  702 static __inline struct ng_mesg ** _ngi_msg(item_p item, char *file, int line) ;
  703 static __inline ng_item_fn **   _ngi_fn(item_p item, char *file, int line) ;
  704 static __inline ng_item_fn2 **  _ngi_fn2(item_p item, char *file, int line) ;
  705 static __inline void **         _ngi_arg1(item_p item, char *file, int line) ;
  706 static __inline int *           _ngi_arg2(item_p item, char *file, int line) ;
  707 static __inline node_p          _ngi_node(item_p item, char *file, int line);
  708 static __inline hook_p          _ngi_hook(item_p item, char *file, int line);
  709 
  710 static __inline void
  711 _ngi_check(item_p item, char *file, int line)
  712 {
  713         (item)->lastline = line;
  714         (item)->lastfile = file;
  715 }
  716 
  717 static __inline struct mbuf **
  718 _ngi_m(item_p item, char *file, int line)
  719 {
  720         _ngi_check(item, file, line);
  721         return (&_NGI_M(item));
  722 }
  723 
  724 static __inline struct ng_mesg **
  725 _ngi_msg(item_p item, char *file, int line)
  726 {
  727         _ngi_check(item, file, line);
  728         return (&_NGI_MSG(item));
  729 }
  730 
  731 static __inline ng_ID_t *
  732 _ngi_retaddr(item_p item, char *file, int line)
  733 {
  734         _ngi_check(item, file, line);
  735         return (&_NGI_RETADDR(item));
  736 }
  737 
  738 static __inline ng_item_fn **
  739 _ngi_fn(item_p item, char *file, int line)
  740 {
  741         _ngi_check(item, file, line);
  742         return (&_NGI_FN(item));
  743 }
  744 
  745 static __inline ng_item_fn2 **
  746 _ngi_fn2(item_p item, char *file, int line)
  747 {
  748         _ngi_check(item, file, line);
  749         return (&_NGI_FN2(item));
  750 }
  751 
  752 static __inline void **
  753 _ngi_arg1(item_p item, char *file, int line)
  754 {
  755         _ngi_check(item, file, line);
  756         return (&_NGI_ARG1(item));
  757 }
  758 
  759 static __inline int *
  760 _ngi_arg2(item_p item, char *file, int line)
  761 {
  762         _ngi_check(item, file, line);
  763         return (&_NGI_ARG2(item));
  764 }
  765 
  766 static __inline node_p
  767 _ngi_node(item_p item, char *file, int line)
  768 {
  769         _ngi_check(item, file, line);
  770         return (_NGI_NODE(item));
  771 }
  772 
  773 static __inline hook_p
  774 _ngi_hook(item_p item, char *file, int line)
  775 {
  776         _ngi_check(item, file, line);
  777         return (_NGI_HOOK(item));
  778 }
  779 
  780 #define NGI_M(i)        (*_ngi_m(i, _NN_))
  781 #define NGI_MSG(i)      (*_ngi_msg(i, _NN_))
  782 #define NGI_RETADDR(i)  (*_ngi_retaddr(i, _NN_))
  783 #define NGI_FN(i)       (*_ngi_fn(i, _NN_))
  784 #define NGI_FN2(i)      (*_ngi_fn2(i, _NN_))
  785 #define NGI_ARG1(i)     (*_ngi_arg1(i, _NN_))
  786 #define NGI_ARG2(i)     (*_ngi_arg2(i, _NN_))
  787 #define NGI_HOOK(i)     _ngi_hook(i, _NN_)
  788 #define NGI_NODE(i)     _ngi_node(i, _NN_)
  789 #define NGI_SET_HOOK(i,h)                                               \
  790         do { _ngi_check(i, _NN_); _NGI_SET_HOOK(i, h); } while (0)
  791 #define NGI_CLR_HOOK(i)                                                 \
  792         do { _ngi_check(i, _NN_); _NGI_CLR_HOOK(i); } while (0)
  793 #define NGI_SET_NODE(i,n)                                               \
  794         do { _ngi_check(i, _NN_); _NGI_SET_NODE(i, n); } while (0)
  795 #define NGI_CLR_NODE(i)                                                 \
  796         do { _ngi_check(i, _NN_); _NGI_CLR_NODE(i); } while (0)
  797 
  798 #define NG_FREE_ITEM(item)                                              \
  799         do {                                                            \
  800                 _ngi_check(item, _NN_);                                 \
  801                 ng_free_item((item));                                   \
  802         } while (0)
  803 
  804 #define SAVE_LINE(item)                                                 \
  805         do {                                                            \
  806                 (item)->lastline = __LINE__;                            \
  807                 (item)->lastfile = __FILE__;                            \
  808         } while (0)
  809 
  810 #else   /* NETGRAPH_DEBUG */ /*----------------------------------------------*/
  811 
  812 #define NGI_M(i)        _NGI_M(i)
  813 #define NGI_MSG(i)      _NGI_MSG(i)
  814 #define NGI_RETADDR(i)  _NGI_RETADDR(i)
  815 #define NGI_FN(i)       _NGI_FN(i)
  816 #define NGI_FN2(i)      _NGI_FN2(i)
  817 #define NGI_ARG1(i)     _NGI_ARG1(i)
  818 #define NGI_ARG2(i)     _NGI_ARG2(i)
  819 #define NGI_NODE(i)     _NGI_NODE(i)
  820 #define NGI_HOOK(i)     _NGI_HOOK(i)
  821 #define NGI_SET_HOOK(i,h) _NGI_SET_HOOK(i,h)
  822 #define NGI_CLR_HOOK(i)   _NGI_CLR_HOOK(i)
  823 #define NGI_SET_NODE(i,n) _NGI_SET_NODE(i,n)
  824 #define NGI_CLR_NODE(i)   _NGI_CLR_NODE(i)
  825 
  826 #define NG_FREE_ITEM(item)      ng_free_item((item))
  827 #define SAVE_LINE(item)         do {} while (0)
  828 
  829 #endif  /* NETGRAPH_DEBUG */ /*----------------------------------------------*/
  830 
  831 #define NGI_GET_M(i,m)                                                  \
  832         do {                                                            \
  833                 (m) = NGI_M(i);                                         \
  834                 _NGI_M(i) = NULL;                                       \
  835         } while (0)
  836 
  837 #define NGI_GET_MSG(i,m)                                                \
  838         do {                                                            \
  839                 (m) = NGI_MSG(i);                                       \
  840                 _NGI_MSG(i) = NULL;                                     \
  841         } while (0)
  842 
  843 #define NGI_GET_NODE(i,n)       /* YOU NOW HAVE THE REFERENCE */        \
  844         do {                                                            \
  845                 (n) = NGI_NODE(i);                                      \
  846                 _NGI_NODE(i) = NULL;                                    \
  847         } while (0)
  848 
  849 #define NGI_GET_HOOK(i,h)                                               \
  850         do {                                                            \
  851                 (h) = NGI_HOOK(i);                                      \
  852                 _NGI_HOOK(i) = NULL;                                    \
  853         } while (0)
  854 
  855 #define NGI_SET_WRITER(i)       ((i)->el_flags &= ~NGQF_QMODE)
  856 #define NGI_SET_READER(i)       ((i)->el_flags |= NGQF_QREADER)
  857 
  858 #define NGI_QUEUED_READER(i)    ((i)->el_flags & NGQF_QREADER)
  859 #define NGI_QUEUED_WRITER(i)    (((i)->el_flags & NGQF_QMODE) == NGQF_QWRITER)
  860         
  861 /**********************************************************************
  862 * Data macros.  Send, manipulate and free.
  863 **********************************************************************/
  864 /*
  865  * Assuming the data is already ok, just set the new address and send
  866  */
  867 #define NG_FWD_ITEM_HOOK_FLAGS(error, item, hook, flags)                \
  868         do {                                                            \
  869                 (error) =                                               \
  870                     ng_address_hook(NULL, (item), (hook), NG_NOFLAGS);  \
  871                 if (error == 0) {                                       \
  872                         SAVE_LINE(item);                                \
  873                         (error) = ng_snd_item((item), (flags));         \
  874                 }                                                       \
  875                 (item) = NULL;                                          \
  876         } while (0)
  877 #define NG_FWD_ITEM_HOOK(error, item, hook)     \
  878                 NG_FWD_ITEM_HOOK_FLAGS(error, item, hook, NG_NOFLAGS)
  879 
  880 /*
  881  * Forward a data packet. Mbuf pointer is updated to new value. We
  882  * presume you dealt with the old one when you update it to the new one
  883  * (or it maybe the old one). We got a packet and possibly had to modify
  884  * the mbuf. You should probably use NGI_GET_M() if you are going to use
  885  * this too.
  886  */
  887 #define NG_FWD_NEW_DATA_FLAGS(error, item, hook, m, flags)              \
  888         do {                                                            \
  889                 NGI_M(item) = (m);                                      \
  890                 (m) = NULL;                                             \
  891                 NG_FWD_ITEM_HOOK_FLAGS(error, item, hook, flags);       \
  892         } while (0)
  893 #define NG_FWD_NEW_DATA(error, item, hook, m)   \
  894                 NG_FWD_NEW_DATA_FLAGS(error, item, hook, m, NG_NOFLAGS)
  895 
  896 /* Send a previously unpackaged mbuf. XXX: This should be called
  897  * NG_SEND_DATA in future, but this name is kept for compatibility
  898  * reasons.
  899  */
  900 #define NG_SEND_DATA_FLAGS(error, hook, m, flags)                       \
  901         do {                                                            \
  902                 item_p _item;                                           \
  903                 if ((_item = ng_package_data((m), flags))) {            \
  904                         NG_FWD_ITEM_HOOK_FLAGS(error, _item, hook, flags);\
  905                 } else {                                                \
  906                         (error) = ENOMEM;                               \
  907                 }                                                       \
  908                 (m) = NULL;                                             \
  909         } while (0)
  910 
  911 #define NG_SEND_DATA_ONLY(error, hook, m)       \
  912                 NG_SEND_DATA_FLAGS(error, hook, m, NG_NOFLAGS)
  913 /* NG_SEND_DATA() compat for meta-data times */
  914 #define NG_SEND_DATA(error, hook, m, x) \
  915                 NG_SEND_DATA_FLAGS(error, hook, m, NG_NOFLAGS)
  916 
  917 #define NG_FREE_MSG(msg)                                                \
  918         do {                                                            \
  919                 if ((msg)) {                                            \
  920                         kfree((msg), M_NETGRAPH_MSG);                   \
  921                         (msg) = NULL;                                   \
  922                 }                                                       \
  923         } while (0)
  924 
  925 #define NG_FREE_M(m)                                                    \
  926         do {                                                            \
  927                 if ((m)) {                                              \
  928                         m_freem((m));                                   \
  929                         (m) = NULL;                                     \
  930                 }                                                       \
  931         } while (0)
  932 
  933 /*****************************************
  934 * Message macros
  935 *****************************************/
  936 
  937 #define NG_SEND_MSG_HOOK(error, here, msg, hook, retaddr)               \
  938         do {                                                            \
  939                 item_p _item;                                           \
  940                 if ((_item = ng_package_msg(msg, NG_NOFLAGS)) == NULL) {\
  941                         (msg) = NULL;                                   \
  942                         (error) = ENOMEM;                               \
  943                         break;                                          \
  944                 }                                                       \
  945                 if (((error) = ng_address_hook((here), (_item),         \
  946                                         (hook), (retaddr))) == 0) {     \
  947                         SAVE_LINE(_item);                               \
  948                         (error) = ng_snd_item((_item), 0);              \
  949                 }                                                       \
  950                 (msg) = NULL;                                           \
  951         } while (0)
  952 
  953 #define NG_SEND_MSG_PATH(error, here, msg, path, retaddr)               \
  954         do {                                                            \
  955                 item_p _item;                                           \
  956                 if ((_item = ng_package_msg(msg, NG_NOFLAGS)) == NULL) {\
  957                         (msg) = NULL;                                   \
  958                         (error) = ENOMEM;                               \
  959                         break;                                          \
  960                 }                                                       \
  961                 if (((error) = ng_address_path((here), (_item),         \
  962                                         (path), (retaddr))) == 0) {     \
  963                         SAVE_LINE(_item);                               \
  964                         (error) = ng_snd_item((_item), 0);              \
  965                 }                                                       \
  966                 (msg) = NULL;                                           \
  967         } while (0)
  968 
  969 #define NG_SEND_MSG_ID(error, here, msg, ID, retaddr)                   \
  970         do {                                                            \
  971                 item_p _item;                                           \
  972                 if ((_item = ng_package_msg(msg, NG_NOFLAGS)) == NULL) {\
  973                         (msg) = NULL;                                   \
  974                         (error) = ENOMEM;                               \
  975                         break;                                          \
  976                 }                                                       \
  977                 if (((error) = ng_address_ID((here), (_item),           \
  978                                         (ID), (retaddr))) == 0) {       \
  979                         SAVE_LINE(_item);                               \
  980                         (error) = ng_snd_item((_item), 0);              \
  981                 }                                                       \
  982                 (msg) = NULL;                                           \
  983         } while (0)
  984 
  985 /*
  986  * Redirect the message to the next hop using the given hook.
  987  * ng_retarget_msg() frees the item if there is an error
  988  * and returns an error code.  It returns 0 on success.
  989  */
  990 #define NG_FWD_MSG_HOOK(error, here, item, hook, retaddr)               \
  991         do {                                                            \
  992                 if (((error) = ng_address_hook((here), (item),          \
  993                                         (hook), (retaddr))) == 0) {     \
  994                         SAVE_LINE(item);                                \
  995                         (error) = ng_snd_item((item), 0);               \
  996                 }                                                       \
  997                 (item) = NULL;                                          \
  998         } while (0)
  999 
 1000 /*
 1001  * Send a queue item back to it's originator with a response message.
 1002  * Assume original message was removed and freed separatly.
 1003  */
 1004 #define NG_RESPOND_MSG(error, here, item, resp)                         \
 1005         do {                                                            \
 1006                 if (resp) {                                             \
 1007                         ng_ID_t _dest = NGI_RETADDR(item);              \
 1008                         NGI_RETADDR(item) = 0;                          \
 1009                         NGI_MSG(item) = resp;                           \
 1010                         if ((error = ng_address_ID((here), (item),      \
 1011                                         _dest, 0)) == 0) {              \
 1012                                 SAVE_LINE(item);                        \
 1013                                 (error) = ng_snd_item((item), NG_QUEUE);\
 1014                         }                                               \
 1015                 } else                                                  \
 1016                         NG_FREE_ITEM(item);                             \
 1017                 (item) = NULL;                                          \
 1018         } while (0)
 1019 
 1020 
 1021 /***********************************************************************
 1022  ******** Structures Definitions and Macros for defining a node  *******
 1023  ***********************************************************************
 1024  *
 1025  * Here we define the structures needed to actually define a new node
 1026  * type.
 1027  */
 1028 
 1029 /*
 1030  * Command list -- each node type specifies the command that it knows
 1031  * how to convert between ASCII and binary using an array of these.
 1032  * The last element in the array must be a terminator with cookie=0.
 1033  */
 1034 
 1035 struct ng_cmdlist {
 1036         u_int32_t                       cookie;         /* command typecookie */
 1037         int                             cmd;            /* command number */
 1038         const char                      *name;          /* command name */
 1039         const struct ng_parse_type      *mesgType;      /* args if !NGF_RESP */
 1040         const struct ng_parse_type      *respType;      /* args if NGF_RESP */
 1041 };
 1042 
 1043 /*
 1044  * Structure of a node type
 1045  * If data is sent to the "rcvdata()" entrypoint then the system
 1046  * may decide to defer it until later by queing it with the normal netgraph
 1047  * input queuing system.  This is decidde by the HK_QUEUE flag being set in
 1048  * the flags word of the peer (receiving) hook. The dequeuing mechanism will
 1049  * ensure it is not requeued again.
 1050  * Note the input queueing system is to allow modules
 1051  * to 'release the stack' or to pass data across spl layers.
 1052  * The data will be redelivered as soon as the NETISR code runs
 1053  * which may be almost immediatly.  A node may also do it's own queueing
 1054  * for other reasons (e.g. device output queuing).
 1055  */
 1056 struct ng_type {
 1057 
 1058         u_int32_t       version;        /* must equal NG_API_VERSION */
 1059         const char      *name;          /* Unique type name */
 1060         modeventhand_t  mod_event;      /* Module event handler (optional) */
 1061         ng_constructor_t *constructor;  /* Node constructor */
 1062         ng_rcvmsg_t     *rcvmsg;        /* control messages come here */
 1063         ng_close_t      *close;         /* warn about forthcoming shutdown */
 1064         ng_shutdown_t   *shutdown;      /* reset, and free resources */
 1065         ng_newhook_t    *newhook;       /* first notification of new hook */
 1066         ng_findhook_t   *findhook;      /* only if you have lots of hooks */
 1067         ng_connect_t    *connect;       /* final notification of new hook */
 1068         ng_rcvdata_t    *rcvdata;       /* data comes here */
 1069         ng_disconnect_t *disconnect;    /* notify on disconnect */
 1070 
 1071         const struct    ng_cmdlist *cmdlist;    /* commands we can convert */
 1072 
 1073         /* R/W data private to the base netgraph code DON'T TOUCH! */
 1074         LIST_ENTRY(ng_type) types;              /* linked list of all types */
 1075         int                 refs;               /* number of instances */
 1076 };
 1077 
 1078 /*
 1079  * Use the NETGRAPH_INIT() macro to link a node type into the
 1080  * netgraph system. This works for types compiled into the kernel
 1081  * as well as KLD modules. The first argument should be the type
 1082  * name (eg, echo) and the second a pointer to the type struct.
 1083  *
 1084  * If a different link time is desired, e.g., a device driver that
 1085  * needs to install its netgraph type before probing, use the
 1086  * NETGRAPH_INIT_ORDERED() macro instead.  Device drivers probably
 1087  * want to use SI_SUB_DRIVERS/SI_ORDER_FIRST.
 1088  */
 1089 
 1090 #define NETGRAPH_INIT_ORDERED(typename, typestructp, sub, order)        \
 1091 static moduledata_t ng_##typename##_mod = {                             \
 1092         "ng_" #typename,                                                \
 1093         ng_mod_event,                                                   \
 1094         (typestructp)                                                   \
 1095 };                                                                      \
 1096 DECLARE_MODULE(ng_##typename, ng_##typename##_mod, sub, order);         \
 1097 MODULE_DEPEND(ng_##typename, netgraph,  NG_ABI_VERSION,                 \
 1098                                         NG_ABI_VERSION,                 \
 1099                                         NG_ABI_VERSION)
 1100 
 1101 #define NETGRAPH_INIT(tn, tp)                                           \
 1102         NETGRAPH_INIT_ORDERED(tn, tp, SI_SUB_PSEUDO, SI_ORDER_ANY)
 1103 
 1104 /* Special malloc() type for netgraph structs and ctrl messages */
 1105 /* Only these two types should be visible to nodes */
 1106 MALLOC_DECLARE(M_NETGRAPH);
 1107 MALLOC_DECLARE(M_NETGRAPH_MSG);
 1108 
 1109 /* declare the base of the netgraph sysclt hierarchy */
 1110 /* but only if this file cares about sysctls */
 1111 #ifdef  SYSCTL_DECL
 1112 SYSCTL_DECL(_net_graph);
 1113 #endif
 1114 
 1115 /*
 1116  * Methods that the nodes can use.
 1117  * Many of these methods should usually NOT be used directly but via
 1118  * Macros above.
 1119  */
 1120 int     ng_address_ID(node_p here, item_p item, ng_ID_t ID, ng_ID_t retaddr);
 1121 int     ng_address_hook(node_p here, item_p item, hook_p hook, ng_ID_t retaddr);
 1122 int     ng_address_path(node_p here, item_p item, char *address, ng_ID_t raddr);
 1123 int     ng_bypass(hook_p hook1, hook_p hook2);
 1124 hook_p  ng_findhook(node_p node, const char *name);
 1125 struct  ng_type *ng_findtype(const char *type);
 1126 int     ng_make_node_common(struct ng_type *typep, node_p *nodep);
 1127 int     ng_name_node(node_p node, const char *name);
 1128 int     ng_newtype(struct ng_type *tp);
 1129 ng_ID_t ng_node2ID(node_p node);
 1130 item_p  ng_package_data(struct mbuf *m, int flags);
 1131 item_p  ng_package_msg(struct ng_mesg *msg, int flags);
 1132 item_p  ng_package_msg_self(node_p here, hook_p hook, struct ng_mesg *msg);
 1133 void    ng_replace_retaddr(node_p here, item_p item, ng_ID_t retaddr);
 1134 int     ng_rmhook_self(hook_p hook);    /* if a node wants to kill a hook */
 1135 int     ng_rmnode_self(node_p here);    /* if a node wants to suicide */
 1136 int     ng_rmtype(struct ng_type *tp);
 1137 int     ng_snd_item(item_p item, int queue);
 1138 int     ng_send_fn(node_p node, hook_p hook, ng_item_fn *fn, void *arg1,
 1139         int arg2);
 1140 int     ng_send_fn1(node_p node, hook_p hook, ng_item_fn *fn, void *arg1,
 1141         int arg2, int flags);
 1142 int     ng_send_fn2(node_p node, hook_p hook, item_p pitem, ng_item_fn2 *fn,
 1143         void *arg1, int arg2, int flags);
 1144 int     ng_uncallout(struct callout *c, node_p node);
 1145 int     ng_callout(struct callout *c, node_p node, hook_p hook, int ticks,
 1146             ng_item_fn *fn, void * arg1, int arg2);
 1147 #define ng_callout_init(c)      callout_init(c)
 1148 
 1149 /* Flags for netgraph functions. */
 1150 #define NG_NOFLAGS      0x00000000      /* no special options */
 1151 #define NG_QUEUE        0x00000001      /* enqueue item, don't dispatch */
 1152 #define NG_WAITOK       0x00000002      /* use M_WAITOK, etc. */
 1153 /* XXXGL: NG_PROGRESS unused since ng_base.c rev. 1.136. Should be deleted? */
 1154 #define NG_PROGRESS     0x00000004      /* return EINPROGRESS if queued */
 1155 #define NG_REUSE_ITEM   0x00000008      /* supplied item should be reused */
 1156 
 1157 /*
 1158  * prototypes the user should DEFINITELY not use directly
 1159  */
 1160 void    ng_free_item(item_p item); /* Use NG_FREE_ITEM instead */
 1161 int     ng_mod_event(module_t mod, int what, void *arg);
 1162 
 1163 /*
 1164  * Tag definitions and constants
 1165  */
 1166 
 1167 #define NG_TAG_PRIO     1
 1168 
 1169 struct ng_tag_prio {
 1170         struct m_tag    tag;
 1171         char    priority;
 1172         char    discardability;
 1173 };
 1174 
 1175 #define NG_PRIO_CUTOFF          32
 1176 #define NG_PRIO_LINKSTATE       64
 1177 
 1178 /* Macros and declarations to keep compatibility with metadata, which
 1179  * is obsoleted now. To be deleted.
 1180  */
 1181 typedef void *meta_p;
 1182 #define _NGI_META(i)    NULL
 1183 #define NGI_META(i)     NULL
 1184 #define NG_FREE_META(meta)
 1185 #define NGI_GET_META(i,m)
 1186 #define ng_copy_meta(meta) NULL
 1187 
 1188 #endif /* _NETGRAPH_NETGRAPH_H_ */

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