sys/netgraph/ng_hub.c

   1 /*-
   2  * Copyright (c) 2004 Ruslan Ermilov
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  *
  14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  24  * SUCH DAMAGE.
  25  *
  26  * $FreeBSD$
  27  */
  28
  29 #include <sys/param.h>
  30 #include <sys/errno.h>
  31 #include <sys/kernel.h>
  32 #include <sys/mbuf.h>
  33 #include <sys/systm.h>
  34
  35 #include <netgraph/ng_message.h>
  36 #include <netgraph/ng_hub.h>
  37 #include <netgraph/netgraph.h>
  38
  39 #ifdef NG_SEPARATE_MALLOC
  40 static MALLOC_DEFINE(M_NETGRAPH_HUB, "netgraph_hub", "netgraph hub node");
  41 #else
  42 #define M_NETGRAPH_HUB M_NETGRAPH
  43 #endif
  44
  45 /* Per-node private data */
  46 struct ng_hub_private {
  47         int             persistent;     /* can exist w/o hooks */
  48 };
  49 typedef struct ng_hub_private *priv_p;
  50
  51 /* Netgraph node methods */
  52 static ng_constructor_t ng_hub_constructor;
  53 static ng_rcvmsg_t      ng_hub_rcvmsg;
  54 static ng_shutdown_t    ng_hub_shutdown;
  55 static ng_rcvdata_t     ng_hub_rcvdata;
  56 static ng_disconnect_t  ng_hub_disconnect;
  57
  58 /* List of commands and how to convert arguments to/from ASCII */
  59 static const struct ng_cmdlist ng_hub_cmdlist[] = {
  60         {
  61                 NGM_HUB_COOKIE,
  62                 NGM_HUB_SET_PERSISTENT,
  63                 "setpersistent",
  64                 NULL,
  65                 NULL
  66         },
  67         { 0 }
  68 };
  69
  70 static struct ng_type ng_hub_typestruct = {
  71         .version =      NG_ABI_VERSION,
  72         .name =         NG_HUB_NODE_TYPE,
  73         .constructor =  ng_hub_constructor,
  74         .rcvmsg =       ng_hub_rcvmsg,
  75         .shutdown =     ng_hub_shutdown,
  76         .rcvdata =      ng_hub_rcvdata,
  77         .disconnect =   ng_hub_disconnect,
  78         .cmdlist =      ng_hub_cmdlist,
  79 };
  80 NETGRAPH_INIT(hub, &ng_hub_typestruct);
  81
  82
  83 static int
  84 ng_hub_constructor(node_p node)
  85 {
  86         priv_p priv;
  87
  88         /* Allocate and initialize private info */
  89         priv = malloc(sizeof(*priv), M_NETGRAPH_HUB, M_WAITOK | M_ZERO);
  90
  91         NG_NODE_SET_PRIVATE(node, priv);
  92         return (0);
  93 }
  94
  95 /*
  96  * Receive a control message
  97  */
  98 static int
  99 ng_hub_rcvmsg(node_p node, item_p item, hook_p lasthook)
 100 {
 101         const priv_p priv = NG_NODE_PRIVATE(node);
 102         int error = 0;
 103         struct ng_mesg *msg;
 104
 105         NGI_GET_MSG(item, msg);
 106         if (msg->header.typecookie == NGM_HUB_COOKIE &&
 107             msg->header.cmd == NGM_HUB_SET_PERSISTENT) {
 108                 priv->persistent = 1;
 109         } else {
 110                 error = EINVAL;
 111         }
 112
 113         NG_FREE_MSG(msg);
 114         return (error);
 115 }
 116
 117 static int
 118 ng_hub_rcvdata(hook_p hook, item_p item)
 119 {
 120         const node_p node = NG_HOOK_NODE(hook);
 121         int error = 0;
 122         hook_p hook2;
 123         struct mbuf * const m = NGI_M(item), *m2;
 124         int nhooks;
 125
 126         if ((nhooks = NG_NODE_NUMHOOKS(node)) == 1) {
 127                 NG_FREE_ITEM(item);
 128                 return (0);
 129         }
 130         LIST_FOREACH(hook2, &node->nd_hooks, hk_hooks) {
 131                 if (hook2 == hook)
 132                         continue;
 133                 if (--nhooks == 1)
 134                         NG_FWD_ITEM_HOOK(error, item, hook2);
 135                 else {
 136                         if ((m2 = m_dup(m, M_NOWAIT)) == NULL) {
 137                                 NG_FREE_ITEM(item);
 138                                 return (ENOBUFS);
 139                         }
 140                         NG_SEND_DATA_ONLY(error, hook2, m2);
 141                         if (error)
 142                                 continue;       /* don't give up */
 143                 }
 144         }
 145
 146         return (error);
 147 }
 148
 149 /*
 150  * Shutdown node
 151  */
 152 static int
 153 ng_hub_shutdown(node_p node)
 154 {
 155         const priv_p priv = NG_NODE_PRIVATE(node);
 156
 157         free(priv, M_NETGRAPH_HUB);
 158         NG_NODE_SET_PRIVATE(node, NULL);
 159         NG_NODE_UNREF(node);
 160         return (0);
 161 }
 162
 163 static int
 164 ng_hub_disconnect(hook_p hook)
 165 {
 166         const priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
 167
 168         if (NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0 &&
 169             NG_NODE_IS_VALID(NG_HOOK_NODE(hook)) && !priv->persistent)
 170                 ng_rmnode_self(NG_HOOK_NODE(hook));
 171         return (0);
 172 }