sys/netgraph7/ng_hole.c

   1 /*
   2  * ng_hole.c
   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 Elisher <julian@freebsd.org>
  39  *
  40  * $FreeBSD: src/sys/netgraph/ng_hole.c,v 1.15 2005/12/09 07:09:44 ru Exp $
  41  * $DragonFly: src/sys/netgraph7/ng_hole.c,v 1.2 2008/06/26 23:05:35 dillon Exp $
  42  * $Whistle: ng_hole.c,v 1.10 1999/11/01 09:24:51 julian Exp $
  43  */
  44
  45 /*
  46  * This node is a 'black hole' that simply discards everything it receives
  47  */
  48
  49 #include <sys/param.h>
  50 #include <sys/systm.h>
  51 #include <sys/kernel.h>
  52 #include <sys/malloc.h>
  53 #include <sys/mbuf.h>
  54 #include "ng_message.h"
  55 #include "netgraph.h"
  56 #include "ng_parse.h"
  57 #include "ng_hole.h"
  58
  59 /* Per hook private info. */
  60 struct ng_hole_hookinfo {
  61         struct ng_hole_hookstat stats;
  62 };
  63 typedef struct ng_hole_hookinfo *hinfo_p;
  64
  65 /* Parse type for struct ng_hole_hookstat. */
  66 static const struct ng_parse_struct_field ng_hole_hookstat_type_fields[] =
  67         NG_HOLE_HOOKSTAT_TYPE_INFO;
  68 static const struct ng_parse_type ng_hole_hookstat_type = {
  69         &ng_parse_struct_type,
  70         &ng_hole_hookstat_type_fields
  71 };
  72
  73 /* List of commands and how to convert arguments to/from ASCII. */
  74 static const struct ng_cmdlist ng_hole_cmdlist[] = {
  75         {
  76           NGM_HOLE_COOKIE,
  77           NGM_HOLE_GET_STATS,
  78           "getstats",
  79           &ng_parse_hookbuf_type,
  80           &ng_hole_hookstat_type
  81         },
  82         {
  83           NGM_HOLE_COOKIE,
  84           NGM_HOLE_CLR_STATS,
  85           "clrstats",
  86           &ng_parse_hookbuf_type,
  87           NULL
  88         },
  89         {
  90           NGM_HOLE_COOKIE,
  91           NGM_HOLE_GETCLR_STATS,
  92           "getclrstats",
  93           &ng_parse_hookbuf_type,
  94           &ng_hole_hookstat_type
  95         },
  96         { 0 }
  97 };
  98
  99 /* Netgraph methods */
 100 static ng_constructor_t ngh_cons;
 101 static ng_rcvmsg_t      ngh_rcvmsg;
 102 static ng_newhook_t     ngh_newhook;
 103 static ng_rcvdata_t     ngh_rcvdata;
 104 static ng_disconnect_t  ngh_disconnect;
 105
 106 static struct ng_type typestruct = {
 107         .version =      NG_ABI_VERSION,
 108         .name =         NG_HOLE_NODE_TYPE,
 109         .constructor =  ngh_cons,
 110         .rcvmsg =       ngh_rcvmsg,
 111         .newhook =      ngh_newhook,
 112         .rcvdata =      ngh_rcvdata,
 113         .disconnect =   ngh_disconnect,
 114         .cmdlist =      ng_hole_cmdlist,
 115 };
 116 NETGRAPH_INIT(hole, &typestruct);
 117
 118 /*
 119  * Be obliging. but no work to do.
 120  */
 121 static int
 122 ngh_cons(node_p node)
 123 {
 124         return(0);
 125 }
 126
 127 /*
 128  * Add a hook.
 129  */
 130 static int
 131 ngh_newhook(node_p node, hook_p hook, const char *name)
 132 {
 133         hinfo_p hip;
 134
 135         /* Create hook private structure. */
 136         MALLOC(hip, hinfo_p, sizeof(*hip), M_NETGRAPH, M_WAITOK | M_NULLOK | M_ZERO);
 137         if (hip == NULL)
 138                 return (ENOMEM);
 139         NG_HOOK_SET_PRIVATE(hook, hip);
 140         return (0);
 141 }
 142
 143 /*
 144  * Receive a control message.
 145  */
 146 static int
 147 ngh_rcvmsg(node_p node, item_p item, hook_p lasthook)
 148 {
 149         struct ng_mesg *msg;
 150         struct ng_mesg *resp = NULL;
 151         int error = 0;
 152         struct ng_hole_hookstat *stats;
 153         hook_p hook;
 154
 155         NGI_GET_MSG(item, msg);
 156         switch (msg->header.typecookie) {
 157         case NGM_HOLE_COOKIE:
 158                 switch (msg->header.cmd) {
 159                 case NGM_HOLE_GET_STATS:
 160                 case NGM_HOLE_CLR_STATS:
 161                 case NGM_HOLE_GETCLR_STATS:
 162                         /* Sanity check. */
 163                         if (msg->header.arglen != NG_HOOKSIZ) {
 164                                 error = EINVAL;
 165                                 break;
 166                         }
 167                         /* Find hook. */
 168                         hook = ng_findhook(node, (char *)msg->data);
 169                         if (hook == NULL) {
 170                                 error = ENOENT;
 171                                 break;
 172                         }
 173                         stats = &((hinfo_p)NG_HOOK_PRIVATE(hook))->stats;
 174                         /* Build response (if desired). */
 175                         if (msg->header.cmd != NGM_HOLE_CLR_STATS) {
 176                                 NG_MKRESPONSE(resp, msg, sizeof(*stats),
 177                                     M_WAITOK | M_NULLOK);
 178                                 if (resp == NULL) {
 179                                         error = ENOMEM;
 180                                         break;
 181                                 }
 182                                 bcopy(stats, resp->data, sizeof(*stats));
 183                         }
 184                         /* Clear stats (if desired). */
 185                         if (msg->header.cmd != NGM_HOLE_GET_STATS)
 186                                 bzero(stats, sizeof(*stats));
 187                         break;
 188                 default:                /* Unknown command. */
 189                         error = EINVAL;
 190                         break;
 191                 }
 192                 break;
 193         default:                        /* Unknown type cookie. */
 194                 error = EINVAL;
 195                 break;
 196         }
 197         NG_RESPOND_MSG(error, node, item, resp);
 198         NG_FREE_MSG(msg);
 199         return (error);
 200 }
 201
 202 /*
 203  * Receive data
 204  */
 205 static int
 206 ngh_rcvdata(hook_p hook, item_p item)
 207 {
 208         const hinfo_p hip = NG_HOOK_PRIVATE(hook);
 209
 210         hip->stats.frames++;
 211         hip->stats.octets += NGI_M(item)->m_pkthdr.len;
 212         NG_FREE_ITEM(item);
 213         return 0;
 214 }
 215
 216 /*
 217  * Hook disconnection
 218  */
 219 static int
 220 ngh_disconnect(hook_p hook)
 221 {
 222
 223         FREE(NG_HOOK_PRIVATE(hook), M_NETGRAPH);
 224         NG_HOOK_SET_PRIVATE(hook, NULL);
 225         if (NG_NODE_NUMHOOKS(NG_HOOK_NODE(hook)) == 0)
 226                 ng_rmnode_self(NG_HOOK_NODE(hook));
 227         return (0);
 228 }