sys/netgraph7/ng_gif_demux.c

   1 /*
   2  * ng_gif_demux.c
   3  */
   4
   5 /*-
   6  * Copyright 2001 The Aerospace Corporation.  All rights reserved.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  *
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions, and the following disclaimer.
  14  * 2. Redistributions in binary form must reproduce the above copyright
  15  *    notice, this list of conditions, and the following disclaimer in the
  16  *    documentation and/or other materials provided with the distribution.
  17  * 3. The name of The Aerospace Corporation may not be used to endorse or
  18  *    promote products derived from this software.
  19  *
  20  * THIS SOFTWARE IS PROVIDED BY THE AEROSPACE CORPORATION ``AS IS'' AND
  21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AEROSPACE CORPORATION BE LIABLE
  24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  30  * SUCH DAMAGE.
  31  *
  32  *
  33  * Copyright (c) 1996-1999 Whistle Communications, Inc.
  34  * All rights reserved.
  35  *
  36  * Subject to the following obligations and disclaimer of warranty, use and
  37  * redistribution of this software, in source or object code forms, with or
  38  * without modifications are expressly permitted by Whistle Communications;
  39  * provided, however, that:
  40  * 1. Any and all reproductions of the source or object code must include the
  41  *    copyright notice above and the following disclaimer of warranties; and
  42  * 2. No rights are granted, in any manner or form, to use Whistle
  43  *    Communications, Inc. trademarks, including the mark "WHISTLE
  44  *    COMMUNICATIONS" on advertising, endorsements, or otherwise except as
  45  *    such appears in the above copyright notice or in the software.
  46  *
  47  * THIS SOFTWARE IS BEING PROVIDED BY WHISTLE COMMUNICATIONS "AS IS", AND
  48  * TO THE MAXIMUM EXTENT PERMITTED BY LAW, WHISTLE COMMUNICATIONS MAKES NO
  49  * REPRESENTATIONS OR WARRANTIES, EXPRESS OR IMPLIED, REGARDING THIS SOFTWARE,
  50  * INCLUDING WITHOUT LIMITATION, ANY AND ALL IMPLIED WARRANTIES OF
  51  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.
  52  * WHISTLE COMMUNICATIONS DOES NOT WARRANT, GUARANTEE, OR MAKE ANY
  53  * REPRESENTATIONS REGARDING THE USE OF, OR THE RESULTS OF THE USE OF THIS
  54  * SOFTWARE IN TERMS OF ITS CORRECTNESS, ACCURACY, RELIABILITY OR OTHERWISE.
  55  * IN NO EVENT SHALL WHISTLE COMMUNICATIONS BE LIABLE FOR ANY DAMAGES
  56  * RESULTING FROM OR ARISING OUT OF ANY USE OF THIS SOFTWARE, INCLUDING
  57  * WITHOUT LIMITATION, ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
  58  * PUNITIVE, OR CONSEQUENTIAL DAMAGES, PROCUREMENT OF SUBSTITUTE GOODS OR
  59  * SERVICES, LOSS OF USE, DATA OR PROFITS, HOWEVER CAUSED AND UNDER ANY
  60  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  61  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  62  * THIS SOFTWARE, EVEN IF WHISTLE COMMUNICATIONS IS ADVISED OF THE POSSIBILITY
  63  * OF SUCH DAMAGE.
  64  *
  65  * $FreeBSD: src/sys/netgraph/ng_gif_demux.c,v 1.10 2005/01/07 01:45:39 imp Exp $
  66  * $DragonFly: src/sys/netgraph7/ng_gif_demux.c,v 1.2 2008/06/26 23:05:35 dillon Exp $
  67  */
  68
  69 /*
  70  * ng_gif_demux(4) netgraph node type
  71  *
  72  * Packets received on the "gif" hook have their type header removed
  73  * and are passed to the appropriate hook protocol hook.  Packets
  74  * recieved on a protocol hook have a type header added back and are
  75  * passed out the gif hook. The currently supported protocol hooks are:
  76  */
  77
  78 #include <sys/param.h>
  79 #include <sys/systm.h>
  80 #include <sys/kernel.h>
  81 #include <sys/malloc.h>
  82 #include <sys/ctype.h>
  83 #include <sys/mbuf.h>
  84 #include <sys/errno.h>
  85 #include <sys/socket.h>
  86
  87 #include "ng_message.h"
  88 #include "netgraph.h"
  89 #include "ng_parse.h"
  90 #include "ng_gif_demux.h"
  91
  92 #ifdef NG_SEPARATE_MALLOC
  93 MALLOC_DEFINE(M_NETGRAPH_GIF_DEMUX, "netgraph_gif_demux",
  94     "netgraph gif demux node");
  95 #else
  96 #define M_NETGRAPH_GIF_DEMUX M_NETGRAPH
  97 #endif
  98
  99 /* This struct describes one address family */
 100 struct iffam {
 101         sa_family_t     family;         /* Address family */
 102         const char      *hookname;      /* Name for hook */
 103 };
 104 typedef const struct iffam *iffam_p;
 105
 106 /* List of address families supported by our interface */
 107 const static struct iffam gFamilies[] = {
 108         { AF_INET,      NG_GIF_DEMUX_HOOK_INET  },
 109         { AF_INET6,     NG_GIF_DEMUX_HOOK_INET6 },
 110         { AF_APPLETALK, NG_GIF_DEMUX_HOOK_ATALK },
 111         { AF_IPX,       NG_GIF_DEMUX_HOOK_IPX   },
 112         { AF_ATM,       NG_GIF_DEMUX_HOOK_ATM   },
 113         { AF_NATM,      NG_GIF_DEMUX_HOOK_NATM  },
 114 };
 115 #define NUM_FAMILIES            (sizeof(gFamilies) / sizeof(*gFamilies))
 116
 117 /* Per-node private data */
 118 struct ng_gif_demux_private {
 119         node_p  node;                   /* Our netgraph node */
 120         hook_p  gif;                    /* The gif hook */
 121         hook_p  hooks[NUM_FAMILIES];    /* The protocol hooks */
 122 };
 123 typedef struct ng_gif_demux_private *priv_p;
 124
 125 /* Netgraph node methods */
 126 static ng_constructor_t ng_gif_demux_constructor;
 127 static ng_rcvmsg_t      ng_gif_demux_rcvmsg;
 128 static ng_shutdown_t    ng_gif_demux_shutdown;
 129 static ng_newhook_t     ng_gif_demux_newhook;
 130 static ng_rcvdata_t     ng_gif_demux_rcvdata;
 131 static ng_disconnect_t  ng_gif_demux_disconnect;
 132
 133 /* Helper stuff */
 134 static iffam_p  get_iffam_from_af(sa_family_t family);
 135 static iffam_p  get_iffam_from_hook(priv_p priv, hook_p hook);
 136 static iffam_p  get_iffam_from_name(const char *name);
 137 static hook_p   *get_hook_from_iffam(priv_p priv, iffam_p iffam);
 138
 139 /******************************************************************
 140                     NETGRAPH PARSE TYPES
 141 ******************************************************************/
 142
 143 /* List of commands and how to convert arguments to/from ASCII */
 144 static const struct ng_cmdlist ng_gif_demux_cmdlist[] = {
 145         { 0 }
 146 };
 147
 148 /* Node type descriptor */
 149 static struct ng_type ng_gif_demux_typestruct = {
 150         .version =      NG_ABI_VERSION,
 151         .name =         NG_GIF_DEMUX_NODE_TYPE,
 152         .constructor =  ng_gif_demux_constructor,
 153         .rcvmsg =       ng_gif_demux_rcvmsg,
 154         .shutdown =     ng_gif_demux_shutdown,
 155         .newhook =      ng_gif_demux_newhook,
 156         .rcvdata =      ng_gif_demux_rcvdata,
 157         .disconnect =   ng_gif_demux_disconnect,
 158         .cmdlist =      ng_gif_demux_cmdlist,
 159 };
 160 NETGRAPH_INIT(gif_demux, &ng_gif_demux_typestruct);
 161
 162 /************************************************************************
 163                     HELPER STUFF
 164  ************************************************************************/
 165
 166 /*
 167  * Get the family descriptor from the family ID
 168  */
 169 static __inline iffam_p
 170 get_iffam_from_af(sa_family_t family)
 171 {
 172         iffam_p iffam;
 173         int k;
 174
 175         for (k = 0; k < NUM_FAMILIES; k++) {
 176                 iffam = &gFamilies[k];
 177                 if (iffam->family == family)
 178                         return (iffam);
 179         }
 180         return (NULL);
 181 }
 182
 183 /*
 184  * Get the family descriptor from the hook
 185  */
 186 static __inline iffam_p
 187 get_iffam_from_hook(priv_p priv, hook_p hook)
 188 {
 189         int k;
 190
 191         for (k = 0; k < NUM_FAMILIES; k++)
 192                 if (priv->hooks[k] == hook)
 193                         return (&gFamilies[k]);
 194         return (NULL);
 195 }
 196
 197 /*
 198  * Get the hook from the iffam descriptor
 199  */
 200
 201 static __inline hook_p *
 202 get_hook_from_iffam(priv_p priv, iffam_p iffam)
 203 {
 204         return (&priv->hooks[iffam - gFamilies]);
 205 }
 206
 207 /*
 208  * Get the iffam descriptor from the name
 209  */
 210 static __inline iffam_p
 211 get_iffam_from_name(const char *name)
 212 {
 213         iffam_p iffam;
 214         int k;
 215
 216         for (k = 0; k < NUM_FAMILIES; k++) {
 217                 iffam = &gFamilies[k];
 218                 if (!strcmp(iffam->hookname, name))
 219                         return (iffam);
 220         }
 221         return (NULL);
 222 }
 223
 224 /******************************************************************
 225                     NETGRAPH NODE METHODS
 226 ******************************************************************/
 227
 228 /*
 229  * Node constructor
 230  */
 231 static int
 232 ng_gif_demux_constructor(node_p node)
 233 {
 234         priv_p priv;
 235
 236         /* Allocate and initialize private info */
 237         MALLOC(priv, priv_p, sizeof(*priv), M_NETGRAPH_GIF_DEMUX,
 238             M_WAITOK | M_NULLOK | M_ZERO);
 239         if (priv == NULL)
 240                 return (ENOMEM);
 241         priv->node = node;
 242
 243         NG_NODE_SET_PRIVATE(node, priv);
 244
 245         /* Done */
 246         return (0);
 247 }
 248
 249 /*
 250  * Method for attaching a new hook
 251  */
 252 static  int
 253 ng_gif_demux_newhook(node_p node, hook_p hook, const char *name)
 254 {
 255         const priv_p priv = NG_NODE_PRIVATE(node);
 256         iffam_p iffam;
 257         hook_p *hookptr;
 258
 259         if (strcmp(NG_GIF_DEMUX_HOOK_GIF, name) == 0)
 260                 hookptr = &priv->gif;
 261         else {
 262                 iffam = get_iffam_from_name(name);
 263                 if (iffam == NULL)
 264                         return (EPFNOSUPPORT);
 265                 hookptr = get_hook_from_iffam(NG_NODE_PRIVATE(node), iffam);
 266         }
 267         if (*hookptr != NULL)
 268                 return (EISCONN);
 269         *hookptr = hook;
 270         return (0);
 271 }
 272
 273 /*
 274  * Receive a control message
 275  */
 276 static int
 277 ng_gif_demux_rcvmsg(node_p node, item_p item, hook_p lasthook)
 278 {
 279         struct ng_mesg *resp = NULL;
 280         int error = 0;
 281         struct ng_mesg *msg;
 282
 283         NGI_GET_MSG(item, msg);
 284         switch (msg->header.typecookie) {
 285         case NGM_GIF_DEMUX_COOKIE:
 286                 switch (msg->header.cmd) {
 287                 /* XXX: Add commands here. */
 288                 default:
 289                         error = EINVAL;
 290                         break;
 291                 }
 292                 break;
 293         default:
 294                 error = EINVAL;
 295                 break;
 296         }
 297
 298         /* Done */
 299         NG_RESPOND_MSG(error, node, item, resp);
 300         NG_FREE_MSG(msg);
 301         return (error);
 302 }
 303
 304 /*
 305  * Receive data on a hook
 306  */
 307 static int
 308 ng_gif_demux_rcvdata(hook_p hook, item_p item)
 309 {
 310         const node_p node = NG_HOOK_NODE(hook);
 311         const priv_p priv = NG_NODE_PRIVATE(node);
 312         iffam_p iffam;
 313         hook_p outhook;
 314         int error = 0;
 315         struct mbuf *m;
 316
 317         /* Pull the mbuf out of the item for processing. */
 318         NGI_GET_M(item, m);
 319
 320         if (hook == priv->gif) {
 321                 /*
 322                  * Pull off the address family header and find the
 323                  * output hook.
 324                  */
 325                 if (m->m_pkthdr.len < sizeof(sa_family_t)) {
 326                         NG_FREE_M(m);
 327                         NG_FREE_ITEM(item);
 328                         return (EINVAL);
 329                 }
 330                 if (m->m_len < sizeof(sa_family_t)
 331                     && (m = m_pullup(m, sizeof(sa_family_t))) == NULL) {
 332                         NG_FREE_ITEM(item);
 333                         return (ENOBUFS);
 334                 }
 335                 iffam = get_iffam_from_af(*mtod(m, sa_family_t *));
 336                 if (iffam == NULL) {
 337                         NG_FREE_M(m);
 338                         NG_FREE_ITEM(item);
 339                         return (EINVAL);
 340                 }
 341                 outhook = *get_hook_from_iffam(priv, iffam);
 342                 m_adj(m, sizeof(sa_family_t));
 343         } else {
 344                 /*
 345                  * Add address family header and set the output hook.
 346                  */
 347                 iffam = get_iffam_from_hook(priv, hook);
 348                 M_PREPEND(m, sizeof (iffam->family), MB_DONTWAIT);
 349                 if (m == NULL) {
 350                         NG_FREE_M(m);
 351                         NG_FREE_ITEM(item);
 352                         return (ENOBUFS);
 353                 }
 354                 bcopy(&iffam->family, mtod(m, sa_family_t *),
 355                     sizeof(iffam->family));
 356                 outhook = priv->gif;
 357         }
 358
 359         /* Stuff the mbuf back in. */
 360         NGI_M(item) = m;
 361
 362         /* Deliver packet */
 363         NG_FWD_ITEM_HOOK(error, item, outhook);
 364         return (error);
 365 }
 366
 367 /*
 368  * Shutdown node
 369  */
 370 static int
 371 ng_gif_demux_shutdown(node_p node)
 372 {
 373         const priv_p priv = NG_NODE_PRIVATE(node);
 374
 375         FREE(priv, M_NETGRAPH_GIF_DEMUX);
 376         NG_NODE_SET_PRIVATE(node, NULL);
 377         NG_NODE_UNREF(node);
 378         return (0);
 379 }
 380
 381 /*
 382  * Hook disconnection.
 383  */
 384 static int
 385 ng_gif_demux_disconnect(hook_p hook)
 386 {
 387         const priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
 388         iffam_p iffam;
 389
 390         if (hook == priv->gif)
 391                 priv->gif = NULL;
 392         else {
 393                 iffam = get_iffam_from_hook(priv, hook);
 394                 if (iffam == NULL)
 395                         panic(__func__);
 396                 *get_hook_from_iffam(priv, iffam) = NULL;
 397         }
 398
 399         return (0);
 400 }