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  */
  67
  68 /*
  69  * ng_gif_demux(4) netgraph node type
  70  *
  71  * Packets received on the "gif" hook have their type header removed
  72  * and are passed to the appropriate hook protocol hook.  Packets
  73  * recieved on a protocol hook have a type header added back and are
  74  * passed out the gif hook. The currently supported protocol hooks are:
  75  */
  76
  77 #include <sys/param.h>
  78 #include <sys/systm.h>
  79 #include <sys/kernel.h>
  80 #include <sys/malloc.h>
  81 #include <sys/ctype.h>
  82 #include <sys/mbuf.h>
  83 #include <sys/errno.h>
  84 #include <sys/socket.h>
  85
  86 #include <netgraph/ng_message.h>
  87 #include <netgraph/netgraph.h>
  88 #include <netgraph/ng_parse.h>
  89 #include <netgraph/ng_gif_demux.h>
  90
  91 #ifdef NG_SEPARATE_MALLOC
  92 MALLOC_DEFINE(M_NETGRAPH_GIF_DEMUX, "netgraph_gif_demux",
  93     "netgraph gif demux node");
  94 #else
  95 #define M_NETGRAPH_GIF_DEMUX M_NETGRAPH
  96 #endif
  97
  98 /* This struct describes one address family */
  99 struct iffam {
 100         sa_family_t     family;         /* Address family */
 101         const char      *hookname;      /* Name for hook */
 102 };
 103 typedef const struct iffam *iffam_p;
 104
 105 /* List of address families supported by our interface */
 106 const static struct iffam gFamilies[] = {
 107         { AF_INET,      NG_GIF_DEMUX_HOOK_INET  },
 108         { AF_INET6,     NG_GIF_DEMUX_HOOK_INET6 },
 109         { AF_APPLETALK, NG_GIF_DEMUX_HOOK_ATALK },
 110         { AF_IPX,       NG_GIF_DEMUX_HOOK_IPX   },
 111         { AF_ATM,       NG_GIF_DEMUX_HOOK_ATM   },
 112         { AF_NATM,      NG_GIF_DEMUX_HOOK_NATM  },
 113 };
 114 #define NUM_FAMILIES            (sizeof(gFamilies) / sizeof(*gFamilies))
 115
 116 /* Per-node private data */
 117 struct ng_gif_demux_private {
 118         node_p  node;                   /* Our netgraph node */
 119         hook_p  gif;                    /* The gif hook */
 120         hook_p  hooks[NUM_FAMILIES];    /* The protocol hooks */
 121 };
 122 typedef struct ng_gif_demux_private *priv_p;
 123
 124 /* Netgraph node methods */
 125 static ng_constructor_t ng_gif_demux_constructor;
 126 static ng_rcvmsg_t      ng_gif_demux_rcvmsg;
 127 static ng_shutdown_t    ng_gif_demux_shutdown;
 128 static ng_newhook_t     ng_gif_demux_newhook;
 129 static ng_rcvdata_t     ng_gif_demux_rcvdata;
 130 static ng_disconnect_t  ng_gif_demux_disconnect;
 131
 132 /* Helper stuff */
 133 static iffam_p  get_iffam_from_af(sa_family_t family);
 134 static iffam_p  get_iffam_from_hook(priv_p priv, hook_p hook);
 135 static iffam_p  get_iffam_from_name(const char *name);
 136 static hook_p   *get_hook_from_iffam(priv_p priv, iffam_p iffam);
 137
 138 /******************************************************************
 139                     NETGRAPH PARSE TYPES
 140 ******************************************************************/
 141
 142 /* List of commands and how to convert arguments to/from ASCII */
 143 static const struct ng_cmdlist ng_gif_demux_cmdlist[] = {
 144         { 0 }
 145 };
 146
 147 /* Node type descriptor */
 148 static struct ng_type ng_gif_demux_typestruct = {
 149         .version =      NG_ABI_VERSION,
 150         .name =         NG_GIF_DEMUX_NODE_TYPE,
 151         .constructor =  ng_gif_demux_constructor,
 152         .rcvmsg =       ng_gif_demux_rcvmsg,
 153         .shutdown =     ng_gif_demux_shutdown,
 154         .newhook =      ng_gif_demux_newhook,
 155         .rcvdata =      ng_gif_demux_rcvdata,
 156         .disconnect =   ng_gif_demux_disconnect,
 157         .cmdlist =      ng_gif_demux_cmdlist,
 158 };
 159 NETGRAPH_INIT(gif_demux, &ng_gif_demux_typestruct);
 160
 161 /************************************************************************
 162                     HELPER STUFF
 163  ************************************************************************/
 164
 165 /*
 166  * Get the family descriptor from the family ID
 167  */
 168 static __inline iffam_p
 169 get_iffam_from_af(sa_family_t family)
 170 {
 171         iffam_p iffam;
 172         int k;
 173
 174         for (k = 0; k < NUM_FAMILIES; k++) {
 175                 iffam = &gFamilies[k];
 176                 if (iffam->family == family)
 177                         return (iffam);
 178         }
 179         return (NULL);
 180 }
 181
 182 /*
 183  * Get the family descriptor from the hook
 184  */
 185 static __inline iffam_p
 186 get_iffam_from_hook(priv_p priv, hook_p hook)
 187 {
 188         int k;
 189
 190         for (k = 0; k < NUM_FAMILIES; k++)
 191                 if (priv->hooks[k] == hook)
 192                         return (&gFamilies[k]);
 193         return (NULL);
 194 }
 195
 196 /*
 197  * Get the hook from the iffam descriptor
 198  */
 199
 200 static __inline hook_p *
 201 get_hook_from_iffam(priv_p priv, iffam_p iffam)
 202 {
 203         return (&priv->hooks[iffam - gFamilies]);
 204 }
 205
 206 /*
 207  * Get the iffam descriptor from the name
 208  */
 209 static __inline iffam_p
 210 get_iffam_from_name(const char *name)
 211 {
 212         iffam_p iffam;
 213         int k;
 214
 215         for (k = 0; k < NUM_FAMILIES; k++) {
 216                 iffam = &gFamilies[k];
 217                 if (!strcmp(iffam->hookname, name))
 218                         return (iffam);
 219         }
 220         return (NULL);
 221 }
 222
 223 /******************************************************************
 224                     NETGRAPH NODE METHODS
 225 ******************************************************************/
 226
 227 /*
 228  * Node constructor
 229  */
 230 static int
 231 ng_gif_demux_constructor(node_p node)
 232 {
 233         priv_p priv;
 234
 235         /* Allocate and initialize private info */
 236         MALLOC(priv, priv_p, sizeof(*priv), M_NETGRAPH_GIF_DEMUX,
 237             M_NOWAIT | M_ZERO);
 238         if (priv == NULL)
 239                 return (ENOMEM);
 240         priv->node = node;
 241
 242         NG_NODE_SET_PRIVATE(node, priv);
 243
 244         /* Done */
 245         return (0);
 246 }
 247
 248 /*
 249  * Method for attaching a new hook
 250  */
 251 static  int
 252 ng_gif_demux_newhook(node_p node, hook_p hook, const char *name)
 253 {
 254         const priv_p priv = NG_NODE_PRIVATE(node);
 255         iffam_p iffam;
 256         hook_p *hookptr;
 257
 258         if (strcmp(NG_GIF_DEMUX_HOOK_GIF, name) == 0)
 259                 hookptr = &priv->gif;
 260         else {
 261                 iffam = get_iffam_from_name(name);
 262                 if (iffam == NULL)
 263                         return (EPFNOSUPPORT);
 264                 hookptr = get_hook_from_iffam(NG_NODE_PRIVATE(node), iffam);
 265         }
 266         if (*hookptr != NULL)
 267                 return (EISCONN);
 268         *hookptr = hook;
 269         return (0);
 270 }
 271
 272 /*
 273  * Receive a control message
 274  */
 275 static int
 276 ng_gif_demux_rcvmsg(node_p node, item_p item, hook_p lasthook)
 277 {
 278         struct ng_mesg *resp = NULL;
 279         int error = 0;
 280         struct ng_mesg *msg;
 281
 282         NGI_GET_MSG(item, msg);
 283         switch (msg->header.typecookie) {
 284         case NGM_GIF_DEMUX_COOKIE:
 285                 switch (msg->header.cmd) {
 286                 /* XXX: Add commands here. */
 287                 default:
 288                         error = EINVAL;
 289                         break;
 290                 }
 291                 break;
 292         default:
 293                 error = EINVAL;
 294                 break;
 295         }
 296
 297         /* Done */
 298         NG_RESPOND_MSG(error, node, item, resp);
 299         NG_FREE_MSG(msg);
 300         return (error);
 301 }
 302
 303 /*
 304  * Receive data on a hook
 305  */
 306 static int
 307 ng_gif_demux_rcvdata(hook_p hook, item_p item)
 308 {
 309         const node_p node = NG_HOOK_NODE(hook);
 310         const priv_p priv = NG_NODE_PRIVATE(node);
 311         iffam_p iffam;
 312         hook_p outhook;
 313         int error = 0;
 314         struct mbuf *m;
 315
 316         /* Pull the mbuf out of the item for processing. */
 317         NGI_GET_M(item, m);
 318
 319         if (hook == priv->gif) {
 320                 /*
 321                  * Pull off the address family header and find the
 322                  * output hook.
 323                  */
 324                 if (m->m_pkthdr.len < sizeof(sa_family_t)) {
 325                         NG_FREE_M(m);
 326                         NG_FREE_ITEM(item);
 327                         return (EINVAL);
 328                 }
 329                 if (m->m_len < sizeof(sa_family_t)
 330                     && (m = m_pullup(m, sizeof(sa_family_t))) == NULL) {
 331                         NG_FREE_ITEM(item);
 332                         return (ENOBUFS);
 333                 }
 334                 iffam = get_iffam_from_af(*mtod(m, sa_family_t *));
 335                 if (iffam == NULL) {
 336                         NG_FREE_M(m);
 337                         NG_FREE_ITEM(item);
 338                         return (EINVAL);
 339                 }
 340                 outhook = *get_hook_from_iffam(priv, iffam);
 341                 m_adj(m, sizeof(sa_family_t));
 342         } else {
 343                 /*
 344                  * Add address family header and set the output hook.
 345                  */
 346                 iffam = get_iffam_from_hook(priv, hook);
 347                 M_PREPEND(m, sizeof (iffam->family), M_DONTWAIT);
 348                 if (m == NULL) {
 349                         NG_FREE_M(m);
 350                         NG_FREE_ITEM(item);
 351                         return (ENOBUFS);
 352                 }
 353                 bcopy(&iffam->family, mtod(m, sa_family_t *),
 354                     sizeof(iffam->family));
 355                 outhook = priv->gif;
 356         }
 357
 358         /* Stuff the mbuf back in. */
 359         NGI_M(item) = m;
 360
 361         /* Deliver packet */
 362         NG_FWD_ITEM_HOOK(error, item, outhook);
 363         return (error);
 364 }
 365
 366 /*
 367  * Shutdown node
 368  */
 369 static int
 370 ng_gif_demux_shutdown(node_p node)
 371 {
 372         const priv_p priv = NG_NODE_PRIVATE(node);
 373
 374         FREE(priv, M_NETGRAPH_GIF_DEMUX);
 375         NG_NODE_SET_PRIVATE(node, NULL);
 376         NG_NODE_UNREF(node);
 377         return (0);
 378 }
 379
 380 /*
 381  * Hook disconnection.
 382  */
 383 static int
 384 ng_gif_demux_disconnect(hook_p hook)
 385 {
 386         const priv_p priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
 387         iffam_p iffam;
 388
 389         if (hook == priv->gif)
 390                 priv->gif = NULL;
 391         else {
 392                 iffam = get_iffam_from_hook(priv, hook);
 393                 if (iffam == NULL)
 394                         panic(__func__);
 395                 *get_hook_from_iffam(priv, iffam) = NULL;
 396         }
 397
 398         return (0);
 399 }