sys/netgraph/ng_atmllc.c

   1 /*
   2  * Copyright (c) 2003-2004 Benno Rice <benno@eloquent.com.au>
   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  ``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  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/systm.h>
  31 #include <sys/kernel.h>
  32 #include <sys/malloc.h>
  33 #include <sys/mbuf.h>
  34 #include <sys/socket.h>
  35 #include <sys/sockio.h>
  36
  37 #include <netgraph/ng_message.h>
  38 #include <netgraph/netgraph.h>
  39 #include <netgraph/ng_atmllc.h>
  40
  41 #include <net/if.h>
  42 #include <net/ethernet.h>       /* for M_HASFCS and ETHER_HDR_LEN */
  43 #include <net/if_atm.h>         /* for struct atmllc */
  44
  45 #define NG_ATMLLC_HEADER                "\252\252\3\0\200\302"
  46 #define NG_ATMLLC_HEADER_LEN            (sizeof(struct atmllc))
  47 #define NG_ATMLLC_TYPE_ETHERNET_FCS     0x0001
  48 #define NG_ATMLLC_TYPE_FDDI_FCS         0x0004
  49 #define NG_ATMLLC_TYPE_ETHERNET_NOFCS   0x0007
  50 #define NG_ATMLLC_TYPE_FDDI_NOFCS       0x000A
  51
  52 struct ng_atmllc_priv {
  53         hook_p          atm;
  54         hook_p          ether;
  55         hook_p          fddi;
  56 };
  57
  58 /* Netgraph methods. */
  59 static ng_constructor_t         ng_atmllc_constructor;
  60 static ng_shutdown_t            ng_atmllc_shutdown;
  61 static ng_rcvmsg_t              ng_atmllc_rcvmsg;
  62 static ng_newhook_t             ng_atmllc_newhook;
  63 static ng_rcvdata_t             ng_atmllc_rcvdata;
  64 static ng_disconnect_t          ng_atmllc_disconnect;
  65
  66 static struct ng_type ng_atmllc_typestruct = {
  67         NG_ABI_VERSION,
  68         NG_ATMLLC_NODE_TYPE,
  69         NULL,
  70         ng_atmllc_constructor,
  71         ng_atmllc_rcvmsg,
  72         ng_atmllc_shutdown,
  73         ng_atmllc_newhook,
  74         NULL,
  75         NULL,
  76         ng_atmllc_rcvdata,
  77         ng_atmllc_disconnect,
  78         NULL
  79 };
  80 NETGRAPH_INIT(atmllc, &ng_atmllc_typestruct);
  81
  82 static int
  83 ng_atmllc_constructor(node_p node)
  84 {
  85         struct  ng_atmllc_priv *priv;
  86
  87         MALLOC(priv, struct ng_atmllc_priv *, sizeof(*priv), M_NETGRAPH,
  88             M_NOWAIT | M_ZERO);
  89         if (priv == NULL) {
  90                 return (ENOMEM);
  91         }
  92
  93         NG_NODE_SET_PRIVATE(node, priv);
  94
  95         return (0);
  96 }
  97
  98 static int
  99 ng_atmllc_rcvmsg(node_p node, item_p item, hook_p lasthook)
 100 {
 101         struct  ng_mesg *msg;
 102         int     error;
 103
 104         error = 0;
 105         NGI_GET_MSG(item, msg);
 106         msg->header.flags |= NGF_RESP;
 107         NG_RESPOND_MSG(error, node, item, msg);
 108         return (error);
 109 }
 110
 111 static int
 112 ng_atmllc_shutdown(node_p node)
 113 {
 114         struct  ng_atmllc_priv *priv;
 115
 116         priv = NG_NODE_PRIVATE(node);
 117
 118         FREE(priv, M_NETGRAPH);
 119
 120         NG_NODE_UNREF(node);
 121
 122         return (0);
 123 }
 124
 125 static int
 126 ng_atmllc_newhook(node_p node, hook_p hook, const char *name)
 127 {
 128         struct  ng_atmllc_priv *priv;
 129
 130         priv = NG_NODE_PRIVATE(node);
 131
 132         if (strcmp(name, NG_ATMLLC_HOOK_ATM) == 0) {
 133                 if (priv->atm != NULL) {
 134                         return (EISCONN);
 135                 }
 136                 priv->atm = hook;
 137         } else if (strcmp(name, NG_ATMLLC_HOOK_ETHER) == 0) {
 138                 if (priv->ether != NULL) {
 139                         return (EISCONN);
 140                 }
 141                 priv->ether = hook;
 142         } else if (strcmp(name, NG_ATMLLC_HOOK_FDDI) == 0) {
 143                 if (priv->fddi != NULL) {
 144                         return (EISCONN);
 145                 }
 146                 priv->fddi = hook;
 147         } else {
 148                 return (EINVAL);
 149         }
 150
 151         return (0);
 152 }
 153
 154 static int
 155 ng_atmllc_rcvdata(hook_p hook, item_p item)
 156 {
 157         struct  ng_atmllc_priv *priv;
 158         struct  mbuf *m;
 159         struct  atmllc *hdr;
 160         hook_p  outhook;
 161         u_int   padding;
 162         int     error;
 163
 164         priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
 165         m = NGI_M(item);
 166         outhook = NULL;
 167         padding = 0;
 168
 169         if (hook == priv->atm) {
 170                 /* Ditch the psuedoheader. */
 171                 hdr = mtod(m, struct atmllc *);
 172                 /* m_adj(m, sizeof(struct atm_pseudohdr)); */
 173
 174                 /*
 175                  * Make sure we have the LLC and ethernet headers.
 176                  * The ethernet header size is slightly larger than the FDDI
 177                  * header, which is convenient.
 178                  */
 179                 if (m->m_len < sizeof(struct atmllc) + ETHER_HDR_LEN) {
 180                         m = m_pullup(m, sizeof(struct atmllc) + ETHER_HDR_LEN);
 181                         if (m == NULL) {
 182                                 return (ENOMEM);
 183                         }
 184                 }
 185
 186                 /* Decode the LLC header. */
 187                 hdr = mtod(m, struct atmllc *);
 188                 if (ATM_LLC_TYPE(hdr) == NG_ATMLLC_TYPE_ETHERNET_NOFCS) {
 189                         m->m_flags &= ~M_HASFCS;
 190                         outhook = priv->ether;
 191                         padding = 2;
 192                 } else if (ATM_LLC_TYPE(hdr) == NG_ATMLLC_TYPE_ETHERNET_FCS) {
 193                         m->m_flags |= M_HASFCS;
 194                         outhook = priv->ether;
 195                         padding = 2;
 196                 } else if (ATM_LLC_TYPE(hdr) == NG_ATMLLC_TYPE_FDDI_NOFCS) {
 197                         m->m_flags &= ~M_HASFCS;
 198                         outhook = priv->fddi;
 199                         padding = 3;
 200                 } else if (ATM_LLC_TYPE(hdr) == NG_ATMLLC_TYPE_FDDI_FCS) {
 201                         m->m_flags |= M_HASFCS;
 202                         outhook = priv->fddi;
 203                         padding = 3;
 204                 } else {
 205                         printf("ng_atmllc: unknown type: %x\n",
 206                             ATM_LLC_TYPE(hdr));
 207                 }
 208
 209                 /* Remove the LLC header and any padding*/
 210                 m_adj(m, sizeof(struct atmllc) + padding);
 211         } else if (hook == priv->ether) {
 212                 /* Add the LLC header */
 213                 M_PREPEND(m, NG_ATMLLC_HEADER_LEN + 2, M_DONTWAIT);
 214                 if (m == NULL) {
 215                         printf("ng_atmllc: M_PREPEND failed\n");
 216                         NG_FREE_ITEM(item);
 217                         return (ENOMEM);
 218                 }
 219                 hdr = mtod(m, struct atmllc *);
 220                 bzero((void *)hdr, sizeof(struct atmllc) + 2);
 221                 bcopy(NG_ATMLLC_HEADER, hdr->llchdr, 6);
 222                 if ((m->m_flags & M_HASFCS) != 0) {
 223                         ATM_LLC_SETTYPE(hdr, NG_ATMLLC_TYPE_ETHERNET_FCS);
 224                 } else {
 225                         ATM_LLC_SETTYPE(hdr, NG_ATMLLC_TYPE_ETHERNET_NOFCS);
 226                 }
 227                 outhook = priv->atm;
 228         } else if (hook == priv->fddi) {
 229                 /* Add the LLC header */
 230                 M_PREPEND(m, NG_ATMLLC_HEADER_LEN + 3, M_DONTWAIT);
 231                 if (m == NULL) {
 232                         printf("ng_atmllc: M_PREPEND failed\n");
 233                         NG_FREE_ITEM(item);
 234                         return (ENOMEM);
 235                 }
 236                 hdr = mtod(m, struct atmllc *);
 237                 bzero((void *)hdr, sizeof(struct atmllc) + 3);
 238                 bcopy(NG_ATMLLC_HEADER, hdr->llchdr, 6);
 239                 if ((m->m_flags & M_HASFCS) != 0) {
 240                         ATM_LLC_SETTYPE(hdr, NG_ATMLLC_TYPE_FDDI_FCS);
 241                 } else {
 242                         ATM_LLC_SETTYPE(hdr, NG_ATMLLC_TYPE_FDDI_NOFCS);
 243                 }
 244                 outhook = priv->atm;
 245         }
 246
 247         if (outhook == NULL) {
 248                 NG_FREE_ITEM(item);
 249                 return (0);
 250         }
 251
 252         NG_FWD_NEW_DATA(error, item, outhook, m);
 253         return (error);
 254 }
 255
 256 static int
 257 ng_atmllc_disconnect(hook_p hook)
 258 {
 259         node_p  node;
 260         struct  ng_atmllc_priv *priv;
 261
 262         node = NG_HOOK_NODE(hook);
 263         priv = NG_NODE_PRIVATE(node);
 264
 265         if (hook == priv->atm) {
 266                 priv->atm = NULL;
 267         } else if (hook == priv->ether) {
 268                 priv->ether = NULL;
 269         } else if (hook == priv->fddi) {
 270                 priv->fddi = NULL;
 271         }
 272
 273         if (NG_NODE_NUMHOOKS(node) == 0 && NG_NODE_IS_VALID(node)) {
 274                 ng_rmnode_self(node);
 275         }
 276
 277         return (0);
 278 }