sys/netgraph7/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: src/sys/netgraph/ng_atmllc.c,v 1.3 2005/01/07 01:45:39 imp Exp $
  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         .version =      NG_ABI_VERSION,
  68         .name =         NG_ATMLLC_NODE_TYPE,
  69         .constructor =  ng_atmllc_constructor,
  70         .rcvmsg =       ng_atmllc_rcvmsg,
  71         .shutdown =     ng_atmllc_shutdown,
  72         .newhook =      ng_atmllc_newhook,
  73         .rcvdata =      ng_atmllc_rcvdata,
  74         .disconnect =   ng_atmllc_disconnect,
  75 };
  76 NETGRAPH_INIT(atmllc, &ng_atmllc_typestruct);
  77
  78 static int
  79 ng_atmllc_constructor(node_p node)
  80 {
  81         struct  ng_atmllc_priv *priv;
  82
  83         MALLOC(priv, struct ng_atmllc_priv *, sizeof(*priv), M_NETGRAPH,
  84             M_NOWAIT | M_ZERO);
  85         if (priv == NULL) {
  86                 return (ENOMEM);
  87         }
  88
  89         NG_NODE_SET_PRIVATE(node, priv);
  90
  91         return (0);
  92 }
  93
  94 static int
  95 ng_atmllc_rcvmsg(node_p node, item_p item, hook_p lasthook)
  96 {
  97         struct  ng_mesg *msg;
  98         int     error;
  99
 100         error = 0;
 101         NGI_GET_MSG(item, msg);
 102         msg->header.flags |= NGF_RESP;
 103         NG_RESPOND_MSG(error, node, item, msg);
 104         return (error);
 105 }
 106
 107 static int
 108 ng_atmllc_shutdown(node_p node)
 109 {
 110         struct  ng_atmllc_priv *priv;
 111
 112         priv = NG_NODE_PRIVATE(node);
 113
 114         FREE(priv, M_NETGRAPH);
 115
 116         NG_NODE_UNREF(node);
 117
 118         return (0);
 119 }
 120
 121 static int
 122 ng_atmllc_newhook(node_p node, hook_p hook, const char *name)
 123 {
 124         struct  ng_atmllc_priv *priv;
 125
 126         priv = NG_NODE_PRIVATE(node);
 127
 128         if (strcmp(name, NG_ATMLLC_HOOK_ATM) == 0) {
 129                 if (priv->atm != NULL) {
 130                         return (EISCONN);
 131                 }
 132                 priv->atm = hook;
 133         } else if (strcmp(name, NG_ATMLLC_HOOK_ETHER) == 0) {
 134                 if (priv->ether != NULL) {
 135                         return (EISCONN);
 136                 }
 137                 priv->ether = hook;
 138         } else if (strcmp(name, NG_ATMLLC_HOOK_FDDI) == 0) {
 139                 if (priv->fddi != NULL) {
 140                         return (EISCONN);
 141                 }
 142                 priv->fddi = hook;
 143         } else {
 144                 return (EINVAL);
 145         }
 146
 147         return (0);
 148 }
 149
 150 static int
 151 ng_atmllc_rcvdata(hook_p hook, item_p item)
 152 {
 153         struct  ng_atmllc_priv *priv;
 154         struct  mbuf *m;
 155         struct  atmllc *hdr;
 156         hook_p  outhook;
 157         u_int   padding;
 158         int     error;
 159
 160         priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
 161         m = NGI_M(item);
 162         outhook = NULL;
 163         padding = 0;
 164
 165         if (hook == priv->atm) {
 166                 /* Ditch the psuedoheader. */
 167                 hdr = mtod(m, struct atmllc *);
 168                 /* m_adj(m, sizeof(struct atm_pseudohdr)); */
 169
 170                 /*
 171                  * Make sure we have the LLC and ethernet headers.
 172                  * The ethernet header size is slightly larger than the FDDI
 173                  * header, which is convenient.
 174                  */
 175                 if (m->m_len < sizeof(struct atmllc) + ETHER_HDR_LEN) {
 176                         m = m_pullup(m, sizeof(struct atmllc) + ETHER_HDR_LEN);
 177                         if (m == NULL) {
 178                                 return (ENOMEM);
 179                         }
 180                 }
 181
 182                 /* Decode the LLC header. */
 183                 hdr = mtod(m, struct atmllc *);
 184                 if (ATM_LLC_TYPE(hdr) == NG_ATMLLC_TYPE_ETHERNET_NOFCS) {
 185                         m->m_flags &= ~M_HASFCS;
 186                         outhook = priv->ether;
 187                         padding = 2;
 188                 } else if (ATM_LLC_TYPE(hdr) == NG_ATMLLC_TYPE_ETHERNET_FCS) {
 189                         m->m_flags |= M_HASFCS;
 190                         outhook = priv->ether;
 191                         padding = 2;
 192                 } else if (ATM_LLC_TYPE(hdr) == NG_ATMLLC_TYPE_FDDI_NOFCS) {
 193                         m->m_flags &= ~M_HASFCS;
 194                         outhook = priv->fddi;
 195                         padding = 3;
 196                 } else if (ATM_LLC_TYPE(hdr) == NG_ATMLLC_TYPE_FDDI_FCS) {
 197                         m->m_flags |= M_HASFCS;
 198                         outhook = priv->fddi;
 199                         padding = 3;
 200                 } else {
 201                         printf("ng_atmllc: unknown type: %x\n",
 202                             ATM_LLC_TYPE(hdr));
 203                 }
 204
 205                 /* Remove the LLC header and any padding*/
 206                 m_adj(m, sizeof(struct atmllc) + padding);
 207         } else if (hook == priv->ether) {
 208                 /* Add the LLC header */
 209                 M_PREPEND(m, NG_ATMLLC_HEADER_LEN + 2, M_DONTWAIT);
 210                 if (m == NULL) {
 211                         printf("ng_atmllc: M_PREPEND failed\n");
 212                         NG_FREE_ITEM(item);
 213                         return (ENOMEM);
 214                 }
 215                 hdr = mtod(m, struct atmllc *);
 216                 bzero((void *)hdr, sizeof(struct atmllc) + 2);
 217                 bcopy(NG_ATMLLC_HEADER, hdr->llchdr, 6);
 218                 if ((m->m_flags & M_HASFCS) != 0) {
 219                         ATM_LLC_SETTYPE(hdr, NG_ATMLLC_TYPE_ETHERNET_FCS);
 220                 } else {
 221                         ATM_LLC_SETTYPE(hdr, NG_ATMLLC_TYPE_ETHERNET_NOFCS);
 222                 }
 223                 outhook = priv->atm;
 224         } else if (hook == priv->fddi) {
 225                 /* Add the LLC header */
 226                 M_PREPEND(m, NG_ATMLLC_HEADER_LEN + 3, M_DONTWAIT);
 227                 if (m == NULL) {
 228                         printf("ng_atmllc: M_PREPEND failed\n");
 229                         NG_FREE_ITEM(item);
 230                         return (ENOMEM);
 231                 }
 232                 hdr = mtod(m, struct atmllc *);
 233                 bzero((void *)hdr, sizeof(struct atmllc) + 3);
 234                 bcopy(NG_ATMLLC_HEADER, hdr->llchdr, 6);
 235                 if ((m->m_flags & M_HASFCS) != 0) {
 236                         ATM_LLC_SETTYPE(hdr, NG_ATMLLC_TYPE_FDDI_FCS);
 237                 } else {
 238                         ATM_LLC_SETTYPE(hdr, NG_ATMLLC_TYPE_FDDI_NOFCS);
 239                 }
 240                 outhook = priv->atm;
 241         }
 242
 243         if (outhook == NULL) {
 244                 NG_FREE_ITEM(item);
 245                 return (0);
 246         }
 247
 248         NG_FWD_NEW_DATA(error, item, outhook, m);
 249         return (error);
 250 }
 251
 252 static int
 253 ng_atmllc_disconnect(hook_p hook)
 254 {
 255         node_p  node;
 256         struct  ng_atmllc_priv *priv;
 257
 258         node = NG_HOOK_NODE(hook);
 259         priv = NG_NODE_PRIVATE(node);
 260
 261         if (hook == priv->atm) {
 262                 priv->atm = NULL;
 263         } else if (hook == priv->ether) {
 264                 priv->ether = NULL;
 265         } else if (hook == priv->fddi) {
 266                 priv->fddi = NULL;
 267         }
 268
 269         if (NG_NODE_NUMHOOKS(node) == 0 && NG_NODE_IS_VALID(node)) {
 270                 ng_rmnode_self(node);
 271         }
 272
 273         return (0);
 274 }