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
  44 #define NG_ATMLLC_HEADER                "\252\252\3\0\200\302"
  45 #define NG_ATMLLC_HEADER_LEN            (sizeof(struct atmllc))
  46 #define NG_ATMLLC_TYPE_ETHERNET_FCS     0x0001
  47 #define NG_ATMLLC_TYPE_FDDI_FCS         0x0004
  48 #define NG_ATMLLC_TYPE_ETHERNET_NOFCS   0x0007
  49 #define NG_ATMLLC_TYPE_FDDI_NOFCS       0x000A
  50
  51 struct ng_atmllc_priv {
  52         hook_p          atm;
  53         hook_p          ether;
  54         hook_p          fddi;
  55 };
  56
  57 struct atmllc {
  58         uint8_t         llchdr[6];      /* aa.aa.03.00.00.00 */
  59         uint8_t         type[2];        /* "ethernet" type */
  60 };
  61
  62 /* ATM_LLC macros: note type code in host byte order */
  63 #define ATM_LLC_TYPE(X) (((X)->type[0] << 8) | ((X)->type[1]))
  64 #define ATM_LLC_SETTYPE(X, V) do {              \
  65         (X)->type[0] = ((V) >> 8) & 0xff;       \
  66         (X)->type[1] = ((V) & 0xff);            \
  67     } while (0)
  68
  69 /* Netgraph methods. */
  70 static ng_constructor_t         ng_atmllc_constructor;
  71 static ng_shutdown_t            ng_atmllc_shutdown;
  72 static ng_rcvmsg_t              ng_atmllc_rcvmsg;
  73 static ng_newhook_t             ng_atmllc_newhook;
  74 static ng_rcvdata_t             ng_atmllc_rcvdata;
  75 static ng_disconnect_t          ng_atmllc_disconnect;
  76
  77 static struct ng_type ng_atmllc_typestruct = {
  78         .version =      NG_ABI_VERSION,
  79         .name =         NG_ATMLLC_NODE_TYPE,
  80         .constructor =  ng_atmllc_constructor,
  81         .rcvmsg =       ng_atmllc_rcvmsg,
  82         .shutdown =     ng_atmllc_shutdown,
  83         .newhook =      ng_atmllc_newhook,
  84         .rcvdata =      ng_atmllc_rcvdata,
  85         .disconnect =   ng_atmllc_disconnect,
  86 };
  87 NETGRAPH_INIT(atmllc, &ng_atmllc_typestruct);
  88
  89 static int
  90 ng_atmllc_constructor(node_p node)
  91 {
  92         struct  ng_atmllc_priv *priv;
  93
  94         priv = malloc(sizeof(*priv), M_NETGRAPH, M_WAITOK | M_ZERO);
  95         NG_NODE_SET_PRIVATE(node, priv);
  96
  97         return (0);
  98 }
  99
 100 static int
 101 ng_atmllc_rcvmsg(node_p node, item_p item, hook_p lasthook)
 102 {
 103         struct  ng_mesg *msg;
 104         int     error;
 105
 106         error = 0;
 107         NGI_GET_MSG(item, msg);
 108         msg->header.flags |= NGF_RESP;
 109         NG_RESPOND_MSG(error, node, item, msg);
 110         return (error);
 111 }
 112
 113 static int
 114 ng_atmllc_shutdown(node_p node)
 115 {
 116         struct  ng_atmllc_priv *priv;
 117
 118         priv = NG_NODE_PRIVATE(node);
 119
 120         free(priv, M_NETGRAPH);
 121
 122         NG_NODE_UNREF(node);
 123
 124         return (0);
 125 }
 126
 127 static int
 128 ng_atmllc_newhook(node_p node, hook_p hook, const char *name)
 129 {
 130         struct  ng_atmllc_priv *priv;
 131
 132         priv = NG_NODE_PRIVATE(node);
 133
 134         if (strcmp(name, NG_ATMLLC_HOOK_ATM) == 0) {
 135                 if (priv->atm != NULL) {
 136                         return (EISCONN);
 137                 }
 138                 priv->atm = hook;
 139         } else if (strcmp(name, NG_ATMLLC_HOOK_ETHER) == 0) {
 140                 if (priv->ether != NULL) {
 141                         return (EISCONN);
 142                 }
 143                 priv->ether = hook;
 144         } else if (strcmp(name, NG_ATMLLC_HOOK_FDDI) == 0) {
 145                 if (priv->fddi != NULL) {
 146                         return (EISCONN);
 147                 }
 148                 priv->fddi = hook;
 149         } else {
 150                 return (EINVAL);
 151         }
 152
 153         return (0);
 154 }
 155
 156 static int
 157 ng_atmllc_rcvdata(hook_p hook, item_p item)
 158 {
 159         struct  ng_atmllc_priv *priv;
 160         struct  mbuf *m;
 161         struct  atmllc *hdr;
 162         hook_p  outhook;
 163         u_int   padding;
 164         int     error;
 165
 166         priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
 167         NGI_GET_M(item, m);
 168         outhook = NULL;
 169         padding = 0;
 170
 171         if (hook == priv->atm) {
 172                 /* Ditch the psuedoheader. */
 173                 hdr = mtod(m, struct atmllc *);
 174                 /* m_adj(m, sizeof(struct atm_pseudohdr)); */
 175
 176                 /*
 177                  * Make sure we have the LLC and ethernet headers.
 178                  * The ethernet header size is slightly larger than the FDDI
 179                  * header, which is convenient.
 180                  */
 181                 if (m->m_len < sizeof(struct atmllc) + ETHER_HDR_LEN) {
 182                         m = m_pullup(m, sizeof(struct atmllc) + ETHER_HDR_LEN);
 183                         if (m == NULL) {
 184                                 NG_FREE_ITEM(item);
 185                                 return (ENOMEM);
 186                         }
 187                 }
 188
 189                 /* Decode the LLC header. */
 190                 hdr = mtod(m, struct atmllc *);
 191                 if (ATM_LLC_TYPE(hdr) == NG_ATMLLC_TYPE_ETHERNET_NOFCS) {
 192                         m->m_flags &= ~M_HASFCS;
 193                         outhook = priv->ether;
 194                         padding = 2;
 195                 } else if (ATM_LLC_TYPE(hdr) == NG_ATMLLC_TYPE_ETHERNET_FCS) {
 196                         m->m_flags |= M_HASFCS;
 197                         outhook = priv->ether;
 198                         padding = 2;
 199                 } else if (ATM_LLC_TYPE(hdr) == NG_ATMLLC_TYPE_FDDI_NOFCS) {
 200                         m->m_flags &= ~M_HASFCS;
 201                         outhook = priv->fddi;
 202                         padding = 3;
 203                 } else if (ATM_LLC_TYPE(hdr) == NG_ATMLLC_TYPE_FDDI_FCS) {
 204                         m->m_flags |= M_HASFCS;
 205                         outhook = priv->fddi;
 206                         padding = 3;
 207                 } else {
 208                         printf("ng_atmllc: unknown type: %x\n",
 209                             ATM_LLC_TYPE(hdr));
 210                 }
 211
 212                 /* Remove the LLC header and any padding*/
 213                 m_adj(m, sizeof(struct atmllc) + padding);
 214         } else if (hook == priv->ether) {
 215                 /* Add the LLC header */
 216                 M_PREPEND(m, NG_ATMLLC_HEADER_LEN + 2, M_NOWAIT);
 217                 if (m == NULL) {
 218                         printf("ng_atmllc: M_PREPEND failed\n");
 219                         NG_FREE_ITEM(item);
 220                         return (ENOMEM);
 221                 }
 222                 hdr = mtod(m, struct atmllc *);
 223                 bzero((void *)hdr, sizeof(struct atmllc) + 2);
 224                 bcopy(NG_ATMLLC_HEADER, hdr->llchdr, 6);
 225                 if ((m->m_flags & M_HASFCS) != 0) {
 226                         ATM_LLC_SETTYPE(hdr, NG_ATMLLC_TYPE_ETHERNET_FCS);
 227                 } else {
 228                         ATM_LLC_SETTYPE(hdr, NG_ATMLLC_TYPE_ETHERNET_NOFCS);
 229                 }
 230                 outhook = priv->atm;
 231         } else if (hook == priv->fddi) {
 232                 /* Add the LLC header */
 233                 M_PREPEND(m, NG_ATMLLC_HEADER_LEN + 3, M_NOWAIT);
 234                 if (m == NULL) {
 235                         printf("ng_atmllc: M_PREPEND failed\n");
 236                         NG_FREE_ITEM(item);
 237                         return (ENOMEM);
 238                 }
 239                 hdr = mtod(m, struct atmllc *);
 240                 bzero((void *)hdr, sizeof(struct atmllc) + 3);
 241                 bcopy(NG_ATMLLC_HEADER, hdr->llchdr, 6);
 242                 if ((m->m_flags & M_HASFCS) != 0) {
 243                         ATM_LLC_SETTYPE(hdr, NG_ATMLLC_TYPE_FDDI_FCS);
 244                 } else {
 245                         ATM_LLC_SETTYPE(hdr, NG_ATMLLC_TYPE_FDDI_NOFCS);
 246                 }
 247                 outhook = priv->atm;
 248         }
 249
 250         if (outhook == NULL) {
 251                 NG_FREE_M(m);
 252                 NG_FREE_ITEM(item);
 253                 return (0);
 254         }
 255
 256         NG_FWD_NEW_DATA(error, item, outhook, m);
 257         return (error);
 258 }
 259
 260 static int
 261 ng_atmllc_disconnect(hook_p hook)
 262 {
 263         node_p  node;
 264         struct  ng_atmllc_priv *priv;
 265
 266         node = NG_HOOK_NODE(hook);
 267         priv = NG_NODE_PRIVATE(node);
 268
 269         if (hook == priv->atm) {
 270                 priv->atm = NULL;
 271         } else if (hook == priv->ether) {
 272                 priv->ether = NULL;
 273         } else if (hook == priv->fddi) {
 274                 priv->fddi = NULL;
 275         }
 276
 277         if (NG_NODE_NUMHOOKS(node) == 0 && NG_NODE_IS_VALID(node)) {
 278                 ng_rmnode_self(node);
 279         }
 280
 281         return (0);
 282 }