sys/netgraph/ng_atmllc.c

   1 /*-
   2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
   3  *
   4  * Copyright (c) 2003-2004 Benno Rice <benno@eloquent.com.au>
   5  * All Rights Reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR  ``AS IS'' AND
  17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR  BE LIABLE
  20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  26  * SUCH DAMAGE.
  27  *
  28  * $FreeBSD$
  29  */
  30
  31 #include <sys/param.h>
  32 #include <sys/systm.h>
  33 #include <sys/kernel.h>
  34 #include <sys/malloc.h>
  35 #include <sys/mbuf.h>
  36 #include <sys/socket.h>
  37 #include <sys/sockio.h>
  38
  39 #include <netgraph/ng_message.h>
  40 #include <netgraph/netgraph.h>
  41 #include <netgraph/ng_atmllc.h>
  42
  43 #include <net/if.h>
  44 #include <net/ethernet.h>       /* for M_HASFCS and ETHER_HDR_LEN */
  45
  46 #define NG_ATMLLC_HEADER                "\252\252\3\0\200\302"
  47 #define NG_ATMLLC_HEADER_LEN            (sizeof(struct atmllc))
  48 #define NG_ATMLLC_TYPE_ETHERNET_FCS     0x0001
  49 #define NG_ATMLLC_TYPE_FDDI_FCS         0x0004
  50 #define NG_ATMLLC_TYPE_ETHERNET_NOFCS   0x0007
  51 #define NG_ATMLLC_TYPE_FDDI_NOFCS       0x000A
  52
  53 struct ng_atmllc_priv {
  54         hook_p          atm;
  55         hook_p          ether;
  56         hook_p          fddi;
  57 };
  58
  59 struct atmllc {
  60         uint8_t         llchdr[6];      /* aa.aa.03.00.00.00 */
  61         uint8_t         type[2];        /* "ethernet" type */
  62 };
  63
  64 /* ATM_LLC macros: note type code in host byte order */
  65 #define ATM_LLC_TYPE(X) (((X)->type[0] << 8) | ((X)->type[1]))
  66 #define ATM_LLC_SETTYPE(X, V) do {              \
  67         (X)->type[0] = ((V) >> 8) & 0xff;       \
  68         (X)->type[1] = ((V) & 0xff);            \
  69     } while (0)
  70
  71 /* Netgraph methods. */
  72 static ng_constructor_t         ng_atmllc_constructor;
  73 static ng_shutdown_t            ng_atmllc_shutdown;
  74 static ng_rcvmsg_t              ng_atmllc_rcvmsg;
  75 static ng_newhook_t             ng_atmllc_newhook;
  76 static ng_rcvdata_t             ng_atmllc_rcvdata;
  77 static ng_disconnect_t          ng_atmllc_disconnect;
  78
  79 static struct ng_type ng_atmllc_typestruct = {
  80         .version =      NG_ABI_VERSION,
  81         .name =         NG_ATMLLC_NODE_TYPE,
  82         .constructor =  ng_atmllc_constructor,
  83         .rcvmsg =       ng_atmllc_rcvmsg,
  84         .shutdown =     ng_atmllc_shutdown,
  85         .newhook =      ng_atmllc_newhook,
  86         .rcvdata =      ng_atmllc_rcvdata,
  87         .disconnect =   ng_atmllc_disconnect,
  88 };
  89 NETGRAPH_INIT(atmllc, &ng_atmllc_typestruct);
  90
  91 static int
  92 ng_atmllc_constructor(node_p node)
  93 {
  94         struct  ng_atmllc_priv *priv;
  95
  96         priv = malloc(sizeof(*priv), M_NETGRAPH, M_WAITOK | M_ZERO);
  97         NG_NODE_SET_PRIVATE(node, priv);
  98
  99         return (0);
 100 }
 101
 102 static int
 103 ng_atmllc_rcvmsg(node_p node, item_p item, hook_p lasthook)
 104 {
 105         struct  ng_mesg *msg;
 106         int     error;
 107
 108         error = 0;
 109         NGI_GET_MSG(item, msg);
 110         msg->header.flags |= NGF_RESP;
 111         NG_RESPOND_MSG(error, node, item, msg);
 112         return (error);
 113 }
 114
 115 static int
 116 ng_atmllc_shutdown(node_p node)
 117 {
 118         struct  ng_atmllc_priv *priv;
 119
 120         priv = NG_NODE_PRIVATE(node);
 121
 122         free(priv, M_NETGRAPH);
 123
 124         NG_NODE_UNREF(node);
 125
 126         return (0);
 127 }
 128
 129 static int
 130 ng_atmllc_newhook(node_p node, hook_p hook, const char *name)
 131 {
 132         struct  ng_atmllc_priv *priv;
 133
 134         priv = NG_NODE_PRIVATE(node);
 135
 136         if (strcmp(name, NG_ATMLLC_HOOK_ATM) == 0) {
 137                 if (priv->atm != NULL) {
 138                         return (EISCONN);
 139                 }
 140                 priv->atm = hook;
 141         } else if (strcmp(name, NG_ATMLLC_HOOK_ETHER) == 0) {
 142                 if (priv->ether != NULL) {
 143                         return (EISCONN);
 144                 }
 145                 priv->ether = hook;
 146         } else if (strcmp(name, NG_ATMLLC_HOOK_FDDI) == 0) {
 147                 if (priv->fddi != NULL) {
 148                         return (EISCONN);
 149                 }
 150                 priv->fddi = hook;
 151         } else {
 152                 return (EINVAL);
 153         }
 154
 155         return (0);
 156 }
 157
 158 static int
 159 ng_atmllc_rcvdata(hook_p hook, item_p item)
 160 {
 161         struct  ng_atmllc_priv *priv;
 162         struct  mbuf *m;
 163         struct  atmllc *hdr;
 164         hook_p  outhook;
 165         u_int   padding;
 166         int     error;
 167
 168         priv = NG_NODE_PRIVATE(NG_HOOK_NODE(hook));
 169         NGI_GET_M(item, m);
 170         outhook = NULL;
 171         padding = 0;
 172
 173         if (hook == priv->atm) {
 174                 /* Ditch the pseudoheader. */
 175                 hdr = mtod(m, struct atmllc *);
 176                 /* m_adj(m, sizeof(struct atm_pseudohdr)); */
 177
 178                 /*
 179                  * Make sure we have the LLC and ethernet headers.
 180                  * The ethernet header size is slightly larger than the FDDI
 181                  * header, which is convenient.
 182                  */
 183                 if (m->m_len < sizeof(struct atmllc) + ETHER_HDR_LEN) {
 184                         m = m_pullup(m, sizeof(struct atmllc) + ETHER_HDR_LEN);
 185                         if (m == NULL) {
 186                                 NG_FREE_ITEM(item);
 187                                 return (ENOMEM);
 188                         }
 189                 }
 190
 191                 /* Decode the LLC header. */
 192                 hdr = mtod(m, struct atmllc *);
 193                 if (ATM_LLC_TYPE(hdr) == NG_ATMLLC_TYPE_ETHERNET_NOFCS) {
 194                         m->m_flags &= ~M_HASFCS;
 195                         outhook = priv->ether;
 196                         padding = 2;
 197                 } else if (ATM_LLC_TYPE(hdr) == NG_ATMLLC_TYPE_ETHERNET_FCS) {
 198                         m->m_flags |= M_HASFCS;
 199                         outhook = priv->ether;
 200                         padding = 2;
 201                 } else if (ATM_LLC_TYPE(hdr) == NG_ATMLLC_TYPE_FDDI_NOFCS) {
 202                         m->m_flags &= ~M_HASFCS;
 203                         outhook = priv->fddi;
 204                         padding = 3;
 205                 } else if (ATM_LLC_TYPE(hdr) == NG_ATMLLC_TYPE_FDDI_FCS) {
 206                         m->m_flags |= M_HASFCS;
 207                         outhook = priv->fddi;
 208                         padding = 3;
 209                 } else {
 210                         printf("ng_atmllc: unknown type: %x\n",
 211                             ATM_LLC_TYPE(hdr));
 212                 }
 213
 214                 /* Remove the LLC header and any padding*/
 215                 m_adj(m, sizeof(struct atmllc) + padding);
 216         } else if (hook == priv->ether) {
 217                 /* Add the LLC header */
 218                 M_PREPEND(m, NG_ATMLLC_HEADER_LEN + 2, M_NOWAIT);
 219                 if (m == NULL) {
 220                         printf("ng_atmllc: M_PREPEND failed\n");
 221                         NG_FREE_ITEM(item);
 222                         return (ENOMEM);
 223                 }
 224                 hdr = mtod(m, struct atmllc *);
 225                 bzero((void *)hdr, sizeof(struct atmllc) + 2);
 226                 bcopy(NG_ATMLLC_HEADER, hdr->llchdr, 6);
 227                 if ((m->m_flags & M_HASFCS) != 0) {
 228                         ATM_LLC_SETTYPE(hdr, NG_ATMLLC_TYPE_ETHERNET_FCS);
 229                 } else {
 230                         ATM_LLC_SETTYPE(hdr, NG_ATMLLC_TYPE_ETHERNET_NOFCS);
 231                 }
 232                 outhook = priv->atm;
 233         } else if (hook == priv->fddi) {
 234                 /* Add the LLC header */
 235                 M_PREPEND(m, NG_ATMLLC_HEADER_LEN + 3, M_NOWAIT);
 236                 if (m == NULL) {
 237                         printf("ng_atmllc: M_PREPEND failed\n");
 238                         NG_FREE_ITEM(item);
 239                         return (ENOMEM);
 240                 }
 241                 hdr = mtod(m, struct atmllc *);
 242                 bzero((void *)hdr, sizeof(struct atmllc) + 3);
 243                 bcopy(NG_ATMLLC_HEADER, hdr->llchdr, 6);
 244                 if ((m->m_flags & M_HASFCS) != 0) {
 245                         ATM_LLC_SETTYPE(hdr, NG_ATMLLC_TYPE_FDDI_FCS);
 246                 } else {
 247                         ATM_LLC_SETTYPE(hdr, NG_ATMLLC_TYPE_FDDI_NOFCS);
 248                 }
 249                 outhook = priv->atm;
 250         }
 251
 252         if (outhook == NULL) {
 253                 NG_FREE_M(m);
 254                 NG_FREE_ITEM(item);
 255                 return (0);
 256         }
 257
 258         NG_FWD_NEW_DATA(error, item, outhook, m);
 259         return (error);
 260 }
 261
 262 static int
 263 ng_atmllc_disconnect(hook_p hook)
 264 {
 265         node_p  node;
 266         struct  ng_atmllc_priv *priv;
 267
 268         node = NG_HOOK_NODE(hook);
 269         priv = NG_NODE_PRIVATE(node);
 270
 271         if (hook == priv->atm) {
 272                 priv->atm = NULL;
 273         } else if (hook == priv->ether) {
 274                 priv->ether = NULL;
 275         } else if (hook == priv->fddi) {
 276                 priv->fddi = NULL;
 277         }
 278
 279         if (NG_NODE_NUMHOOKS(node) == 0 && NG_NODE_IS_VALID(node)) {
 280                 ng_rmnode_self(node);
 281         }
 282
 283         return (0);
 284 }