fddi.c revision 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2
1/* 2 * INET An implementation of the TCP/IP protocol suite for the LINUX 3 * operating system. INET is implemented using the BSD Socket 4 * interface as the means of communication with the user level. 5 * 6 * FDDI-type device handling. 7 * 8 * Version: @(#)fddi.c 1.0.0 08/12/96 9 * 10 * Authors: Lawrence V. Stefani, <stefani@lkg.dec.com> 11 * 12 * fddi.c is based on previous eth.c and tr.c work by 13 * Ross Biro, <bir7@leland.Stanford.Edu> 14 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> 15 * Mark Evans, <evansmp@uhura.aston.ac.uk> 16 * Florian La Roche, <rzsfl@rz.uni-sb.de> 17 * Alan Cox, <gw4pts@gw4pts.ampr.org> 18 * 19 * This program is free software; you can redistribute it and/or 20 * modify it under the terms of the GNU General Public License 21 * as published by the Free Software Foundation; either version 22 * 2 of the License, or (at your option) any later version. 23 * 24 * Changes 25 * Alan Cox : New arp/rebuild header 26 * Maciej W. Rozycki : IPv6 support 27 */ 28 29#include <linux/config.h> 30#include <linux/module.h> 31#include <asm/system.h> 32#include <linux/types.h> 33#include <linux/kernel.h> 34#include <linux/sched.h> 35#include <linux/string.h> 36#include <linux/mm.h> 37#include <linux/socket.h> 38#include <linux/in.h> 39#include <linux/inet.h> 40#include <linux/netdevice.h> 41#include <linux/fddidevice.h> 42#include <linux/if_ether.h> 43#include <linux/skbuff.h> 44#include <linux/errno.h> 45#include <net/arp.h> 46#include <net/sock.h> 47 48/* 49 * Create the FDDI MAC header for an arbitrary protocol layer 50 * 51 * saddr=NULL means use device source address 52 * daddr=NULL means leave destination address (eg unresolved arp) 53 */ 54 55static int fddi_header(struct sk_buff *skb, struct net_device *dev, 56 unsigned short type, 57 void *daddr, void *saddr, unsigned len) 58{ 59 int hl = FDDI_K_SNAP_HLEN; 60 struct fddihdr *fddi; 61 62 if(type != ETH_P_IP && type != ETH_P_IPV6 && type != ETH_P_ARP) 63 hl=FDDI_K_8022_HLEN-3; 64 fddi = (struct fddihdr *)skb_push(skb, hl); 65 fddi->fc = FDDI_FC_K_ASYNC_LLC_DEF; 66 if(type == ETH_P_IP || type == ETH_P_IPV6 || type == ETH_P_ARP) 67 { 68 fddi->hdr.llc_snap.dsap = FDDI_EXTENDED_SAP; 69 fddi->hdr.llc_snap.ssap = FDDI_EXTENDED_SAP; 70 fddi->hdr.llc_snap.ctrl = FDDI_UI_CMD; 71 fddi->hdr.llc_snap.oui[0] = 0x00; 72 fddi->hdr.llc_snap.oui[1] = 0x00; 73 fddi->hdr.llc_snap.oui[2] = 0x00; 74 fddi->hdr.llc_snap.ethertype = htons(type); 75 } 76 77 /* Set the source and destination hardware addresses */ 78 79 if (saddr != NULL) 80 memcpy(fddi->saddr, saddr, dev->addr_len); 81 else 82 memcpy(fddi->saddr, dev->dev_addr, dev->addr_len); 83 84 if (daddr != NULL) 85 { 86 memcpy(fddi->daddr, daddr, dev->addr_len); 87 return(hl); 88 } 89 90 return(-hl); 91} 92 93 94/* 95 * Rebuild the FDDI MAC header. This is called after an ARP 96 * (or in future other address resolution) has completed on 97 * this sk_buff. We now let ARP fill in the other fields. 98 */ 99 100static int fddi_rebuild_header(struct sk_buff *skb) 101{ 102 struct fddihdr *fddi = (struct fddihdr *)skb->data; 103 104#ifdef CONFIG_INET 105 if (fddi->hdr.llc_snap.ethertype == __constant_htons(ETH_P_IP)) 106 /* Try to get ARP to resolve the header and fill destination address */ 107 return arp_find(fddi->daddr, skb); 108 else 109#endif 110 { 111 printk("%s: Don't know how to resolve type %02X addresses.\n", 112 skb->dev->name, htons(fddi->hdr.llc_snap.ethertype)); 113 return(0); 114 } 115} 116 117 118/* 119 * Determine the packet's protocol ID and fill in skb fields. 120 * This routine is called before an incoming packet is passed 121 * up. It's used to fill in specific skb fields and to set 122 * the proper pointer to the start of packet data (skb->data). 123 */ 124 125unsigned short fddi_type_trans(struct sk_buff *skb, struct net_device *dev) 126{ 127 struct fddihdr *fddi = (struct fddihdr *)skb->data; 128 unsigned short type; 129 130 /* 131 * Set mac.raw field to point to FC byte, set data field to point 132 * to start of packet data. Assume 802.2 SNAP frames for now. 133 */ 134 135 skb->mac.raw = skb->data; /* point to frame control (FC) */ 136 137 if(fddi->hdr.llc_8022_1.dsap==0xe0) 138 { 139 skb_pull(skb, FDDI_K_8022_HLEN-3); 140 type = __constant_htons(ETH_P_802_2); 141 } 142 else 143 { 144 skb_pull(skb, FDDI_K_SNAP_HLEN); /* adjust for 21 byte header */ 145 type=fddi->hdr.llc_snap.ethertype; 146 } 147 148 /* Set packet type based on destination address and flag settings */ 149 150 if (*fddi->daddr & 0x01) 151 { 152 if (memcmp(fddi->daddr, dev->broadcast, FDDI_K_ALEN) == 0) 153 skb->pkt_type = PACKET_BROADCAST; 154 else 155 skb->pkt_type = PACKET_MULTICAST; 156 } 157 158 else if (dev->flags & IFF_PROMISC) 159 { 160 if (memcmp(fddi->daddr, dev->dev_addr, FDDI_K_ALEN)) 161 skb->pkt_type = PACKET_OTHERHOST; 162 } 163 164 /* Assume 802.2 SNAP frames, for now */ 165 166 return(type); 167} 168 169EXPORT_SYMBOL(fddi_type_trans); 170 171static int fddi_change_mtu(struct net_device *dev, int new_mtu) 172{ 173 if ((new_mtu < FDDI_K_SNAP_HLEN) || (new_mtu > FDDI_K_SNAP_DLEN)) 174 return(-EINVAL); 175 dev->mtu = new_mtu; 176 return(0); 177} 178 179static void fddi_setup(struct net_device *dev) 180{ 181 dev->change_mtu = fddi_change_mtu; 182 dev->hard_header = fddi_header; 183 dev->rebuild_header = fddi_rebuild_header; 184 185 dev->type = ARPHRD_FDDI; 186 dev->hard_header_len = FDDI_K_SNAP_HLEN+3; /* Assume 802.2 SNAP hdr len + 3 pad bytes */ 187 dev->mtu = FDDI_K_SNAP_DLEN; /* Assume max payload of 802.2 SNAP frame */ 188 dev->addr_len = FDDI_K_ALEN; 189 dev->tx_queue_len = 100; /* Long queues on FDDI */ 190 dev->flags = IFF_BROADCAST | IFF_MULTICAST; 191 192 memset(dev->broadcast, 0xFF, FDDI_K_ALEN); 193} 194 195/** 196 * alloc_fddidev - Register FDDI device 197 * @sizeof_priv: Size of additional driver-private structure to be allocated 198 * for this FDDI device 199 * 200 * Fill in the fields of the device structure with FDDI-generic values. 201 * 202 * Constructs a new net device, complete with a private data area of 203 * size @sizeof_priv. A 32-byte (not bit) alignment is enforced for 204 * this private data area. 205 */ 206struct net_device *alloc_fddidev(int sizeof_priv) 207{ 208 return alloc_netdev(sizeof_priv, "fddi%d", fddi_setup); 209} 210EXPORT_SYMBOL(alloc_fddidev); 211