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 * HIPPI-type device handling. 7 * 8 * Version: @(#)hippi.c 1.0.0 05/29/97 9 * 10 * Authors: Ross Biro 11 * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> 12 * Mark Evans, <evansmp@uhura.aston.ac.uk> 13 * Florian La Roche, <rzsfl@rz.uni-sb.de> 14 * Alan Cox, <gw4pts@gw4pts.ampr.org> 15 * Jes Sorensen, <Jes.Sorensen@cern.ch> 16 * 17 * This program is free software; you can redistribute it and/or 18 * modify it under the terms of the GNU General Public License 19 * as published by the Free Software Foundation; either version 20 * 2 of the License, or (at your option) any later version. 21 */ 22 23#include <linux/module.h> 24#include <linux/types.h> 25#include <linux/kernel.h> 26#include <linux/string.h> 27#include <linux/mm.h> 28#include <linux/socket.h> 29#include <linux/in.h> 30#include <linux/inet.h> 31#include <linux/netdevice.h> 32#include <linux/hippidevice.h> 33#include <linux/skbuff.h> 34#include <linux/errno.h> 35#include <net/arp.h> 36#include <net/sock.h> 37#include <asm/uaccess.h> 38 39/* 40 * Create the HIPPI MAC header for an arbitrary protocol layer 41 * 42 * saddr=NULL means use device source address 43 * daddr=NULL means leave destination address (eg unresolved arp) 44 */ 45 46static int hippi_header(struct sk_buff *skb, struct net_device *dev, 47 unsigned short type, 48 const void *daddr, const void *saddr, unsigned int len) 49{ 50 struct hippi_hdr *hip = (struct hippi_hdr *)skb_push(skb, HIPPI_HLEN); 51 struct hippi_cb *hcb = (struct hippi_cb *) skb->cb; 52 53 if (!len){ 54 len = skb->len - HIPPI_HLEN; 55 printk("hippi_header(): length not supplied\n"); 56 } 57 58 /* 59 * Due to the stupidity of the little endian byte-order we 60 * have to set the fp field this way. 61 */ 62 hip->fp.fixed = htonl(0x04800018); 63 hip->fp.d2_size = htonl(len + 8); 64 hip->le.fc = 0; 65 hip->le.double_wide = 0; /* only HIPPI 800 for the time being */ 66 hip->le.message_type = 0; /* Data PDU */ 67 68 hip->le.dest_addr_type = 2; /* 12 bit SC address */ 69 hip->le.src_addr_type = 2; /* 12 bit SC address */ 70 71 memcpy(hip->le.src_switch_addr, dev->dev_addr + 3, 3); 72 memset(&hip->le.reserved, 0, 16); 73 74 hip->snap.dsap = HIPPI_EXTENDED_SAP; 75 hip->snap.ssap = HIPPI_EXTENDED_SAP; 76 hip->snap.ctrl = HIPPI_UI_CMD; 77 hip->snap.oui[0] = 0x00; 78 hip->snap.oui[1] = 0x00; 79 hip->snap.oui[2] = 0x00; 80 hip->snap.ethertype = htons(type); 81 82 if (daddr) 83 { 84 memcpy(hip->le.dest_switch_addr, daddr + 3, 3); 85 memcpy(&hcb->ifield, daddr + 2, 4); 86 return HIPPI_HLEN; 87 } 88 hcb->ifield = 0; 89 return -((int)HIPPI_HLEN); 90} 91 92 93/* 94 * Rebuild the HIPPI MAC header. This is called after an ARP has 95 * completed on this sk_buff. We now let ARP fill in the other fields. 96 */ 97 98static int hippi_rebuild_header(struct sk_buff *skb) 99{ 100 struct hippi_hdr *hip = (struct hippi_hdr *)skb->data; 101 102 /* 103 * Only IP is currently supported 104 */ 105 106 if(hip->snap.ethertype != htons(ETH_P_IP)) 107 { 108 printk(KERN_DEBUG "%s: unable to resolve type %X addresses.\n",skb->dev->name,ntohs(hip->snap.ethertype)); 109 return 0; 110 } 111 112 /* 113 * We don't support dynamic ARP on HIPPI, but we use the ARP 114 * static ARP tables to hold the I-FIELDs. 115 */ 116 return arp_find(hip->le.daddr, skb); 117} 118 119 120/* 121 * Determine the packet's protocol ID. 122 */ 123 124__be16 hippi_type_trans(struct sk_buff *skb, struct net_device *dev) 125{ 126 struct hippi_hdr *hip; 127 128 /* 129 * This is actually wrong ... question is if we really should 130 * set the raw address here. 131 */ 132 skb->dev = dev; 133 skb_reset_mac_header(skb); 134 hip = (struct hippi_hdr *)skb_mac_header(skb); 135 skb_pull(skb, HIPPI_HLEN); 136 137 /* 138 * No fancy promisc stuff here now. 139 */ 140 141 return hip->snap.ethertype; 142} 143 144EXPORT_SYMBOL(hippi_type_trans); 145 146int hippi_change_mtu(struct net_device *dev, int new_mtu) 147{ 148 /* 149 * HIPPI's got these nice large MTUs. 150 */ 151 if ((new_mtu < 68) || (new_mtu > 65280)) 152 return -EINVAL; 153 dev->mtu = new_mtu; 154 return 0; 155} 156EXPORT_SYMBOL(hippi_change_mtu); 157 158/* 159 * For HIPPI we will actually use the lower 4 bytes of the hardware 160 * address as the I-FIELD rather than the actual hardware address. 161 */ 162int hippi_mac_addr(struct net_device *dev, void *p) 163{ 164 struct sockaddr *addr = p; 165 if (netif_running(dev)) 166 return -EBUSY; 167 memcpy(dev->dev_addr, addr->sa_data, dev->addr_len); 168 return 0; 169} 170EXPORT_SYMBOL(hippi_mac_addr); 171 172int hippi_neigh_setup_dev(struct net_device *dev, struct neigh_parms *p) 173{ 174 /* Never send broadcast/multicast ARP messages */ 175 p->mcast_probes = 0; 176 177 /* In IPv6 unicast probes are valid even on NBMA, 178 * because they are encapsulated in normal IPv6 protocol. 179 * Should be a generic flag. 180 */ 181 if (p->tbl->family != AF_INET6) 182 p->ucast_probes = 0; 183 return 0; 184} 185EXPORT_SYMBOL(hippi_neigh_setup_dev); 186 187static const struct header_ops hippi_header_ops = { 188 .create = hippi_header, 189 .rebuild = hippi_rebuild_header, 190}; 191 192 193static void hippi_setup(struct net_device *dev) 194{ 195 dev->header_ops = &hippi_header_ops; 196 197 /* 198 * We don't support HIPPI `ARP' for the time being, and probably 199 * never will unless someone else implements it. However we 200 * still need a fake ARPHRD to make ifconfig and friends play ball. 201 */ 202 dev->type = ARPHRD_HIPPI; 203 dev->hard_header_len = HIPPI_HLEN; 204 dev->mtu = 65280; 205 dev->addr_len = HIPPI_ALEN; 206 dev->tx_queue_len = 25 /* 5 */; 207 memset(dev->broadcast, 0xFF, HIPPI_ALEN); 208 209 210 /* 211 * HIPPI doesn't support broadcast+multicast and we only use 212 * static ARP tables. ARP is disabled by hippi_neigh_setup_dev. 213 */ 214 dev->flags = 0; 215} 216 217/** 218 * alloc_hippi_dev - Register HIPPI device 219 * @sizeof_priv: Size of additional driver-private structure to be allocated 220 * for this HIPPI device 221 * 222 * Fill in the fields of the device structure with HIPPI-generic values. 223 * 224 * Constructs a new net device, complete with a private data area of 225 * size @sizeof_priv. A 32-byte (not bit) alignment is enforced for 226 * this private data area. 227 */ 228 229struct net_device *alloc_hippi_dev(int sizeof_priv) 230{ 231 return alloc_netdev(sizeof_priv, "hip%d", hippi_setup); 232} 233 234EXPORT_SYMBOL(alloc_hippi_dev); 235