| /* |
| * INET An implementation of the TCP/IP protocol suite for the LINUX |
| * operating system. INET is implemented using the BSD Socket |
| * interface as the means of communication with the user level. |
| * |
| * Ethernet-type device handling. |
| * |
| * Version: @(#)eth.c 1.0.7 05/25/93 |
| * |
| * Authors: Ross Biro, <bir7@leland.Stanford.Edu> |
| * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG> |
| * Mark Evans, <evansmp@uhura.aston.ac.uk> |
| * |
| * This program is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU General Public License |
| * as published by the Free Software Foundation; either version |
| * 2 of the License, or (at your option) any later version. |
| */ |
| #include <asm/segment.h> |
| #include <asm/system.h> |
| #include <linux/types.h> |
| #include <linux/kernel.h> |
| #include <linux/sched.h> |
| #include <linux/string.h> |
| #include <linux/mm.h> |
| #include <linux/socket.h> |
| #include <linux/in.h> |
| #include "inet.h" |
| #include "dev.h" |
| #include "eth.h" |
| #include "timer.h" |
| #include "ip.h" |
| #include "route.h" |
| #include "protocol.h" |
| #include "tcp.h" |
| #include "skbuff.h" |
| #include "sock.h" |
| #include <linux/errno.h> |
| #include "arp.h" |
| |
| |
| /* Display an Ethernet address in readable format. */ |
| char *eth_print(unsigned char *ptr) |
| { |
| static char buff[64]; |
| |
| if (ptr == NULL) return("[NONE]"); |
| sprintf(buff, "%02X:%02X:%02X:%02X:%02X:%02X", |
| (ptr[0] & 255), (ptr[1] & 255), (ptr[2] & 255), |
| (ptr[3] & 255), (ptr[4] & 255), (ptr[5] & 255) |
| ); |
| return(buff); |
| } |
| |
| |
| /* Display the contents of the Ethernet MAC header. */ |
| void |
| eth_dump(struct ethhdr *eth) |
| { |
| if (inet_debug != DBG_ETH) return; |
| |
| printk("eth: SRC = %s ", eth_print(eth->h_source)); |
| printk("DST = %s ", eth_print(eth->h_dest)); |
| printk("TYPE = %04X\n", ntohs(eth->h_proto)); |
| } |
| |
| |
| /* Create the Ethernet MAC header. */ |
| int |
| eth_header(unsigned char *buff, struct device *dev, unsigned short type, |
| unsigned long daddr, unsigned long saddr, unsigned len) |
| { |
| struct ethhdr *eth; |
| |
| DPRINTF((DBG_DEV, "ETH: header(%s, ", in_ntoa(saddr))); |
| DPRINTF((DBG_DEV, "%s, 0x%X)\n", in_ntoa(daddr), type)); |
| |
| /* Fill in the basic Ethernet MAC header. */ |
| eth = (struct ethhdr *) buff; |
| eth->h_proto = ntohs(type); |
| memcpy(eth->h_source, dev->dev_addr, dev->addr_len); |
| |
| /* We don't ARP for the LOOPBACK device... */ |
| if (dev->flags & IFF_LOOPBACK) { |
| DPRINTF((DBG_DEV, "ETH: No header for loopback\n")); |
| memset(eth->h_dest, 0, dev->addr_len); |
| return(dev->hard_header_len); |
| } |
| |
| /* Check if we can use the MAC BROADCAST address. */ |
| if (chk_addr(daddr) == IS_BROADCAST) { |
| DPRINTF((DBG_DEV, "ETH: Using MAC Broadcast\n")); |
| memcpy(eth->h_dest, dev->broadcast, dev->addr_len); |
| return(dev->hard_header_len); |
| } |
| |
| /* No. Ask ARP to resolve the Ethernet address. */ |
| if (arp_find(eth->h_dest, daddr, dev, saddr)) { |
| return(-dev->hard_header_len); |
| } else return(dev->hard_header_len); |
| } |
| |
| |
| /* Rebuild the Ethernet MAC header. */ |
| int |
| eth_rebuild_header(void *buff, struct device *dev) |
| { |
| struct ethhdr *eth; |
| unsigned long src, dst; |
| |
| DPRINTF((DBG_DEV, "ETH: Using MAC Broadcast\n")); |
| eth = buff; |
| src = *(unsigned long *) eth->h_source; |
| dst = *(unsigned long *) eth->h_dest; |
| DPRINTF((DBG_DEV, "ETH: RebuildHeader: SRC=%s ", in_ntoa(src))); |
| DPRINTF((DBG_DEV, "DST=%s\n", in_ntoa(dst))); |
| if (arp_find(eth->h_dest, dst, dev, src)) return(1); |
| memcpy(eth->h_source, dev->dev_addr, dev->addr_len); |
| return(0); |
| } |
| |
| |
| /* Add an ARP entry for a host on this interface. */ |
| void |
| eth_add_arp(unsigned long addr, struct sk_buff *skb, struct device *dev) |
| { |
| struct ethhdr *eth; |
| |
| eth = (struct ethhdr *) (skb + 1); |
| arp_add(addr, eth->h_source, dev); |
| } |
| |
| |
| /* Determine the packet's protocol ID. */ |
| unsigned short |
| eth_type_trans(struct sk_buff *skb, struct device *dev) |
| { |
| struct ethhdr *eth; |
| |
| eth = (struct ethhdr *) (skb + 1); |
| return(eth->h_proto); |
| } |