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-rw-r--r--net/ethernet/eth.c308
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diff --git a/net/ethernet/eth.c b/net/ethernet/eth.c
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+/*
+ * 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>
+ * Florian La Roche, <rzsfl@rz.uni-sb.de>
+ * Alan Cox, <gw4pts@gw4pts.ampr.org>
+ *
+ * Fixes:
+ * Mr Linux : Arp problems
+ * Alan Cox : Generic queue tidyup (very tiny here)
+ * Alan Cox : eth_header ntohs should be htons
+ * Alan Cox : eth_rebuild_header missing an htons and
+ * minor other things.
+ * Tegge : Arp bug fixes.
+ * Florian : Removed many unnecessary functions, code cleanup
+ * and changes for new arp and skbuff.
+ * Alan Cox : Redid header building to reflect new format.
+ * Alan Cox : ARP only when compiled with CONFIG_INET
+ * Greg Page : 802.2 and SNAP stuff.
+ * Alan Cox : MAC layer pointers/new format.
+ * Paul Gortmaker : eth_copy_and_sum shouldn't csum padding.
+ * Alan Cox : Protect against forwarding explosions with
+ * older network drivers and IFF_ALLMULTI.
+ * Christer Weinigel : Better rebuild header message.
+ * Andrew Morton : 26Feb01: kill ether_setup() - use netdev_boot_setup().
+ *
+ * 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 <linux/module.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 <linux/inet.h>
+#include <linux/ip.h>
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/skbuff.h>
+#include <linux/errno.h>
+#include <linux/config.h>
+#include <linux/init.h>
+#include <net/dst.h>
+#include <net/arp.h>
+#include <net/sock.h>
+#include <net/ipv6.h>
+#include <net/ip.h>
+#include <asm/uaccess.h>
+#include <asm/system.h>
+#include <asm/checksum.h>
+
+extern int __init netdev_boot_setup(char *str);
+
+__setup("ether=", netdev_boot_setup);
+
+/*
+ * Create the Ethernet MAC header for an arbitrary protocol layer
+ *
+ * saddr=NULL means use device source address
+ * daddr=NULL means leave destination address (eg unresolved arp)
+ */
+
+int eth_header(struct sk_buff *skb, struct net_device *dev, unsigned short type,
+ void *daddr, void *saddr, unsigned len)
+{
+ struct ethhdr *eth = (struct ethhdr *)skb_push(skb,ETH_HLEN);
+
+ /*
+ * Set the protocol type. For a packet of type ETH_P_802_3 we put the length
+ * in here instead. It is up to the 802.2 layer to carry protocol information.
+ */
+
+ if(type!=ETH_P_802_3)
+ eth->h_proto = htons(type);
+ else
+ eth->h_proto = htons(len);
+
+ /*
+ * Set the source hardware address.
+ */
+
+ if(saddr)
+ memcpy(eth->h_source,saddr,dev->addr_len);
+ else
+ memcpy(eth->h_source,dev->dev_addr,dev->addr_len);
+
+ /*
+ * Anyway, the loopback-device should never use this function...
+ */
+
+ if (dev->flags & (IFF_LOOPBACK|IFF_NOARP))
+ {
+ memset(eth->h_dest, 0, dev->addr_len);
+ return ETH_HLEN;
+ }
+
+ if(daddr)
+ {
+ memcpy(eth->h_dest,daddr,dev->addr_len);
+ return ETH_HLEN;
+ }
+
+ return -ETH_HLEN;
+}
+
+
+/*
+ * Rebuild the Ethernet MAC header. This is called after an ARP
+ * (or in future other address resolution) has completed on this
+ * sk_buff. We now let ARP fill in the other fields.
+ *
+ * This routine CANNOT use cached dst->neigh!
+ * Really, it is used only when dst->neigh is wrong.
+ */
+
+int eth_rebuild_header(struct sk_buff *skb)
+{
+ struct ethhdr *eth = (struct ethhdr *)skb->data;
+ struct net_device *dev = skb->dev;
+
+ switch (eth->h_proto)
+ {
+#ifdef CONFIG_INET
+ case __constant_htons(ETH_P_IP):
+ return arp_find(eth->h_dest, skb);
+#endif
+ default:
+ printk(KERN_DEBUG
+ "%s: unable to resolve type %X addresses.\n",
+ dev->name, (int)eth->h_proto);
+
+ memcpy(eth->h_source, dev->dev_addr, dev->addr_len);
+ break;
+ }
+
+ return 0;
+}
+
+
+/*
+ * Determine the packet's protocol ID. The rule here is that we
+ * assume 802.3 if the type field is short enough to be a length.
+ * This is normal practice and works for any 'now in use' protocol.
+ */
+
+unsigned short eth_type_trans(struct sk_buff *skb, struct net_device *dev)
+{
+ struct ethhdr *eth;
+ unsigned char *rawp;
+
+ skb->mac.raw=skb->data;
+ skb_pull(skb,ETH_HLEN);
+ eth = eth_hdr(skb);
+ skb->input_dev = dev;
+
+ if(*eth->h_dest&1)
+ {
+ if(memcmp(eth->h_dest,dev->broadcast, ETH_ALEN)==0)
+ skb->pkt_type=PACKET_BROADCAST;
+ else
+ skb->pkt_type=PACKET_MULTICAST;
+ }
+
+ /*
+ * This ALLMULTI check should be redundant by 1.4
+ * so don't forget to remove it.
+ *
+ * Seems, you forgot to remove it. All silly devices
+ * seems to set IFF_PROMISC.
+ */
+
+ else if(1 /*dev->flags&IFF_PROMISC*/)
+ {
+ if(memcmp(eth->h_dest,dev->dev_addr, ETH_ALEN))
+ skb->pkt_type=PACKET_OTHERHOST;
+ }
+
+ if (ntohs(eth->h_proto) >= 1536)
+ return eth->h_proto;
+
+ rawp = skb->data;
+
+ /*
+ * This is a magic hack to spot IPX packets. Older Novell breaks
+ * the protocol design and runs IPX over 802.3 without an 802.2 LLC
+ * layer. We look for FFFF which isn't a used 802.2 SSAP/DSAP. This
+ * won't work for fault tolerant netware but does for the rest.
+ */
+ if (*(unsigned short *)rawp == 0xFFFF)
+ return htons(ETH_P_802_3);
+
+ /*
+ * Real 802.2 LLC
+ */
+ return htons(ETH_P_802_2);
+}
+
+static int eth_header_parse(struct sk_buff *skb, unsigned char *haddr)
+{
+ struct ethhdr *eth = eth_hdr(skb);
+ memcpy(haddr, eth->h_source, ETH_ALEN);
+ return ETH_ALEN;
+}
+
+int eth_header_cache(struct neighbour *neigh, struct hh_cache *hh)
+{
+ unsigned short type = hh->hh_type;
+ struct ethhdr *eth;
+ struct net_device *dev = neigh->dev;
+
+ eth = (struct ethhdr*)
+ (((u8*)hh->hh_data) + (HH_DATA_OFF(sizeof(*eth))));
+
+ if (type == __constant_htons(ETH_P_802_3))
+ return -1;
+
+ eth->h_proto = type;
+ memcpy(eth->h_source, dev->dev_addr, dev->addr_len);
+ memcpy(eth->h_dest, neigh->ha, dev->addr_len);
+ hh->hh_len = ETH_HLEN;
+ return 0;
+}
+
+/*
+ * Called by Address Resolution module to notify changes in address.
+ */
+
+void eth_header_cache_update(struct hh_cache *hh, struct net_device *dev, unsigned char * haddr)
+{
+ memcpy(((u8*)hh->hh_data) + HH_DATA_OFF(sizeof(struct ethhdr)),
+ haddr, dev->addr_len);
+}
+
+EXPORT_SYMBOL(eth_type_trans);
+
+static int eth_mac_addr(struct net_device *dev, void *p)
+{
+ struct sockaddr *addr=p;
+ if (netif_running(dev))
+ return -EBUSY;
+ memcpy(dev->dev_addr, addr->sa_data,dev->addr_len);
+ return 0;
+}
+
+static int eth_change_mtu(struct net_device *dev, int new_mtu)
+{
+ if ((new_mtu < 68) || (new_mtu > 1500))
+ return -EINVAL;
+ dev->mtu = new_mtu;
+ return 0;
+}
+
+/*
+ * Fill in the fields of the device structure with ethernet-generic values.
+ */
+void ether_setup(struct net_device *dev)
+{
+ dev->change_mtu = eth_change_mtu;
+ dev->hard_header = eth_header;
+ dev->rebuild_header = eth_rebuild_header;
+ dev->set_mac_address = eth_mac_addr;
+ dev->hard_header_cache = eth_header_cache;
+ dev->header_cache_update= eth_header_cache_update;
+ dev->hard_header_parse = eth_header_parse;
+
+ dev->type = ARPHRD_ETHER;
+ dev->hard_header_len = ETH_HLEN;
+ dev->mtu = 1500; /* eth_mtu */
+ dev->addr_len = ETH_ALEN;
+ dev->tx_queue_len = 1000; /* Ethernet wants good queues */
+ dev->flags = IFF_BROADCAST|IFF_MULTICAST;
+
+ memset(dev->broadcast,0xFF, ETH_ALEN);
+
+}
+EXPORT_SYMBOL(ether_setup);
+
+/**
+ * alloc_etherdev - Allocates and sets up an ethernet device
+ * @sizeof_priv: Size of additional driver-private structure to be allocated
+ * for this ethernet device
+ *
+ * Fill in the fields of the device structure with ethernet-generic
+ * values. Basically does everything except registering the device.
+ *
+ * Constructs a new net device, complete with a private data area of
+ * size @sizeof_priv. A 32-byte (not bit) alignment is enforced for
+ * this private data area.
+ */
+
+struct net_device *alloc_etherdev(int sizeof_priv)
+{
+ return alloc_netdev(sizeof_priv, "eth%d", ether_setup);
+}
+EXPORT_SYMBOL(alloc_etherdev);