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-rw-r--r--net/ethernet/eth.c396
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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
+ * 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/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/init.h>
+#include <linux/if_ether.h>
+#include <net/dst.h>
+#include <net/arp.h>
+#include <net/sock.h>
+#include <net/ipv6.h>
+#include <net/ip.h>
+#include <net/dsa.h>
+#include <asm/uaccess.h>
+
+__setup("ether=", netdev_boot_setup);
+
+/**
+ * eth_header - create the Ethernet header
+ * @skb: buffer to alter
+ * @dev: source device
+ * @type: Ethernet type field
+ * @daddr: destination address (NULL leave destination address)
+ * @saddr: source address (NULL use device source address)
+ * @len: packet length (<= skb->len)
+ *
+ *
+ * Set the protocol type. For a packet of type ETH_P_802_3/2 we put the length
+ * in here instead.
+ */
+int eth_header(struct sk_buff *skb, struct net_device *dev,
+ unsigned short type,
+ const void *daddr, const void *saddr, unsigned len)
+{
+ struct ethhdr *eth = (struct ethhdr *)skb_push(skb, ETH_HLEN);
+
+ if (type != ETH_P_802_3 && type != ETH_P_802_2)
+ eth->h_proto = htons(type);
+ else
+ eth->h_proto = htons(len);
+
+ /*
+ * Set the source hardware address.
+ */
+
+ if (!saddr)
+ saddr = dev->dev_addr;
+ memcpy(eth->h_source, saddr, ETH_ALEN);
+
+ if (daddr) {
+ memcpy(eth->h_dest, daddr, ETH_ALEN);
+ return ETH_HLEN;
+ }
+
+ /*
+ * Anyway, the loopback-device should never use this function...
+ */
+
+ if (dev->flags & (IFF_LOOPBACK | IFF_NOARP)) {
+ memset(eth->h_dest, 0, ETH_ALEN);
+ return ETH_HLEN;
+ }
+
+ return -ETH_HLEN;
+}
+EXPORT_SYMBOL(eth_header);
+
+/**
+ * eth_rebuild_header- rebuild the Ethernet MAC header.
+ * @skb: socket buffer to update
+ *
+ * This is called after an ARP or IPV6 ndisc it's resolution on this
+ * sk_buff. We now let protocol (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 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, ntohs(eth->h_proto));
+
+ memcpy(eth->h_source, dev->dev_addr, ETH_ALEN);
+ break;
+ }
+
+ return 0;
+}
+EXPORT_SYMBOL(eth_rebuild_header);
+
+/**
+ * eth_type_trans - determine the packet's protocol ID.
+ * @skb: received socket data
+ * @dev: receiving network device
+ *
+ * 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.
+ */
+__be16 eth_type_trans(struct sk_buff *skb, struct net_device *dev)
+{
+ struct ethhdr *eth;
+
+ skb->dev = dev;
+ skb_reset_mac_header(skb);
+ skb_pull_inline(skb, ETH_HLEN);
+ eth = eth_hdr(skb);
+
+ if (unlikely(is_multicast_ether_addr(eth->h_dest))) {
+ if (!compare_ether_addr_64bits(eth->h_dest, dev->broadcast))
+ 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 (unlikely(compare_ether_addr_64bits(eth->h_dest, dev->dev_addr)))
+ skb->pkt_type = PACKET_OTHERHOST;
+ }
+
+ /*
+ * Some variants of DSA tagging don't have an ethertype field
+ * at all, so we check here whether one of those tagging
+ * variants has been configured on the receiving interface,
+ * and if so, set skb->protocol without looking at the packet.
+ */
+ if (netdev_uses_dsa_tags(dev))
+ return htons(ETH_P_DSA);
+ if (netdev_uses_trailer_tags(dev))
+ return htons(ETH_P_TRAILER);
+
+ if (ntohs(eth->h_proto) >= 1536)
+ return eth->h_proto;
+
+ /*
+ * 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 (skb->len >= 2 && *(unsigned short *)(skb->data) == 0xFFFF)
+ return htons(ETH_P_802_3);
+
+ /*
+ * Real 802.2 LLC
+ */
+ return htons(ETH_P_802_2);
+}
+EXPORT_SYMBOL(eth_type_trans);
+
+/**
+ * eth_header_parse - extract hardware address from packet
+ * @skb: packet to extract header from
+ * @haddr: destination buffer
+ */
+int eth_header_parse(const struct sk_buff *skb, unsigned char *haddr)
+{
+ const struct ethhdr *eth = eth_hdr(skb);
+ memcpy(haddr, eth->h_source, ETH_ALEN);
+ return ETH_ALEN;
+}
+EXPORT_SYMBOL(eth_header_parse);
+
+/**
+ * eth_header_cache - fill cache entry from neighbour
+ * @neigh: source neighbour
+ * @hh: destination cache entry
+ * @type: Ethernet type field
+ * Create an Ethernet header template from the neighbour.
+ */
+int eth_header_cache(const struct neighbour *neigh, struct hh_cache *hh, __be16 type)
+{
+ struct ethhdr *eth;
+ const struct net_device *dev = neigh->dev;
+
+ eth = (struct ethhdr *)
+ (((u8 *) hh->hh_data) + (HH_DATA_OFF(sizeof(*eth))));
+
+ if (type == htons(ETH_P_802_3))
+ return -1;
+
+ eth->h_proto = type;
+ memcpy(eth->h_source, dev->dev_addr, ETH_ALEN);
+ memcpy(eth->h_dest, neigh->ha, ETH_ALEN);
+ hh->hh_len = ETH_HLEN;
+ return 0;
+}
+EXPORT_SYMBOL(eth_header_cache);
+
+/**
+ * eth_header_cache_update - update cache entry
+ * @hh: destination cache entry
+ * @dev: network device
+ * @haddr: new hardware address
+ *
+ * Called by Address Resolution module to notify changes in address.
+ */
+void eth_header_cache_update(struct hh_cache *hh,
+ const struct net_device *dev,
+ const unsigned char *haddr)
+{
+ memcpy(((u8 *) hh->hh_data) + HH_DATA_OFF(sizeof(struct ethhdr)),
+ haddr, ETH_ALEN);
+}
+EXPORT_SYMBOL(eth_header_cache_update);
+
+/**
+ * eth_mac_addr - set new Ethernet hardware address
+ * @dev: network device
+ * @p: socket address
+ * Change hardware address of device.
+ *
+ * This doesn't change hardware matching, so needs to be overridden
+ * for most real devices.
+ */
+int eth_mac_addr(struct net_device *dev, void *p)
+{
+ struct sockaddr *addr = p;
+
+ if (netif_running(dev))
+ return -EBUSY;
+ if (!is_valid_ether_addr(addr->sa_data))
+ return -EADDRNOTAVAIL;
+ memcpy(dev->dev_addr, addr->sa_data, ETH_ALEN);
+ /* if device marked as NET_ADDR_RANDOM, reset it */
+ dev->addr_assign_type &= ~NET_ADDR_RANDOM;
+ return 0;
+}
+EXPORT_SYMBOL(eth_mac_addr);
+
+/**
+ * eth_change_mtu - set new MTU size
+ * @dev: network device
+ * @new_mtu: new Maximum Transfer Unit
+ *
+ * Allow changing MTU size. Needs to be overridden for devices
+ * supporting jumbo frames.
+ */
+int eth_change_mtu(struct net_device *dev, int new_mtu)
+{
+ if (new_mtu < 68 || new_mtu > ETH_DATA_LEN)
+ return -EINVAL;
+ dev->mtu = new_mtu;
+ return 0;
+}
+EXPORT_SYMBOL(eth_change_mtu);
+
+int eth_validate_addr(struct net_device *dev)
+{
+ if (!is_valid_ether_addr(dev->dev_addr))
+ return -EADDRNOTAVAIL;
+
+ return 0;
+}
+EXPORT_SYMBOL(eth_validate_addr);
+
+const struct header_ops eth_header_ops ____cacheline_aligned = {
+ .create = eth_header,
+ .parse = eth_header_parse,
+ .rebuild = eth_rebuild_header,
+ .cache = eth_header_cache,
+ .cache_update = eth_header_cache_update,
+};
+
+/**
+ * ether_setup - setup Ethernet network device
+ * @dev: network device
+ * Fill in the fields of the device structure with Ethernet-generic values.
+ */
+void ether_setup(struct net_device *dev)
+{
+ dev->header_ops = &eth_header_ops;
+ dev->type = ARPHRD_ETHER;
+ dev->hard_header_len = ETH_HLEN;
+ dev->mtu = ETH_DATA_LEN;
+ dev->addr_len = ETH_ALEN;
+ dev->tx_queue_len = 1000; /* Ethernet wants good queues */
+ dev->flags = IFF_BROADCAST|IFF_MULTICAST;
+ dev->priv_flags |= IFF_TX_SKB_SHARING;
+
+ memset(dev->broadcast, 0xFF, ETH_ALEN);
+
+}
+EXPORT_SYMBOL(ether_setup);
+
+/**
+ * alloc_etherdev_mqs - Allocates and sets up an Ethernet device
+ * @sizeof_priv: Size of additional driver-private structure to be allocated
+ * for this Ethernet device
+ * @txqs: The number of TX queues this device has.
+ * @rxqs: The number of RX queues this device has.
+ *
+ * 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_mqs(int sizeof_priv, unsigned int txqs,
+ unsigned int rxqs)
+{
+ return alloc_netdev_mqs(sizeof_priv, "eth%d", ether_setup, txqs, rxqs);
+}
+EXPORT_SYMBOL(alloc_etherdev_mqs);
+
+static size_t _format_mac_addr(char *buf, int buflen,
+ const unsigned char *addr, int len)
+{
+ int i;
+ char *cp = buf;
+
+ for (i = 0; i < len; i++) {
+ cp += scnprintf(cp, buflen - (cp - buf), "%02x", addr[i]);
+ if (i == len - 1)
+ break;
+ cp += scnprintf(cp, buflen - (cp - buf), ":");
+ }
+ return cp - buf;
+}
+
+ssize_t sysfs_format_mac(char *buf, const unsigned char *addr, int len)
+{
+ size_t l;
+
+ l = _format_mac_addr(buf, PAGE_SIZE, addr, len);
+ l += scnprintf(buf + l, PAGE_SIZE - l, "\n");
+ return (ssize_t)l;
+}
+EXPORT_SYMBOL(sysfs_format_mac);
generated by cgit (git 2.34.1) at 2024-12-20 11:17:35 +0000