diff options
Diffstat (limited to 'kernel/net/ethernet/eth.c')
| -rw-r--r-- | kernel/net/ethernet/eth.c | 484 |
1 files changed, 484 insertions, 0 deletions
diff --git a/kernel/net/ethernet/eth.c b/kernel/net/ethernet/eth.c new file mode 100644 index 000000000..f3bad41d7 --- /dev/null +++ b/kernel/net/ethernet/eth.c @@ -0,0 +1,484 @@ +/* + * 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 <linux/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 int 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)) { + eth_zero_addr(eth->h_dest); + return ETH_HLEN; + } + + return -ETH_HLEN; +} +EXPORT_SYMBOL(eth_header); + +/** + * eth_get_headlen - determine the the length of header for an ethernet frame + * @data: pointer to start of frame + * @len: total length of frame + * + * Make a best effort attempt to pull the length for all of the headers for + * a given frame in a linear buffer. + */ +u32 eth_get_headlen(void *data, unsigned int len) +{ + const struct ethhdr *eth = (const struct ethhdr *)data; + struct flow_keys keys; + + /* this should never happen, but better safe than sorry */ + if (len < sizeof(*eth)) + return len; + + /* parse any remaining L2/L3 headers, check for L4 */ + if (!__skb_flow_dissect(NULL, &keys, data, + eth->h_proto, sizeof(*eth), len)) + return max_t(u32, keys.thoff, sizeof(*eth)); + + /* parse for any L4 headers */ + return min_t(u32, __skb_get_poff(NULL, data, &keys, len), len); +} +EXPORT_SYMBOL(eth_get_headlen); + +/** + * 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) +{ + unsigned short _service_access_point; + const unsigned short *sap; + const 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 (ether_addr_equal_64bits(eth->h_dest, dev->broadcast)) + skb->pkt_type = PACKET_BROADCAST; + else + skb->pkt_type = PACKET_MULTICAST; + } + else if (unlikely(!ether_addr_equal_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 (unlikely(netdev_uses_dsa(dev))) + return htons(ETH_P_XDSA); + + if (likely(ntohs(eth->h_proto) >= ETH_P_802_3_MIN)) + 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. + */ + sap = skb_header_pointer(skb, 0, sizeof(*sap), &_service_access_point); + if (sap && *sap == 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_prepare_mac_addr_change - prepare for mac change + * @dev: network device + * @p: socket address + */ +int eth_prepare_mac_addr_change(struct net_device *dev, void *p) +{ + struct sockaddr *addr = p; + + if (!(dev->priv_flags & IFF_LIVE_ADDR_CHANGE) && netif_running(dev)) + return -EBUSY; + if (!is_valid_ether_addr(addr->sa_data)) + return -EADDRNOTAVAIL; + return 0; +} +EXPORT_SYMBOL(eth_prepare_mac_addr_change); + +/** + * eth_commit_mac_addr_change - commit mac change + * @dev: network device + * @p: socket address + */ +void eth_commit_mac_addr_change(struct net_device *dev, void *p) +{ + struct sockaddr *addr = p; + + memcpy(dev->dev_addr, addr->sa_data, ETH_ALEN); +} +EXPORT_SYMBOL(eth_commit_mac_addr_change); + +/** + * 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) +{ + int ret; + + ret = eth_prepare_mac_addr_change(dev, p); + if (ret < 0) + return ret; + eth_commit_mac_addr_change(dev, p); + 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, + .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 = ð_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; + + eth_broadcast_addr(dev->broadcast); + +} +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", NET_NAME_UNKNOWN, + ether_setup, txqs, rxqs); +} +EXPORT_SYMBOL(alloc_etherdev_mqs); + +ssize_t sysfs_format_mac(char *buf, const unsigned char *addr, int len) +{ + return scnprintf(buf, PAGE_SIZE, "%*phC\n", len, addr); +} +EXPORT_SYMBOL(sysfs_format_mac); + +struct sk_buff **eth_gro_receive(struct sk_buff **head, + struct sk_buff *skb) +{ + struct sk_buff *p, **pp = NULL; + struct ethhdr *eh, *eh2; + unsigned int hlen, off_eth; + const struct packet_offload *ptype; + __be16 type; + int flush = 1; + + off_eth = skb_gro_offset(skb); + hlen = off_eth + sizeof(*eh); + eh = skb_gro_header_fast(skb, off_eth); + if (skb_gro_header_hard(skb, hlen)) { + eh = skb_gro_header_slow(skb, hlen, off_eth); + if (unlikely(!eh)) + goto out; + } + + flush = 0; + + for (p = *head; p; p = p->next) { + if (!NAPI_GRO_CB(p)->same_flow) + continue; + + eh2 = (struct ethhdr *)(p->data + off_eth); + if (compare_ether_header(eh, eh2)) { + NAPI_GRO_CB(p)->same_flow = 0; + continue; + } + } + + type = eh->h_proto; + + rcu_read_lock(); + ptype = gro_find_receive_by_type(type); + if (ptype == NULL) { + flush = 1; + goto out_unlock; + } + + skb_gro_pull(skb, sizeof(*eh)); + skb_gro_postpull_rcsum(skb, eh, sizeof(*eh)); + pp = ptype->callbacks.gro_receive(head, skb); + +out_unlock: + rcu_read_unlock(); +out: + NAPI_GRO_CB(skb)->flush |= flush; + + return pp; +} +EXPORT_SYMBOL(eth_gro_receive); + +int eth_gro_complete(struct sk_buff *skb, int nhoff) +{ + struct ethhdr *eh = (struct ethhdr *)(skb->data + nhoff); + __be16 type = eh->h_proto; + struct packet_offload *ptype; + int err = -ENOSYS; + + if (skb->encapsulation) + skb_set_inner_mac_header(skb, nhoff); + + rcu_read_lock(); + ptype = gro_find_complete_by_type(type); + if (ptype != NULL) + err = ptype->callbacks.gro_complete(skb, nhoff + + sizeof(struct ethhdr)); + + rcu_read_unlock(); + return err; +} +EXPORT_SYMBOL(eth_gro_complete); + +static struct packet_offload eth_packet_offload __read_mostly = { + .type = cpu_to_be16(ETH_P_TEB), + .callbacks = { + .gro_receive = eth_gro_receive, + .gro_complete = eth_gro_complete, + }, +}; + +static int __init eth_offload_init(void) +{ + dev_add_offload(ð_packet_offload); + + return 0; +} + +fs_initcall(eth_offload_init); |