diff options
Diffstat (limited to 'net/ethernet/eth.c')
| -rw-r--r-- | net/ethernet/eth.c | 196 |
1 files changed, 115 insertions, 81 deletions
diff --git a/net/ethernet/eth.c b/net/ethernet/eth.c index 387c71c584ee..43863933f27f 100644 --- a/net/ethernet/eth.c +++ b/net/ethernet/eth.c @@ -64,81 +64,79 @@ __setup("ether=", netdev_boot_setup); -/* - * Create the Ethernet MAC header for an arbitrary protocol layer +/** + * 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) * - * saddr=NULL means use device source address - * daddr=NULL means leave destination address (eg unresolved arp) + * + * 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. */ - int eth_header(struct sk_buff *skb, struct net_device *dev, unsigned short type, - void *daddr, void *saddr, unsigned len) + void *daddr, void *saddr, unsigned len) { - struct ethhdr *eth = (struct ethhdr *)skb_push(skb,ETH_HLEN); + 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) + if (type != ETH_P_802_3) eth->h_proto = htons(type); else eth->h_proto = htons(len); /* - * Set the source hardware address. + * Set the source hardware address. */ - - if(!saddr) + + if (!saddr) saddr = dev->dev_addr; - memcpy(eth->h_source,saddr,dev->addr_len); + memcpy(eth->h_source, saddr, dev->addr_len); - if(daddr) - { - memcpy(eth->h_dest,daddr,dev->addr_len); + if (daddr) { + memcpy(eth->h_dest, daddr, dev->addr_len); return ETH_HLEN; } - + /* - * Anyway, the loopback-device should never use this function... + * Anyway, the loopback-device should never use this function... */ - if (dev->flags & (IFF_LOOPBACK|IFF_NOARP)) - { + if (dev->flags & (IFF_LOOPBACK | IFF_NOARP)) { memset(eth->h_dest, 0, 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. +/** + * eth_rebuild_header- rebuild the Ethernet MAC header. + * @skb: socket buffer to update * - * This routine CANNOT use cached dst->neigh! - * Really, it is used only when dst->neigh is wrong. + * 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) - { + switch (eth->h_proto) { #ifdef CONFIG_INET case __constant_htons(ETH_P_IP): - return arp_find(eth->h_dest, skb); -#endif + return arp_find(eth->h_dest, skb); +#endif default: printk(KERN_DEBUG - "%s: unable to resolve type %X addresses.\n", + "%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; } @@ -146,62 +144,70 @@ int eth_rebuild_header(struct sk_buff *skb) 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. +/** + * 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; unsigned char *rawp; - + skb->mac.raw = skb->data; - skb_pull(skb,ETH_HLEN); + skb_pull(skb, ETH_HLEN); eth = eth_hdr(skb); - + if (is_multicast_ether_addr(eth->h_dest)) { if (!compare_ether_addr(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. + * 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. + * Seems, you forgot to remove it. All silly devices + * seems to set IFF_PROMISC. */ - - else if(1 /*dev->flags&IFF_PROMISC*/) { + + else if (1 /*dev->flags&IFF_PROMISC */ ) { if (unlikely(compare_ether_addr(eth->h_dest, dev->dev_addr))) 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. + * 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 + * 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 + */ static int eth_header_parse(struct sk_buff *skb, unsigned char *haddr) { struct ethhdr *eth = eth_hdr(skb); @@ -209,14 +215,20 @@ static int eth_header_parse(struct sk_buff *skb, unsigned char *haddr) return ETH_ALEN; } +/** + * eth_header_cache - fill cache entry from neighbour + * @neigh: source neighbour + * @hh: destination cache entry + * Create an Ethernet header template from the neighbour. + */ 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)))); + eth = (struct ethhdr *) + (((u8 *) hh->hh_data) + (HH_DATA_OFF(sizeof(*eth)))); if (type == __constant_htons(ETH_P_802_3)) return -1; @@ -228,27 +240,47 @@ int eth_header_cache(struct neighbour *neigh, struct hh_cache *hh) return 0; } -/* +/** + * 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, struct net_device *dev, unsigned char * haddr) +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)), + memcpy(((u8 *) hh->hh_data) + HH_DATA_OFF(sizeof(struct ethhdr)), haddr, dev->addr_len); } -EXPORT_SYMBOL(eth_type_trans); - +/** + * 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. + */ static int eth_mac_addr(struct net_device *dev, void *p) { - struct sockaddr *addr=p; + struct sockaddr *addr = p; if (netif_running(dev)) return -EBUSY; - memcpy(dev->dev_addr, addr->sa_data,dev->addr_len); + memcpy(dev->dev_addr, addr->sa_data, dev->addr_len); return 0; } +/** + * 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. + */ static int eth_change_mtu(struct net_device *dev, int new_mtu) { if (new_mtu < 68 || new_mtu > ETH_DATA_LEN) @@ -257,8 +289,10 @@ static int eth_change_mtu(struct net_device *dev, int new_mtu) return 0; } -/* - * Fill in the fields of the device structure with ethernet-generic values. +/** + * 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) { @@ -277,21 +311,21 @@ void ether_setup(struct net_device *dev) dev->tx_queue_len = 1000; /* Ethernet wants good queues */ dev->flags = IFF_BROADCAST|IFF_MULTICAST; - memset(dev->broadcast,0xFF, ETH_ALEN); + memset(dev->broadcast, 0xFF, ETH_ALEN); } EXPORT_SYMBOL(ether_setup); /** - * alloc_etherdev - Allocates and sets up an ethernet device + * alloc_etherdev - Allocates and sets up an Ethernet device * @sizeof_priv: Size of additional driver-private structure to be allocated - * for this ethernet device + * for this Ethernet device * - * Fill in the fields of the device structure with ethernet-generic + * 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 + * size (sizeof_priv). A 32-byte (not bit) alignment is enforced for * this private data area. */ |