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Diffstat (limited to 'net/ethernet/eth.c')
-rw-r--r--net/ethernet/eth.c196
1 files changed, 115 insertions, 81 deletions
diff --git a/net/ethernet/eth.c b/net/ethernet/eth.c
index 387c71c584e..43863933f27 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.
*/
generated by cgit v1.2.3 (git 2.39.1) at 2024-04-27 01:10:51 +0000