arp: decompose is_garp logic into a separate function

The code is quite involving already to earn a separate function for
itself. If anything, it helps arp_process readability.

Signed-off-by: Ihar Hrachyshka <ihrachys@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Ihar Hrachyshka 2017-05-18 12:41:19 -07:00 committed by David S. Miller
parent 34eb5fe078
commit 6fd05633bd
1 changed files with 23 additions and 12 deletions

View File

@ -641,6 +641,27 @@ void arp_xmit(struct sk_buff *skb)
}
EXPORT_SYMBOL(arp_xmit);
static bool arp_is_garp(struct net_device *dev, int addr_type,
__be16 ar_op,
__be32 sip, __be32 tip,
unsigned char *sha, unsigned char *tha)
{
bool is_garp = tip == sip && addr_type == RTN_UNICAST;
/* Gratuitous ARP _replies_ also require target hwaddr to be
* the same as source.
*/
if (is_garp && ar_op == htons(ARPOP_REPLY))
is_garp =
/* IPv4 over IEEE 1394 doesn't provide target
* hardware address field in its ARP payload.
*/
tha &&
!memcmp(tha, sha, dev->addr_len);
return is_garp;
}
/*
* Process an arp request.
*/
@ -844,18 +865,8 @@ static int arp_process(struct net *net, struct sock *sk, struct sk_buff *skb)
It is possible, that this option should be enabled for some
devices (strip is candidate)
*/
is_garp = tip == sip && addr_type == RTN_UNICAST;
/* Gratuitous ARP _replies_ also require target hwaddr to be
* the same as source.
*/
if (is_garp && arp->ar_op == htons(ARPOP_REPLY))
is_garp =
/* IPv4 over IEEE 1394 doesn't provide target
* hardware address field in its ARP payload.
*/
tha &&
!memcmp(tha, sha, dev->addr_len);
is_garp = arp_is_garp(dev, addr_type, arp->ar_op,
sip, tip, sha, tha);
if (!n &&
((arp->ar_op == htons(ARPOP_REPLY) &&