netfilter: factorize ifname_compare()

We use same not trivial helper function in four places. We can factorize it.

Signed-off-by: Eric Dumazet <dada1@cosmosbay.com>
Signed-off-by: Patrick McHardy <kaber@trash.net>
This commit is contained in:
Eric Dumazet
2009-03-25 17:31:52 +01:00
committed by Patrick McHardy
parent 78f3648601
commit b8dfe49877
5 changed files with 30 additions and 74 deletions

View File

@@ -89,25 +89,6 @@ ip6t_ext_hdr(u8 nexthdr)
(nexthdr == IPPROTO_DSTOPTS) );
}
static unsigned long ifname_compare(const char *_a, const char *_b,
const unsigned char *_mask)
{
const unsigned long *a = (const unsigned long *)_a;
const unsigned long *b = (const unsigned long *)_b;
const unsigned long *mask = (const unsigned long *)_mask;
unsigned long ret;
ret = (a[0] ^ b[0]) & mask[0];
if (IFNAMSIZ > sizeof(unsigned long))
ret |= (a[1] ^ b[1]) & mask[1];
if (IFNAMSIZ > 2 * sizeof(unsigned long))
ret |= (a[2] ^ b[2]) & mask[2];
if (IFNAMSIZ > 3 * sizeof(unsigned long))
ret |= (a[3] ^ b[3]) & mask[3];
BUILD_BUG_ON(IFNAMSIZ > 4 * sizeof(unsigned long));
return ret;
}
/* Returns whether matches rule or not. */
/* Performance critical - called for every packet */
static inline bool
@@ -138,7 +119,7 @@ ip6_packet_match(const struct sk_buff *skb,
return false;
}
ret = ifname_compare(indev, ip6info->iniface, ip6info->iniface_mask);
ret = ifname_compare_aligned(indev, ip6info->iniface, ip6info->iniface_mask);
if (FWINV(ret != 0, IP6T_INV_VIA_IN)) {
dprintf("VIA in mismatch (%s vs %s).%s\n",
@@ -147,7 +128,7 @@ ip6_packet_match(const struct sk_buff *skb,
return false;
}
ret = ifname_compare(outdev, ip6info->outiface, ip6info->outiface_mask);
ret = ifname_compare_aligned(outdev, ip6info->outiface, ip6info->outiface_mask);
if (FWINV(ret != 0, IP6T_INV_VIA_OUT)) {
dprintf("VIA out mismatch (%s vs %s).%s\n",