net/ipv4: Move device validation to helper

Move the device matching check in __fib_validate_source to a helper and
export it for use by netfilter modules. Code move only; no functional
change intended.

Signed-off-by: David Ahern <dsahern@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
David Ahern 2018-09-20 13:50:47 -07:00 committed by David S. Miller
parent 5678cb3c96
commit 78f2756c5f
2 changed files with 28 additions and 17 deletions

View File

@ -373,6 +373,7 @@ static inline bool fib4_rules_early_flow_dissect(struct net *net,
extern const struct nla_policy rtm_ipv4_policy[];
void ip_fib_init(void);
__be32 fib_compute_spec_dst(struct sk_buff *skb);
bool fib_info_nh_uses_dev(struct fib_info *fi, const struct net_device *dev);
int fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst,
u8 tos, int oif, struct net_device *dev,
struct in_device *idev, u32 *itag);

View File

@ -315,6 +315,32 @@ __be32 fib_compute_spec_dst(struct sk_buff *skb)
return inet_select_addr(dev, ip_hdr(skb)->saddr, scope);
}
bool fib_info_nh_uses_dev(struct fib_info *fi, const struct net_device *dev)
{
bool dev_match = false;
int ret;
#ifdef CONFIG_IP_ROUTE_MULTIPATH
for (ret = 0; ret < fi->fib_nhs; ret++) {
struct fib_nh *nh = &fi->fib_nh[ret];
if (nh->nh_dev == dev) {
dev_match = true;
break;
} else if (l3mdev_master_ifindex_rcu(nh->nh_dev) == dev->ifindex) {
dev_match = true;
break;
}
}
#else
if (fi->fib_nh[0].nh_dev == dev)
dev_match = true;
#endif
return dev_match;
}
EXPORT_SYMBOL_GPL(fib_info_nh_uses_dev);
/* Given (packet source, input interface) and optional (dst, oif, tos):
* - (main) check, that source is valid i.e. not broadcast or our local
* address.
@ -361,24 +387,8 @@ static int __fib_validate_source(struct sk_buff *skb, __be32 src, __be32 dst,
(res.type != RTN_LOCAL || !IN_DEV_ACCEPT_LOCAL(idev)))
goto e_inval;
fib_combine_itag(itag, &res);
dev_match = false;
#ifdef CONFIG_IP_ROUTE_MULTIPATH
for (ret = 0; ret < res.fi->fib_nhs; ret++) {
struct fib_nh *nh = &res.fi->fib_nh[ret];
if (nh->nh_dev == dev) {
dev_match = true;
break;
} else if (l3mdev_master_ifindex_rcu(nh->nh_dev) == dev->ifindex) {
dev_match = true;
break;
}
}
#else
if (FIB_RES_DEV(res) == dev)
dev_match = true;
#endif
dev_match = fib_info_nh_uses_dev(res.fi, dev);
if (dev_match) {
ret = FIB_RES_NH(res).nh_scope >= RT_SCOPE_HOST;
return ret;