static bool rpfilter_lookup_reverse(struct net *net, struct flowi4 *fl4,
const struct net_device *dev, u8 flags)
{
struct fib_result res;
bool dev_match;
int ret __maybe_unused;
if (fib_lookup(net, fl4, &res, FIB_LOOKUP_IGNORE_LINKSTATE))
return false;
if (res.type != RTN_UNICAST) {
if (res.type != RTN_LOCAL || !(flags & XT_RPFILTER_ACCEPT_LOCAL))
return false;
}
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 (FIB_RES_DEV(res) == dev)
dev_match = true;
#endif
return dev_match || flags & XT_RPFILTER_LOOSE;
}
static bool rpfilter_lookup_reverse(struct flowi4 *fl4,
const struct net_device *dev, u8 flags)
{
struct fib_result res;
bool dev_match;
struct net *net = dev_net(dev);
int ret __maybe_unused;
if (fib_lookup(net, fl4, &res))
return false;
if (res.type != RTN_UNICAST) {
if (res.type != RTN_LOCAL || !(flags & XT_RPFILTER_ACCEPT_LOCAL))
return false;
}
dev_match = false;
//#ifdef CONFIG_IP_ROUTE_MULTIPATH
#if (defined CONFIG_IP_ROUTE_MULTIPATH) || (defined CONFIG_IP_ROUTE_DEFLECTION)
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 (FIB_RES_DEV(res) == dev)
dev_match = true;
#endif
if (dev_match || flags & XT_RPFILTER_LOOSE)
return FIB_RES_NH(res).nh_scope <= RT_SCOPE_HOST;
return dev_match;
}
struct net_device * ip_dev_find(u32 addr)
{
struct flowi fl = { .nl_u = { .ip4_u = { .daddr = addr } } };
struct fib_result res;
struct net_device *dev = NULL;
#ifdef CONFIG_IP_MULTIPLE_TABLES
res.r = NULL;
#endif
if (!local_table || local_table->tb_lookup(local_table, &fl, &res)) {
return NULL;
}
if (res.type != RTN_LOCAL)
goto out;
dev = FIB_RES_DEV(res);
if (dev)
atomic_inc(&dev->refcnt);
out:
fib_res_put(&res);
return dev;
}
struct net_device * ip_dev_find(struct net *net, __be32 addr)
{
struct flowi fl = { .nl_u = { .ip4_u = { .daddr = addr } } };
struct fib_result res;
struct net_device *dev = NULL;
struct fib_table *local_table;
#ifdef CONFIG_IP_MULTIPLE_TABLES
res.r = NULL;
#endif
local_table = fib_get_table(net, RT_TABLE_LOCAL);
if (!local_table || local_table->tb_lookup(local_table, &fl, &res))
return NULL;
if (res.type != RTN_LOCAL)
goto out;
dev = FIB_RES_DEV(res);
if (dev)
dev_hold(dev);
out:
fib_res_put(&res);
return dev;
}
void nft_fib4_eval(const struct nft_expr *expr, struct nft_regs *regs,
const struct nft_pktinfo *pkt)
{
const struct nft_fib *priv = nft_expr_priv(expr);
int noff = skb_network_offset(pkt->skb);
u32 *dest = ®s->data[priv->dreg];
struct iphdr *iph, _iph;
struct fib_result res;
struct flowi4 fl4 = {
.flowi4_scope = RT_SCOPE_UNIVERSE,
.flowi4_iif = LOOPBACK_IFINDEX,
};
const struct net_device *oif;
struct net_device *found;
#ifdef CONFIG_IP_ROUTE_MULTIPATH
int i;
#endif
/*
* Do not set flowi4_oif, it restricts results (for example, asking
* for oif 3 will get RTN_UNICAST result even if the daddr exits
* on another interface.
*
* Search results for the desired outinterface instead.
*/
if (priv->flags & NFTA_FIB_F_OIF)
oif = nft_out(pkt);
else if (priv->flags & NFTA_FIB_F_IIF)
oif = nft_in(pkt);
else
oif = NULL;
if (nft_hook(pkt) == NF_INET_PRE_ROUTING &&
nft_fib_is_loopback(pkt->skb, nft_in(pkt))) {
nft_fib_store_result(dest, priv, pkt,
nft_in(pkt)->ifindex);
return;
}
iph = skb_header_pointer(pkt->skb, noff, sizeof(_iph), &_iph);
if (!iph) {
regs->verdict.code = NFT_BREAK;
return;
}
if (ipv4_is_zeronet(iph->saddr)) {
if (ipv4_is_lbcast(iph->daddr) ||
ipv4_is_local_multicast(iph->daddr)) {
nft_fib_store_result(dest, priv, pkt,
get_ifindex(pkt->skb->dev));
return;
}
}
if (priv->flags & NFTA_FIB_F_MARK)
fl4.flowi4_mark = pkt->skb->mark;
fl4.flowi4_tos = iph->tos & DSCP_BITS;
if (priv->flags & NFTA_FIB_F_DADDR) {
fl4.daddr = iph->daddr;
fl4.saddr = get_saddr(iph->saddr);
} else {
fl4.daddr = iph->saddr;
fl4.saddr = get_saddr(iph->daddr);
}
*dest = 0;
if (fib_lookup(nft_net(pkt), &fl4, &res, FIB_LOOKUP_IGNORE_LINKSTATE))
return;
switch (res.type) {
case RTN_UNICAST:
break;
case RTN_LOCAL: /* Should not see RTN_LOCAL here */
return;
default:
break;
}
if (!oif) {
found = FIB_RES_DEV(res);
goto ok;
}
#ifdef CONFIG_IP_ROUTE_MULTIPATH
for (i = 0; i < res.fi->fib_nhs; i++) {
struct fib_nh *nh = &res.fi->fib_nh[i];
if (nh->nh_dev == oif) {
found = nh->nh_dev;
goto ok;
}
}
return;
#else
found = FIB_RES_DEV(res);
if (found != oif)
return;
#endif
ok:
switch (priv->result) {
case NFT_FIB_RESULT_OIF:
*dest = found->ifindex;
break;
case NFT_FIB_RESULT_OIFNAME:
strncpy((char *)dest, found->name, IFNAMSIZ);
break;
default:
WARN_ON_ONCE(1);
break;
}
}
