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|
--- a/include/linux/rtnetlink.h
+++ b/include/linux/rtnetlink.h
@@ -293,6 +293,8 @@
#define RTNH_F_DEAD 1 /* Nexthop is dead (used by multipath) */
#define RTNH_F_PERVASIVE 2 /* Do recursive gateway lookup */
#define RTNH_F_ONLINK 4 /* Gateway is forced on link */
+#define RTNH_F_SUSPECT 8 /* We don't know the real state */
+#define RTNH_F_BADSTATE (RTNH_F_DEAD | RTNH_F_SUSPECT)
/* Macros to handle hexthops */
--- a/include/net/flow.h
+++ b/include/net/flow.h
@@ -19,6 +19,8 @@
struct {
__be32 daddr;
__be32 saddr;
+ __u32 lsrc;
+ __u32 gw;
__u8 tos;
__u8 scope;
} ip4_u;
@@ -43,6 +45,8 @@
#define fl6_flowlabel nl_u.ip6_u.flowlabel
#define fl4_dst nl_u.ip4_u.daddr
#define fl4_src nl_u.ip4_u.saddr
+#define fl4_lsrc nl_u.ip4_u.lsrc
+#define fl4_gw nl_u.ip4_u.gw
#define fl4_tos nl_u.ip4_u.tos
#define fl4_scope nl_u.ip4_u.scope
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -1116,6 +1116,7 @@
/* Gateway is different ... */
rt->rt_gateway = new_gw;
+ if (rt->fl.fl4_gw) rt->fl.fl4_gw = new_gw;
/* Redirect received -> path was valid */
dst_confirm(&rth->u.dst);
@@ -1551,6 +1552,7 @@
rth->fl.fl4_tos = tos;
rth->fl.mark = skb->mark;
rth->fl.fl4_src = saddr;
+ rth->fl.fl4_lsrc = 0;
rth->rt_src = saddr;
#ifdef CONFIG_NET_CLS_ROUTE
rth->u.dst.tclassid = itag;
@@ -1561,6 +1563,7 @@
dev_hold(rth->u.dst.dev);
rth->idev = in_dev_get(rth->u.dst.dev);
rth->fl.oif = 0;
+ rth->fl.fl4_gw = 0;
rth->rt_gateway = daddr;
rth->rt_spec_dst= spec_dst;
rth->rt_type = RTN_MULTICAST;
@@ -1624,7 +1627,7 @@
static inline int __mkroute_input(struct sk_buff *skb,
struct fib_result* res,
struct in_device *in_dev,
- __be32 daddr, __be32 saddr, u32 tos,
+ __be32 daddr, __be32 saddr, u32 tos, u32 lsrc,
struct rtable **result)
{
@@ -1659,6 +1662,7 @@
flags |= RTCF_DIRECTSRC;
if (out_dev == in_dev && err && !(flags & (RTCF_NAT | RTCF_MASQ)) &&
+ !lsrc &&
(IN_DEV_SHARED_MEDIA(out_dev) ||
inet_addr_onlink(out_dev, saddr, FIB_RES_GW(*res))))
flags |= RTCF_DOREDIRECT;
@@ -1692,6 +1696,7 @@
rth->fl.mark = skb->mark;
rth->fl.fl4_src = saddr;
rth->rt_src = saddr;
+ rth->fl.fl4_lsrc = lsrc;
rth->rt_gateway = daddr;
rth->rt_iif =
rth->fl.iif = in_dev->dev->ifindex;
@@ -1699,6 +1704,7 @@
dev_hold(rth->u.dst.dev);
rth->idev = in_dev_get(rth->u.dst.dev);
rth->fl.oif = 0;
+ rth->fl.fl4_gw = 0;
rth->rt_spec_dst= spec_dst;
rth->u.dst.input = ip_forward;
@@ -1720,19 +1726,21 @@
struct fib_result* res,
const struct flowi *fl,
struct in_device *in_dev,
- __be32 daddr, __be32 saddr, u32 tos)
+ __be32 daddr, __be32 saddr, u32 tos,
+ u32 lsrc)
{
struct rtable* rth = NULL;
int err;
unsigned hash;
+ fib_select_default(fl, res);
#ifdef CONFIG_IP_ROUTE_MULTIPATH
- if (res->fi && res->fi->fib_nhs > 1 && fl->oif == 0)
+ if (res->fi && res->fi->fib_nhs > 1)
fib_select_multipath(fl, res);
#endif
/* create a routing cache entry */
- err = __mkroute_input(skb, res, in_dev, daddr, saddr, tos, &rth);
+ err = __mkroute_input(skb, res, in_dev, daddr, saddr, tos, lsrc, &rth);
if (err)
return err;
@@ -1752,18 +1760,18 @@
*/
static int ip_route_input_slow(struct sk_buff *skb, __be32 daddr, __be32 saddr,
- u8 tos, struct net_device *dev)
+ u8 tos, struct net_device *dev, u32 lsrc)
{
struct fib_result res;
struct in_device *in_dev = in_dev_get(dev);
struct flowi fl = { .nl_u = { .ip4_u =
{ .daddr = daddr,
- .saddr = saddr,
+ .saddr = lsrc ? : saddr,
.tos = tos,
.scope = RT_SCOPE_UNIVERSE,
} },
.mark = skb->mark,
- .iif = dev->ifindex };
+ .iif = lsrc? loopback_dev.ifindex : dev->ifindex };
unsigned flags = 0;
u32 itag = 0;
struct rtable * rth;
@@ -1796,6 +1804,12 @@
if (BADCLASS(daddr) || ZERONET(daddr) || LOOPBACK(daddr))
goto martian_destination;
+ if (lsrc) {
+ if (MULTICAST(lsrc) || BADCLASS(lsrc) ||
+ ZERONET(lsrc) || LOOPBACK(lsrc))
+ goto e_inval;
+ }
+
/*
* Now we are ready to route packet.
*/
@@ -1805,6 +1819,10 @@
goto no_route;
}
free_res = 1;
+ if (lsrc && res.type != RTN_UNICAST && res.type != RTN_NAT)
+ goto e_inval;
+ fl.iif = dev->ifindex;
+ fl.fl4_src = saddr;
RT_CACHE_STAT_INC(in_slow_tot);
@@ -1829,7 +1847,7 @@
if (res.type != RTN_UNICAST)
goto martian_destination;
- err = ip_mkroute_input(skb, &res, &fl, in_dev, daddr, saddr, tos);
+ err = ip_mkroute_input(skb, &res, &fl, in_dev, daddr, saddr, tos, lsrc);
if (err == -ENOBUFS)
goto e_nobufs;
if (err == -EINVAL)
@@ -1844,6 +1862,8 @@
brd_input:
if (skb->protocol != htons(ETH_P_IP))
goto e_inval;
+ if (lsrc)
+ goto e_inval;
if (ZERONET(saddr))
spec_dst = inet_select_addr(dev, 0, RT_SCOPE_LINK);
@@ -1884,6 +1904,7 @@
rth->u.dst.dev = &loopback_dev;
dev_hold(rth->u.dst.dev);
rth->idev = in_dev_get(rth->u.dst.dev);
+ rth->fl.fl4_gw = 0;
rth->rt_gateway = daddr;
rth->rt_spec_dst= spec_dst;
rth->u.dst.input= ip_local_deliver;
@@ -1933,8 +1954,9 @@
goto e_inval;
}
-int ip_route_input(struct sk_buff *skb, __be32 daddr, __be32 saddr,
- u8 tos, struct net_device *dev)
+static inline int
+ip_route_input_cached(struct sk_buff *skb, __be32 daddr, __be32 saddr,
+ u8 tos, struct net_device *dev, u32 lsrc)
{
struct rtable * rth;
unsigned hash;
@@ -1949,6 +1971,7 @@
if (rth->fl.fl4_dst == daddr &&
rth->fl.fl4_src == saddr &&
rth->fl.iif == iif &&
+ rth->fl.fl4_lsrc == lsrc &&
rth->fl.oif == 0 &&
rth->fl.mark == skb->mark &&
rth->fl.fl4_tos == tos) {
@@ -1995,7 +2018,19 @@
rcu_read_unlock();
return -EINVAL;
}
- return ip_route_input_slow(skb, daddr, saddr, tos, dev);
+ return ip_route_input_slow(skb, daddr, saddr, tos, dev, lsrc);
+}
+
+int ip_route_input(struct sk_buff *skb, u32 daddr, u32 saddr,
+ u8 tos, struct net_device *dev)
+{
+ return ip_route_input_cached(skb, daddr, saddr, tos, dev, 0);
+}
+
+int ip_route_input_lookup(struct sk_buff *skb, u32 daddr, u32 saddr,
+ u8 tos, struct net_device *dev, u32 lsrc)
+{
+ return ip_route_input_cached(skb, daddr, saddr, tos, dev, lsrc);
}
static inline int __mkroute_output(struct rtable **result,
@@ -2067,6 +2102,7 @@
rth->fl.fl4_tos = tos;
rth->fl.fl4_src = oldflp->fl4_src;
rth->fl.oif = oldflp->oif;
+ rth->fl.fl4_gw = oldflp->fl4_gw;
rth->fl.mark = oldflp->mark;
rth->rt_dst = fl->fl4_dst;
rth->rt_src = fl->fl4_src;
@@ -2145,6 +2181,7 @@
struct flowi fl = { .nl_u = { .ip4_u =
{ .daddr = oldflp->fl4_dst,
.saddr = oldflp->fl4_src,
+ .gw = oldflp->fl4_gw,
.tos = tos & IPTOS_RT_MASK,
.scope = ((tos & RTO_ONLINK) ?
RT_SCOPE_LINK :
@@ -2248,6 +2285,7 @@
dev_out = &loopback_dev;
dev_hold(dev_out);
fl.oif = loopback_dev.ifindex;
+ fl.fl4_gw = 0;
res.type = RTN_LOCAL;
flags |= RTCF_LOCAL;
goto make_route;
@@ -2255,7 +2293,7 @@
if (fib_lookup(&fl, &res)) {
res.fi = NULL;
- if (oldflp->oif) {
+ if (oldflp->oif && dev_out->flags & IFF_UP) {
/* Apparently, routing tables are wrong. Assume,
that the destination is on link.
@@ -2295,6 +2333,7 @@
dev_out = &loopback_dev;
dev_hold(dev_out);
fl.oif = dev_out->ifindex;
+ fl.fl4_gw = 0;
if (res.fi)
fib_info_put(res.fi);
res.fi = NULL;
@@ -2302,13 +2341,12 @@
goto make_route;
}
+ if (res.type == RTN_UNICAST)
+ fib_select_default(&fl, &res);
#ifdef CONFIG_IP_ROUTE_MULTIPATH
- if (res.fi->fib_nhs > 1 && fl.oif == 0)
+ if (res.fi->fib_nhs > 1)
fib_select_multipath(&fl, &res);
- else
#endif
- if (!res.prefixlen && res.type == RTN_UNICAST && !fl.oif)
- fib_select_default(&fl, &res);
if (!fl.fl4_src)
fl.fl4_src = FIB_RES_PREFSRC(res);
@@ -2345,6 +2383,7 @@
rth->fl.fl4_src == flp->fl4_src &&
rth->fl.iif == 0 &&
rth->fl.oif == flp->oif &&
+ rth->fl.fl4_gw == flp->fl4_gw &&
rth->fl.mark == flp->mark &&
!((rth->fl.fl4_tos ^ flp->fl4_tos) &
(IPTOS_RT_MASK | RTO_ONLINK))) {
@@ -3030,3 +3069,4 @@
EXPORT_SYMBOL(__ip_select_ident);
EXPORT_SYMBOL(ip_route_input);
EXPORT_SYMBOL(ip_route_output_key);
+EXPORT_SYMBOL(ip_route_input_lookup);
|
