From a210d01ae3ee006b59e54e772a7f212486e0f021 Mon Sep 17 00:00:00 2001 From: Julian Anastasov Date: Wed, 1 Oct 2008 07:28:28 -0700 Subject: [PATCH] ipv4: Loosen source address check on IPv4 output ip_route_output() contains a check to make sure that no flows with non-local source IP addresses are routed. This obviously makes using such addresses impossible. This patch introduces a flowi flag which makes omitting this check possible. The new flag provides a way of handling transparent and non-transparent connections differently. Signed-off-by: Julian Anastasov Signed-off-by: KOVACS Krisztian Signed-off-by: David S. Miller --- include/net/flow.h | 2 ++ net/ipv4/route.c | 20 +++++++++++++------- 2 files changed, 15 insertions(+), 7 deletions(-) diff --git a/include/net/flow.h b/include/net/flow.h index 228b2477ceec..b45a5e4fcadd 100644 --- a/include/net/flow.h +++ b/include/net/flow.h @@ -47,6 +47,8 @@ struct flowi { #define fl4_scope nl_u.ip4_u.scope __u8 proto; + __u8 flags; +#define FLOWI_FLAG_ANYSRC 0x01 union { struct { __be16 sport; diff --git a/net/ipv4/route.c b/net/ipv4/route.c index f62187bb6d08..a6d7c584f53b 100644 --- a/net/ipv4/route.c +++ b/net/ipv4/route.c @@ -2361,11 +2361,6 @@ static int ip_route_output_slow(struct net *net, struct rtable **rp, ipv4_is_zeronet(oldflp->fl4_src)) goto out; - /* It is equivalent to inet_addr_type(saddr) == RTN_LOCAL */ - dev_out = ip_dev_find(net, oldflp->fl4_src); - if (dev_out == NULL) - goto out; - /* I removed check for oif == dev_out->oif here. It was wrong for two reasons: 1. ip_dev_find(net, saddr) can return wrong iface, if saddr @@ -2377,6 +2372,11 @@ static int ip_route_output_slow(struct net *net, struct rtable **rp, if (oldflp->oif == 0 && (ipv4_is_multicast(oldflp->fl4_dst) || oldflp->fl4_dst == htonl(0xFFFFFFFF))) { + /* It is equivalent to inet_addr_type(saddr) == RTN_LOCAL */ + dev_out = ip_dev_find(net, oldflp->fl4_src); + if (dev_out == NULL) + goto out; + /* Special hack: user can direct multicasts and limited broadcast via necessary interface without fiddling with IP_MULTICAST_IF or IP_PKTINFO. @@ -2395,9 +2395,15 @@ static int ip_route_output_slow(struct net *net, struct rtable **rp, fl.oif = dev_out->ifindex; goto make_route; } - if (dev_out) + + if (!(oldflp->flags & FLOWI_FLAG_ANYSRC)) { + /* It is equivalent to inet_addr_type(saddr) == RTN_LOCAL */ + dev_out = ip_dev_find(net, oldflp->fl4_src); + if (dev_out == NULL) + goto out; dev_put(dev_out); - dev_out = NULL; + dev_out = NULL; + } } -- 2.20.1