diff options
| -rw-r--r-- | Documentation/networking/ip-sysctl.txt | 5 | ||||
| -rw-r--r-- | include/linux/inetdevice.h | 2 | ||||
| -rw-r--r-- | net/ipv4/arp.c | 3 | ||||
| -rw-r--r-- | net/ipv4/devinet.c | 5 | ||||
| -rw-r--r-- | net/ipv4/route.c | 30 |
5 files changed, 34 insertions, 11 deletions
diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt index 6f896b94abd..99d0e0504d6 100644 --- a/Documentation/networking/ip-sysctl.txt +++ b/Documentation/networking/ip-sysctl.txt @@ -862,6 +862,11 @@ accept_local - BOOLEAN local interfaces over the wire and have them accepted properly. default FALSE +route_localnet - BOOLEAN + Do not consider loopback addresses as martian source or destination + while routing. This enables the use of 127/8 for local routing purposes. + default FALSE + rp_filter - INTEGER 0 - No source validation. 1 - Strict mode as defined in RFC3704 Strict Reverse Path diff --git a/include/linux/inetdevice.h b/include/linux/inetdevice.h index 597f4a9f324..67f9ddacb70 100644 --- a/include/linux/inetdevice.h +++ b/include/linux/inetdevice.h @@ -38,6 +38,7 @@ enum IPV4_DEVCONF_ACCEPT_LOCAL, IPV4_DEVCONF_SRC_VMARK, IPV4_DEVCONF_PROXY_ARP_PVLAN, + IPV4_DEVCONF_ROUTE_LOCALNET, __IPV4_DEVCONF_MAX }; @@ -131,6 +132,7 @@ static inline void ipv4_devconf_setall(struct in_device *in_dev) #define IN_DEV_PROMOTE_SECONDARIES(in_dev) \ IN_DEV_ORCONF((in_dev), \ PROMOTE_SECONDARIES) +#define IN_DEV_ROUTE_LOCALNET(in_dev) IN_DEV_ORCONF(in_dev, ROUTE_LOCALNET) #define IN_DEV_RX_REDIRECTS(in_dev) \ ((IN_DEV_FORWARD(in_dev) && \ diff --git a/net/ipv4/arp.c b/net/ipv4/arp.c index cda37be02f8..2e560f0c757 100644 --- a/net/ipv4/arp.c +++ b/net/ipv4/arp.c @@ -790,7 +790,8 @@ static int arp_process(struct sk_buff *skb) * Check for bad requests for 127.x.x.x and requests for multicast * addresses. If this is one such, delete it. */ - if (ipv4_is_loopback(tip) || ipv4_is_multicast(tip)) + if (ipv4_is_multicast(tip) || + (!IN_DEV_ROUTE_LOCALNET(in_dev) && ipv4_is_loopback(tip))) goto out; /* diff --git a/net/ipv4/devinet.c b/net/ipv4/devinet.c index 10e15a144e9..44bf82e3aef 100644 --- a/net/ipv4/devinet.c +++ b/net/ipv4/devinet.c @@ -1500,7 +1500,8 @@ static int devinet_conf_proc(ctl_table *ctl, int write, if (cnf == net->ipv4.devconf_dflt) devinet_copy_dflt_conf(net, i); - if (i == IPV4_DEVCONF_ACCEPT_LOCAL - 1) + if (i == IPV4_DEVCONF_ACCEPT_LOCAL - 1 || + i == IPV4_DEVCONF_ROUTE_LOCALNET - 1) if ((new_value == 0) && (old_value != 0)) rt_cache_flush(net, 0); } @@ -1617,6 +1618,8 @@ static struct devinet_sysctl_table { "force_igmp_version"), DEVINET_SYSCTL_FLUSHING_ENTRY(PROMOTE_SECONDARIES, "promote_secondaries"), + DEVINET_SYSCTL_FLUSHING_ENTRY(ROUTE_LOCALNET, + "route_localnet"), }, }; diff --git a/net/ipv4/route.c b/net/ipv4/route.c index 842510d5045..655506af47c 100644 --- a/net/ipv4/route.c +++ b/net/ipv4/route.c @@ -1960,9 +1960,13 @@ static int ip_route_input_mc(struct sk_buff *skb, __be32 daddr, __be32 saddr, return -EINVAL; if (ipv4_is_multicast(saddr) || ipv4_is_lbcast(saddr) || - ipv4_is_loopback(saddr) || skb->protocol != htons(ETH_P_IP)) + skb->protocol != htons(ETH_P_IP)) goto e_inval; + if (likely(!IN_DEV_ROUTE_LOCALNET(in_dev))) + if (ipv4_is_loopback(saddr)) + goto e_inval; + if (ipv4_is_zeronet(saddr)) { if (!ipv4_is_local_multicast(daddr)) goto e_inval; @@ -2203,8 +2207,7 @@ static int ip_route_input_slow(struct sk_buff *skb, __be32 daddr, __be32 saddr, by fib_lookup. */ - if (ipv4_is_multicast(saddr) || ipv4_is_lbcast(saddr) || - ipv4_is_loopback(saddr)) + if (ipv4_is_multicast(saddr) || ipv4_is_lbcast(saddr)) goto martian_source; if (ipv4_is_lbcast(daddr) || (saddr == 0 && daddr == 0)) @@ -2216,9 +2219,17 @@ static int ip_route_input_slow(struct sk_buff *skb, __be32 daddr, __be32 saddr, if (ipv4_is_zeronet(saddr)) goto martian_source; - if (ipv4_is_zeronet(daddr) || ipv4_is_loopback(daddr)) + if (ipv4_is_zeronet(daddr)) goto martian_destination; + if (likely(!IN_DEV_ROUTE_LOCALNET(in_dev))) { + if (ipv4_is_loopback(daddr)) + goto martian_destination; + + if (ipv4_is_loopback(saddr)) + goto martian_source; + } + /* * Now we are ready to route packet. */ @@ -2457,9 +2468,14 @@ static struct rtable *__mkroute_output(const struct fib_result *res, u16 type = res->type; struct rtable *rth; - if (ipv4_is_loopback(fl4->saddr) && !(dev_out->flags & IFF_LOOPBACK)) + in_dev = __in_dev_get_rcu(dev_out); + if (!in_dev) return ERR_PTR(-EINVAL); + if (likely(!IN_DEV_ROUTE_LOCALNET(in_dev))) + if (ipv4_is_loopback(fl4->saddr) && !(dev_out->flags & IFF_LOOPBACK)) + return ERR_PTR(-EINVAL); + if (ipv4_is_lbcast(fl4->daddr)) type = RTN_BROADCAST; else if (ipv4_is_multicast(fl4->daddr)) @@ -2470,10 +2486,6 @@ static struct rtable *__mkroute_output(const struct fib_result *res, if (dev_out->flags & IFF_LOOPBACK) flags |= RTCF_LOCAL; - in_dev = __in_dev_get_rcu(dev_out); - if (!in_dev) - return ERR_PTR(-EINVAL); - if (type == RTN_BROADCAST) { flags |= RTCF_BROADCAST | RTCF_LOCAL; fi = NULL; |