[IPV6]: Disallow RH0 by default.
A security issue is emerging. Disallow Routing Header Type 0 by default
as we have been doing for IPv4.
Note: We allow RH2 by default because it is harmless.
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/Documentation/networking/ip-sysctl.txt b/Documentation/networking/ip-sysctl.txt
index d3aae1f..702d1d8d 100644
--- a/Documentation/networking/ip-sysctl.txt
+++ b/Documentation/networking/ip-sysctl.txt
@@ -851,6 +851,15 @@
Functional default: enabled if local forwarding is disabled.
disabled if local forwarding is enabled.
+accept_source_route - INTEGER
+ Accept source routing (routing extension header).
+
+ > 0: Accept routing header.
+ = 0: Accept only routing header type 2.
+ < 0: Do not accept routing header.
+
+ Default: 0
+
autoconf - BOOLEAN
Autoconfigure addresses using Prefix Information in Router
Advertisements.
diff --git a/include/linux/ipv6.h b/include/linux/ipv6.h
index f824113..713eb5e 100644
--- a/include/linux/ipv6.h
+++ b/include/linux/ipv6.h
@@ -177,6 +177,7 @@
#endif
#endif
__s32 proxy_ndp;
+ __s32 accept_source_route;
void *sysctl;
};
@@ -205,6 +206,8 @@
DEVCONF_RTR_PROBE_INTERVAL,
DEVCONF_ACCEPT_RA_RT_INFO_MAX_PLEN,
DEVCONF_PROXY_NDP,
+ __DEVCONF_OPTIMISTIC_DAD,
+ DEVCONF_ACCEPT_SOURCE_ROUTE,
DEVCONF_MAX
};
diff --git a/include/linux/sysctl.h b/include/linux/sysctl.h
index 2c5fb38..9a8970b 100644
--- a/include/linux/sysctl.h
+++ b/include/linux/sysctl.h
@@ -580,6 +580,7 @@
NET_IPV6_RTR_PROBE_INTERVAL=21,
NET_IPV6_ACCEPT_RA_RT_INFO_MAX_PLEN=22,
NET_IPV6_PROXY_NDP=23,
+ NET_IPV6_ACCEPT_SOURCE_ROUTE=25,
__NET_IPV6_MAX
};
diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index 7552663..452a82c 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -172,6 +172,7 @@
#endif
#endif
.proxy_ndp = 0,
+ .accept_source_route = 0, /* we do not accept RH0 by default. */
};
static struct ipv6_devconf ipv6_devconf_dflt __read_mostly = {
@@ -203,6 +204,7 @@
#endif
#endif
.proxy_ndp = 0,
+ .accept_source_route = 0, /* we do not accept RH0 by default. */
};
/* IPv6 Wildcard Address and Loopback Address defined by RFC2553 */
@@ -3356,6 +3358,7 @@
#endif
#endif
array[DEVCONF_PROXY_NDP] = cnf->proxy_ndp;
+ array[DEVCONF_ACCEPT_SOURCE_ROUTE] = cnf->accept_source_route;
}
static inline size_t inet6_if_nlmsg_size(void)
@@ -3884,6 +3887,14 @@
.proc_handler = &proc_dointvec,
},
{
+ .ctl_name = NET_IPV6_ACCEPT_SOURCE_ROUTE,
+ .procname = "accept_source_route",
+ .data = &ipv6_devconf.accept_source_route,
+ .maxlen = sizeof(int),
+ .mode = 0644,
+ .proc_handler = &proc_dointvec,
+ },
+ {
.ctl_name = 0, /* sentinel */
}
},
diff --git a/net/ipv6/exthdrs.c b/net/ipv6/exthdrs.c
index 28e0c65..6ed6a8c 100644
--- a/net/ipv6/exthdrs.c
+++ b/net/ipv6/exthdrs.c
@@ -362,10 +362,27 @@
struct inet6_skb_parm *opt = IP6CB(skb);
struct in6_addr *addr = NULL;
struct in6_addr daddr;
+ struct inet6_dev *idev;
int n, i;
-
struct ipv6_rt_hdr *hdr;
struct rt0_hdr *rthdr;
+ int accept_source_route = ipv6_devconf.accept_source_route;
+
+ if (accept_source_route < 0 ||
+ ((idev = in6_dev_get(skb->dev)) == NULL)) {
+ kfree_skb(skb);
+ return -1;
+ }
+ if (idev->cnf.accept_source_route < 0) {
+ in6_dev_put(idev);
+ kfree_skb(skb);
+ return -1;
+ }
+
+ if (accept_source_route > idev->cnf.accept_source_route)
+ accept_source_route = idev->cnf.accept_source_route;
+
+ in6_dev_put(idev);
if (!pskb_may_pull(skb, (skb->h.raw-skb->data)+8) ||
!pskb_may_pull(skb, (skb->h.raw-skb->data)+((skb->h.raw[1]+1)<<3))) {
@@ -377,6 +394,22 @@
hdr = (struct ipv6_rt_hdr *) skb->h.raw;
+ switch (hdr->type) {
+#ifdef CONFIG_IPV6_MIP6
+ break;
+#endif
+ case IPV6_SRCRT_TYPE_0:
+ if (accept_source_route <= 0)
+ break;
+ kfree_skb(skb);
+ return -1;
+ default:
+ IP6_INC_STATS_BH(ip6_dst_idev(skb->dst),
+ IPSTATS_MIB_INHDRERRORS);
+ icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, (&hdr->type) - skb->nh.raw);
+ return -1;
+ }
+
if (ipv6_addr_is_multicast(&skb->nh.ipv6h->daddr) ||
skb->pkt_type != PACKET_HOST) {
IP6_INC_STATS_BH(ip6_dst_idev(skb->dst),
@@ -434,11 +467,6 @@
}
break;
#endif
- default:
- IP6_INC_STATS_BH(ip6_dst_idev(skb->dst),
- IPSTATS_MIB_INHDRERRORS);
- icmpv6_param_prob(skb, ICMPV6_HDR_FIELD, (&hdr->type) - skb->nh.raw);
- return -1;
}
/*