xiaomi-sm8450/android_kernel_xiaomi_sm8450
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

ipv6: add option to drop unsolicited neighbor advertisements

Browse Source 
In certain 802.11 wireless deployments, there will be NA proxies
that use knowledge of the network to correctly answer requests.
To prevent unsolicitd advertisements on the shared medium from
being a problem, on such deployments wireless needs to drop them.

Enable this by providing an option called "drop_unsolicited_na".

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Johannes Berg
2016-02-04 13:31:20 +01:00
committed by David S. Miller
parent abbc30436d
commit 7a02bf892d
5 changed files with 26 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

8
net/ipv6/addrconf.c
View File

@@ -4712,6 +4712,7 @@ static inline void ipv6_store_devconf(struct ipv6_devconf *cnf,
/* we omit DEVCONF_STABLE_SECRET for now */
array[DEVCONF_USE_OIF_ADDRS_ONLY] = cnf->use_oif_addrs_only;
array[DEVCONF_DROP_UNICAST_IN_L2_MULTICAST] = cnf->drop_unicast_in_l2_multicast;
array[DEVCONF_DROP_UNSOLICITED_NA] = cnf->drop_unsolicited_na;
}
static inline size_t inet6_ifla6_size(void)
@@ -5792,6 +5793,13 @@ static struct addrconf_sysctl_table
.mode = 0644,
.proc_handler = proc_dointvec,
},
{
.procname = "drop_unsolicited_na",
.data = &ipv6_devconf.drop_unsolicited_na,
.maxlen = sizeof(int),
.mode = 0644,
.proc_handler = proc_dointvec,
},
{
/* sentinel */
}

9
net/ipv6/ndisc.c
View File

@@ -883,6 +883,7 @@ static void ndisc_recv_na(struct sk_buff *skb)
offsetof(struct nd_msg, opt));
struct ndisc_options ndopts;
struct net_device *dev = skb->dev;
struct inet6_dev *idev = __in6_dev_get(dev);
struct inet6_ifaddr *ifp;
struct neighbour *neigh;
@@ -902,6 +903,14 @@ static void ndisc_recv_na(struct sk_buff *skb)
return;
}
/* For some 802.11 wireless deployments (and possibly other networks),
* there will be a NA proxy and unsolicitd packets are attacks
* and thus should not be accepted.
*/
if (!msg->icmph.icmp6_solicited && idev &&
idev->cnf.drop_unsolicited_na)
return;
if (!ndisc_parse_options(msg->opt, ndoptlen, &ndopts)) {
ND_PRINTK(2, warn, "NS: invalid ND option\n");
return;