diff options
| author | Johannes Berg <johannes.berg@intel.com> | 2016-02-04 13:31:20 +0100 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2016-02-11 04:27:36 -0500 |
| commit | 7a02bf892d8f1e5298af1676f001bee410509d80 (patch) | |
| tree | dcdd03f7fdedaf5c1ff5363415b68afe6ac57374 /net | |
| parent | abbc30436d39dfed8ebfca338d253f211ac7b094 (diff) | |
ipv6: add option to drop unsolicited neighbor advertisements
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>
Diffstat (limited to 'net')
| -rw-r--r-- | net/ipv6/addrconf.c | 8 | ||||
| -rw-r--r-- | net/ipv6/ndisc.c | 9 |
2 files changed, 17 insertions, 0 deletions
diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c index 23e325f39f8e..ac0ba9e4e06b 100644 --- a/net/ipv6/addrconf.c +++ b/net/ipv6/addrconf.c @@ -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) @@ -5793,6 +5794,13 @@ static struct addrconf_sysctl_table .proc_handler = proc_dointvec, }, { + .procname = "drop_unsolicited_na", + .data = &ipv6_devconf.drop_unsolicited_na, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = proc_dointvec, + }, + { /* sentinel */ } }, diff --git a/net/ipv6/ndisc.c b/net/ipv6/ndisc.c index 84afb9a77278..c245895a3d41 100644 --- a/net/ipv6/ndisc.c +++ b/net/ipv6/ndisc.c @@ -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; |