path: root/net/ipv4/tcp_ipv4.c
diff options
authorDavid Ahern <dsahern@gmail.com>2019-12-30 14:14:29 -0800
committerDavid S. Miller <davem@davemloft.net>2020-01-02 15:51:22 -0800
commit6b102db50cdde3ba2f78631ed21222edf3a5fb51 (patch)
tree81bd56771479c7ce34ce765f5e5fcaff74f00c36 /net/ipv4/tcp_ipv4.c
parenttcp: Add l3index to tcp_md5sig_key and md5 functions (diff)
net: Add device index to tcp_md5sig
Add support for userspace to specify a device index to limit the scope of an entry via the TCP_MD5SIG_EXT setsockopt. The existing __tcpm_pad is renamed to tcpm_ifindex and the new field is only checked if the new TCP_MD5SIG_FLAG_IFINDEX is set in tcpm_flags. For now, the device index must point to an L3 master device (e.g., VRF). The API and error handling are setup to allow the constraint to be relaxed in the future to any device index. Signed-off-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to '')
1 files changed, 18 insertions, 0 deletions
diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index 30b3f19d6301..4adac9c75343 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -1196,6 +1196,24 @@ static int tcp_v4_parse_md5_keys(struct sock *sk, int optname,
return -EINVAL;
+ if (optname == TCP_MD5SIG_EXT &&
+ cmd.tcpm_flags & TCP_MD5SIG_FLAG_IFINDEX) {
+ struct net_device *dev;
+ rcu_read_lock();
+ dev = dev_get_by_index_rcu(sock_net(sk), cmd.tcpm_ifindex);
+ if (dev && netif_is_l3_master(dev))
+ l3index = dev->ifindex;
+ rcu_read_unlock();
+ /* ok to reference set/not set outside of rcu;
+ * right now device MUST be an L3 master
+ */
+ if (!dev || !l3index)
+ return -EINVAL;
+ }
addr = (union tcp_md5_addr *)&sin->sin_addr.s_addr;
if (!cmd.tcpm_keylen)