From 6b102db50cdde3ba2f78631ed21222edf3a5fb51 Mon Sep 17 00:00:00 2001 From: David Ahern Date: Mon, 30 Dec 2019 14:14:29 -0800 Subject: 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 Signed-off-by: David S. Miller --- net/ipv6/tcp_ipv6.c | 20 +++++++++++++++++++- 1 file changed, 19 insertions(+), 1 deletion(-) (limited to 'net/ipv6') diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index 71ad7d89be0f..95e4e1e95db2 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -578,10 +578,28 @@ static int tcp_v6_parse_md5_keys(struct sock *sk, int optname, prefixlen = ipv6_addr_v4mapped(&sin6->sin6_addr) ? 32 : 128; } + 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; + } + if (!cmd.tcpm_keylen) { if (ipv6_addr_v4mapped(&sin6->sin6_addr)) return tcp_md5_do_del(sk, (union tcp_md5_addr *)&sin6->sin6_addr.s6_addr32[3], - AF_INET, prefixlen, l3index); + AF_INET, prefixlen, + l3index); return tcp_md5_do_del(sk, (union tcp_md5_addr *)&sin6->sin6_addr, AF_INET6, prefixlen, l3index); } -- cgit v1.2.3-59-g8ed1b