From 25b9221b959483f17c2964d0922869e16caa86b5 Mon Sep 17 00:00:00 2001 From: Jon Maloy Date: Fri, 28 Sep 2018 20:23:21 +0200 Subject: tipc: add SYN bit to connection setup messages Messages intended for intitating a connection are currently indistinguishable from regular datagram messages. The TIPC protocol specification defines bit 17 in word 0 as a SYN bit to allow sanity check of such messages in the listening socket, but this has so far never been implemented. We do that in this commit. Acked-by: Ying Xue Signed-off-by: Jon Maloy Signed-off-by: David S. Miller --- net/tipc/socket.c | 5 +++++ 1 file changed, 5 insertions(+) (limited to 'net/tipc/socket.c') diff --git a/net/tipc/socket.c b/net/tipc/socket.c index 094cfdc1e2b6..89d6dc0f456d 100644 --- a/net/tipc/socket.c +++ b/net/tipc/socket.c @@ -1319,6 +1319,7 @@ static int __tipc_sendmsg(struct socket *sock, struct msghdr *m, size_t dlen) tsk->conn_type = dest->addr.name.name.type; tsk->conn_instance = dest->addr.name.name.instance; } + msg_set_syn(hdr, 1); } seq = &dest->addr.nameseq; @@ -1478,6 +1479,7 @@ static void tipc_sk_finish_conn(struct tipc_sock *tsk, u32 peer_port, struct net *net = sock_net(sk); struct tipc_msg *msg = &tsk->phdr; + msg_set_syn(msg, 0); msg_set_destnode(msg, peer_node); msg_set_destport(msg, peer_port); msg_set_type(msg, TIPC_CONN_MSG); @@ -2006,6 +2008,9 @@ static bool tipc_sk_filter_connect(struct tipc_sock *tsk, struct sk_buff *skb) return false; case TIPC_LISTEN: /* Accept only SYN message */ + if (!msg_is_syn(hdr) && + tipc_node_get_capabilities(net, onode) & TIPC_SYN_BIT) + return false; if (!con_msg && !err) return true; return false; -- cgit v1.2.3