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/msg.h | 10 ++++++++++ net/tipc/node.h | 12 +++++++----- net/tipc/socket.c | 5 +++++ 3 files changed, 22 insertions(+), 5 deletions(-) diff --git a/net/tipc/msg.h b/net/tipc/msg.h index a4e944d59394..cd64d7b2a0fe 100644 --- a/net/tipc/msg.h +++ b/net/tipc/msg.h @@ -216,6 +216,16 @@ static inline void msg_set_non_seq(struct tipc_msg *m, u32 n) msg_set_bits(m, 0, 20, 1, n); } +static inline int msg_is_syn(struct tipc_msg *m) +{ + return msg_bits(m, 0, 17, 1); +} + +static inline void msg_set_syn(struct tipc_msg *m, u32 d) +{ + msg_set_bits(m, 0, 17, 1, d); +} + static inline int msg_dest_droppable(struct tipc_msg *m) { return msg_bits(m, 0, 19, 1); diff --git a/net/tipc/node.h b/net/tipc/node.h index 48b3298a248d..03f5efb62cfb 100644 --- a/net/tipc/node.h +++ b/net/tipc/node.h @@ -45,6 +45,7 @@ /* Optional capabilities supported by this code version */ enum { + TIPC_SYN_BIT = (1), TIPC_BCAST_SYNCH = (1 << 1), TIPC_BCAST_STATE_NACK = (1 << 2), TIPC_BLOCK_FLOWCTL = (1 << 3), @@ -53,11 +54,12 @@ enum { TIPC_LINK_PROTO_SEQNO = (1 << 6) }; -#define TIPC_NODE_CAPABILITIES (TIPC_BCAST_SYNCH | \ - TIPC_BCAST_STATE_NACK | \ - TIPC_BCAST_RCAST | \ - TIPC_BLOCK_FLOWCTL | \ - TIPC_NODE_ID128 | \ +#define TIPC_NODE_CAPABILITIES (TIPC_SYN_BIT | \ + TIPC_BCAST_SYNCH | \ + TIPC_BCAST_STATE_NACK | \ + TIPC_BCAST_RCAST | \ + TIPC_BLOCK_FLOWCTL | \ + TIPC_NODE_ID128 | \ TIPC_LINK_PROTO_SEQNO) #define INVALID_BEARER_ID -1 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 v1.2.3-55-g7522