From d2f77960e5b03b2d373252b2ee150a4a14010f99 Mon Sep 17 00:00:00 2001 From: Geliang Tang Date: Tue, 22 Jun 2021 12:25:18 -0700 Subject: [PATCH] mptcp: add sysctl allow_join_initial_addr_port This patch added a new sysctl, named allow_join_initial_addr_port, to control whether allow peers to send join requests to the IP address and port number used by the initial subflow. Suggested-by: Florian Westphal Acked-by: Paolo Abeni Signed-off-by: Geliang Tang Signed-off-by: Mat Martineau Signed-off-by: David S. Miller --- Documentation/networking/mptcp-sysctl.rst | 13 +++++++++++++ net/mptcp/ctrl.c | 16 ++++++++++++++++ net/mptcp/protocol.h | 1 + 3 files changed, 30 insertions(+) diff --git a/Documentation/networking/mptcp-sysctl.rst b/Documentation/networking/mptcp-sysctl.rst index ee06fd782465..76d939e688b8 100644 --- a/Documentation/networking/mptcp-sysctl.rst +++ b/Documentation/networking/mptcp-sysctl.rst @@ -32,3 +32,16 @@ checksum_enabled - BOOLEAN per-namespace sysctl. Default: 0 + +allow_join_initial_addr_port - BOOLEAN + Allow peers to send join requests to the IP address and port number used + by the initial subflow if the value is 1. This controls a flag that is + sent to the peer at connection time, and whether such join requests are + accepted or denied. + + Joins to addresses advertised with ADD_ADDR are not affected by this + value. + + This is a per-namespace sysctl. + + Default: 1 diff --git a/net/mptcp/ctrl.c b/net/mptcp/ctrl.c index 6c2639bb9c19..7d738bd06f2c 100644 --- a/net/mptcp/ctrl.c +++ b/net/mptcp/ctrl.c @@ -24,6 +24,7 @@ struct mptcp_pernet { u8 mptcp_enabled; unsigned int add_addr_timeout; u8 checksum_enabled; + u8 allow_join_initial_addr_port; }; static struct mptcp_pernet *mptcp_get_pernet(struct net *net) @@ -46,11 +47,17 @@ int mptcp_is_checksum_enabled(struct net *net) return mptcp_get_pernet(net)->checksum_enabled; } +int mptcp_allow_join_id0(struct net *net) +{ + return mptcp_get_pernet(net)->allow_join_initial_addr_port; +} + static void mptcp_pernet_set_defaults(struct mptcp_pernet *pernet) { pernet->mptcp_enabled = 1; pernet->add_addr_timeout = TCP_RTO_MAX; pernet->checksum_enabled = 0; + pernet->allow_join_initial_addr_port = 1; } #ifdef CONFIG_SYSCTL @@ -80,6 +87,14 @@ static struct ctl_table mptcp_sysctl_table[] = { .extra1 = SYSCTL_ZERO, .extra2 = SYSCTL_ONE }, + { + .procname = "allow_join_initial_addr_port", + .maxlen = sizeof(u8), + .mode = 0644, + .proc_handler = proc_dou8vec_minmax, + .extra1 = SYSCTL_ZERO, + .extra2 = SYSCTL_ONE + }, {} }; @@ -98,6 +113,7 @@ static int mptcp_pernet_new_table(struct net *net, struct mptcp_pernet *pernet) table[0].data = &pernet->mptcp_enabled; table[1].data = &pernet->add_addr_timeout; table[2].data = &pernet->checksum_enabled; + table[3].data = &pernet->allow_join_initial_addr_port; hdr = register_net_sysctl(net, MPTCP_SYSCTL_PATH, table); if (!hdr) diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h index 160c2ab09f19..9aab5fb54716 100644 --- a/net/mptcp/protocol.h +++ b/net/mptcp/protocol.h @@ -540,6 +540,7 @@ static inline void mptcp_subflow_delegated_done(struct mptcp_subflow_context *su int mptcp_is_enabled(struct net *net); unsigned int mptcp_get_add_addr_timeout(struct net *net); int mptcp_is_checksum_enabled(struct net *net); +int mptcp_allow_join_id0(struct net *net); void mptcp_subflow_fully_established(struct mptcp_subflow_context *subflow, struct mptcp_options_received *mp_opt); bool mptcp_subflow_data_available(struct sock *sk); -- 2.25.1