From df377be38725ced628251c1a3b954ef932a5586e Mon Sep 17 00:00:00 2001 From: Geliang Tang Date: Tue, 22 Jun 2021 12:25:20 -0700 Subject: [PATCH] mptcp: add deny_join_id0 in mptcp_options_received This patch added a new flag named deny_join_id0 in struct mptcp_options_received. Set it when MP_CAPABLE with the flag MPTCP_CAP_DENYJOIN_ID0 is received. Also add a new flag remote_deny_join_id0 in struct mptcp_pm_data. When the flag deny_join_id0 is set, set this remote_deny_join_id0 flag. In mptcp_pm_create_subflow_or_signal_addr, if the remote_deny_join_id0 flag is set, and the remote address id is zero, stop this connection. Suggested-by: Florian Westphal Acked-by: Paolo Abeni Signed-off-by: Geliang Tang Signed-off-by: Mat Martineau Signed-off-by: David S. Miller --- net/mptcp/options.c | 7 +++++++ net/mptcp/pm.c | 1 + net/mptcp/pm_netlink.c | 3 ++- net/mptcp/protocol.h | 4 +++- net/mptcp/subflow.c | 2 ++ 5 files changed, 15 insertions(+), 2 deletions(-) diff --git a/net/mptcp/options.c b/net/mptcp/options.c index 7a4b6d0bf3f6..a05270996613 100644 --- a/net/mptcp/options.c +++ b/net/mptcp/options.c @@ -83,6 +83,9 @@ static void mptcp_parse_option(const struct sk_buff *skb, if (flags & MPTCP_CAP_CHECKSUM_REQD) mp_opt->csum_reqd = 1; + if (flags & MPTCP_CAP_DENY_JOIN_ID0) + mp_opt->deny_join_id0 = 1; + mp_opt->mp_capable = 1; if (opsize >= TCPOLEN_MPTCP_MPC_SYNACK) { mp_opt->sndr_key = get_unaligned_be64(ptr); @@ -360,6 +363,7 @@ void mptcp_get_options(const struct sock *sk, mp_opt->mp_prio = 0; mp_opt->reset = 0; mp_opt->csum_reqd = READ_ONCE(msk->csum_enabled); + mp_opt->deny_join_id0 = 0; length = (th->doff * 4) - sizeof(struct tcphdr); ptr = (const unsigned char *)(th + 1); @@ -908,6 +912,9 @@ static bool check_fully_established(struct mptcp_sock *msk, struct sock *ssk, return false; } + if (mp_opt->deny_join_id0) + WRITE_ONCE(msk->pm.remote_deny_join_id0, true); + if (unlikely(!READ_ONCE(msk->pm.server_side))) pr_warn_once("bogus mpc option on established client sk"); mptcp_subflow_fully_established(subflow, mp_opt); diff --git a/net/mptcp/pm.c b/net/mptcp/pm.c index 9d00fa6d22e9..639271e09604 100644 --- a/net/mptcp/pm.c +++ b/net/mptcp/pm.c @@ -320,6 +320,7 @@ void mptcp_pm_data_init(struct mptcp_sock *msk) WRITE_ONCE(msk->pm.addr_signal, 0); WRITE_ONCE(msk->pm.accept_addr, false); WRITE_ONCE(msk->pm.accept_subflow, false); + WRITE_ONCE(msk->pm.remote_deny_join_id0, false); msk->pm.status = 0; spin_lock_init(&msk->pm.lock); diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c index d4732a4f223e..d2591ebf01d9 100644 --- a/net/mptcp/pm_netlink.c +++ b/net/mptcp/pm_netlink.c @@ -451,7 +451,8 @@ static void mptcp_pm_create_subflow_or_signal_addr(struct mptcp_sock *msk) /* check if should create a new subflow */ if (msk->pm.local_addr_used < local_addr_max && - msk->pm.subflows < subflows_max) { + msk->pm.subflows < subflows_max && + !READ_ONCE(msk->pm.remote_deny_join_id0)) { local = select_local_address(pernet, msk); if (local) { struct mptcp_addr_info remote = { 0 }; diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h index f2326f6074b9..f4eaa5f57e3f 100644 --- a/net/mptcp/protocol.h +++ b/net/mptcp/protocol.h @@ -138,7 +138,8 @@ struct mptcp_options_received { mp_prio : 1, echo : 1, csum_reqd : 1, - backup : 1; + backup : 1, + deny_join_id0 : 1; u32 token; u32 nonce; u64 thmac; @@ -193,6 +194,7 @@ struct mptcp_pm_data { bool work_pending; bool accept_addr; bool accept_subflow; + bool remote_deny_join_id0; u8 add_addr_signaled; u8 add_addr_accepted; u8 local_addr_used; diff --git a/net/mptcp/subflow.c b/net/mptcp/subflow.c index e9e8ce862218..d55f4ef736a5 100644 --- a/net/mptcp/subflow.c +++ b/net/mptcp/subflow.c @@ -408,6 +408,8 @@ static void subflow_finish_connect(struct sock *sk, const struct sk_buff *skb) if (mp_opt.csum_reqd) WRITE_ONCE(mptcp_sk(parent)->csum_enabled, true); + if (mp_opt.deny_join_id0) + WRITE_ONCE(mptcp_sk(parent)->pm.remote_deny_join_id0, true); subflow->mp_capable = 1; subflow->can_ack = 1; subflow->remote_key = mp_opt.sndr_key;