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 <fw@strlen.de>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/mptcp/options.c b/net/mptcp/options.c
index 7a4b6d0bf3f60b7f2dd1cce1616daa1338b9089b..a05270996613c32f801a1d544953850d6db4ff1a 100644 (file)
--- 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 9d00fa6d22e9115204ad63c953a2a0d37e0ef9fe..639271e09604a947c9f83cad73ec19624ead82fa 100644 (file)
--- 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 d4732a4f223e39e454801f7c23a51c048f3b79fe..d2591ebf01d9378e1825ea46cf529f4cc133eb5c 100644 (file)
--- 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 f2326f6074b940a874ca367db93cfa1005438d68..f4eaa5f57e3f0d350ef4b67811d8fa9de8d35e98 100644 (file)
--- 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 e9e8ce862218fbf738788e834f10528a56e96218..d55f4ef736a5068244f779a7162ebeec0a287c36 100644 (file)
--- 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;