diff mbox series

[v5,mptcp-next,4/5] mptcp: add deny_join_id0 in mptcp_options_received

Message ID c9966a080be92cc508bfdeece2085cfaca7dbe2a.1620469774.git.geliangtang@gmail.com
State Superseded, archived
Delegated to: Mat Martineau
Headers show
Series add MP_CAPABLE 'C' flag | expand

Commit Message

Geliang Tang May 8, 2021, 10:33 a.m. UTC
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, use the first received ADD_ADDR address as the remote address to
connect.

Suggested-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Geliang Tang <geliangtang@gmail.com>
---
 net/mptcp/options.c    |  6 ++++++
 net/mptcp/pm.c         |  1 +
 net/mptcp/pm_netlink.c | 12 +++++++++++-
 net/mptcp/protocol.h   |  4 +++-
 net/mptcp/subflow.c    |  2 ++
 5 files changed, 23 insertions(+), 2 deletions(-)
diff mbox series

Patch

diff --git a/net/mptcp/options.c b/net/mptcp/options.c
index 441ec25e117d..b9188c53e58f 100644
--- a/net/mptcp/options.c
+++ b/net/mptcp/options.c
@@ -87,6 +87,9 @@  static void mptcp_parse_option(const struct sock *sk,
 		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);
@@ -363,6 +366,7 @@  void mptcp_get_options(const struct sock *sk,
 	mp_opt->mp_prio = 0;
 	mp_opt->reset = 0;
 	mp_opt->csum_reqd = 0;
+	mp_opt->deny_join_id0 = 0;
 
 	length = (th->doff * 4) - sizeof(struct tcphdr);
 	ptr = (const unsigned char *)(th + 1);
@@ -1055,6 +1059,8 @@  void mptcp_incoming_options(struct sock *sk, struct sk_buff *skb)
 	}
 
 	mptcp_get_options(sk, skb, &mp_opt);
+	if (mp_opt.deny_join_id0)
+		WRITE_ONCE(msk->pm.remote_deny_join_id0, true);
 	if (!check_fully_established(msk, sk, subflow, skb, &mp_opt))
 		return;
 
diff --git a/net/mptcp/pm.c b/net/mptcp/pm.c
index 9456fe17b6a3..23a309f641aa 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 47a515af2b0a..dddd7c5613fa 100644
--- a/net/mptcp/pm_netlink.c
+++ b/net/mptcp/pm_netlink.c
@@ -456,10 +456,20 @@  static void mptcp_pm_create_subflow_or_signal_addr(struct mptcp_sock *msk)
 		if (local) {
 			struct mptcp_addr_info remote = { 0 };
 
+			remote_address((struct sock_common *)sk, &remote);
+			if (READ_ONCE(msk->pm.remote_deny_join_id0)) {
+				struct mptcp_pm_add_entry *entry;
+
+				entry = list_first_entry_or_null(&msk->pm.add_list,
+								 typeof(*entry), list);
+				if (!entry)
+					return;
+
+				remote = entry->addr;
+			}
 			msk->pm.local_addr_used++;
 			msk->pm.subflows++;
 			check_work_pending(msk);
-			remote_address((struct sock_common *)sk, &remote);
 			spin_unlock_bh(&msk->pm.lock);
 			__mptcp_subflow_connect(sk, &local->addr, &remote,
 						local->flags, local->ifindex);
diff --git a/net/mptcp/protocol.h b/net/mptcp/protocol.h
index d19deee01896..5b2e72cf8e06 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;
@@ -194,6 +195,7 @@  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 249a66ad54dc..bb4bf31e73cf 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;