diff options
| author | Matthieu Baerts (NGI0) <matttbe@kernel.org> | 2024-09-09 22:09:23 +0200 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2024-09-11 15:57:50 -0700 |
| commit | 27069e7cb3d1cea9377069266acf19b9cc5ad0ae (patch) | |
| tree | b2b59e53ce7fee633efeb019b4903cba0b649ac8 /net/mptcp/mib.h | |
| parent | 6982826fe5e53ef115836de7dd397bd970030937 (diff) | |
mptcp: disable active MPTCP in case of blackhole
An MPTCP firewall blackhole can be detected if the following SYN
retransmission after a fallback to "plain" TCP is accepted.
In case of blackhole, a similar technique to the one in place with TFO
is now used: MPTCP can be disabled for a certain period of time, 1h by
default. This time period will grow exponentially when more blackhole
issues get detected right after MPTCP is re-enabled and will reset to
the initial value when the blackhole issue goes away.
The blackhole period can be modified thanks to a new sysctl knob:
blackhole_timeout. Two new MIB counters help understanding what's
happening:
- 'Blackhole', incremented when a blackhole is detected.
- 'MPCapableSYNTXDisabled', incremented when an MPTCP connection
directly falls back to TCP during the blackhole period.
Because the technique is inspired by the one used by TFO, an important
part of the new code is similar to what can find in tcp_fastopen.c, with
some adaptations to the MPTCP case.
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/57
Signed-off-by: Matthieu Baerts (NGI0) <matttbe@kernel.org>
Link: https://patch.msgid.link/20240909-net-next-mptcp-fallback-x-mpc-v1-3-da7ebb4cd2a3@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'net/mptcp/mib.h')
| -rw-r--r-- | net/mptcp/mib.h | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/net/mptcp/mib.h b/net/mptcp/mib.h index 062775700b63..c8ffe18a8722 100644 --- a/net/mptcp/mib.h +++ b/net/mptcp/mib.h @@ -11,6 +11,7 @@ enum linux_mptcp_mib_field { MPTCP_MIB_MPCAPABLEPASSIVEFALLBACK,/* Server-side fallback during 3-way handshake */ MPTCP_MIB_MPCAPABLEACTIVEFALLBACK, /* Client-side fallback during 3-way handshake */ MPTCP_MIB_MPCAPABLEACTIVEDROP, /* Client-side fallback due to a MPC drop */ + MPTCP_MIB_MPCAPABLEACTIVEDISABLED, /* Client-side disabled due to past issues */ MPTCP_MIB_TOKENFALLBACKINIT, /* Could not init/allocate token */ MPTCP_MIB_RETRANSSEGS, /* Segments retransmitted at the MPTCP-level */ MPTCP_MIB_JOINNOTOKEN, /* Received MP_JOIN but the token was not found */ @@ -75,6 +76,7 @@ enum linux_mptcp_mib_field { */ MPTCP_MIB_RCVWNDCONFLICT, /* Conflict with while updating msk rcv wnd */ MPTCP_MIB_CURRESTAB, /* Current established MPTCP connections */ + MPTCP_MIB_BLACKHOLE, /* A blackhole has been detected */ __MPTCP_MIB_MAX }; |