Kernel/linux
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git synced 2025-01-17 18:36:00 +00:00
Code Issues Actions Packages Projects Releases Wiki Activity

mptcp: full fully established support after ADD_ADDR

Browse Source 
If directly after an MP_CAPABLE 3WHS, the client receives an ADD_ADDR
with HMAC from the server, it is enough to switch to a "fully
established" mode because it has received more MPTCP options.

It was then OK to enable the "fully_established" flag on the MPTCP
socket. Still, best to check if the ADD_ADDR looks valid by looking if
it contains an HMAC (no 'echo' bit). If an ADD_ADDR echo is received
while we are not in "fully established" mode, it is strange and then
we should not switch to this mode now.

But that is not enough. On one hand, the path-manager has be notified
the state has changed. On the other hand, the "fully_established" flag
on the subflow socket should be turned on as well not to re-send the
MP_CAPABLE 3rd ACK content with the next ACK.

Fixes: 84dfe3677a6f ("mptcp: send out dedicated ADD_ADDR packet")
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Matthieu Baerts 2021-08-18 16:42:37 -07:00 committed by David S. Miller
parent a0eea5f10e
commit 67b12f792d
1 changed files with 3 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
net/mptcp/options.c
View File

@ -885,20 +885,16 @@ static bool check_fully_established(struct mptcp_sock *msk, struct sock *ssk,
return subflow->mp_capable;
}
if (mp_opt->dss && mp_opt->use_ack) {
if ((mp_opt->dss && mp_opt->use_ack) ||
(mp_opt->add_addr && !mp_opt->echo)) {
/* subflows are fully established as soon as we get any
* additional ack.
* additional ack, including ADD_ADDR.
*/
subflow->fully_established = 1;
WRITE_ONCE(msk->fully_established, true);
goto fully_established;
}
if (mp_opt->add_addr) {
WRITE_ONCE(msk->fully_established, true);
return true;
}
/* If the first established packet does not contain MP_CAPABLE + data
* then fallback to TCP. Fallback scenarios requires a reset for
* MP_JOIN subflows.