When we decide we need to rekey, we enqueue any further packets until we've sent
our SSH2_MSG_NEWKEYS message, after which we dequeue these packets and send them
to the other side. This enqueueing is done based on ssh_packet_in_rekey checking
the session flags and whether DH handshake state is marked as finished.
However, the handshake state is not reset to DH_STATE_FINISHED until the other
side has sent us their new keys. This leaves a gap between sending our new keys
and receiving the other side's new keys where we would still decide to enqueue a
packet.
These enqueued packets will not be dequeued as we've already sent our new keys.
Once we've received the other side's new keys, we'll go back to a finished
handshake and we will send out our caller's new data, skipping however much data
we've enqueued.
Fix this by changing ssh_packet_in_rekey to return false once we've sent our new
keys.
Signed-off-by: Carlos Martín Nieto <carlosmn@github.com>
Reviewed-by: Jakub Jelen <jjelen@redhat.com>
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