dev-python/paramiko: bump to 2.4.2

Also, disable the server feature by default for security reasons. It can
be re-enabled with the 'server' USE flag, which is going to be
hard-masked.

Bug: https://bugs.gentoo.org/666619
Package-Manager: Portage-2.3.50, Repoman-2.3.11
Signed-off-by: Virgil Dupras <vdupras@gentoo.org>

dev-python/paramiko/files/paramiko-2.4.2-disable-server.patch

@@ -0,0 +1,46 @@
+diff --git a/paramiko/transport.py b/paramiko/transport.py
+index f72eebaf..ec7a1445 100644
+--- a/paramiko/transport.py
++++ b/paramiko/transport.py
+@@ -110,6 +110,8 @@ from paramiko.ssh_exception import (
+ from paramiko.util import retry_on_signal, ClosingContextManager, clamp_value
+ 
+ 
++SERVER_DISABLED_BY_GENTOO = True
++
+ # for thread cleanup
+ _active_threads = []
+ 
+@@ -633,6 +635,8 @@ class Transport(threading.Thread, ClosingContextManager):
+             `.SSHException` -- if negotiation fails (and no ``event`` was
+             passed in)
+         """
++        if SERVER_DISABLED_BY_GENTOO:
++            raise Exception("Disabled by Gentoo for security reasons. Enable with 'server' USE flag")
+         if server is None:
+             server = ServerInterface()
+         self.server_mode = True
+diff --git a/tests/conftest.py b/tests/conftest.py
+index 2b509c5c..bb23ac74 100644
+--- a/tests/conftest.py
++++ b/tests/conftest.py
+@@ -4,7 +4,7 @@ import shutil
+ import threading
+ 
+ import pytest
+-from paramiko import RSAKey, SFTPServer, SFTP, Transport
++from paramiko import RSAKey, SFTPServer, SFTP, Transport, transport
+ 
+ from .loop import LoopSocket
+ from .stub_sftp import StubServer, StubSFTPServer
+@@ -15,6 +15,10 @@ from .util import _support
+ # 'nicer'.
+ 
+ 
++# We need the server component for testing
++transport.SERVER_DISABLED_BY_GENTOO = False
++
++
+ # Perform logging by default; pytest will capture and thus hide it normally,
+ # presenting it on error/failure. (But also allow turning it off when doing
+ # very pinpoint debugging - e.g. using breakpoints, so you don't want output