Re: [gentoo-portage-dev] [PATCH v2] Support escaping network-sandbox through SOCKSv5 proxy

[Zac Medico <zmedico@gentoo.org>]

On 01/25/2015 06:00 AM, Michał Górny wrote:
> diff --git a/bin/socks5-server.py b/bin/socks5-server.py
> new file mode 100644
> index 0000000..c079018
> --- /dev/null
> +++ b/bin/socks5-server.py
> @@ -0,0 +1,218 @@
> +#!/usr/bin/env python
> +# SOCKSv5 proxy server for network-sandbox
> +# Copyright 2015 Gentoo Foundation
> +# Distributed under the terms of the GNU General Public License v2
> +
> +import asyncore
> +import errno
> +import socket
> +import struct
> +import sys
> +
> +
> +class ProxyConnection(asyncore.dispatcher_with_send):
> +	_addr = None
> +	_connected = False
> +	_family = socket.AF_INET
> +	_proxy_conn = None
> +
> +	def __init__(self, proxy_conn):
> +		self._proxy_conn = proxy_conn
> +		asyncore.dispatcher_with_send.__init__(self)
> +		self.create_socket(self._family, socket.SOCK_STREAM)
> +
> +	def start_connection(self, host, port):
> +		try:
> +			self.connect((host, port))
> +		except:
> +			self.handle_error()

This except handler should at least allow SystemExit and
KeyboardInterrupt to raise.

> diff --git a/pym/portage/package/ebuild/_config/special_env_vars.py b/pym/portage/package/ebuild/_config/special_env_vars.py
> index 6bb3c95..905d5e7 100644
> --- a/pym/portage/package/ebuild/_config/special_env_vars.py
> +++ b/pym/portage/package/ebuild/_config/special_env_vars.py
> @@ -71,7 +71,7 @@ environ_whitelist += [
>  	"PORTAGE_PYM_PATH", "PORTAGE_PYTHON",
>  	"PORTAGE_PYTHONPATH", "PORTAGE_QUIET",
>  	"PORTAGE_REPO_NAME", "PORTAGE_REPOSITORIES", "PORTAGE_RESTRICT",
> -	"PORTAGE_SIGPIPE_STATUS",
> +	"PORTAGE_SIGPIPE_STATUS", "PORTAGE_SOCKS5_PROXY",
>  	"PORTAGE_TMPDIR", "PORTAGE_UPDATE_ENV", "PORTAGE_USERNAME",
>  	"PORTAGE_VERBOSE", "PORTAGE_WORKDIR_MODE", "PORTAGE_XATTR_EXCLUDE",
>  	"PORTDIR", "PORTDIR_OVERLAY", "PREROOTPATH",

The DISTCC_SOCKS_PROXY variable should also be added to the whitelist.

Other than these 2 minor issues, the patch looks to me. I guess there's
no point in using portage's event loop instead of asyncore, since we
want the proxy to drop privileges, and therefore it can't run in the
main portage process.
-- 
Thanks,
Zac