This is an automated email from the git hooks/post-receive script. x2go pushed a commit to branch release/4.0.1.x in repository x2goserver. commit 9297f6b1c94192ef307a6fcdaad817624fab2fc3 Author: Mihai Moldovan <ionic@ionic.de> Date: Thu Jan 4 05:38:00 2018 +0100 x2goserver/lib: new script x2gogetrandomport, contains the port randomization (or pseudo-randomization) features that are part of x2gostartagent, but need to be accessible by other scripts as well. --- debian/changelog | 3 + x2goserver/lib/x2gogetrandomport | 120 +++++++++++++++++++++++++++++++++++++++ 2 files changed, 123 insertions(+) diff --git a/debian/changelog b/debian/changelog index 6696e7f..0befe04 100644 --- a/debian/changelog +++ b/debian/changelog @@ -38,6 +38,9 @@ x2goserver (4.0.1.23-0x2go1) UNRELEASED; urgency=medium pattern substitutions gracefully. Remove them. - x2goserver/lib: new script x2gogetfreeport, consists of duplicated functionality in x2gostartagent. + - x2goserver/lib: new script x2gogetrandomport, contains the port + randomization (or pseudo-randomization) features that are part of + x2gostartagent, but need to be accessible by other scripts as well. * x2goserver.spec: - RPMify x2goserver-xsession description. - Remove qt4 stuff, we're not using the framework here. diff --git a/x2goserver/lib/x2gogetrandomport b/x2goserver/lib/x2gogetrandomport new file mode 100755 index 0000000..c269270 --- /dev/null +++ b/x2goserver/lib/x2gogetrandomport @@ -0,0 +1,120 @@ +#!/bin/bash + +# Copyright (C) 2017-2018 X2Go Project - https://wiki.x2go.org +# +# This program is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation; either version 2 of the License, or +# (at your option) any later version. +# +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with this program; if not, write to the +# Free Software Foundation, Inc., +# 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA. + +typeset x2go_lib_path="$(x2gopath "libexec")" + +"${x2go_lib_path}/x2gosyslog" "${0}" "debug" "$(basename "${0}") called with options: ${*}" + +# rnowotny, <rnowotny@rotek.at> +# Patch for SSH_PORT, to not use the same SSH port on each server, which is a +# problem if you want to connect to different servers at the same time with +# the windows client. +# Original problem report: https://www.mail-archive.com/x2go-user@lists.berlios.de/msg00547.html +# Currently implementation is based on the submitted patch, but differs heavily. + +# Gets the outward-facing server IPv4 address. +# Does not take any parameters. +# Outputs the default outgoing IPv4 address. +# Returns 0 on success, otherwise non-0. +get_server_ip_address() { + # The provided IP address should be outside of any local network. + # We are only interested in how the kernel would try to reach the + # non-local IP address specified here. It is not actually contacted + # in any way. + typeset ip_output="$(ip route get 8.8.8.8)" + + # Remove newlines. + ip_output="${ip_output//$'\n'}" + + # Fetch source address. + typeset src_address="$(grep -oe 'src[[:space:]]\{1,\}\(\([[:digit:]]\{1,3\}\.\)\{3\}[[:digit:]]\{1,3\}\)' <<< "${ip_output}" | sed -e 's/src[[:space:]]\{1,\}//')" + + if [[ -n "${src_address}" ]]; then + printf '%s\n' "${src_address}" + return "0" + fi + + return "1" +} + +# Get some purely random port. +# Does not take any parameters. +# Outputs a random port value in range [30000, 62767]. +# Returns 0. +get_pure_random_port() { + typeset -i unix_timestamp="$(date "+%s")" + + # Seed ${RANDOM}. This should probably be changed some time before 2106. + # Or maybe not. + RANDOM="${unix_timestamp}" + + typeset -i random_port="$((30000 + RANDOM))" + printf '%d\n' "${random_port}" + + return "0" +} + +# Gets a pseudo-random port based on the machine's +# outgoing IP address. +# Does not take any parameters. +# Outputs a host-based pseudo-random port value. +# Returns 0 on success, otherwise non-0. +get_host_based_random_port() { + "${x2go_lib_path}/x2gosyslog" "${0}" "debug" "host-based SSH port initialization requested." + typeset ip_address='' + typeset -i ret_port='0' + typeset -i ret='1' + + if ip_address="$(get_server_ip_address)"; then + typeset -i ip_address_last_octet="${ip_address##*.}" + ret_port="$((30000 + (ip_address_last_octet * 128)))" + + printf '%d\n' "${ret_port}" + fi + + return "${ret}" +} + + +# Refer to x2goserver.conf. +typeset -i randomize_ssh_port="1" +typeset randomize_ssh_port_config_value='' + +randomize_ssh_port_config_value="$("${x2go_lib_path}/x2goqueryconfig" "x2goagent" "port_randomization")" + +# Failures or incorrect values are implicitly caught by the default value. +[[ "${randomize_ssh_port_config_value}" = "host-based" ]] && randomize_ssh_port='0' + +if [ "${randomize_ssh_port}" = "1" ]; then + "${x2go_lib_path}/x2gosyslog" "${0}" "debug" "Full SSH port randomization requested." + get_random_port +else + "${x2go_lib_path}/x2gosyslog" "${0}" "debug" "host-based SSH port initialization requested." + + if ! get_host_based_random_port; then + "${x2go_lib_path}/x2gosyslog" "${0}" "warning" "IP-based SSH port initialization requested, but failed to fetch primary address." + "${x2go_lib_path}/x2gosyslog" "${0}" "warning" "Falling back to randomization." + get_random_port + fi +fi + +# No explicit return value, will use the last command's return value. +# Make sure that the last command executed exits with the +# return value you want to pass through! +exit -- Alioth's /home/x2go-admin/maintenancescripts/git/hooks/post-receive-email on /srv/git/code.x2go.org/x2goserver.git