Signed-off-by: Arne Schwabe <a...@rfc2549.org> --- Changes.rst | 9 +++ doc/man-sections/script-options.rst | 3 + sample/sample-scripts/totpauth.py | 107 ++++++++++++++++++++++++++++ 3 files changed, 119 insertions(+) create mode 100755 sample/sample-scripts/totpauth.py
diff --git a/Changes.rst b/Changes.rst index 188bd8ab..d64c6d83 100644 --- a/Changes.rst +++ b/Changes.rst @@ -19,6 +19,15 @@ Pending auth support for plugins and scripts be used to parse a client response to a ``CR_TEXT`` two factor challenge. See ``sample/sample-scripts/totpauth.py`` for an example. +<<<<<<< HEAD +======= + +Deprecated features +------------------- +``inetd`` has been removed + This was a very limited and not-well-tested way to run OpenVPN, on TCP + and TAP mode only. +>>>>>>> 239e8cfd (Add example script demonstrating TOTP via auth-pending) Overview of changes in 2.5 diff --git a/doc/man-sections/script-options.rst b/doc/man-sections/script-options.rst index 1d7118ae..05815020 100644 --- a/doc/man-sections/script-options.rst +++ b/doc/man-sections/script-options.rst @@ -147,6 +147,9 @@ SCRIPT HOOKS :code:`auth_control_file or further defer it. See ``--auth-user-pass-verify`` for details. + For a sample script that implement TOTP (RFC 6238) based two-factor + authentication, see :code:`sample-scripts/totp.py`. + --client-connect cmd Run command ``cmd`` on client connection. diff --git a/sample/sample-scripts/totpauth.py b/sample/sample-scripts/totpauth.py new file mode 100755 index 00000000..95ac3529 --- /dev/null +++ b/sample/sample-scripts/totpauth.py @@ -0,0 +1,107 @@ +#! /usr/bin/python3 +# Copyright (c) 2020 OpenVPN Inc <sa...@openvpn.net> +# +# Permission is hereby granted, free of charge, to any person obtaining a copy +# of this software and associated documentation files (the "Software"), to deal +# in the Software without restriction, including without limitation the rights +# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell +# copies of the Software, and to permit persons to whom the Software is +# furnished to do so, subject to the following conditions: +# +# The above copyright notice and this permission notice shall be included in all +# copies or substantial portions of the Software. +# +# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR +# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, +# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE +# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER +# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, +# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE +# SOFTWARE. + +import sys +import os +from base64 import standard_b64decode + +import pyotp + +import pprint + +# Example script demonstrating how to use the auth-pending API in +# OpenVPN. This script is provided under MIT license to allow easy +# modification for other purposes. +# +# To use this script add the following lines in the openvpn config + +# client-crresponse /path/to/totpauth.py +# auth-user-pass-verify /path/to/totpauth.py via-file +# auth-user-pass-optional +# auth-gen-token + +# Note that this script does NOT verify username/password +# It is only meant for querying additional 2FA when certificates are +# used to authenticate + +secrets = {"styx": "OS6JDNRK2BNUPQVX", + "apate": "IXWEMP7SK2QWSHTG"} + + +def main(): + # Get common name and script type from environment + script_type = os.environ['script_type'] + cn = os.environ['common_name'] + + if script_type == 'user-pass-verify': + # signal text based challenge response + + if cn in secrets: + extra = "CR_TEXT:E,R:Please enter your TOTP code!" + write_auth_pending(300, 'crtext', extra) + + # Signal authentication being deferred + sys.exit(2) + else: + # For unkown CN we report failure. Change to 0 + # to allow CNs without secret to auth without 2FA + sys.exit(1) + + elif script_type == 'client-crresponse': + response = None + + # Read the crresponse from the argument file + # and convert it into text. A failure because of bad user + # input (e.g. invalid base64) will make the script throw + # an error and make OpenVPN return AUTH_FAILED + with open(sys.argv[1], 'r') as crinput: + response = crinput.read() + response = standard_b64decode(response) + response = response.decode().strip() + + if cn not in secrets: + write_auth_control(1) + return + + totp = pyotp.TOTP(secrets[cn]) + + # Check if the code is valid (and also allow code +/-1) + if totp.verify(response, valid_window=1): + write_auth_control(1) + else: + write_auth_control(0) + else: + print(f"Unknown script type {script_type}") + sys.exit(1) + + +def write_auth_control(status): + with open(os.environ['auth_control_file'], 'w') as auth_control: + auth_control.write("%d" % status) + + +def write_auth_pending(timeout, method, extra): + with open(os.environ['auth_pending_file'], 'w') as auth_pending: + auth_pending.write("%d\n%s\n%s" % (timeout, method, extra)) + + +if __name__ == '__main__': + main() -- 2.30.0 _______________________________________________ Openvpn-devel mailing list Openvpn-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/openvpn-devel