acceptancetests/assess_log_forward.py

#!/usr/bin/env python
"""Test Juju's log forwarding feature.

Log forwarding allows a controller to forward syslog from all models of a
controller to a syslog host via TCP (using SSL).

"""

from __future__ import print_function

import argparse
import logging
import os
import re
import sys
import socket
import subprocess
from textwrap import dedent

from assess_model_migration import get_bootstrap_managers
import certificates
from jujucharm import local_charm_path
from utility import (
    add_basic_testing_arguments,
    configure_logging,
    get_unit_public_ip,
    JujuAssertionError,
    temp_dir,
)


__metaclass__ = type


log = logging.getLogger("assess_log_forward")


def assess_log_forward(bs_dummy, bs_rsyslog, upload_tools):
    """Ensure logs are forwarded after forwarding enabled after bootstrapping.

    Given 2 controllers set rsyslog and dummy:
      - setup rsyslog with secure details
      - Enable log forwarding on dummy
      - Ensure intial logs are present in the rsyslog sinks logs

    """
    with bs_rsyslog.booted_context(upload_tools):
        log.info('Bootstrapped rsyslog environment')
        rsyslog = bs_rsyslog.client
        rsyslog_details = deploy_rsyslog(rsyslog)

        update_client_config(bs_dummy.client, rsyslog_details)

        with bs_dummy.existing_booted_context(upload_tools):
            log.info('Bootstrapped dummy environment')
            dummy_client = bs_dummy.client

            unit_machine = 'rsyslog/0'
            remote_script_path = create_check_script_on_unit(
                rsyslog, unit_machine)

            ensure_enabling_log_forwarding_forwards_previous_messages(
                rsyslog, dummy_client, unit_machine, remote_script_path)
            ensure_multiple_models_forward_messages(
                rsyslog, dummy_client, unit_machine, remote_script_path)


def ensure_multiple_models_forward_messages(
        rsyslog, dummy, unit_machine, remote_check_path):
    """Assert that logs of multiple models are forwarded.

    :raises JujuAssertionError: If the expected message does not appear in the
      given timeframe.
    :raises JujuAssertionError: If the log message check fails in an unexpected
      way.
    """
    model1 = dummy.add_model('{}-{}'.format(dummy.env.environment, 'model1'))

    charm_path = local_charm_path(
        charm='dummy-source', juju_ver=model1.version)

    enable_log_forwarding(model1)

    model1.deploy(charm_path)
    model1.wait_for_started()

    model1_check_string = get_assert_regex(model1.get_model_uuid())

    check_remote_log_for_content(
        rsyslog, unit_machine, model1_check_string, remote_check_path)


def ensure_enabling_log_forwarding_forwards_previous_messages(
        rsyslog, dummy, unit_machine, remote_check_path):
    """Assert that mention of the sources logs appear in the sinks logging.

    Given a rsyslog sink and an output source assert that logging details from
    the source appear in the sinks logging.
    Attempt a check over a period of time (10 seconds).

    :raises JujuAssertionError: If the expected message does not appear in the
      given timeframe.
    :raises JujuAssertionError: If the log message check fails in an unexpected
      way.

    """
    uuid = dummy.get_controller_model_uuid()

    enable_log_forwarding(dummy)
    check_string = get_assert_regex(uuid)

    check_remote_log_for_content(
        rsyslog, unit_machine, check_string, remote_check_path)


def check_remote_log_for_content(
        remote_machine, unit, check_string, script_path):
    try:
        remote_machine.juju(
            'ssh',
            (
                unit,
                'sudo',
                'python',
                script_path,
                check_string,
                '/var/log/syslog'))
        log.info('Check script passed on target machine.')
    except subprocess.CalledProcessError:
        # This is where a failure happened
        raise JujuAssertionError('Forwarded log message never appeared.')


def create_check_script_on_unit(client, unit_machine):
    script_path = os.path.join(os.path.dirname(__file__), 'log_check.py')
    script_dest_path = os.path.join('/tmp', os.path.basename(script_path))
    client.juju(
        'scp',
        (script_path, '{}:{}'.format(unit_machine, script_dest_path)))
    return script_dest_path


def get_assert_regex(raw_uuid, message=None):
    """Create a regex string to check syslog file.

    If message is supplied it is expected to be escaped as needed (i.e. spaces)
    no further massaging will be done to the message string.

    """
    # Maybe over simplified removing the last 8 characters
    uuid = re.escape(raw_uuid)
    short_uuid = re.escape(raw_uuid[:-8])
    date_check = '[A-Z][a-z]{,2}\ +[0-9]+\ +[0-9]{1,2}:[0-9]{1,2}:[0-9]{1,2}'
    machine = 'machine-0.{}'.format(uuid)
    agent = 'jujud-machine-agent-{}'.format(short_uuid)
    message = message or '.*'

    return '"^{datecheck}\ {machine}\ {agent}\ {message}$"'.format(
        datecheck=date_check,
        machine=machine,
        agent=agent,
        message=message)


def enable_log_forwarding(client):
    client.set_env_option('logforward-enabled', 'true')
    client.get_controller_client().set_env_option('logforward-enabled', 'true')


def update_client_config(client, rsyslog_details):
    client.env.update_config({'logforward-enabled': False})
    client.env.update_config(rsyslog_details)


def deploy_rsyslog(client):
    """Deploy and setup the rsyslog charm on client.

    :returns: Configuration details needed: cert, ca, key and ip:port.

    """
    app_name = 'rsyslog'
    client.deploy('rsyslog', (app_name))
    client.wait_for_started()
    client.set_config(app_name, {'protocol': 'tcp'})
    client.juju('expose', app_name)

    return setup_tls_rsyslog(client, app_name)


def setup_tls_rsyslog(client, app_name):
    unit_machine = '{}/0'.format(app_name)

    ip_address = get_unit_public_ip(client, unit_machine)

    client.juju(
        'ssh',
        (unit_machine, 'sudo apt-get install rsyslog-gnutls'))

    with temp_dir() as config_dir:
        install_rsyslog_config(client, config_dir, unit_machine)
        rsyslog_details = install_certificates(
            client, config_dir, ip_address, unit_machine)

    # restart rsyslog to take into affect all changes
    client.juju('ssh', (unit_machine, 'sudo', 'service', 'rsyslog', 'restart'))

    return rsyslog_details


def install_certificates(client, config_dir, ip_address, unit_machine):
    cert, key = certificates.create_certificate(config_dir, ip_address)

    # Write contents to file to scp across
    ca_file = os.path.join(config_dir, 'ca.pem')
    with open(ca_file, 'wt') as f:
        f.write(certificates.ca_pem_contents)

    scp_command = (
        '--', cert, key, ca_file, '{unit}:/home/ubuntu/'.format(
            unit=unit_machine))
    client.juju('scp', scp_command)

    return _get_rsyslog_details(cert, key, ip_address)


def _get_rsyslog_details(cert_file, key_file, ip_address):
    with open(cert_file, 'rt') as f:
        cert_contents = f.read()
    with open(key_file, 'rt') as f:
        key_contents = f.read()

    return {
        'syslog-host': '{}'.format(add_port_to_ip(ip_address, '10514')),
        'syslog-ca-cert': certificates.ca_pem_contents,
        'syslog-client-cert': cert_contents,
        'syslog-client-key': key_contents
    }


def add_port_to_ip(ip_address, port):
    """Return an ipv4/ipv6 address with port added to `ip_address`."""
    try:
        socket.inet_aton(ip_address)
        return '{}:{}'.format(ip_address, port)
    except socket.error:
        try:
            socket.inet_pton(socket.AF_INET6, ip_address)
            return '[{}]:{}'.format(ip_address, port)
        except socket.error:
            pass
    raise ValueError(
        'IP Address "{}" is neither an ipv4 or ipv6 address.'.format(
            ip_address))


def install_rsyslog_config(client, config_dir, unit_machine):
    config = write_rsyslog_config_file(config_dir)
    client.juju('scp', (config, '{unit}:/tmp'.format(unit=unit_machine)))
    client.juju(
        'ssh',
        (unit_machine, 'sudo', 'mv', '/tmp/{}'.format(
            os.path.basename(config)), '/etc/rsyslog.d/'))


def write_rsyslog_config_file(tmp_dir):
    """Write rsyslog config file to `tmp_dir`/10-securelogging.conf."""
    config = dedent("""\
    # make gtls driver the default
    $DefaultNetstreamDriver gtls

    # certificate files
    $DefaultNetstreamDriverCAFile /home/ubuntu/ca.pem
    $DefaultNetstreamDriverCertFile /home/ubuntu/cert.pem
    $DefaultNetstreamDriverKeyFile /home/ubuntu/key.pem

    $ModLoad imtcp # load TCP listener
    $InputTCPServerStreamDriverAuthMode x509/name
    $InputTCPServerStreamDriverPermittedPeer anyServer
    $InputTCPServerStreamDriverMode 1 # run driver in TLS-only mode
    $InputTCPServerRun 10514 # port 10514
    """)
    config_path = os.path.join(tmp_dir, '10-securelogging.conf')
    with open(config_path, 'wt') as f:
        f.write(config)
    return config_path


def parse_args(argv):
    """Parse all arguments."""
    parser = argparse.ArgumentParser(
        description="Test log forwarding of logs.")
    # Don't use existing as this test modifies controller settings.
    add_basic_testing_arguments(parser, existing=False)
    return parser.parse_args(argv)


def main(argv=None):
    args = parse_args(argv)
    configure_logging(args.verbose)
    bs_dummy, bs_rsyslog = get_bootstrap_managers(args)
    assess_log_forward(bs_dummy, bs_rsyslog, args.upload_tools)
    return 0


if __name__ == '__main__':
    sys.exit(main())