@PYTHON_SHEBANG@

"""

Upgrade script to enable authentication for CUPS-Get-Document in

default policy

"""

import os

import sys

from shutil import copy

def get_cupsd_conf():

    """

    Get all lines from cupsd.conf

    """

    if not os.path.exists('/etc/cups/cupsd.conf'):

        return None

    lines = []

    with open('/etc/cups/cupsd.conf', 'r') as conf:

        lines = conf.readlines()

    return lines

def get_default_policy(lines):

    """

    Get the default policy lines

    :param list lines: lines from cupsd.conf

    """

    default_policy = []

    in_policy = False

    for line in lines:

        if not in_policy and not line.lstrip().startswith('<Policy default>'):

            continue

        default_policy.append(line)

        if line.lstrip().startswith('</Policy>'):

            return default_policy

        in_policy = True

    return default_policy

def get_limit_with_document(lines):

    """

    Get <Limit> scope which defines CUPS-Get-Document operation

    :param list lines: Lines containing the default policy

    """

    limit = []

    in_limit = False

    for line in lines:

        if not in_limit and not line.lstrip().startswith('

            continue

        if (not in_limit and line.lstrip().startswith('

            not 'CUPS-Get-Document' in line.lstrip().split('#')[0][1:-1]):

            continue

        limit.append(line)

        if line.lstrip().startswith('</Limit>'):

            return limit

        in_limit = True

    return limit

def check_for_authtype(lines):

    """

    Check if <Limit> defining CUPS-Get-Document defines

    any authentication

    :param list lines: Lines of <Limit> scope which defines CUPS-Get-Document

    """

    for line in lines:

        if line.lstrip().startswith('AuthType'):

            return True

    return False

def migrate_cupsd_conf(lines):

    """

    Make changes to cupsd.conf contents to use authentication

    for CUPS-Get-Document

    :param list lines: Lines from cupsd.conf

    """

    new_lines = []

    in_policy = False

    create_document_limit = False

    for line in lines:

        if (in_policy and line.lstrip().startswith('

            not line.lstrip().startswith('<Limit CUPS-Get-Document>') and

            'CUPS-Get-Document' in line.lstrip().split('#')[0][1:-1]):

            line = line.replace(' CUPS-Get-Document', '')

            create_document_limit = True

        if in_policy and line.lstrip().startswith('</Policy>') and create_document_limit:

            new_lines.append('\n')

            new_lines.append((len(line) - len(line.lstrip()) + 2) * ' ' +

                             '# added during upgrade\n')

            new_lines.append((len(line) - len(line.lstrip()) + 2) * ' ' +

                             '<Limit CUPS-Get-Document>\n')

            new_lines.append((len(line) - len(line.lstrip()) + 4) * ' ' +

                             'AuthType Default\n')

            new_lines.append((len(line) - len(line.lstrip()) + 4) * ' ' +

                             'Require user @OWNER @SYSTEM\n')

            new_lines.append((len(line) - len(line.lstrip()) + 4) * ' ' +

                             'Order deny,allow\n')

            new_lines.append((len(line) - len(line.lstrip()) + 2) * ' ' +

                             '</Limit>\n')

            create_document_limit = False

        new_lines.append(line)

        if not in_policy:

            if line.lstrip().startswith('<Policy default>'):

                in_policy = True

            continue

        if line.lstrip().startswith('<Limit CUPS-Get-Document>'):

            new_lines.append((len(line) - len(line.lstrip()) + 2) * ' ' +

                             '# added during upgrade\n')

            new_lines.append((len(line) - len(line.lstrip()) + 2) * ' ' +

                             'AuthType Default\n')

            continue

        if line.lstrip().startswith('</Policy>'):

            in_policy = False

            continue

    return new_lines

def apply_changes(lines):

    """

    Backup the original file if there is no .rpmsave already and

    apply changes to the actual cupsd.conf

    :param list lines: New lines for cupsd.conf

    """

    if not os.path.exists('/etc/cups/cupsd.conf.rpmsave'):

        copy('/etc/cups/cupsd.conf', '/etc/cups/cupsd.conf.rpmsave')

    with open('/etc/cups/cupsd.conf', 'w') as conf:

        conf.writelines(lines)

content = get_cupsd_conf()

if content is None:

    sys.exit(1)

if check_for_authtype(get_limit_with_document(get_default_policy(content))):

    sys.exit(0)

new_content = migrate_cupsd_conf(content)

apply_changes(new_content)

sys.exit(0)