#!/usr/bin/python

import sys
from optparse import OptionParser

import pysss
import SSSDConfig
import getpass

def parse_options():
    parser = OptionParser()
    parser.set_description("sss_obfuscate converts a given password into \
                            human-unreadable format and places it into \
                            appropriate domain section of the SSSD config \
                            file. The password can be passed in by stdin, \
                            specified on the command-line or entered \
                            interactively")
    parser.add_option("-s", "--stdin", action="store_true",
                      dest="stdin", default=False,
                      help="Read the password from stdin.")
    parser.add_option("-d", "--domain",
                      dest="domain", default=None,
                      help="The domain to use the password in (mandatory)",
                      metavar="DOMNAME")
    parser.add_option("-f", "--file",
                      dest="filename", default=None,
                      help="Set input file to FILE (default: Use system default, usually /etc/sssd/sssd.conf)",
                      metavar="FILE")
    (options, args) = parser.parse_args()

    return options, args

def main():
    options, args = parse_options()
    if not options:
        print >> sys.stderr, "Cannot parse options"
        return 1

    if not options.domain:
        print >> sys.stderr, "No domain specified"
        return 1

    if not options.stdin:
        try:
            pprompt = lambda: (getpass.getpass("Enter password: "), getpass.getpass("Re-enter password: "))
            p1, p2 = pprompt()

            #Work around bug in Python 2.6
            if '\x03' in p1 or '\x03' in p2:
                raise KeyboardInterrupt

            while p1 != p2:
                print('Passwords do not match. Try again')
                p1, p2 = pprompt()

                #Work around bug in Python 2.6
                if '\x03' in p1 or '\x03' in p2:
                    raise KeyboardInterrupt
            password = p1

        except EOFError:
            print >> sys.stderr, '\nUnexpected end-of-file. Password change aborted'
            return 1
        except KeyboardInterrupt:
            return 1

    else:
        try:
            password = sys.stdin.read()
        except KeyboardInterrupt:
            return 1

    # Obfuscate the password
    obfobj = pysss.password()
    obfpwd = obfobj.encrypt(password, obfobj.AES_256)

    # Save the obfuscated password into the domain
    try:
        sssdconfig = SSSDConfig.SSSDConfig()
    except IOError:
        print "Cannot read internal configuration files."
        return 1
    try:
        sssdconfig.import_config(options.filename)
    except IOError:
        print "Permissions error reading config file"
        return 1

    try:
        domain = sssdconfig.get_domain(options.domain)
    except SSSDConfig.NoDomainError:
        print "No such domain %s" % options.domain
        return 1

    try:
        domain.set_option('ldap_default_authtok_type', 'obfuscated_password')
        domain.set_option('ldap_default_authtok', obfpwd)
    except SSSDConfig.NoOptionError:
        print "The domain %s does not seem to support the required options" % \
              options.domain
        return 1


    sssdconfig.save_domain(domain)
    try:
        sssdconfig.write()
    except IOError:
        # File could not be written
        print >> sys.stderr, "Could not write to config file. Check that " \
                             "you have the appropriate permissions to edit " \
                             "this file."
        return 1

    return 0

if __name__ == "__main__":
    ret = main()
    sys.exit(ret)
