postfix-policyd-spf-python 1.2-1 / usr / bin / policyd-spf

#! /usr/bin/python3
# -*- coding: utf-8 -*-
#
#  Check SPF results and provide recommended action back to Postfix.
#
#  Tumgreyspf source
#  Copyright © 2004-2005, Sean Reifschneider, tummy.com, ltd.
#  <jafo@tummy.com>
#
#  pypolicyd-spf
#  Copyright © 2007-12, Scott Kitterman <scott@kitterman.com>
'''
   Licensed under the Apache License, Version 2.0 (the "License");
   you may not use this file except in compliance with the License.
   You may obtain a copy of the License at

       http://www.apache.org/licenses/LICENSE-2.0

   Unless required by applicable law or agreed to in writing, software
   distributed under the License is distributed on an "AS IS" BASIS,
   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   See the License for the specific language governing permissions and
   limitations under the License.
'''

__version__ = "1.2: JULY 25, 2013"

testing = True

import syslog
import os
import sys
import string
import re
import socket
import spf
import policydspfsupp
try:
    import ipaddress
except ImportError:
    import ipaddr as ipaddress
try:
    import authres
except:
    pass # authres not needed in default configuration.

syslog.openlog(os.path.basename(sys.argv[0]), syslog.LOG_PID, syslog.LOG_MAIL)
policydspfsupp._setExceptHook()

#############################################
def _cidrmatch(ip, netwrk):
    """Match connect IP against a CIDR network of other IP addresses."""

    try:
        address = ipaddress.ip_address(ip)
    except AttributeError:
        address = ipaddress.IPAddress(ip)
    try:
        network = ipaddress.IPv4Network(netwrk)
    except ipaddress.AddressValueError:
        network = ipaddress.IPv6Network(netwrk)
    return network.__contains__(address)

def _get_rdns_lookup(ip):
    try:
        address = ipaddress.ip_address(ip)
    except AttributeError:
        address = ipaddress.IPAddress(ip)
    if isinstance(address, ipaddress.IPv4Address):
        components = address.exploded.split('.')
        return '.'.join(components[::-1]) + '.in-addr.arpa'    
    else:
        components = address.exploded.split(':')
        return '.'.join('.'.join(list(quad)) for quad in components)[::-1] + '.ip6.arpa'
#############################################
def _get_resultcodes(configData, scope):
    # Parse config options for SPF results to correct Posftix actions
    actions = {'defer':[], 'reject':[], 'prepend':[]}
    local = {'local_helo': False, 'local_mfrom': False}
    unused_results = ['Pass', 'None', 'Neutral', 'Softfail', 'Fail', 'Temperror', 'Permerror'] 
    helo_policy = ''
    mfrom_policy = ''
    reject_domain_list = []
    sender = data.get('sender')
    helo = data.get('helo_name')
    if configData.get('Reject_Not_Pass_Domains'):
        reject_domains = (str(configData.get('Reject_Not_Pass_Domains')))
        reject_domain_list = reject_domains.split(',')
        if "@" in sender:
            sender_domain = sender.split('@', 1)[1]
        else:
            sender_domain = ''

    if scope == 'helo':
        helo_policy = configData.get('HELO_reject')
        if spf.domainmatch(reject_domain_list, helo):
            helo_policy = 'SPF_Not_Pass'
            local['local_helo'] = True
        if helo_policy == 'SPF_Not_Pass':
            try:
                unused_results.remove('Fail')
                actions['reject'].append('Fail')
                unused_results.remove('Softfail')
                actions['reject'].append('Softfail')
                unused_results.remove('Neutral')
                actions['reject'].append('Neutral')
            except:
                if debugLevel >= 2: syslog.syslog('Configuration File parsing error: HELO_reject')
        elif helo_policy == 'Softfail':
            try:
                unused_results.remove('Fail')
                actions['reject'].append('Fail')
                unused_results.remove('Softfail')
                actions['reject'].append('Softfail')

            except:
                if debugLevel >= 2: syslog.syslog('Configuration File parsing error: HELO_reject')
        elif helo_policy == 'Fail' or helo_policy == 'Null':
            try:
                unused_results.remove('Fail')
                actions['reject'].append('Fail')
            except:
                if debugLevel >= 2: syslog.syslog('Configuration File parsing error: HELO_reject')
    if scope == 'mfrom':
        mfrom_policy = configData.get('Mail_From_reject')
        if "@" in sender:
            sender_domain = sender.split('@', 1)[1]
        else:
            sender_domain = ''
        if spf.domainmatch(reject_domain_list, sender_domain):
            mfrom_policy = 'SPF_Not_Pass'
            local['local_mfrom'] = True
        if mfrom_policy == 'SPF_Not_Pass':
            try:
                unused_results.remove('Fail')
                actions['reject'].append('Fail')
                unused_results.remove('Softfail')
                actions['reject'].append('Softfail')
                unused_results.remove('Neutral')
                actions['reject'].append('Neutral')
            except:
                if debugLevel >= 2: syslog.syslog('Configuration File parsing error: Mail_From_reject')
        elif mfrom_policy == 'Softfail':
            try:
                unused_results.remove('Fail')
                actions['reject'].append('Fail')
                unused_results.remove('Softfail')
                actions['reject'].append('Softfail')

            except:
                if debugLevel >= 2: syslog.syslog('Configuration File parsing error: Mail_From_reject')
        elif mfrom_policy == 'Fail':
            try:
                unused_results.remove('Fail')
                actions['reject'].append('Fail')
            except:
                if debugLevel >= 2: syslog.syslog('Configuration File parsing error: Mail_From_reject')

    if (helo_policy == 'False' and scope == 'helo') or (mfrom_policy == 'False' and scope == 'mfrom'):
        for result in unused_results:
            actions['prepend'].append(result)
        return(actions, local)
    if configData.get('TempError_Defer') == 'True':
        actions['defer'].append('Temperror')
        unused_results.remove('Temperror')
    if configData.get('PermError_reject') == 'True':
        actions['reject'].append('Permerror')
        unused_results.remove('Permerror')
    for result in unused_results:
        actions['prepend'].append(result)
    return(actions, local)
#############################################
def _spfbypass(data, check_type, configData):
    if configData.get(check_type):
        if configData.get('Prospective'):
            ip = configData.get('Prospective')
        else:
            ip = data.get('client_address')
        bypass_list = (str(configData.get(check_type)))
        bypass_list_list = bypass_list.split(',')
        if check_type == 'skip_addresses' or check_type == 'Whitelist':
            for skip_network in bypass_list_list:
                try:
                    if _cidrmatch(ip, skip_network):
                        if check_type == 'skip_addresses':
                            comment = 'SPF check N/A for local connections - '
                        else:
                            comment = 'SPF skipped for whitelisted relay - '
                        if 'SPF' in configData.get('Header_Type'):
                            Header = ('X-Comment: ' + comment + 'client-ip=%s; helo=%s; envelope-from=%s; receiver=%s '
                                % ( data.get('client_address', '<UNKNOWN>'),
                                    data.get('helo_name', '<UNKNOWN>'),
                                    data.get('sender', '<UNKNOWN>'),
                                    data.get('recipient', '<UNKNOWN>'),
                                    ))
                        elif 'AR' in configData.get('Header_Type'):
                            try:
                                Header = str(authres.AuthenticationResultsHeader(authserv_id = configData.get('Authserv_Id'),
                                    results = [authres.NoneAuthenticationResult(comment = \
                                    '{0} client-ip={1}; helo={2}; envelope-from={3}; receiver={4}'.format(comment, data.get('client_address', '<UNKNOWN>'),\
                                        data.get('helo_name', '<UNKNOWN>'), data.get('sender', '<UNKNOWN>'), data.get('recipient', '<UNKNOWN>'))
                                        )]))
                            except TypeError as x:
                                if str(x).startswith('sequence item 2'):
                                    syslog.syslog(syslog.LOG_ERR, 'Authserv_Id not set for authentication results header - invalid configuration.')
                                    raise SyntaxError('Authserv_Id not set for authentication results header - invalid configuration.')
                        if debugLevel >= 3: syslog.syslog(Header)
                        return (True, Header)
                except ValueError as msg:
                    Message = 'ERROR: {0} in {1} not IP network.  Message: {2}. Aborting whitelist processing.'.format(skip_network, check_type, msg)
                    if debugLevel: syslog.syslog(Message)
                    return (False, 'None')
            return (False, 'None')
        elif check_type == 'Domain_Whitelist':
            for domain in bypass_list_list:
                res = spf.check2(ip, domain, domain)
                domain_res = [res[0], res[1]]
                domain_res[0] = domain_res[0].lower()
                domain_res[0] = domain_res[0].capitalize()
                if domain_res[0] == 'Pass':
                    comment = 'SPF skipped for whitelisted relay domain - '
                    if 'SPF' in configData.get('Header_Type'):
                        Header = ('X-Comment: ' + comment + 'client-ip=%s; helo=%s; envelope-from=%s; receiver=%s '
                            % ( data.get('client_address', '<UNKNOWN>'),
                                data.get('helo_name', '<UNKNOWN>'),
                                data.get('sender', '<UNKNOWN>'),
                                data.get('recipient', '<UNKNOWN>'),
                                ))
                    elif 'AR' in configData.get('Header_Type'):
                        try:
                            Header = str(authres.AuthenticationResultsHeader(authserv_id = configData.get('Authserv_Id'),
                                results = [authres.NoneAuthenticationResult(comment = \
                                '{0} client-ip={1}; helo={2}; envelope-from={3}; receiver={4}'.format(comment, data.get('client_address', '<UNKNOWN>'),\
                                    data.get('helo_name', '<UNKNOWN>'), data.get('sender', '<UNKNOWN>'), data.get('recipient', '<UNKNOWN>'))
                                    )]))
                        except TypeError as x:
                            if str(x).startswith('sequence item 2'):
                                syslog.syslog(syslog.LOG_ERR, 'Authserv_Id not set for authentication results header - invalid configuration.')
                                raise SyntaxError('Authserv_Id not set for authentication results header - invalid configuration.')

                    if debugLevel >= 3: syslog.syslog(Header)
                    return (True, Header)
            return (False, 'None')
        elif check_type == 'Domain_Whitelist_PTR':
            if debugLevel >= 4: syslog.syslog ("PTR Domain Whitelist enabled.")
            try:
                # Try a reverse DNS lookup first and try and match against the domain list that way
                rDNSResults = spf.DNSLookup (_get_rdns_lookup(ip), 'ptr')
                if (len (rDNSResults) > 0):
                    rDNSName = rDNSResults [0][1]
                else:
                    # Reverse lookup didn't find any records, so don't continue with the check
                    rDNSName = None
            except spf.TempError as e:
                # DNS timeout - continue with the base SPF check.
                rDNSName = None
            if (rDNSName is not None):
                for domain in bypass_list_list:
                    if (rDNSName.endswith (domain)):
                        comment = 'SPF skipped for PTR whitelisted relay domain - '
                        if 'SPF' in configData.get('Header_Type'):
                            Header = ('X-Comment: ' + comment + 'client-ip=%s; helo=%s; envelope-from=%s; receiver=%s '
                                % ( data.get('client_address', '<UNKNOWN>'),
                                    data.get('helo_name', '<UNKNOWN>'),
                                    data.get('sender', '<UNKNOWN>'),
                                    data.get('recipient', '<UNKNOWN>'),
                                    ))
                        elif 'AR' in configData.get('Header_Type'):
                            try:
                                Header = str(authres.AuthenticationResultsHeader(authserv_id = configData.get('Authserv_Id'),
                                    results = [authres.NoneAuthenticationResult(comment = \
                                    '{0} client-ip={1}; helo={2}; envelope-from={3}; receiver={4}'.format(comment, data.get('client_address', '<UNKNOWN>'),\
                                        data.get('helo_name', '<UNKNOWN>'), data.get('sender', '<UNKNOWN>'), data.get('recipient', '<UNKNOWN>'))
                                        )]))
                            except TypeError as x:
                                if str(x).startswith('sequence item 2'):
                                    syslog.syslog(syslog.LOG_ERR, 'Authserv_Id not set for authentication results header - invalid configuration.')
                                    raise SyntaxError('Authserv_Id not set for authentication results header - invalid configuration.')

                        if debugLevel >= 3: syslog.syslog(Header)
                        return (True, Header)
            return (False, 'None')
#############################################
def _spfcheck(data, instance_dict, configData, peruser):  #{{{1
    debugLevel = configData.get('debugLevel', 1)
    if configData.get('Prospective'):
        ip = configData.get('Prospective')
    else:
        ip = data.get('client_address')
    if ip == None:
        if debugLevel >= 2: syslog.syslog('spfcheck: No client address, exiting')
        return(( None, None, instance_dict ))
    instance = data.get('instance')
    # The following if is only needed for testing.  Postfix 
    # will always provide instance.
    if not instance:
        import random
        instance = str(int(random.random()*100000))
    # This is to prevent multiple headers being prepended
    # for multi-recipient mail.
    if instance in instance_dict:
        found_instance = instance_dict[instance]
    else:
        found_instance = []
    # If this is not the first recipient for the message, we need to know if
    # there is a previous prepend to make sure we don't prepend more than once.
    if found_instance:
        if found_instance[6] != 'prepend':
            last_action = found_instance[3]
        else:
            last_action = found_instance[6]
    else:
        last_action = ""
    #  start query
    spfResult = None
    spfReason = None
    '''Data structure for results is a list of:
        [0] SPF result 
        [1] SPF reason
        [2] Identity (HELO/Mail From)
        [3] Action based on local policy
        [4] Header
        [5] Per user (stored data was based on per user policy)
        [6] last_action (need to know if we've prepended already)'''
    if debugLevel >= 4: syslog.syslog('Cached data for this instance: %s' % str(found_instance))
    if not found_instance or found_instance[5] or peruser:
        # Do not check SPF for localhost addresses
        skip_check = _spfbypass(data, 'skip_addresses', configData)
        if skip_check[0]:
            skip_data = ["N/A", "Skip SPF checks on localhost", "N/A", "prepend", skip_check[1]]
            if last_action != 'prepend':
                skip_data.append(peruser)
                skip_data.append('prepend')
                if not found_instance or found_instance[5]:
                    instance_dict[instance] = skip_data
                return (('prepend', skip_check[1], instance_dict ))
            else:
                return(( 'dunno', 'Header already pre-pended', instance_dict ))
        # Whitelist designated IP addresses from SPF checks (e.g. secondary MX or 
        # known forwarders.
        ip_whitelist = _spfbypass(data, 'Whitelist', configData)
        if ip_whitelist:
            if ip_whitelist[0]:
                skip_data = ["N/A", "Skip SPF checks for whitelisted IP addresses", "N/A", "prepend", skip_check[1]]
                if last_action != 'prepend':
                    skip_data.append(peruser)
                    skip_data.append('prepend')
                    if not found_instance or found_instance[5]:
                        instance_dict[instance] = skip_data
                if last_action != 'prepend':
                    return (('prepend', ip_whitelist[1], instance_dict ))
                else:
                    return(( 'dunno', 'Header already pre-pended', instance_dict ))
        # Whitelist designated Domain's sending addresses from SPF checks (e.g. 
        # known forwarders.
        if configData.get('Domain_Whitelist'):
            domain_whitelist = _spfbypass(data, 'Domain_Whitelist', configData)
            if domain_whitelist:
                if domain_whitelist[0]:
                    skip_data = ["N/A", "Skip SPF checks for whitelisted domains", "N/A", "prepend", skip_check[1]]
                    if last_action != 'prepend':
                        skip_data.append(peruser)
                        skip_data.append('prepend')
                        if not found_instance or found_instance[5]:
                            instance_dict[instance] = skip_data
                    if last_action != 'prepend':
                        return (('prepend', domain_whitelist[1], instance_dict ))
                    else:
                        return(( 'dunno', 'Header already pre-pended', instance_dict ))
        # Whitelist designated Domain's sending addresses from SPF checks (e.g.
        # known forwarders, but based on PTR match
        if configData.get('Domain_Whitelist_PTR'):
            domain_whitelist = _spfbypass(data, 'Domain_Whitelist_PTR', configData)
            if domain_whitelist:
                if domain_whitelist[0]:
                    skip_data = ["N/A", "Skip SPF checks for whitelisted hosts (by PTR)", "N/A", "prepend", skip_check[1]]
                    if last_action != 'prepend':
                        skip_data.append(peruser)
                        skip_data.append('prepend')
                        if not found_instance or found_instance[5]:
                            instance_dict[instance] = skip_data
                    if last_action != 'prepend':
                        return (('prepend', domain_whitelist[1], instance_dict ))
                    else:
                        return(( 'dunno', 'Header already pre-pended', instance_dict ))
        receiver=socket.gethostname()
        sender = data.get('sender')
        helo = data.get('helo_name')
        if not sender and not helo:
            if debugLevel >= 2: syslog.syslog('spfcheck: No sender or helo, exiting')
            return(( None, None, instance_dict ))
        Mail_From_pass_restriction = configData.get('Mail_From_pass_restriction')
        HELO_pass_restriction = configData.get('HELO_pass_restriction')
        helo_result = ['None',]
        # First do HELO check
        #  if no helo name sent, use domain from sender for later use.
        if not helo:
            foo = string.split(sender, '@', 1)
            if len(foo) <  2: helo = 'unknown'
            else: helo = foo[1]
        else:
            if configData.get('HELO_reject') != 'No_Check':
                helo_fake_sender = 'postmaster@' + helo
                res = spf.check2(ip, helo_fake_sender, helo)
                helo_result = [res[0], res[1]]
                helo_result.append('helo') 
                helo_result[0] = helo_result[0].lower()
                helo_result[0] = helo_result[0].capitalize()
                helo_resultpolicy, local = _get_resultcodes(configData, 'helo')
                if debugLevel >= 2:
                    syslog.syslog('spfcheck: pyspf result: "%s"' % str(helo_result))
                if configData.get('HELO_reject') == 'Null' and sender:
                    helo_result.append('dunno')
                else:
                    for poss_actions in helo_resultpolicy:
                        if helo_result[0] in helo_resultpolicy[poss_actions]:
                            action = poss_actions
                            helo_result.append(action)
                    if local['local_helo']:
                        helo_result[1] = 'Receiver policy for SPF ' + helo_result[0]
                if sender == '':
                    header_sender = '<>'
                else:
                    header_sender = sender
                if helo_result[0] == 'None':
                    helo_result[1] = "no SPF record"
                spfDetail = ('identity=%s; client-ip=%s; helo=%s; envelope-from=%s; receiver=%s '
                    % (helo_result[2], ip, helo, header_sender, data.get('recipient', '<UNKNOWN>')))
                if debugLevel >= 1:
                    logdata = str(helo_result[0]) + "; " + spfDetail
                    syslog.syslog(logdata)
                header = ''
                if 'SPF' in configData.get('Header_Type') and 'AR' in configData.get('Header_Type'):
                    syslog.syslog(syslog.LOG_ERR, 'Header_Type includes both SPF and AR - invalid configuration.')
                    raise SyntaxError('Header_Type includes both SPF and AR - invalid configuration.')
                if 'SPF' in configData.get('Header_Type'):
                    header = 'Received-SPF: '+ helo_result[0] + ' (' + helo_result[1] +') ' + spfDetail
                elif 'AR' in configData.get('Header_Type'):
                    try:
                        header += str(authres.AuthenticationResultsHeader(authserv_id = configData.get('Authserv_Id'),
                            results = [authres.SPFAuthenticationResult(result = helo_result[0],
                            result_comment = helo_result[1],
                            smtp_helo = helo, smtp_helo_comment =
                            'client-ip={0}; helo={1}; envelope-from={2}; receiver={3}'.format(ip, helo, header_sender, data.get('recipient', '<UNKNOWN>')))]))
                    except TypeError as x:
                        if str(x).startswith('sequence item 2'):
                            syslog.syslog(syslog.LOG_ERR, 'Authserv_Id not set for authentication results header - invalid configuration.')
                            raise SyntaxError('Authserv_Id not set for authentication results header - invalid configuration.') 
                helo_result.append(header)
                helo_result.append(peruser)
                helo_result.append(helo_result[3])
                if not found_instance or found_instance[5]:
                    if found_instance and found_instance[6] == "prepend":
                        helo_result[6] = "prepend"
                    instance_dict[instance] = helo_result
                if HELO_pass_restriction and helo_result[0] == 'Pass':
                    restrict_name = HELO_pass_restriction
                # Only act on the HELO result if it is authoritative.
                if helo_result[3] == 'reject':
                    if configData.get('No_Mail'):
                        # If only rejecting on "v=spf1 -all", we need to know now
                        q = spf.query(i='127.0.0.1', s='localhost', h='unknown', receiver=socket.gethostname())
                        record = q.dns_spf(helo)
                        if record != "v=spf1 -all":
                            if last_action != 'prepend':
                                # Prepend instead of reject if it's not a no mail record
                                helo_result[3] = 'prepend'
                            else:
                                return(( 'dunno', 'Header already pre-pended', instance_dict ))
                    if helo_result[3] == 'reject': # It may not anymore
                        header = "Message rejected due to: " + helo_result[1] + \
                            ". Please see http://www.openspf.net/Why?s=helo;id=" \
                            + helo + ";ip=" + ip + ";r=" + data.get('recipient')
                        return(( 'reject', header, instance_dict ))
                if helo_result[3] == 'defer':
                    header = "Message deferred due to: " + helo_result[1] + \
                        ". Please see http://www.openspf.net/Why?s=helo;id=" + helo + \
                        ";ip=" + ip + ";r=" + data.get('recipient')
                    return(( 'defer', header, instance_dict ))
        # Second do Mail From Check
        if sender == '':
            if configData.get('HELO_reject') != 'No_Check':
                if helo_result[3] == 'reject':
                    if configData.get('No_Mail'):
                        # If only rejecting on "v=spf1 -all", we need to know now
                        q = spf.query(i='127.0.0.1', s='localhost', h='unknown', receiver=socket.gethostname())
                        record = q.dns_spf(helo)
                        if record != "v=spf1 -all":
                            if last_action != 'prepend':
                                # Prepend instead of reject if it's not a no mail record
                                helo_result[3] = 'prepend'
                            else:
                                return(( 'dunno', 'Header already pre-pended', instance_dict ))
                    if helo_result[3] == 'reject': # It may not anymore
                        header = "Message rejected due to: " + helo_result[1] + \
                            ". Please see http://www.openspf.net/Why?s=helo;id=" + helo + \
                            ";ip=" + ip + ";r=" + data.get('recipient')
                if helo_result[3] == 'defer':
                    header = "Message deferred due to: " + helo_result[1] + \
                        ". Please see http://www.openspf.net/Why?s=helo;id=" + helo + \
                        ";ip=" + ip + ";r=" + data.get('recipient')
                if HELO_pass_restriction and helo_result[0] == 'Pass':
                    restrict_name = HELO_pass_restriction
                    return('result_only', restrict_name, instance_dict)
                return(( helo_result[3], header, instance_dict ))
        else:
            if configData.get('Mail_From_reject') != 'No_Check':
                res = spf.check2(ip, sender, helo)
                mfrom_result = [res[0], res[1]]
                mfrom_result.append('mailfrom')
                mfrom_result[0] = mfrom_result[0].lower()
                mfrom_result[0] = mfrom_result[0].capitalize()
                mfrom_resultpolicy, local = _get_resultcodes(configData, 'mfrom')
                if debugLevel >= 2:
                    syslog.syslog('spfcheck: pyspf result: "%s"' % str(mfrom_result))
                for poss_actions in mfrom_resultpolicy:
                    if mfrom_result[0] in mfrom_resultpolicy[poss_actions]:
                        action = poss_actions
                        mfrom_result.append(action)
                if local['local_mfrom']:
                    mfrom_result[1] = 'Receiver policy for SPF ' + mfrom_result[0]
                if mfrom_result[0] == 'None':
                    mfrom_result[1] = 'no SPF record'
                if mfrom_result[0] != 'None' or (mfrom_result[0] == 'None' and helo_result[0] == 'None'):
                    spfDetail = \
                        ('identity=%s; client-ip=%s; helo=%s; envelope-from=%s; receiver=%s '
                        % (mfrom_result[2], ip, helo, sender, data.get('recipient', '<UNKNOWN>')))
                    if debugLevel >= 1:
                        logdata = str(mfrom_result[0]) + "; " + spfDetail
                        syslog.syslog(logdata)
                    header = ''
                    if 'SPF' in configData.get('Header_Type') and 'AR' in configData.get('Header_Type'):
                        syslog.syslog(syslog.LOG_ERR, 'Header_Type includes both SPF and AR - invalid configuration.')
                        raise SyntaxError('Header_Type includes both SPF and AR - invalid configuration.')
                    if 'SPF' in configData.get('Header_Type'):
                        header = 'Received-SPF: '+ mfrom_result[0] + ' (' + mfrom_result[1] +') ' + spfDetail
                    elif 'AR' in configData.get('Header_Type'):
                        try:
                            header += str(authres.AuthenticationResultsHeader(authserv_id = configData.get('Authserv_Id'),
                                results = [authres.SPFAuthenticationResult(result = mfrom_result[0],
                                result_comment = mfrom_result[1],
                                smtp_mailfrom = spf.split_email(sender,'example.com')[1], smtp_mailfrom_comment =
                                'client-ip={0}; helo={1}; envelope-from={2}; receiver={3}'.format(ip, helo, sender, data.get('recipient', '<UNKNOWN>')))]))
                        except TypeError as x:
                            if str(x).startswith('sequence item 2'):
                                syslog.syslog(syslog.LOG_ERR, 'Authserv_Id not set for authentication results header - invalid configuration.')
                                raise SyntaxError('Authserv_Id not set for authentication results header - invalid configuration.') 
                    mfrom_result.append(header)
                    mfrom_result.append(peruser)
                    mfrom_result.append(mfrom_result[3])
                    if not found_instance or foundinstance[5]:
                        if found_instance and found_instance[6] == "prepend":
                            mfrom_result[6] = "prepend"
                        instance_dict[instance] = mfrom_result
                if (Mail_From_pass_restriction and mfrom_result[0] == 'Pass') or \
                   (HELO_pass_restriction and helo_result[0] == 'Pass'):
                    if mfrom_result[0] == 'Pass':
                        restrict_name = Mail_From_pass_restriction
                    return('result_only', restrict_name, instance_dict)
                # Act on the Mail From result if it is authoritative.
                if mfrom_result[3] == 'reject':
                    if configData.get('No_Mail'):
                        # If only rejecting on "v=spf1 -all", we need to know now
                        q = spf.query(i='127.0.0.1', s='localhost', h='unknown', receiver=socket.gethostname())
                        record = q.dns_spf(sender)
                        if record != "v=spf1 -all":
                            if last_action != 'prepend':
                                # Prepend instead of reject if it's not a no mail record
                                mfrom_result[3] = 'prepend'
                            else:
                                return(( 'dunno', 'Header already pre-pended', instance_dict ))
                    if mfrom_result[3] == 'reject': # It may not be anymore
                        header = "Message rejected due to: " + mfrom_result[1] + \
                            ". Please see http://www.openspf.net/Why?s=mfrom;id=" + sender + \
                            ";ip=" + ip + ";r=" + data.get('recipient')
                        return(( 'reject', header, instance_dict ))
                if mfrom_result[3] == 'defer':
                    header = "Message deferred due to: " + mfrom_result[1] + \
                        ". Please see http://www.openspf.net/Why?s=mfrom;id=" + sender + \
                        ";ip=" + ip + ";r=" + data.get('recipient')
                    return(( 'defer', header, instance_dict ))
                if mfrom_result[3] != 'dunno' or helo_result[3] =='dunno':
                    if last_action != 'prepend':
                        return(( 'prepend', header, instance_dict ))
                    else:
                        return(( 'dunno', 'Header already pre-pended', instance_dict ))
            else:
                if configData.get('HELO_reject') != 'No_Check':
                    if helo_result[3] == 'reject':
                        if configData.get('No_Mail'):
                            # If only rejecting on "v=spf1 -all", we need to know now
                            q = spf.query(i='127.0.0.1', s='localhost', h='unknown', receiver=socket.gethostname())
                            record = q.dns_spf(helo)
                            if record != "v=spf1 -all":
                                if last_action != 'prepend':
                                    # Prepend instead of reject if it's not a no mail record
                                    helo_result[3] = 'prepend'
                                else:
                                    return(( 'dunno', 'Header already pre-pended', instance_dict ))
                        if helo_result[3] == 'reject': # It may not anymore
                            header = "Message rejected due to: " + helo_result[1] + \
                                ". Please see http://www.openspf.net/Why?s=helo;id=" \
                                + helo + ";ip=" + ip + ";r=" + data.get('recipient')
                            return(( 'reject', header, instance_dict ))
                    if helo_result[3] == 'defer':
                        header = "Message deferred due to: " + helo_result[1] + \
                            ". Please see http://www.openspf.net/Why?s=helo;id=" + helo + \
                            ";ip=" + ip + ";r=" + data.get('recipient')
                        return(( 'defer', header, instance_dict ))
                    if last_action != 'prepend':
                        return(( 'prepend', header, instance_dict ))
                    else:
                        return(( 'dunno', 'Header already pre-pended', instance_dict ))
    else:
        cached_instance = instance_dict[instance]
        if cached_instance[3] == 'prepend':
            return(( 'dunno', 'Header already pre-pended', instance_dict ))
        else:
            return(( cached_instance[3], cached_instance[4], instance_dict ))
    return(( 'None', 'None', instance_dict ))

###################################################
#  load config file  {{{1
#  Default location:
configFile = '/etc/postfix-policyd-spf-python/policyd-spf.conf'
if len(sys.argv) > 1:
    if sys.argv[1] in ( '-?', '--help', '-h' ):
        print('usage: policyd-spf [<configfilename>]')
        sys.exit(1)
    configFile = sys.argv[1]

configGlobal = policydspfsupp._processConfigFile(filename = configFile)

#  loop reading data  {{{1
debugLevel = configGlobal.get('debugLevel', 1)
if debugLevel >= 3: syslog.syslog('Starting')
instance_dict = {'0':'init',}
instance_dict.clear()
data = {}
lineRx = re.compile(r'^\s*([^=\s]+)\s*=(.*)$')
while 1:
    line = sys.stdin.readline()
    if not line: break
    line = line.rstrip()
    if debugLevel >= 4: syslog.syslog('Read line: "%s"' % line)

    #  end of entry  {{{2
    if not line:
        peruser = False
        if debugLevel >= 4: syslog.syslog('Found the end of entry')
        configData = dict(list(configGlobal.items()))
        if configData.get('Per_User'):
            import policydspfuser
            configData, peruser = policydspfuser._datacheck(configData, data.get('recipient'))
            if debugLevel >= 2 and peruser: syslog.syslog('Per user configuration data in use for: %s' \
                % str(data.get('recipient')))
        if debugLevel >= 3: syslog.syslog('Config: %s' % str(configData))
        #  run the checkers  {{{3
        checkerValue = None
        checkerReason = None
        checkerValue, checkerReason, instance_dict = _spfcheck(data, 
                    instance_dict, configData, peruser)
        if configData.get('defaultSeedOnly') == 0 and checkerValue != 'prepend':
            checkerValue = None
            checkerReason = None

        #  handle results  {{{3
        if debugLevel >= 3: syslog.syslog('Action: {0}: Text: {1}'.format(checkerValue, checkerReason))
        if checkerValue == 'reject':
            sys.stdout.write('action=550 %s\n\n' % checkerReason)

        elif checkerValue == 'prepend':
            if configData.get('Prospective'):
                sys.stdout.write('action=dunno\n\n')
            else:
                sys.stdout.write('action=prepend %s\n\n' % checkerReason)

        elif checkerValue == 'defer':
            sys.stdout.write('action=defer_if_permit %s\n\n' % checkerReason)

        elif checkerValue == 'warn':
            sys.stdout.write('action=warn %s\n\n' % checkerReason)

        elif checkerValue == 'result_only':
            sys.stdout.write('action=%s\n\n' % checkerReason)
        else:
            sys.stdout.write('action=dunno\n\n')

        #  end of record  {{{3
        sys.stdout.flush()
        data = {}
        continue

    #  parse line  {{{2
    m = lineRx.match(line)
    if not m: 
        syslog.syslog('ERROR: Could not match line "%s"' % line)
        continue

    #  save the string  {{{2
    key = m.group(1)
    value = m.group(2)
    if key not in [ 'protocol_state', 'protocol_name', 'queue_id' ]:
        value = value.lower()
    data[key] = value

if debugLevel >= 3: syslog.syslog('Normal exit')