1. ábra - IP címek feloldása

Számunkra az SBL és XBL osztályok az érdekesek. A biztosan SPAM küldőket letiltjuk.

Az erre használható Zorp-6-os proxy osztály:‍

class RBLSpamFilterSmtpProxy(SmtpProxy):

    def config(self):

        super(RBLSpamFilterSmtpProxy, self).config()

        self.request["MAIL"] = (SMTP_REQ_POLICY, self.checkRBL)


    def checkRBL(self, cmd, param):

        proxyLog(self, CORE_POLICY, 5, "Starting RBL checking.")

        l = string.split(self.session.client_address.ip_s, ".")

        l.reverse()

        lookup_host = string.join(l, ".") + "." + self.rbl_domain

        proxyLog(self, CORE_POLICY, 5, "Looking up RBL; query_string='%s'", lookup_host)

        try:

           addr = socket.gethostbyname(lookup_host)

        except socket.error:

            addr = None

     if addr:

         if '127.0.0.2' in addr or '127.0.0.3' in addr or '127.0.0.9' in addr:

            proxyLog(self, CORE_POLICY, 2, "Address in Direct RBL, rejecting; ip='%s', rbl='%s', response='%s'",
                 (self.session.client_address.ip_s, self.rbl_domain, addr))

             return SMTP_REQ_ABORT

            elif '127.0.0.4' in addr or '127.0.0.5' in addr or '127.0.0.6' in addr or '127.0.0.7' in addr:

            proxyLog(self, CORE_POLICY, 2, "Address in XBL RBL, rejecting; ip='%s', rbl='%s', response='%s'", 
            (self.session.client_address.ip_s, self.rbl_domain, addr))

            return SMTP_REQ_ABORT

        else:

            return SMTP_REQ_ACCEPT


"BlackList"""

MatcherPolicy(name="EmailBlackList", matcher=RegexpFileMatcher(match_fname="/etc/zorp/email-blacklist",
 ignore_fname="/etc/zorp/email-blacklist.ignore"))

MatcherPolicy(name="InterSMTPRecipientMatcher", matcher=RegexpFileMatcher(match_fname="/etc/zorp/email-recipient",
 ignore_fname="/etc/zorp/email-recipient.ignore"))



class InterSmtpProxy(RBLSpamFilterSmtpProxy):

    def config(self):

        RBLSpamFilterSmtpProxy.config(self)

        self.request_stack["*"]=(SMTP_STK_MIME,
         (Z_STACK_PROVIDER, "LocalZCV", "InterSMTPScanning"))        

        self.relay_domains=("saját domain helye.hu", )

        self.sender_matcher="EmailBlackList"

        self.recipient_matcher="InterSMTPRecipientMatcher"

        self.rbl_domain="zen.spamhaus.org"

        self.max_request_length=1024

        self.unconnected_response_code=451

        self.require_crlf=FALSE

        self.relay_check=TRUE

        self.error_soft=TRUE
        

A proxyt érdemes az SMTP autentikációt ellenőrző proxyval kombinálni, amennyiben a belső szerver ezt támogatja.

class AuthRelaySmtpProxy(SmtpProxy):

    def config(self):

        SmtpProxy.config(self)

        self.response["AUTH", "235"] = (SMTP_RSP_POLICY, self.authsucc)

        

    def authsucc(self, cmd, cmd_param, rsp, rsp_param):

        self.relay_check = FALSE

        log(None, CORE_POLICY, 3, "Relay-check disabled after successful auth;
         rsp='%s'; rsp_param='%s'", (rsp,rsp_param,))

        return SMTP_RSP_ACCEPT