flowsynth.py 文件源码

def resolve_dns(self, shost):
        """Perform DNS lookups once per file, and cache the results. tested."""
        rdns = r"^(([0-9]|[1-9][0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])\.){3}([0-9]|[1-9][0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])$"
        if (re.match(rdns, shost) == None):
            if shost in self.dnscache:
                logging.debug("Host %s in DNSCACHE, returned %s", shost, self.dnscache[shost])
                shost = self.dnscache[shost]
            else:
                logging.debug("Host %s not in DNSCACHE", shost)
                #try socket lookupt
                try:
                    resolved_ip = socket.gethostbyname(shost)
                    self.dnscache[shost] = resolved_ip
                    logging.debug("Resolved %s to %s", shost, resolved_ip)
                    shost = resolved_ip
                except socket.gaierror:
                    compiler_bailout("Cannot resolve %s" % shost)
        return shost