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</o:shapelayout></xml><![endif]--></head><body lang=PT-BR link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal><span lang=EN-US>Sirs. I tested the stunnel client connect to a stunnel server to proxy transparent a http traffic.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>I used a traffic generator from Ixia (BPS), a tap to get the traffic between stunnel�s using ntop license pf_ring (Kernel bypass) with tcpdump accessing their libs and export pcaps from source and destination from Ixia.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>Transparent source worked flawless easily using the information on man page.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>Transparent destination didn�t worked. The instructions in the stunnel documentation for each are:<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>/sbin/iptables -I INPUT -i client_interface -p tcp --dport 443 (I�m using default port os https) -j ACCEPT ----- It is filter INPUT that is executed after routing decision after nat to allow packets with destination port 443<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>/sbin/iptables -t nat -I PREROUTING -p tcp --dport 80 (Destination port of http in client_interface \<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>������� -i client_interface -j DNAT --to-destination 9.0.0.2:443 (connect destination on server Stunnel)<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>The second input in iptables is executed before the routing decision and that is the problem. Looking the hit count of in iptables the nat table PREROUTING always have a hit but the filter table �filter INPUT doesn�t.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>I set a policy routing to delivey packets to 9.0.0.2:443 to local process and the filter table� filter INPUT started to receive the hit in the counters as well but stunnel didn�t worked.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>If I change the connect destination address to local interface 9.0.0.1:443 I do not need the pocily routing since it�s local but Stunnel did not worked too.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>The stunnel configuration for the client is bellow:<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>#setgid = root<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>#setuid = root<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>debug = 7<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>log = overwrite<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>syslog = no<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>output = /root/stunnel.log<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>;engine = ENGINE_ID<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>;engineCtrl = COMMAND[:PARAMETER]<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>;engineDefault = TASK_LIST<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>[http]<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>client = yes<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>accept = 6.0.0.1:80<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>;connect = 9.0.0.2:443<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>ciphers = AES128-GCM-SHA256<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>requireCert = no<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>sslVersion = TLSv1.2<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>transparent = destination<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-US>At the end I�d like to use both source and destination but I�m testing separated.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>Does anyone know if there is a bug related or if there is a version working fine?<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>Even with a lot o resource I don�t have more what to do about and any help would be appreciated.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-US>Luis Monteiro<o:p></o:p></span></p></div></body></html>