December 2008 - stunnel-users

Re: [stunnel-users] Cannot connect to SBC/yahoo to send (or telnet)
by Leandro Avila 12 Dec '08

12 Dec '08

Not sure if ranting will get you the kind of answer that you look for but it was certainly entertaining for me. Anyway... I agree, some times things can be a little frustraiting but I guess that depends on how much time on how much work you want to put into it. Sorry to hear you feel stupid. Everyone has to start from 0 at shome point and it takes time to get a good handle to how things work. The question is... do you really want to know how things work or just want them to work without having to do much? A google search of "SSL Explained" http://wildbill.nulldevice.net/presentations/sslpreso/ I liked slide 11/35 nice little diagram of SSL handshake wich helps to visualize in very general terms how an SSL connection works. The rest of the slides are good too check them out! In your particular case that forced you to change from plain-text to SSL connections to your mail server. You had a couple of options. - First and most obvious is to use SSL support build into your mail client (Thunderbird, Outlook,etc) most if not all modern mail clients support SSL natively. No need for stunnel there. - If your mail client does not support SSL then stunnel is the way to go. But your issue is on how stunnel is being used. As client. When you are a client... you always want to verify your server. You want to make sure you are connected to the right server. You want to use verify=2 in stunnel.conf How do we verify that the server I just connected is in fact the right server? That is the Certificate Authority's job. We ultimately have to trust the CA they issued the certificate for the server owner. They signed the certificate with their key. and we use the CA's certificate to verify that signature. Here is the catch... operating systems, and some programs are shipped with a prebuild collection of CA certificates. Unfortunatelly stunnel does not. However, most CAs let you download their certificates for your own use. In your particular case, looks like the server you are connecting to uses a certificate issued by Equifax Secure Certificate Authority Here they have the download page for the CA Certificates. http://www.geotrust.com/resources/root-certificates/ You pointed out that they refuse connections if the client presents a certificate. Yes, that is somehow a common practice. Mutual authentication (both server and client send certificates to each other and verify them) is impractical in some cases. Thanks ----------------- Leandro Avila

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Cannot connect to SBC/yahoo to send (or telnet)
by James Moe 06 Dec '08

06 Dec '08

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Hello, (I sent this yesterday but that one seems to have gotten lost....) Stunnel v4.20. When connecting to SBC/Yahoo, the session is terminated with a "bad certificate" message. See the log below. The tech folks claim all is well at their end. Is there something I am missing here? Here is the conf file: ....[ conf ].... socket = l:TCP_NODELAY=1 socket = r:TCP_NODELAY=1 client = yes output = G:/c/voice/pmmdev/testcase/bin/stunnel.log verify = 0 debug = 7 cert = g:/c/voice/pmmdev/testcase/bin/sma-test.pem [sbc] accept = localhost:6325 connect = smtp.att.yahoo.com:465 ....[ end conf ].... ....[ connection log ].... 2008.11.11 00:14:17 LOG7[223:1737]: sbc accepted FD=15 from 127.0.0.1:61053 2008.11.11 00:14:17 LOG7[223:1737]: Creating a new thread 2008.11.11 00:14:17 LOG7[223:1737]: New thread created 2008.11.11 00:14:17 LOG7[251:1737]: sbc started 2008.11.11 00:14:17 LOG7[251:1737]: FD 15 in non-blocking mode 2008.11.11 00:14:17 LOG7[251:1737]: TCP_NODELAY option set on local socket 2008.11.11 00:14:17 LOG5[251:1737]: sbc accepted connection from 127.0.0.1:61053 2008.11.11 00:14:17 LOG7[251:1737]: FD 16 in non-blocking mode 2008.11.11 00:14:17 LOG7[251:1737]: sbc connecting 69.147.64.31:465 2008.11.11 00:14:17 LOG7[251:1737]: connect_wait: waiting 10 seconds 2008.11.11 00:14:17 LOG7[251:1737]: connect_wait: connected 2008.11.11 00:14:17 LOG5[251:1737]: sbc connected remote server from 192.168.69.14:61054 2008.11.11 00:14:17 LOG7[251:1737]: Remote FD=16 initialized 2008.11.11 00:14:17 LOG7[251:1737]: TCP_NODELAY option set on remote socket 2008.11.11 00:14:17 LOG7[251:1737]: SSL state (connect): before/connect initialization 2008.11.11 00:14:17 LOG7[251:1737]: SSL state (connect): SSLv3 write client hello A 2008.11.11 00:14:17 LOG7[251:1737]: SSL state (connect): SSLv3 read server hello A 2008.11.11 00:14:17 LOG5[251:1737]: VERIFY IGNORE: depth=0, /C=US/ST=California/L=Santa Clara/O=Yahoo! Inc./OU=Yahoo/CN=smtp.att.yahoo.com 2008.11.11 00:14:17 LOG5[251:1737]: VERIFY OK: depth=0, /C=US/ST=California/L=Santa Clara/O=Yahoo! Inc./OU=Yahoo/CN=smtp.att.yahoo.com 2008.11.11 00:14:17 LOG5[251:1737]: VERIFY IGNORE: depth=0, /C=US/ST=California/L=Santa Clara/O=Yahoo! Inc./OU=Yahoo/CN=smtp.att.yahoo.com 2008.11.11 00:14:17 LOG5[251:1737]: VERIFY OK: depth=0, /C=US/ST=California/L=Santa Clara/O=Yahoo! Inc./OU=Yahoo/CN=smtp.att.yahoo.com 2008.11.11 00:14:17 LOG5[251:1737]: VERIFY IGNORE: depth=0, /C=US/ST=California/L=Santa Clara/O=Yahoo! Inc./OU=Yahoo/CN=smtp.att.yahoo.com 2008.11.11 00:14:17 LOG5[251:1737]: VERIFY OK: depth=0, /C=US/ST=California/L=Santa Clara/O=Yahoo! Inc./OU=Yahoo/CN=smtp.att.yahoo.com 2008.11.11 00:14:17 LOG7[251:1737]: SSL state (connect): SSLv3 read server certificate A 2008.11.11 00:14:17 LOG7[251:1737]: SSL state (connect): SSLv3 read server certificate request A 2008.11.11 00:14:17 LOG7[251:1737]: SSL state (connect): SSLv3 read server done A 2008.11.11 00:14:17 LOG7[251:1737]: SSL state (connect): SSLv3 write client certificate A 2008.11.11 00:14:17 LOG7[251:1737]: SSL state (connect): SSLv3 write client key exchange A 2008.11.11 00:14:17 LOG7[251:1737]: SSL state (connect): SSLv3 write certificate verify A 2008.11.11 00:14:17 LOG7[251:1737]: SSL state (connect): SSLv3 write change cipher spec A 2008.11.11 00:14:17 LOG7[251:1737]: SSL state (connect): SSLv3 write finished A 2008.11.11 00:14:17 LOG7[251:1737]: SSL state (connect): SSLv3 flush data 2008.11.11 00:14:18 LOG7[251:1737]: SSL alert (read): fatal: bad certificate 2008.11.11 00:14:18 LOG3[251:1737]: SSL_connect: 14094412: error:14094412:SSL routines:SSL3_READ_BYTES:sslv3 alert bad certificate 2008.11.11 00:14:18 LOG5[251:1737]: Connection reset: 0 bytes sent to SSL, 0 bytes sent to socket 2008.11.11 00:14:18 LOG7[251:1737]: sbc finished (0 left) ....[ end log ].... - -- jimoe (at) sohnen-moe (dot) com -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.7 (OS/2) iD8DBQFJGe4zzTcr8Prq0ZMRAhSPAJ4h6YHyR+/W5brb7FK1tbbW1zYZ+wCglxpC 9k2qqpP2hN99BL0TnsNhlnw= =P74g -----END PGP SIGNATURE-----

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Test, test. Hello?
by James Moe 06 Dec '08

06 Dec '08

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Hello, I have not received a posting for several days. Has the list really gone that quiet? - -- jimoe (at) sohnen-moe (dot) com -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.7 (OS/2) iD4DBQFJOXHezTcr8Prq0ZMRAqqQAJ0aUC0ZyZC+85WF4WZN3nntQjfrxgCY/zjt 3Jlthcur9UTtXOnNkVcPFg== =scXZ -----END PGP SIGNATURE-----

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