- stunnel-users - stunnel.org

Server connecting back to client?
by Joshua Kugler 02 Dec '05

02 Dec '05

I've looked through the man pages, FAQ's, examples, and found one post (without a reply: http://stunnel.mirt.net/pipermail/stunnel-users/2005-May/000487.html) about this, but still don't have my question answered. I have a machine outside the firewall (let's call it outThere) that needs to connect back to a machine inside the firewall (let's call in inHere) for backup procedures. Now, because of the firewall, outThere cannot connect to inHere, but inHere can connect to anything on outThere that it wants. Can I initiate an stunnel connection from inHere to outThere, and then have stunnel on outThere listen on a localhost port, which, when connected to, would actually forward the connection (over SSL) back to a configured port on inHere? Is this at all doable? j----- k----- -- Joshua Kugler CDE System Administrator http://distance.uaf.edu/

2 1

Stunnel sending ICMP packet at startup
by Paul Jones 30 Nov '05

30 Nov '05

Hi there, I have set up Stunnel on both the server and the client. There is a firewall on the server side that only allows TCP connections through. When Stunnel is started up on the client side, the firewall is actually receiving an ICMP packet, not a TCP. Is this how Stunnel should be working? I assume it's doing a ping or something at startup. Thanks in advance. Paul _________________________________________________________________ SEEK: Over 80,000 jobs across all industries at Australia's #1 job site. http://ninemsn.seek.com.au?hotmail

2 1

4th Dimension and Stunnel
by Mark 28 Nov '05

28 Nov '05

Does anyone have a sample config file to allow 4th Dimension client and server to use stunnel?

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How to protect private key in Windows XP Home
by Andrus 28 Nov '05

28 Nov '05

My stunnel client must start without user intervention. So I installed stunnel in client mode in a Windows XP Home computer as XP service. In XP Proffesional I can specify that only Administrators group has access to stunnel directory. XP Home does not have security tab in folder properties. Any person working in XP Home compter can copy stunnel private key How to protect private key from copying ? Andrus. My stunnel.conf file: Cafile=server.crt cert=privkey.pem client = yes service=RDPClient verify = 2 [terminal server] accept = 83389 connect = 1.2.3.4:83389

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socklen_t undeclared
by tc 24 Nov '05

24 Nov '05

Hi, I'm getting socklet_t undeclared in client.c making stunnel4.14 in an embedded linux 2.038 system. What can I do? Thanks TC __________________________________ Meet your soulmate! Yahoo! Asia presents Meetic - where millions of singles gather http://asia.yahoo.com/meetic

2 1

Newbie Question
by Mark 23 Nov '05

23 Nov '05

I am completely new to SSL and stunnel. I need to test the differences between 4th Dimension's SSL and doing the same thing without the 4D implementation of SSL using stunnel. Can anyone please tell me where to get started? Mark Zinke

2 1

Call for Beta Testers: Tool similar to Stunnel.
by Wilfred Nilsen 22 Nov '05

22 Nov '05

We have designed a tool that is similar to Stunnel and we would like to know if anyone would be interested in testing the tool. A short introduction: The Barracuda HTTPS tunnel allows you to encrypt arbitrary TCP connections inside SSL. The HTTPS tunnel allows you to secure non-SSL aware services such as TELNET, FTP, VNC, etc., by having the HTTPS tunnel provide the encryption. The HTTPS tunnel can also be used, for example, to tunnel traffic out from behind a restrictive firewall/proxy that only allows outgoing HTTPS web connections. The client is a Java program that can either be downloaded and started from the command prompt or started using Java Web Start. The server is BarracudaDrive. http://barracudaserver.com/examples/BarracudaDrive/ We will make the beta program (the server and client) available if anyone is interested in testing the tool and give us feedback. We are specifically interested in beta testers that are behind a restrictive company proxy. Thanks, Wilfred

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Re: [stunnel-users] Problem with Stunnel Working fine on the firstconnection and not on subsequent connections
by Kevin A. McGrail 19 Nov '05

19 Nov '05

> I'd try to disable chroot and run stunnel under strace with "foreground = yes" option. Mike, When running in foreground, with or without chroot, things work as expected. Without foreground, it did not work. Two key differences on the logs for each: Output of "Cleaning up the signal pipe" prior to checking the libwrap permissions a finish line of "ssmtp finished (0 left)" instead of "ssmtp finished (-1 left)" (Yes, this is a dual processor box.) It looks like the key problem lies in the regerenation of the standalone mode. Is there a way with v4 to just use inetd to answer on port 465, negotiate and connect on port 25 on another host because perhaps that will avoid the issue. Regards, KAM 2005.11.19 13:07:51 LOG7[3893:1024]: Key file: /usr/local/ssl/certs/stunnel.pem 2005.11.19 13:07:51 LOG6[3893:1024]: file ulimit = 1024 (can be changed with 'ulimit -n') 2005.11.19 13:07:51 LOG6[3893:1024]: poll() used - no FD_SETSIZE limit for file descriptors 2005.11.19 13:07:51 LOG5[3893:1024]: 500 clients allowed 2005.11.19 13:07:51 LOG7[3893:1024]: FD 4 in non-blocking mode 2005.11.19 13:07:51 LOG7[3893:1024]: FD 5 in non-blocking mode 2005.11.19 13:07:51 LOG7[3893:1024]: FD 6 in non-blocking mode 2005.11.19 13:07:51 LOG7[3893:1024]: SO_REUSEADDR option set on accept socket 2005.11.19 13:07:51 LOG7[3893:1024]: ssmtp bound to 0.0.0.0:465 2005.11.19 13:07:51 LOG7[3893:1024]: Created pid file /stunnel.pid [ed: 1st email] 2005.11.19 13:08:32 LOG7[3893:1024]: ssmtp accepted FD=7 from 66.149.103.32:3130 2005.11.19 13:08:32 LOG7[3898:1026]: ssmtp started 2005.11.19 13:08:32 LOG7[3898:1026]: FD 7 in non-blocking mode 2005.11.19 13:08:32 LOG7[3898:1026]: TCP_NODELAY option set on local socket 2005.11.19 13:08:32 LOG7[3898:1026]: FD 10 in non-blocking mode 2005.11.19 13:08:32 LOG7[3898:1026]: FD 11 in non-blocking mode 2005.11.19 13:08:32 LOG7[3893:1024]: Cleaning up the signal pipe 2005.11.19 13:08:32 LOG7[3898:1026]: Connection from 66.149.103.32:3130 permitted by libwrap 2005.11.19 13:08:32 LOG5[3898:1026]: ssmtp connected from 66.149.103.32:3130 2005.11.19 13:08:32 LOG7[3898:1026]: SSL state (accept): before/accept initialization 2005.11.19 13:08:32 LOG7[3898:1026]: SSL state (accept): SSLv3 read client hello A 2005.11.19 13:08:32 LOG7[3898:1026]: SSL state (accept): SSLv3 write server hello A 2005.11.19 13:08:32 LOG7[3898:1026]: SSL state (accept): SSLv3 write certificate A 2005.11.19 13:08:32 LOG7[3898:1026]: SSL state (accept): SSLv3 write server done A 2005.11.19 13:08:32 LOG7[3898:1026]: SSL state (accept): SSLv3 flush data 2005.11.19 13:08:32 LOG7[3898:1026]: SSL state (accept): SSLv3 read client key exchange A 2005.11.19 13:08:32 LOG7[3898:1026]: SSL state (accept): SSLv3 read finished A 2005.11.19 13:08:32 LOG7[3898:1026]: SSL state (accept): SSLv3 write change cipher spec A 2005.11.19 13:08:32 LOG7[3898:1026]: SSL state (accept): SSLv3 write finished A 2005.11.19 13:08:32 LOG7[3898:1026]: SSL state (accept): SSLv3 flush data 2005.11.19 13:08:32 LOG7[3898:1026]: 1 items in the session cache 2005.11.19 13:08:32 LOG7[3898:1026]: 0 client connects (SSL_connect()) 2005.11.19 13:08:32 LOG7[3898:1026]: 0 client connects that finished 2005.11.19 13:08:32 LOG7[3898:1026]: 0 client renegotiatations requested 2005.11.19 13:08:32 LOG7[3898:1026]: 1 server connects (SSL_accept()) 2005.11.19 13:08:32 LOG7[3898:1026]: 1 server connects that finished 2005.11.19 13:08:32 LOG7[3898:1026]: 0 server renegotiatiations requested 2005.11.19 13:08:32 LOG7[3898:1026]: 0 session cache hits 2005.11.19 13:08:32 LOG7[3898:1026]: 1 session cache misses 2005.11.19 13:08:32 LOG7[3898:1026]: 0 session cache timeouts 2005.11.19 13:08:32 LOG6[3898:1026]: SSL accepted: new session negotiated 2005.11.19 13:08:32 LOG6[3898:1026]: Negotiated ciphers: RC4-MD5 SSLv3 Kx=RSA Au=RSA Enc=RC4(128) Mac=MD5 2005.11.19 13:08:32 LOG7[3898:1026]: FD 10 in non-blocking mode 2005.11.19 13:08:32 LOG7[3898:1026]: ssmtp connecting 10.10.10.30:25 2005.11.19 13:08:32 LOG7[3898:1026]: connect_wait: waiting 10 seconds 2005.11.19 13:08:32 LOG7[3898:1026]: connect_wait: connected 2005.11.19 13:08:32 LOG7[3898:1026]: Remote FD=10 initialized 2005.11.19 13:08:32 LOG7[3898:1026]: TCP_NODELAY option set on remote socket 2005.11.19 13:08:33 LOG7[3898:1026]: Socket closed on read 2005.11.19 13:08:33 LOG7[3898:1026]: SSL write shutdown 2005.11.19 13:08:33 LOG7[3898:1026]: SSL alert (write): warning: close notify 2005.11.19 13:08:33 LOG7[3898:1026]: SSL_shutdown retrying 2005.11.19 13:08:33 LOG7[3898:1026]: SSL doesn't need to read or write 2005.11.19 13:08:33 LOG7[3898:1026]: SSL socket closed on SSL_read 2005.11.19 13:08:33 LOG7[3898:1026]: Socket write shutdown 2005.11.19 13:08:33 LOG5[3898:1026]: Connection closed: 834 bytes sent to SSL, 1358 bytes sent to socket 2005.11.19 13:08:33 LOG7[3898:1026]: ssmtp finished (0 left) [ed: 2nd email] 2005.11.19 13:08:40 LOG7[3893:1024]: ssmtp accepted FD=7 from 66.149.103.32:3137 2005.11.19 13:08:40 LOG7[3900:2050]: ssmtp started 2005.11.19 13:08:40 LOG7[3900:2050]: FD 7 in non-blocking mode 2005.11.19 13:08:40 LOG7[3900:2050]: TCP_NODELAY option set on local socket 2005.11.19 13:08:40 LOG7[3900:2050]: FD 10 in non-blocking mode 2005.11.19 13:08:40 LOG7[3900:2050]: FD 11 in non-blocking mode 2005.11.19 13:08:40 LOG7[3893:1024]: Cleaning up the signal pipe 2005.11.19 13:08:40 LOG7[3900:2050]: Connection from 66.149.103.32:3137 permitted by libwrap 2005.11.19 13:08:40 LOG5[3900:2050]: ssmtp connected from 66.149.103.32:3137 2005.11.19 13:08:40 LOG7[3900:2050]: SSL state (accept): before/accept initialization 2005.11.19 13:08:40 LOG7[3900:2050]: SSL state (accept): SSLv3 read client hello A 2005.11.19 13:08:40 LOG7[3900:2050]: SSL state (accept): SSLv3 write server hello A 2005.11.19 13:08:40 LOG7[3900:2050]: SSL state (accept): SSLv3 write certificate A 2005.11.19 13:08:40 LOG7[3900:2050]: SSL state (accept): SSLv3 write server done A 2005.11.19 13:08:40 LOG7[3900:2050]: SSL state (accept): SSLv3 flush data 2005.11.19 13:08:40 LOG7[3900:2050]: SSL state (accept): SSLv3 read client key exchange A 2005.11.19 13:08:40 LOG7[3900:2050]: SSL state (accept): SSLv3 read finished A 2005.11.19 13:08:40 LOG7[3900:2050]: SSL state (accept): SSLv3 write change cipher spec A 2005.11.19 13:08:40 LOG7[3900:2050]: SSL state (accept): SSLv3 write finished A 2005.11.19 13:08:40 LOG7[3900:2050]: SSL state (accept): SSLv3 flush data 2005.11.19 13:08:40 LOG7[3900:2050]: 2 items in the session cache 2005.11.19 13:08:40 LOG7[3900:2050]: 0 client connects (SSL_connect()) 2005.11.19 13:08:40 LOG7[3900:2050]: 0 client connects that finished 2005.11.19 13:08:40 LOG7[3900:2050]: 0 client renegotiatations requested 2005.11.19 13:08:40 LOG7[3900:2050]: 2 server connects (SSL_accept()) 2005.11.19 13:08:40 LOG7[3900:2050]: 2 server connects that finished 2005.11.19 13:08:40 LOG7[3900:2050]: 0 server renegotiatiations requested 2005.11.19 13:08:40 LOG7[3900:2050]: 0 session cache hits 2005.11.19 13:08:40 LOG7[3900:2050]: 2 session cache misses 2005.11.19 13:08:40 LOG7[3900:2050]: 0 session cache timeouts 2005.11.19 13:08:40 LOG6[3900:2050]: SSL accepted: new session negotiated 2005.11.19 13:08:40 LOG6[3900:2050]: Negotiated ciphers: RC4-MD5 SSLv3 Kx=RSA Au=RSA Enc=RC4(128) Mac=MD5 2005.11.19 13:08:40 LOG7[3900:2050]: FD 10 in non-blocking mode 2005.11.19 13:08:40 LOG7[3900:2050]: ssmtp connecting 10.10.10.30:25 2005.11.19 13:08:40 LOG7[3900:2050]: connect_wait: waiting 10 seconds 2005.11.19 13:08:40 LOG7[3900:2050]: connect_wait: connected 2005.11.19 13:08:40 LOG7[3900:2050]: Remote FD=10 initialized 2005.11.19 13:08:40 LOG7[3900:2050]: TCP_NODELAY option set on remote socket 2005.11.19 13:08:42 LOG7[3900:2050]: Socket closed on read 2005.11.19 13:08:42 LOG7[3900:2050]: SSL write shutdown 2005.11.19 13:08:42 LOG7[3900:2050]: SSL alert (write): warning: close notify 2005.11.19 13:08:42 LOG7[3900:2050]: SSL_shutdown retrying 2005.11.19 13:08:42 LOG7[3900:2050]: SSL doesn't need to read or write 2005.11.19 13:08:42 LOG7[3900:2050]: SSL socket closed on SSL_read 2005.11.19 13:08:42 LOG7[3900:2050]: Socket write shutdown 2005.11.19 13:08:42 LOG5[3900:2050]: Connection closed: 834 bytes sent to SSL, 1358 bytes sent to socket 2005.11.19 13:08:42 LOG7[3900:2050]: ssmtp finished (0 left) Without foreground, things do not continue past the first connection: 2005.11.19 13:10:32 LOG7[3910:1024]: ssmtp accepted FD=7 from 66.149.103.32:3268 2005.11.19 13:10:32 LOG7[3916:1026]: ssmtp started 2005.11.19 13:10:32 LOG7[3916:1026]: FD 7 in non-blocking mode 2005.11.19 13:10:32 LOG7[3916:1026]: TCP_NODELAY option set on local socket 2005.11.19 13:10:32 LOG7[3916:1026]: FD 10 in non-blocking mode 2005.11.19 13:10:32 LOG7[3916:1026]: FD 11 in non-blocking mode 2005.11.19 13:10:32 LOG7[3916:1026]: Connection from 66.149.103.32:3268 permitted by libwrap 2005.11.19 13:10:32 LOG5[3916:1026]: ssmtp connected from 66.149.103.32:3268 2005.11.19 13:10:32 LOG7[3916:1026]: SSL state (accept): before/accept initialization 2005.11.19 13:10:32 LOG7[3916:1026]: SSL state (accept): SSLv3 read client hello A 2005.11.19 13:10:32 LOG7[3916:1026]: SSL state (accept): SSLv3 write server hello A 2005.11.19 13:10:32 LOG7[3916:1026]: SSL state (accept): SSLv3 write certificate A 2005.11.19 13:10:32 LOG7[3916:1026]: SSL state (accept): SSLv3 write server done A 2005.11.19 13:10:32 LOG7[3916:1026]: SSL state (accept): SSLv3 flush data 2005.11.19 13:10:32 LOG7[3916:1026]: SSL state (accept): SSLv3 read client key exchange A 2005.11.19 13:10:32 LOG7[3916:1026]: SSL state (accept): SSLv3 read finished A 2005.11.19 13:10:32 LOG7[3916:1026]: SSL state (accept): SSLv3 write change cipher spec A 2005.11.19 13:10:32 LOG7[3916:1026]: SSL state (accept): SSLv3 write finished A 2005.11.19 13:10:32 LOG7[3916:1026]: SSL state (accept): SSLv3 flush data 2005.11.19 13:10:32 LOG7[3916:1026]: 1 items in the session cache 2005.11.19 13:10:32 LOG7[3916:1026]: 0 client connects (SSL_connect()) 2005.11.19 13:10:32 LOG7[3916:1026]: 0 client connects that finished 2005.11.19 13:10:32 LOG7[3916:1026]: 0 client renegotiatations requested 2005.11.19 13:10:32 LOG7[3916:1026]: 1 server connects (SSL_accept()) 2005.11.19 13:10:32 LOG7[3916:1026]: 1 server connects that finished 2005.11.19 13:10:32 LOG7[3916:1026]: 0 server renegotiatiations requested 2005.11.19 13:10:32 LOG7[3916:1026]: 0 session cache hits 2005.11.19 13:10:32 LOG7[3916:1026]: 1 session cache misses 2005.11.19 13:10:32 LOG7[3916:1026]: 0 session cache timeouts 2005.11.19 13:10:32 LOG6[3916:1026]: SSL accepted: new session negotiated 2005.11.19 13:10:32 LOG6[3916:1026]: Negotiated ciphers: RC4-MD5 SSLv3 Kx=RSA Au=RSA Enc=RC4(128) Mac=MD5 2005.11.19 13:10:32 LOG7[3916:1026]: FD 10 in non-blocking mode 2005.11.19 13:10:32 LOG7[3916:1026]: ssmtp connecting 10.10.10.30:25 2005.11.19 13:10:32 LOG7[3916:1026]: connect_wait: waiting 10 seconds 2005.11.19 13:10:32 LOG7[3916:1026]: connect_wait: connected 2005.11.19 13:10:32 LOG7[3916:1026]: Remote FD=10 initialized 2005.11.19 13:10:32 LOG7[3916:1026]: TCP_NODELAY option set on remote socket 2005.11.19 13:10:33 LOG7[3916:1026]: Socket closed on read 2005.11.19 13:10:33 LOG7[3916:1026]: SSL write shutdown 2005.11.19 13:10:33 LOG7[3916:1026]: SSL alert (write): warning: close notify 2005.11.19 13:10:33 LOG7[3916:1026]: SSL_shutdown retrying 2005.11.19 13:10:33 LOG7[3916:1026]: SSL doesn't need to read or write 2005.11.19 13:10:34 LOG7[3916:1026]: SSL socket closed on SSL_read 2005.11.19 13:10:34 LOG7[3916:1026]: Socket write shutdown 2005.11.19 13:10:34 LOG5[3916:1026]: Connection closed: 834 bytes sent to SSL, 1353 bytes sent to socket 2005.11.19 13:10:34 LOG7[3916:1026]: ssmtp finished (-1 left)

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Problem with Stunnel Working fine on the first connection and not on subsequent connections
by Kevin A. McGrail 19 Nov '05

19 Nov '05

Have worked on this all day without any glimmer of hope and would appreciate help and feedback! Regards, KAM # Description of your problem. What programs are on which machines, and how are they attempting to communicate. What connections are you attempting to secure in SSL. I am having problems with the regeneration of stunnel on an old but fairly reliable machine. I am switching from v3 to v4 and it works absolutely perfectly ONCE. The second time it just hangs. # What version of Stunnel you're using - remember, Stunnel 4.x doesn't take Stunnel 3.x command line options! 4.x # The list of parameters you are using for stunnel, and if you are running it standalone or from inetd/xinetd. I am running it in standalone. My conf file is: cert = /usr/local/ssl/certs/stunnel.pem key = /usr/local/ssl/certs/stunnel.pem chroot = /usr/local/var/stunnel/ setuid = nobody setgid = nobody pid = /stunnel.pid socket = l:TCP_NODELAY=1 socket = r:TCP_NODELAY=1 debug = 7 output = stunnel.log [ssmtp] accept = 465 connect = 10.10.10.30:25 # Output of "stunnel -f -D 7 <your-parameters>". Not sure this works on v4.X but here are the logs from the connection: 2005.11.18 19:17:56 LOG7[13166:1024]: ssmtp accepted FD=7 from 66.149.103.32:3542 2005.11.18 19:17:56 LOG7[13171:1026]: ssmtp started 2005.11.18 19:17:56 LOG7[13171:1026]: FD 7 in non-blocking mode 2005.11.18 19:17:56 LOG7[13171:1026]: TCP_NODELAY option set on local socket 2005.11.18 19:17:56 LOG7[13171:1026]: FD 10 in non-blocking mode 2005.11.18 19:17:56 LOG7[13171:1026]: FD 11 in non-blocking mode 2005.11.18 19:17:56 LOG7[13171:1026]: Connection from 66.149.103.32:3542 permitted by libwrap 2005.11.18 19:17:56 LOG5[13171:1026]: ssmtp connected from 66.149.103.32:3542 2005.11.18 19:17:56 LOG7[13171:1026]: SSL state (accept): before/accept initialization 2005.11.18 19:17:56 LOG7[13171:1026]: SSL state (accept): SSLv3 read client hello A 2005.11.18 19:17:56 LOG7[13171:1026]: SSL state (accept): SSLv3 write server hello A 2005.11.18 19:17:56 LOG7[13171:1026]: SSL state (accept): SSLv3 write certificate A 2005.11.18 19:17:56 LOG7[13171:1026]: SSL state (accept): SSLv3 write server done A 2005.11.18 19:17:56 LOG7[13171:1026]: SSL state (accept): SSLv3 flush data 2005.11.18 19:17:56 LOG7[13171:1026]: SSL state (accept): SSLv3 read client key exchange A 2005.11.18 19:17:56 LOG7[13171:1026]: SSL state (accept): SSLv3 read finished A 2005.11.18 19:17:56 LOG7[13171:1026]: SSL state (accept): SSLv3 write change cipher spec A 2005.11.18 19:17:56 LOG7[13171:1026]: SSL state (accept): SSLv3 write finished A 2005.11.18 19:17:56 LOG7[13171:1026]: SSL state (accept): SSLv3 flush data 2005.11.18 19:17:56 LOG7[13171:1026]: 1 items in the session cache 2005.11.18 19:17:56 LOG7[13171:1026]: 0 client connects (SSL_connect()) 2005.11.18 19:17:56 LOG7[13171:1026]: 0 client connects that finished 2005.11.18 19:17:56 LOG7[13171:1026]: 0 client renegotiatations requested 2005.11.18 19:17:56 LOG7[13171:1026]: 1 server connects (SSL_accept()) 2005.11.18 19:17:56 LOG7[13171:1026]: 1 server connects that finished 2005.11.18 19:17:56 LOG7[13171:1026]: 0 server renegotiatiations requested 2005.11.18 19:17:56 LOG7[13171:1026]: 0 session cache hits 2005.11.18 19:17:56 LOG7[13171:1026]: 1 session cache misses 2005.11.18 19:17:56 LOG7[13171:1026]: 0 session cache timeouts 2005.11.18 19:17:56 LOG6[13171:1026]: SSL accepted: new session negotiated 2005.11.18 19:17:56 LOG6[13171:1026]: Negotiated ciphers: RC4-MD5 SSLv3 Kx=RSA Au=RSA Enc=RC4(128) Mac=MD5 2005.11.18 19:17:56 LOG7[13171:1026]: FD 10 in non-blocking mode 2005.11.18 19:17:56 LOG7[13171:1026]: ssmtp connecting 10.10.10.30:25 2005.11.18 19:17:56 LOG7[13171:1026]: connect_wait: waiting 10 seconds 2005.11.18 19:17:56 LOG7[13171:1026]: connect_wait: connected 2005.11.18 19:17:56 LOG7[13171:1026]: Remote FD=10 initialized 2005.11.18 19:17:56 LOG7[13171:1026]: TCP_NODELAY option set on remote socket 2005.11.18 19:17:58 LOG7[13171:1026]: Socket closed on read 2005.11.18 19:17:58 LOG7[13171:1026]: SSL write shutdown 2005.11.18 19:17:58 LOG7[13171:1026]: SSL alert (write): warning: close notify 2005.11.18 19:17:58 LOG7[13171:1026]: SSL_shutdown retrying 2005.11.18 19:17:58 LOG7[13171:1026]: SSL doesn't need to read or write 2005.11.18 19:17:58 LOG7[13171:1026]: SSL socket closed on SSL_read 2005.11.18 19:17:58 LOG7[13171:1026]: Socket write shutdown 2005.11.18 19:17:58 LOG5[13171:1026]: Connection closed: 827 bytes sent to SSL, 1362 bytes sent to socket 2005.11.18 19:17:58 LOG7[13171:1026]: ssmtp finished (-1 left) There is nothing more after this point # Output of "stunnel -V". I think you want -version: /usr/local/sbin/stunnel -version stunnel 4.14 on i686-pc-linux-gnu PTHREAD+POLL+IPv4+LIBWRAP with OpenSSL 0.9.7e 25 Oct 2004 Global options cert = /usr/local/etc/stunnel/stunnel.pem ciphers = ALL:!ADH:+RC4:@STRENGTH debug = 5 key = /usr/local/etc/stunnel/stunnel.pem pid = /usr/local/var/stunnel/stunnel.pid RNDbytes = 64 RNDfile = /dev/urandom RNDoverwrite = yes session = 300 seconds verify = none Service-level options TIMEOUTbusy = 300 seconds TIMEOUTclose = 60 seconds TIMEOUTconnect = 10 seconds TIMEOUTidle = 43200 seconds # Output of "uname -a". Linux <removed> 2.2.26 #8 Fri Jul 16 00:42:34 EDT 2004 i686 unknown # Your libc version if you use Linux. 2.2.5 # Output of "gcc -v". Reading specs from /usr/lib/gcc-lib/i386-redhat-linux/egcs-2.91.66/specs gcc version egcs-2.91.66 19990314/Linux (egcs-1.1.2 release) # Output of "openssl version" or "ssleay version" depending on your library. Subscribe to stunnel-users. OpenSSL 0.9.7e 25 Oct 2004

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Stunnel Session Hangs
by Zachariah K Zachariah 17 Nov '05

17 Nov '05

Hi folks, I use stunnel-4.12 with openssl-0.9.7g to tunnel my CVS-pserver protocols. I have set up the local stunnel client to listen to port 22400 and to forward any connections on it to the cvs server that has the server side stunnel listening on port 22401 forwarding connections to the cvs-pserver on port 2401. Having set up thus, I can do a cvs login just fine. I can watch the negotiation happening using tcpdump. However when I try to check out a module from the repository, I see some files coming through but only to eventually hang. If I <Ctrl C> and try again, more files come in but hangs before the transaction is complete. I have to do this several time in order to download all the files to my local workspace. Upon checking the logs, I find that the hang occurs immediately after the message: 2005.10.28 14:21:53 LOG7[15095:67]: SSL_read returned WANT_READ: retrying 2005.10.28 14:21:53 LOG7[15095:67]: SSL_write returned WANT_WRITE: retrying 2005.10.28 14:21:53 LOG7[15095:67]: SSL_read returned WANT_READ: retrying I have included a snippet of the log file for reference. I have also included my stunnel.conf file. Sorry for the voluminous output. Can some one help me here? Thanks in advance. -ZZ ===============================STUNNEL.LOG================================== The full log file reads: 2005.10.28 14:20:44 LOG6[15095:64]: SSL accepted: previous session reused 2005.10.28 14:20:44 LOG7[15095:64]: FD 1 in non-blocking mode 2005.10.28 14:20:44 LOG7[15095:64]: smd-pserver connecting 127.0.0.1:2401 2005.10.28 14:20:44 LOG7[15095:64]: Remote FD=1 initialized 2005.10.28 14:20:44 LOG7[15095:64]: SSL_read returned WANT_READ: retrying 2005.10.28 14:20:44 LOG7[15095:64]: SSL_write returned WANT_WRITE: retrying 2005.10.28 14:20:44 LOG7[15095:64]: SSL_read returned WANT_READ: retrying 2005.10.28 14:20:50 LOG7[15095:64]: SSL alert (read): warning: close notify 2005.10.28 14:20:50 LOG7[15095:64]: SSL closed on SSL_read 2005.10.28 14:20:50 LOG7[15095:64]: Socket write shutdown 2005.10.28 14:20:50 LOG7[15095:64]: SSL write shutdown 2005.10.28 14:20:50 LOG7[15095:64]: SSL alert (write): warning: close notify 2005.10.28 14:20:50 LOG6[15095:64]: SSL_shutdown successfully sent close_notify 2005.10.28 14:20:50 LOG5[15095:64]: Connection closed: 73224 bytes sent to SSL, 4724 bytes sent to socket 2005.10.28 14:20:50 LOG7[15095:64]: smd-pserver finished (0 left) 2005.10.28 14:20:50 LOG5[15095:64]: stack_info: size=65536, current=5004 (7%), maximum=5004 (7%) 2005.10.28 14:20:50 LOG7[15095:64]: Context 64 closed 2005.10.28 14:20:51 LOG7[15095:1]: Context set: 64 (dropped) -> 1 2005.10.28 14:20:51 LOG7[15095:1]: Current context: 1 2005.10.28 14:20:51 LOG7[15095:1]: Releasing context 64 2005.10.28 14:20:51 LOG7[15095:1]: smd-pserver accepted FD=0 from 171.65.79.143:65521 2005.10.28 14:20:51 LOG7[15095:1]: Creating a new context 2005.10.28 14:20:51 LOG7[15095:1]: Context 65 created 2005.10.28 14:20:51 LOG7[15095:65]: Context swap: 1 -> 65 2005.10.28 14:20:51 LOG7[15095:65]: smd-pserver started 2005.10.28 14:20:51 LOG7[15095:65]: FD 0 in non-blocking mode 2005.10.28 14:20:51 LOG5[15095:65]: smd-pserver connected from 171.65.79.143:65521 2005.10.28 14:20:51 LOG7[15095:65]: SSL state (accept): before/accept initialization 2005.10.28 14:20:51 LOG7[15095:65]: SSL state (accept): SSLv3 read client hello A 2005.10.28 14:20:51 LOG7[15095:65]: SSL state (accept): SSLv3 write server hello A 2005.10.28 14:20:51 LOG7[15095:65]: SSL state (accept): SSLv3 write change cipher spec A 2005.10.28 14:20:51 LOG7[15095:65]: SSL state (accept): SSLv3 write finished A 2005.10.28 14:20:51 LOG7[15095:65]: SSL state (accept): SSLv3 flush data 2005.10.28 14:20:51 LOG7[15095:65]: SSL state (accept): SSLv3 read finished A 2005.10.28 14:20:51 LOG7[15095:65]: 6 items in the session cache 2005.10.28 14:20:51 LOG7[15095:65]: 0 client connects (SSL_connect()) 2005.10.28 14:20:51 LOG7[15095:65]: 0 client connects that finished 2005.10.28 14:20:51 LOG7[15095:65]: 0 client renegotiatations requested 2005.10.28 14:20:51 LOG7[15095:65]: 64 server connects (SSL_accept()) 2005.10.28 14:20:51 LOG7[15095:65]: 55 server connects that finished 2005.10.28 14:20:51 LOG7[15095:65]: 0 server renegotiatiations requested 2005.10.28 14:20:51 LOG7[15095:65]: 38 session cache hits 2005.10.28 14:20:51 LOG7[15095:65]: 0 session cache misses 2005.10.28 14:20:51 LOG7[15095:65]: 11 session cache timeouts 2005.10.28 14:20:51 LOG6[15095:65]: SSL accepted: previous session reused 2005.10.28 14:20:51 LOG7[15095:65]: FD 1 in non-blocking mode 2005.10.28 14:20:51 LOG7[15095:65]: smd-pserver connecting 127.0.0.1:2401 2005.10.28 14:20:51 LOG7[15095:65]: Remote FD=1 initialized 2005.10.28 14:20:51 LOG7[15095:65]: SSL_read returned WANT_READ: retrying 2005.10.28 14:20:51 LOG7[15095:65]: SSL_write returned WANT_WRITE: retrying 2005.10.28 14:20:51 LOG7[15095:65]: SSL_read returned WANT_READ: retrying 2005.10.28 14:20:57 LOG7[15095:65]: SSL alert (read): warning: close notify 2005.10.28 14:20:57 LOG7[15095:65]: SSL closed on SSL_read 2005.10.28 14:20:57 LOG7[15095:65]: Socket write shutdown 2005.10.28 14:20:57 LOG7[15095:65]: SSL write shutdown 2005.10.28 14:20:57 LOG7[15095:65]: SSL alert (write): warning: close notify 2005.10.28 14:20:57 LOG6[15095:65]: SSL_shutdown successfully sent close_notify 2005.10.28 14:20:57 LOG5[15095:65]: Connection closed: 73224 bytes sent to SSL, 4724 bytes sent to socket 2005.10.28 14:20:57 LOG7[15095:65]: smd-pserver finished (0 left) 2005.10.28 14:20:57 LOG5[15095:65]: stack_info: size=65536, current=5004 (7%), maximum=5004 (7%) 2005.10.28 14:20:57 LOG7[15095:65]: Context 65 closed 2005.10.28 14:20:58 LOG7[15095:1]: Context set: 65 (dropped) -> 1 2005.10.28 14:20:58 LOG7[15095:1]: Current context: 1 2005.10.28 14:20:58 LOG7[15095:1]: Releasing context 65 2005.10.28 14:20:58 LOG7[15095:1]: smd-pserver accepted FD=0 from 171.65.79.143:65523 2005.10.28 14:20:58 LOG7[15095:1]: Creating a new context 2005.10.28 14:20:58 LOG7[15095:1]: Context 66 created 2005.10.28 14:20:58 LOG7[15095:66]: Context swap: 1 -> 66 2005.10.28 14:20:58 LOG7[15095:66]: smd-pserver started 2005.10.28 14:20:58 LOG7[15095:66]: FD 0 in non-blocking mode 2005.10.28 14:20:58 LOG5[15095:66]: smd-pserver connected from 171.65.79.143:65523 2005.10.28 14:20:58 LOG7[15095:66]: SSL state (accept): before/accept initialization 2005.10.28 14:20:58 LOG7[15095:66]: SSL state (accept): SSLv3 read client hello A 2005.10.28 14:20:58 LOG7[15095:66]: SSL state (accept): SSLv3 write server hello A 2005.10.28 14:20:58 LOG7[15095:66]: SSL state (accept): SSLv3 write change cipher spec A 2005.10.28 14:20:58 LOG7[15095:66]: SSL state (accept): SSLv3 write finished A 2005.10.28 14:20:58 LOG7[15095:66]: SSL state (accept): SSLv3 flush data 2005.10.28 14:20:58 LOG7[15095:66]: SSL state (accept): SSLv3 read finished A 2005.10.28 14:20:58 LOG7[15095:66]: 6 items in the session cache 2005.10.28 14:20:58 LOG7[15095:66]: 0 client connects (SSL_connect()) 2005.10.28 14:20:58 LOG7[15095:66]: 0 client connects that finished 2005.10.28 14:20:58 LOG7[15095:66]: 0 client renegotiatations requested 2005.10.28 14:20:58 LOG7[15095:66]: 65 server connects (SSL_accept()) 2005.10.28 14:20:58 LOG7[15095:66]: 56 server connects that finished 2005.10.28 14:20:58 LOG7[15095:66]: 0 server renegotiatiations requested 2005.10.28 14:20:58 LOG7[15095:66]: 39 session cache hits 2005.10.28 14:20:58 LOG7[15095:66]: 0 session cache misses 2005.10.28 14:20:58 LOG7[15095:66]: 11 session cache timeouts 2005.10.28 14:20:58 LOG6[15095:66]: SSL accepted: previous session reused 2005.10.28 14:20:58 LOG7[15095:66]: FD 1 in non-blocking mode 2005.10.28 14:20:58 LOG7[15095:66]: smd-pserver connecting 127.0.0.1:2401 2005.10.28 14:20:58 LOG7[15095:66]: Remote FD=1 initialized 2005.10.28 14:20:58 LOG7[15095:66]: SSL_read returned WANT_READ: retrying 2005.10.28 14:20:58 LOG7[15095:66]: SSL_write returned WANT_WRITE: retrying 2005.10.28 14:20:58 LOG7[15095:66]: SSL_read returned WANT_READ: retrying 2005.10.28 14:21:50 LOG7[15095:66]: SSL alert (read): warning: close notify 2005.10.28 14:21:50 LOG7[15095:66]: SSL closed on SSL_read 2005.10.28 14:21:50 LOG7[15095:66]: Socket write shutdown 2005.10.28 14:21:50 LOG7[15095:66]: SSL write shutdown 2005.10.28 14:21:50 LOG7[15095:66]: SSL alert (write): warning: close notify 2005.10.28 14:21:50 LOG6[15095:66]: SSL_shutdown successfully sent close_notify 2005.10.28 14:21:50 LOG5[15095:66]: Connection closed: 73224 bytes sent to SSL, 4724 bytes sent to socket 2005.10.28 14:21:50 LOG7[15095:66]: smd-pserver finished (0 left) 2005.10.28 14:21:50 LOG5[15095:66]: stack_info: size=65536, current=5004 (7%), maximum=5004 (7%) 2005.10.28 14:21:50 LOG7[15095:66]: Context 66 closed 2005.10.28 14:21:52 LOG7[15095:1]: Context set: 66 (dropped) -> 1 2005.10.28 14:21:52 LOG7[15095:1]: Current context: 1 2005.10.28 14:21:52 LOG7[15095:1]: Releasing context 66 2005.10.28 14:21:52 LOG7[15095:1]: smd-pserver accepted FD=0 from 171.65.79.143:65525 2005.10.28 14:21:52 LOG7[15095:1]: Creating a new context 2005.10.28 14:21:52 LOG7[15095:1]: Context 67 created 2005.10.28 14:21:52 LOG7[15095:67]: Context swap: 1 -> 67 2005.10.28 14:21:52 LOG7[15095:67]: smd-pserver started 2005.10.28 14:21:52 LOG7[15095:67]: FD 0 in non-blocking mode 2005.10.28 14:21:52 LOG5[15095:67]: smd-pserver connected from 171.65.79.143:65525 2005.10.28 14:21:52 LOG7[15095:67]: SSL state (accept): before/accept initialization 2005.10.28 14:21:52 LOG7[15095:67]: SSL state (accept): SSLv3 read client hello A 2005.10.28 14:21:52 LOG7[15095:67]: SSL state (accept): SSLv3 write server hello A 2005.10.28 14:21:52 LOG7[15095:67]: SSL state (accept): SSLv3 write change cipher spec A 2005.10.28 14:21:52 LOG7[15095:67]: SSL state (accept): SSLv3 write finished A 2005.10.28 14:21:52 LOG7[15095:67]: SSL state (accept): SSLv3 flush data 2005.10.28 14:21:52 LOG7[15095:67]: SSL state (accept): SSLv3 read finished A 2005.10.28 14:21:52 LOG7[15095:67]: 6 items in the session cache 2005.10.28 14:21:52 LOG7[15095:67]: 0 client connects (SSL_connect()) 2005.10.28 14:21:52 LOG7[15095:67]: 0 client connects that finished 2005.10.28 14:21:52 LOG7[15095:67]: 0 client renegotiatations requested 2005.10.28 14:21:52 LOG7[15095:67]: 66 server connects (SSL_accept()) 2005.10.28 14:21:52 LOG7[15095:67]: 57 server connects that finished 2005.10.28 14:21:52 LOG7[15095:67]: 0 server renegotiatiations requested 2005.10.28 14:21:52 LOG7[15095:67]: 40 session cache hits 2005.10.28 14:21:52 LOG7[15095:67]: 0 session cache misses 2005.10.28 14:21:52 LOG7[15095:67]: 11 session cache timeouts 2005.10.28 14:21:52 LOG6[15095:67]: SSL accepted: previous session reused 2005.10.28 14:21:52 LOG7[15095:67]: FD 1 in non-blocking mode 2005.10.28 14:21:52 LOG7[15095:67]: smd-pserver connecting 127.0.0.1:2401 2005.10.28 14:21:52 LOG7[15095:67]: Remote FD=1 initialized 2005.10.28 14:21:53 LOG7[15095:67]: SSL_read returned WANT_READ: retrying 2005.10.28 14:21:53 LOG7[15095:67]: SSL_write returned WANT_WRITE: retrying 2005.10.28 14:21:53 LOG7[15095:67]: SSL_read returned WANT_READ: retrying ========================================================================== =========================STUNNEL.CONF====================================== ; Sample stunnel configuration file by Michal Trojnara 2002-2005 ; Some options used here may not be adequate for your particular configuration ; Please make sure you understand them (especially the effect of chroot jail) ;Delay DNS Lookups delay = yes ; Certificate/key is needed in server mode and optional in client mode cert = /tools/stunnel/4.12/etc/stunnel/stunnel.pem ;key = /tools/stunnel/4.12/etc/stunnel/mail.pem ; Some security enhancements for UNIX systems - comment them out on Win32 chroot = /tools/stunnel/4.12/var/stunnel/ setuid = cvsadmin setgid = cvs ; PID is created inside chroot jail pid = /stunnel.pid ; Some performance tunings socket = l:TCP_NODELAY=1 socket = r:TCP_NODELAY=1 ;compression = rle ; Workaround for Eudora bug ;options = DONT_INSERT_EMPTY_FRAGMENTS ; Authentication stuff ;verify = 2 ; Don't forget to c_rehash CApath; CApath is located inside chroot jail: ;CApath = /certs ; It's often easier to use CAfile: ;CAfile = /tools/stunnel/4.12/etc/stunnel/certs.pem ; Don't forget to c_rehash CRLpath; CRLpath is located inside chroot jail: ;CRLpath = /crls ; Alternatively you can use CRLfile: ;CRLfile = /tools/stunnel/4.12/etc/stunnel/crls.pem ; Some debugging stuff useful for troubleshooting debug = 7 output = /tools/stunnel/current/var/stunnel/stunnel.log ; Use it for client mode ;client = yes ; Service-level configuration ;[pop3s] ;accept = 995 ;connect = 110 ;[imaps] ;accept = 993 ;connect = 143 ;[ssmtp] ;accept = 465 ;connect = 25 [pserver] accept = 22401 connect = 2401 TIMEOUTclose = 30 ; vim:ft=dosini

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