June 2018 - stunnel-users

stunnel FIPS mode 140-2/ Other Modes
by mehmet ozisik 19 Sep '25

19 Sep '25

Hi All, I would like to ask a question about stunnel fips mode. There are lots of question and answers on the internet related with this, but I could not find any answer related with mine. I am compiling with openssl (auto detecting fips) . Here is a part of confgiure output : checking for FIPS_mode_set... yes configure: FIPS mode detected So I am thinking that fips also is being included. Then I try to run stunnel on target platform (in stunnel.conf fips=yes) and it gives below error : Compiled/running with OpenSSL 0.9.8w-fips 23 Apr 2012 Threading:PTHREAD Sockets:POLL,IPv6 SSL:ENGINE,OCSP,FIPS Reading configuration from file stunnel.conf FIPS_mode_set: 2D06906E: error:2D06906E:FIPS routines:FIPS_CHECK_INCORE_FINGERPRINT:fingerprint does not match there are lots of information about this errror on internet. Then when I configure stunnel.conf with fips=no, stunnel is running successfully. I know that fips=yes means that enables FIPS 140-2 mode and I guess my fips canister does not supoort fips 140-2 mode (I do not know which fips mode it has supported). Now my question is coming : When I set fips=no, stunnel also starts with other available fips modes which the canister included? Or it skips running fips mode completely? Plase inform me if anyone has any idea? Regards

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Requests to cloud server that requires host header
by Lorne Kates 13 Nov '24

13 Nov '24

(related to Akamai message from before-- but I have better troubleshooting information). I'm tying to route traffic through stunnel to a "cloud" based-endpoint. That endpoint has a static server name-- test.authorize.net. (This is the dev sandbox for auth.net) But if you do an nslookup on test.authorize.net, you'll get back a different servername and IP, because it's so wonderfully "cloud". Stunnel apparently tries to connect to the nslookup value. The server rejects the request because it can't route it back to test.authorize.net. I've tried adding "delay = yes" and "sni = test.authorize.net", but neither work. To see this in action, a simple setup with any accept, then connect to test.authorize.net:443 in client = yes mode. This is what a valid response looks like (13 -- give me the darn merchant ID in a POST): https://test.authorize.net/gateway/transact.dll This is what you'll get if you try to use stunnel (400 invalid url) : https://23.195.204.150/gateway/transact.dll So how can I get stunnel to send the proper Request Header (host: test.authorize.net) make sure it's using http/1.1, etc?

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Stunnel 4 failing to connect to gmail
by Asif Iqbal 11 Dec '20

11 Dec '20

I am faling to connect to gmail. Not sure what that bind error means. iqbala@ghar:~$ sudo stunnel4 2008.12.15 13:53:17 LOG7[3839:3083650736]: Snagged 64 random bytes from /home/iqbala/.rnd 2008.12.15 13:53:17 LOG7[3839:3083650736]: Wrote 1024 new random bytes to /home/iqbala/.rnd 2008.12.15 13:53:17 LOG7[3839:3083650736]: RAND_status claims sufficient entropy for the PRNG 2008.12.15 13:53:17 LOG7[3839:3083650736]: PRNG seeded successfully 2008.12.15 13:53:17 LOG7[3839:3083650736]: Certificate: /etc/stunnel/stunnel.pem 2008.12.15 13:53:17 LOG7[3839:3083650736]: Certificate loaded 2008.12.15 13:53:17 LOG7[3839:3083650736]: Key file: /etc/stunnel/stunnel.pem 2008.12.15 13:53:17 LOG7[3839:3083650736]: Private key loaded 2008.12.15 13:53:17 LOG7[3839:3083650736]: SSL context initialized for service ssmtp 2008.12.15 13:53:17 LOG5[3839:3083650736]: stunnel 4.22 on i486-pc-linux-gnu with OpenSSL 0.9.8g 19 Oct 2007 2008.12.15 13:53:17 LOG5[3839:3083650736]: Threading:PTHREAD SSL:ENGINE Sockets:POLL,IPv6 Auth:LIBWRAP 2008.12.15 13:53:17 LOG6[3839:3083650736]: file ulimit = 1024 (can be changed with 'ulimit -n') 2008.12.15 13:53:17 LOG6[3839:3083650736]: poll() used - no FD_SETSIZE limit for file descriptors 2008.12.15 13:53:17 LOG5[3839:3083650736]: 500 clients allowed 2008.12.15 13:53:17 LOG7[3839:3083650736]: FD 10 in non-blocking mode 2008.12.15 13:53:17 LOG7[3839:3083650736]: FD 11 in non-blocking mode 2008.12.15 13:53:17 LOG7[3839:3083650736]: FD 12 in non-blocking mode 2008.12.15 13:53:17 LOG7[3839:3083650736]: SO_REUSEADDR option set on accept socket 2008.12.15 13:53:17 LOG3[3839:3083650736]: Error binding ssmtp to 74.125.93.111:587 2008.12.15 13:53:17 LOG3[3839:3083650736]: bind: Cannot assign requested address (99) Here is how my conf file looks like iqbala@ghar:~$ cat /etc/stunnel/stunnel.conf | egrep -v "^;|^$" cert = /etc/stunnel/stunnel.pem foreground = yes sslVersion = SSLv3 chroot = /var/lib/stunnel4/ setuid = stunnel4 setgid = stunnel4 pid = /stunnel4.pid socket = l:TCP_NODELAY=1 socket = r:TCP_NODELAY=1 debug = 7 output = /var/log/stunnel4/stunnel.log client = yes [ssmtp] accept = smtp.gmail.com:587 connect = 25 Asif Iqbal PGP Key: 0xE62693C5 KeyServer: pgp.mit.edu

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Stunnel & Gmail security
by BOXI31 TEST 16 Oct '20

16 Oct '20

Hi all, To make "Stunnel 5.31" work with Gmail, I have to go in security settings of Gmail and "allow less secure apps to access my account". Is it mandatory ? Is it possible to set Stunnel to access Gmail without lowering it security level ? How ? I checked in log file TLS v1.2 is used by Stunnel but Gmail still consider it as a "less secure app." ! Regards, Steve

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tls question
by Daniel Trickett 02 Jul '18

02 Jul '18

Hi, If I use stunnel 5.44, how do I know that the protocol being used is TLS1.2? Is it the default? Working with supplier sites which still accept 1.0/1.1, but want to make sure that I am using 1.2, as they will be disabling the older protocols. Thanks and Best regards, Dan This message and any attachment are confidential and may be privileged or otherwise protected from disclosure. If you are not the intended recipient, you must not copy this message or attachment or disclose the contents to any other person. If you have received this transmission in error, please notify the sender immediately and delete the message and any attachment from your system. Merck KGaA, Darmstadt, Germany and any of its subsidiaries do not accept liability for any omissions or errors in this message which may arise as a result of E-Mail-transmission or for damages resulting from any unauthorized changes of the content of this message and any attachment thereto. Merck KGaA, Darmstadt, Germany and any of its subsidiaries do not guarantee that this message is free of viruses and does not accept liability for any damages caused by any virus transmitted therewith. Click http://www.emdgroup.com/emd/imprint/mail_disclaimer.html to access the German, French, Spanish and Portuguese versions of this disclaimer.

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Potentially dangerous change of behavior in handling "global option" in stunnel after version 5.45
by Tony Cheneau 29 Jun '18

29 Jun '18

Hello everyone, I was updating my version of stunnel and playing my regression suite and I was surprised to see some tests fail. We usually apply "verify = 2" as global option at the beginning of the configuration file on our stunnel "server" so as to enforce the client certificate verification. So I was a little bit surprise to see I could establish a TLS connection with my test server without providing a client certificate. The "verify = 2" as a "global option" is parsed at some point, because I can trigger an error message if I place a bogus value ("verify = 8"). Yet, it seems to be ignored when accepting connections. If I move the "verify = 2" from the "global option" to a service-level option for a specific service/tunnel, it works as expected (and documented): it rejects my certificate-less client. After a little bit of investigation, I was able to narrow down the change of behavior in version 5.45 (meaning that 5.44 still follow the old behavior). All the newer version follow this new behavior. I haven't seen any public CVS/SVN/git for stunnel, so I was not able to narrow it down further and I could not identify the exact change in the code that modified the behavior. While I understand that this option is documented in the manpage as a service-level option, in practice, "verify" could be used as a global option for years (my oldest documented usage at my company dates back from stunnel 4.54). (I know this option is going to be replaced by verifyChain/requireCert, the observed behavior reported in this email also applies on these options: they can't be applied program wide as a "global option") Am I missing something obvious here ? I haven't seen the change documented in the changelog, so it looks like a regression to me. Thank you in advance (and thank you for the great piece of software, obviously!). Regards, Tony Cheneau

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Re: [stunnel-users] stunnel 5.47 released
by Eric S Eberhard 28 Jun '18

28 Jun '18

Query -- how does this relate to TLSv1.3 and the alpha version (which is not going to work with the final version -- and does not exist I think) -- and what version of openssl do you recommend? Thanks, Eric Eric S Eberhard VICS (Vertical Integrated Computer Systems) Voice: 928 567 3529 Cell : 928 301 7537 (not reliable except for text or if not home) 2933 W Middle Verde Rd Camp Verde, AZ 86322 -----Original Message----- From: stunnel-users [mailto:stunnel-users-bounces@stunnel.org] On Behalf Of Michal Trojnara Sent: Friday, June 22, 2018 11:10 PM To: stunnel-users(a)stunnel.org; stunnel-announce(a)stunnel.org; openssl-users(a)openssl.org Subject: [stunnel-users] stunnel 5.47 released Dear Users, I have released version 5.47 of stunnel. Version 5.47, 2018.06.23, urgency: HIGH * New features - Fast add_lock_callback for OpenSSL < 1.1.0. This largely improves performance on heavy load. - Automatic detection of Homebrew OpenSSL. - Clarified port binding error logs. - Various "make test" improvements. * Bugfixes - Fixed a crash on switching to SNI slave sections. Home page: https://www.stunnel.org/ Download: https://www.stunnel.org/downloads.html SHA-256 hashes: c4e675db996eb92beef885f72a3ed8af3c7603fea6b99d2873198dd6c0021d0b stunnel-5.47.tar.gz 985e1d65a3f4a7599cc78630960e1b2c97981f91ce6bc41f2eefcd371b4067a3 stunnel-5.47-win32-installer.exe 309cfb79329448f0c134aece0d10d0737e3728b25c288e9a76650837cd6f839c stunnel-5.47-android.zip Best regards, Mike

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question regarding TLS connection.
by Daniel Trickett 26 Jun '18

26 Jun '18

Hi We are using stunnel 5.44. We are having an issue connecting with a customer who is not supporting TLS 1.1, only 1.2 and 1.3. When I look in the log, I see the following. Why do I see the SSLv3 note in the line? The below leads me to believe that we connect to the customer, but they say that we are not. 2018.06.25 11:37:24 LOG7[7]: TLS state (connect): SSLv3 read server certificate A 2018.06.25 11:37:24 LOG6[7]: Client certificate not requested 2018.06.25 11:37:24 LOG7[7]: TLS state (connect): SSLv3 read server done A 2018.06.25 11:37:24 LOG7[7]: TLS state (connect): SSLv3 write client key exchange A 2018.06.25 11:37:24 LOG7[7]: TLS state (connect): SSLv3 write change cipher spec A 2018.06.25 11:37:24 LOG7[7]: TLS state (connect): SSLv3 write finished A 2018.06.25 11:37:24 LOG7[7]: TLS state (connect): SSLv3 flush data 2018.06.25 11:37:24 LOG7[7]: TLS state (connect): SSLv3 read finished A 2018.06.25 11:37:24 LOG7[7]: 1 client connect(s) requested 2018.06.25 11:37:24 LOG7[7]: 1 client connect(s) succeeded 2018.06.25 11:37:24 LOG7[7]: 0 client renegotiation(s) requested 2018.06.25 11:37:24 LOG7[7]: 0 session reuse(s) 2018.06.25 11:37:24 LOG6[7]: TLS connected: new session negotiated Best regards, Dan Daniel Trickett Head of Database Services | MBS Business Technology BX-TCS-O Oracle ERP Business Services of Merck KGaA, Darmstadt, Germany Planned Absence - 7/2/2018 - 7/6/2018 MilliporeSigma A business of Merck KGaA, Darmstadt, Germany EMD Millipore Corporation | 80 Ashby Road | Bedford, MA 01730 | USA office 781-533-3017 |cell 978-761-3506 |email daniel.trickett(a)emdmillipore.com<mailto:daniel.trickett@emdmillipore.com> This message and any attachment are confidential and may be privileged or otherwise protected from disclosure. If you are not the intended recipient, you must not copy this message or attachment or disclose the contents to any other person. If you have received this transmission in error, please notify the sender immediately and delete the message and any attachment from your system. Merck KGaA, Darmstadt, Germany and any of its subsidiaries do not accept liability for any omissions or errors in this message which may arise as a result of E-Mail-transmission or for damages resulting from any unauthorized changes of the content of this message and any attachment thereto. Merck KGaA, Darmstadt, Germany and any of its subsidiaries do not guarantee that this message is free of viruses and does not accept liability for any damages caused by any virus transmitted therewith. Click http://www.emdgroup.com/emd/imprint/mail_disclaimer.html to access the German, French, Spanish and Portuguese versions of this disclaimer.

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stunnel 5.47 released
by Michal Trojnara 23 Jun '18

23 Jun '18

Dear Users, I have released version 5.47 of stunnel. Version 5.47, 2018.06.23, urgency: HIGH * New features - Fast add_lock_callback for OpenSSL < 1.1.0. This largely improves performance on heavy load. - Automatic detection of Homebrew OpenSSL. - Clarified port binding error logs. - Various "make test" improvements. * Bugfixes - Fixed a crash on switching to SNI slave sections. Home page: https://www.stunnel.org/ Download: https://www.stunnel.org/downloads.html SHA-256 hashes: c4e675db996eb92beef885f72a3ed8af3c7603fea6b99d2873198dd6c0021d0b stunnel-5.47.tar.gz 985e1d65a3f4a7599cc78630960e1b2c97981f91ce6bc41f2eefcd371b4067a3 stunnel-5.47-win32-installer.exe 309cfb79329448f0c134aece0d10d0737e3728b25c288e9a76650837cd6f839c stunnel-5.47-android.zip Best regards, Mike

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Stunnel 5.45 and 5.46 crashes upon reconnect HTTPS
by Javier 22 Jun '18

22 Jun '18

Hi, isn't annoying when you are using an old version, 5.44, and all goes fine, you notice you are outdated and then comes the problems after update? :-P The thing is that yesterday I needed the HTTPS server so I run Stunnel 5.44 for my non-SSL app and all was fine. I updated to 5.46 just because I forgot the last time and didn't even run again because I didn't need it. Today I used it and... I had a crash. I tested 5.45 to trace versions back, and it crashes as well. Back to 5.44 and no crash. The crash happens when there is a reload/reconnect/multiconnect (example, 2 connections html+images) by the browser when connects to an HTTPS server. It only happens when using a SNI service. I've been able to trace back the log on those versions and when fails in 5.45 and 5.46 is at the time when it needs to switch to the SNI service. (log from 5.44) SNI: requested servername: xxx SNI: matched pattern: xxx SNI: switched to service [xxx] <<<<----- BEFORE SWITCH, IT CRASHES on 5.45 and 5.46 Imagine you load https://xxx/. The first time is fine, the second, crashes stunnel. Not happening with 5.44. I haven't seen any change to SNI in manual so... :-? These are the configs for the used virtual servers. Nothing has been changed, anyway: [SSL] client = no accept = y.y.y.1:4747 connect = y.y.y.2:443 [SSL-xxx-SNI] client = no sni = SSL:xxx connect = y.y.y.2:443 cert = pem key = pem Don't mind the port numbers. They aren't in conflict. Running on Windows 2000. Regards.

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