October 2013 - 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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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 and hosts.allow
by Yousef Alhashemi 05 Jul '16

05 Jul '16

Hi, This may be a little bit off-topic, but does anyone here use stunnel with pan? My connections to stunnel (in pan) are always refused by libwrap. I was looking for the right rule to add to /etc/hosts.allow but nothing seems to work aside from "ALL : ALL" (which is obviously not good) and "nntps: KNOWN". Is the latter reasonable? The hosts_access(5) manpage is confusing to say the least. It mentions that daemon (the first token on any line) is the name of the daemon running the process, which would be "stunnel" in my case, but using "stunnel : LOCAL" or even "stunnel : ALL" doesn't work. The rule that seems to work, as mentioned, is "nntps : KNOWN" ("nntps" being the group name in stunnel.conf). What's even more confusing to me is that "nntps : LOCAL" does not work either. Nor does "nntps : localhost 127.0.0.1", "nntps : localhost", "nntps : 127.0.0.1", or "nntps : 192.168.1.". Pan is running on the same machine as stunnel so all connections must be coming from localhost. Why do these rules not trigger? Either way, I'd like to know the "least permissive" hosts.allow rule that would allow me to connect to my news provider from pan, and/or whether "nntps : KNOWN" is a safe option. Thanks, Yousef

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Hostname verification, support for, and patches
by fslama＠comcast.net 06 Dec '13

06 Dec '13

After scouring the net I've found several isolated discussions regarding stunnel hostname validation. And also some patches that seem to implement hostname validation: https://www.stunnel.org/pipermail/stunnel-users/2010-March/002613.html I have a requirement to have stunnel (4.56) validate client certificates and their identity by comparing the its CNAME against the source address. I recall reading one response (which I can't find at the moment) from Marzena Trojnara indicating that this feature won't be supported. If so, can you explain the rational? Are there sanctioned patches out there today? Regards, -Fred

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Trouble sending email via smtp with a particular gmail address
by Brian Morgan 01 Nov '13

01 Nov '13

I'm having trouble sending email through stunnel with our customer service email address. We use google premium services for our hosted email. I can send through stunnel using my own personal account, but when I switch to the cust service account, I get the error: "Failed to send an E-mail through the specified SMTP server [127.0.0.1]: The SMTP server requires a secure connection or the client was not authenticated. The server response was 5.5.1 Authentication Required." And yes, I double/triple checked credentials and can login through the gmail interface with them just fine. I also tried changing the password to a strong password which did not help. gmail settings in stunnel.conf: [gmail-smtp] client = yes accept = 127.0.0.1:259 connect = smtp.gmail.com:465 I also tried port 587 but that produces another error: "Failed to send an E-mail through the specified SMTP server [127.0.0.1]: Failure sending mail." Any ideas?

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Question Regarding Client Installer
by Andrew Smith 29 Oct '13

29 Oct '13

We currently use Stunnel to allow our clients to connect to their Databases that are hosted by us. I think this product is great. However, I am a newbie to Stunnel as our previous resource has passed away. What I would like to know now to do is create an installer for clients machines that have the correct configuration files in etc... I am sure this is pretty easy and I will be able to do it this once I am guided in the correct direction. Thanks in advance! ________________________________ Andrew Smith Support Technical Services Analyst P: 614-875-4910 x109 F: 614-875-4088 E: andrew.smith(a)harriscomputer.com [http://www.harriscomputer.com/images/signatures/HarrisSchools.jpg] [http://www.harriscomputer.com/images/signatures/DivisionofHarris.gif]<http://www.harriscomputer.com/> 6110 Enterprise Parkway Grove City, OH 43123 www.harris-schoolsolutions.com<http://www.harris-schoolsolutions.com> This message is intended exclusively for the individual or entity to which it is addressed. This communication may contain information that is proprietary, privileged or confidential or otherwise legally exempt from disclosure. If you are not the named addressee, you are not authorized to read, print, retain, copy or disseminate this message or any part of it. If you have received this message in error, please notify the sender immediately by e-mail and delete all copies of the message.

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Re: [stunnel-users] Is it usual/recommended to have key and cert in ONE stunnel.pem file?
by Ben Stover 29 Oct '13

29 Oct '13

Hello John, thank you for your clarification. Two more additional questions: According to stunnel guide I created a cert + key with the following command: openssl.exe req -new -x509 -days 3650 -nodes -config stunnel.cnf -out stunnelcert.pem -keyout stunnelkey.pem 1.) For what do I need here the -config stunnel.cnf parameter? I am prompted by openssl for the content values during generation anyway. Can stunnel.cnf be seen only as a default value pattern for the created cert during generation? Can I omit this parameter? 2.) After creation of cert+key I have to specify them (as client) in stunnel.conf (with "o") as follows: cert = stunnelcert.pem key = stunnelkey.pem Is this sufficient? Thank you Ben On Mon, Oct 28, 2013 at 06:39:15PM +0100, Ben Stover wrote: > According to some tutorial pages I generated with OpenSSL a (selfsigned) certificate. > > This file stunnel.pem contains the certifictae as well as the private key. > > Is this usual/recommended? Hello John, That sort of falls into the "tragedy waiting to happen" category. The certificate is supposed to be given to clients, and the key belongs to the server and has to be kept private or there's really no point in using SSL. > Or should user put these two parts in two independent files? Yes, absolutely. In fact I suppose you're using Windows or went through some hoop-jumping to combine them, because in "normal" OpenSSL usage the key is generated first and then the certs are requested and signed by the CA (or selfsigning) key. /jl

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VPAT Section 508 Compliance
by Tracy Drake - QI-C 28 Oct '13

28 Oct '13

Hello Stunnel Support! I am seeking a VPAT showing the level Sec 508 compliance so that we can move toward making Stunnel a GSA-approved software. I guess the biggest question is whether or not Stunnel is considered to be section 508 compliant. Please advise as to where/how I can obtain this information. -- Tracy Drake CSM Senior Consultant GSA-FAS FAME Contractor URSA & INFOConnect Support & Training Team Lead 704-987-1211 tracy.drake(a)gsa.gov

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Is it usual/recommended to have key and cert in ONE stunnel.pem file?
by Ben Stover 28 Oct '13

28 Oct '13

According to some tutorial pages I generated with OpenSSL a (selfsigned) certificate. This file stunnel.pem contains the certifictae as well as the private key. Is this usual/recommended? Or should user put these two parts in two independent files? Ben

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Is "fips=no" recommended?
by Ben Stover 25 Oct '13

25 Oct '13

I stunnel.conf there is a parameter fips=no which is currently commented out here. Is it (resp. when is it) recommended to activate this parameter? Ben

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