August 2012 - stunnel-users

Stunnel 4 failing to connect to gmail
by Asif Iqbal 10 Dec '20

10 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

5 9

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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SSL renegotiation patch
by Janusz Dziemidowicz 19 Sep '12

19 Sep '12

Hi, since I couldn't find a better place I'm sending a simple patch that allows to disable SSL renegotiation here. Possible reasons for this: - famous renegotiation SSL flaw, patched in OpenSSL a long time ago, but not everyone can or want to upgrade OpenSSL - renegotiation makes some DoS attacks much easier (see http://www.thc.org/thc-ssl-dos/) regardless of it being a secure one or not - it is really not needed in many cases The approach is based on what is being done in Apache. The default is to allow renegotation, so there should be no surprises for anyone after upgrade. Patch applies on latest (4.54b4) stunnel beta. Feel free to comment:) -- Janusz Dziemidowicz

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MySQL replication + SSL/stunnel
by Gareth Evans 27 Aug '12

27 Aug '12

Hello, I'm failing miserably to implement replication over any kind of SSL (that is, MySQL's native (alleged) SSL support) or stunnel. I'd be grateful for any tips or advice. I have tried using OpenSSL and MySQL in various flavours: CentOS 6.2, OpenSSL v1.0.0, MySQL v5.1.63 Ubuntu 12.04, OpenSSL v1.0.1, MySQL v 5.5.24 and stunnel4 on both - certs created with OpenSSL in each case. I get an eror 1045 access denied from the MySQL native SSL approach, and mysql -u ejbkslave -pejbkslavepw -h127.0.0.1 -P3307 ERROR 2013 (HY000): Lost connection to MySQL server at 'reading initial communication packet', system error: 104 from stunnel (connecting two Ubuntu 12.04 VM's on my PC, with the latest updates) - if you know what causes this error and/or could point me towards some good documentation, I'd be grateful. I've copied and amended stunnel.conf-sample and just added debug and accept/connect info in each case. I've seen various reports around the web that OpenSSL+MySQL don't work together at the moment, but it seems some people can repicate the problem while others can't - I've tried the previous version of OpenSSL (1.0.0e on Ubuntu) still without success. Most frustrating!! Thanks Gareth

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Stunnel performance about multiple session
by Yuqiong Sun 26 Aug '12

26 Aug '12

Hi, I am using stunnel as an encrypted channel between one server and multiple clients. Each client will transfer a very small piece of data every 20 seconds. Therefore I want to compare the tradeoff between maintaining multiple sessions with tearing down and re-establish connection every time. I read the performance table in stunnel doc and got a brief idea, but I hope to evaluate the performance for my specific hardware and software setup to make a better decision. I guess my question is how to measure the Max. concurrent sessions? Should I start multiple stunnel instances on client side? Also, how can I tear down a connection automatically after each time data transfer? Thanks Yuqiong

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Behavior
by Javier 17 Aug '12

17 Aug '12

Hi, I want to report 2 different behaviors, one, related to logs and, the other, to close delay. - About the logs, there is a funny thing. If you reload stunnel.conf the log style and amount of information differs from the starting one. I'm under Windows 2000 and these are the general options in stunnel.conf: debug = debug delay = yes output = stunnel.log fips = no The differences can be seen in the attached text file. First part is how is being seen if you don't reload the conf file. The second, after you reload. I, by myself, prefer the second log style. - About the close delay, I don't know when it started to happen (maybe in the version you removed the multiple instance of stunnel or maybe later), but what happens is that stunnel delays about 1-2 seconds to close. It didn't happen before. It was immediately. And has nothing to do with how many services you have, it delays with one service or ten services or… whatever. My system specs, the same as above. But it happens in Windows XP as well, and with the latest 4.54 beta too (the one that has removed the annoying app error (thank you so much for this :-) )). Have a look to them ;-) and confirm if possible :-) Thanks.

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Stunnel high memory usage?
by Matt Wise 16 Aug '12

16 Aug '12

We use Stunnel 4.5.2 in our environment of Ubuntu 10.04/12.04 systems in various clouds. We're leveraging PGPool for SSL encryption of a lot of different types of traffic ... Zookeeper, Postgresql, and AMQP traffic are some examples for us. Mostly everything works great .. its fast, and very reliable. I've just noticed though that on a particular group of machines we are seeing really high memory usage on the Stunnel process that seems to grow and grow over time. I found this Stunnel process using over 350MB of ram yesterday ... and on an m1.small in Amazon, thats a big chunk! Here's our client config file: > cert = /etc/stunnel/localhost-pgpool.pem > key = /etc/stunnel/localhost-pgpool.key > CAfile = /etc/stunnel/localhost-pgpool_ca.pem > verify = 2 > delay = no > sslVersion = TLSv1 > client = yes > setuid = stunnel4 > setgid = stunnel4 > pid = /var/lib/stunnel4/localhost-pgpool.stunnel4.pid > socket = l:TCP_NODELAY=1 > socket = r:TCP_NODELAY=1 > TIMEOUTconnect = 2 > session = 86400 > debug = 4 > [localhost-pgpool] > accept = 127.0.0.1:5001 > failover = rr > connect = prod-pgpool1-uswest1:6433 > connect = prod-pgpool2-uswest1:6433 My first thought was that perhaps the Session cache was too large... so I dropped it to '3600'. Now instead of 360MB, I'm seeing Stunnel sit at around 170MB. Is the session ID cache just caching thousands and thousands of new session IDs without properly re-using them? It seems like the session ID cache should never have more than: Currently_Used_Session_IDs + Session_IDs_unused_but_last_used_within_the_last_hour Any thoughts on what might be going on? --Matt

1 0

Application Failed to Initialize Properly (0xc0150002)
by Thomas Eifert 09 Aug '12

09 Aug '12

New problem here. Stunnel version 4.53. I just did a fresh install of Windows XP Pro x86 SP3, and did all the Windows updates as well. Whenever I try to launch Stunnel or install the service, I get the error: "Application Failed to Initialize Properly (0xc0150002)" I've never seen this before. I thought it might have something to do with not having the Visual C++ Redistributables, so I installed those too, with the same result. Has anyone else seen this issue? Regards, Thomas -- Attention: This message and all attachments are private and may contain information that is confidential and privileged. If you received this message in error, please notify the sender by reply email and delete the message immediately.

3 4

Stunnel waits for a long time if client does not negotiate SSL
by Denis Solovyov 08 Aug '12

08 Aug '12

Hello, I use stunnel 4.53 to provide pop3s for existing pop3 service. I start stunnel from xinetd, and then exec pop3 utility from stunnel. If a legal pop3s client connects to a server, everything's fine. But if I try to do "telnet host 995" with a simple telnet client and then just do nothing (or even close telnet client without quitting) stunnel process keeps waiting for a very long time (actually maybe forever, I just kill it). The last line in log in such case "Service [stunnel] accepted connection from xx.xx.xx.xx:xxxx". No stunnel TIMEOUT* options have effect in this situation. What can I do to avoid such "waiting"? Maybe stunnel should have something like "SSL negotiation timeout"? Or is there a way to emulate it? (Analyzing `ps` or `netstat` is a bad idea of course.) With the best regards, Denis Solovyov

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Re: [stunnel-users] Application Failed to Initialize Properly (0xc0150002)
by Generic Poster 08 Aug '12

08 Aug '12

Hi Thomas, I have the exact same error when trying to run stunnel on a virtual XP machine under windows 7. I asked here and the only reply I got was that it sounded like a configuration problem. I have tried everything I can think of, but to no avail. I just gave up trying in the end. Wednesday, August 8, 2012, 2:20:43 AM, you wrote: > New problem here. Stunnel version 4.53. > I just did a fresh install of Windows XP Pro x86 SP3, and did all the > Windows updates as well. > Whenever I try to launch Stunnel or install the service, I get the error: > "Application Failed to Initialize Properly (0xc0150002)" > I've never seen this before. I thought it might have something to do > with not having the Visual C++ Redistributables, so I installed those too, > with the same result. > Has anyone else seen this issue? > Regards, > Thomas -- Best regards, GP

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