January 2006 - stunnel-users

stunnel and syslog
by Bart Somers 10 Feb '06

10 Feb '06

Hi to all, We recently ran in to a problem using stunnel on our AIX 5.2 machines. This is our situation: we are running stunnel as a client to protect http (and a proprietary protocol) traffic between our company and a customer. We are using client-athentication to grant access to the server and on our client-side we validate the server-certificates. This all works fine. Due to new security-restrictions, we are moving all our private-key material into HSM-boxes, in our case these are nCipher nShield HSM's. According to the documantion on there website ( http://active.ncipher.com ) we builded openssl nCipher-enabled. Based on this openssl-version, we builded stunnel. All the build-options are shown below in this message. The compiler used is the IBM C compiler. According to the manuals from stunnel we needed to put in an extra line to the config-file which shows "engine = chil" (chil is the Cryptographic Hardware Interface Library, the way the nCipher HSM's are known to openssl) After all this, we created key's in the hsm, using the nCipher tools and loaded them into stunnel (using this method you get a "pseudo-pem-file", which is actually a reference to the hardware-key). Fire-up stunnel using the commands from nCipher to preload the key's and we are all good to go! When this all seems to work very stable after a few months, with thousands of connections and ditto megabytes transfered, we wanted to have all the logging to our syslogserver (it runs syslog-ng) and this is the place where my problem hits in: When commenting-out the option "output = /home/bart/stl/var/stunnel.log" and restarting stunnel, stunnel dies after the first or second connection, leaving no logging, corefiles or whatever behind. Using plain key's (so no HSM, but with the same build which is aware of the HSM), syslog is no problem. Using HSM-key's with plaintext logfiles (no syslog) works also excellent. As i don't have any ideas anymore where to search, i want to ask you if somebody ever have seen this behaviour or knows where it could be caused by. (And maybe how to solve it....) Thanks in advance! Best regards, Bart Somers. ############################# # Build- and config-options # ############################# bart@server1:./stunnel -version stunnel 4.11 on powerpc-ibm-aix5.2.0.0 UCONTEXT+POLL+IPv4 with OpenSSL 0.9.8 05 Jul 2005 Global options cert = home/bart/stl/etc/stunnel/stunnel.pem ciphers = ALL:!ADH:+RC4:@STRENGTH debug = 5 key = /home/bart/stl/etc/stunnel/stunnel.pem pid = /home/bart/stl/var/run/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 bart@server1:./openssl version OpenSSL 0.9.8 05 Jul 2005 compile-options: Openssl: $ export LDFLAGS="-L/opt/nfast/toolkits/hwcrhk" $ ./config --prefix=/home/bart/stl –DNFast –ldl make and make install Stunnel: $ export CPPFLAGS="-I/home/bart/stl/include" $ export LDFLAGS="-L/opt/nfast/toolkits/hwcrhk" $ ./configure –-prefix=/home/bart/stl –-with-ssl=/home/bart/stl -–disable-libwrap make and make install Config-file: Include engine = chil Start-up: $ with-nfast –f /home/bart/stl/tmp/ff /home/bart/stl/sbin/stunnel /home/bart/stl/etc/stunnel/stunnel.conf Relevant information from the config-file: engine = chil cert = /home/bart/stl/etc/stunnel/my-key.pem key = /home/bart/stl/etc/stunnel/my-key-hsm.pem ;(no chroot options used) pid = /prj/stl_004/tmp/test/stunnel-client.pid debug = 7 ; output = /home/bart/stl/var/stunnel.log # when in comment, problems! client = yes [test] accept = 9400 connect = 10.10.10.10:443 All other values are the default from the example.

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FQDN validation and checking within
by Nagasundaram, Sekhar 31 Jan '06

31 Jan '06

Mike: Given this: what is the best way for Stunnel to make authentication And authorization decisions based on information presented in the Certificate from the peer. My question comes from: how do I do level 3 Checking in a scalable manner when my order of magnitude is in the Thousands... Much thanks Sekhar ------------------------------- Message: 3 Date: Tue, 31 Jan 2006 09:51:06 +0100 From: "Michal Trojnara" <Michal.Trojnara(a)mobi-com.net> Subject: RE: [stunnel-users] FQDN validation and checking within STunnel To: <stunnel-users(a)mirt.net> Message-ID: <20060131085108.B053F1C130(a)linode.mirt.net> Content-Type: text/plain; charset="us-ascii" Nagasundaram, Sekhar wrote: > Is there a setting in Stunnel to do FQDN checking? DNS is not a secure protocol (http://www.securesphere.net/download/papers/dnsspoof.htm) Security should not be based on DNS checks. I'm not going to implement this feature. Best regards, Mike ------------------------------ Message: 4 Date: Tue, 31 Jan 2006 10:41:37 +0100 From: "Michal Trojnara" <Michal.Trojnara(a)mobi-com.net> Subject: RE: --with-threads=ucontext portability (was Re: [stunnel-users] stunnel4.x.x and IRIX) To: <stunnel-users(a)mirt.net> Message-ID: <20060131094139.33A011C17C(a)linode.mirt.net> Content-Type: text/plain; charset="iso-8859-1" Miloslav Trmac wrote: > I have just seen a crash at a similar place on x86_64. The apparent > cause is sthreads.c:116: > makecontext(&ctx->ctx, (void(*)(void))cli, 1, arg); arg is a void > *, but: > - the size is given as 1; it should be > (sizeof (arg) + sizeof (int) - 1) / sizeof (int) > because the "size" is defined as a number of int arguments > - it won't work anyway; makecontext () is defined to work only for > integer parameters. It is not possible to pass a pointer as > integers on x86_64, which uses registers to pass the first 6 > integer or pointer parameters. Are we still talking about IRIX? http://nixdoc.net/man-pages/IRIX/man3c/makecontext.3c.html I can't find any of mentioned limitations in the manual. Just the opposite: "the arguments that follow the argc parameter for makecontext are restricted to longs and pointers only". Best regards, Mike ------------------------------ _______________________________________________ stunnel-users mailing list stunnel-users(a)mirt.net http://stunnel.mirt.net/mailman/listinfo/stunnel-users End of stunnel-users Digest, Vol 18, Issue 19 *********************************************

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Stunnel Question /Feature request
by Mathias . 31 Jan '06

31 Jan '06

Hi everybody. Is it possible at the Client side specify where the Stunnel server should connect to? I mean. If I'm using stunnel both on the clisnt side and the Server side is it possible from within the Stunnel.conf file specify a destination at serverside that overides the "connect=" tag specified in the stunnel.conf file at the server side. This would make it possible to have two services accessible at the same port. I.e IIS using https (accessible from any browser) and a nother SSL, non-web, based service (accessible from a Stunnel client). Anyone that ever have thought about creating such a patch? /M

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stunnel 4.x.x and IRIX
by Eric Haddix 31 Jan '06

31 Jan '06

I happened upon a user here that posted a couple of months ago(I think) who used IRIX and had successfully compiled stunnel. Any chance you're still around!?!? I get one of two things. Before I apply the patch, it will crash right after startup. No logs, just dumps core. After the patch, it starts and exits immediately. I can run it with -version, etc. and it seems to work fine. Anyone had this and/or know what can be done? Eric

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FQDN validation and checking within STunnel
by Nagasundaram, Sekhar 30 Jan '06

30 Jan '06

All: Is there a setting in Stunnel to do FQDN checking? Level 3 checking requires a local copy of the Peer's certificate. When doing mutual authentication, I run into scalability issues when the devices Run into the thousands using Level3 validation. However, if Stunel was capable of doing FQDN checks, That would help while not requiring me to do level 3 checks (although that is probably better). Thanks Sekhar

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stunnel errors on Solaris
by Kevin Mooney 26 Jan '06

26 Jan '06

Hello All, I am having some errors on a Solaris 8 machine with stunnel. Everything seems to be working fine, but I am just a little leary since it is under security violations. I couldn't get anything from google using the string Too many retries on SSL shutdown. I was curious if anyone has seen this before or if somebody might have an idea as to what this means. Thank You, Kevin Security Violations =-=-=-=-=-=-=-=-=-= Jan 26 14:38:24 duvel stunnel: [ID 821868 daemon.notice] LOG5[23863:11151]: Too many retries on SSL shutdown Jan 26 14:38:24 duvel stunnel: [ID 821868 daemon.notice] LOG5[23863:11151]: Too many retries on SSL shutdown Jan 26 15:28:19 duvel stunnel: [ID 821868 daemon.notice] LOG5[23863:11180]: Too many retries on SSL shutdown Jan 26 15:28:19 duvel stunnel: [ID 821868 daemon.notice] LOG5[23863:11180]: Too many retries on SSL shutdown Jan 26 14:38:24 duvel stunnel: [ID 821868 daemon.notice] LOG5[23863:11151]: Too many retries on SSL shutdown Jan 26 15:28:19 duvel stunnel: [ID 821868 daemon.notice] LOG5[23863:11180]: Too many retries on SSL shutdown

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Stunnel and Forte Agent
by Malcolm William Mason 26 Jan '06

26 Jan '06

Hello to all, I have been using Stunnel to access News Groups at ATT.net to by-pass or tunnel through ATT's SSL for some time. I have run into trouble and I am getting a message "connection" failed. At first I thought that it was Stunnel and after deleting and re-installing Stunnel, I an getting the same RESULT. Was there an older version of Stunnel that worked and will the new, updated Stunnel not work or does it need to have some settings changed? Malcolm Mason MWM1(a)jhu.edu

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Proxy Support and 4.15b2
by Ben Green 25 Jan '06

25 Jan '06

Greetings everyone, I have been working for a few days with Stunnel and have been trying to get it working with the proxy servers that filter all outbound traffic at work. I stumbled across 4.15b2 today and was able to get it all to work well to SSL enable telnet and fix through the connect protocol. I plan to use this in production if all goes well in dev, test, and qa over the next 2 months. I was not around on the list when the announcement went out for 4.15b2 on November 16th (found it in the archives). I'll get to my point, now. I am wondering how testing is going with 4.15b2. Is it going to be released as 4.15, soon? Has anyone put 4.15b2 in a production situation? Thanks. Ben Green

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Win32 proxy enabled version
by Richard Houston 24 Jan '06

24 Jan '06

Hi all, I am looking for a windows version of stunnel with proxy server support. I need to use this from behind a Novel Boarder manager firewall. Also is there any documentation on the config file options? Thanks much in advance! +------------------------------------+ Best regards, -Richard Houston -R.L.H. Consulting -E-Mail rhouston(a)rlhc.net -WWW http://www.rlhc.net -Blog http://www.rlhc.net/blog/

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Re: [stunnel-users] exclusively TLS
by Jesse Small 24 Jan '06

24 Jan '06

I've been working through the same problem as John, but I tried using Jan's solution by setting the options and still haven't been able to get it to work. On server1 I am running openssl s_server with tls-only specified: openssl s_server -accept 8443 -cert XDS_REG_HXTI.cer -key hxti1.key -tls1 On the client side (server2), I have stunnel set up as a client listening on localhost port 8100, and forwarding over to server1, port 8443. Then to test I run 'telnet localhost 8100' and see the error message from s_server: ACCEPT ERROR 16656:error:1408A10B:SSL routines:SSL3_GET_CLIENT_HELLO:wrong version number:s3_srvr.c:683: shutting down SSL CONNECTION CLOSED In my stunnel.log file I can see this error message: SSL_connect: 14094410: error:14094410:SSL routines:SSL3_READ_BYTES:sslv3 alert handshake failure So to me it still seems to be sending out a client hello in sslv3, despite my efforts to the contrary. Below are the pertinent parts of my stunnel_client.conf file. Any help you could give would be greatly appreciated. Thanks, Jesse ; Workaround for Eudora bug ;options = DONT_INSERT_EMPTY_FRAGMENTS options = NO_SSLv2 options = NO_SSLv3 [toOtherServer] accept = 8100 connect = devapp:8443 -----Original Message----- From: Jan Meijer [mailto:jan.meijer@surfnet.nl] Sent: Friday, January 20, 2006 5:20 PM To: Moehrke, John (GE Healthcare) Cc: stunnel-users(a)mirt.net Subject: RE: [stunnel-users] exclusively TLS On Fri, 20 Jan 2006, Moehrke, John (GE Healthcare) wrote: > It is not the list of ciphers that I want to choose from. We are indeed > using a select set of ciphers and that seems to be working fine. My > problem is that when stunnel connects to the server it is trying sslv3, > and this causes an error as the server is only supporting TLS. I could > easily be wrong... Ah, that way. options = SSL_options OpenSSL library options The parameter is the OpenSSL option name as described in the SSL_CTX_set_options(3ssl) manual, but without SSL_OP_ prefix. Several options can be used to specify multiple options. For example for compatibility with erroneous Eudora SSL implementation the following option can be used: options = DONT_INSERT_EMPTY_FRAGMENTS Check the SSL_CTX_set_options manpage, it says -amongst other things-: SSL_OP_NO_SSLv2 Do not use the SSLv2 protocol. SSL_OP_NO_SSLv3 Do not use the SSLv3 protocol. SSL_OP_NO_TLSv1 Do not use the TLSv1 protocol. That ought to do the trick I'd say. Let us know if it did :) Jan -- http://www.surfnet.nl/organisatie/jame

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