- stunnel-users - stunnel.org

use of CRYPTO_NUM_LOCKS
by Norm Jacobs 29 Mar '13

29 Mar '13

A while ago, the Solaris security group noticed that stunnel uses CRYPTO_NUM_LOCKS to size a lock table in the code at compile time. They noted that there is function CRYPTO_num_locks() that can do the same thing at runtime and have requested that the function be used so that FIPS/non-FIPS support can be switched on by users simply using interposition. As a result of this, I put together this patch that switches to code to use the function instead of macro. -Norm # stunnel should use CRYPTO_num_locks() function instead of CRYPTO_NUM_LOCKS # macro. The function interogates libcrypto at run-time for sizing and the # macro at compile time. If you interpose a a version at runtime to switch # between FIPS/non-FIPS support, the lock table may not be sized correctly. # diff -r -u stunnel-4.55.orig/src/sthreads.c stunnel-4.55/src/sthreads.c --- stunnel-4.55.orig/src/sthreads.c 2012-08-09 14:44:18.000000000 -0700 +++ stunnel-4.55/src/sthreads.c 2013-03-21 23:29:34.912001586 -0700 @@ -212,7 +212,7 @@ #ifdef USE_PTHREAD static pthread_mutex_t stunnel_cs[CRIT_SECTIONS]; -static pthread_mutex_t lock_cs[CRYPTO_NUM_LOCKS]; +static pthread_mutex_t *lock_cs; void enter_critical_section(SECTION_CODE i) { pthread_mutex_lock(stunnel_cs+i); @@ -275,13 +275,15 @@ int sthreads_init(void) { int i; + int num_locks = CRYPTO_num_locks(); /* initialize stunnel critical sections */ for(i=0; i<CRIT_SECTIONS; i++) pthread_mutex_init(stunnel_cs+i, NULL); /* initialize OpenSSL locking callback */ - for(i=0; i<CRYPTO_NUM_LOCKS; i++) + lock_cs = calloc(num_locks, sizeof (*lock_cs)); + for(i=0; i<num_locks; i++) pthread_mutex_init(lock_cs+i, NULL); CRYPTO_set_id_callback(stunnel_thread_id); CRYPTO_set_locking_callback(locking_callback);

1 0

SSL VPN configuration confusion
by TJ 28 Mar '13

28 Mar '13

I'm using stunnel v4.56 on Linux (Ubuntu) and trying to configure a routed tunnel in conjunction with pppd. I could do with some help to figure it out - my biggest problem is not knowing what a good connection configuration or log looks like. I've read lots of (old) patchy articles on how it is done but the instructions are either hopelessly out of date, or plain wrong. During extensive trial and error I found what appeared to be bugs in the Ubuntu distro-packaged v4.42 but as I don't yet know what a successful connection log looks like they may have been red herrings. The main issue I was trying to build out of was (on the server): SSL accepted: new session negotiated Negotiated ciphers: ECDHE-RSA-RC4-SHA SSLv3 Kx=ECDH Au=RSA Enc=RC4(128) Mac=SHA1 TTY=/dev/pts/4 allocated Local mode child started (PID=17247) Remote FD=1 initialized TCP_NODELAY: Socket operation on non-socket (88) Connection reset: 0 bytes sent to SSL, 0 bytes sent to socket linger (remote): Socket operation on non-socket (88) Service vpn finished (0 left) At this point there would be no pppX interfaces. I created an up-to-date Debian/Ubuntu package for v4.56 which has been more successful. Both ends of the link have the same x86 (i386) package installed. On the server again: stunnel: LOG6[23986:3073268544]: SSL accepted: new session negotiated stunnel: LOG6[23986:3073268544]: Negotiated TLSv1/SSLv3 ciphersuite: ECDHE-RSA-RC4-SHA (128-bit encryption) stunnel: LOG6[23986:3073268544]: Compression: null, expansion: null stunnel: LOG7[23986:3073268544]: TTY=/dev/pts/5 allocated stunnel: LOG6[23986:3073268544]: Local mode child started (PID=23989) stunnel: LOG7[23986:3073268544]: Remote socket (FD=14) initialized stunnel: LOG3[23986:3073268544]: TCP_NODELAY: Socket operation on non-socket (88) stunnel: LOG4[23986:3073268544]: Failed to set remote socket options pppd[23989]: pppd options in effect: pppd[23989]: debug^I^I# (from /etc/ppp/peers/pella-vpn) pppd[23989]: updetach^I^I# (from /etc/ppp/peers/pella-vpn) pppd[23989]: linkname pella^I^I# (from /etc/ppp/peers/pella-vpn) pppd[23989]: ktune^I^I# (from /etc/ppp/peers/pella-vpn) pppd[23989]: unit 3^I^I# (from /etc/ppp/peers/pella-vpn) pppd[23989]: dump^I^I# (from /etc/ppp/peers/pella-vpn) pppd[23989]: nomp^I^I# (from /etc/ppp/peers/pella-vpn) pppd[23989]: noauth^I^I# (from /etc/ppp/peers/pella-vpn) pppd[23989]: ^I^I# (from /etc/ppp/options) pppd[23989]: notty^I^I# (from /etc/ppp/peers/pella-vpn) pppd[23989]: crtscts^I^I# (from /etc/ppp/options) pppd[23989]: local^I^I# (from /etc/ppp/peers/pella-vpn) pppd[23989]: noaccomp^I^I# (from /etc/ppp/peers/pella-vpn) pppd[23989]: asyncmap 0^I^I# (from /etc/ppp/options) pppd[23989]: nopcomp^I^I# (from /etc/ppp/peers/pella-vpn) pppd[23989]: silent^I^I# (from /etc/ppp/peers/pella-vpn) pppd[23989]: lcp-echo-failure 4^I^I# (from /etc/ppp/options) pppd[23989]: lcp-echo-interval 30^I^I# (from /etc/ppp/options) pppd[23989]: hide-password^I^I# (from /etc/ppp/options) pppd[23989]: novj^I^I# (from /etc/ppp/peers/pella-vpn) pppd[23989]: noipdefault^I^I# (from /etc/ppp/peers/pella-vpn) pppd[23989]: noccp^I^I# (from /etc/ppp/peers/pella-vpn) pppd[23989]: noipx^I^I# (from /etc/ppp/options) pppd[23989]: pppd 2.4.5 started by root, uid 0 pppd[23989]: using channel 19 udevd[2122]: device 0xb7b0a6e8 has devpath '/devices/virtual/net/ppp3' udevd[2122]: created empty file '/run/udev/data/n27' for '/devices/virtual/net/ppp3' pppd[23989]: Using interface ppp3 pppd[23989]: Connect: ppp3 <--> /dev/pts/6 Both ends of the link have ppp interfaces but neither have IP addresses. The server configuration is: ----- /etc/stunnel/pella-vpn.conf ----- CAfile = /etc/stunnel/vpn.pem cert = /etc/stunnel/vpn.pem key = /etc/stunnel/vpn.pem output = /var/log/stunnel-vpn.log #verify = 2 debug = 7 client = no foreground = no [vpn] accept = 109.74.x.y:9876 exec = /usr/sbin/pppd execargs = pppd call pella-vpn 10.254.241.1:10.254.241.2 pty = yes ---------- ----- /etc/ppp/peers/pella-vpn ----- unit 3 notty ktune local noipdefault noccp noauth novj nomp nopcomp noaccomp silent updetach linkname pella debug dump ---------- # ifconfig ppp3 ppp3 Link encap:Point-to-Point Protocol POINTOPOINT NOARP MULTICAST MTU:1500 Metric:1 RX packets:0 errors:0 dropped:0 overruns:0 frame:0 TX packets:0 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:3 RX bytes:0 (0.0 B) TX bytes:0 (0.0 B) The client configuration is: ---- /etc/network/interfaces ----- # SSL VPN to Pella iface ppp3 inet ppp unit 3 provider pella-vpn pre-up /sbin/ifconfig ppp0 up ---------- ----- /etc/ppp/peers/pella-vpn ----- # ensure we use ppp3 (ppp0-2 are already in use) unit 3 ktune local noipdefault noccp noauth novj nomp nopcomp noaccomp silent updetach logfd 2 linkname pella pty "/usr/bin/stunnel4 /etc/stunnel/pella.conf.vpn" user "tj" # debugging debug dump ---------- ----- /etc/stunnel/pella.conf.vpn ----- pid = /var/run/stunnel4/pella.pid debug = debug output = /var/log/stunnel-pella.log foreground = no client=yes connect = 109.74.x.y:9876 CAfile = /etc/stunnel/vpn.pem # verify the peer's certificate verify = 2 ---------- # ifup ppp3 pppd options in effect: debug # (from /etc/ppp/peers/pella-vpn) updetach # (from command line) logfd 2 # (from /etc/ppp/peers/pella-vpn) linkname pella # (from /etc/ppp/peers/pella-vpn) ktune # (from /etc/ppp/peers/pella-vpn) unit 3 # (from command line) dump # (from /etc/ppp/peers/pella-vpn) nomp # (from /etc/ppp/peers/pella-vpn) noauth # (from /etc/ppp/peers/pella-vpn) user tj # (from /etc/ppp/peers/pella-vpn) # (from /etc/ppp/options) pty /usr/bin/stunnel4 /etc/stunnel/pella.conf.vpn # (from /etc/ppp/peers/pella-vpn) crtscts # (from /etc/ppp/options) local # (from /etc/ppp/peers/pella-vpn) noaccomp # (from /etc/ppp/peers/pella-vpn) asyncmap 0 # (from /etc/ppp/options) nopcomp # (from /etc/ppp/peers/pella-vpn) silent # (from /etc/ppp/peers/pella-vpn) lcp-echo-failure 4 # (from /etc/ppp/options) lcp-echo-interval 30 # (from /etc/ppp/options) hide-password # (from /etc/ppp/options) novj # (from /etc/ppp/peers/pella-vpn) noipdefault # (from /etc/ppp/peers/pella-vpn) noccp # (from /etc/ppp/peers/pella-vpn) noipx # (from /etc/ppp/options) using channel 43 Using interface ppp3 Connect: ppp3 <--> /dev/pts/5 # ifconfig ppp3 ppp3 Link encap:Point-to-Point Protocol POINTOPOINT NOARP MULTICAST MTU:1500 Metric:1 RX packets:0 errors:0 dropped:0 overruns:0 frame:0 TX packets:0 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:3 RX bytes:0 (0.0 B) TX bytes:0 (0.0 B) # netstat -natp | grep stun tcp 0 0 82.71.a.b:34437 109.74.x.y:9876 ESTABLISHED 24105/stunnel4

1 2

Fw: High memory usage problem.
by mkanet＠yahoo.com 27 Mar '13

27 Mar '13

Jeremy, I know there's an android build of stunnel. Im not trying to be funny, but are you running stunnel on your mobile phone? :) The latest android mobile phones include quadcore CPU's with 2GB's of RAM It would be interesting to see how much of a load a mobile phone can handle with a USB to RJ45 Ethernet interface. Edit: I tried sending this earlier, but it doesn't look like it went through. My apologies in case this is a duplicate. ------------------------ Thanks for taking the time to read this. We're operating on a low spec system that can not be modified at this point. stunnel was introduced at the last minute, without consideration to resource requirements and now consumes enough ram to cause the kernel to issue OOM exceptions. So in short, we are trying to trade increased CPU usage for less memory usage and have tried setting “sessions” to 3600 to reduce memory pressure, but unfortunately it doesn't last. Our current solution is to cron a restart of stunnel on a regular basis, but would prefer to limit number of threads or number of cache entries or something else altogether similarly gentler. Thanks again for your consideration and assistance in this! If there's any specific information I can give, please let me know. Regards, Jeremy

3 7

environment/user variable
by Sebastian Rose-Indorf 26 Mar '13

26 Mar '13

Hello, Stunnel is a very helpful tool. But I miss the support of a environment/user variable to reference the configuration file or the folder of the configuration file: such as %GNUPGHOME% in GnuPG or %OPENSSL_CONF% in OpenSSL. Sebastian

1 0

the range of stunnel functionality
by John A. Wallace 26 Mar '13

26 Mar '13

Where can I find more information about the use and functionality of "tstunnel.exe"? Maybe I am going quite blind, but I looked around unsuccessfully. Thanks. John A. Wallace The pen is mightier than the sword, but only if you get in the first stroke.

3 3

stunnel 4.56 released
by Michal Trojnara 23 Mar '13

23 Mar '13

Dear Users, I have released version 4.56 of stunnel. The ChangeLog entry: Version 4.56, 2013.03.22, urgency: HIGH: * New features - Win32 installer automatically configures firewall exceptions. - Win32 installer configures administrative shortcuts to invoke UAC. - Improved Win32 GUI shutdown time. * Bugfixes - Fixed a regression bug introduced in version 4.55 causing random crashes on several platforms, including Windows 7. - Fixed startup crashes on some Win32 systems. - Fixed incorrect "stunnel -exit" process synchronisation. - Fixed FIPS detection with new versions of the OpenSSL library. - Failure to open the log file at startup is no longer ignored. Home page: https://www.stunnel.org/ Download: https://www.stunnel.org/downloads.html SHA-256 hash for stunnel-4.56.tar.gz: 9cae2cfbe26d87443398ce50d7d5db54e5ea363889d5d2ec8d2778a01c871293 Best regards, Mike

2 2

4.56 FIPS startup issue
by Ian Donaldson 23 Mar '13

23 Mar '13

Hi, I've been using stunnel for years and tried to upgrade to 4.56 today and it fails to start with this error: Clients allowed=125 stunnel 4.56 on i386-pc-solaris2.9 platform Compiled/running with OpenSSL 1.0.1e 11 Feb 2013 Threading:PTHREAD Sockets:POLL,IPv6 SSL:ENGINE,OCSP,FIPS Reading configuration from file /opt/local/etc/stunnel.conf FIPS_mode_set: F06D065: error:0F06D065:common libcrypto routines:FIPS_mode_set:fips mode not supported Line 36: "[pop3s]": Failed to initialize SSL str_stats: 5 block(s), 118 data byte(s), 210 control byte(s) I note some mention of FIPS in today's release. 4.55 started ok though with the same version of openssl (and crashed a few hours later), so we're back to 4.54 again. Ian D

1 1

stunnel craches in windows 7 x64
by Mosy Mosy 15 Mar '13

15 Mar '13

I have been facing with a strange bug in stunnel 4.55 (and also in tstunnel) in Windows 7 x64 and also in Windows Server 2003 R2 x86. I redirect TCP connections from a win7 client to a win2k3 server. Stunnel works fine when accepting connections and transferring data. But suddenly crashes when the client program (in the client side) closes the connection (maybe the several connections simultaneously). It happens on the server side too. Because of this problem I have to load a little program to relaunch stunnel whenever it is crashed. What I mean by 'crash' is that the windows shows the "stunnel stops working" and giving the choices to restart,stop, or debug the program. If you need more details I will be pleased to help you in this case. Thank you :) PS: I just have downloaded "stunnel-4.56b1" and I'm using it right now. I see no sign of crashing and instability until this moment :) it seems the bug is eliminated :)

1 0

4.55 is unstable
by Death Master 14 Mar '13

14 Mar '13

Windows build of 4.55, 2013.03.03 crashes every 20-60sec under load. OS:Win7 x64 (with all updates) This bug affects both stunnel and tstunnel. Please fix it soon ;)

5 6

stunnel: SSL routinesdecryption failed or bad record mac
by Kishore Paul 13 Mar '13

13 Mar '13

Hello Everyone, I updated to the latest version of stunnel and openssl and am still getting a lot of decryption fails. stunnel: SSL routines:SSL3_GET_RECORD:decryption failed or bad record mac and a few times it just segfaults: [937987.314573] stunnel: segfault at 7f6164025000 ip 00007f616d8b5adc sp 00007f616e6a9af0 error 4 in libcrypto.so.1.0.0[7f616d84a000+19f000] stunnel 4.54 on x86_64-unknown-linux-gnu platform Compiled with OpenSSL 1.0.1e 11 Feb 2013 Running with OpenSSL 1.0.1 14 Mar 2012 Is there any way to avoid these errors? I limited my cipher set to just RC4-SHA after seeing that there is an issue even in openssl 1.01e-1 for e_aes_cbc_hmac_sha1.c http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=678353 Appreciate your help. Thanks, Kishore

1 0

Need help to configure STUNNEL using proxy socks v5 to send file to a server
by laurent.uk＠bnpparibas.com 11 Mar '13

11 Mar '13

Hi everyone, I need to connect to proxy socks V5 in order to send file in my server. I configure my stunnel like this : sslVersion = SSLv3 client=yes cert = /opt/freeware/etc/stunnel/ca_nopass.pem pid = /var/adm/stunnel_test.pid socket = l:TCP_NODELAY=1 socket = r:TCP_NODELAY=1 debug = 7 output = /logs/stunnel/stunnel.log ; Don't forget to c_rehash CApath ; CApath is located inside chroot jail CApath = /opt/freeware/etc/stunnel/CA_files/ protocol = connect protocolAuthentication = basic protocolHost = ***:8080 [pesit] accept = 12099 connect = ***:433 But it doesn't works! The log from my stunnel client : 2013.03.11 18:57:30 LOG5[26673178:260]: Service pesit accepted connection from ***:48549 2013.03.11 18:57:30 LOG7[26673178:260]: remote socket: FD=1 allocated (non-blocking mode) 2013.03.11 18:57:30 LOG6[26673178:260]: connect_blocking: connecting ::1:10443 2013.03.11 18:57:30 LOG3[26673178:260]: connect_blocking: connect ::1:10443: Connection refused (79) 2013.03.11 18:57:30 LOG7[26673178:260]: remote socket: FD=1 allocated (non-blocking mode) 2013.03.11 18:57:30 LOG6[26673178:260]: connect_blocking: connecting ****:10443 2013.03.11 18:57:30 LOG5[26673178:260]: connect_blocking: connected ****:10443 2013.03.11 18:57:30 LOG5[26673178:260]: Service pesit connected remote server from ****:48551 2013.03.11 18:57:30 LOG7[26673178:260]: Remote FD=1 initialized 2013.03.11 18:57:30 LOG7[26673178:260]: Option TCP_NODELAY set on remote socket 2013.03.11 18:57:30 LOG6[26673178:260]: Client-mode connect protocol negotiations started 2013.03.11 18:57:30 LOG7[26673178:260]: -> CONNECT ****:1080 HTTP/1.1 2013.03.11 18:57:30 LOG7[26673178:260]: -> Host: ****:1080 2013.03.11 18:57:30 LOG7[26673178:260]: -> 2013.03.11 18:57:30 LOG3[26673178:260]: fdgetline: readsocket: Connection reset by peer (73) 2013.03.11 18:57:30 LOG5[26673178:260]: Connection reset: 0 bytes sent to SSL, 0 bytes sent to socket 2013.03.11 18:57:30 LOG7[26673178:260]: Service pesit finished (0 left) 2013.03.11 18:57:30 LOG7[26673178:260]: str_stats: 0 block(s), 0 data byte(s), 0 control byte(s) 2013.03.11 18:57:32 LOG7[26673178:1]: local socket: FD=0 allocated (non-blocking mode) In my stunnel server, i have the following message : "SSL_accept: 1407609B: error:1407609B:SSL routines:SSL23_GET_CLIENT_HELLO:https proxy request" 2013.03.11 18:57:30 LOG7[27525210:1]: Service pesitip accepted FD=0 from ****:48551 2013.03.11 18:57:30 LOG7[27525210:265]: Service pesitip started 2013.03.11 18:57:30 LOG7[27525210:265]: Option TCP_NODELAY set on local socket 2013.03.11 18:57:30 LOG5[27525210:265]: Service pesitip accepted connection from 159.50.49.69:48551 2013.03.11 18:57:30 LOG3[27525210:265]: SSL_accept: 1407609B: error:1407609B:SSL routines:SSL23_GET_CLIENT_HELLO:https proxy request 2013.03.11 18:57:30 LOG5[27525210:265]: Connection reset: 0 bytes sent to SSL, 0 bytes sent to socket 2013.03.11 18:57:30 LOG7[27525210:265]: Service pesitip finished (0 left) 2013.03.11 18:57:30 LOG7[27525210:265]: str_stats: 0 block(s), 0 data byte(s), 0 control byte(s) 2013.03.11 18:57:32 LOG7[27525210:1]: local socket: FD=0 allocated (non-blocking mode) Can you help me to configure my stunnel please? Thanks. Regards, Laurent UK This message and any attachments (the "message") is intended solely for the intended addressees and is confidential. If you receive this message in error,or are not the intended recipient(s), please delete it and any copies from your systems and immediately notify the sender. Any unauthorized view, use that does not comply with its purpose, dissemination or disclosure, either whole or partial, is prohibited. Since the internet cannot guarantee the integrity of this message which may not be reliable, BNP PARIBAS (and its subsidiaries) shall not be liable for the message if modified, changed or falsified. Do not print this message unless it is necessary,consider the environment. ---------------------------------------------------------------------------------------------------------------------------------- Ce message et toutes les pieces jointes (ci-apres le "message") sont etablis a l'intention exclusive de ses destinataires et sont confidentiels. Si vous recevez ce message par erreur ou s'il ne vous est pas destine, merci de le detruire ainsi que toute copie de votre systeme et d'en avertir immediatement l'expediteur. Toute lecture non autorisee, toute utilisation de ce message qui n'est pas conforme a sa destination, toute diffusion ou toute publication, totale ou partielle, est interdite. L'Internet ne permettant pas d'assurer l'integrite de ce message electronique susceptible d'alteration, BNP Paribas (et ses filiales) decline(nt) toute responsabilite au titre de ce message dans l'hypothese ou il aurait ete modifie, deforme ou falsifie. N'imprimez ce message que si necessaire, pensez a l'environnement.

1 0

Mutual Authentication
by Sameer Rahmani 11 Mar '13

11 Mar '13

Hi guys, I want to have secure tunnel to my server and also i want only specified clients can connect via the tunnel to the server. I was reading about mutual authentication but i can't run stunnel using verify=2 or 3 or 4. I confused. Can you please explain for me what should i do to use 2way ssl connection? how does stunnel use this?

2 1

It doesn't work.
by Raemsh Pungavanam 11 Mar '13

11 Mar '13

Hi , i have following issue with latest version of stunnel and openssl. version ====== stunnel - 4.55 openssl - 1.0.1e stunnel.conf ========== # Sample stunnel configuration file # Copyright by Michal Trojnara 2002 # Comment it out on Win32 #cert = /etc/tr69/stunnel.pem key = /etc/tr69/stunnel.pem # chroot = /usr/local/var/run/stunnel/ # PID is created inside chroot jail pid = /var/run/ssl.pid setuid = root setgid = root # Protocol version (all, SSLv2, SSLv3, TLSv1) sslVersion = TLSv1.2 # Workaround for Eudora bug #options = DONT_INSERT_EMPTY_FRAGMENTS # Authentication stuff verify = 1 # don't forget about c_rehash CApath # it is located inside chroot jail: #CApath = /certs # or simply use CAfile instead: #CAfile = /usr/local/etc/stunnel/certs.pem #CAfile = /etc/tr69/ca.crt # CRL path or file (inside chroot jail): #CRLpath = /crls # or simply use CAfile instead: #CRLfile = /usr/local/etc/stunnel/crls.pem # Some debugging stuff debug = 7 output = /var/log/ssl.log foreground = yes # Use it for client mode client = yes # Service-level configuration [https] CAfile = /flash/Cert.pem accept = 127.0.0.1:8001 connect = acs.qacafe.com:80 #accept = 8080 cat /var/log/ssl.log ============== 2013.03.11 18:29:04 LOG5[5849:0]: stunnel 4.55 on mips-openwrt-linux-uclibc platform 2013.03.11 18:29:04 LOG5[5849:0]: Compiled/running with OpenSSL 1.0.1e 11 Feb 2013 2013.03.11 18:29:04 LOG5[5849:0]: Threading:FORK SSL:+ENGINE+OCSP Auth:none Sockets:POLL+IPv6 2013.03.11 18:29:04 LOG5[5849:0]: Reading configuration from file /etc/tr69/stunnel.conf 2013.03.11 18:29:04 LOG7[5849:0]: Compression not enabled 2013.03.11 18:29:04 LOG7[5849:0]: PRNG seeded successfully 2013.03.11 18:29:04 LOG6[5849:0]: Initializing service [https] 2013.03.11 18:29:04 LOG4[5849:0]: Insecure file permissions on /etc/tr69/stunnel.pem 2013.03.11 18:29:04 LOG7[5849:0]: Loaded verify certificates from /flash/Cert.pem 2013.03.11 18:29:04 LOG7[5849:0]: Loaded /flash/Cert.pem revocation lookup file 2013.03.11 18:29:04 LOG7[5849:0]: SSL options set: 0x00000004 2013.03.11 18:29:04 LOG5[5849:0]: Configuration successful 2013.03.11 18:29:04 LOG7[5849:0]: Service [https] (FD=17) bound to 127.0.0.1:8001 2013.03.11 18:29:04 LOG7[5849:0]: Created pid file /var/run/ssl.pid 2013.03.11 18:29:21 LOG7[5849:0]: Service [https] accepted (FD=4) from 127.0.0.1:36039 2013.03.11 18:29:21 LOG7[5920:0]: Service [https] started 2013.03.11 18:29:21 LOG5[5920:0]: Service [https] accepted connection from 127.0.0.1:36039 2013.03.11 18:29:22 LOG6[5920:0]: connect_blocking: connecting 6.0.0.1:80 2013.03.11 18:29:22 LOG7[5920:0]: connect_blocking: s_poll_wait 6.0.0.1:80: waiting 10 seconds 2013.03.11 18:29:22 LOG5[5920:0]: connect_blocking: connected 6.0.0.1:80 2013.03.11 18:29:22 LOG5[5920:0]: Service [https] connected remote server from 61.200.100.100:35694 2013.03.11 18:29:22 LOG7[5920:0]: Remote socket (FD=17) initialized 2013.03.11 18:29:22 LOG7[5920:0]: SNI: sending servername: acs.qacafe.com 2013.03.11 18:29:22 LOG7[5920:0]: SSL state (connect): before/connect initialization 2013.03.11 18:29:22 LOG7[5920:0]: SSL state (connect): SSLv3 write client hello A 2013.03.11 18:30:15 LOG7[5849:0]: Service [https] accepted (FD=4) from 127.0.0.1:36042 2013.03.11 18:30:15 LOG7[5973:0]: Service [https] started 2013.03.11 18:30:15 LOG5[5973:0]: Service [https] accepted connection from 127.0.0.1:36042 2013.03.11 18:30:15 LOG6[5973:0]: connect_blocking: connecting 6.0.0.1:80 2013.03.11 18:30:15 LOG7[5973:0]: connect_blocking: s_poll_wait 6.0.0.1:80: waiting 10 seconds 2013.03.11 18:30:15 LOG5[5973:0]: connect_blocking: connected 6.0.0.1:80 2013.03.11 18:30:15 LOG5[5973:0]: Service [https] connected remote server from 61.200.100.100:35697 2013.03.11 18:30:15 LOG7[5973:0]: Remote socket (FD=17) initialized 2013.03.11 18:30:15 LOG7[5973:0]: SNI: sending servername: acs.qacafe.com 2013.03.11 18:30:15 LOG7[5973:0]: SSL state (connect): before/connect initialization 2013.03.11 18:30:15 LOG7[5973:0]: SSL state (connect): SSLv3 write client hello A 2013.03.11 18:31:40 LOG7[5849:0]: Service [https] accepted (FD=4) from 127.0.0.1:49029 2013.03.11 18:31:40 LOG7[6023:0]: Service [https] started 2013.03.11 18:31:40 LOG5[6023:0]: Service [https] accepted connection from 127.0.0.1:49029 2013.03.11 18:31:40 LOG6[6023:0]: connect_blocking: connecting 6.0.0.1:80 2013.03.11 18:31:40 LOG7[6023:0]: connect_blocking: s_poll_wait 6.0.0.1:80: waiting 10 seconds 2013.03.11 18:31:40 LOG5[6023:0]: connect_blocking: connected 6.0.0.1:80 2013.03.11 18:31:40 LOG5[6023:0]: Service [https] connected remote server from 61.200.100.100:40051 2013.03.11 18:31:40 LOG7[6023:0]: Remote socket (FD=17) initialized 2013.03.11 18:31:40 LOG7[6023:0]: SNI: sending servername: acs.qacafe.com 2013.03.11 18:31:40 LOG7[6023:0]: SSL state (connect): before/connect initialization 2013.03.11 18:31:40 LOG7[6023:0]: SSL state (connect): SSLv3 write client hello A 2013.03.11 18:33:45 LOG7[5849:0]: Service [https] accepted (FD=4) from 127.0.0.1:49032 2013.03.11 18:33:45 LOG7[6074:0]: Service [https] started 2013.03.11 18:33:45 LOG5[6074:0]: Service [https] accepted connection from 127.0.0.1:49032 2013.03.11 18:33:45 LOG6[6074:0]: connect_blocking: connecting 6.0.0.1:80 2013.03.11 18:33:45 LOG7[6074:0]: connect_blocking: s_poll_wait 6.0.0.1:80: waiting 10 seconds 2013.03.11 18:33:45 LOG5[6074:0]: connect_blocking: connected 6.0.0.1:80 2013.03.11 18:33:45 LOG5[6074:0]: Service [https] connected remote server from 61.200.100.100:40054 2013.03.11 18:33:45 LOG7[6074:0]: Remote socket (FD=17) initialized 2013.03.11 18:33:45 LOG7[6074:0]: SNI: sending servername: acs.qacafe.com 2013.03.11 18:33:45 LOG7[6074:0]: SSL state (connect): before/connect initialization 2013.03.11 18:33:45 LOG7[6074:0]: SSL state (connect): SSLv3 write client hello A 2013.03.11 18:34:22 LOG6[5920:0]: init_ssl: s_poll_wait: TIMEOUTbusy exceeded: sending reset 2013.03.11 18:34:22 LOG5[5920:0]: Connection reset: 0 byte(s) sent to SSL, 0 byte(s) sent to socket 2013.03.11 18:34:22 LOG7[5920:0]: Remote socket (FD=17) closed 2013.03.11 18:34:22 LOG7[5920:0]: Local socket (FD=4) closed 2013.03.11 18:34:22 LOG7[5920:0]: Service [https] finished 2013.03.11 18:34:22 LOG7[5920:0]: str_stats: 19 block(s), 877 data byte(s), 798 control byte(s) 2013.03.11 18:34:22 LOG7[5849:0]: Dispatching signals from the signal pipe 2013.03.11 18:34:22 LOG7[5849:0]: Processing SIGCHLD 2013.03.11 18:34:22 LOG7[5849:0]: Process 5920 finished with code 0 2013.03.11 18:34:22 LOG7[5849:0]: Signal pipe is empty 2013.03.11 18:35:15 LOG6[5973:0]: init_ssl: s_poll_wait: TIMEOUTbusy exceeded: sending reset 2013.03.11 18:35:15 LOG5[5973:0]: Connection reset: 0 byte(s) sent to SSL, 0 byte(s) sent to socket 2013.03.11 18:35:15 LOG7[5973:0]: Remote socket (FD=17) closed 2013.03.11 18:35:15 LOG7[5973:0]: Local socket (FD=4) closed 2013.03.11 18:35:15 LOG7[5973:0]: Service [https] finished 2013.03.11 18:35:15 LOG7[5973:0]: str_stats: 19 block(s), 877 data byte(s), 798 control byte(s) 2013.03.11 18:35:15 LOG7[5849:0]: Dispatching signals from the signal pipe 2013.03.11 18:35:15 LOG7[5849:0]: Processing SIGCHLD 2013.03.11 18:35:15 LOG7[5849:0]: Process 5973 finished with code 0 2013.03.11 18:35:15 LOG7[5849:0]: Signal pipe is empty 2013.03.11 18:36:40 LOG6[6023:0]: init_ssl: s_poll_wait: TIMEOUTbusy exceeded: sending reset 2013.03.11 18:36:40 LOG5[6023:0]: Connection reset: 0 byte(s) sent to SSL, 0 byte(s) sent to socket 2013.03.11 18:36:40 LOG7[6023:0]: Remote socket (FD=17) closed 2013.03.11 18:36:40 LOG7[6023:0]: Local socket (FD=4) closed 2013.03.11 18:36:40 LOG7[6023:0]: Service [https] finished 2013.03.11 18:36:40 LOG7[6023:0]: str_stats: 19 block(s), 877 data byte(s), 798 control byte(s) 2013.03.11 18:36:40 LOG7[5849:0]: Dispatching signals from the signal pipe 2013.03.11 18:36:40 LOG7[5849:0]: Processing SIGCHLD 2013.03.11 18:36:40 LOG7[5849:0]: Process 6023 finished with code 0 2013.03.11 18:36:40 LOG7[5849:0]: Signal pipe is empty 2013.03.11 18:38:45 LOG6[6074:0]: init_ssl: s_poll_wait: TIMEOUTbusy exceeded: sending reset 2013.03.11 18:38:45 LOG5[6074:0]: Connection reset: 0 byte(s) sent to SSL, 0 byte(s) sent to socket 2013.03.11 18:38:45 LOG7[6074:0]: Remote socket (FD=17) closed 2013.03.11 18:38:45 LOG7[6074:0]: Local socket (FD=4) closed 2013.03.11 18:38:45 LOG7[6074:0]: Service [https] finished 2013.03.11 18:38:45 LOG7[6074:0]: str_stats: 19 block(s), 877 data byte(s), 798 control byte(s) 2013.03.11 18:38:45 LOG7[5849:0]: Dispatching signals from the signal pipe 2013.03.11 18:38:45 LOG7[5849:0]: Processing SIGCHLD 2013.03.11 18:38:45 LOG7[5849:0]: Process 6074 finished with code 0 2013.03.11 18:38:45 LOG7[5849:0]: Signal pipe is empty Normally under which circumstances this can happen. please help me totally clue less ... Rgds, Ramesh P

1 0

Stunnel SMP enabled?
by Michael Curran 06 Mar '13

06 Mar '13

I am running an Ubuntu system with Stunnel for 443 connections to an application on the back end. Essentially acting as a load balancer. When I look at the processor stats per processor (this is a 6-cpu system) I see cpu0 with almost 4% usage , compared to the other 5 processors hiting maybe .5% usage across the board. Is stunnel SMP enabled and passes processing amongst all 6 Procs? Or does it bind to one Proc and as long as its active it does all its work on just one PROC. We are having a lot of dropped connections when the overall system CPU hits about 23-25% .. which seems to me that it could be pushing just one CPU hard and the other 5 become basically idle. I am setting up to capture some SAR data to help confirm this effort, but it would if I knew that stunnel was setup for SMP processing.

1 0

Re: [stunnel-users] Stunnel as an "HTTPS to HTTPS" proxy
by Javier 05 Mar '13

05 Mar '13

On Tue, 05 Mar 2013 09:04:41 +0200 "jmwb(a)webmail.co.za" <jmwb(a)webmail.co.za> wrote: > Thank you for your response Javier. > > I now understand how to phrase what I am looking for. What I am looking for is > effectively an SSL Man-in-The-Middle (but please be assured that I am not > looking to build malware). However, I am still not certain from your response > that Stunnel can do this. Can the client-side handle SSL or does it only > support clear-text on the client side? > > jmwb Hi, in the example I gave to you is like this. Hope this can help you to understand how stunnel works in such scenario. 1. Web browser without SSL support. 2. It sends clear text to the IP:port where stunnel client is listening. 3. Stunnel in the client machine send ciphered text to the machine with Stunnel acting as server. 4. Stunnel in the server machine sends clear text to the web server. 5. The web server hasn't SSL support. 6. The communication is reversed to reply to the client side. With a diagram. Browser <> clear text <> stunnel<> ciphered <> stunnel <> clear text <> web server Of course, it is possible to make a MiTM attack between browser and stunnel and stunnel and web server at both sides, but not in between. To accomplish such attack you'll first need to access one of the machines and find such scenario. If both sides support SSL you don't need stunnel (unless one of the sides doesn't support SSL) and, therefore, all communications are ciphered P2P. No clear text. Except keyboard/mouse loggers in the client side. As said, is a secure tunnel, an SSL proxy. As you wish. Regards.

1 0

Re: [stunnel-users] Disable SNI in stunnel win32 version
by Lilienberg, Daniel () 05 Mar '13

05 Mar '13

I want to use my Apache as a secure proxy (where Stunnel adds the SSL layer). With SNI enabled, I must send all hosts I want to connect to which is impossible ? This is for internet proxy usage, so all sites on Internet must be available through the proxy. It worked fine before SNI. From: Brian Wilkins [mailto:[email protected]] Sent: den 5 mars 2013 14:14 To: Lilienberg, Daniel () Subject: Re: [stunnel-users] Disable SNI in stunnel win32 version Does this help? http://langui.sh/2009/11/03/ssl-vhosting-on-the-same-ip-aka-sni/ On Tue, Mar 5, 2013 at 8:10 AM, Lilienberg, Daniel () <daniel.lilienberg(a)volvocars.com<mailto:[email protected]>> wrote: Hi, In my local vmware setup im using Apache with mod_ssl on the server side and Stunnel on client side to make a secure proxy. Im using Chrome as webbrowser to connect locally to the apache which bounces me to internet. In my setup everything worked with the older Stunnel 4.3x, but when you upgraded to a newer Openssl it enabled SNI and now its broken. Can I disable SNI in any way or so I need to recompile stunnel with an older OpenSSL package ? Im running on Win32. _______________________________________________ stunnel-users mailing list stunnel-users(a)stunnel.org<mailto:[email protected]> https://www.stunnel.org/cgi-bin/mailman/listinfo/stunnel-users

1 0

Disable SNI in stunnel win32 version
by Lilienberg, Daniel () 05 Mar '13

05 Mar '13

Hi, In my local vmware setup im using Apache with mod_ssl on the server side and Stunnel on client side to make a secure proxy. Im using Chrome as webbrowser to connect locally to the apache which bounces me to internet. In my setup everything worked with the older Stunnel 4.3x, but when you upgraded to a newer Openssl it enabled SNI and now its broken. Can I disable SNI in any way or so I need to recompile stunnel with an older OpenSSL package ? Im running on Win32.

1 0

Stunnel as an "HTTPS to HTTPS" proxy
by jmwb＠webmail.co.za 04 Mar '13

04 Mar '13

Hi, Please could you tell me if Stunnel supports HTTPS on the client-side i.e. a true SSL proxy with client-side SSL and server-side SSL (or if anyone has developed a version that does)? I have tried searching for this without luck because it is difficult to narrow down the search criteria e.g. Stunnel is already cited as an SSL proxy. jmwb ____________________________________________________________ South Africas premier free email service - www.webmail.co.za For super low premiums, click here. http://www.dialdirect.co.za/landing/oct/1/?vdn=15752

2 1

stunnel 4.55 released (security update)
by Michal Trojnara 03 Mar '13

03 Mar '13

Dear Users, I have released version 4.55 of stunnel. This is a massive bugfix release, including a security bugfix. Update is highly recommended. The ChangeLog entry: Version 4.55, 2013.03.03, urgency: HIGH: * Security bugfix - OpenSSL updated to version 1.0.1e in Win32/Android builds. - Buffer overflow vulnerability fixed in the NTLM authentication of the CONNECT protocol negotiation. See https://www.stunnel.org/CVE-2013-1762.html for details. * New features - SNI wildcard matching in server mode. - Terminal version of stunnel (tstunnel.exe) build for Win32. * Bugfixes - Fixed write half-close handling in the transfer() function (thx to Dustin Lundquist). - Fixed EAGAIN error handling in the transfer() function (thx to Jan Bee). - Restored default signal handlers before execvp() (thx to Michael Weiser). - Fixed memory leaks in protocol negotiation (thx to Arthur Mesh). - Fixed a file descriptor leak during configuration file reload (thx to Arthur Mesh). - Closed SSL sockets were removed from the the transfer() c->fds poll. - Minor fix in handling exotic inetd-mode configurations. - WCE compilation fixes. - IPv6 compilation fix in protocol.c. - Windows installer fixes. Home page: https://www.stunnel.org/ Download: https://www.stunnel.org/downloads.html SHA-256 hash for stunnel-4.55.tar.gz: 5a4acecfabd454415c727435acdfca7dc46aa542998fb278293f494a6d36d37a Best regards, Mike

1 0

Broken pipes and TCP resets on parallel requests over stunnel
by Jan Bee 22 Feb '13

22 Feb '13

Hi, I'm running stunnel (ubuntu 4.42-1, confirmed with 4.54 that has been built from source) against a backend I've only limited control over which was running fine for a long time. At some point in the last few days, the clients stopped being able to make *concurrent* HTTP requests (by different threads) over the stunnel. The client applications using the tunnel enounter a 'Connection refused' error. The issue has been isolated to curl requests (instead of the original client application). Running a tcpdump on both, loopback and uplink, showed that every additional request results in an ACK from the stunnel to both the client and the remote side and a few ms later a RST, ACK is sent in the *same* direction (again from the stunnel to both client and remote end). The stunnel log shows an error about a broken pipe whenever these failures occur: Feb 18 11:09:24 x2 stunnel: LOG7[555:139702117717760]: Socket closed on read Feb 18 11:09:24 x2 stunnel: LOG7[555:139702117717760]: Sending SSL write shutdown Feb 18 11:09:24 x2 stunnel: LOG7[555:139702117717760]: SSL alert (write): warning: close notify Feb 18 11:09:24 x2 stunnel: LOG6[555:139702117717760]: SSL_shutdown successfully sent close_notify Feb 18 11:09:24 x2 stunnel: LOG5[555:139702117717760]: Error detected on socket (read) file descriptor: Broken pipe (32) Feb 18 11:09:24 x2 stunnel: LOG5[555:139702117717760]: Connection reset: 1320 bytes sent to SSL, 48625 bytes sent to socket Feb 18 11:09:24 x2 stunnel: LOG7[555:139702117717760]: Service xtunnel finished (4 left) An strace on the stunnel shows: 6425 <... setsockopt resumed> ) = 0 6425 close(18 <unfinished ...> 6465 poll([{fd=15, events=POLLOUT}, {fd=22, events=POLLIN}], 2, 43200000 <unfinished ...> 6425 <... close resumed> ) = 0 6465 <... poll resumed> ) = 2 ([{fd=15, revents=POLLOUT|POLLERR|POLLHUP}, {fd=22, revents=POLLIN}]) 6425 sendto(13, "<31>Feb 18 11:34:35 stunnel: LOG7[6395:140601236756224]: Service xtunnel finished (4 left)", 99, MSG_NOSIGNAL, NULL, 0 <unf inished ...> 6465 getsockopt(15, SOL_SOCKET, SO_ERROR, [32], [4]) = 0 6425 <... sendto resumed> ) = 99 6465 futex(0x7fe045ec3754, FUTEX_WAIT_PRIVATE, 2, NULL <unfinished ...> 6425 futex(0x7fe045ec3754, FUTEX_WAKE_PRIVATE, 1 <unfinished ...> 6465 <... futex resumed> ) = -1 EAGAIN (Resource temporarily unavailable) 6425 <... futex resumed> ) = 0 6465 sendto(13, "<29>Feb 18 11:34:35 stunnel: LOG5[6395:140601236686592]: Error detected on socket (read) file descriptor: Broken pipe (32)", 122, MSG_NOSIGNAL, NULL, 0 <unfinished ...> 6425 write(2, "2013.02.15 11:34:35 LOG7[6395:140601236756224]: Service xtunnel finished (4 left)\n", 91 <unfinished ...> 6465 <... sendto resumed> ) = 122 6425 <... write resumed> ) = 91 6465 futex(0x7fe045ec3754, FUTEX_WAKE_PRIVATE, 1 <unfinished ...> 6425 sendto(13, "<31>Feb 18 11:34:35 stunnel: LOG7[6395:140601236756224]: str_stats: 0 block(s), 0 byte(s)", 89, MSG_NOSIGNAL, NULL, 0 <unfinished ...> 6465 <... futex resumed> ) = 0 6465 write(2, "2013.02.15 11:34:35 LOG5[6395:140601236686592]: Error detected on socket (read) file descriptor: Broken pipe (32)\n", 114 <unfinished ...> $ ps auxww|grep stunnel4 shows: root 28587 0.1 0.0 437844 7780 ? Ss 09:37 0:11 /usr/bin/stunnel4 /etc/xtunnel/stunnel.conf root 29170 0.0 0.0 43876 1180 ? S 09:37 0:00 /usr/bin/stunnel4 /etc/xtunnel/stunnel.conf root 29171 0.0 0.0 43876 1180 ? S 09:37 0:00 /usr/bin/stunnel4 /etc/xtunnel/stunnel.conf root 29172 0.0 0.0 43876 1180 ? S 09:37 0:00 /usr/bin/stunnel4 /etc/xtunnel/stunnel.conf root 29173 0.0 0.0 43876 1180 ? S 09:37 0:00 /usr/bin/stunnel4 /etc/xtunnel/stunnel.conf root 29174 0.0 0.0 43876 1180 ? S 09:37 0:00 /usr/bin/stunnel4 /etc/xtunnel/stunnel.conf The stunnel config looks like this: foreground=yes debug=7 pid=/var/run/xtunnel.pid client=yes CAfile=/etc/ssl/certs/xtunnel-chains.pem verify=3 engine=dynamic engineCtrl=SO_PATH:/usr/lib/engines/engine_pkcs11.so engineCtrl=ID:pkcs11 engineCtrl=LIST_ADD:1 engineCtrl=LOAD engineCtrl=MODULE_PATH:libopencryptoki.so.0 engineCtrl=INIT engineCtrl=PIN:XXXXXX [xtunnel] engineNum=1 key=id_4 cert=/etc/xtunnel/client-cert.pem accept=127.0.0.1:9999 connect=192.168.200.1:8443 Does anyone have an idea what could be going wrong here or how to troubleshoot this any further? Thanks! Jan

1 0

Stunnel in pgsql mode, libpq, and SSL session caching..
by Matt Wise 17 Feb '13

17 Feb '13

Is there any level of SSL Session Caching when using Stunnel in pgsql mode, and using libpq-based Postgres clients? If not, I'm wondering what tuning we can do on the Stunnel side to get the best performance if we have alot of clients that connect very fequently to the servers.. --matt

1 0

STUNNEL --- How to chose the AES cipher with TLS v1.2
by Editor 14 Feb '13

14 Feb '13

Hi to all: In reading the FAQ and looking at the sample configuration file, I do not see an example of how to correctly configure the application to use the more current AES-256 or the AES-128 cipher configurations. I do have the current OpenSSL on the host (a Sun SPARC box). The idea is to use this host as a SSL proxy for a number of services. I did see this reference: options = CIPHER_SERVER_PREFERENCE But not how to then set the SSL cipher except as I found on Google. There was this on the MAN page but it seems to fail in my configuration: ciphers = cipherlist Select permitted SSL ciphers. A colon delimited list of the ciphers to allow in the SSL connection. For example DES-CBC3-SHA:IDEA-CBC-MD5 Thanks. Kevin Reference Ciphers supported by OpenSSL: http://www.openssl.org/docs/apps/ciphers.html

2 1

stunnel port question
by Stewart Anderson 13 Feb '13

13 Feb '13

Hi all, ty in advance for any help. I have a service that I can connect to a destination over stunnel, but I am not able to get the ack I expect. Internal sending service => stunnel => external listening service I think the problem may be that the firewall is blocking inbound traffic. I need to specify a specific port for the firewall team to open so that traffic can get back to my stunnel service, since every time stunnel starts it will be making a connection from a different port on the external facing side of the SSL encapsulation service/pipe/whatever you want to call it!! What would be the best way to configure stunnel for that scenario. I can see the INETD mode but that does not seem to be what I am looking for, I can also see the transparent option but not sure what that really does. Any advice appreciated. Regards Stewart Your Hospital needs YOU! We need you to register as a Public, Patient or Staff member and help shape the future of your healthcare. Call 0800 280 2581 to register by phone or you can email bradfordhospitals(a)capitaregistrars.com<mailto:[email protected]> and ask to be registered as a new member. For more information about our hospitals and Foundation Trust Membership please visit www.bradfordhospitals.nhs.uk<http://www.bradfordhospitals.nhs.uk> This message is confidential. It may also contain privileged information. The contents of this e-mail and any attachments are intended for the named addressee only. Unless you are the named addressee or authorised to receive the e-mail of the named addressee you may not disclose, use or copy the contents of the e-mail. If you are not the person for whom the message was intended, please notify the sender immediately at Bradford Teaching Hospitals NHS Foundation Trust and delete the material from your computer. You must not use the message for any other purpose, nor disclose its contents to any person other than the intended recipient. Bradford Teaching Hospitals NHS Foundation Trust does not accept responsibility for this message and any views or opinions contained in this e-mail are solely those of the author unless expressly stated otherwise.

1 0

Stunnel over a separate proxy?
by Alex Gottschalk 12 Feb '13

12 Feb '13

I've successfully deployed stunnel4 to wrap rsync for transferring data between remote sites and a central repository. The issue I'm running into, is that some of these sites mandate use of a proxy (HTTP or SOCKS5 usually) for outbound network connections. It seems like there is some proxy support in stunnel with the protocol{Host,Authentication,etc} configuration options, but I have had zero luck getting them to work. For example, I've tried making a simple SOCKS5 proxy using ssh, that I'm successfully able to send HTTP traffic over: ssh -g -D1080 proxy-host # create the proxy, open port 1080 on a public interface then in the client stunnel.conf: [rsync] protocol = connect protocolHost = proxy-host:1080 accept = 127.0.0.1:873 connect = rsync-destination:443 Keep in mind this is an already-working stunnel - the only difference is the addition of the protocol and protocolHost lines above. When I run stunnel in the foreground with that configuration change, I get the following error trying to run rsync: $ rsync -v dev.inst.kvpdata rsync://localhost/putdata/ rsync: read error: Connection reset by peer (104) rsync error: error in rsync protocol data stream (code 12) at io.c(605) [sender=2.6.9] And no log messages appear in stunnel's stderr whatsoever. What am I doing wrong? I get identical results using an HTTP proxy with squid, instead of the socks5 proxy. Thanks, please let me know if there's any more information I should include to help with figuring this out. Alex Gottschalk

3 4

transfer() loop executes not transferring any data and truncated data when using unix sockets
by Stephen Balukoff 08 Feb '13

08 Feb '13

Hello! Recently we started seeing some erroneous behavior in one of our load balancer configurations in which we're using stunnel for SSL tunnel termination with web clients. Specifically, the setup looks like the following: Web client ---(SSL)---> stunnel ---(unix socket)--> haproxy ---(tcp/http)---> web server After extensive troubleshooting we were able to determine that when the following parameters are present: * Client forces non-keepalive connection * Client generates a POST request, the response to which (generated by the back-end web server) is greater than about 8k * stunnel and haproxy communicate via unix socket ...then most responses end up being truncated by an extraneous TCP RST packet from stunnel, and the following log lines are generated: Jan 23 15:24:17 ds420a stunnel: LOG3[22586:139835614443264]: transfer() loop executes not transferring any data Jan 23 15:24:17 ds420a stunnel: LOG3[22586:139835614443264]: please report the problem to Michal.Trojnara(a)mirt.net Jan 23 15:24:17 ds420a stunnel: LOG3[22586:139835614443264]: stunnel 4.54 on x86_64-unknown-linux-gnu platform Jan 23 15:24:17 ds420a stunnel: LOG3[22586:139835614443264]: Compiled/running with OpenSSL 1.0.0-fips 29 Mar 2010 Jan 23 15:24:17 ds420a stunnel: LOG3[22586:139835614443264]: Threading:PTHREAD SSL:+ENGINE+OCSP+FIPS Auth:none Sockets:POLL+IPv6 Jan 23 15:24:17 ds420a stunnel: LOG3[22586:139835614443264]: protocol=TLSv1, SSL_pending=0 Jan 23 15:24:17 ds420a stunnel: LOG3[22586:139835614443264]: sock_open_rd=n, sock_open_wr=Y Jan 23 15:24:17 ds420a stunnel: LOG3[22586:139835614443264]: SSL_RECEIVED_SHUTDOWN=n, SSL_SENT_SHUTDOWN=Y Jan 23 15:24:17 ds420a stunnel: LOG3[22586:139835614443264]: sock_can_rd=Y, sock_can_wr=n Jan 23 15:24:17 ds420a stunnel: LOG3[22586:139835614443264]: ssl_can_rd=n, ssl_can_wr=n Jan 23 15:24:17 ds420a stunnel: LOG3[22586:139835614443264]: read_wants_read=Y, read_wants_write=n Jan 23 15:24:17 ds420a stunnel: LOG3[22586:139835614443264]: write_wants_read=n, write_wants_write=n Jan 23 15:24:17 ds420a stunnel: LOG3[22586:139835614443264]: shutdown_wants_read=n, shutdown_wants_write=n Jan 23 15:24:17 ds420a stunnel: LOG3[22586:139835614443264]: socket input buffer: 0 byte(s), ssl input buffer: 0 byte(s) The work arounds we have found are either: 1. Make stunnel and haproxy communicate over a TCP socket bound to the loopback interface (less ideal, as then we're limited to 65k connections) 2. Add the "reset=no" parameter to our stunnel.conf (which seems to fix the problem, but makes me wonder if we're not opening ourselves up to other problems-- like really getting stuck in an infinite loop that that watchdog is intended to avoid.) In any case based on what "reset=no" is supposed to do as well as where that first line of the error output above is being generated in the code, it's clear that the main client data transfer loop in client.c (starting line 519) is being called too often with no data to transfer, which triggers the infinite loop detection in the transfer() function (client.c, starting line 832). My best hypothesis at this point is that the transfer() code was written only with TCP sockets in mind, and that something about the unix socket in use here is triggering that loop too often. Maybe s_poll_wait on line 541 is being called with parameters which are right for a TCP socket but inappropriate for a unix socket? At this point though, we're at the limit of my socket programming ability, so I'm a little stuck. (Would like to have simply fixed this and submitted a patch... but cest la vie, eh.) We'd like to avoid using a TCP socket to communicate between stunnel and haproxy simply because it's a little less efficient, and because there's an artificial 65k limit on the number of back-end connections we can support per loopback IP if we do that. Alternatively, if someone could verify that "reset=no" is an acceptable / safe work around in this case, I'd appreciate that (though, of course, I'd prefer my logs not to get spammed on every connection. :P ) Is there any other data I can provide to help troubleshoot and fix this? Thanks, Stephen -- Stephen Balukoff Blue Box Group, LLC (800)613-4305 x807

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