November 2019 - stunnel-users

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?

4 3

Re: [stunnel-users] CPU 100%
by Eric Eberhard 05 Nov '24

05 Nov '24

Long ago I had a server with a bad network card. Every once in a while it would spew uncontrollable bytes onto the network. If you open a stunnel connection and it does that this could very well be the problem. If it cheap, try changing the network card. If not, you should be able to look in your firewall/router and it will tell you who is sending what bytes to whomever. See if that machine is indeed streaming the bytes in massive quantities. If not, I would suspect your stunnel is getting stuck in it's own loop. There are a million reasons this can happen (well a few less than a million) - such as maybe a bad library in the FreeBSD or a bad choice in the Makefile - such as doing threads or something in a way your O/S does not like (I use threads=fork or whatever it is, instead of actual threading). You might tinker with some of the options that make the stunnel build and try different ones. Especially if stunnel was compiled on a different version of the O/S - could be differences in bytes in things and who knows what. That is all I can suggest beyond setting the debug level to 7 (I think is highest) and then watching the log file. Eric From: stunnel-users [mailto:[email protected]] On Behalf Of Murrey, Brian J. Sent: Wednesday, October 17, 2018 10:57 AM To: stunnel-users(a)stunnel.org Subject: [stunnel-users] CPU 100% We are running stunnel 5.49 on FreeBSD 11.2 and we're running into a problem once in a while. CPU pegs at 100% when we get an stunnel connection from one of our external devices. This affects 100% of all cores and we can't even log in to console. To mitigate this temporarily, we have a script running in the background to watch when stunnel begins to spike and restarts the daemon. It doesn't happen 100% of the time, and so far I have been unable to distinguish what makes the connection do this to the CPU. Have any of you run in to this issue? Sincerely, Brian Murrey System Engineer II, IT Infrastructure _____ NOTICE: This message may contain privileged and confidential information and/or protected health information intended solely for the use of the named recipient and may be privileged or otherwise protected by law. If you are not the intended recipient of this message, you should immediately notify the sender and delete this message. Do not disseminate, reproduce, or review this message or attachments if you are not the intended recipient. The sender or others may have legal rights restricting the dissemination of the information contained in this message and, as a result, remedies against you in the event of the improper dissemination of confidential information, trade secrets, personal information or privileged communications. This message is the work of the sender and does not necessarily reflect the position, views, or policies of TriMedx LLC or its affiliates. WARNING: The integrity and security of this message cannot be guaranteed and may contain or transmit a virus or other illicit code. Neither TriMedx LLC or its affiliates accept liability for any damage attributable to viruses or illicit code transmitted through this message or an attachment.

2 1

older browsers, stunnel and privoxy
by kovacs janos 04 Mar '24

04 Mar '24

sorry to bother, im trying to make older browsers be able to display TLS 1.1 and TLS 1.2 sites. i heard stunnel cant be configured to always forward to the current site address dynamically, thats why i would use privoxy. the browser is configured to send to: 127.0.0.1 443 stunnel config has this at the end: [Tunnel_in] client = yes accept = 127.0.0.1:443 connect = 127.0.0.1:8118 verifyChain = yes CAfile = ca-certs.pem checkHost = localhost 127.0.0.1:8118 is the privoxy address. this is what stunnel writes: LOG5[main]: Configuration successful LOG5[0]: Service [Tunnel_in] accepted connection from 127.0.0.1:3261 LOG5[0]: s_connect: connected 127.0.0.1:8118 LOG5[0]: Service [Tunnel_in] connected remote server from 127.0.0.1:3262 and the browser infinitely loads, and never loads anything or leaves the page. if i remove the last 3 lines, its the same just with this line added: LOG4[main]: Service [Tunnel_in] needs authentication to prevent MITM attacks but it doesnt give an error or anything. with a configuration like: [Tunnel_out] client = no accept = 127.0.0.1:443 connect = 127.0.0.1:8118 cert = stunnel.pem this is what it gives: LOG5[3]: Service [Tunnel_out] accepted connection from 127.0.0.1:3294 LOG3[3]: SSL_accept: 1407609B: error:1407609B:SSL routines:SSL23_GET_CLIENT_HELLO:https proxy request LOG5[3]: Connection reset: 0 byte(s) sent to TLS, 0 byte(s) sent to socket and browser gives a server not found error immediately. im not even sure if i should use client or server configuration in a case like this, but none of them works anyway. all i would need is for my browser to get the pages decrypted, or at least in less than TLS1.1. like how on newipnow.com i can access sites with any encryption, since they are sent to the browser without encryption. the browser just gives an "unencrypted tunnel" warning, which is how i found stunnel, and which is exactly what i need, just locally.

8 41

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 & 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

2 1

SMTP out via Comcast stopped working
by Carlos Rodriguez 30 Nov '19

30 Nov '19

All: I have had this setup working fine since Comcast blocked port 25 and recently stopped working. This is a MS Small Business Server 2003 with Exchange, I know, old and obsolete but I would like to keep it working until I migrate to Linux. Anyway, right now I also have my desktop, Win10, using the same SMTP settings for the Acronis backup event results and it can send me emails just fine, just tested this. So it is not my firewall or Comcast. I'm missing something in the settings of stunnel. Below are my settings and log file. Any suggestions will be appreciated. Carlos taskbar = yes [SSLsmtp] client = yes accept = localhost:555 connect = smtp.comcast.net:587 protocol = smtp CAfile = ca-certs.pem protocolUsername = verifiedusername protocolPassword = verifiedpassword debug = 7 ================================================ 2019.11.29 16:31:24 LOG5[main]: stunnel 5.49 on x86-pc-msvc-1500 platform 2019.11.29 16:31:24 LOG5[main]: Compiled/running with OpenSSL 1.0.2p-fips 14 Aug 2018 2019.11.29 16:31:24 LOG5[main]: Threading:WIN32 Sockets:SELECT,IPv6 TLS:ENGINE,FIPS,OCSP,PSK,SNI 2019.11.29 16:31:24 LOG5[main]: Reading configuration from file stunnel.conf 2019.11.29 16:31:24 LOG5[main]: UTF-8 byte order mark detected 2019.11.29 16:31:24 LOG5[main]: FIPS mode disabled 2019.11.29 16:31:26 LOG4[main]: Service [SSLsmtp] needs authentication to prevent MITM attacks 2019.11.29 16:31:26 LOG5[main]: Configuration successful 2019.11.29 16:34:12 LOG7[0]: Service [SSLsmtp] started 2019.11.29 16:34:12 LOG7[0]: Setting local socket options (FD=264) 2019.11.29 16:34:12 LOG7[0]: Option TCP_NODELAY set on local socket 2019.11.29 16:34:12 LOG5[0]: Service [SSLsmtp] accepted connection from 127.0.0.1:1268 2019.11.29 16:34:12 LOG6[0]: s_connect: connecting 96.114.157.81:587 2019.11.29 16:34:12 LOG7[0]: s_connect: s_poll_wait 96.114.157.81:587: waiting 10 seconds 2019.11.29 16:34:12 LOG5[0]: s_connect: connected 96.114.157.81:587 2019.11.29 16:34:12 LOG5[0]: Service [SSLsmtp] connected remote server from 10.10.10.99:1269 2019.11.29 16:34:12 LOG7[0]: Setting remote socket options (FD=288) 2019.11.29 16:34:12 LOG7[0]: Option TCP_NODELAY set on remote socket 2019.11.29 16:34:12 LOG7[0]: Remote descriptor (FD=288) initialized 2019.11.29 16:34:12 LOG7[0]: <- 220 resomta-po-02v.sys.comcast.net resomta-po-02v.sys.comcast.net ESMTP server ready 2019.11.29 16:34:12 LOG7[0]: -> 220 resomta-po-02v.sys.comcast.net resomta-po-02v.sys.comcast.net ESMTP server ready 2019.11.29 16:34:12 LOG7[0]: -> EHLO localhost 2019.11.29 16:34:12 LOG7[0]: <- 250-resomta-po-02v.sys.comcast.net hello [71.206.38.109], pleased to meet you 2019.11.29 16:34:12 LOG7[0]: <- 250-HELP 2019.11.29 16:34:12 LOG7[0]: <- 250-SIZE 36700160 2019.11.29 16:34:12 LOG7[0]: <- 250-ENHANCEDSTATUSCODES 2019.11.29 16:34:12 LOG7[0]: <- 250-8BITMIME 2019.11.29 16:34:12 LOG7[0]: <- 250-STARTTLS 2019.11.29 16:34:12 LOG7[0]: <- 250 OK 2019.11.29 16:34:12 LOG7[0]: -> STARTTLS 2019.11.29 16:34:12 LOG7[0]: <- 220 2.0.0 Ready to start TLS 2019.11.29 16:34:12 LOG6[0]: SNI: sending servername: smtp.comcast.net 2019.11.29 16:34:12 LOG6[0]: Peer certificate not required 2019.11.29 16:34:12 LOG7[0]: TLS state (connect): before/connect initialization 2019.11.29 16:34:12 LOG7[0]: TLS state (connect): SSLv2/v3 write client hello A 2019.11.29 16:34:12 LOG7[0]: TLS state (connect): SSLv3 read server hello A 2019.11.29 16:34:12 LOG6[0]: Certificate verification disabled 2019.11.29 16:34:12 LOG6[0]: Certificate verification disabled 2019.11.29 16:34:12 LOG6[0]: Certificate verification disabled 2019.11.29 16:34:12 LOG6[0]: Certificate verification disabled 2019.11.29 16:34:12 LOG7[0]: TLS state (connect): SSLv3 read server certificate A 2019.11.29 16:34:12 LOG7[0]: TLS state (connect): SSLv3 read server key exchange A 2019.11.29 16:34:12 LOG6[0]: Client certificate not requested 2019.11.29 16:34:12 LOG7[0]: TLS state (connect): SSLv3 read server done A 2019.11.29 16:34:12 LOG7[0]: TLS state (connect): SSLv3 write client key exchange A 2019.11.29 16:34:12 LOG7[0]: TLS state (connect): SSLv3 write change cipher spec A 2019.11.29 16:34:12 LOG7[0]: TLS state (connect): SSLv3 write finished A 2019.11.29 16:34:12 LOG7[0]: TLS state (connect): SSLv3 flush data 2019.11.29 16:34:12 LOG7[0]: TLS state (connect): SSLv3 read server session ticket A 2019.11.29 16:34:12 LOG7[0]: TLS state (connect): SSLv3 read finished A 2019.11.29 16:34:12 LOG7[0]: New session callback 2019.11.29 16:34:12 LOG7[0]: Peer certificate was cached (6814 bytes) 2019.11.29 16:34:12 LOG6[0]: Session id: 11C16B28FFB4A3A4EDC164CA65C3F20A896BF61C4D3B09F571E4285CFD0C82B3 2019.11.29 16:34:12 LOG7[0]: 1 client connect(s) requested 2019.11.29 16:34:12 LOG7[0]: 1 client connect(s) succeeded 2019.11.29 16:34:12 LOG7[0]: 0 client renegotiation(s) requested 2019.11.29 16:34:12 LOG7[0]: 0 session reuse(s) 2019.11.29 16:34:12 LOG6[0]: TLS connected: new session negotiated 2019.11.29 16:34:12 LOG6[0]: TLSv1.2 ciphersuite: ECDHE-RSA-AES256-GCM-SHA384 (256-bit encryption) 2019.11.29 16:34:12 LOG7[0]: Compression: null, expansion: null 2019.11.29 16:34:12 LOG7[0]: -> AUTH PLAIN AGNhcmxvc3JyQGNvbWNhc3QubmV0AFNveTFjYXJpZHVybw== 2019.11.29 16:34:12 LOG7[0]: <- 500 command unrecognized 2019.11.29 16:34:12 LOG3[0]: PLAIN Authentication Failed 2019.11.29 16:34:12 LOG5[0]: Connection reset: 0 byte(s) sent to TLS, 0 byte(s) sent to socket 2019.11.29 16:34:12 LOG7[0]: Remote descriptor (FD=288) closed 2019.11.29 16:34:12 LOG7[0]: Local descriptor (FD=264) closed 2019.11.29 16:34:12 LOG7[0]: Service [SSLsmtp] finished (0 left)

2 1

undefined reference to `CRYPTO_set_id_callback'
by Somchai Smythe 28 Nov '19

28 Nov '19

How do I fix this? gcc -DHAVE_CONFIG_H -I. -I/usr/kerberos/include -I/usr/include -DLIBDIR='"/usr/lib/stunnel"' -DCONFDIR='"/etc/stunnel"' -O3 -m64 -march=x86-64 -mtune=generic -pipe -std=gnu17 -pthread -Wall -Wextra -Wpedantic -Wformat=2 -Wconversion -Wno-long-long -Wno-deprecated-declarations -fPIE -fstack-protector -D_FORTIFY_SOURCE=2 -MT stunnel-sthreads.o -MD -MP -MF .deps/stunnel-sthreads.Tpo -c -o stunnel-sthreads.o `test -f 'sthreads.c' || echo './'`sthreads.c sthreads.c: In function 'thread_id_init': sthreads.c:116:5: warning: implicit declaration of function 'CRYPTO_set_id_callback'; did you mean 'CRYPTO_set_locking_callback'? [-Wimplicit-function-declaration] 116 | CRYPTO_set_id_callback(stunnel_thread_id); | ^~~~~~~~~~~~~~~~~~~~~~ | CRYPTO_set_locking_callback ... libtool: link: ( cd ".libs" && rm -f "libstunnel.la" && ln -s "../libstunnel.la" "libstunnel.la" ) /usr/lib/gcc/x86_64-pc-linux-gnu/9.2.0/../../../../x86_64-pc-linux-gnu/bin/ld: stunnel-sthreads.o: in function `sthreads_init': sthreads.c:(.text+0xb0): undefined reference to `CRYPTO_set_id_callback' /usr/lib/gcc/x86_64-pc-linux-gnu/9.2.0/../../../../x86_64-pc-linux-gnu/bin/ld: stunnel-sthreads.o: in function `thread_id_init': sthreads.c:(.text+0x3a): undefined reference to `CRYPTO_set_id_callback' collect2: error: ld returned 1 exit status make[2]: *** [Makefile:550: stunnel] Error 1 I'm using openssl-1.1.1d if it matters.

2 4

"Address already in use" error
by Phil Smith III 25 Nov '19

25 Nov '19

Rebooted (Windows 7, fully patched) today and stunnel wouldn't start, said "Address already in use". Hmm.nothing much has changed. Rebooted again, same. Tinkered a bit, didn't see anything that looked meaningful. Went to look at deleted digests of this list, saw new version out, installed that, now it's happy. So.a mystery, at least to me; posting in case it helps someone else! .phsiii

1 0

segfault with v5.55
by Francois Robinette 22 Nov '19

22 Nov '19

I've seen other having the same issue without resolution so far... But we do have the same issue: stunnel[7886]: segfault at 21 ip 00007f70aa1efcea sp 00007f6fa7797978 error 6 in libpthread-2.12.so[7f70aa1e5000+17000]

2 4

Windows 10 stunnel does not accept options
by Clodoaldo Neto 22 Nov '19

22 Nov '19

Any option I try in stunnel 5.55 results the same. Say: PS C:\Program Files (x86)\stunnel\bin> .\stunnel \path\to\config\file [ ] Running on Windows 6.2 [ ] No limit detected for the number of clients [.] stunnel 5.55 on x64-pc-mingw32-gnu platform [.] Compiled/running with OpenSSL 1.1.1c 28 May 2019 [.] Threading:WIN32 Sockets:SELECT,IPv6 TLS:ENGINE,OCSP,PSK,SNI [ ] errno: (*_errno()) [ ] GUI message loop initialized [ ] Running on Windows 6.2 [.] Reading configuration from file stunnel.conf [.] UTF-8 byte order mark detected [ ] Compression disabled [ ] No PRNG seeding was required [ ] Initializing service [ssh] [ ] Ciphers: HIGH:!aNULL:!SSLv2:!DH:!kDHEPSK [ ] TLSv1.3 ciphersuites: TLS_CHACHA20_POLY1305_SHA256:TLS_AES_256_GCM_SHA384:TLS_AES_128_GCM_SHA256 [ ] TLS options: 0x02100004 (+0x00000000, -0x00000000) [ ] No certificate or private key specified [:] Service [ssh] needs authentication to prevent MITM attacks [ ] Initializing service [gmail-imap] [!] Service [gmail-imap]: TLS server needs a certificate [ ] Deallocating section defaults [!] Server is down Same with PS C:\Program Files (x86)\stunnel\bin> .\stunnel nonexistent or PS C:\Program Files (x86)\stunnel\bin> .\stunnel -help Regards, Clodoaldo

1 0