December 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?

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Re: [stunnel-users] CPU 100%
by Eric Eberhard 06 Nov '24

06 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.

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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.

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TPM based mutual tls authentication
by Nyiri, Gabor (Nokia - HU/Budapest) 07 Nov '23

07 Nov '23

Hi, Can you help me how to configure stunnel client to use TPM for mutual TLS authentication? I want to connect with mTLS to a remote server then make this connection available for localhost without mTLS. Thanks for your help in advance! Here is my configuration so far without TPM: debug = debug output = /tmp/stunnel.log foreground = yes [mtls_client] client = yes accept = 127.0.0.1:12019 sni = server-with-mtls.example.com checkHost = server-with-mtls.example.com connect = 1.2.3.4:443 verifyChain = yes CApath = /etc/ssl/certs/ cert = client.crt key = client.key Thanks & br, Gábor Nyíri,

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Stunnel 4 failing to connect to gmail
by Asif Iqbal 11 Dec '20

11 Dec '20

I am faling to connect to gmail. Not sure what that bind error means. iqbala@ghar:~$ sudo stunnel4 2008.12.15 13:53:17 LOG7[3839:3083650736]: Snagged 64 random bytes from /home/iqbala/.rnd 2008.12.15 13:53:17 LOG7[3839:3083650736]: Wrote 1024 new random bytes to /home/iqbala/.rnd 2008.12.15 13:53:17 LOG7[3839:3083650736]: RAND_status claims sufficient entropy for the PRNG 2008.12.15 13:53:17 LOG7[3839:3083650736]: PRNG seeded successfully 2008.12.15 13:53:17 LOG7[3839:3083650736]: Certificate: /etc/stunnel/stunnel.pem 2008.12.15 13:53:17 LOG7[3839:3083650736]: Certificate loaded 2008.12.15 13:53:17 LOG7[3839:3083650736]: Key file: /etc/stunnel/stunnel.pem 2008.12.15 13:53:17 LOG7[3839:3083650736]: Private key loaded 2008.12.15 13:53:17 LOG7[3839:3083650736]: SSL context initialized for service ssmtp 2008.12.15 13:53:17 LOG5[3839:3083650736]: stunnel 4.22 on i486-pc-linux-gnu with OpenSSL 0.9.8g 19 Oct 2007 2008.12.15 13:53:17 LOG5[3839:3083650736]: Threading:PTHREAD SSL:ENGINE Sockets:POLL,IPv6 Auth:LIBWRAP 2008.12.15 13:53:17 LOG6[3839:3083650736]: file ulimit = 1024 (can be changed with 'ulimit -n') 2008.12.15 13:53:17 LOG6[3839:3083650736]: poll() used - no FD_SETSIZE limit for file descriptors 2008.12.15 13:53:17 LOG5[3839:3083650736]: 500 clients allowed 2008.12.15 13:53:17 LOG7[3839:3083650736]: FD 10 in non-blocking mode 2008.12.15 13:53:17 LOG7[3839:3083650736]: FD 11 in non-blocking mode 2008.12.15 13:53:17 LOG7[3839:3083650736]: FD 12 in non-blocking mode 2008.12.15 13:53:17 LOG7[3839:3083650736]: SO_REUSEADDR option set on accept socket 2008.12.15 13:53:17 LOG3[3839:3083650736]: Error binding ssmtp to 74.125.93.111:587 2008.12.15 13:53:17 LOG3[3839:3083650736]: bind: Cannot assign requested address (99) Here is how my conf file looks like iqbala@ghar:~$ cat /etc/stunnel/stunnel.conf | egrep -v "^;|^$" cert = /etc/stunnel/stunnel.pem foreground = yes sslVersion = SSLv3 chroot = /var/lib/stunnel4/ setuid = stunnel4 setgid = stunnel4 pid = /stunnel4.pid socket = l:TCP_NODELAY=1 socket = r:TCP_NODELAY=1 debug = 7 output = /var/log/stunnel4/stunnel.log client = yes [ssmtp] accept = smtp.gmail.com:587 connect = 25 Asif Iqbal PGP Key: 0xE62693C5 KeyServer: pgp.mit.edu

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Stunnel & 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

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stunnel4-5.50 start failed
by Hanhan lee 27 Dec '19

27 Dec '19

I compiled stunnel4-5.50 with openssl 1.1.1d. When I run stunnel, it will print some messages and stop: [ ] Clients allowed=500 [.] stunnel 5.50 on arm-none-linux-gnueabi platform [.] Compiled/running with OpenSSL 1.1.1d 10 Sep 2019 [.] Threading:PTHREAD Sockets:POLL,IPv6 TLS:ENGINE,FIPS,OCSP,PSK,SNI [ ] errno: (*__errno_location ()) [.] Reading configuration from file /conf/stunnel.conf [.] UTF-8 byte order mark not detected [.] FIPS mode disabled [ ] Compression disabled [ ] No PRNG seeding was required [ ] Initializing service [adviserd] [ ] Ciphers: AES256-SHA256:!RC4:HIGH:!MD5:!aNULL:!EDH:!AESGCM [ ] TLS options: 0x02104004 (+0x00004000, -0x00000000) [ ] Loading certificate from file: /conf/certs/server.pem [ ] Certificate loaded from file: /conf/certs/server.pem [ ] Loading private key from file: /conf/certs/privkey.pem [:] Insecure file permissions on /conf/certs/privkey.pem [ ] Private key loaded from file: /conf/certs/privkey.pem [ ] Private key check succeeded [ ] DH initialization needed for DHE-PSK-CHACHA20-POLY1305 [ ] DH initialization [ ] Could not load DH parameters from /conf/certs/server.pem [ ] Using dynamic DH parameters [ ] ECDH initialization [ ] ECDH initialized with curve prime256v1 [.] Configuration successful [ ] Binding service [adviserd] [ ] Listening file descriptor created (FD=8) [ ] Setting accept socket options (FD=8) [ ] Option SO_REUSEADDR set on accept socket [ ] Option TCP_NODELAY set on accept socket [ ] Service [adviserd] (FD=8) bound to :::7582 [!] Cannot open log file: /var/log/stunnel.log [ ] Deallocating section defaults [ ] Unbinding service [adviserd] [ ] Service [adviserd] closed (FD=8) [ ] Service [adviserd] closed [ ] Deallocating section [adviserd] I have no idea what's wrong with this, help! Many thanks

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Re: [stunnel-users] My home ISP blocking ssh protocol
by Eric Eberhard 13 Dec '19

13 Dec '19

Ditto. Eric -----Original Message----- From: stunnel-users [mailto:[email protected]] On Behalf Of Mike Sent: Thursday, December 12, 2019 9:08 AM To: stunnel-users(a)stunnel.org Subject: Re: [stunnel-users] My home ISP blocking ssh protocol On 12/11/2019 5:53 PM, Matt Thomas wrote: > Hello:) > >[snip > > All i am trying to do is have a SFTP server that i can access my dang >files from while i am at school, work, friends house, library or >wherever. >[snip] I run a ssh server on my home network. I configure it to use a port other than port 22. _______________________________________________ stunnel-users mailing list stunnel-users(a)stunnel.org https://www.stunnel.org/cgi-bin/mailman/listinfo/stunnel-users

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Stunnel-5.55 client close TLS socket before it could read more bytes
by Ming Lu 13 Dec '19

13 Dec '19

Hello, May I please have help on this issue? Thanks in advance! I had a stunnel server and client communicating with TLSv1.2 (both of them are stunnel 5.55 and OpenSSL-1.1.1d) on CentOS 7 based Linux (kernel was updated as 4.19.0). The case is that client sends a HTTP request to server, and then server responds a payload with more than 640KB size. Normally, the server will close the connection by sending an alert firstly. The issue is that sometimes (not 100% reproducible), stunnel client reported: "TLS socket closed (read hangup)". and then closed the TLS socket. So I could find an alert sent from client to server firstly from tcpdump. Consequently, this caused the application reported "unexpected end of input?" as there should be more data to be received. I added a few debug logic and I indeed found that: there were occurrences that if stunnel client did not close the TLS socket, it could read more data from TLS socket in next poll loop: -------------------- 03:59:46 localhost stunnel: LOG6[0]: MingL: POLLRDHUP: 8192 03:59:46 localhost stunnel: LOG6[0]: MingL: ioctlsocket: 0 03:59:46 localhost stunnel: LOG6[0]: MingL: bytes: 0 <== client didn't close the sock in my debug version. 03:59:46 localhost stunnel: LOG6[0]: MingL: after checking 03:59:46 localhost stunnel: LOG6[0]: MingL: s_poll_wait: return 1 03:59:46 localhost stunnel: LOG6[0]: MingL: sock_can_rd: n 03:59:46 localhost stunnel: LOG6[0]: MingL: sock_can_wr: Y 03:59:46 localhost stunnel: LOG6[0]: MingL: ssl_can_rd: n 03:59:46 localhost stunnel: LOG6[0]: MingL: ssl_can_wr: n 03:59:46 localhost stunnel: LOG6[0]: MingL: pending: 1 03:59:46 localhost stunnel: LOG6[0]: MingL: write to sock 18432 03:59:46 localhost stunnel: LOG6[0]: MingL: read_wants_read Y 03:59:46 localhost stunnel: LOG6[0]: MingL: write_wants_writen 03:59:46 localhost stunnel: LOG6[0]: MingL: read from TLS 10168 <== then I observed the further read from TLS. -------------------- Any help will be appreciated! Ming

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Re: [stunnel-users] My home ISP blocking ssh protocol
by Christopher Schultz 12 Dec '19

12 Dec '19

Matt, On 12/12/19 13:43, Matt Thomas wrote: > Not sure if you have read the first post, or maybe i didnt add it, but i > have tried port 22,5022,8022, 25565, 47506 and 443 haha. It wasn't clear if you were changing the port number of the sshd service (on your server) or the port you had open on your firewall/router. I suspect that your ISP is blocking incoming connections to port 22. The port number you use for sshd on the server is not relevant. -chris > On Thu, Dec 12, 2019, 9:44 AM Christopher Schultz > <chris(a)christopherschultz.net <mailto:[email protected]>> wrote: > > Matt, > > On 12/12/19 11:01, Matt Thomas wrote: > > Server is 192.168.0.10 > > Router is 192.168.0.1 > > > > It works fine internally:) > > > > I add a port forward in the router for port 22 pointed at .0.10. > Routers > > firewall all ready is configured to accept ssh on port 22 from any > any. > > > > When ever anyone attempts to connect to the server, a pop up shows > on my > > screen. When i try to have my friends or co-workers try from there > house > > or i try from public place, no pop up or hits on the server log. Just > > times out. > > > > But if i put minecraft on port 22, it works. So certain traffic is > > making it through. Even hamachi vpn works fine BUT i cant install that > > on public PC's haha > > I was about to say "this is clearly an issue with the port number, pick > something other than 22" but if you say you can run Minecraft over port > 22, then that's ... strange. > > I wasn't aware that Minecraft servers could have their ports changed > like that. You can really set up your Minecraft server to listen on > localhost:22 and it doesn't use UPnP or anything like that to > reconfigure your firewall/router? > > My advice is to try configuring things like this: > > Router: 192.168.0.1 > Forward WAN connections to port e.g. 1022 -> 192.168.0.10:1022 > <http://192.168.0.10:1022> > > Server: 192.68.0.1 > Accept stunnel connections on port 1022 > accept=:1022 > connect=localhost:22 > > If that works, I might even try just changing the port number of your > ssh/sftp service from the "standard" port to something else and trying > again without stunnel in the mix. > > I've never encountered an ISP which does deep packet inspection to block > services. They usually just block ports. > > -chris > > > On Thu, Dec 12, 2019, 7:58 AM Christopher Schultz > > <chris(a)christopherschultz.net > <mailto:[email protected]> > <mailto:[email protected] > <mailto:[email protected]>>> wrote: > > > > Matt, > > > > On 12/11/19 17:53, Matt Thomas wrote: > > > I need to know if Stunnel is going to accomplish what i need > to do. My > > > home ISP blocks protocol HTTP and SSH from coming in so that > > people cant > > > run their own website from home without paying the ISP for a > > "Business" line > > > > > > All i am trying to do is have a SFTP server that i can > access my dang > > > files from while i am at school, work, friends house, library or > > > wherever. I have tried ssh on multiple random ports and made > sure all > > > firewall rules and port forward rules were correct in my home > > router. I > > > know they work because i even went as far as setting up a > minecraft > > > server to just test the port forward rules out and sure > enough, my > > > friend 200 miles away can connect just fine to my home minecraft > > > server.. But he can not connect to the ssh server. No logs > are ever > > > created on the server either because something is stoping > the packet > > > from even hitting my router, that something is my ISP > > > > > > Would stunnel allow me to make ssh traffic look like regular > https > > > traffic, thus allowing me to connect to my server at home so > i can > > do my > > > homework?? > > > > Those other servers probably use TLS or plaintext connections. > stunnel > > uses TLS, but ssh/sftp use a slightly different protocol that may > > possibly be distinguishable by a determined ISP. > > > > I would think that using stunnel to tunnel SFTP/SSH would be > possible, > > though not strictly necessary. I suspect some other problem is > > preventing you from succeeding. > > > > Can you be more specific about exactly what you did for > configuration? > > Port numbers, specific things you did, etc? You don't have to > disclose > > your public IP address, but perhaps give the local IPs of your > router > > and home server, etc? > > > > -chris > > > > _______________________________________________ > > stunnel-users mailing list > > stunnel-users(a)stunnel.org <mailto:[email protected]> > <mailto:[email protected] <mailto:[email protected]>> > > https://www.stunnel.org/cgi-bin/mailman/listinfo/stunnel-users > > > > _______________________________________________ > stunnel-users mailing list > stunnel-users(a)stunnel.org <mailto:[email protected]> > https://www.stunnel.org/cgi-bin/mailman/listinfo/stunnel-users >

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