Stunnel Binaries

As is unix tradition, there are no precompiled unix binaries available. You should be able to compile Stunnel using any ANSI C compiler (for example the free gcc compiler) on your system natively.

However, since C compilers are less common in the Windows environment, you can download these precompiled Windows binaries for stunnel.

Files with a .asc extension are detached PGP signatures. As of Stunnel version 3.8, Michal has begun PGP signing the Stunnel tarballs and executables. You can get a copy of his PGP public key on his home page. PGP keys for Brian Hatch can be found here, and the key used for Stunnel-3.x branch is available here.

The most recent stable Stunnel version is flagged with a red asterisk (*). You may want to check out the ChangeLog file to see what differences exist between versions.

Stunnel-4.x

Stunnel-4.x is the most current and actively developed branch of Stunnel.

   Bytes      Timestamp       Filename
________ ____________________ ____________________________
     189 Feb 27 16:02:51 2005  stunnel-4.08.exe.asc
   78848 Feb 27 16:02:51 2005 *stunnel-4.08.exe
     189 Jan  2 17:57:16 2005  stunnel-4.07.exe.asc
   78336 Jan  2 17:57:16 2005  stunnel-4.07.exe
     189 Dec 25 17:17:51 2004  stunnel-4.06.exe.asc
   77824 Dec 25 17:17:51 2004  stunnel-4.06.exe
     189 Feb 14 07:26:38 2004  stunnel-4.05.exe.asc
   66048 Feb 14 07:26:38 2004  stunnel-4.05.exe
     189 Jan 12 08:54:54 2003  stunnel-4.04.exe.asc
   59904 Jan 12 08:54:54 2003  stunnel-4.04.exe
     254 Oct 30 20:45:42 2002  stunnel-4.03.exe.asc
   57856 Oct 30 20:45:42 2002  stunnel-4.03.exe
     254 Oct 21 12:14:10 2002  stunnel-4.02.exe.asc
   57344 Oct 21 12:14:10 2002  stunnel-4.02.exe
     254 Oct 20 15:33:42 2002  stunnel-4.01.exe.asc
   57856 Oct 20 15:33:42 2002  stunnel-4.01.exe
     254 Aug 30 12:38:04 2002  stunnel-4.00.exe.asc
   55296 Aug 30 12:38:04 2002  stunnel-4.00.exe

Stunnel-3.x

Stunnel-3.x is no longer under development, however we will continue to provide bugfixes as needed. All new development is on Stunnel-4.x, so you should switch to the new version when possible.

   Bytes      Timestamp       Filename
________ ____________________ ____________________________
     189 Aug 29 21:47:22 2003  stunnel-3.26.exe.asc
   51200 Aug 29 21:47:22 2003  stunnel-3.26.exe
     189 Aug  1 21:56:26 2003  stunnel-3.25.exe.asc
   51200 Aug  1 21:56:26 2003  stunnel-3.25.exe
     189 Jul 25 16:41:02 2003  stunnel-3.25-beta1.exe.asc
   51200 Jul 25 16:41:02 2003  stunnel-3.25-beta1.exe
     232 Apr 23 23:34:23 2003  stunnel-3.24.exe.asc
   41472 Apr 23 23:34:23 2003  stunnel-3.24.exe
     232 Apr  3 17:53:04 2003  stunnel-3.19.exe.asc
   31232 Apr  3 17:53:04 2003  stunnel-3.19.exe
     232 Apr  3 17:50:07 2003  stunnel-3.23.exe.asc
   41472 Apr  3 17:50:07 2003  stunnel-3.23.exe
     254 Dec 23 18:38:51 2001  stunnel-3.22.exe.asc
   40448 Dec 23 18:38:51 2001  stunnel-3.22.exe
     232 Nov 11 13:30:03 2001  stunnel-3.21c.exe.asc
   38912 Nov 11 13:30:03 2001  stunnel-3.21c.exe
     254 Nov  5 12:38:03 2001  stunnel-3.21b.exe.asc
     254 Nov  5 12:38:03 2001  stunnel-3.21a.exe.asc
     254 Nov  5 12:38:03 2001  stunnel-3.21.exe.asc
   38400 Nov  5 12:38:03 2001  stunnel-3.21b.exe
   38400 Nov  5 12:38:03 2001  stunnel-3.21a.exe
   38400 Nov  5 12:38:03 2001  stunnel-3.21.exe
     232 Aug 15 13:56:36 2001  stunnel-3.20.exe.asc
   31744 Aug 15 13:56:36 2001  stunnel-3.20.exe
     240 Jul 31 18:09:29 2001  stunnel-3.18.exe.asc
   29696 Jul 31 18:09:29 2001  stunnel-3.18.exe
     240 Jul 29 20:48:36 2001  stunnel-3.17.exe.asc
   28672 Jul 29 20:48:36 2001  stunnel-3.17.exe
     240 Jul 22 21:21:41 2001  stunnel-3.16.exe.asc
   28672 Jul 22 21:21:41 2001  stunnel-3.16.exe
     240 Jul 15 17:00:41 2001  stunnel-3.15.exe.asc
   28160 Jul 15 17:00:41 2001  stunnel-3.15.exe
     240 Feb 22 10:12:49 2001  stunnel-3.14.exe.asc
   26624 Feb 22 10:12:19 2001  stunnel-3.14.exe
     240 Jan 25 05:20:39 2001  stunnel-3.13.exe.asc
   26624 Jan 25 05:19:48 2001  stunnel-3.13.exe
     240 Jan 24 16:24:13 2001  stunnel-3.12.exe.asc
   26624 Jan 24 16:24:02 2001  stunnel-3.12.exe
     240 Dec 21 11:33:42 2000  stunnel-3.11.exe.asc
   26624 Dec 21 11:33:42 2000  stunnel-3.11.exe
   26624 Dec 19 11:44:35 2000  stunnel-3.10.exe
     240 Dec 19 11:44:16 2000  stunnel-3.10.exe.asc
     240 Dec 16 15:17:00 2000  stunnel-3.10beta1.exe.asc
   26112 Dec 16 15:17:00 2000  stunnel-3.10beta1.exe
     240 Dec 13 20:20:00 2000  stunnel-3.9.exe.asc
   25088 Dec 13 20:20:00 2000  stunnel-3.9.exe
     240 Jun 25 15:15:37 2000  stunnel-3.8p4.exe.asc
   24576 Jun 25 15:12:55 2000  stunnel-3.8p4.exe
     240 Jun 13 15:08:33 2000  stunnel-3.8p2.exe.asc
   23040 Jun 13 14:58:27 2000  stunnel-3.8p2.exe
     228 Feb 24 12:41:00 2000  stunnel-3.8.exe.asc
   19968 Feb 24 12:41:00 2000  stunnel-3.8.exe
   19968 Feb 10 12:38:00 2000  stunnel-3.7.exe
   19968 Feb  4 14:10:00 2000  stunnel-3.6.exe
   19456 Feb  2 12:37:00 2000  stunnel-3.5.exe
   19968 Jul 13 00:00:00 1999  stunnel-3.4a.exe
   19968 Jul 12 00:00:00 1999  stunnel-3.4.exe

OpenSSL Libraries

You will also require an SSL library. We suggest you use the most recent OpenSSL-0.9.7X version. If you do not already have DLLs from your own OpenSSL or SSLeay compilation, you can use these DLLs. The zip file is simply the lib* files zipped into one archive. (Not all versions of OpenSSL work with all versions of Stunnel. OpenSSL-0.9.7X or later is needed for Stunnel 4.04 and later.)

   Bytes      Timestamp       Filename
________ ____________________ ____________________________
     189 Nov  2 14:44:50 2004  libssl32.dll.asc
  633646 Nov  2 14:44:50 2004  libssl32.dll
     189 Nov  2 14:44:50 2004  libeay32.dll.asc
 1554300 Nov  2 14:44:50 2004  libeay32.dll
     189 Nov  2 14:44:50 2004  openssl.zip.asc
 1349010 Nov  2 14:44:50 2004  openssl.zip
     189 Nov  2 14:44:50 2004  openssl.exe.asc
 1144832 Nov  2 14:44:50 2004  openssl.exe

Note that these DLLs were compiled by Mike or Brian using the default OpenSSL compile-time options, thus these binaries may be inappropriate for your use depending on your local cryptography laws, patents on algorithms available in the DLLs, or other reasons.

You may want to use this Sample Stunnel Server Certificate for testing. We strongly suggest you generate your own Server Certificate once done testing. To do so, please read the Certificate Section of the FAQ. If you wish to generate your own stunnel.pem and cannot do it with the libraries above, as a last resort you con generate one online.

Compatibility Note

The above DLLs will only work with stunnel versions 3.8p1 and later since previous versions of Stunnel did not properly seed the Pseudo Random Number Generator.

If you must use an older stunnel version (which is not advised,) you must use the OpenSSL 0.9.5 or previous DLLs (available in the windows download directory)

Realize, however, that not using strong random seeds means that your session is not as cryptographically secure as it should be.

The Stunnel software package does not contain any cryptography itself, however please remember that import and/or export of cryptographic software, code providing hooks to cryptographic algorithms, and discussion about cryptography is illegal in some countries. It is imperative for you to know your local laws governing cryptography. We're not liable for anything you do that violates your local laws.