Stunnel 5.26
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Stunnel 5.26 | 3.5 Mb
Stunnel is a program created to allow secure client-server transfers. Its purpose is to provide encryption via SSL (secure socket layer) to inetd daemons such as POP2, POP3, and IMAP servers. It can be used with standalone daemons (NNTP, SMTP and HTTP) and tunnelling PPP over network sockets, too.
Since the application is not intended for the average user solid knowledge about encrypted transfers and client server relationship is required.
Getting the tool on the system
Installing the tool on the system is not a tough job, but the operation requires a couple of stops that allow the user to select the components to be added as well as to provide information to be added to the certificate request.
During the installation procedure there is the possibility to include self-signed certificate tools and a terminal version of the application for sending the necessary commands.
Details about the country, state, and city or localhost are also requested, but some of the fields may be left blank.
Setting up the utility
The most important part in stunnel is its configuration. Setting everything up can be done from the main application window, which also lists a brief log of the operations carried out.
Customizing the connection should not be a difficult job for a more advanced user, especially since most of the options are accompanied by tooltips and the configuration is based on a demo file.
Among the options available there is the possibility to enable FIPS 140-2 mode, a security standard for validating cryptographic modules. Furthermore, at least one service must also be defined in the configuration file. Once the program started, the terminal window informs the user of the current setup.
Straightforward SSL encryption wrapper
stunnel may appear like a simple application, but the most difficult part is knowing what it is suitable for; and this information is reserved for system administrators.
FEATURES
Portability (Threading Models)
PTHREAD (Posix)
FORK (traditional Unix)
UCONTEXT (userlevel)
Performance and Scalability
Load sharing among multiple backend servers
External session cache (for clusters)
Compression (for limited bandwidth)
Support for OpenSSL Security Features
Certificate-based access control
CRL and OCSP certificate revocation
SNI (Server Name Indication) support for name-based virtual servers
PFS (Perfect Forward Secrecy) with DH and ECDH key agreement
FIPS mode (for compliance)
Configuration of hardware engines
Features Specific to Unix Platform
Local mode (running services designed for inetd) with optional pseudo-terminal allocation
chroot (additional security)
setuid/setgid (additional security)
Logging to syslog
Libwrap (TCP Wrappers) access control
Transparent proxy on selected platforms
EGD (Entropy Gathering Daemon) client
Unix socket support
Features Specific to Windows Platform
GUI
Saving cached peer certificate chains to files
Windows service mode
Other Features
IPv6 support
Protocol negotiation for cifs, connect, imap, nntp, pgsql, pop3, proxy, and smtp
Delayed resolver (for dialup connections and remote hosts with dynamic IP addresses)
Graceful configuration file reloading
Graceful log file reopening
Ident access control
New in version 5.26 (November 6, 2015)
- official site does not provide any info about changes in this version
OS: Windows All