GnuTLS

GnuTLS (/ˈɡnuː ˌtiː ˌɛl ˈɛs/, the GNU Transport Layer Security Library) is a free software implementation of the SSL, TLS and DTLS protocols. It offers an application programming interface (API) for applications to enable secure communication over their network transport layer, as well as interfaces to access X.509, PKCS #12, OpenPGP and other structures. Although originally created for the GNU Project, its maintainer disassociated it from GNU in December 2012 after disputes with the Free Software Foundation over certain policies.^[2]

Features

GnuTLS consists of:

• a library that allows client applications to start secure sessions using the available protocols
• command-line tools, including:
  • an X.509 certificate manager
  • test client and server
  • random key and password generators

As of 2011 administrators can configure Apache web server to use GnuTLS so as to support TLS 1.2.^[3]

GnuTLS has the following features:

• SSL 3.0, TLS 1.0, TLS 1.1, TLS 1.2 protocols
• Datagram TLS (DTLS) 1.0, 1.2
• Secure remote password protocol (SRP) for TLS authentication
• Pre-shared key (PSK) for TLS authentication
• X.509 and OpenPGP certificate^[4] handling
• CPU assisted cryptography and cryptographic accelerator support (/dev/crypto), VIA PadLock and AES-NI instruction sets^[5]
• Support for smart cards and for hardware security modules
• Storage of cryptographic keys in the system's Trusted Platform Module (TPM)

License and motivation

The GnuTLS library is licensed under the GNU Lesser General Public License; included applications use the GNU General Public License.

GnuTLS was initially created to allow applications of the GNU Project to use secure protocols such as TLS. Although OpenSSL already existed, OpenSSL's license is not compatible with the GPL;^[6] thus software under the GPL, such as GNU software, could not use OpenSSL without making a GPL linking exception.

Deployment

Software packages using GnuTLS include(d):

• GNOME
• CenterIM
• Exim^[7]
• Weechat
• Mutt
• wireshark
• slrn
• Lynx^[7]
• CUPS
• gnoMint^[7]
• Emacs

See also

• Comparison of TLS implementations
• wolfSSL (previously CyaSSL)
• mbed TLS (previously PolarSSL)
• Network Security Services

References

External links

• Official website
• GNU Friends - An Interview with GNU TLS developer Nikos Mavroyanopoulos — a 2003 interview
• Fellowship interview with Simon Josefsson — a 2009 interview

GNU Project History GNU Manifesto Free Software Foundation Europe India Latin America History of free software Licenses GNU General Public License GNU Lesser General Public License Affero General Public License GNU Free Documentation License GPL linking exception Guidelines GNU Free System Distribution Guidelines Software GNU (variants) Hurd Linux-libre glibc Bash coreutils findutils Build system GCC binutils GDB GRUB GNOME GNUstep GIMP GNU Emacs GNU TeXmacs GNU Octave GNU R GSL GMP GNU Electric GNU Archimedes GNUnet GNU Privacy Guard Gnuzilla (IceCat) GNU Health GNUmed GNU LilyPond GNU Go GNU Chess Gnash more... Public speakers Alexandre Oliva Benjamin Mako Hill Bradley M. Kuhn Eben Moglen Federico Heinz Georg C. F. Greve John Sullivan Loïc Dachary Nagarjuna G. Ricardo Galli Richard Stallman Robert J. Chassell Other topics GNU/Linux naming controversy Revolution OS Free Software Foundation anti-Windows campaigns Defective by Design