GnuTLS

GnuTLS consists of a library that allows client applications to start secure sessions using the available protocols.

It also provides command-line tools, including an X.509 certificate manager, a test client and server, and random key and password generators.

GnuTLS has the following features:

• TLS 1.3, TLS 1.2, TLS 1.1, TLS 1.0, and SSL 3.0 protocols
• Datagram TLS (DTLS) 1.2, and DTLS 1.0, protocols
• TLS-SRP: Secure remote password protocol (SRP) for TLS authentication
• TLS-PSK: Pre-shared key (PSK) for TLS authentication
• X.509 and OpenPGP certificate{{IETF RFC|6091}} handling
• CPU assisted cryptography and cryptographic accelerator support (/dev/crypto), VIA PadLock and AES-NI instruction sets[http://www.gnutls.org/ The GnuTLS Transport Layer Security Library]
• Support for smart cards and for hardware security modules
• Storage of cryptographic keys in the system's Trusted Platform Module (TPM)

GnuTLS was initially created around March{{Cite web |date=2000-03-07 |title=Initialized repository for GNU TLS (8aef5fff) · Commits · gnutls / GnuTLS · GitLab |url=https://gitlab.com/gnutls/gnutls/-/commit/8aef5fff2e54b67c694fa4ef9190cbedf1ff00c1 |access-date=2023-06-23 |website=GitLab |language=en}} to November{{Cite web |date=2000-11-15 |title=gnutls0-0-4 · Tags · gnutls / GnuTLS · GitLab |url=https://gitlab.com/gnutls/gnutls/-/tags/gnutls0-0-4 |access-date=2023-06-23 |website=GitLab |language=en}} 2000, by Nikos Mavrogiannopoulos 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;{{cite web | url = http://people.gnome.org/~markmc/openssl-and-the-gpl.html | title = The OpenSSL License and The GPL | date = 2004-06-22 | author = Mark McLoughlin | access-date = 2011-04-06 | df = dmy-all | archive-date = 2016-04-11 | archive-url = https://web.archive.org/web/20160411112314/https://people.gnome.org/~markmc/openssl-and-the-gpl.html | url-status = dead }} thus software under the GPL, such as GNU software, could not use OpenSSL without making a GPL linking exception.

The GnuTLS library was licensed originally under the GNU Lesser General Public License v2, while included applications to use the GNU General Public License.

In August 2011 the library was updated to the LGPLv3.[http://upstream.rosalinux.ru/changelogs/gnutls/3.2.1/changelog.html Version 2.99.4 (released 2011-07-23)[...] ** libgnutls: license upgraded to LGPLv3] After it was noticed{{cite web|url=http://nmav.gnutls.org/2013/03/the-perils-of-lgplv3.html |title=The perils of LGPLv3|first=Nikos |last=Mavrogiannopoulos |publisher=gnutls.org |date=2013-03-26 |access-date=2015-11-18 |quote=LGPLv3 is the latest version of the GNU Lesser General Public License. It follows the successful LGPLv2.1 license, and was released by Free Software Foundation as a counterpart to its GNU General Public License version 3. The goal of the GNU Lesser General Public Licenses is to provide software that can be used by both proprietary and free software. This goal has been successfully handled so far by LGPLv2.1, and there is a multitude of libraries using that license. Now we have LGPLv3 as the latest, and the question is how successful is LGPLv3 on this goal? In my opinion, very little. If we assume that its primary goal is to be used by free software, then it blatantly fails that. |df=dmy-all}} that there were new license compatibility problems introduced, especially with other free software with the license change, after discussions the license was downgraded again to LGPLv2.1 in March 2013.[http://www.gnutls.org/abi-tracker/changelog/gnutls/3.1.10/log.html 2013-03-14 Nikos Mavrogiannopoulos (nmav@gnutls.org) * COPYING.LESSER, README: gnutls 3.1.10 is LGPLv2.1]

GnuTLS was created for the GNU Project, but in December 2012 its maintainer, Nikos Mavrogiannopoulos, dissociated the project from GNU after policy disputes with the Free Software Foundation.[https://lwn.net/Articles/529522/ GnuTLS, copyright assignment, and GNU project governance] on lwn.net by Michael Kerrisk (December 20, 2012)

{{cite web | url = https://lwn.net/Articles/529558/ | title = gnutls is moving

| date = 2012-12-18

| author = Nikos Mavrogiannopoulos

| access-date = 2012-12-11 |df=dmy-all

}} Richard Stallman opposed this move and suggested forking the project instead.{{cite mailing list|url=https://lists.gnu.org/archive/html/gnutls-devel/2012-12/msg00003.html|title=GNUTLS is not going anywhere|date=2012-12-11|first=Richard|last=Stallman|mailing-list=gnutls-devel|quote=you cannot take GNUTLS out of the GNU Project. |df=dmy-all}} Soon afterward, developer Paolo Bonzini ended his maintainership of GNU Sed and Grep, expressing concerns similar to those of GnuTLS maintainer Mavrogiannopoulos.{{cite mailing list|url=https://lists.gnu.org/archive/html/bug-gnu-utils/2012-12/msg00011.html|title=GNU sed 4.2.2 released, and a rant from the maintainer|mailing-list=bug-gnu-utils|first=Paolo|last=Bonzini|date=2012-12-22 |df=dmy-all}}

{{More citations needed section|date=January 2015}}

Software packages using GnuTLS include(d):

• GNOME
• CenterIM
• Exim{{cite web|url=https://www.gnu.org/software/gnutls/programs.html|title=GnuTLS - GNU Project - Free Software Foundation (FSF)|date=22 May 2010|publisher=Free Software Foundation|archive-url=https://web.archive.org/web/20100531072839/https://www.gnu.org/software/gnutls/programs.html |archive-date=31 May 2010|access-date=25 January 2015}}
• WeeChat
• Mutt
• Wireshark
• slrn
• Lynx
• CUPS
• gnoMint
• GNU Emacs
• Synology DiskStation Manager
• OpenConnect{{cite web|url=http://www.infradead.org/openconnect/technical.html|title=OpenConnect VPN client technical details}}

{{Portal|Free and open-source software}}

• Comparison of TLS implementations
• wolfSSL (previously CyaSSL)
• mbed TLS (previously PolarSSL)
• List of free and open-source software packages
• Network Security Services

{{reflist|30em}}

• {{Official website}}
• [https://web.archive.org/web/20070821065252/http://www.network-theory.co.uk/articles/mavroyanopoulus.html GNU Friends - An Interview with GNU TLS developer Nikos Mavroyanopoulos] – a 2003 interview
• [https://blogs.fsfe.org/fellowship-interviews/?p=98 Fellowship interview with Simon Josefsson] – a 2009 interview

{{GNU}}

{{Cryptographic software}}

{{TLS/SSL}}

Category:Cryptographic software

Category:GNU Project software

Category:Free security software

Category:Transport Layer Security implementation