gnu: Add libtmcg.

* gnu/packages/openpgp.scm: New file.

Signed-off-by: Ludovic Courtès <ludo@gnu.org>

gnu/local.mk

@@ -405,6 +405,7 @@ GNU_SYSTEM_MODULES =				\
   %D%/packages/openbox.scm			\
   %D%/packages/opencog.scm			\
   %D%/packages/openldap.scm			\
+  %D%/packages/openpgp.scm			\
   %D%/packages/openstack.scm			\
   %D%/packages/orpheus.scm			\
   %D%/packages/ots.scm				\

gnu/packages/openpgp.scm

@@ -0,0 +1,55 @@
+;;; GNU Guix --- Functional package management for GNU
+;;; Copyright © 2020 Justus Winter <justus@sequoia-pgp.org>
+;;;
+;;; This file is part of GNU Guix.
+;;;
+;;; GNU Guix is free software; you can redistribute it and/or modify it
+;;; under the terms of the GNU General Public License as published by
+;;; the Free Software Foundation; either version 3 of the License, or (at
+;;; your option) any later version.
+;;;
+;;; GNU Guix is distributed in the hope that it will be useful, but
+;;; WITHOUT ANY WARRANTY; without even the implied warranty of
+;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;;; GNU General Public License for more details.
+;;;
+;;; You should have received a copy of the GNU General Public License
+;;; along with GNU Guix.  If not, see <http://www.gnu.org/licenses/>.
+
+(define-module (gnu packages openpgp)
+  #:use-module (guix packages)
+  #:use-module (guix download)
+  #:use-module (guix build-system gnu)
+  #:use-module ((guix licenses) #:prefix license:)
+  #:use-module (gnu packages gnupg)
+  #:use-module (gnu packages multiprecision))
+
+(define-public libtmcg
+  (package
+    (name "libtmcg")
+    (version "1.3.18")
+    (source (origin
+              (method url-fetch)
+              (uri (string-append "mirror://savannah/libtmcg/libTMCG-" version
+                                  ".tar.gz"))
+              (sha256
+               (base32
+                "179b5jx3mqs9hgsj8cfwk6x8qib60kw9szk9fkz6s1gl3v83mnyx"))))
+    (build-system gnu-build-system)
+    (arguments '(#:configure-flags '("--enable-silent-rules")))
+    (inputs `(("gmp" ,gmp)
+              ("libgcrypt" ,libgcrypt)))
+    (synopsis
+     "C++ library for creating secure and fair online card games")
+    (description
+     "The library provides a sort of useful classes, algorithms, and
+high-level protocols to support an application programmer in writing such
+software.  The most remarkable feature is the absence of a trusted third
+party (TTP), i.e. neither a central game server nor trusted hardware
+components are necessary.
+
+The corresponding cryptographic problem, actually called Mental Poker, has
+been studied since 1979 (Shamir, Rivest, and Adleman) by many authors.
+LibTMCG provides the first practical implementation of such protocols.")
+    (home-page "https://www.nongnu.org/libtmcg/")
+    (license license:gpl2+)))