Libgcrypt - The GNU Crypto Library
------------------------------------
Version 1.6
Copyright (C) 1989,1991-2012 Free Software Foundation, Inc.
Copyright (C) 2012-2013 g10 Code GmbH
Copyright (C) 2013 Jussi Kivilinna
Libgcrypt is free software. See the file AUTHORS for full copying
notices, and LICENSES for notices about contributions that require
these additional notices to be distributed.
Overview
--------
Libgcrypt is a general purpose crypto library based on the code
used in GnuPG. Libgcrypt depends on the library `libgpg-error',
which must be installed correctly before Libgcrypt is to be built.
Libgcrypt is distributed under the LGPL, see the section "License"
below for details.
Build Instructions
------------------
The download canonical location for libgcrypt is:
ftp://ftp.gnupg.org/gcrypt/libgcrypt/
To build libgcrypt you need libgpg-error:
ftp://ftp.gnupg.org/gcrypt/libgpg-error/
You should get the latest versions of course.
After building and installing the libgpg-error package, you may
continue with Libgcrypt installation as with allmost all GNU
packages, you just have to do
./configure
make
make check
make install
The "make check" is not required but a good idea to see whether
the library works as expected. The check takes some while and
prints some benchmarking results. Before doing "make install" you
probably need to become root.
To build libgcrypt for Microsoft Windows, you need to have the
mingw32 cross-building toolchain installed. Instead of running a
plain configure you use
./autogen.sh --build-w32
make
make install
By default this command sequences expectsd a libgpg-error
installed below $HOME/w32root and installs libgcrypt to that
directory too. See the autogen.sh code for details.
The documentation is available as an Info file (gcrypt.info). To
build documentation in PDF, run this:
cd doc
make pdf
Mailing List
------------
You may want to join the developer's mailing list
gcrypt-devel@gnupg.org by sending mail with a subject of
"subscribe" to gcrypt-devel-request@gnupg.org. An archive of this
list is available at http://lists.gnupg.org .
Configure options
-----------------
Here is a list of configure options which are sometimes useful
for installation.
--enable-large-data-tests
With this option a "make check" will take really
long due to extra checks for the hash algorithms.
--enable-m-guard
Enable the integrated malloc checking code. Please
note that this feature does not work on all CPUs
(e.g. SunOS 5.7 on UltraSparc-2) and might give
you a bus error.
--disable-asm
Do not use assembler modules. It is not possible
to use this on some CPU types.
--enable-ld-version-script
Libgcrypt tries to build a library where internal
symbols are not exported. This requires support
from ld and is currently enabled for a few OSes.
If you know that your ld supports the so called
ELF version scripts, you can use this option to
force its use. OTOH, if you get error message
from the linker, you probably want to use this
option to disable the use of version scripts.
Note, that you should never ever use an
undocumented symbol or one which is prefixed with
an underscore.
--enable-ciphers=list
--enable-pubkey-ciphers=list
--enable-digests=list
If not otherwise specified, all algorithms
included in the libgcrypt source tree are built.
An exception are algorithms, which depend on
features not provided by the system, like 64bit
data types. With these switches it is possible
to select exactly those algorithm modules, which
should be built. The algorithms are to be
separated by spaces, commas or colons. To view
the list used with the current build the program
tests/version may be used.
--disable-endian-check
Don't let configure test for the endianness but
try to use the OS provided macros at compile
time. This is helpful to create OS X fat binaries.
--enable-random-daemon
Include support for a global random daemon and
build the daemon. This is an experimental feature.
--enable-mpi-path=EXTRA_PATH
Prepend EXTRA_PATH to list of CPU specific
optimizations. For example, if you want to add
optimizations forn a Intel Pentium 4 compatible
CPU, you may use
--enable-mpi-path=pentium4/sse2:pentium4/mmx
Take care: The generated library may crash on
non-compatible CPUs.
--enable-random=NAME
Force the use of the random gathering module
NAME. Default is either to use /dev/random or
the auto mode. Possible values for NAME are:
egd - Use the module which accesses the
Entropy Gathering Daemon. See the webpages
for more information about it.
unix - Use the standard Unix module which does not
have a very good performance.
linux - Use the module which accesses /dev/random.
This is the first choice and the default one
for GNU/Linux or *BSD.
auto - Compile linux, egd and unix in and
automagically select at runtime.
--enable-hmac-binary-check
Include support to check the binary at runtime
against a HMAC checksum. This works only in FIPS
mode and on systems providing the dladdr function.
--disable-padlock-support
Disable support for the PadLock engine of VIA
processors. The default is to use PadLock if
available. Try this if you get problems with
assembler code.
--disable-aesni-support
Disable support for the AES-NI instructions of
newer Intel CPUs. The default is to use AES-NI
if available. Try this if you get problems with
assembler code.
--disable-O-flag-munging
Some code is too complex for some compilers while
in higher optimization modes, thus the compiler
invocation is modified to use a lower
optimization level. Usually this works very well
but on some platforms these rules break the
invocation. This option may be used to disable
the feature under the assumption that either good
CFLAGS are given or the compiler can grok the code.
Build Problems
--------------
We can't check all assembler files, so if you have problems
assembling them (or the program crashes) use --disable-asm with
./configure. If you opt to delete individual replacement files in
hopes of using the remaining ones, be aware that the configure
scripts may consider several subdirectories to get all available
assembler files; be sure to delete the correct ones. Never delete
udiv-qrnnd.S in any CPU directory, because there may be no C
substitute (in mpi/genereic). Don't forget to delete
"config.cache" and run "./config.status --recheck". We got a few
reports about problems using versions of gcc earlier than 2.96
along with a non-GNU assembler (as). If this applies to your
platform, you can either upgrade gcc to a more recent version, or
use the GNU assembler.
Some make tools are broken - the best solution is to use GNU's
make. Try gmake or grab the sources from a GNU archive and
install them.
Specific problems on some machines:
* IBM RS/6000 running AIX
Due to a change in gcc (since version 2.8) the MPI stuff may
not build. In this case try to run configure using:
CFLAGS="-g -O2 -mcpu=powerpc" ./configure
* SVR4.2 (ESIX V4.2 cc)
Due to problems with the ESIX as(1), you probably want to do:
CFLAGS="-O -K pentium" ./configure --disable-asm
* SunOS 4.1.4
./configure ac_cv_sys_symbol_underscore=yes
* Sparc64 CPUs
We have reports about failures in the AES module when
compiling using gcc (e.g. version 4.1.2) and the option -O3;
using -O2 solves the problem.
License
-------
The library is distributed under the terms of the GNU Lesser
General Public License (LGPL); see the file COPYING.LIB for the
actual terms. The helper programs (e.g. gcryptrnd and getrandom)
as well as the documentation are distributed under the terms of
the GNU General Public License (GPL); see the file COPYING for the
actual terms. The file LICENSES has notices about contributions
that require these additional notices are distributed.
This library used to be available under the GPL - this was changed
with version 1.1.7 with the rationale that there are now many free
crypto libraries available and many of them come with capabilities
similar to Libcrypt. We decided that to foster the use of
cryptography in Free Software an LGPLed library would make more
sense because it avoids problems due to license incompatibilities
between some Free Software licenses and the GPL.
Please note that in many cases it is better for a library to be
licensed under the GPL, so that it provides an advantage for free
software projects. The Lesser GPL is so named because it does
less to protect the freedom of the users of the code that it
covers. See http://www.gnu.org/philosophy/why-not-lgpl.html for
more explanation.
Contact
-------
See the file AUTHORS.
Commercial grade support for Libgcrypt is available; please see
http://www.gnupg.org/service.html .
Commercial grade support for Libgcrypt is available; for a listing
of offers see http://www.gnupg.org/service.html . The driving
force behind the development of Libgcrypt is the company of its
principal author, Werner Koch. Maintenance and improvement of
Libgcrypt takes up a lot resources. To allow him to continue his
work, he asks to either purchase a support contract, engage them
for custom enhancements, or to donate money. See http://g10code.com .
This file is Free Software; as a special exception the authors gives
unlimited permission to copy and/or distribute it, with or without
modifications, as long as this notice is preserved. For conditions
of the whole package, please see the file COPYING. This file is
distributed in the hope that it will be useful, but WITHOUT ANY
WARRANTY, to the extent permitted by law; without even the implied
warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
