This also adds a Markdown version of README, mostly for GitHub.
- krb5-strength 3.0
+ krb5-strength 3.1
(Kerberos password strength checking plugin)
-
Maintained by Russ Allbery <eagle@eyrie.org>
- Copyright 2006, 2007, 2009, 2010, 2012, 2013, 2014 The Board of Trustees
- of the Leland Stanford Junior University. Portions copyright 1993 Alec
- Muffett. Developed by Derrick Brashear and Ken Hornstein of Sine Nomine
- Associates, on behalf of Stanford University. This software is
- distributed under a BSD-style license and under the Artistic License.
- Please see the section LICENSE for more information.
+ Copyright 2016 Russ Allbery <eagle@eyrie.org>. Copyright 2006-2007,
+ 2009-2010, 2012-2014 The Board of Trustees of the Leland Stanford Junior
+ University. Copyright 1993 Alec Muffett. This software is distributed
+ under a BSD-style license. Please see the section LICENSE below for
+ more information.
BLURB
krb5-strength provides a password quality plugin for the MIT Kerberos
- KDC (specifically the kadmind server), an external password quality
- program for use with Heimdal, and a per-principal password history
- implementation for Heimdal. Passwords can be tested with CrackLib,
- checked against a CDB or SQLite database of known weak passwords with
- some transformations, checked for length, checked for non-printable or
- non-ASCII characters that may be difficult to enter reproducibly,
- required to contain particular character classes, or any combination of
- these tests. It supports both Heimdal and MIT Kerberos (1.9 or later).
+ KDC (specifically the kadmind server) and Heimdal KDC, an external
+ password quality program for use with Heimdal, and a per-principal
+ password history implementation for Heimdal. Passwords can be tested
+ with CrackLib, checked against a CDB or SQLite database of known weak
+ passwords with some transformations, checked for length, checked for
+ non-printable or non-ASCII characters that may be difficult to enter
+ reproducibly, required to contain particular character classes, or any
+ combination of these tests.
DESCRIPTION
within edit distance one of a dictionary word. It can also impose other
programmatic checks on passwords such as character class requirements.
- For Heimdal, it includes both a program usable as an external password
- quality check and a plugin that implements the dynamic module API. For
- MIT Kerberos (1.9 or later), it includes a plugin for the password
- quality (pwqual) plugin API.
+ If you're just now starting with password checking, I recommend using
+ the SQLite database with a large wordlist and minimum password lengths.
+ We found this produced the best results with the least user frustration.
+
+ For Heimdal, krb5-strength includes both a program usable as an external
+ password quality check and a plugin that implements the dynamic module
+ API. For MIT Kerberos (1.9 or later), it includes a plugin for the
+ password quality (pwqual) plugin API.
krb5-strength can be built with either the system CrackLib or with the
modified version of CrackLib included in this package. Note, however,
the distribution a strength-checking plugin and an external password
check program that use the system CrackLib. With Heimdal, it would
probably be easier to use that plugin or program than build this package
- unless you want the modified CrackLib.
+ unless you want the modified CrackLib, one of the other dictionary
+ types, or the additional character class and length checks.
For information about the changes to the CrackLib included in this
toolkit, see cracklib/HISTORY. The primary changes are tighter rules,
which are more aggressive at finding dictionary words with characters
appended and prepended, which tighten the requirements for password
entropy, and which add stricter rules for longer passwords. They are
- also minor changes to fix portability issues and remove some code that
- doesn't make sense in the kadmind context.
-
- Ideally, the changes to CrackLib should be added to the standard
- CrackLib distribution by adding an additional interface to configure its
- behavior, at which point this package can likely wither away in favor of
- much simpler plugins that link to the standard CrackLib library.
+ also minor changes to fix portability issues, remove some code that
+ doesn't make sense in the kadmind context, and close a few security
+ issues. The standard CrackLib distribution on at least some Linux
+ distributions now supports an additional interface to configure its
+ behavior, and krb5-strength should change in the future to use that
+ interface and drop the embedded copy.
krb5-strength also includes a password history implementation for
Heimdal. This is separate from the password strength implementation but
version should be supported, but note that some versions, particularly
older versions close to the original code, do things like printing
diagnostics to stderr, calling exit, and otherwise not being
- well-behaved for use inside plugins or libraries. If using a system
- CrackLib library, use version 2.8.22 or later to avoid these problems.
+ well-behaved for use inside plugins or libraries. They also have known
+ security vulnerabilities. If using a system CrackLib library, use
+ version 2.8.22 or later to avoid these problems.
You can also optionally build against the TinyCDB library, which
provides support for simpler and faster password checking against a CDB
The password history program, heimdal-history, requires Perl 5.010 or
later plus the following CPAN modules:
- DB_File::Lock
- Crypt::PBKDF2
- Getopt::Long::Descriptive
- IPC::Run
- JSON
- Readonly
+ * DB_File::Lock
+ * Crypt::PBKDF2
+ * Getopt::Long::Descriptive
+ * IPC::Run
+ * JSON
+ * Readonly
and their dependencies.
dependencies of the heimdal-history program. The following additional
Perl modules will also be used by the test suite if present:
- Perl6::Slurp
- Test::MinimumVersion
- Test::Perl::Critic
- Test::Pod
- Test::Spelling
- Test::Strict
+ * Perl6::Slurp
+ * Test::MinimumVersion
+ * Test::Perl::Critic
+ * Test::Pod
+ * Test::Spelling
+ * Test::Strict
All are available on CPAN. Some tests will be skipped if the modules
are not available.
many problems, set the environment variable AUTHOR_TESTING to a true
value.
- To bootstrap from a Git checkout, or If you change the Automake files
+ To bootstrap from a Git checkout, or if you change the Automake files
and need to regenerate Makefile.in, you will need Automake 1.11 or
later. For bootstrap or if you change configure.ac or any of the m4
files it includes and need to regenerate configure or config.h.in, you
will need Autoconf 2.64 or later. You will also need Perl 5.010 or
later and the DBI, DBD::SQLite, JSON, Perl6::Slurp, and Readonly modules
- (from CPAN) to bootstrap the test suite data from a Git checkout.
+ (from CPAN) to generate man pages and bootstrap the test suite data from
+ a Git checkout.
-COMPILING AND INSTALLING
+BUILDING AND INSTALLATION
- You can build and install the plugin with the standard commands:
+ You can build and install krb5-strength with the standard commands:
./configure
make
make install
- Pass --enable-silent-rules to configure for a quieter build (similar to
- the Linux kernel). Use make warnings instead of make to build with full
- GCC compiler warnings (requires a relatively current version of GCC).
+ If you are building from a Git clone, first run ./bootstrap in the
+ source directory to generate the build files. make install will
+ probably have to be done as root. Building outside of the source
+ directory is also supported, if you wish, by creating an empty directory
+ and then running configure with the correct relative path.
- The last step will probably have to be done as root. By default, the
- plugin is installed as /usr/local/lib/krb5/plugins/pwqual/strength.so
- and the Heimdal external password check function is installed as
- /usr/local/bin/heimdal-strength. You can change these paths with the
- --prefix, --libdir, and --bindir options to configure.
+ By default, the Heimdal external password check function is installed as
+ /usr/local/bin/heimdal-strength, and the plugin is installed as
+ /usr/local/lib/krb5/plugins/pwqual/strength.so. You can change these
+ paths with the --prefix, --libdir, and --bindir options to configure.
- To build with the system version of CrackLib, pass --with-cracklib to
- configure. You can optionally add a directory, giving the root
- directory where CrackLib was installed, or separately set the include
- and library path with --with-cracklib-include and --with-cracklib-lib.
+ By default, the embedded version of CrackLib will be used. To build
+ with the system version of CrackLib, pass --with-cracklib to configure.
+ You can optionally add a directory, giving the root directory where
+ CrackLib was installed, or separately set the include and library path
+ with --with-cracklib-include and --with-cracklib-lib.
krb5-strength will automatically build with TinyCDB if it is found. To
specify the installation path of TinyCDB, use --with-tinycdb. You can
--with-sqlite-include and --with-sqlite-lib.
Normally, configure will use krb5-config to determine the flags to use
- to compile with your Kerberos libraries. If krb5-config isn't found, it
- will look for the standard Kerberos libraries in locations already
- searched by your compiler. If the the krb5-config script first in your
- path is not the one corresponding to the Kerberos libraries you want to
- use or if your Kerberos libraries and includes aren't in a location
- searched by default by your compiler, you need to specify a different
- Kerberos installation root via --with-krb5=PATH. For example:
+ to compile with your Kerberos libraries. To specify a particular
+ krb5-config script to use, either set the PATH_KRB5_CONFIG environment
+ variable or pass it to configure like:
+
+ ./configure PATH_KRB5_CONFIG=/path/to/krb5-config
+
+ If krb5-config isn't found, configure will look for the standard
+ Kerberos libraries in locations already searched by your compiler. If
+ the the krb5-config script first in your path is not the one
+ corresponding to the Kerberos libraries you want to use, or if your
+ Kerberos libraries and includes aren't in a location searched by default
+ by your compiler, you need to specify a different Kerberos installation
+ root via --with-krb5=PATH. For example:
./configure --with-krb5=/usr/pubsw
need to do this if Autoconf can't figure out whether to use lib, lib32,
or lib64 on your platform.
- To specify a particular krb5-config script to use, either set the
- PATH_KRB5_CONFIG environment variable or pass it to configure like:
-
- ./configure PATH_KRB5_CONFIG=/path/to/krb5-config
-
To not use krb5-config and force library probing even if there is a
krb5-config script on your path, set PATH_KRB5_CONFIG to a nonexistent
path:
krb5-config is not used and library probing is always done if either
--with-krb5-include or --with-krb5-lib are given.
+ Pass --enable-silent-rules to configure for a quieter build (similar to
+ the Linux kernel). Use make warnings instead of make to build with full
+ GCC compiler warnings (requires a relatively current version of GCC).
+
You can pass the --enable-reduced-depends flag to configure to try to
minimize the shared library dependencies encoded in the binaries. This
- omits from the link line all the libraries included solely because the
- Kerberos libraries depend on them and instead links the programs only
- against libraries whose APIs are called directly. This will only work
- with shared Kerberos libraries and will only work on platforms where
- shared libraries properly encode their own dependencies (such as Linux).
- It is intended primarily for building packages for Linux distributions
- to avoid encoding unnecessary shared library dependencies that make
- shared library migrations more difficult. If none of the above made any
- sense to you, don't bother with this flag.
+ omits from the link line all the libraries included solely because other
+ libraries depend on them and instead links the programs only against
+ libraries whose APIs are called directly. This will only work with
+ shared libraries and will only work on platforms where shared libraries
+ properly encode their own dependencies (this includes most modern
+ platforms such as all Linux). It is intended primarily for building
+ packages for Linux distributions to avoid encoding unnecessary shared
+ library dependencies that make shared library migrations more difficult.
+ If none of the above made any sense to you, don't bother with this flag.
After installing this software, see the man pages for krb5-strength,
heimdal-strength, and heimdal-history for configuration information.
+TESTING
+
+ krb5-strength comes with a test suite, which you can run after building
+ with:
+
+ make check
+
+ If a test fails, you can run a single test with verbose output via:
+
+ tests/runtests -o <name-of-test>
+
+ Do this instead of running the test program directly since it will
+ ensure that necessary environment variables are set up.
+
SUPPORT
The krb5-strength web page at:
will always have the current version of this package, the current
documentation, and pointers to any additional resources.
- I welcome bug reports and patches for this package at eagle@eyrie.org.
+ For bug tracking, use the issue tracker on GitHub:
+
+ https://github.com/rra/krb5-strength/issues
+
However, please be aware that I tend to be extremely busy and work
- projects often take priority. I'll save your mail and get to it as soon
- as I can, but it may take me a couple of months.
+ projects often take priority. I'll save your report and get to it as
+ soon as I can, but it may take me a couple of months.
SOURCE REPOSITORY
krb5-strength is maintained using Git. You can access the current
- source by cloning the repository at:
+ source on GitHub at:
- git://git.eyrie.org/kerberos/krb5-strength.git
+ https://github.com/rra/krb5-strength
+
+ or by cloning the repository at:
+
+ https://git.eyrie.org/git/kerberos/krb5-strength.git
or view the repository via the web at:
- https://git.eyrie.org/?p=kerberos/krb5-strength.git
+ https://git.eyrie.org/?p=devel/krb5-strength.git
- When contributing modifications, either patches (possibly generated by
- git format-patch) or Git pull requests are welcome.
+ The eyrie.org repository is the canonical one, maintained by the author,
+ but using GitHub is probably more convenient for most purposes. Pull
+ requests are gratefully reviewed and normally accepted.
LICENSE
The krb5-strength package as a whole is covered by the following
copyright statement and license:
- Copyright 2006, 2007, 2009, 2010, 2012, 2013, 2014
+ Copyright 2016 Russ Allbery <eagle@eyrie.org>
+ Copyright 2006-2007, 2009-2010, 2012-2014
The Board of Trustees of the Leland Stanford Junior University
+ Copyright 1993 Alec Muffett
Permission is hereby granted, free of charge, to any person obtaining
a copy of this software and associated documentation files (the
TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
- The embedded version of CrackLib (all files in the cracklib
- subdirectory) is covered by the Artistic license. See the file
- cracklib/LICENCE for more information. Combined derivative works that
- include this code, such as binaries built with the embedded CrackLib,
- will need to follow the terms of the Artistic license as well as the
- above license.
+ Developed by Derrick Brashear and Ken Hornstein of Sine Nomine
+ Associates, on behalf of Stanford University.
- All other individual files without an explicit exception below are
- released under this license. Some files may have additional copyright
- holders as noted in those files. There is detailed information about
- the licensing of each file in the LICENSE file in this distribution.
+ The embedded version of CrackLib (all files in the cracklib
+ subdirectory) is covered by the Artistic license. See the file
+ cracklib/LICENCE for more information. Combined derivative works that
+ include this code, such as binaries built with the embedded CrackLib,
+ will need to follow the terms of the Artistic license as well as the
+ above license.
Some files in this distribution are individually released under
different licenses, all of which are compatible with the above general
package license but which may require preservation of additional
- notices. All required notices are preserved in the LICENSE file.
+ notices. All required notices, and detailed information about the
+ licensing of each file, are recorded in the LICENSE file.
+
+ For any copyright range specified by files in this package as YYYY-ZZZZ,
+ the range specifies every single year in that closed interval.
--- /dev/null
+# krb5-strength 3.1
+
+Copyright 2016 Russ Allbery <eagle@eyrie.org>. Copyright 2006-2007,
+2009-2010, 2012-2014 The Board of Trustees of the Leland Stanford Junior
+University. Copyright 1993 Alec Muffett. This software is distributed
+under a BSD-style license. Please see the section [License](#license)
+below for more information.
+
+## Blurb
+
+krb5-strength provides a password quality plugin for the MIT Kerberos KDC
+(specifically the kadmind server) and Heimdal KDC, an external password
+quality program for use with Heimdal, and a per-principal password history
+implementation for Heimdal. Passwords can be tested with CrackLib,
+checked against a CDB or SQLite database of known weak passwords with some
+transformations, checked for length, checked for non-printable or
+non-ASCII characters that may be difficult to enter reproducibly, required
+to contain particular character classes, or any combination of these
+tests.
+
+## Description
+
+Heimdal includes a capability to plug in external password quality checks
+and comes with an example that checks passwords against CrackLib.
+However, in testing at Stanford, we found that CrackLib with its default
+transform rules does not catch passwords that can be guessed using the
+same dictionary with other tools, such as Jack the Ripper. We then
+discovered other issues with CrackLib with longer passwords, such as some
+bad assumptions about how certain measures of complexity will scale, and
+wanted to impose other limitations that it didn't support.
+
+This plugin provides the ability to check password quality against the
+standard version of CrackLib, or against a modified version of CrackLib
+that only passes passwords that resist attacks from both Crack and Jack
+the Ripper using the same rule sets. It also supports doing simpler
+dictionary checks against a CDB database, which is fast with very large
+dictionaries, or a SQLite database, which can reject all passwords within
+edit distance one of a dictionary word. It can also impose other
+programmatic checks on passwords such as character class requirements.
+
+If you're just now starting with password checking, I recommend using the
+SQLite database with a large wordlist and minimum password lengths. We
+found this produced the best results with the least user frustration.
+
+For Heimdal, krb5-strength includes both a program usable as an external
+password quality check and a plugin that implements the dynamic module
+API. For MIT Kerberos (1.9 or later), it includes a plugin for the
+password quality (pwqual) plugin API.
+
+krb5-strength can be built with either the system CrackLib or with the
+modified version of CrackLib included in this package. Note, however,
+that if you're building against the system CrackLib, Heimdal includes in
+the distribution a strength-checking plugin and an external password check
+program that use the system CrackLib. With Heimdal, it would probably be
+easier to use that plugin or program than build this package unless you
+want the modified CrackLib, one of the other dictionary types, or the
+additional character class and length checks.
+
+For information about the changes to the CrackLib included in this
+toolkit, see `cracklib/HISTORY`. The primary changes are tighter rules,
+which are more aggressive at finding dictionary words with characters
+appended and prepended, which tighten the requirements for password
+entropy, and which add stricter rules for longer passwords. They are also
+minor changes to fix portability issues, remove some code that doesn't
+make sense in the kadmind context, and close a few security issues. The
+standard CrackLib distribution on at least some Linux distributions now
+supports an additional interface to configure its behavior, and
+krb5-strength should change in the future to use that interface and drop
+the embedded copy.
+
+krb5-strength also includes a password history implementation for Heimdal.
+This is separate from the password strength implementation but can be
+stacked with it so that both strength and history checks are performed.
+This history implementation is available only via the Heimdal external
+password quality interface. MIT Kerberos includes its own password
+history implementation.
+
+## Requirements
+
+For Heimdal, you may use either the external password quality check tool,
+installed as heimdal-strength, or the plugin as you choose. It has been
+tested with Heimdal 1.2.1 and later, but has not recently been tested with
+versions prior to 1.5.
+
+For MIT Kerberos, version 1.9 or higher is required for the password
+quality plugin interface. MIT Kerberos does not support an external
+password quality check tool directly, so you will need to install the
+plugin.
+
+You can optionally build against the system CrackLib library. Any version
+should be supported, but note that some versions, particularly older
+versions close to the original code, do things like printing diagnostics
+to stderr, calling exit, and otherwise not being well-behaved for use
+inside plugins or libraries. They also have known security
+vulnerabilities. If using a system CrackLib library, use version 2.8.22
+or later to avoid these problems.
+
+You can also optionally build against the TinyCDB library, which provides
+support for simpler and faster password checking against a CDB dictionary
+file, and the SQLite library (a version new enough to support the
+`sqlite3_open_v2` API; 3.7 should be more than sufficient), which provides
+support for checking whether passwords are within edit distance one of a
+dictionary word.
+
+For this module to be effective for either Heimdal or MIT Kerberos, you
+will also need to construct a dictionary. The `mkdict` and `packer`
+utilities to build a CrackLib dictionary from a word list are included in
+this toolkit but not installed by default. You can run them out of the
+`cracklib` directory after building. You can also use the utilities that
+come with the stock CrackLib package (often already packaged in a Linux
+distribution); the database format is compatible.
+
+For building a CDB or SQLite dictionary, use the provided
+`krb5-strength-wordlist` program. For CDB dictionries, the `cdb` utility
+must be on your `PATH`. For SQLite, the DBI and DBD::SQLite Perl modules
+are required. `krb5-strength-wordlist` requires Perl 5.006 or later.
+
+For a word list to use as source for the dictionary, you can use
+`/usr/share/dict/words` if it's available on your system, but it would be
+better to find a more comprehensive word list. Since word lists are
+bulky, often covered by murky copyrights, and easily locatable on the
+Internet with a modicum of searching, none are included in this toolkit.
+
+The password history program, heimdal-history, requires Perl 5.010 or
+later plus the following CPAN modules:
+
+* DB_File::Lock
+* Crypt::PBKDF2
+* Getopt::Long::Descriptive
+* IPC::Run
+* JSON
+* Readonly
+
+and their dependencies.
+
+To run the test suite, you will need Perl 5.010 or later and the
+dependencies of the `heimdal-history` program. The following additional
+Perl modules will also be used by the test suite if present:
+
+* Perl6::Slurp
+* Test::MinimumVersion
+* Test::Perl::Critic
+* Test::Pod
+* Test::Spelling
+* Test::Strict
+
+All are available on CPAN. Some tests will be skipped if the modules are
+not available.
+
+To enable tests that don't detect functionality problems but are used to
+sanity-check the release, set the environment variable `RELEASE_TESTING`
+to a true value. To enable tests that may be sensitive to the local
+environment or that produce a lot of false positives without uncovering
+many problems, set the environment variable `AUTHOR_TESTING` to a true
+value.
+
+To bootstrap from a Git checkout, or if you change the Automake files and
+need to regenerate Makefile.in, you will need Automake 1.11 or later. For
+bootstrap or if you change configure.ac or any of the m4 files it includes
+and need to regenerate configure or config.h.in, you will need Autoconf
+2.64 or later. You will also need Perl 5.010 or later and the DBI,
+DBD::SQLite, JSON, Perl6::Slurp, and Readonly modules (from CPAN) to
+generate man pages and bootstrap the test suite data from a Git checkout.
+
+## Building and Installation
+
+You can build and install krb5-strength with the standard commands:
+
+```
+ ./configure
+ make
+ make install
+```
+
+If you are building from a Git clone, first run `./bootstrap` in the
+source directory to generate the build files. `make install` will
+probably have to be done as root. Building outside of the source
+directory is also supported, if you wish, by creating an empty directory
+and then running configure with the correct relative path.
+
+By default, the Heimdal external password check function is installed as
+`/usr/local/bin/heimdal-strength`, and the plugin is installed as
+`/usr/local/lib/krb5/plugins/pwqual/strength.so`. You can change these
+paths with the `--prefix`, `--libdir`, and `--bindir` options to
+configure.
+
+By default, the embedded version of CrackLib will be used. To build with
+the system version of CrackLib, pass `--with-cracklib` to configure. You
+can optionally add a directory, giving the root directory where CrackLib
+was installed, or separately set the include and library path with
+`--with-cracklib-include` and `--with-cracklib-lib`.
+
+krb5-strength will automatically build with TinyCDB if it is found. To
+specify the installation path of TinyCDB, use `--with-tinycdb`. You can
+also separately set the include and library path with
+`--with-tinycdb-include` and `--with-tinycdb-lib`.
+
+Similarly, krb5-strength will automatically build with SQLite if it is
+found. To specify the installation path of SQLite, use `--with-sqlite`.
+You can also separately set the include and library path with
+`--with-sqlite-include` and `--with-sqlite-lib`.
+
+Normally, configure will use `krb5-config` to determine the flags to use
+to compile with your Kerberos libraries. To specify a particular
+`krb5-config` script to use, either set the `PATH_KRB5_CONFIG` environment
+variable or pass it to configure like:
+
+```
+ ./configure PATH_KRB5_CONFIG=/path/to/krb5-config
+```
+
+If `krb5-config` isn't found, configure will look for the standard
+Kerberos libraries in locations already searched by your compiler. If the
+the `krb5-config` script first in your path is not the one corresponding
+to the Kerberos libraries you want to use, or if your Kerberos libraries
+and includes aren't in a location searched by default by your compiler,
+you need to specify a different Kerberos installation root via
+`--with-krb5=PATH`. For example:
+
+```
+ ./configure --with-krb5=/usr/pubsw
+```
+
+You can also individually set the paths to the include directory and the
+library directory with `--with-krb5-include` and `--with-krb5-lib`. You
+may need to do this if Autoconf can't figure out whether to use lib,
+lib32, or lib64 on your platform.
+
+To not use krb5-config and force library probing even if there is a
+krb5-config script on your path, set PATH_KRB5_CONFIG to a nonexistent
+path:
+
+```
+ ./configure PATH_KRB5_CONFIG=/nonexistent
+```
+
+`krb5-config` is not used and library probing is always done if either
+`--with-krb5-include` or `--with-krb5-lib` are given.
+
+Pass `--enable-silent-rules` to configure for a quieter build (similar to
+the Linux kernel). Use make warnings instead of make to build with full
+GCC compiler warnings (requires a relatively current version of GCC).
+
+You can pass the `--enable-reduced-depends` flag to configure to try to
+minimize the shared library dependencies encoded in the binaries. This
+omits from the link line all the libraries included solely because other
+libraries depend on them and instead links the programs only against
+libraries whose APIs are called directly. This will only work with shared
+libraries and will only work on platforms where shared libraries properly
+encode their own dependencies (this includes most modern platforms such as
+all Linux). It is intended primarily for building packages for Linux
+distributions to avoid encoding unnecessary shared library dependencies
+that make shared library migrations more difficult. If none of the above
+made any sense to you, don't bother with this flag.
+
+After installing this software, see the man pages for krb5-strength,
+heimdal-strength, and heimdal-history for configuration information.
+
+## Testing
+
+krb5-strength comes with a test suite, which you can run after building
+with:
+
+```
+ make check
+```
+
+If a test fails, you can run a single test with verbose output via:
+
+```
+ tests/runtests -o <name-of-test>
+```
+
+Do this instead of running the test program directly since it will ensure
+that necessary environment variables are set up.
+
+## Support
+
+The [krb5-strength web
+page](https://www.eyrie.org/~eagle/software/krb5-strength/) will always
+have the current version of this package, the current documentation, and
+pointers to any additional resources.
+
+For bug tracking, use the [issue tracker on
+GitHub](https://github.com/rra/krb5-strength/issues). However, please be
+aware that I tend to be extremely busy and work projects often take
+priority. I'll save your mail and get to it as soon as I can, but it may
+take me a couple of months.
+
+## Source Repository
+
+krb5-strength is maintained using Git. You can access the current source
+on [GitHub](https://github.com/rra/krb5-strength) or by cloning the
+repository at:
+
+https://git.eyrie.org/git/kerberos/krb5-strength.git
+
+or [view the repository on the
+web](https://git.eyrie.org/?p=devel/krb5-strength.git).
+
+The eyrie.org repository is the canonical one, maintained by the author,
+but using GitHub is probably more convenient for most purposes. Pull
+requests are gratefully reviewed and normally accepted.
+
+## License
+
+The krb5-strength package as a whole is covered by the following copyright
+statement and license:
+
+> Copyright 2016
+> Russ Allbery <eagle@eyrie.org>
+>
+> Copyright 2006-2007, 2009-2010, 2012-2014
+> The Board of Trustees of the Leland Stanford Junior University
+>
+> Copyright 1993
+> Alec Muffett
+>
+> Permission is hereby granted, free of charge, to any person obtaining a
+> copy of this software and associated documentation files (the "Software"),
+> to deal in the Software without restriction, including without limitation
+> the rights to use, copy, modify, merge, publish, distribute, sublicense,
+> and/or sell copies of the Software, and to permit persons to whom the
+> Software is furnished to do so, subject to the following conditions:
+>
+> The above copyright notice and this permission notice shall be included in
+> all copies or substantial portions of the Software.
+>
+> THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+> IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+> FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+> THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+> LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+> FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+> DEALINGS IN THE SOFTWARE.
+>
+> Developed by Derrick Brashear and Ken Hornstein of Sine Nomine Associates,
+> on behalf of Stanford University.
+>
+> The embedded version of CrackLib (all files in the `cracklib`
+> subdirectory) is covered by the Artistic license. See the file
+> `cracklib/LICENCE` for more information. Combined derivative works that
+> include this code, such as binaries built with the embedded CrackLib, will
+> need to follow the terms of the Artistic license as well as the above
+> license.
+
+Some files in this distribution are individually released under different
+licenses, all of which are compatible with the above general package
+license but which may require preservation of additional notices. All
+required notices, and detailed information about the licensing of each
+file, are recorded in the LICENSE file.
+
+For any copyright range specified by files in this package as YYYY-ZZZZ,
+the range specifies every single year in that closed interval.
--- /dev/null
+This directory contains configuration for DocKnot used to generate
+documentation files (like README.md) and web pages. Other documentation
+in this package is generated automatically from these files as part of the
+release process. For more information, see DocKnot's documentation.
+
+DocKnot is available from <https://www.eyrie.org/~eagle/software/docknot/>.
--- /dev/null
+krb5-strength provides a password quality plugin for the MIT Kerberos KDC
+(specifically the kadmind server) and Heimdal KDC, an external password
+quality program for use with Heimdal, and a per-principal password history
+implementation for Heimdal. Passwords can be tested with CrackLib,
+checked against a CDB or SQLite database of known weak passwords with some
+transformations, checked for length, checked for non-printable or
+non-ASCII characters that may be difficult to enter reproducibly, required
+to contain particular character classes, or any combination of these
+tests.
--- /dev/null
+You will also need Perl 5.010 or later and the DBI, DBD::SQLite, JSON,
+Perl6::Slurp, and Readonly modules (from CPAN) to generate man pages and
+bootstrap the test suite data from a Git checkout.
--- /dev/null
+By default, the Heimdal external password check function is installed as
+`/usr/local/bin/heimdal-strength`, and the plugin is installed as
+`/usr/local/lib/krb5/plugins/pwqual/strength.so`. You can change these
+paths with the `--prefix`, `--libdir`, and `--bindir` options to
+configure.
+
+By default, the embedded version of CrackLib will be used. To build with
+the system version of CrackLib, pass `--with-cracklib` to configure. You
+can optionally add a directory, giving the root directory where CrackLib
+was installed, or separately set the include and library path with
+`--with-cracklib-include` and `--with-cracklib-lib`.
+
+krb5-strength will automatically build with TinyCDB if it is found. To
+specify the installation path of TinyCDB, use `--with-tinycdb`. You can
+also separately set the include and library path with
+`--with-tinycdb-include` and `--with-tinycdb-lib`.
+
+Similarly, krb5-strength will automatically build with SQLite if it is
+found. To specify the installation path of SQLite, use `--with-sqlite`.
+You can also separately set the include and library path with
+`--with-sqlite-include` and `--with-sqlite-lib`.
--- /dev/null
+After installing this software, see the man pages for krb5-strength,
+heimdal-strength, and heimdal-history for configuration information.
--- /dev/null
+Heimdal includes a capability to plug in external password quality checks
+and comes with an example that checks passwords against CrackLib.
+However, in testing at Stanford, we found that CrackLib with its default
+transform rules does not catch passwords that can be guessed using the
+same dictionary with other tools, such as Jack the Ripper. We then
+discovered other issues with CrackLib with longer passwords, such as some
+bad assumptions about how certain measures of complexity will scale, and
+wanted to impose other limitations that it didn't support.
+
+This plugin provides the ability to check password quality against the
+standard version of CrackLib, or against a modified version of CrackLib
+that only passes passwords that resist attacks from both Crack and Jack
+the Ripper using the same rule sets. It also supports doing simpler
+dictionary checks against a CDB database, which is fast with very large
+dictionaries, or a SQLite database, which can reject all passwords within
+edit distance one of a dictionary word. It can also impose other
+programmatic checks on passwords such as character class requirements.
+
+If you're just now starting with password checking, I recommend using the
+SQLite database with a large wordlist and minimum password lengths. We
+found this produced the best results with the least user frustration.
+
+For Heimdal, krb5-strength includes both a program usable as an external
+password quality check and a plugin that implements the dynamic module
+API. For MIT Kerberos (1.9 or later), it includes a plugin for the
+password quality (pwqual) plugin API.
+
+krb5-strength can be built with either the system CrackLib or with the
+modified version of CrackLib included in this package. Note, however,
+that if you're building against the system CrackLib, Heimdal includes in
+the distribution a strength-checking plugin and an external password check
+program that use the system CrackLib. With Heimdal, it would probably be
+easier to use that plugin or program than build this package unless you
+want the modified CrackLib, one of the other dictionary types, or the
+additional character class and length checks.
+
+For information about the changes to the CrackLib included in this
+toolkit, see `cracklib/HISTORY`. The primary changes are tighter rules,
+which are more aggressive at finding dictionary words with characters
+appended and prepended, which tighten the requirements for password
+entropy, and which add stricter rules for longer passwords. They are also
+minor changes to fix portability issues, remove some code that doesn't
+make sense in the kadmind context, and close a few security issues. The
+standard CrackLib distribution on at least some Linux distributions now
+supports an additional interface to configure its behavior, and
+krb5-strength should change in the future to use that interface and drop
+the embedded copy.
+
+krb5-strength also includes a password history implementation for Heimdal.
+This is separate from the password strength implementation but can be
+stacked with it so that both strength and history checks are performed.
+This history implementation is available only via the Heimdal external
+password quality interface. MIT Kerberos includes its own password
+history implementation.
--- /dev/null
+{
+ "name": "krb5-strength",
+ "version": "3.1",
+ "synopsis": "Kerberos password strength checking plugin",
+ "maintainer": "Russ Allbery <eagle@eyrie.org>",
+ "copyrights": [
+ {
+ "holder": "Russ Allbery <eagle@eyrie.org>",
+ "years": "2016",
+ },
+ {
+ "holder": "The Board of Trustees of the Leland Stanford Junior University",
+ "years": "2006-2007, 2009-2010, 2012-2014",
+ },
+ {
+ "holder": "Alec Muffett",
+ "years": "1993",
+ },
+ ],
+ "license": "Expat",
+ "build": {
+ "lancaster": true,
+ "autotools": true,
+ "automake": "1.11",
+ "autoconf": "2.64",
+ "type": "Autoconf",
+ "reduced_depends": true,
+ "kerberos": true,
+ },
+ "support": {
+ "email": "eagle@eyrie.org",
+ "github": "rra/krb5-strength",
+ "web": "https://www.eyrie.org/~eagle/software/krb5-strength/",
+ },
+ "vcs": {
+ "type": "Git",
+ "url": "https://git.eyrie.org/git/kerberos/krb5-strength.git",
+ "browse": "https://git.eyrie.org/?p=devel/krb5-strength.git",
+ "github": "rra/krb5-strength",
+ "openhub": "https://www.openhub.net/p/krb5-strength",
+ },
+ "distribution": {
+ "section": "kerberos",
+ "tarname": "krb5-strength",
+ "version": "krb5-strength",
+ },
+ "docs": {
+ "user": [
+ {
+ "name": "heimdal-history",
+ "title": "heimdal-history",
+ },
+ {
+ "name": "heimdal-strength",
+ "title": "heimdal-strength",
+ },
+ {
+ "name": "krb5-strength",
+ "title": "krb5-strength plugin",
+ },
+ {
+ "name": "krb5-strength-wordlist",
+ "title": "krb5-strength-wordlist",
+ },
+ ],
+ },
+}
--- /dev/null
+Developed by Derrick Brashear and Ken Hornstein of Sine Nomine Associates,
+on behalf of Stanford University.
+
+The embedded version of CrackLib (all files in the `cracklib`
+subdirectory) is covered by the Artistic license. See the file
+`cracklib/LICENCE` for more information. Combined derivative works that
+include this code, such as binaries built with the embedded CrackLib, will
+need to follow the terms of the Artistic license as well as the above
+license.
--- /dev/null
+For Heimdal, you may use either the external password quality check tool,
+installed as heimdal-strength, or the plugin as you choose. It has been
+tested with Heimdal 1.2.1 and later, but has not recently been tested with
+versions prior to 1.5.
+
+For MIT Kerberos, version 1.9 or higher is required for the password
+quality plugin interface. MIT Kerberos does not support an external
+password quality check tool directly, so you will need to install the
+plugin.
+
+You can optionally build against the system CrackLib library. Any version
+should be supported, but note that some versions, particularly older
+versions close to the original code, do things like printing diagnostics
+to stderr, calling exit, and otherwise not being well-behaved for use
+inside plugins or libraries. They also have known security
+vulnerabilities. If using a system CrackLib library, use version 2.8.22
+or later to avoid these problems.
+
+You can also optionally build against the TinyCDB library, which provides
+support for simpler and faster password checking against a CDB dictionary
+file, and the SQLite library (a version new enough to support the
+`sqlite3_open_v2` API; 3.7 should be more than sufficient), which provides
+support for checking whether passwords are within edit distance one of a
+dictionary word.
+
+For this module to be effective for either Heimdal or MIT Kerberos, you
+will also need to construct a dictionary. The `mkdict` and `packer`
+utilities to build a CrackLib dictionary from a word list are included in
+this toolkit but not installed by default. You can run them out of the
+`cracklib` directory after building. You can also use the utilities that
+come with the stock CrackLib package (often already packaged in a Linux
+distribution); the database format is compatible.
+
+For building a CDB or SQLite dictionary, use the provided
+`krb5-strength-wordlist` program. For CDB dictionries, the `cdb` utility
+must be on your `PATH`. For SQLite, the DBI and DBD::SQLite Perl modules
+are required. `krb5-strength-wordlist` requires Perl 5.006 or later.
+
+For a word list to use as source for the dictionary, you can use
+`/usr/share/dict/words` if it's available on your system, but it would be
+better to find a more comprehensive word list. Since word lists are
+bulky, often covered by murky copyrights, and easily locatable on the
+Internet with a modicum of searching, none are included in this toolkit.
+
+The password history program, heimdal-history, requires Perl 5.010 or
+later plus the following CPAN modules:
+
+* DB_File::Lock
+* Crypt::PBKDF2
+* Getopt::Long::Descriptive
+* IPC::Run
+* JSON
+* Readonly
+
+and their dependencies.
+
+To run the test suite, you will need Perl 5.010 or later and the
+dependencies of the `heimdal-history` program. The following additional
+Perl modules will also be used by the test suite if present:
+
+* Perl6::Slurp
+* Test::MinimumVersion
+* Test::Perl::Critic
+* Test::Pod
+* Test::Spelling
+* Test::Strict
+
+All are available on CPAN. Some tests will be skipped if the modules
+are not available.
projects / kerberos / krb5-strength.git / commitdiff