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<title>ftpasswd: tool for ProFTPD's AuthUserFile, AuthGroupFile, UserPassword </title>
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<h2><b><code>ftpasswd</code>: tool for ProFTPD's <code>AuthUserFile</code>, <code>AuthGroupFile</code>, <code>UserPassword</code></b></h2>
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<hr><br>
This program is used to create and manage files, correctly formatted, suitable
for use with ProFTPD's <a href="http://www.proftpd.org/docs/configuration.html#AuthUserFile"><code>AuthUserFile</code></a> and <a href="http://www.proftpd.org/docs/configuration.html#AuthGroupFile"><code>AuthGroupFile</code></a>
configuration directives. It can also generate password hashes for ProFTPD's
<a href="http://www.proftpd.org/docs/configuration.html#UserPassword"><code>UserPassword</code></a> directive.
<p>
The most current version of <code>ftpasswd</code> can be found at:
<pre>
<a href="http://www.castaglia.org/proftpd/">http://www.castaglia.org/proftpd/</a>
</pre>
<h2>Author</h2>
<p>
Please contact TJ Saunders <tj <i>at</i> castaglia.org> with any
questions, concerns, or suggestions regarding this program.
<p>
<hr><br>
<h2><a name="Usage">Usage</a></h2>
The following describes the common usage of the <code>ftpasswd</code> tool.
The options supported are described in more detail
<a href="#Options">later</a>.
<p>
This script is intended to replace the <code>genuser.pl</code> script that
is currently distributed with <code>proftpd</code>. That script can
generate DES-hashed passwords, suitable for use with the <a href="http://www.proftpd.org/docs/configuration.html#UserPassword"><code>UserPassword</code></a>
configuration directive, but it is not quite right for
<code>AuthUserFile</code>s. Another common mistake is to use the
<code>htpasswd</code> program from Apache to create files for
<code>proftpd</code>. Apache and ProFTPD both have the same
<code>AuthUserFile</code> and <code>AuthGroupFile</code> directives; the format
of the files used by each server is different.
<p>
<b>Creating Files</b><br>
The <code>ftpasswd</code> program can create and update files for both
<code>AuthUserFile</code> and <code>AuthGroupFile</code>. When it is used
for the first time, the program will create the necessary file. If that
file already exists, <code>ftpasswd</code> will update it with the new
information.
<p>
<code>ftpasswd</code> must first know what type of file to create. Use either
the <code>--passwd</code> option (for handling <code>AuthUserFile</code>s), or
the <code>--group</code> option (for handling <code>AuthGroupFile</code>s);
this is required.
<p>
When creating an <code>AuthUserFile</code>, the following options are also
required: <code>--name</code>, <code>--uid</code>, <code>--home</code>, and
<code>--shell</code>. This information is required by <code>proftpd</code> to
authenticate a user. The optional parameters for an <code>AuthUserFile</code>
include <code>--gid</code> (defaults to the given <code>--uid</code> argument
when not provided) and <code>--gecos</code> (not used by <code>proftpd</code>
at all). For example:
<pre>
ftpasswd --passwd --name=bob --uid=1001 --home=/home/bob --shell=/bin/false
</pre>
creates an account for user <code>bob</code>. To create a file with a name or
location other than the default (which, for <code>--passwd</code> mode is
<code>ftpd.passwd</code>), use the <code>--file</code> option. For example, to create the alternate password file in <code>/usr/local/etc/ftpd/passwd</code>:
<pre>
ftpasswd --passwd --file=/usr/local/etc/ftpd/passwd --name=bob --uid=1001 --home=/home/bob \
--shell=/bin/false
</pre>
<p>
For <code>AuthGroupFile</code>s, use <code>--group</code>:
<pre>
ftpasswd --group --name=<i>group-name</i> --gid=<i>group-id</i> --member=<i>user-member1</i> \
--member=<i>user-member2</i> ... --member=<i>user-memberN</i>
</pre>
<p>
The most common change to these files is made to <code>AuthUserFile</code>s, to
change a user's password. The <code>--change-password</code> option was
provided just for this scenario:
<pre>
ftpasswd --passwd --name=<i>user</i> --change-password
</pre>
<p>
<b>Creating Hashes</b><br>
A less common need is to generate a password hash for some user, to be used
in a <code>UserPassword</code> directive in the <code>proftpd.conf</code>.
One could generate a file using <code>--passwd</code> and then extract the
password hash from the file. Easier, though, is to use <code>ftpasswd</code>'s
<code>--hash</code> option:
<pre>
ftpasswd --hash
</pre>
The password will either be prompted for, or it can be given on standard in
using <code>--stdin</code>.
<p>
<b>Automated Use</b><br>
The <code>ftpasswd</code> provides a useful command-line interface to
interacting with the authentication files. Many sites would like to be able
to remotely manipulate these files, just as <code>ftpasswd</code> does, only
using a web-based mechanism, perhaps even providing a page to users to change
their passwords, instead of requiring use of a shell. Wrapping a shell
or Perl script around <code>ftpasswd</code> is the logical solution.
<p>
To aid such automated wrapper scripts, <code>ftpasswd</code> has two features:
its return value, and a specific option. The program returns 0 if the
requested change was successful, and 1 if there was an error (no such
user/group, password matched system password and the
<code>--not-system-password</code> option was used, etc.). The specific
option is <code>--stdin</code>: this allows scripts to provide a password to
<code>ftpasswd</code> without prompting for a password. For example:
<pre>
echo <i>passwd-variable</i> | ftpasswd <i>opts</i> --stdin
</pre>
Note that the <code>--stdin</code> option does <b>not</b> allow passwords to
be passed to the script on the command line, but on <code>stdin</code>. This
is done as a security measure: the standard Unix <code>ps</code> command can
be used to show all the processes running on a system <i>including their
command line parameters</i>. This means that any user could use
<code>ps</code> to watch passwords given to <code>ftpasswd</code>, if those
passwords were to be passed on the command line. Some operating systems
(<i>e.g.</i> FreeBSD) allow the sysadmin to prevent users from seeing all
processes in this manner; consult your operating system documentation for
more information.
<p>
There are other issues that arise when using <code>AuthUserFile</code>s.
This <a href="http://www.castaglia.org/proftpd/doc/contrib/ProFTPD-mini-HOWTO-AuthFiles.html">document</a> discusses these issues in greater detail.
<p>
<hr><br>
<h2><a name="Options">Options</a></h2>
The following is the output from running <code>ftpasswd --help</code>:
<pre>
usage: ftpasswd [--help] [--hash|--group|--passwd]
REQUIRED: --passwd, --group, or --hash. These specify whether ftpasswd is to
operate on a passwd(5) format file, on a group(5) format file, or simply
to generate a password hash, respectively.
If used with --passwd, ftpasswd creates a file in the passwd(5) format,
suitable for use with proftpd's AuthUserFile configuration directive.
You will be prompted for the password to use of the user, which will be
encrypted, and written out as the encrypted string. New entries are
appended to the file by default.
By default, using --passwd will write output to "./ftpd.passwd".
Error exit values:
To make it easier for wrapper scripts to interact with ftpasswd, ftpasswd
will exit with the following error values for the reasons described:
1 no such user
2 password matches current password
4 password matches system password
8 relative path given for home directory
Options:
--file Write output to specified file, rather than "./ftpd.passwd"
-F If the file to be used already exists, delete it and write a
--force new one. By default, new entries will be appended to the file.
--gecos Descriptive string for the given user (usually the user's
full name).
--gid Primary group ID for this user (optional, will default to
given --uid value if absent)
-h Displays this message
--help
--home Home directory for the user (required)
--des Use the DES algorithm for encrypting passwords. The default
is the MD5 algorithm.
--md5 Use the MD5 algorithm for encrypting passwords. This is the
default.
--name Name of the user account (required). If the name does not
exist in the specified output-file, an entry will be created
for her. Otherwise, the given fields will be updated.
--shell Shell for the user (required). Recommended: /bin/false
--uid Numerical user ID (required)
--change-password
Update only the password field for a user. This option
requires that the --name and --passwd options be used, but no
others. This also double-checks the given password against
the user's current password in the existing passwd file, and
requests that a new password be given if the entered password
is the same as the current password.
--delete-user
Remove the entry for the given user name from the file.
--not-previous-password
Double-checks the given password against the previous password
for the user, and requests that a new password be given if
the entered password is the same as the previous password.
--not-system-password
Double-checks the given password against the system password
for the user, and requests that a new password be given if
the entered password is the same as the system password. This
helps to enforce different passwords for different types of
access.
--stdin
Read the password directly from standard in rather than
prompting for it. This is useful for writing scripts that
automate use of ftpasswd.
--use-cracklib
Causes ftpasswd to use Alec Muffet's cracklib routines in
order to determine and prevent the use of bad or weak
passwords. The optional path to this option specifies
the path to the dictionary files to use -- default path
is "/usr/lib/cracklib_dict". This requires the Perl
Crypt::Cracklib module to be installed on your system.
--version
Displays the version of ftpasswd.
If used with --group, ftpasswd creates a file in the group(5) format,
suitable for use with proftpd's AuthGroupFile configuration directive.
By default, using --group will write output to "./ftpd.group".
Options:
--delete-group
Remove the entry for the given group name from the file.
--enable-group-passwd
Prompt for a group password. This is disabled by default,
as group passwords are not usually a good idea at all.
--file Write output to specified file, rather than "./ftpd.group"
-F If the file be used already exists, delete it and write a new
--force one. By default, new entries will be appended to the file.
--gid Numerical group ID (required)
-h
--help Displays this message
-m
--member User to be a member of the group. This argument may be used
multiple times to specify the full list of users to be members
of this group.
--des Use the DES algorithm for encrypting passwords. The default
is the MD5 algorithm.
--md5 Use the MD5 algorithm for encrypting passwords. This is the
default.
--name Name of the group (required). If the name does not exist in
the specified output-file, an entry will be created for them.
Otherwise, the given fields will be updated.
--stdin
Read the password directly from standard in rather than
prompting for it. This is useful for writing scripts that
automate use of ftpasswd.
--use-cracklib
Causes ftpasswd to use Alec Muffet's cracklib routines in
order to determine and prevent the use of bad or weak
passwords. The optional path to this option specifies
the path to the dictionary files to use -- default path
is "/usr/lib/cracklib_dict". This requires the Perl
Crypt::Cracklib module to be installed on your system.
--version
Displays the version of ftpasswd.
If used with --hash, ftpasswd generates a hash of a password, as would
appear in an AuthUserFile. The hash is written to standard out.
This hash is suitable for use with proftpd's UserPassword directive.
Options:
--des Use the DES algorithm for encrypting passwords. The default
is the MD5 algorithm.
--md5 Use the MD5 algorithm for encrypting passwords. This is the
default.
--stdin
Read the password directly from standard in rather than
prompting for it. This is useful for writing scripts that
automate use of ftpasswd.
--use-cracklib
Causes ftpasswd to use Alec Muffet's cracklib routines in
order to determine and prevent the use of bad or weak
passwords. The optional path to this option specifies
the path to the dictionary files to use -- default path
is "/usr/lib/cracklib_dict". This requires the Perl
Crypt::Cracklib module to be installed on your system.
</pre>
<p>
<hr><br>
Author: <i>$Author: castaglia $</i><br>
Last Updated: <i>$Date: 2004/11/03 19:37:44 $</i><br>
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<font size=2><b><i>
© Copyright 2000-2002 TJ Saunders<br>
All Rights Reserved<br>
</i></b></font>
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