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 <manualpage metafile="htpasswd.xml.meta">
 <parentdocument href="./">Programs</parentdocument>

 <title>htpasswd - Manage user files for basic authentication</title>

 <summary>
     <p><code>htpasswd</code> is used to create and update the flat-files used to
     store usernames and password for basic authentication of HTTP users. If
     <code>htpasswd</code> cannot access a file, such as not being able to write
     to the output file or not being able to read the file in order to update it,
     it returns an error status and makes no changes.</p>

     <p>Resources available from the Apache HTTP server can be restricted to
     just the users listed in the files created by <code>htpasswd</code>. This
     program can only manage usernames and passwords stored in a flat-file. It
     can hash and display password information for use in other types of data
     stores, though. To use a DBM database see <program>dbmmanage</program> or
     <program>htdbm</program>.</p>

     <p><code>htpasswd</code> hashes passwords using either bcrypt, a
     version of MD5 modified for Apache, SHA-1, or the system's
     <code>crypt()</code> routine. SHA-2-based hashes (SHA-256 and
     SHA-512) are supported for <code>crypt()</code>.  Files managed by
     <code>htpasswd</code> may contain a mixture of different encoding
     types of passwords; some user records may have bcrypt or
     MD5-hashed passwords while others in the same file may have
     passwords hashed with <code>crypt()</code>.</p>

     <p>This manual page only lists the command line arguments. For details of
     the directives necessary to configure user authentication in
     <program>httpd</program> see the Apache manual, which is part of the
     Apache distribution or can be found at <a href="http://httpd.apache.org"
     >http://httpd.apache.org/</a>.</p>
 </summary>
 <seealso><program>httpd</program></seealso>
 <seealso><program>htdbm</program></seealso>
 <seealso>The scripts in support/SHA1 which come with the
 distribution.</seealso>

 <section id="synopsis"><title>Synopsis</title>
     <p><code><strong>htpasswd</strong>
     [ -<strong>c</strong> ]
     [ -<strong>i</strong> ]
     [ -<strong>m</strong> |
       -<strong>B</strong> |
       -<strong>2</strong> |
       -<strong>5</strong> |
       -<strong>d</strong> |
       -<strong>s</strong> |
       -<strong>p</strong> ]
     [ -<strong>r</strong> <var>rounds</var> ]
     [ -<strong>C</strong> <var>cost</var> ]
     [ -<strong>D</strong> ]
     [ -<strong>v</strong> ]  <var>passwdfile</var> <var>username</var></code></p>

     <p><code><strong>htpasswd</strong> -<strong>b</strong>
     [ -<strong>c</strong> ]
     [ -<strong>m</strong> |
       -<strong>B</strong> |
       -<strong>2</strong> |
       -<strong>5</strong> |
       -<strong>d</strong> |
       -<strong>s</strong> |
       -<strong>p</strong> ]
     [ -<strong>r</strong> <var>rounds</var> ]
     [ -<strong>C</strong> <var>cost</var> ]
     [ -<strong>D</strong> ]
     [ -<strong>v</strong> ]  <var>passwdfile</var> <var>username</var>
     <var>password</var></code></p>

     <p><code><strong>htpasswd</strong> -<strong>n</strong>
     [ -<strong>i</strong> ]
     [ -<strong>m</strong> |
       -<strong>B</strong> |
       -<strong>2</strong> |
       -<strong>5</strong> |
       -<strong>d</strong> |
       -<strong>s</strong> |
       -<strong>p</strong> ]
     [ -<strong>r</strong> <var>rounds</var> ]
     [ -<strong>C</strong> <var>cost</var> ] <var>username</var></code></p>

     <p><code><strong>htpasswd</strong> -<strong>nb</strong>
     [ -<strong>m</strong> |
       -<strong>B</strong> |
       -<strong>2</strong> |
       -<strong>5</strong> |
       -<strong>d</strong> |
       -<strong>s</strong> |
       -<strong>p</strong> ]
     [ -<strong>r</strong> <var>rounds</var> ]
     [ -<strong>C</strong> <var>cost</var> ] <var>username</var>
     <var>password</var></code></p>
 </section>

 <section id="options"><title>Options</title>
     <dl>
     <dt><code>-b</code></dt>
     <dd>Use batch mode; <em>i.e.</em>, get the password from the command line
     rather than prompting for it. This option should be used with extreme care,
     since <strong>the password is clearly visible</strong> on the command
     line. For script use see the <code>-i</code> option.<br />
     Available in 2.4.4 and later.</dd>

     <dt><code>-i</code></dt>
     <dd>Read the password from stdin without verification (for script usage).</dd>

     <dt><code>-c</code></dt>
     <dd>Create the <var>passwdfile</var>. If <var>passwdfile</var> already
     exists, it is rewritten and truncated. This option cannot be combined with
     the <code>-n</code> option.</dd>

     <dt><code>-n</code></dt>
     <dd>Display the results on standard output rather than updating a file.
     This is useful for generating password records acceptable to Apache for
     inclusion in non-text data stores. This option changes the syntax of the
     command line, since the <var>passwdfile</var> argument (usually the first
     one) is omitted. It cannot be combined with the <code>-c</code> option.</dd>

     <dt><code>-m</code></dt>
     <dd>Use MD5 hashing for passwords. This is the default (since version
     2.2.18).</dd>

     <dt><code>-2</code></dt>
     <dd>Use SHA-256 <code>crypt()</code> based hashes for passwords.  This is
     supported on most Unix platforms.</dd>

     <dt><code>-5</code></dt>
     <dd>Use SHA-512 <code>crypt()</code> based hashes for passwords.  This is
     supported on most Unix platforms.</dd>

     <dt><code>-B</code></dt>
     <dd>Use bcrypt hashing for passwords. This is currently considered to
     be very secure.</dd>

     <dt><code>-C</code></dt>
     <dd>This flag is only allowed in combination with <code>-B</code> (bcrypt
     hashing). It sets the computing time used for the bcrypt algorithm
     (higher is more secure but slower, default: 5, valid: 4 to 17).</dd>

     <dt><code>-r</code></dt>
     <dd>This flag is only allowed in combination with <code>-2</code>
     or <code>-5</code>. It sets the number of hash rounds used for the
     SHA-2 algorithms (higher is more secure but slower; the default is
     5,000).</dd>

     <dt><code>-d</code></dt>
     <dd>Use <code>crypt()</code> hashing for passwords. This is not
     supported by the <program>httpd</program> server on Windows and
     Netware. This algorithm limits the password length to 8 characters.
     This algorithm is <strong>insecure</strong> by today's standards.
     It used to be the default algorithm until version 2.2.17.</dd>

     <dt><code>-s</code></dt>
     <dd>Use SHA-1 (160-bit) hashing for passwords. Facilitates migration
     from/to Netscape servers using the LDAP Directory Interchange
     Format (ldif).  This algorithm is <strong>insecure</strong> by
     today's standards.</dd>

     <dt><code>-p</code></dt>
     <dd>Use plaintext passwords. Though <code>htpasswd</code> will support
     creation on all platforms, the <program>httpd</program> daemon will
     only accept plain text passwords on Windows and Netware.</dd>

     <dt><code>-D</code></dt>
     <dd>Delete user. If the username exists in the specified htpasswd file, it
     will be deleted.</dd>

     <dt><code>-v</code></dt>
     <dd>Verify password. Verify that the given password matches the password
     of the user stored in the specified htpasswd file.<br />
     Available in 2.4.5 and later.</dd>

     <dt><code><var>passwdfile</var></code></dt>
     <dd>Name of the file to contain the user name and password. If
     <code>-c</code> is given, this file is created if it does not already exist,
     or rewritten and truncated if it does exist.</dd>

     <dt><code><var>username</var></code></dt>
     <dd>The username to create or update in <var>passwdfile</var>. If
     <var>username</var> does not exist in this file, an entry is added. If it
     does exist, the password is changed.</dd>

     <dt><code><var>password</var></code></dt>
     <dd>The plaintext password to be hashed and stored  in the file. Only
     used with the <code>-b</code> flag.</dd>
     </dl>
 </section>

 <section id="exit"><title>Exit Status</title>
     <p><code>htpasswd</code> returns a zero status ("true") if the username and
     password have been successfully added or updated in the
     <var>passwdfile</var>. <code>htpasswd</code> returns <code>1</code> if it
     encounters some problem accessing files, <code>2</code> if there was a
     syntax problem with the command line, <code>3</code> if the password was
     entered interactively and the verification entry didn't match,
     <code>4</code> if its operation was interrupted, <code>5</code> if a value
     is too long (username, filename, password, or final computed record),
     <code>6</code> if the username contains illegal characters (see the
     <a href="#restrictions">Restrictions section</a>), and <code>7</code>
     if the file is not a valid password file.</p>
 </section>

 <section id="examples"><title>Examples</title>
     <example>
       htpasswd /usr/local/etc/apache/.htpasswd-users jsmith
     </example>

     <p>Adds or modifies the password for user <code>jsmith</code>. The user
     is prompted for the password. The password will be hashed using the
     modified Apache MD5 algorithm. If the file does not exist,
     <code>htpasswd</code> will do nothing except return an error.</p>

     <example>
       htpasswd -c /home/doe/public_html/.htpasswd jane
     </example>

     <p>Creates a new file and stores a record in it for user <code>jane</code>.
     The user is prompted for the password. If the file exists and cannot be
     read, or cannot be written, it is not altered and <code>htpasswd</code>
     will display a message and return an error status.</p>

     <example>
       htpasswd -db /usr/web/.htpasswd-all jones Pwd4Steve
     </example>

     <p>Encrypts the password from the command line (<code>Pwd4Steve</code>)
     using the <code>crypt()</code> algorithm, and stores it in the specified
     file.</p>
 </section>

 <section id="security"><title>Security Considerations</title>
     <p>Web password files such as those managed by <code>htpasswd</code> should
     <em>not</em> be within the Web server's URI space -- that is, they should
     not be fetchable with a browser.</p>

     <p>This program is not safe as a setuid executable. Do <em>not</em> make it
     setuid.</p>

     <p>The use of the <code>-b</code> option is discouraged, since when it is
     used the plaintext password appears on the command line.</p>

     <p>When using the <code>crypt()</code> algorithm, note that only the first
     8 characters of the password are used  to form the password. If the supplied
     password is longer, the extra characters will be silently discarded.</p>

     <p>The SHA-1 hashing format does not use salting: for a given
     password, there is only one hashed representation. The
     <code>crypt()</code> and MD5 formats permute the representation by
     prepending a random salt string, to make dictionary attacks
     against the passwords more difficult.</p>

     <p>The SHA-1 and <code>crypt()</code> formats are insecure by
     today's standards.</p>

     <p>The SHA-2-based <code>crypt()</code> formats (SHA-256 and
     SHA-512) are supported on most modern Unix systems, and follow the
     specification at <a
     href="https://www.akkadia.org/drepper/SHA-crypt.txt">https://www.akkadia.org/drepper/SHA-crypt.txt</a>.</p>

 </section>

 <section id="restrictions"><title>Restrictions</title>
     <p>On the Windows platform, passwords hashed with
     <code>htpasswd</code> are limited to no more than <code>255</code>
     characters in length. Longer passwords will be truncated to 255
     characters.</p>

     <p>The MD5 algorithm used by <code>htpasswd</code> is specific to the Apache
     software; passwords hashed using it will not be usable with other Web
     servers.</p>

     <p>Usernames are limited to <code>255</code> bytes and may not include the
     character <code>:</code>.</p>

     <p>The cost of computing a bcrypt password hash value increases
     with the number of rounds specified by the <code>-C</code> option.
     The <code>apr-util</code> library enforces a maximum number of
     rounds of 17 in version <code>1.6.0</code> and later.</p>
 </section>

 </manualpage>
	<?xml version='1.0' encoding='UTF-8' ?>
	<!DOCTYPE manualpage SYSTEM "../style/manualpage.dtd">
	<?xml-stylesheet type="text/xsl" href="../style/manual.en.xsl"?>
	<!-- $LastChangedRevision$ -->

	<!--
	Licensed to the Apache Software Foundation (ASF) under one or more
	contributor license agreements. See the NOTICE file distributed with
	this work for additional information regarding copyright ownership.
	The ASF licenses this file to You under the Apache License, Version 2.0
	(the "License"); you may not use this file except in compliance with
	the License. You may obtain a copy of the License at

	http://www.apache.org/licenses/LICENSE-2.0

	Unless required by applicable law or agreed to in writing, software
	distributed under the License is distributed on an "AS IS" BASIS,
	WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	See the License for the specific language governing permissions and
	limitations under the License.
	-->

	<manualpage metafile="htpasswd.xml.meta">
	<parentdocument href="./">Programs</parentdocument>

	<title>htpasswd - Manage user files for basic authentication</title>

	<summary>
	<p><code>htpasswd</code> is used to create and update the flat-files used to
	store usernames and password for basic authentication of HTTP users. If
	<code>htpasswd</code> cannot access a file, such as not being able to write
	to the output file or not being able to read the file in order to update it,
	it returns an error status and makes no changes.</p>

	<p>Resources available from the Apache HTTP server can be restricted to
	just the users listed in the files created by <code>htpasswd</code>. This
	program can only manage usernames and passwords stored in a flat-file. It
	can hash and display password information for use in other types of data
	stores, though. To use a DBM database see <program>dbmmanage</program> or
	<program>htdbm</program>.</p>

	<p><code>htpasswd</code> hashes passwords using either bcrypt, a
	version of MD5 modified for Apache, SHA-1, or the system's
	<code>crypt()</code> routine. SHA-2-based hashes (SHA-256 and
	SHA-512) are supported for <code>crypt()</code>. Files managed by
	<code>htpasswd</code> may contain a mixture of different encoding
	types of passwords; some user records may have bcrypt or
	MD5-hashed passwords while others in the same file may have
	passwords hashed with <code>crypt()</code>.</p>

	<p>This manual page only lists the command line arguments. For details of
	the directives necessary to configure user authentication in
	<program>httpd</program> see the Apache manual, which is part of the
	Apache distribution or can be found at <a href="http://httpd.apache.org"
	>http://httpd.apache.org/</a>.</p>
	</summary>
	<seealso><program>httpd</program></seealso>
	<seealso><program>htdbm</program></seealso>
	<seealso>The scripts in support/SHA1 which come with the
	distribution.</seealso>

	<section id="synopsis"><title>Synopsis</title>
	<p><code><strong>htpasswd</strong>
	[ -<strong>c</strong> ]
	[ -<strong>i</strong> ]
	[ -<strong>m</strong> \|
	-<strong>B</strong> \|
	-<strong>2</strong> \|
	-<strong>5</strong> \|
	-<strong>d</strong> \|
	-<strong>s</strong> \|
	-<strong>p</strong> ]
	[ -<strong>r</strong> <var>rounds</var> ]
	[ -<strong>C</strong> <var>cost</var> ]
	[ -<strong>D</strong> ]
	[ -<strong>v</strong> ] <var>passwdfile</var> <var>username</var></code></p>

	<p><code><strong>htpasswd</strong> -<strong>b</strong>
	[ -<strong>c</strong> ]
	[ -<strong>m</strong> \|
	-<strong>B</strong> \|
	-<strong>2</strong> \|
	-<strong>5</strong> \|
	-<strong>d</strong> \|
	-<strong>s</strong> \|
	-<strong>p</strong> ]
	[ -<strong>r</strong> <var>rounds</var> ]
	[ -<strong>C</strong> <var>cost</var> ]
	[ -<strong>D</strong> ]
	[ -<strong>v</strong> ] <var>passwdfile</var> <var>username</var>
	<var>password</var></code></p>

	<p><code><strong>htpasswd</strong> -<strong>n</strong>
	[ -<strong>i</strong> ]
	[ -<strong>m</strong> \|
	-<strong>B</strong> \|
	-<strong>2</strong> \|
	-<strong>5</strong> \|
	-<strong>d</strong> \|
	-<strong>s</strong> \|
	-<strong>p</strong> ]
	[ -<strong>r</strong> <var>rounds</var> ]
	[ -<strong>C</strong> <var>cost</var> ] <var>username</var></code></p>

	<p><code><strong>htpasswd</strong> -<strong>nb</strong>
	[ -<strong>m</strong> \|
	-<strong>B</strong> \|
	-<strong>2</strong> \|
	-<strong>5</strong> \|
	-<strong>d</strong> \|
	-<strong>s</strong> \|
	-<strong>p</strong> ]
	[ -<strong>r</strong> <var>rounds</var> ]
	[ -<strong>C</strong> <var>cost</var> ] <var>username</var>
	<var>password</var></code></p>
	</section>

	<section id="options"><title>Options</title>
	<dl>
	<dt><code>-b</code></dt>
	<dd>Use batch mode; <em>i.e.</em>, get the password from the command line
	rather than prompting for it. This option should be used with extreme care,
	since <strong>the password is clearly visible</strong> on the command
	line. For script use see the <code>-i</code> option.<br />
	Available in 2.4.4 and later.</dd>

	<dt><code>-i</code></dt>
	<dd>Read the password from stdin without verification (for script usage).</dd>

	<dt><code>-c</code></dt>
	<dd>Create the <var>passwdfile</var>. If <var>passwdfile</var> already
	exists, it is rewritten and truncated. This option cannot be combined with
	the <code>-n</code> option.</dd>

	<dt><code>-n</code></dt>
	<dd>Display the results on standard output rather than updating a file.
	This is useful for generating password records acceptable to Apache for
	inclusion in non-text data stores. This option changes the syntax of the
	command line, since the <var>passwdfile</var> argument (usually the first
	one) is omitted. It cannot be combined with the <code>-c</code> option.</dd>

	<dt><code>-m</code></dt>
	<dd>Use MD5 hashing for passwords. This is the default (since version
	2.2.18).</dd>

	<dt><code>-2</code></dt>
	<dd>Use SHA-256 <code>crypt()</code> based hashes for passwords. This is
	supported on most Unix platforms.</dd>

	<dt><code>-5</code></dt>
	<dd>Use SHA-512 <code>crypt()</code> based hashes for passwords. This is
	supported on most Unix platforms.</dd>

	<dt><code>-B</code></dt>
	<dd>Use bcrypt hashing for passwords. This is currently considered to
	be very secure.</dd>

	<dt><code>-C</code></dt>
	<dd>This flag is only allowed in combination with <code>-B</code> (bcrypt
	hashing). It sets the computing time used for the bcrypt algorithm
	(higher is more secure but slower, default: 5, valid: 4 to 17).</dd>

	<dt><code>-r</code></dt>
	<dd>This flag is only allowed in combination with <code>-2</code>
	or <code>-5</code>. It sets the number of hash rounds used for the
	SHA-2 algorithms (higher is more secure but slower; the default is
	5,000).</dd>

	<dt><code>-d</code></dt>
	<dd>Use <code>crypt()</code> hashing for passwords. This is not
	supported by the <program>httpd</program> server on Windows and
	Netware. This algorithm limits the password length to 8 characters.
	This algorithm is <strong>insecure</strong> by today's standards.
	It used to be the default algorithm until version 2.2.17.</dd>

	<dt><code>-s</code></dt>
	<dd>Use SHA-1 (160-bit) hashing for passwords. Facilitates migration
	from/to Netscape servers using the LDAP Directory Interchange
	Format (ldif). This algorithm is <strong>insecure</strong> by
	today's standards.</dd>

	<dt><code>-p</code></dt>
	<dd>Use plaintext passwords. Though <code>htpasswd</code> will support
	creation on all platforms, the <program>httpd</program> daemon will
	only accept plain text passwords on Windows and Netware.</dd>

	<dt><code>-D</code></dt>
	<dd>Delete user. If the username exists in the specified htpasswd file, it
	will be deleted.</dd>

	<dt><code>-v</code></dt>
	<dd>Verify password. Verify that the given password matches the password
	of the user stored in the specified htpasswd file.<br />
	Available in 2.4.5 and later.</dd>

	<dt><code><var>passwdfile</var></code></dt>
	<dd>Name of the file to contain the user name and password. If
	<code>-c</code> is given, this file is created if it does not already exist,
	or rewritten and truncated if it does exist.</dd>

	<dt><code><var>username</var></code></dt>
	<dd>The username to create or update in <var>passwdfile</var>. If
	<var>username</var> does not exist in this file, an entry is added. If it
	does exist, the password is changed.</dd>

	<dt><code><var>password</var></code></dt>
	<dd>The plaintext password to be hashed and stored in the file. Only
	used with the <code>-b</code> flag.</dd>
	</dl>
	</section>

	<section id="exit"><title>Exit Status</title>
	<p><code>htpasswd</code> returns a zero status ("true") if the username and
	password have been successfully added or updated in the
	<var>passwdfile</var>. <code>htpasswd</code> returns <code>1</code> if it
	encounters some problem accessing files, <code>2</code> if there was a
	syntax problem with the command line, <code>3</code> if the password was
	entered interactively and the verification entry didn't match,
	<code>4</code> if its operation was interrupted, <code>5</code> if a value
	is too long (username, filename, password, or final computed record),
	<code>6</code> if the username contains illegal characters (see the
	<a href="#restrictions">Restrictions section</a>), and <code>7</code>
	if the file is not a valid password file.</p>
	</section>

	<section id="examples"><title>Examples</title>
	<example>
	htpasswd /usr/local/etc/apache/.htpasswd-users jsmith
	</example>

	<p>Adds or modifies the password for user <code>jsmith</code>. The user
	is prompted for the password. The password will be hashed using the
	modified Apache MD5 algorithm. If the file does not exist,
	<code>htpasswd</code> will do nothing except return an error.</p>

	<example>
	htpasswd -c /home/doe/public_html/.htpasswd jane
	</example>

	<p>Creates a new file and stores a record in it for user <code>jane</code>.
	The user is prompted for the password. If the file exists and cannot be
	read, or cannot be written, it is not altered and <code>htpasswd</code>
	will display a message and return an error status.</p>

	<example>
	htpasswd -db /usr/web/.htpasswd-all jones Pwd4Steve
	</example>

	<p>Encrypts the password from the command line (<code>Pwd4Steve</code>)
	using the <code>crypt()</code> algorithm, and stores it in the specified
	file.</p>
	</section>

	<section id="security"><title>Security Considerations</title>
	<p>Web password files such as those managed by <code>htpasswd</code> should
	<em>not</em> be within the Web server's URI space -- that is, they should
	not be fetchable with a browser.</p>

	<p>This program is not safe as a setuid executable. Do <em>not</em> make it
	setuid.</p>

	<p>The use of the <code>-b</code> option is discouraged, since when it is
	used the plaintext password appears on the command line.</p>

	<p>When using the <code>crypt()</code> algorithm, note that only the first
	8 characters of the password are used to form the password. If the supplied
	password is longer, the extra characters will be silently discarded.</p>

	<p>The SHA-1 hashing format does not use salting: for a given
	password, there is only one hashed representation. The
	<code>crypt()</code> and MD5 formats permute the representation by
	prepending a random salt string, to make dictionary attacks
	against the passwords more difficult.</p>

	<p>The SHA-1 and <code>crypt()</code> formats are insecure by
	today's standards.</p>

	<p>The SHA-2-based <code>crypt()</code> formats (SHA-256 and
	SHA-512) are supported on most modern Unix systems, and follow the
	specification at <a
	href="https://www.akkadia.org/drepper/SHA-crypt.txt">https://www.akkadia.org/drepper/SHA-crypt.txt</a>.</p>

	</section>

	<section id="restrictions"><title>Restrictions</title>
	<p>On the Windows platform, passwords hashed with
	<code>htpasswd</code> are limited to no more than <code>255</code>
	characters in length. Longer passwords will be truncated to 255
	characters.</p>

	<p>The MD5 algorithm used by <code>htpasswd</code> is specific to the Apache
	software; passwords hashed using it will not be usable with other Web
	servers.</p>

	<p>Usernames are limited to <code>255</code> bytes and may not include the
	character <code>:</code>.</p>

	<p>The cost of computing a bcrypt password hash value increases
	with the number of rounds specified by the <code>-C</code> option.
	The <code>apr-util</code> library enforces a maximum number of
	rounds of 17 in version <code>1.6.0</code> and later.</p>
	</section>

	</manualpage>