<?xml version='1.0' encoding='UTF-8' ?>

<!DOCTYPE manualpage SYSTEM "/style/manualpage.dtd">

<?xml-stylesheet type="text/xsl" href="/style/manual.en.xsl"?>

<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 encrypt 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> encrypts passwords using either bcrypt,

a version of MD5 modified for Apache, SHA1, or the system's

<code>crypt()</code> routine. Files

managed by <code>htpasswd</code> may contain a mixture of different encoding

types of passwords; some

user records may have bcrypt or MD5-encrypted passwords while others in the

same file may have passwords encrypted 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>d</strong> |

-<strong>s</strong> |

-<strong>p</strong> ]

[ -<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>d</strong> |

-<strong>s</strong> |

-<strong>p</strong> ]

[ -<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>d</strong> |

-<strong>s</strong> |

-<strong>p</strong> ]

[ -<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>d</strong> |

-<strong>s</strong> |

-<strong>p</strong> ]

[ -<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 encryption for passwords. This is the default (since version

2.2.18).</dd>

<dt><code>-B</code></dt>

<dd>Use bcrypt encryption 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

encryption). It sets the computing time used for the bcrypt algorithm

(higher is more secure but slower, default: 5, valid: 4 to 31).</dd>

<dt><code>-d</code></dt>

<dd>Use <code>crypt()</code> encryption 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 encryption 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 encrypted 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 encrypted 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 unencrypted 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 encryption format does not use salting: for a given password,

there is only one encrypted 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 and <code>crypt()</code> formats are insecure by today's

standards.</p>

</section>

<section id="restrictions"><title>Restrictions</title>

<p>On the Windows platform, passwords encrypted 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 encrypted 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>

</section>

</manualpage>