htpasswd - Manage user files for basic authentication
htpasswd [ -c ] [ -i ] [ -m | -B |
-d | -s | -p ] [ -C cost ] [ -D ] [
-v ] passwdfile username
htpasswd -b [ -c ] [ -m |
-B | -d | -s | -p ] [ -C cost ] [
-D ] [ -v ] passwdfile username
htpasswd -n [ -i ] [ -m |
-B | -d | -s | -p ] [ -C cost ]
htpasswd -nb [ -m | -B |
-d | -s | -p ] [ -C cost ]
htpasswd is used to create and update the flat-files used to store
usernames and password for basic authentication of HTTP users. If
htpasswd 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.
Resources available from the Apache HTTP server can be restricted
to just the users listed in the files created by htpasswd. 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 dbmmanage or htdbm.
htpasswd encrypts passwords using either bcrypt, a version
of MD5 modified for Apache, SHA1, or the system's crypt() routine.
Files managed by htpasswd 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
This manual page only lists the command line arguments. For
details of the directives necessary to configure user authentication in
httpd see the Apache manual, which is part of the Apache distribution or can
be found at http://httpd.apache.org/.
htpasswd returns a zero status ("true") if the username and
password have been successfully added or updated in the passwdfile.
htpasswd returns 1 if it encounters some problem accessing
files, 2 if there was a syntax problem with the command line, 3
if the password was entered interactively and the verification entry didn't
match, 4 if its operation was interrupted, 5 if a value is too
long (username, filename, password, or final computed record), 6 if the
username contains illegal characters (see the Restrictions section), and
7 if the file is not a valid password file.
- Use batch mode; i.e., get the password from the command line rather
than prompting for it. This option should be used with extreme care, since
the password is clearly visible on the command line. For script use
see the -i option. Available in 2.4.4 and later.
- Read the password from stdin without verification (for script usage).
- Create the passwdfile. If passwdfile already exists, it is
rewritten and truncated. This option cannot be combined with the -n
- 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 passwdfile argument (usually the first one)
is omitted. It cannot be combined with the -c option.
- Use MD5 encryption for passwords. This is the default (since version
- Use bcrypt encryption for passwords. This is currently considered to be
- This flag is only allowed in combination with -B (bcrypt
encryption). It sets the computing time used for the bcrypt algorithm
(higher is more secure but slower, default: 5, valid: 4 to 17).
- Use crypt() encryption for passwords. This is not supported by the
httpd server on Windows and Netware. This algorithm limits the password
length to 8 characters. This algorithm is insecure by today's
standards. It used to be the default algorithm until version 2.2.17.
- Use SHA encryption for passwords. Facilitates migration from/to Netscape
servers using the LDAP Directory Interchange Format (ldif). This algorithm
is insecure by today's standards.
- Use plaintext passwords. Though htpasswd will support creation on
all platforms, the httpd daemon will only accept plain text passwords on
Windows and Netware.
- Delete user. If the username exists in the specified htpasswd file, it
will be deleted.
- Verify password. Verify that the given password matches the password of
the user stored in the specified htpasswd file. Available in 2.4.5 and
- Name of the file to contain the user name and password. If -c is
given, this file is created if it does not already exist, or rewritten and
truncated if it does exist.
- The username to create or update in passwdfile. If username
does not exist in this file, an entry is added. If it does exist, the
password is changed.
- The plaintext password to be encrypted and stored in the file. Only used
with the -b flag.
htpasswd /usr/local/etc/apache/.htpasswd-users jsmith
Adds or modifies the password for user jsmith. The user is
prompted for the password. The password will be encrypted using the modified
Apache MD5 algorithm. If the file does not exist, htpasswd will do
nothing except return an error.
htpasswd -c /home/doe/public_html/.htpasswd jane
Creates a new file and stores a record in it for user jane.
The user is prompted for the password. If the file exists and cannot be
read, or cannot be written, it is not altered and htpasswd will
display a message and return an error status.
htpasswd -db /usr/web/.htpasswd-all jones Pwd4Steve
Encrypts the password from the command line (Pwd4Steve)
using the crypt() algorithm, and stores it in the specified file.
Web password files such as those managed by htpasswd should not be
within the Web server's URI space -- that is, they should not be fetchable
with a browser.
This program is not safe as a setuid executable. Do not
make it setuid.
The use of the -b option is discouraged, since when it is
used the unencrypted password appears on the command line.
When using the crypt() 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.
The SHA encryption format does not use salting: for a given
password, there is only one encrypted representation. The crypt() and
MD5 formats permute the representation by prepending a random salt string,
to make dictionary attacks against the passwords more difficult.
The SHA and crypt() formats are insecure by today's
On the Windows platform, passwords encrypted with htpasswd are limited to
no more than 255 characters in length. Longer passwords will be
truncated to 255 characters.
The MD5 algorithm used by htpasswd is specific to the
Apache software; passwords encrypted using it will not be usable with other
Usernames are limited to 255 bytes and may not include the
The cost of computing a bcrypt password hash value increases with
the number of rounds specified by the -C option. The apr-util
library enforces a maximum number of rounds of 17 in version 1.6.0