htpasswd manpage

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HTPASSWD(1)			   htpasswd			   HTPASSWD(1)

       htpasswd - Manage user files for basic authentication

       htpasswd [ -c ] [ -i ] [ -m | -B | -2 | -5 | -d | -s | -p ] [ -r rounds
       ] [ -C cost ] [ -D ] [ -v ] passwdfile username

       htpasswd -b [ -c ] [ -m | -B | -2 | -5 | -d | -s | -p ] [ -r rounds ] [
       -C cost ] [ -D ] [ -v ] passwdfile username password

       htpasswd -n [ -i ] [ -m | -B | -2 | -5 | -d | -s | -p ] [ -r rounds ] [
       -C cost ] username

       htpasswd -nb [ -m | -B | -2 | -5 | -d | -s | -p ] [ -r rounds  ]	 [  -C
       cost ] username password

       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
       hash and display password information for use in other  types  of  data
       stores, though. To use a DBM database see dbmmanage or htdbm.

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

       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/.

       -b     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 com-
	      mand line. For script use see the -i option. Available in	 2.4.4
	      and later.

       -i     Read  the	 password  from stdin without verification (for script

       -c     Create the passwdfile.  If  passwdfile  already  exists,	it  is
	      rewritten and truncated. This option cannot be combined with the
	      -n option.

       -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  com-
	      bined with the -c option.

       -m     Use  MD5	hashing for passwords. This is the default (since ver-
	      sion 2.2.18).

       -2     Use SHA-256 crypt() based hashes for  passwords.	This  is  sup-
	      ported on most Unix platforms.

       -5     Use  SHA-512  crypt()  based  hashes for passwords. This is sup-
	      ported on most Unix platforms.

       -B     Use bcrypt hashing for passwords. This is	 currently  considered
	      to be very secure.

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

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

       -d     Use  crypt() hashing 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.

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

       -p     Use  plaintext  passwords. Though htpasswd will support creation
	      on all platforms, the httpd daemon will only accept  plain  text
	      passwords on Windows and Netware.

       -D     Delete  user.  If	 the username exists in the specified htpasswd
	      file, it will be deleted.

       -v     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 later.

	      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 hashed and stored in the file. Only
	      used with the -b flag.

       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 opera-
       tion 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.

	     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 hashed 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  mes-
       sage 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 fetch-
       able 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
       plaintext 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-1  hashing  format does not use salting: for a given password,
       there is only one hashed 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-1 and crypt() formats are insecure by today's standards.

       The SHA-2-based crypt() formats (SHA-256 and SHA-512) are supported  on
       most   modern   Unix   systems,	 and   follow	the  specification  at

       On the Windows platform, passwords hashed with htpasswd are limited  to
       no  more	 than 255 characters in length. Longer passwords will be trun-
       cated to 255 characters.

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

       Usernames are limited to 255 bytes and may not include the character :.

       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 and later.

Apache HTTP Server		  2024-04-02			   HTPASSWD(1)