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htpasswd manpage

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HTPASSWD(1)			   htpasswd			   HTPASSWD(1)



NAME
       htpasswd - Manage user files for basic authentication


SYNOPSIS
       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 password


       htpasswd -n [ -i ] [ -m | -B | -d | -s | -p ] [ -C cost ] username


       htpasswd -nb [ -m | -B | -d | -s | -p ] [ -C cost ] username password



SUMMARY
       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 modi-
       fied for Apache, SHA1, or the system's crypt() routine.	Files  managed
       by  htpasswd may contain a mixture of different encoding types of pass-
       words; some user records may have  bcrypt  or  MD5-encrypted  passwords
       while  others  in  the  same  file  may	have  passwords encrypted 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/.



OPTIONS
       -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
	      usage).

       -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	encryption  for	 passwords. This is the default (since
	      version 2.2.18).

       -B     Use bcrypt encryption for passwords. This is  currently  consid-
	      ered to be very secure.

       -C     This flag is only allowed in combination with -B (bcrypt encryp-
	      tion). It sets the computing time used for the bcrypt  algorithm
	      (higher is more secure but slower, default: 5, valid: 4 to 31).

       -d     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.

       -s     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.

       -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.

       passwdfile
	      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.

       username
	      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.

       password
	      The plaintext password to be encrypted and stored in  the	 file.
	      Only used with the -b flag.


EXIT STATUS
       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.


EXAMPLES
	     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  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.


SECURITY CONSIDERATIONS
       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
       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 standards.


RESTRICTIONS
       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 Web servers.


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




Apache HTTP Server		  2014-06-24			   HTPASSWD(1)