htpasswd

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  ht-
       passwd  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 ar-
              gument (usually the first one) is omitted. It cannot be combined
              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 17).

       -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 re-
       turns 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 in-
       teractively and the verification entry didn't match, 4 if its operation
       was interrupted, 5 if a value is too long  (username,  filename,  pass-
       word,  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 ex-
       cept 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  un-
       encrypted 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 :.

       The  cost  of computing a bcrypt password hash value increases with the
       number of rounds specified by the -C option. The apr-util  library  en-
       forces a maximum number of rounds of 17 in version 1.6.0 and later.

Apache HTTP Server                2019-08-09                       HTPASSWD(1)