NAME¶
htpasswd - Manage user files for basic authentication
SYNOPSIS¶
htpasswd [ -
c ] [ -
m ] [ -
D ]
passwdfile
username
htpasswd -
b [ -
c ] [ -
m | -
d | -
p |
-
s ] [ -
D ]
passwdfile username password
htpasswd -
n [ -
m | -
d | -
s | -
p ]
username
htpasswd -
nb [ -
m | -
d | -
s | -
p ]
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.
htpasswd encrypts passwords using either a version of MD5 modified for Apache,
or the system's crypt() routine. Files managed by htpasswd may contain both
types of passwords; some user records may have 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 command
line.
- -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 combined with the -c option.
- -m
- Use MD5 encryption for passwords. This is the default.
- -d
- Use crypt() encryption for passwords. This is not supported
by the httpd server on Windows and Netware and TPF.
- -s
- Use SHA encryption for passwords. Facilitates migration
from/to Netscape servers using the LDAP Directory Interchange Format
(ldif).
- -p
- Use plaintext passwords. Though htpasswd will support
creation on all platforms, the httpd daemon will only accept plain text
passwords on Windows, Netware and TPF.
- -D
- Delete user. If the username exists in the specified
htpasswd file, it will be deleted.
- 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 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.
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 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.
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 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.
RESTRICTIONS¶
On the Windows and MPE platforms, 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 :.