The HTAccess Authentication/Password
Protection tutorial covers web-based user authentication using a .htaccess file. Web-based authentication denies web access to visitors who do not give a valid username and password. This password protection feature allows webmasters to restrict access to certain directories. The usernames and encrypted passwords are kept in a webmaster-maintained file. T

Difficulty: Easy to Medium

You will need the following basic skills:

• Ability to telnet and log in to your virtual domain
• Ability to use a text editor (such as joe or pico on our system or notepad on yours)
• Working knowledge of paths and basic filesystem navigation (cd, mkdir, etc.)

Here we go!

The following is an example use of the .htaccess file. Let's assume that it resides at /mnt/web/guide/somewhere/somepath/.htaccess

AuthUserFile /mnt/web/guide/somewhere/somepath/.htpasswd
AuthGroupFile /dev/null
AuthName "Somewhere.com's Secret Section"
AuthType Basic

<Limit GET POST>
require valid-user
</Limit>

The .htacce ss file affects the directory in which it is placed, so in this example, any visitor requesting <URL:http://somewhere.com/somepath/> would be presented with an authentication request.

The .htaccess file also affects directories recursively below it. Therefore, requesting <URL:http://somewhere.com/somepath/evenmore/> would yield the same authentication request unless ~/somepath/evenmore had a .htaccess file of its own.

The first line, starting with AuthUserFile, tells the webserver where to find your username/password file. We'll create that file in a minute. For now, change the AuthUserFile line as necessary for your use.

Notice that the AuthName in the example, "Somewhere.com's Secret Section," is used in the authentication request. Although the quotes are not neccesary in some older versions of Apache, we recommend using them to avoid future incompatibility.

Using your favorite text editor, create a file similar to the example, replacing AuthUserFile and AuthName with values for your situation. Be sure to name the file .htaccess. (You can create the file locally and FTP it up to the server or you can log into the server via telnet and create the file using pico or joe)

Now that we understand the basic .htaccess model, how can we specify who is allowed? We'll create an .htpasswd file named in the AuthUserFile line above.

To create an .htpasswd file, login to the server via telnet go to the directory you specified in AuthUserFile. In the example, this is /mnt/web/guide/somewhere/somepath. Then use the htpasswd program with the -c switch to create your .htpasswd in the current directory.

Type htpasswd -c .htpasswd username to create the file and add "username" as the first user. The program will prompt you for a password, then verify by asking again. You will not see the password when entering it here:

wwwX:/mnt/web/guide/YOURDOMAINNAME/somepath#

htpasswd -c .htpasswd username

Adding password for username.

New password:

password

Re-type new password:

password

To add more users in the future, use the same command without the -c switch: htpasswd .htpasswd bob will add username "bob" to your .htpasswd file.

To delete users, open the .htpasswd file in a text editor and delete the appropriate lines:

username:v3l0KWx6v8mQM

bob:x4DtaLTqsElC2

To learn more about htaccess's capabilities, check out NCSA's site.