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| 10.7 Controlled Access Applications |
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Often it's desirable to control access to an application, due
to sensitive data. Or to split access across multiple users.
Two fundamental rules should always be kept in mind when
developing protected applications:
- Always assume your web server can be broken into.
- Never leave any sensitive data un-encrypted.
You can take every measure possible to properly use a
secure-http server, operating system security, and proper Texis
database permissions and still there might be some unknown breach
point that can threaten the security of your site. If you always
assume the worst can happen when you are writing code then you are
less likely to be vulnerable to a hacker.
That being said, let's look at an example of how to secure
a script. A typical application requires the following:
- Multiple users
- Secret password per user
- Multiple permission levels
In addition to verifying the user, we can use the user name to
identify the user throughout the application.
A given user may have different permission levels as well.
Ordinary users can only search the site's data, for example,
but some other users are allowed to upload or insert data.
Still other users are administrators, allowed to create and
delete users outright.
Our example security
script implements this scheme
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