7
This directive enables secure checksum generation along with %URI.Munge.
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It should be set to a secure key that is not shared with anyone else.
9
The checksum can be placed in the URI using %t. Use of this checksum
10
affords an additional level of protection by allowing a redirector
11
to check if a URI has passed through HTML Purifier with this line:
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<pre>$checksum === sha1($secret_key . ':' . $url)</pre>
17
If the output is TRUE, the redirector script should accept the URI.
21
Please note that it would still be possible for an attacker to procure
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secure hashes en-mass by abusing your website's Preview feature or the
23
like, but this service affords an additional level of protection
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that should be combined with website blacklisting.
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Remember this has no effect if %URI.Munge is not on.
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--# vim: et sw=4 sts=4