iTP Secure WebServer System Administrator's Guide (Version 7.0)

Configuring for Secure Transport
iTP Secure WebServer System Administrator’s Guide—523346-012
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Using SSL and PCT Environment Variables in CGI
Programs
RegionSet goodusers $goodusers
Region /* {
RequireSecureTransport -auth $goodusers
}
This command allows access only to clients who have presented a certificate by using
one of the DNs specified in goodusers.
Using SSL and PCT Environment Variables in CGI Programs
You can use SSL and PCT environment variables to access information about
individual requests from within CGI programs.
SSL environment variables are accessible from CGI programs. The method for
accessing these variables depends on the programming language being used. For a
list of the SSL and PCT environment variables and for information about how to use
them programmatically, see Section 8, Using Common Gateway Interface (CGI)
Programs.
Controlling Encryption and Integrity Checking
The iTP Secure WebServer allows the Web client and server to negotiate which
encryption algorithm will be used. The encryption algorithm is called a cipher. The
choice of cipher controls both the encryption and integrity checking required between
client and server.
Encryption protects the privacy of a message in transit, while integrity checking
provides proof that a message has not been altered during transit.
Using Ciphers With the AcceptSecureTransport Directive
The iTP Secure WebServer allows you to specify the ciphers that you want the
WebServer to support. Specifying a particular cipher mode ensures the maximum
security for each connection.
Encryption and integrity checking are controlled through the AcceptSecureTransport
directive’s -ciphers argument. For details about the syntax and use of the -ciphers
argument, see AcceptSecureTransport
on page A-6.
In general, your selection of the ciphers depends on your use of the iTP Secure
WebServer. For example, for financial transactions and private personal data, the
cipher Triple DES increases the amount of security. For basic level privacy, RC4
generally provides enough security while optimizing for speed.
Hashing Ciphers Used by iTP Secure WebServer Ciphers
The ciphers for secure transport ports within the iTP Secure WebServer can use two
different hashing algorithms. The first, called MD5, has been in wide use for many
years in various Internet applications. The other, called Secure Hash Algorithm