Enterprise Library Test Guide - Willy .Net

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Enterprise Library Test Guide
Test Case
The test case created an instance of the DpapiCryptographer class and passed the
DataProtectionScope mode as LocalMachine. It called the DpapiCryptographer.
Encrypt method with null entropy. It then checked to verify that the data was encrypted.
Problem
The Encrypt method checked to see whether the DataProtectionScope enumeration
was set to LocalMachine. If it was, and there was no entropy, the method threw an
exception. This is incorrect. Entropy is not a requirement for local stores in highly
trusted computers that are used for server-side applications. The DataProtection-
Scope.LocalMachine setting with no entropy is actually valid. The following code
caused the problem.
public byte[] Encrypt(byte[] plaintext)
{
if (DataProtectionScope.LocalMachine == storeScope)
{
throw new InvalidOperationException(Resources.DpapiMustHaveEntropyForMachineMode);
}
return Encrypt(plaintext, null);
}
Solution
To solve the problem, the code that checked for the LocalMachine setting when there
was no entropy was removed. The following is the modified code.
public byte[] Encrypt(byte[] plaintext)
{
}
return Encrypt(plaintext, null);
Verification
Running the modified code verified that the Encrypt method no longer threw an
exception.
Testing the Data Access Application Block
The test case determined whether the Data Access Application Block could read configuration
information from a configuration source other than a file. For the test, the
configuration source was an in-memory dictionary and the configuration information
was a connection string.