Sentinel Hardware Keys Developer's Guide - Customer Connection ...

Chapter 7 – Implementing Secure Licensing
Contents Glossary Index Troubleshooting
Call the SFNTDecrypt API function obtain the decrypted data. If the
decrypted data matches the plain data, the correct Sentinel Key is
assumed to be present.
It becomes impossible to replicate these results by skipping the Sentinel Key
because all the operations are performed in the hardware.
SFNTEncrypt and SFNTDecrypt Operations
You can use encryption to protect your application in many ways.
Encrypt the Query/Response Table
You should encrypt the query/response table, making it extremely difficult
to find and use the table by looking at the code. If you only decrypt challenges
as you use them, then the attacker never sees the table in a fully
decrypted form.
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