Platform SDK: Security Glossary

H

handle
A token used to identify or access an object, such as the handle to a cryptographic provider, certificate store, message, or key pair.
hash
A fixed-size result obtained by applying a mathematical function (the hashing algorithm) to an arbitrary amount of data. (Also known as "message digest.")

See also hashing functions.

hash object
An object used to hash messages or session keys. The hash object is created by a call to CryptCreateHash. The definition of the object is defined by the CSP specified in the call.
hashing algorithm
An algorithm used to produce a hash value of some piece of data, such as a message or session key. Typical hashing algorithms include MD2, MD4, MD5, and SHA-1.
hashing functions
A set of functions used to create and destroy hash objects, get or set the parameters of a hash object, and hash data and session keys.
Hash-Based Message Authentication Code
(HMAC) A keyed hashing algorithm implemented by Microsoft cryptographic service providers. It is a more complex algorithm than the simple CBC MAC algorithm because it uses a secret symmetric key to create the hash.

It can be used with any iterated cryptographic hash algorithm, such as MD5 or SHA-1.

HCSBC
Data type which serves as a handle to a Certificate Services backup context. Its role is to maintain context state between the server and the backup APIs when a backup is being performed.
HMAC
The CryptoAPI algorithm name for the Hash-based Message Authentication Code algorithm when used with a specified hash algorithm. The CryptoAPI also references this algorithm by its algorithm identifier (CALG_HMAC) and class (ALG_CLASS_HASH).

See also Message Authentication Code algorithm.