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+/**
+ * @file
+ * Hashing module documentation file.
+ */
+
+/**
+ * @addtogroup hashing_module Hashing module
+ * 
+ * The Hashing module provides one-way hashing functions. Such functions can be
+ * used for creating a hash message authentication code (HMAC) when sending a 
+ * message. Such a HMAC can be used in combination with a private key
+ * for authentication, which is a message integrity control. 
+ * The following hashing-algorithms are provided:
+ * - MD2, MD4, MD5 128-bit one-way hash functions by Ron Rivest (see 
+ *   \c md2_hmac(),\c md4_hmac() and\c md5_hmac()).
+ * - SHA-1, SHA-256, SHA-384/512 160-bit or more one-way hash functions by 
+ *   NIST and NSA (see\c sha1_hmac(),\c sha2_hmac() and\c sha4_hmac()).
+ *
+ * This module provides one-way hashing which can be used for authentication.
+ */