AAL2GenHashDataBlock (function)

Function prototype

aat_int32 AAL2GenHashDataBlock (
    TDigipassBlob*  DPData,
    TKernelParms*   CallParms,
    aat_int32       EventWindow,
    aat_int32       StartTime,
    aat_int32       EndTime,
    aat_byte*       Salt,
    aat_int32       SaltLength,
    aat_word32      MaxRadomValue,
    aat_byte*       bKey,
    aat_int32       KeyLength,
    aat_byte*       bHashDataBlock,
    aat_int32*      HashDataBlockLength);

Description

This function generates a hash data block for the event window or time period for the given authenticator application BLOB. The content of HashDataBlock is transparent to the caller and loaded into the client-side hash verification library.

The buffer for HashDataBlock must be allocated by the client prior to the function call. It is returned as a byte string in the following format:

• Serial number on 22 ASCII characters
• Data block size on 4 bytes
• Data block version on 2 bytes
• Maximum random diversifier on 4 bytes
• Start window on 4 bytes. It can be an event value or time indicated in seconds.

• Number of hashes used on 4 bytes.

  • Since Authentication Suite Server SDK 3.17.1, the maximum number of OTP hashes is 12000.
  • Prior Authentication Suite Server SDK 3.17.1, the maximum number of OTP hashes was 3000.
• Data which contains the hashes list. Size of data is (number of hashes x 20) bytes
• CRC on 4 bytes

The allocated buffer size for bHashDataBlock must be (44 + (number of hashes x 20)) bytes. The number of hashes depends on the following parameters:

• For event-based authenticators, the HashDataBlock buffer to allocate is (44 + (EventWindow x 20)) bytes.

  The maximum value for EventWindow is 12000 since Authentication Suite Server SDK 3.17.1 and was 3000 for earlier versions.

• For time-based authenticators, the HashDataBlock buffer to allocate is (44 + ( ( (EndTime – StartTime) / TimeStep) x 20)) bytes.

  The maximum value for ( (EndTime – StartTime) / TimeStep) is 12000 since Authentication Suite Server SDK 3.17.1 and was 3000 for earlier versions.

Parameters

Return codes