RSA Security 5 manual Aimac

AI_MAC

AI_MAC

Purpose:

This AI allows you to create a variable-length message authentication code (MAC) on a non-linear feedback shift register.

Type of information this allows you to use:

the MAC length parameter for the MAC algorithm

Format of info supplied to B_SetAlgorithmInfo:

pointer to a B_MAC_PARAMS structure:

typedef struct	{
unsigned int	macLen;	/* length of MAC value */

}B_MAC_PARAMS;

The minimum macLen is 2.

Format of info returned by B_GetAlgorithmInfo:

pointer to a B_MAC_PARAMS structure (see above).

Crypto-C procedures to use with algorithm object:

B_DigestInit, B_DigestUpdate, and B_DigestFinal. Supply NULL_PTR for the keyObject argument in B_DigestInit.

Algorithm methods to include in application’s algorithm chooser:

AM_MAC.

Output considerations:

The output of B_DigestFinal will be macLen bytes long.

9 6 R S A B S A F E C r y p t o - C L i b r a r y R e f e r e n c e M a n u a l