mbx_sm4_xts_set_keys_mb16

Schedules two 16-byte keys from a 32-byte key, for 16 buffers, prior to encryption/decryption.

Syntax

mbx_status16 mbx_sm4_xts_set_keys_mb16(mbx_sm4_key_schedule* key_sched1, mbx_sm4_key_schedule* key_sched2, const sm4_xts_key* pa_key[SM4_LINES]);

Include Files

crypto_mb/sm4.h

Parameters

key_sched1	Array of scheduled keys (from first 16 bytes of key) for up to 16 buffers.
key_sched2	Array of scheduled keys (from second 16 bytes of key) for up to 16 buffers.
pa_key	Array of up to 16 pointers to the SM4-XTS 32-byte secret keys.

Description

Sets up key schedule using user-supplied secret keys passed through pa_key with all necessary key material for both encryption and decryption operations. It uses the first 16 bytes of each 32-byte key to schedule key_sched1 and the second 16 bytes of each 32-byte key to schedule key_sched2.

Return Values

The mbx_sm4_set_key_mb16() function returns the status that indicates whether the operation completed successfully or not. The status value of 0 indicates that the key schedule was successfully initialized. In case of non-zero status value, MBX_GET_HIGH_PART_STS16() and MBX_GET_LOW_PART_STS16() can help to get the low and high parts of the mbx_status16, which can be analyzed separately with MBX_GET_STS() call. The low part includes first eight statuses, while the high part includes remaining eight statuses for each operation.