SignRecover

This function implements a single part signing or MAC operation. It can be used for either discovering the target buffer length, or for actually performing the operation.

If the target buffer address, tgt, is NULL, then the variable pointed to by plen is updated to contain the length of the output that is required to perform the operation.

If the target buffer address is not NULL, then the signing operation is performed, and the signature is placed in the output buffer.

Synopsis

#include “fmciphobj.h”
int (*SignRecover)(struct CipherObj * ctx,
void * tgt, unsigned int tlength, unsigned int * plen,
const void * src, unsigned int length);

Parameter	Description
ctx	The address of a cipher object instance.
tgt	The address of the output buffer. It may be set to NULL for output buffer length estimation.
tlength	Total number of bytes available in the output buffer.
plen	Address of a variable that will receive the number of bytes placed in the target buffer. This variable must not be NULL.
src	Address of the buffer containing the input data.
length	Number of bytes in the src buffer.

Return Value

0: The operation was successful.

Otherwise: an error occurred.

Comments

Most block cipher algorithm cipher objects do not implement this function.