RSA Security 5 manual A p t e r 2 a l g o r i t h m I n f o Ty p e s 149

AI_PKCS_OAEP_RSAPublic

a pointer to an A_PKCS_OAEP_PARAMS structure:

typedef struct {
unsigned char*	hashFunc;
ITEM	hashFuncParams;
unsigned char*	maskGenFunc;
ITEM	maskGenFuncParams;
unsigned char*	maskGenFuncUnderlyingAlg;
ITEM	maskGenFuncUnderlyingAlgParams;
unsigned char*	pSourceFunc;
ITEM	pSourceParams;

}A_PKCS_OAEP_PARAMS;

The parameters are as follows:

hashFunc determines the digest function. Currently, it may contain a NULL_PTR or a pointer to the null-terminated ASCII string, “sha1”. In both cases SHA1 will become the digest function.

maskGenFunc determines the mask generator function. Currently, it may contain a NULL_PTR or a pointer to the null-terminated ASCII string, “mgf1”. In both cases MGF1 will become the mask generator function.

maskGenFuncUnderlyingAlg may contain a NULL_PTR or a pointer to the null-terminated ASCII string, “sha1”. In both cases SHA1 will become the underlying algorithm.

pSourceFunc is the method for determining the PKCS #1 v2.0 OAEP parameter, P. pSourceFunc may contain a NULL_PTR or a pointer to the null-terminated ASCII string, “specifiedParameters”. In both cases “specifiedParameters” will become the pSource method.

If pSourceFunc is “specifiedParameters” and if pSourceParams.len is 0, then P is assumed to be empty. pSourceParams may also be initialized to the caller's data as in this example:

pSourceParams.len = sizeof(dataObject); pSourceParams.data = &dataObject;

hashFuncParams, maskGenFuncParams, and maskGenFuncUnderlyingAlgParams are available to provide for future growth. The caller should initialize these parameters as ITEM types as follows:

C h a p t e r 2 A l g o r i t h m I n f o Ty p e s 149