NAME

RSA_blinding_on, RSA_blinding_off − Protect the RSA operation from timing attacks

SYNOPSIS

#include <openssl/rsa.h>
int RSA_blinding_on(
        RSA ∗rsa,
        BN_CTX ∗ctx ); void RSA_blinding_off(
        RSA ∗rsa );

DESCRIPTION

RSA is vulnerable to timing attacks. In a setup where attackers can measure the time of RSA decryption or signature operations, blinding must be used to protect the RSA operation from that attack. 

The RSA_blinding_on() function turns blinding on for key rsa and generates a random blinding factor. The ctx is NULL or a pre-allocated and initialized BN_CTX. The random number generator must be seeded prior to calling the RSA_blinding_on() function. 

The RSA_blinding_off() function turns blinding off and frees the memory used for the blinding factor. 

RETURN VALUES

The RSA_blinding_on() function returns 1 on success, and 0 if an error occurred. 

The RSA_blinding_off() function returns no value. 

HISTORY

The RSA_blinding_on() and RSA_blinding_off() functions appeared in SSLeay 0.9.0. 

SEE ALSO

Functions: rsa(3), rand_ssl(3)