Gets the parameter of the ec over GFp defined by y^2 = x^3 + a*x + b
\param group EC_GROUP object
\param p BIGNUM for the prime number
\param a BIGNUM for parameter a of the equation
\param b BIGNUM for parameter b of the equation
\param ctx BN_CTX object (optional)
\return 1 on success and 0 if an error occured
Gets the parameter of the ec over GFp defined by y^2 = x^3 + a*x + b \param group EC_GROUP object \param p BIGNUM for the prime number \param a BIGNUM for parameter a of the equation \param b BIGNUM for parameter b of the equation \param ctx BN_CTX object (optional) \return 1 on success and 0 if an error occured