int BN_add(BIGNUM *r, const BIGNUM *a, const BIGNUM *b);
int BN_mul(BIGNUM *r, const BIGNUM *a, const BIGNUM *b, BN_CTX *ctx);
int BN_sqr(BIGNUM *r, const BIGNUM *a,BN_CTX *ctx);
-/* BN_set_negative(): sets sign of a bignum */
+/** BN_set_negative sets sign of a BIGNUM
+ * \param b pointer to the BIGNUM object
+ * \param n 0 if the BIGNUM b should be positive and a value != 0 otherwise
+ */
void BN_set_negative(BIGNUM *b, int n);
-/* BN_get_negative(): returns 1 if the bignum is < 0 and 0 otherwise */
+/** BN_is_negative returns 1 if the BIGNUM is negative
+ * \param a pointer to the BIGNUM object
+ * \return 1 if a < 0 and 0 otherwise
+ */
#define BN_is_negative(a) ((a)->neg != 0)
int BN_div(BIGNUM *dv, BIGNUM *rem, const BIGNUM *m, const BIGNUM *d,