-/* BN_ncopy(): like BN_copy() but copies at most the first n BN_ULONGs */
-BIGNUM *BN_ncopy(BIGNUM *a, const BIGNUM *b, size_t n);
-void BN_swap(BIGNUM *a, BIGNUM *b);
-BIGNUM *BN_bin2bn(const unsigned char *s,int len,BIGNUM *ret);
-int BN_bn2bin(const BIGNUM *a, unsigned char *to);
-BIGNUM *BN_mpi2bn(const unsigned char *s,int len,BIGNUM *ret);
-int BN_bn2mpi(const BIGNUM *a, unsigned char *to);
-int BN_sub(BIGNUM *r, const BIGNUM *a, const BIGNUM *b);
-int BN_usub(BIGNUM *r, const BIGNUM *a, const BIGNUM *b);
-int BN_uadd(BIGNUM *r, const BIGNUM *a, const BIGNUM *b);
-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);
-
-int BN_div(BIGNUM *dv, BIGNUM *rem, const BIGNUM *m, const BIGNUM *d,
- BN_CTX *ctx);
-#define BN_mod(rem,m,d,ctx) BN_div(NULL,(rem),(m),(d),(ctx))
-int BN_nnmod(BIGNUM *r, const BIGNUM *m, const BIGNUM *d, BN_CTX *ctx);
-int BN_mod_add(BIGNUM *r, const BIGNUM *a, const BIGNUM *b, const BIGNUM *m, BN_CTX *ctx);
-int BN_mod_add_quick(BIGNUM *r, const BIGNUM *a, const BIGNUM *b, const BIGNUM *m);
-int BN_mod_sub(BIGNUM *r, const BIGNUM *a, const BIGNUM *b, const BIGNUM *m, BN_CTX *ctx);
-int BN_mod_sub_quick(BIGNUM *r, const BIGNUM *a, const BIGNUM *b, const BIGNUM *m);
-int BN_mod_mul(BIGNUM *r, const BIGNUM *a, const BIGNUM *b,
- const BIGNUM *m, BN_CTX *ctx);
-int BN_mod_sqr(BIGNUM *r, const BIGNUM *a, const BIGNUM *m, BN_CTX *ctx);
-int BN_mod_lshift1(BIGNUM *r, const BIGNUM *a, const BIGNUM *m, BN_CTX *ctx);
-int BN_mod_lshift1_quick(BIGNUM *r, const BIGNUM *a, const BIGNUM *m);
-int BN_mod_lshift(BIGNUM *r, const BIGNUM *a, int n, const BIGNUM *m, BN_CTX *ctx);
-int BN_mod_lshift_quick(BIGNUM *r, const BIGNUM *a, int n, const BIGNUM *m);
+void BN_swap(BIGNUM *a, BIGNUM *b);
+BIGNUM *BN_bin2bn(const unsigned char *s, int len, BIGNUM *ret);
+int BN_bn2bin(const BIGNUM *a, unsigned char *to);
+BIGNUM *BN_mpi2bn(const unsigned char *s, int len, BIGNUM *ret);
+int BN_bn2mpi(const BIGNUM *a, unsigned char *to);
+int BN_sub(BIGNUM *r, const BIGNUM *a, const BIGNUM *b);
+int BN_usub(BIGNUM *r, const BIGNUM *a, const BIGNUM *b);
+int BN_uadd(BIGNUM *r, const BIGNUM *a, const BIGNUM *b);
+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
+ * \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_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,
+ BN_CTX *ctx);
+# define BN_mod(rem,m,d,ctx) BN_div(NULL,(rem),(m),(d),(ctx))
+int BN_nnmod(BIGNUM *r, const BIGNUM *m, const BIGNUM *d, BN_CTX *ctx);
+int BN_mod_add(BIGNUM *r, const BIGNUM *a, const BIGNUM *b, const BIGNUM *m,
+ BN_CTX *ctx);
+int BN_mod_add_quick(BIGNUM *r, const BIGNUM *a, const BIGNUM *b,
+ const BIGNUM *m);
+int BN_mod_sub(BIGNUM *r, const BIGNUM *a, const BIGNUM *b, const BIGNUM *m,
+ BN_CTX *ctx);
+int BN_mod_sub_quick(BIGNUM *r, const BIGNUM *a, const BIGNUM *b,
+ const BIGNUM *m);
+int BN_mod_mul(BIGNUM *r, const BIGNUM *a, const BIGNUM *b, const BIGNUM *m,
+ BN_CTX *ctx);
+int BN_mod_sqr(BIGNUM *r, const BIGNUM *a, const BIGNUM *m, BN_CTX *ctx);
+int BN_mod_lshift1(BIGNUM *r, const BIGNUM *a, const BIGNUM *m, BN_CTX *ctx);
+int BN_mod_lshift1_quick(BIGNUM *r, const BIGNUM *a, const BIGNUM *m);
+int BN_mod_lshift(BIGNUM *r, const BIGNUM *a, int n, const BIGNUM *m,
+ BN_CTX *ctx);
+int BN_mod_lshift_quick(BIGNUM *r, const BIGNUM *a, int n, const BIGNUM *m);