diff --git a/crypto/bn.h b/crypto/bn.h
index 9c529e2..a7c0628 100644
--- a/crypto/bn.h
+++ b/crypto/bn.h
@@ -385,8 +385,8 @@ int	BN_mod_exp_mont_word(BIGNUM *r, BN_ULONG a, const BIGNUM *p,
 			const BIGNUM *m, BN_CTX *ctx, BN_MONT_CTX *m_ctx);
 int	BN_mod_exp2_mont(BIGNUM *r, BIGNUM *a1, BIGNUM *p1,BIGNUM *a2,
 		BIGNUM *p2,BIGNUM *m,BN_CTX *ctx,BN_MONT_CTX *m_ctx);
-int	BN_mod_exp_simple(BIGNUM *r, BIGNUM *a, BIGNUM *p,
-	BIGNUM *m,BN_CTX *ctx);
+int	BN_mod_exp_simple(BIGNUM *r, BIGNUM *a, const BIGNUM *p,
+	const BIGNUM *m,BN_CTX *ctx);
 int	BN_mask_bits(BIGNUM *a,int n);
 int	BN_mod_mul(BIGNUM *ret, BIGNUM *a, BIGNUM *b, const BIGNUM *m, BN_CTX *ctx);
 #ifndef NO_FP_API
diff --git a/crypto/bn_ctx.c b/crypto/bn_ctx.c
index 525f74a..80f4529 100644
--- a/crypto/bn_ctx.c
+++ b/crypto/bn_ctx.c
@@ -63,7 +63,6 @@
 #include <assert.h>
 #include "bn.h"
 
-#if 0
 BN_CTX *BN_CTX_new(void)
 	{
 	BN_CTX *ret;
@@ -79,7 +78,6 @@ BN_CTX *BN_CTX_new(void)
 	ret->flags=BN_FLG_MALLOCED;
 	return(ret);
 	}
-#endif
 
 void BN_CTX_init(BN_CTX *ctx)
 	{
diff --git a/crypto/bn_exp.c b/crypto/bn_exp.c
index e512317..1c1eedb 100644
--- a/crypto/bn_exp.c
+++ b/crypto/bn_exp.c
@@ -795,7 +795,7 @@ err:
 #endif
 
 /* The old fallback, simple version :-) */
-int BN_mod_exp_simple(BIGNUM *r, BIGNUM *a, BIGNUM *p, BIGNUM *m,
+int BN_mod_exp_simple(BIGNUM *r, BIGNUM *a, const BIGNUM *p, const BIGNUM *m,
 	     BN_CTX *ctx)
 	{
 	int i,j,bits,ret=0,wstart,wend,window,wvalue,ts=0;