diff --git a/crypto/cast/c_cfb64.c b/crypto/cast/c_cfb64.c
index 50d234b4667a6a3b4aaad1bee8715f13c9cee3c6..095e05a563a42ceb3fd88f0fb61ce258f90fdb1f 100644
--- a/crypto/cast/c_cfb64.c
+++ b/crypto/cast/c_cfb64.c
@@ -64,8 +64,9 @@
  * 64bit block we have used is contained in *num;
  */
 
-void CAST_cfb64_encrypt(unsigned char *in, unsigned char *out, long length,
-	     CAST_KEY *schedule, unsigned char *ivec, int *num, int encrypt)
+void CAST_cfb64_encrypt(const unsigned char *in, unsigned char *out,
+			long length, CAST_KEY *schedule, unsigned char *ivec,
+			int *num, int _encrypt)
 	{
 	register CAST_LONG v0,v1,t;
 	register int n= *num;
@@ -73,8 +74,8 @@ void CAST_cfb64_encrypt(unsigned char *in, unsigned char *out, long length,
 	CAST_LONG ti[2];
 	unsigned char *iv,c,cc;
 
-	iv=(unsigned char *)ivec;
-	if (encrypt)
+	iv=ivec;
+	if (_encrypt)
 		{
 		while (l--)
 			{
@@ -83,10 +84,10 @@ void CAST_cfb64_encrypt(unsigned char *in, unsigned char *out, long length,
 				n2l(iv,v0); ti[0]=v0;
 				n2l(iv,v1); ti[1]=v1;
 				CAST_encrypt((CAST_LONG *)ti,schedule);
-				iv=(unsigned char *)ivec;
+				iv=ivec;
 				t=ti[0]; l2n(t,iv);
 				t=ti[1]; l2n(t,iv);
-				iv=(unsigned char *)ivec;
+				iv=ivec;
 				}
 			c= *(in++)^iv[n];
 			*(out++)=c;
@@ -103,10 +104,10 @@ void CAST_cfb64_encrypt(unsigned char *in, unsigned char *out, long length,
 				n2l(iv,v0); ti[0]=v0;
 				n2l(iv,v1); ti[1]=v1;
 				CAST_encrypt((CAST_LONG *)ti,schedule);
-				iv=(unsigned char *)ivec;
+				iv=ivec;
 				t=ti[0]; l2n(t,iv);
 				t=ti[1]; l2n(t,iv);
-				iv=(unsigned char *)ivec;
+				iv=ivec;
 				}
 			cc= *(in++);
 			c=iv[n];
diff --git a/crypto/cast/c_ecb.c b/crypto/cast/c_ecb.c
index 4b523ffc7576e2be783d35c56ff2c668634747a9..e237ebcac43356fcb91950ad7b7d85272abfb0ea 100644
--- a/crypto/cast/c_ecb.c
+++ b/crypto/cast/c_ecb.c
@@ -62,14 +62,14 @@
 
 char *CAST_version="CAST" OPENSSL_VERSION_PTEXT;
 
-void CAST_ecb_encrypt(unsigned char *in, unsigned char *out, CAST_KEY *ks,
-	     int encrypt)
+void CAST_ecb_encrypt(const unsigned char *in, unsigned char *out,
+		      CAST_KEY *ks, int _encrypt)
 	{
 	CAST_LONG l,d[2];
 
 	n2l(in,l); d[0]=l;
 	n2l(in,l); d[1]=l;
-	if (encrypt)
+	if (_encrypt)
 		CAST_encrypt(d,ks);
 	else
 		CAST_decrypt(d,ks);
diff --git a/crypto/cast/c_enc.c b/crypto/cast/c_enc.c
index b62b4680b0c0d3f877da075207beeece535a1487..ef70c8898121642febcce7162c8aa67a0ca06ccb 100644
--- a/crypto/cast/c_enc.c
+++ b/crypto/cast/c_enc.c
@@ -123,15 +123,15 @@ void CAST_decrypt(CAST_LONG *data, CAST_KEY *key)
 	data[0]=r&0xffffffffL;
 	}
 
-void CAST_cbc_encrypt(unsigned char *in, unsigned char *out, long length,
-	     CAST_KEY *ks, unsigned char *iv, int encrypt)
+void CAST_cbc_encrypt(const unsigned char *in, unsigned char *out, long length,
+	     CAST_KEY *ks, unsigned char *iv, int _encrypt)
 	{
 	register CAST_LONG tin0,tin1;
 	register CAST_LONG tout0,tout1,xor0,xor1;
 	register long l=length;
 	CAST_LONG tin[2];
 
-	if (encrypt)
+	if (_encrypt)
 		{
 		n2l(iv,tout0);
 		n2l(iv,tout1);
diff --git a/crypto/cast/c_ofb64.c b/crypto/cast/c_ofb64.c
index 4249870d9e34e6a7abcca751a7888f6a52d267a5..fd0469a62faa73def09d3516bb66d5813d216229 100644
--- a/crypto/cast/c_ofb64.c
+++ b/crypto/cast/c_ofb64.c
@@ -63,8 +63,9 @@
  * used.  The extra state information to record how much of the
  * 64bit block we have used is contained in *num;
  */
-void CAST_ofb64_encrypt(unsigned char *in, unsigned char *out, long length,
-	     CAST_KEY *schedule, unsigned char *ivec, int *num)
+void CAST_ofb64_encrypt(const unsigned char *in, unsigned char *out,
+			long length, CAST_KEY *schedule, unsigned char *ivec,
+			int *num)
 	{
 	register CAST_LONG v0,v1,t;
 	register int n= *num;
@@ -75,7 +76,7 @@ void CAST_ofb64_encrypt(unsigned char *in, unsigned char *out, long length,
 	unsigned char *iv;
 	int save=0;
 
-	iv=(unsigned char *)ivec;
+	iv=ivec;
 	n2l(iv,v0);
 	n2l(iv,v1);
 	ti[0]=v0;
@@ -100,7 +101,7 @@ void CAST_ofb64_encrypt(unsigned char *in, unsigned char *out, long length,
 		{
 		v0=ti[0];
 		v1=ti[1];
-		iv=(unsigned char *)ivec;
+		iv=ivec;
 		l2n(v0,iv);
 		l2n(v1,iv);
 		}
diff --git a/crypto/cast/cast.h b/crypto/cast/cast.h
index 215356dbe4aad46ec030f51585f9fe889632be32..6cc5e8aa8cf046c125032e38ef7a5c4b3647bbe3 100644
--- a/crypto/cast/cast.h
+++ b/crypto/cast/cast.h
@@ -83,16 +83,18 @@ typedef struct cast_key_st
 
  
 void CAST_set_key(CAST_KEY *key, int len, unsigned char *data);
-void CAST_ecb_encrypt(unsigned char *in,unsigned char *out,CAST_KEY *key,
-	int enc);
+void CAST_ecb_encrypt(const unsigned char *in,unsigned char *out,CAST_KEY *key,
+		      int enc);
 void CAST_encrypt(CAST_LONG *data,CAST_KEY *key);
 void CAST_decrypt(CAST_LONG *data,CAST_KEY *key);
-void CAST_cbc_encrypt(unsigned char *in, unsigned char *out, long length,
-	CAST_KEY *ks, unsigned char *iv, int enc);
-void CAST_cfb64_encrypt(unsigned char *in, unsigned char *out, long length,
-	CAST_KEY *schedule, unsigned char *ivec, int *num, int enc);
-void CAST_ofb64_encrypt(unsigned char *in, unsigned char *out, long length,
-	CAST_KEY *schedule, unsigned char *ivec, int *num);
+void CAST_cbc_encrypt(const unsigned char *in, unsigned char *out, long length,
+		      CAST_KEY *ks, unsigned char *iv, int enc);
+void CAST_cfb64_encrypt(const unsigned char *in, unsigned char *out,
+			long length, CAST_KEY *schedule, unsigned char *ivec,
+			int *num, int enc);
+void CAST_ofb64_encrypt(const unsigned char *in, unsigned char *out, 
+			long length, CAST_KEY *schedule, unsigned char *ivec,
+			int *num);
 
 #ifdef  __cplusplus
 }