crypto: cast6 - prepare generic module for optimized implementations

Rename cast6 module to cast6_generic to allow autoloading of optimized
implementations. Generic functions and s-boxes are exported to be able to use
them within optimized implementations.

Signed-off-by: Johannes Goetzfried <Johannes.Goetzfried@informatik.stud.uni-erlangen.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
diff --git a/include/crypto/cast6.h b/include/crypto/cast6.h
new file mode 100644
index 0000000..02dde6b
--- /dev/null
+++ b/include/crypto/cast6.h
@@ -0,0 +1,23 @@
+#ifndef _CRYPTO_CAST6_H
+#define _CRYPTO_CAST6_H
+
+#include <linux/types.h>
+#include <linux/crypto.h>
+
+#define CAST6_BLOCK_SIZE 16
+#define CAST6_MIN_KEY_SIZE 16
+#define CAST6_MAX_KEY_SIZE 32
+
+struct cast6_ctx {
+	u32 Km[12][4];
+	u8 Kr[12][4];
+};
+
+int __cast6_setkey(struct cast6_ctx *ctx, const u8 *key,
+		   unsigned int keylen, u32 *flags);
+int cast6_setkey(struct crypto_tfm *tfm, const u8 *key, unsigned int keylen);
+
+void __cast6_encrypt(struct cast6_ctx *ctx, u8 *dst, const u8 *src);
+void __cast6_decrypt(struct cast6_ctx *ctx, u8 *dst, const u8 *src);
+
+#endif