diff --git a/cryptfs.h b/cryptfs.h
index d20d96d..a7b650f 100644
--- a/cryptfs.h
+++ b/cryptfs.h
@@ -229,11 +229,11 @@
 
   int cryptfs_crypto_complete(void);
   int cryptfs_check_passwd(const char *pw);
-  int cryptfs_verify_passwd(char *newpw);
+  int cryptfs_verify_passwd(const char *pw);
   int cryptfs_restart(void);
-  int cryptfs_enable(char *flag, int type, char *passwd, int no_ui);
+  int cryptfs_enable(const char *flag, int type, const char *passwd, int no_ui);
   int cryptfs_changepw(int type, const char *newpw);
-  int cryptfs_enable_default(char *flag, int no_ui);
+  int cryptfs_enable_default(const char *flag, int no_ui);
   int cryptfs_setup_ext_volume(const char* label, const char* real_blkdev,
           const unsigned char* key, int keysize, char* out_crypto_blkdev);
   int cryptfs_revert_ext_volume(const char* label);