typedef void * (*X509V3_EXT_NEW)(void);
typedef void (*X509V3_EXT_FREE)(void *);
-typedef void * (*X509V3_EXT_D2I)(void *, unsigned char ** , long);
+typedef void * (*X509V3_EXT_D2I)(void *, const unsigned char ** , long);
typedef int (*X509V3_EXT_I2D)(void *, unsigned char **);
typedef STACK_OF(CONF_VALUE) * (*X509V3_EXT_I2V)(struct v3_ext_method *method, void *ext, STACK_OF(CONF_VALUE) *extlist);
typedef void * (*X509V3_EXT_V2I)(struct v3_ext_method *method, struct v3_ext_ctx *ctx, STACK_OF(CONF_VALUE) *values);
typedef char * (*X509V3_EXT_I2S)(struct v3_ext_method *method, void *ext);
-typedef void * (*X509V3_EXT_S2I)(struct v3_ext_method *method, struct v3_ext_ctx *ctx, char *str);
+typedef void * (*X509V3_EXT_S2I)(struct v3_ext_method *method, struct v3_ext_ctx *ctx, const char *str);
typedef int (*X509V3_EXT_I2R)(struct v3_ext_method *method, void *ext, BIO *out, int indent);
-typedef void * (*X509V3_EXT_R2I)(struct v3_ext_method *method, struct v3_ext_ctx *ctx, char *str);
+typedef void * (*X509V3_EXT_R2I)(struct v3_ext_method *method, struct v3_ext_ctx *ctx, const char *str);
/* V3 extension structure */