X509_EXTENSION *X509V3_EXT_i2d(int ext_nid, int crit, void *ext_struc);
-int X509V3_add1_i2d(STACK_OF(X509_EXTENSION) *x, int nid, void *value, int crit, unsigned long flags);
+int X509V3_add1_i2d(STACK_OF(X509_EXTENSION) **x, int nid, void *value, int crit, unsigned long flags);
char *hex_to_string(unsigned char *buffer, long len);
unsigned char *string_to_hex(char *str, long *len);