-extern void dns_add_answer(int type, uint8_t *rdata, uint16_t rdlength);
-extern void dns_send_answer(struct uloop_fd *u, char *answer);
-extern char* dns_consume_name(uint8_t *base, int blen, uint8_t **data, int *len);
+extern void dns_add_answer(int type, const uint8_t *rdata, uint16_t rdlength);
+extern void dns_send_answer(struct uloop_fd *u, const char *answer);
+extern char* dns_consume_name(const uint8_t *base, int blen, uint8_t **data, int *len);