extern bool send_req_key(struct node_t *);
extern bool send_ans_key(struct node_t *);
extern bool send_tcppacket(struct connection_t *, const struct vpn_packet_t *);
extern bool send_req_key(struct node_t *);
extern bool send_ans_key(struct node_t *);
extern bool send_tcppacket(struct connection_t *, const struct vpn_packet_t *);
extern bool send_udp_info(struct node_t *, struct node_t *);
extern bool send_mtu_info(struct node_t *, struct node_t *, int);
extern bool send_udp_info(struct node_t *, struct node_t *);
extern bool send_mtu_info(struct node_t *, struct node_t *, int);
extern bool req_key_h(struct connection_t *, const char *);
extern bool ans_key_h(struct connection_t *, const char *);
extern bool tcppacket_h(struct connection_t *, const char *);
extern bool req_key_h(struct connection_t *, const char *);
extern bool ans_key_h(struct connection_t *, const char *);
extern bool tcppacket_h(struct connection_t *, const char *);
extern bool control_h(struct connection_t *, const char *);
extern bool udp_info_h(struct connection_t *, const char *);
extern bool mtu_info_h(struct connection_t *, const char *);
extern bool control_h(struct connection_t *, const char *);
extern bool udp_info_h(struct connection_t *, const char *);
extern bool mtu_info_h(struct connection_t *, const char *);