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 *);