gtp_v1_hdr
struct gtp_v1_hdr gh;
void gtp_v1_print_ctrl(const u_char *, u_int, struct gtp_v1_hdr *);
void gtp_v1_print_user(const u_char *, u_int, struct gtp_v1_hdr *);
struct gtp_v1_hdr *gh = (struct gtp_v1_hdr *)cp;
p += sizeof(struct gtp_v1_hdr);
p += sizeof(struct gtp_v1_hdr_ext) - sizeof(struct gtp_v1_hdr);
gtp_v1_print_ctrl(const u_char *cp, u_int hlen, struct gtp_v1_hdr *gh)
gtp_v1_print_user(const u_char *cp, u_int hlen, struct gtp_v1_hdr *gh)