-unsigned char *ssl_add_clienthello_dtlsext(SSL *s, unsigned char *p, unsigned char *limit);
-unsigned char *ssl_add_serverhello_dtlsext(SSL *s, unsigned char *p, unsigned char *limit);
-int ssl_parse_clienthello_dtlsext(SSL *s, unsigned char **data, unsigned char *d, int n, int *al);
-int ssl_parse_serverhello_dtlsext(SSL *s, unsigned char **data, unsigned char *d, int n, int *al);
-