MBEDTLS_SSL_EXTENDED_MASTER_SECRET macro

\def MBEDTLS_SSL_EXTENDED_MASTER_SECRET Enable support for RFC 7627: Session Hash and Extended Master Secret Extension. This was introduced as "the proper fix" to the Triple Handshake family of attacks, but it is recommended to always use it (even if you disable renegotiation), since it actually fixes a more fundamental issue in the original SSL/TLS design, and has implications beyond Triple Handshake. Requires: MBEDTLS_SSL_PROTO_TLS1_2 Comment this macro to disable support for Extended Master Secret.