diff --git a/include/mbedtls/ssl_internal.h b/include/mbedtls/ssl_internal.h
index 756360b..20e4436 100644
--- a/include/mbedtls/ssl_internal.h
+++ b/include/mbedtls/ssl_internal.h
@@ -88,6 +88,14 @@
 #endif /* MBEDTLS_SSL_PROTO_TLS1_1 */
 #endif /* MBEDTLS_SSL_PROTO_TLS1_2 */
 
+/* Shorthand for restartable */
+#if defined(MBEDTLS_ECP_RESTARTABLE) && \
+    defined(MBEDTLS_SSL_CLI_C) && \
+    defined(MBEDTLS_SSL_PROTO_TLS1_2) && \
+    defined(MBEDTLS_KEY_EXCHANGE_ECDHE_ECDSA_ENABLED)
+#define MBEDTLS_SSL__ECP_RESTARTABLE
+#endif
+
 #define MBEDTLS_SSL_INITIAL_HANDSHAKE           0
 #define MBEDTLS_SSL_RENEGOTIATION_IN_PROGRESS   1   /* In progress */
 #define MBEDTLS_SSL_RENEGOTIATION_DONE          2   /* Done or aborted */
@@ -218,6 +226,14 @@
     mbedtls_x509_crl *sni_ca_crl;       /*!< trusted CAs CRLs from SNI      */
 #endif /* MBEDTLS_SSL_SERVER_NAME_INDICATION */
 #endif /* MBEDTLS_X509_CRT_PARSE_C */
+#if defined(MBEDTLS_SSL__ECP_RESTARTABLE)
+    enum {
+        ssl_ecrs_init = 0,              /*!< just getting started           */
+        ssl_ecrs_ecdh_public_done,      /*!< wrote ECDHE public share       */
+        ssl_ecrs_ecdh_completed,        /*!< completed ECDHE key exchange   */
+    } ecrs_state;                       /*!< state for restartable ECC      */
+    size_t ecrs_n;                      /*!< place for seving a length      */
+#endif
 #if defined(MBEDTLS_SSL_PROTO_DTLS)
     unsigned int out_msg_seq;           /*!<  Outgoing handshake sequence number */
     unsigned int in_msg_seq;            /*!<  Incoming handshake sequence number */