Add support for secp256k1 arithmetic
diff --git a/include/polarssl/ecp.h b/include/polarssl/ecp.h
index 1e9e737..1bc989e 100644
--- a/include/polarssl/ecp.h
+++ b/include/polarssl/ecp.h
@@ -68,6 +68,9 @@
     POLARSSL_ECP_DP_M255,           /*!< Curve25519               */
     POLARSSL_ECP_DP_M383,           /*!< (not implemented yet)    */
     POLARSSL_ECP_DP_M511,           /*!< (not implemented yet)    */
+    POLARSSL_ECP_DP_SECP192K1,      /*!< (not implemented yet)    */
+    POLARSSL_ECP_DP_SECP224K1,      /*!< (not implemented yet)    */
+    POLARSSL_ECP_DP_SECP256K1,      /*!< 256-bits Koblitz curve   */
 } ecp_group_id;
 
 /**