diff --git a/3rdparty/everest/library/everest.c b/3rdparty/everest/library/everest.c
new file mode 100644
index 0000000..2b7861d
--- /dev/null
+++ b/3rdparty/everest/library/everest.c
@@ -0,0 +1,151 @@
+/*
+ *  Interface to code from Project Everest
+ *
+ *  Copyright 2016-2018 INRIA and Microsoft Corporation
+ *  SPDX-License-Identifier: Apache-2.0
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License"); you may
+ *  not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *  http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ *
+ *  This file is part of Mbed TLS (https://tls.mbed.org).
+ */
+
+#if !defined(MBEDTLS_CONFIG_FILE)
+#include "mbedtls/config.h"
+#else
+#include MBEDTLS_CONFIG_FILE
+#endif
+
+#include <string.h>
+
+#include "mbedtls/ecdh.h"
+
+#include "everest/x25519.h"
+#include "everest/everest.h"
+
+#if defined(MBEDTLS_PLATFORM_C)
+#include "mbedtls/platform.h"
+#else
+#define mbedtls_calloc calloc
+#define mbedtls_free   free
+#endif
+
+int mbedtls_everest_setup( mbedtls_ecdh_context *ctx, int grp )
+{
+    if( grp != MBEDTLS_ECP_DP_CURVE25519 )
+        return MBEDTLS_ERR_ECP_BAD_INPUT_DATA;
+
+    ctx->var = MBEDTLS_ECDH_VARIANT_EVEREST;
+    ctx->grp_id = grp;
+
+    ctx->ctx.everest_ecdh.ctx = mbedtls_calloc( 1, sizeof( mbedtls_x25519_context ) );
+    mbedtls_x25519_init( ctx->ctx.everest_ecdh.ctx );
+
+    return 0;
+}
+
+void mbedtls_everest_free( mbedtls_ecdh_context *ctx )
+{
+    mbedtls_ecdh_context_everest *everest_ctx = &ctx->ctx.everest_ecdh;
+    mbedtls_x25519_context *x25519_ctx = ( mbedtls_x25519_context* )everest_ctx->ctx;
+
+    mbedtls_x25519_free( x25519_ctx );
+    mbedtls_free( x25519_ctx );
+
+    ctx->var = MBEDTLS_ECDH_VARIANT_NONE;
+    ctx->grp_id = MBEDTLS_ECP_DP_NONE;
+}
+
+int mbedtls_everest_make_params( mbedtls_ecdh_context *ctx, size_t *olen,
+                                 unsigned char *buf, size_t blen,
+                                 int( *f_rng )( void *, unsigned char *, size_t ),
+                                 void *p_rng )
+{
+    int ret = 0;
+    size_t grp_len;
+    mbedtls_ecp_group grp;
+    mbedtls_ecdh_context_everest *everest_ctx = &ctx->ctx.everest_ecdh;
+    mbedtls_x25519_context *x25519_ctx = ( mbedtls_x25519_context* )everest_ctx->ctx;
+
+    if( ctx->var != MBEDTLS_ECDH_VARIANT_EVEREST )
+        return MBEDTLS_ERR_MPI_BAD_INPUT_DATA;
+
+    mbedtls_ecp_group_init( &grp );
+
+    if( ( ret = mbedtls_x25519_make_params( x25519_ctx, olen, buf, blen, f_rng, p_rng ) ) != 0 )
+        return MBEDTLS_ERR_ECP_BAD_INPUT_DATA;
+
+    mbedtls_ecp_group_load( &grp, MBEDTLS_ECP_DP_CURVE25519 );
+    ret = mbedtls_ecp_tls_write_group( &grp, &grp_len, buf, blen );
+    mbedtls_ecp_group_free( &grp );
+    if (ret != 0)
+        return( ret );
+
+    buf += grp_len;
+    blen -= grp_len;
+
+    if( blen < 32 )
+        return MBEDTLS_ERR_ECP_BUFFER_TOO_SMALL;
+
+    memcpy( x25519_ctx->peer_point, buf, 32 );
+    *olen = grp_len + 1 + 32;
+    return( ret );
+}
+
+int mbedtls_everest_read_params( mbedtls_ecdh_context *ctx,
+                                 const unsigned char **buf, const unsigned char *end )
+{
+    mbedtls_ecdh_context_everest *everest_ctx = &ctx->ctx.everest_ecdh;
+    mbedtls_x25519_context *x25519_ctx = ( mbedtls_x25519_context* )everest_ctx->ctx;
+    if( ctx->var != MBEDTLS_ECDH_VARIANT_EVEREST ) return MBEDTLS_ERR_MPI_BAD_INPUT_DATA;
+    return mbedtls_x25519_read_params( x25519_ctx, buf, end );
+}
+
+int mbedtls_everest_get_params( mbedtls_ecdh_context *ctx, const mbedtls_ecp_keypair *key,
+    int side )
+{
+    mbedtls_ecdh_context_everest *everest_ctx = &ctx->ctx.everest_ecdh;
+    mbedtls_x25519_context *x25519_ctx = ( mbedtls_x25519_context* )everest_ctx->ctx;
+    if( ctx->var != MBEDTLS_ECDH_VARIANT_EVEREST ) return MBEDTLS_ERR_MPI_BAD_INPUT_DATA;
+    return mbedtls_x25519_get_params( x25519_ctx, key, side );
+}
+
+int mbedtls_everest_make_public( mbedtls_ecdh_context *ctx, size_t *olen,
+                                 unsigned char *buf, size_t blen,
+                                 int( *f_rng )( void *, unsigned char *, size_t ),
+                                 void *p_rng )
+{
+    mbedtls_ecdh_context_everest *everest_ctx = &ctx->ctx.everest_ecdh;
+    mbedtls_x25519_context *x25519_ctx = ( mbedtls_x25519_context* )everest_ctx->ctx;
+    if( ctx->var != MBEDTLS_ECDH_VARIANT_EVEREST ) return MBEDTLS_ERR_MPI_BAD_INPUT_DATA;
+    return mbedtls_x25519_make_public( x25519_ctx, olen, buf, blen, f_rng, p_rng );
+}
+
+int mbedtls_everest_read_public( mbedtls_ecdh_context *ctx,
+                                 const unsigned char *buf, size_t blen )
+{
+    mbedtls_ecdh_context_everest *everest_ctx = &ctx->ctx.everest_ecdh;
+    mbedtls_x25519_context *x25519_ctx = ( mbedtls_x25519_context* )everest_ctx->ctx;
+    if( ctx->var != MBEDTLS_ECDH_VARIANT_EVEREST ) return MBEDTLS_ERR_MPI_BAD_INPUT_DATA;
+    return mbedtls_x25519_read_public ( x25519_ctx, buf, blen );
+}
+
+int mbedtls_everest_calc_secret( mbedtls_ecdh_context *ctx, size_t *olen,
+                                 unsigned char *buf, size_t blen,
+                                 int( *f_rng )( void *, unsigned char *, size_t ),
+                                 void *p_rng )
+{
+    mbedtls_ecdh_context_everest *everest_ctx = &ctx->ctx.everest_ecdh;
+    mbedtls_x25519_context *x25519_ctx = ( mbedtls_x25519_context* )everest_ctx->ctx;
+    if( ctx->var != MBEDTLS_ECDH_VARIANT_EVEREST ) return MBEDTLS_ERR_MPI_BAD_INPUT_DATA;
+    return mbedtls_x25519_calc_secret( x25519_ctx, olen, buf, blen, f_rng, p_rng );
+}