Import mbedtls-3.6.0

Imports Mbed TLS 3.6.0 from https://github.com/Mbed-TLS/mbedtls.git
tags mbedtls-3.6.0, v3.6.0

Files that are not needed are removed:

cd lib/libmbedtls
rm -rf mbedtls
cp -R path/to/mbedtls-3.6.0/mbedtls .
cd mbedtls
rm CMakeLists.txt DartConfiguration.tcl Makefile
rm .gitignore .travis.yml .pylintrc .globalrc .mypy.ini BRANCHES.md
rm include/.gitignore include/CMakeLists.txt library/.gitignore
rm library/CMakeLists.txt library/Makefile
rm -r cmake
rm -rf .git .github doxygen configs programs scripts tests visualc
rm -rf 3rdparty ChangeLog.d docs pkgconfig .gitmodules .readthedocs.yaml
rm library/mps_*
cd ..
git add mbedtls

This time we leave library/psa_* present to enable TLS 1.3 features.

This is a complete overwrite of previous code so earlier changes in the
previous branch import/mbedtls-3.4.0 will be added on top of this commit.

Signed-off-by: Tom Van Eyck <tom.vaneyck@kuleuven.be>
Acked-by: Jens Wiklander <jens.wiklander@linaro.org>
diff --git a/lib/libmbedtls/mbedtls/library/ecdsa.c b/lib/libmbedtls/mbedtls/library/ecdsa.c
index eb3c303..2f7a996 100644
--- a/lib/libmbedtls/mbedtls/library/ecdsa.c
+++ b/lib/libmbedtls/mbedtls/library/ecdsa.c
@@ -2,25 +2,13 @@
  *  Elliptic curve DSA
  *
  *  Copyright The Mbed TLS Contributors
- *  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.
+ *  SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
  */
 
 /*
  * References:
  *
- * SEC1 http://www.secg.org/index.php?action=secg,docs_secg
+ * SEC1 https://www.secg.org/sec1-v2.pdf
  */
 
 #include "common.h"
@@ -234,6 +222,19 @@
 }
 #endif /* ECDSA_DETERMINISTIC || !ECDSA_SIGN_ALT || !ECDSA_VERIFY_ALT */
 
+int mbedtls_ecdsa_can_do(mbedtls_ecp_group_id gid)
+{
+    switch (gid) {
+#ifdef MBEDTLS_ECP_DP_CURVE25519_ENABLED
+        case MBEDTLS_ECP_DP_CURVE25519: return 0;
+#endif
+#ifdef MBEDTLS_ECP_DP_CURVE448_ENABLED
+        case MBEDTLS_ECP_DP_CURVE448: return 0;
+#endif
+        default: return 1;
+    }
+}
+
 #if !defined(MBEDTLS_ECDSA_SIGN_ALT)
 /*
  * Compute ECDSA signature of a hashed message (SEC1 4.1.3)
@@ -360,7 +361,7 @@
 
 #if defined(MBEDTLS_ECP_RESTARTABLE)
     if (rs_ctx != NULL && rs_ctx->sig != NULL) {
-        mbedtls_mpi_copy(r, pr);
+        MBEDTLS_MPI_CHK(mbedtls_mpi_copy(r, pr));
     }
 #endif
 
@@ -373,19 +374,6 @@
     return ret;
 }
 
-int mbedtls_ecdsa_can_do(mbedtls_ecp_group_id gid)
-{
-    switch (gid) {
-#ifdef MBEDTLS_ECP_DP_CURVE25519_ENABLED
-        case MBEDTLS_ECP_DP_CURVE25519: return 0;
-#endif
-#ifdef MBEDTLS_ECP_DP_CURVE448_ENABLED
-        case MBEDTLS_ECP_DP_CURVE448: return 0;
-#endif
-        default: return 1;
-    }
-}
-
 /*
  * Compute ECDSA signature of a hashed message
  */
@@ -447,7 +435,7 @@
     MBEDTLS_MPI_CHK(mbedtls_mpi_write_binary(d, data, grp_len));
     MBEDTLS_MPI_CHK(derive_mpi(grp, &h, buf, blen));
     MBEDTLS_MPI_CHK(mbedtls_mpi_write_binary(&h, data + grp_len, grp_len));
-    mbedtls_hmac_drbg_seed_buf(p_rng, md_info, data, 2 * grp_len);
+    MBEDTLS_MPI_CHK(mbedtls_hmac_drbg_seed_buf(p_rng, md_info, data, 2 * grp_len));
 
 #if defined(MBEDTLS_ECP_RESTARTABLE)
     if (rs_ctx != NULL && rs_ctx->det != NULL) {