From 09245f076670ddca7c3838c39d7a67e52a656c63 Mon Sep 17 00:00:00 2001
From: Eduardo Montoya <edmont@users.noreply.github.com>
Date: Wed, 10 Mar 2021 19:10:31 +0100
Subject: [PATCH] [dtls] fix ECDSA configuration for newer mbed TLS versions
 (#6261)

When using newer versions of mbed TLS, two issues appear when using
`OPENTHREAD_ECDSA`:
- An empty list of configuration hashes is treated as a configuration
error: DTLS fails.
- Identifiers with double underscore are not used anymore: signature
hashes configuration is not included.

This commit addresses both issues.
---
 src/core/meshcop/dtls.cpp | 6 +++---
 src/core/meshcop/dtls.hpp | 2 +-
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/src/core/meshcop/dtls.cpp b/src/core/meshcop/dtls.cpp
index 1bdbc5c9b..763205d6e 100644
--- a/src/core/meshcop/dtls.cpp
+++ b/src/core/meshcop/dtls.cpp
@@ -56,8 +56,8 @@ namespace ot {
 namespace MeshCoP {
 
 const mbedtls_ecp_group_id Dtls::sCurves[] = {MBEDTLS_ECP_DP_SECP256R1, MBEDTLS_ECP_DP_NONE};
-#ifdef MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED
-const int Dtls::sHashes[] = {MBEDTLS_MD_NONE};
+#if defined(MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED) || defined(MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED)
+const int Dtls::sHashes[] = {MBEDTLS_MD_SHA256, MBEDTLS_MD_NONE};
 #endif
 
 Dtls::Dtls(Instance &aInstance, bool aLayerTwoSecurity)
@@ -284,7 +284,7 @@ otError Dtls::Setup(bool aClient)
     if (mCipherSuites[0] == MBEDTLS_TLS_ECJPAKE_WITH_AES_128_CCM_8)
     {
         mbedtls_ssl_conf_curves(&mConf, sCurves);
-#ifdef MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED
+#if defined(MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED) || defined(MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED)
         mbedtls_ssl_conf_sig_hashes(&mConf, sHashes);
 #endif
     }
diff --git a/src/core/meshcop/dtls.hpp b/src/core/meshcop/dtls.hpp
index a3cc41411..4fbbdff0c 100644
--- a/src/core/meshcop/dtls.hpp
+++ b/src/core/meshcop/dtls.hpp
@@ -414,7 +414,7 @@ private:
     uint8_t mPskLength;
 
     static const mbedtls_ecp_group_id sCurves[];
-#ifdef MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED
+#if defined(MBEDTLS_KEY_EXCHANGE__WITH_CERT__ENABLED) || defined(MBEDTLS_KEY_EXCHANGE_WITH_CERT_ENABLED)
     static const int sHashes[];
 #endif