Use certificate chain from keystore for server identity

common/transport/lwm2m/src/main/java/org/thingsboard/server/transport/lwm2m/bootstrap/LwM2MTransportBootstrapService.java

@@ -17,6 +17,7 @@ package org.thingsboard.server.transport.lwm2m.bootstrap;
 
 import lombok.RequiredArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
+import org.eclipse.californium.elements.util.SslContextUtil;
 import org.eclipse.californium.scandium.config.DtlsConnectorConfig;
 import org.eclipse.leshan.core.util.Hex;
 import org.eclipse.leshan.server.bootstrap.BootstrapSessionManager;
@@ -178,13 +179,14 @@ public class LwM2MTransportBootstrapService {
          * For idea => KeyStorePathResource == common/transport/lwm2m/src/main/resources/credentials: in LwM2MTransportContextServer: credentials/serverKeyStore.jks
          */
         try {
-            X509Certificate serverCertificate = (X509Certificate) serverConfig.getKeyStoreValue().getCertificate(this.bootstrapConfig.getCertificateAlias());
+            X509Certificate[] certificateChain = SslContextUtil.asX509Certificates(serverConfig.getKeyStoreValue().getCertificateChain(this.bootstrapConfig.getCertificateAlias()));
+            X509Certificate serverCertificate = certificateChain[0];
             PrivateKey privateKey = (PrivateKey) serverConfig.getKeyStoreValue().getKey(this.bootstrapConfig.getCertificateAlias(), serverConfig.getKeyStorePassword() == null ? null : serverConfig.getKeyStorePassword().toCharArray());
             PublicKey publicKey = serverCertificate.getPublicKey();
             if (privateKey != null && privateKey.getEncoded().length > 0 && publicKey != null && publicKey.getEncoded().length > 0) {
                 builder.setPublicKey(serverCertificate.getPublicKey());
                 builder.setPrivateKey(privateKey);
-                builder.setCertificateChain(new X509Certificate[]{serverCertificate});
+                builder.setCertificateChain(certificateChain);
                 this.infoParamsServerX509(serverCertificate, publicKey, privateKey);
                 return true;
             } else {

common/transport/lwm2m/src/main/java/org/thingsboard/server/transport/lwm2m/server/DefaultLwM2mTransportService.java

@@ -17,6 +17,7 @@ package org.thingsboard.server.transport.lwm2m.server;
 
 import lombok.RequiredArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
+import org.eclipse.californium.elements.util.SslContextUtil;
 import org.eclipse.californium.scandium.config.DtlsConnectorConfig;
 import org.eclipse.californium.scandium.dtls.cipher.CipherSuite;
 import org.eclipse.leshan.core.node.codec.DefaultLwM2mNodeDecoder;
@@ -47,6 +48,7 @@ import java.security.KeyFactory;
 import java.security.NoSuchAlgorithmException;
 import java.security.PrivateKey;
 import java.security.PublicKey;
+import java.security.cert.Certificate;
 import java.security.cert.CertificateEncodingException;
 import java.security.cert.X509Certificate;
 import java.security.interfaces.ECPublicKey;
@@ -185,13 +187,14 @@ public class DefaultLwM2mTransportService implements LwM2MTransportService {
 
     private boolean setBuilderX509(LeshanServerBuilder builder) {
         try {
-            X509Certificate serverCertificate = (X509Certificate) config.getKeyStoreValue().getCertificate(config.getCertificateAlias());
+            X509Certificate[] certificateChain = SslContextUtil.asX509Certificates(config.getKeyStoreValue().getCertificateChain(config.getCertificateAlias()));
+            X509Certificate serverCertificate = certificateChain[0];
             PrivateKey privateKey = (PrivateKey) config.getKeyStoreValue().getKey(config.getCertificateAlias(), config.getKeyStorePassword() == null ? null : config.getKeyStorePassword().toCharArray());
             PublicKey publicKey = serverCertificate.getPublicKey();
             if (privateKey != null && privateKey.getEncoded().length > 0 && publicKey != null && publicKey.getEncoded().length > 0) {
                 builder.setPublicKey(serverCertificate.getPublicKey());
                 builder.setPrivateKey(privateKey);
-                builder.setCertificateChain(new X509Certificate[]{serverCertificate});
+                builder.setCertificateChain(certificateChain);
                 this.infoParamsServerX509(serverCertificate, publicKey, privateKey);
                 return true;
             } else {