fixed possible NPE

common/util/src/main/java/org/thingsboard/common/util/SslUtil.java

@@ -73,7 +73,7 @@ public class SslUtil {
 
     @SneakyThrows
     public static PrivateKey readPrivateKey(String fileContent, String passStr) {
-        char[] password = StringUtils.isEmpty(passStr) ? EMPTY_PASS : passStr.toCharArray();
+        char[] password = getPassword(passStr);
 
         PrivateKey privateKey = null;
         JcaPEMKeyConverter keyConverter = new JcaPEMKeyConverter();
@@ -102,4 +102,8 @@ public class SslUtil {
         return privateKey;
     }
 
+    public static char[] getPassword(String passStr) {
+        return StringUtils.isEmpty(passStr) ? EMPTY_PASS : passStr.toCharArray();
+    }
+
 }

rule-engine/rule-engine-components/src/main/java/org/thingsboard/rule/engine/credentials/CertPemCredentials.java

@@ -47,7 +47,7 @@ public class CertPemCredentials implements ClientCredentials {
     protected String caCert;
     private String cert;
     private String privateKey;
-    private String password = "";
+    private String password;
 
     @Override
     public CredentialsType getType() {
@@ -87,7 +87,7 @@ public class CertPemCredentials implements ClientCredentials {
 
     private KeyManagerFactory createAndInitKeyManagerFactory() throws Exception {
         KeyManagerFactory kmf = KeyManagerFactory.getInstance(KeyManagerFactory.getDefaultAlgorithm());
-        kmf.init(loadKeyStore(), password.toCharArray());
+        kmf.init(loadKeyStore(), SslUtil.getPassword(password));
         return kmf;
     }
 
@@ -107,7 +107,7 @@ public class CertPemCredentials implements ClientCredentials {
             CertPath certPath = factory.generateCertPath(certificates);
             List<? extends Certificate> path = certPath.getCertificates();
             Certificate[] x509Certificates = path.toArray(new Certificate[0]);
-            keyStore.setKeyEntry(PRIVATE_KEY_ALIAS, privateKey, password.toCharArray(), x509Certificates);
+            keyStore.setKeyEntry(PRIVATE_KEY_ALIAS, privateKey, SslUtil.getPassword(password), x509Certificates);
         }
         return keyStore;
     }