fix: Security policy check for empty private key to improve error message

plugins/securityPolicies/ua_securitypolicy_basic128rsa15.c

@@ -659,6 +659,12 @@ policyContext_newContext_sp_basic128rsa15(UA_SecurityPolicy *securityPolicy,
     if(securityPolicy == NULL)
         return UA_STATUSCODE_BADINTERNALERROR;
 
+    if (localPrivateKey.length == 0) {
+        UA_LOG_ERROR(securityPolicy->logger, UA_LOGCATEGORY_SECURITYPOLICY,
+                     "Can not initialize security policy. Private key is empty.");
+        return UA_STATUSCODE_BADINVALIDARGUMENT;
+    }
+
     Basic128Rsa15_PolicyContext *pc = (Basic128Rsa15_PolicyContext *)
         UA_malloc(sizeof(Basic128Rsa15_PolicyContext));
     securityPolicy->policyContext = (void *)pc;

plugins/securityPolicies/ua_securitypolicy_basic256.c

@@ -610,6 +610,12 @@ policyContext_newContext_sp_basic256(UA_SecurityPolicy *securityPolicy,
     if(securityPolicy == NULL)
         return UA_STATUSCODE_BADINTERNALERROR;
 
+    if (localPrivateKey.length == 0) {
+        UA_LOG_ERROR(securityPolicy->logger, UA_LOGCATEGORY_SECURITYPOLICY,
+                     "Can not initialize security policy. Private key is empty.");
+        return UA_STATUSCODE_BADINVALIDARGUMENT;
+    }
+
     Basic256_PolicyContext *pc = (Basic256_PolicyContext *)
         UA_malloc(sizeof(Basic256_PolicyContext));
     securityPolicy->policyContext = (void *)pc;

plugins/securityPolicies/ua_securitypolicy_basic256sha256.c

@@ -650,6 +650,12 @@ policyContext_newContext_sp_basic256sha256(UA_SecurityPolicy *securityPolicy,
     if(securityPolicy == NULL)
         return UA_STATUSCODE_BADINTERNALERROR;
 
+    if (localPrivateKey.length == 0) {
+        UA_LOG_ERROR(securityPolicy->logger, UA_LOGCATEGORY_SECURITYPOLICY,
+                     "Can not initialize security policy. Private key is empty.");
+        return UA_STATUSCODE_BADINVALIDARGUMENT;
+    }
+
     Basic256Sha256_PolicyContext *pc = (Basic256Sha256_PolicyContext *)
         UA_malloc(sizeof(Basic256Sha256_PolicyContext));
     securityPolicy->policyContext = (void *)pc;