Handle nmap command crash

agent/nmap_agent.py

@@ -129,7 +129,11 @@ def process(self, message: msg.Message) -> None:
                         "target %s/%s was processed before, exiting", host, mask
                     )
                     return
-                scan_results, normal_results = self._scan_host(host, mask)
+                try:
+                    scan_results, normal_results = self._scan_host(host, mask)
+                except subprocess.CalledProcessError:
+                    logger.error("Nmap command failed to scan host %s", host)
+                    continue
                 logger.info("scan results %s", scan_results)
 
                 self._emit_services(scan_results, domain_name)
@@ -141,8 +145,11 @@ def process(self, message: msg.Message) -> None:
                 return
             if self._is_domain_in_scope(domain_name) is False:
                 return
-
-            scan_results, normal_results = self._scan_domain(domain_name)
+            try:
+                scan_results, normal_results = self._scan_domain(domain_name)
+            except subprocess.CalledProcessError:
+                logger.error("Nmap command failed to scan domain name %s", domain_name)
+                return
             logger.info("scan results %s", scan_results)
 
             self._emit_services(scan_results, domain_name)

tests/conftest.py

@@ -371,3 +371,11 @@ def nmap_agent_all_ports(
 
         agent = nmap_agent.NmapAgent(definition, settings)
         return agent
+
+
+@pytest.fixture
+def invalid_domain_msg() -> message.Message:
+    """Creates a dummy message of type v3.asset.domain_name for testing purposes."""
+    return message.Message.from_data(
+        selector="v3.asset.domain_name", data={"name": "-ostorlab.co"}
+    )

tests/nmap_agent_test.py

@@ -1,6 +1,7 @@
 """Unittests for Nmap agent."""
 import json
 from typing import List, Dict, Union
+import subprocess
 
 import requests_mock as rq_mock
 from ostorlab.agent.message import message
@@ -669,3 +670,20 @@ def testNmapAgent_whenIpv6AboveLimit_agentShouldRaiseError(
 
     assert len(agent_mock) == 0
     assert error_message.value.args[0] == "Subnet mask below 112 is not supported"
+
+
+def testAgentNmap_whenInvalidDomainName_doesNotCrash(
+    nmap_test_agent: nmap_agent.NmapAgent,
+    agent_mock: List[message.Message],
+    invalid_domain_msg: message.Message,
+    mocker: plugin.MockerFixture,
+) -> None:
+    """Unit test for testing agent handling of an invalid domain name."""
+    mocker.patch(
+        "subprocess.run",
+        side_effect=subprocess.CalledProcessError(255, ""),
+    )
+
+    nmap_test_agent.process(invalid_domain_msg)
+
+    assert len(agent_mock) == 0