add open port checker

Author: berthubert

README.md

@@ -128,6 +128,8 @@ rrsig{server="100.25.31.6", name="berthub.eu"}
 scaryports={25, 80, 110, 443, 3000, 3306, 5000, 5432, 8000, 8080, 8888}
 tcpportclosed{servers={"100.25.31.6"}, ports=scaryports}
 
+tcpportopen{servers={"192.0.2.1"}, ports={80}}
+
 -- Check if DNS is serving what it should be
 dns{server="100.25.31.6", name="berthub.eu", type="A",
 	acceptable={"86.82.68.237", "217.100.190.174"}}
@@ -191,7 +193,6 @@ if they did not lead to notifications.
 
 ## Todo
 
- * Generic port *open* test
  * HTTP *POST* support
  * HTTP JSON check
  * Performance tests ("average response time past hour > 100ms")

luabridge.cc

@@ -100,6 +100,10 @@ void initLua()
   g_lua.set_function("tcpportclosed", [&](sol::table data) {
     g_checkers.emplace_back(make_unique<TCPPortClosedChecker>(data));
   });
+  g_lua.set_function("tcpportopen", [&](sol::table data) {
+    g_checkers.emplace_back(make_unique<TCPPortOpenChecker>(data));
+  });
+
   g_lua.set_function("dns", [&](sol::table data) {
     g_checkers.emplace_back(make_unique<DNSChecker>(data));
   });

netmon.cc

@@ -60,6 +60,57 @@ CheckResult TCPPortClosedChecker::perform()
   return cr;
 }
 
+TCPPortOpenChecker::TCPPortOpenChecker(sol::table data) : Checker(data)
+{
+  checkLuaTable(data, {"servers", "ports"});
+  for(const auto& s: data.get<vector<string>>("servers")) {
+    d_servers.insert(ComboAddress(s));
+  }
+  for(int s: data.get<vector<int>>("ports")) {
+    d_ports.insert(s);
+  }
+}
+
+
+CheckResult TCPPortOpenChecker::perform()
+{
+  CheckResult cr;
+  
+  for(const auto& s : d_servers) {
+    for(const auto& p : d_ports) {
+      int ret=-1;
+      ComboAddress rem=s;
+      rem.setPort(p);
+
+      try {
+        Socket sock(s.sin4.sin_family, SOCK_STREAM);
+        SetNonBlocking(sock);
+        //fmt::print("Going to connect to {}\n", rem.toStringWithPort());
+        ret = SConnectWithTimeout(sock, rem, 1);
+      }
+      catch(exception& e) {
+        //        fmt::print("Could not connnect to TCP {}: {}\n",
+        //           rem.toStringWithPort(), e.what());
+	cr.d_reasons[rem.toStringWithPort()].push_back(fmt::format("Unable to connect to TCP {}: {}",
+								   rem.toStringWithPort(), e.what()));
+
+        continue;
+      }
+      catch(...) {
+	cr.d_reasons[rem.toStringWithPort()].push_back(fmt::format("Unable to connect to TCP {}",
+								   rem.toStringWithPort()));
+
+        continue;
+      }
+      if(ret < 0) {
+        cr.d_reasons[rem.toStringWithPort()].push_back(fmt::format("Unable ot connect to TCP {}: ", rem.toStringWithPort(),
+								   strerror(errno)));
+      }
+    }
+  }
+  return cr;
+}
+
 
 // XXX needs switch to select IPv4 or IPv6 or happy eyeballs?
 HTTPSChecker::HTTPSChecker(sol::table data) : Checker(data)

simplomon.hh

@@ -191,6 +191,29 @@ private:
   std::set<int> d_ports;
 };
 
+class TCPPortOpenChecker : public Checker
+{
+public:
+  TCPPortOpenChecker(const std::set<std::string>& servers,
+             const std::set<int>& ports);
+  TCPPortOpenChecker(sol::table data);
+  CheckResult perform() override;
+  std::string getCheckerName() override { return "tcpportopen"; }
+  std::string getDescription() override
+  {
+    std::vector<std::string> servers;
+    for(const auto& s : d_servers) servers.push_back(s.toString());
+    return fmt::format("TCP open check, servers {}, ports {}",
+                       servers, d_ports);
+  }
+
+  
+private:
+  std::set<ComboAddress> d_servers;
+  std::set<int> d_ports;
+};
+
+
 
 class PINGChecker : public Checker
 {