fix checking host

Author: aphralG

internal/datasource/config/nginx_config_parser.go

@@ -257,7 +257,13 @@ func (ncp *NginxConfigParser) findValidSysLogServers(sysLogServers []string) []s
 	for i := range sysLogServers {
 		matches := re.FindStringSubmatch(sysLogServers[i])
 		if len(matches) > 1 {
-			if strings.HasPrefix(matches[1], "localhost") || strings.HasPrefix(matches[1], "127.0.0.1") {
+			host, _, err := net.SplitHostPort(matches[1])
+			if err != nil {
+				continue
+			}
+
+			ip := net.ParseIP(host)
+			if ip.IsLoopback() || strings.EqualFold(host, "localhost") {
 				servers = append(servers, matches[1])
 			}
 		}

internal/datasource/config/nginx_config_parser_test.go

@@ -688,8 +688,9 @@ func TestNginxConfigParser_findValidSysLogServers(t *testing.T) {
 		"app_protect_security_log", "/etc/app_protect/conf/log_default1.json", "syslog:server=my.domain.com:1517",
 		"app_protect_security_log", "/etc/app_protect/conf/log_default2.json", "syslog:server=127.0.0.1:1515",
 		"app_protect_security_log", "/etc/app_protect/conf/log_default3.json", "syslog:server=localhost:1516",
+		"app_protect_security_log\", \"/etc/app_protect/conf/log_default3.json\", \"syslog:server=127.255.255.255:1517",
 	}
-	expected := []string{"127.0.0.1:1515", "localhost:1516"}
+	expected := []string{"127.0.0.1:1515", "localhost:1516", "127.255.255.255:1517"}
 	ncp := NewNginxConfigParser(types.AgentConfig())
 	result := ncp.findValidSysLogServers(servers)