Add an introspection endpoint for container metadata

collector/lib/CollectorConfig.cpp

@@ -51,6 +51,8 @@ BoolEnvVar enable_runtime_filters("ROX_COLLECTOR_RUNTIME_FILTERS_ENABLED", false
 BoolEnvVar use_docker_ce("ROX_COLLECTOR_CE_USE_DOCKER", false);
 BoolEnvVar use_podman_ce("ROX_COLLECTOR_CE_USE_PODMAN", false);
 
+BoolEnvVar enable_introspection("ROX_COLLECTOR_INTROSPECTION_ENABLE", false);
+
 }  // namespace
 
 constexpr bool CollectorConfig::kTurnOffScrape;
@@ -79,6 +81,7 @@ void CollectorConfig::InitCollectorConfig(CollectorArgs* args) {
   enable_runtime_filters_ = enable_runtime_filters.value();
   use_docker_ce_ = use_docker_ce.value();
   use_podman_ce_ = use_podman_ce.value();
+  enable_introspection_ = enable_introspection.value();
 
   for (const auto& syscall : kSyscalls) {
     syscalls_.push_back(syscall);

collector/lib/CollectorConfig.h

@@ -78,6 +78,7 @@ class CollectorConfig {
   bool EnableRuntimeFilters() const { return enable_runtime_filters_; }
   bool UseDockerCe() const { return use_docker_ce_; }
   bool UsePodmanCe() const { return use_podman_ce_; }
+  bool IsIntrospectionEnabled() const { return enable_introspection_; }
   const std::vector<double>& GetConnectionStatsQuantiles() const { return connection_stats_quantiles_; }
   double GetConnectionStatsError() const { return connection_stats_error_; }
   unsigned int GetConnectionStatsWindow() const { return connection_stats_window_; }
@@ -113,6 +114,7 @@ class CollectorConfig {
   bool enable_runtime_filters_;
   bool use_docker_ce_;
   bool use_podman_ce_;
+  bool enable_introspection_;
   std::vector<double> connection_stats_quantiles_;
   double connection_stats_error_;
   unsigned int connection_stats_window_;

collector/lib/CollectorService.cpp

@@ -1,5 +1,7 @@
 #include "CollectorService.h"
 
+#include "ContainerInfoInspector.h"
+
 extern "C" {
 #include <signal.h>
 }
@@ -58,6 +60,8 @@ void CollectorService::RunForever() {
 
   std::unique_ptr<NetworkStatusNotifier> net_status_notifier;
 
+  std::unique_ptr<ContainerInfoInspector> container_info_inspector;
+
   CLOG(INFO) << "Network scrape interval set to " << config_.ScrapeInterval() << " seconds";
 
   if (config_.grpc_channel) {
@@ -99,6 +103,11 @@ void CollectorService::RunForever() {
     CLOG(FATAL) << "Unable to start collector stats exporter";
   }
 
+  if (config_.IsIntrospectionEnabled()) {
+    container_info_inspector = std::make_unique<ContainerInfoInspector>(system_inspector_.GetContainerMetadataInspector());
+    server.addHandler(container_info_inspector->kBaseRoute, container_info_inspector.get());
+  }
+
   system_inspector_.Init(config_, conn_tracker);
   system_inspector_.Start();
 

collector/lib/ContainerInfoInspector.cpp

@@ -0,0 +1,34 @@
+#include "ContainerInfoInspector.h"
+
+#include <civetweb.h>
+#include <string>
+#include <string_view>
+
+namespace collector {
+const char* const ContainerInfoInspector::kBaseRoute = "/state/containers/";
+
+bool ContainerInfoInspector::handleGet(CivetServer* server, struct mg_connection* conn) {
+  const mg_request_info* req_info = mg_get_request_info(conn);
+  if (req_info == nullptr) {
+    return ServerError(conn, "unable to read request");
+  }
+
+  std::string_view url = req_info->local_uri;
+  std::string container_id(url.substr(url.rfind('/') + 1));
+
+  if (container_id.length() != 12) {
+    return ClientError(conn, "invalid container ID");
+  }
+
+  Json::Value root;
+
+  root["container_id"] = container_id;
+  root["namespace"] = std::string(container_metadata_inspector_->GetNamespace(container_id));
+
+  mg_printf(conn, "HTTP/1.1 200 OK\r\nContent-Type: application/json\r\nConnection: close\r\n\r\n");
+  mg_printf(conn, "%s\r\n", writer_.write(root).c_str());
+
+  return true;
+}
+
+}  // namespace collector

collector/lib/ContainerInfoInspector.h

@@ -0,0 +1,34 @@
+#ifndef _CONTAINER_INFO_INSPECTOR_
+#define _CONTAINER_INFO_INSPECTOR_
+
+#include <CivetServer.h>
+#include <civetweb.h>
+#include <memory>
+#include <string>
+#include <unordered_map>
+
+#include "ContainerMetadata.h"
+#include "IntrospectionEndpoint.h"
+#include "json/writer.h"
+
+namespace collector {
+
+using QueryParams = std::unordered_map<std::string, std::string>;
+
+class ContainerInfoInspector : public IntrospectionEndpoint {
+ public:
+  static const char* const kBaseRoute;
+
+  ContainerInfoInspector(const std::shared_ptr<ContainerMetadata>& cmi) : container_metadata_inspector_(cmi) {}
+
+  // implementation of CivetHandler
+  bool handleGet(CivetServer* server, struct mg_connection* conn) override;
+
+ private:
+  std::shared_ptr<ContainerMetadata> container_metadata_inspector_;
+  Json::FastWriter writer_;
+};
+
+}  // namespace collector
+
+#endif  //_CONTAINER_INFO_INSPECTOR_

collector/lib/IntrospectionEndpoint.cpp

@@ -0,0 +1,33 @@
+#include "IntrospectionEndpoint.h"
+
+#include <sstream>
+
+namespace collector {
+
+QueryParams IntrospectionEndpoint::ParseParameters(const char* queryString) {
+  QueryParams params;
+
+  if (queryString == nullptr) {
+    return params;
+  }
+
+  std::stringstream query_stringstream(queryString);
+  while (query_stringstream.good()) {
+    std::string statement;
+
+    std::getline(query_stringstream, statement, '&');
+
+    size_t equal = statement.find('=');
+
+    if (equal != std::string::npos) {
+      params[statement.substr(0, equal)] = statement.substr(equal + 1);
+    }
+  }
+  return params;
+}
+
+std::optional<std::string> IntrospectionEndpoint::GetParameter(const QueryParams& params, const std::string& paramName) {
+  return params.count(paramName) != 0 ? std::make_optional(params.at(paramName)) : std::nullopt;
+}
+
+}  // namespace collector

collector/lib/IntrospectionEndpoint.h

@@ -0,0 +1,27 @@
+#ifndef _INTROSPECTION_ENDPOINT_
+#define _INTROSPECTION_ENDPOINT_
+
+#include <CivetServer.h>
+#include <optional>
+#include <unordered_map>
+
+namespace collector {
+
+using QueryParams = std::unordered_map<std::string, std::string>;
+
+class IntrospectionEndpoint : public CivetHandler {
+ protected:
+  static QueryParams ParseParameters(const char* queryString);
+  static std::optional<std::string> GetParameter(const QueryParams& params, const std::string& paramName);
+
+  static bool ServerError(struct mg_connection* conn, const char* err) {
+    return mg_send_http_error(conn, 500, err) >= 0;
+  }
+  static bool ClientError(struct mg_connection* conn, const char* err) {
+    return mg_send_http_error(conn, 400, err) >= 0;
+  }
+};
+
+}  // namespace collector
+
+#endif  // _INTROSPECTION_ENDPOINT_

collector/lib/system-inspector/Service.cpp

@@ -14,6 +14,7 @@
 #include "CollectorException.h"
 #include "CollectorStats.h"
 #include "ContainerEngine.h"
+#include "ContainerMetadata.h"
 #include "EventNames.h"
 #include "HostInfo.h"
 #include "KernelDriver.h"
@@ -89,6 +90,8 @@ bool Service::InitKernel(const CollectorConfig& config, const DriverCandidate& c
       inspector_->get_parser()->set_track_connection_status(true);
     }
 
+    container_metadata_inspector_.reset(new ContainerMetadata(inspector_.get()));
+
     if (config.EnableRuntimeFilters()) {
       uint64_t mask = 1 << CT_CRI |
                       1 << CT_CRIO |

collector/lib/system-inspector/Service.h

@@ -11,6 +11,7 @@
 
 #include "libsinsp/sinsp.h"
 
+#include "ContainerMetadata.h"
 #include "Control.h"
 #include "DriverCandidates.h"
 #include "SignalHandler.h"
@@ -44,6 +45,8 @@ class Service : public SystemInspector {
 
   void GetProcessInformation(uint64_t pid, ProcessInfoCallbackRef callback);
 
+  std::shared_ptr<ContainerMetadata> GetContainerMetadataInspector() { return container_metadata_inspector_; };
+
  private:
   FRIEND_TEST(SystemInspectorServiceTest, FilterEvent);
 
@@ -69,6 +72,7 @@ class Service : public SystemInspector {
 
   mutable std::mutex libsinsp_mutex_;
   std::unique_ptr<sinsp> inspector_;
+  std::shared_ptr<ContainerMetadata> container_metadata_inspector_;
   std::unique_ptr<sinsp_evt_formatter> default_formatter_;
   std::unique_ptr<ISignalServiceClient> signal_client_;
   std::vector<SignalHandlerEntry> signal_handlers_;