[Auditbeat] fim(ebpf): enrich file events with container id (#38328)

* fim(ebpf): enrich file events with container id * fix(fim/ebpf): make container id event field ecs-compliant --------- Co-authored-by: Panos Koutsovasilis <[email protected]>
elastic · Apr 8, 2024 · 5b0b682 · 5b0b682
1 parent 0ca93e1
commit 5b0b682
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Showing 7 changed files with 61 additions and 31 deletions.
diff --git a/CHANGELOG.next.asciidoc b/CHANGELOG.next.asciidoc
@@ -149,6 +149,7 @@ https://github.com/elastic/beats/compare/v8.8.1\...main[Check the HEAD diff]
 - Add linux capabilities to processes in the system/process. {pull}37453[37453]
 - Add opt-in eBPF backend for file_integrity module. {pull}37223[37223]
 - Add process data to file events (Linux only, eBPF backend). {pull}38199[38199]
+- Add container id to file events (Linux only, eBPF backend). {pull}38328[38328]
 
 *Filebeat*
 

diff --git a/NOTICE.txt b/NOTICE.txt
@@ -12287,11 +12287,11 @@ SOFTWARE.
 
 --------------------------------------------------------------------------------
 Dependency : github.com/elastic/ebpfevents
-Version: v0.5.0
+Version: v0.6.0
 Licence type (autodetected): Apache-2.0
 --------------------------------------------------------------------------------
 
-Contents of probable licence file $GOMODCACHE/github.com/elastic/ebpfevents@v0.5.0/LICENSE.txt:
+Contents of probable licence file $GOMODCACHE/github.com/elastic/ebpfevents@v0.6.0/LICENSE.txt:
 
 The https://github.com/elastic/ebpfevents repository contains source code under
 various licenses:

diff --git a/auditbeat/module/file_integrity/event.go b/auditbeat/module/file_integrity/event.go
@@ -126,15 +126,16 @@ func (d Digest) MarshalText() ([]byte, error) { return []byte(d.String()), nil }
 
 // Event describes the filesystem change and includes metadata about the file.
 type Event struct {
-	Timestamp     time.Time           `json:"timestamp"`             // Time of event.
-	Path          string              `json:"path"`                  // The path associated with the event.
-	TargetPath    string              `json:"target_path,omitempty"` // Target path for symlinks.
-	Info          *Metadata           `json:"info"`                  // File metadata (if the file exists).
-	Source        Source              `json:"source"`                // Source of the event.
-	Action        Action              `json:"action"`                // Action (like created, updated).
-	Hashes        map[HashType]Digest `json:"hash,omitempty"`        // File hashes.
-	ParserResults mapstr.M            `json:"file,omitempty"`        // Results from running file parsers.
-	Process       *Process            `json:"process,omitempty"`     // Process data. Available only on Linux when using the eBPF backend.
+	Timestamp     time.Time           `json:"timestamp"`              // Time of event.
+	Path          string              `json:"path"`                   // The path associated with the event.
+	TargetPath    string              `json:"target_path,omitempty"`  // Target path for symlinks.
+	Info          *Metadata           `json:"info"`                   // File metadata (if the file exists).
+	Source        Source              `json:"source"`                 // Source of the event.
+	Action        Action              `json:"action"`                 // Action (like created, updated).
+	Hashes        map[HashType]Digest `json:"hash,omitempty"`         // File hashes.
+	ParserResults mapstr.M            `json:"file,omitempty"`         // Results from running file parsers.
+	Process       *Process            `json:"process,omitempty"`      // Process data. Available only on Linux when using the eBPF backend.
+	ContainerID   string              `json:"container_id,omitempty"` // Unique container ID. Available only on Linux when using the eBPF backend.
 
 	// Metadata
 	rtt        time.Duration // Time taken to collect the info.
@@ -400,6 +401,10 @@ func buildMetricbeatEvent(e *Event, existedBefore bool) mb.Event {
 		out.MetricSetFields.Put("process", process)
 	}
 
+	if e.ContainerID != "" {
+		out.MetricSetFields.Put("container.id", e.ContainerID)
+	}
+
 	if len(e.Hashes) > 0 {
 		hashes := make(mapstr.M, len(e.Hashes))
 		for hashType, digest := range e.Hashes {

diff --git a/auditbeat/module/file_integrity/event_linux.go b/auditbeat/module/file_integrity/event_linux.go
@@ -23,13 +23,17 @@ import (
 	"os"
 	"os/user"
 	"path/filepath"
+	"regexp"
 	"strconv"
 	"time"
 
 	"github.com/elastic/beats/v7/libbeat/ebpf/sys"
 	"github.com/elastic/ebpfevents"
 )
 
+// cgroupRegex captures 64-character lowercase hexadecimal container IDs found in cgroup paths.
+var cgroupRegex = regexp.MustCompile(`[-/]([0-9a-f]{64})(\.scope)?$`)
+
 // NewEventFromEbpfEvent creates a new Event from an ebpfevents.Event.
 func NewEventFromEbpfEvent(
 	ee ebpfevents.Event,
@@ -39,12 +43,12 @@ func NewEventFromEbpfEvent(
 	isExcludedPath func(string) bool,
 ) (Event, bool) {
 	var (
-		path, target string
-		action       Action
-		metadata     Metadata
-		process      Process
-		err          error
-		errors       []error
+		path, target, cgroupPath string
+		action                   Action
+		metadata                 Metadata
+		process                  Process
+		err                      error
+		errors                   []error
 	)
 	switch ee.Type {
 	case ebpfevents.EventTypeFileCreate:
@@ -67,6 +71,8 @@ func NewEventFromEbpfEvent(
 		if err != nil {
 			errors = append(errors, err)
 		}
+
+		cgroupPath = fileCreateEvent.CgroupPath
 	case ebpfevents.EventTypeFileRename:
 		action = Moved
 
@@ -87,6 +93,8 @@ func NewEventFromEbpfEvent(
 		if err != nil {
 			errors = append(errors, err)
 		}
+
+		cgroupPath = fileRenameEvent.CgroupPath
 	case ebpfevents.EventTypeFileDelete:
 		action = Deleted
 
@@ -102,6 +110,8 @@ func NewEventFromEbpfEvent(
 		if err != nil {
 			errors = append(errors, err)
 		}
+
+		cgroupPath = fileDeleteEvent.CgroupPath
 	case ebpfevents.EventTypeFileModify:
 		fileModifyEvent := ee.Body.(*ebpfevents.FileModify)
 
@@ -128,17 +138,20 @@ func NewEventFromEbpfEvent(
 		if err != nil {
 			errors = append(errors, err)
 		}
+
+		cgroupPath = fileModifyEvent.CgroupPath
 	}
 
 	event := Event{
-		Timestamp:  time.Now().UTC(),
-		Path:       path,
-		TargetPath: target,
-		Info:       &metadata,
-		Source:     SourceEBPF,
-		Action:     action,
-		Process:    &process,
-		errors:     errors,
+		Timestamp:   time.Now().UTC(),
+		Path:        path,
+		TargetPath:  target,
+		Info:        &metadata,
+		Source:      SourceEBPF,
+		Action:      action,
+		Process:     &process,
+		ContainerID: containerIDFromCgroupPath(cgroupPath),
+		errors:      errors,
 	}
 
 	if event.Action == Deleted {
@@ -158,6 +171,14 @@ func NewEventFromEbpfEvent(
 	return event, true
 }
 
+func containerIDFromCgroupPath(path string) string {
+	matches := cgroupRegex.FindStringSubmatch(path)
+	if len(matches) > 1 {
+		return matches[1]
+	}
+	return ""
+}
+
 func metadataFromFileCreate(evt *ebpfevents.FileCreate) (Metadata, error) {
 	var md Metadata
 	fillExtendedAttributes(&md, evt.Path)

diff --git a/auditbeat/module/file_integrity/event_linux_test.go b/auditbeat/module/file_integrity/event_linux_test.go
@@ -29,6 +29,7 @@ import (
 )
 
 func TestNewEventFromEbpfEvent(t *testing.T) {
+	containerID := "d12fe576354a1805165303a4e34a69e5fe8db791ceb7e545f17811d1fbfba68f"
 	ebpfEvent := ebpfevents.Event{
 		Header: ebpfevents.Header{
 			Type: ebpfevents.EventTypeFileCreate,
@@ -52,6 +53,7 @@ func TestNewEventFromEbpfEvent(t *testing.T) {
 				Suid: 5,
 				Sgid: 6,
 			},
+			CgroupPath: "/kubepods.slice/kubepods-burstable.slice/kubepods-burstable-pod123.slice/cri-containerd-" + containerID + ".scope",
 		},
 	}
 	event, ok := NewEventFromEbpfEvent(
@@ -72,9 +74,10 @@ func TestNewEventFromEbpfEvent(t *testing.T) {
 			Group: event.Info.Group,
 			Mode:  os.FileMode(0o644),
 		},
-		Process: event.Process, // 1:1 copy this as it changes on every machine
-		Source:  SourceEBPF,
-		errors:  nil,
+		Process:     event.Process, // 1:1 copy this as it changes on every machine
+		ContainerID: containerID,
+		Source:      SourceEBPF,
+		errors:      nil,
 	}
 	event.Timestamp = expectedEvent.Timestamp
 

diff --git a/go.mod b/go.mod
@@ -201,7 +201,7 @@ require (
 	github.com/aws/smithy-go v1.13.5
 	github.com/awslabs/kinesis-aggregation/go/v2 v2.0.0-20220623125934-28468a6701b5
 	github.com/elastic/bayeux v1.0.5
-	github.com/elastic/ebpfevents v0.5.0
+	github.com/elastic/ebpfevents v0.6.0
 	github.com/elastic/elastic-agent-autodiscover v0.6.8
 	github.com/elastic/elastic-agent-libs v0.7.5
 	github.com/elastic/elastic-agent-shipper-client v0.5.1-0.20230228231646-f04347b666f3

diff --git a/go.sum b/go.sum
@@ -672,8 +672,8 @@ github.com/elastic/bayeux v1.0.5 h1:UceFq01ipmT3S8DzFK+uVAkbCdiPR0Bqei8qIGmUeY0=
 github.com/elastic/bayeux v1.0.5/go.mod h1:CSI4iP7qeo5MMlkznGvYKftp8M7qqP/3nzmVZoXHY68=
 github.com/elastic/dhcp v0.0.0-20200227161230-57ec251c7eb3 h1:lnDkqiRFKm0rxdljqrj3lotWinO9+jFmeDXIC4gvIQs=
 github.com/elastic/dhcp v0.0.0-20200227161230-57ec251c7eb3/go.mod h1:aPqzac6AYkipvp4hufTyMj5PDIphF3+At8zr7r51xjY=
-github.com/elastic/ebpfevents v0.5.0 h1:QkyMAYWo3fXFbYtXAXU8sZu2SQ4LXVYC6gLXIWXy02E=
-github.com/elastic/ebpfevents v0.5.0/go.mod h1:ESG9gw7N+n5yCCMgdg1IIJENKWSmX7+X0Fi9GUs9nvU=
+github.com/elastic/ebpfevents v0.6.0 h1:BrL3m7JFK7U6h2jkbk3xAWWs//IZnugCHEDds5u2v68=
+github.com/elastic/ebpfevents v0.6.0/go.mod h1:ESG9gw7N+n5yCCMgdg1IIJENKWSmX7+X0Fi9GUs9nvU=
 github.com/elastic/elastic-agent-autodiscover v0.6.8 h1:BSXz+QwjZAEt08G+T3GDGl14Bh9a6zD8luNCvZut/b8=
 github.com/elastic/elastic-agent-autodiscover v0.6.8/go.mod h1:hFeFqneS2r4jD0/QzGkrNk0YVdN0JGh7lCWdsH7zcI4=
 github.com/elastic/elastic-agent-client/v7 v7.8.1 h1:J9wZc/0mUvSEok0X5iR5+n60Jgb+AWooKddb3XgPWqM=