[Elastic Agent] Add fleet.host.id for sending to endpoint. (elastic#2…

…1042)

* Add fleet.host.id for sending to endpoint.

* Add changelog entry.

(cherry picked from commit b67442e)

x-pack/elastic-agent/CHANGELOG.next.asciidoc

@@ -19,3 +19,4 @@
 - Users of the Docker image can now pass `FLEET_ENROLL_INSECURE=1` to include the `--insecure` flag with the `elastic-agent enroll` command {issue}20312[20312] {pull}20713[20713]
 - Add support for dynamic inputs with providers and `{{variable|"default"}}` substitution. {pull}20839[20839]
 - Add support for EQL based condition on inputs {pull}20994[20994]
+- Send `fleet.host.id` to Endpoint Security {pull}21042[21042]

x-pack/elastic-agent/pkg/agent/application/fleet_decorator.go

@@ -7,12 +7,14 @@ package application
 import (
 	"fmt"
 
+	"github.com/elastic/go-sysinfo/types"
+
 	"github.com/elastic/beats/v7/x-pack/elastic-agent/pkg/agent/transpiler"
 	"github.com/elastic/beats/v7/x-pack/elastic-agent/pkg/config"
 	"github.com/elastic/beats/v7/x-pack/elastic-agent/pkg/core/logger"
 )
 
-func injectFleet(cfg *config.Config) func(*logger.Logger, *transpiler.AST) error {
+func injectFleet(cfg *config.Config, hostInfo types.HostInfo) func(*logger.Logger, *transpiler.AST) error {
 	return func(logger *logger.Logger, rootAst *transpiler.AST) error {
 		config, err := cfg.ToMapStr()
 		if err != nil {
@@ -37,7 +39,11 @@ func injectFleet(cfg *config.Config) func(*logger.Logger, *transpiler.AST) error
 			return fmt.Errorf("failed to get agent key from fleet config")
 		}
 
-		fleet := transpiler.NewDict([]transpiler.Node{agent, token, kbn})
+		host := transpiler.NewKey("host", transpiler.NewDict([]transpiler.Node{
+			transpiler.NewKey("id", transpiler.NewStrVal(hostInfo.UniqueID)),
+		}))
+
+		fleet := transpiler.NewDict([]transpiler.Node{agent, token, kbn, host})
 		err = transpiler.Insert(rootAst, fleet, "fleet")
 		if err != nil {
 			return err

x-pack/elastic-agent/pkg/agent/application/managed_mode.go

@@ -11,6 +11,8 @@ import (
 	"net/http"
 	"net/url"
 
+	"github.com/elastic/go-sysinfo"
+
 	"github.com/elastic/beats/v7/x-pack/elastic-agent/pkg/agent/application/filters"
 	"github.com/elastic/beats/v7/x-pack/elastic-agent/pkg/agent/application/info"
 	"github.com/elastic/beats/v7/x-pack/elastic-agent/pkg/agent/configuration"
@@ -117,6 +119,13 @@ func newManaged(
 			errors.M(errors.MetaKeyURI, cfg.Fleet.Kibana.Host))
 	}
 
+	sysInfo, err := sysinfo.Host()
+	if err != nil {
+		return nil, errors.New(err,
+			"fail to get system information",
+			errors.TypeUnexpected)
+	}
+
 	managedApplication := &Managed{
 		log:       log,
 		agentInfo: agentInfo,
@@ -164,7 +173,7 @@ func newManaged(
 		router,
 		&configModifiers{
 			Decorators: []decoratorFunc{injectMonitoring},
-			Filters:    []filterFunc{filters.StreamChecker, injectFleet(config)},
+			Filters:    []filterFunc{filters.StreamChecker, injectFleet(config, sysInfo.Info())},
 		},
 		monitor,
 	)

x-pack/elastic-agent/pkg/agent/program/testdata/endpoint_basic-endpoint-security.yml

@@ -2,6 +2,8 @@ revision: 5
 fleet:
   agent:
     id: fleet-agent-id
+  host:
+    id: host-agent-id
   api:
     access_api_key: VuaCfGcBCdbkQm-e5aOx:ui2lp2axTNmsyakw9tvNnw
     kibana:

x-pack/elastic-agent/pkg/agent/program/testdata/endpoint_basic.yml

@@ -3,6 +3,8 @@ name: Endpoint Host
 fleet:
   agent:
     id: fleet-agent-id
+  host:
+    id: host-agent-id
   access_api_key: VuaCfGcBCdbkQm-e5aOx:ui2lp2axTNmsyakw9tvNnw
   kibana:
     protocol: https