[Filebeat] Add parse_aws_vpc_flow_log processor

CHANGELOG.next.asciidoc

@@ -156,6 +156,7 @@ https://github.com/elastic/beats/compare/v8.2.0\...main[Check the HEAD diff]
 - Improve httpjson documentation for split processor. {pull}33473[33473]
 - Added separation of transform context object inside httpjson. Introduced new clause `.parent_last_response.*` {pull}33499[33499]
 - Cloud Foundry input uses server-side filtering when retrieving logs. {pull}33456[33456]
+- Add `parse_aws_vpc_flow_log` processor. {pull}33656[33656]
 
 *Auditbeat*
 

auditbeat/docs/index.asciidoc

@@ -22,6 +22,7 @@ include::{asciidoc-dir}/../../shared/attributes.asciidoc[]
 :linux_os:
 :no_decode_cef_processor:
 :no_decode_csv_fields_processor:
+:no_parse_aws_vpc_flow_log_processor:
 :no_script_processor:
 :no_timestamp_processor:
 

heartbeat/docs/index.asciidoc

@@ -24,6 +24,7 @@ include::{asciidoc-dir}/../../shared/attributes.asciidoc[]
 :no_dashboards:
 :no_decode_cef_processor:
 :no_decode_csv_fields_processor:
+:no_parse_aws_vpc_flow_log_processor:
 :no_timestamp_processor:
 
 include::{libbeat-dir}/shared-beats-attributes.asciidoc[]

libbeat/docs/processors-list.asciidoc

@@ -104,6 +104,9 @@ endif::[]
 ifndef::no_rename_processor[]
 * <<rename-fields,`rename`>>
 endif::[]
+ifndef::no_parse_aws_vpc_flow_log_processor[]
+* <<processor-parse-aws-vpc-flow-log, `parse_aws_vpc_flow_log`>>
+endif::[]
 ifndef::no_script_processor[]
 * <<processor-script,`script`>>
 endif::[]
@@ -231,6 +234,9 @@ endif::[]
 ifndef::no_rename_processor[]
 include::{libbeat-processors-dir}/actions/docs/rename.asciidoc[]
 endif::[]
+ifndef::no_parse_aws_vpc_flow_log_processor[]
+include::{x-filebeat-processors-dir}/aws_vpcflow/docs/parse_aws_vpc_flow_log.asciidoc[]
+endif::[]
 ifndef::no_script_processor[]
 include::{libbeat-processors-dir}/script/docs/script.asciidoc[]
 endif::[]

metricbeat/docs/index.asciidoc

@@ -28,6 +28,7 @@ include::{asciidoc-dir}/../../shared/attributes.asciidoc[]
 :win_os:
 :no_decode_cef_processor:
 :no_decode_csv_fields_processor:
+:no_parse_aws_vpc_flow_log_processor:
 :no_timestamp_processor:
 
 :kubernetes_default_indexers: {docdir}/kubernetes-default-indexers-matchers.asciidoc

packetbeat/docs/index.asciidoc

@@ -24,6 +24,7 @@ include::{asciidoc-dir}/../../shared/attributes.asciidoc[]
 :win_os:
 :no_decode_cef_processor:
 :no_decode_csv_fields_processor:
+:no_parse_aws_vpc_flow_log_processor:
 :no_script_processor:
 :no_timestamp_processor:
 

winlogbeat/docs/index.asciidoc

@@ -20,6 +20,7 @@ include::{asciidoc-dir}/../../shared/attributes.asciidoc[]
 :win_only:
 :no_decode_cef_processor:
 :no_decode_csv_fields_processor:
+:no_parse_aws_vpc_flow_log_processor:
 :include_translate_sid_processor:
 :export_pipeline:
 

x-pack/filebeat/processors/aws_vpcflow/config.go

@@ -0,0 +1,101 @@
+// Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+// or more contributor license agreements. Licensed under the Elastic License;
+// you may not use this file except in compliance with the Elastic License.
+
+package aws_vpcflow
+
+import (
+	"errors"
+	"fmt"
+	"strings"
+)
+
+// mode represents the processing mode (original, ecs, ecs_and_original).
+type mode uint8
+
+const (
+	originalMode       mode = iota // originalMode generates the fields specified in the format string.
+	ecsMode                        // ecsMode maps the original fields to ECS and removes the original field if it was mapped.
+	ecsAndOriginalMode             // ecsAndOriginalMode maps the original fields to ECS and retains all the original fields.
+)
+
+var modeStrings = map[mode]string{
+	originalMode:       "original",
+	ecsMode:            "ecs",
+	ecsAndOriginalMode: "ecs_and_original",
+}
+
+func (m *mode) Unpack(s string) error {
+	for modeConst, modeStr := range modeStrings {
+		if strings.EqualFold(modeStr, s) {
+			*m = modeConst
+			return nil
+		}
+	}
+	return fmt.Errorf("invalid mode type <%v> for "+procName, s)
+}
+
+func (m *mode) UnmarshalYAML(unmarshal func(interface{}) error) error {
+	var str string
+	if err := unmarshal(&str); err != nil {
+		return err
+	}
+	return m.Unpack(str)
+}
+
+func (m *mode) String() string {
+	if s, found := modeStrings[*m]; found {
+		return s
+	}
+	return "unknown mode"
+}
+
+// config contains the configuration options for the processor.
+type config struct {
+	Format        string `config:"format" validate:"required"` // VPC flow log format.
+	Mode          mode   `config:"mode"`                       // Mode controls what fields are generated.
+	Field         string `config:"field"`                      // Source field containing the VPC flow log message.
+	TargetField   string `config:"target_field"`               // Target field for the VPC flow log object. This applies only to the original VPC flow log fields. ECS fields are written to the standard location.
+	IgnoreMissing bool   `config:"ignore_missing"`             // Ignore missing source field.
+	IgnoreFailure bool   `config:"ignore_failure"`             // Ignore failures while parsing and transforming the flow log message.
+	ID            string `config:"id"`                         // Instance ID for debugging purposes.
+}
+
+// Validate validates the config settings. It returns an error if the format
+// string is invalid.
+func (c *config) Validate() error {
+	_, err := parseFormat(c.Format)
+	return err
+}
+
+func defaultConfig() config {
+	return config{
+		Mode:        ecsMode,
+		Field:       "message",
+		TargetField: "aws.vpcflow",
+	}
+}
+
+// parseFormat parses VPC flow log format string and returns an ordered list of
+// the expected fields.
+func parseFormat(format string) ([]vpcFlowField, error) {
+	tokens := strings.Fields(format)
+	if len(tokens) == 0 {
+		return nil, errors.New("format must contain at lease one field")
+	}
+
+	fields := make([]vpcFlowField, 0, len(tokens))
+	for _, token := range tokens {
+		// Elastic uses underscores in field names rather than dashes.
+		underscoreToken := strings.ReplaceAll(token, "-", "_")
+
+		field, found := nameToFieldMap[underscoreToken]
+		if !found {
+			return nil, fmt.Errorf("unknown field %q", token)
+		}
+
+		fields = append(fields, field)
+	}
+
+	return fields, nil
+}

x-pack/filebeat/processors/aws_vpcflow/config_test.go

@@ -0,0 +1,75 @@
+// Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+// or more contributor license agreements. Licensed under the Elastic License;
+// you may not use this file except in compliance with the Elastic License.
+
+package aws_vpcflow
+
+import (
+	"strconv"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+
+	conf "github.com/elastic/elastic-agent-libs/config"
+)
+
+func TestConfigUnpack(t *testing.T) {
+	testCases := []struct {
+		yamlConfig string
+		error      bool
+	}{
+		{
+			yamlConfig: `
+---
+mode: ecs_and_original
+id: us-east-vpcflow
+format: instance-id interface-id srcaddr dstaddr pkt-srcaddr pkt-dstaddr
+`,
+		},
+		{
+			yamlConfig: `
+---
+mode: original
+format: version interface-id account-id vpc-id subnet-id instance-id srcaddr dstaddr srcport dstport protocol tcp-flags type pkt-srcaddr pkt-dstaddr action log-status
+`,
+		},
+		{
+			yamlConfig: `
+---
+mode: ecs
+format: version srcaddr dstaddr srcport dstport protocol start end type packets bytes account-id vpc-id subnet-id instance-id interface-id region az-id sublocation-type sublocation-id action tcp-flags pkt-srcaddr pkt-dstaddr pkt-src-aws-service pkt-dst-aws-service traffic-path flow-direction log-status
+`,
+		},
+		{
+			yamlConfig: `
+---
+mode: ecs
+format: version srcaddr dstaddr srcport dstport protocol start end type packets bytes account-id vpc-id subnet-id instance-id interface-id region az-id sublocation-type sublocation-id action tcp-flags pkt-srcaddr pkt-dstaddr pkt-src-aws-service pkt-dst-aws-service traffic-path flow-direction log-status
+`,
+		},
+		{
+			error: true,
+			yamlConfig: `
+---
+mode: invalid
+format: version
+`,
+		},
+	}
+
+	for i, tc := range testCases {
+		tc := tc
+		t.Run(strconv.Itoa(i), func(t *testing.T) {
+			rawConfig := conf.MustNewConfigFrom(tc.yamlConfig)
+
+			c := defaultConfig()
+			err := rawConfig.Unpack(&c)
+			if tc.error {
+				t.Log("Error:", err)
+				require.Error(t, err)
+				return
+			}
+			require.NoError(t, err)
+		})
+	}
+}