Use gosmi for SNMP traps (#9343)

Use gosmi for snmp_trap plugin

Co-authored-by: Logan McNaughton <logan@bacoosta.com>
Co-authored-by: reimda <reimda@users.noreply.github.com>

docs/LICENSE_OF_DEPENDENCIES.md

@@ -19,6 +19,7 @@ following works:
 - github.com/Shopify/sarama [MIT License](https://github.com/Shopify/sarama/blob/master/LICENSE)
 - github.com/StackExchange/wmi [MIT License](https://github.com/StackExchange/wmi/blob/master/LICENSE)
 - github.com/aerospike/aerospike-client-go [Apache License 2.0](https://github.com/aerospike/aerospike-client-go/blob/master/LICENSE)
+- github.com/alecthomas/participle [MIT License](https://github.com/alecthomas/participle/blob/master/COPYING)
 - github.com/alecthomas/units [MIT License](https://github.com/alecthomas/units/blob/master/COPYING)
 - github.com/aliyun/alibaba-cloud-sdk-go [Apache License 2.0](https://github.com/aliyun/alibaba-cloud-sdk-go/blob/master/LICENSE)
 - github.com/amir/raidman [The Unlicense](https://github.com/amir/raidman/blob/master/UNLICENSE)
@@ -188,6 +189,7 @@ following works:
 - github.com/signalfx/golib [Apache License 2.0](https://github.com/signalfx/golib/blob/master/LICENSE)
 - github.com/signalfx/sapm-proto [Apache License 2.0](https://github.com/signalfx/sapm-proto/blob/master/LICENSE)
 - github.com/sirupsen/logrus [MIT License](https://github.com/sirupsen/logrus/blob/master/LICENSE)
+- github.com/sleepinggenius2/gosmi [MIT License](https://github.com/sleepinggenius2/gosmi/blob/master/LICENSE)
 - github.com/snowflakedb/gosnowflake [Apache License 2.0](https://github.com/snowflakedb/gosnowflake/blob/master/LICENSE)
 - github.com/streadway/amqp [BSD 2-Clause "Simplified" License](https://github.com/streadway/amqp/blob/master/LICENSE)
 - github.com/stretchr/objx [MIT License](https://github.com/stretchr/objx/blob/master/LICENSE)

go.mod

@@ -112,6 +112,7 @@ require (
 	github.com/shopspring/decimal v0.0.0-20200105231215-408a2507e114 // indirect
 	github.com/signalfx/golib/v3 v3.3.0
 	github.com/sirupsen/logrus v1.7.0
+	github.com/sleepinggenius2/gosmi v0.4.3
 	github.com/snowflakedb/gosnowflake v1.5.0
 	github.com/streadway/amqp v0.0.0-20190827072141-edfb9018d271
 	github.com/stretchr/testify v1.7.0

go.sum

@@ -164,6 +164,12 @@ github.com/aerospike/aerospike-client-go v1.27.0/go.mod h1:zj8LBEnWBDOVEIJt8LvaR
 github.com/afex/hystrix-go v0.0.0-20180502004556-fa1af6a1f4f5/go.mod h1:SkGFH1ia65gfNATL8TAiHDNxPzPdmEL5uirI2Uyuz6c=
 github.com/agnivade/levenshtein v1.0.1/go.mod h1:CURSv5d9Uaml+FovSIICkLbAUZ9S4RqaHDIsdSBg7lM=
 github.com/ajstarks/svgo v0.0.0-20180226025133-644b8db467af/go.mod h1:K08gAheRH3/J6wwsYMMT4xOr94bZjxIelGM0+d/wbFw=
+github.com/alecthomas/go-thrift v0.0.0-20170109061633-7914173639b2/go.mod h1:CxCgO+NdpMdi9SsTlGbc0W+/UNxO3I0AabOEJZ3w61w=
+github.com/alecthomas/kong v0.2.1/go.mod h1:+inYUSluD+p4L8KdviBSgzcqEjUQOfC5fQDRFuc36lI=
+github.com/alecthomas/participle v0.4.1 h1:P2PJWzwrSpuCWXKnzqvw0b0phSfH1kJo4p2HvLynVsI=
+github.com/alecthomas/participle v0.4.1/go.mod h1:T8u4bQOSMwrkTWOSyt8/jSFPEnRtd0FKFMjVfYBlqPs=
+github.com/alecthomas/repr v0.0.0-20181024024818-d37bc2a10ba1/go.mod h1:xTS7Pm1pD1mvyM075QCDSRqH6qRLXylzS24ZTpRiSzQ=
+github.com/alecthomas/repr v0.0.0-20210301060118-828286944d6a/go.mod h1:2kn6fqh/zIyPLmm3ugklbEi5hg5wS435eygvNfaDQL8=
 github.com/alecthomas/template v0.0.0-20160405071501-a0175ee3bccc/go.mod h1:LOuyumcjzFXgccqObfd/Ljyb9UuFJ6TxHnclSeseNhc=
 github.com/alecthomas/template v0.0.0-20190718012654-fb15b899a751/go.mod h1:LOuyumcjzFXgccqObfd/Ljyb9UuFJ6TxHnclSeseNhc=
 github.com/alecthomas/units v0.0.0-20151022065526-2efee857e7cf/go.mod h1:ybxpYRFXyAe+OPACYpWeL0wqObRcbAqCMya13uyzqw0=
@@ -1370,6 +1376,8 @@ github.com/sirupsen/logrus v1.6.0/go.mod h1:7uNnSEd1DgxDLC74fIahvMZmmYsHGZGEOFrf
 github.com/sirupsen/logrus v1.6.0/go.mod h1:7uNnSEd1DgxDLC74fIahvMZmmYsHGZGEOFrfsX/uA88=
 github.com/sirupsen/logrus v1.7.0 h1:ShrD1U9pZB12TX0cVy0DtePoCH97K8EtX+mg7ZARUtM=
 github.com/sirupsen/logrus v1.7.0/go.mod h1:yWOB1SBYBC5VeMP7gHvWumXLIWorT60ONWic61uBYv0=
+github.com/sleepinggenius2/gosmi v0.4.3 h1:99Zwzy1Cvgsh396sw07oR2G4ab88ILGZFMxSlGWnR6o=
+github.com/sleepinggenius2/gosmi v0.4.3/go.mod h1:l8OniPmd3bJzw0MXP2/qh7AhP/e+bTY2CNivIhsnDT0=
 github.com/smartystreets/assertions v0.0.0-20180927180507-b2de0cb4f26d h1:zE9ykElWQ6/NYmHa3jpm/yHnI4xSofP+UP6SpjHcSeM=
 github.com/smartystreets/assertions v0.0.0-20180927180507-b2de0cb4f26d/go.mod h1:OnSkiWE9lh6wB0YB77sQom3nweQdgAjqCqsofrRNTgc=
 github.com/smartystreets/goconvey v0.0.0-20190330032615-68dc04aab96a/go.mod h1:syvi0/a8iFYH4r/RixwvyeAJjdLS9QV7WQ/tjFTllLA=

plugins/inputs/snmp_trap/README.md

@@ -31,6 +31,10 @@ information.
   ## 1024.  See README.md for details
   ##
   # service_address = "udp://:162"
+  ##
+  ## Path to mib files
+  # path = ["/usr/share/snmp/mibs"]
+  ##
   ## Timeout running snmptranslate command
   # timeout = "5s"
   ## Snmp version

plugins/inputs/snmp_trap/snmp_trap.go

@@ -1,28 +1,25 @@
 package snmp_trap
 
 import (
-	"bufio"
-	"bytes"
 	"fmt"
 	"net"
-	"os/exec"
+	"os"
+	"path/filepath"
 	"strconv"
 	"strings"
-	"sync"
 	"time"
 
 	"github.com/influxdata/telegraf"
 	"github.com/influxdata/telegraf/config"
-	"github.com/influxdata/telegraf/internal"
 	"github.com/influxdata/telegraf/plugins/inputs"
+	"github.com/sleepinggenius2/gosmi"
+	"github.com/sleepinggenius2/gosmi/types"
 
 	"github.com/gosnmp/gosnmp"
 )
 
 var defaultTimeout = config.Duration(time.Second * 5)
 
-type execer func(config.Duration, string, ...string) ([]byte, error)
-
 type mibEntry struct {
 	mibName string
 	oidText string
@@ -32,6 +29,7 @@ type SnmpTrap struct {
 	ServiceAddress string          `toml:"service_address"`
 	Timeout        config.Duration `toml:"timeout"`
 	Version        string          `toml:"version"`
+	Path           []string        `toml:"path"`
 
 	// Settings for version 3
 	// Values: "noAuthNoPriv", "authNoPriv", "authPriv"
@@ -44,19 +42,15 @@ type SnmpTrap struct {
 	PrivProtocol string `toml:"priv_protocol"`
 	PrivPassword string `toml:"priv_password"`
 
-	acc      telegraf.Accumulator
+	acc        telegraf.Accumulator
-	listener *gosnmp.TrapListener
+	listener   *gosnmp.TrapListener
-	timeFunc func() time.Time
+	timeFunc   func() time.Time
-	errCh    chan error
+	lookupFunc func(string) (mibEntry, error)
+	errCh      chan error
 
 	makeHandlerWrapper func(gosnmp.TrapHandlerFunc) gosnmp.TrapHandlerFunc
 
 	Log telegraf.Logger `toml:"-"`
-
-	cacheLock sync.Mutex
-	cache     map[string]mibEntry
-
-	execCmd execer
 }
 
 var sampleConfig = `
@@ -68,6 +62,10 @@ var sampleConfig = `
   ## 1024.  See README.md for details
   ##
   # service_address = "udp://:162"
+  ##
+  ## Path to mib files
+  # path = ["/usr/share/snmp/mibs"]
+  ##
   ## Timeout running snmptranslate command
   # timeout = "5s"
   ## Snmp version, defaults to 2c
@@ -104,6 +102,7 @@ func init() {
 	inputs.Add("snmp_trap", func() telegraf.Input {
 		return &SnmpTrap{
 			timeFunc:       time.Now,
+			lookupFunc:     lookup,
 			ServiceAddress: "udp://:162",
 			Timeout:        defaultTimeout,
 			Version:        "2c",
@@ -111,20 +110,50 @@ func init() {
 	})
 }
 
-func realExecCmd(timeout config.Duration, arg0 string, args ...string) ([]byte, error) {
+func (s *SnmpTrap) Init() error {
-	cmd := exec.Command(arg0, args...)
+	// must init, append path for each directory, load module for every file
-	var out bytes.Buffer
+	// or gosmi will fail without saying why
-	cmd.Stdout = &out
+	gosmi.Init()
-	err := internal.RunTimeout(cmd, time.Duration(timeout))
+	err := s.getMibsPath()
 	if err != nil {
-		return nil, err
+		s.Log.Errorf("Could not get path %v", err)
 	}
-	return out.Bytes(), nil
+	return nil
 }
 
-func (s *SnmpTrap) Init() error {
+func (s *SnmpTrap) getMibsPath() error {
-	s.cache = map[string]mibEntry{}
+	var folders []string
-	s.execCmd = realExecCmd
+	for _, mibPath := range s.Path {
+		gosmi.AppendPath(mibPath)
+		folders = append(folders, mibPath)
+		err := filepath.Walk(mibPath, func(path string, info os.FileInfo, err error) error {
+			if info.Mode()&os.ModeSymlink != 0 {
+				s, _ := os.Readlink(path)
+				folders = append(folders, s)
+			}
+			return nil
+		})
+		if err != nil {
+			s.Log.Errorf("Filepath could not be walked %v", err)
+		}
+		for _, folder := range folders {
+			err := filepath.Walk(folder, func(path string, info os.FileInfo, err error) error {
+				if info.IsDir() {
+					gosmi.AppendPath(path)
+				} else if info.Mode()&os.ModeSymlink == 0 {
+					_, err := gosmi.LoadModule(info.Name())
+					if err != nil {
+						s.Log.Errorf("Module could not be loaded %v", err)
+					}
+				}
+				return nil
+			})
+			if err != nil {
+				s.Log.Errorf("Filepath could not be walked %v", err)
+			}
+		}
+		folders = []string{}
+	}
 	return nil
 }
 
@@ -248,6 +277,7 @@ func (s *SnmpTrap) Start(acc telegraf.Accumulator) error {
 
 func (s *SnmpTrap) Stop() {
 	s.listener.Close()
+	defer gosmi.Exit()
 	err := <-s.errCh
 	if nil != err {
 		s.Log.Errorf("Error stopping trap listener %v", err)
@@ -281,7 +311,7 @@ func makeTrapHandler(s *SnmpTrap) gosnmp.TrapHandlerFunc {
 			}
 
 			if trapOid != "" {
-				e, err := s.lookup(trapOid)
+				e, err := s.lookupFunc(trapOid)
 				if err != nil {
 					s.Log.Errorf("Error resolving V1 OID, oid=%s, source=%s: %v", trapOid, tags["source"], err)
 					return
@@ -319,7 +349,7 @@ func makeTrapHandler(s *SnmpTrap) gosnmp.TrapHandlerFunc {
 
 				var e mibEntry
 				var err error
-				e, err = s.lookup(val)
+				e, err = s.lookupFunc(val)
 				if nil != err {
 					s.Log.Errorf("Error resolving value OID, oid=%s, source=%s: %v", val, tags["source"], err)
 					return
@@ -337,7 +367,7 @@ func makeTrapHandler(s *SnmpTrap) gosnmp.TrapHandlerFunc {
 				value = v.Value
 			}
 
-			e, err := s.lookup(v.Name)
+			e, err := s.lookupFunc(v.Name)
 			if nil != err {
 				s.Log.Errorf("Error resolving OID oid=%s, source=%s: %v", v.Name, tags["source"], err)
 				return
@@ -366,48 +396,16 @@ func makeTrapHandler(s *SnmpTrap) gosnmp.TrapHandlerFunc {
 	}
 }
 
-func (s *SnmpTrap) lookup(oid string) (e mibEntry, err error) {
+func lookup(oid string) (e mibEntry, err error) {
-	s.cacheLock.Lock()
+	var node gosmi.SmiNode
-	defer s.cacheLock.Unlock()
+	node, err = gosmi.GetNodeByOID(types.OidMustFromString(oid))
-	var ok bool
-	if e, ok = s.cache[oid]; !ok {
-		// cache miss.  exec snmptranslate
-		e, err = s.snmptranslate(oid)
-		if err == nil {
-			s.cache[oid] = e
-		}
-		return e, err
-	}
-	return e, nil
-}
-
-func (s *SnmpTrap) clear() {
-	s.cacheLock.Lock()
-	defer s.cacheLock.Unlock()
-	s.cache = map[string]mibEntry{}
-}
-
-func (s *SnmpTrap) load(oid string, e mibEntry) {
-	s.cacheLock.Lock()
-	defer s.cacheLock.Unlock()
-	s.cache[oid] = e
-}
-
-func (s *SnmpTrap) snmptranslate(oid string) (e mibEntry, err error) {
-	var out []byte
-	out, err = s.execCmd(s.Timeout, "snmptranslate", "-Td", "-Ob", "-m", "all", oid)
 
+	// ensure modules are loaded or node will be empty (might not error)
 	if err != nil {
 		return e, err
 	}
 
-	scanner := bufio.NewScanner(bytes.NewBuffer(out))
+	e.oidText = node.RenderQualified()
-	ok := scanner.Scan()
-	if err = scanner.Err(); !ok && err != nil {
-		return e, err
-	}
-
-	e.oidText = scanner.Text()
 
 	i := strings.Index(e.oidText, "::")
 	if i == -1 {

plugins/inputs/snmp_trap/snmp_trap_test.go

@@ -3,6 +3,7 @@ package snmp_trap
 import (
 	"fmt"
 	"net"
+	"path/filepath"
 	"strconv"
 	"strings"
 	"testing"
@@ -11,35 +12,11 @@ import (
 	"github.com/gosnmp/gosnmp"
 
 	"github.com/influxdata/telegraf"
-	"github.com/influxdata/telegraf/config"
 	"github.com/influxdata/telegraf/testutil"
 
 	"github.com/stretchr/testify/require"
 )
 
-func TestLoad(t *testing.T) {
-	s := &SnmpTrap{}
-	require.Nil(t, s.Init())
-
-	defer s.clear()
-	s.load(
-		".1.3.6.1.6.3.1.1.5.1",
-		mibEntry{
-			"SNMPv2-MIB",
-			"coldStart",
-		},
-	)
-
-	e, err := s.lookup(".1.3.6.1.6.3.1.1.5.1")
-	require.NoError(t, err)
-	require.Equal(t, "SNMPv2-MIB", e.mibName)
-	require.Equal(t, "coldStart", e.oidText)
-}
-
-func fakeExecCmd(_ config.Duration, x string, y ...string) ([]byte, error) {
-	return nil, fmt.Errorf("mock " + x + " " + strings.Join(y, " "))
-}
-
 func newMsgFlagsV3(secLevel string) gosnmp.SnmpV3MsgFlags {
 	var msgFlags gosnmp.SnmpV3MsgFlags
 	switch strings.ToLower(secLevel) {
@@ -1284,6 +1261,15 @@ func TestReceiveTrap(t *testing.T) {
 				timeFunc: func() time.Time {
 					return fakeTime
 				},
+				lookupFunc: func(input string) (mibEntry, error) {
+					for _, entry := range tt.entries {
+						if input == entry.oid {
+							return mibEntry{entry.e.mibName, entry.e.oidText}, nil
+						}
+					}
+					return mibEntry{}, fmt.Errorf("Unexpected oid")
+				},
+				//if cold start be answer otherwise err
 				Log:          testutil.Logger{},
 				Version:      tt.version.String(),
 				SecName:      tt.secName,
@@ -1293,19 +1279,13 @@ func TestReceiveTrap(t *testing.T) {
 				PrivProtocol: tt.privProto,
 				PrivPassword: tt.privPass,
 			}
-			require.Nil(t, s.Init())
+
-			// Don't look up oid with snmptranslate.
+			require.NoError(t, s.Init())
-			s.execCmd = fakeExecCmd
+
 			var acc testutil.Accumulator
 			require.Nil(t, s.Start(&acc))
 			defer s.Stop()
 
-			// Preload the cache with the oids we'll use in this test
-			// so snmptranslate and mibs don't need to be installed.
-			for _, entry := range tt.entries {
-				s.load(entry.oid, entry.e)
-			}
-
 			var goSNMP gosnmp.GoSNMP
 			if tt.version == gosnmp.Version3 {
 				msgFlags := newMsgFlagsV3(tt.secLevel)
@@ -1331,4 +1311,98 @@ func TestReceiveTrap(t *testing.T) {
 				testutil.SortMetrics())
 		})
 	}
+
+}
+
+func TestGosmiSingleMib(t *testing.T) {
+	// We would prefer to specify port 0 and let the network
+	// stack choose an unused port for us but TrapListener
+	// doesn't have a way to return the autoselected port.
+	// Instead, we'll use an unusual port and hope it's
+	// unused.
+	const port = 12399
+
+	// Hook into the trap handler so the test knows when the
+	// trap has been received
+	received := make(chan int)
+	wrap := func(f gosnmp.TrapHandlerFunc) gosnmp.TrapHandlerFunc {
+		return func(p *gosnmp.SnmpPacket, a *net.UDPAddr) {
+			f(p, a)
+			received <- 0
+		}
+	}
+
+	fakeTime := time.Unix(456456456, 456)
+	now := uint32(123123123)
+
+	testDataPath, err := filepath.Abs("./testdata")
+	require.NoError(t, err)
+
+	trap := gosnmp.SnmpTrap{
+		Variables: []gosnmp.SnmpPDU{
+			{
+				Name:  ".1.3.6.1.2.1.1.3.0",
+				Type:  gosnmp.TimeTicks,
+				Value: now,
+			},
+			{
+				Name:  ".1.3.6.1.6.3.1.1.4.1.0", // SNMPv2-MIB::snmpTrapOID.0
+				Type:  gosnmp.ObjectIdentifier,
+				Value: ".1.3.6.1.6.3.1.1.5.1", // coldStart
+			},
+		},
+	}
+
+	metrics := []telegraf.Metric{
+		testutil.MustMetric(
+			"snmp_trap", // name
+			map[string]string{ // tags
+				"oid":       ".1.3.6.1.6.3.1.1.5.1",
+				"name":      "coldStart",
+				"mib":       "SNMPv2-MIB",
+				"version":   "2c",
+				"source":    "127.0.0.1",
+				"community": "public",
+			},
+			map[string]interface{}{ // fields
+				"sysUpTimeInstance": now,
+			},
+			fakeTime,
+		),
+	}
+
+	// Set up the service input plugin
+	s := &SnmpTrap{
+		ServiceAddress:     "udp://:" + strconv.Itoa(port),
+		makeHandlerWrapper: wrap,
+		timeFunc: func() time.Time {
+			return fakeTime
+		},
+		lookupFunc: lookup,
+		Log:        testutil.Logger{},
+		Version:    "2c",
+		Path:       []string{testDataPath},
+	}
+	require.NoError(t, s.Init())
+
+	var acc testutil.Accumulator
+	require.Nil(t, s.Start(&acc))
+	defer s.Stop()
+
+	goSNMP := newGoSNMP(gosnmp.Version2c, port)
+
+	// Send the trap
+	sendTrap(t, goSNMP, trap)
+
+	// Wait for trap to be received
+	select {
+	case <-received:
+	case <-time.After(2 * time.Second):
+		t.Fatal("timed out waiting for trap to be received")
+	}
+
+	// Verify plugin output
+	testutil.RequireMetricsEqual(t,
+		metrics, acc.GetTelegrafMetrics(),
+		testutil.SortMetrics())
 }

plugins/inputs/snmp_trap/testdata/test.mib

@@ -0,0 +1,40 @@
+SNMPv2-MIB DEFINITIONS ::= BEGIN
+
+IMPORTS 
+    NOTIFICATION-TYPE, NOTIFICATION-GROUP
+        FROM test2;
+
+
+snmpMIB MODULE-IDENTITY
+    LAST-UPDATED "2021060900Z"
+    ORGANIZATION "testing"
+    CONTACT-INFO
+        "EMail:  testing@emai.com"
+    DESCRIPTION
+        "MIB module for testing snmp_trap plugin
+        for telegraf
+        "
+    ::={ coldStart 1 }
+
+snmpMIBObjects OBJECT IDENTIFIER ::= { snmpMIB 1 } 
+
+system   OBJECT IDENTIFIER ::= { sysUpTimeInstance 1 }
+
+coldStart NOTIFICATION-TYPE
+    STATUS  current
+    DESCRIPTION
+            "A coldStart trap signifies that the SNMP entity,
+            supporting a notification originator application, is
+            reinitializing itself and that its configuration may
+            have been altered."
+    ::= { snmpTraps 1 }
+
+snmpBasicNotificationsGroup NOTIFICATION-GROUP
+    NOTIFICATIONS { coldStart, authenticationFailure }
+    STATUS        current
+    DESCRIPTION
+       "The basic notifications implemented by an SNMP entity
+        supporting command responder applications."
+    ::= { snmpMIBGroups 7 }
+
+END

plugins/inputs/snmp_trap/testdata/test2

@@ -0,0 +1,97 @@
+SNMPv2-MIB DEFINITIONS ::= BEGIN
+
+org            OBJECT IDENTIFIER ::= { iso 3 }  --  "iso" = 1
+dod            OBJECT IDENTIFIER ::= { org 6 }
+internet       OBJECT IDENTIFIER ::= { dod 1 }
+
+directory      OBJECT IDENTIFIER ::= { internet 1 }
+
+mgmt           OBJECT IDENTIFIER ::= { internet 2 }
+sysUpTimeInstance          OBJECT IDENTIFIER ::= { mgmt 1 }
+transmission   OBJECT IDENTIFIER ::= { sysUpTimeInstance 10 }
+
+experimental   OBJECT IDENTIFIER ::= { internet 3 }
+
+private        OBJECT IDENTIFIER ::= { internet 4 }
+enterprises    OBJECT IDENTIFIER ::= { private 1 }
+
+security       OBJECT IDENTIFIER ::= { internet 5 }
+
+snmpV2         OBJECT IDENTIFIER ::= { internet 6 }
+
+-- transport domains
+snmpDomains    OBJECT IDENTIFIER ::= { snmpV2 1 }
+
+-- transport proxies
+snmpProxys     OBJECT IDENTIFIER ::= { snmpV2 2 }
+
+-- module identities
+coldStart    OBJECT IDENTIFIER ::= { snmpV2 3 }
+
+NOTIFICATION-TYPE MACRO ::=
+BEGIN
+    TYPE NOTATION ::=
+                  ObjectsPart
+                  "STATUS" Status
+                  "DESCRIPTION" Text
+                  ReferPart
+
+    VALUE NOTATION ::=
+                  value(VALUE NotificationName)
+
+    ObjectsPart ::=
+                  "OBJECTS" "{" Objects "}"
+                | empty
+    Objects ::=
+                  Object
+
+                | Objects "," Object
+    Object ::=
+                  value(ObjectName)
+
+    Status ::=
+                  "current"
+                | "deprecated"
+                | "obsolete"
+
+    ReferPart ::=
+                  "REFERENCE" Text
+                | empty
+
+    -- a character string as defined in section 3.1.1
+    Text ::= value(IA5String)
+END
+
+NOTIFICATION-GROUP MACRO ::=
+BEGIN
+    TYPE NOTATION ::=
+                  NotificationsPart
+                  "STATUS" Status
+                  "DESCRIPTION" Text
+                  ReferPart
+
+    VALUE NOTATION ::=
+                  value(VALUE OBJECT IDENTIFIER)
+
+    NotificationsPart ::=
+                  "NOTIFICATIONS" "{" Notifications "}"
+    Notifications ::=
+                  Notification
+                | Notifications "," Notification
+    Notification ::=
+                  value(NotificationName)
+
+    Status ::=
+                  "current"
+                | "deprecated"
+                | "obsolete"
+
+    ReferPart ::=
+                  "REFERENCE" Text
+                | empty
+
+    -- a character string as defined in [2]
+    Text ::= value(IA5String)
+END
+
+END