VOL-2496 Add "event listen" command to voltctl

Change-Id: I8f1fb34b55f56c8125142ac289e2f19fc170d804
diff --git a/vendor/gopkg.in/jcmturner/gokrb5.v7/types/Authenticator.go b/vendor/gopkg.in/jcmturner/gokrb5.v7/types/Authenticator.go
new file mode 100644
index 0000000..500e034
--- /dev/null
+++ b/vendor/gopkg.in/jcmturner/gokrb5.v7/types/Authenticator.go
@@ -0,0 +1,100 @@
+// Package types provides Kerberos 5 data types.
+package types
+
+import (
+	"crypto/rand"
+	"fmt"
+	"math"
+	"math/big"
+	"time"
+
+	"github.com/jcmturner/gofork/encoding/asn1"
+	"gopkg.in/jcmturner/gokrb5.v7/asn1tools"
+	"gopkg.in/jcmturner/gokrb5.v7/iana"
+	"gopkg.in/jcmturner/gokrb5.v7/iana/asnAppTag"
+)
+
+/*Authenticator   ::= [APPLICATION 2] SEQUENCE  {
+authenticator-vno       [0] INTEGER (5),
+crealm                  [1] Realm,
+cname                   [2] PrincipalName,
+cksum                   [3] Checksum OPTIONAL,
+cusec                   [4] Microseconds,
+ctime                   [5] KerberosTime,
+subkey                  [6] EncryptionKey OPTIONAL,
+seq-number              [7] UInt32 OPTIONAL,
+authorization-data      [8] AuthorizationData OPTIONAL
+}
+
+   cksum
+      This field contains a checksum of the application data that
+      accompanies the KRB_AP_REQ, computed using a key usage value of 10
+      in normal application exchanges, or 6 when used in the TGS-REQ
+      PA-TGS-REQ AP-DATA field.
+
+*/
+
+// Authenticator - A record containing information that can be shown to have been recently generated using the session key known only by the client and server.
+// https://tools.ietf.org/html/rfc4120#section-5.5.1
+type Authenticator struct {
+	AVNO              int               `asn1:"explicit,tag:0"`
+	CRealm            string            `asn1:"generalstring,explicit,tag:1"`
+	CName             PrincipalName     `asn1:"explicit,tag:2"`
+	Cksum             Checksum          `asn1:"explicit,optional,tag:3"`
+	Cusec             int               `asn1:"explicit,tag:4"`
+	CTime             time.Time         `asn1:"generalized,explicit,tag:5"`
+	SubKey            EncryptionKey     `asn1:"explicit,optional,tag:6"`
+	SeqNumber         int64             `asn1:"explicit,optional,tag:7"`
+	AuthorizationData AuthorizationData `asn1:"explicit,optional,tag:8"`
+}
+
+// NewAuthenticator creates a new Authenticator.
+func NewAuthenticator(realm string, cname PrincipalName) (Authenticator, error) {
+	seq, err := rand.Int(rand.Reader, big.NewInt(math.MaxUint32))
+	if err != nil {
+		return Authenticator{}, err
+	}
+	t := time.Now().UTC()
+	return Authenticator{
+		AVNO:      iana.PVNO,
+		CRealm:    realm,
+		CName:     cname,
+		Cksum:     Checksum{},
+		Cusec:     int((t.UnixNano() / int64(time.Microsecond)) - (t.Unix() * 1e6)),
+		CTime:     t,
+		SeqNumber: seq.Int64(),
+	}, nil
+}
+
+// GenerateSeqNumberAndSubKey sets the Authenticator's sequence number and subkey.
+func (a *Authenticator) GenerateSeqNumberAndSubKey(keyType int32, keySize int) error {
+	seq, err := rand.Int(rand.Reader, big.NewInt(math.MaxUint32))
+	if err != nil {
+		return err
+	}
+	a.SeqNumber = seq.Int64()
+	//Generate subkey value
+	sk := make([]byte, keySize, keySize)
+	rand.Read(sk)
+	a.SubKey = EncryptionKey{
+		KeyType:  keyType,
+		KeyValue: sk,
+	}
+	return nil
+}
+
+// Unmarshal bytes into the Authenticator.
+func (a *Authenticator) Unmarshal(b []byte) error {
+	_, err := asn1.UnmarshalWithParams(b, a, fmt.Sprintf("application,explicit,tag:%v", asnAppTag.Authenticator))
+	return err
+}
+
+// Marshal the Authenticator.
+func (a *Authenticator) Marshal() ([]byte, error) {
+	b, err := asn1.Marshal(*a)
+	if err != nil {
+		return nil, err
+	}
+	b = asn1tools.AddASNAppTag(b, asnAppTag.Authenticator)
+	return b, nil
+}