diff --git a/vendor/gopkg.in/jcmturner/gokrb5.v7/credentials/ccache.go b/vendor/gopkg.in/jcmturner/gokrb5.v7/credentials/ccache.go
new file mode 100644
index 0000000..98ec29b
--- /dev/null
+++ b/vendor/gopkg.in/jcmturner/gokrb5.v7/credentials/ccache.go
@@ -0,0 +1,348 @@
+package credentials
+
+import (
+	"bytes"
+	"encoding/binary"
+	"errors"
+	"io/ioutil"
+	"strings"
+	"time"
+	"unsafe"
+
+	"github.com/jcmturner/gofork/encoding/asn1"
+	"gopkg.in/jcmturner/gokrb5.v7/types"
+)
+
+const (
+	headerFieldTagKDCOffset = 1
+)
+
+// The first byte of the file always has the value 5.
+// The value of the second byte contains the version number (1 through 4)
+// Versions 1 and 2 of the file format use native byte order for integer representations.
+// Versions 3 and 4 always use big-endian byte order
+// After the two-byte version indicator, the file has three parts:
+//   1) the header (in version 4 only)
+//   2) the default principal name
+//   3) a sequence of credentials
+
+// CCache is the file credentials cache as define here: https://web.mit.edu/kerberos/krb5-latest/doc/formats/ccache_file_format.html
+type CCache struct {
+	Version          uint8
+	Header           header
+	DefaultPrincipal principal
+	Credentials      []*Credential
+	Path             string
+}
+
+type header struct {
+	length uint16
+	fields []headerField
+}
+
+type headerField struct {
+	tag    uint16
+	length uint16
+	value  []byte
+}
+
+// Credential cache entry principal struct.
+type principal struct {
+	Realm         string
+	PrincipalName types.PrincipalName
+}
+
+// Credential holds a Kerberos client's ccache credential information.
+type Credential struct {
+	Client       principal
+	Server       principal
+	Key          types.EncryptionKey
+	AuthTime     time.Time
+	StartTime    time.Time
+	EndTime      time.Time
+	RenewTill    time.Time
+	IsSKey       bool
+	TicketFlags  asn1.BitString
+	Addresses    []types.HostAddress
+	AuthData     []types.AuthorizationDataEntry
+	Ticket       []byte
+	SecondTicket []byte
+}
+
+// LoadCCache loads a credential cache file into a CCache type.
+func LoadCCache(cpath string) (*CCache, error) {
+	c := new(CCache)
+	b, err := ioutil.ReadFile(cpath)
+	if err != nil {
+		return c, err
+	}
+	err = c.Unmarshal(b)
+	return c, err
+}
+
+// Unmarshal a byte slice of credential cache data into CCache type.
+func (c *CCache) Unmarshal(b []byte) error {
+	p := 0
+	//The first byte of the file always has the value 5
+	if int8(b[p]) != 5 {
+		return errors.New("Invalid credential cache data. First byte does not equal 5")
+	}
+	p++
+	//Get credential cache version
+	//The second byte contains the version number (1 to 4)
+	c.Version = b[p]
+	if c.Version < 1 || c.Version > 4 {
+		return errors.New("Invalid credential cache data. Keytab version is not within 1 to 4")
+	}
+	p++
+	//Version 1 or 2 of the file format uses native byte order for integer representations. Versions 3 & 4 always uses big-endian byte order
+	var endian binary.ByteOrder
+	endian = binary.BigEndian
+	if (c.Version == 1 || c.Version == 2) && isNativeEndianLittle() {
+		endian = binary.LittleEndian
+	}
+	if c.Version == 4 {
+		err := parseHeader(b, &p, c, &endian)
+		if err != nil {
+			return err
+		}
+	}
+	c.DefaultPrincipal = parsePrincipal(b, &p, c, &endian)
+	for p < len(b) {
+		cred, err := parseCredential(b, &p, c, &endian)
+		if err != nil {
+			return err
+		}
+		c.Credentials = append(c.Credentials, cred)
+	}
+	return nil
+}
+
+func parseHeader(b []byte, p *int, c *CCache, e *binary.ByteOrder) error {
+	if c.Version != 4 {
+		return errors.New("Credentials cache version is not 4 so there is no header to parse.")
+	}
+	h := header{}
+	h.length = uint16(readInt16(b, p, e))
+	for *p <= int(h.length) {
+		f := headerField{}
+		f.tag = uint16(readInt16(b, p, e))
+		f.length = uint16(readInt16(b, p, e))
+		f.value = b[*p : *p+int(f.length)]
+		*p += int(f.length)
+		if !f.valid() {
+			return errors.New("Invalid credential cache header found")
+		}
+		h.fields = append(h.fields, f)
+	}
+	c.Header = h
+	return nil
+}
+
+// Parse the Keytab bytes of a principal into a Keytab entry's principal.
+func parsePrincipal(b []byte, p *int, c *CCache, e *binary.ByteOrder) (princ principal) {
+	if c.Version != 1 {
+		//Name Type is omitted in version 1
+		princ.PrincipalName.NameType = readInt32(b, p, e)
+	}
+	nc := int(readInt32(b, p, e))
+	if c.Version == 1 {
+		//In version 1 the number of components includes the realm. Minus 1 to make consistent with version 2
+		nc--
+	}
+	lenRealm := readInt32(b, p, e)
+	princ.Realm = string(readBytes(b, p, int(lenRealm), e))
+	for i := 0; i < nc; i++ {
+		l := readInt32(b, p, e)
+		princ.PrincipalName.NameString = append(princ.PrincipalName.NameString, string(readBytes(b, p, int(l), e)))
+	}
+	return princ
+}
+
+func parseCredential(b []byte, p *int, c *CCache, e *binary.ByteOrder) (cred *Credential, err error) {
+	cred = new(Credential)
+	cred.Client = parsePrincipal(b, p, c, e)
+	cred.Server = parsePrincipal(b, p, c, e)
+	key := types.EncryptionKey{}
+	key.KeyType = int32(readInt16(b, p, e))
+	if c.Version == 3 {
+		//repeated twice in version 3
+		key.KeyType = int32(readInt16(b, p, e))
+	}
+	key.KeyValue = readData(b, p, e)
+	cred.Key = key
+	cred.AuthTime = readTimestamp(b, p, e)
+	cred.StartTime = readTimestamp(b, p, e)
+	cred.EndTime = readTimestamp(b, p, e)
+	cred.RenewTill = readTimestamp(b, p, e)
+	if ik := readInt8(b, p, e); ik == 0 {
+		cred.IsSKey = false
+	} else {
+		cred.IsSKey = true
+	}
+	cred.TicketFlags = types.NewKrbFlags()
+	cred.TicketFlags.Bytes = readBytes(b, p, 4, e)
+	l := int(readInt32(b, p, e))
+	cred.Addresses = make([]types.HostAddress, l, l)
+	for i := range cred.Addresses {
+		cred.Addresses[i] = readAddress(b, p, e)
+	}
+	l = int(readInt32(b, p, e))
+	cred.AuthData = make([]types.AuthorizationDataEntry, l, l)
+	for i := range cred.AuthData {
+		cred.AuthData[i] = readAuthDataEntry(b, p, e)
+	}
+	cred.Ticket = readData(b, p, e)
+	cred.SecondTicket = readData(b, p, e)
+	return
+}
+
+// GetClientPrincipalName returns a PrincipalName type for the client the credentials cache is for.
+func (c *CCache) GetClientPrincipalName() types.PrincipalName {
+	return c.DefaultPrincipal.PrincipalName
+}
+
+// GetClientRealm returns the reals of the client the credentials cache is for.
+func (c *CCache) GetClientRealm() string {
+	return c.DefaultPrincipal.Realm
+}
+
+// GetClientCredentials returns a Credentials object representing the client of the credentials cache.
+func (c *CCache) GetClientCredentials() *Credentials {
+	return &Credentials{
+		username: c.DefaultPrincipal.PrincipalName.PrincipalNameString(),
+		realm:    c.GetClientRealm(),
+		cname:    c.DefaultPrincipal.PrincipalName,
+	}
+}
+
+// Contains tests if the cache contains a credential for the provided server PrincipalName
+func (c *CCache) Contains(p types.PrincipalName) bool {
+	for _, cred := range c.Credentials {
+		if cred.Server.PrincipalName.Equal(p) {
+			return true
+		}
+	}
+	return false
+}
+
+// GetEntry returns a specific credential for the PrincipalName provided.
+func (c *CCache) GetEntry(p types.PrincipalName) (*Credential, bool) {
+	cred := new(Credential)
+	var found bool
+	for i := range c.Credentials {
+		if c.Credentials[i].Server.PrincipalName.Equal(p) {
+			cred = c.Credentials[i]
+			found = true
+			break
+		}
+	}
+	if !found {
+		return cred, false
+	}
+	return cred, true
+}
+
+// GetEntries filters out configuration entries an returns a slice of credentials.
+func (c *CCache) GetEntries() []*Credential {
+	creds := make([]*Credential, 0)
+	for _, cred := range c.Credentials {
+		// Filter out configuration entries
+		if strings.HasPrefix(cred.Server.Realm, "X-CACHECONF") {
+			continue
+		}
+		creds = append(creds, cred)
+	}
+	return creds
+}
+
+func (h *headerField) valid() bool {
+	// At this time there is only one defined header field.
+	// Its tag value is 1, its length is always 8.
+	// Its contents are two 32-bit integers giving the seconds and microseconds
+	// of the time offset of the KDC relative to the client.
+	// Adding this offset to the current time on the client should give the current time on the KDC, if that offset has not changed since the initial authentication.
+
+	// Done as a switch in case other tag values are added in the future.
+	switch h.tag {
+	case headerFieldTagKDCOffset:
+		if h.length != 8 || len(h.value) != 8 {
+			return false
+		}
+		return true
+	}
+	return false
+}
+
+func readData(b []byte, p *int, e *binary.ByteOrder) []byte {
+	l := readInt32(b, p, e)
+	return readBytes(b, p, int(l), e)
+}
+
+func readAddress(b []byte, p *int, e *binary.ByteOrder) types.HostAddress {
+	a := types.HostAddress{}
+	a.AddrType = int32(readInt16(b, p, e))
+	a.Address = readData(b, p, e)
+	return a
+}
+
+func readAuthDataEntry(b []byte, p *int, e *binary.ByteOrder) types.AuthorizationDataEntry {
+	a := types.AuthorizationDataEntry{}
+	a.ADType = int32(readInt16(b, p, e))
+	a.ADData = readData(b, p, e)
+	return a
+}
+
+// Read bytes representing a timestamp.
+func readTimestamp(b []byte, p *int, e *binary.ByteOrder) time.Time {
+	return time.Unix(int64(readInt32(b, p, e)), 0)
+}
+
+// Read bytes representing an eight bit integer.
+func readInt8(b []byte, p *int, e *binary.ByteOrder) (i int8) {
+	buf := bytes.NewBuffer(b[*p : *p+1])
+	binary.Read(buf, *e, &i)
+	*p++
+	return
+}
+
+// Read bytes representing a sixteen bit integer.
+func readInt16(b []byte, p *int, e *binary.ByteOrder) (i int16) {
+	buf := bytes.NewBuffer(b[*p : *p+2])
+	binary.Read(buf, *e, &i)
+	*p += 2
+	return
+}
+
+// Read bytes representing a thirty two bit integer.
+func readInt32(b []byte, p *int, e *binary.ByteOrder) (i int32) {
+	buf := bytes.NewBuffer(b[*p : *p+4])
+	binary.Read(buf, *e, &i)
+	*p += 4
+	return
+}
+
+func readBytes(b []byte, p *int, s int, e *binary.ByteOrder) []byte {
+	buf := bytes.NewBuffer(b[*p : *p+s])
+	r := make([]byte, s)
+	binary.Read(buf, *e, &r)
+	*p += s
+	return r
+}
+
+func isNativeEndianLittle() bool {
+	var x = 0x012345678
+	var p = unsafe.Pointer(&x)
+	var bp = (*[4]byte)(p)
+
+	var endian bool
+	if 0x01 == bp[0] {
+		endian = false
+	} else if (0x78 & 0xff) == (bp[0] & 0xff) {
+		endian = true
+	} else {
+		// Default to big endian
+		endian = false
+	}
+	return endian
+}