diff --git a/vendor/github.com/jcmturner/gokrb5/v8/client/cache.go b/vendor/github.com/jcmturner/gokrb5/v8/client/cache.go
new file mode 100644
index 0000000..552e73e
--- /dev/null
+++ b/vendor/github.com/jcmturner/gokrb5/v8/client/cache.go
@@ -0,0 +1,134 @@
+package client
+
+import (
+	"encoding/json"
+	"errors"
+	"sort"
+	"sync"
+	"time"
+
+	"github.com/jcmturner/gokrb5/v8/messages"
+	"github.com/jcmturner/gokrb5/v8/types"
+)
+
+// Cache for service tickets held by the client.
+type Cache struct {
+	Entries map[string]CacheEntry
+	mux     sync.RWMutex
+}
+
+// CacheEntry holds details for a cache entry.
+type CacheEntry struct {
+	SPN        string
+	Ticket     messages.Ticket `json:"-"`
+	AuthTime   time.Time
+	StartTime  time.Time
+	EndTime    time.Time
+	RenewTill  time.Time
+	SessionKey types.EncryptionKey `json:"-"`
+}
+
+// NewCache creates a new client ticket cache instance.
+func NewCache() *Cache {
+	return &Cache{
+		Entries: map[string]CacheEntry{},
+	}
+}
+
+// getEntry returns a cache entry that matches the SPN.
+func (c *Cache) getEntry(spn string) (CacheEntry, bool) {
+	c.mux.RLock()
+	defer c.mux.RUnlock()
+	e, ok := (*c).Entries[spn]
+	return e, ok
+}
+
+// JSON returns information about the cached service tickets in a JSON format.
+func (c *Cache) JSON() (string, error) {
+	c.mux.RLock()
+	defer c.mux.RUnlock()
+	var es []CacheEntry
+	keys := make([]string, 0, len(c.Entries))
+	for k := range c.Entries {
+		keys = append(keys, k)
+	}
+	sort.Strings(keys)
+	for _, k := range keys {
+		es = append(es, c.Entries[k])
+	}
+	b, err := json.MarshalIndent(&es, "", "  ")
+	if err != nil {
+		return "", err
+	}
+	return string(b), nil
+}
+
+// addEntry adds a ticket to the cache.
+func (c *Cache) addEntry(tkt messages.Ticket, authTime, startTime, endTime, renewTill time.Time, sessionKey types.EncryptionKey) CacheEntry {
+	spn := tkt.SName.PrincipalNameString()
+	c.mux.Lock()
+	defer c.mux.Unlock()
+	(*c).Entries[spn] = CacheEntry{
+		SPN:        spn,
+		Ticket:     tkt,
+		AuthTime:   authTime,
+		StartTime:  startTime,
+		EndTime:    endTime,
+		RenewTill:  renewTill,
+		SessionKey: sessionKey,
+	}
+	return c.Entries[spn]
+}
+
+// clear deletes all the cache entries
+func (c *Cache) clear() {
+	c.mux.Lock()
+	defer c.mux.Unlock()
+	for k := range c.Entries {
+		delete(c.Entries, k)
+	}
+}
+
+// RemoveEntry removes the cache entry for the defined SPN.
+func (c *Cache) RemoveEntry(spn string) {
+	c.mux.Lock()
+	defer c.mux.Unlock()
+	delete(c.Entries, spn)
+}
+
+// GetCachedTicket returns a ticket from the cache for the SPN.
+// Only a ticket that is currently valid will be returned.
+func (cl *Client) GetCachedTicket(spn string) (messages.Ticket, types.EncryptionKey, bool) {
+	if e, ok := cl.cache.getEntry(spn); ok {
+		//If within time window of ticket return it
+		if time.Now().UTC().After(e.StartTime) && time.Now().UTC().Before(e.EndTime) {
+			cl.Log("ticket received from cache for %s", spn)
+			return e.Ticket, e.SessionKey, true
+		} else if time.Now().UTC().Before(e.RenewTill) {
+			e, err := cl.renewTicket(e)
+			if err != nil {
+				return e.Ticket, e.SessionKey, false
+			}
+			return e.Ticket, e.SessionKey, true
+		}
+	}
+	var tkt messages.Ticket
+	var key types.EncryptionKey
+	return tkt, key, false
+}
+
+// renewTicket renews a cache entry ticket.
+// To renew from outside the client package use GetCachedTicket
+func (cl *Client) renewTicket(e CacheEntry) (CacheEntry, error) {
+	spn := e.Ticket.SName
+	_, _, err := cl.TGSREQGenerateAndExchange(spn, e.Ticket.Realm, e.Ticket, e.SessionKey, true)
+	if err != nil {
+		return e, err
+	}
+	e, ok := cl.cache.getEntry(e.Ticket.SName.PrincipalNameString())
+	if !ok {
+		return e, errors.New("ticket was not added to cache")
+	}
+	cl.Log("ticket renewed for %s (EndTime: %v)", spn.PrincipalNameString(), e.EndTime)
+	return e, nil
+}