[VOL-4291] Rw-core updates for gRPC migration
Change-Id: I8d5a554409115b29318089671ca4e1ab3fa98810
diff --git a/vendor/github.com/jcmturner/gokrb5/v8/client/network.go b/vendor/github.com/jcmturner/gokrb5/v8/client/network.go
new file mode 100644
index 0000000..634f015
--- /dev/null
+++ b/vendor/github.com/jcmturner/gokrb5/v8/client/network.go
@@ -0,0 +1,218 @@
+package client
+
+import (
+ "encoding/binary"
+ "errors"
+ "fmt"
+ "io"
+ "net"
+ "strings"
+ "time"
+
+ "github.com/jcmturner/gokrb5/v8/iana/errorcode"
+ "github.com/jcmturner/gokrb5/v8/messages"
+)
+
+// SendToKDC performs network actions to send data to the KDC.
+func (cl *Client) sendToKDC(b []byte, realm string) ([]byte, error) {
+ var rb []byte
+ if cl.Config.LibDefaults.UDPPreferenceLimit == 1 {
+ //1 means we should always use TCP
+ rb, errtcp := cl.sendKDCTCP(realm, b)
+ if errtcp != nil {
+ if e, ok := errtcp.(messages.KRBError); ok {
+ return rb, e
+ }
+ return rb, fmt.Errorf("communication error with KDC via TCP: %v", errtcp)
+ }
+ return rb, nil
+ }
+ if len(b) <= cl.Config.LibDefaults.UDPPreferenceLimit {
+ //Try UDP first, TCP second
+ rb, errudp := cl.sendKDCUDP(realm, b)
+ if errudp != nil {
+ if e, ok := errudp.(messages.KRBError); ok && e.ErrorCode != errorcode.KRB_ERR_RESPONSE_TOO_BIG {
+ // Got a KRBError from KDC
+ // If this is not a KRB_ERR_RESPONSE_TOO_BIG we will return immediately otherwise will try TCP.
+ return rb, e
+ }
+ // Try TCP
+ r, errtcp := cl.sendKDCTCP(realm, b)
+ if errtcp != nil {
+ if e, ok := errtcp.(messages.KRBError); ok {
+ // Got a KRBError
+ return r, e
+ }
+ return r, fmt.Errorf("failed to communicate with KDC. Attempts made with UDP (%v) and then TCP (%v)", errudp, errtcp)
+ }
+ rb = r
+ }
+ return rb, nil
+ }
+ //Try TCP first, UDP second
+ rb, errtcp := cl.sendKDCTCP(realm, b)
+ if errtcp != nil {
+ if e, ok := errtcp.(messages.KRBError); ok {
+ // Got a KRBError from KDC so returning and not trying UDP.
+ return rb, e
+ }
+ rb, errudp := cl.sendKDCUDP(realm, b)
+ if errudp != nil {
+ if e, ok := errudp.(messages.KRBError); ok {
+ // Got a KRBError
+ return rb, e
+ }
+ return rb, fmt.Errorf("failed to communicate with KDC. Attempts made with TCP (%v) and then UDP (%v)", errtcp, errudp)
+ }
+ }
+ return rb, nil
+}
+
+// sendKDCUDP sends bytes to the KDC via UDP.
+func (cl *Client) sendKDCUDP(realm string, b []byte) ([]byte, error) {
+ var r []byte
+ _, kdcs, err := cl.Config.GetKDCs(realm, false)
+ if err != nil {
+ return r, err
+ }
+ r, err = dialSendUDP(kdcs, b)
+ if err != nil {
+ return r, err
+ }
+ return checkForKRBError(r)
+}
+
+// dialSendUDP establishes a UDP connection to a KDC.
+func dialSendUDP(kdcs map[int]string, b []byte) ([]byte, error) {
+ var errs []string
+ for i := 1; i <= len(kdcs); i++ {
+ udpAddr, err := net.ResolveUDPAddr("udp", kdcs[i])
+ if err != nil {
+ errs = append(errs, fmt.Sprintf("error resolving KDC address: %v", err))
+ continue
+ }
+
+ conn, err := net.DialTimeout("udp", udpAddr.String(), 5*time.Second)
+ if err != nil {
+ errs = append(errs, fmt.Sprintf("error setting dial timeout on connection to %s: %v", kdcs[i], err))
+ continue
+ }
+ if err := conn.SetDeadline(time.Now().Add(5 * time.Second)); err != nil {
+ errs = append(errs, fmt.Sprintf("error setting deadline on connection to %s: %v", kdcs[i], err))
+ continue
+ }
+ // conn is guaranteed to be a UDPConn
+ rb, err := sendUDP(conn.(*net.UDPConn), b)
+ if err != nil {
+ errs = append(errs, fmt.Sprintf("error sneding to %s: %v", kdcs[i], err))
+ continue
+ }
+ return rb, nil
+ }
+ return nil, fmt.Errorf("error sending to a KDC: %s", strings.Join(errs, "; "))
+}
+
+// sendUDP sends bytes to connection over UDP.
+func sendUDP(conn *net.UDPConn, b []byte) ([]byte, error) {
+ var r []byte
+ defer conn.Close()
+ _, err := conn.Write(b)
+ if err != nil {
+ return r, fmt.Errorf("error sending to (%s): %v", conn.RemoteAddr().String(), err)
+ }
+ udpbuf := make([]byte, 4096)
+ n, _, err := conn.ReadFrom(udpbuf)
+ r = udpbuf[:n]
+ if err != nil {
+ return r, fmt.Errorf("sending over UDP failed to %s: %v", conn.RemoteAddr().String(), err)
+ }
+ if len(r) < 1 {
+ return r, fmt.Errorf("no response data from %s", conn.RemoteAddr().String())
+ }
+ return r, nil
+}
+
+// sendKDCTCP sends bytes to the KDC via TCP.
+func (cl *Client) sendKDCTCP(realm string, b []byte) ([]byte, error) {
+ var r []byte
+ _, kdcs, err := cl.Config.GetKDCs(realm, true)
+ if err != nil {
+ return r, err
+ }
+ r, err = dialSendTCP(kdcs, b)
+ if err != nil {
+ return r, err
+ }
+ return checkForKRBError(r)
+}
+
+// dialKDCTCP establishes a TCP connection to a KDC.
+func dialSendTCP(kdcs map[int]string, b []byte) ([]byte, error) {
+ var errs []string
+ for i := 1; i <= len(kdcs); i++ {
+ tcpAddr, err := net.ResolveTCPAddr("tcp", kdcs[i])
+ if err != nil {
+ errs = append(errs, fmt.Sprintf("error resolving KDC address: %v", err))
+ continue
+ }
+
+ conn, err := net.DialTimeout("tcp", tcpAddr.String(), 5*time.Second)
+ if err != nil {
+ errs = append(errs, fmt.Sprintf("error setting dial timeout on connection to %s: %v", kdcs[i], err))
+ continue
+ }
+ if err := conn.SetDeadline(time.Now().Add(5 * time.Second)); err != nil {
+ errs = append(errs, fmt.Sprintf("error setting deadline on connection to %s: %v", kdcs[i], err))
+ continue
+ }
+ // conn is guaranteed to be a TCPConn
+ rb, err := sendTCP(conn.(*net.TCPConn), b)
+ if err != nil {
+ errs = append(errs, fmt.Sprintf("error sneding to %s: %v", kdcs[i], err))
+ continue
+ }
+ return rb, nil
+ }
+ return nil, errors.New("error in getting a TCP connection to any of the KDCs")
+}
+
+// sendTCP sends bytes to connection over TCP.
+func sendTCP(conn *net.TCPConn, b []byte) ([]byte, error) {
+ defer conn.Close()
+ var r []byte
+ // RFC 4120 7.2.2 specifies the first 4 bytes indicate the length of the message in big endian order.
+ hb := make([]byte, 4, 4)
+ binary.BigEndian.PutUint32(hb, uint32(len(b)))
+ b = append(hb, b...)
+
+ _, err := conn.Write(b)
+ if err != nil {
+ return r, fmt.Errorf("error sending to KDC (%s): %v", conn.RemoteAddr().String(), err)
+ }
+
+ sh := make([]byte, 4, 4)
+ _, err = conn.Read(sh)
+ if err != nil {
+ return r, fmt.Errorf("error reading response size header: %v", err)
+ }
+ s := binary.BigEndian.Uint32(sh)
+
+ rb := make([]byte, s, s)
+ _, err = io.ReadFull(conn, rb)
+ if err != nil {
+ return r, fmt.Errorf("error reading response: %v", err)
+ }
+ if len(rb) < 1 {
+ return r, fmt.Errorf("no response data from KDC %s", conn.RemoteAddr().String())
+ }
+ return rb, nil
+}
+
+// checkForKRBError checks if the response bytes from the KDC are a KRBError.
+func checkForKRBError(b []byte) ([]byte, error) {
+ var KRBErr messages.KRBError
+ if err := KRBErr.Unmarshal(b); err == nil {
+ return b, KRBErr
+ }
+ return b, nil
+}