Sync with Community

vendor/github.com/go-ldap/ldap/v3/whoami.go

@@ -0,0 +1,91 @@
+package ldap
+
+// This file contains the "Who Am I?" extended operation as specified in rfc 4532
+//
+// https://tools.ietf.org/html/rfc4532
+
+import (
+	"errors"
+	"fmt"
+
+	ber "github.com/go-asn1-ber/asn1-ber"
+)
+
+type whoAmIRequest bool
+
+// WhoAmIResult is returned by the WhoAmI() call
+type WhoAmIResult struct {
+	AuthzID string
+}
+
+func (r whoAmIRequest) encode() (*ber.Packet, error) {
+	request := ber.Encode(ber.ClassApplication, ber.TypeConstructed, ApplicationExtendedRequest, nil, "Who Am I? Extended Operation")
+	request.AppendChild(ber.NewString(ber.ClassContext, ber.TypePrimitive, 0, ControlTypeWhoAmI, "Extended Request Name: Who Am I? OID"))
+	return request, nil
+}
+
+// WhoAmI returns the authzId the server thinks we are, you may pass controls
+// like a Proxied Authorization control
+func (l *Conn) WhoAmI(controls []Control) (*WhoAmIResult, error) {
+	packet := ber.Encode(ber.ClassUniversal, ber.TypeConstructed, ber.TagSequence, nil, "LDAP Request")
+	packet.AppendChild(ber.NewInteger(ber.ClassUniversal, ber.TypePrimitive, ber.TagInteger, l.nextMessageID(), "MessageID"))
+	req := whoAmIRequest(true)
+	encodedWhoAmIRequest, err := req.encode()
+	if err != nil {
+		return nil, err
+	}
+	packet.AppendChild(encodedWhoAmIRequest)
+
+	if len(controls) != 0 {
+		packet.AppendChild(encodeControls(controls))
+	}
+
+	l.Debug.PrintPacket(packet)
+
+	msgCtx, err := l.sendMessage(packet)
+	if err != nil {
+		return nil, err
+	}
+	defer l.finishMessage(msgCtx)
+
+	result := &WhoAmIResult{}
+
+	l.Debug.Printf("%d: waiting for response", msgCtx.id)
+	packetResponse, ok := <-msgCtx.responses
+	if !ok {
+		return nil, NewError(ErrorNetwork, errors.New("ldap: response channel closed"))
+	}
+	packet, err = packetResponse.ReadPacket()
+	l.Debug.Printf("%d: got response %p", msgCtx.id, packet)
+	if err != nil {
+		return nil, err
+	}
+
+	if packet == nil {
+		return nil, NewError(ErrorNetwork, errors.New("ldap: could not retrieve message"))
+	}
+
+	if l.Debug {
+		if err := addLDAPDescriptions(packet); err != nil {
+			return nil, err
+		}
+		ber.PrintPacket(packet)
+	}
+
+	if packet.Children[1].Tag == ApplicationExtendedResponse {
+		if err := GetLDAPError(packet); err != nil {
+			return nil, err
+		}
+	} else {
+		return nil, NewError(ErrorUnexpectedResponse, fmt.Errorf("Unexpected Response: %d", packet.Children[1].Tag))
+	}
+
+	extendedResponse := packet.Children[1]
+	for _, child := range extendedResponse.Children {
+		if child.Tag == 11 {
+			result.AuthzID = ber.DecodeString(child.Data.Bytes())
+		}
+	}
+
+	return result, nil
+}