Move to ldap.v3 to fix #5928 (#6105)

Signed-off-by: Andrew Thornton <art27@cantab.net>

vendor/gopkg.in/ldap.v3/passwdmodify.go

@@ -0,0 +1,157 @@
+// This file contains the password modify extended operation as specified in rfc 3062
+//
+// https://tools.ietf.org/html/rfc3062
+//
+
+package ldap
+
+import (
+	"errors"
+	"fmt"
+
+	"gopkg.in/asn1-ber.v1"
+)
+
+const (
+	passwordModifyOID = "1.3.6.1.4.1.4203.1.11.1"
+)
+
+// PasswordModifyRequest implements the Password Modify Extended Operation as defined in https://www.ietf.org/rfc/rfc3062.txt
+type PasswordModifyRequest struct {
+	// UserIdentity is an optional string representation of the user associated with the request.
+	// This string may or may not be an LDAPDN [RFC2253].
+	// If no UserIdentity field is present, the request acts up upon the password of the user currently associated with the LDAP session
+	UserIdentity string
+	// OldPassword, if present, contains the user's current password
+	OldPassword string
+	// NewPassword, if present, contains the desired password for this user
+	NewPassword string
+}
+
+// PasswordModifyResult holds the server response to a PasswordModifyRequest
+type PasswordModifyResult struct {
+	// GeneratedPassword holds a password generated by the server, if present
+	GeneratedPassword string
+	// Referral are the returned referral
+	Referral string
+}
+
+func (r *PasswordModifyRequest) encode() (*ber.Packet, error) {
+	request := ber.Encode(ber.ClassApplication, ber.TypeConstructed, ApplicationExtendedRequest, nil, "Password Modify Extended Operation")
+	request.AppendChild(ber.NewString(ber.ClassContext, ber.TypePrimitive, 0, passwordModifyOID, "Extended Request Name: Password Modify OID"))
+	extendedRequestValue := ber.Encode(ber.ClassContext, ber.TypePrimitive, 1, nil, "Extended Request Value: Password Modify Request")
+	passwordModifyRequestValue := ber.Encode(ber.ClassUniversal, ber.TypeConstructed, ber.TagSequence, nil, "Password Modify Request")
+	if r.UserIdentity != "" {
+		passwordModifyRequestValue.AppendChild(ber.NewString(ber.ClassContext, ber.TypePrimitive, 0, r.UserIdentity, "User Identity"))
+	}
+	if r.OldPassword != "" {
+		passwordModifyRequestValue.AppendChild(ber.NewString(ber.ClassContext, ber.TypePrimitive, 1, r.OldPassword, "Old Password"))
+	}
+	if r.NewPassword != "" {
+		passwordModifyRequestValue.AppendChild(ber.NewString(ber.ClassContext, ber.TypePrimitive, 2, r.NewPassword, "New Password"))
+	}
+
+	extendedRequestValue.AppendChild(passwordModifyRequestValue)
+	request.AppendChild(extendedRequestValue)
+
+	return request, nil
+}
+
+// NewPasswordModifyRequest creates a new PasswordModifyRequest
+//
+// According to the RFC 3602:
+// userIdentity is a string representing the user associated with the request.
+// This string may or may not be an LDAPDN (RFC 2253).
+// If userIdentity is empty then the operation will act on the user associated
+// with the session.
+//
+// oldPassword is the current user's password, it can be empty or it can be
+// needed depending on the session user access rights (usually an administrator
+// can change a user's password without knowing the current one) and the
+// password policy (see pwdSafeModify password policy's attribute)
+//
+// newPassword is the desired user's password. If empty the server can return
+// an error or generate a new password that will be available in the
+// PasswordModifyResult.GeneratedPassword
+//
+func NewPasswordModifyRequest(userIdentity string, oldPassword string, newPassword string) *PasswordModifyRequest {
+	return &PasswordModifyRequest{
+		UserIdentity: userIdentity,
+		OldPassword:  oldPassword,
+		NewPassword:  newPassword,
+	}
+}
+
+// PasswordModify performs the modification request
+func (l *Conn) PasswordModify(passwordModifyRequest *PasswordModifyRequest) (*PasswordModifyResult, 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"))
+
+	encodedPasswordModifyRequest, err := passwordModifyRequest.encode()
+	if err != nil {
+		return nil, err
+	}
+	packet.AppendChild(encodedPasswordModifyRequest)
+
+	l.Debug.PrintPacket(packet)
+
+	msgCtx, err := l.sendMessage(packet)
+	if err != nil {
+		return nil, err
+	}
+	defer l.finishMessage(msgCtx)
+
+	result := &PasswordModifyResult{}
+
+	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 {
+		err := GetLDAPError(packet)
+		if err != nil {
+			if IsErrorWithCode(err, LDAPResultReferral) {
+				for _, child := range packet.Children[1].Children {
+					if child.Tag == 3 {
+						result.Referral = child.Children[0].Value.(string)
+					}
+				}
+			}
+			return result, 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 {
+			passwordModifyResponseValue := ber.DecodePacket(child.Data.Bytes())
+			if len(passwordModifyResponseValue.Children) == 1 {
+				if passwordModifyResponseValue.Children[0].Tag == 0 {
+					result.GeneratedPassword = ber.DecodeString(passwordModifyResponseValue.Children[0].Data.Bytes())
+				}
+			}
+		}
+	}
+
+	return result, nil
+}