feat: add extended requests

client.go

@@ -28,6 +28,7 @@ type Client interface {
 	Modify(*ModifyRequest) error
 	ModifyDN(*ModifyDNRequest) error
 	ModifyWithResult(*ModifyRequest) (*ModifyResult, error)
+	Extended(*ExtendedRequest) (*ExtendResponse, error)
 
 	Compare(dn, attribute, value string) (bool, error)
 	PasswordModify(*PasswordModifyRequest) (*PasswordModifyResult, error)

extend.go

@@ -0,0 +1,73 @@
+package ldap
+
+import (
+	"fmt"
+	ber "github.com/go-asn1-ber/asn1-ber"
+)
+
+// ExtendedRequest TODO
+// See: https://www.rfc-editor.org/rfc/rfc4511#section-4.12
+type ExtendedRequest struct {
+	Name  string
+	Value string
+}
+
+func NewExtendedRequest(name, value string) *ExtendedRequest {
+	return &ExtendedRequest{
+		Name:  name,
+		Value: value,
+	}
+}
+
+func (er ExtendedRequest) appendTo(envelope *ber.Packet) error {
+	// ExtendedRequest ::= [APPLICATION 23] SEQUENCE {
+	// 	requestName      [0] LDAPOID,
+	// 	requestValue     [1] OCTET STRING OPTIONAL }
+	//
+	// Despite the RFC documentation stating otherwise, the requestName field needs to be
+	// of class application and type EOC, otherwise the directory server will terminate
+	// the connection right away (tested against OpenLDAP, Active Directory).
+	pkt := ber.Encode(ber.ClassApplication, ber.TypeConstructed, ApplicationExtendedRequest, nil, "Extend Request")
+	pkt.AppendChild(ber.NewString(ber.ClassContext, ber.TypePrimitive, ber.TagEOC, er.Name, "Extension Name"))
+	if er.Value != "" {
+		pkt.AppendChild(ber.NewString(ber.ClassUniversal, ber.TypePrimitive, ber.TagOctetString, er.Value, "Extension Value"))
+	}
+	envelope.AppendChild(pkt)
+	return nil
+}
+
+type ExtendResponse struct {
+	Name  string
+	Value string
+}
+
+func (l *Conn) Extended(er *ExtendedRequest) (*ExtendResponse, error) {
+	msgCtx, err := l.doRequest(er)
+	if err != nil {
+		return nil, err
+	}
+	defer l.finishMessage(msgCtx)
+
+	// ExtendedResponse ::= [APPLICATION 24] SEQUENCE {
+	//   COMPONENTS OF LDAPResult,
+	//   responseName     [10] LDAPOID OPTIONAL,
+	//   responseValue    [11] OCTET STRING OPTIONAL }
+	packet, err := l.readPacket(msgCtx)
+	if err != nil {
+		return nil, err
+	}
+	if len(packet.Children) < 2 || len(packet.Children[1].Children) < 4 {
+		return nil, fmt.Errorf(
+			"ldap: malformed extended response: expected 4 children, got: %d",
+			len(packet.Children),
+		)
+	}
+
+	response := new(ExtendResponse)
+	response.Name = packet.Children[1].Children[3].Data.String()
+	if len(packet.Children) == 4 {
+		response.Value = packet.Children[1].Children[4].Data.String()
+	}
+
+	return response, nil
+}

v3/client.go

@@ -28,6 +28,7 @@ type Client interface {
 	Modify(*ModifyRequest) error
 	ModifyDN(*ModifyDNRequest) error
 	ModifyWithResult(*ModifyRequest) (*ModifyResult, error)
+	Extended(*ExtendedRequest) (*ExtendResponse, error)
 
 	Compare(dn, attribute, value string) (bool, error)
 	PasswordModify(*PasswordModifyRequest) (*PasswordModifyResult, error)

v3/extend.go

@@ -0,0 +1,73 @@
+package ldap
+
+import (
+	"fmt"
+	ber "github.com/go-asn1-ber/asn1-ber"
+)
+
+// ExtendedRequest TODO
+// See: https://www.rfc-editor.org/rfc/rfc4511#section-4.12
+type ExtendedRequest struct {
+	Name  string
+	Value string
+}
+
+func NewExtendedRequest(name, value string) *ExtendedRequest {
+	return &ExtendedRequest{
+		Name:  name,
+		Value: value,
+	}
+}
+
+func (er ExtendedRequest) appendTo(envelope *ber.Packet) error {
+	// ExtendedRequest ::= [APPLICATION 23] SEQUENCE {
+	// 	requestName      [0] LDAPOID,
+	// 	requestValue     [1] OCTET STRING OPTIONAL }
+	//
+	// Despite the RFC documentation stating otherwise, the requestName field needs to be
+	// of class application and type EOC, otherwise the directory server will terminate
+	// the connection right away (tested against OpenLDAP, Active Directory).
+	pkt := ber.Encode(ber.ClassApplication, ber.TypeConstructed, ApplicationExtendedRequest, nil, "Extend Request")
+	pkt.AppendChild(ber.NewString(ber.ClassContext, ber.TypePrimitive, ber.TagEOC, er.Name, "Extension Name"))
+	if er.Value != "" {
+		pkt.AppendChild(ber.NewString(ber.ClassUniversal, ber.TypePrimitive, ber.TagOctetString, er.Value, "Extension Value"))
+	}
+	envelope.AppendChild(pkt)
+	return nil
+}
+
+type ExtendResponse struct {
+	Name  string
+	Value string
+}
+
+func (l *Conn) Extended(er *ExtendedRequest) (*ExtendResponse, error) {
+	msgCtx, err := l.doRequest(er)
+	if err != nil {
+		return nil, err
+	}
+	defer l.finishMessage(msgCtx)
+
+	// ExtendedResponse ::= [APPLICATION 24] SEQUENCE {
+	//   COMPONENTS OF LDAPResult,
+	//   responseName     [10] LDAPOID OPTIONAL,
+	//   responseValue    [11] OCTET STRING OPTIONAL }
+	packet, err := l.readPacket(msgCtx)
+	if err != nil {
+		return nil, err
+	}
+	if len(packet.Children) < 2 || len(packet.Children[1].Children) < 4 {
+		return nil, fmt.Errorf(
+			"ldap: malformed extended response: expected 4 children, got: %d",
+			len(packet.Children),
+		)
+	}
+
+	response := new(ExtendResponse)
+	response.Name = packet.Children[1].Children[3].Data.String()
+	if len(packet.Children) == 4 {
+		response.Value = packet.Children[1].Children[4].Data.String()
+	}
+
+	return response, nil
+}