Support LDAP_SERVER_EXTENDED_DN_OID microsoft extension

[styleex]

It's protocol extension is very useful for query the user with his list of security groups GUID, in a single request

More info: https://msdn.microsoft.com/en-us/library/aa366980(v=vs.85).aspx
http://ldap3.readthedocs.io/ldap3.protocol.microsoft.html#ldap3.protocol.microsoft.ExtendedDN
noirello/bonsai#6

[styleex]

Do you have any thoughts about the task? Or a workaround?

[project0]

Hmm, try this one:

// ldapControlServerPolicyHints mplements ldap.Control
type ldapControlServerExtendDN struct {
   Critical bool
   Flag int
}

// GetControlType implements ldap.Control
func (c *ldapControlServerExtendDN) GetControlType() string {
	return "1.2.840.113556.1.4.529"
}

// Encode implements ldap.Control
func (c *ldapControlServerExtendDN) Encode() *ber.Packet {
	packet := ber.Encode(ber.ClassUniversal, ber.TypeConstructed, ber.TagSequence, nil, "Control")
	packet.AppendChild(ber.NewString(ber.ClassUniversal, ber.TypePrimitive, ber.TagOctetString, c.GetControlType(), "Control Type (LDAP_SERVER_EXTENDED_DN_OID)"))
	packet.AppendChild(ber.NewBoolean(ber.ClassUniversal, ber.TypePrimitive, ber.TagBoolean, c.Critical, "Criticality"))

	p2 := ber.Encode(ber.ClassUniversal, ber.TypePrimitive, ber.TagOctetString, nil, "Control Value (Extend DN)")
	seq := ber.Encode(ber.ClassUniversal, ber.TypeConstructed, ber.TagSequence, nil, "ExtendDNRequestValue")
	seq.AppendChild(ber.NewInteger(ber.ClassUniversal, ber.TypePrimitive, ber.TagInteger, c.Flag, "Flags"))
	p2.AppendChild(seq)
	packet.AppendChild(p2)

	return packet
}

// String implements ldap.Control
func (c *ldapControlServerExtendDN) String() string {
	return "Extend DN request with objectGUID and objectSID: " + c.GetControlType()
}

[johnweldon]

Feel free to propose a PR @project0

[dhawal55]

@project0 I tried your control but couldn't get objectSid. Also, I don't want to extend DN, just want to get objectSid in string format. Any ideas?

[project0]

@dhawal55 just tried it out and it works as expected. It returns the extended DN: DN: <GUID=b546bb170f5b33448fd4ca834b8c4735>;<SID=0105000000000005150000007a22231029e948f6738af5a3881d0000>;CN=xxxx
did you forget to add the new Control?
searchRequest.Controls = append(searchRequest.Controls, &ldapControlServerExtendDN{})

@johnweldon does it probably make sense to have an extra "package" repository for not standard control types (MS ActiveDirectory, etc..). I dont think this kind of extension should be part of this reference lib.

[johnweldon]

@project0 I'm inclined to agree with you. How would you like that to look? Another repo in this org?

[rodrigc]

@project0 thanks for your example.

Microsoft documents many Extended Controls here: https://docs.microsoft.com/en-us/openspecs/windows_protocols/ms-adts/3c5e87db-4728-4f29-b164-01dd7d7391ea

@johnweldon Is there a generic way to implement an extended control using the current go-ldap code, or does the user of go-ldap need to implement their own:
• struct
• GetControlType() function
• Encode() function
• String() function

Thanks