Add support for ldapwhoami (RFC4532) (now with tests)

lib/net/ldap.rb

@@ -325,7 +325,7 @@ class Net::LDAP
 
   universal = {
     constructed: {
-      107 => :array, #ExtendedResponse (PasswdModifyResponseValue)
+      107 => :string, # ExtendedResponse
     },
   }
 
@@ -341,6 +341,7 @@ class Net::LDAP
 
   StartTlsOid = '1.3.6.1.4.1.1466.20037'
   PasswdModifyOid = '1.3.6.1.4.1.4203.1.11.1'
+  WhoamiOid = '1.3.6.1.4.1.4203.1.11.3'
 
   # https://tools.ietf.org/html/rfc4511#section-4.1.9
   # https://tools.ietf.org/html/rfc4511#appendix-A
@@ -1200,6 +1201,23 @@ def delete_tree(args)
     end
   end
 
+  # Return the authorization identity of the client that issues the
+  # ldapwhoami request.  The method does not support any arguments.
+  #
+  # Returns True or False to indicate whether the request was successfull.
+  # The result is available in the extended status information when calling
+  # #get_operation_result.
+  #
+  #  ldap.ldapwhoami
+  #  puts ldap.get_operation_result.extended_response
+  def ldapwhoami(args = {})
+    instrument "ldapwhoami.net_ldap", args do |payload|
+      @result = use_connection(args, &:ldapwhoami)
+      @result.success? ? @result.extended_response : nil
+    end
+  end
+  alias_method :whoami, :ldapwhoami
+
   # This method is experimental and subject to change. Return the rootDSE
   # record from the LDAP server as a Net::LDAP::Entry, or an empty Entry if
   # the server doesn't return the record.

lib/net/ldap/connection.rb

@@ -703,6 +703,22 @@ def delete(args)
     pdu
   end
 
+  def ldapwhoami
+    ext_seq = [Net::LDAP::WhoamiOid.to_ber_contextspecific(0)]
+    request = ext_seq.to_ber_appsequence(Net::LDAP::PDU::ExtendedRequest)
+
+    message_id = next_msgid
+
+    write(request, nil, message_id)
+    pdu = queued_read(message_id)
+
+    if !pdu || pdu.app_tag != Net::LDAP::PDU::ExtendedResponse
+      raise Net::LDAP::ResponseMissingOrInvalidError, "response missing or invalid"
+    end
+
+    pdu
+  end
+
   # Internal: Returns a Socket like object used internally to communicate with
   # LDAP server.
   #

lib/net/ldap/pdu.rb

@@ -194,13 +194,13 @@ def parse_ldap_result(sequence)
   #           requestValue     [1] OCTET STRING OPTIONAL }
 
   def parse_extended_response(sequence)
-    sequence.length >= 3 or raise Net::LDAP::PDU::Error, "Invalid LDAP result length."
+    sequence.length.between?(3, 5) or raise Net::LDAP::PDU::Error, "Invalid LDAP result length."
     @ldap_result = {
       :resultCode => sequence[0],
       :matchedDN => sequence[1],
       :errorMessage => sequence[2],
     }
-    @extended_response = sequence[3]
+    @extended_response = sequence.last
   end
   private :parse_extended_response
 

test/test_ldap_connection.rb

@@ -574,4 +574,15 @@ def test_search_with_controls
     # ensure no unread
     assert unread.empty?, "should not have any leftover unread messages"
   end
+
+  def test_ldapwhoami
+    ber = Net::BER::BerIdentifiedArray.new([Net::LDAP::ResultCodeSuccess, '', '', 0, 'dn:uid=zerosteiner,ou=users,dc=example,dc=org'])
+    ber.ber_identifier = Net::LDAP::PDU::ExtendedResponse
+    response = [1, ber]
+
+    @tcp_socket.should_receive(:read_ber).and_return(response)
+
+    result = @connection.ldapwhoami
+    assert result.extended_response == 'dn:uid=zerosteiner,ou=users,dc=example,dc=org'
+  end
 end