Update rasn1 dependency for pkinit

Gemfile.lock

@@ -332,7 +332,8 @@ GEM
       thor (~> 1.0)
     rainbow (3.1.1)
     rake (13.0.6)
-    rasn1 (0.11.0)
+    rasn1 (0.12.0)
+      strptime (~> 0.2.5)
     rb-readline (0.5.5)
     recog (2.3.23)
       nokogiri
@@ -455,6 +456,7 @@ GEM
     sqlite3 (1.5.3)
       mini_portile2 (~> 2.8.0)
     sshkey (2.0.0)
+    strptime (0.2.5)
     swagger-blocks (3.0.0)
     thin (1.8.1)
       daemons (~> 1.0, >= 1.0.9)

lib/rex/proto/kerberos/model/pkinit.rb

@@ -40,7 +40,24 @@ module Rex
             end
 
             def to_der
-              self.options[:openssl_certificate].to_der
+              self.options[:openssl_certificate]&.to_der || ''
+            end
+
+            # RASN1 Glue method - Say if DER can be built (not default value, not optional without value, has a value)
+            # @return [Boolean]
+            # @since 0.12
+            def can_build?
+              !to_der.empty?
+            end
+
+            # RASN1 Glue method
+            def primitive?
+              false
+            end
+
+            # RASN1 Glue method
+            def value
+              options[:openssl_certificate]
             end
 
             def parse!(str, ber: false)

spec/lib/msf/core/exploit/remote/kerberos/client/pkinit_spec.rb

@@ -2,7 +2,6 @@
 require 'spec_helper'
 require 'rasn1'
 
-
 RSpec.describe Msf::Exploit::Remote::Kerberos::Client::Pkinit do
   subject do
     mod = ::Msf::Exploit.new