Too much fun with ASN.1

svn path=/scripts/rpki/manifest.py; revision=1149

1 files changed, 36 insertions, 3 deletions

diff --git a/scripts/rpki/manifest.py b/scripts/rpki/manifest.py
index 51755732..65ffd399 100644
--- a/scripts/rpki/manifest.py
+++ b/scripts/rpki/manifest.py
@@ -22,14 +22,47 @@ class FilesAndHashes(SequenceOf):
 
 class Manifest(Sequence):
   def __init__(self, optional=0, default=''):
-    self.version        = Integer(0, "AgEA")
-    #self.version        = Integer()
+
+    # I'm having trouble decoding the ASN.1 as currently specified.
+    # I've asked about this on the mailing list, but I see three
+    # options:
+    #
+    # 1) What the spec currently says, which doesn't quite work.
+    #
+    # 2) Get rid of the default on the version field, which might
+    #    make sense as it doesn't waste a lot of space.
+    #
+    # 3) Explictly tag the version field, which seems to be the usual
+    #    ASN.1 thing to do in these situations.
+    #
+    # Until the mailing list settles this, I've included code for all
+    # three options here, using the numbers above.
+    #
+    # Clean all this up once the mailing list settles it.
+
+    which_option = 1
+
+    if which_option == 1:
+      self.version      = Integer(0, "AgEA")
+
+    if which_option in (2, 3):
+      self.version      = Integer()      
+
+    if which_option == 3:
+      self.explicitVersion = Explicit(CLASS_CONTEXT, FORM_CONSTRUCTED, 0, self.version, 0, 'oAMCAQA=')
+
     self.manifestNumber = Integer()
     self.thisUpdate     = GeneralizedTime()
     self.nextUpdate     = GeneralizedTime()
     self.fileHashAlg    = Oid()
     self.fileList       = FilesAndHashes()
-    contents = [ self.version,
+
+    if which_option in (1, 2):
+      contents = [ self.version ]
+    else:
+      contents = [ self.explicitVersion ]
+
+    contents += [
                  self.manifestNumber,
                  self.thisUpdate,
                  self.nextUpdate,