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      1 # CER encoder
      2 from pyasn1.type import univ
      3 from pyasn1.codec.ber import encoder
      4 from pyasn1.compat.octets import int2oct, null
      5 
      6 class BooleanEncoder(encoder.IntegerEncoder):
      7     def encodeValue(self, encodeFun, client, defMode, maxChunkSize):
      8         if client == 0:
      9             substrate = int2oct(0)
     10         else:
     11             substrate = int2oct(255)
     12         return substrate, 0
     13 
     14 class BitStringEncoder(encoder.BitStringEncoder):
     15     def encodeValue(self, encodeFun, client, defMode, maxChunkSize):
     16         return encoder.BitStringEncoder.encodeValue(
     17             self, encodeFun, client, defMode, 1000
     18             )
     19 
     20 class OctetStringEncoder(encoder.OctetStringEncoder):
     21     def encodeValue(self, encodeFun, client, defMode, maxChunkSize):
     22         return encoder.OctetStringEncoder.encodeValue(
     23             self, encodeFun, client, defMode, 1000
     24             )
     25 
     26 # specialized RealEncoder here
     27 # specialized GeneralStringEncoder here
     28 # specialized GeneralizedTimeEncoder here
     29 # specialized UTCTimeEncoder here
     30 
     31 class SetOfEncoder(encoder.SequenceOfEncoder):
     32     def encodeValue(self, encodeFun, client, defMode, maxChunkSize):
     33         if isinstance(client, univ.SequenceAndSetBase):
     34             client.setDefaultComponents()
     35         client.verifySizeSpec()
     36         substrate = null; idx = len(client)
     37         # This is certainly a hack but how else do I distinguish SetOf
     38         # from Set if they have the same tags&constraints?
     39         if isinstance(client, univ.SequenceAndSetBase):
     40             # Set
     41             comps = []
     42             while idx > 0:
     43                 idx = idx - 1
     44                 if client[idx] is None:  # Optional component
     45                     continue
     46                 if client.getDefaultComponentByPosition(idx) == client[idx]:
     47                     continue
     48                 comps.append(client[idx])
     49             comps.sort(key=lambda x: isinstance(x, univ.Choice) and \
     50                                      x.getMinTagSet() or x.getTagSet())
     51             for c in comps:
     52                 substrate += encodeFun(c, defMode, maxChunkSize)
     53         else:
     54             # SetOf
     55             compSubs = []
     56             while idx > 0:
     57                 idx = idx - 1
     58                 compSubs.append(
     59                     encodeFun(client[idx], defMode, maxChunkSize)
     60                     )
     61             compSubs.sort()  # perhaps padding's not needed
     62             substrate = null
     63             for compSub in compSubs:
     64                 substrate += compSub
     65         return substrate, 1
     66 
     67 tagMap = encoder.tagMap.copy()
     68 tagMap.update({
     69     univ.Boolean.tagSet: BooleanEncoder(),
     70     univ.BitString.tagSet: BitStringEncoder(),
     71     univ.OctetString.tagSet: OctetStringEncoder(),
     72     univ.SetOf().tagSet: SetOfEncoder()  # conflcts with Set
     73     })
     74 
     75 typeMap = encoder.typeMap.copy()
     76 typeMap.update({
     77     univ.Set.typeId: SetOfEncoder(),
     78     univ.SetOf.typeId: SetOfEncoder()
     79     })
     80 
     81 class Encoder(encoder.Encoder):
     82     def __call__(self, client, defMode=0, maxChunkSize=0):
     83         return encoder.Encoder.__call__(self, client, defMode, maxChunkSize)
     84 
     85 encode = Encoder(tagMap, typeMap)
     86 
     87 # EncoderFactory queries class instance and builds a map of tags -> encoders
     88