A start at pythoncardx.framework.tlv. Note toBytes: the function both…

… static and not static !

pythoncardx/framework/tlv/__init__.py

@@ -1,4 +1,4 @@
-from javacard.framework import CardRuntimeException
+from pythoncard.framework import CardRuntimeException
 
 class TLVException(CardRuntimeException):
  EMPTY_TAG = 0
@@ -13,6 +13,8 @@ class TLVException(CardRuntimeException):
  TLV_LENGTH_GREATER_THAN_32767 = 9
  TLV_SIZE_GREATER_THAN_32767 = 10
 
-from pythoncard.framework.tlv import bertag
+from pythoncardx.framework.tlv import bertag
 
 BERTag = bertag.BERTag
+PrimitiveBERTag = bertag.PrimitiveBERTag
+ConstructedBERTag = bertag.ConstructedBERTag

pythoncardx/framework/tlv/bertag.py

@@ -1,6 +1,11 @@
-"""
-It's 2.2 ... not that prioritary ...
-"""
+from pythoncardx.framework.tlv import TLVException
+
+class toBytes(object):
+ def __get__(self, obj, objtype=None):
+ if obj is not None:
+ return obj._toBytesBound
+ else:
+ return BERTag._toBytesStatic
 
 class BERTag(object):
  BER_TAG_CLASS_MASK_APPLICATION = 0
@@ -11,16 +16,87 @@ class BERTag(object):
  BER_TAG_TYPE_PRIMITIVE = 5
 
  def __init__(self):
- self._tag = 0
- self._length = 0
- self._value = []
-
- def equals(self, otherTag):
- pass
-
- @classmethod
- def getInstance(classs, bArray, bOff):
- c = classs()
- c.init(bArray, bOff)
- return c
+ self._tagClass = 0
+ self._tagNumber = 0
+
+ def init(self, bArray, bOff):
+ self._tagClass = bArray[bOff] >> 6
+ if (bArray[bOff] & 0x1f) == 0x1f:
+ self._tagNumber = 0
+ bOff += 1
+ while (bArray[bOff] & 0x80) == 0x80:
+ self._tagNumber = self._tagNumber << 7
+ self._tagNumber += bArray[bOff] & 0x7f
+ bOff += 1
+ self._tagNumber = self._tagNumber << 7
+ self._tagNumber += bArray[bOff] & 0x7f
+ else:
+ self._tagNumber = bArray[bOff] & 0x1f
+
+ def _toBytesBound(self, outBuf, bOffset):
+ outBuf[bOffset] = self._tagClass << 6
+ outBuf[bOffset] += self._PC << 5
+ if self._tagNumber <= 30:
+ outBuf[bOffset] += self._tagNumber
+ return 1
+ else:
+ tagNumber = self._tagNumber
+ outBuf[bOffset] += 0x1f
+ chunks = []
+ while tagNumber > 0:
+ chunks.append(tagNumber & 0x7f)
+ tagNumber = tagNumber >> 7
+ bLen = 1
+ for i in reversed(chunks):
+ outBuf[bOffset+bLen] = 0x80
+ outBuf[bOffset+bLen] += i
+ bLen += 1
+ #clear the high bit on the last part
+ outBuf[bOffset+bLen-1] &= 0x7f
+ return bLen
+
+ @staticmethod
+ def _toBytesStatic(tagClass, isConstructed, tagNumber, outArray, bOff):
+ tag = {True: ConstructedBERTag,
+ False: PrimitiveBERTag}[isConstructed]()
+ tag.init(tagClass, tagNumber)
+ return tag.toBytes(outArray, bOff)
+
+ toBytes = toBytes()
+
+class PrimitiveBERTag(BERTag):
+ def __init__(self):
+ BERTag.__init__(self)
+ self._PC = 0 # primitive
+
+ def init(self, param1, param2):
+ self._tagClass = None
+ self._tagNumber = None
+ if isinstance(param1, list):
+ if (param1[param2] & 0x20) == 0x20:
+ # constructed tag
+ raise TLVException(TLVException.MALFORMED_TAG)
+ BERTag.init(self, param1, param2)
+ else:
+ tagClass = param1
+ tagNumber = param2
+ self._tagClass = tagClass
+ self._tagNumber = tagNumber
+
+class ConstructedBERTag(BERTag):
+ def __init__(self):
+ BERTag.__init__(self)
+ self._PC = 1 # constructed
+
+ def init(self, param1, param2):
+ self._tagClass = None
+ self._tagNumber = None
+ if isinstance(param1, list):
+ if (param1[param2] & 0x20) == 0:
+ # primitive tag
+ raise TLVException(TLVException.MALFORMED_TAG)
+ BERTag.init(self, param1, param2)
+ else:
+ self._tagClass = param1
+ self._tagNumber = param2
 

test/testTLVTag.py

@@ -0,0 +1,15 @@
+import unittest
+
+from pythoncardx.framework.tlv import BERTag, PrimitiveBERTag, ConstructedBERTag
+
+class BERTagTest(unittest.TestCase):
+
+ def testtoBytes(self):
+ array = [0 for i in xrange(10)]
+ self.assertEquals(1, BERTag.toBytes(1, False, 5, array, 0))
+ self.assertEquals(0x45, array[0])
+
+ self.assertEquals(3, BERTag.toBytes(1, False, 0x3fff, array, 0))
+ self.assertEquals(0x5f, array[0])
+ self.assertEquals(0xff, array[1])
+ self.assertEquals(0x7f, array[2])