TLV utilities

git-svn-id: svn+ssh://localhost/home/henryk/svn/cyberflex-shell/trunk@55 f711b948-2313-0410-aaa9-d29f33439f0b

TLV_utils.py

@@ -0,0 +1,68 @@
+import binascii, utils
+
+context_FCP = object()
+context_FMD = object()
+context_FCI = object()
+recurse = object()
+binary = object()
+number = object()
+ascii = object()
+
+tags = {
+    None: {
+        0x62: (recurse, "File Control Parameters", context_FCP),
+        0x64: (recurse, "File Management Data", context_FMD),
+        0x6F: (recurse, "File Control Information", context_FCI),
+        0x80: (number, "Number of data bytes in the file, excluding structural information"),
+        0x81: (number, "Number of data bytes in the file, including structural information"),
+        0x82: (binary, "File descriptor byte"),
+        0x83: (binary, "File identifier"),
+        0x84: (binary, "DF name"),
+        0x85: (binary, "Proprietary information"),
+        0x86: (binary, "Security attributes"),
+        0x87: (binary, "Identifier of an EF containing an extension of the FCI"),
+    },
+}
+
+def tvl_unpack(data):
+    tag = ord(data[0])
+    length = ord(data[1])
+    value = data[2:(2+length)]
+    rest = data[(2+length):]
+    
+    return tag, length, value, rest
+
+def decode(data, context = None, level = 0):
+    result = []
+    while len(data) > 0:
+        tag, length, value, data = tvl_unpack(data)
+        
+        interpretation = tags.get(context, tags.get(None, {})).get(tag, (binary, "Unknown"))
+        current = ["\t"*level]
+        current.append("Tag 0x%02X, Len 0x%02X, '%s':" % (tag, length, interpretation[1]))
+        
+        if interpretation[0] is recurse:
+            current.append("\n")
+            current.append( decode(value, interpretation[2], level+1) )
+        elif interpretation[0] is number:
+            num = 0
+            for i in value:
+                num = num * 256
+                num = num + ord(i)
+            current.append( " 0x%02x (%i)" % (num, num))
+        elif interpretation[0] is ascii:
+            current.append( " %s" % value)
+        elif interpretation[0] is binary:
+            current.append( " %s" % utils.hexdump(value, short=True))
+        
+        result.append( "".join(current) )
+    
+    return "\n".join(result)
+
+if __name__ == "__main__":
+    test = binascii.unhexlify("".join(("6f 2b 83 02 2f 00 81 02 01 00 82 03 05 41 26 85" \
+        +"02 01 00 86 18 60 00 00 00 ff ff b2 00 00 00 ff" \
+        +"ff dc 00 00 00 ff ff e4 10 00 00 ff ff").split()))
+    
+    decoded = decode(test)
+    print decoded

cards/generic_card.py

@@ -20,7 +20,6 @@ class Card:
     STATUS_WORDS = { 
         SW_OK: "Normal execution",
         '61??': "%(SW2)i (0x%(SW2)02x) bytes of response data can be retrieved with GetResponse.",
-        '6700': "Wrong length",
         '6C??': "Bad value for LE, 0x%(SW2)02x is the correct value.",
         '63C?': lambda SW1,SW2: "The counter has reached the value '%i'" % (SW2%16)
     }
@@ -37,6 +36,7 @@ class Card:
         self._i = 0
         self.last_apdu = None
         self.last_sw = None
+        self.last_result = None
         self.sw_changed = False
     
     def verify_pin(self, pin_number, pin_value):
@@ -95,6 +95,7 @@ class Card:
             print "Ending transaction %i\n%s\n" % (self._i, '-'*80)
         self._i = self._i + 1
         
+        self.last_result = result
         return result
     
     def can_handle(cls, card):

utils.py

@@ -292,21 +292,6 @@ class R_APDU(APDU):
         "Return this APDU as a binary string"
         return self.data + self.sw
     
-
-class TPDU:
-    "Base class for TPDUs"
-    
-    def __init__(self, apdu):
-        self.apdu = apdu
-    
-class TPDU_T0(TPDU):
-    "Class for a T=0 TPDU"
-    protocol = 0
-
-class TPDU_T1(TPDU):
-    "Class for T=1 TPDU"
-    protocol = 1
-    
 if __name__ == "__main__":
     response = """
 0000:  07 A0 00 00 00 03 00 00 07 00 07 A0 00 00 00 62  ...............b