Implement InListPassiveTargets response parsing for ISO 14443 B

Implement PC/SC ATR generation for ISO 14443 B

1 files changed, 34 insertions, 16 deletions

diff --git a/readers.py b/readers.py
index 02940af..2dfc4ba 100644
--- a/readers.py
+++ b/readers.py
@@ -139,7 +139,8 @@ class ACR122_Reader(Smartcard_Reader):
     def __init__(self, parent):
         self._parent = parent
         self._name = self._parent.name+"-RFID"
-        self._last_ats = None
+        self._current_target = None
+        self._current_target_number = 0
     
     def pn532_transceive_raw(self, command):
         c_apdu = "\xff\x00\x00\x00" + chr(len(command)) + command
@@ -173,13 +174,14 @@ class ACR122_Reader(Smartcard_Reader):
         r = utils.PN532_Frame(response)
         r.parse_result(0)
         if len(r.targets) > 0:
-            self._last_ats = r.targets.values()[0].ats
+            self._current_target_number, self._current_target = r.targets.items()[0]
             return True
         else:
             response = self.pn532_transceive("\xd4\x4a\x01\x03\x00")
             r = utils.PN532_Frame(response)
             r.parse_result(3)
             if len(r.targets) > 0:
+                self._current_target_number, self._current_target = r.targets.items()[0]
                 return True
     
     def _internal_connect(self):
@@ -194,21 +196,37 @@ class ACR122_Reader(Smartcard_Reader):
     
     def get_ATR(self):
         # FIXME Properly implement for PC/SC version 2
-        if len(self._last_ats) == 0:
-            return "\x3b\x80\x80\x01\x01"
+        if self._current_target is None: return ""
+        
+        hist_bytes = []
+        
+        if self._current_target.type == utils.PN532_Target.TYPE_ISO14443A:
+            if len(self._current_target.ats) > 0:
+                # Quick and dirty: Extract historical bytes from ATS
+                ats = self._current_target.ats
+                if ats[0] > 1:
+                    interface_bytes = 0
+                    if ats[1] & 0x40: interface_bytes = interface_bytes + 1
+                    if ats[1] & 0x20: interface_bytes = interface_bytes + 1
+                    if ats[1] & 0x10: interface_bytes = interface_bytes + 1
+                    hist_bytes = ats[ (2+interface_bytes): ]
+                if len(hist_bytes) > 15: hist_bytes = hist_bytes[:15]
+            else:
+                return "\x3b\x80\x80\x01\x01"
+        elif self._current_target.type == utils.PN532_Target.TYPE_ISO14443B:
+            hist_bytes = self._current_target.atqb[5:9] + self._current_target.atqb[5:12]
+            if len(self._current_target.attrib_res) > 0:
+                hist_bytes.append(self._current_target.attrib_res[0] & 0xf0)
+            else:
+                hist_bytes.append(0)
         else:
-            # Quick and dirty: Extract historical bytes from ATS
-            hist_bytes = []
-            if self._last_ats[0] > 1:
-                interface_bytes = 0
-                if self._last_ats[1] & 0x40: interface_bytes = interface_bytes + 1
-                if self._last_ats[1] & 0x20: interface_bytes = interface_bytes + 1
-                if self._last_ats[1] & 0x10: interface_bytes = interface_bytes + 1
-                hist_bytes = self._last_ats[ (2+interface_bytes): ]
-            if len(hist_bytes) > 15: hist_bytes = hist_bytes[:15]
-            atr = [0x3b, 0x80 + len(hist_bytes), 0x80, 0x01] + hist_bytes
-            atr.append( reduce(lambda a,b: a ^ b, atr) ^ 0x3b )
-            return "".join(map(chr, atr))
+            return ""
+        
+        # The ISO 14443-4 A or -3 B code paths should have filled the hist_bytes list
+        atr = [0x3b, 0x80 + len(hist_bytes), 0x80, 0x01] + hist_bytes
+        atr.append( reduce(lambda a,b: a ^ b, atr) ^ 0x3b )
+        return "".join(map(chr, atr))
+
 
     def transceive(self, data):
         # FIXME Properly determine target number