perform multiple GET RESPONSE cycles if more data is available

So far we implemented only one round of "Send the APDU, get SW=61xx,
call GET RESPONSE".  This permitted us to receive only data up to 256
bytes.

Let's extend that to doing multiple rounds, concatenating the result.
This allows us to obtain arbitrary-length data from the card.

See Annex C.1 of ETSI TS 102 221 for examples showing multiple 61xx
iterations.

Change-Id: Ib17da655aa0b0eb203c29dc92690c81bd1300778
Closes: OS#6287
---
M pySim/transport/__init__.py
1 file changed, 23 insertions(+), 2 deletions(-)

diff --git a/pySim/transport/__init__.py b/pySim/transport/__init__.py
index e90ced6..2ffb9c3 100644
--- a/pySim/transport/__init__.py
+++ b/pySim/transport/__init__.py
@@ -137,11 +137,12 @@
         # xx is the number of response bytes available.
         # See also:
         if (sw is not None):
-            if ((sw[0:2] == '9f') or (sw[0:2] == '61')):
+            while ((sw[0:2] == '9f') or (sw[0:2] == '61')):
                 # SW1=9F: 3GPP TS 51.011 9.4.1, Responses to commands which are correctly executed
                 # SW1=61: ISO/IEC 7816-4, Table 5 — General meaning of the interindustry values of SW1-SW2
                 pdu_gr = pdu[0:2] + 'c00000' + sw[2:4]
-                data, sw = self.send_apdu_raw(pdu_gr)
+                d, sw = self.send_apdu_raw(pdu_gr)
+                data += d
             if sw[0:2] == '6c':
                 # SW1=6C: ETSI TS 102 221 Table 7.1: Procedure byte coding
                 pdu_gr = pdu[0:8] + sw[2:4]

