SCP02.py 文件源码

def wrapAPDU(self, apdu):
        """ Wrap APDU for SCP02, i.e. calculate MAC and encrypt.
Input APDU and output APDU are list of uint8. """
        lc = len(apdu) - 5
        assert len(apdu) >= 5, "Wrong APDU length: %d" % len(apdu)
        assert len(apdu) == 5 or apdu[4] == lc, \
            "Lc differs from length of data: %d vs %d" % (apdu[4], lc)

        cla = apdu[0]
        b8 = cla & 0x80
        if cla & 0x03 > 0 or cla & 0x40 != 0:
            # nonzero logical channel in APDU, check that are the same
            assert cla == self.CLA(False, b8), "CLA mismatch"
        sapdu = l2s(apdu)
        # CLA without log. channel can be 80 or 00 only
        if self.isCMAC:
            if self.i & M_CMAC_MODIF:  # CMAC on unmodified APDU
                mlc = lc
                clac = chr(b8)
            else:                      # CMAC on modified APDU
                mlc = lc + 8
                clac = chr(b8 + 0x04)
            mac = self.calcMAC_1d(clac + sapdu[1:4] + chr(mlc) + sapdu[5:])
            mac = [ord(x) for x in mac]
            if self.isENC:
                k = DES3.new(self.ses_ENC, DES.MODE_CBC, ZERO8)
                data = s2l(k.encrypt(pad80(sapdu[5:], 8)))
                lc = len(data)
            else:
                data = apdu[5:]
            lc += 8
            apdu = [self.CLA(True, b8)] + apdu[1:4] + [lc] + data + mac
        return apdu