def insert_counter(self): """ TODO. """ smidr_long = bytes_to_long(self.smidr) smidr_long = (smidr_long & 0xFFFFFFFFFFFFFFE00000) | (self.tctr & 0x1FFFFF) self.smidr = long_to_bytes(smidr_long, __SMIDR_LEN)
def recvGCM(self):
m = ''
while True:
try:
m += self.conn.recv(4096)
except socket.error:
break
# prevents decryption of empty string
if not m:
return m
IV = crypto.bytes_to_long(m[:12])
ciphertext = m[12:-16]
tag = crypto.bytes_to_long(m[-16:])
return self.GCM.decrypt(IV, ciphertext, tag)
def new_key3(self): """ TODO. :Returns: TODO """ smidr_long = bytes_to_long(self.smidr[__SMIDR_OFF:]) # STRIP first 2 bytes from SMIDR value tmp1 = long_to_bytes(smidr_long | (self.shiftr & 0x1FFFFF), __DATALEN) # binary OR between shift register and SMIDR's right 8 bytes tmp2 = self.des_special(tmp1, self._fkr[self.key_ptr], True) # over ORed data is performed the OWF Key generation with currently pointed key on FKR bit_pos = self.search_bit(self.shiftr, __FKR_NUM, True) # Search bit position on shift register self._fkr[bit_pos] = tmp2[:self.keyslen] # Update key in FKR in selected slot (by shift register) return True
def tag1(self): """ TODO. :Returns: TODO """ if self.shiftr & self.tctr == 0: return # if AND check fails, return smidr_long = bytes_to_long(self.smidr[__SMIDR_OFF:]) # STRIP first 2 bytes from SMIDR value bitXorMask = ((self.shiftr - 1) & self.tctr) & 0x1FFFFF # Define BitXorMask tmp1 = long_to_bytes(smidr_long ^ bitXorMask, __DATALEN) # binary XOR between bitXorMask and SMIDR's right 8 bytes tmp2 = self.des_special(tmp1, self._fkr[self.key_ptr], True) # over XORed data perform OWF Key generation with currently pointed key on FKR self._fkr[self.key_ptr] = tmp2[:self.keyslen] # Update key in FKR for current key slot return True
def calculate_variants_for_3DESwithDUKPT(self, var_num): """ TODO. :Parameters: - *var\_num* (): TODO :Returns: TODO """ # This function does not set the last byte in the mask # It is useful for 3DES-CBC encryption with DUKPT with mask 3 and 4 mask = 0xff << ((__KEYSLEN_DES - var_num - 1) << 3) if self.keyslen == __KEYSLEN_3DES: mask = (mask << (__KEYSLEN_DES << 3)) | 0xff << ((__KEYSLEN_DES - var_num - 1) << 3) # Variant is calculated as XOR between current key and the PIN/MAC bitmask return long_to_bytes(mask ^ bytes_to_long(self._fkr[self.key_ptr]), self.keyslen)[-self.keyslen:]
def calculate_variants(self, var_num): """ TODO. :Parameters: - *var\_num* (): TODO :Returns: TODO """ # The following two lines are necessary if it is called before other requests (i.e.: after deriveKey) [MAYBE MUST BE A PRIVATE METHOD] # if not self.request_pin_entry1(): # return None mask = 0xff << ((__KEYSLEN_DES - var_num - 1) << 3) if self.keyslen == __KEYSLEN_3DES: mask = (mask << (__KEYSLEN_DES << 3)) | 0xff << ((__KEYSLEN_DES - var_num - 1) << 3) elif var_num == __VAR_MAC_OFF: mask |= 0xff # Variant is calculated as XOR between current key and the PIN/MAC bitmask return long_to_bytes(mask ^ bytes_to_long(self._fkr[self.key_ptr]), self.keyslen)[-self.keyslen:]
def calculate_variants_Nordic(self, var_num, type = 'IN'): """ TODO. :Parameters: - *var\_num* (): TODO - *type* (string): TODO :Returns: TODO """ mask = 0xff << ((__KEYSLEN_DES - var_num - 1) << 3) if type == 'OUT': mask |= 0xff if self.keyslen == __KEYSLEN_3DES: mask = (mask << (__KEYSLEN_DES << 3)) if type == 'IN': if self.keyslen == __KEYSLEN_DES: mask |= 0xff else: mask = (mask << (__KEYSLEN_DES << 3)) | 0xff << ((__KEYSLEN_DES - var_num - 1) << 3) # Variant is calculated as XOR between current key and the PIN/MAC bitmask return long_to_bytes(mask ^ bytes_to_long(self._fkr[self.key_ptr]), self.keyslen)[-self.keyslen:]