| 0,0 → 1,40 |
|---|
| """ crypto.keyedHash.tkip_mic |
| |
| A reference implementation of the TKIP Message Integrety Chek (MIC) |
| that is defined in IEEE 802.11i |
| |
| The MIC is based on Michael, a 64-bit MIC, with a design strength of 20 bits. |
| |
| (c) 2002 Paul A. Lambert |
| """ |
| from crypto.keyedHash.michael import Michael |
| |
| class TKIP_MIC(Michael): |
| """ The TKIP MIC Calculation for IEEE 802.11 TGi |
| This MIC algorithm uses the Michael Message Integrity Check (MIC) |
| and incorporates the DA, SA, priority and padding as |
| part of the MIC calculation |
| """ |
| def __init__(self, key=None, version='D3'): |
| """ """ |
| self.version = version |
| Michael.__init__(self,key) |
| |
| def hash(self, sa, da, priority, msduData ): |
| """ The TKIP MIC appends sa, da and priority to msduData |
| and uses the result in the Michael keyed hash |
| to create an 8 octet MIC value |
| """ |
| assert( 0 <= priority <= 15 ), 'Priority must be 4 bit value' |
| assert( (len(sa)==6) and (len(da)==6) ), 'Addresses must be 6 octets' |
| |
| if self.version == 'D3': |
| micData = da + sa + chr(priority) + 3*chr(0) + msduData |
| elif self.version == 'D2': |
| micData = da + sa + msduData |
| else: |
| raise 'bad version' |
| |
| return Michael.hash(self, micData) |
| |
| |