车机安全[基础]

Vehicle attack surface:

1. Indirect attack

   1. Adas(Advanced Driving Assistant System)

      • USB

      • Optical disk

   2. OBD[each vehicle has different obd]

      • OBD-II[introduce]

        • Interface

          • 12v 16needles

          • 24v 16needles

        • Communicate

          • SAE J1850 PWM

          • SAE J1850 VPW

          • ISO 9141-2

          • ISO 14230 KWP2000

          • ISO 15765 CAN

      • OBD can access engine ECU 

      • OBD can send command

      • OBD can modify ECU firmware

2. Short range attack

   1. Bluetooth

   2. Keyless Entry

   3. RFID(Radio Frequency Identification)

   4. TPMS(Tire Pressure Monitoring System)

   5. Wifi

   6. DSRC and V2X(Dedicated short range communication)

3. Remote wireless attack

   1. GPS

   2. FM

   3. Cellular

   4. 3G/4G/5G

Vehicle intranet introduce : FlexRay, MOST, CAN, LIN等

1. CAN

   1. High speed/rate CAN [125k bite - 1M/s ]

   2. Low speed/rate CAN [ 5 k bite - 125 bite/s ]

   3. CAN agreement feature

      1. Decentrailied [去中心]

      2. Adressing based on message [基于信息寻址]

      3. Bus Arbitration [总线仲裁]

         1. 隐态 [invisible/hidden] 

            1. Arbitrarily CAN node can access bus [任意can节点可以访问can总线]

         2. 显态 [visible]

            1. Just one, if have anther one, it need depend on priority [相同的can访问，需要根据优先级；所以这里会产生出dos问题]