| ??? 07/14/12 03:29 Read: times |
#187928 - Checksum Responding to: ???'s previous message |
They probably had a checksum in the EEPROM too.
There aren't much need for extra security with the EEPROM since anyone who can get access to the electronics of a safe don't need to bother with any PIN code. The only open issue is what to do if you get a checksum error - in that case, the EEPROM cells could potentially even represent a PIN code that can't be entered with four normal digits. Another thing is that anything with just a 4-digit PIN has a rather low security class, so there really isn't a need to try too hard at security. But you should have a counter for number of PIN-code attempts, and after 3 errors refuse to process PIN codes for a long time - at least 10 minutes. And there must be no difference in behavior of the software until that fourth digit has been pressed. |
| Topic | Author | Date |
| Password in EEPROM | 01/01/70 00:00 | |
| Checksum | 01/01/70 00:00 | |
| 8-digit code | 01/01/70 00:00 | |
| Master Code | 01/01/70 00:00 | |
| So what does the requirements spec say? | 01/01/70 00:00 | |
| master codes .... | 01/01/70 00:00 | |
| This is a low-security lock - or no measly 4-digit PIN | 01/01/70 00:00 | |
| language | 01/01/70 00:00 | |
| just a thought | 01/01/70 00:00 | |
| Never give access when locked | 01/01/70 00:00 | |
| PIN + PUK | 01/01/70 00:00 | |
| The eeprom doesnt hold the password | 01/01/70 00:00 | |
High/low security | 01/01/70 00:00 |