Portable data carrier having an operating error counter
View Patent ↗A method in a portable data carrier for safeguarding the data carrier against external attacks on the data carrier, wherein at least one counter is employed in the data carrier. A specified command is safeguarded such that it is executed by the data carrier only when the at least one counter lies in a specified values range. The at least one counter is decremented before an execution of the command and incremented only when the command has been executed without interruption. The at least one counter here is settable multiple times, in particular even after the issuance of the data carrier to a user.
1. A method in a portable data carrier having at least one counter, comprising the steps:
executing a specified command by the data carrier only when the at least one counter lies in a specified values range;
decrementing the at least one counter before an execution of the command and incrementing the at least one counter only when the command has been executed without interruption;
setting the at least one counter after an issuance of the data carrier to a user; and
setting the at least one counter with regard to a ratio of decrements of the at least one counter to increments of the at least one counter, said ratio being permissible for a specified time span.
2. The method according to claim 1 , including setting the at least one counter after a successful authentication to the data carrier.
3. The method according to claim 2 , including authenticating a user and/or a body issuing the data carrier by the user and/or body to the data carrier.
4. The method according to claim 1 , including carrying out setting of the at least one counter by a body issuing the data carrier.
5. The method according to claim 1 , including carrying out setting of the at least one counter by a user of the data carrier.
6. The method according to claim 1 , including providing more than one counter, a first counter being employed to safeguard a first command and a second counter being employed to safeguard a second command.
7. The method according to claim 6 , wherein the first counter safeguards a command that is executed in a first operating mode of the data carrier and the second counter safeguards a command that is executed in a second operating mode different from the first operating mode.
8. The method according to claim 1 , including setting the at least one counter with regard to an initial value starting out from which the at least one counter is decremented after the setting before an execution of the specified command.
9. The method according to claim 1 , wherein the at least one counter is set by the data carrier in dependence on those data that the data carrier ascertains itself.
10. The method according to a claim 1 , wherein the data carrier or at least the command that is safeguarded by the at least one counter is deactivated when the at least one counter leaves the specified values range.
11. A portable data carrier comprising at least one memory and a processor which is configured to execute a command stored in the memory, and at least one counter to safeguard the command,
the data carrier being configured to execute the command only when the at least one counter lies in a specified values range, and to decrement the at least one counter before an execution of the command and to increment it only when the command has been executed without interruption;
said at least one counter being arranged to be settable after an issuance of the data carrier to a user,
wherein the data carrier is configured to set the at least one counter with regard to a ratio of decrements of the at least one counter to increments of the at least one counter, said ratio being permissible for a specified time span.
12. The data carrier according to claim 11 , wherein the data carrier is configured to execute the steps of:
executing the command by the data carrier only when the at least one counter lies in the specified values range;
decrementing the at least one counter before the execution of the command and incrementing the at least one counter only when the command has been executed without interruption;
setting the at least one counter after the issuance of the data carrier to the user; and
setting the at least one counter with regard to the ratio of decrements of the at least one counter to increments of the at least one counter, said ratio being permissible for the specified time span.
13. The data carrier according to claim 11 , including a sensor that recognizes external influences on the data carrier and the data carrier is configured to set the at least one counter in dependence on those data that are ascertained by the sensor.