| 摘要 |
<p>In a method for controlled program execution by a portable data carrier, the value of a status counter (ZZ) is altered during execution of each controlled section ( 36 .x) of an executed program ( 30 ) in order to reflect the processing of the respective controlled section ( 36 .x); when executing a jump instruction ( 42 .x), which causes one or more controlled sections ( 36 .x) to be skipped, the value of the status counter (ZZ) is altered as if the skipped controlled sections ( 36 .x) had been executed and the value of the status counter (ZZ) is compared at at least one test point ( 38 ) with at least one admissible value. A portable data carrier has corresponding features. The invention provides reliable protection against manipulations of the portable data carrier and is also suitable for application in executing complex programs.</p> |
