Patent ID: 7475431

Claim:
A computer-implemented process comprising: determining a first security level of a caller code unit identified in a call stack; determining if a required permission maps to a second security level, wherein the required permission is associated with a desired code unit to be executed; in response to a determination that the required permission maps to the second security level, performing the following: determining if the second security level is higher than the first security level; in response to determined that the second security level is not higher than the first security level, executing the desired code unit; in response to determined that the second security level is higher than the first security level, performing the following: examining each of a plurality of individual permissions, the plurality of individual permissions associated with the caller code unit, to determine whether one of the individual permissions permits the caller code unit to execute the desired code unit; and executing the desired code unit in response to a determination that one of the individual permissions permits the caller code unit to execute the desired code unit; and in response to a determination that the required permission does not map to the second security level, performing the following: examining each of the plurality of individual permissions associated with the caller code unit, to determine whether one of the individual permissions permits the caller code unit to execute the desired code unit; and executing the desired code unit in response to a determination that one of the individual permissions permits the caller code unit to execute the desired code unit.