| 摘要 |
A mobile wireless device programmed with software which provides a trusted user interface for the device by allowing the content of a secure screen memory to be modifiable only by authorised applications. Normally, the entire screen memory address is public information, making the entire screen memory fully available to any application; hence, even sensitive dialogs would use screen memory which can in theory be looked at by malicious software, enabling that malicious code to grab PIN data etc. or corrupt a trusted user interface. But with the present invention, unauthorised applications are prevented from accessing the data displayed by the secure frame buffer because they are able to access only the non-secure screen memory. Hence, malicious applications cannot retrieve data from a trusted dialog or compromise that data. Further, as the present invention is a software only solution, it requires no new hardware per se-the only requirement is that components (e.g. a software window server; a video chip etc.) can select content from different parts of screen memory-i.e. secure and non-secure frame buffers. |
