DATA-OBLIVIOUS COPYING FROM A FIRST ARRAY TO A SECOND ARRAY

摘要

Some embodiments are directed to a data retrieval device 210 for data-obliviously copying a subarray of a first array to a second array. The length of the second array is more than one and less than the length of the first array. The length of the subarray is at most the length of the second array. For each first element at a first index in the first array, the data retrieval device selects a second index in the second array for the first index in the first array; data-obliviously computes a choice bit indicative of whether to copy the first element to the second index in the second array; and replaces a second element at the second index in the second array by a replacement element, the replacement element being data-obliviously set to the first element or the second element based on the choice bit.