def invert(self, input):
'''Inverse of the shiftRows() method.
Input: <integer arrays> state
Output: <integer arrays> state (modified)
'''
output = []
for i in range(self.__nRows):
unshifted = _shift(input[i], -i)
self._debug_stream("row[%d] = %s -> %s" % (i, input[i], unshifted),
operation="invShiftRows")
output.append(unshifted)
return output
def do(self, input):
'''One of the round transformation methods.
cyclical left shift of the row 'i' of the state matrix by 'i'
positions s[r][c] = s[r][c+shift(r,nColumns) mod nColumns]
for 0<r<nRows and 0<=c<nColumns.
Input: <integer arrays> state
Output: <integer arrays> state (modified)
'''
output = []
for i in range(self.__nRows):
shifted = _shift(input[i], i)
self._debug_stream("row[%d] = %s -> %s" % (i, input[i], shifted),
operation="shiftRows")
output.append(shifted)
return output
