正形置换在密码体制中应用广泛.基于GF(2^n)^m上的线性正形置换可用来设计分组密码的重要线性部件P置换.本文将GF(2)m上正形置换以及GF(2)m上完全平衡的概念推广到了GF(2^n)^m上,证明了GF(2^n)^m上的正形置换具有推广后的完全平衡性,证明了多项式环GF(q)[x]上的一个新结论,分析了GF(2^n)^m上线性正形置换的结构特点和计数,利用多项式环GF(q)[x]上的新结论给出了计数公式.
Orthomorphisms have important application in the design of cryptosystems.Linear orthomorphisms on GF(2^n)^m can be used to design the important linear part P-permutation in block cipher.This paper generalizes the orthomorphisms on GF(2)^m and the perfect balance on GF(2)^m to the ones on GF(2^n)^m by the first time,and proves that orthomorphisms on GF(2^n)^m are perfectly balanced,then proves a new theorem about GF(q)[x],and then designs the structure and counting method of linear orthomorphisms on GF(2^n)^m.At last it gives the formula for counting all the linear orthomorphisms on GF(2^n)^m by the new theorem about GF(q)[x].