MD5的全称是Message-digest Algorithm 5（信息-摘要算法），用于确保信息传输完整一致。在90年代初由MIT Laboratory for Computer Science和RSA Data Security Inc,的Ronald L. Rivest开发出来，经MD2、MD3和MD4发展而来。它的作用是让大容量信息在用数字签名软件签署私人密钥前被"压缩"成一种保密的格式（就是把一个任意长度的字节串变换成一定长的大整数）。不管是MD2、MD4还是MD5，它们都需要获得一
sha碰撞,MD5碰撞实现，#!/usr/local/bin/perl # It was noted that Intel IA-32 C compiler generates code which # performs ~30% *faster* on P4 CPU than original *hand-coded* # SHA1 assembler implementation. To address this problem (and # prove that humans are s
