et99_softfull

首先对字母进行编号，小写字母a至z编号为1至26，大写字母A至Z分别编号27至52，这样每个字母都有唯一的一个序号，在发送内容时，我们以函数F(X)=X*X+X+1对发送字母的序号进行计算，就会获取个新的序号，对该序号再进行对52取余，该序号即为加密后的要发送字母的序号，这样就能达到加密的作用。(Number first letter lowercase letters a to z No. 1-26, No. 27-52 uppercase letters A to Z, respectively, so each letter has a unique serial number, sending content to the function F (X- ) = X* X+X+1 send letters number is calculated, it will get a new serial number, the serial number and then take the remainder of the 52, the serial number is the serial number of the letters to be sent encrypted, so that we can achieve encryption role.)

采用轮询机制，对数据库中数据进行加密处理(Using polling mechanism to encrypt data in database)

账号管理软件，高等级加密。功能简单，但安全等级高(Account management software, high-grade encryption)

DES、RSA、背包、AES、IDEA等各种加密算法的源码(All Kinds Of Encoding Algorithms)

支持加密Sqllite库，vs2008 + sqlite3 + sqlcipher,测试可用(Supports encryption Sqllite library, VS2008+ SQLite3+ sqlcipher, testing available)

RC4解加密算法生成DLL动态库，密钥可以再程序里面写死或者外部导入！(The RC4 the Xie encryption algorithm to generate the DLL dynamic libraries, key can re-program inside hardcoded or external import!)

SPN代换-置换算法的c实现，以及使用差分分析进行破解。(SPN substitution- replacement algorithm c implementation, and use of differential analysis to crack.)

ZipArchive，新增创建以及解压加密zip 文件_ZipArchive，精选ios编程学习源码，很好的参考资料。(ZipArchive, the new creation and extract the zip file encryption _ZipArchive, select learning IOS programming source code, a good reference.)

说明：  dsa数字签名 系统功能需求： 1.对文件进行签名，生成一个独立于原文的签名文件； 2.可以对文件进行签名，在文件后追加签名信息； 3.具有密钥管理的功能，比如密钥的生成、导入、导出； 4.可以对word文档实施操作，对word文档的内容进行签名； 5.能够比对已经实施的签名，防止进行重复的签名，以防止重放攻击； 6.可以对已经签名的文件进行单独的源文件和签名信息的分离操作。(DSA digital signature System functional requirements: 1. Sign the document and generate a signature file independent of the original text. 2. The document can be signed and the signature information can be added after the document. 3. It has the function of key management, such as key generation, import and export. 4. Word documents can be operated and the contents of Word documents can be signed. 5. Ability to compare existing signatures and prevent duplicate signatures to prevent replay attacks; 6. It is possible to separate the source file from the signature information of the signed file.)

基于DES的文件加密程序 采用ECB或CBC工作模式 DES算法核心代码(DES-based file encryption program using ECB or CBC mode of DES algorithm core code)