ECB模式，CBC模式DES加解密。

1.CBC模式与一般的不一样，当密文的数据发生错误时，解密后错误字节块和后续所有块的所有字节都是错误的。而一般模式只会影响当前块和后续块的相应字节。



2.可以加密任意长度的数据文件，最后的块数据不足8bytes,不是简单的补0。补0的缺陷是当明文块尾数据为0时，在解密时就不知如何处理了。



3.编译命令：

1. 编译测试程序 make test.

2. 编译动态库 make libdes.so

3. 编译静态库 make libdes.a-ECB mode, CBC mode DES encryption and decryption.

1.CBC mode and the general not the same, when the ciphertext data error occurs, the decrypted error byte block and all subsequent blocks all bytes are wrong. The general pattern affects only the current block and the corresponding byte subsequent blocks.



2. You can encrypt the data files of any length, the last block to insufficient data 8bytes, not simply fill 0. Fill zeros when plaintext block end data is 0, when I do not know how to handle the decryption.



3. Compile command:

1. Compile the test program make test.

2. Compile the DLL make libdes.so

3. Compile the static library make libdes.a