Introduction to Simulation information encryption flowchart

The Encryption_demo code simulates the flowchart content of Tuyi and figure II, but only simulates, not what application, its application process is limited to the transfer process between the programs, does not involve the data transmission between the network, so just simulates its process.

Figure one information encryption flowchart with security authentication

Figure II Information decryption process diagram using Security authentication technology

Figure III Using security-certified Information encryption Flowchart text description

Figure Four text description of the information decryption process diagram using Security authentication technology

There's nothing new about Encryption_demo code. The purpose of the release is to enable you to understand the "use of security-certified information Encryption Flowchart" of the operation process. Code, you can download and take a look. The next thing I want to say is that the most important work is reflected in the calculation of the offset of the byte array. For example, in this program using MD5 hash, its hash value fixed length 16 bytes, using DES algorithm group encryption, its key and iv bytes are 8 bytes; signed with RSA, signature length fixed to 128 bytes, and the length of the encryption results, we want to encrypt the length of the byte array is 128+8 +8 = 144, the number of bytes after RSA asymmetric encryption is 1152 bytes long. So, in the first flowchart, the entire ciphertext byte length we know is not fixed, but the length of the first and third parts is fixed (again, we use the DES block encryption algorithm, MD5 hash function, RSA method signature and encryption, The following analysis results are also based on this. Like what: