MD5 & MD5 salt value encryption

Introduction and features

Md5

• Message Digest algorithm 5, Information digest algorithm
• compressibility ： Any length of data , To calculate the Md5 The length of the value is fixed ;
• Easy to calculate ： From the original data Md5 Value is easily ;
• Resistance to change ： Make any changes to the source data , Even if only one byte is modified , What you get MD5 Value is easily .
• Strong impact resistance ： I want to find two different data , Make them have the same Md5 value , It's very difficult .

Add salt

• By generating random numbers and Md5 Generating strings to combine
• The database also stores Md5 Value jade salt value , Verify the correctness of using salt Conduct Md5 that will do .

Use recommend BCryptPasswordEncoder

@Test
   public void md5Test() {
    

       //org.apache.commons.codec.digest
       //  Due to resistance to modification   So it can be violent   Crack   Rainbow watch   therefore MD5 Direct encryption is not possible 
       DigestUtils.md5Hex("123456");
       //  Salt value encryption : Random value   Format  $1$+8 Bit character 
       // For example, add the current system time   For subsequent verification, you need to save the system time   You can encrypt the comparison again during verification 
       Md5Crypt.md5Crypt("123456".getBytes(),"$1$88888888");

       //  Coder  springsecurity  We no longer need to store salt value , Matching will automatically resolve the salt value 
       BCryptPasswordEncoder bCryptPasswordEncoder = new BCryptPasswordEncoder();
       // code   Different every time 
       String encode = bCryptPasswordEncoder.encode("123456");
       // Verify the match 
       bCryptPasswordEncoder.matches("123456",encode);

   }

Author's statement

 If there is a problem , Welcome to correct ！