Detailed explanation of php MD5 encryption

mysql＞CREATE TABLE members (
-＞username CHAR(14) NOT NULL,
-＞password CHAR(32) NOT NULL,
-＞PRIMARY KEY(username)
-＞);

Then, we can enter the user’s data into the table: Username Password Tom keloD1C377lKE John ba1T7vnz9AWgk Bill paLUvRWsRLZ4U

The plain codes corresponding to these encrypted passwords are Tom, John and Bill respectively. We will create a jam string based on the first two letters of the password:

＜?php
$enteredPassword.
$salt = substr($enteredPassword, 0, 2);
$userPswd = crypt($enteredPassword, $salt);
// $userPswd is then combined with the username Stored together in MySQL
crypt() and Apache's password-response verification system application

$host = "localhost"; //Host
$username = "Tom"; //Username
$passwd = "Hello world "; //Password
$db = "users"; //Database name
// Set whether to pass the verification flag, the default is no
$authorization = 0;
// Prompt the user to enter the account and password
if (isset($ PHP_AUTH_USER) && isset($PHP_AUTH_PW)){
　mysql_pconnect($host, $username, $passwd) or die("Cannot connect to the MySQL server!");
　mysql_select_db($db) or die("Cannot select database!" ; username = '$PHP_AUTH_USER' AND password = '$encrypted_pswd'";
　　 // Execute query
　if (mysql_numrows(mysql_query($query)) == 1) {
$authorization = 1;
　　}
}
if (! $authorization){
　header('WWW-Authenticate: Basic realm="User Authentication"');
header('HTTP/1.0 401 Unauthorized');
print "Unable to pass verification";
exit;
}else {
 print "Encrypted";
}
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The function encrypted by MD5 in PHP is md5(), one of its functions is mixing.

A hash function can transform a variable-length message into a fixed-length hashed output, also known as a "message digest". This is very useful because a fixed-length string can be used Check file integrity and verify digital signatures and user identities. PHP's built-in md5() hash function will convert a variable-length message into a 128-bit (32-character) message digest. An interesting feature of mixed encoding is that the original plain code cannot be obtained by analyzing the mixed information, because the mixed result has no dependence on the original plain code content. Even changing only one character in a string will cause the MD5 hybrid algorithm to calculate two completely different results. Let’s first look at the contents of the table below and its corresponding results:

Use md5() to mix strings

＜php

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＜?php

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