Mysqli access denied , using UNIX socket

Question

I am trying to learn PHP, and I am setting up the database connection.
On Mysql Workbench, I created a database called php, and created a table. Then I created the account "sam"@"localhost",(I am using Ubuntu desktop, and sam is the output of whoami ) with auth_socket, Granted ALL on . , and when I press ctrl+alt+T and input mysql and press enter , I can successfully login.
Now I followed https://www.php.net/manual/en/mysqli.quickstart.connections.php , and tried using socket, I failed.

2021/08/13 16:54:35 [error] 1363#1363: *11 FastCGI sent in stderr: "PHP message: PHP Warning:  mysqli::__construct(): (HY000/1698): Access denied for user 'sam'@'localhost' in /var/www/php/my2.php on line 3PHP message: PHP Warning:  main(): Couldn't fetch mysqli in /var/www/php/my2.php on line 5" while reading response header from upstream, client: 127.0.0.1, server: _, request: "GET /my2.php HTTP/1.1", upstream: "fastcgi://unix:/var/run/php/php7.4-fpm.sock:", host: "localhost:803"

And here is my code. <?php

$mysqli = new mysqli("localhost", "sam", Null, "php");

echo $mysqli->host_info . "\n";

The output is nothing in a browser.

Then I tried this.

<html>
   <head>
      <title>Connecting MySQL Server</title>
   </head>
   <body>
      <?php
         $dbhost = 'localhost';
         $dbuser = 'sam';
         //$dbpass = 'root@123';
         $mysqli = new mysqli($dbhost, $dbuser,NULL,NULL,NULL,"/run/mysqld/mysqld.sock");
         
         if($mysqli->connect_errno ) {
            printf("Connect failed: %s<br />", $mysqli->connect_error);
            exit();
         }
         printf('Connected successfully.<br />');
         $mysqli->close();
      ?>
   </body>
</html>

The output is Connect failed: Access denied for user 'sam'@'localhost'
With log

2021/08/13 16:59:17 [error] 1363#1363: *13 FastCGI sent in stderr: "PHP message: PHP Warning:  mysqli::__construct(): (HY000/1698): Access denied for user 'sam'@'localhost' in /var/www/php/mysqli.php on line 10" while reading response header from upstream, client: 127.0.0.1, server: _, request: "GET /mysqli.php HTTP/1.1", upstream: "fastcgi://unix:/var/run/php/php7.4-fpm.sock:", host: "localhost:803"

I don't have password for user sam on mysql.

MariaDB [mysql]> select user,password from user;
+-----------+-------------------------------------------+
| user      | password                                  |
+-----------+-------------------------------------------+
| root      |                                           |
| someone   | *2470C0C06DEE42FD1618BB99005ADCA2EC9D1E19 |
| someone   | *9B8A3238012965AC630589D859535EA0B7C231A7 |
| someone   | *AF411B6C73B3AC3A2316A309A71758175CC14FEE |
| someone   | *D76A454D84260E84578F09915624F275F3D0E08B |
| sam       |                                           |
+-----------+-------------------------------------------+
6 rows in set (0.001 sec)

I changed the actrual username to someone to protect privacy. You can see that sam have no password.

score 0 · Accepted Answer · answered Aug 13 '21 at 09:21

0

Use your Mysql Workbench to set a password for the user sam and use that password for connecting with the mysqli library. I don't know if Mysql Workbench does have a click-through option to do so, if not or if you prefer the SQL way, use something like:

CREATE USER 'sam'@'localhost' IDENTIFIED BY 'choose_a_safe_password'

answered Aug 13 '21 at 09:21

xogoxec344

36
5

What if I want to use password-less? I learnt that more passwords means more risk. Besides, the password will be in plain_text in php. Is there an option to omit password in my php? – Sam Aug 16 '21 at 03:30
I don't know about mysql auth without password. Could you explain why you think "more passwords mean more risk"? Where did you learn that? I strongly disagree. – xogoxec344 Aug 16 '21 at 21:06
have a look at https://www.percona.com/blog/2019/11/01/use-mysql-without-a-password/ -> use `IDENTIFIED VIA unix_socket;` instead of a password and a linux user with the same name can connect without specifying a password. – xogoxec344 Aug 16 '21 at 21:10
You use ssh instead of a password, and ssh keys are prior to passphrases. – Sam Aug 18 '21 at 02:03
how you secure your ssh connection is completely independent of how you connect to mysql from a php script running on the same machine. – xogoxec344 Aug 18 '21 at 19:29
Thanks, I see now. Maybe I should put my brain into the microwave. Haha – Sam Aug 23 '21 at 13:28

Mysqli access denied , using UNIX socket

1 Answers1