The method to encrypt the user’s password: 0 (or "plain"): No encryption. Passwords are stored in plaintext. HIGHLY DISCOURAGED. 1 (or "Y"): Use crypt(3) function. 2 (or "mysql"): Use the MySQL PASSWORD() function. It is possible that the encryption function used by pam_mysql is different from that of the MySQL server, as pam_mysql uses the function defined in MySQL’s C-client API instead of using PASSWORD() SQL function in the query. 3 (or "md5"): Use plain hex MD5. 4 (or "sha1"): Use plain hex SHA1. 5 (or "drupal7"): Use Drupal7 salted passwords. 6 (or "joomla15"): Use Joomla15 salted passwords. 7 (or "ssha"): Use ssha hashed passwords. 8 (or "sha512"): Use sha512 hashed passwords. 9 (or "sha256"): Use sha256 hashed passwords.

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