Add notes about sudo setup (#1490203)

plugins/password/README

@@ -46,6 +46,7 @@
  2.20. Plesk (Plesk RPC-API)
  2.21. Kpasswd
  3. Driver API
+ 4. Sudo setup
 
 
  1. Configuration
@@ -348,3 +349,17 @@
  PASSWORD_CRYPT_ERROR, PASSWORD_ERROR when driver was unable to change password.
  Extended result (as a hash-array with 'message' and 'code' items) can be returned
  too. See existing drivers in drivers/ directory for examples.
+
+ 4. Sudo setup
+ -------------
+
+ Some drivers that execute system commands (like chpasswd) require use of sudo command.
+ Here's a sample for CentOS 7:
+
+ # cat <<END >/etc/sudoers.d/99-roundcubemail
+ apache ALL=NOPASSWD:/usr/sbin/chpasswd
+ Defaults:apache !requiretty
+ <<END
+
+ Note: on different systems the username (here 'apache') may be different, e.g. www.
+ Note: on some systems the disabling tty line may not be needed.

plugins/password/config.inc.php.dist

@@ -295,7 +295,7 @@ $config['password_ximss_port'] = 11024;
 
 // chpasswd Driver options
 // ---------------------
-// Command to use
+// Command to use (see "Sudo setup" in README)
 $config['password_chpasswd_cmd'] = 'sudo /usr/sbin/chpasswd 2> /dev/null';
 
 
@@ -337,9 +337,8 @@ $config['password_virtualmin_format'] = 0;
 
 // pw_usermod Driver options
 // --------------------------
-// Use comma delimited exlist to disable password change for users
+// Use comma delimited exlist to disable password change for users.
-// Add the following line to visudo to tighten security:
+// See "Sudo setup" in README file.
-// www  ALL=NOPASSWORD: /usr/sbin/pw
 $config['password_pw_usermod_cmd'] = 'sudo /usr/sbin/pw usermod -h 0 -n';