Shadow file entry question

[me-5yx05kfkO/aqeI1yJSURBw at public.gmane.org (Matthew Gillen)]

On 11/19/2010 11:18 AM, Chandler, Scott wrote:
> The "x" is a standin for an encrypted password in the *passwd* file, not the shadow file.
> 
> If I had to guess, I'd say that someone manually edited the shadow file to prevent logons but I can't confirm that.
> 
> Any other thoughts?

man 5 shadow:
>       encrypted password
>            Refer to crypt(3) for details on how this string is interpreted.
> 
>            If the password field contains some string that is not a valid result of crypt(3), for instance ! or *, the user will not be able to use a
>            unix password to log in (but the user may log in the system by other means).
> 
>            This field may be empty, in which case no passwords are required to authenticate as the specified login name. However, some applications
>            which read the /etc/shadow file may decide not to permit any access at all if the password field is empty.
> 
>            A password field which starts with a exclamation mark means that the password is locked. The remaining characters on the line represent
>            the password field before the password was locked.

'x' is not a valid result of crypt(3).  So it is equivalent to "*" or "!".