Chentao Credungtao
2021-Jan-24 10:30 UTC
[Samba] Is “obey pam restrictions” still supposed to work in Samba 4?
Hi, The up-to-date Samba doc says (https://www.samba.org/samba/docs/current/man-html/smb.conf.5.html) : "When Samba 3.0 is configured to enable PAM support (i.e. --with-pam), this parameter will control whether or not Samba should obey PAM's account and session management directives." Is this still supposed to work with Samba 4 ? I had some strange result, it seems PAM's restrictions are enforced once, but then not anymore. I tried to set up a file-size limitation on a Samba share. I'm not talking about quotas, I'm talking about preventing users from storing files that are bigger than 100MB, for example. I used /etc/security/limits.conf for this. It almost works. Well, it works the first time a user tries to create a file, and then not anymore. Here's what I did : ??? - First I defined a hard filesize limit of 100MB for user johndoe in /etc/security/limits.conf :??? "johndoe??? hard fsize??? 102400" ??? - Then I added "session required pam_limits.so" to /etc/pam.d/samba, in order to tell PAM to enforce the limitations : ??? - And finally, I added "obey pam restrictions = yes" to /etc/samba/smb.conf At first it seemed promising, when user johndoe tries to copy a file > 100MB, a Windows 10 client throws the following error : An unexpected error is keeping you from copying the file...An unexpected network error occured So far, so good ! That's what I wanted, prevent the user to store a file > 100MB But if I click on "Try again", the file is copied anyway. And if I then try to copy more files > 100MB, no more error message is thrown, and the copies proceed. If user johndoe logs out and back in, same result : the first attempt throws an error, the following attempts succeed. So, it seems the restriction I set in /etc/security/limits.conf is only enforced at the first attempt, and is no more enforced afterwards. Any idea why ? Or any idea how I could achieve my goal (prevent a user to copy a file > 100MB) ?