Re: [OFFTOPIC] Re: [PATCH] Single user linux

From: Alan Cox (alan@lxorguk.ukuu.org.uk)
Date: Tue Apr 24 2001 - 12:16:54 EST


> And get_mail must have elevated privileges to search for the users mail...
> or sendmail must have already switched user on reciept to put it in the
> users inbox which also requires privleges...

No. Think instead of blindly following existing implementation

        socket(AF_UNIX, SOCK_STREAM, 0);
        connect("/var/run/mailservice");
        write("GIMMEMYMAIL\n");
        read("200 CATCH..");
        read(all my mail)

The daemon needs no priviledge. The client needs no priviledge. The
PEERCRED authentication on AF_UNIX sockets does the work. I can even pass you
back the file handle of the mailbox if I was using an old style non database
indexed mail spool.

> It's much more efficent to process each mail as it arrives.

You are doing a lot more exec() calls that way. If you get enough mail
to make spool space an issue you want a daemon.

Alan

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This archive was generated by hypermail 2b29 : Mon Apr 30 2001 - 21:00:12 EST