From owner-freebsd-security  Fri Jun  7 10:28:13 1996
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To: =?KOI8-R?Q?=E1=CE=C4=D2=C5=CA_=FE=C5=D2=CE=CF=D7?= (aka Andrey A.
    Chernov, Black Mage) <ache@astral.msk.su>
cc: security@freebsd.org
Subject: Re: FreeBSD's /var/mail permissions 
In-reply-to: Your message of "Fri, 07 Jun 1996 20:19:02 +0400."
             <199606071619.UAA00541@astral.msk.su> 
Date: Fri, 07 Jun 1996 10:27:21 -0700
From: Paul Traina <pst@shockwave.com>
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I'm confused, why do you say adduser must create new user mailbox?
Mail.local is already suid root and adduser should deliver a preformatted
mail message with mail.local.

Paul

  From: =?KOI8-R?Q?=E1=CE=C4=D2=C5=CA_=FE=C5=D2=CE=CF=D7?= (aka Andrey A. Chern
>>ov, Black Mage) <ache@astral.msk.su>
  Subject: Re: FreeBSD's /var/mail permissions
  >     If popper were the only problem, I'd consider chosing a
  >     different directory for this temporary file to be created, such
  >     as /var/tmp.  This leads to a new set of problems and I consider
  >     it less secure than maintaining the file in /var/mail as we have
  >     always done.
  
  Not popper only is the problem, I remember that procmail and
  elm use this feature too (but can work without it too).
  It is common technique to create temporary mailbox in /var/mail
  and rename it to actual mailbox. This method avoid complex
  locking during rewriting window.
  
  > Proposed solution:
  >     I'm considering creating group "mail" and going the setgid route,
  >     so that a program which creates files in /var/mail can be simply
  >     setgid mail.
  > 
  >     This is a well understood mail directory protection mechanism
  >     and employs the "principle of least privilege."
  
  adduser program MUST create new user mailbox in this case to avoid
  pre-created mailboxes.
  Now it only send mail wich can be appended to pre-created mailbox. :-(
  
  -- 
  Andrey A. Chernov        : And I rest so composedly,  /Now, in my bed,
  ache@astral.msk.su       : That any beholder  /Might fancy me dead -
  http://dt.demos.su/~ache : Might start at beholding me,  /Thinking me dead.
  RELCOM Team,FreeBSD Team :         E.A.Poe         From "For Annie" 1849