From owner-freebsd-arch Mon Oct 14 10:28:42 2002 Delivered-To: freebsd-arch@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 993BE37B401; Mon, 14 Oct 2002 10:28:40 -0700 (PDT) Received: from fledge.watson.org (fledge.watson.org [204.156.12.50]) by mx1.FreeBSD.org (Postfix) with ESMTP id 7307843EA9; Mon, 14 Oct 2002 10:28:39 -0700 (PDT) (envelope-from robert@fledge.watson.org) Received: from fledge.watson.org (fledge.pr.watson.org [192.0.2.3]) by fledge.watson.org (8.12.4/8.12.4) with SMTP id g9EHRwOo062016; Mon, 14 Oct 2002 13:27:58 -0400 (EDT) (envelope-from robert@fledge.watson.org) Date: Mon, 14 Oct 2002 13:27:57 -0400 (EDT) From: Robert Watson X-Sender: robert@fledge.watson.org To: "Vladimir B. Grebenschikov,Moscow,408-7227,123-4567,Some-info" Cc: freebsd-arch@freebsd.org, freebsd-current@freebsd.org Subject: Re: short uid/gid In-Reply-To: Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-arch@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG Yeah, this is a Known Problem, and it's quite unfortunate, actually. I looked at trying to solve it -- changing the types respectively to uid_t, gid_t, and mode_t, but it involved a lot of ABI munging because the structures are shared between the userland interface and the kernel implementation. The result is that any change in the kernel structure really requires you to break out the user structures from the kernel structure, which requires a lot of work. Also, ipc_perm is shared between all three SysVIPC services, and to compound things, there are already ofoo() interfaces for older versions of the structures. My belief is that seperating the user and kernel structures is really necessary -- making a kipc_perm, etc, so we can better support fine-grained locking and extensible security. However, someone has to do the grunt work, and last time I tried, I spent several days and only made a bit of progress. If you want to give a first pass at breaking out the user and kernel structures and send a patch, I'll be happy to work with you to get it integrated. I think the steps are: (1) Divorce user and kernel structures for all of the SysVIPC interfaces, and provide functions to map between them as necessary. (2) Remove the original compatibility interfaces left over from eons ago (and figure out how many eons ago so we know what ABIs we're finally removing). (3) Define new userland versions of necessary structures and create a new set of ofoo() and foo() interfaces based on the change. (4) Go back through and dribble the kernel structures with new toys, such as 'struct label', etc. Robert N M Watson FreeBSD Core Team, TrustedBSD Projects robert@fledge.watson.org Network Associates Laboratories On Mon, 14 Oct 2002, Vladimir B. Grebenschikov,Moscow,408-7227,123-4567,Some-info wrote: > > Hi > > I have found that SysVIPC functions uses structure with short uid/gid types. > > What is valid solution ? > > Change types to uid_t/gid_t (but this will broke binary compatibility) > Change syscalls to old_* and add new with "right" structures, > or something else ? > > struct ipc_perm { > ushort cuid; /* creator user id */ > ushort cgid; /* creator group id */ > ushort uid; /* user id */ > ushort gid; /* group id */ > ushort mode; /* r/w permission */ > ushort seq; /* sequence # (to generate unique msg/sem/shm id) */ > key_t key; /* user specified msg/sem/shm key */ > }; > > -- > Vladimir B. Grebenschikov > vova@sw.ru, SWsoft, Inc. > > To Unsubscribe: send mail to majordomo@FreeBSD.org > with "unsubscribe freebsd-arch" in the body of the message > To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-arch" in the body of the message