[TUHS] success, bj assembled and linked in Unix v5

[TUHS] success, bj assembled and linked in Unix v5

[Norman Wilson]

Mark Longridge:

  chmod 0744 bj

Dave Horsfall:

  That has to be the world's oddest "chmod" command.

======

Not by a long shot.

Recently, for reasons related both to NFS permissions and to
hardware testing, I have occasionally been making directories
with mode 753.

At the place I worked 20 years ago, we wanted a directory
into which anonymous ftp could write, so that people could
send us files; but we didn't want it to become a place for
creeps to stash their creepy files.  I thought about the
problem briefly, then made the directory with mode 0270,
owned by the user used for anonymous ftp and by a group
containing all the staff members allowed to receive files
that way.  That way creeps could deposit files but couldn't
see what was there.

I also told cron to run every ten minutes, changing the
permissions of any file in that directory to 0060.

Oh, and I had already maniacally (and paranoiacally)
excised from ftpd the code allowing ftp to change permissions.

I admit I can't think of a reason to use 744 offhand, since
if you can read the file you can copy it and make the copy
executable.  But UNIX permissions can be used in so many
interesting ways that I'm not willing to claim there is no
such reason just because I can't see what it is.

Norman Wilson
Toronto ON

[TUHS] success, bj assembled and linked in Unix v5

[John Cowan]

Norman Wilson scripsit:

> Oh, and I had already maniacally (and paranoiacally)
> excised from ftpd the code allowing ftp to change permissions.

I needed an FTP server some time back to support only *non*-anonymous
logins, where the logins had nothing to do with the underlying system.
I came up with this:

<http://ccil.org/~cowan/publish-ftpd>

I was going to add HTTP support with basic auth, but never got around
to it.

> I admit I can't think of a reason to use 744 offhand, since
> if you can read the file you can copy it and make the copy
> executable.  

But it won't be owned by the original owner, which means any setuid bit
will give it the permissions of the copy-maker.

-- 
John Cowan          http://www.ccil.org/~cowan        cowan at ccil.org
Awk!" sed Grep. "A fscking python is perloining my Ruby; let me bash
    him with a Cshell!  Vi didn't I mount it on a troff?" --Francis Turner

[TUHS] success, bj assembled and linked in Unix v5

[random832]

On Sat, Jun 13, 2015, at 21:41, John Cowan wrote:
> But it won't be owned by the original owner, which means any setuid bit
> will give it the permissions of the copy-maker.

Right, but 744 doesn't include a setuid bit.

[TUHS] success, bj assembled and linked in Unix v5

[Dave Horsfall]

On Fri, 12 Jun 2015, Mark Longridge wrote:

> chmod 0744 bj

That has to be the world's oddest "chmod" command.

-- 
Dave Horsfall DTM (VK2KFU)   "Those who don't understand security will suffer."
http://www.horsfall.org/spam.html (and check the home page whilst you're there)

[TUHS] success, bj assembled and linked in Unix v5

[Mark Longridge]

> 744?   You want the group and others to be able to read but not execute?

You are right, chmod 0755 would have made more sense.

On 6/12/15, Ronald Natalie <ron at ronnatalie.com> wrote:
> 744?   You want the group and others to be able to read but not execute?
>
>> On Jun 12, 2015, at 4:33 PM, Mark Longridge <cubexyz at gmail.com> wrote:
>>
>> OK, success...
>>
>> in Unix v5:
>>
>> as bj.s etc.s us.s
>> ld a.out -lc
>> mv a.out bj
>> chmod 0744 bj
>>
>> It seems to work OK now. Probably should work on v6 and v7 as well.
>>
>> Mark
>> _______________________________________________
>> TUHS mailing list
>> TUHS at minnie.tuhs.org
>> https://minnie.tuhs.org/mailman/listinfo/tuhs
>
>

[TUHS] success, bj assembled and linked in Unix v5

[Ronald Natalie]

744?   You want the group and others to be able to read but not execute?

> On Jun 12, 2015, at 4:33 PM, Mark Longridge <cubexyz at gmail.com> wrote:
> 
> OK, success...
> 
> in Unix v5:
> 
> as bj.s etc.s us.s
> ld a.out -lc
> mv a.out bj
> chmod 0744 bj
> 
> It seems to work OK now. Probably should work on v6 and v7 as well.
> 
> Mark
> _______________________________________________
> TUHS mailing list
> TUHS at minnie.tuhs.org
> https://minnie.tuhs.org/mailman/listinfo/tuhs

[TUHS] success, bj assembled and linked in Unix v5

[cowan]

Mark Longridge scripsit:

> OK, success...
>
> in Unix v5:

Excellent!  Why not post a transcript of a game?

-- 
John Cowan          http://www.ccil.org/~cowan        cowan at ccil.org
Pour moi, les villes du Silmarillion ont plus de realite que Babylone.
                --Christopher Tolkien, as interviewed by Le Monde

[TUHS] success, bj assembled and linked in Unix v5

[Noel Chiappa]

    > From: Mark Longridge <cubexyz at gmail.com>

    > OK, success...

Yeah, I just got there too, but by a slightly longer route!

(Google wasn't turning up the matches for the routines I needed, which you
found in etc.s, etc - it seems the source archive on Minnie isn't being
indexed by Google. So I wound up cobbling them together with a mix of stuff
from other places, along with stuff I wrote/modified.)

    > Probably should work on v6 and v7 as well.

Does on V6, dunno about V7.

    > It seems to work OK now.

Yes, but this is _not_ the source for the V5/V6 'bj'. (I just checked,
and the V5 and V6 binaries are identical.)

Right at the moment, I've used enough time on this - I may get back to
it later, and disassemble the V5/V6 binary and see what the original
source looks like.

	Noel

[TUHS] success, bj assembled and linked in Unix v5

[Mark Longridge]

OK, success...

in Unix v5:

as bj.s etc.s us.s
ld a.out -lc
mv a.out bj
chmod 0744 bj

It seems to work OK now. Probably should work on v6 and v7 as well.

Mark