From cse.psu.edu!9fans-outgoing-owner Thu May  9 18:32:08 1996
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To:	9fans@cse.psu.edu (Plan 9 from Bell Labs fans)
Subject: Small patch for kfs to show free space on disk
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Date:	Thu, 9 May 1996 18:22:44 -0400
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From:	Nickolay Saukh <nms@nns.ru>
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Status: RO

Here is small patch for /sys/src/cmd/disk/kfs/con.c which allows
to get the following numbers from kfs

	number of free blocks
	file system size in blocks
	block size

Don't forget rebuild kernel (9pcdisk for PCs).

---------- cut here to destroy your CRT ----------
417a
	"free",	cmd_free, "",
.
408a
void
cmd_free(void)
{
	Iobuf *p;
	Superb *s;

	p = getbuf(cur_fs->dev, superaddr(cur_fs->dev), Bread);
	s = (Superb*) p->iobuf;
	cprint("%ld %ld %d\n", s->tfree, s->fsize, RBUFSIZE);
	putbuf(p);
}

.
---------- cut here to destroy your CRT ----------





From: miller@hamnavoe.demon.co.uk
To: 9fans@cse.psu.edu
Date: Sat, 2 May 1998 10:48:14 BST
Subject: Re: [9fans] more secure kfs
Sender: owner-9fans@cse.psu.edu
Reply-To: 9fans@cse.psu.edu

Kenji Arisawa <arisawa@aichi-u.ac.jp> asks:

> Does anyone has a patch to kfs that enables more secure kfs?
> 
> I would like to prohibit some kfs commands by the user who is
> not the owner of /dev/hd0*

It's simple to prohibit *all* kfs commands except from hostowner,
by changing main.c as shown below.  A filter program could then
be started from cpurc to accept commands on another /srv file
and pass the safe ones (sync?) to /srv.kfs [left as an exercise
for the reader].

==========================================
diff /sys/src/cmd/disk/kfs/main.c main.c
11c11
< int	srvfd(char*, int);
---
> int     srvfd(char*, int, int);
296c296
< 	srvfd(buf, p[0]);
---
> 	srvfd(buf, p[0], 0600);
398c398
< 	srvfd(buf, sfd);
---
> 	srvfd(buf, sfd, 0666);
412c412
< srvfd(char *s, int sfd)
---
> srvfd(char *s, int sfd, int perm)
417c417
< 	fd = create(s, OWRITE, 0666);
---
> 	fd = create(s, OWRITE, perm);
420c420
< 		fd = create(s, OWRITE, 0666);
---
> 		fd = create(s, OWRITE, perm);
==========================================

-- Richard Miller