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Date:      Thu, 03 Oct 2002 12:15:52 -0700
From:      "Firsto Lasto" <firstolasto@hotmail.com>
To:        mark@grondar.za
Cc:        freebsd-hackers@FreeBSD.ORG
Subject:   Re: PRNG not seeded - error in non-root ssh inside 4.6.2 jails...
Message-ID:  <F88c55PUrob2JaBPZYo0000662f@hotmail.com>

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Ok, here you are - as a normal user (non root) inside the jail, I have run:

$ dd if=/dev/random of=/dev/stdout bs=512 count=1 | hexdump -C
dd: /dev/stdout: Permission denied

$ ls -asl /dev/stdout
0 crw-------  1 root  wheel   22,   1 Sep  3 21:46 /dev/stdout

All of this was _after_ I ran the `chmod a+r /dev/*rand*` command.

So then, as root I ran: `chmod 0666 /dev/stdout` and then I ran your `dd` 
command and got:

$ dd if=/dev/random of=/dev/stdout bs=512 count=1 | hexdump -C
0+0 records in
0+0 records out
0 bytes transferred in 0.000036 secs (0 bytes/sec)

I hope this is useful, and thank you for your help.




>
> > I have found that if you create a jail in FreeBSD 4.6.2, and then log 
>into
> > that jail ... if you are root you can scp and ssh just fine.  However if 
>you
> > are not root and you attempt to ssh or scp, you get this error:
> >
> > PRNG is not seeded
>
>Hmmm.
>
> > A few details - first, I created my jail by simply using the dump 
>command to
> > dump my / filesystem, and then restoring that inside the jail.  Not 
>elegant,
> > but it works - so the jail in question has a full /dev and everything.
> >
> > Second, I used the exact same method in 4.6.1 and did not have problems.
> >
> > I saw a usenet post that recommended solving the problem with this:
> >
> > "chmod a+r /dev/*rand*"
>
>You seem to be on the right track in assuming it is a /dev/[u]random
>problem.
>
>Can you confirm this by (as a pleb user) dumping some random output?
>
>$ dd if=/dev/random of=/dev/stdout bs=512 count=1 | hexdump -C
>
>(and same for /dev/urandom).
>
>Please also give a ls -l /dev/*random.
>
> > however I tried that, and now when I try to ssh or scp from a non root 
>user
> > inside the jail, I get:
> >
> > "Host key verification failed"
> >
> > Does anyone know why this happens, why it didn't happen prior to 4.6.2, 
>and
> > how I can fix it ?
>
>The random device has not changed, but the OpenSSL code has. Maybe 
>OpenSSL's
>internal PRNG is doing something naughty.
>
>M
>--
>o       Mark Murray
>\_
>O.\_    Warning: this .sig is umop ap!sdn




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