lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date:	Mon, 18 May 2009 01:01:58 +0900
From:	KOSAKI Motohiro <kosaki.motohiro@...fujitsu.com>
To:	Jon Grant <jg@...k.org>
Cc:	linux-kernel@...r.kernel.org
Subject: Re: dd if=/dev/random of=data.bin bs=512 count=1

> Hello
>
> Issuing this command, I expected to get a file 4096 bytes in size.
> Could someone let me know if I have missed something..? Or is there a
> problem with using /dev/random this way?
>
> if I have a count=10 it hangs forever (several hours).
>
> Changing to use /dev/urandom and it generates the file ok.

you already have the answer. /dev/random might blocked, /dev/urandom doesn't.


> Please include my email address in replies,  as I'm not a member of this list.
>
> Best regards, Jon
>
> $ dd if=/dev/random of=data.bin bs=512 count=1
> 0+1 records in
> 0+1 records out
> 8 bytes (8 B) copied, 4.47366 s, 0.0 kB/s
>
> $ dd --version
> dd (coreutils) 6.10
>
> $ uname -a
> Linux ubuntu 2.6.28-11-generic #42-Ubuntu SMP Fri Apr 17 01:57:59 UTC
> 2009 i686 GNU/Linux
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@...r.kernel.org
> More majordomo info at  http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at  http://www.tux.org/lkml/
>
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Powered by blists - more mailing lists

Powered by Openwall GNU/*/Linux Powered by OpenVZ