linux-kernel - Re: [PATCH 2/3] random: rng-seed source is utf-8

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]

Message-ID: <f15511bf-b840-0633-3354-506b7b0607fe@android.com>
Date:   Fri, 14 Feb 2020 14:55:36 -0800
From:   Mark Salyzyn <salyzyn@...roid.com>
To:     "Theodore Y. Ts'o" <tytso@....edu>, Rob Herring <robh@...nel.org>
Cc:     Masami Hiramatsu <mhiramat@...nel.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        Android Kernel Team <kernel-team@...roid.com>,
        Arnd Bergmann <arnd@...db.de>,
        Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        Richard Henderson <richard.henderson@...aro.org>,
        Mark Brown <broonie@...nel.org>,
        Kees Cook <keescook@...omium.org>,
        Hsin-Yi Wang <hsinyi@...omium.org>,
        Vasily Gorbik <gor@...ux.ibm.com>,
        Andrew Morton <akpm@...ux-foundation.org>,
        Steven Rostedt <rostedt@...dmis.org>,
        Mike Rapoport <rppt@...ux.ibm.com>,
        Arvind Sankar <nivedita@...m.mit.edu>,
        Dominik Brodowski <linux@...inikbrodowski.net>,
        Thomas Gleixner <tglx@...utronix.de>,
        Alexander Potapenko <glider@...gle.com>,
        Jonathan Corbet <corbet@....net>,
        Mauro Carvalho Chehab <mchehab+samsung@...nel.org>,
        Josh Poimboeuf <jpoimboe@...hat.com>,
        Pawan Gupta <pawan.kumar.gupta@...ux.intel.com>,
        Juergen Gross <jgross@...e.com>,
        Linux Doc Mailing List <linux-doc@...r.kernel.org>
Subject: Re: [PATCH 2/3] random: rng-seed source is utf-8

On 2/14/20 2:47 PM, Theodore Y. Ts'o wrote:
> On Fri, Feb 14, 2020 at 01:58:35PM -0600, Rob Herring wrote:
>> On Fri, Feb 14, 2020 at 12:10 AM Masami Hiramatsu <mhiramat@...nel.org> wrote:
>>> From: Mark Salyzyn <salyzyn@...roid.com>
>>>
>>> commit 428826f5358c922dc378830a1717b682c0823160
>>> ("fdt: add support for rng-seed") makes the assumption that the data
>>> in rng-seed is binary, when it is typically constructed of utf-8
>> Typically? Why is that?
>>
>>> characters which has a bitness of roughly 6 to give appropriate
>>> credit due for the entropy.
> This is why I really think what gets specified via the boot command
> line, or bootconfig, should specify the bits of entropy and the
> entropy seed *separately*, so it can be specified explicitly, instead
> of assuming that *everyone knows* that rng-seed is either (a) a binary
> string, or (b) utf-8, or (c) a hex string.  The fact is, everyone does
> *not* know, or everyone will have a different implementation, which
> everyone will say is *obviously* the only way to go....
>
> 	      	     		     	  - Ted

Given that the valid option are between 4 (hex), 6 (utf-8) or 8 
(binary), we can either split the difference and accept 6; or take a 
pass at the values and determine which of the set they belong to 
[0-9a-fA-F], [!-~] or [\000-\377]  nor need to separately specify.

-- Mark