linux-kernel - Re: [PATCH 1/5] vsprintf/Documentation: Add X to %*ph extension to output upper case hex

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:   Fri, 27 Aug 2021 10:48:33 +0300
From:   Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
To:     Joe Perches <joe@...ches.com>
Cc:     Petr Mladek <pmladek@...e.com>,
        Steven Rostedt <rostedt@...dmis.org>,
        Sergey Senozhatsky <senozhatsky@...omium.org>,
        Rasmus Villemoes <linux@...musvillemoes.dk>,
        Jonathan Corbet <corbet@....net>, linux-doc@...r.kernel.org,
        linux-kernel@...r.kernel.org
Subject: Re: [PATCH 1/5] vsprintf/Documentation: Add X to %*ph extension to
 output upper case hex

On Thu, Aug 26, 2021 at 11:43:01AM -0700, Joe Perches wrote:
> A few sysfs output uses of hex arrays are uppercase and are nominally ABI.
> 
> Add a mechanism to the existing vsprintf %*ph hex output extension to
> support upper case hex output.

...

> +	The preferred output is lowercase
>  	%*ph	00 01 02  ...  3f
>  	%*phC	00:01:02: ... :3f
>  	%*phD	00-01-02- ... -3f
>  	%*phN	000102 ... 3f
> +	Formats with X are uppercase, used for backwards compatibility
> +	%*phX	00 01 02  ...  3F
> +	%*phCX	00:01:02: ... :3F
> +	%*phDX	00-01-02- ... -3F
> +	%*phNX	000102 ... 3F

Why not using %*pH...?

...

> +	char locase = 0x20;	/* ASCII OR'd for lower case see: number() */

If you use h vs H, you may derive this from (fmt[...] & SMALL).

-- 
With Best Regards,
Andy Shevchenko