[PATCH v7 02/10] lib: uuid: introduce uuid_str_to_le_bin function

[Abdellatif El Khlifi]

On Fri, Nov 11, 2022 at 05:02:26PM +0000, Anders Dellien wrote:
> Hi Abdel,
> 
> From: U-Boot <u-boot-bounces at lists.denx.de> on behalf of Abdellatif El Khlifi <abdellatif.elkhlifi at arm.com>
> Date: Monday, 7 November 2022 at 19:22
> To: Abdellatif El Khlifi <Abdellatif.ElKhlifi at arm.com>
> Cc: Drew Reed <Drew.Reed at arm.com>, Achin Gupta <Achin.Gupta at arm.com>, ilias.apalodimas at linaro.org <ilias.apalodimas at linaro.org>, jens.wiklander at linaro.org <jens.wiklander at linaro.org>, nd <nd at arm.com>, sjg at chromium.org <sjg at chromium.org>, trini at konsulko.com <trini at konsulko.com>, u-boot at lists.denx.de <u-boot at lists.denx.de>, Vishnu Banavath <Vishnu.Banavath at arm.com>, Xueliang Zhong <Xueliang.Zhong at arm.com>
> Subject: [PATCH v7 02/10] lib: uuid: introduce uuid_str_to_le_bin function
> convert UUID string to little endian binary data
> 
> Signed-off-by: Abdellatif El Khlifi <abdellatif.elkhlifi at arm.com>
> Cc: Tom Rini <trini at konsulko.com>
> Cc: Simon Glass <sjg at chromium.org>
> Cc: Ilias Apalodimas <ilias.apalodimas at linaro.org>
> Cc: Jens Wiklander <jens.wiklander at linaro.org>
> 
> ---
> 
> Changelog:
> ===============
> 
> v7:
> 
> * rename be_uuid_str_to_le_bin() to uuid_str_to_le_bin()
> * make uuid_str_to_le_bin() implementation similar to uuid_str_to_bin()
>   by using same APIs
> 
> v4:
> 
> * rename ffa_uuid_str_to_bin to be_uuid_str_to_le_bin and put in
>   a standalone commit (the current)
> 
> v3:
> 
> * introduce ffa_uuid_str_to_bin (provided by
>   arm_ffa: introduce Arm FF-A low-level driver)
> 
> include/uuid.h |  8 ++++++++
>  lib/uuid.c     | 46 ++++++++++++++++++++++++++++++++++++++++++++++
>  2 files changed, 54 insertions(+)
> 
> diff --git a/include/uuid.h b/include/uuid.h
> index 4a4883d3b5..293a8eb0a5 100644
> --- a/include/uuid.h
> +++ b/include/uuid.h
> @@ -2,6 +2,8 @@
>  /*
>   * Copyright (C) 2014 Samsung Electronics
>   * Przemyslaw Marczak <p.marczak at samsung.com>
> + * (C) Copyright 2022 ARM Limited
> + * Abdellatif El Khlifi <abdellatif.elkhlifi at arm.com>
>   */
>  #ifndef __UUID_H__
>  #define __UUID_H__
> @@ -44,4 +46,10 @@ int uuid_guid_get_bin(const char *guid_str, unsigned char *guid_bin);
>  const char *uuid_guid_get_str(const unsigned char *guid_bin);
>  void gen_rand_uuid(unsigned char *uuid_bin);
>  void gen_rand_uuid_str(char *uuid_str, int str_format);
> +
> +/**
> + * uuid_str_to_le_bin - Converts a UUID string to little endian binary data
> + */
> +int uuid_str_to_le_bin(const char *uuid_str, unsigned char *uuid_bin);
> +
>  #endif
> diff --git a/lib/uuid.c b/lib/uuid.c
> index 465e1ac38f..cde5ae2bb7 100644
> --- a/lib/uuid.c
> +++ b/lib/uuid.c
> @@ -1,6 +1,8 @@
>  // SPDX-License-Identifier: GPL-2.0+
>  /*
>   * Copyright 2011 Calxeda, Inc.
> + * (C) Copyright 2022 ARM Limited
> + * Abdellatif El Khlifi <abdellatif.elkhlifi at arm.com>
>   */
> 
>  #include <common.h>
> @@ -346,6 +348,50 @@ int uuid_str_to_bin(const char *uuid_str, unsigned char *uuid_bin,
>          return 0;
>  }
> 
> +/**
> + * uuid_str_to_le_bin() - Convert string UUID to little endian binary data.
> + * @uuid_str:  pointer to UUID string
> + * @uuid_bin:  pointer to allocated array for little endian output [16B]
> + *
> + * UUID string is 36 characters (36 bytes):
> + *
> + * xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
> + *
> + * where x is a hexadecimal character. Fields are separated by '-'s.
> + * When converting to a little endian binary UUID, the string fields are reversed.
> + *
> + * Return:
> + *
> + *    uuid_bin filled with little endian UUID data
> + *    On success 0 is returned. Otherwise, failure code.
> + */
> +int uuid_str_to_le_bin(const char *uuid_str, unsigned char *uuid_bin)
> +{
> +       u16 tmp16;
> +       u32 tmp32;
> +       u64 tmp64;
> +
> +       if (!uuid_str_valid(uuid_str) || !uuid_bin)
> +               return -EINVAL;
> +
> +       tmp32 = cpu_to_le32(hextoul(uuid_str, NULL));
> +       memcpy(uuid_bin, &tmp32, 4);
> +
> +       tmp16 = cpu_to_le16(hextoul(uuid_str + 9, NULL));
> +       memcpy(uuid_bin + 4, &tmp16, 2);
> +
> +       tmp16 = cpu_to_le16(hextoul(uuid_str + 14, NULL));
> +       memcpy(uuid_bin + 6, &tmp16, 2);
> +
> +       tmp16 = cpu_to_le16(hextoul(uuid_str + 19, NULL));
> +       memcpy(uuid_bin + 8, &tmp16, 2);
> +
> +       tmp64 = cpu_to_le64(hextoul(uuid_str + 24, NULL));
> +       memcpy(uuid_bin + 10, (char *)&tmp64, 6);
> 
> I think we might risk overflow here on platforms where “ulong” happens to be 32 bits.

Thanks Anders, a very valid point.

I will use simple_strtoull() in place of hextoul()

I'll make the change in v8.

> 
> +
> +       return 0;
> +}
> +
>  /*
>   * uuid_bin_to_str() - convert big endian binary data to string UUID or GUID.
>   *
> --
> 2.17.1