Re: [PATCH v5 02/27] mbedtls: add mbedtls into the build system

On Wed, 14 Aug 2024 at 16:22, Raymond Mao raymond.mao@linaro.org wrote:

Hi Ilias,

On Wed, 14 Aug 2024 at 08:08, Ilias Apalodimas ilias.apalodimas@linaro.org wrote:

...

Hi Raymond,

On Wed, 31 Jul 2024 at 20:27, Raymond Mao raymond.mao@linaro.org wrote:

...

Port mbedtls with adapted libc header files. Add mbedtls default config header file. Optimize mbedtls default config by disabling unused features to reduce the target size. Add mbedtls kbuild makefile. Add Kconfig skeleton and config submenu entry for selecting crypto libraries between mbedtls and legacy ones. Add the mbedtls include directories into the build system.

Subsequent patches will separate those Kconfigs into pairs of _LEGACY and _MBEDTLS for controlling the implementations of legacy crypto libraries and MbedTLS ones respectively.

The motivation of moving and adapting *INT* macros from kernel.h to limits.h is to fullfill the MbedTLS building requirement. The conditional compilation statements in MbedTLS expects the *INT* macros as constant expressions, thus expressions like `((int)(~0U >> 1))` will not work.

Prerequisite

This patch series requires mbedtls git repo to be added as a subtree to the main U-Boot repo via:

$ git subtree add --prefix lib/mbedtls/external/mbedtls \ https://github.com/Mbed-TLS/mbedtls.git \ v3.6.0 --squash

Moreover, due to the Windows-style files from mbedtls git repo, we need to convert the CRLF endings to LF and do a commit manually:

$ git add --renormalize . $ git commit

Signed-off-by: Raymond Mao raymond.mao@linaro.org

Changes in v2

• Disabled unused MbedTLS features to optimize the target size.

Changes in v3

• Removed changes in stdio.h.

Changes in v4

• Move limits.h as a common header file that is included by kernel.h.
• Refactor the Kconfig to support legacy and MbedTLS options for each algorithm.
• Refactor MbedTLS makefile and default config file to remove unused config options and objects.

Changes in v5

• Merged patch #9 of v4 into this patch.
• Removed unused config MBEDTLS_LIB_TLS.
• Refactored MbedTLS Makefile and default config file.

Makefile | 6 +++ include/limits.h | 29 ++++++++++++++ include/linux/kernel.h | 13 +----- include/stdlib.h | 1 + lib/Kconfig | 4 ++ lib/Makefile | 2 + lib/mbedtls/Kconfig | 47 ++++++++++++++++++++++ lib/mbedtls/Makefile | 41 +++++++++++++++++++ lib/mbedtls/mbedtls_def_config.h | 69 ++++++++++++++++++++++++++++++++ lib/mbedtls/port/assert.h | 12 ++++++ 10 files changed, 212 insertions(+), 12 deletions(-) create mode 100644 include/limits.h create mode 100644 lib/mbedtls/Kconfig create mode 100644 lib/mbedtls/Makefile create mode 100644 lib/mbedtls/mbedtls_def_config.h create mode 100644 lib/mbedtls/port/assert.h

diff --git a/Makefile b/Makefile index 07d7947c8af..fd855dbd5c9 100644 --- a/Makefile +++ b/Makefile @@ -829,6 +829,12 @@ KBUILD_HOSTCFLAGS += $(if $(CONFIG_TOOLS_DEBUG),-g) UBOOTINCLUDE := \ -Iinclude \ $(if $(KBUILD_SRC), -I$(srctree)/include) \

•   $(if $(CONFIG_MBEDTLS_LIB), \
  

•           "-DMBEDTLS_CONFIG_FILE=\"mbedtls_def_config.h\"" \
  

•           -I$(srctree)/lib/mbedtls \
  

•           -I$(srctree)/lib/mbedtls/port \
  

•           -I$(srctree)/lib/mbedtls/external/mbedtls \
  

•           -I$(srctree)/lib/mbedtls/external/mbedtls/include) \
    $(if $(CONFIG_$(SPL_)SYS_THUMB_BUILD), \
            $(if $(CONFIG_HAS_THUMB2), \
                    $(if $(CONFIG_CPU_V7M), \
  

diff --git a/include/limits.h b/include/limits.h new file mode 100644 index 00000000000..cc691d15650 --- /dev/null +++ b/include/limits.h @@ -0,0 +1,29 @@ +/* SPDX-License-Identifier: GPL-2.0+ */ +/*

• • Copyright (c) 2023 Linaro Limited
• • Author: Raymond Mao raymond.mao@linaro.org
• */

+#ifndef _LIMITS_H +#define _LIMITS_H

+#define INT_MAX 0x7fffffff +#define UINT_MAX 0xffffffffUL +#define CHAR_BIT 8 +#define UINT32_MAX 0xffffffffUL +#define UINT64_MAX 0xffffffffffffffffUL

Some of these seem wrong e.g UINT64_MAX should be ULL, etc Can you keep the original definitions?

The original definitions cannot work with building MbedTLS. As I stated in the commit message:

The conditional compilation statements in MbedTLS expects the
*INT* macros as constant expressions, thus expressions like
`((int)(~0U >> 1))` will not work.

Ah that's ok, fix the UL etc and keep it as is

[snip]

Raymond