[PATCH v3 0/3] hvmloader: add new SMBIOS tables (7,8,9,26,27,28)

["Petr Beneš" <w1benny@gmail.com>]

From: Petr Beneš <w1benny@gmail.com>

Changes since v2:
- Added sizeof_field and offsetofend macros to common-macros.h.
- Used offsetofend macro everywhere to make semantically sense.
- Added BUILD_BUG_ON to ensure offsets are correct based on the SMBIOS
  specification (with explanation in the comments).
- Fixed commit message of the second patch to mention the new smbios_pt_copy
  function.
- Fixed nits (empty lines, misplaced *).
- Retained the original comment "Only present when passed in" + added it to
  the new tables where applicable.
- Replaced hardcoded offset for chassis_handle in smbios_type_2_init.

Changes since v1:
- Swapped the order of S-o-b in the last commit message.

Resubmitting patch from Anton Belousov and addressing review comments
from Jan: https://old-list-archives.xen.org/archives/html/xen-devel/2022-01/msg00725.html

Original message:
> SMBIOS tables like 7,8,9,26,27,28 are neccessary to prevent sandbox detection
> by malware using WMI-queries. New tables can be mapped to memory from binary
> file specified in "smbios_firmware" parameter of domain configuration.
> If particular table is absent in binary file, then it will not be mapped to
> memory. This method works for Windows domains as tables 7,8,9,26,27,28 are not
> critical for OS boot and runtime. Also if "smbios_firmware" parameter is not
> provided, these tables will be skipped in write_smbios_tables function.

Further explanation:
Some malware samples are known to check presence of various hardware components
(like CPU fan, CPU temperature sensor, etc.) by WMI queries. If these components
are not present, then malware can assume that it is running in a sandbox and
will not execute its payload.

This patch will allow security researchers to create a custom SMBIOS
firmware binary file that contains these tables.

Petr Beneš (3):
  tools: add sizeof_field and offsetofend macros
  hvmloader: fix SMBIOS table length checks
  hvmloader: add new SMBIOS tables (7, 8, 9, 26, 27, 28)

 tools/firmware/hvmloader/smbios.c       | 290 ++++++++++++++++++------
 tools/firmware/hvmloader/smbios_types.h | 109 +++++++--
 tools/include/xen-tools/common-macros.h |   5 +
 3 files changed, 317 insertions(+), 87 deletions(-)

-- 
2.34.1