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https://github.com/chipsec/chipsec
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Nicolas Iooss
4f6ed29c84
Several improvements * Drop the detection of EFI through kallsyms. This detection is no longer useful since commit2c0c4c9fd1("Using CONFIG_EFI instead of user defined HAS_EFI (#1036)") replaced `HAS_EFI` with `CONFIG_EFI`. * Use `...-objs-y` and `...-objs-$(CONFIG_...)` logic to choose which `cpu.asm` file is being built. This is something that other modules do in Linux kernel source. * Introduce `quiet_cmd_...` and `cmd_...` definition in order to use the build system of the kernel to compile `cpu.asm` with NASM. This should prevent issues like the one mentioned in2210002bab("Fixed build error on latest Ubuntu") from happening again. Moreover this makes the custom clean command `rm -f ${asm-path}/cpu.o` no longer necessary. * Remove variables which become unused after these changes. Now, all that `Makefile` needs is a kernel directory, specified with `KSRC`. This change has been tested on a test system running Ubuntu 20.10 and on GitHub Actions workers running Ubuntu 16.04, 18.04 and 20.04 on Linux 5.4.0-1040-azure. It has also been compile-tested on many other Linux distributions using a work-in-progress GitHub Actions configuration (https://github.com/fishilico/chipsec/actions/runs/661200380).
Chipsec Linux kernel module
===========================
This module was originally built on/adapted from fmem 1.5.0 and LoLA (Low Level Access) (https://code.google.com/archive/p/lola-linux/)
To install CHIPSEC framework with the kernel module, please see "Linux Installation" section of chipsec-manual.pdf
When installed, CHIPSEC framework automatically loads and unloads kernel module.
However, if you want to manually build/install the kernel module, please follow instructions below.
To build:
make
To load kernel module:
sudo insmod ./chipsec.ko
To remove kernel module:
sudo rmmod chipsec
NOTE:
You may need run apt-get install python-dev for the Python.h header (needed for switching cpu affinity).
If you already have this in a non-standard location (i.e. any other than /usr/include/python-2.7), you can manually edit the path in drivers/linux/Makefile
NOTE:
Building against recent Linux kernels generates the warning
WARNING: could not find [...]/chipsec/drivers/linux/amd64/.cpu.o.cmd for [...]/chipsec/drivers/linux/amd64/cpu.o
The cmd files are generated with the cmd_and_fixdep rule found in scripts/Kbuild.include, which are used (among other
places) in rule_cc_o_c and rule_as_o_S defined in scripts/Makefile.build (both files are in the kernel source tree).
Removing the warning could be done by converting cpu.asm to cpu.S (i.e. nasm to as), or by adding a rule_nasm_o_asm
to the Kbuild project. The latter might require a new rule in our Makefile:
NASM ?= `which nasm`
NASMFLAGS = -f $(elf-size)
%.o : %.asm
$(NASM) $(NASMFLAGS) $< -o $@
but for now it's probably best to just ignore the warning (it's harmless). See
https://www.kernel.org/doc/ols/2003/ols2003-pages-185-200.pdf for an introduction to Kbuild
https://www.kernel.org/doc/Documentation/kbuild/modules.txt
for more detail.
-------------
fmem 1.5.0
This module creates /dev/fmem device,
that can be used for dumping physical memory,
without limits of /dev/mem (1MB/1GB, depending on distribution)
Tested on i386 and x64, feel free to test it on
different architectures. (and send report please)
Cloned from linux/drivers/char/mem.c
(so GPL license apply)
Original name of this tool was fdump,
which was conflict with already existing tool,
so name was changed to fmem
Bug reports and patches welcome.
2009,2010 niekt0@hysteria.sk
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Usage:
$ make
# ./run.sh
# dd if=/dev/fmem of=... bs=1MB count=...
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BUGS: if you do something like # dd if=/dev/fmem of=dump
dd will never stop, even if there is no more physical RAM
on the system. This is more a feature, because Linux kernel
don't have stable API, and detection of mapped areas can be
tricky on older kernels. Because primary usage for fmem is
memory forensic, I think it is safer to specify
amount of RAM by hand.
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