See:
https://edc.intel.com/content/www/us/en/design/ipla/software-development-platforms/client/platforms/alder-lake-mobile-p/intel-600-series-chipset-family-on-package-platform-controller-hub-pch-datash/spi0-for-flash/
The rules described there are universal, and replicated elsewhere
for many other platforms. The rules are simply:
* Flash descriptor is one block size, e.g. 4KB
* GbE is two block sizes, so if IfD is 4KB, GbE is 8KB
Intel defines 16KB and 128KB GbE files in specs, pertaining to
8KB and 64KB block sizes respectively.
The minimum size is 4KB blocksize, for 8KB GbE files which
we already supported. On larger block sizes, the same 4KB
parts are observed: a single 4KB IfD area at the start of
the block, and:
4KB GbE part at the start of the GbE region, and:
4KB GbE part at the start of GbE region plus block size
The empty space inbetween is padding, and we ignore it,
except when running swap/copy commands.
The nvmutil code has been modified, to create a 128KB buffer in
memory instead of 8KB, for loading GbE files.
Partsize is set to GbE file size divided by 2, and only the
area of memory we need to use is mapped; for example, if
we're loading a 8KB GbE file into memory, we only touch
the first 8KB part of the buffer, or first 16KB for 128KB
files.
In practise, we almost never see GbE files with sizes higher
than 8KB, but *we have seen it*, *AND NOW IT'S SUPPORTED!"
Signed-off-by: Leah Rowe <leah@libreboot.org>
We were checking directories *after* calling unveil, which
means that the sandboxing was incomplete; we only want files
to be accessed, not directories.
Signed-off-by: Leah Rowe <leah@libreboot.org>
A lot of size-coding was performed in prior audits, to
make the sloccount lower on nvmutil, but this resulted in
code that wasn't very human readable.
I've reversed some of it and added comments, for clarity.
Signed-off-by: Leah Rowe <leah@libreboot.org>
Mention Riku's copyright in the COPYING file, and update
my years in that file. Add Riku to the AUTHORS file.
Signed-off-by: Leah Rowe <leah@libreboot.org>
The user might wish to uninstall, but not remove the
build that they just did.
The user can still do make clean if they wish.
Signed-off-by: Leah Rowe <leah@libreboot.org>
DESTDIR is the root directory where it goes, which
is normally an empty string; PREFIX is where the
bin directory is located, relative to DESTDIR
Default to /usr/local for PREFIX, not /usr, because
/usr/bin is for system utilities.
nvmutil is a local utility.
Signed-off-by: Leah Rowe <leah@libreboot.org>
We don't want to clobber anything that the user set themselves.
Instead, we should respect the user's choice.
Signed-off-by: Leah Rowe <leah@libreboot.org>
This makes the code easier to understand.
All 2-byte words, stored in little endian order within
the 128-byte GbE NVM area, must add up to 0xBABA.
If it doesn't, then software is supposed to reject that
GbE config. The nvmutil software works on that basis.
Signed-off-by: Leah Rowe <leah@libreboot.org>
make it look like hexdump -C, where individual bytes are
spaced, and there is an additional space after 8 bytes,
per row.
i won't bother with a character display, since that is
meaningless on gbe nvm words.
Signed-off-by: Leah Rowe <leah@libreboot.org>
Must not exceed 79 lines. Some variables and functions have
been renamed, and there has been some minor re-factoring.
Signed-off-by: Leah Rowe <leah@libreboot.org>
I don't like using SPDX for actual copyright declarations.
I only want it to be used for the license identifier.
Also:
I made a *single* change to nvmutil.c in 2024, which means
that I have copyright in all years since and including 2022;
the file said 2022, 2023, 2025, but it's actually 2022-2025.
Signed-off-by: Leah Rowe <leah@libreboot.org>
under the current logic, errno would be ECANCELED
if neither checksum is valid, or I/O related if
pwrite fails; alternatively, the for loop exits
and the file has been written, where it is quite
correctly reset already.
ergo, the errno reset at the start of
writeGbeFile is superfluous. remove this bloat.
Signed-off-by: Leah Rowe <leah@libreboot.org>
previously, a bad checksum would have caused a non-zero
exit, even if the other checksum was correct (observed
when using the swap command)
Signed-off-by: Leah Rowe <leah@libreboot.org>
at this stage in the code, the file name will be NULL
value, so it would be improper to use it in a string.
Signed-off-by: Leah Rowe <leah@libreboot.org>
the previous code size optimisations removed mention
of the file name, on file-related err() calls.
almost every error the user runs across will be file
related, so put the path on err() called from err_if()
Signed-off-by: Leah Rowe <leah@libreboot.org>
there is no need to have these as defines, when err_if
exists; get rid of xunveil and xpledge. use the bare
pledge and unveil functions directly, with err_if().
268 sloccount now on nvmutil.c, versus 289 sloccount
before this change, with no loss of functionality.
Signed-off-by: Leah Rowe <leah@libreboot.org>
it doesn't really make sense to have nvmutil.h
since this is only a very small program and not
intended for use as a library
Signed-off-by: Leah Rowe <leah@libreboot.org>
The mentality behind pledge and unveil is that you should
think ahead, so that large parts of code can run under
extremely tight restrictions.
The pledge calls have been adjusted accordingly, also.
Disallow all unveil calls after the gbe file and the
file /dev/urandom have been unveiled.
Signed-off-by: Leah Rowe <leah@libreboot.org>
Leah Rowe
Riku Viitanen