When printing list of allowed syscalls the width of terminal is
obtained for nicer output (see commit below). The width is
obtained by running 'stty'. While this works when building from a
console, it doesn't work during rpmbuild/emerge/.. as stdout is
usually not a console but a logfile and stdin is usually
/dev/null or something. This results in stty reporting errors
like this:

  stty: 'standard input': Inappropriate ioctl for device

Redirect stty's stderr to /dev/null to silence it.

Fixes: 712ca3235329 ("seccomp.sh: Try to account for terminal width while formatting list of system calls")
Signed-off-by: Michal Privoznik <mprivozn@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>

A privileged helper to set/clear TCP_REPAIR on sockets on behalf of
passt. Not used yet.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>

Currently we construct the AUDIT_ARCH variable in the Makefile, then pass
it into the C code with -D.  The only place that uses it, though is the
BPF filter generated by seccomp.sh.  seccomp.sh already needs to do things
differently depending on the arch, so it might as well just insert the
expanded AUDIT_ARCH directly into the generated code, rather than using
a #define.  Arguably this is better, even, since it ensures more locally
that the arch the BPF checks for matches the arch seccomp.sh built the
filter for.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>

Avoid excess lines on wide terminals, but make sure we don't fail if
we can't fetch the number of columns for any reason, as it's not a
fundamental feature and we don't want to break anything with it.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>

Currently "make cppcheck" invokes cppcheck on ".", so it will check all the
.c and .h files it can find in the source tree.  This isn't ideal, because
it can find files that aren't actually part of the real build, or even
stale files which aren't in git.

More practically, some upcoming changes are looking at downloading other
source trees for some tests.  Static errors in there is Not Our Problem,
so checking them is both slow and pointless.

So, change the Makefile to invoke cppcheck only on the specific source
files that are part of the build.  For some reason in this format the
badBitmaskCheck warnings in seccomp.h which were suppressed by 5beb3472e
("cppcheck: Avoid errors due to zeroes in bitwise ORs") no longer trigger.
That means we get unmatchedSuppression warnings instead.  We add an
unmatchedSuppression suppression instead of simply removing the original
suppressions, just in case this odd behaviour isn't the same for all
cppcheck versions.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>

seccomp.sh generates seccomp.h piece by piece using >> directives.  This
means that if two instances of seccomp.h are run concurrently a corrupted
version of seccomp.h will be generated. Amongst other problems this can
cause spurious failures on clang-tidy.

Alter seccomp.sh to build the output in a temporary file and atomic move it
to seccomp.h, so concurrent invocations will still result in valud output.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>

In practical terms, passt doesn't benefit from the additional
protection offered by the AGPL over the GPL, because it's not
suitable to be executed over a computer network.

Further, restricting the distribution under the version 3 of the GPL
wouldn't provide any practical advantage either, as long as the passt
codebase is concerned, and might cause unnecessary compatibility
dilemmas.

Change licensing terms to the GNU General Public License Version 2,
or any later version, with written permission from all current and
past contributors, namely: myself, David Gibson, Laine Stump, Andrea
Bolognani, Paul Holzinger, Richard W.M. Jones, Chris Kuhn, Florian
Weimer, Giuseppe Scrivano, Stefan Hajnoczi, and Vasiliy Ulyanov.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>

Debian cross-building automatic checks:

  http://crossqa.debian.net/src/passt

currently fail because we don't use the right target architecture and
compiler while building the system call lists and resolving their
numbers in seccomp.sh. Pass ARCH and CC to seccomp.sh and use them.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>

Recent versions of cppcheck give warnings if using a bitwise OR (|) where
some of the arguments are zero.  We're triggering these warnings in our
generated seccomp.h header, because BPF_LD and BPF_W are zero-valued.
However putting these defines in makes the generate code clearer, even
though they could be left out without changing the values.  So, add
cppcheck suppressions to the generated code.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>

The passt/pasta Makefile makes fairly heavy use of GNU make's $(wildcard)
function to locate the sources and headers to build.  Using wildcards for
the things to compile is usually a bad idea though: if somehow you end up
with a .c or .h file in your tree you didn't expect it can misbuild in an
exceedingly confusing way.  In particular this can sometimes happen if
switching between releases / branches where files have been added or
removed without 100% cleaning the tree.

It also makes life a bit complicated if building multiple different
binaries in the same tree: we already have some rather awkward
$(filter-out) constructions to avoid including qrap.c in the passt build.

Replace use of $(wildcard) with the more idiomatic approach of defining
variables listing all the relevant source files then using that throughout.
In the rule for seccomp.h there was also a bare "*.c" which caused make to
always rebuild that target.  Fix that as well.

Similarly, seccomp.sh uses a wildcard to locate the sources, which is
unwise for the same reasons.  Make it take the sources to examine on the
command line instead, and have the Makefile pass them in from the same
variables.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>