This patch adds [,resourcecontrol=deny] to `-sandbox on' option. It
blacklists all process affinity and scheduler priority system calls to
avoid any bigger of the process.
Signed-off-by: Eduardo Otubo <otubo@redhat.com>

This patch adds [,spawn=deny] argument to `-sandbox on' option. It
blacklists fork and execve system calls, avoiding Qemu to spawn new
threads or processes.
Signed-off-by: Eduardo Otubo <otubo@redhat.com>

This patch introduces the new argument
[,elevateprivileges=allow|deny|children] to the `-sandbox on'. It allows
or denies Qemu process to elevate its privileges by blacklisting all
set*uid|gid system calls. The 'children' option will let forks and
execves run unprivileged.
Signed-off-by: Eduardo Otubo <otubo@redhat.com>

This patch introduces the argument [,obsolete=allow] to the `-sandbox on'
option. It allows Qemu to run safely on old system that still relies on
old system calls.
Signed-off-by: Eduardo Otubo <otubo@redhat.com>

This patch changes the default behavior of the seccomp filter from
whitelist to blacklist. By default now all system calls are allowed and
a small black list of definitely forbidden ones was created.
Signed-off-by: Eduardo Otubo <otubo@redhat.com>

Clean up includes so that osdep.h is included first and headers
which it implies are not included manually.

This commit was created with scripts/clean-includes.

NB: If this commit breaks compilation for your out-of-tree
patchseries or fork, then you need to make sure you add
#include "qemu/osdep.h" to any new .c files that you have.
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Eric Blake <eblake@redhat.com>

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Signed-off-by: Eduardo Otubo <otubo@linux.vnet.ibm.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
---
v1:
 - I added a syscall struct using priority levels as described in the
   libseccomp man page. The priority numbers are based to the frequency
   they appear in a sample strace from a regular qemu guest run under
   libvirt.

   Libseccomp generates linear BPF code to filter system calls, those rules
   are read one after another. The priority system places the most common
   rules first in order to reduce the overhead when processing them.

v1 -> v2:
 - Fixed some style issues
 - Removed code from vl.c and created qemu-seccomp.[ch]
 - Now using ARRAY_SIZE macro
 - Added more syscalls without priority/frequency set yet

v2 -> v3:
 - Adding copyright and license information
 - Replacing seccomp_whitelist_count just by ARRAY_SIZE
 - Adding header protection to qemu-seccomp.h
 - Moving QemuSeccompSyscall definition to qemu-seccomp.c
 - Negative return from seccomp_start is fatal now.
 - Adding open() and execve() to the whitelis

v3 -> v4:
 - Tests revealed a bigger set of syscalls.
 - seccomp_start() now has an argument to set the mode according to the
   configure option trap or kill.

v4 -> v5:
 - Tests on x86_64 required a new specific set of system calls.
 - libseccomp release 1.0.0: part of the API have changed in this last
   release, had to adapt to the new function signatures.