This reverts commit f6cde2d7a6.
gcc detected this header existing and emitted its own limits.h that
included the libc limits.h. This caused the #include_next chain to reach
the end and including the header failed.
Undoing this commit for now until the compiler toolchain is updated to
avoid this problem.
The console has gained these escape codes:
- Set color to any of 256 entries in the palette.
- Set color to any 24-bit RGB value.
- Inverse mode.
- Bold mode.
- Underline mode.
- Move cursor to line N.
- \a is now ignored.
The effectively unused ATTR_CHAR has been removed. Parsing of escape codes
has been improved. The graphical palette has been changed to the tango
colors, which makes Sortix look a bit differently. Some user-space programs
have been changed to use different colors that look better under the new
palette.
Remove const from methods that weren't really const and remove mutable
keyword workaround.
A new ioctl TIOCGDISPLAYS allow detecting which displays the terminal
has associated. The ability to set a keyboard layout can be detected
with tcgetblob kblayout.
Improve the user-space multi-monitor support while here.
The kernel now sets TERM rather than init(8).
This is a compatible ABI change riding on the previous commit's bump.
This change refactors the process group implementation and adds support
for sessions. The setsid(2) and getsid(2) system calls were added.
psctl(2) now has PSCTL_TTYNAME, which lets you get the name of a process's
terminal, and ps(1) now uses it.
The initial terminal is now called /dev/tty1.
/dev/tty is now a factory for the current terminal.
A global lock now protects the process hierarchy which makes it safe to
access other processes. This refactor removes potential vulnerabilities
and increases system robustness.
A number of terminal ioctls have been added.
This is a compatible ABI change.
The bootloader will now load the /boot/random.seed file if it exists, in
which case the kernel will use it as the initial kernel entropy. The kernel
warns if no random seed was loaded, unless the --no-random-seed option was
given. This option is used for live environments that inherently have no
prior secret state. The kernel initializes its entropy pool from the random
seed as of the first things, so randomness is available very early on.
init(8) will emit a fresh /boot/random.seed file on boot to avoid the same
entropy being used twice. init(8) also writes out /boot/random.seed on
system shutdown where the system has the most entropy. init(8) will warn if
writing the file fails, except if /boot is a real-only filesystem, and
keeping such state is impossible. The system administrator is then
responsible for ensuring the bootloader somehow passes a fresh random seed
on the next boot.
/boot/random.seed must be owned by the root user and root group and must
have file permissions 600 to avoid unprivileged users can read it. The file
is passed to the kernel by the bootloader as a multiboot module with the
command line --random-seed.
If no random seed is loaded, the kernel attempts a poor quality fallback
where it seeds the kernel arc4random(3) continuously with the current time.
The timing variance may provide some effective entropy. There is no real
kernel entropy gathering yet. The read of the CMOS real time clock is moved
to an early point in the kernel boot, so the current time is available as
fallback entropy.
The kernel access of the random seed module is supposed to be infallible
and happens before the kernel log is set up, but there is not yet a failsafe
API for mapping single pages in the early kernel.
sysupgrade(8) creates /boot/random.seed if it's absent as a temporary
compatibility measure for people upgrading from the 1.0 release. The GRUB
port will need to be upgraded with support for /boot/random.seed in the
10_sortix script. Installation with manual bootloader configuration will
need to load the random seed with the --random-seed command line. With GRUB,
this can be done with: module /boot/random.seed --random-seed
Add short options for most long options. Rename the -i option to -H, but
support -i for compatibility until the next release cycle, where -i will
become the short option of --identifier. Rename --include to --headers
and support --include until the next release cycle.
Add carray(1) manual page which makes --help unnecessary, and remove
--version as it surely matches your local Sortix version.
This change hardens against invalid calls to sigreturn, which is a very
useful gadget when compromising a process. The system call now verifies
it is a real return from a signal and aborts the process otherwise. This
should render such attacks impossible in threads that are not servicing a
signal, and infeasible in threads that are handling signals they are yet to
return from.
The kernel now keeps track for each thread how many signals are being
handled but haven't returned yet.
Each thread now has a random signal value. It is re-randomized when the
thread handles a signal and the current signal counter is zero. This is
xorred with the context address and used as canary on the stack during
signal dispatch, protecting the saved context on the stack. This works
mostly like the regular stack protector.
The kernel now keeps track of the stack pointer for a single handled
signal per thread. It doesn't seem worth it to keep track of multiple
handled signals, as more than one is rare. Note that each delivered signal
will not necessarily result in a sigreturn because it is valid for a thread
to longjmp(3) out of a signal handler to a valid jmp_buf.
The sigreturn system call will abort if either:
- It was not called from the kernel sigreturn page.
- The thread is not currently processing a signal.
- The thread is processing a single signal, and the stack pointer did not
have the expected value.
- It fails to read the context on the stack.
- The canary is wrong.
Jonas 'Sortie' Termansen
Nicholas De Nova
Meisaka Yukara
Philippe Michaud-Boudreault
Pedro Falcato