loader.interpret should not be used for executing loader commands from an
untrusted source (e.g. environment vars) as it will allow execution of
arbitrary Lua. Replace it with a call to the recently introduced
cli_execute_unparsed, which parses it out as a loader command and then
dispatches it as a loader command. This effectively filters out arbitrary
Lua.
This will be used for scenarios where the command to execute is coming in
via the environment (from, for example, loader.conf(5)) and is thus not
necessarily trusted.
cli_execute_unparsed will immediately be used for handling
module_{before,after,error} as well as menu_timeout_command. We still want
to offer these variables the ability to execute Lua-intercepted loader
commands, but we don't want them to be able to execute arbitrary Lua.
Reviewed by: imp
Differential Revision: https://reviews.freebsd.org/D14580
Back when I "fixed" the loading of kernel/modules to be deferred until
booting, I inadvertently broke the ability to manually load a set of kernels
and modules in case of something bad having happened. lualoader would
instead happily load whatever is specified in loader.conf(5) and go about
the boot, leading to a panic loop as you try to rediscover a way to stop the
panicky efirt module from loading and fail miserably.
Reported by: me, sadly
loader.command(...) will return whatever the executed function returns, so
follow suit and return whatever loader.command() returned or whatever the
Lua function returns.
- All of our default positions were offset from forth
- Our menu frame size was smaller than in forth
- Logo/brand drawing had an off-by-one, drawing one column lower on the
screen than they should have been.
- While here, switch a print() to printc() as it's expected that logos may
contain color and other escpae sequences that we'll need to honor.
It may be set to "left" or "right" -- any other value will cause the title
to be centered.
I've chosen to position these things just inside the vertical borders,
rather than overlapping the corners. This is an arbitrary choice and easily
amendable if this looks terrible.
Rather than before the menu is drawn. The drawer is going to reset the
crusor position as soon as it draws anything anyways, so doing it before
serves no purpose. Setting it after is needed so we don't clobber the menu
when we start booting.
r330282 registered loader.printc as printc, so use it instead. This makes
sense for a couple reasons, the major point being that it reads a little bit
easier and pairs nicely with the global 'print'.
Similar cases can not really be made for other loader.* functions as most of
them are either highly specific to our use-case or usually available in
other modules, such as `os`. printc does not have a standard implementation
in the Lua world(*), so we have a little more leeway with it, and it's kind
of a special case of the globally available 'print'.
(*) I've been in the Lua world for all of two weeks, so this could be wrong.
- Add drawer.frame_styles to map out the kinds of characters we need for the
different loader_menu_frame values
- Respect loader_menu_frame, default to double[*]
- (imp) Use loader.printc instead of print- print adds a newline to the
output, which is not the right thing we want to be doing.
- (imp) Draw horizontal frames a little more efficiently- setting the cursor
after every line segment is horribly inefficient, especially on serial
consoles. Halve the number of characters written at the expense of an
additional loop to draw the bottom frame, which is likely more efficient
in the long run for some of less ideal scenarios.
[*] menu.4th(8) claims that the default here was single, but unset
loader_menu_frame yielded double and we didn't have any overrides in the
default loader.conf(5), so double it is.
Distribution will be done after all of the lualoader manpages are created.
Reviewed by: rpokala
Differential Revision: https://reviews.freebsd.org/D14480
Distribution will be done after all of the lualoader manpages are created.
Reviewed by: rpokala
Differential Revision: https://reviews.freebsd.org/D14479
Rather than hardcoding these things. This could lead to some form of loader
localization later, but the main goal at the moment is to get a clear view
of the strings we're outputting and strive to use more string.format() and
less wild concatenation all over the place.
We've included an extra '0' in there (which might get removed later, but
it's maintained for the moment for legacy purposes) which oftentimes
indicate that the following number should be treated as octal. This is not
the case, so note that to prevent future confusion (of myself and others).
Our module bits ended up more stable than I anticipated, so this turns out
to be no longer useful.
If things like this need to come back, we should do it in a separate 'debug'
module to serve as a collection of debugging aides. As a rule, this 'debug'
module would *not* be allowed as a requirement of any other modules in-tree.
- Add screen.default_x and screen.default_y to determine where
screen.defcursor resets the cursor to.
- Use screen.setcursor in screen.defcursor instead of rewriting the escape
sequence.
- Use screen.default_y when resetting the cursor after writing the new
twiddle character, add a comment verbally describing the position just in
case.
It worked on my test setup, but is clearly non-functional on others.
Further examination of check-password.4th showed that it actually reset the
cursor to 0,25 every time and overwrote the previous password prompt. Do
that, and also clear the "Incorrect Password" text if the correct password
gets entered.
twiddle_pos didn't need to be a module-scope local, since it's going to get
reset with every read anyways- it was left-over from other things.
screen.movecursor with a y=-1 setting was from a test of movecursor,
resulting in the twiddle characters being drawn going up the console and
looking quite funky.
This gives some form of feedback while typing, and matches-(ish*) Forth
behavior. The cursor generally rests two column after the password prompt,
then the twiddle is drawn three columns later and the cursor reset to
resting position after being drawn.
I've removed the note about re-evaluating it for security considerations and
instead set it up as a module-local variable that we can set later depending
on environment or something. It's set to false with no chance of changing at
the moment.
*As close as I can tell from reading check-password.4th, because I don't
have an easy test (or deployed) setup for forth loader to check how close
it is. Please do mention if it's not close enough.
This is motivated by a want to reduce heap usage if the menu is being
skipped. Currently, the menu module must be loaded regardless of whether
it's being skipped or not, which adds a cool ~50-100KB worth of memory
usage.
Move the menu skip logic out to core (and remove a debug print), then check
in loader.lua if we should be skipping the menu and avoid loading the menu
module entirely if so. This keeps our memory usage below ~115KB for a boot
with the menu stripped.
Also worth noting: with this change, we no longer explicitly invoke autoboot
if we're skipping the menu. Instead, we let the standard loader behavior
apply: try to autoboot if we need to, then drop to a loader prompt if not or
if the autoboot sequence is interrupted. The only thing we still handle
before dropping to the loader autoboot sequence is loadelf(), so that we can
still apply any of our kernel loading behavior.
screen was also guilty of not-so-great argument names, but it was also
guilty of handling color sequences on its own. Change those bits to using
the color module instead.
As a side note, between color and screen, I'm not 100% sure that returning
the color_value is the right thing to do if we won't generate the escape
sequences. This should be re-evaluated at a later time, and they should
likely return nil instead.
Instead of a single-letter parameter ('m'), use something a little more
descriptive and meaningful: 'menudef' ("menu definition") -- these functions
expect to be passed a menudef, so call it what it is.
While here, throw an assertion in that we have a handler for the selected
menu item. This is more of a debugging aide so that it's more obvious when
one is testing a menudef that they've added an entry item that we don't
handle.
This is an improvement over the past behavior of ignoring the unknown menu
entry.
This cleans up the odd approach to menu drawing. Instead of tracking
validity, we track the menu that was drawn on the screen. Whenever we draw a
menu, we'll set this to that menu.
Anything that invalidates the screen should go ahead and trigger an explicit
redraw, rather than finding a wy to set screen_invalid.
The currently drawn menu is then reset in menu.run as we exit the menu
system, so that dropping to the loader prompt or leaving menu.run() will
just behave as expected without doing redundant work every time we leave a
menu.
In the common case, this will effectively do nothing as the menu will get
redrawn as we leave submenus regardless of whether the screen has been
marked invalid or not
However, upon escape to the loader prompt, one could do either of the
following to re-enter the menu system:
-- Method 1
require('menu').run()
-- Method 2
require('menu').process(menu.default)
With method 1, the menu will get redrawn anyways as we do this before
autoboot checking upon entry. With method 2, however, the menu will not be
redrawn without this invalidation.
Both methods are acceptable for re-entering the menu system, although the
latter method in the local module for processing new and interesting menus
is more expected.
cli_execute is likely the only exception that we should make, due to it
being a global. We don't really need other globals, so this won't really end
up an epidemic.
There's no reason for autoboot handling to be mixed in with menu processing.
It is a distinct process that should only be done once when entering the
menu system.
menu.process has been modified to take an initial keypress to process and to
only draw the screen initially if it's been invalidated. The keypress is
kind of a kludge, although it could be argued to be a potentially useful
kludge if there are other processes that may need to feed a keypress into
the menu system.
In general, every menu redraw is going to require a screen clear and cursor
reset. Each redraw also has the potential to invalidate the alias table, so
we move the alias table being used out into a module variable. This allows
third party consumers to also inspect or update the alias table if they need
to.
While here, stop searching the alias table once we've found a match.
This is driven by an urge to separate out the bits that really only need to
happen when the menu system starts up. Key points:
- menu.process now does the bulk of menu handling. It retains autoboot
handling for dubious reasons, and it no longer accepts a 'nil' menu to
process as 'the default'. Its return value is insignificant.
- The MENU_SUBMENU handler now returns nothing. If menu.process has exited,
then we continue processing menu items on the parent menu as expected.
- menu.run is now the entry point of the menu system. It checks whether the
menu should be skipped, processes the default menu, then returns.
These indices were assigned the same values as they would've been implicitly
assigned anyways.
While here, throw terminating commas after the last value of tables.
It should use the common parser, but it should not be processed like a
standard file. Rewite check_nextboot to read the file in, check whether it
should continue, then parse as needed.
This allows us to throw the recently introduced check_and_halt callback
swiftly out the window.
config.parse is now purely a parser, rather than a whole proccessor. The
standard process for loading a config file has been split out into
config.processFile.
This clears the way for having nextboot read its own config file and decide
there whether it should parse the rest of the file.
This is step 1 towards revoking config.parse of it I/O privileges. Ideally,
all reading would be done before config.parse and config.parse would just
take text and parse it rather than being charged with the entire process.