Previously, base64dec checked terminating input '\0' every 4 calls to
base64dec_getc, where the latter progressed one or more chars on each
call, and could read past '\0' in the way it was used.
The input to base64dec currently comes only from OSC 52 escape seq
(copy to clipboard), and reading past '\0' or even past the buffer
boundary was easy to trigger.
Also, even if we could trust external input to be valid base64, there
are different base64 standards, and not all of them require padding
to 4 bytes blocks (using trailing '=' chars).
It didn't affect short OSC 52 strings because the buffer is initialized
to 0's, so typically it did stop within the buffer, but if the string
was trimmed to fit (the buffer is 512 bytes) then it did also read past
the end of the buffer, and the decoded suffix ended up arbitrary.
This patch makes base64dec_getc not progress past '\0', and instead
produce fake trailing padding of '='.
Additionally, at base64dec, if padding is detected at the first or
second byte of a quartet, then we identify it as invalid and abort
(a valid quartet has at least two leading non-padding bytes).
The recent mouse shurtcuts commits allow customization, but ignore
forcemousemod mask (default: shift) as a modifier, for no good reason
other than following the behavior of the KB shortcuts.
Allow using forcemousemod too, which now can be used to invoke
different shortcuts, though the automatic effect of forcemousemod will
be lost for buttons which use mask with forcemousemod.
E.g. the default is:
static uint forcemousemod = ShiftMask;
...
{ XK_ANY_MOD, Button4, ttysend, {.s = "\031"} },
...
where ttysend will be invoked for button4 with any mod when not in mouse
mode, and with shift when in mouse mode.
Now it's possible to do this:
{ ShiftMask, Button4, ttysend, {.s = "foo"} },
{ XK_ANY_MOD, Button4, ttysend, {.s = "\031"} },
Which will invoke ttysend("foo") while shift is held and ttysend("\031")
otherwise. Shift still overrides mouse mode, but will now send "foo".
Previously with this setup the second binding was always invoked
because the forceousemod mask was always removed from the event.
Buttons which don't use forcemousemod behave the same as before.
This is useful e.g. for the scrollback mouse patch, which wants to
configure shift+wheel for scrollback, while keeping the normal behavior
without shift.
Because selpaste is activated on release, a release flag was added to
mouse shortcuts which controls whether activation is on press/release,
and selpaste binding to button2 was moved to config.h .
button1 remains the only hardcoded mouse button - for selection + copy.
Allow forceselmod to override all mouse shortcuts rather than only
selection, and rename it to forcemousemod as it's now more appropriate.
This will affect mouse shortcuts which use mask other than XK_ANY_MOD.
This does not affect the default behavior because the default mouse
shortcuts (wheel) use XK_ANY_MOD, where forceselmod already activated
the override also before this change.
Previously, if a mouse shortcut was configured with a specific mod and
forceselmod was held, then the shortcut did not execute unless the
configured mod included forceselmod.
Avi Halachmi (:avih)andHiltjo Posthuma