vt: make the default color configurable
Subsystems (2)
PATCH 1/1 vt: make the default color configurable
The virtual console has (undocumented) module parameters to set the colors for italic and underlined text, but the default text color was hardcoded for some reason. This made it impossible to change the color for startup messages, or to set the default for new virtual consoles. Add a module parameter for that, and document the entire bunch.
Any hacker who thinks that a command prompt on a "black screen with white font" is not supicious enough can now use the kernel parameter vt.color=10 to get a nice, evil green.
Signed-off-by Clemens Ladisch <[email protected]>
--- Documentation/kernel-parameters.txt | 10 ++++++++++ drivers/tty/vt/vt.c | 4 +++- 2 files changed, 13 insertions(+), 1 deletion(-)
Changing the background color looks ugly because the cute penguin logo is designed for a black background; somebody ought to implement alpha blending ...
Documentation/kernel-parameters.txt +10 -0
@@ -3322,6 +3322,10 @@ bytes respectively. Such letter suffixes can also be entirely omitted. them quite hard to use for exploits but might break your system. + vt.color= [VT] Default text color. + Format: 0xYX, X = foreground, Y = background. + Default: 0x07 = light gray on black. + vt.cur_default= [VT] Default cursor shape. Format: 0xCCBBAA, where AA, BB, and CC are the same as the parameters of the <Esc>[?A;B;Cc escape sequence;
@@ -3361,6 +3365,12 @@ bytes respectively. Such letter suffixes can also be entirely omitted. overridden by individual drivers. 0 will hide cursors, 1 will display them. + vt.italic= [VT] Default color for italic text; 0-15. + Default: 2 = green. + + vt.underline= [VT] Default color for underlined text; 0-15. + Default: 3 = cyan. + watchdog timers [HW,WDT] For information on watchdog timers, see Documentation/watchdog/watchdog-parameters.txt or other driver-specific files in the
drivers/tty/vt/vt.c +3 -1
@@ -2809,8 +2809,10 @@ static void con_shutdown(struct tty_struct *tty)console_unlock (); } +static int default_color =7 ;/* white */ static int default_italic_color =2 ;// green (ASCII) static int default_underline_color =3 ;// cyan (ASCII) +module_param_named (color, default_color, int,S_IRUGO |S_IWUSR );module_param_named (italic, default_italic_color, int,S_IRUGO |S_IWUSR );module_param_named (underline, default_underline_color, int,S_IRUGO |S_IWUSR );
@@ -2832,7 +2834,7 @@ static void vc_init(struct vc_data *vc, unsigned int rows, vc->vc_palette[k++] = default_grn[j] ; vc->vc_palette[k++] = default_blu[j] ; } - vc->vc_def_color =0x07 ;/* white */ + vc->vc_def_color = default_color; vc->vc_ulcolor = default_underline_color; vc->vc_itcolor = default_italic_color; vc->vc_halfcolor =0x08 ;/* grey */