diff options
| author | Adam Borowski <kilobyte@angband.pl> | 2014-02-19 01:38:04 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2014-02-28 16:25:47 -0800 |
| commit | 63f3a16db915096d7a80a96748adba00feb07a32 (patch) | |
| tree | 131d7ba0b5809848aa71728b107b57d3e54fd28d /drivers/tty/vt/vt.c | |
| parent | b290af68de57196e7cb34805f41cd3416ed1a791 (diff) | |
vt: detect and ignore OSC codes.
These can be used to send commands consisting of an arbitrary string to the
terminal, most often used to set a terminal's window title or to redefine
the colour palette. Our console doesn't use OSC, unlike everything else,
which can lead to junk being displayed if a process sends such a code
unconditionally.
The rules for termination follow established practice rather than Ecma-48.
Ecma-48 requires the string to use only byte values 0x08..0x0D and
0x20..0x7E, terminated with either ESC \ or 0x9C. This would disallow using
8-bit characters, which are reasonable for example in window titles.
A widespread idiom is to terminate with 0x07. The behaviour for other
control characters differs between terminal emulators, I followed libvte and
xterm:
* 0x07 and ESC anything terminate
* nothing else terminates, all 8-bit values including 0x9C are considered a
part of the string
Signed-off-by: Adam Borowski <kilobyte@angband.pl>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty/vt/vt.c')
| -rw-r--r-- | drivers/tty/vt/vt.c | 14 |
1 files changed, 11 insertions, 3 deletions
diff --git a/drivers/tty/vt/vt.c b/drivers/tty/vt/vt.c index b7bde54db138..3ad0b61e35b4 100644 --- a/drivers/tty/vt/vt.c +++ b/drivers/tty/vt/vt.c @@ -1592,7 +1592,7 @@ static void restore_cur(struct vc_data *vc) enum { ESnormal, ESesc, ESsquare, ESgetpars, ESfunckey, EShash, ESsetG0, ESsetG1, ESpercent, ESignore, ESnonstd, - ESpalette }; + ESpalette, ESosc }; /* console_lock is held (except via vc_init()) */ static void reset_terminal(struct vc_data *vc, int do_clear) @@ -1652,11 +1652,15 @@ static void do_con_trol(struct tty_struct *tty, struct vc_data *vc, int c) * Control characters can be used in the _middle_ * of an escape sequence. */ + if (vc->vc_state == ESosc && c>=8 && c<=13) /* ... except for OSC */ + return; switch (c) { case 0: return; case 7: - if (vc->vc_bell_duration) + if (vc->vc_state == ESosc) + vc->vc_state = ESnormal; + else if (vc->vc_bell_duration) kd_mksound(vc->vc_bell_pitch, vc->vc_bell_duration); return; case 8: @@ -1767,7 +1771,9 @@ static void do_con_trol(struct tty_struct *tty, struct vc_data *vc, int c) } else if (c=='R') { /* reset palette */ reset_palette(vc); vc->vc_state = ESnormal; - } else + } else if (c>='0' && c<='9') + vc->vc_state = ESosc; + else vc->vc_state = ESnormal; return; case ESpalette: @@ -2021,6 +2027,8 @@ static void do_con_trol(struct tty_struct *tty, struct vc_data *vc, int c) vc->vc_translate = set_translate(vc->vc_G1_charset, vc); vc->vc_state = ESnormal; return; + case ESosc: + return; default: vc->vc_state = ESnormal; } |