patch 9.0.1968: cmdline completion should consider key option
Problem: cmdline completion should consider key option
Solution: Disable cmdline completion for key option, slightly
refactor how P_NO_CMD_EXPAND is handled
Harden crypto 'key' option: turn off cmdline completion, disable set-=
"set-=" can be used maliciously with a crypto key, as it allows an
attacker (who either has access to the computer or a plugin author) to
guess a substring by observing the modified state. Simply turn off
set+=/-=/^= for this option as there is no good reason for them to be
used.
Update docs to make that clear as well.
Also, don't allow cmdline completion for 'key' as it just shows *****
which is not useful and confusing to the user what it means (if the user
accidentally hits enter they will have replaced their key with "*****"
instead).
Move logic to better location, don't use above 32-bit for flags
Move P_NO_CMD_EXPAND to use the unused 0x20 instead of going above
32-bits, as currently the flags parameter is only 32-bits on some
systems. Left a comment to warn that future additions will need to
change how the flags work either by making it 64-bit or split into two
member vars.
Also, move the logic for detecting P_NO_CMD_EXPAND earlier so it's not
up to each handler to decide, and you won't see the temporary "..." that
Vim shows while waiting for completion handler to complete.
closes: #13224
Signed-off-by: Christian Brabandt <cb@256bit.org>
Co-authored-by: Yee Cheng Chin <ychin.git@gmail.com>
diff --git a/src/option.h b/src/option.h
index ced4f3e..396c568 100644
--- a/src/option.h
+++ b/src/option.h
@@ -25,6 +25,7 @@
// the same.
#define P_EXPAND 0x10 // environment expansion. NOTE: P_EXPAND can
// never be used for local or hidden options!
+#define P_NO_CMD_EXPAND 0x20 // don't perform cmdline completions
#define P_NODEFAULT 0x40 // don't set to default value
#define P_DEF_ALLOCED 0x80 // default value is in allocated memory, must
// use vim_free() when assigning new value
@@ -61,6 +62,10 @@
#define P_MLE 0x20000000L // under control of 'modelineexpr'
#define P_FUNC 0x40000000L // accept a function reference or a lambda
#define P_COLON 0x80000000L // values use colons to create sublists
+// Warning: Currently we have used all 32 bits for option flags. On some 32-bit
+// systems, the flags are stored as a 32-bit integer, and adding more
+// flags will overflow it. Adding another flag will need to change how
+// it's stored first.
// Returned by get_option_value().
typedef enum {