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/testdir/test_crypt.vim b/src/testdir/test_crypt.vim
index 1782d83..85ed574 100644
--- a/src/testdir/test_crypt.vim
+++ b/src/testdir/test_crypt.vim
@@ -438,4 +438,27 @@
bwipe!
endfunc
+func Test_crypt_set_key_disallow_append_subtract()
+ new Xtest4
+
+ set key=foobar
+ call assert_true(&modified)
+ setl nomodified
+
+ call assert_fails('set key-=foo', 'E474:')
+ call assert_fails('set key-=bar', 'E474:')
+ call assert_fails('set key-=foobar', 'E474:')
+ call assert_fails('set key-=test1', 'E474:')
+
+ call assert_false(&modified)
+ call assert_equal('*****', &key)
+
+ call assert_fails('set key+=test2', 'E474:')
+ call assert_fails('set key^=test3', 'E474:')
+
+ call assert_false(&modified)
+ set key=
+ bwipe!
+endfunc
+
" vim: shiftwidth=2 sts=2 expandtab