diff options
| author | Phil Sutter <phil@nwl.cc> | 2016-11-28 18:51:43 +0100 |
|---|---|---|
| committer | Pablo Neira Ayuso <pablo@netfilter.org> | 2016-11-29 22:49:06 +0100 |
| commit | 7222680eb328b5cebcea78b1dc6ccfacadeaa172 (patch) | |
| tree | 86e176b63816d0b9f0d702fb6398000e60f83309 | |
| parent | ffdcd3fd52f1e87eb99061ec1316f3e8e2f8a4d2 (diff) | |
parser_bison: Allow parens on RHS of relational_expr
This is useful to allow a construct such as:
| tcp flags & (syn|fin) == (syn|fin)
Before, only the parentheses on the left side were allowed, but via a
quite funny path through the parser:
* expr might be a concat_expr
* concat_expr might be a basic_expr
* basic_expr is an inclusive_or_expr
* inclusive_or_expr might be an exclusive_or_expr
* exclusive_or_expr might be an and_expr
* and_expr might be 'and_expr AMPERSAND shift_expr'
-> here we eliminate 'flags &' in above statement
* shift_expr might be a primary_expr
* primary_expr might be '( basic_expr )'
Commit a3e60492a684b ("parser: restrict relational rhs expression
recursion") introduced rhs_expr to disallow recursion on RHS, so just
reverting that change for relational_expr is a no go. Allowing rhs_expr
to be '( rhs_expr )' though seems way too intrusive to me since it's
being used in all kinds of places, so this patch is the safest way to
allow the above I could come up with.
Signed-off-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
| -rw-r--r-- | src/parser_bison.y | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/src/parser_bison.y b/src/parser_bison.y index 981ffc81..f07303e2 100644 --- a/src/parser_bison.y +++ b/src/parser_bison.y @@ -2302,6 +2302,10 @@ relational_expr : expr /* implicit */ rhs_expr { $$ = relational_expr_alloc(&@2, $2, $1, $3); } + | expr relational_op '(' rhs_expr ')' + { + $$ = relational_expr_alloc(&@2, $2, $1, $4); + } ; list_rhs_expr : basic_rhs_expr COMMA basic_rhs_expr |