evaluate: follow prefix expression recursively if needed

Included bogons assert:
Assertion `!expr_is_constant(*expr) || expr_is_singleton(*expr)' failed

This is because the "foo*" + prefix combination causes expr_evaluate
to replace the binop + string expression with another prefix that
gets allocated while handling "foo*" (wildcard).

This causes expr_evaluate_prefix to build
a prefix -> prefix -> binop chain.

After this, we get:

Error: Right hand side of relational expression ((null)) must be constant
a b ct helper "2.2.2.2.3*1"/80
    ~~~~~~~~~~^^^^^^^^^^^^^^^^
Error: Binary operation (&) is undefined for prefix expressions
a b ct helper "2.2.2.****02"/80
              ^^^^^^^^^^^^^^^^^

for those inputs rather than hitting assert() in byteorder_conversion()
later on.

Signed-off-by: Florian Westphal <fw@strlen.de>

diff --git a/src/evaluate.c b/src/evaluate.c
index ffd3ce6268598921140f58b234a0265b2d40df8a..b984ae4f89b551826724e09f97025d7c3c9f04fc 100644 (file)
--- a/src/evaluate.c
+++ b/src/evaluate.c
@@ -1273,6 +1273,16 @@ static int expr_evaluate_prefix(struct eval_ctx *ctx, struct expr **expr)
        if (expr_evaluate(ctx, &prefix->prefix) < 0)
                return -1;
        base = prefix->prefix;
+
+       /* expr_evaluate may simplify EXPR_AND to another
+        * prefix expression for inputs like "2.2.2.2.3*1"/80.
+        *
+        * Recurse until all the expressions have been simplified.
+        * This also gets us the error checks for the expression
+        * chain.
+        */
+       if (base->etype == EXPR_PREFIX)
+               return expr_evaluate_prefix(ctx, &prefix->prefix);
        assert(expr_is_constant(base));
 
        prefix->dtype     = datatype_get(base->dtype);

diff --git a/tests/shell/testcases/bogons/nft-f/byteorder_conversion_assert b/tests/shell/testcases/bogons/nft-f/byteorder_conversion_assert
new file mode 100644 (file)
index 0000000..26c8914
--- /dev/null
+++ b/tests/shell/testcases/bogons/nft-f/byteorder_conversion_assert
@@ -0,0 +1,2 @@
+a b ct helper "2.2.2.2.3*1"/80
+a b ct helper "2.2.2.****02"/80