From: Anders K. Pedersen <akp@cohaesio.com>
Date: Sat, 29 Oct 2016 09:49:09 +0000 (+0000)
Subject: evaluate: Allow concatenation of rt nexthop etc.
X-Git-Tag: v0.7~51
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=ea9f60be2a31ed06198c22e2cd60d68866d0fdb3;p=thirdparty%2Fnftables.git

evaluate: Allow concatenation of rt nexthop etc.

Concatenations of rt nexthop or ct {orignal | reply} {saddr | daddr} fail
due to

 # nft add rule ip filter postrouting flow table acct \{ ip saddr . rt nexthop counter \}
 <cmdline>:1:61-70: Error: can not use variable sized data types (invalid) in concat expressions
 add rule ip filter postrouting flow table acct { ip saddr . rt nexthop counter }
                                                  ~~~~~~~~~~~^^^^^^^^^^

Fix this by reordering the check for variable size data types in
expr_evaluate_concat() to happen after expr_evaluate() has been called (via
list_member_evaluate()) for the sub expression. This allows
expr_evaluate_[cr]t() to call [cr]t_expr_update_type() and set the data type
before the check.

Signed-off-by: Anders K. Pedersen <akp@cohaesio.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---

diff --git a/src/evaluate.c b/src/evaluate.c
index 79add5ee..878efacd 100644
--- a/src/evaluate.c
+++ b/src/evaluate.c
@@ -987,13 +987,6 @@ static int expr_evaluate_concat(struct eval_ctx *ctx, struct expr **expr)
 						 "expecting %s",
 						 dtype->desc);
 
-		if (dtype == NULL && i->dtype->size == 0)
-			return expr_binary_error(ctx->msgs, i, *expr,
-						 "can not use variable sized "
-						 "data types (%s) in concat "
-						 "expressions",
-						 i->dtype->name);
-
 		if (dtype == NULL)
 			tmp = datatype_lookup(TYPE_INVALID);
 		else
@@ -1004,6 +997,13 @@ static int expr_evaluate_concat(struct eval_ctx *ctx, struct expr **expr)
 			return -1;
 		flags &= i->flags;
 
+		if (dtype == NULL && i->dtype->size == 0)
+			return expr_binary_error(ctx->msgs, i, *expr,
+						 "can not use variable sized "
+						 "data types (%s) in concat "
+						 "expressions",
+						 i->dtype->name);
+
 		ntype = concat_subtype_add(ntype, i->dtype->type);
 	}