src: Allow goto and jump to a variable

This patch introduces the use of nft input files variables in 'jump' and 'goto'
statements, e.g.

define dest = ber

add table ip foo
add chain ip foo bar {type filter hook input priority 0;}
add chain ip foo ber
add rule ip foo ber counter
add rule ip foo bar jump $dest

table ip foo {
        chain bar {
                type filter hook input priority filter; policy accept;
                jump ber
        }

        chain ber {
                counter packets 71 bytes 6664
        }
}

Signed-off-by: Fernando Fernandez Mancera <ffmancera@riseup.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

1 files changed, 11 insertions, 0 deletions

diff --git a/src/datatype.c b/src/datatype.c
index 10f185bc..1d5ed6f7 100644
--- a/src/datatype.c
+++ b/src/datatype.c
@@ -309,11 +309,22 @@ static void verdict_type_print(const struct expr *expr, struct output_ctx *octx)
 	}
 }
 
+static struct error_record *verdict_type_parse(const struct expr *sym,
+					       struct expr **res)
+{
+	*res = constant_expr_alloc(&sym->location, &string_type,
+				   BYTEORDER_HOST_ENDIAN,
+				   (strlen(sym->identifier) + 1) * BITS_PER_BYTE,
+				   sym->identifier);
+	return NULL;
+}
+
 const struct datatype verdict_type = {
 	.type		= TYPE_VERDICT,
 	.name		= "verdict",
 	.desc		= "netfilter verdict",
 	.print		= verdict_type_print,
+	.parse		= verdict_type_parse,
 };
 
 static const struct symbol_table nfproto_tbl = {