nat: transform range to prefix expression when possible

This patch transform a range of IP addresses to prefix when listing the
ruleset.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

2 files changed, 7 insertions, 3 deletions

diff --git a/src/netlink.c b/src/netlink.c
index 10964720..bb014320 100644
--- a/src/netlink.c
+++ b/src/netlink.c
@@ -949,7 +949,7 @@ static uint32_t mpz_bitmask_to_prefix(mpz_t bitmask, uint32_t len)
 	return len - mpz_scan0(bitmask, 0);
 }
 
-static struct expr *expr_range_to_prefix(struct expr *range)
+struct expr *range_expr_to_prefix(struct expr *range)
 {
 	struct expr *left = range->left, *right = range->right, *prefix;
 	uint32_t len = left->len, prefix_len;
@@ -989,7 +989,7 @@ static struct expr *netlink_parse_interval_elem(const struct datatype *dtype,
 	range = range_expr_alloc(&expr->location, left, right);
 	expr_free(expr);
 
-	return expr_range_to_prefix(range);
+	return range_expr_to_prefix(range);
 }
 
 static struct expr *netlink_parse_concat_elem(const struct datatype *dtype,
diff --git a/src/netlink_delinearize.c b/src/netlink_delinearize.c
index 772559c8..f721d15c 100644
--- a/src/netlink_delinearize.c
+++ b/src/netlink_delinearize.c
@@ -1103,8 +1103,10 @@ static void netlink_parse_nat(struct netlink_parse_ctx *ctx,
 		else
 			expr_set_type(addr, &ip6addr_type,
 				      BYTEORDER_BIG_ENDIAN);
-		if (stmt->nat.addr != NULL)
+		if (stmt->nat.addr != NULL) {
 			addr = range_expr_alloc(loc, stmt->nat.addr, addr);
+			addr = range_expr_to_prefix(addr);
+		}
 		stmt->nat.addr = addr;
 	}
 
@@ -2296,6 +2298,8 @@ static void expr_postprocess(struct rule_pp_ctx *ctx, struct expr **exprp)
 	case EXPR_RANGE:
 		expr_postprocess(ctx, &expr->left);
 		expr_postprocess(ctx, &expr->right);
+	case EXPR_PREFIX:
+		expr_postprocess(ctx, &expr->prefix);
 		break;
 	case EXPR_SET_ELEM:
 		expr_postprocess(ctx, &expr->key);