From: Phil Sutter <phil@nwl.cc>
Date: Mon, 28 May 2018 16:51:03 +0000 (+0200)
Subject: JSON: Simplify tcp option expression parsing a bit
X-Git-Tag: v0.9.0~32
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=bc3e9adc19bc1624010dd478b5e9f006b072298c;p=thirdparty%2Fnftables.git

JSON: Simplify tcp option expression parsing a bit

When parsing the optional "field" property, use return code of
json_unpack() directly to check if it was present or not.

Signed-off-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---

diff --git a/src/parser_json.c b/src/parser_json.c
index f3d2c0f1..bd1c0a04 100644
--- a/src/parser_json.c
+++ b/src/parser_json.c
@@ -479,20 +479,19 @@ static struct expr *json_parse_payload_expr(struct json_ctx *ctx,
 static struct expr *json_parse_tcp_option_expr(struct json_ctx *ctx,
 					       const char *type, json_t *root)
 {
-	const char *desc, *field = NULL;
+	const char *desc, *field;
 	int descval, fieldval;
 	struct expr *expr;
 
 	if (json_unpack_err(ctx, root, "{s:s}", "name", &desc))
 		return NULL;
-	json_unpack(root, "{s:s}", "field", &field);
 
 	if (json_parse_tcp_option_type(desc, &descval)) {
 		json_error(ctx, "Unknown tcp option name '%s'.", desc);
 		return NULL;
 	}
 
-	if (!field) {
+	if (json_unpack(root, "{s:s}", "field", &field)) {
 		expr = tcpopt_expr_alloc(int_loc, descval,
 					 TCPOPTHDR_FIELD_KIND);
 		expr->exthdr.flags = NFT_EXTHDR_F_PRESENT;