src: add input flag NFT_CTX_INPUT_JSON to enable JSON parsing

By default, the input is parsed using the nftables grammar. When setting
NFT_CTX_OUTPUT_JSON flag, nftables will first try to parse the input as
JSON before falling back to the nftables grammar.

But NFT_CTX_OUTPUT_JSON flag also turns on JSON for the output. Add a
flag NFT_CTX_INPUT_JSON which allows to treat only the input as JSON,
but keep the output mode unchanged.

Signed-off-by: Thomas Haller <thaller@redhat.com>
Reviewed-by: Phil Sutter <phil@nwl.cc>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

2 files changed, 6 insertions, 0 deletions

diff --git a/include/nftables.h b/include/nftables.h
index 666a17ae..f073fa95 100644
--- a/include/nftables.h
+++ b/include/nftables.h
@@ -32,6 +32,11 @@ static inline bool nft_input_no_dns(const struct input_ctx *ictx)
 	return ictx->flags & NFT_CTX_INPUT_NO_DNS;
 }
 
+static inline bool nft_input_json(const struct input_ctx *ictx)
+{
+	return ictx->flags & NFT_CTX_INPUT_JSON;
+}
+
 struct output_ctx {
 	unsigned int flags;
 	union {
diff --git a/include/nftables/libnftables.h b/include/nftables/libnftables.h
index e109805f..cc059692 100644
--- a/include/nftables/libnftables.h
+++ b/include/nftables/libnftables.h
@@ -50,6 +50,7 @@ void nft_ctx_set_optimize(struct nft_ctx *ctx, uint32_t flags);
 
 enum {
 	NFT_CTX_INPUT_NO_DNS		= (1 << 0),
+	NFT_CTX_INPUT_JSON		= (1 << 1),
 };
 
 unsigned int nft_ctx_input_get_flags(struct nft_ctx *ctx);