rule: Add json parser support

Add function for parsing rules in JSON format

Signed-off-by: Alvaro Neira Ayuso <alvaroneay@gmail.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

1 files changed, 91 insertions, 0 deletions

diff --git a/src/jansson.c b/src/jansson.c
index ca29863..f0ef04c 100644
--- a/src/jansson.c
+++ b/src/jansson.c
@@ -15,6 +15,10 @@
 #include <arpa/inet.h>
 #include <errno.h>
 #include <string.h>
+#include "expr_ops.h"
+
+#include <libnftables/expr.h>
+#include <linux/netfilter/nf_tables.h>
 
 #ifdef JSON_PARSING
 
@@ -121,4 +125,91 @@ int nft_jansson_parse_family(json_t *root, void *out)
 	memcpy(out, &family, sizeof(family));
 	return 0;
 }
+
+int nft_jansson_value_parse_reg(json_t *root, const char *tag, int type,
+				void *out)
+{
+	if (nft_jansson_value_parse_val(root, tag, type, out) != 0)
+		return -1;
+
+	if (*((uint32_t *)out) > NFT_REG_MAX){
+		errno = ERANGE;
+		return -1;
+	}
+
+	return 0;
+}
+
+int nft_jansson_str2num(json_t *root, const char *tag, int base,
+			void *out, enum nft_type type)
+{
+	const char *str;
+
+	str = nft_jansson_value_parse_str(root, tag);
+	if (str == NULL)
+		return -1;
+
+	return nft_strtoi(str, base, out, type);
+}
+
+struct nft_rule_expr *nft_jansson_expr_parse(json_t *root)
+{
+	struct nft_rule_expr *e;
+	const char *type;
+	int ret;
+
+	type = nft_jansson_value_parse_str(root, "type");
+	if (type == NULL)
+		return NULL;
+
+	e = nft_rule_expr_alloc(type);
+	if (e == NULL)
+		return NULL;;
+
+	ret = e->ops->json_parse(e, root);
+
+	return ret < 0 ? NULL : e;
+}
+
+int nft_jansson_data_reg_parse(json_t *root, const char *tag,
+			       union nft_data_reg *data_reg)
+{
+	json_t *data;
+	const char *type;
+	int ret;
+
+	data = json_object_get(root, tag);
+	if (data == NULL) {
+		errno = EINVAL;
+		return -1;
+	}
+
+	data = json_object_get(data, "data_reg");
+	if (data == NULL) {
+		errno = EINVAL;
+		return -1;
+	}
+
+	ret = nft_data_reg_json_parse(data_reg, data);
+
+	if (ret < 0) {
+		errno = EINVAL;
+		return -1;
+	}
+
+	type = nft_jansson_value_parse_str(data, "type");
+	if (type == NULL)
+		return -1;
+
+	if (strcmp(type, "value") == 0)
+		return DATA_VALUE;
+	else if (strcmp(type, "verdict") == 0)
+		return DATA_VERDICT;
+	else if (strcmp(type, "chain") == 0)
+		return DATA_CHAIN;
+	else {
+		errno = EINVAL;
+		return -1;
+	}
+}
 #endif