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, 77 insertions, 0 deletions

diff --git a/src/expr/data_reg.c b/src/expr/data_reg.c
index 4c354ef..d0e1a83 100644
--- a/src/expr/data_reg.c
+++ b/src/expr/data_reg.c
@@ -26,6 +26,83 @@
 #include "data_reg.h"
 #include "internal.h"
 
+#ifdef JSON_PARSING
+static int nft_data_reg_verdict_json_parse(union nft_data_reg *reg, json_t *data)
+{
+	int verdict;
+	const char *verdict_str;
+
+	verdict_str = nft_jansson_value_parse_str(data, "verdict");
+	if (verdict_str == NULL)
+		return -1;
+
+	verdict = nft_str2verdict(verdict_str);
+	if (verdict < 0)
+		return -1;
+
+	reg->verdict = (uint32_t)verdict;
+
+	return 0;
+}
+
+static int nft_data_reg_chain_json_parse(union nft_data_reg *reg, json_t *data)
+{
+	reg->chain = strdup(nft_jansson_value_parse_str(data, "chain"));
+	if (reg->chain == NULL) {
+		return -1;
+	}
+
+	return 0;
+}
+
+static int nft_data_reg_value_json_parse(union nft_data_reg *reg, json_t *data)
+{
+	int i;
+	char node_name[6];
+
+	if (nft_jansson_value_parse_val(data, "len", NFT_TYPE_U8,
+					&reg->len) != 0)
+			return -1;
+
+	for (i = 0; i < div_round_up(reg->len, sizeof(uint32_t)); i++) {
+		sprintf(node_name, "data%d", i);
+
+		if (nft_jansson_str2num(data, node_name, BASE_HEX,
+				        &reg->val[i], NFT_TYPE_U32) != 0)
+			return -1;
+	}
+
+	return 0;
+}
+#endif
+
+int nft_data_reg_json_parse(union nft_data_reg *reg, json_t *data)
+{
+#ifdef JSON_PARSING
+
+	const char *type;
+
+	type = nft_jansson_value_parse_str(data, "type");
+	if (type == NULL) {
+		return -1;
+	}
+
+	/* Select what type of parsing is needed */
+	if (strcmp(type, "value") == 0) {
+		return nft_data_reg_value_json_parse(reg, data);
+	} else if (strcmp(type, "verdict") == 0) {
+		return nft_data_reg_verdict_json_parse(reg, data);
+	} else if (strcmp(type, "chain") == 0) {
+		return nft_data_reg_chain_json_parse(reg, data);
+	}
+
+	return 0;
+#else
+	errno = EOPNOTSUPP;
+	return -1;
+#endif
+}
+
 #ifdef XML_PARSING
 static int nft_data_reg_verdict_xml_parse(union nft_data_reg *reg, char *xml)
 {