src: remove version from XML and JSON representations

This patch removes the version XML node and the version JSON field
in all our existing objects. The current versioning approach
consists of adding a version field to every object representation
in XML and JSON. While listing my entire rule-set, one can notice
that this approach is too bloated.

Once the library enters stable stage, if we need to obsolete a XML
node and a JSON field, we can follow this procedure:

1) Remove the XML node and the JSON field from the output, so fresh
   outputs will not contain the old ones anymore.

2) Do not remove the parsing of the old XML node and the JSON field
   inmediately. We have to keep supporting the parsing for a while
   to avoid breaking the interpretion of old XML/JSON files. We can
   spot a warning to warn about it, so users generate a fresh
   output again.

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

5 files changed, 13 insertions, 84 deletions

diff --git a/src/chain.c b/src/chain.c
index 1e07044..14db5f7 100644
--- a/src/chain.c
+++ b/src/chain.c
@@ -475,7 +475,6 @@ static int nft_chain_xml_parse(struct nft_chain *c, char *xml)
 	mxml_node_t *node = NULL;
 	char *endptr = NULL;
 	uint64_t utmp;
-	int64_t tmp;
 	int family;
 
 	/* NOTE: all XML nodes are mandatory */
@@ -485,17 +484,6 @@ static int nft_chain_xml_parse(struct nft_chain *c, char *xml)
 	if (tree == NULL)
 		return -1;
 
-	/* Validate version */
-	if (mxmlElementGetAttr(tree, "version") == NULL) {
-		mxmlDelete(tree);
-		return -1;
-	}
-	tmp = strtoll(mxmlElementGetAttr(tree, "version"), &endptr, 10);
-	if (tmp == LLONG_MAX || *endptr || tmp != NFT_CHAIN_XML_VERSION) {
-		mxmlDelete(tree);
-		return -1;
-	}
-
 	/* Get and set <chain name="xxx" ... >*/
 	if (mxmlElementGetAttr(tree, "name") == NULL) {
 		mxmlDelete(tree);
@@ -694,13 +682,12 @@ static int nft_chain_snprintf_json(char *buf, size_t size, struct nft_chain *c)
 			"\"handle\": %"PRIu64","
 			"\"bytes\": %"PRIu64","
 			"\"packets\": %"PRIu64","
-			"\"version\": %d,"
 			"\"properties\": {"
 				"\"family\": \"%s\","
 				"\"table\": \"%s\","
 				"\"use\": %d",
 			c->name, c->handle, c->bytes, c->packets,
-			NFT_CHAIN_JSON_VERSION, nft_family2str(c->family),
+			nft_family2str(c->family),
 			c->table, c->use);
 		SNPRINTF_BUFFER_SIZE(ret, size, len, offset);
 
@@ -730,7 +717,7 @@ static int nft_chain_snprintf_xml(char *buf, size_t size, struct nft_chain *c)
 
 	ret = snprintf(buf, size,
 		       "<chain name=\"%s\" handle=\"%"PRIu64"\""
-		       " bytes=\"%"PRIu64"\" packets=\"%"PRIu64"\" version=\"%d\">"
+		       " bytes=\"%"PRIu64"\" packets=\"%"PRIu64"\">"
 		       "<properties>"
 				"<type>%s</type>"
 				"<table>%s</table>"
@@ -738,7 +725,7 @@ static int nft_chain_snprintf_xml(char *buf, size_t size, struct nft_chain *c)
 				"<use>%d</use>"
 				"<hooknum>%s</hooknum>",
 		       c->name, c->handle, c->bytes, c->packets,
-		       NFT_CHAIN_XML_VERSION, c->type, c->table,
+		       c->type, c->table,
 		       c->prio, c->use, hooknum2str_array[c->hooknum]);
 	SNPRINTF_BUFFER_SIZE(ret, size, len, offset);
 
diff --git a/src/internal.h b/src/internal.h
index 1970c9c..a8ae431 100644
--- a/src/internal.h
+++ b/src/internal.h
@@ -47,15 +47,6 @@ const char *nft_jansson_value_parse_str(json_t *root, const char *tag);
 bool nft_jansson_node_exist(json_t *root, const char *tag);
 #endif
 
-#define NFT_TABLE_XML_VERSION 0
-#define NFT_CHAIN_XML_VERSION 0
-#define NFT_RULE_XML_VERSION 0
-#define NFT_SET_XML_VERSION 0
-#define NFT_TABLE_JSON_VERSION 0
-#define NFT_CHAIN_JSON_VERSION 0
-#define NFT_RULE_JSON_VERSION 0
-#define NFT_SET_JSON_VERSION 0
-
 const char *nft_family2str(uint32_t family);
 int nft_str2family(const char *family);
 int nft_strtoi(const char *string, int base, void *number, enum nft_type type);
diff --git a/src/rule.c b/src/rule.c
index c3cc75a..11737e5 100644
--- a/src/rule.c
+++ b/src/rule.c
@@ -486,17 +486,6 @@ static int nft_rule_xml_parse(struct nft_rule *r, char *xml)
 	if (tree == NULL)
 		return -1;
 
-	/* validate XML version <rule ... version=X ... > */
-	if (mxmlElementGetAttr(tree, "version") == NULL) {
-		mxmlDelete(tree);
-		return -1;
-	}
-	tmp = strtoll(mxmlElementGetAttr(tree, "version"), &endptr, 10);
-	if (tmp == LLONG_MAX || *endptr || tmp != NFT_RULE_XML_VERSION) {
-		mxmlDelete(tree);
-		return -1;
-	}
-
 	/* get and set <rule ... family=X ... > */
 	if (mxmlElementGetAttr(tree, "family") == NULL) {
 		mxmlDelete(tree);
@@ -644,10 +633,9 @@ static int nft_rule_snprintf_json(char *buf, size_t size, struct nft_rule *r,
 
 	ret = snprintf(buf, size,
 				"{ \"rule\": { \"family\" : \"%s\", \"table\" : \"%s\", "
-				"\"chain\"  : \"%s\", \"handle\" : %llu, \"version\" : %d, ",
+				"\"chain\"  : \"%s\", \"handle\" : %llu,",
 				nft_family2str(r->family), r->table, r->chain,
-				(unsigned long long)r->handle,
-				NFT_RULE_JSON_VERSION);
+				(unsigned long long)r->handle);
 	SNPRINTF_BUFFER_SIZE(ret, size, len, offset);
 
 	ret = snprintf(buf+offset, len, "\"rule_flags\" : %u, ",
@@ -690,10 +678,9 @@ static int nft_rule_snprintf_xml(char *buf, size_t size, struct nft_rule *r,
 
 	ret = snprintf(buf, size,
 		"<rule family=\"%s\" table=\"%s\" "
-			"chain=\"%s\" handle=\"%llu\" version=\"%d\">",
+			"chain=\"%s\" handle=\"%llu\">",
 				nft_family2str(r->family), r->table, r->chain,
-				(unsigned long long)r->handle,
-				NFT_RULE_XML_VERSION);
+				(unsigned long long)r->handle);
 	SNPRINTF_BUFFER_SIZE(ret, size, len, offset);
 
 	ret = snprintf(buf+offset, len, "<rule_flags>%u</rule_flags>",
diff --git a/src/set.c b/src/set.c
index 4b0ec6a..23a2ab1 100644
--- a/src/set.c
+++ b/src/set.c
@@ -311,7 +311,6 @@ static int nft_set_xml_parse(struct nft_set *s, char *xml)
 	struct nft_set_elem *elem;
 	char *name;
 	char *table;
-	int version;
 	int family;
 	char *family_str;
 
@@ -324,13 +323,6 @@ static int nft_set_xml_parse(struct nft_set *s, char *xml)
 	if (strcmp(tree->value.opaque, "set") != 0)
 		goto err;
 
-	if (nft_mxml_num_parse(tree, "set_xml_version", MXML_DESCEND_FIRST,
-			       BASE_DEC, &version, NFT_TYPE_S32) != 0)
-		goto err;
-
-	if (version != NFT_SET_XML_VERSION)
-		goto err;
-
 	name = (char *)nft_mxml_str_parse(tree, "set_name",
 					  MXML_DESCEND_FIRST);
 	if (name == NULL)
@@ -448,10 +440,10 @@ static int nft_set_snprintf_json(char *buf, size_t size, struct nft_set *s,
 	struct nft_set_elem *elem;
 
 	ret = snprintf(buf, size, "{ \"set\": { \"name\": \"%s\","
-				  "\"table\": \"%s\",\"version\": %d,"
+				  "\"table\": \"%s\","
 				  "\"flags\": %u,\"family\": \"%s\","
 				  "\"key_type\": %u,\"key_len\": %u",
-			s->name, s->table, NFT_SET_JSON_VERSION, s->set_flags,
+			s->name, s->table, s->set_flags,
 			nft_family2str(s->family), s->key_type, s->key_len);
 	SNPRINTF_BUFFER_SIZE(ret, size, len, offset);
 
@@ -529,14 +521,13 @@ static int nft_set_snprintf_xml(char *buf, size_t size, struct nft_set *s,
 	ret = snprintf(buf, size, "<set><family>%s</family>"
 				  "<set_table>%s</set_table>"
 				  "<set_name>%s</set_name>"
-				  "<set_xml_version>%d</set_xml_version>"
 				  "<set_flags>%u</set_flags>"
 				  "<key_type>%u</key_type>"
 				  "<key_len>%u</key_len>"
 				  "<data_type>%u</data_type>"
 				  "<data_len>%u</data_len>",
 			nft_family2str(s->family), s->table, s->name,
-			NFT_SET_XML_VERSION,  s->set_flags, s->key_type,
+			s->set_flags, s->key_type,
 			s->key_len, s->data_type, s->data_len);
 	SNPRINTF_BUFFER_SIZE(ret, size, len, offset);
 
diff --git a/src/table.c b/src/table.c
index 1d17d3b..1f4fe76 100644
--- a/src/table.c
+++ b/src/table.c
@@ -223,8 +223,6 @@ static int nft_table_xml_parse(struct nft_table *t, char *xml)
 #ifdef XML_PARSING
 	mxml_node_t *tree = NULL;
 	mxml_node_t *node = NULL;
-	char *endptr = NULL;
-	int64_t stmp;
 	int family;
 
 	/* NOTE: all XML nodes are mandatory */
@@ -234,18 +232,6 @@ static int nft_table_xml_parse(struct nft_table *t, char *xml)
 	if (tree == NULL)
 		return -1;
 
-	/* Check the version of the XML */
-	if (mxmlElementGetAttr(tree, "version") == NULL) {
-		mxmlDelete(tree);
-		return -1;
-	}
-
-	stmp = strtoll(mxmlElementGetAttr(tree, "version"), &endptr, 10);
-	if (stmp == LLONG_MAX || *endptr || stmp != NFT_TABLE_XML_VERSION) {
-		mxmlDelete(tree);
-		return -1;
-	}
-
 	/* Get and set the name of the table */
 	if (mxmlElementGetAttr(tree, "name") == NULL) {
 		mxmlDelete(tree);
@@ -300,7 +286,6 @@ static int nft_table_json_parse(struct nft_table *t, char *json)
 #ifdef JSON_PARSING
 	json_t *root;
 	json_error_t error;
-	uint64_t version;
 	uint32_t table_flag;
 	const char *str;
 	int family;
@@ -317,15 +302,6 @@ static int nft_table_json_parse(struct nft_table *t, char *json)
 		goto err;
 	}
 
-	if (nft_jansson_value_parse_val(root, "version",
-					NFT_TYPE_U64, &version) == -1)
-		goto err;
-
-	if (version != NFT_TABLE_JSON_VERSION) {
-		errno = EINVAL;
-		goto err;
-	}
-
 	str = nft_jansson_value_parse_str(root, "name");
 	if (str == NULL)
 		goto err;
@@ -392,27 +368,24 @@ static int nft_table_snprintf_json(char *buf, size_t size, struct nft_table *t)
 	return snprintf(buf, size,
 			"{\"table\" : {"
 			"\"name\" : \"%s\","
-			"\"version\" : %d,"
 			"\"properties\" : {"
 				"\"family\" : \"%s\","
 				"\"table_flags\" : %d"
 				"}"
 			"}"
 			"}" ,
-			t->name, NFT_TABLE_JSON_VERSION,
-			nft_family2str(t->family), t->table_flags);
+			t->name, nft_family2str(t->family), t->table_flags);
 }
 
 static int nft_table_snprintf_xml(char *buf, size_t size, struct nft_table *t)
 {
-	return snprintf(buf, size, "<table name=\"%s\" version=\"%d\">"
+	return snprintf(buf, size, "<table name=\"%s\">"
 				"<properties>"
 					"<family>%s</family>"
 					"<table_flags>%d</table_flags>"
 				"</properties>"
 				"</table>",
-		       t->name, NFT_TABLE_XML_VERSION,
-		       nft_family2str(t->family), t->table_flags);
+		       t->name, nft_family2str(t->family), t->table_flags);
 }
 
 static int nft_table_snprintf_default(char *buf, size_t size, struct nft_table *t)