kParser: Multi-namespace support

include/net/kparser.h

@@ -32,6 +32,8 @@
  *            data path.
  *
  * return: kParser error code as defined in include/uapi/linux/kparser.h
+ * NOTE: This API supports multiple networking namespaces by using the skb's
+ * "struct net" member.
  */
 extern int kparser_parse(struct sk_buff *skb,
 			 const struct kparser_hkey *kparser_key,
@@ -96,12 +98,91 @@ extern const void *kparser_get_parser(const struct kparser_hkey *kparser_key,
  */
 extern bool kparser_put_parser(const void *parser, bool avoid_ref);
 
+/* __kparser_parse_ns(): Function to parse a void * packet buffer using a parser instance key
+ *
+ * The only difference between __kparser_parse_ns() and __kparser_parse() is,
+ * __kparser_parse_ns() supports multiple namespaces if "struct net" parameter
+ * is provided. If not, then there is no difference between these two APIs.
+ *
+ * net: the net structure from which namespace can be obtained using kernel API
+ * get_net(). If passed NULL, then no namespace will be used.
+ * parser: Non NULL kparser_get_parser() returned and cached opaque pointer
+ * referencing a valid parser instance.
+ * _hdr: input packet buffer
+ * parse_len: length of input packet buffer
+ * _metadata: User provided metadata buffer. It must be same as configured
+ * metadata objects in CLI.
+ * metadata_len: Total length of the user provided metadata buffer.
+ *
+ * return: kParser error code as defined in include/uapi/linux/kparser.h
+ */
+extern int __kparser_parse_ns(struct net *net, const void *parser, void *_hdr,
+			      size_t parse_len, void *_metadata, size_t metadata_len);
+
+/* kparser_get_parser_ns(): Function to get an opaque reference of a parser instance and mark it
+ * immutable so that while actively using, it can not be deleted. The parser is identified by a key.
+ * It marks the associated parser and whole parse tree immutable so that when it is locked, it can
+ * not be deleted.
+ *
+ * The only difference between kparser_get_parser_ns() and kparser_get_parser() is,
+ * kparser_get_parser_ns() supports multiple namespaces if "struct net" parameter
+ * is provided. If not, then there is no difference between these two APIs.
+ *
+ * net: the net structure from which namespace can be obtained using kernel API
+ * get_net(). If passed NULL, then no namespace will be used.
+ * kparser_key: key of the associated kParser parser object which must be
+ * already created via CLI.
+ * avoid_ref: Set this flag in case caller wants to avoid holding the reference
+ *            of the active parser object to save performance on the data path.
+ *            But please be advised, caller should hold the reference of the
+ *            parser object while using this data path. In this case, the CLI
+ *            can be used in advance to get the reference, and caller will also
+ *            need to release the reference via CLI once it is done with the
+ *            data path.
+ *
+ * return: NULL if key not found, else an opaque parser instance pointer which
+ * can be used in the following APIs 3 and 4.
+ *
+ * NOTE: This call makes the whole parser tree immutable. If caller calls this
+ * more than once, later caller will need to release the same parser exactly that
+ * many times using the API kparser_put_parser().
+ */
+extern const void *kparser_get_parser_ns(struct net *net,
+					 const struct kparser_hkey *kparser_key,
+					 bool avoid_ref);
+
+/* kparser_put_parser_ns(): Function to return and undo the read only operation done previously by
+ * kparser_get_parser(). The parser instance is identified by using a previously obtained opaque
+ * parser pointer via API kparser_get_parser(). This undo the immutable change so that any component
+ * of the whole parse tree can be deleted again.
+ *
+ * The only difference between kparser_put_parser_ns() and kparser_put_parser() is,
+ * kparser_put_parser_ns() supports multiple namespaces if "struct net" parameter
+ * is provided. If not, then there is no difference between these two APIs.
+ *
+ * net: the net structure from which namespace can be obtained using kernel API
+ * get_net(). If passed NULL, then no namespace will be used.
+ * parser: void *, Non NULL opaque pointer which was previously returned by kparser_get_parser().
+ * Caller can use cached opaque pointer as long as system does not restart and kparser.ko is not
+ * reloaded.
+ * avoid_ref: Set this flag only when this was used in the prio call to
+ *            kparser_get_parser(). Incorrect usage of this flag might cause
+ *            error and make the parser state unstable.
+ *
+ * return: boolean, true if put operation is success, else false.
+ *
+ * NOTE: This call makes the whole parser tree deletable for the very last call.
+ */
+extern bool kparser_put_parser_ns(struct net *net,
+				  const void *parser, bool avoid_ref);
+
 /* net/core/filter.c's callback hook structure to use kParser APIs if kParser enabled */
 struct get_kparser_funchooks {
 	const void * (*kparser_get_parser_hook)(const struct kparser_hkey
 						*kparser_key, bool avoid_ref);
 	int (*__kparser_parse_hook)(const void *parser, void *_hdr,
-				    size_t parse_len, void *_metadata, size_t metadata_len);
+				    size_t parse_len, void *_metadata,
+				    size_t metadata_len);
 	bool (*kparser_put_parser_hook)(const void *parser, bool avoid_ref);
 };
 

include/net/net_namespace.h

@@ -188,6 +188,10 @@ struct net {
 #if IS_ENABLED(CONFIG_SMC)
 	struct netns_smc	smc;
 #endif
+
+#if IS_ENABLED(CONFIG_KPARSER)
+	void			*kparser_ns;
+#endif
 } __randomize_layout;
 
 #include <linux/seq_file_net.h>

include/uapi/linux/kparser.h

@@ -205,6 +205,8 @@ struct kparser_conf_metadata {
 	size_t add_off;
 	struct kparser_hkey counterkey;
 	struct kparser_hkey counter_data_key;
+	__u8 right_shift;
+	__u32 mask;
 };
 
 /* *********************** metadata list/table *********************** */

net/kparser/kparser.h

@@ -277,19 +277,23 @@ static inline __u32 kparser_generic_obj_hashfn_id(const void *obj, __u32 key_len
 /* internal shared functions */
 int kparser_init(void);
 int kparser_deinit(void);
-int kparser_config_handler_add(const void *cmdarg, size_t cmdarglen,
+int kparser_config_handler_add(void *netns,
+			       const void *cmdarg, size_t cmdarglen,
 			       struct kparser_cmd_rsp_hdr **rsp,
 			       size_t *rsp_len,
 			       void *extack, int *err);
-int kparser_config_handler_update(const void *cmdarg, size_t cmdarglen,
+int kparser_config_handler_update(void *netns,
+				  const void *cmdarg, size_t cmdarglen,
 				  struct kparser_cmd_rsp_hdr **rsp,
 				  size_t *rsp_len,
 				  void *extack, int *err);
-int kparser_config_handler_read(const void *cmdarg, size_t cmdarglen,
+int kparser_config_handler_read(void *netns,
+				const void *cmdarg, size_t cmdarglen,
 				struct kparser_cmd_rsp_hdr **rsp,
 				size_t *rsp_len,
 				void *extack, int *err);
-int kparser_config_handler_delete(const void *cmdarg, size_t cmdarglen,
+int kparser_config_handler_delete(void *netns,
+				  const void *cmdarg, size_t cmdarglen,
 				  struct kparser_cmd_rsp_hdr **rsp,
 				  size_t *rsp_len,
 				  void *extack, int *err);
@@ -312,16 +316,17 @@ int kparser_namespace_insert(enum kparser_global_namespace_ids ns_id,
 			     struct rhash_head *obj_name);
 
 /* Generic kParser KMOD's netlink msg handler's definitions for create */
-typedef int kparser_obj_create_update(const struct kparser_conf_cmd *conf,
+typedef int kparser_obj_create_update(void *netns,
+				      const struct kparser_conf_cmd *conf,
 				      size_t conf_len,
 				      struct kparser_cmd_rsp_hdr **rsp,
 				      size_t *rsp_len, const char *op,
 				      void *extack, int *err);
 /* Generic kParser KMOD's netlink msg handler's definitions for read and delete */
-typedef int kparser_obj_read_del(const struct kparser_hkey *key,
-		struct kparser_cmd_rsp_hdr **rsp,
-		size_t *rsp_len, __u8 recursive_read,
-		const char *op, void *extack, int *err);
+typedef int kparser_obj_read_del(void *netns, const struct kparser_hkey *key,
+				 struct kparser_cmd_rsp_hdr **rsp,
+				 size_t *rsp_len, __u8 recursive_read,
+				 const char *op, void *extack, int *err);
 /* Generic kParser KMOD's netlink msg handler's free callbacks */
 typedef void kparser_free_obj(void *ptr, void *arg);
 int kparser_link_attach(const void *owner_obj,
@@ -415,4 +420,25 @@ do {										\
 }										\
 while (0)
 
+/* kParser KMOD's namespace definitions */
+struct kparser_mod_namespaces {
+	enum kparser_global_namespace_ids namespace_id;
+	const char *name;
+	struct kparser_htbl htbl_name;
+	struct kparser_htbl htbl_id;
+	kparser_obj_create_update *create_handler;
+	kparser_obj_create_update *update_handler;
+	kparser_obj_read_del *read_handler;
+	kparser_obj_read_del *del_handler;
+	kparser_free_obj *free_handler;
+	size_t bv_len;
+	unsigned long *bv;
+};
+
+struct kparser_ns_ds_ctx {
+	struct kparser_mod_namespaces **kparser_ns_ctx;
+};
+
+struct kparser_ns_ds_ctx * kparser_alloc_global_ns_ctx(void);
+
 #endif /* __KPARSER_H */