Merge branch 'mptcp-pathmanager-api'

Mat Martineau says:

====================
mptcp: Userspace path manager API

Userspace path managers (PMs) make use of generic netlink MPTCP events
and commands to control addition and removal of MPTCP subflows on an
existing MPTCP connection. The path manager events have already been
upstream for a while, and this patch series adds four netlink commands
for userspace:

* MPTCP_PM_CMD_ANNOUNCE: advertise an address that's available for
additional subflow connections.

* MPTCP_PM_CMD_REMOVE: revoke an advertisement

* MPTCP_PM_CMD_SUBFLOW_CREATE: initiate a new subflow on an existing MPTCP
connection

* MPTCP_PM_CMD_SUBFLOW_DESTROY: close a subflow on an existing MPTCP
connection

Userspace path managers, such as mptcpd, can be more easily customized
for different devices. The in-kernel path manager remains available to
handle server use cases.

Patches 1-3 update common path manager code (used by both in-kernel and
userspace PMs)

Patches 4, 6, and 8 implement the new generic netlink commands.

Patches 5, 7, and 9-13 add self test support and test cases for the new
path manager commands.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

include/uapi/linux/mptcp.h

@@ -55,6 +55,9 @@ enum {
 	MPTCP_PM_ATTR_ADDR,				/* nested address */
 	MPTCP_PM_ATTR_RCV_ADD_ADDRS,			/* u32 */
 	MPTCP_PM_ATTR_SUBFLOWS,				/* u32 */
+	MPTCP_PM_ATTR_TOKEN,				/* u32 */
+	MPTCP_PM_ATTR_LOC_ID,				/* u8 */
+	MPTCP_PM_ATTR_ADDR_REMOTE,			/* nested address */
 
 	__MPTCP_PM_ATTR_MAX
 };
@@ -93,6 +96,10 @@ enum {
 	MPTCP_PM_CMD_SET_LIMITS,
 	MPTCP_PM_CMD_GET_LIMITS,
 	MPTCP_PM_CMD_SET_FLAGS,
+	MPTCP_PM_CMD_ANNOUNCE,
+	MPTCP_PM_CMD_REMOVE,
+	MPTCP_PM_CMD_SUBFLOW_CREATE,
+	MPTCP_PM_CMD_SUBFLOW_DESTROY,
 
 	__MPTCP_PM_CMD_AFTER_LAST
 };

net/mptcp/Makefile

@@ -2,7 +2,7 @@
 obj-$(CONFIG_MPTCP) += mptcp.o
 
 mptcp-y := protocol.o subflow.o options.o token.o crypto.o ctrl.o pm.o diag.o \
-	   mib.o pm_netlink.o sockopt.o
+	   mib.o pm_netlink.o sockopt.o pm_userspace.o
 
 obj-$(CONFIG_SYN_COOKIES) += syncookies.o
 obj-$(CONFIG_INET_MPTCP_DIAG) += mptcp_diag.o

net/mptcp/pm.c

@@ -469,6 +469,7 @@ void mptcp_pm_data_init(struct mptcp_sock *msk)
 {
 	spin_lock_init(&msk->pm.lock);
 	INIT_LIST_HEAD(&msk->pm.anno_list);
+	INIT_LIST_HEAD(&msk->pm.userspace_pm_local_addr_list);
 	mptcp_pm_data_reset(msk);
 }
 

net/mptcp/protocol.c

@@ -3097,6 +3097,7 @@ void mptcp_destroy_common(struct mptcp_sock *msk)
 	msk->rmem_fwd_alloc = 0;
 	mptcp_token_destroy(msk);
 	mptcp_pm_free_anno_list(msk);
+	mptcp_free_local_addr_list(msk);
 }
 
 static void mptcp_destroy(struct sock *sk)

net/mptcp/protocol.h

@@ -11,6 +11,7 @@
 #include <net/tcp.h>
 #include <net/inet_connection_sock.h>
 #include <uapi/linux/mptcp.h>
+#include <net/genetlink.h>
 
 #define MPTCP_SUPPORTED_VERSION	1
 
@@ -208,6 +209,7 @@ struct mptcp_pm_data {
 	struct mptcp_addr_info local;
 	struct mptcp_addr_info remote;
 	struct list_head anno_list;
+	struct list_head userspace_pm_local_addr_list;
 
 	spinlock_t	lock;		/*protects the whole PM data */
 
@@ -228,6 +230,14 @@ struct mptcp_pm_data {
 	struct mptcp_rm_list rm_list_rx;
 };
 
+struct mptcp_pm_addr_entry {
+	struct list_head	list;
+	struct mptcp_addr_info	addr;
+	u8			flags;
+	int			ifindex;
+	struct socket		*lsk;
+};
+
 struct mptcp_data_frag {
 	struct list_head list;
 	u64 data_seq;
@@ -601,6 +611,9 @@ void mptcp_subflow_reset(struct sock *ssk);
 void mptcp_sock_graft(struct sock *sk, struct socket *parent);
 struct socket *__mptcp_nmpc_socket(const struct mptcp_sock *msk);
 
+bool mptcp_addresses_equal(const struct mptcp_addr_info *a,
+			   const struct mptcp_addr_info *b, bool use_port);
+
 /* called with sk socket lock held */
 int __mptcp_subflow_connect(struct sock *sk, const struct mptcp_addr_info *loc,
 			    const struct mptcp_addr_info *remote);
@@ -743,6 +756,11 @@ u16 __mptcp_make_csum(u64 data_seq, u32 subflow_seq, u16 data_len, __wsum sum);
 void __init mptcp_pm_init(void);
 void mptcp_pm_data_init(struct mptcp_sock *msk);
 void mptcp_pm_data_reset(struct mptcp_sock *msk);
+int mptcp_pm_parse_addr(struct nlattr *attr, struct genl_info *info,
+			struct mptcp_addr_info *addr);
+int mptcp_pm_parse_entry(struct nlattr *attr, struct genl_info *info,
+			 bool require_family,
+			 struct mptcp_pm_addr_entry *entry);
 void mptcp_pm_subflow_chk_stale(const struct mptcp_sock *msk, struct sock *ssk);
 void mptcp_pm_nl_subflow_chk_stale(const struct mptcp_sock *msk, struct sock *ssk);
 void mptcp_pm_new_connection(struct mptcp_sock *msk, const struct sock *ssk, int server_side);
@@ -763,6 +781,8 @@ void mptcp_pm_rm_addr_received(struct mptcp_sock *msk,
 			       const struct mptcp_rm_list *rm_list);
 void mptcp_pm_mp_prio_received(struct sock *sk, u8 bkup);
 void mptcp_pm_mp_fail_received(struct sock *sk, u64 fail_seq);
+bool mptcp_pm_alloc_anno_list(struct mptcp_sock *msk,
+			      const struct mptcp_pm_addr_entry *entry);
 void mptcp_pm_free_anno_list(struct mptcp_sock *msk);
 bool mptcp_pm_sport_in_anno_list(struct mptcp_sock *msk, const struct sock *sk);
 struct mptcp_pm_add_entry *
@@ -771,14 +791,28 @@ mptcp_pm_del_add_timer(struct mptcp_sock *msk,
 struct mptcp_pm_add_entry *
 mptcp_lookup_anno_list_by_saddr(const struct mptcp_sock *msk,
 				const struct mptcp_addr_info *addr);
-int mptcp_pm_get_flags_and_ifindex_by_id(struct net *net, unsigned int id,
+int mptcp_pm_get_flags_and_ifindex_by_id(struct mptcp_sock *msk,
+					 unsigned int id,
 					 u8 *flags, int *ifindex);
+int mptcp_userspace_pm_get_flags_and_ifindex_by_id(struct mptcp_sock *msk,
+						   unsigned int id,
+						   u8 *flags, int *ifindex);
 
 int mptcp_pm_announce_addr(struct mptcp_sock *msk,
 			   const struct mptcp_addr_info *addr,
 			   bool echo);
 int mptcp_pm_remove_addr(struct mptcp_sock *msk, const struct mptcp_rm_list *rm_list);
 int mptcp_pm_remove_subflow(struct mptcp_sock *msk, const struct mptcp_rm_list *rm_list);
+void mptcp_pm_remove_addrs_and_subflows(struct mptcp_sock *msk,
+					struct list_head *rm_list);
+
+int mptcp_userspace_pm_append_new_local_addr(struct mptcp_sock *msk,
+					     struct mptcp_pm_addr_entry *entry);
+void mptcp_free_local_addr_list(struct mptcp_sock *msk);
+int mptcp_nl_cmd_announce(struct sk_buff *skb, struct genl_info *info);
+int mptcp_nl_cmd_remove(struct sk_buff *skb, struct genl_info *info);
+int mptcp_nl_cmd_sf_create(struct sk_buff *skb, struct genl_info *info);
+int mptcp_nl_cmd_sf_destroy(struct sk_buff *skb, struct genl_info *info);
 
 void mptcp_event(enum mptcp_event_type type, const struct mptcp_sock *msk,
 		 const struct sock *ssk, gfp_t gfp);
@@ -847,6 +881,7 @@ bool mptcp_pm_add_addr_signal(struct mptcp_sock *msk, const struct sk_buff *skb,
 bool mptcp_pm_rm_addr_signal(struct mptcp_sock *msk, unsigned int remaining,
 			     struct mptcp_rm_list *rm_list);
 int mptcp_pm_get_local_id(struct mptcp_sock *msk, struct sock_common *skc);
+int mptcp_userspace_pm_get_local_id(struct mptcp_sock *msk, struct mptcp_addr_info *skc);
 
 void __init mptcp_pm_nl_init(void);
 void mptcp_pm_nl_work(struct mptcp_sock *msk);

net/mptcp/subflow.c

@@ -1468,7 +1468,7 @@ int __mptcp_subflow_connect(struct sock *sk, const struct mptcp_addr_info *loc,
 	if (local_id)
 		subflow_set_local_id(subflow, local_id);
 
-	mptcp_pm_get_flags_and_ifindex_by_id(sock_net(sk), local_id,
+	mptcp_pm_get_flags_and_ifindex_by_id(msk, local_id,
 					     &flags, &ifindex);
 	subflow->remote_key = msk->remote_key;
 	subflow->local_key = msk->local_key;