Merge branch 'mptcp-convert-netlink-code-to-use-yaml-spec'

Mat Martineau says:

====================
mptcp: convert Netlink code to use YAML spec

This series from Davide converts most of the MPTCP Netlink interface
(plus uAPI bits) to use sources generated by YNL using a YAML spec file.

This new YAML file is useful to validate the API and to generate a good
documentation page.

Patch 1 modifies YNL spec to support "uns-admin-perm" for genetlink
legacy.

Patch 2 adds support for validating exact length of netlink attrs.

Patch 3 converts Netlink structures from small_ops to ops to prepare the
switch to YAML.

Patch 4 adds the Netlink YAML spec for MPTCP.

Patch 5 adds and uses a new header file generated from the new YAML
spec.

Patch 6 renames some handlers to match the ones generated from the YAML
spec.

Patch 7 adds and uses Netlink policies automatically generated from the
YAML spec.
====================

Link: https://lore.kernel.org/r/20231023-send-net-next-20231023-1-v2-0-16b1f701f900@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

2 files changed, 160 insertions, 164 deletions

diff --git a/include/uapi/linux/mptcp.h b/include/uapi/linux/mptcp.h
index ee9c49f949a2..64ecc8a3f9f2 100644
--- a/include/uapi/linux/mptcp.h
+++ b/include/uapi/linux/mptcp.h
@@ -23,91 +23,24 @@
 #define MPTCP_SUBFLOW_FLAG_CONNECTED		_BITUL(7)
 #define MPTCP_SUBFLOW_FLAG_MAPVALID		_BITUL(8)
 
-enum {
-	MPTCP_SUBFLOW_ATTR_UNSPEC,
-	MPTCP_SUBFLOW_ATTR_TOKEN_REM,
-	MPTCP_SUBFLOW_ATTR_TOKEN_LOC,
-	MPTCP_SUBFLOW_ATTR_RELWRITE_SEQ,
-	MPTCP_SUBFLOW_ATTR_MAP_SEQ,
-	MPTCP_SUBFLOW_ATTR_MAP_SFSEQ,
-	MPTCP_SUBFLOW_ATTR_SSN_OFFSET,
-	MPTCP_SUBFLOW_ATTR_MAP_DATALEN,
-	MPTCP_SUBFLOW_ATTR_FLAGS,
-	MPTCP_SUBFLOW_ATTR_ID_REM,
-	MPTCP_SUBFLOW_ATTR_ID_LOC,
-	MPTCP_SUBFLOW_ATTR_PAD,
-	__MPTCP_SUBFLOW_ATTR_MAX
-};
-
-#define MPTCP_SUBFLOW_ATTR_MAX (__MPTCP_SUBFLOW_ATTR_MAX - 1)
-
-/* netlink interface */
-#define MPTCP_PM_NAME		"mptcp_pm"
 #define MPTCP_PM_CMD_GRP_NAME	"mptcp_pm_cmds"
 #define MPTCP_PM_EV_GRP_NAME	"mptcp_pm_events"
-#define MPTCP_PM_VER		0x1
-
-/*
- * ATTR types defined for MPTCP
- */
-enum {
-	MPTCP_PM_ATTR_UNSPEC,
-
-	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
-};
-
-#define MPTCP_PM_ATTR_MAX (__MPTCP_PM_ATTR_MAX - 1)
-
-enum {
-	MPTCP_PM_ADDR_ATTR_UNSPEC,
-
-	MPTCP_PM_ADDR_ATTR_FAMILY,			/* u16 */
-	MPTCP_PM_ADDR_ATTR_ID,				/* u8 */
-	MPTCP_PM_ADDR_ATTR_ADDR4,			/* struct in_addr */
-	MPTCP_PM_ADDR_ATTR_ADDR6,			/* struct in6_addr */
-	MPTCP_PM_ADDR_ATTR_PORT,			/* u16 */
-	MPTCP_PM_ADDR_ATTR_FLAGS,			/* u32 */
-	MPTCP_PM_ADDR_ATTR_IF_IDX,			/* s32 */
-
-	__MPTCP_PM_ADDR_ATTR_MAX
-};
-
-#define MPTCP_PM_ADDR_ATTR_MAX (__MPTCP_PM_ADDR_ATTR_MAX - 1)
-
-#define MPTCP_PM_ADDR_FLAG_SIGNAL			(1 << 0)
-#define MPTCP_PM_ADDR_FLAG_SUBFLOW			(1 << 1)
-#define MPTCP_PM_ADDR_FLAG_BACKUP			(1 << 2)
-#define MPTCP_PM_ADDR_FLAG_FULLMESH			(1 << 3)
-#define MPTCP_PM_ADDR_FLAG_IMPLICIT			(1 << 4)
 
-enum {
-	MPTCP_PM_CMD_UNSPEC,
+#include <linux/mptcp_pm.h>
 
-	MPTCP_PM_CMD_ADD_ADDR,
-	MPTCP_PM_CMD_DEL_ADDR,
-	MPTCP_PM_CMD_GET_ADDR,
-	MPTCP_PM_CMD_FLUSH_ADDRS,
-	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
-};
+/* for backward compatibility */
+#define	__MPTCP_PM_CMD_AFTER_LAST	__MPTCP_PM_CMD_MAX
+#define	__MPTCP_ATTR_AFTER_LAST		__MPTCP_ATTR_MAX
 
 #define MPTCP_INFO_FLAG_FALLBACK		_BITUL(0)
 #define MPTCP_INFO_FLAG_REMOTE_KEY_RECEIVED	_BITUL(1)
 
+#define MPTCP_PM_ADDR_FLAG_SIGNAL                      (1 << 0)
+#define MPTCP_PM_ADDR_FLAG_SUBFLOW                     (1 << 1)
+#define MPTCP_PM_ADDR_FLAG_BACKUP                      (1 << 2)
+#define MPTCP_PM_ADDR_FLAG_FULLMESH                    (1 << 3)
+#define MPTCP_PM_ADDR_FLAG_IMPLICIT                    (1 << 4)
+
 struct mptcp_info {
 	__u8	mptcpi_subflows;
 	__u8	mptcpi_add_addr_signal;
@@ -130,93 +63,6 @@ struct mptcp_info {
 	__u64	mptcpi_bytes_acked;
 };
 
-/*
- * MPTCP_EVENT_CREATED: token, family, saddr4 | saddr6, daddr4 | daddr6,
- *                      sport, dport
- * A new MPTCP connection has been created. It is the good time to allocate
- * memory and send ADD_ADDR if needed. Depending on the traffic-patterns
- * it can take a long time until the MPTCP_EVENT_ESTABLISHED is sent.
- *
- * MPTCP_EVENT_ESTABLISHED: token, family, saddr4 | saddr6, daddr4 | daddr6,
- *			    sport, dport
- * A MPTCP connection is established (can start new subflows).
- *
- * MPTCP_EVENT_CLOSED: token
- * A MPTCP connection has stopped.
- *
- * MPTCP_EVENT_ANNOUNCED: token, rem_id, family, daddr4 | daddr6 [, dport]
- * A new address has been announced by the peer.
- *
- * MPTCP_EVENT_REMOVED: token, rem_id
- * An address has been lost by the peer.
- *
- * MPTCP_EVENT_SUB_ESTABLISHED: token, family, loc_id, rem_id,
- *                              saddr4 | saddr6, daddr4 | daddr6, sport,
- *                              dport, backup, if_idx [, error]
- * A new subflow has been established. 'error' should not be set.
- *
- * MPTCP_EVENT_SUB_CLOSED: token, family, loc_id, rem_id, saddr4 | saddr6,
- *                         daddr4 | daddr6, sport, dport, backup, if_idx
- *                         [, error]
- * A subflow has been closed. An error (copy of sk_err) could be set if an
- * error has been detected for this subflow.
- *
- * MPTCP_EVENT_SUB_PRIORITY: token, family, loc_id, rem_id, saddr4 | saddr6,
- *                           daddr4 | daddr6, sport, dport, backup, if_idx
- *                           [, error]
- * The priority of a subflow has changed. 'error' should not be set.
- *
- * MPTCP_EVENT_LISTENER_CREATED: family, sport, saddr4 | saddr6
- * A new PM listener is created.
- *
- * MPTCP_EVENT_LISTENER_CLOSED: family, sport, saddr4 | saddr6
- * A PM listener is closed.
- */
-enum mptcp_event_type {
-	MPTCP_EVENT_UNSPEC = 0,
-	MPTCP_EVENT_CREATED = 1,
-	MPTCP_EVENT_ESTABLISHED = 2,
-	MPTCP_EVENT_CLOSED = 3,
-
-	MPTCP_EVENT_ANNOUNCED = 6,
-	MPTCP_EVENT_REMOVED = 7,
-
-	MPTCP_EVENT_SUB_ESTABLISHED = 10,
-	MPTCP_EVENT_SUB_CLOSED = 11,
-
-	MPTCP_EVENT_SUB_PRIORITY = 13,
-
-	MPTCP_EVENT_LISTENER_CREATED = 15,
-	MPTCP_EVENT_LISTENER_CLOSED = 16,
-};
-
-enum mptcp_event_attr {
-	MPTCP_ATTR_UNSPEC = 0,
-
-	MPTCP_ATTR_TOKEN,	/* u32 */
-	MPTCP_ATTR_FAMILY,	/* u16 */
-	MPTCP_ATTR_LOC_ID,	/* u8 */
-	MPTCP_ATTR_REM_ID,	/* u8 */
-	MPTCP_ATTR_SADDR4,	/* be32 */
-	MPTCP_ATTR_SADDR6,	/* struct in6_addr */
-	MPTCP_ATTR_DADDR4,	/* be32 */
-	MPTCP_ATTR_DADDR6,	/* struct in6_addr */
-	MPTCP_ATTR_SPORT,	/* be16 */
-	MPTCP_ATTR_DPORT,	/* be16 */
-	MPTCP_ATTR_BACKUP,	/* u8 */
-	MPTCP_ATTR_ERROR,	/* u8 */
-	MPTCP_ATTR_FLAGS,	/* u16 */
-	MPTCP_ATTR_TIMEOUT,	/* u32 */
-	MPTCP_ATTR_IF_IDX,	/* s32 */
-	MPTCP_ATTR_RESET_REASON,/* u32 */
-	MPTCP_ATTR_RESET_FLAGS, /* u32 */
-	MPTCP_ATTR_SERVER_SIDE,	/* u8 */
-
-	__MPTCP_ATTR_AFTER_LAST
-};
-
-#define MPTCP_ATTR_MAX (__MPTCP_ATTR_AFTER_LAST - 1)
-
 /* MPTCP Reset reason codes, rfc8684 */
 #define MPTCP_RST_EUNSPEC	0
 #define MPTCP_RST_EMPTCP	1
diff --git a/include/uapi/linux/mptcp_pm.h b/include/uapi/linux/mptcp_pm.h
new file mode 100644
index 000000000000..0ad598fe940b
--- /dev/null
+++ b/include/uapi/linux/mptcp_pm.h
@@ -0,0 +1,150 @@
+/* SPDX-License-Identifier: ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) */
+/* Do not edit directly, auto-generated from: */
+/*	Documentation/netlink/specs/mptcp.yaml */
+/* YNL-GEN uapi header */
+
+#ifndef _UAPI_LINUX_MPTCP_PM_H
+#define _UAPI_LINUX_MPTCP_PM_H
+
+#define MPTCP_PM_NAME	"mptcp_pm"
+#define MPTCP_PM_VER	1
+
+/**
+ * enum mptcp_event_type
+ * @MPTCP_EVENT_UNSPEC: unused event
+ * @MPTCP_EVENT_CREATED: token, family, saddr4 | saddr6, daddr4 | daddr6,
+ *   sport, dport A new MPTCP connection has been created. It is the good time
+ *   to allocate memory and send ADD_ADDR if needed. Depending on the
+ *   traffic-patterns it can take a long time until the MPTCP_EVENT_ESTABLISHED
+ *   is sent.
+ * @MPTCP_EVENT_ESTABLISHED: token, family, saddr4 | saddr6, daddr4 | daddr6,
+ *   sport, dport A MPTCP connection is established (can start new subflows).
+ * @MPTCP_EVENT_CLOSED: token A MPTCP connection has stopped.
+ * @MPTCP_EVENT_ANNOUNCED: token, rem_id, family, daddr4 | daddr6 [, dport] A
+ *   new address has been announced by the peer.
+ * @MPTCP_EVENT_REMOVED: token, rem_id An address has been lost by the peer.
+ * @MPTCP_EVENT_SUB_ESTABLISHED: token, family, loc_id, rem_id, saddr4 |
+ *   saddr6, daddr4 | daddr6, sport, dport, backup, if_idx [, error] A new
+ *   subflow has been established. 'error' should not be set.
+ * @MPTCP_EVENT_SUB_CLOSED: token, family, loc_id, rem_id, saddr4 | saddr6,
+ *   daddr4 | daddr6, sport, dport, backup, if_idx [, error] A subflow has been
+ *   closed. An error (copy of sk_err) could be set if an error has been
+ *   detected for this subflow.
+ * @MPTCP_EVENT_SUB_PRIORITY: token, family, loc_id, rem_id, saddr4 | saddr6,
+ *   daddr4 | daddr6, sport, dport, backup, if_idx [, error] The priority of a
+ *   subflow has changed. 'error' should not be set.
+ * @MPTCP_EVENT_LISTENER_CREATED: family, sport, saddr4 | saddr6 A new PM
+ *   listener is created.
+ * @MPTCP_EVENT_LISTENER_CLOSED: family, sport, saddr4 | saddr6 A PM listener
+ *   is closed.
+ */
+enum mptcp_event_type {
+	MPTCP_EVENT_UNSPEC,
+	MPTCP_EVENT_CREATED,
+	MPTCP_EVENT_ESTABLISHED,
+	MPTCP_EVENT_CLOSED,
+	MPTCP_EVENT_ANNOUNCED = 6,
+	MPTCP_EVENT_REMOVED,
+	MPTCP_EVENT_SUB_ESTABLISHED = 10,
+	MPTCP_EVENT_SUB_CLOSED,
+	MPTCP_EVENT_SUB_PRIORITY = 13,
+	MPTCP_EVENT_LISTENER_CREATED = 15,
+	MPTCP_EVENT_LISTENER_CLOSED,
+};
+
+enum {
+	MPTCP_PM_ADDR_ATTR_UNSPEC,
+	MPTCP_PM_ADDR_ATTR_FAMILY,
+	MPTCP_PM_ADDR_ATTR_ID,
+	MPTCP_PM_ADDR_ATTR_ADDR4,
+	MPTCP_PM_ADDR_ATTR_ADDR6,
+	MPTCP_PM_ADDR_ATTR_PORT,
+	MPTCP_PM_ADDR_ATTR_FLAGS,
+	MPTCP_PM_ADDR_ATTR_IF_IDX,
+
+	__MPTCP_PM_ADDR_ATTR_MAX
+};
+#define MPTCP_PM_ADDR_ATTR_MAX (__MPTCP_PM_ADDR_ATTR_MAX - 1)
+
+enum {
+	MPTCP_SUBFLOW_ATTR_UNSPEC,
+	MPTCP_SUBFLOW_ATTR_TOKEN_REM,
+	MPTCP_SUBFLOW_ATTR_TOKEN_LOC,
+	MPTCP_SUBFLOW_ATTR_RELWRITE_SEQ,
+	MPTCP_SUBFLOW_ATTR_MAP_SEQ,
+	MPTCP_SUBFLOW_ATTR_MAP_SFSEQ,
+	MPTCP_SUBFLOW_ATTR_SSN_OFFSET,
+	MPTCP_SUBFLOW_ATTR_MAP_DATALEN,
+	MPTCP_SUBFLOW_ATTR_FLAGS,
+	MPTCP_SUBFLOW_ATTR_ID_REM,
+	MPTCP_SUBFLOW_ATTR_ID_LOC,
+	MPTCP_SUBFLOW_ATTR_PAD,
+
+	__MPTCP_SUBFLOW_ATTR_MAX
+};
+#define MPTCP_SUBFLOW_ATTR_MAX (__MPTCP_SUBFLOW_ATTR_MAX - 1)
+
+enum {
+	MPTCP_PM_ENDPOINT_ADDR = 1,
+
+	__MPTCP_PM_ENDPOINT_MAX
+};
+#define MPTCP_PM_ENDPOINT_MAX (__MPTCP_PM_ENDPOINT_MAX - 1)
+
+enum {
+	MPTCP_PM_ATTR_UNSPEC,
+	MPTCP_PM_ATTR_ADDR,
+	MPTCP_PM_ATTR_RCV_ADD_ADDRS,
+	MPTCP_PM_ATTR_SUBFLOWS,
+	MPTCP_PM_ATTR_TOKEN,
+	MPTCP_PM_ATTR_LOC_ID,
+	MPTCP_PM_ATTR_ADDR_REMOTE,
+
+	__MPTCP_PM_ATTR_MAX
+};
+#define MPTCP_PM_ATTR_MAX (__MPTCP_PM_ATTR_MAX - 1)
+
+enum mptcp_event_attr {
+	MPTCP_ATTR_UNSPEC,
+	MPTCP_ATTR_TOKEN,
+	MPTCP_ATTR_FAMILY,
+	MPTCP_ATTR_LOC_ID,
+	MPTCP_ATTR_REM_ID,
+	MPTCP_ATTR_SADDR4,
+	MPTCP_ATTR_SADDR6,
+	MPTCP_ATTR_DADDR4,
+	MPTCP_ATTR_DADDR6,
+	MPTCP_ATTR_SPORT,
+	MPTCP_ATTR_DPORT,
+	MPTCP_ATTR_BACKUP,
+	MPTCP_ATTR_ERROR,
+	MPTCP_ATTR_FLAGS,
+	MPTCP_ATTR_TIMEOUT,
+	MPTCP_ATTR_IF_IDX,
+	MPTCP_ATTR_RESET_REASON,
+	MPTCP_ATTR_RESET_FLAGS,
+	MPTCP_ATTR_SERVER_SIDE,
+
+	__MPTCP_ATTR_MAX
+};
+#define MPTCP_ATTR_MAX (__MPTCP_ATTR_MAX - 1)
+
+enum {
+	MPTCP_PM_CMD_UNSPEC,
+	MPTCP_PM_CMD_ADD_ADDR,
+	MPTCP_PM_CMD_DEL_ADDR,
+	MPTCP_PM_CMD_GET_ADDR,
+	MPTCP_PM_CMD_FLUSH_ADDRS,
+	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_MAX
+};
+#define MPTCP_PM_CMD_MAX (__MPTCP_PM_CMD_MAX - 1)
+
+#endif /* _UAPI_LINUX_MPTCP_PM_H */