#endif
#define KDBUS_IOC_MAGIC 0x95
+#define KDBUS_SRC_ID_KERNEL (0)
+#define KDBUS_DST_ID_NAME (0)
+#define KDBUS_MATCH_ID_ANY (~0ULL)
+#define KDBUS_DST_ID_BROADCAST (~0ULL)
-/* Message sent from kernel to userspace, when the owner or starter of
- * a well-known name changes */
-struct kdbus_manager_msg_name_change {
- __u64 old_id;
- __u64 new_id;
- __u64 flags; /* 0 or (possibly?) KDBUS_NAME_IN_QUEUE */
- char name[0];
+/**
+ * struct kdbus_notify_id_change - name registry change message
+ * @id: New or former owner of the name
+ * @flags: flags field from KDBUS_HELLO_*
+ *
+ * Sent from kernel to userspace when the owner or activator of
+ * a well-known name changes.
+ *
+ * Attached to:
+ * KDBUS_ITEM_ID_ADD
+ * KDBUS_ITEM_ID_REMOVE
+ */
+struct kdbus_notify_id_change {
+ __u64 id;
+ __u64 flags;
};
-struct kdbus_manager_msg_id_change {
- __u64 id;
- __u64 flags; /* The kernel flags field from KDBUS_HELLO */
+/**
+ * struct kdbus_notify_name_change - name registry change message
+ * @old: ID and flags of former owner of a name
+ * @new: ID and flags of new owner of a name
+ * @name: Well-known name
+ *
+ * Sent from kernel to userspace when the owner or activator of
+ * a well-known name changes.
+ *
+ * Attached to:
+ * KDBUS_ITEM_NAME_ADD
+ * KDBUS_ITEM_NAME_REMOVE
+ * KDBUS_ITEM_NAME_CHANGE
+ */
+struct kdbus_notify_name_change {
+ struct kdbus_notify_id_change old;
+ struct kdbus_notify_id_change new;
+ char name[0];
};
+/**
+ * struct kdbus_creds - process credentials
+ * @uid: User ID
+ * @gid: Group ID
+ * @pid: Process ID
+ * @tid: Thread ID
+ * @starttime: Starttime of the process
+ *
+ * The starttime of the process PID. This is useful to detect PID overruns
+ * from the client side. i.e. if you use the PID to look something up in
+ * /proc/$PID/ you can afterwards check the starttime field of it, to ensure
+ * you didn't run into a PID overrun.
+ *
+ * Attached to:
+ * KDBUS_ITEM_CREDS
+ */
struct kdbus_creds {
__u64 uid;
__u64 gid;
__u64 pid;
__u64 tid;
-
- /* The starttime of the process PID. This is useful to detect
- PID overruns from the client side. i.e. if you use the PID to
- look something up in /proc/$PID/ you can afterwards check the
- starttime field of it to ensure you didn't run into a PID
- ovretun. */
__u64 starttime;
};
+/**
+ * struct kdbus_audit - audit information
+ * @sessionid: The audit session ID
+ * @loginuid: The audit login uid
+ *
+ * Attached to:
+ * KDBUS_ITEM_AUDIT
+ */
struct kdbus_audit {
__u64 sessionid;
__u64 loginuid;
};
+/**
+ * struct kdbus_timestamp
+ * @monotonic_ns: Monotonic timestamp, in nanoseconds
+ * @realtime_ns: Realtime timestamp, in nanoseconds
+ *
+ * Attached to:
+ * KDBUS_ITEM_TIMESTAMP
+ */
struct kdbus_timestamp {
__u64 monotonic_ns;
__u64 realtime_ns;
};
-#define KDBUS_SRC_ID_KERNEL (0)
-#define KDBUS_DST_ID_WELL_KNOWN_NAME (0)
-#define KDBUS_MATCH_SRC_ID_ANY (~0ULL)
-#define KDBUS_DST_ID_BROADCAST (~0ULL)
-
-/* Message Item Types */
-enum {
- KDBUS_MSG_NULL,
-
- /* Filled in by userspace */
- KDBUS_MSG_PAYLOAD_VEC, /* .data_vec, reference to memory area */
- KDBUS_MSG_PAYLOAD_MEMFD, /* file descriptor of a special data file */
- KDBUS_MSG_FDS, /* .data_fds of file descriptors */
- KDBUS_MSG_BLOOM, /* for broadcasts, carries bloom filter blob in .data */
- KDBUS_MSG_DST_NAME, /* destination's well-known name, in .str */
- KDBUS_MSG_PRIORITY, /* queue priority for message */
-
- /* Filled in by kernelspace */
- KDBUS_MSG_SRC_NAMES = 0x400,/* NUL separated string list with well-known names of source */
- KDBUS_MSG_TIMESTAMP, /* .timestamp */
- KDBUS_MSG_SRC_CREDS, /* .creds */
- KDBUS_MSG_SRC_PID_COMM, /* optional, in .str */
- KDBUS_MSG_SRC_TID_COMM, /* optional, in .str */
- KDBUS_MSG_SRC_EXE, /* optional, in .str */
- KDBUS_MSG_SRC_CMDLINE, /* optional, in .str (a chain of NUL str) */
- KDBUS_MSG_SRC_CGROUP, /* optional, in .str */
- KDBUS_MSG_SRC_CAPS, /* caps data blob, in .data */
- KDBUS_MSG_SRC_SECLABEL, /* NUL terminated string, in .str */
- KDBUS_MSG_SRC_AUDIT, /* .audit */
-
- /* Special messages from kernel, consisting of one and only one of these data blocks */
- KDBUS_MSG_NAME_ADD = 0x800,/* .name_change */
- KDBUS_MSG_NAME_REMOVE, /* .name_change */
- KDBUS_MSG_NAME_CHANGE, /* .name_change */
- KDBUS_MSG_ID_ADD, /* .id_change */
- KDBUS_MSG_ID_REMOVE, /* .id_change */
- KDBUS_MSG_REPLY_TIMEOUT, /* empty, but .reply_cookie in .kdbus_msg is filled in */
- KDBUS_MSG_REPLY_DEAD, /* dito */
-};
-
+/**
+ * struct kdbus_vec - I/O vector for kdbus payload items
+ * @size: The size of the vector
+ * @address: Memory address for memory addresses
+ * @offset: Offset in the in-message payload memory,
+ * relative to the message head
+ *
+ * Attached to:
+ * KDBUS_ITEM_PAYLOAD_VEC
+ */
struct kdbus_vec {
- __u64 address;
__u64 size;
+ union {
+ __u64 address;
+ __u64 offset;
+ };
};
+/**
+ * struct kdbus_memfd - a kdbus memfd
+ * @size: The memfd's size
+ * @fd: The file descriptor number
+ * @__pad: Padding to make the struct aligned
+ *
+ * Attached to:
+ * KDBUS_ITEM_PAYLOAD_MEMFD
+ */
struct kdbus_memfd {
__u64 size;
int fd;
+ __u32 __pad;
+};
+
+/**
+ * struct kdbus_name - a registered well-known name with its flags
+ * @flags: flags from KDBUS_NAME_*
+ * @name: well-known name
+ *
+ * Attached to:
+ * KDBUS_ITEM_NAME
+ */
+struct kdbus_name {
+ __u64 flags;
+ char name[0];
};
/**
- * struct kdbus_item - chain of data blocks
+ * struct kdbus_policy_access - policy access item
+ * @type: One of KDBUS_POLICY_ACCESS_* types
+ * @bits: Access to grant. One of KDBUS_POLICY_*
+ * @id: For KDBUS_POLICY_ACCESS_USER, the uid
+ * For KDBUS_POLICY_ACCESS_GROUP, the gid
*
- * size: overall data record size
- * type: kdbus_item type of data
+ * Embedded in:
+ * struct kdbus_policy
+ */
+struct kdbus_policy_access {
+ __u64 type; /* USER, GROUP, WORLD */
+ __u64 bits; /* RECV, SEND, OWN */
+ __u64 id; /* uid, gid, 0 */
+};
+
+/**
+ * struct kdbus_policy - a policy item
+ * @access: Policy access details
+ * @name: Well-known name to grant access to
+ *
+ * Attached to:
+ * KDBUS_POLICY_ACCESS
+ * KDBUS_ITEM_POLICY_NAME
+ */
+struct kdbus_policy {
+ union {
+ struct kdbus_policy_access access;
+ char name[0];
+ };
+};
+
+/**
+ * enum kdbus_item_type - item types to chain data in a list
+ * @KDBUS_ITEM_PAYLOAD_VEC: Vector to data
+ * @KDBUS_ITEM_PAYLOAD_OFF: Data at returned offset to message head
+ * @KDBUS_ITEM_PAYLOAD_MEMFD: Data as sealed memfd
+ * @KDBUS_ITEM_FDS: Attached file descriptors
+ * @KDBUS_ITEM_BLOOM: For broadcasts, carries bloom filter
+ * @KDBUS_ITEM_BLOOM_SIZE: Desired bloom size, used by KDBUS_CMD_BUS_MAKE
+ * @KDBUS_ITEM_DST_NAME: Destination's well-known name
+ * @KDBUS_ITEM_PRIORITY: Queue priority for message
+ * @KDBUS_ITEM_MAKE_NAME: Name of namespace, bus, endpoint
+ * @KDBUS_ITEM_POLICY_NAME: Policy in struct kdbus_policy
+ * @KDBUS_ITEM_POLICY_ACCESS: Policy in struct kdbus_policy
+ * @KDBUS_ITEM_NAME: Well-know name with flags
+ * @KDBUS_ITEM_ID: Connection ID
+ * @KDBUS_ITEM_TIMESTAMP: Timestamp
+ * @KDBUS_ITEM_CREDS: Process credential
+ * @KDBUS_ITEM_PID_COMM: Process ID "comm" identifier
+ * @KDBUS_ITEM_TID_COMM: Thread ID "comm" identifier
+ * @KDBUS_ITEM_EXE: The path of the executable
+ * @KDBUS_ITEM_CMDLINE: The process command line
+ * @KDBUS_ITEM_CGROUP: The croup membership
+ * @KDBUS_ITEM_CAPS: The process capabilities
+ * @KDBUS_ITEM_SECLABEL: The security label
+ * @KDBUS_ITEM_AUDIT: The audit IDs
+ * @KDBUS_ITEM_NAME_ADD: Notify in struct kdbus_notify_name_change
+ * @KDBUS_ITEM_NAME_REMOVE: Notify in struct kdbus_notify_name_change
+ * @KDBUS_ITEM_NAME_CHANGE: Notify in struct kdbus_notify_name_change
+ * @KDBUS_ITEM_ID_ADD: Notify in struct kdbus_notify_id_change
+ * @KDBUS_ITEM_ID_REMOVE: Notify in struct kdbus_notify_id_change
+ * @KDBUS_ITEM_REPLY_TIMEOUT: Timeout has been reached
+ * @KDBUS_ITEM_REPLY_DEAD: Destination died
+ */
+enum kdbus_item_type {
+ _KDBUS_ITEM_NULL,
+ _KDBUS_ITEM_USER_BASE,
+ KDBUS_ITEM_PAYLOAD_VEC = _KDBUS_ITEM_USER_BASE,
+ KDBUS_ITEM_PAYLOAD_OFF,
+ KDBUS_ITEM_PAYLOAD_MEMFD,
+ KDBUS_ITEM_FDS,
+ KDBUS_ITEM_BLOOM,
+ KDBUS_ITEM_BLOOM_SIZE,
+ KDBUS_ITEM_DST_NAME,
+ KDBUS_ITEM_PRIORITY,
+ KDBUS_ITEM_MAKE_NAME,
+
+ _KDBUS_ITEM_POLICY_BASE = 0x400,
+ KDBUS_ITEM_POLICY_NAME = _KDBUS_ITEM_POLICY_BASE,
+ KDBUS_ITEM_POLICY_ACCESS,
+
+ _KDBUS_ITEM_ATTACH_BASE = 0x600,
+ KDBUS_ITEM_NAME = _KDBUS_ITEM_ATTACH_BASE,
+ KDBUS_ITEM_ID,
+ KDBUS_ITEM_TIMESTAMP,
+ KDBUS_ITEM_CREDS,
+ KDBUS_ITEM_PID_COMM,
+ KDBUS_ITEM_TID_COMM,
+ KDBUS_ITEM_EXE,
+ KDBUS_ITEM_CMDLINE,
+ KDBUS_ITEM_CGROUP,
+ KDBUS_ITEM_CAPS,
+ KDBUS_ITEM_SECLABEL,
+ KDBUS_ITEM_AUDIT,
+
+ _KDBUS_ITEM_KERNEL_BASE = 0x800,
+ KDBUS_ITEM_NAME_ADD = _KDBUS_ITEM_KERNEL_BASE,
+ KDBUS_ITEM_NAME_REMOVE,
+ KDBUS_ITEM_NAME_CHANGE,
+ KDBUS_ITEM_ID_ADD,
+ KDBUS_ITEM_ID_REMOVE,
+ KDBUS_ITEM_REPLY_TIMEOUT,
+ KDBUS_ITEM_REPLY_DEAD,
+};
+
+/**
+ * struct kdbus_item - chain of data blocks
+ * @size: Overall data record size
+ * @type: Kdbus_item type of data
+ * @data: Generic bytes
+ * @data32: Generic 32 bit array
+ * @data64: Generic 64 bit array
+ * @str: Generic string
+ * @id: Connection ID
+ * @vec: KDBUS_ITEM_PAYLOAD_VEC
+ * @creds: KDBUS_ITEM_CREDS
+ * @audit: KDBUS_ITEM_AUDIT
+ * @timestamp: KDBUS_ITEM_TIMESTAMP
+ * @name: KDBUS_ITEM_NAME
+ * @memfd: KDBUS_ITEM_PAYLOAD_MEMFD
+ * @name_change: KDBUS_ITEM_NAME_ADD
+ * KDBUS_ITEM_NAME_REMOVE
+ * KDBUS_ITEM_NAME_CHANGE
+ * @id_change: KDBUS_ITEM_ID_ADD
+ * KDBUS_ITEM_ID_REMOVE
+ * @policy: KDBUS_ITEM_POLICY_NAME
+ * KDBUS_ITEM_POLICY_ACCESS
*/
struct kdbus_item {
__u64 size;
__u64 type;
union {
- /* inline data */
__u8 data[0];
__u32 data32[0];
__u64 data64[0];
char str[0];
- /* connection */
__u64 id;
-
- /* data vector */
struct kdbus_vec vec;
-
- /* process credentials and properties*/
struct kdbus_creds creds;
struct kdbus_audit audit;
struct kdbus_timestamp timestamp;
-
- /* specific fields */
+ struct kdbus_name name;
+ struct kdbus_memfd memfd;
int fds[0];
- struct kdbus_manager_msg_name_change name_change;
- struct kdbus_manager_msg_id_change id_change;
+ struct kdbus_notify_name_change name_change;
+ struct kdbus_notify_id_change id_change;
+ struct kdbus_policy policy;
};
};
-enum {
+/**
+ * enum kdbus_msg_flags - type of message
+ * @KDBUS_MSG_FLAGS_EXPECT_REPLY: Expect a reply message, used for method
+ * calls. The cookie identifies the
+ * message and the respective reply
+ * @KDBUS_MSG_FLAGS_NO_AUTO_START: Do not start a service, if the addressed
+ * name is not currently active
+ */
+enum kdbus_msg_flags {
KDBUS_MSG_FLAGS_EXPECT_REPLY = 1 << 0,
KDBUS_MSG_FLAGS_NO_AUTO_START = 1 << 1,
};
-enum {
- KDBUS_PAYLOAD_NULL,
- KDBUS_PAYLOAD_DBUS1 = 0x4442757356657231ULL, /* 'DBusVer1' */
- KDBUS_PAYLOAD_GVARIANT = 0x4756617269616e74ULL, /* 'GVariant' */
+/**
+ * enum kdbus_payload_type - type of payload carried by message
+ * @KDBUS_PAYLOAD_KERNEL: Kernel-generated simple message
+ * @KDBUS_PAYLOAD_DBUS: D-Bus marshalling
+ */
+enum kdbus_payload_type {
+ KDBUS_PAYLOAD_KERNEL,
+ KDBUS_PAYLOAD_DBUS = 0x4442757344427573ULL, /* 'DBusDBus' */
};
/**
- * struct kdbus_msg
- *
- * set by userspace:
- * dst_id: destination id
- * flags: KDBUS_MSG_FLAGS_*
- * items: data records
- *
- * set by kernel:
- * src_id: who sent the message
+ * struct kdbus_msg - the representation of a kdbus message
+ * @size: Total size of the message
+ * @flags: Message flags (KDBUS_MSG_FLAGS_*)
+ * @dst_id: 64-bit ID of the destination connection
+ * @src_id: 64-bit ID of the source connection
+ * @payload_type: Payload type (KDBUS_PAYLOAD_*)
+ * @cookie: Userspace-supplied cookie
+ * @cookie_reply: For kernel-generated messages, this is the cookie
+ * the message is a reply to
+ * @timeout_ns: For non-kernel-generated messages, this denotes the
+ * message timeout in nanoseconds. A message has to be
+ * received with KDBUS_CMD_MSG_RECV by the destination
+ * connection within this time frame. For messages that
+ * have KDBUS_MSG_FLAGS_EXPECT_REPLY set in @flags,
+ * this value also denotes the timeout for the reply to
+ * this message. If there is no reply, or the message is
+ * not received in time by the other side, a
+ * kernel-generated message with an attached
+ * KDBUS_ITEM_REPLY_TIMEOUT item is sent to @src_id.
+ * A 0-value is only valid if KDBUS_MSG_FLAGS_EXPECT_REPLY
+ * is unset in @flags.
+ * @items: A list of kdbus_items containing the message payload
*/
struct kdbus_msg {
__u64 size;
__u64 flags;
- __u64 dst_id; /* connection, 0 == name in data, ~0 broadcast */
- __u64 src_id; /* connection, 0 == kernel */
- __u64 payload_type; /* 'DBusVer1', 'GVariant', ... */
- __u64 cookie; /* userspace-supplied cookie */
+ __u64 dst_id;
+ __u64 src_id;
+ __u64 payload_type;
+ __u64 cookie;
union {
- __u64 cookie_reply; /* cookie we reply to */
- __u64 timeout_ns; /* timespan to wait for reply */
+ __u64 cookie_reply;
+ __u64 timeout_ns;
};
struct kdbus_item items[0];
-};
-
-enum {
- KDBUS_POLICY_NULL,
- KDBUS_POLICY_NAME,
- KDBUS_POLICY_ACCESS,
-};
+} __attribute__((aligned(8)));
-enum {
- KDBUS_POLICY_ACCESS_NULL,
+/**
+ * enum kdbus_policy_access_type - permissions of a policy record
+ * @KDBUS_POLICY_ACCESS_USER: Grant access to a uid
+ * @KDBUS_POLICY_ACCESS_GROUP: Grant access to gid
+ * @KDBUS_POLICY_ACCESS_WORLD: World-accessible
+ */
+enum kdbus_policy_access_type {
+ _KDBUS_POLICY_ACCESS_NULL,
KDBUS_POLICY_ACCESS_USER,
KDBUS_POLICY_ACCESS_GROUP,
KDBUS_POLICY_ACCESS_WORLD,
};
-enum {
+/**
+ * enum kdbus_policy_access_flags - mode flags
+ * @KDBUS_POLICY_RECV: Allow receive
+ * @KDBUS_POLICY_SEND: Allow send
+ * @KDBUS_POLICY_OWN: Allow to own a well-known name
+ */
+enum kdbus_policy_type {
KDBUS_POLICY_RECV = 1 << 2,
KDBUS_POLICY_SEND = 1 << 1,
KDBUS_POLICY_OWN = 1 << 0,
};
-struct kdbus_policy {
- __u64 size;
- __u64 type; /* NAME or ACCESS */
- union {
- char name[0];
- struct {
- __u32 type; /* USER, GROUP, WORLD */
- __u32 bits; /* RECV, SEND, OWN */
- __u64 id; /* uid, gid, 0 */
- } access;
- };
-};
-
+/**
+ * struct kdbus_cmd_policy - a series of policies to upload
+ * @size: The total size of the structure
+ * @policies: The policies to upload
+ *
+ * A KDBUS_POLICY_NAME must always preceeds a KDBUS_POLICY_ACCESS entry.
+ * A new KDBUS_POLICY_NAME can be added after KDBUS_POLICY_ACCESS for
+ * chaining multiple policies together.
+ */
struct kdbus_cmd_policy {
__u64 size;
- __u8 buffer[0]; /* a series of KDBUS_POLICY_NAME plus one or
- * more KDBUS_POLICY_ACCESS each. */
-};
+ struct kdbus_item policies[0];
+} __attribute__((aligned(8)));
-/* Flags for struct kdbus_cmd_hello */
-enum {
- KDBUS_HELLO_STARTER = 1 << 0,
- KDBUS_HELLO_ACCEPT_FD = 1 << 1,
-
- /* The following have an effect on directed messages only --
- * not for broadcasts */
- KDBUS_HELLO_ATTACH_COMM = 1 << 10,
- KDBUS_HELLO_ATTACH_EXE = 1 << 11,
- KDBUS_HELLO_ATTACH_CMDLINE = 1 << 12,
- KDBUS_HELLO_ATTACH_CGROUP = 1 << 13,
- KDBUS_HELLO_ATTACH_CAPS = 1 << 14,
- KDBUS_HELLO_ATTACH_SECLABEL = 1 << 15,
- KDBUS_HELLO_ATTACH_AUDIT = 1 << 16,
+/**
+ * enum kdbus_hello_flags - flags for struct kdbus_cmd_hello
+ * @KDBUS_HELLO_ACCEPT_FD: The connection allows the receiving of
+ * any passed file descriptors
+ * @KDBUS_HELLO_ACTIVATOR: Special-purpose connection which registers
+ * a well-know name for a process to be started
+ * when traffic arrives
+ * @KDBUS_HELLO_MONITOR: Special-purpose connection to monitor
+ * bus traffic
+ */
+enum kdbus_hello_flags {
+ KDBUS_HELLO_ACCEPT_FD = 1 << 0,
+ KDBUS_HELLO_ACTIVATOR = 1 << 1,
+ KDBUS_HELLO_MONITOR = 1 << 2,
};
-/* Items to append to struct kdbus_cmd_hello */
-enum {
- KDBUS_HELLO_NULL,
- KDBUS_HELLO_POOL, /* kdbus_vec, userspace supplied buffer to
- * place received messages */
+/**
+ * enum kdbus_attach_flags - flags for metadata attachments
+ * @KDBUS_ATTACH_TIMESTAMP: Timestamp
+ * @KDBUS_ATTACH_CREDS: Credentials
+ * @KDBUS_ATTACH_NAMES: Well-known names
+ * @KDBUS_ATTACH_COMM: The "comm" process identifier
+ * @KDBUS_ATTACH_EXE: The path of the executable
+ * @KDBUS_ATTACH_CMDLINE: The process command line
+ * @KDBUS_ATTACH_CGROUP: The croup membership
+ * @KDBUS_ATTACH_CAPS: The process capabilities
+ * @KDBUS_ATTACH_SECLABEL: The security label
+ * @KDBUS_ATTACH_AUDIT: The audit IDs
+ */
+enum kdbus_attach_flags {
+ KDBUS_ATTACH_TIMESTAMP = 1 << 0,
+ KDBUS_ATTACH_CREDS = 1 << 1,
+ KDBUS_ATTACH_NAMES = 1 << 2,
+ KDBUS_ATTACH_COMM = 1 << 3,
+ KDBUS_ATTACH_EXE = 1 << 4,
+ KDBUS_ATTACH_CMDLINE = 1 << 5,
+ KDBUS_ATTACH_CGROUP = 1 << 6,
+ KDBUS_ATTACH_CAPS = 1 << 7,
+ KDBUS_ATTACH_SECLABEL = 1 << 8,
+ KDBUS_ATTACH_AUDIT = 1 << 9,
};
+/**
+ * struct kdbus_cmd_hello - struct to say hello to kdbus
+ * @size: The total size of the structure
+ * @conn_flags: Connection flags (KDBUS_HELLO_*). The kernel will
+ * return its capabilities in that field.
+ * @attach_flags: Mask of metadata to attach to each message sent
+ * (KDBUS_ATTACH_*)
+ * @bus_flags: The flags field copied verbatim from the original
+ * KDBUS_CMD_BUS_MAKE ioctl. It's intended to be useful
+ * to do negotiation of features of the payload that is
+ * transferred (kernel → userspace)
+ * @id: The ID of this connection (kernel → userspace)
+ * @bloom_size: The bloom filter size chosen by the owner
+ * (kernel → userspace)
+ * @pool_size: Maximum size of the pool buffer (kernel → userspace)
+ * @id128: Unique 128-bit ID of the bus (kernel → userspace)
+ * @items: A list of items
+ *
+ * This struct is used with the KDBUS_CMD_HELLO ioctl. See the ioctl
+ * documentation for more information.
+ */
struct kdbus_cmd_hello {
__u64 size;
-
- /* userspace → kernel, kernel → userspace */
- __u64 conn_flags; /* userspace specifies its
- * capabilities and more, kernel
- * returns its capabilites and
- * more. Kernel might refuse client's
- * capabilities by returning an error
- * from KDBUS_HELLO */
-
- /* kernel → userspace */
- __u64 bus_flags; /* this is .flags copied verbatim from
- * from original KDBUS_CMD_BUS_MAKE
- * ioctl. It's intended to be useful
- * to do negotiation of features of
- * the payload that is transfreted. */
- __u64 id; /* id assigned to this connection */
- __u64 bloom_size; /* The bloom filter size chosen by the
- * bus owner */
+ __u64 conn_flags;
+ __u64 attach_flags;
+ __u64 bus_flags;
+ __u64 id;
+ __u64 bloom_size;
+ __u64 pool_size;
+ __u8 id128[16];
struct kdbus_item items[0];
-};
+} __attribute__((aligned(8)));
-/* Flags for kdbus_cmd_{bus,ep,ns}_make */
-enum {
+/* Flags for KDBUS_CMD_{BUS,EP,NS}_MAKE */
+enum kdbus_make_flags {
KDBUS_MAKE_ACCESS_GROUP = 1 << 0,
KDBUS_MAKE_ACCESS_WORLD = 1 << 1,
KDBUS_MAKE_POLICY_OPEN = 1 << 2,
};
-/* Items to append to kdbus_cmd_{bus,ep,ns}_make */
-enum {
- KDBUS_MAKE_NULL,
- KDBUS_MAKE_NAME,
- KDBUS_MAKE_CGROUP, /* the cgroup hierarchy ID for which to attach
- * cgroup membership paths * to messages. */
- KDBUS_MAKE_CRED, /* allow translator services which connect
- * to the bus on behalf of somebody else,
- * allow specifiying the credentials of the
- * client to connect on behalf on. Needs
- * privileges */
-};
-
-struct kdbus_cmd_bus_make {
- __u64 size;
- __u64 flags; /* userspace → kernel, kernel → userspace
- * When creating a bus feature
- * kernel negotiation. */
- __u64 bus_flags; /* userspace → kernel
- * When a bus is created this value is
- * copied verbatim into the bus
- * structure and returned from
- * KDBUS_CMD_HELLO, later */
- __u64 bloom_size; /* size of the bloom filter for this bus */
- struct kdbus_item items[0];
-
-};
-
-struct kdbus_cmd_ep_make {
- __u64 size;
- __u64 flags; /* userspace → kernel, kernel → userspace
- * When creating an entry point
- * feature kernel negotiation done the
- * same way as for
- * KDBUS_CMD_BUS_MAKE. Unused for
- * now. */
- struct kdbus_item items[0];
-};
-
-struct kdbus_cmd_ns_make {
+/**
+ * struct kdbus_cmd_make - struct to make a bus, an endpoint or a namespace
+ * @size: The total size of the struct
+ * @flags: Properties for the bus/ep/ns to create
+ * @items: Items describing details
+ *
+ * This structure is used with the KDBUS_CMD_BUS_MAKE, KDBUS_CMD_EP_MAKE and
+ * KDBUS_CMD_NS_MAKE ioctls.
+ */
+struct kdbus_cmd_make {
__u64 size;
- __u64 flags; /* userspace → kernel, kernel → userspace
- * When creating an entry point
- * feature kernel negotiation done the
- * same way as for
- * KDBUS_CMD_BUS_MAKE. Unused for
- * now. */
+ __u64 flags;
struct kdbus_item items[0];
-};
-
-enum {
- /* userspace → kernel */
- KDBUS_NAME_REPLACE_EXISTING = 1 << 0,
- KDBUS_NAME_QUEUE = 1 << 1,
- KDBUS_NAME_ALLOW_REPLACEMENT = 1 << 2,
+} __attribute__((aligned(8)));
- /* kernel → userspace */
- KDBUS_NAME_IN_QUEUE = 1 << 16,
+/**
+ * enum kdbus_name_flags - properties of a well-known name
+ * @KDBUS_NAME_REPLACE_EXISTING: Try to replace name of other connections
+ * @KDBUS_NAME_ALLOW_REPLACEMENT: Allow the replacement of the name
+ * @KDBUS_NAME_QUEUE: Name should be queued if busy
+ * @KDBUS_NAME_IN_QUEUE: Name is queued
+ * @KDBUS_NAME_ACTIVATOR: Name is owned by a activator connection
+ */
+enum kdbus_name_flags {
+ KDBUS_NAME_REPLACE_EXISTING = 1 << 0,
+ KDBUS_NAME_ALLOW_REPLACEMENT = 1 << 1,
+ KDBUS_NAME_QUEUE = 1 << 2,
+ KDBUS_NAME_IN_QUEUE = 1 << 3,
+ KDBUS_NAME_ACTIVATOR = 1 << 4,
};
+/**
+ * struct kdbus_cmd_name - struct to describe a well-known name
+ * @size: The total size of the struct
+ * @flags: Flags for a name entry (KDBUS_NAME_*)
+ * @id: Privileged users may use this field to (de)register
+ * names on behalf of other peers.
+ * @conn_flags: The flags of the owning connection (KDBUS_HELLO_*)
+ * @name: The well-known name
+ *
+ * This structure is used with the KDBUS_CMD_NAME_ACQUIRE ioctl.
+ */
struct kdbus_cmd_name {
__u64 size;
- __u64 name_flags;
- __u64 id; /* We allow registration/deregestration of names of other peers */
+ __u64 flags;
+ __u64 id;
__u64 conn_flags;
char name[0];
+} __attribute__((aligned(8)));
+
+/**
+ * enum kdbus_name_list_flags - what to include into the returned list
+ * @KDBUS_NAME_LIST_UNIQUE: All active connections
+ * @KDBUS_NAME_LIST_NAMES: All known well-known names
+ * @KDBUS_NAME_LIST_ACTIVATORS: All activator connections
+ * @KDBUS_NAME_LIST_QUEUED: All queued-up names
+ */
+enum kdbus_name_list_flags {
+ KDBUS_NAME_LIST_UNIQUE = 1 << 0,
+ KDBUS_NAME_LIST_NAMES = 1 << 1,
+ KDBUS_NAME_LIST_ACTIVATORS = 1 << 2,
+ KDBUS_NAME_LIST_QUEUED = 1 << 3,
};
-struct kdbus_cmd_names {
+/**
+ * struct kdbus_cmd_name_list - request a list of name entries
+ * @flags: Flags for the query (KDBUS_NAME_LIST_*)
+ * @offset: The returned offset in the caller's pool buffer.
+ * The user must use KDBUS_CMD_FREE to free the
+ * allocated memory.
+ *
+ * This structure is used with the KDBUS_CMD_NAME_LIST ioctl.
+ */
+struct kdbus_cmd_name_list {
+ __u64 flags;
+ __u64 offset;
+} __attribute__((aligned(8)));
+
+/**
+ * struct kdbus_name_list - information returned by KDBUS_CMD_NAME_LIST
+ * @size: The total size of the structure
+ * @names: A list of names
+ *
+ * Note that the user is responsible for freeing the allocated memory with
+ * the KDBUS_CMD_FREE ioctl.
+ */
+struct kdbus_name_list {
__u64 size;
struct kdbus_cmd_name names[0];
};
-enum {
- KDBUS_NAME_INFO_ITEM_NULL,
- KDBUS_NAME_INFO_ITEM_NAME, /* userspace → kernel */
- KDBUS_NAME_INFO_ITEM_SECLABEL, /* kernel → userspace */
- KDBUS_NAME_INFO_ITEM_AUDIT, /* kernel → userspace */
-};
-
-struct kdbus_cmd_name_info {
- __u64 size; /* overall size of info */
+/**
+ * struct kdbus_cmd_conn_info - struct used for KDBUS_CMD_CONN_INFO ioctl
+ * @size: The total size of the struct
+ * @flags: KDBUS_ATTACH_* flags
+ * @id: The 64-bit ID of the connection. If set to zero, passing
+ * @name is required. kdbus will look up the name to determine
+ * the ID in this case.
+ * @offset: Returned offset in the caller's pool buffer where the
+ * kdbus_conn_info struct result is stored. The user must
+ * use KDBUS_CMD_FREE to free the allocated memory.
+ * @name: The optional well-known name to look up. Only needed in
+ * case @id is zero.
+ *
+ * On success, the KDBUS_CMD_CONN_INFO ioctl will return 0 and @offset will
+ * tell the user the offset in the connection pool buffer at which to find the
+ * result in a struct kdbus_conn_info.
+ */
+struct kdbus_cmd_conn_info {
+ __u64 size;
__u64 flags;
- __u64 id; /* either ID, or 0 and _ITEM_NAME follows */
- struct kdbus_creds creds;
- struct kdbus_item items[0]; /* list of item records */
-};
+ __u64 id;
+ __u64 offset;
+ char name[0];
+} __attribute__((aligned(8)));
-enum {
- KDBUS_MATCH_NULL,
- KDBUS_MATCH_BLOOM, /* Matches a mask blob against KDBUS_MSG_BLOOM */
- KDBUS_MATCH_SRC_NAME, /* Matches a name string against KDBUS_MSG_SRC_NAMES */
- KDBUS_MATCH_NAME_ADD, /* Matches a name string against KDBUS_MSG_NAME_ADD */
- KDBUS_MATCH_NAME_REMOVE, /* Matches a name string against KDBUS_MSG_NAME_REMOVE */
- KDBUS_MATCH_NAME_CHANGE, /* Matches a name string against KDBUS_MSG_NAME_CHANGE */
- KDBUS_MATCH_ID_ADD, /* Matches an ID against KDBUS_MSG_ID_ADD */
- KDBUS_MATCH_ID_REMOVE, /* Matches an ID against KDBUS_MSG_ID_REMOVE */
+/**
+ * struct kdbus_conn_info - information returned by KDBUS_CMD_CONN_INFO
+ * @size: The total size of the struct
+ * @id: The connection's 64-bit ID
+ * @flags: The connection's flags
+ * @items: A list of struct kdbus_item
+ *
+ * Note that the user is responsible for freeing the allocated memory with
+ * the KDBUS_CMD_FREE ioctl.
+ */
+struct kdbus_conn_info {
+ __u64 size;
+ __u64 id;
+ __u64 flags;
+ struct kdbus_item items[0];
};
+/**
+ * struct kdbus_cmd_match - struct to add or remove matches
+ * @size: The total size of the struct
+ * @id: Privileged users may (de)register matches on behalf
+ * of other peers. In other cases, set to 0.
+ * @cookie: Userspace supplied cookie. When removing, the cookie
+ * identifies the match to remove.
+ * @items: A list of items for additional information
+ *
+ * This structure is used with the KDBUS_CMD_ADD_MATCH and
+ * KDBUS_CMD_REMOVE_MATCH ioctl.
+ */
struct kdbus_cmd_match {
__u64 size;
- __u64 id; /* We allow registration/deregestration of matches for other peers */
- __u64 cookie; /* userspace supplied cookie; when removing; kernel deletes everything with same cookie */
- __u64 src_id; /* ~0: any. other: exact unique match */
+ __u64 id;
+ __u64 cookie;
struct kdbus_item items[0];
-};
+} __attribute__((aligned(8)));
-struct kdbus_cmd_monitor {
- __u64 id; /* We allow setting the monitor flag of other peers */
- unsigned int enabled; /* A boolean to enable/disable monitoring */
-};
+/**
+ * enum kdbus_ioctl_type - Ioctl API
+ * @KDBUS_CMD_BUS_MAKE: After opening the "control" device node, this
+ * command creates a new bus with the specified
+ * name. The bus is immediately shut down and
+ * cleaned up when the opened "control" device node
+ * is closed.
+ * @KDBUS_CMD_NS_MAKE: Similar to KDBUS_CMD_BUS_MAKE, but it creates a
+ * new kdbus namespace.
+ * @KDBUS_CMD_EP_MAKE: Creates a new named special endpoint to talk to
+ * the bus. Such endpoints usually carry a more
+ * restrictive policy and grant restricted access
+ * to specific applications.
+ * @KDBUS_CMD_HELLO: By opening the bus device node a connection is
+ * created. After a HELLO the opened connection
+ * becomes an active peer on the bus.
+ * @KDBUS_CMD_BYEBYE: Disconnect a connection. If the connection's
+ * message list is empty, the calls succeeds, and
+ * the handle is rendered unusable. Otherwise,
+ * -EAGAIN is returned without any further side-
+ * effects.
+ * @KDBUS_CMD_MSG_SEND: Send a message and pass data from userspace to
+ * the kernel.
+ * @KDBUS_CMD_MSG_RECV: Receive a message from the kernel which is
+ * placed in the receiver's pool.
+ * @KDBUS_CMD_FREE: Release the allocated memory in the receiver's
+ * pool.
+ * @KDBUS_CMD_DROP: Drop and free the next queued message and all
+ * its ressources without actually receiveing it.
+ * @KDBUS_CMD_SRC: Return the sender's connection ID of the next
+ * queued message.
+ * @KDBUS_CMD_NAME_ACQUIRE: Request a well-known bus name to associate with
+ * the connection. Well-known names are used to
+ * address a peer on the bus.
+ * @KDBUS_CMD_NAME_RELEASE: Release a well-known name the connection
+ * currently owns.
+ * @KDBUS_CMD_NAME_LIST: Retrieve the list of all currently registered
+ * well-known and unique names.
+ * @KDBUS_CMD_CONN_INFO: Retrieve credentials and properties of the
+ * initial creator of the connection. The data was
+ * stored at registration time and does not
+ * necessarily represent the connected process or
+ * the actual state of the process.
+ * @KDBUS_CMD_MATCH_ADD: Install a match which broadcast messages should
+ * be delivered to the connection.
+ * @KDBUS_CMD_MATCH_REMOVE: Remove a current match for broadcast messages.
+ * @KDBUS_CMD_EP_POLICY_SET: Set the policy of an endpoint. It is used to
+ * restrict the access for endpoints created with
+ * KDBUS_CMD_EP_MAKE.
+ * @KDBUS_CMD_MEMFD_NEW: Return a new file descriptor which provides an
+ * anonymous shared memory file and which can be
+ * used to pass around larger chunks of data.
+ * Kdbus memfd files can be sealed, which allows
+ * the receiver to trust the data it has received.
+ * Kdbus memfd files expose only very limited
+ * operations, they can be mmap()ed, seek()ed,
+ * (p)read(v)() and (p)write(v)(); most other
+ * common file operations are not implemented.
+ * Special caution needs to be taken with
+ * read(v)()/write(v)() on a shared file; the
+ * underlying file position is always shared
+ * between all users of the file and race against
+ * each other, pread(v)()/pwrite(v)() avoid these
+ * issues.
+ * @KDBUS_CMD_MEMFD_SIZE_GET: Return the size of the underlying file, which
+ * changes with write().
+ * @KDBUS_CMD_MEMFD_SIZE_SET: Truncate the underlying file to the specified
+ * size.
+ * @KDBUS_CMD_MEMFD_SEAL_GET: Return the state of the file sealing.
+ * @KDBUS_CMD_MEMFD_SEAL_SET: Seal or break a seal of the file. Only files
+ * which are not shared with other processes and
+ * which are currently not mapped can be sealed.
+ * The current process needs to be the one and
+ * single owner of the file, the sealing cannot
+ * be changed as long as the file is shared.
+ */
+enum kdbus_ioctl_type {
+ KDBUS_CMD_BUS_MAKE = _IOW (KDBUS_IOC_MAGIC, 0x00, struct kdbus_cmd_make),
+ KDBUS_CMD_NS_MAKE = _IOR (KDBUS_IOC_MAGIC, 0x10, struct kdbus_cmd_make),
+ KDBUS_CMD_EP_MAKE = _IOW (KDBUS_IOC_MAGIC, 0x20, struct kdbus_cmd_make),
-/* FD states:
- * control nodes: unset
- * bus owner (via KDBUS_CMD_BUS_MAKE)
- * ns owner (via KDBUS_CMD_NS_MAKE)
- *
- * ep nodes: unset
- * connected (via KDBUS_CMD_HELLO)
- * starter (via KDBUS_CMD_HELLO with KDBUS_CMD_HELLO_STARTER)
- * ep owner (via KDBUS_CMD_EP_MAKE)
- */
-enum kdbus_cmd {
- /* kdbus control node commands: require unset state */
- KDBUS_CMD_BUS_MAKE = _IOWR(KDBUS_IOC_MAGIC, 0x00, struct kdbus_cmd_bus_make),
- KDBUS_CMD_NS_MAKE = _IOWR(KDBUS_IOC_MAGIC, 0x10, struct kdbus_cmd_ns_make),
-
- /* kdbus ep node commands: require unset state */
- KDBUS_CMD_EP_MAKE = _IOWR(KDBUS_IOC_MAGIC, 0x20, struct kdbus_cmd_ep_make),
KDBUS_CMD_HELLO = _IOWR(KDBUS_IOC_MAGIC, 0x30, struct kdbus_cmd_hello),
+ KDBUS_CMD_BYEBYE = _IO (KDBUS_IOC_MAGIC, 0x31),
- /* kdbus ep node commands: require connected state */
- KDBUS_CMD_MSG_SEND = _IOWR(KDBUS_IOC_MAGIC, 0x40, struct kdbus_msg),
- KDBUS_CMD_MSG_RECV = _IOWR(KDBUS_IOC_MAGIC, 0x41, struct kdbus_msg *),
- KDBUS_CMD_MSG_RELEASE = _IOWR(KDBUS_IOC_MAGIC, 0x42, struct kdbus_msg),
+ KDBUS_CMD_MSG_SEND = _IOW (KDBUS_IOC_MAGIC, 0x40, struct kdbus_msg),
+ KDBUS_CMD_MSG_RECV = _IOR (KDBUS_IOC_MAGIC, 0x41, __u64 *),
+ KDBUS_CMD_FREE = _IOW (KDBUS_IOC_MAGIC, 0x42, __u64 *),
+ KDBUS_CMD_MSG_DROP = _IO (KDBUS_IOC_MAGIC, 0x43),
+ KDBUS_CMD_MSG_SRC = _IOR (KDBUS_IOC_MAGIC, 0x44, __u64 *),
KDBUS_CMD_NAME_ACQUIRE = _IOWR(KDBUS_IOC_MAGIC, 0x50, struct kdbus_cmd_name),
- KDBUS_CMD_NAME_RELEASE = _IOWR(KDBUS_IOC_MAGIC, 0x51, struct kdbus_cmd_name),
- KDBUS_CMD_NAME_LIST = _IOWR(KDBUS_IOC_MAGIC, 0x52, struct kdbus_cmd_names),
- KDBUS_CMD_NAME_QUERY = _IOWR(KDBUS_IOC_MAGIC, 0x53, struct kdbus_cmd_name_info),
+ KDBUS_CMD_NAME_RELEASE = _IOW (KDBUS_IOC_MAGIC, 0x51, struct kdbus_cmd_name),
+ KDBUS_CMD_NAME_LIST = _IOWR(KDBUS_IOC_MAGIC, 0x52, struct kdbus_cmd_name_list),
- KDBUS_CMD_MATCH_ADD = _IOWR(KDBUS_IOC_MAGIC, 0x60, struct kdbus_cmd_match),
- KDBUS_CMD_MATCH_REMOVE = _IOWR(KDBUS_IOC_MAGIC, 0x61, struct kdbus_cmd_match),
- KDBUS_CMD_MONITOR = _IOWR(KDBUS_IOC_MAGIC, 0x62, struct kdbus_cmd_monitor),
+ KDBUS_CMD_CONN_INFO = _IOWR(KDBUS_IOC_MAGIC, 0x60, struct kdbus_cmd_conn_info),
- /* kdbus ep node commands: require ep owner state */
- KDBUS_CMD_EP_POLICY_SET = _IOWR(KDBUS_IOC_MAGIC, 0x70, struct kdbus_cmd_policy),
+ KDBUS_CMD_MATCH_ADD = _IOW (KDBUS_IOC_MAGIC, 0x70, struct kdbus_cmd_match),
+ KDBUS_CMD_MATCH_REMOVE = _IOW (KDBUS_IOC_MAGIC, 0x71, struct kdbus_cmd_match),
- /* kdbus ep node commands: */
- KDBUS_CMD_MEMFD_NEW = _IOWR(KDBUS_IOC_MAGIC, 0x80, int *),
+ KDBUS_CMD_EP_POLICY_SET = _IOW (KDBUS_IOC_MAGIC, 0x80, struct kdbus_cmd_policy),
- /* kdbus memfd commands: */
- KDBUS_CMD_MEMFD_SIZE_GET = _IOWR(KDBUS_IOC_MAGIC, 0x81, __u64 *),
- KDBUS_CMD_MEMFD_SIZE_SET = _IOWR(KDBUS_IOC_MAGIC, 0x82, __u64 *),
- KDBUS_CMD_MEMFD_SEAL_GET = _IOWR(KDBUS_IOC_MAGIC, 0x83, int *),
- KDBUS_CMD_MEMFD_SEAL_SET = _IOWR(KDBUS_IOC_MAGIC, 0x84, int),
+ KDBUS_CMD_MEMFD_NEW = _IOR (KDBUS_IOC_MAGIC, 0x90, int *),
+ KDBUS_CMD_MEMFD_SIZE_GET = _IOR (KDBUS_IOC_MAGIC, 0x91, __u64 *),
+ KDBUS_CMD_MEMFD_SIZE_SET = _IOW (KDBUS_IOC_MAGIC, 0x92, __u64 *),
+ KDBUS_CMD_MEMFD_SEAL_GET = _IOR (KDBUS_IOC_MAGIC, 0x93, int *),
+ KDBUS_CMD_MEMFD_SEAL_SET = _IO (KDBUS_IOC_MAGIC, 0x94),
};
+
+/*
+ * errno - api error codes
+ * @E2BIG: A message contains too many records or items.
+ * @EADDRINUSE: A well-known bus name is already taken by another
+ * connection.
+ * @EADDRNOTAVAIL: A message flagged not to activate a service, addressed
+ * a service which is not currently running.
+ * @EAGAIN: No messages are queued at the moment.
+ * @EBADF: File descriptors passed with the message are not valid.
+ * @EBADFD: A bus connection is in a corrupted state.
+ * @EBADMSG: Passed data contains a combination of conflicting or
+ * inconsistent types.
+ * @ECONNRESET: A connection is shut down, no further operations are
+ * possible.
+ * @ECOMM: A peer does not accept the file descriptors addressed
+ * to it.
+ * @EDESTADDRREQ: The well-known bus name is required but missing.
+ * @EDOM: The size of data does not match the expectations. Used
+ * for the size of the bloom filter bit field.
+ * @EEXIST: A requested namespace, bus or endpoint with the same
+ * name already exists. A specific data type, which is
+ * only expected once, is provided multiple times.
+ * @EFAULT: The supplied memory could not be accessed, or the data
+ * is not properly aligned.
+ * @EINVAL: The provided data does not match its type or other
+ * expectations, like a string which is not NUL terminated,
+ * or a string length that points behind the first
+ * \0-byte in the string.
+ * @EMEDIUMTYPE: A file descriptor which is not a kdbus memfd was
+ * refused to send as KDBUS_MSG_PAYLOAD_MEMFD.
+ * @EMFILE: Too many file descriptors have been supplied with a
+ * message.
+ * @EMSGSIZE: The supplied data is larger than the allowed maximum
+ * size.
+ * @ENAMETOOLONG: The requested name is larger than the allowed maximum
+ * size.
+ * @ENOBUFS: There is no space left for the submitted data to fit
+ * into the receiver's pool.
+ * @ENOMEM: Out of memory.
+ * @ENOSYS: The requested functionality is not available.
+ * @ENOTCONN: The addressed peer is not an active connection.
+ * @ENOTSUPP: The feature negotiation failed, a not supported feature
+ * was requested, or an unknown item type was received.
+ * @ENOTTY: An unknown ioctl command was received.
+ * @ENOTUNIQ: A specific data type was addressed to a broadcast
+ * address, but only direct addresses support this kind of
+ * data.
+ * @ENXIO: A unique address does not exist, or an offset in the
+ * receiver's pool does not represent a queued message.
+ * @EPERM: The policy prevented an operation. The requested
+ * resource is owned by another entity.
+ * @ESHUTDOWN: A namespace or endpoint is currently shutting down;
+ * no further operations will be possible.
+ * @ESRCH: A requested well-known bus name is not found.
+ * @ETXTBSY: A kdbus memfd file cannot be sealed or the seal removed,
+ * because it is shared with other processes or still
+ * mmap()ed.
+ * @EXFULL: The size limits in the pool are reached, no data of
+ * the size tried to submit can be queued.
+ */
#endif