X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=src%2Flibsystemd-bus%2Fkdbus.h;h=4896c38dfe30d2e07b67c7f60709109e6fd100c3;hp=aac7b8435273acfed6438f3fe96bb8927afeb8c3;hb=ec76ec1fde7da753676b18ff45926740fcd08072;hpb=b1454bf05cecb22e3009db204bf17ec72537c539 diff --git a/src/libsystemd-bus/kdbus.h b/src/libsystemd-bus/kdbus.h index aac7b8435..4896c38df 100644 --- a/src/libsystemd-bus/kdbus.h +++ b/src/libsystemd-bus/kdbus.h @@ -2,6 +2,8 @@ * Copyright (C) 2013 Kay Sievers * Copyright (C) 2013 Greg Kroah-Hartman * Copyright (C) 2013 Linux Foundation + * Copyright (C) 2013 Lennart Poettering + * Copyright (C) 2013 Daniel Mack * * kdbus is free software; you can redistribute it and/or modify it under * the terms of the GNU Lesser General Public License as published by the @@ -19,399 +21,819 @@ #endif #define KDBUS_IOC_MAGIC 0x95 +#define KDBUS_SRC_ID_KERNEL (0) +#define KDBUS_DST_ID_NAME (0) +#define KDBUS_MATCH_SRC_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_CMD_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_CMD_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 Data Types */ -enum { - /* Filled in by userspace */ - KDBUS_MSG_NULL, /* empty record */ - KDBUS_MSG_PAYLOAD, /* .data */ - KDBUS_MSG_PAYLOAD_VEC, /* .data_vec */ - KDBUS_MSG_UNIX_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 */ - - /* Filled in by kernelspace */ - KDBUS_MSG_SRC_NAMES = 0x200,/* 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 = 0x400,/* .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_ID_CHANGE, /* .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 size; + union { + __u64 address; + __u64 offset; + }; }; -struct kdbus_vec { - __u64 address; +/** + * 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_msg_data - chain of data blocks + * struct kdbus_name - a registered well-known name with its flags + * @flags: flags from KDBUS_NAME_* + * @name: well-known name * - * size: overall data record size - * type: kdbus_msg_data_type of data + * Attached to: + * KDBUS_ITEM_NAME */ -struct kdbus_msg_data { +struct kdbus_name { + __u64 flags; + char name[0]; +}; + +/** + * 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 + * + * 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_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_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]; - /* data vector */ + __u64 id; struct kdbus_vec vec; - - /* specific fields */ - int fds[0]; /* int array of file descriptors */ struct kdbus_creds creds; struct kdbus_audit audit; struct kdbus_timestamp timestamp; - struct kdbus_manager_msg_name_change name_change; - struct kdbus_manager_msg_id_change id_change; + struct kdbus_name name; + struct kdbus_memfd memfd; + int fds[0]; + struct kdbus_notify_name_change name_change; + struct kdbus_notify_id_change id_change; + struct kdbus_policy policy; }; }; -enum { - KDBUS_MSG_FLAGS_EXPECT_REPLY = 1, - KDBUS_MSG_FLAGS_NO_AUTO_START = 2, /* possibly? */ +/** + * 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_NONE = 0, - 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_* - * data_size: overall message size - * data: 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_msg_data items[0]; -}; - -enum { - KDBUS_POLICY_NAME, - KDBUS_POLICY_ACCESS, -}; + struct kdbus_item items[0]; +} __attribute__((aligned(8))); -enum { - KDBUS_POLICY_USER, - KDBUS_POLICY_GROUP, - KDBUS_POLICY_WORLD, -}; - -enum { - KDBUS_POLICY_RECV = 4, - KDBUS_POLICY_SEND = 2, - KDBUS_POLICY_OWN = 1, +/** + * 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, }; -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; - }; +/** + * 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_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))); -enum { - KDBUS_CMD_HELLO_STARTER = 1 << 0, - KDBUS_CMD_HELLO_ACCEPT_FD = 1 << 1, - KDBUS_CMD_HELLO_ACCEPT_MMAP = 1 << 2, - - /* The following have an effect on directed messages only -- - * not for broadcasts */ - KDBUS_CMD_HELLO_ATTACH_COMM = 1 << 10, - KDBUS_CMD_HELLO_ATTACH_EXE = 1 << 11, - KDBUS_CMD_HELLO_ATTACH_CMDLINE = 1 << 12, - KDBUS_CMD_HELLO_ATTACH_CGROUP = 1 << 13, - KDBUS_CMD_HELLO_ATTACH_CAPS = 1 << 14, - KDBUS_CMD_HELLO_ATTACH_SECLABEL = 1 << 15, - KDBUS_CMD_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, }; -/* Flags for kdbus_cmd_bus_make, kdbus_cmd_ep_make and - * kdbus_cmd_ns_make */ -enum { - KDBUS_ACCESS_GROUP = 1, - KDBUS_ACCESS_WORLD = 2, - KDBUS_POLICY_OPEN = 4, +/** + * 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 { - /* 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_CMD_HELLO */ - - /* userspace → kernel */ - __u64 pid; /* To allow translator services which - * connect to the bus on behalf of - * somebody else, allow specifiying - * the PID of the client to connect on - * behalf on. Normal clients should - * pass this as 0 (i.e. to do things - * under their own PID). Priviliged - * clients can pass != 0, to operate - * on behalf of somebody else. */ - - /* 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; /* peer id */ - __u64 bloom_size; /* The bloom filter size chosen by the - * bus owner */ -}; - -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 cgroup_id; /* the cgroup hierarchy ID for which - * to attach cgroup membership paths - * to messages. 0 if no cgroup data - * shall be attached. */ - __u64 bloom_size; /* Size of the bloom filter for this bus. */ - char name[0]; -}; + __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))); -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. */ - char name[0]; +/* 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, }; -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. */ - char name[0]; -}; - -enum { - /* userspace → kernel */ - KDBUS_CMD_NAME_REPLACE_EXISTING = 1, - KDBUS_CMD_NAME_QUEUE = 2, - KDBUS_CMD_NAME_ALLOW_REPLACEMENT = 4, + __u64 flags; + struct kdbus_item items[0]; +} __attribute__((aligned(8))); - /* kernel → userspace */ - KDBUS_CMD_NAME_IN_QUEUE = 0x200, +/** + * 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]; -}; - -struct kdbus_cmd_names { - __u64 size; - struct kdbus_cmd_name names[0]; -}; - -enum { - KDBUS_CMD_NAME_INFO_ITEM_NAME, - KDBUS_CMD_NAME_INFO_ITEM_SECLABEL, - KDBUS_CMD_NAME_INFO_ITEM_AUDIT, -}; +} __attribute__((aligned(8))); -struct kdbus_cmd_name_info_item { - __u64 size; - __u64 type; - __u8 items[0]; +/** + * 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_name_info { - __u64 size; /* overall size of info */ +/** + * 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 id; /* either ID, or 0 and _ITEM_NAME follows */ - struct kdbus_creds creds; - struct kdbus_cmd_name_info_item item[0]; /* list of item records */ -}; + __u64 offset; +} __attribute__((aligned(8))); -enum { - KDBUS_CMD_MATCH_BLOOM, /* Matches a mask blob against KDBUS_MSG_BLOOM */ - KDBUS_CMD_MATCH_SRC_NAME, /* Matches a name string against KDBUS_MSG_SRC_NAMES */ - KDBUS_CMD_MATCH_NAME_ADD, /* Matches a name string against KDBUS_MSG_NAME_ADD */ - KDBUS_CMD_MATCH_NAME_REMOVE, /* Matches a name string against KDBUS_MSG_NAME_REMOVE */ - KDBUS_CMD_MATCH_NAME_CHANGE, /* Matches a name string against KDBUS_MSG_NAME_CHANGE */ - KDBUS_CMD_MATCH_ID_ADD, /* Matches an ID against KDBUS_MSG_ID_ADD */ - KDBUS_CMD_MATCH_ID_REMOVE, /* Matches an ID against KDBUS_MSG_ID_REMOVE */ - KDBUS_CMD_MATCH_ID_CHANGE, /* Matches an ID against KDBUS_MSG_ID_CHANGE */ +/** + * 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]; }; -struct kdbus_cmd_match_item { +/** + * 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 type; - union { - __u64 id; - __u8 data[0]; - char str[0]; - }; -}; + __u64 flags; + __u64 id; + __u64 offset; + char name[0]; +} __attribute__((aligned(8))); -struct kdbus_cmd_match { +/** + * 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; /* 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 */ - struct kdbus_cmd_match_item items[0]; + __u64 id; + __u64 flags; + struct kdbus_item items[0]; }; -struct kdbus_cmd_monitor { - __u64 id; /* We allow setting the monitor flag of other peers */ - int enabled; /* A boolean to enable/disable monitoring */ +/** + * enum kdbus_match_type - type of match record + * @KDBUS_MATCH_BLOOM: Matches against KDBUS_MSG_BLOOM + * @KDBUS_MATCH_SRC_NAME: Matches a name string + * @KDBUS_MATCH_NAME_ADD: Matches a name string + * @KDBUS_MATCH_NAME_REMOVE: Matches a name string + * @KDBUS_MATCH_NAME_CHANGE: Matches a name string + * @KDBUS_MATCH_ID_ADD: Matches an ID + * @KDBUS_MATCH_ID_REMOVE: Matches an ID + */ +enum kdbus_match_type { + _KDBUS_MATCH_NULL, + KDBUS_MATCH_BLOOM, + KDBUS_MATCH_SRC_NAME, + KDBUS_MATCH_NAME_ADD, + KDBUS_MATCH_NAME_REMOVE, + KDBUS_MATCH_NAME_CHANGE, + KDBUS_MATCH_ID_ADD, + KDBUS_MATCH_ID_REMOVE, }; -/* FD states: - * control nodes: unset - * bus owner (via KDBUS_CMD_BUS_MAKE) - * ns owner (via KDBUS_CMD_NS_MAKE) +/** + * 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. + * @src_id: The source ID to match against. Use + * KDBUS_MATCH_SRC_ID_ANY or any other value for a unique + * match. + * @items: A list of items for additional information * - * 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) + * This structure is used with the KDBUS_CMD_ADD_MATCH and + * KDBUS_CMD_REMOVE_MATCH ioctl. */ -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), +struct kdbus_cmd_match { + __u64 size; + __u64 id; + __u64 cookie; + __u64 src_id; + struct kdbus_item items[0]; +} __attribute__((aligned(8))); - /* kdbus control node commands: require bus owner state */ - KDBUS_CMD_BUS_POLICY_SET = _IOWR(KDBUS_IOC_MAGIC, 0x20, struct kdbus_cmd_policy), +/** + * 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), - /* kdbus ep node commands: require unset state */ - KDBUS_CMD_EP_MAKE = _IOWR(KDBUS_IOC_MAGIC, 0x30, struct kdbus_cmd_ep_make), - KDBUS_CMD_HELLO = _IOWR(KDBUS_IOC_MAGIC, 0x31, struct kdbus_cmd_hello), + 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_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_CMD_EP_POLICY_SET = _IOW (KDBUS_IOC_MAGIC, 0x80, struct kdbus_cmd_policy), + + 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