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The C and C++ Include Header Files

/usr/include/linux/landlock.h


$ cat -n /usr/include/linux/landlock.h

     1	/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
     2	/*
     3	 * Landlock - User space API
     4	 *
     5	 * Copyright © 2017-2020 Mickaël Salaün <mic@digikod.net>
     6	 * Copyright © 2018-2020 ANSSI
     7	 */
     8	
     9	#ifndef _LINUX_LANDLOCK_H
    10	#define _LINUX_LANDLOCK_H
    11	
    12	#include <linux/types.h>
    13	
    14	/**
    15	 * struct landlock_ruleset_attr - Ruleset definition
    16	 *
    17	 * Argument of sys_landlock_create_ruleset().  This structure can grow in
    18	 * future versions.
    19	 */
    20	struct landlock_ruleset_attr {
    21		/**
    22		 * @handled_access_fs: Bitmask of actions (cf. `Filesystem flags`_)
    23		 * that is handled by this ruleset and should then be forbidden if no
    24		 * rule explicitly allow them: it is a deny-by-default list that should
    25		 * contain as much Landlock access rights as possible. Indeed, all
    26		 * Landlock filesystem access rights that are not part of
    27		 * handled_access_fs are allowed.  This is needed for backward
    28		 * compatibility reasons.  One exception is the
    29		 * %LANDLOCK_ACCESS_FS_REFER access right, which is always implicitly
    30		 * handled, but must still be explicitly handled to add new rules with
    31		 * this access right.
    32		 */
    33		__u64 handled_access_fs;
    34		/**
    35		 * @handled_access_net: Bitmask of actions (cf. `Network flags`_)
    36		 * that is handled by this ruleset and should then be forbidden if no
    37		 * rule explicitly allow them.
    38		 */
    39		__u64 handled_access_net;
    40	};
    41	
    42	/*
    43	 * sys_landlock_create_ruleset() flags:
    44	 *
    45	 * - %LANDLOCK_CREATE_RULESET_VERSION: Get the highest supported Landlock ABI
    46	 *   version.
    47	 */
    48	/* clang-format off */
    49	#define LANDLOCK_CREATE_RULESET_VERSION			(1U << 0)
    50	/* clang-format on */
    51	
    52	/**
    53	 * enum landlock_rule_type - Landlock rule type
    54	 *
    55	 * Argument of sys_landlock_add_rule().
    56	 */
    57	enum landlock_rule_type {
    58		/**
    59		 * @LANDLOCK_RULE_PATH_BENEATH: Type of a &struct
    60		 * landlock_path_beneath_attr .
    61		 */
    62		LANDLOCK_RULE_PATH_BENEATH = 1,
    63		/**
    64		 * @LANDLOCK_RULE_NET_PORT: Type of a &struct
    65		 * landlock_net_port_attr .
    66		 */
    67		LANDLOCK_RULE_NET_PORT,
    68	};
    69	
    70	/**
    71	 * struct landlock_path_beneath_attr - Path hierarchy definition
    72	 *
    73	 * Argument of sys_landlock_add_rule().
    74	 */
    75	struct landlock_path_beneath_attr {
    76		/**
    77		 * @allowed_access: Bitmask of allowed actions for this file hierarchy
    78		 * (cf. `Filesystem flags`_).
    79		 */
    80		__u64 allowed_access;
    81		/**
    82		 * @parent_fd: File descriptor, preferably opened with ``O_PATH``,
    83		 * which identifies the parent directory of a file hierarchy, or just a
    84		 * file.
    85		 */
    86		__s32 parent_fd;
    87		/*
    88		 * This struct is packed to avoid trailing reserved members.
    89		 * Cf. security/landlock/syscalls.c:build_check_abi()
    90		 */
    91	} __attribute__((packed));
    92	
    93	/**
    94	 * struct landlock_net_port_attr - Network port definition
    95	 *
    96	 * Argument of sys_landlock_add_rule().
    97	 */
    98	struct landlock_net_port_attr {
    99		/**
   100		 * @allowed_access: Bitmask of allowed access network for a port
   101		 * (cf. `Network flags`_).
   102		 */
   103		__u64 allowed_access;
   104		/**
   105		 * @port: Network port in host endianness.
   106		 *
   107		 * It should be noted that port 0 passed to :manpage:`bind(2)` will
   108		 * bind to an available port from a specific port range. This can be
   109		 * configured thanks to the ``/proc/sys/net/ipv4/ip_local_port_range``
   110		 * sysctl (also used for IPv6). A Landlock rule with port 0 and the
   111		 * ``LANDLOCK_ACCESS_NET_BIND_TCP`` right means that requesting to bind
   112		 * on port 0 is allowed and it will automatically translate to binding
   113		 * on the related port range.
   114		 */
   115		__u64 port;
   116	};
   117	
   118	/**
   119	 * DOC: fs_access
   120	 *
   121	 * A set of actions on kernel objects may be defined by an attribute (e.g.
   122	 * &struct landlock_path_beneath_attr) including a bitmask of access.
   123	 *
   124	 * Filesystem flags
   125	 * ~~~~~~~~~~~~~~~~
   126	 *
   127	 * These flags enable to restrict a sandboxed process to a set of actions on
   128	 * files and directories.  Files or directories opened before the sandboxing
   129	 * are not subject to these restrictions.
   130	 *
   131	 * A file can only receive these access rights:
   132	 *
   133	 * - %LANDLOCK_ACCESS_FS_EXECUTE: Execute a file.
   134	 * - %LANDLOCK_ACCESS_FS_WRITE_FILE: Open a file with write access. Note that
   135	 *   you might additionally need the %LANDLOCK_ACCESS_FS_TRUNCATE right in order
   136	 *   to overwrite files with :manpage:`open(2)` using ``O_TRUNC`` or
   137	 *   :manpage:`creat(2)`.
   138	 * - %LANDLOCK_ACCESS_FS_READ_FILE: Open a file with read access.
   139	 * - %LANDLOCK_ACCESS_FS_TRUNCATE: Truncate a file with :manpage:`truncate(2)`,
   140	 *   :manpage:`ftruncate(2)`, :manpage:`creat(2)`, or :manpage:`open(2)` with
   141	 *   ``O_TRUNC``. Whether an opened file can be truncated with
   142	 *   :manpage:`ftruncate(2)` is determined during :manpage:`open(2)`, in the
   143	 *   same way as read and write permissions are checked during
   144	 *   :manpage:`open(2)` using %LANDLOCK_ACCESS_FS_READ_FILE and
   145	 *   %LANDLOCK_ACCESS_FS_WRITE_FILE. This access right is available since the
   146	 *   third version of the Landlock ABI.
   147	 *
   148	 * A directory can receive access rights related to files or directories.  The
   149	 * following access right is applied to the directory itself, and the
   150	 * directories beneath it:
   151	 *
   152	 * - %LANDLOCK_ACCESS_FS_READ_DIR: Open a directory or list its content.
   153	 *
   154	 * However, the following access rights only apply to the content of a
   155	 * directory, not the directory itself:
   156	 *
   157	 * - %LANDLOCK_ACCESS_FS_REMOVE_DIR: Remove an empty directory or rename one.
   158	 * - %LANDLOCK_ACCESS_FS_REMOVE_FILE: Unlink (or rename) a file.
   159	 * - %LANDLOCK_ACCESS_FS_MAKE_CHAR: Create (or rename or link) a character
   160	 *   device.
   161	 * - %LANDLOCK_ACCESS_FS_MAKE_DIR: Create (or rename) a directory.
   162	 * - %LANDLOCK_ACCESS_FS_MAKE_REG: Create (or rename or link) a regular file.
   163	 * - %LANDLOCK_ACCESS_FS_MAKE_SOCK: Create (or rename or link) a UNIX domain
   164	 *   socket.
   165	 * - %LANDLOCK_ACCESS_FS_MAKE_FIFO: Create (or rename or link) a named pipe.
   166	 * - %LANDLOCK_ACCESS_FS_MAKE_BLOCK: Create (or rename or link) a block device.
   167	 * - %LANDLOCK_ACCESS_FS_MAKE_SYM: Create (or rename or link) a symbolic link.
   168	 * - %LANDLOCK_ACCESS_FS_REFER: Link or rename a file from or to a different
   169	 *   directory (i.e. reparent a file hierarchy).
   170	 *
   171	 *   This access right is available since the second version of the Landlock
   172	 *   ABI.
   173	 *
   174	 *   This is the only access right which is denied by default by any ruleset,
   175	 *   even if the right is not specified as handled at ruleset creation time.
   176	 *   The only way to make a ruleset grant this right is to explicitly allow it
   177	 *   for a specific directory by adding a matching rule to the ruleset.
   178	 *
   179	 *   In particular, when using the first Landlock ABI version, Landlock will
   180	 *   always deny attempts to reparent files between different directories.
   181	 *
   182	 *   In addition to the source and destination directories having the
   183	 *   %LANDLOCK_ACCESS_FS_REFER access right, the attempted link or rename
   184	 *   operation must meet the following constraints:
   185	 *
   186	 *   * The reparented file may not gain more access rights in the destination
   187	 *     directory than it previously had in the source directory.  If this is
   188	 *     attempted, the operation results in an ``EXDEV`` error.
   189	 *
   190	 *   * When linking or renaming, the ``LANDLOCK_ACCESS_FS_MAKE_*`` right for the
   191	 *     respective file type must be granted for the destination directory.
   192	 *     Otherwise, the operation results in an ``EACCES`` error.
   193	 *
   194	 *   * When renaming, the ``LANDLOCK_ACCESS_FS_REMOVE_*`` right for the
   195	 *     respective file type must be granted for the source directory.  Otherwise,
   196	 *     the operation results in an ``EACCES`` error.
   197	 *
   198	 *   If multiple requirements are not met, the ``EACCES`` error code takes
   199	 *   precedence over ``EXDEV``.
   200	 *
   201	 * .. warning::
   202	 *
   203	 *   It is currently not possible to restrict some file-related actions
   204	 *   accessible through these syscall families: :manpage:`chdir(2)`,
   205	 *   :manpage:`stat(2)`, :manpage:`flock(2)`, :manpage:`chmod(2)`,
   206	 *   :manpage:`chown(2)`, :manpage:`setxattr(2)`, :manpage:`utime(2)`,
   207	 *   :manpage:`ioctl(2)`, :manpage:`fcntl(2)`, :manpage:`access(2)`.
   208	 *   Future Landlock evolutions will enable to restrict them.
   209	 */
   210	/* clang-format off */
   211	#define LANDLOCK_ACCESS_FS_EXECUTE			(1ULL << 0)
   212	#define LANDLOCK_ACCESS_FS_WRITE_FILE			(1ULL << 1)
   213	#define LANDLOCK_ACCESS_FS_READ_FILE			(1ULL << 2)
   214	#define LANDLOCK_ACCESS_FS_READ_DIR			(1ULL << 3)
   215	#define LANDLOCK_ACCESS_FS_REMOVE_DIR			(1ULL << 4)
   216	#define LANDLOCK_ACCESS_FS_REMOVE_FILE			(1ULL << 5)
   217	#define LANDLOCK_ACCESS_FS_MAKE_CHAR			(1ULL << 6)
   218	#define LANDLOCK_ACCESS_FS_MAKE_DIR			(1ULL << 7)
   219	#define LANDLOCK_ACCESS_FS_MAKE_REG			(1ULL << 8)
   220	#define LANDLOCK_ACCESS_FS_MAKE_SOCK			(1ULL << 9)
   221	#define LANDLOCK_ACCESS_FS_MAKE_FIFO			(1ULL << 10)
   222	#define LANDLOCK_ACCESS_FS_MAKE_BLOCK			(1ULL << 11)
   223	#define LANDLOCK_ACCESS_FS_MAKE_SYM			(1ULL << 12)
   224	#define LANDLOCK_ACCESS_FS_REFER			(1ULL << 13)
   225	#define LANDLOCK_ACCESS_FS_TRUNCATE			(1ULL << 14)
   226	/* clang-format on */
   227	
   228	/**
   229	 * DOC: net_access
   230	 *
   231	 * Network flags
   232	 * ~~~~~~~~~~~~~~~~
   233	 *
   234	 * These flags enable to restrict a sandboxed process to a set of network
   235	 * actions. This is supported since the Landlock ABI version 4.
   236	 *
   237	 * TCP sockets with allowed actions:
   238	 *
   239	 * - %LANDLOCK_ACCESS_NET_BIND_TCP: Bind a TCP socket to a local port.
   240	 * - %LANDLOCK_ACCESS_NET_CONNECT_TCP: Connect an active TCP socket to
   241	 *   a remote port.
   242	 */
   243	/* clang-format off */
   244	#define LANDLOCK_ACCESS_NET_BIND_TCP			(1ULL << 0)
   245	#define LANDLOCK_ACCESS_NET_CONNECT_TCP			(1ULL << 1)
   246	/* clang-format on */
   247	#endif /* _LINUX_LANDLOCK_H */