2 * This is <linux/capability.h>
4 * Andrew G. Morgan <morgan@kernel.org>
5 * Alexander Kjeldaas <astor@guardian.no>
6 * with help from Aleph1, Roland Buresund and Andrew Main.
8 * See here for the libcap library ("POSIX draft" compliance):
10 * ftp://linux.kernel.org/pub/linux/libs/security/linux-privs/kernel-2.6/
13 #ifndef _LINUX_CAPABILITY_H
14 #define _LINUX_CAPABILITY_H
16 #include <linux/types.h>
20 /* User-level do most of the mapping between kernel and user
21 capabilities based on the version tag given by the kernel. The
22 kernel might be somewhat backwards compatible, but don't bet on
25 /* Note, cap_t, is defined by POSIX (draft) to be an "opaque" pointer to
26 a set of three capability sets. The transposition of 3*the
27 following structure to such a composite is better handled in a user
28 library since the draft standard requires the use of malloc/free
31 #define _LINUX_CAPABILITY_VERSION_1 0x19980330
32 #define _LINUX_CAPABILITY_U32S_1 1
34 #define _LINUX_CAPABILITY_VERSION_2 0x20071026 /* deprecated - use v3 */
35 #define _LINUX_CAPABILITY_U32S_2 2
37 #define _LINUX_CAPABILITY_VERSION_3 0x20080522
38 #define _LINUX_CAPABILITY_U32S_3 2
40 typedef struct __user_cap_header_struct {
43 } __user *cap_user_header_t;
45 typedef struct __user_cap_data_struct {
49 } __user *cap_user_data_t;
52 #define XATTR_CAPS_SUFFIX "capability"
53 #define XATTR_NAME_CAPS XATTR_SECURITY_PREFIX XATTR_CAPS_SUFFIX
55 #define VFS_CAP_REVISION_MASK 0xFF000000
56 #define VFS_CAP_FLAGS_MASK ~VFS_CAP_REVISION_MASK
57 #define VFS_CAP_FLAGS_EFFECTIVE 0x000001
59 #define VFS_CAP_REVISION_1 0x01000000
60 #define VFS_CAP_U32_1 1
61 #define XATTR_CAPS_SZ_1 (sizeof(__le32)*(1 + 2*VFS_CAP_U32_1))
63 #define VFS_CAP_REVISION_2 0x02000000
64 #define VFS_CAP_U32_2 2
65 #define XATTR_CAPS_SZ_2 (sizeof(__le32)*(1 + 2*VFS_CAP_U32_2))
67 #define XATTR_CAPS_SZ XATTR_CAPS_SZ_2
68 #define VFS_CAP_U32 VFS_CAP_U32_2
69 #define VFS_CAP_REVISION VFS_CAP_REVISION_2
71 #ifdef CONFIG_SECURITY_FILE_CAPABILITIES
72 extern int file_caps_enabled;
76 __le32 magic_etc; /* Little endian */
78 __le32 permitted; /* Little endian */
79 __le32 inheritable; /* Little endian */
86 * Backwardly compatible definition for source code - trapped in a
87 * 32-bit world. If you find you need this, please consider using
88 * libcap to untrap yourself...
90 #define _LINUX_CAPABILITY_VERSION _LINUX_CAPABILITY_VERSION_1
91 #define _LINUX_CAPABILITY_U32S _LINUX_CAPABILITY_U32S_1
95 #define _KERNEL_CAPABILITY_VERSION _LINUX_CAPABILITY_VERSION_3
96 #define _KERNEL_CAPABILITY_U32S _LINUX_CAPABILITY_U32S_3
98 typedef struct kernel_cap_struct {
99 __u32 cap[_KERNEL_CAPABILITY_U32S];
102 #define _USER_CAP_HEADER_SIZE (sizeof(struct __user_cap_header_struct))
103 #define _KERNEL_CAP_T_SIZE (sizeof(kernel_cap_t))
109 ** POSIX-draft defined capabilities.
112 /* In a system with the [_POSIX_CHOWN_RESTRICTED] option defined, this
113 overrides the restriction of changing file ownership and group
118 /* Override all DAC access, including ACL execute access if
119 [_POSIX_ACL] is defined. Excluding DAC access covered by
120 CAP_LINUX_IMMUTABLE. */
122 #define CAP_DAC_OVERRIDE 1
124 /* Overrides all DAC restrictions regarding read and search on files
125 and directories, including ACL restrictions if [_POSIX_ACL] is
126 defined. Excluding DAC access covered by CAP_LINUX_IMMUTABLE. */
128 #define CAP_DAC_READ_SEARCH 2
130 /* Overrides all restrictions about allowed operations on files, where
131 file owner ID must be equal to the user ID, except where CAP_FSETID
132 is applicable. It doesn't override MAC and DAC restrictions. */
136 /* Overrides the following restrictions that the effective user ID
137 shall match the file owner ID when setting the S_ISUID and S_ISGID
138 bits on that file; that the effective group ID (or one of the
139 supplementary group IDs) shall match the file owner ID when setting
140 the S_ISGID bit on that file; that the S_ISUID and S_ISGID bits are
141 cleared on successful return from chown(2) (not implemented). */
145 /* Overrides the restriction that the real or effective user ID of a
146 process sending a signal must match the real or effective user ID
147 of the process receiving the signal. */
151 /* Allows setgid(2) manipulation */
152 /* Allows setgroups(2) */
153 /* Allows forged gids on socket credentials passing. */
157 /* Allows set*uid(2) manipulation (including fsuid). */
158 /* Allows forged pids on socket credentials passing. */
164 ** Linux-specific capabilities
167 /* Without VFS support for capabilities:
168 * Transfer any capability in your permitted set to any pid,
169 * remove any capability in your permitted set from any pid
170 * With VFS support for capabilities (neither of above, but)
171 * Add any capability from current's capability bounding set
172 * to the current process' inheritable set
173 * Allow taking bits out of capability bounding set
174 * Allow modification of the securebits for a process
177 #define CAP_SETPCAP 8
179 /* Allow modification of S_IMMUTABLE and S_APPEND file attributes */
181 #define CAP_LINUX_IMMUTABLE 9
183 /* Allows binding to TCP/UDP sockets below 1024 */
184 /* Allows binding to ATM VCIs below 32 */
186 #define CAP_NET_BIND_SERVICE 10
188 /* Allow broadcasting, listen to multicast */
190 #define CAP_NET_BROADCAST 11
192 /* Allow interface configuration */
193 /* Allow administration of IP firewall, masquerading and accounting */
194 /* Allow setting debug option on sockets */
195 /* Allow modification of routing tables */
196 /* Allow setting arbitrary process / process group ownership on
198 /* Allow binding to any address for transparent proxying */
199 /* Allow setting TOS (type of service) */
200 /* Allow setting promiscuous mode */
201 /* Allow clearing driver statistics */
202 /* Allow multicasting */
203 /* Allow read/write of device-specific registers */
204 /* Allow activation of ATM control sockets */
206 #define CAP_NET_ADMIN 12
208 /* Allow use of RAW sockets */
209 /* Allow use of PACKET sockets */
211 #define CAP_NET_RAW 13
213 /* Allow locking of shared memory segments */
214 /* Allow mlock and mlockall (which doesn't really have anything to do
217 #define CAP_IPC_LOCK 14
219 /* Override IPC ownership checks */
221 #define CAP_IPC_OWNER 15
223 /* Insert and remove kernel modules - modify kernel without limit */
224 #define CAP_SYS_MODULE 16
226 /* Allow ioperm/iopl access */
227 /* Allow sending USB messages to any device via /proc/bus/usb */
229 #define CAP_SYS_RAWIO 17
231 /* Allow use of chroot() */
233 #define CAP_SYS_CHROOT 18
235 /* Allow ptrace() of any process */
237 #define CAP_SYS_PTRACE 19
239 /* Allow configuration of process accounting */
241 #define CAP_SYS_PACCT 20
243 /* Allow configuration of the secure attention key */
244 /* Allow administration of the random device */
245 /* Allow examination and configuration of disk quotas */
246 /* Allow configuring the kernel's syslog (printk behaviour) */
247 /* Allow setting the domainname */
248 /* Allow setting the hostname */
249 /* Allow calling bdflush() */
250 /* Allow mount() and umount(), setting up new smb connection */
251 /* Allow some autofs root ioctls */
252 /* Allow nfsservctl */
253 /* Allow VM86_REQUEST_IRQ */
254 /* Allow to read/write pci config on alpha */
255 /* Allow irix_prctl on mips (setstacksize) */
256 /* Allow flushing all cache on m68k (sys_cacheflush) */
257 /* Allow removing semaphores */
258 /* Used instead of CAP_CHOWN to "chown" IPC message queues, semaphores
260 /* Allow locking/unlocking of shared memory segment */
261 /* Allow turning swap on/off */
262 /* Allow forged pids on socket credentials passing */
263 /* Allow setting readahead and flushing buffers on block devices */
264 /* Allow setting geometry in floppy driver */
265 /* Allow turning DMA on/off in xd driver */
266 /* Allow administration of md devices (mostly the above, but some
268 /* Allow tuning the ide driver */
269 /* Allow access to the nvram device */
270 /* Allow administration of apm_bios, serial and bttv (TV) device */
271 /* Allow manufacturer commands in isdn CAPI support driver */
272 /* Allow reading non-standardized portions of pci configuration space */
273 /* Allow DDI debug ioctl on sbpcd driver */
274 /* Allow setting up serial ports */
275 /* Allow sending raw qic-117 commands */
276 /* Allow enabling/disabling tagged queuing on SCSI controllers and sending
277 arbitrary SCSI commands */
278 /* Allow setting encryption key on loopback filesystem */
279 /* Allow setting zone reclaim policy */
281 #define CAP_SYS_ADMIN 21
283 /* Allow use of reboot() */
285 #define CAP_SYS_BOOT 22
287 /* Allow raising priority and setting priority on other (different
289 /* Allow use of FIFO and round-robin (realtime) scheduling on own
290 processes and setting the scheduling algorithm used by another
292 /* Allow setting cpu affinity on other processes */
294 #define CAP_SYS_NICE 23
296 /* Override resource limits. Set resource limits. */
297 /* Override quota limits. */
298 /* Override reserved space on ext2 filesystem */
299 /* Modify data journaling mode on ext3 filesystem (uses journaling
301 /* NOTE: ext2 honors fsuid when checking for resource overrides, so
302 you can override using fsuid too */
303 /* Override size restrictions on IPC message queues */
304 /* Allow more than 64hz interrupts from the real-time clock */
305 /* Override max number of consoles on console allocation */
306 /* Override max number of keymaps */
308 #define CAP_SYS_RESOURCE 24
310 /* Allow manipulation of system clock */
311 /* Allow irix_stime on mips */
312 /* Allow setting the real-time clock */
314 #define CAP_SYS_TIME 25
316 /* Allow configuration of tty devices */
317 /* Allow vhangup() of tty */
319 #define CAP_SYS_TTY_CONFIG 26
321 /* Allow the privileged aspects of mknod() */
325 /* Allow taking of leases on files */
329 #define CAP_AUDIT_WRITE 29
331 #define CAP_AUDIT_CONTROL 30
333 #define CAP_SETFCAP 31
335 /* Override MAC access.
336 The base kernel enforces no MAC policy.
337 An LSM may enforce a MAC policy, and if it does and it chooses
338 to implement capability based overrides of that policy, this is
339 the capability it should use to do so. */
341 #define CAP_MAC_OVERRIDE 32
343 /* Allow MAC configuration or state changes.
344 The base kernel requires no MAC configuration.
345 An LSM may enforce a MAC policy, and if it does and it chooses
346 to implement capability based checks on modifications to that
347 policy or the data required to maintain it, this is the
348 capability it should use to do so. */
350 #define CAP_MAC_ADMIN 33
352 #define CAP_LAST_CAP CAP_MAC_ADMIN
354 #define cap_valid(x) ((x) >= 0 && (x) <= CAP_LAST_CAP)
357 * Bit location of each capability (used by user-space library and kernel)
360 #define CAP_TO_INDEX(x) ((x) >> 5) /* 1 << 5 == bits in __u32 */
361 #define CAP_TO_MASK(x) (1 << ((x) & 31)) /* mask for indexed __u32 */
366 * Internal kernel functions only
369 #define CAP_FOR_EACH_U32(__capi) \
370 for (__capi = 0; __capi < _KERNEL_CAPABILITY_U32S; ++__capi)
372 # define CAP_FS_MASK_B0 (CAP_TO_MASK(CAP_CHOWN) \
373 | CAP_TO_MASK(CAP_DAC_OVERRIDE) \
374 | CAP_TO_MASK(CAP_DAC_READ_SEARCH) \
375 | CAP_TO_MASK(CAP_FOWNER) \
376 | CAP_TO_MASK(CAP_FSETID))
378 # define CAP_FS_MASK_B1 (CAP_TO_MASK(CAP_MAC_OVERRIDE))
380 #if _KERNEL_CAPABILITY_U32S != 2
381 # error Fix up hand-coded capability macro initializers
382 #else /* HAND-CODED capability initializers */
384 # define CAP_EMPTY_SET ((kernel_cap_t){{ 0, 0 }})
385 # define CAP_FULL_SET ((kernel_cap_t){{ ~0, ~0 }})
386 # define CAP_INIT_EFF_SET ((kernel_cap_t){{ ~CAP_TO_MASK(CAP_SETPCAP), ~0 }})
387 # define CAP_FS_SET ((kernel_cap_t){{ CAP_FS_MASK_B0, CAP_FS_MASK_B1 } })
388 # define CAP_NFSD_SET ((kernel_cap_t){{ CAP_FS_MASK_B0|CAP_TO_MASK(CAP_SYS_RESOURCE), \
391 #endif /* _KERNEL_CAPABILITY_U32S != 2 */
393 #define CAP_INIT_INH_SET CAP_EMPTY_SET
395 # define cap_clear(c) do { (c) = __cap_empty_set; } while (0)
396 # define cap_set_full(c) do { (c) = __cap_full_set; } while (0)
397 # define cap_set_init_eff(c) do { (c) = __cap_init_eff_set; } while (0)
399 #define cap_raise(c, flag) ((c).cap[CAP_TO_INDEX(flag)] |= CAP_TO_MASK(flag))
400 #define cap_lower(c, flag) ((c).cap[CAP_TO_INDEX(flag)] &= ~CAP_TO_MASK(flag))
401 #define cap_raised(c, flag) ((c).cap[CAP_TO_INDEX(flag)] & CAP_TO_MASK(flag))
403 #define CAP_BOP_ALL(c, a, b, OP) \
406 CAP_FOR_EACH_U32(__capi) { \
407 c.cap[__capi] = a.cap[__capi] OP b.cap[__capi]; \
411 #define CAP_UOP_ALL(c, a, OP) \
414 CAP_FOR_EACH_U32(__capi) { \
415 c.cap[__capi] = OP a.cap[__capi]; \
419 static inline kernel_cap_t cap_combine(const kernel_cap_t a,
420 const kernel_cap_t b)
423 CAP_BOP_ALL(dest, a, b, |);
427 static inline kernel_cap_t cap_intersect(const kernel_cap_t a,
428 const kernel_cap_t b)
431 CAP_BOP_ALL(dest, a, b, &);
435 static inline kernel_cap_t cap_drop(const kernel_cap_t a,
436 const kernel_cap_t drop)
439 CAP_BOP_ALL(dest, a, drop, &~);
443 static inline kernel_cap_t cap_invert(const kernel_cap_t c)
446 CAP_UOP_ALL(dest, c, ~);
450 static inline int cap_isclear(const kernel_cap_t a)
453 CAP_FOR_EACH_U32(__capi) {
454 if (a.cap[__capi] != 0)
461 * Check if "a" is a subset of "set".
462 * return 1 if ALL of the capabilities in "a" are also in "set"
463 * cap_issubset(0101, 1111) will return 1
464 * return 0 if ANY of the capabilities in "a" are not in "set"
465 * cap_issubset(1111, 0101) will return 0
467 static inline int cap_issubset(const kernel_cap_t a, const kernel_cap_t set)
470 dest = cap_drop(a, set);
471 return cap_isclear(dest);
474 /* Used to decide between falling back on the old suser() or fsuser(). */
476 static inline int cap_is_fs_cap(int cap)
478 const kernel_cap_t __cap_fs_set = CAP_FS_SET;
479 return !!(CAP_TO_MASK(cap) & __cap_fs_set.cap[CAP_TO_INDEX(cap)]);
482 static inline kernel_cap_t cap_drop_fs_set(const kernel_cap_t a)
484 const kernel_cap_t __cap_fs_set = CAP_FS_SET;
485 return cap_drop(a, __cap_fs_set);
488 static inline kernel_cap_t cap_raise_fs_set(const kernel_cap_t a,
489 const kernel_cap_t permitted)
491 const kernel_cap_t __cap_fs_set = CAP_FS_SET;
492 return cap_combine(a,
493 cap_intersect(permitted, __cap_fs_set));
496 static inline kernel_cap_t cap_drop_nfsd_set(const kernel_cap_t a)
498 const kernel_cap_t __cap_fs_set = CAP_NFSD_SET;
499 return cap_drop(a, __cap_fs_set);
502 static inline kernel_cap_t cap_raise_nfsd_set(const kernel_cap_t a,
503 const kernel_cap_t permitted)
505 const kernel_cap_t __cap_nfsd_set = CAP_NFSD_SET;
506 return cap_combine(a,
507 cap_intersect(permitted, __cap_nfsd_set));
510 extern const kernel_cap_t __cap_empty_set;
511 extern const kernel_cap_t __cap_full_set;
512 extern const kernel_cap_t __cap_init_eff_set;
514 kernel_cap_t cap_set_effective(const kernel_cap_t pE_new);
517 * has_capability - Determine if a task has a superior capability available
518 * @t: The task in question
519 * @cap: The capability to be tested for
521 * Return true if the specified task has the given superior capability
522 * currently in effect, false if not.
524 * Note that this does not set PF_SUPERPRIV on the task.
526 #define has_capability(t, cap) (security_capable((t), (cap)) == 0)
528 extern int capable(int cap);
530 #endif /* __KERNEL__ */
532 #endif /* !_LINUX_CAPABILITY_H */