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>
17 #include <linux/compiler.h>
21 /* User-level do most of the mapping between kernel and user
22 capabilities based on the version tag given by the kernel. The
23 kernel might be somewhat backwards compatible, but don't bet on
26 /* Note, cap_t, is defined by POSIX (draft) to be an "opaque" pointer to
27 a set of three capability sets. The transposition of 3*the
28 following structure to such a composite is better handled in a user
29 library since the draft standard requires the use of malloc/free
32 #define _LINUX_CAPABILITY_VERSION_1 0x19980330
33 #define _LINUX_CAPABILITY_U32S_1 1
35 #define _LINUX_CAPABILITY_VERSION_2 0x20071026
36 #define _LINUX_CAPABILITY_U32S_2 2
38 #define _LINUX_CAPABILITY_VERSION _LINUX_CAPABILITY_VERSION_2
39 #define _LINUX_CAPABILITY_U32S _LINUX_CAPABILITY_U32S_2
41 typedef struct __user_cap_header_struct {
44 } __user *cap_user_header_t;
46 typedef struct __user_cap_data_struct {
50 } __user *cap_user_data_t;
53 #define XATTR_CAPS_SUFFIX "capability"
54 #define XATTR_NAME_CAPS XATTR_SECURITY_PREFIX XATTR_CAPS_SUFFIX
56 #define VFS_CAP_REVISION_MASK 0xFF000000
57 #define VFS_CAP_FLAGS_MASK ~VFS_CAP_REVISION_MASK
58 #define VFS_CAP_FLAGS_EFFECTIVE 0x000001
60 #define VFS_CAP_REVISION_1 0x01000000
61 #define VFS_CAP_U32_1 1
62 #define XATTR_CAPS_SZ_1 (sizeof(__le32)*(1 + 2*VFS_CAP_U32_1))
64 #define VFS_CAP_REVISION_2 0x02000000
65 #define VFS_CAP_U32_2 2
66 #define XATTR_CAPS_SZ_2 (sizeof(__le32)*(1 + 2*VFS_CAP_U32_2))
68 #define XATTR_CAPS_SZ XATTR_CAPS_SZ_2
69 #define VFS_CAP_U32 VFS_CAP_U32_2
70 #define VFS_CAP_REVISION VFS_CAP_REVISION_2
74 __le32 magic_etc; /* Little endian */
76 __le32 permitted; /* Little endian */
77 __le32 inheritable; /* Little endian */
83 typedef struct kernel_cap_struct {
84 __u32 cap[_LINUX_CAPABILITY_U32S];
87 #define _USER_CAP_HEADER_SIZE (sizeof(struct __user_cap_header_struct))
88 #define _KERNEL_CAP_T_SIZE (sizeof(kernel_cap_t))
94 ** POSIX-draft defined capabilities.
97 /* In a system with the [_POSIX_CHOWN_RESTRICTED] option defined, this
98 overrides the restriction of changing file ownership and group
103 /* Override all DAC access, including ACL execute access if
104 [_POSIX_ACL] is defined. Excluding DAC access covered by
105 CAP_LINUX_IMMUTABLE. */
107 #define CAP_DAC_OVERRIDE 1
109 /* Overrides all DAC restrictions regarding read and search on files
110 and directories, including ACL restrictions if [_POSIX_ACL] is
111 defined. Excluding DAC access covered by CAP_LINUX_IMMUTABLE. */
113 #define CAP_DAC_READ_SEARCH 2
115 /* Overrides all restrictions about allowed operations on files, where
116 file owner ID must be equal to the user ID, except where CAP_FSETID
117 is applicable. It doesn't override MAC and DAC restrictions. */
121 /* Overrides the following restrictions that the effective user ID
122 shall match the file owner ID when setting the S_ISUID and S_ISGID
123 bits on that file; that the effective group ID (or one of the
124 supplementary group IDs) shall match the file owner ID when setting
125 the S_ISGID bit on that file; that the S_ISUID and S_ISGID bits are
126 cleared on successful return from chown(2) (not implemented). */
130 /* Overrides the restriction that the real or effective user ID of a
131 process sending a signal must match the real or effective user ID
132 of the process receiving the signal. */
136 /* Allows setgid(2) manipulation */
137 /* Allows setgroups(2) */
138 /* Allows forged gids on socket credentials passing. */
142 /* Allows set*uid(2) manipulation (including fsuid). */
143 /* Allows forged pids on socket credentials passing. */
149 ** Linux-specific capabilities
152 /* Without VFS support for capabilities:
153 * Transfer any capability in your permitted set to any pid,
154 * remove any capability in your permitted set from any pid
155 * With VFS support for capabilities (neither of above, but)
156 * Add any capability to the current process' inheritable set
159 #define CAP_SETPCAP 8
161 /* Allow modification of S_IMMUTABLE and S_APPEND file attributes */
163 #define CAP_LINUX_IMMUTABLE 9
165 /* Allows binding to TCP/UDP sockets below 1024 */
166 /* Allows binding to ATM VCIs below 32 */
168 #define CAP_NET_BIND_SERVICE 10
170 /* Allow broadcasting, listen to multicast */
172 #define CAP_NET_BROADCAST 11
174 /* Allow interface configuration */
175 /* Allow administration of IP firewall, masquerading and accounting */
176 /* Allow setting debug option on sockets */
177 /* Allow modification of routing tables */
178 /* Allow setting arbitrary process / process group ownership on
180 /* Allow binding to any address for transparent proxying */
181 /* Allow setting TOS (type of service) */
182 /* Allow setting promiscuous mode */
183 /* Allow clearing driver statistics */
184 /* Allow multicasting */
185 /* Allow read/write of device-specific registers */
186 /* Allow activation of ATM control sockets */
188 #define CAP_NET_ADMIN 12
190 /* Allow use of RAW sockets */
191 /* Allow use of PACKET sockets */
193 #define CAP_NET_RAW 13
195 /* Allow locking of shared memory segments */
196 /* Allow mlock and mlockall (which doesn't really have anything to do
199 #define CAP_IPC_LOCK 14
201 /* Override IPC ownership checks */
203 #define CAP_IPC_OWNER 15
205 /* Insert and remove kernel modules - modify kernel without limit */
206 /* Modify cap_bset */
207 #define CAP_SYS_MODULE 16
209 /* Allow ioperm/iopl access */
210 /* Allow sending USB messages to any device via /proc/bus/usb */
212 #define CAP_SYS_RAWIO 17
214 /* Allow use of chroot() */
216 #define CAP_SYS_CHROOT 18
218 /* Allow ptrace() of any process */
220 #define CAP_SYS_PTRACE 19
222 /* Allow configuration of process accounting */
224 #define CAP_SYS_PACCT 20
226 /* Allow configuration of the secure attention key */
227 /* Allow administration of the random device */
228 /* Allow examination and configuration of disk quotas */
229 /* Allow configuring the kernel's syslog (printk behaviour) */
230 /* Allow setting the domainname */
231 /* Allow setting the hostname */
232 /* Allow calling bdflush() */
233 /* Allow mount() and umount(), setting up new smb connection */
234 /* Allow some autofs root ioctls */
235 /* Allow nfsservctl */
236 /* Allow VM86_REQUEST_IRQ */
237 /* Allow to read/write pci config on alpha */
238 /* Allow irix_prctl on mips (setstacksize) */
239 /* Allow flushing all cache on m68k (sys_cacheflush) */
240 /* Allow removing semaphores */
241 /* Used instead of CAP_CHOWN to "chown" IPC message queues, semaphores
243 /* Allow locking/unlocking of shared memory segment */
244 /* Allow turning swap on/off */
245 /* Allow forged pids on socket credentials passing */
246 /* Allow setting readahead and flushing buffers on block devices */
247 /* Allow setting geometry in floppy driver */
248 /* Allow turning DMA on/off in xd driver */
249 /* Allow administration of md devices (mostly the above, but some
251 /* Allow tuning the ide driver */
252 /* Allow access to the nvram device */
253 /* Allow administration of apm_bios, serial and bttv (TV) device */
254 /* Allow manufacturer commands in isdn CAPI support driver */
255 /* Allow reading non-standardized portions of pci configuration space */
256 /* Allow DDI debug ioctl on sbpcd driver */
257 /* Allow setting up serial ports */
258 /* Allow sending raw qic-117 commands */
259 /* Allow enabling/disabling tagged queuing on SCSI controllers and sending
260 arbitrary SCSI commands */
261 /* Allow setting encryption key on loopback filesystem */
262 /* Allow setting zone reclaim policy */
264 #define CAP_SYS_ADMIN 21
266 /* Allow use of reboot() */
268 #define CAP_SYS_BOOT 22
270 /* Allow raising priority and setting priority on other (different
272 /* Allow use of FIFO and round-robin (realtime) scheduling on own
273 processes and setting the scheduling algorithm used by another
275 /* Allow setting cpu affinity on other processes */
277 #define CAP_SYS_NICE 23
279 /* Override resource limits. Set resource limits. */
280 /* Override quota limits. */
281 /* Override reserved space on ext2 filesystem */
282 /* Modify data journaling mode on ext3 filesystem (uses journaling
284 /* NOTE: ext2 honors fsuid when checking for resource overrides, so
285 you can override using fsuid too */
286 /* Override size restrictions on IPC message queues */
287 /* Allow more than 64hz interrupts from the real-time clock */
288 /* Override max number of consoles on console allocation */
289 /* Override max number of keymaps */
291 #define CAP_SYS_RESOURCE 24
293 /* Allow manipulation of system clock */
294 /* Allow irix_stime on mips */
295 /* Allow setting the real-time clock */
297 #define CAP_SYS_TIME 25
299 /* Allow configuration of tty devices */
300 /* Allow vhangup() of tty */
302 #define CAP_SYS_TTY_CONFIG 26
304 /* Allow the privileged aspects of mknod() */
308 /* Allow taking of leases on files */
312 #define CAP_AUDIT_WRITE 29
314 #define CAP_AUDIT_CONTROL 30
316 #define CAP_SETFCAP 31
319 * Bit location of each capability (used by user-space library and kernel)
322 #define CAP_TO_INDEX(x) ((x) >> 5) /* 1 << 5 == bits in __u32 */
323 #define CAP_TO_MASK(x) (1 << ((x) & 31)) /* mask for indexed __u32 */
328 * Internal kernel functions only
331 #define CAP_FOR_EACH_U32(__capi) \
332 for (__capi = 0; __capi < _LINUX_CAPABILITY_U32S; ++__capi)
334 # define CAP_FS_MASK_B0 (CAP_TO_MASK(CAP_CHOWN) \
335 | CAP_TO_MASK(CAP_DAC_OVERRIDE) \
336 | CAP_TO_MASK(CAP_DAC_READ_SEARCH) \
337 | CAP_TO_MASK(CAP_FOWNER) \
338 | CAP_TO_MASK(CAP_FSETID))
340 #if _LINUX_CAPABILITY_U32S != 2
341 # error Fix up hand-coded capability macro initializers
342 #else /* HAND-CODED capability initializers */
344 # define CAP_EMPTY_SET {{ 0, 0 }}
345 # define CAP_FULL_SET {{ ~0, ~0 }}
346 # define CAP_INIT_EFF_SET {{ ~CAP_TO_MASK(CAP_SETPCAP), ~0 }}
347 # define CAP_FS_SET {{ CAP_FS_MASK_B0, 0 }}
348 # define CAP_NFSD_SET {{ CAP_FS_MASK_B0|CAP_TO_MASK(CAP_SYS_RESOURCE), 0 }}
350 #endif /* _LINUX_CAPABILITY_U32S != 2 */
352 #define CAP_INIT_INH_SET CAP_EMPTY_SET
354 # define cap_clear(c) do { (c) = __cap_empty_set; } while (0)
355 # define cap_set_full(c) do { (c) = __cap_full_set; } while (0)
356 # define cap_set_init_eff(c) do { (c) = __cap_init_eff_set; } while (0)
358 #define cap_raise(c, flag) ((c).cap[CAP_TO_INDEX(flag)] |= CAP_TO_MASK(flag))
359 #define cap_lower(c, flag) ((c).cap[CAP_TO_INDEX(flag)] &= ~CAP_TO_MASK(flag))
360 #define cap_raised(c, flag) ((c).cap[CAP_TO_INDEX(flag)] & CAP_TO_MASK(flag))
362 #define CAP_BOP_ALL(c, a, b, OP) \
365 CAP_FOR_EACH_U32(__capi) { \
366 c.cap[__capi] = a.cap[__capi] OP b.cap[__capi]; \
370 #define CAP_UOP_ALL(c, a, OP) \
373 CAP_FOR_EACH_U32(__capi) { \
374 c.cap[__capi] = OP a.cap[__capi]; \
378 static inline kernel_cap_t cap_combine(const kernel_cap_t a,
379 const kernel_cap_t b)
382 CAP_BOP_ALL(dest, a, b, |);
386 static inline kernel_cap_t cap_intersect(const kernel_cap_t a,
387 const kernel_cap_t b)
390 CAP_BOP_ALL(dest, a, b, &);
394 static inline kernel_cap_t cap_drop(const kernel_cap_t a,
395 const kernel_cap_t drop)
398 CAP_BOP_ALL(dest, a, drop, &~);
402 static inline kernel_cap_t cap_invert(const kernel_cap_t c)
405 CAP_UOP_ALL(dest, c, ~);
409 static inline int cap_isclear(const kernel_cap_t a)
412 CAP_FOR_EACH_U32(__capi) {
413 if (a.cap[__capi] != 0)
419 static inline int cap_issubset(const kernel_cap_t a, const kernel_cap_t set)
422 dest = cap_drop(a, set);
423 return cap_isclear(dest);
426 /* Used to decide between falling back on the old suser() or fsuser(). */
428 static inline int cap_is_fs_cap(int cap)
430 const kernel_cap_t __cap_fs_set = CAP_FS_SET;
431 return !!(CAP_TO_MASK(cap) & __cap_fs_set.cap[CAP_TO_INDEX(cap)]);
434 static inline kernel_cap_t cap_drop_fs_set(const kernel_cap_t a)
436 const kernel_cap_t __cap_fs_set = CAP_FS_SET;
437 return cap_drop(a, __cap_fs_set);
440 static inline kernel_cap_t cap_raise_fs_set(const kernel_cap_t a,
441 const kernel_cap_t permitted)
443 const kernel_cap_t __cap_fs_set = CAP_FS_SET;
444 return cap_combine(a,
445 cap_intersect(permitted, __cap_fs_set));
448 static inline kernel_cap_t cap_drop_nfsd_set(const kernel_cap_t a)
450 const kernel_cap_t __cap_fs_set = CAP_NFSD_SET;
451 return cap_drop(a, __cap_fs_set);
454 static inline kernel_cap_t cap_raise_nfsd_set(const kernel_cap_t a,
455 const kernel_cap_t permitted)
457 const kernel_cap_t __cap_nfsd_set = CAP_NFSD_SET;
458 return cap_combine(a,
459 cap_intersect(permitted, __cap_nfsd_set));
462 extern const kernel_cap_t __cap_empty_set;
463 extern const kernel_cap_t __cap_full_set;
464 extern const kernel_cap_t __cap_init_eff_set;
466 int capable(int cap);
467 int __capable(struct task_struct *t, int cap);
469 #endif /* __KERNEL__ */
471 #endif /* !_LINUX_CAPABILITY_H */