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1/*
2 * This is <linux/capability.h>
3 *
4 * Andrew G. Morgan <morgan@kernel.org>
5 * Alexander Kjeldaas <astor@guardian.no>
6 * with help from Aleph1, Roland Buresund and Andrew Main.
7 *
8 * See here for the libcap library ("POSIX draft" compliance):
9 *
10 * ftp://linux.kernel.org/pub/linux/libs/security/linux-privs/kernel-2.6/
11 */
12
13#ifndef _LINUX_CAPABILITY_H
14#define _LINUX_CAPABILITY_H
15
16#include <linux/types.h>
17
18struct task_struct;
19
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
23 it. */
24
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
29 etc.. */
30
31#define _LINUX_CAPABILITY_VERSION_1 0x19980330
32#define _LINUX_CAPABILITY_U32S_1 1
33
34#define _LINUX_CAPABILITY_VERSION_2 0x20071026 /* deprecated - use v3 */
35#define _LINUX_CAPABILITY_U32S_2 2
36
37#define _LINUX_CAPABILITY_VERSION_3 0x20080522
38#define _LINUX_CAPABILITY_U32S_3 2
39
40typedef struct __user_cap_header_struct {
41 __u32 version;
42 int pid;
43} __user *cap_user_header_t;
44
45typedef struct __user_cap_data_struct {
46 __u32 effective;
47 __u32 permitted;
48 __u32 inheritable;
49} __user *cap_user_data_t;
50
51
52#define XATTR_CAPS_SUFFIX "capability"
53#define XATTR_NAME_CAPS XATTR_SECURITY_PREFIX XATTR_CAPS_SUFFIX
54
55#define VFS_CAP_REVISION_MASK 0xFF000000
56#define VFS_CAP_FLAGS_MASK ~VFS_CAP_REVISION_MASK
57#define VFS_CAP_FLAGS_EFFECTIVE 0x000001
58
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))
62
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))
66
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
70
71
72struct vfs_cap_data {
73 __le32 magic_etc; /* Little endian */
74 struct {
75 __le32 permitted; /* Little endian */
76 __le32 inheritable; /* Little endian */
77 } data[VFS_CAP_U32];
78};
79
80#ifndef __KERNEL__
81
82/*
83 * Backwardly compatible definition for source code - trapped in a
84 * 32-bit world. If you find you need this, please consider using
85 * libcap to untrap yourself...
86 */
87#define _LINUX_CAPABILITY_VERSION _LINUX_CAPABILITY_VERSION_1
88#define _LINUX_CAPABILITY_U32S _LINUX_CAPABILITY_U32S_1
89
90#else
91
92#define _KERNEL_CAPABILITY_VERSION _LINUX_CAPABILITY_VERSION_3
93#define _KERNEL_CAPABILITY_U32S _LINUX_CAPABILITY_U32S_3
94
95typedef struct kernel_cap_struct {
96 __u32 cap[_KERNEL_CAPABILITY_U32S];
97} kernel_cap_t;
98
99#define _USER_CAP_HEADER_SIZE (sizeof(struct __user_cap_header_struct))
100#define _KERNEL_CAP_T_SIZE (sizeof(kernel_cap_t))
101
102#endif
103
104
105/**
106 ** POSIX-draft defined capabilities.
107 **/
108
109/* In a system with the [_POSIX_CHOWN_RESTRICTED] option defined, this
110 overrides the restriction of changing file ownership and group
111 ownership. */
112
113#define CAP_CHOWN 0
114
115/* Override all DAC access, including ACL execute access if
116 [_POSIX_ACL] is defined. Excluding DAC access covered by
117 CAP_LINUX_IMMUTABLE. */
118
119#define CAP_DAC_OVERRIDE 1
120
121/* Overrides all DAC restrictions regarding read and search on files
122 and directories, including ACL restrictions if [_POSIX_ACL] is
123 defined. Excluding DAC access covered by CAP_LINUX_IMMUTABLE. */
124
125#define CAP_DAC_READ_SEARCH 2
126
127/* Overrides all restrictions about allowed operations on files, where
128 file owner ID must be equal to the user ID, except where CAP_FSETID
129 is applicable. It doesn't override MAC and DAC restrictions. */
130
131#define CAP_FOWNER 3
132
133/* Overrides the following restrictions that the effective user ID
134 shall match the file owner ID when setting the S_ISUID and S_ISGID
135 bits on that file; that the effective group ID (or one of the
136 supplementary group IDs) shall match the file owner ID when setting
137 the S_ISGID bit on that file; that the S_ISUID and S_ISGID bits are
138 cleared on successful return from chown(2) (not implemented). */
139
140#define CAP_FSETID 4
141
142/* Overrides the restriction that the real or effective user ID of a
143 process sending a signal must match the real or effective user ID
144 of the process receiving the signal. */
145
146#define CAP_KILL 5
147
148/* Allows setgid(2) manipulation */
149/* Allows setgroups(2) */
150/* Allows forged gids on socket credentials passing. */
151
152#define CAP_SETGID 6
153
154/* Allows set*uid(2) manipulation (including fsuid). */
155/* Allows forged pids on socket credentials passing. */
156
157#define CAP_SETUID 7
158
159
160/**
161 ** Linux-specific capabilities
162 **/
163
164/* Without VFS support for capabilities:
165 * Transfer any capability in your permitted set to any pid,
166 * remove any capability in your permitted set from any pid
167 * With VFS support for capabilities (neither of above, but)
168 * Add any capability from current's capability bounding set
169 * to the current process' inheritable set
170 * Allow taking bits out of capability bounding set
171 * Allow modification of the securebits for a process
172 */
173
174#define CAP_SETPCAP 8
175
176/* Allow modification of S_IMMUTABLE and S_APPEND file attributes */
177
178#define CAP_LINUX_IMMUTABLE 9
179
180/* Allows binding to TCP/UDP sockets below 1024 */
181/* Allows binding to ATM VCIs below 32 */
182
183#define CAP_NET_BIND_SERVICE 10
184
185/* Allow broadcasting, listen to multicast */
186
187#define CAP_NET_BROADCAST 11
188
189/* Allow interface configuration */
190/* Allow administration of IP firewall, masquerading and accounting */
191/* Allow setting debug option on sockets */
192/* Allow modification of routing tables */
193/* Allow setting arbitrary process / process group ownership on
194 sockets */
195/* Allow binding to any address for transparent proxying */
196/* Allow setting TOS (type of service) */
197/* Allow setting promiscuous mode */
198/* Allow clearing driver statistics */
199/* Allow multicasting */
200/* Allow read/write of device-specific registers */
201/* Allow activation of ATM control sockets */
202
203#define CAP_NET_ADMIN 12
204
205/* Allow use of RAW sockets */
206/* Allow use of PACKET sockets */
207
208#define CAP_NET_RAW 13
209
210/* Allow locking of shared memory segments */
211/* Allow mlock and mlockall (which doesn't really have anything to do
212 with IPC) */
213
214#define CAP_IPC_LOCK 14
215
216/* Override IPC ownership checks */
217
218#define CAP_IPC_OWNER 15
219
220/* Insert and remove kernel modules - modify kernel without limit */
221#define CAP_SYS_MODULE 16
222
223/* Allow ioperm/iopl access */
224/* Allow sending USB messages to any device via /proc/bus/usb */
225
226#define CAP_SYS_RAWIO 17
227
228/* Allow use of chroot() */
229
230#define CAP_SYS_CHROOT 18
231
232/* Allow ptrace() of any process */
233
234#define CAP_SYS_PTRACE 19
235
236/* Allow configuration of process accounting */
237
238#define CAP_SYS_PACCT 20
239
240/* Allow configuration of the secure attention key */
241/* Allow administration of the random device */
242/* Allow examination and configuration of disk quotas */
243/* Allow configuring the kernel's syslog (printk behaviour) */
244/* Allow setting the domainname */
245/* Allow setting the hostname */
246/* Allow calling bdflush() */
247/* Allow mount() and umount(), setting up new smb connection */
248/* Allow some autofs root ioctls */
249/* Allow nfsservctl */
250/* Allow VM86_REQUEST_IRQ */
251/* Allow to read/write pci config on alpha */
252/* Allow irix_prctl on mips (setstacksize) */
253/* Allow flushing all cache on m68k (sys_cacheflush) */
254/* Allow removing semaphores */
255/* Used instead of CAP_CHOWN to "chown" IPC message queues, semaphores
256 and shared memory */
257/* Allow locking/unlocking of shared memory segment */
258/* Allow turning swap on/off */
259/* Allow forged pids on socket credentials passing */
260/* Allow setting readahead and flushing buffers on block devices */
261/* Allow setting geometry in floppy driver */
262/* Allow turning DMA on/off in xd driver */
263/* Allow administration of md devices (mostly the above, but some
264 extra ioctls) */
265/* Allow tuning the ide driver */
266/* Allow access to the nvram device */
267/* Allow administration of apm_bios, serial and bttv (TV) device */
268/* Allow manufacturer commands in isdn CAPI support driver */
269/* Allow reading non-standardized portions of pci configuration space */
270/* Allow DDI debug ioctl on sbpcd driver */
271/* Allow setting up serial ports */
272/* Allow sending raw qic-117 commands */
273/* Allow enabling/disabling tagged queuing on SCSI controllers and sending
274 arbitrary SCSI commands */
275/* Allow setting encryption key on loopback filesystem */
276/* Allow setting zone reclaim policy */
277
278#define CAP_SYS_ADMIN 21
279
280/* Allow use of reboot() */
281
282#define CAP_SYS_BOOT 22
283
284/* Allow raising priority and setting priority on other (different
285 UID) processes */
286/* Allow use of FIFO and round-robin (realtime) scheduling on own
287 processes and setting the scheduling algorithm used by another
288 process. */
289/* Allow setting cpu affinity on other processes */
290
291#define CAP_SYS_NICE 23
292
293/* Override resource limits. Set resource limits. */
294/* Override quota limits. */
295/* Override reserved space on ext2 filesystem */
296/* Modify data journaling mode on ext3 filesystem (uses journaling
297 resources) */
298/* NOTE: ext2 honors fsuid when checking for resource overrides, so
299 you can override using fsuid too */
300/* Override size restrictions on IPC message queues */
301/* Allow more than 64hz interrupts from the real-time clock */
302/* Override max number of consoles on console allocation */
303/* Override max number of keymaps */
304
305#define CAP_SYS_RESOURCE 24
306
307/* Allow manipulation of system clock */
308/* Allow irix_stime on mips */
309/* Allow setting the real-time clock */
310
311#define CAP_SYS_TIME 25
312
313/* Allow configuration of tty devices */
314/* Allow vhangup() of tty */
315
316#define CAP_SYS_TTY_CONFIG 26
317
318/* Allow the privileged aspects of mknod() */
319
320#define CAP_MKNOD 27
321
322/* Allow taking of leases on files */
323
324#define CAP_LEASE 28
325
326#define CAP_AUDIT_WRITE 29
327
328#define CAP_AUDIT_CONTROL 30
329
330#define CAP_SETFCAP 31
331
332/* Override MAC access.
333 The base kernel enforces no MAC policy.
334 An LSM may enforce a MAC policy, and if it does and it chooses
335 to implement capability based overrides of that policy, this is
336 the capability it should use to do so. */
337
338#define CAP_MAC_OVERRIDE 32
339
340/* Allow MAC configuration or state changes.
341 The base kernel requires no MAC configuration.
342 An LSM may enforce a MAC policy, and if it does and it chooses
343 to implement capability based checks on modifications to that
344 policy or the data required to maintain it, this is the
345 capability it should use to do so. */
346
347#define CAP_MAC_ADMIN 33
348
349#define CAP_LAST_CAP CAP_MAC_ADMIN
350
351#define cap_valid(x) ((x) >= 0 && (x) <= CAP_LAST_CAP)
352
353/*
354 * Bit location of each capability (used by user-space library and kernel)
355 */
356
357#define CAP_TO_INDEX(x) ((x) >> 5) /* 1 << 5 == bits in __u32 */
358#define CAP_TO_MASK(x) (1 << ((x) & 31)) /* mask for indexed __u32 */
359
360#ifdef __KERNEL__
361
362/*
363 * Internal kernel functions only
364 */
365
366#define CAP_FOR_EACH_U32(__capi) \
367 for (__capi = 0; __capi < _KERNEL_CAPABILITY_U32S; ++__capi)
368
369# define CAP_FS_MASK_B0 (CAP_TO_MASK(CAP_CHOWN) \
370 | CAP_TO_MASK(CAP_DAC_OVERRIDE) \
371 | CAP_TO_MASK(CAP_DAC_READ_SEARCH) \
372 | CAP_TO_MASK(CAP_FOWNER) \
373 | CAP_TO_MASK(CAP_FSETID))
374
375# define CAP_FS_MASK_B1 (CAP_TO_MASK(CAP_MAC_OVERRIDE))
376
377#if _KERNEL_CAPABILITY_U32S != 2
378# error Fix up hand-coded capability macro initializers
379#else /* HAND-CODED capability initializers */
380
381# define CAP_EMPTY_SET ((kernel_cap_t){{ 0, 0 }})
382# define CAP_FULL_SET ((kernel_cap_t){{ ~0, ~0 }})
383# define CAP_INIT_EFF_SET ((kernel_cap_t){{ ~CAP_TO_MASK(CAP_SETPCAP), ~0 }})
384# define CAP_FS_SET ((kernel_cap_t){{ CAP_FS_MASK_B0, CAP_FS_MASK_B1 } })
385# define CAP_NFSD_SET ((kernel_cap_t){{ CAP_FS_MASK_B0|CAP_TO_MASK(CAP_SYS_RESOURCE), \
386 CAP_FS_MASK_B1 } })
387
388#endif /* _KERNEL_CAPABILITY_U32S != 2 */
389
390#define CAP_INIT_INH_SET CAP_EMPTY_SET
391
392# define cap_clear(c) do { (c) = __cap_empty_set; } while (0)
393# define cap_set_full(c) do { (c) = __cap_full_set; } while (0)
394# define cap_set_init_eff(c) do { (c) = __cap_init_eff_set; } while (0)
395
396#define cap_raise(c, flag) ((c).cap[CAP_TO_INDEX(flag)] |= CAP_TO_MASK(flag))
397#define cap_lower(c, flag) ((c).cap[CAP_TO_INDEX(flag)] &= ~CAP_TO_MASK(flag))
398#define cap_raised(c, flag) ((c).cap[CAP_TO_INDEX(flag)] & CAP_TO_MASK(flag))
399
400#define CAP_BOP_ALL(c, a, b, OP) \
401do { \
402 unsigned __capi; \
403 CAP_FOR_EACH_U32(__capi) { \
404 c.cap[__capi] = a.cap[__capi] OP b.cap[__capi]; \
405 } \
406} while (0)
407
408#define CAP_UOP_ALL(c, a, OP) \
409do { \
410 unsigned __capi; \
411 CAP_FOR_EACH_U32(__capi) { \
412 c.cap[__capi] = OP a.cap[__capi]; \
413 } \
414} while (0)
415
416static inline kernel_cap_t cap_combine(const kernel_cap_t a,
417 const kernel_cap_t b)
418{
419 kernel_cap_t dest;
420 CAP_BOP_ALL(dest, a, b, |);
421 return dest;
422}
423
424static inline kernel_cap_t cap_intersect(const kernel_cap_t a,
425 const kernel_cap_t b)
426{
427 kernel_cap_t dest;
428 CAP_BOP_ALL(dest, a, b, &);
429 return dest;
430}
431
432static inline kernel_cap_t cap_drop(const kernel_cap_t a,
433 const kernel_cap_t drop)
434{
435 kernel_cap_t dest;
436 CAP_BOP_ALL(dest, a, drop, &~);
437 return dest;
438}
439
440static inline kernel_cap_t cap_invert(const kernel_cap_t c)
441{
442 kernel_cap_t dest;
443 CAP_UOP_ALL(dest, c, ~);
444 return dest;
445}
446
447static inline int cap_isclear(const kernel_cap_t a)
448{
449 unsigned __capi;
450 CAP_FOR_EACH_U32(__capi) {
451 if (a.cap[__capi] != 0)
452 return 0;
453 }
454 return 1;
455}
456
457static inline int cap_issubset(const kernel_cap_t a, const kernel_cap_t set)
458{
459 kernel_cap_t dest;
460 dest = cap_drop(a, set);
461 return cap_isclear(dest);
462}
463
464/* Used to decide between falling back on the old suser() or fsuser(). */
465
466static inline int cap_is_fs_cap(int cap)
467{
468 const kernel_cap_t __cap_fs_set = CAP_FS_SET;
469 return !!(CAP_TO_MASK(cap) & __cap_fs_set.cap[CAP_TO_INDEX(cap)]);
470}
471
472static inline kernel_cap_t cap_drop_fs_set(const kernel_cap_t a)
473{
474 const kernel_cap_t __cap_fs_set = CAP_FS_SET;
475 return cap_drop(a, __cap_fs_set);
476}
477
478static inline kernel_cap_t cap_raise_fs_set(const kernel_cap_t a,
479 const kernel_cap_t permitted)
480{
481 const kernel_cap_t __cap_fs_set = CAP_FS_SET;
482 return cap_combine(a,
483 cap_intersect(permitted, __cap_fs_set));
484}
485
486static inline kernel_cap_t cap_drop_nfsd_set(const kernel_cap_t a)
487{
488 const kernel_cap_t __cap_fs_set = CAP_NFSD_SET;
489 return cap_drop(a, __cap_fs_set);
490}
491
492static inline kernel_cap_t cap_raise_nfsd_set(const kernel_cap_t a,
493 const kernel_cap_t permitted)
494{
495 const kernel_cap_t __cap_nfsd_set = CAP_NFSD_SET;
496 return cap_combine(a,
497 cap_intersect(permitted, __cap_nfsd_set));
498}
499
500extern const kernel_cap_t __cap_empty_set;
501extern const kernel_cap_t __cap_full_set;
502extern const kernel_cap_t __cap_init_eff_set;
503
504kernel_cap_t cap_set_effective(const kernel_cap_t pE_new);
505
506/**
507 * has_capability - Determine if a task has a superior capability available
508 * @t: The task in question
509 * @cap: The capability to be tested for
510 *
511 * Return true if the specified task has the given superior capability
512 * currently in effect, false if not.
513 *
514 * Note that this does not set PF_SUPERPRIV on the task.
515 */
516#define has_capability(t, cap) (security_capable((t), (cap)) == 0)
517
518extern int capable(int cap);
519
520#endif /* __KERNEL__ */
521
522#endif /* !_LINUX_CAPABILITY_H */