1 /* 2 * This is <linux/capability.h> 3 * 4 * Andrew G. Morgan <[email protected]> 5 * Alexander Kjeldaas <[email protected]> 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 18 struct 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 40 typedef struct __user_cap_header_struct { 41 __u32 version; 42 int pid; 43 } __user *cap_user_header_t; 44 45 typedef 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 72 struct 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 95 typedef 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) \ 401 do { \ 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) \ 409 do { \ 410 unsigned __capi; \ 411 CAP_FOR_EACH_U32(__capi) { \ 412 c.cap[__capi] = OP a.cap[__capi]; \ 413 } \ 414 } while (0) 415 416 static 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 } 423 424 static 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 } 431 432 static 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 } 439 440 static 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 } 446 447 static 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 } 456 457 static 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(). */ 465 466 static 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 } 471 472 static 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 } 477 478 static 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 } 485 486 static 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 } 491 492 static 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 } 499 500 extern const kernel_cap_t __cap_empty_set; 501 extern const kernel_cap_t __cap_full_set; 502 extern const kernel_cap_t __cap_init_eff_set; 503 504 kernel_cap_t cap_set_effective(const kernel_cap_t pE_new); 505 506 int capable(int cap); 507 int __capable(struct task_struct *t, int cap); 508 509 #endif /* __KERNEL__ */ 510 511 #endif /* !_LINUX_CAPABILITY_H */ 512