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 35 #define _LINUX_CAPABILITY_U32S_2 2 36 37 #define _LINUX_CAPABILITY_VERSION _LINUX_CAPABILITY_VERSION_2 38 #define _LINUX_CAPABILITY_U32S _LINUX_CAPABILITY_U32S_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 #ifdef __KERNEL__ 81 82 typedef struct kernel_cap_struct { 83 __u32 cap[_LINUX_CAPABILITY_U32S]; 84 } kernel_cap_t; 85 86 #define _USER_CAP_HEADER_SIZE (sizeof(struct __user_cap_header_struct)) 87 #define _KERNEL_CAP_T_SIZE (sizeof(kernel_cap_t)) 88 89 #endif 90 91 92 /** 93 ** POSIX-draft defined capabilities. 94 **/ 95 96 /* In a system with the [_POSIX_CHOWN_RESTRICTED] option defined, this 97 overrides the restriction of changing file ownership and group 98 ownership. */ 99 100 #define CAP_CHOWN 0 101 102 /* Override all DAC access, including ACL execute access if 103 [_POSIX_ACL] is defined. Excluding DAC access covered by 104 CAP_LINUX_IMMUTABLE. */ 105 106 #define CAP_DAC_OVERRIDE 1 107 108 /* Overrides all DAC restrictions regarding read and search on files 109 and directories, including ACL restrictions if [_POSIX_ACL] is 110 defined. Excluding DAC access covered by CAP_LINUX_IMMUTABLE. */ 111 112 #define CAP_DAC_READ_SEARCH 2 113 114 /* Overrides all restrictions about allowed operations on files, where 115 file owner ID must be equal to the user ID, except where CAP_FSETID 116 is applicable. It doesn't override MAC and DAC restrictions. */ 117 118 #define CAP_FOWNER 3 119 120 /* Overrides the following restrictions that the effective user ID 121 shall match the file owner ID when setting the S_ISUID and S_ISGID 122 bits on that file; that the effective group ID (or one of the 123 supplementary group IDs) shall match the file owner ID when setting 124 the S_ISGID bit on that file; that the S_ISUID and S_ISGID bits are 125 cleared on successful return from chown(2) (not implemented). */ 126 127 #define CAP_FSETID 4 128 129 /* Overrides the restriction that the real or effective user ID of a 130 process sending a signal must match the real or effective user ID 131 of the process receiving the signal. */ 132 133 #define CAP_KILL 5 134 135 /* Allows setgid(2) manipulation */ 136 /* Allows setgroups(2) */ 137 /* Allows forged gids on socket credentials passing. */ 138 139 #define CAP_SETGID 6 140 141 /* Allows set*uid(2) manipulation (including fsuid). */ 142 /* Allows forged pids on socket credentials passing. */ 143 144 #define CAP_SETUID 7 145 146 147 /** 148 ** Linux-specific capabilities 149 **/ 150 151 /* Without VFS support for capabilities: 152 * Transfer any capability in your permitted set to any pid, 153 * remove any capability in your permitted set from any pid 154 * With VFS support for capabilities (neither of above, but) 155 * Add any capability from current's capability bounding set 156 * to the current process' inheritable set 157 * Allow taking bits out of capability bounding set 158 */ 159 160 #define CAP_SETPCAP 8 161 162 /* Allow modification of S_IMMUTABLE and S_APPEND file attributes */ 163 164 #define CAP_LINUX_IMMUTABLE 9 165 166 /* Allows binding to TCP/UDP sockets below 1024 */ 167 /* Allows binding to ATM VCIs below 32 */ 168 169 #define CAP_NET_BIND_SERVICE 10 170 171 /* Allow broadcasting, listen to multicast */ 172 173 #define CAP_NET_BROADCAST 11 174 175 /* Allow interface configuration */ 176 /* Allow administration of IP firewall, masquerading and accounting */ 177 /* Allow setting debug option on sockets */ 178 /* Allow modification of routing tables */ 179 /* Allow setting arbitrary process / process group ownership on 180 sockets */ 181 /* Allow binding to any address for transparent proxying */ 182 /* Allow setting TOS (type of service) */ 183 /* Allow setting promiscuous mode */ 184 /* Allow clearing driver statistics */ 185 /* Allow multicasting */ 186 /* Allow read/write of device-specific registers */ 187 /* Allow activation of ATM control sockets */ 188 189 #define CAP_NET_ADMIN 12 190 191 /* Allow use of RAW sockets */ 192 /* Allow use of PACKET sockets */ 193 194 #define CAP_NET_RAW 13 195 196 /* Allow locking of shared memory segments */ 197 /* Allow mlock and mlockall (which doesn't really have anything to do 198 with IPC) */ 199 200 #define CAP_IPC_LOCK 14 201 202 /* Override IPC ownership checks */ 203 204 #define CAP_IPC_OWNER 15 205 206 /* Insert and remove kernel modules - modify kernel without limit */ 207 #define CAP_SYS_MODULE 16 208 209 /* Allow ioperm/iopl access */ 210 /* Allow sending USB messages to any device via /proc/bus/usb */ 211 212 #define CAP_SYS_RAWIO 17 213 214 /* Allow use of chroot() */ 215 216 #define CAP_SYS_CHROOT 18 217 218 /* Allow ptrace() of any process */ 219 220 #define CAP_SYS_PTRACE 19 221 222 /* Allow configuration of process accounting */ 223 224 #define CAP_SYS_PACCT 20 225 226 /* 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 242 and shared memory */ 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 250 extra ioctls) */ 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 */ 263 264 #define CAP_SYS_ADMIN 21 265 266 /* Allow use of reboot() */ 267 268 #define CAP_SYS_BOOT 22 269 270 /* Allow raising priority and setting priority on other (different 271 UID) processes */ 272 /* Allow use of FIFO and round-robin (realtime) scheduling on own 273 processes and setting the scheduling algorithm used by another 274 process. */ 275 /* Allow setting cpu affinity on other processes */ 276 277 #define CAP_SYS_NICE 23 278 279 /* 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 283 resources) */ 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 */ 290 291 #define CAP_SYS_RESOURCE 24 292 293 /* Allow manipulation of system clock */ 294 /* Allow irix_stime on mips */ 295 /* Allow setting the real-time clock */ 296 297 #define CAP_SYS_TIME 25 298 299 /* Allow configuration of tty devices */ 300 /* Allow vhangup() of tty */ 301 302 #define CAP_SYS_TTY_CONFIG 26 303 304 /* Allow the privileged aspects of mknod() */ 305 306 #define CAP_MKNOD 27 307 308 /* Allow taking of leases on files */ 309 310 #define CAP_LEASE 28 311 312 #define CAP_AUDIT_WRITE 29 313 314 #define CAP_AUDIT_CONTROL 30 315 316 #define CAP_SETFCAP 31 317 318 /* Override MAC access. 319 The base kernel enforces no MAC policy. 320 An LSM may enforce a MAC policy, and if it does and it chooses 321 to implement capability based overrides of that policy, this is 322 the capability it should use to do so. */ 323 324 #define CAP_MAC_OVERRIDE 32 325 326 /* Allow MAC configuration or state changes. 327 The base kernel requires no MAC configuration. 328 An LSM may enforce a MAC policy, and if it does and it chooses 329 to implement capability based checks on modifications to that 330 policy or the data required to maintain it, this is the 331 capability it should use to do so. */ 332 333 #define CAP_MAC_ADMIN 33 334 335 #define CAP_LAST_CAP CAP_MAC_ADMIN 336 337 #define cap_valid(x) ((x) >= 0 && (x) <= CAP_LAST_CAP) 338 339 /* 340 * Bit location of each capability (used by user-space library and kernel) 341 */ 342 343 #define CAP_TO_INDEX(x) ((x) >> 5) /* 1 << 5 == bits in __u32 */ 344 #define CAP_TO_MASK(x) (1 << ((x) & 31)) /* mask for indexed __u32 */ 345 346 #ifdef __KERNEL__ 347 348 /* 349 * Internal kernel functions only 350 */ 351 352 #define CAP_FOR_EACH_U32(__capi) \ 353 for (__capi = 0; __capi < _LINUX_CAPABILITY_U32S; ++__capi) 354 355 # define CAP_FS_MASK_B0 (CAP_TO_MASK(CAP_CHOWN) \ 356 | CAP_TO_MASK(CAP_DAC_OVERRIDE) \ 357 | CAP_TO_MASK(CAP_DAC_READ_SEARCH) \ 358 | CAP_TO_MASK(CAP_FOWNER) \ 359 | CAP_TO_MASK(CAP_FSETID)) 360 361 # define CAP_FS_MASK_B1 (CAP_TO_MASK(CAP_MAC_OVERRIDE)) 362 363 #if _LINUX_CAPABILITY_U32S != 2 364 # error Fix up hand-coded capability macro initializers 365 #else /* HAND-CODED capability initializers */ 366 367 # define CAP_EMPTY_SET {{ 0, 0 }} 368 # define CAP_FULL_SET {{ ~0, ~0 }} 369 # define CAP_INIT_EFF_SET {{ ~CAP_TO_MASK(CAP_SETPCAP), ~0 }} 370 # define CAP_FS_SET {{ CAP_FS_MASK_B0, CAP_FS_MASK_B1 } } 371 # define CAP_NFSD_SET {{ CAP_FS_MASK_B0|CAP_TO_MASK(CAP_SYS_RESOURCE), \ 372 CAP_FS_MASK_B1 } } 373 374 #endif /* _LINUX_CAPABILITY_U32S != 2 */ 375 376 #define CAP_INIT_INH_SET CAP_EMPTY_SET 377 378 # define cap_clear(c) do { (c) = __cap_empty_set; } while (0) 379 # define cap_set_full(c) do { (c) = __cap_full_set; } while (0) 380 # define cap_set_init_eff(c) do { (c) = __cap_init_eff_set; } while (0) 381 382 #define cap_raise(c, flag) ((c).cap[CAP_TO_INDEX(flag)] |= CAP_TO_MASK(flag)) 383 #define cap_lower(c, flag) ((c).cap[CAP_TO_INDEX(flag)] &= ~CAP_TO_MASK(flag)) 384 #define cap_raised(c, flag) ((c).cap[CAP_TO_INDEX(flag)] & CAP_TO_MASK(flag)) 385 386 #define CAP_BOP_ALL(c, a, b, OP) \ 387 do { \ 388 unsigned __capi; \ 389 CAP_FOR_EACH_U32(__capi) { \ 390 c.cap[__capi] = a.cap[__capi] OP b.cap[__capi]; \ 391 } \ 392 } while (0) 393 394 #define CAP_UOP_ALL(c, a, OP) \ 395 do { \ 396 unsigned __capi; \ 397 CAP_FOR_EACH_U32(__capi) { \ 398 c.cap[__capi] = OP a.cap[__capi]; \ 399 } \ 400 } while (0) 401 402 static inline kernel_cap_t cap_combine(const kernel_cap_t a, 403 const kernel_cap_t b) 404 { 405 kernel_cap_t dest; 406 CAP_BOP_ALL(dest, a, b, |); 407 return dest; 408 } 409 410 static inline kernel_cap_t cap_intersect(const kernel_cap_t a, 411 const kernel_cap_t b) 412 { 413 kernel_cap_t dest; 414 CAP_BOP_ALL(dest, a, b, &); 415 return dest; 416 } 417 418 static inline kernel_cap_t cap_drop(const kernel_cap_t a, 419 const kernel_cap_t drop) 420 { 421 kernel_cap_t dest; 422 CAP_BOP_ALL(dest, a, drop, &~); 423 return dest; 424 } 425 426 static inline kernel_cap_t cap_invert(const kernel_cap_t c) 427 { 428 kernel_cap_t dest; 429 CAP_UOP_ALL(dest, c, ~); 430 return dest; 431 } 432 433 static inline int cap_isclear(const kernel_cap_t a) 434 { 435 unsigned __capi; 436 CAP_FOR_EACH_U32(__capi) { 437 if (a.cap[__capi] != 0) 438 return 0; 439 } 440 return 1; 441 } 442 443 static inline int cap_issubset(const kernel_cap_t a, const kernel_cap_t set) 444 { 445 kernel_cap_t dest; 446 dest = cap_drop(a, set); 447 return cap_isclear(dest); 448 } 449 450 /* Used to decide between falling back on the old suser() or fsuser(). */ 451 452 static inline int cap_is_fs_cap(int cap) 453 { 454 const kernel_cap_t __cap_fs_set = CAP_FS_SET; 455 return !!(CAP_TO_MASK(cap) & __cap_fs_set.cap[CAP_TO_INDEX(cap)]); 456 } 457 458 static inline kernel_cap_t cap_drop_fs_set(const kernel_cap_t a) 459 { 460 const kernel_cap_t __cap_fs_set = CAP_FS_SET; 461 return cap_drop(a, __cap_fs_set); 462 } 463 464 static inline kernel_cap_t cap_raise_fs_set(const kernel_cap_t a, 465 const kernel_cap_t permitted) 466 { 467 const kernel_cap_t __cap_fs_set = CAP_FS_SET; 468 return cap_combine(a, 469 cap_intersect(permitted, __cap_fs_set)); 470 } 471 472 static inline kernel_cap_t cap_drop_nfsd_set(const kernel_cap_t a) 473 { 474 const kernel_cap_t __cap_fs_set = CAP_NFSD_SET; 475 return cap_drop(a, __cap_fs_set); 476 } 477 478 static inline kernel_cap_t cap_raise_nfsd_set(const kernel_cap_t a, 479 const kernel_cap_t permitted) 480 { 481 const kernel_cap_t __cap_nfsd_set = CAP_NFSD_SET; 482 return cap_combine(a, 483 cap_intersect(permitted, __cap_nfsd_set)); 484 } 485 486 extern const kernel_cap_t __cap_empty_set; 487 extern const kernel_cap_t __cap_full_set; 488 extern const kernel_cap_t __cap_init_eff_set; 489 490 int capable(int cap); 491 int __capable(struct task_struct *t, int cap); 492 493 extern long cap_prctl_drop(unsigned long cap); 494 495 #endif /* __KERNEL__ */ 496 497 #endif /* !_LINUX_CAPABILITY_H */ 498