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://www.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_REVISION_SHIFT 24 57#define VFS_CAP_FLAGS_MASK ~VFS_CAP_REVISION_MASK 58#define VFS_CAP_FLAGS_EFFECTIVE 0x000001 59 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)) 63 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)) 67 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 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 95#ifdef CONFIG_SECURITY_FILE_CAPABILITIES 96extern int file_caps_enabled; 97#endif 98 99typedef struct kernel_cap_struct { 100 __u32 cap[_KERNEL_CAPABILITY_U32S]; 101} kernel_cap_t; 102 103/* exact same as vfs_cap_data but in cpu endian and always filled completely */ 104struct cpu_vfs_cap_data { 105 __u32 magic_etc; 106 kernel_cap_t permitted; 107 kernel_cap_t inheritable; 108}; 109 110#define _USER_CAP_HEADER_SIZE (sizeof(struct __user_cap_header_struct)) 111#define _KERNEL_CAP_T_SIZE (sizeof(kernel_cap_t)) 112 113#endif 114 115 116/** 117 ** POSIX-draft defined capabilities. 118 **/ 119 120/* In a system with the [_POSIX_CHOWN_RESTRICTED] option defined, this 121 overrides the restriction of changing file ownership and group 122 ownership. */ 123 124#define CAP_CHOWN 0 125 126/* Override all DAC access, including ACL execute access if 127 [_POSIX_ACL] is defined. Excluding DAC access covered by 128 CAP_LINUX_IMMUTABLE. */ 129 130#define CAP_DAC_OVERRIDE 1 131 132/* Overrides all DAC restrictions regarding read and search on files 133 and directories, including ACL restrictions if [_POSIX_ACL] is 134 defined. Excluding DAC access covered by CAP_LINUX_IMMUTABLE. */ 135 136#define CAP_DAC_READ_SEARCH 2 137 138/* Overrides all restrictions about allowed operations on files, where 139 file owner ID must be equal to the user ID, except where CAP_FSETID 140 is applicable. It doesn't override MAC and DAC restrictions. */ 141 142#define CAP_FOWNER 3 143 144/* Overrides the following restrictions that the effective user ID 145 shall match the file owner ID when setting the S_ISUID and S_ISGID 146 bits on that file; that the effective group ID (or one of the 147 supplementary group IDs) shall match the file owner ID when setting 148 the S_ISGID bit on that file; that the S_ISUID and S_ISGID bits are 149 cleared on successful return from chown(2) (not implemented). */ 150 151#define CAP_FSETID 4 152 153/* Overrides the restriction that the real or effective user ID of a 154 process sending a signal must match the real or effective user ID 155 of the process receiving the signal. */ 156 157#define CAP_KILL 5 158 159/* Allows setgid(2) manipulation */ 160/* Allows setgroups(2) */ 161/* Allows forged gids on socket credentials passing. */ 162 163#define CAP_SETGID 6 164 165/* Allows set*uid(2) manipulation (including fsuid). */ 166/* Allows forged pids on socket credentials passing. */ 167 168#define CAP_SETUID 7 169 170 171/** 172 ** Linux-specific capabilities 173 **/ 174 175/* Without VFS support for capabilities: 176 * Transfer any capability in your permitted set to any pid, 177 * remove any capability in your permitted set from any pid 178 * With VFS support for capabilities (neither of above, but) 179 * Add any capability from current's capability bounding set 180 * to the current process' inheritable set 181 * Allow taking bits out of capability bounding set 182 * Allow modification of the securebits for a process 183 */ 184 185#define CAP_SETPCAP 8 186 187/* Allow modification of S_IMMUTABLE and S_APPEND file attributes */ 188 189#define CAP_LINUX_IMMUTABLE 9 190 191/* Allows binding to TCP/UDP sockets below 1024 */ 192/* Allows binding to ATM VCIs below 32 */ 193 194#define CAP_NET_BIND_SERVICE 10 195 196/* Allow broadcasting, listen to multicast */ 197 198#define CAP_NET_BROADCAST 11 199 200/* Allow interface configuration */ 201/* Allow administration of IP firewall, masquerading and accounting */ 202/* Allow setting debug option on sockets */ 203/* Allow modification of routing tables */ 204/* Allow setting arbitrary process / process group ownership on 205 sockets */ 206/* Allow binding to any address for transparent proxying */ 207/* Allow setting TOS (type of service) */ 208/* Allow setting promiscuous mode */ 209/* Allow clearing driver statistics */ 210/* Allow multicasting */ 211/* Allow read/write of device-specific registers */ 212/* Allow activation of ATM control sockets */ 213 214#define CAP_NET_ADMIN 12 215 216/* Allow use of RAW sockets */ 217/* Allow use of PACKET sockets */ 218 219#define CAP_NET_RAW 13 220 221/* Allow locking of shared memory segments */ 222/* Allow mlock and mlockall (which doesn't really have anything to do 223 with IPC) */ 224 225#define CAP_IPC_LOCK 14 226 227/* Override IPC ownership checks */ 228 229#define CAP_IPC_OWNER 15 230 231/* Insert and remove kernel modules - modify kernel without limit */ 232#define CAP_SYS_MODULE 16 233 234/* Allow ioperm/iopl access */ 235/* Allow sending USB messages to any device via /proc/bus/usb */ 236 237#define CAP_SYS_RAWIO 17 238 239/* Allow use of chroot() */ 240 241#define CAP_SYS_CHROOT 18 242 243/* Allow ptrace() of any process */ 244 245#define CAP_SYS_PTRACE 19 246 247/* Allow configuration of process accounting */ 248 249#define CAP_SYS_PACCT 20 250 251/* Allow configuration of the secure attention key */ 252/* Allow administration of the random device */ 253/* Allow examination and configuration of disk quotas */ 254/* Allow configuring the kernel's syslog (printk behaviour) */ 255/* Allow setting the domainname */ 256/* Allow setting the hostname */ 257/* Allow calling bdflush() */ 258/* Allow mount() and umount(), setting up new smb connection */ 259/* Allow some autofs root ioctls */ 260/* Allow nfsservctl */ 261/* Allow VM86_REQUEST_IRQ */ 262/* Allow to read/write pci config on alpha */ 263/* Allow irix_prctl on mips (setstacksize) */ 264/* Allow flushing all cache on m68k (sys_cacheflush) */ 265/* Allow removing semaphores */ 266/* Used instead of CAP_CHOWN to "chown" IPC message queues, semaphores 267 and shared memory */ 268/* Allow locking/unlocking of shared memory segment */ 269/* Allow turning swap on/off */ 270/* Allow forged pids on socket credentials passing */ 271/* Allow setting readahead and flushing buffers on block devices */ 272/* Allow setting geometry in floppy driver */ 273/* Allow turning DMA on/off in xd driver */ 274/* Allow administration of md devices (mostly the above, but some 275 extra ioctls) */ 276/* Allow tuning the ide driver */ 277/* Allow access to the nvram device */ 278/* Allow administration of apm_bios, serial and bttv (TV) device */ 279/* Allow manufacturer commands in isdn CAPI support driver */ 280/* Allow reading non-standardized portions of pci configuration space */ 281/* Allow DDI debug ioctl on sbpcd driver */ 282/* Allow setting up serial ports */ 283/* Allow sending raw qic-117 commands */ 284/* Allow enabling/disabling tagged queuing on SCSI controllers and sending 285 arbitrary SCSI commands */ 286/* Allow setting encryption key on loopback filesystem */ 287/* Allow setting zone reclaim policy */ 288 289#define CAP_SYS_ADMIN 21 290 291/* Allow use of reboot() */ 292 293#define CAP_SYS_BOOT 22 294 295/* Allow raising priority and setting priority on other (different 296 UID) processes */ 297/* Allow use of FIFO and round-robin (realtime) scheduling on own 298 processes and setting the scheduling algorithm used by another 299 process. */ 300/* Allow setting cpu affinity on other processes */ 301 302#define CAP_SYS_NICE 23 303 304/* Override resource limits. Set resource limits. */ 305/* Override quota limits. */ 306/* Override reserved space on ext2 filesystem */ 307/* Modify data journaling mode on ext3 filesystem (uses journaling 308 resources) */ 309/* NOTE: ext2 honors fsuid when checking for resource overrides, so 310 you can override using fsuid too */ 311/* Override size restrictions on IPC message queues */ 312/* Allow more than 64hz interrupts from the real-time clock */ 313/* Override max number of consoles on console allocation */ 314/* Override max number of keymaps */ 315 316#define CAP_SYS_RESOURCE 24 317 318/* Allow manipulation of system clock */ 319/* Allow irix_stime on mips */ 320/* Allow setting the real-time clock */ 321 322#define CAP_SYS_TIME 25 323 324/* Allow configuration of tty devices */ 325/* Allow vhangup() of tty */ 326 327#define CAP_SYS_TTY_CONFIG 26 328 329/* Allow the privileged aspects of mknod() */ 330 331#define CAP_MKNOD 27 332 333/* Allow taking of leases on files */ 334 335#define CAP_LEASE 28 336 337#define CAP_AUDIT_WRITE 29 338 339#define CAP_AUDIT_CONTROL 30 340 341#define CAP_SETFCAP 31 342 343/* Override MAC access. 344 The base kernel enforces no MAC policy. 345 An LSM may enforce a MAC policy, and if it does and it chooses 346 to implement capability based overrides of that policy, this is 347 the capability it should use to do so. */ 348 349#define CAP_MAC_OVERRIDE 32 350 351/* Allow MAC configuration or state changes. 352 The base kernel requires no MAC configuration. 353 An LSM may enforce a MAC policy, and if it does and it chooses 354 to implement capability based checks on modifications to that 355 policy or the data required to maintain it, this is the 356 capability it should use to do so. */ 357 358#define CAP_MAC_ADMIN 33 359 360#define CAP_LAST_CAP CAP_MAC_ADMIN 361 362#define cap_valid(x) ((x) >= 0 && (x) <= CAP_LAST_CAP) 363 364/* 365 * Bit location of each capability (used by user-space library and kernel) 366 */ 367 368#define CAP_TO_INDEX(x) ((x) >> 5) /* 1 << 5 == bits in __u32 */ 369#define CAP_TO_MASK(x) (1 << ((x) & 31)) /* mask for indexed __u32 */ 370 371#ifdef __KERNEL__ 372 373/* 374 * Internal kernel functions only 375 */ 376 377#define CAP_FOR_EACH_U32(__capi) \ 378 for (__capi = 0; __capi < _KERNEL_CAPABILITY_U32S; ++__capi) 379 380/* 381 * CAP_FS_MASK and CAP_NFSD_MASKS: 382 * 383 * The fs mask is all the privileges that fsuid==0 historically meant. 384 * At one time in the past, that included CAP_MKNOD and CAP_LINUX_IMMUTABLE. 385 * 386 * It has never meant setting security.* and trusted.* xattrs. 387 * 388 * We could also define fsmask as follows: 389 * 1. CAP_FS_MASK is the privilege to bypass all fs-related DAC permissions 390 * 2. The security.* and trusted.* xattrs are fs-related MAC permissions 391 */ 392 393# define CAP_FS_MASK_B0 (CAP_TO_MASK(CAP_CHOWN) \ 394 | CAP_TO_MASK(CAP_MKNOD) \ 395 | CAP_TO_MASK(CAP_DAC_OVERRIDE) \ 396 | CAP_TO_MASK(CAP_DAC_READ_SEARCH) \ 397 | CAP_TO_MASK(CAP_FOWNER) \ 398 | CAP_TO_MASK(CAP_FSETID)) 399 400# define CAP_FS_MASK_B1 (CAP_TO_MASK(CAP_MAC_OVERRIDE)) 401 402#if _KERNEL_CAPABILITY_U32S != 2 403# error Fix up hand-coded capability macro initializers 404#else /* HAND-CODED capability initializers */ 405 406# define CAP_EMPTY_SET ((kernel_cap_t){{ 0, 0 }}) 407# define CAP_FULL_SET ((kernel_cap_t){{ ~0, ~0 }}) 408# define CAP_INIT_EFF_SET ((kernel_cap_t){{ ~CAP_TO_MASK(CAP_SETPCAP), ~0 }}) 409# define CAP_FS_SET ((kernel_cap_t){{ CAP_FS_MASK_B0 \ 410 | CAP_TO_MASK(CAP_LINUX_IMMUTABLE), \ 411 CAP_FS_MASK_B1 } }) 412# define CAP_NFSD_SET ((kernel_cap_t){{ CAP_FS_MASK_B0 \ 413 | CAP_TO_MASK(CAP_SYS_RESOURCE), \ 414 CAP_FS_MASK_B1 } }) 415 416#endif /* _KERNEL_CAPABILITY_U32S != 2 */ 417 418#define CAP_INIT_INH_SET CAP_EMPTY_SET 419 420# define cap_clear(c) do { (c) = __cap_empty_set; } while (0) 421# define cap_set_full(c) do { (c) = __cap_full_set; } while (0) 422# define cap_set_init_eff(c) do { (c) = __cap_init_eff_set; } while (0) 423 424#define cap_raise(c, flag) ((c).cap[CAP_TO_INDEX(flag)] |= CAP_TO_MASK(flag)) 425#define cap_lower(c, flag) ((c).cap[CAP_TO_INDEX(flag)] &= ~CAP_TO_MASK(flag)) 426#define cap_raised(c, flag) ((c).cap[CAP_TO_INDEX(flag)] & CAP_TO_MASK(flag)) 427 428#define CAP_BOP_ALL(c, a, b, OP) \ 429do { \ 430 unsigned __capi; \ 431 CAP_FOR_EACH_U32(__capi) { \ 432 c.cap[__capi] = a.cap[__capi] OP b.cap[__capi]; \ 433 } \ 434} while (0) 435 436#define CAP_UOP_ALL(c, a, OP) \ 437do { \ 438 unsigned __capi; \ 439 CAP_FOR_EACH_U32(__capi) { \ 440 c.cap[__capi] = OP a.cap[__capi]; \ 441 } \ 442} while (0) 443 444static inline kernel_cap_t cap_combine(const kernel_cap_t a, 445 const kernel_cap_t b) 446{ 447 kernel_cap_t dest; 448 CAP_BOP_ALL(dest, a, b, |); 449 return dest; 450} 451 452static inline kernel_cap_t cap_intersect(const kernel_cap_t a, 453 const kernel_cap_t b) 454{ 455 kernel_cap_t dest; 456 CAP_BOP_ALL(dest, a, b, &); 457 return dest; 458} 459 460static inline kernel_cap_t cap_drop(const kernel_cap_t a, 461 const kernel_cap_t drop) 462{ 463 kernel_cap_t dest; 464 CAP_BOP_ALL(dest, a, drop, &~); 465 return dest; 466} 467 468static inline kernel_cap_t cap_invert(const kernel_cap_t c) 469{ 470 kernel_cap_t dest; 471 CAP_UOP_ALL(dest, c, ~); 472 return dest; 473} 474 475static inline int cap_isclear(const kernel_cap_t a) 476{ 477 unsigned __capi; 478 CAP_FOR_EACH_U32(__capi) { 479 if (a.cap[__capi] != 0) 480 return 0; 481 } 482 return 1; 483} 484 485/* 486 * Check if "a" is a subset of "set". 487 * return 1 if ALL of the capabilities in "a" are also in "set" 488 * cap_issubset(0101, 1111) will return 1 489 * return 0 if ANY of the capabilities in "a" are not in "set" 490 * cap_issubset(1111, 0101) will return 0 491 */ 492static inline int cap_issubset(const kernel_cap_t a, const kernel_cap_t set) 493{ 494 kernel_cap_t dest; 495 dest = cap_drop(a, set); 496 return cap_isclear(dest); 497} 498 499/* Used to decide between falling back on the old suser() or fsuser(). */ 500 501static inline int cap_is_fs_cap(int cap) 502{ 503 const kernel_cap_t __cap_fs_set = CAP_FS_SET; 504 return !!(CAP_TO_MASK(cap) & __cap_fs_set.cap[CAP_TO_INDEX(cap)]); 505} 506 507static inline kernel_cap_t cap_drop_fs_set(const kernel_cap_t a) 508{ 509 const kernel_cap_t __cap_fs_set = CAP_FS_SET; 510 return cap_drop(a, __cap_fs_set); 511} 512 513static inline kernel_cap_t cap_raise_fs_set(const kernel_cap_t a, 514 const kernel_cap_t permitted) 515{ 516 const kernel_cap_t __cap_fs_set = CAP_FS_SET; 517 return cap_combine(a, 518 cap_intersect(permitted, __cap_fs_set)); 519} 520 521static inline kernel_cap_t cap_drop_nfsd_set(const kernel_cap_t a) 522{ 523 const kernel_cap_t __cap_fs_set = CAP_NFSD_SET; 524 return cap_drop(a, __cap_fs_set); 525} 526 527static inline kernel_cap_t cap_raise_nfsd_set(const kernel_cap_t a, 528 const kernel_cap_t permitted) 529{ 530 const kernel_cap_t __cap_nfsd_set = CAP_NFSD_SET; 531 return cap_combine(a, 532 cap_intersect(permitted, __cap_nfsd_set)); 533} 534 535extern const kernel_cap_t __cap_empty_set; 536extern const kernel_cap_t __cap_full_set; 537extern const kernel_cap_t __cap_init_eff_set; 538 539/** 540 * has_capability - Determine if a task has a superior capability available 541 * @t: The task in question 542 * @cap: The capability to be tested for 543 * 544 * Return true if the specified task has the given superior capability 545 * currently in effect, false if not. 546 * 547 * Note that this does not set PF_SUPERPRIV on the task. 548 */ 549#define has_capability(t, cap) (security_real_capable((t), (cap)) == 0) 550 551/** 552 * has_capability_noaudit - Determine if a task has a superior capability available (unaudited) 553 * @t: The task in question 554 * @cap: The capability to be tested for 555 * 556 * Return true if the specified task has the given superior capability 557 * currently in effect, false if not, but don't write an audit message for the 558 * check. 559 * 560 * Note that this does not set PF_SUPERPRIV on the task. 561 */ 562#define has_capability_noaudit(t, cap) \ 563 (security_real_capable_noaudit((t), (cap)) == 0) 564 565extern int capable(int cap); 566 567/* audit system wants to get cap info from files as well */ 568struct dentry; 569extern int get_vfs_caps_from_disk(const struct dentry *dentry, struct cpu_vfs_cap_data *cpu_caps); 570 571#endif /* __KERNEL__ */ 572 573#endif /* !_LINUX_CAPABILITY_H */ 574