1 /*- 2 * Copyright (c) 2008-2010, 2015 Robert N. M. Watson 3 * Copyright (c) 2012 FreeBSD Foundation 4 * All rights reserved. 5 * 6 * This software was developed at the University of Cambridge Computer 7 * Laboratory with support from a grant from Google, Inc. 8 * 9 * Portions of this software were developed by Pawel Jakub Dawidek under 10 * sponsorship from the FreeBSD Foundation. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31 * SUCH DAMAGE. 32 * 33 * $FreeBSD$ 34 */ 35 36 /* 37 * Definitions for FreeBSD capabilities facility. 38 */ 39 #ifndef _SYS_CAPSICUM_H_ 40 #define _SYS_CAPSICUM_H_ 41 42 #include <sys/cdefs.h> 43 #include <sys/param.h> 44 45 #include <sys/caprights.h> 46 #include <sys/file.h> 47 #include <sys/fcntl.h> 48 49 #ifndef _KERNEL 50 #include <stdbool.h> 51 #endif 52 53 #define CAPRIGHT(idx, bit) ((1ULL << (57 + (idx))) | (bit)) 54 55 /* 56 * Possible rights on capabilities. 57 * 58 * Notes: 59 * Some system calls don't require a capability in order to perform an 60 * operation on an fd. These include: close, dup, dup2. 61 * 62 * sendfile is authorized using CAP_READ on the file and CAP_WRITE on the 63 * socket. 64 * 65 * mmap() and aio*() system calls will need special attention as they may 66 * involve reads or writes depending a great deal on context. 67 */ 68 69 /* INDEX 0 */ 70 71 /* 72 * General file I/O. 73 */ 74 /* Allows for openat(O_RDONLY), read(2), readv(2). */ 75 #define CAP_READ CAPRIGHT(0, 0x0000000000000001ULL) 76 /* Allows for openat(O_WRONLY | O_APPEND), write(2), writev(2). */ 77 #define CAP_WRITE CAPRIGHT(0, 0x0000000000000002ULL) 78 /* Allows for lseek(fd, 0, SEEK_CUR). */ 79 #define CAP_SEEK_TELL CAPRIGHT(0, 0x0000000000000004ULL) 80 /* Allows for lseek(2). */ 81 #define CAP_SEEK (CAP_SEEK_TELL | 0x0000000000000008ULL) 82 /* Allows for aio_read(2), pread(2), preadv(2). */ 83 #define CAP_PREAD (CAP_SEEK | CAP_READ) 84 /* 85 * Allows for aio_write(2), openat(O_WRONLY) (without O_APPEND), pwrite(2), 86 * pwritev(2). 87 */ 88 #define CAP_PWRITE (CAP_SEEK | CAP_WRITE) 89 /* Allows for mmap(PROT_NONE). */ 90 #define CAP_MMAP CAPRIGHT(0, 0x0000000000000010ULL) 91 /* Allows for mmap(PROT_READ). */ 92 #define CAP_MMAP_R (CAP_MMAP | CAP_SEEK | CAP_READ) 93 /* Allows for mmap(PROT_WRITE). */ 94 #define CAP_MMAP_W (CAP_MMAP | CAP_SEEK | CAP_WRITE) 95 /* Allows for mmap(PROT_EXEC). */ 96 #define CAP_MMAP_X (CAP_MMAP | CAP_SEEK | 0x0000000000000020ULL) 97 /* Allows for mmap(PROT_READ | PROT_WRITE). */ 98 #define CAP_MMAP_RW (CAP_MMAP_R | CAP_MMAP_W) 99 /* Allows for mmap(PROT_READ | PROT_EXEC). */ 100 #define CAP_MMAP_RX (CAP_MMAP_R | CAP_MMAP_X) 101 /* Allows for mmap(PROT_WRITE | PROT_EXEC). */ 102 #define CAP_MMAP_WX (CAP_MMAP_W | CAP_MMAP_X) 103 /* Allows for mmap(PROT_READ | PROT_WRITE | PROT_EXEC). */ 104 #define CAP_MMAP_RWX (CAP_MMAP_R | CAP_MMAP_W | CAP_MMAP_X) 105 /* Allows for openat(O_CREAT). */ 106 #define CAP_CREATE CAPRIGHT(0, 0x0000000000000040ULL) 107 /* Allows for openat(O_EXEC) and fexecve(2) in turn. */ 108 #define CAP_FEXECVE CAPRIGHT(0, 0x0000000000000080ULL) 109 /* Allows for openat(O_SYNC), openat(O_FSYNC), fsync(2), aio_fsync(2). */ 110 #define CAP_FSYNC CAPRIGHT(0, 0x0000000000000100ULL) 111 /* Allows for openat(O_TRUNC), ftruncate(2). */ 112 #define CAP_FTRUNCATE CAPRIGHT(0, 0x0000000000000200ULL) 113 114 /* Lookups - used to constrain *at() calls. */ 115 #define CAP_LOOKUP CAPRIGHT(0, 0x0000000000000400ULL) 116 117 /* VFS methods. */ 118 /* Allows for fchdir(2). */ 119 #define CAP_FCHDIR CAPRIGHT(0, 0x0000000000000800ULL) 120 /* Allows for fchflags(2). */ 121 #define CAP_FCHFLAGS CAPRIGHT(0, 0x0000000000001000ULL) 122 /* Allows for fchflags(2) and chflagsat(2). */ 123 #define CAP_CHFLAGSAT (CAP_FCHFLAGS | CAP_LOOKUP) 124 /* Allows for fchmod(2). */ 125 #define CAP_FCHMOD CAPRIGHT(0, 0x0000000000002000ULL) 126 /* Allows for fchmod(2) and fchmodat(2). */ 127 #define CAP_FCHMODAT (CAP_FCHMOD | CAP_LOOKUP) 128 /* Allows for fchown(2). */ 129 #define CAP_FCHOWN CAPRIGHT(0, 0x0000000000004000ULL) 130 /* Allows for fchown(2) and fchownat(2). */ 131 #define CAP_FCHOWNAT (CAP_FCHOWN | CAP_LOOKUP) 132 /* Allows for fcntl(2). */ 133 #define CAP_FCNTL CAPRIGHT(0, 0x0000000000008000ULL) 134 /* 135 * Allows for flock(2), openat(O_SHLOCK), openat(O_EXLOCK), 136 * fcntl(F_SETLK_REMOTE), fcntl(F_SETLKW), fcntl(F_SETLK), fcntl(F_GETLK). 137 */ 138 #define CAP_FLOCK CAPRIGHT(0, 0x0000000000010000ULL) 139 /* Allows for fpathconf(2). */ 140 #define CAP_FPATHCONF CAPRIGHT(0, 0x0000000000020000ULL) 141 /* Allows for UFS background-fsck operations. */ 142 #define CAP_FSCK CAPRIGHT(0, 0x0000000000040000ULL) 143 /* Allows for fstat(2). */ 144 #define CAP_FSTAT CAPRIGHT(0, 0x0000000000080000ULL) 145 /* Allows for fstat(2), fstatat(2) and faccessat(2). */ 146 #define CAP_FSTATAT (CAP_FSTAT | CAP_LOOKUP) 147 /* Allows for fstatfs(2). */ 148 #define CAP_FSTATFS CAPRIGHT(0, 0x0000000000100000ULL) 149 /* Allows for futimens(2) and futimes(2). */ 150 #define CAP_FUTIMES CAPRIGHT(0, 0x0000000000200000ULL) 151 /* Allows for futimens(2), futimes(2), futimesat(2) and utimensat(2). */ 152 #define CAP_FUTIMESAT (CAP_FUTIMES | CAP_LOOKUP) 153 /* Allows for linkat(2) (target directory descriptor). */ 154 #define CAP_LINKAT_TARGET (CAP_LOOKUP | 0x0000000000400000ULL) 155 /* Allows for mkdirat(2). */ 156 #define CAP_MKDIRAT (CAP_LOOKUP | 0x0000000000800000ULL) 157 /* Allows for mkfifoat(2). */ 158 #define CAP_MKFIFOAT (CAP_LOOKUP | 0x0000000001000000ULL) 159 /* Allows for mknodat(2). */ 160 #define CAP_MKNODAT (CAP_LOOKUP | 0x0000000002000000ULL) 161 /* Allows for renameat(2) (source directory descriptor). */ 162 #define CAP_RENAMEAT_SOURCE (CAP_LOOKUP | 0x0000000004000000ULL) 163 /* Allows for symlinkat(2). */ 164 #define CAP_SYMLINKAT (CAP_LOOKUP | 0x0000000008000000ULL) 165 /* 166 * Allows for unlinkat(2) and renameat(2) if destination object exists and 167 * will be removed. 168 */ 169 #define CAP_UNLINKAT (CAP_LOOKUP | 0x0000000010000000ULL) 170 171 /* Socket operations. */ 172 /* Allows for accept(2) and accept4(2). */ 173 #define CAP_ACCEPT CAPRIGHT(0, 0x0000000020000000ULL) 174 /* Allows for bind(2). */ 175 #define CAP_BIND CAPRIGHT(0, 0x0000000040000000ULL) 176 /* Allows for connect(2). */ 177 #define CAP_CONNECT CAPRIGHT(0, 0x0000000080000000ULL) 178 /* Allows for getpeername(2). */ 179 #define CAP_GETPEERNAME CAPRIGHT(0, 0x0000000100000000ULL) 180 /* Allows for getsockname(2). */ 181 #define CAP_GETSOCKNAME CAPRIGHT(0, 0x0000000200000000ULL) 182 /* Allows for getsockopt(2). */ 183 #define CAP_GETSOCKOPT CAPRIGHT(0, 0x0000000400000000ULL) 184 /* Allows for listen(2). */ 185 #define CAP_LISTEN CAPRIGHT(0, 0x0000000800000000ULL) 186 /* Allows for sctp_peeloff(2). */ 187 #define CAP_PEELOFF CAPRIGHT(0, 0x0000001000000000ULL) 188 #define CAP_RECV CAP_READ 189 #define CAP_SEND CAP_WRITE 190 /* Allows for setsockopt(2). */ 191 #define CAP_SETSOCKOPT CAPRIGHT(0, 0x0000002000000000ULL) 192 /* Allows for shutdown(2). */ 193 #define CAP_SHUTDOWN CAPRIGHT(0, 0x0000004000000000ULL) 194 195 /* Allows for bindat(2) on a directory descriptor. */ 196 #define CAP_BINDAT (CAP_LOOKUP | 0x0000008000000000ULL) 197 /* Allows for connectat(2) on a directory descriptor. */ 198 #define CAP_CONNECTAT (CAP_LOOKUP | 0x0000010000000000ULL) 199 200 /* Allows for linkat(2) (source directory descriptor). */ 201 #define CAP_LINKAT_SOURCE (CAP_LOOKUP | 0x0000020000000000ULL) 202 /* Allows for renameat(2) (target directory descriptor). */ 203 #define CAP_RENAMEAT_TARGET (CAP_LOOKUP | 0x0000040000000000ULL) 204 205 #define CAP_SOCK_CLIENT \ 206 (CAP_CONNECT | CAP_GETPEERNAME | CAP_GETSOCKNAME | CAP_GETSOCKOPT | \ 207 CAP_PEELOFF | CAP_RECV | CAP_SEND | CAP_SETSOCKOPT | CAP_SHUTDOWN) 208 #define CAP_SOCK_SERVER \ 209 (CAP_ACCEPT | CAP_BIND | CAP_GETPEERNAME | CAP_GETSOCKNAME | \ 210 CAP_GETSOCKOPT | CAP_LISTEN | CAP_PEELOFF | CAP_RECV | CAP_SEND | \ 211 CAP_SETSOCKOPT | CAP_SHUTDOWN) 212 213 /* All used bits for index 0. */ 214 #define CAP_ALL0 CAPRIGHT(0, 0x000007FFFFFFFFFFULL) 215 216 /* Available bits for index 0. */ 217 #define CAP_UNUSED0_44 CAPRIGHT(0, 0x0000080000000000ULL) 218 /* ... */ 219 #define CAP_UNUSED0_57 CAPRIGHT(0, 0x0100000000000000ULL) 220 221 /* INDEX 1 */ 222 223 /* Mandatory Access Control. */ 224 /* Allows for mac_get_fd(3). */ 225 #define CAP_MAC_GET CAPRIGHT(1, 0x0000000000000001ULL) 226 /* Allows for mac_set_fd(3). */ 227 #define CAP_MAC_SET CAPRIGHT(1, 0x0000000000000002ULL) 228 229 /* Methods on semaphores. */ 230 #define CAP_SEM_GETVALUE CAPRIGHT(1, 0x0000000000000004ULL) 231 #define CAP_SEM_POST CAPRIGHT(1, 0x0000000000000008ULL) 232 #define CAP_SEM_WAIT CAPRIGHT(1, 0x0000000000000010ULL) 233 234 /* Allows select(2) and poll(2) on descriptor. */ 235 #define CAP_EVENT CAPRIGHT(1, 0x0000000000000020ULL) 236 /* Allows for kevent(2) on kqueue descriptor with eventlist != NULL. */ 237 #define CAP_KQUEUE_EVENT CAPRIGHT(1, 0x0000000000000040ULL) 238 239 /* Strange and powerful rights that should not be given lightly. */ 240 /* Allows for ioctl(2). */ 241 #define CAP_IOCTL CAPRIGHT(1, 0x0000000000000080ULL) 242 #define CAP_TTYHOOK CAPRIGHT(1, 0x0000000000000100ULL) 243 244 /* Process management via process descriptors. */ 245 /* Allows for pdgetpid(2). */ 246 #define CAP_PDGETPID CAPRIGHT(1, 0x0000000000000200ULL) 247 /* Allows for pdwait4(2). */ 248 #define CAP_PDWAIT CAPRIGHT(1, 0x0000000000000400ULL) 249 /* Allows for pdkill(2). */ 250 #define CAP_PDKILL CAPRIGHT(1, 0x0000000000000800ULL) 251 252 /* Extended attributes. */ 253 /* Allows for extattr_delete_fd(2). */ 254 #define CAP_EXTATTR_DELETE CAPRIGHT(1, 0x0000000000001000ULL) 255 /* Allows for extattr_get_fd(2). */ 256 #define CAP_EXTATTR_GET CAPRIGHT(1, 0x0000000000002000ULL) 257 /* Allows for extattr_list_fd(2). */ 258 #define CAP_EXTATTR_LIST CAPRIGHT(1, 0x0000000000004000ULL) 259 /* Allows for extattr_set_fd(2). */ 260 #define CAP_EXTATTR_SET CAPRIGHT(1, 0x0000000000008000ULL) 261 262 /* Access Control Lists. */ 263 /* Allows for acl_valid_fd_np(3). */ 264 #define CAP_ACL_CHECK CAPRIGHT(1, 0x0000000000010000ULL) 265 /* Allows for acl_delete_fd_np(3). */ 266 #define CAP_ACL_DELETE CAPRIGHT(1, 0x0000000000020000ULL) 267 /* Allows for acl_get_fd(3) and acl_get_fd_np(3). */ 268 #define CAP_ACL_GET CAPRIGHT(1, 0x0000000000040000ULL) 269 /* Allows for acl_set_fd(3) and acl_set_fd_np(3). */ 270 #define CAP_ACL_SET CAPRIGHT(1, 0x0000000000080000ULL) 271 272 /* Allows for kevent(2) on kqueue descriptor with changelist != NULL. */ 273 #define CAP_KQUEUE_CHANGE CAPRIGHT(1, 0x0000000000100000ULL) 274 275 #define CAP_KQUEUE (CAP_KQUEUE_EVENT | CAP_KQUEUE_CHANGE) 276 277 /* All used bits for index 1. */ 278 #define CAP_ALL1 CAPRIGHT(1, 0x00000000001FFFFFULL) 279 280 /* Available bits for index 1. */ 281 #define CAP_UNUSED1_22 CAPRIGHT(1, 0x0000000000200000ULL) 282 /* ... */ 283 #define CAP_UNUSED1_57 CAPRIGHT(1, 0x0100000000000000ULL) 284 285 /* Backward compatibility. */ 286 #define CAP_POLL_EVENT CAP_EVENT 287 288 #define CAP_ALL(rights) do { \ 289 (rights)->cr_rights[0] = \ 290 ((uint64_t)CAP_RIGHTS_VERSION << 62) | CAP_ALL0; \ 291 (rights)->cr_rights[1] = CAP_ALL1; \ 292 } while (0) 293 294 #define CAP_NONE(rights) do { \ 295 (rights)->cr_rights[0] = \ 296 ((uint64_t)CAP_RIGHTS_VERSION << 62) | CAPRIGHT(0, 0ULL); \ 297 (rights)->cr_rights[1] = CAPRIGHT(1, 0ULL); \ 298 } while (0) 299 300 #define CAPRVER(right) ((int)((right) >> 62)) 301 #define CAPVER(rights) CAPRVER((rights)->cr_rights[0]) 302 #define CAPARSIZE(rights) (CAPVER(rights) + 2) 303 #define CAPIDXBIT(right) ((int)(((right) >> 57) & 0x1F)) 304 305 /* 306 * Allowed fcntl(2) commands. 307 */ 308 #define CAP_FCNTL_GETFL (1 << F_GETFL) 309 #define CAP_FCNTL_SETFL (1 << F_SETFL) 310 #define CAP_FCNTL_GETOWN (1 << F_GETOWN) 311 #define CAP_FCNTL_SETOWN (1 << F_SETOWN) 312 #define CAP_FCNTL_ALL (CAP_FCNTL_GETFL | CAP_FCNTL_SETFL | \ 313 CAP_FCNTL_GETOWN | CAP_FCNTL_SETOWN) 314 315 #define CAP_IOCTLS_ALL SSIZE_MAX 316 317 __BEGIN_DECLS 318 319 #define cap_rights_init(...) \ 320 __cap_rights_init(CAP_RIGHTS_VERSION, __VA_ARGS__, 0ULL) 321 cap_rights_t *__cap_rights_init(int version, cap_rights_t *rights, ...); 322 323 #define cap_rights_set(...) \ 324 __cap_rights_set(__VA_ARGS__, 0ULL) 325 cap_rights_t *__cap_rights_set(cap_rights_t *rights, ...); 326 327 #define cap_rights_clear(...) \ 328 __cap_rights_clear(__VA_ARGS__, 0ULL) 329 cap_rights_t *__cap_rights_clear(cap_rights_t *rights, ...); 330 331 #define cap_rights_is_set(...) \ 332 __cap_rights_is_set(__VA_ARGS__, 0ULL) 333 bool __cap_rights_is_set(const cap_rights_t *rights, ...); 334 335 bool cap_rights_is_valid(const cap_rights_t *rights); 336 cap_rights_t *cap_rights_merge(cap_rights_t *dst, const cap_rights_t *src); 337 cap_rights_t *cap_rights_remove(cap_rights_t *dst, const cap_rights_t *src); 338 bool cap_rights_contains(const cap_rights_t *big, const cap_rights_t *little); 339 340 __END_DECLS 341 342 #ifdef _KERNEL 343 344 #include <sys/systm.h> 345 346 #define IN_CAPABILITY_MODE(td) (((td)->td_ucred->cr_flags & CRED_FLAG_CAPMODE) != 0) 347 348 struct filedesc; 349 struct filedescent; 350 351 /* 352 * Test whether a capability grants the requested rights. 353 */ 354 int cap_check(const cap_rights_t *havep, const cap_rights_t *needp); 355 /* 356 * Convert capability rights into VM access flags. 357 */ 358 u_char cap_rights_to_vmprot(cap_rights_t *havep); 359 360 /* 361 * For the purposes of procstat(1) and similar tools, allow kern_descrip.c to 362 * extract the rights from a capability. 363 */ 364 cap_rights_t *cap_rights_fde(struct filedescent *fde); 365 cap_rights_t *cap_rights(struct filedesc *fdp, int fd); 366 367 int cap_ioctl_check(struct filedesc *fdp, int fd, u_long cmd); 368 int cap_fcntl_check_fde(struct filedescent *fde, int cmd); 369 int cap_fcntl_check(struct filedesc *fdp, int fd, int cmd); 370 371 #else /* !_KERNEL */ 372 373 __BEGIN_DECLS 374 /* 375 * cap_enter(): Cause the process to enter capability mode, which will 376 * prevent it from directly accessing global namespaces. System calls will 377 * be limited to process-local, process-inherited, or file descriptor 378 * operations. If already in capability mode, a no-op. 379 */ 380 int cap_enter(void); 381 382 /* 383 * Are we sandboxed (in capability mode)? 384 * This is a libc wrapper around the cap_getmode(2) system call. 385 */ 386 bool cap_sandboxed(void); 387 388 /* 389 * cap_getmode(): Are we in capability mode? 390 */ 391 int cap_getmode(u_int *modep); 392 393 /* 394 * Limits capability rights for the given descriptor (CAP_*). 395 */ 396 int cap_rights_limit(int fd, const cap_rights_t *rights); 397 /* 398 * Returns capability rights for the given descriptor. 399 */ 400 #define cap_rights_get(fd, rights) \ 401 __cap_rights_get(CAP_RIGHTS_VERSION, (fd), (rights)) 402 int __cap_rights_get(int version, int fd, cap_rights_t *rights); 403 /* 404 * Limits allowed ioctls for the given descriptor. 405 */ 406 int cap_ioctls_limit(int fd, const cap_ioctl_t *cmds, size_t ncmds); 407 /* 408 * Returns array of allowed ioctls for the given descriptor. 409 * If all ioctls are allowed, the cmds array is not populated and 410 * the function returns CAP_IOCTLS_ALL. 411 */ 412 ssize_t cap_ioctls_get(int fd, cap_ioctl_t *cmds, size_t maxcmds); 413 /* 414 * Limits allowed fcntls for the given descriptor (CAP_FCNTL_*). 415 */ 416 int cap_fcntls_limit(int fd, uint32_t fcntlrights); 417 /* 418 * Returns bitmask of allowed fcntls for the given descriptor. 419 */ 420 int cap_fcntls_get(int fd, uint32_t *fcntlrightsp); 421 422 __END_DECLS 423 424 #endif /* !_KERNEL */ 425 426 #endif /* !_SYS_CAPSICUM_H_ */ 427