1 /* $OpenBSD: kern_pledge.c,v 1.301 2022/12/23 05:35:08 deraadt Exp $ */ 2 3 /* 4 * Copyright (c) 2015 Nicholas Marriott <nicm@openbsd.org> 5 * Copyright (c) 2015 Theo de Raadt <deraadt@openbsd.org> 6 * 7 * Permission to use, copy, modify, and distribute this software for any 8 * purpose with or without fee is hereby granted, provided that the above 9 * copyright notice and this permission notice appear in all copies. 10 * 11 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 12 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 13 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 14 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 15 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 16 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 17 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 18 */ 19 20 #include <sys/param.h> 21 #include <sys/mount.h> 22 #include <sys/proc.h> 23 #include <sys/mutex.h> 24 #include <sys/fcntl.h> 25 #include <sys/file.h> 26 #include <sys/namei.h> 27 #include <sys/socketvar.h> 28 #include <sys/vnode.h> 29 #include <sys/mman.h> 30 #include <sys/sysctl.h> 31 #include <sys/syslog.h> 32 #include <sys/ktrace.h> 33 #include <sys/acct.h> 34 #include <sys/swap.h> 35 36 #include <sys/ioctl.h> 37 #include <sys/termios.h> 38 #include <sys/tty.h> 39 #include <sys/device.h> 40 #include <sys/disklabel.h> 41 #include <sys/dkio.h> 42 #include <sys/mtio.h> 43 #include <sys/audioio.h> 44 #include <sys/videoio.h> 45 #include <net/bpf.h> 46 #include <net/route.h> 47 #include <net/if.h> 48 #include <net/if_var.h> 49 #include <netinet/in.h> 50 #include <netinet6/in6_var.h> 51 #include <netinet6/nd6.h> 52 #include <netinet/tcp.h> 53 #include <net/pfvar.h> 54 55 #include <sys/conf.h> 56 #include <sys/specdev.h> 57 #include <sys/signal.h> 58 #include <sys/signalvar.h> 59 #include <sys/syscall.h> 60 #include <sys/syscallargs.h> 61 #include <sys/systm.h> 62 63 #include <dev/biovar.h> 64 65 #define PLEDGENAMES 66 #include <sys/pledge.h> 67 68 #include "audio.h" 69 #include "bpfilter.h" 70 #include "pf.h" 71 #include "video.h" 72 #include "pty.h" 73 74 #if defined(__amd64__) 75 #include "vmm.h" 76 #if NVMM > 0 77 #include <machine/conf.h> 78 #endif 79 #endif 80 81 #include "drm.h" 82 83 uint64_t pledgereq_flags(const char *req); 84 int parsepledges(struct proc *p, const char *kname, 85 const char *promises, u_int64_t *fp); 86 int canonpath(const char *input, char *buf, size_t bufsize); 87 void unveil_destroy(struct process *ps); 88 89 /* #define DEBUG_PLEDGE */ 90 #ifdef DEBUG_PLEDGE 91 int debug_pledge = 1; 92 #define DPRINTF(x...) do { if (debug_pledge) printf(x); } while (0) 93 #define DNPRINTF(n,x...) do { if (debug_pledge >= (n)) printf(x); } while (0) 94 #else 95 #define DPRINTF(x...) 96 #define DNPRINTF(n,x...) 97 #endif 98 99 /* 100 * Ordered in blocks starting with least risky and most required. 101 */ 102 const uint64_t pledge_syscalls[SYS_MAXSYSCALL] = { 103 /* 104 * Minimum required 105 */ 106 [SYS_exit] = PLEDGE_ALWAYS, 107 [SYS_kbind] = PLEDGE_ALWAYS, 108 [SYS_msyscall] = PLEDGE_ALWAYS, 109 [SYS___get_tcb] = PLEDGE_ALWAYS, 110 [SYS___set_tcb] = PLEDGE_ALWAYS, 111 [SYS_pledge] = PLEDGE_ALWAYS, 112 [SYS_sendsyslog] = PLEDGE_ALWAYS, /* stack protector reporting */ 113 [SYS_thrkill] = PLEDGE_ALWAYS, /* raise, abort, stack pro */ 114 [SYS_utrace] = PLEDGE_ALWAYS, /* ltrace(1) from ld.so */ 115 116 /* "getting" information about self is considered safe */ 117 [SYS_getuid] = PLEDGE_STDIO, 118 [SYS_geteuid] = PLEDGE_STDIO, 119 [SYS_getresuid] = PLEDGE_STDIO, 120 [SYS_getgid] = PLEDGE_STDIO, 121 [SYS_getegid] = PLEDGE_STDIO, 122 [SYS_getresgid] = PLEDGE_STDIO, 123 [SYS_getgroups] = PLEDGE_STDIO, 124 [SYS_getlogin_r] = PLEDGE_STDIO, 125 [SYS_getpgrp] = PLEDGE_STDIO, 126 [SYS_getpgid] = PLEDGE_STDIO, 127 [SYS_getppid] = PLEDGE_STDIO, 128 [SYS_getsid] = PLEDGE_STDIO, 129 [SYS_getthrid] = PLEDGE_STDIO, 130 [SYS_getrlimit] = PLEDGE_STDIO, 131 [SYS_getrtable] = PLEDGE_STDIO, 132 [SYS_gettimeofday] = PLEDGE_STDIO, 133 [SYS_getdtablecount] = PLEDGE_STDIO, 134 [SYS_getrusage] = PLEDGE_STDIO, 135 [SYS_issetugid] = PLEDGE_STDIO, 136 [SYS_clock_getres] = PLEDGE_STDIO, 137 [SYS_clock_gettime] = PLEDGE_STDIO, 138 [SYS_getpid] = PLEDGE_STDIO, 139 140 /* 141 * Almost exclusively read-only, Very narrow subset. 142 * Use of "route", "inet", "dns", "ps", or "vminfo" 143 * expands access. 144 */ 145 [SYS_sysctl] = PLEDGE_STDIO, 146 147 /* Support for malloc(3) family of operations */ 148 [SYS_getentropy] = PLEDGE_STDIO, 149 [SYS_madvise] = PLEDGE_STDIO, 150 [SYS_minherit] = PLEDGE_STDIO, 151 [SYS_mmap] = PLEDGE_STDIO, 152 [SYS_mprotect] = PLEDGE_STDIO, 153 [SYS_mimmutable] = PLEDGE_STDIO, 154 [SYS_mquery] = PLEDGE_STDIO, 155 [SYS_munmap] = PLEDGE_STDIO, 156 [SYS_msync] = PLEDGE_STDIO, 157 [SYS_break] = PLEDGE_STDIO, 158 159 [SYS_umask] = PLEDGE_STDIO, 160 161 /* read/write operations */ 162 [SYS_read] = PLEDGE_STDIO, 163 [SYS_readv] = PLEDGE_STDIO, 164 [SYS_pread] = PLEDGE_STDIO, 165 [SYS_preadv] = PLEDGE_STDIO, 166 [SYS_write] = PLEDGE_STDIO, 167 [SYS_writev] = PLEDGE_STDIO, 168 [SYS_pwrite] = PLEDGE_STDIO, 169 [SYS_pwritev] = PLEDGE_STDIO, 170 [SYS_recvmsg] = PLEDGE_STDIO, 171 [SYS_recvmmsg] = PLEDGE_STDIO, 172 [SYS_recvfrom] = PLEDGE_STDIO, 173 [SYS_ftruncate] = PLEDGE_STDIO, 174 [SYS_lseek] = PLEDGE_STDIO, 175 [SYS_fpathconf] = PLEDGE_STDIO, 176 177 #if 1 178 [SYS_pad_mquery] = PLEDGE_STDIO, 179 [SYS_pad_mmap] = PLEDGE_STDIO, 180 [SYS_pad_pread] = PLEDGE_STDIO, 181 [SYS_pad_preadv] = PLEDGE_STDIO, 182 [SYS_pad_pwrite] = PLEDGE_STDIO, 183 [SYS_pad_pwritev] = PLEDGE_STDIO, 184 [SYS_pad_ftruncate] = PLEDGE_STDIO, 185 [SYS_pad_lseek] = PLEDGE_STDIO, 186 [SYS_pad_truncate] = PLEDGE_WPATH, 187 #endif 188 189 /* 190 * Address selection required a network pledge ("inet", 191 * "unix", "dns". 192 */ 193 [SYS_sendto] = PLEDGE_STDIO, 194 195 /* 196 * Address specification required a network pledge ("inet", 197 * "unix", "dns". SCM_RIGHTS requires "sendfd" or "recvfd". 198 */ 199 [SYS_sendmsg] = PLEDGE_STDIO, 200 [SYS_sendmmsg] = PLEDGE_STDIO, 201 202 /* Common signal operations */ 203 [SYS_nanosleep] = PLEDGE_STDIO, 204 [SYS_sigaltstack] = PLEDGE_STDIO, 205 [SYS_sigprocmask] = PLEDGE_STDIO, 206 [SYS_sigsuspend] = PLEDGE_STDIO, 207 [SYS_sigaction] = PLEDGE_STDIO, 208 [SYS_sigreturn] = PLEDGE_STDIO, 209 [SYS_sigpending] = PLEDGE_STDIO, 210 [SYS_getitimer] = PLEDGE_STDIO, 211 [SYS_setitimer] = PLEDGE_STDIO, 212 213 /* 214 * To support event driven programming. 215 */ 216 [SYS_poll] = PLEDGE_STDIO, 217 [SYS_ppoll] = PLEDGE_STDIO, 218 [SYS_kevent] = PLEDGE_STDIO, 219 [SYS_kqueue] = PLEDGE_STDIO, 220 [SYS_select] = PLEDGE_STDIO, 221 [SYS_pselect] = PLEDGE_STDIO, 222 223 [SYS_fstat] = PLEDGE_STDIO, 224 [SYS_fsync] = PLEDGE_STDIO, 225 226 [SYS_setsockopt] = PLEDGE_STDIO, /* narrow whitelist */ 227 [SYS_getsockopt] = PLEDGE_STDIO, /* narrow whitelist */ 228 229 /* F_SETOWN requires PLEDGE_PROC */ 230 [SYS_fcntl] = PLEDGE_STDIO, 231 232 [SYS_close] = PLEDGE_STDIO, 233 [SYS_dup] = PLEDGE_STDIO, 234 [SYS_dup2] = PLEDGE_STDIO, 235 [SYS_dup3] = PLEDGE_STDIO, 236 [SYS_closefrom] = PLEDGE_STDIO, 237 [SYS_shutdown] = PLEDGE_STDIO, 238 [SYS_fchdir] = PLEDGE_STDIO, /* XXX consider tightening */ 239 240 [SYS_pipe] = PLEDGE_STDIO, 241 [SYS_pipe2] = PLEDGE_STDIO, 242 [SYS_socketpair] = PLEDGE_STDIO, 243 244 [SYS_wait4] = PLEDGE_STDIO, 245 246 /* 247 * Can kill self with "stdio". Killing another pid 248 * requires "proc" 249 */ 250 [SYS_kill] = PLEDGE_STDIO, 251 252 /* 253 * FIONREAD/FIONBIO for "stdio" 254 * Other ioctl are selectively allowed based upon other pledges. 255 */ 256 [SYS_ioctl] = PLEDGE_STDIO, 257 258 /* 259 * Path access/creation calls encounter many extensive 260 * checks done during pledge_namei() 261 */ 262 [SYS_open] = PLEDGE_STDIO, 263 [SYS_stat] = PLEDGE_STDIO, 264 [SYS_access] = PLEDGE_STDIO, 265 [SYS_readlink] = PLEDGE_STDIO, 266 [SYS___realpath] = PLEDGE_STDIO, 267 268 [SYS_adjtime] = PLEDGE_STDIO, /* setting requires "settime" */ 269 [SYS_adjfreq] = PLEDGE_SETTIME, 270 [SYS_settimeofday] = PLEDGE_SETTIME, 271 272 /* 273 * Needed by threaded programs 274 * XXX should we have a new "threads"? 275 */ 276 [SYS___tfork] = PLEDGE_STDIO, 277 [SYS_sched_yield] = PLEDGE_STDIO, 278 [SYS_futex] = PLEDGE_STDIO, 279 [SYS___thrsleep] = PLEDGE_STDIO, 280 [SYS___thrwakeup] = PLEDGE_STDIO, 281 [SYS___threxit] = PLEDGE_STDIO, 282 [SYS___thrsigdivert] = PLEDGE_STDIO, 283 284 [SYS_fork] = PLEDGE_PROC, 285 [SYS_vfork] = PLEDGE_PROC, 286 [SYS_setpgid] = PLEDGE_PROC, 287 [SYS_setsid] = PLEDGE_PROC, 288 289 [SYS_setrlimit] = PLEDGE_PROC | PLEDGE_ID, 290 [SYS_getpriority] = PLEDGE_PROC | PLEDGE_ID, 291 292 [SYS_setpriority] = PLEDGE_PROC | PLEDGE_ID, 293 294 [SYS_setuid] = PLEDGE_ID, 295 [SYS_seteuid] = PLEDGE_ID, 296 [SYS_setreuid] = PLEDGE_ID, 297 [SYS_setresuid] = PLEDGE_ID, 298 [SYS_setgid] = PLEDGE_ID, 299 [SYS_setegid] = PLEDGE_ID, 300 [SYS_setregid] = PLEDGE_ID, 301 [SYS_setresgid] = PLEDGE_ID, 302 [SYS_setgroups] = PLEDGE_ID, 303 [SYS_setlogin] = PLEDGE_ID, 304 [SYS_setrtable] = PLEDGE_ID, 305 306 [SYS_unveil] = PLEDGE_UNVEIL, 307 308 [SYS_execve] = PLEDGE_EXEC, 309 310 [SYS_chdir] = PLEDGE_RPATH, 311 [SYS_openat] = PLEDGE_RPATH | PLEDGE_WPATH, 312 [SYS_fstatat] = PLEDGE_RPATH | PLEDGE_WPATH, 313 [SYS_faccessat] = PLEDGE_RPATH | PLEDGE_WPATH, 314 [SYS_readlinkat] = PLEDGE_RPATH | PLEDGE_WPATH, 315 [SYS_lstat] = PLEDGE_RPATH | PLEDGE_WPATH | PLEDGE_TMPPATH, 316 [SYS_truncate] = PLEDGE_WPATH, 317 [SYS_rename] = PLEDGE_RPATH | PLEDGE_CPATH, 318 [SYS_rmdir] = PLEDGE_CPATH, 319 [SYS_renameat] = PLEDGE_CPATH, 320 [SYS_link] = PLEDGE_CPATH, 321 [SYS_linkat] = PLEDGE_CPATH, 322 [SYS_symlink] = PLEDGE_CPATH, 323 [SYS_symlinkat] = PLEDGE_CPATH, 324 [SYS_unlink] = PLEDGE_CPATH | PLEDGE_TMPPATH, 325 [SYS_unlinkat] = PLEDGE_CPATH, 326 [SYS_mkdir] = PLEDGE_CPATH, 327 [SYS_mkdirat] = PLEDGE_CPATH, 328 329 [SYS_mkfifo] = PLEDGE_DPATH, 330 [SYS_mkfifoat] = PLEDGE_DPATH, 331 [SYS_mknod] = PLEDGE_DPATH, 332 [SYS_mknodat] = PLEDGE_DPATH, 333 334 [SYS_revoke] = PLEDGE_TTY, /* also requires PLEDGE_RPATH */ 335 336 /* 337 * Classify as RPATH|WPATH, because of path information leakage. 338 * WPATH due to unknown use of mk*temp(3) on non-/tmp paths.. 339 */ 340 [SYS___getcwd] = PLEDGE_RPATH | PLEDGE_WPATH, 341 342 /* Classify as RPATH, because these leak path information */ 343 [SYS_getdents] = PLEDGE_RPATH, 344 [SYS_getfsstat] = PLEDGE_RPATH, 345 [SYS_statfs] = PLEDGE_RPATH, 346 [SYS_fstatfs] = PLEDGE_RPATH, 347 [SYS_pathconf] = PLEDGE_RPATH, 348 349 [SYS_utimes] = PLEDGE_FATTR, 350 [SYS_futimes] = PLEDGE_FATTR, 351 [SYS_utimensat] = PLEDGE_FATTR, 352 [SYS_futimens] = PLEDGE_FATTR, 353 [SYS_chmod] = PLEDGE_FATTR, 354 [SYS_fchmod] = PLEDGE_FATTR, 355 [SYS_fchmodat] = PLEDGE_FATTR, 356 [SYS_chflags] = PLEDGE_FATTR, 357 [SYS_chflagsat] = PLEDGE_FATTR, 358 [SYS_fchflags] = PLEDGE_FATTR, 359 360 [SYS_chown] = PLEDGE_CHOWN, 361 [SYS_fchownat] = PLEDGE_CHOWN, 362 [SYS_lchown] = PLEDGE_CHOWN, 363 [SYS_fchown] = PLEDGE_CHOWN, 364 365 [SYS_socket] = PLEDGE_INET | PLEDGE_UNIX | PLEDGE_DNS, 366 [SYS_connect] = PLEDGE_INET | PLEDGE_UNIX | PLEDGE_DNS, 367 [SYS_bind] = PLEDGE_INET | PLEDGE_UNIX | PLEDGE_DNS, 368 [SYS_getsockname] = PLEDGE_INET | PLEDGE_UNIX | PLEDGE_DNS, 369 370 [SYS_listen] = PLEDGE_INET | PLEDGE_UNIX, 371 [SYS_accept4] = PLEDGE_INET | PLEDGE_UNIX, 372 [SYS_accept] = PLEDGE_INET | PLEDGE_UNIX, 373 [SYS_getpeername] = PLEDGE_INET | PLEDGE_UNIX, 374 375 [SYS_flock] = PLEDGE_FLOCK, 376 377 [SYS_ypconnect] = PLEDGE_GETPW, 378 379 [SYS_swapctl] = PLEDGE_VMINFO, 380 }; 381 382 static const struct { 383 char *name; 384 uint64_t flags; 385 } pledgereq[] = { 386 { "audio", PLEDGE_AUDIO }, 387 { "bpf", PLEDGE_BPF }, 388 { "chown", PLEDGE_CHOWN | PLEDGE_CHOWNUID }, 389 { "cpath", PLEDGE_CPATH }, 390 { "disklabel", PLEDGE_DISKLABEL }, 391 { "dns", PLEDGE_DNS }, 392 { "dpath", PLEDGE_DPATH }, 393 { "drm", PLEDGE_DRM }, 394 { "error", PLEDGE_ERROR }, 395 { "exec", PLEDGE_EXEC }, 396 { "fattr", PLEDGE_FATTR | PLEDGE_CHOWN }, 397 { "flock", PLEDGE_FLOCK }, 398 { "getpw", PLEDGE_GETPW }, 399 { "id", PLEDGE_ID }, 400 { "inet", PLEDGE_INET }, 401 { "mcast", PLEDGE_MCAST }, 402 { "pf", PLEDGE_PF }, 403 { "proc", PLEDGE_PROC }, 404 { "prot_exec", PLEDGE_PROTEXEC }, 405 { "ps", PLEDGE_PS }, 406 { "recvfd", PLEDGE_RECVFD }, 407 { "route", PLEDGE_ROUTE }, 408 { "rpath", PLEDGE_RPATH }, 409 { "sendfd", PLEDGE_SENDFD }, 410 { "settime", PLEDGE_SETTIME }, 411 { "stdio", PLEDGE_STDIO }, 412 { "tape", PLEDGE_TAPE }, 413 { "tmppath", PLEDGE_TMPPATH }, 414 { "tty", PLEDGE_TTY }, 415 { "unix", PLEDGE_UNIX }, 416 { "unveil", PLEDGE_UNVEIL }, 417 { "video", PLEDGE_VIDEO }, 418 { "vminfo", PLEDGE_VMINFO }, 419 { "vmm", PLEDGE_VMM }, 420 { "wpath", PLEDGE_WPATH }, 421 { "wroute", PLEDGE_WROUTE }, 422 }; 423 424 int 425 parsepledges(struct proc *p, const char *kname, const char *promises, u_int64_t *fp) 426 { 427 size_t rbuflen; 428 char *rbuf, *rp, *pn; 429 u_int64_t flags = 0, f; 430 int error; 431 432 rbuf = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 433 error = copyinstr(promises, rbuf, MAXPATHLEN, &rbuflen); 434 if (error) { 435 free(rbuf, M_TEMP, MAXPATHLEN); 436 return (error); 437 } 438 #ifdef KTRACE 439 if (KTRPOINT(p, KTR_STRUCT)) 440 ktrstruct(p, kname, rbuf, rbuflen-1); 441 #endif 442 443 for (rp = rbuf; rp && *rp; rp = pn) { 444 pn = strchr(rp, ' '); /* find terminator */ 445 if (pn) { 446 while (*pn == ' ') 447 *pn++ = '\0'; 448 } 449 if ((f = pledgereq_flags(rp)) == 0) { 450 free(rbuf, M_TEMP, MAXPATHLEN); 451 return (EINVAL); 452 } 453 flags |= f; 454 } 455 free(rbuf, M_TEMP, MAXPATHLEN); 456 *fp = flags; 457 return 0; 458 } 459 460 int 461 sys_pledge(struct proc *p, void *v, register_t *retval) 462 { 463 struct sys_pledge_args /* { 464 syscallarg(const char *)promises; 465 syscallarg(const char *)execpromises; 466 } */ *uap = v; 467 struct process *pr = p->p_p; 468 uint64_t promises, execpromises; 469 int error; 470 int unveil_cleanup = 0; 471 472 /* Check for any error in user input */ 473 if (SCARG(uap, promises)) { 474 error = parsepledges(p, "pledgereq", 475 SCARG(uap, promises), &promises); 476 if (error) 477 return (error); 478 } 479 if (SCARG(uap, execpromises)) { 480 error = parsepledges(p, "pledgeexecreq", 481 SCARG(uap, execpromises), &execpromises); 482 if (error) 483 return (error); 484 } 485 486 mtx_enter(&pr->ps_mtx); 487 488 /* Check for any error wrt current promises */ 489 if (SCARG(uap, promises)) { 490 /* In "error" mode, ignore promise increase requests, 491 * but accept promise decrease requests */ 492 if (ISSET(pr->ps_flags, PS_PLEDGE) && 493 (pr->ps_pledge & PLEDGE_ERROR)) 494 promises &= (pr->ps_pledge & PLEDGE_USERSET); 495 496 /* Only permit reductions */ 497 if (ISSET(pr->ps_flags, PS_PLEDGE) && 498 (((promises | pr->ps_pledge) != pr->ps_pledge))) { 499 mtx_leave(&pr->ps_mtx); 500 return (EPERM); 501 } 502 } 503 if (SCARG(uap, execpromises)) { 504 /* Only permit reductions */ 505 if (ISSET(pr->ps_flags, PS_EXECPLEDGE) && 506 (((execpromises | pr->ps_execpledge) != pr->ps_execpledge))) { 507 mtx_leave(&pr->ps_mtx); 508 return (EPERM); 509 } 510 } 511 512 /* Set up promises */ 513 if (SCARG(uap, promises)) { 514 pr->ps_pledge = promises; 515 atomic_setbits_int(&pr->ps_flags, PS_PLEDGE); 516 517 if ((pr->ps_pledge & (PLEDGE_RPATH | PLEDGE_WPATH | 518 PLEDGE_CPATH | PLEDGE_DPATH | PLEDGE_TMPPATH | PLEDGE_EXEC | 519 PLEDGE_UNIX | PLEDGE_UNVEIL)) == 0) 520 unveil_cleanup = 1; 521 } 522 if (SCARG(uap, execpromises)) { 523 pr->ps_execpledge = execpromises; 524 atomic_setbits_int(&pr->ps_flags, PS_EXECPLEDGE); 525 } 526 527 mtx_leave(&pr->ps_mtx); 528 529 if (unveil_cleanup) { 530 /* 531 * Kill off unveil and drop unveil vnode refs if we no 532 * longer are holding any path-accessing pledge 533 */ 534 KERNEL_LOCK(); 535 unveil_destroy(pr); 536 KERNEL_UNLOCK(); 537 } 538 539 return (0); 540 } 541 542 int 543 pledge_syscall(struct proc *p, int code, uint64_t *tval) 544 { 545 p->p_pledge_syscall = code; 546 *tval = 0; 547 548 if (code < 0 || code > SYS_MAXSYSCALL - 1) 549 return (EINVAL); 550 551 if (pledge_syscalls[code] == PLEDGE_ALWAYS) 552 return (0); 553 554 if (p->p_p->ps_pledge & pledge_syscalls[code]) 555 return (0); 556 557 *tval = pledge_syscalls[code]; 558 return (EPERM); 559 } 560 561 int 562 pledge_fail(struct proc *p, int error, uint64_t code) 563 { 564 const char *codes = ""; 565 int i; 566 567 /* Print first matching pledge */ 568 for (i = 0; code && pledgenames[i].bits != 0; i++) 569 if (pledgenames[i].bits & code) { 570 codes = pledgenames[i].name; 571 break; 572 } 573 #ifdef KTRACE 574 if (KTRPOINT(p, KTR_PLEDGE)) 575 ktrpledge(p, error, code, p->p_pledge_syscall); 576 #endif 577 if (p->p_p->ps_pledge & PLEDGE_ERROR) 578 return (ENOSYS); 579 580 KERNEL_LOCK(); 581 log(LOG_ERR, "%s[%d]: pledge \"%s\", syscall %d\n", 582 p->p_p->ps_comm, p->p_p->ps_pid, codes, p->p_pledge_syscall); 583 p->p_p->ps_acflag |= APLEDGE; 584 585 /* Stop threads immediately, because this process is suspect */ 586 if (P_HASSIBLING(p)) 587 single_thread_set(p, SINGLE_SUSPEND, 1); 588 589 /* Send uncatchable SIGABRT for coredump */ 590 sigabort(p); 591 592 p->p_p->ps_pledge = 0; /* Disable all PLEDGE_ flags */ 593 KERNEL_UNLOCK(); 594 return (error); 595 } 596 597 /* 598 * Need to make it more obvious that one cannot get through here 599 * without the right flags set 600 */ 601 int 602 pledge_namei(struct proc *p, struct nameidata *ni, char *origpath) 603 { 604 char path[PATH_MAX]; 605 uint64_t pledge; 606 int error; 607 608 if ((p->p_p->ps_flags & PS_PLEDGE) == 0 || 609 (p->p_p->ps_flags & PS_COREDUMP)) 610 return (0); 611 pledge = READ_ONCE(p->p_p->ps_pledge); 612 613 if (ni->ni_pledge == 0) 614 panic("pledge_namei: ni_pledge"); 615 616 /* 617 * We set the BYPASSUNVEIL flag to skip unveil checks 618 * as necessary 619 */ 620 621 /* Doing a permitted execve() */ 622 if ((ni->ni_pledge & PLEDGE_EXEC) && 623 (pledge & PLEDGE_EXEC)) 624 return (0); 625 626 error = canonpath(origpath, path, sizeof(path)); 627 if (error) 628 return (error); 629 630 /* Detect what looks like a mkstemp(3) family operation */ 631 if ((pledge & PLEDGE_TMPPATH) && 632 (p->p_pledge_syscall == SYS_open) && 633 (ni->ni_pledge & PLEDGE_CPATH) && 634 strncmp(path, "/tmp/", sizeof("/tmp/") - 1) == 0) { 635 ni->ni_cnd.cn_flags |= BYPASSUNVEIL; 636 return (0); 637 } 638 639 /* Allow unlinking of a mkstemp(3) file... 640 * Good opportunity for strict checks here. 641 */ 642 if ((pledge & PLEDGE_TMPPATH) && 643 (p->p_pledge_syscall == SYS_unlink) && 644 strncmp(path, "/tmp/", sizeof("/tmp/") - 1) == 0) { 645 ni->ni_cnd.cn_flags |= BYPASSUNVEIL; 646 return (0); 647 } 648 649 /* Whitelisted paths */ 650 switch (p->p_pledge_syscall) { 651 case SYS_access: 652 /* tzset() needs this. */ 653 if (ni->ni_pledge == PLEDGE_RPATH && 654 strcmp(path, "/etc/localtime") == 0) { 655 ni->ni_cnd.cn_flags |= BYPASSUNVEIL; 656 return (0); 657 } 658 break; 659 case SYS_open: 660 /* daemon(3) or other such functions */ 661 if ((ni->ni_pledge & ~(PLEDGE_RPATH | PLEDGE_WPATH)) == 0 && 662 strcmp(path, "/dev/null") == 0) { 663 ni->ni_cnd.cn_flags |= BYPASSUNVEIL; 664 return (0); 665 } 666 667 /* readpassphrase(3), getpass(3) */ 668 if ((pledge & PLEDGE_TTY) && 669 (ni->ni_pledge & ~(PLEDGE_RPATH | PLEDGE_WPATH)) == 0 && 670 strcmp(path, "/dev/tty") == 0) { 671 ni->ni_cnd.cn_flags |= BYPASSUNVEIL; 672 return (0); 673 } 674 675 /* getpw* and friends need a few files */ 676 if ((ni->ni_pledge == PLEDGE_RPATH) && 677 (pledge & PLEDGE_GETPW)) { 678 if (strcmp(path, "/etc/spwd.db") == 0) 679 return (EPERM); /* don't call pledge_fail */ 680 if (strcmp(path, "/etc/pwd.db") == 0) { 681 ni->ni_cnd.cn_flags |= BYPASSUNVEIL; 682 return (0); 683 } 684 if (strcmp(path, "/etc/group") == 0) { 685 ni->ni_cnd.cn_flags |= BYPASSUNVEIL; 686 return (0); 687 } 688 if (strcmp(path, "/etc/netid") == 0) { 689 ni->ni_cnd.cn_flags |= BYPASSUNVEIL; 690 return (0); 691 } 692 } 693 694 /* DNS needs /etc/{resolv.conf,hosts,services,protocols}. */ 695 if ((ni->ni_pledge == PLEDGE_RPATH) && 696 (pledge & PLEDGE_DNS)) { 697 if (strcmp(path, "/etc/resolv.conf") == 0) { 698 ni->ni_cnd.cn_flags |= BYPASSUNVEIL; 699 return (0); 700 } 701 if (strcmp(path, "/etc/hosts") == 0) { 702 ni->ni_cnd.cn_flags |= BYPASSUNVEIL; 703 return (0); 704 } 705 if (strcmp(path, "/etc/services") == 0) { 706 ni->ni_cnd.cn_flags |= BYPASSUNVEIL; 707 return (0); 708 } 709 if (strcmp(path, "/etc/protocols") == 0) { 710 ni->ni_cnd.cn_flags |= BYPASSUNVEIL; 711 return (0); 712 } 713 } 714 715 /* tzset() needs these. */ 716 if ((ni->ni_pledge == PLEDGE_RPATH) && 717 strncmp(path, "/usr/share/zoneinfo/", 718 sizeof("/usr/share/zoneinfo/") - 1) == 0) { 719 ni->ni_cnd.cn_flags |= BYPASSUNVEIL; 720 return (0); 721 } 722 if ((ni->ni_pledge == PLEDGE_RPATH) && 723 strcmp(path, "/etc/localtime") == 0) { 724 ni->ni_cnd.cn_flags |= BYPASSUNVEIL; 725 return (0); 726 } 727 728 break; 729 case SYS_stat: 730 /* DNS needs /etc/{resolv.conf,hosts}. */ 731 if ((ni->ni_pledge == PLEDGE_RPATH) && 732 (pledge & PLEDGE_DNS)) { 733 if (strcmp(path, "/etc/resolv.conf") == 0) { 734 ni->ni_cnd.cn_flags |= BYPASSUNVEIL; 735 return (0); 736 } 737 if (strcmp(path, "/etc/hosts") == 0) { 738 ni->ni_cnd.cn_flags |= BYPASSUNVEIL; 739 return (0); 740 } 741 } 742 break; 743 } 744 745 /* 746 * Ensure each flag of ni_pledge has counterpart allowing it in 747 * ps_pledge. 748 */ 749 if (ni->ni_pledge & ~pledge) 750 return (pledge_fail(p, EPERM, (ni->ni_pledge & ~pledge))); 751 752 /* continue, and check unveil if present */ 753 return (0); 754 } 755 756 /* 757 * Only allow reception of safe file descriptors. 758 */ 759 int 760 pledge_recvfd(struct proc *p, struct file *fp) 761 { 762 struct vnode *vp; 763 764 if ((p->p_p->ps_flags & PS_PLEDGE) == 0) 765 return (0); 766 if ((p->p_p->ps_pledge & PLEDGE_RECVFD) == 0) 767 return pledge_fail(p, EPERM, PLEDGE_RECVFD); 768 769 switch (fp->f_type) { 770 case DTYPE_SOCKET: 771 case DTYPE_PIPE: 772 case DTYPE_DMABUF: 773 case DTYPE_SYNC: 774 return (0); 775 case DTYPE_VNODE: 776 vp = fp->f_data; 777 778 if (vp->v_type != VDIR) 779 return (0); 780 } 781 return pledge_fail(p, EINVAL, PLEDGE_RECVFD); 782 } 783 784 /* 785 * Only allow sending of safe file descriptors. 786 */ 787 int 788 pledge_sendfd(struct proc *p, struct file *fp) 789 { 790 struct vnode *vp; 791 792 if ((p->p_p->ps_flags & PS_PLEDGE) == 0) 793 return (0); 794 if ((p->p_p->ps_pledge & PLEDGE_SENDFD) == 0) 795 return pledge_fail(p, EPERM, PLEDGE_SENDFD); 796 797 switch (fp->f_type) { 798 case DTYPE_SOCKET: 799 case DTYPE_PIPE: 800 case DTYPE_DMABUF: 801 case DTYPE_SYNC: 802 return (0); 803 case DTYPE_VNODE: 804 vp = fp->f_data; 805 806 if (vp->v_type != VDIR) 807 return (0); 808 break; 809 } 810 return pledge_fail(p, EINVAL, PLEDGE_SENDFD); 811 } 812 813 int 814 pledge_sysctl(struct proc *p, int miblen, int *mib, void *new) 815 { 816 char buf[80]; 817 uint64_t pledge; 818 int i; 819 820 if ((p->p_p->ps_flags & PS_PLEDGE) == 0) 821 return (0); 822 pledge = READ_ONCE(p->p_p->ps_pledge); 823 824 if (new) 825 return pledge_fail(p, EFAULT, 0); 826 827 /* routing table observation */ 828 if ((pledge & PLEDGE_ROUTE)) { 829 if ((miblen == 6 || miblen == 7) && 830 mib[0] == CTL_NET && mib[1] == PF_ROUTE && 831 mib[2] == 0 && 832 mib[4] == NET_RT_DUMP) 833 return (0); 834 835 if (miblen == 6 && 836 mib[0] == CTL_NET && mib[1] == PF_ROUTE && 837 mib[2] == 0 && 838 (mib[3] == 0 || mib[3] == AF_INET6 || mib[3] == AF_INET) && 839 (mib[4] == NET_RT_TABLE || mib[4] == NET_RT_SOURCE)) 840 return (0); 841 842 if (miblen == 7 && /* exposes MACs */ 843 mib[0] == CTL_NET && mib[1] == PF_ROUTE && 844 mib[2] == 0 && 845 (mib[3] == 0 || mib[3] == AF_INET6 || mib[3] == AF_INET) && 846 mib[4] == NET_RT_FLAGS && mib[5] == RTF_LLINFO) 847 return (0); 848 } 849 850 if ((pledge & PLEDGE_WROUTE)) { 851 if (miblen == 4 && 852 mib[0] == CTL_NET && mib[1] == PF_INET6 && 853 mib[2] == IPPROTO_IPV6 && mib[3] == IPV6CTL_SOIIKEY) 854 return (0); 855 } 856 857 if (pledge & (PLEDGE_PS | PLEDGE_VMINFO)) { 858 if (miblen == 2 && /* kern.fscale */ 859 mib[0] == CTL_KERN && mib[1] == KERN_FSCALE) 860 return (0); 861 if (miblen == 2 && /* kern.boottime */ 862 mib[0] == CTL_KERN && mib[1] == KERN_BOOTTIME) 863 return (0); 864 if (miblen == 2 && /* kern.consdev */ 865 mib[0] == CTL_KERN && mib[1] == KERN_CONSDEV) 866 return (0); 867 if (miblen == 2 && /* kern.cptime */ 868 mib[0] == CTL_KERN && mib[1] == KERN_CPTIME) 869 return (0); 870 if (miblen == 3 && /* kern.cptime2 */ 871 mib[0] == CTL_KERN && mib[1] == KERN_CPTIME2) 872 return (0); 873 if (miblen == 3 && /* kern.cpustats */ 874 mib[0] == CTL_KERN && mib[1] == KERN_CPUSTATS) 875 return (0); 876 } 877 878 if ((pledge & PLEDGE_PS)) { 879 if (miblen == 4 && /* kern.procargs.* */ 880 mib[0] == CTL_KERN && mib[1] == KERN_PROC_ARGS && 881 (mib[3] == KERN_PROC_ARGV || mib[3] == KERN_PROC_ENV)) 882 return (0); 883 if (miblen == 6 && /* kern.proc.* */ 884 mib[0] == CTL_KERN && mib[1] == KERN_PROC) 885 return (0); 886 if (miblen == 3 && /* kern.proc_cwd.* */ 887 mib[0] == CTL_KERN && mib[1] == KERN_PROC_CWD) 888 return (0); 889 if (miblen == 2 && /* kern.ccpu */ 890 mib[0] == CTL_KERN && mib[1] == KERN_CCPU) 891 return (0); 892 if (miblen == 2 && /* vm.maxslp */ 893 mib[0] == CTL_VM && mib[1] == VM_MAXSLP) 894 return (0); 895 } 896 897 if ((pledge & PLEDGE_VMINFO)) { 898 if (miblen == 2 && /* vm.uvmexp */ 899 mib[0] == CTL_VM && mib[1] == VM_UVMEXP) 900 return (0); 901 if (miblen == 3 && /* vfs.generic.bcachestat */ 902 mib[0] == CTL_VFS && mib[1] == VFS_GENERIC && 903 mib[2] == VFS_BCACHESTAT) 904 return (0); 905 if (miblen == 3 && /* for sysconf(3) */ 906 mib[0] == CTL_NET && mib[1] == PF_INET6) 907 return (0); 908 } 909 910 if ((pledge & (PLEDGE_INET | PLEDGE_UNIX))) { 911 if (miblen == 2 && /* kern.somaxconn */ 912 mib[0] == CTL_KERN && mib[1] == KERN_SOMAXCONN) 913 return (0); 914 } 915 916 if ((pledge & (PLEDGE_ROUTE | PLEDGE_INET | PLEDGE_DNS))) { 917 if (miblen == 6 && /* getifaddrs() */ 918 mib[0] == CTL_NET && mib[1] == PF_ROUTE && 919 mib[2] == 0 && 920 (mib[3] == 0 || mib[3] == AF_INET6 || mib[3] == AF_INET) && 921 mib[4] == NET_RT_IFLIST) 922 return (0); 923 } 924 925 if ((pledge & PLEDGE_DISKLABEL)) { 926 if (miblen == 2 && /* kern.rawpartition */ 927 mib[0] == CTL_KERN && 928 mib[1] == KERN_RAWPARTITION) 929 return (0); 930 if (miblen == 2 && /* kern.maxpartitions */ 931 mib[0] == CTL_KERN && 932 mib[1] == KERN_MAXPARTITIONS) 933 return (0); 934 #ifdef CPU_CHR2BLK 935 if (miblen == 3 && /* machdep.chr2blk */ 936 mib[0] == CTL_MACHDEP && 937 mib[1] == CPU_CHR2BLK) 938 return (0); 939 #endif /* CPU_CHR2BLK */ 940 } 941 942 if (miblen >= 3 && /* ntpd(8) to read sensors */ 943 mib[0] == CTL_HW && mib[1] == HW_SENSORS) 944 return (0); 945 946 if (miblen == 6 && /* if_nameindex() */ 947 mib[0] == CTL_NET && mib[1] == PF_ROUTE && 948 mib[2] == 0 && mib[3] == 0 && mib[4] == NET_RT_IFNAMES) 949 return (0); 950 951 if (miblen == 2) { 952 switch (mib[0]) { 953 case CTL_KERN: 954 switch (mib[1]) { 955 case KERN_DOMAINNAME: /* getdomainname() */ 956 case KERN_HOSTNAME: /* gethostname() */ 957 case KERN_OSTYPE: /* uname() */ 958 case KERN_OSRELEASE: /* uname() */ 959 case KERN_OSVERSION: /* uname() */ 960 case KERN_VERSION: /* uname() */ 961 case KERN_CLOCKRATE: /* kern.clockrate */ 962 case KERN_ARGMAX: /* kern.argmax */ 963 case KERN_NGROUPS: /* kern.ngroups */ 964 case KERN_SYSVSHM: /* kern.sysvshm */ 965 case KERN_POSIX1: /* kern.posix1version */ 966 case KERN_AUTOCONF_SERIAL: /* kern.autoconf_serial */ 967 return (0); 968 } 969 break; 970 case CTL_HW: 971 switch (mib[1]) { 972 case HW_MACHINE: /* uname() */ 973 case HW_PAGESIZE: /* getpagesize() */ 974 case HW_PHYSMEM64: /* hw.physmem */ 975 case HW_NCPU: /* hw.ncpu */ 976 case HW_NCPUONLINE: /* hw.ncpuonline */ 977 case HW_USERMEM64: /* hw.usermem */ 978 return (0); 979 } 980 break; 981 case CTL_VM: 982 switch (mib[1]) { 983 case VM_PSSTRINGS: /* setproctitle() */ 984 case VM_LOADAVG: /* vm.loadavg / getloadavg(3) */ 985 case VM_MALLOC_CONF: /* vm.malloc_conf */ 986 return (0); 987 } 988 break; 989 default: 990 break; 991 } 992 } 993 994 #ifdef CPU_SSE 995 if (miblen == 2 && /* i386 libm tests for SSE */ 996 mib[0] == CTL_MACHDEP && mib[1] == CPU_SSE) 997 return (0); 998 #endif /* CPU_SSE */ 999 1000 #ifdef CPU_ID_AA64ISAR0 1001 if (miblen == 2 && /* arm64 libcrypto inspects CPU features */ 1002 mib[0] == CTL_MACHDEP && mib[1] == CPU_ID_AA64ISAR0) 1003 return (0); 1004 #endif /* CPU_ID_AA64ISAR0 */ 1005 1006 snprintf(buf, sizeof(buf), "%s(%d): pledge sysctl %d:", 1007 p->p_p->ps_comm, p->p_p->ps_pid, miblen); 1008 for (i = 0; i < miblen; i++) { 1009 char *p = buf + strlen(buf); 1010 snprintf(p, sizeof(buf) - (p - buf), " %d", mib[i]); 1011 } 1012 log(LOG_ERR, "%s\n", buf); 1013 1014 return pledge_fail(p, EINVAL, 0); 1015 } 1016 1017 int 1018 pledge_chown(struct proc *p, uid_t uid, gid_t gid) 1019 { 1020 if ((p->p_p->ps_flags & PS_PLEDGE) == 0) 1021 return (0); 1022 1023 if (p->p_p->ps_pledge & PLEDGE_CHOWNUID) 1024 return (0); 1025 1026 if (uid != -1 && uid != p->p_ucred->cr_uid) 1027 return (EPERM); 1028 if (gid != -1 && !groupmember(gid, p->p_ucred)) 1029 return (EPERM); 1030 return (0); 1031 } 1032 1033 int 1034 pledge_adjtime(struct proc *p, const void *v) 1035 { 1036 const struct timeval *delta = v; 1037 1038 if ((p->p_p->ps_flags & PS_PLEDGE) == 0) 1039 return (0); 1040 1041 if ((p->p_p->ps_pledge & PLEDGE_SETTIME)) 1042 return (0); 1043 if (delta) 1044 return (EPERM); 1045 return (0); 1046 } 1047 1048 int 1049 pledge_sendit(struct proc *p, const void *to) 1050 { 1051 if ((p->p_p->ps_flags & PS_PLEDGE) == 0) 1052 return (0); 1053 1054 if ((p->p_p->ps_pledge & (PLEDGE_INET | PLEDGE_UNIX | PLEDGE_DNS))) 1055 return (0); /* may use address */ 1056 if (to == NULL) 1057 return (0); /* behaves just like write */ 1058 return pledge_fail(p, EPERM, PLEDGE_INET); 1059 } 1060 1061 int 1062 pledge_ioctl(struct proc *p, long com, struct file *fp) 1063 { 1064 struct vnode *vp = NULL; 1065 int error = EPERM; 1066 uint64_t pledge; 1067 1068 if ((p->p_p->ps_flags & PS_PLEDGE) == 0) 1069 return (0); 1070 pledge = READ_ONCE(p->p_p->ps_pledge); 1071 1072 /* 1073 * The ioctl's which are always allowed. 1074 */ 1075 switch (com) { 1076 case FIONREAD: 1077 case FIONBIO: 1078 case FIOCLEX: 1079 case FIONCLEX: 1080 return (0); 1081 } 1082 1083 /* fp != NULL was already checked */ 1084 if (fp->f_type == DTYPE_VNODE) { 1085 vp = fp->f_data; 1086 if (vp->v_type == VBAD) 1087 return (ENOTTY); 1088 } 1089 1090 if ((pledge & PLEDGE_INET)) { 1091 switch (com) { 1092 case SIOCATMARK: 1093 case SIOCGIFGROUP: 1094 if (fp->f_type == DTYPE_SOCKET) 1095 return (0); 1096 break; 1097 } 1098 } 1099 1100 #if NBPFILTER > 0 1101 if ((pledge & PLEDGE_BPF)) { 1102 switch (com) { 1103 case BIOCGSTATS: /* bpf: tcpdump privsep on ^C */ 1104 if (fp->f_type == DTYPE_VNODE && 1105 fp->f_ops->fo_ioctl == vn_ioctl && 1106 vp->v_type == VCHR && 1107 cdevsw[major(vp->v_rdev)].d_open == bpfopen) 1108 return (0); 1109 break; 1110 } 1111 } 1112 #endif /* NBPFILTER > 0 */ 1113 1114 if ((pledge & PLEDGE_TAPE)) { 1115 switch (com) { 1116 case MTIOCGET: 1117 case MTIOCTOP: 1118 /* for pax(1) and such, checking tapes... */ 1119 if (fp->f_type == DTYPE_VNODE && 1120 vp->v_type == VCHR) { 1121 if (vp->v_flag & VISTTY) 1122 return (ENOTTY); 1123 else 1124 return (0); 1125 } 1126 break; 1127 } 1128 } 1129 1130 #if NDRM > 0 1131 if ((pledge & PLEDGE_DRM)) { 1132 if ((fp->f_type == DTYPE_VNODE) && 1133 (vp->v_type == VCHR) && 1134 (cdevsw[major(vp->v_rdev)].d_open == drmopen)) { 1135 error = pledge_ioctl_drm(p, com, vp->v_rdev); 1136 if (error == 0) 1137 return 0; 1138 } 1139 } 1140 #endif /* NDRM > 0 */ 1141 1142 #if NAUDIO > 0 1143 if ((pledge & PLEDGE_AUDIO)) { 1144 switch (com) { 1145 case AUDIO_GETPOS: 1146 case AUDIO_GETPAR: 1147 case AUDIO_SETPAR: 1148 case AUDIO_START: 1149 case AUDIO_STOP: 1150 case AUDIO_MIXER_DEVINFO: 1151 case AUDIO_MIXER_READ: 1152 case AUDIO_MIXER_WRITE: 1153 if (fp->f_type == DTYPE_VNODE && 1154 vp->v_type == VCHR && 1155 cdevsw[major(vp->v_rdev)].d_open == audioopen) 1156 return (0); 1157 } 1158 } 1159 #endif /* NAUDIO > 0 */ 1160 1161 if ((pledge & PLEDGE_DISKLABEL)) { 1162 switch (com) { 1163 case DIOCGDINFO: 1164 case DIOCGPDINFO: 1165 case DIOCRLDINFO: 1166 case DIOCWDINFO: 1167 case BIOCDISK: 1168 case BIOCINQ: 1169 case BIOCINSTALLBOOT: 1170 case BIOCVOL: 1171 if (fp->f_type == DTYPE_VNODE && 1172 ((vp->v_type == VCHR && 1173 cdevsw[major(vp->v_rdev)].d_type == D_DISK) || 1174 (vp->v_type == VBLK && 1175 bdevsw[major(vp->v_rdev)].d_type == D_DISK))) 1176 return (0); 1177 break; 1178 case DIOCMAP: 1179 if (fp->f_type == DTYPE_VNODE && 1180 vp->v_type == VCHR && 1181 cdevsw[major(vp->v_rdev)].d_ioctl == diskmapioctl) 1182 return (0); 1183 break; 1184 } 1185 } 1186 1187 #if NVIDEO > 0 1188 if ((pledge & PLEDGE_VIDEO)) { 1189 switch (com) { 1190 case VIDIOC_QUERYCAP: 1191 case VIDIOC_TRY_FMT: 1192 case VIDIOC_ENUM_FMT: 1193 case VIDIOC_S_FMT: 1194 case VIDIOC_QUERYCTRL: 1195 case VIDIOC_G_CTRL: 1196 case VIDIOC_S_CTRL: 1197 case VIDIOC_G_PARM: 1198 case VIDIOC_S_PARM: 1199 case VIDIOC_REQBUFS: 1200 case VIDIOC_QBUF: 1201 case VIDIOC_DQBUF: 1202 case VIDIOC_QUERYBUF: 1203 case VIDIOC_STREAMON: 1204 case VIDIOC_STREAMOFF: 1205 case VIDIOC_ENUM_FRAMESIZES: 1206 case VIDIOC_ENUM_FRAMEINTERVALS: 1207 case VIDIOC_DQEVENT: 1208 case VIDIOC_ENCODER_CMD: 1209 case VIDIOC_EXPBUF: 1210 case VIDIOC_G_CROP: 1211 case VIDIOC_G_EXT_CTRLS: 1212 case VIDIOC_G_FMT: 1213 case VIDIOC_G_SELECTION: 1214 case VIDIOC_QUERYMENU: 1215 case VIDIOC_SUBSCRIBE_EVENT: 1216 case VIDIOC_S_EXT_CTRLS: 1217 case VIDIOC_S_SELECTION: 1218 case VIDIOC_TRY_DECODER_CMD: 1219 case VIDIOC_TRY_ENCODER_CMD: 1220 if (fp->f_type == DTYPE_VNODE && 1221 vp->v_type == VCHR && 1222 cdevsw[major(vp->v_rdev)].d_open == videoopen) 1223 return (0); 1224 break; 1225 } 1226 } 1227 #endif 1228 1229 #if NPF > 0 1230 if ((pledge & PLEDGE_PF)) { 1231 switch (com) { 1232 case DIOCADDRULE: 1233 case DIOCGETSTATUS: 1234 case DIOCNATLOOK: 1235 case DIOCRADDTABLES: 1236 case DIOCRCLRADDRS: 1237 case DIOCRCLRTABLES: 1238 case DIOCRCLRTSTATS: 1239 case DIOCRGETTSTATS: 1240 case DIOCRSETADDRS: 1241 case DIOCXBEGIN: 1242 case DIOCXCOMMIT: 1243 case DIOCKILLSRCNODES: 1244 if ((fp->f_type == DTYPE_VNODE) && 1245 (vp->v_type == VCHR) && 1246 (cdevsw[major(vp->v_rdev)].d_open == pfopen)) 1247 return (0); 1248 break; 1249 } 1250 } 1251 #endif 1252 1253 if ((pledge & PLEDGE_TTY)) { 1254 switch (com) { 1255 #if NPTY > 0 1256 case PTMGET: 1257 if ((pledge & PLEDGE_RPATH) == 0) 1258 break; 1259 if ((pledge & PLEDGE_WPATH) == 0) 1260 break; 1261 if (fp->f_type != DTYPE_VNODE || vp->v_type != VCHR) 1262 break; 1263 if (cdevsw[major(vp->v_rdev)].d_open != ptmopen) 1264 break; 1265 return (0); 1266 case TIOCUCNTL: /* vmd */ 1267 if ((pledge & PLEDGE_RPATH) == 0) 1268 break; 1269 if ((pledge & PLEDGE_WPATH) == 0) 1270 break; 1271 if (cdevsw[major(vp->v_rdev)].d_open != ptcopen) 1272 break; 1273 return (0); 1274 #endif /* NPTY > 0 */ 1275 case TIOCSPGRP: 1276 if ((pledge & PLEDGE_PROC) == 0) 1277 break; 1278 /* FALLTHROUGH */ 1279 case TIOCFLUSH: /* getty, telnet */ 1280 case TIOCSTART: /* emacs, etc */ 1281 case TIOCGPGRP: 1282 case TIOCGETA: 1283 case TIOCGWINSZ: /* ENOTTY return for non-tty */ 1284 case TIOCSTAT: /* csh */ 1285 if (fp->f_type == DTYPE_VNODE && (vp->v_flag & VISTTY)) 1286 return (0); 1287 return (ENOTTY); 1288 case TIOCSWINSZ: 1289 case TIOCEXT: /* mail, libedit .. */ 1290 case TIOCCBRK: /* cu */ 1291 case TIOCSBRK: /* cu */ 1292 case TIOCCDTR: /* cu */ 1293 case TIOCSDTR: /* cu */ 1294 case TIOCEXCL: /* cu */ 1295 case TIOCSETA: /* cu, ... */ 1296 case TIOCSETAW: /* cu, ... */ 1297 case TIOCSETAF: /* tcsetattr TCSAFLUSH, script */ 1298 case TIOCSCTTY: /* forkpty(3), login_tty(3), ... */ 1299 if (fp->f_type == DTYPE_VNODE && (vp->v_flag & VISTTY)) 1300 return (0); 1301 break; 1302 } 1303 } 1304 1305 if ((pledge & PLEDGE_ROUTE)) { 1306 switch (com) { 1307 case SIOCGIFADDR: 1308 case SIOCGIFAFLAG_IN6: 1309 case SIOCGIFALIFETIME_IN6: 1310 case SIOCGIFDESCR: 1311 case SIOCGIFFLAGS: 1312 case SIOCGIFMETRIC: 1313 case SIOCGIFGMEMB: 1314 case SIOCGIFRDOMAIN: 1315 case SIOCGIFDSTADDR_IN6: 1316 case SIOCGIFNETMASK_IN6: 1317 case SIOCGIFXFLAGS: 1318 case SIOCGNBRINFO_IN6: 1319 case SIOCGIFINFO_IN6: 1320 case SIOCGIFMEDIA: 1321 if (fp->f_type == DTYPE_SOCKET) 1322 return (0); 1323 break; 1324 } 1325 } 1326 1327 if ((pledge & PLEDGE_WROUTE)) { 1328 switch (com) { 1329 case SIOCAIFADDR: 1330 case SIOCDIFADDR: 1331 case SIOCAIFADDR_IN6: 1332 case SIOCDIFADDR_IN6: 1333 if (fp->f_type == DTYPE_SOCKET) 1334 return (0); 1335 break; 1336 case SIOCSIFMTU: 1337 if (fp->f_type == DTYPE_SOCKET) 1338 return (0); 1339 break; 1340 } 1341 } 1342 1343 #if NVMM > 0 1344 if ((pledge & PLEDGE_VMM)) { 1345 if ((fp->f_type == DTYPE_VNODE) && 1346 (vp->v_type == VCHR) && 1347 (cdevsw[major(vp->v_rdev)].d_open == vmmopen)) { 1348 error = pledge_ioctl_vmm(p, com); 1349 if (error == 0) 1350 return 0; 1351 } 1352 } 1353 #endif 1354 1355 return pledge_fail(p, error, PLEDGE_TTY); 1356 } 1357 1358 int 1359 pledge_sockopt(struct proc *p, int set, int level, int optname) 1360 { 1361 uint64_t pledge; 1362 1363 if ((p->p_p->ps_flags & PS_PLEDGE) == 0) 1364 return (0); 1365 pledge = READ_ONCE(p->p_p->ps_pledge); 1366 1367 /* Always allow these, which are too common to reject */ 1368 switch (level) { 1369 case SOL_SOCKET: 1370 switch (optname) { 1371 case SO_RCVBUF: 1372 case SO_ERROR: 1373 return (0); 1374 } 1375 break; 1376 case IPPROTO_TCP: 1377 switch (optname) { 1378 case TCP_NODELAY: 1379 return (0); 1380 } 1381 break; 1382 } 1383 1384 if ((pledge & PLEDGE_WROUTE)) { 1385 switch (level) { 1386 case SOL_SOCKET: 1387 switch (optname) { 1388 case SO_RTABLE: 1389 return (0); 1390 } 1391 } 1392 } 1393 1394 if ((pledge & (PLEDGE_INET|PLEDGE_UNIX|PLEDGE_DNS)) == 0) 1395 return pledge_fail(p, EPERM, PLEDGE_INET); 1396 /* In use by some service libraries */ 1397 switch (level) { 1398 case SOL_SOCKET: 1399 switch (optname) { 1400 case SO_TIMESTAMP: 1401 return (0); 1402 } 1403 break; 1404 } 1405 1406 /* DNS resolver may do these requests */ 1407 if ((pledge & PLEDGE_DNS)) { 1408 switch (level) { 1409 case IPPROTO_IPV6: 1410 switch (optname) { 1411 case IPV6_RECVPKTINFO: 1412 case IPV6_USE_MIN_MTU: 1413 return (0); 1414 } 1415 } 1416 } 1417 1418 if ((pledge & (PLEDGE_INET|PLEDGE_UNIX)) == 0) 1419 return pledge_fail(p, EPERM, PLEDGE_INET); 1420 switch (level) { 1421 case SOL_SOCKET: 1422 switch (optname) { 1423 case SO_RTABLE: 1424 return pledge_fail(p, EINVAL, PLEDGE_WROUTE); 1425 } 1426 return (0); 1427 } 1428 1429 if ((pledge & PLEDGE_INET) == 0) 1430 return pledge_fail(p, EPERM, PLEDGE_INET); 1431 switch (level) { 1432 case IPPROTO_TCP: 1433 switch (optname) { 1434 case TCP_MD5SIG: 1435 case TCP_SACK_ENABLE: 1436 case TCP_MAXSEG: 1437 case TCP_NOPUSH: 1438 case TCP_INFO: 1439 return (0); 1440 } 1441 break; 1442 case IPPROTO_IP: 1443 switch (optname) { 1444 case IP_OPTIONS: 1445 if (!set) 1446 return (0); 1447 break; 1448 case IP_TOS: 1449 case IP_TTL: 1450 case IP_MINTTL: 1451 case IP_IPDEFTTL: 1452 case IP_PORTRANGE: 1453 case IP_RECVDSTADDR: 1454 case IP_RECVDSTPORT: 1455 return (0); 1456 case IP_MULTICAST_IF: 1457 case IP_MULTICAST_TTL: 1458 case IP_MULTICAST_LOOP: 1459 case IP_ADD_MEMBERSHIP: 1460 case IP_DROP_MEMBERSHIP: 1461 if (pledge & PLEDGE_MCAST) 1462 return (0); 1463 break; 1464 } 1465 break; 1466 case IPPROTO_ICMP: 1467 break; 1468 case IPPROTO_IPV6: 1469 switch (optname) { 1470 case IPV6_TCLASS: 1471 case IPV6_UNICAST_HOPS: 1472 case IPV6_MINHOPCOUNT: 1473 case IPV6_RECVHOPLIMIT: 1474 case IPV6_PORTRANGE: 1475 case IPV6_RECVPKTINFO: 1476 case IPV6_RECVDSTPORT: 1477 case IPV6_V6ONLY: 1478 return (0); 1479 case IPV6_MULTICAST_IF: 1480 case IPV6_MULTICAST_HOPS: 1481 case IPV6_MULTICAST_LOOP: 1482 case IPV6_JOIN_GROUP: 1483 case IPV6_LEAVE_GROUP: 1484 if (pledge & PLEDGE_MCAST) 1485 return (0); 1486 break; 1487 } 1488 break; 1489 case IPPROTO_ICMPV6: 1490 break; 1491 } 1492 return pledge_fail(p, EPERM, PLEDGE_INET); 1493 } 1494 1495 int 1496 pledge_socket(struct proc *p, int domain, unsigned int state) 1497 { 1498 uint64_t pledge; 1499 1500 if (!ISSET(p->p_p->ps_flags, PS_PLEDGE)) 1501 return 0; 1502 pledge = READ_ONCE(p->p_p->ps_pledge); 1503 1504 if (ISSET(state, SS_DNS)) { 1505 if (ISSET(pledge, PLEDGE_DNS)) 1506 return 0; 1507 return pledge_fail(p, EPERM, PLEDGE_DNS); 1508 } 1509 1510 switch (domain) { 1511 case -1: /* accept on any domain */ 1512 return (0); 1513 case AF_INET: 1514 case AF_INET6: 1515 if (ISSET(pledge, PLEDGE_INET)) 1516 return 0; 1517 return pledge_fail(p, EPERM, PLEDGE_INET); 1518 1519 case AF_UNIX: 1520 if (ISSET(pledge, PLEDGE_UNIX)) 1521 return 0; 1522 return pledge_fail(p, EPERM, PLEDGE_UNIX); 1523 } 1524 1525 return pledge_fail(p, EINVAL, PLEDGE_INET); 1526 } 1527 1528 int 1529 pledge_flock(struct proc *p) 1530 { 1531 if ((p->p_p->ps_flags & PS_PLEDGE) == 0) 1532 return (0); 1533 1534 if ((p->p_p->ps_pledge & PLEDGE_FLOCK)) 1535 return (0); 1536 return (pledge_fail(p, EPERM, PLEDGE_FLOCK)); 1537 } 1538 1539 int 1540 pledge_swapctl(struct proc *p, int cmd) 1541 { 1542 if ((p->p_p->ps_flags & PS_PLEDGE) == 0) 1543 return (0); 1544 1545 if (p->p_p->ps_pledge & PLEDGE_VMINFO) { 1546 switch (cmd) { 1547 case SWAP_NSWAP: 1548 case SWAP_STATS: 1549 return (0); 1550 } 1551 } 1552 1553 return pledge_fail(p, EPERM, PLEDGE_VMINFO); 1554 } 1555 1556 /* bsearch over pledgereq. return flags value if found, 0 else */ 1557 uint64_t 1558 pledgereq_flags(const char *req_name) 1559 { 1560 int base = 0, cmp, i, lim; 1561 1562 for (lim = nitems(pledgereq); lim != 0; lim >>= 1) { 1563 i = base + (lim >> 1); 1564 cmp = strcmp(req_name, pledgereq[i].name); 1565 if (cmp == 0) 1566 return (pledgereq[i].flags); 1567 if (cmp > 0) { /* not found before, move right */ 1568 base = i + 1; 1569 lim--; 1570 } /* else move left */ 1571 } 1572 return (0); 1573 } 1574 1575 int 1576 pledge_fcntl(struct proc *p, int cmd) 1577 { 1578 if ((p->p_p->ps_flags & PS_PLEDGE) == 0) 1579 return (0); 1580 if ((p->p_p->ps_pledge & PLEDGE_PROC) == 0 && cmd == F_SETOWN) 1581 return pledge_fail(p, EPERM, PLEDGE_PROC); 1582 return (0); 1583 } 1584 1585 int 1586 pledge_kill(struct proc *p, pid_t pid) 1587 { 1588 if ((p->p_p->ps_flags & PS_PLEDGE) == 0) 1589 return 0; 1590 if (p->p_p->ps_pledge & PLEDGE_PROC) 1591 return 0; 1592 if (pid == 0 || pid == p->p_p->ps_pid) 1593 return 0; 1594 return pledge_fail(p, EPERM, PLEDGE_PROC); 1595 } 1596 1597 int 1598 pledge_protexec(struct proc *p, int prot) 1599 { 1600 if ((p->p_p->ps_flags & PS_PLEDGE) == 0) 1601 return 0; 1602 /* Before kbind(2) call, ld.so and crt may create EXEC mappings */ 1603 if (p->p_p->ps_kbind_addr == 0 && p->p_p->ps_kbind_cookie == 0) 1604 return 0; 1605 if (!(p->p_p->ps_pledge & PLEDGE_PROTEXEC) && (prot & PROT_EXEC)) 1606 return pledge_fail(p, EPERM, PLEDGE_PROTEXEC); 1607 return 0; 1608 } 1609 1610 int 1611 canonpath(const char *input, char *buf, size_t bufsize) 1612 { 1613 const char *p; 1614 char *q; 1615 1616 /* can't canon relative paths, don't bother */ 1617 if (input[0] != '/') { 1618 if (strlcpy(buf, input, bufsize) >= bufsize) 1619 return ENAMETOOLONG; 1620 return 0; 1621 } 1622 1623 p = input; 1624 q = buf; 1625 while (*p && (q - buf < bufsize)) { 1626 if (p[0] == '/' && (p[1] == '/' || p[1] == '\0')) { 1627 p += 1; 1628 1629 } else if (p[0] == '/' && p[1] == '.' && 1630 (p[2] == '/' || p[2] == '\0')) { 1631 p += 2; 1632 1633 } else if (p[0] == '/' && p[1] == '.' && p[2] == '.' && 1634 (p[3] == '/' || p[3] == '\0')) { 1635 p += 3; 1636 if (q != buf) /* "/../" at start of buf */ 1637 while (*--q != '/') 1638 continue; 1639 1640 } else { 1641 *q++ = *p++; 1642 } 1643 } 1644 if ((*p == '\0') && (q - buf < bufsize)) { 1645 *q = 0; 1646 return 0; 1647 } else 1648 return ENAMETOOLONG; 1649 } 1650