1 /* $OpenBSD: kern_pledge.c,v 1.281 2022/03/25 17:40:59 robert 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 22 #include <sys/mount.h> 23 #include <sys/proc.h> 24 #include <sys/fcntl.h> 25 #include <sys/file.h> 26 #include <sys/filedesc.h> 27 #include <sys/namei.h> 28 #include <sys/pool.h> 29 #include <sys/socketvar.h> 30 #include <sys/vnode.h> 31 #include <sys/mbuf.h> 32 #include <sys/mman.h> 33 #include <sys/sysctl.h> 34 #include <sys/syslog.h> 35 #include <sys/ktrace.h> 36 #include <sys/acct.h> 37 38 #include <sys/ioctl.h> 39 #include <sys/termios.h> 40 #include <sys/tty.h> 41 #include <sys/device.h> 42 #include <sys/disklabel.h> 43 #include <sys/dkio.h> 44 #include <sys/mtio.h> 45 #include <sys/audioio.h> 46 #include <sys/videoio.h> 47 #include <net/bpf.h> 48 #include <net/route.h> 49 #include <net/if.h> 50 #include <net/if_var.h> 51 #include <netinet/in.h> 52 #include <netinet6/in6_var.h> 53 #include <netinet6/nd6.h> 54 #include <netinet/tcp.h> 55 #include <net/pfvar.h> 56 57 #include <sys/conf.h> 58 #include <sys/specdev.h> 59 #include <sys/signal.h> 60 #include <sys/signalvar.h> 61 #include <sys/syscall.h> 62 #include <sys/syscallargs.h> 63 #include <sys/systm.h> 64 65 #include <dev/biovar.h> 66 67 #define PLEDGENAMES 68 #include <sys/pledge.h> 69 70 #include "audio.h" 71 #include "bpfilter.h" 72 #include "pf.h" 73 #include "video.h" 74 #include "pty.h" 75 76 #if defined(__amd64__) 77 #include "vmm.h" 78 #if NVMM > 0 79 #include <machine/conf.h> 80 #endif 81 #endif 82 83 #include "drm.h" 84 85 uint64_t pledgereq_flags(const char *req); 86 int parsepledges(struct proc *p, const char *kname, 87 const char *promises, u_int64_t *fp); 88 int canonpath(const char *input, char *buf, size_t bufsize); 89 void unveil_destroy(struct process *ps); 90 91 /* #define DEBUG_PLEDGE */ 92 #ifdef DEBUG_PLEDGE 93 int debug_pledge = 1; 94 #define DPRINTF(x...) do { if (debug_pledge) printf(x); } while (0) 95 #define DNPRINTF(n,x...) do { if (debug_pledge >= (n)) printf(x); } while (0) 96 #else 97 #define DPRINTF(x...) 98 #define DNPRINTF(n,x...) 99 #endif 100 101 /* 102 * Ordered in blocks starting with least risky and most required. 103 */ 104 const uint64_t pledge_syscalls[SYS_MAXSYSCALL] = { 105 /* 106 * Minimum required 107 */ 108 [SYS_exit] = PLEDGE_ALWAYS, 109 [SYS_kbind] = PLEDGE_ALWAYS, 110 [SYS_msyscall] = PLEDGE_ALWAYS, 111 [SYS___get_tcb] = PLEDGE_ALWAYS, 112 [SYS___set_tcb] = PLEDGE_ALWAYS, 113 [SYS_pledge] = PLEDGE_ALWAYS, 114 [SYS_sendsyslog] = PLEDGE_ALWAYS, /* stack protector reporting */ 115 [SYS_thrkill] = PLEDGE_ALWAYS, /* raise, abort, stack pro */ 116 [SYS_utrace] = PLEDGE_ALWAYS, /* ltrace(1) from ld.so */ 117 118 /* "getting" information about self is considered safe */ 119 [SYS_getuid] = PLEDGE_STDIO, 120 [SYS_geteuid] = PLEDGE_STDIO, 121 [SYS_getresuid] = PLEDGE_STDIO, 122 [SYS_getgid] = PLEDGE_STDIO, 123 [SYS_getegid] = PLEDGE_STDIO, 124 [SYS_getresgid] = PLEDGE_STDIO, 125 [SYS_getgroups] = PLEDGE_STDIO, 126 [SYS_getlogin_r] = PLEDGE_STDIO, 127 [SYS_getpgrp] = PLEDGE_STDIO, 128 [SYS_getpgid] = PLEDGE_STDIO, 129 [SYS_getppid] = PLEDGE_STDIO, 130 [SYS_getsid] = PLEDGE_STDIO, 131 [SYS_getthrid] = PLEDGE_STDIO, 132 [SYS_getrlimit] = PLEDGE_STDIO, 133 [SYS_getrtable] = PLEDGE_STDIO, 134 [SYS_gettimeofday] = PLEDGE_STDIO, 135 [SYS_getdtablecount] = PLEDGE_STDIO, 136 [SYS_getrusage] = PLEDGE_STDIO, 137 [SYS_issetugid] = PLEDGE_STDIO, 138 [SYS_clock_getres] = PLEDGE_STDIO, 139 [SYS_clock_gettime] = PLEDGE_STDIO, 140 [SYS_getpid] = PLEDGE_STDIO, 141 142 /* 143 * Almost exclusively read-only, Very narrow subset. 144 * Use of "route", "inet", "dns", "ps", or "vminfo" 145 * expands access. 146 */ 147 [SYS_sysctl] = PLEDGE_STDIO, 148 149 /* Support for malloc(3) family of operations */ 150 [SYS_getentropy] = PLEDGE_STDIO, 151 [SYS_madvise] = PLEDGE_STDIO, 152 [SYS_minherit] = PLEDGE_STDIO, 153 [SYS_mmap] = PLEDGE_STDIO, 154 [SYS_mprotect] = PLEDGE_STDIO, 155 [SYS_mquery] = PLEDGE_STDIO, 156 [SYS_munmap] = PLEDGE_STDIO, 157 [SYS_msync] = PLEDGE_STDIO, 158 [SYS_break] = PLEDGE_STDIO, 159 160 [SYS_umask] = PLEDGE_STDIO, 161 162 /* read/write operations */ 163 [SYS_read] = PLEDGE_STDIO, 164 [SYS_readv] = PLEDGE_STDIO, 165 [SYS_pread] = PLEDGE_STDIO, 166 [SYS_preadv] = PLEDGE_STDIO, 167 [SYS_write] = PLEDGE_STDIO, 168 [SYS_writev] = PLEDGE_STDIO, 169 [SYS_pwrite] = PLEDGE_STDIO, 170 [SYS_pwritev] = PLEDGE_STDIO, 171 [SYS_recvmsg] = PLEDGE_STDIO, 172 [SYS_recvfrom] = PLEDGE_STDIO | PLEDGE_YPACTIVE, 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 | PLEDGE_YPACTIVE, 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, 200 201 /* Common signal operations */ 202 [SYS_nanosleep] = PLEDGE_STDIO, 203 [SYS_sigaltstack] = PLEDGE_STDIO, 204 [SYS_sigprocmask] = PLEDGE_STDIO, 205 [SYS_sigsuspend] = PLEDGE_STDIO, 206 [SYS_sigaction] = PLEDGE_STDIO, 207 [SYS_sigreturn] = PLEDGE_STDIO, 208 [SYS_sigpending] = PLEDGE_STDIO, 209 [SYS_getitimer] = PLEDGE_STDIO, 210 [SYS_setitimer] = PLEDGE_STDIO, 211 212 /* 213 * To support event driven programming. 214 */ 215 [SYS_poll] = PLEDGE_STDIO, 216 [SYS_ppoll] = PLEDGE_STDIO, 217 [SYS_kevent] = PLEDGE_STDIO, 218 [SYS_kqueue] = PLEDGE_STDIO, 219 [SYS_select] = PLEDGE_STDIO, 220 [SYS_pselect] = PLEDGE_STDIO, 221 222 [SYS_fstat] = PLEDGE_STDIO, 223 [SYS_fsync] = PLEDGE_STDIO, 224 225 [SYS_setsockopt] = PLEDGE_STDIO, /* narrow whitelist */ 226 [SYS_getsockopt] = PLEDGE_STDIO, /* narrow whitelist */ 227 228 /* F_SETOWN requires PLEDGE_PROC */ 229 [SYS_fcntl] = PLEDGE_STDIO, 230 231 [SYS_close] = PLEDGE_STDIO, 232 [SYS_dup] = PLEDGE_STDIO, 233 [SYS_dup2] = PLEDGE_STDIO, 234 [SYS_dup3] = PLEDGE_STDIO, 235 [SYS_closefrom] = PLEDGE_STDIO, 236 [SYS_shutdown] = PLEDGE_STDIO, 237 [SYS_fchdir] = PLEDGE_STDIO, /* XXX consider tightening */ 238 239 [SYS_pipe] = PLEDGE_STDIO, 240 [SYS_pipe2] = PLEDGE_STDIO, 241 [SYS_socketpair] = PLEDGE_STDIO, 242 243 [SYS_wait4] = PLEDGE_STDIO, 244 245 /* 246 * Can kill self with "stdio". Killing another pid 247 * requires "proc" 248 */ 249 [SYS_kill] = PLEDGE_STDIO, 250 251 /* 252 * FIONREAD/FIONBIO for "stdio" 253 * Other ioctl are selectively allowed based upon other pledges. 254 */ 255 [SYS_ioctl] = PLEDGE_STDIO, 256 257 /* 258 * Path access/creation calls encounter many extensive 259 * checks done during pledge_namei() 260 */ 261 [SYS_open] = PLEDGE_STDIO, 262 [SYS_stat] = PLEDGE_STDIO, 263 [SYS_access] = PLEDGE_STDIO, 264 [SYS_readlink] = PLEDGE_STDIO, 265 [SYS___realpath] = PLEDGE_STDIO, 266 267 [SYS_adjtime] = PLEDGE_STDIO, /* setting requires "settime" */ 268 [SYS_adjfreq] = PLEDGE_SETTIME, 269 [SYS_settimeofday] = PLEDGE_SETTIME, 270 271 /* 272 * Needed by threaded programs 273 * XXX should we have a new "threads"? 274 */ 275 [SYS___tfork] = PLEDGE_STDIO, 276 [SYS_sched_yield] = PLEDGE_STDIO, 277 [SYS_futex] = PLEDGE_STDIO, 278 [SYS___thrsleep] = PLEDGE_STDIO, 279 [SYS___thrwakeup] = PLEDGE_STDIO, 280 [SYS___threxit] = PLEDGE_STDIO, 281 [SYS___thrsigdivert] = PLEDGE_STDIO, 282 283 [SYS_fork] = PLEDGE_PROC, 284 [SYS_vfork] = PLEDGE_PROC, 285 [SYS_setpgid] = PLEDGE_PROC, 286 [SYS_setsid] = PLEDGE_PROC, 287 288 [SYS_setrlimit] = PLEDGE_PROC | PLEDGE_ID, 289 [SYS_getpriority] = PLEDGE_PROC | PLEDGE_ID, 290 291 [SYS_setpriority] = PLEDGE_PROC | PLEDGE_ID, 292 293 [SYS_setuid] = PLEDGE_ID, 294 [SYS_seteuid] = PLEDGE_ID, 295 [SYS_setreuid] = PLEDGE_ID, 296 [SYS_setresuid] = PLEDGE_ID, 297 [SYS_setgid] = PLEDGE_ID, 298 [SYS_setegid] = PLEDGE_ID, 299 [SYS_setregid] = PLEDGE_ID, 300 [SYS_setresgid] = PLEDGE_ID, 301 [SYS_setgroups] = PLEDGE_ID, 302 [SYS_setlogin] = PLEDGE_ID, 303 [SYS_setrtable] = PLEDGE_ID, 304 305 [SYS_unveil] = PLEDGE_UNVEIL, 306 307 [SYS_execve] = PLEDGE_EXEC, 308 309 [SYS_chdir] = PLEDGE_RPATH, 310 [SYS_openat] = PLEDGE_RPATH | PLEDGE_WPATH, 311 [SYS_fstatat] = PLEDGE_RPATH | PLEDGE_WPATH, 312 [SYS_faccessat] = PLEDGE_RPATH | PLEDGE_WPATH, 313 [SYS_readlinkat] = PLEDGE_RPATH | PLEDGE_WPATH, 314 [SYS_lstat] = PLEDGE_RPATH | PLEDGE_WPATH | PLEDGE_TMPPATH, 315 [SYS_truncate] = PLEDGE_WPATH, 316 [SYS_rename] = PLEDGE_RPATH | PLEDGE_CPATH, 317 [SYS_rmdir] = PLEDGE_CPATH, 318 [SYS_renameat] = PLEDGE_CPATH, 319 [SYS_link] = PLEDGE_CPATH, 320 [SYS_linkat] = PLEDGE_CPATH, 321 [SYS_symlink] = PLEDGE_CPATH, 322 [SYS_symlinkat] = PLEDGE_CPATH, 323 [SYS_unlink] = PLEDGE_CPATH | PLEDGE_TMPPATH, 324 [SYS_unlinkat] = PLEDGE_CPATH, 325 [SYS_mkdir] = PLEDGE_CPATH, 326 [SYS_mkdirat] = PLEDGE_CPATH, 327 328 [SYS_mkfifo] = PLEDGE_DPATH, 329 [SYS_mkfifoat] = PLEDGE_DPATH, 330 [SYS_mknod] = PLEDGE_DPATH, 331 [SYS_mknodat] = PLEDGE_DPATH, 332 333 [SYS_revoke] = PLEDGE_TTY, /* also requires PLEDGE_RPATH */ 334 335 /* 336 * Classify as RPATH|WPATH, because of path information leakage. 337 * WPATH due to unknown use of mk*temp(3) on non-/tmp paths.. 338 */ 339 [SYS___getcwd] = PLEDGE_RPATH | PLEDGE_WPATH, 340 341 /* Classify as RPATH, because these leak path information */ 342 [SYS_getdents] = PLEDGE_RPATH, 343 [SYS_getfsstat] = PLEDGE_RPATH, 344 [SYS_statfs] = PLEDGE_RPATH, 345 [SYS_fstatfs] = PLEDGE_RPATH, 346 [SYS_pathconf] = PLEDGE_RPATH, 347 348 [SYS_utimes] = PLEDGE_FATTR, 349 [SYS_futimes] = PLEDGE_FATTR, 350 [SYS_utimensat] = PLEDGE_FATTR, 351 [SYS_futimens] = PLEDGE_FATTR, 352 [SYS_chmod] = PLEDGE_FATTR, 353 [SYS_fchmod] = PLEDGE_FATTR, 354 [SYS_fchmodat] = PLEDGE_FATTR, 355 [SYS_chflags] = PLEDGE_FATTR, 356 [SYS_chflagsat] = PLEDGE_FATTR, 357 [SYS_fchflags] = PLEDGE_FATTR, 358 359 [SYS_chown] = PLEDGE_CHOWN, 360 [SYS_fchownat] = PLEDGE_CHOWN, 361 [SYS_lchown] = PLEDGE_CHOWN, 362 [SYS_fchown] = PLEDGE_CHOWN, 363 364 [SYS_socket] = PLEDGE_INET | PLEDGE_UNIX | PLEDGE_DNS | PLEDGE_YPACTIVE, 365 [SYS_connect] = PLEDGE_INET | PLEDGE_UNIX | PLEDGE_DNS | PLEDGE_YPACTIVE, 366 [SYS_bind] = PLEDGE_INET | PLEDGE_UNIX | PLEDGE_DNS | PLEDGE_YPACTIVE, 367 [SYS_getsockname] = PLEDGE_INET | PLEDGE_UNIX | PLEDGE_DNS | PLEDGE_YPACTIVE, 368 369 [SYS_listen] = PLEDGE_INET | PLEDGE_UNIX, 370 [SYS_accept4] = PLEDGE_INET | PLEDGE_UNIX, 371 [SYS_accept] = PLEDGE_INET | PLEDGE_UNIX, 372 [SYS_getpeername] = PLEDGE_INET | PLEDGE_UNIX, 373 374 [SYS_flock] = PLEDGE_FLOCK | PLEDGE_YPACTIVE, 375 376 [SYS_swapctl] = PLEDGE_VMINFO, /* XXX should limit to "get" operations */ 377 }; 378 379 static const struct { 380 char *name; 381 uint64_t flags; 382 } pledgereq[] = { 383 { "audio", PLEDGE_AUDIO }, 384 { "bpf", PLEDGE_BPF }, 385 { "chown", PLEDGE_CHOWN | PLEDGE_CHOWNUID }, 386 { "cpath", PLEDGE_CPATH }, 387 { "disklabel", PLEDGE_DISKLABEL }, 388 { "dns", PLEDGE_DNS }, 389 { "dpath", PLEDGE_DPATH }, 390 { "drm", PLEDGE_DRM }, 391 { "error", PLEDGE_ERROR }, 392 { "exec", PLEDGE_EXEC }, 393 { "fattr", PLEDGE_FATTR | PLEDGE_CHOWN }, 394 { "flock", PLEDGE_FLOCK }, 395 { "getpw", PLEDGE_GETPW }, 396 { "id", PLEDGE_ID }, 397 { "inet", PLEDGE_INET }, 398 { "mcast", PLEDGE_MCAST }, 399 { "pf", PLEDGE_PF }, 400 { "proc", PLEDGE_PROC }, 401 { "prot_exec", PLEDGE_PROTEXEC }, 402 { "ps", PLEDGE_PS }, 403 { "recvfd", PLEDGE_RECVFD }, 404 { "route", PLEDGE_ROUTE }, 405 { "rpath", PLEDGE_RPATH }, 406 { "sendfd", PLEDGE_SENDFD }, 407 { "settime", PLEDGE_SETTIME }, 408 { "stdio", PLEDGE_STDIO }, 409 { "tape", PLEDGE_TAPE }, 410 { "tmppath", PLEDGE_TMPPATH }, 411 { "tty", PLEDGE_TTY }, 412 { "unix", PLEDGE_UNIX }, 413 { "unveil", PLEDGE_UNVEIL }, 414 { "video", PLEDGE_VIDEO }, 415 { "vminfo", PLEDGE_VMINFO }, 416 { "vmm", PLEDGE_VMM }, 417 { "wpath", PLEDGE_WPATH }, 418 { "wroute", PLEDGE_WROUTE }, 419 }; 420 421 int 422 parsepledges(struct proc *p, const char *kname, const char *promises, u_int64_t *fp) 423 { 424 size_t rbuflen; 425 char *rbuf, *rp, *pn; 426 u_int64_t flags = 0, f; 427 int error; 428 429 rbuf = malloc(MAXPATHLEN, M_TEMP, M_WAITOK); 430 error = copyinstr(promises, rbuf, MAXPATHLEN, 431 &rbuflen); 432 if (error) { 433 free(rbuf, M_TEMP, MAXPATHLEN); 434 return (error); 435 } 436 #ifdef KTRACE 437 if (KTRPOINT(p, KTR_STRUCT)) 438 ktrstruct(p, kname, rbuf, rbuflen-1); 439 #endif 440 441 for (rp = rbuf; rp && *rp; rp = pn) { 442 pn = strchr(rp, ' '); /* find terminator */ 443 if (pn) { 444 while (*pn == ' ') 445 *pn++ = '\0'; 446 } 447 if ((f = pledgereq_flags(rp)) == 0) { 448 free(rbuf, M_TEMP, MAXPATHLEN); 449 return (EINVAL); 450 } 451 flags |= f; 452 } 453 free(rbuf, M_TEMP, MAXPATHLEN); 454 *fp = flags; 455 return 0; 456 } 457 458 int 459 sys_pledge(struct proc *p, void *v, register_t *retval) 460 { 461 struct sys_pledge_args /* { 462 syscallarg(const char *)promises; 463 syscallarg(const char *)execpromises; 464 } */ *uap = v; 465 struct process *pr = p->p_p; 466 uint64_t promises, execpromises; 467 int error; 468 469 if (SCARG(uap, promises)) { 470 error = parsepledges(p, "pledgereq", 471 SCARG(uap, promises), &promises); 472 if (error) 473 return (error); 474 475 /* In "error" mode, ignore promise increase requests, 476 * but accept promise decrease requests */ 477 if (ISSET(pr->ps_flags, PS_PLEDGE) && 478 (pr->ps_pledge & PLEDGE_ERROR)) 479 promises &= (pr->ps_pledge & PLEDGE_USERSET); 480 481 /* Only permit reductions */ 482 if (ISSET(pr->ps_flags, PS_PLEDGE) && 483 (((promises | pr->ps_pledge) != pr->ps_pledge))) 484 return (EPERM); 485 } 486 if (SCARG(uap, execpromises)) { 487 error = parsepledges(p, "pledgeexecreq", 488 SCARG(uap, execpromises), &execpromises); 489 if (error) 490 return (error); 491 492 /* Only permit reductions */ 493 if (ISSET(pr->ps_flags, PS_EXECPLEDGE) && 494 (((execpromises | pr->ps_execpledge) != pr->ps_execpledge))) 495 return (EPERM); 496 } 497 498 if (SCARG(uap, promises)) { 499 pr->ps_pledge = promises; 500 atomic_setbits_int(&pr->ps_flags, PS_PLEDGE); 501 /* 502 * Kill off unveil and drop unveil vnode refs if we no 503 * longer are holding any path-accessing pledge 504 */ 505 if ((pr->ps_pledge & (PLEDGE_RPATH | PLEDGE_WPATH | 506 PLEDGE_CPATH | PLEDGE_DPATH | PLEDGE_TMPPATH | PLEDGE_EXEC | 507 PLEDGE_UNIX | PLEDGE_UNVEIL)) == 0) 508 unveil_destroy(pr); 509 } 510 if (SCARG(uap, execpromises)) { 511 pr->ps_execpledge = execpromises; 512 atomic_setbits_int(&pr->ps_flags, PS_EXECPLEDGE); 513 } 514 return (0); 515 } 516 517 int 518 pledge_syscall(struct proc *p, int code, uint64_t *tval) 519 { 520 p->p_pledge_syscall = code; 521 *tval = 0; 522 523 if (code < 0 || code > SYS_MAXSYSCALL - 1) 524 return (EINVAL); 525 526 if (pledge_syscalls[code] == PLEDGE_ALWAYS) 527 return (0); 528 529 if (p->p_p->ps_pledge & pledge_syscalls[code]) 530 return (0); 531 532 *tval = pledge_syscalls[code]; 533 return (EPERM); 534 } 535 536 int 537 pledge_fail(struct proc *p, int error, uint64_t code) 538 { 539 const char *codes = ""; 540 int i; 541 542 /* Print first matching pledge */ 543 for (i = 0; code && pledgenames[i].bits != 0; i++) 544 if (pledgenames[i].bits & code) { 545 codes = pledgenames[i].name; 546 break; 547 } 548 #ifdef KTRACE 549 if (KTRPOINT(p, KTR_PLEDGE)) 550 ktrpledge(p, error, code, p->p_pledge_syscall); 551 #endif 552 if (p->p_p->ps_pledge & PLEDGE_ERROR) 553 return (ENOSYS); 554 555 KERNEL_LOCK(); 556 log(LOG_ERR, "%s[%d]: pledge \"%s\", syscall %d\n", 557 p->p_p->ps_comm, p->p_p->ps_pid, codes, p->p_pledge_syscall); 558 p->p_p->ps_acflag |= APLEDGE; 559 560 /* Stop threads immediately, because this process is suspect */ 561 if (P_HASSIBLING(p)) 562 single_thread_set(p, SINGLE_SUSPEND, 1); 563 564 /* Send uncatchable SIGABRT for coredump */ 565 sigabort(p); 566 567 p->p_p->ps_pledge = 0; /* Disable all PLEDGE_ flags */ 568 KERNEL_UNLOCK(); 569 return (error); 570 } 571 572 /* 573 * Need to make it more obvious that one cannot get through here 574 * without the right flags set 575 */ 576 int 577 pledge_namei(struct proc *p, struct nameidata *ni, char *origpath) 578 { 579 char path[PATH_MAX]; 580 uint64_t pledge; 581 int error; 582 583 if ((p->p_p->ps_flags & PS_PLEDGE) == 0 || 584 (p->p_p->ps_flags & PS_COREDUMP)) 585 return (0); 586 pledge = p->p_p->ps_pledge; 587 588 if (ni->ni_pledge == 0) 589 panic("pledge_namei: ni_pledge"); 590 591 /* 592 * We set the BYPASSUNVEIL flag to skip unveil checks 593 * as necessary 594 */ 595 596 /* Doing a permitted execve() */ 597 if ((ni->ni_pledge & PLEDGE_EXEC) && 598 (pledge & PLEDGE_EXEC)) 599 return (0); 600 601 error = canonpath(origpath, path, sizeof(path)); 602 if (error) 603 return (error); 604 605 /* Detect what looks like a mkstemp(3) family operation */ 606 if ((pledge & PLEDGE_TMPPATH) && 607 (p->p_pledge_syscall == SYS_open) && 608 (ni->ni_pledge & PLEDGE_CPATH) && 609 strncmp(path, "/tmp/", sizeof("/tmp/") - 1) == 0) { 610 ni->ni_cnd.cn_flags |= BYPASSUNVEIL; 611 return (0); 612 } 613 614 /* Allow unlinking of a mkstemp(3) file... 615 * Good opportunity for strict checks here. 616 */ 617 if ((pledge & PLEDGE_TMPPATH) && 618 (p->p_pledge_syscall == SYS_unlink) && 619 strncmp(path, "/tmp/", sizeof("/tmp/") - 1) == 0) { 620 ni->ni_cnd.cn_flags |= BYPASSUNVEIL; 621 return (0); 622 } 623 624 /* Whitelisted paths */ 625 switch (p->p_pledge_syscall) { 626 case SYS_access: 627 /* tzset() needs this. */ 628 if (ni->ni_pledge == PLEDGE_RPATH && 629 strcmp(path, "/etc/localtime") == 0) { 630 ni->ni_cnd.cn_flags |= BYPASSUNVEIL; 631 return (0); 632 } 633 634 /* when avoiding YP mode, getpw* functions touch this */ 635 if (ni->ni_pledge == PLEDGE_RPATH && 636 strcmp(path, "/var/run/ypbind.lock") == 0) { 637 if (pledge & PLEDGE_GETPW) { 638 ni->ni_cnd.cn_flags |= BYPASSUNVEIL; 639 return (0); 640 } else 641 return (pledge_fail(p, error, PLEDGE_GETPW)); 642 } 643 break; 644 case SYS_open: 645 /* daemon(3) or other such functions */ 646 if ((ni->ni_pledge & ~(PLEDGE_RPATH | PLEDGE_WPATH)) == 0 && 647 strcmp(path, "/dev/null") == 0) { 648 ni->ni_cnd.cn_flags |= BYPASSUNVEIL; 649 return (0); 650 } 651 652 /* readpassphrase(3), getpass(3) */ 653 if ((pledge & PLEDGE_TTY) && 654 (ni->ni_pledge & ~(PLEDGE_RPATH | PLEDGE_WPATH)) == 0 && 655 strcmp(path, "/dev/tty") == 0) { 656 ni->ni_cnd.cn_flags |= BYPASSUNVEIL; 657 return (0); 658 } 659 660 /* getpw* and friends need a few files */ 661 if ((ni->ni_pledge == PLEDGE_RPATH) && 662 (pledge & PLEDGE_GETPW)) { 663 if (strcmp(path, "/etc/spwd.db") == 0) 664 return (EPERM); /* don't call pledge_fail */ 665 if (strcmp(path, "/etc/pwd.db") == 0) { 666 ni->ni_cnd.cn_flags |= BYPASSUNVEIL; 667 return (0); 668 } 669 if (strcmp(path, "/etc/group") == 0) { 670 ni->ni_cnd.cn_flags |= BYPASSUNVEIL; 671 return (0); 672 } 673 if (strcmp(path, "/etc/netid") == 0) { 674 ni->ni_cnd.cn_flags |= BYPASSUNVEIL; 675 return (0); 676 } 677 } 678 679 /* DNS needs /etc/{resolv.conf,hosts,services,protocols}. */ 680 if ((ni->ni_pledge == PLEDGE_RPATH) && 681 (pledge & PLEDGE_DNS)) { 682 if (strcmp(path, "/etc/resolv.conf") == 0) { 683 ni->ni_cnd.cn_flags |= BYPASSUNVEIL; 684 return (0); 685 } 686 if (strcmp(path, "/etc/hosts") == 0) { 687 ni->ni_cnd.cn_flags |= BYPASSUNVEIL; 688 return (0); 689 } 690 if (strcmp(path, "/etc/services") == 0) { 691 ni->ni_cnd.cn_flags |= BYPASSUNVEIL; 692 return (0); 693 } 694 if (strcmp(path, "/etc/protocols") == 0) { 695 ni->ni_cnd.cn_flags |= BYPASSUNVEIL; 696 return (0); 697 } 698 } 699 700 if ((ni->ni_pledge == PLEDGE_RPATH) && 701 (pledge & PLEDGE_GETPW)) { 702 if (strcmp(path, "/var/run/ypbind.lock") == 0) { 703 /* 704 * XXX 705 * The current hack for YP support in "getpw" 706 * is to enable some "inet" features until 707 * next pledge call. Setting a bit in ps_pledge 708 * is not safe with respect to multiple threads, 709 * a very different approach is needed. 710 */ 711 p->p_p->ps_pledge |= PLEDGE_YPACTIVE; 712 ni->ni_cnd.cn_flags |= BYPASSUNVEIL; 713 return (0); 714 } 715 if (strncmp(path, "/var/yp/binding/", 716 sizeof("/var/yp/binding/") - 1) == 0) { 717 ni->ni_cnd.cn_flags |= BYPASSUNVEIL; 718 return (0); 719 } 720 } 721 722 /* tzset() needs these. */ 723 if ((ni->ni_pledge == PLEDGE_RPATH) && 724 strncmp(path, "/usr/share/zoneinfo/", 725 sizeof("/usr/share/zoneinfo/") - 1) == 0) { 726 ni->ni_cnd.cn_flags |= BYPASSUNVEIL; 727 return (0); 728 } 729 if ((ni->ni_pledge == PLEDGE_RPATH) && 730 strcmp(path, "/etc/localtime") == 0) { 731 ni->ni_cnd.cn_flags |= BYPASSUNVEIL; 732 return (0); 733 } 734 735 break; 736 case SYS_stat: 737 /* DNS needs /etc/{resolv.conf,hosts}. */ 738 if ((ni->ni_pledge == PLEDGE_RPATH) && 739 (pledge & PLEDGE_DNS)) { 740 if (strcmp(path, "/etc/resolv.conf") == 0) { 741 ni->ni_cnd.cn_flags |= BYPASSUNVEIL; 742 return (0); 743 } 744 if (strcmp(path, "/etc/hosts") == 0) { 745 ni->ni_cnd.cn_flags |= BYPASSUNVEIL; 746 return (0); 747 } 748 } 749 break; 750 } 751 752 /* 753 * Ensure each flag of ni_pledge has counterpart allowing it in 754 * ps_pledge. 755 */ 756 if (ni->ni_pledge & ~pledge) 757 return (pledge_fail(p, EPERM, (ni->ni_pledge & ~pledge))); 758 759 /* continue, and check unveil if present */ 760 return (0); 761 } 762 763 /* 764 * Only allow reception of safe file descriptors. 765 */ 766 int 767 pledge_recvfd(struct proc *p, struct file *fp) 768 { 769 struct vnode *vp; 770 771 if ((p->p_p->ps_flags & PS_PLEDGE) == 0) 772 return (0); 773 if ((p->p_p->ps_pledge & PLEDGE_RECVFD) == 0) 774 return pledge_fail(p, EPERM, PLEDGE_RECVFD); 775 776 switch (fp->f_type) { 777 case DTYPE_SOCKET: 778 case DTYPE_PIPE: 779 case DTYPE_DMABUF: 780 case DTYPE_SYNC: 781 return (0); 782 case DTYPE_VNODE: 783 vp = fp->f_data; 784 785 if (vp->v_type != VDIR) 786 return (0); 787 } 788 return pledge_fail(p, EINVAL, PLEDGE_RECVFD); 789 } 790 791 /* 792 * Only allow sending of safe file descriptors. 793 */ 794 int 795 pledge_sendfd(struct proc *p, struct file *fp) 796 { 797 struct vnode *vp; 798 799 if ((p->p_p->ps_flags & PS_PLEDGE) == 0) 800 return (0); 801 if ((p->p_p->ps_pledge & PLEDGE_SENDFD) == 0) 802 return pledge_fail(p, EPERM, PLEDGE_SENDFD); 803 804 switch (fp->f_type) { 805 case DTYPE_SOCKET: 806 case DTYPE_PIPE: 807 case DTYPE_DMABUF: 808 case DTYPE_SYNC: 809 return (0); 810 case DTYPE_VNODE: 811 vp = fp->f_data; 812 813 if (vp->v_type != VDIR) 814 return (0); 815 break; 816 } 817 return pledge_fail(p, EINVAL, PLEDGE_SENDFD); 818 } 819 820 int 821 pledge_sysctl(struct proc *p, int miblen, int *mib, void *new) 822 { 823 char buf[80]; 824 uint64_t pledge; 825 int i; 826 827 if ((p->p_p->ps_flags & PS_PLEDGE) == 0) 828 return (0); 829 pledge = p->p_p->ps_pledge; 830 831 if (new) 832 return pledge_fail(p, EFAULT, 0); 833 834 /* routing table observation */ 835 if ((pledge & PLEDGE_ROUTE)) { 836 if ((miblen == 6 || miblen == 7) && 837 mib[0] == CTL_NET && mib[1] == PF_ROUTE && 838 mib[2] == 0 && 839 mib[4] == NET_RT_DUMP) 840 return (0); 841 842 if (miblen == 6 && 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_TABLE || mib[4] == NET_RT_SOURCE)) 847 return (0); 848 849 if (miblen == 7 && /* exposes MACs */ 850 mib[0] == CTL_NET && mib[1] == PF_ROUTE && 851 mib[2] == 0 && 852 (mib[3] == 0 || mib[3] == AF_INET6 || mib[3] == AF_INET) && 853 mib[4] == NET_RT_FLAGS && mib[5] == RTF_LLINFO) 854 return (0); 855 } 856 857 if ((pledge & PLEDGE_WROUTE)) { 858 if (miblen == 4 && 859 mib[0] == CTL_NET && mib[1] == PF_INET6 && 860 mib[2] == IPPROTO_IPV6 && mib[3] == IPV6CTL_SOIIKEY) 861 return (0); 862 } 863 864 if (pledge & (PLEDGE_PS | PLEDGE_VMINFO)) { 865 if (miblen == 2 && /* kern.fscale */ 866 mib[0] == CTL_KERN && mib[1] == KERN_FSCALE) 867 return (0); 868 if (miblen == 2 && /* kern.boottime */ 869 mib[0] == CTL_KERN && mib[1] == KERN_BOOTTIME) 870 return (0); 871 if (miblen == 2 && /* kern.consdev */ 872 mib[0] == CTL_KERN && mib[1] == KERN_CONSDEV) 873 return (0); 874 if (miblen == 2 && /* kern.cptime */ 875 mib[0] == CTL_KERN && mib[1] == KERN_CPTIME) 876 return (0); 877 if (miblen == 3 && /* kern.cptime2 */ 878 mib[0] == CTL_KERN && mib[1] == KERN_CPTIME2) 879 return (0); 880 if (miblen == 3 && /* kern.cpustats */ 881 mib[0] == CTL_KERN && mib[1] == KERN_CPUSTATS) 882 return (0); 883 } 884 885 if ((pledge & PLEDGE_PS)) { 886 if (miblen == 4 && /* kern.procargs.* */ 887 mib[0] == CTL_KERN && mib[1] == KERN_PROC_ARGS && 888 (mib[3] == KERN_PROC_ARGV || mib[3] == KERN_PROC_ENV)) 889 return (0); 890 if (miblen == 6 && /* kern.proc.* */ 891 mib[0] == CTL_KERN && mib[1] == KERN_PROC) 892 return (0); 893 if (miblen == 3 && /* kern.proc_cwd.* */ 894 mib[0] == CTL_KERN && mib[1] == KERN_PROC_CWD) 895 return (0); 896 if (miblen == 2 && /* kern.ccpu */ 897 mib[0] == CTL_KERN && mib[1] == KERN_CCPU) 898 return (0); 899 if (miblen == 2 && /* vm.maxslp */ 900 mib[0] == CTL_VM && mib[1] == VM_MAXSLP) 901 return (0); 902 } 903 904 if ((pledge & PLEDGE_VMINFO)) { 905 if (miblen == 2 && /* vm.uvmexp */ 906 mib[0] == CTL_VM && mib[1] == VM_UVMEXP) 907 return (0); 908 if (miblen == 3 && /* vfs.generic.bcachestat */ 909 mib[0] == CTL_VFS && mib[1] == VFS_GENERIC && 910 mib[2] == VFS_BCACHESTAT) 911 return (0); 912 } 913 914 if ((pledge & (PLEDGE_INET | PLEDGE_UNIX))) { 915 if (miblen == 2 && /* kern.somaxconn */ 916 mib[0] == CTL_KERN && mib[1] == KERN_SOMAXCONN) 917 return (0); 918 } 919 920 if ((pledge & (PLEDGE_ROUTE | PLEDGE_INET | PLEDGE_DNS))) { 921 if (miblen == 6 && /* getifaddrs() */ 922 mib[0] == CTL_NET && mib[1] == PF_ROUTE && 923 mib[2] == 0 && 924 (mib[3] == 0 || mib[3] == AF_INET6 || mib[3] == AF_INET) && 925 mib[4] == NET_RT_IFLIST) 926 return (0); 927 } 928 929 if ((pledge & PLEDGE_DISKLABEL)) { 930 if (miblen == 2 && /* kern.rawpartition */ 931 mib[0] == CTL_KERN && 932 mib[1] == KERN_RAWPARTITION) 933 return (0); 934 if (miblen == 2 && /* kern.maxpartitions */ 935 mib[0] == CTL_KERN && 936 mib[1] == KERN_MAXPARTITIONS) 937 return (0); 938 #ifdef CPU_CHR2BLK 939 if (miblen == 3 && /* machdep.chr2blk */ 940 mib[0] == CTL_MACHDEP && 941 mib[1] == CPU_CHR2BLK) 942 return (0); 943 #endif /* CPU_CHR2BLK */ 944 } 945 946 if (miblen >= 3 && /* ntpd(8) to read sensors */ 947 mib[0] == CTL_HW && mib[1] == HW_SENSORS) 948 return (0); 949 950 if (miblen == 6 && /* if_nameindex() */ 951 mib[0] == CTL_NET && mib[1] == PF_ROUTE && 952 mib[2] == 0 && mib[3] == 0 && mib[4] == NET_RT_IFNAMES) 953 return (0); 954 955 if (miblen == 2) { 956 switch (mib[0]) { 957 case CTL_KERN: 958 switch (mib[1]) { 959 case KERN_DOMAINNAME: /* getdomainname() */ 960 case KERN_HOSTNAME: /* gethostname() */ 961 case KERN_OSTYPE: /* uname() */ 962 case KERN_OSRELEASE: /* uname() */ 963 case KERN_OSVERSION: /* uname() */ 964 case KERN_VERSION: /* uname() */ 965 case KERN_CLOCKRATE: /* kern.clockrate */ 966 case KERN_ARGMAX: /* kern.argmax */ 967 case KERN_NGROUPS: /* kern.ngroups */ 968 case KERN_SYSVSHM: /* kern.sysvshm */ 969 case KERN_POSIX1: /* kern.posix1version */ 970 return (0); 971 } 972 break; 973 case CTL_HW: 974 switch (mib[1]) { 975 case HW_MACHINE: /* uname() */ 976 case HW_PAGESIZE: /* getpagesize() */ 977 case HW_PHYSMEM64: /* hw.physmem */ 978 case HW_NCPU: /* hw.ncpu */ 979 case HW_NCPUONLINE: /* hw.ncpuonline */ 980 return (0); 981 } 982 break; 983 case CTL_VM: 984 switch (mib[1]) { 985 case VM_PSSTRINGS: /* setproctitle() */ 986 case VM_LOADAVG: /* vm.loadavg / getloadavg(3) */ 987 case VM_MALLOC_CONF: /* vm.malloc_conf */ 988 return (0); 989 } 990 break; 991 default: 992 break; 993 } 994 } 995 996 #ifdef CPU_SSE 997 if (miblen == 2 && /* i386 libm tests for SSE */ 998 mib[0] == CTL_MACHDEP && mib[1] == CPU_SSE) 999 return (0); 1000 #endif /* CPU_SSE */ 1001 1002 #ifdef CPU_ID_AA64ISAR0 1003 if (miblen == 2 && /* arm64 libcrypto inspects CPU features */ 1004 mib[0] == CTL_MACHDEP && mib[1] == CPU_ID_AA64ISAR0) 1005 return (0); 1006 #endif /* CPU_ID_AA64ISAR0 */ 1007 1008 snprintf(buf, sizeof(buf), "%s(%d): pledge sysctl %d:", 1009 p->p_p->ps_comm, p->p_p->ps_pid, miblen); 1010 for (i = 0; i < miblen; i++) { 1011 char *p = buf + strlen(buf); 1012 snprintf(p, sizeof(buf) - (p - buf), " %d", mib[i]); 1013 } 1014 log(LOG_ERR, "%s\n", buf); 1015 1016 return pledge_fail(p, EINVAL, 0); 1017 } 1018 1019 int 1020 pledge_chown(struct proc *p, uid_t uid, gid_t gid) 1021 { 1022 if ((p->p_p->ps_flags & PS_PLEDGE) == 0) 1023 return (0); 1024 1025 if (p->p_p->ps_pledge & PLEDGE_CHOWNUID) 1026 return (0); 1027 1028 if (uid != -1 && uid != p->p_ucred->cr_uid) 1029 return (EPERM); 1030 if (gid != -1 && !groupmember(gid, p->p_ucred)) 1031 return (EPERM); 1032 return (0); 1033 } 1034 1035 int 1036 pledge_adjtime(struct proc *p, const void *v) 1037 { 1038 const struct timeval *delta = v; 1039 1040 if ((p->p_p->ps_flags & PS_PLEDGE) == 0) 1041 return (0); 1042 1043 if ((p->p_p->ps_pledge & PLEDGE_SETTIME)) 1044 return (0); 1045 if (delta) 1046 return (EPERM); 1047 return (0); 1048 } 1049 1050 int 1051 pledge_sendit(struct proc *p, const void *to) 1052 { 1053 if ((p->p_p->ps_flags & PS_PLEDGE) == 0) 1054 return (0); 1055 1056 if ((p->p_p->ps_pledge & (PLEDGE_INET | PLEDGE_UNIX | PLEDGE_DNS | PLEDGE_YPACTIVE))) 1057 return (0); /* may use address */ 1058 if (to == NULL) 1059 return (0); /* behaves just like write */ 1060 return pledge_fail(p, EPERM, PLEDGE_INET); 1061 } 1062 1063 int 1064 pledge_ioctl(struct proc *p, long com, struct file *fp) 1065 { 1066 struct vnode *vp = NULL; 1067 int error = EPERM; 1068 uint64_t pledge; 1069 1070 if ((p->p_p->ps_flags & PS_PLEDGE) == 0) 1071 return (0); 1072 pledge = p->p_p->ps_pledge; 1073 1074 /* 1075 * The ioctl's which are always allowed. 1076 */ 1077 switch (com) { 1078 case FIONREAD: 1079 case FIONBIO: 1080 case FIOCLEX: 1081 case FIONCLEX: 1082 return (0); 1083 } 1084 1085 /* fp != NULL was already checked */ 1086 if (fp->f_type == DTYPE_VNODE) { 1087 vp = fp->f_data; 1088 if (vp->v_type == VBAD) 1089 return (ENOTTY); 1090 } 1091 1092 if ((pledge & PLEDGE_INET)) { 1093 switch (com) { 1094 case SIOCATMARK: 1095 case SIOCGIFGROUP: 1096 if (fp->f_type == DTYPE_SOCKET) 1097 return (0); 1098 break; 1099 } 1100 } 1101 1102 #if NBPFILTER > 0 1103 if ((pledge & PLEDGE_BPF)) { 1104 switch (com) { 1105 case BIOCGSTATS: /* bpf: tcpdump privsep on ^C */ 1106 if (fp->f_type == DTYPE_VNODE && 1107 fp->f_ops->fo_ioctl == vn_ioctl && 1108 vp->v_type == VCHR && 1109 cdevsw[major(vp->v_rdev)].d_open == bpfopen) 1110 return (0); 1111 break; 1112 } 1113 } 1114 #endif /* NBPFILTER > 0 */ 1115 1116 if ((pledge & PLEDGE_TAPE)) { 1117 switch (com) { 1118 case MTIOCGET: 1119 case MTIOCTOP: 1120 /* for pax(1) and such, checking tapes... */ 1121 if (fp->f_type == DTYPE_VNODE && 1122 vp->v_type == VCHR) { 1123 if (vp->v_flag & VISTTY) 1124 return (ENOTTY); 1125 else 1126 return (0); 1127 } 1128 break; 1129 } 1130 } 1131 1132 #if NDRM > 0 1133 if ((pledge & PLEDGE_DRM)) { 1134 if ((fp->f_type == DTYPE_VNODE) && 1135 (vp->v_type == VCHR) && 1136 (cdevsw[major(vp->v_rdev)].d_open == drmopen)) { 1137 error = pledge_ioctl_drm(p, com, vp->v_rdev); 1138 if (error == 0) 1139 return 0; 1140 } 1141 } 1142 #endif /* NDRM > 0 */ 1143 1144 #if NAUDIO > 0 1145 if ((pledge & PLEDGE_AUDIO)) { 1146 switch (com) { 1147 case AUDIO_GETPOS: 1148 case AUDIO_GETPAR: 1149 case AUDIO_SETPAR: 1150 case AUDIO_START: 1151 case AUDIO_STOP: 1152 case AUDIO_MIXER_DEVINFO: 1153 case AUDIO_MIXER_READ: 1154 case AUDIO_MIXER_WRITE: 1155 if (fp->f_type == DTYPE_VNODE && 1156 vp->v_type == VCHR && 1157 cdevsw[major(vp->v_rdev)].d_open == audioopen) 1158 return (0); 1159 } 1160 } 1161 #endif /* NAUDIO > 0 */ 1162 1163 if ((pledge & PLEDGE_DISKLABEL)) { 1164 switch (com) { 1165 case DIOCGDINFO: 1166 case DIOCGPDINFO: 1167 case DIOCRLDINFO: 1168 case DIOCWDINFO: 1169 case BIOCDISK: 1170 case BIOCINQ: 1171 case BIOCINSTALLBOOT: 1172 case BIOCVOL: 1173 if (fp->f_type == DTYPE_VNODE && 1174 ((vp->v_type == VCHR && 1175 cdevsw[major(vp->v_rdev)].d_type == D_DISK) || 1176 (vp->v_type == VBLK && 1177 bdevsw[major(vp->v_rdev)].d_type == D_DISK))) 1178 return (0); 1179 break; 1180 case DIOCMAP: 1181 if (fp->f_type == DTYPE_VNODE && 1182 vp->v_type == VCHR && 1183 cdevsw[major(vp->v_rdev)].d_ioctl == diskmapioctl) 1184 return (0); 1185 break; 1186 } 1187 } 1188 1189 #if NVIDEO > 0 1190 if ((pledge & PLEDGE_VIDEO)) { 1191 switch (com) { 1192 case VIDIOC_QUERYCAP: 1193 case VIDIOC_TRY_FMT: 1194 case VIDIOC_ENUM_FMT: 1195 case VIDIOC_S_FMT: 1196 case VIDIOC_QUERYCTRL: 1197 case VIDIOC_G_CTRL: 1198 case VIDIOC_S_CTRL: 1199 case VIDIOC_G_PARM: 1200 case VIDIOC_S_PARM: 1201 case VIDIOC_REQBUFS: 1202 case VIDIOC_QBUF: 1203 case VIDIOC_DQBUF: 1204 case VIDIOC_QUERYBUF: 1205 case VIDIOC_STREAMON: 1206 case VIDIOC_STREAMOFF: 1207 case VIDIOC_ENUM_FRAMESIZES: 1208 case VIDIOC_ENUM_FRAMEINTERVALS: 1209 case VIDIOC_DQEVENT: 1210 case VIDIOC_ENCODER_CMD: 1211 case VIDIOC_EXPBUF: 1212 case VIDIOC_G_CROP: 1213 case VIDIOC_G_EXT_CTRLS: 1214 case VIDIOC_G_FMT: 1215 case VIDIOC_G_SELECTION: 1216 case VIDIOC_QUERYMENU: 1217 case VIDIOC_SUBSCRIBE_EVENT: 1218 case VIDIOC_S_EXT_CTRLS: 1219 case VIDIOC_S_SELECTION: 1220 case VIDIOC_TRY_DECODER_CMD: 1221 case VIDIOC_TRY_ENCODER_CMD: 1222 if (fp->f_type == DTYPE_VNODE && 1223 vp->v_type == VCHR && 1224 cdevsw[major(vp->v_rdev)].d_open == videoopen) 1225 return (0); 1226 break; 1227 } 1228 } 1229 #endif 1230 1231 #if NPF > 0 1232 if ((pledge & PLEDGE_PF)) { 1233 switch (com) { 1234 case DIOCADDRULE: 1235 case DIOCGETSTATUS: 1236 case DIOCNATLOOK: 1237 case DIOCRADDTABLES: 1238 case DIOCRCLRADDRS: 1239 case DIOCRCLRTABLES: 1240 case DIOCRCLRTSTATS: 1241 case DIOCRGETTSTATS: 1242 case DIOCRSETADDRS: 1243 case DIOCXBEGIN: 1244 case DIOCXCOMMIT: 1245 case DIOCKILLSRCNODES: 1246 if ((fp->f_type == DTYPE_VNODE) && 1247 (vp->v_type == VCHR) && 1248 (cdevsw[major(vp->v_rdev)].d_open == pfopen)) 1249 return (0); 1250 break; 1251 } 1252 } 1253 #endif 1254 1255 if ((pledge & PLEDGE_TTY)) { 1256 switch (com) { 1257 #if NPTY > 0 1258 case PTMGET: 1259 if ((pledge & PLEDGE_RPATH) == 0) 1260 break; 1261 if ((pledge & PLEDGE_WPATH) == 0) 1262 break; 1263 if (fp->f_type != DTYPE_VNODE || vp->v_type != VCHR) 1264 break; 1265 if (cdevsw[major(vp->v_rdev)].d_open != ptmopen) 1266 break; 1267 return (0); 1268 case TIOCUCNTL: /* vmd */ 1269 if ((pledge & PLEDGE_RPATH) == 0) 1270 break; 1271 if ((pledge & PLEDGE_WPATH) == 0) 1272 break; 1273 if (cdevsw[major(vp->v_rdev)].d_open != ptcopen) 1274 break; 1275 return (0); 1276 #endif /* NPTY > 0 */ 1277 case TIOCSPGRP: 1278 if ((pledge & PLEDGE_PROC) == 0) 1279 break; 1280 /* FALLTHROUGH */ 1281 case TIOCFLUSH: /* getty, telnet */ 1282 case TIOCSTART: /* emacs, etc */ 1283 case TIOCGPGRP: 1284 case TIOCGETA: 1285 case TIOCGWINSZ: /* ENOTTY return for non-tty */ 1286 case TIOCSTAT: /* csh */ 1287 if (fp->f_type == DTYPE_VNODE && (vp->v_flag & VISTTY)) 1288 return (0); 1289 return (ENOTTY); 1290 case TIOCSWINSZ: 1291 case TIOCEXT: /* mail, libedit .. */ 1292 case TIOCCBRK: /* cu */ 1293 case TIOCSBRK: /* cu */ 1294 case TIOCCDTR: /* cu */ 1295 case TIOCSDTR: /* cu */ 1296 case TIOCEXCL: /* cu */ 1297 case TIOCSETA: /* cu, ... */ 1298 case TIOCSETAW: /* cu, ... */ 1299 case TIOCSETAF: /* tcsetattr TCSAFLUSH, script */ 1300 case TIOCSCTTY: /* forkpty(3), login_tty(3), ... */ 1301 if (fp->f_type == DTYPE_VNODE && (vp->v_flag & VISTTY)) 1302 return (0); 1303 break; 1304 } 1305 } 1306 1307 if ((pledge & PLEDGE_ROUTE)) { 1308 switch (com) { 1309 case SIOCGIFADDR: 1310 case SIOCGIFAFLAG_IN6: 1311 case SIOCGIFALIFETIME_IN6: 1312 case SIOCGIFDESCR: 1313 case SIOCGIFFLAGS: 1314 case SIOCGIFMETRIC: 1315 case SIOCGIFGMEMB: 1316 case SIOCGIFRDOMAIN: 1317 case SIOCGIFDSTADDR_IN6: 1318 case SIOCGIFNETMASK_IN6: 1319 case SIOCGIFXFLAGS: 1320 case SIOCGNBRINFO_IN6: 1321 case SIOCGIFINFO_IN6: 1322 case SIOCGIFMEDIA: 1323 if (fp->f_type == DTYPE_SOCKET) 1324 return (0); 1325 break; 1326 } 1327 } 1328 1329 if ((pledge & PLEDGE_WROUTE)) { 1330 switch (com) { 1331 case SIOCAIFADDR: 1332 case SIOCDIFADDR: 1333 case SIOCAIFADDR_IN6: 1334 case SIOCDIFADDR_IN6: 1335 if (fp->f_type == DTYPE_SOCKET) 1336 return (0); 1337 break; 1338 case SIOCSIFMTU: 1339 if (fp->f_type == DTYPE_SOCKET) 1340 return (0); 1341 break; 1342 } 1343 } 1344 1345 #if NVMM > 0 1346 if ((pledge & PLEDGE_VMM)) { 1347 if ((fp->f_type == DTYPE_VNODE) && 1348 (vp->v_type == VCHR) && 1349 (cdevsw[major(vp->v_rdev)].d_open == vmmopen)) { 1350 error = pledge_ioctl_vmm(p, com); 1351 if (error == 0) 1352 return 0; 1353 } 1354 } 1355 #endif 1356 1357 return pledge_fail(p, error, PLEDGE_TTY); 1358 } 1359 1360 int 1361 pledge_sockopt(struct proc *p, int set, int level, int optname) 1362 { 1363 uint64_t pledge; 1364 1365 if ((p->p_p->ps_flags & PS_PLEDGE) == 0) 1366 return (0); 1367 pledge = p->p_p->ps_pledge; 1368 1369 /* Always allow these, which are too common to reject */ 1370 switch (level) { 1371 case SOL_SOCKET: 1372 switch (optname) { 1373 case SO_RCVBUF: 1374 case SO_ERROR: 1375 return 0; 1376 } 1377 break; 1378 } 1379 1380 if ((pledge & PLEDGE_WROUTE)) { 1381 switch (level) { 1382 case SOL_SOCKET: 1383 switch (optname) { 1384 case SO_RTABLE: 1385 return (0); 1386 } 1387 } 1388 } 1389 1390 if ((pledge & (PLEDGE_INET|PLEDGE_UNIX|PLEDGE_DNS|PLEDGE_YPACTIVE)) == 0) 1391 return pledge_fail(p, EPERM, PLEDGE_INET); 1392 /* In use by some service libraries */ 1393 switch (level) { 1394 case SOL_SOCKET: 1395 switch (optname) { 1396 case SO_TIMESTAMP: 1397 return 0; 1398 } 1399 break; 1400 } 1401 1402 /* DNS resolver may do these requests */ 1403 if ((pledge & PLEDGE_DNS)) { 1404 switch (level) { 1405 case IPPROTO_IPV6: 1406 switch (optname) { 1407 case IPV6_RECVPKTINFO: 1408 case IPV6_USE_MIN_MTU: 1409 return (0); 1410 } 1411 } 1412 } 1413 1414 /* YP may do these requests */ 1415 if (pledge & PLEDGE_YPACTIVE) { 1416 switch (level) { 1417 case IPPROTO_IP: 1418 switch (optname) { 1419 case IP_PORTRANGE: 1420 return (0); 1421 } 1422 break; 1423 1424 case IPPROTO_IPV6: 1425 switch (optname) { 1426 case IPV6_PORTRANGE: 1427 return (0); 1428 } 1429 break; 1430 } 1431 } 1432 1433 if ((pledge & (PLEDGE_INET|PLEDGE_UNIX)) == 0) 1434 return pledge_fail(p, EPERM, PLEDGE_INET); 1435 switch (level) { 1436 case SOL_SOCKET: 1437 switch (optname) { 1438 case SO_RTABLE: 1439 return pledge_fail(p, EINVAL, PLEDGE_WROUTE); 1440 } 1441 return (0); 1442 } 1443 1444 if ((pledge & PLEDGE_INET) == 0) 1445 return pledge_fail(p, EPERM, PLEDGE_INET); 1446 switch (level) { 1447 case IPPROTO_TCP: 1448 switch (optname) { 1449 case TCP_NODELAY: 1450 case TCP_MD5SIG: 1451 case TCP_SACK_ENABLE: 1452 case TCP_MAXSEG: 1453 case TCP_NOPUSH: 1454 return (0); 1455 } 1456 break; 1457 case IPPROTO_IP: 1458 switch (optname) { 1459 case IP_OPTIONS: 1460 if (!set) 1461 return (0); 1462 break; 1463 case IP_TOS: 1464 case IP_TTL: 1465 case IP_MINTTL: 1466 case IP_IPDEFTTL: 1467 case IP_PORTRANGE: 1468 case IP_RECVDSTADDR: 1469 case IP_RECVDSTPORT: 1470 return (0); 1471 case IP_MULTICAST_IF: 1472 case IP_MULTICAST_TTL: 1473 case IP_MULTICAST_LOOP: 1474 case IP_ADD_MEMBERSHIP: 1475 case IP_DROP_MEMBERSHIP: 1476 if (pledge & PLEDGE_MCAST) 1477 return (0); 1478 break; 1479 } 1480 break; 1481 case IPPROTO_ICMP: 1482 break; 1483 case IPPROTO_IPV6: 1484 switch (optname) { 1485 case IPV6_TCLASS: 1486 case IPV6_UNICAST_HOPS: 1487 case IPV6_MINHOPCOUNT: 1488 case IPV6_RECVHOPLIMIT: 1489 case IPV6_PORTRANGE: 1490 case IPV6_RECVPKTINFO: 1491 case IPV6_RECVDSTPORT: 1492 case IPV6_V6ONLY: 1493 return (0); 1494 case IPV6_MULTICAST_IF: 1495 case IPV6_MULTICAST_HOPS: 1496 case IPV6_MULTICAST_LOOP: 1497 case IPV6_JOIN_GROUP: 1498 case IPV6_LEAVE_GROUP: 1499 if (pledge & PLEDGE_MCAST) 1500 return (0); 1501 break; 1502 } 1503 break; 1504 case IPPROTO_ICMPV6: 1505 break; 1506 } 1507 return pledge_fail(p, EPERM, PLEDGE_INET); 1508 } 1509 1510 int 1511 pledge_socket(struct proc *p, int domain, unsigned int state) 1512 { 1513 uint64_t pledge; 1514 1515 if (!ISSET(p->p_p->ps_flags, PS_PLEDGE)) 1516 return 0; 1517 pledge = p->p_p->ps_pledge; 1518 1519 if (ISSET(state, SS_DNS)) { 1520 if (ISSET(pledge, PLEDGE_DNS)) 1521 return 0; 1522 return pledge_fail(p, EPERM, PLEDGE_DNS); 1523 } 1524 1525 switch (domain) { 1526 case -1: /* accept on any domain */ 1527 return (0); 1528 case AF_INET: 1529 case AF_INET6: 1530 if (ISSET(pledge, PLEDGE_INET) || 1531 ISSET(pledge, PLEDGE_YPACTIVE)) 1532 return 0; 1533 return pledge_fail(p, EPERM, PLEDGE_INET); 1534 1535 case AF_UNIX: 1536 if (ISSET(pledge, PLEDGE_UNIX)) 1537 return 0; 1538 return pledge_fail(p, EPERM, PLEDGE_UNIX); 1539 } 1540 1541 return pledge_fail(p, EINVAL, PLEDGE_INET); 1542 } 1543 1544 int 1545 pledge_flock(struct proc *p) 1546 { 1547 if ((p->p_p->ps_flags & PS_PLEDGE) == 0) 1548 return (0); 1549 1550 if ((p->p_p->ps_pledge & PLEDGE_FLOCK)) 1551 return (0); 1552 return (pledge_fail(p, EPERM, PLEDGE_FLOCK)); 1553 } 1554 1555 int 1556 pledge_swapctl(struct proc *p) 1557 { 1558 if ((p->p_p->ps_flags & PS_PLEDGE) == 0) 1559 return (0); 1560 return (EPERM); 1561 } 1562 1563 /* bsearch over pledgereq. return flags value if found, 0 else */ 1564 uint64_t 1565 pledgereq_flags(const char *req_name) 1566 { 1567 int base = 0, cmp, i, lim; 1568 1569 for (lim = nitems(pledgereq); lim != 0; lim >>= 1) { 1570 i = base + (lim >> 1); 1571 cmp = strcmp(req_name, pledgereq[i].name); 1572 if (cmp == 0) 1573 return (pledgereq[i].flags); 1574 if (cmp > 0) { /* not found before, move right */ 1575 base = i + 1; 1576 lim--; 1577 } /* else move left */ 1578 } 1579 return (0); 1580 } 1581 1582 int 1583 pledge_fcntl(struct proc *p, int cmd) 1584 { 1585 if ((p->p_p->ps_flags & PS_PLEDGE) == 0) 1586 return (0); 1587 if ((p->p_p->ps_pledge & PLEDGE_PROC) == 0 && cmd == F_SETOWN) 1588 return pledge_fail(p, EPERM, PLEDGE_PROC); 1589 return (0); 1590 } 1591 1592 int 1593 pledge_kill(struct proc *p, pid_t pid) 1594 { 1595 if ((p->p_p->ps_flags & PS_PLEDGE) == 0) 1596 return 0; 1597 if (p->p_p->ps_pledge & PLEDGE_PROC) 1598 return 0; 1599 if (pid == 0 || pid == p->p_p->ps_pid) 1600 return 0; 1601 return pledge_fail(p, EPERM, PLEDGE_PROC); 1602 } 1603 1604 int 1605 pledge_protexec(struct proc *p, int prot) 1606 { 1607 if ((p->p_p->ps_flags & PS_PLEDGE) == 0) 1608 return 0; 1609 /* Before kbind(2) call, ld.so and crt may create EXEC mappings */ 1610 if (p->p_p->ps_kbind_addr == 0 && p->p_p->ps_kbind_cookie == 0) 1611 return 0; 1612 if (!(p->p_p->ps_pledge & PLEDGE_PROTEXEC) && (prot & PROT_EXEC)) 1613 return pledge_fail(p, EPERM, PLEDGE_PROTEXEC); 1614 return 0; 1615 } 1616 1617 int 1618 canonpath(const char *input, char *buf, size_t bufsize) 1619 { 1620 const char *p; 1621 char *q; 1622 1623 /* can't canon relative paths, don't bother */ 1624 if (input[0] != '/') { 1625 if (strlcpy(buf, input, bufsize) >= bufsize) 1626 return ENAMETOOLONG; 1627 return 0; 1628 } 1629 1630 p = input; 1631 q = buf; 1632 while (*p && (q - buf < bufsize)) { 1633 if (p[0] == '/' && (p[1] == '/' || p[1] == '\0')) { 1634 p += 1; 1635 1636 } else if (p[0] == '/' && p[1] == '.' && 1637 (p[2] == '/' || p[2] == '\0')) { 1638 p += 2; 1639 1640 } else if (p[0] == '/' && p[1] == '.' && p[2] == '.' && 1641 (p[3] == '/' || p[3] == '\0')) { 1642 p += 3; 1643 if (q != buf) /* "/../" at start of buf */ 1644 while (*--q != '/') 1645 continue; 1646 1647 } else { 1648 *q++ = *p++; 1649 } 1650 } 1651 if ((*p == '\0') && (q - buf < bufsize)) { 1652 *q = 0; 1653 return 0; 1654 } else 1655 return ENAMETOOLONG; 1656 } 1657