1## 2## Copyright (c) 2008-2010 Robert N. M. Watson 3## All rights reserved. 4## 5## This software was developed at the University of Cambridge Computer 6## Laboratory with support from a grant from Google, Inc. 7## 8## Redistribution and use in source and binary forms, with or without 9## modification, are permitted provided that the following conditions 10## are met: 11## 1. Redistributions of source code must retain the above copyright 12## notice, this list of conditions and the following disclaimer. 13## 2. Redistributions in binary form must reproduce the above copyright 14## notice, this list of conditions and the following disclaimer in the 15## documentation and/or other materials provided with the distribution. 16## 17## THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 18## ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19## IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20## ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 21## FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22## DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23## OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24## HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25## LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26## OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27## SUCH DAMAGE. 28## 29## List of system calls enabled in capability mode, one name per line. 30## 31## Notes: 32## - sys_exit(2), abort2(2) and close(2) are very important. 33## - Sorted alphabetically, please keep it that way. 34## 35## $FreeBSD$ 36## 37 38## 39## Allow ACL and MAC label operations by file descriptor, subject to 40## capability rights. Allow MAC label operations on the current process but 41## we will need to scope __mac_get_pid(2). 42## 43__acl_aclcheck_fd 44__acl_delete_fd 45__acl_get_fd 46__acl_set_fd 47__mac_get_fd 48#__mac_get_pid 49__mac_get_proc 50__mac_set_fd 51__mac_set_proc 52 53## 54## Allow sysctl(2) as we scope internal to the call; this is a global 55## namespace, but there are several critical sysctls required for almost 56## anything to run, such as hw.pagesize. For now that policy lives in the 57## kernel for performance and simplicity, but perhaps it could move to a 58## proxying daemon in userspace. 59## 60__sysctl 61 62## 63## Allow umtx operations as these are scoped by address space. 64## 65## XXRW: Need to check this very carefully. 66## 67_umtx_lock 68_umtx_op 69_umtx_unlock 70 71## 72## Allow process termination using abort2(2). 73## 74abort2 75 76## 77## Allow accept(2) since it doesn't manipulate namespaces directly, rather 78## relies on existing bindings on a socket, subject to capability rights. 79## 80accept 81accept4 82 83## 84## Allow AIO operations by file descriptor, subject to capability rights. 85## 86aio_cancel 87aio_error 88aio_fsync 89aio_read 90aio_return 91aio_suspend 92aio_waitcomplete 93aio_write 94 95## 96## audit(2) is a global operation, submitting to the global trail, but it is 97## controlled by privilege, and it might be useful to be able to submit 98## records from sandboxes. For now, disallow, but we may want to think about 99## providing some sort of proxy service for this. 100## 101#audit 102 103## 104## Allow bindat(2). 105## 106bindat 107 108## 109## Allow capability mode and capability system calls. 110## 111cap_enter 112cap_fcntls_get 113cap_fcntls_limit 114cap_getmode 115cap_ioctls_get 116cap_ioctls_limit 117__cap_rights_get 118cap_rights_limit 119 120## 121## Allow read-only clock operations. 122## 123clock_getres 124clock_gettime 125 126## 127## Always allow file descriptor close(2). 128## 129close 130closefrom 131 132## 133## Allow connectat(2). 134## 135connectat 136 137## 138## cpuset(2) and related calls require scoping by process, but should 139## eventually be allowed, at least in the current process case. 140## 141#cpuset 142#cpuset_getaffinity 143#cpuset_getid 144#cpuset_setaffinity 145#cpuset_setid 146 147## 148## Always allow dup(2) and dup2(2) manipulation of the file descriptor table. 149## 150dup 151dup2 152 153## 154## Allow extended attribute operations by file descriptor, subject to 155## capability rights. 156## 157extattr_delete_fd 158extattr_get_fd 159extattr_list_fd 160extattr_set_fd 161 162## 163## Allow changing file flags, mode, and owner by file descriptor, subject to 164## capability rights. 165## 166fchflags 167fchmod 168fchown 169 170## 171## For now, allow fcntl(2), subject to capability rights, but this probably 172## needs additional scoping. 173## 174fcntl 175 176## 177## Allow fexecve(2), subject to capability rights. We perform some scoping, 178## such as disallowing privilege escalation. 179## 180fexecve 181 182## 183## Allow flock(2), subject to capability rights. 184## 185flock 186 187## 188## Allow fork(2), even though it returns pids -- some applications seem to 189## prefer this interface. 190## 191fork 192 193## 194## Allow fpathconf(2), subject to capability rights. 195## 196fpathconf 197 198## 199## Allow various file descriptor-based I/O operations, subject to capability 200## rights. 201## 202freebsd6_ftruncate 203freebsd6_lseek 204freebsd6_mmap 205freebsd6_pread 206freebsd6_pwrite 207 208## 209## Allow querying file and file system state with fstat(2) and fstatfs(2), 210## subject to capability rights. 211## 212fstat 213fstatfs 214 215## 216## Allow further file descriptor-based I/O operations, subject to capability 217## rights. 218## 219fsync 220ftruncate 221 222## 223## Allow futimes(2), subject to capability rights. 224## 225futimes 226 227## 228## Allow querying process audit state, subject to normal access control. 229## 230getaudit 231getaudit_addr 232getauid 233 234## 235## Allow thread context management with getcontext(2). 236## 237getcontext 238 239## 240## Allow directory I/O on a file descriptor, subject to capability rights. 241## Originally we had separate capabilities for directory-specific read 242## operations, but on BSD we allow reading the raw directory data, so we just 243## rely on CAP_READ now. 244## 245getdents 246getdirentries 247 248## 249## Allow querying certain trivial global state. 250## 251getdomainname 252 253## 254## Allow querying current process credential state. 255## 256getegid 257geteuid 258 259## 260## Allow querying certain trivial global state. 261## 262gethostid 263gethostname 264 265## 266## Allow querying per-process timer. 267## 268getitimer 269 270## 271## Allow querying current process credential state. 272## 273getgid 274getgroups 275getlogin 276 277## 278## Allow querying certain trivial global state. 279## 280getpagesize 281getpeername 282 283## 284## Allow querying certain per-process scheduling, resource limit, and 285## credential state. 286## 287## XXXRW: getpgid(2) needs scoping. It's not clear if it's worth scoping 288## getppid(2). getpriority(2) needs scoping. getrusage(2) needs scoping. 289## getsid(2) needs scoping. 290## 291getpgid 292getpgrp 293getpid 294getppid 295getpriority 296getresgid 297getresuid 298getrlimit 299getrusage 300getsid 301 302## 303## Allow querying socket state, subject to capability rights. 304## 305## XXXRW: getsockopt(2) may need more attention. 306## 307getsockname 308getsockopt 309 310## 311## Allow querying the global clock. 312## 313gettimeofday 314 315## 316## Allow querying current process credential state. 317## 318getuid 319 320## 321## Allow ioctl(2), which hopefully will be limited by applications only to 322## required commands with cap_ioctls_limit(2) syscall. 323## 324ioctl 325 326## 327## Allow querying current process credential state. 328## 329issetugid 330 331## 332## Allow kevent(2), as we will authorize based on capability rights on the 333## target descriptor. 334## 335kevent 336 337## 338## Allow kill(2), as we allow the process to send signals only to himself. 339## 340kill 341 342## 343## Allow message queue operations on file descriptors, subject to capability 344## rights. 345## 346kmq_notify 347kmq_setattr 348kmq_timedreceive 349kmq_timedsend 350 351## 352## Allow kqueue(2), we will control use. 353## 354kqueue 355 356## 357## Allow managing per-process timers. 358## 359ktimer_create 360ktimer_delete 361ktimer_getoverrun 362ktimer_gettime 363ktimer_settime 364 365## 366## We can't allow ktrace(2) because it relies on a global namespace, but we 367## might want to introduce an fktrace(2) of some sort. 368## 369#ktrace 370 371## 372## Allow AIO operations by file descriptor, subject to capability rights. 373## 374lio_listio 375 376## 377## Allow listen(2), subject to capability rights. 378## 379## XXXRW: One might argue this manipulates a global namespace. 380## 381listen 382 383## 384## Allow I/O-related file descriptors, subject to capability rights. 385## 386lseek 387 388## 389## Allow MAC label operations by file descriptor, subject to capability 390## rights. 391## 392mac_get_fd 393mac_set_fd 394 395## 396## Allow simple VM operations on the current process. 397## 398madvise 399mincore 400minherit 401mlock 402mlockall 403 404## 405## Allow memory mapping a file descriptor, and updating protections, subject 406## to capability rights. 407## 408mmap 409mprotect 410 411## 412## Allow simple VM operations on the current process. 413## 414msync 415munlock 416munlockall 417munmap 418 419## 420## Allow the current process to sleep. 421## 422nanosleep 423 424## 425## Allow querying the global clock. 426## 427ntp_gettime 428 429## 430## Allow AIO operations by file descriptor, subject to capability rights. 431## 432oaio_read 433oaio_write 434 435## 436## Allow simple VM operations on the current process. 437## 438obreak 439 440## 441## Allow AIO operations by file descriptor, subject to capability rights. 442## 443olio_listio 444 445## 446## Operations relative to directory capabilities. 447## 448chflagsat 449faccessat 450fchmodat 451fchownat 452fstatat 453futimesat 454linkat 455mkdirat 456mkfifoat 457mknodat 458openat 459readlinkat 460renameat 461symlinkat 462unlinkat 463 464## 465## Allow entry into open(2). This system call will fail, since access to the 466## global file namespace has been disallowed, but allowing entry into the 467## syscall means that an audit trail will be generated (which is also very 468## useful for debugging). 469## 470open 471 472## 473## Allow poll(2), which will be scoped by capability rights. 474## 475## XXXRW: Perhaps we don't need the OpenBSD version? 476## XXXRW: We don't yet do that scoping. 477## 478openbsd_poll 479 480## 481## Process descriptor-related system calls are allowed. 482## 483pdfork 484pdgetpid 485pdkill 486#pdwait4 # not yet implemented 487 488## 489## Allow pipe(2). 490## 491pipe 492pipe2 493 494## 495## Allow poll(2), which will be scoped by capability rights. 496## XXXRW: We don't yet do that scoping. 497## 498poll 499 500## 501## Allow I/O-related file descriptors, subject to capability rights. 502## 503pread 504preadv 505 506## 507## Allow access to profiling state on the current process. 508## 509profil 510 511## 512## Disallow ptrace(2) for now, but we do need debugging facilities in 513## capability mode, so we will want to revisit this, possibly by scoping its 514## operation. 515## 516#ptrace 517 518## 519## Allow I/O-related file descriptors, subject to capability rights. 520## 521pwrite 522pwritev 523read 524readv 525recv 526recvfrom 527recvmsg 528 529## 530## Allow real-time scheduling primitives to be used. 531## 532## XXXRW: These require scoping. 533## 534rtprio 535rtprio_thread 536 537## 538## Allow simple VM operations on the current process. 539## 540sbrk 541 542## 543## Allow querying trivial global scheduler state. 544## 545sched_get_priority_max 546sched_get_priority_min 547 548## 549## Allow various thread/process scheduler operations. 550## 551## XXXRW: Some of these require further scoping. 552## 553sched_getparam 554sched_getscheduler 555sched_rr_getinterval 556sched_setparam 557sched_setscheduler 558sched_yield 559 560## 561## Allow I/O-related file descriptors, subject to capability rights. 562## 563sctp_generic_recvmsg 564sctp_generic_sendmsg 565sctp_generic_sendmsg_iov 566sctp_peeloff 567 568## 569## Allow select(2), which will be scoped by capability rights. 570## 571## XXXRW: But is it? 572## 573select 574 575## 576## Allow I/O-related file descriptors, subject to capability rights. Use of 577## explicit addresses here is restricted by the system calls themselves. 578## 579send 580sendfile 581sendmsg 582sendto 583 584## 585## Allow setting per-process audit state, which is controlled separately by 586## privileges. 587## 588setaudit 589setaudit_addr 590setauid 591 592## 593## Allow setting thread context. 594## 595setcontext 596 597## 598## Allow setting current process credential state, which is controlled 599## separately by privilege. 600## 601setegid 602seteuid 603setgid 604 605## 606## Allow use of the process interval timer. 607## 608setitimer 609 610## 611## Allow setpriority(2). 612## 613## XXXRW: Requires scoping. 614## 615setpriority 616 617## 618## Allow setting current process credential state, which is controlled 619## separately by privilege. 620## 621setregid 622setresgid 623setresuid 624setreuid 625 626## 627## Allow setting process resource limits with setrlimit(2). 628## 629setrlimit 630 631## 632## Allow creating a new session with setsid(2). 633## 634setsid 635 636## 637## Allow setting socket options with setsockopt(2), subject to capability 638## rights. 639## 640## XXXRW: Might require scoping. 641## 642setsockopt 643 644## 645## Allow setting current process credential state, which is controlled 646## separately by privilege. 647## 648setuid 649 650## 651## shm_open(2) is scoped so as to allow only access to new anonymous objects. 652## 653shm_open 654 655## 656## Allow I/O-related file descriptors, subject to capability rights. 657## 658shutdown 659 660## 661## Allow signal control on current process. 662## 663sigaction 664sigaltstack 665sigblock 666sigpending 667sigprocmask 668sigqueue 669sigreturn 670sigsetmask 671sigstack 672sigsuspend 673sigtimedwait 674sigvec 675sigwaitinfo 676 677## 678## Allow creating new socket pairs with socket(2) and socketpair(2). 679## 680socket 681socketpair 682 683## 684## Allow simple VM operations on the current process. 685## 686## XXXRW: Kernel doesn't implement this, so drop? 687## 688sstk 689 690## 691## Do allow sync(2) for now, but possibly shouldn't. 692## 693sync 694 695## 696## Always allow process termination with sys_exit(2). 697## 698sys_exit 699 700## 701## sysarch(2) does rather diverse things, but is required on at least i386 702## in order to configure per-thread data. As such, it's scoped on each 703## architecture. 704## 705sysarch 706 707## 708## Allow thread operations operating only on current process. 709## 710thr_create 711thr_exit 712thr_kill 713 714## 715## Disallow thr_kill2(2), as it may operate beyond the current process. 716## 717## XXXRW: Requires scoping. 718## 719#thr_kill2 720 721## 722## Allow thread operations operating only on current process. 723## 724thr_new 725thr_self 726thr_set_name 727thr_suspend 728thr_wake 729 730## 731## Allow manipulation of the current process umask with umask(2). 732## 733umask 734 735## 736## Allow submitting of process trace entries with utrace(2). 737## 738utrace 739 740## 741## Allow generating UUIDs with uuidgen(2). 742## 743uuidgen 744 745## 746## Allow I/O-related file descriptors, subject to capability rights. 747## 748write 749writev 750 751## 752## Allow processes to yield(2). 753## 754yield 755