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/*-
* Copyright (c) 2008-2010 Robert N. M. Watson
* Copyright (c) 2012 FreeBSD Foundation
* All rights reserved.
*
* This software was developed at the University of Cambridge Computer
* Laboratory with support from a grant from Google, Inc.
*
* Portions of this software were developed by Pawel Jakub Dawidek under
* sponsorship from the FreeBSD Foundation.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
/*
* Definitions for FreeBSD capabilities facility.
*/
#ifndef _SYS_CAPABILITY_H_
#define _SYS_CAPABILITY_H_
#include <sys/cdefs.h>
#include <sys/param.h>
#include <sys/caprights.h>
#include <sys/file.h>
#include <sys/fcntl.h>
#ifndef _KERNEL
#include <stdbool.h>
#endif
#define CAPRIGHT(idx, bit) ((1ULL << (57 + (idx))) | (bit))
/*
* Possible rights on capabilities.
*
* Notes:
* Some system calls don't require a capability in order to perform an
* operation on an fd. These include: close, dup, dup2.
*
* sendfile is authorized using CAP_READ on the file and CAP_WRITE on the
* socket.
*
* mmap() and aio*() system calls will need special attention as they may
* involve reads or writes depending a great deal on context.
*/
/* INDEX 0 */
/*
* General file I/O.
*/
/* Allows for openat(O_RDONLY), read(2), readv(2). */
#define CAP_READ CAPRIGHT(0, 0x0000000000000001ULL)
/* Allows for openat(O_WRONLY | O_APPEND), write(2), writev(2). */
#define CAP_WRITE CAPRIGHT(0, 0x0000000000000002ULL)
/* Allows for lseek(fd, 0, SEEK_CUR). */
#define CAP_SEEK_TELL CAPRIGHT(0, 0x0000000000000004ULL)
/* Allows for lseek(2). */
#define CAP_SEEK (CAP_SEEK_TELL | 0x0000000000000008ULL)
/* Allows for aio_read(2), pread(2), preadv(2). */
#define CAP_PREAD (CAP_SEEK | CAP_READ)
/*
* Allows for aio_write(2), openat(O_WRONLY) (without O_APPEND), pwrite(2),
* pwritev(2).
*/
#define CAP_PWRITE (CAP_SEEK | CAP_WRITE)
/* Allows for mmap(PROT_NONE). */
#define CAP_MMAP CAPRIGHT(0, 0x0000000000000010ULL)
/* Allows for mmap(PROT_READ). */
#define CAP_MMAP_R (CAP_MMAP | CAP_SEEK | CAP_READ)
/* Allows for mmap(PROT_WRITE). */
#define CAP_MMAP_W (CAP_MMAP | CAP_SEEK | CAP_WRITE)
/* Allows for mmap(PROT_EXEC). */
#define CAP_MMAP_X (CAP_MMAP | CAP_SEEK | 0x0000000000000020ULL)
/* Allows for mmap(PROT_READ | PROT_WRITE). */
#define CAP_MMAP_RW (CAP_MMAP_R | CAP_MMAP_W)
/* Allows for mmap(PROT_READ | PROT_EXEC). */
#define CAP_MMAP_RX (CAP_MMAP_R | CAP_MMAP_X)
/* Allows for mmap(PROT_WRITE | PROT_EXEC). */
#define CAP_MMAP_WX (CAP_MMAP_W | CAP_MMAP_X)
/* Allows for mmap(PROT_READ | PROT_WRITE | PROT_EXEC). */
#define CAP_MMAP_RWX (CAP_MMAP_R | CAP_MMAP_W | CAP_MMAP_X)
/* Allows for openat(O_CREAT). */
#define CAP_CREATE CAPRIGHT(0, 0x0000000000000040ULL)
/* Allows for openat(O_EXEC) and fexecve(2) in turn. */
#define CAP_FEXECVE CAPRIGHT(0, 0x0000000000000080ULL)
/* Allows for openat(O_SYNC), openat(O_FSYNC), fsync(2), aio_fsync(2). */
#define CAP_FSYNC CAPRIGHT(0, 0x0000000000000100ULL)
/* Allows for openat(O_TRUNC), ftruncate(2). */
#define CAP_FTRUNCATE CAPRIGHT(0, 0x0000000000000200ULL)
/* Lookups - used to constrain *at() calls. */
#define CAP_LOOKUP CAPRIGHT(0, 0x0000000000000400ULL)
/* VFS methods. */
/* Allows for fchdir(2). */
#define CAP_FCHDIR CAPRIGHT(0, 0x0000000000000800ULL)
/* Allows for fchflags(2). */
#define CAP_FCHFLAGS CAPRIGHT(0, 0x0000000000001000ULL)
/* Allows for fchflags(2) and chflagsat(2). */
#define CAP_CHFLAGSAT (CAP_FCHFLAGS | CAP_LOOKUP)
/* Allows for fchmod(2). */
#define CAP_FCHMOD CAPRIGHT(0, 0x0000000000002000ULL)
/* Allows for fchmod(2) and fchmodat(2). */
#define CAP_FCHMODAT (CAP_FCHMOD | CAP_LOOKUP)
/* Allows for fchown(2). */
#define CAP_FCHOWN CAPRIGHT(0, 0x0000000000004000ULL)
/* Allows for fchown(2) and fchownat(2). */
#define CAP_FCHOWNAT (CAP_FCHOWN | CAP_LOOKUP)
/* Allows for fcntl(2). */
#define CAP_FCNTL CAPRIGHT(0, 0x0000000000008000ULL)
/*
* Allows for flock(2), openat(O_SHLOCK), openat(O_EXLOCK),
* fcntl(F_SETLK_REMOTE), fcntl(F_SETLKW), fcntl(F_SETLK), fcntl(F_GETLK).
*/
#define CAP_FLOCK CAPRIGHT(0, 0x0000000000010000ULL)
/* Allows for fpathconf(2). */
#define CAP_FPATHCONF CAPRIGHT(0, 0x0000000000020000ULL)
/* Allows for UFS background-fsck operations. */
#define CAP_FSCK CAPRIGHT(0, 0x0000000000040000ULL)
/* Allows for fstat(2). */
#define CAP_FSTAT CAPRIGHT(0, 0x0000000000080000ULL)
/* Allows for fstat(2), fstatat(2) and faccessat(2). */
#define CAP_FSTATAT (CAP_FSTAT | CAP_LOOKUP)
/* Allows for fstatfs(2). */
#define CAP_FSTATFS CAPRIGHT(0, 0x0000000000100000ULL)
/* Allows for futimes(2). */
#define CAP_FUTIMES CAPRIGHT(0, 0x0000000000200000ULL)
/* Allows for futimes(2) and futimesat(2). */
#define CAP_FUTIMESAT (CAP_FUTIMES | CAP_LOOKUP)
/* Allows for linkat(2) and renameat(2) (destination directory descriptor). */
#define CAP_LINKAT (CAP_LOOKUP | 0x0000000000400000ULL)
/* Allows for mkdirat(2). */
#define CAP_MKDIRAT (CAP_LOOKUP | 0x0000000000800000ULL)
/* Allows for mkfifoat(2). */
#define CAP_MKFIFOAT (CAP_LOOKUP | 0x0000000001000000ULL)
/* Allows for mknodat(2). */
#define CAP_MKNODAT (CAP_LOOKUP | 0x0000000002000000ULL)
/* Allows for renameat(2). */
#define CAP_RENAMEAT (CAP_LOOKUP | 0x0000000004000000ULL)
/* Allows for symlinkat(2). */
#define CAP_SYMLINKAT (CAP_LOOKUP | 0x0000000008000000ULL)
/*
* Allows for unlinkat(2) and renameat(2) if destination object exists and
* will be removed.
*/
#define CAP_UNLINKAT (CAP_LOOKUP | 0x0000000010000000ULL)
/* Socket operations. */
/* Allows for accept(2) and accept4(2). */
#define CAP_ACCEPT CAPRIGHT(0, 0x0000000020000000ULL)
/* Allows for bind(2). */
#define CAP_BIND CAPRIGHT(0, 0x0000000040000000ULL)
/* Allows for connect(2). */
#define CAP_CONNECT CAPRIGHT(0, 0x0000000080000000ULL)
/* Allows for getpeername(2). */
#define CAP_GETPEERNAME CAPRIGHT(0, 0x0000000100000000ULL)
/* Allows for getsockname(2). */
#define CAP_GETSOCKNAME CAPRIGHT(0, 0x0000000200000000ULL)
/* Allows for getsockopt(2). */
#define CAP_GETSOCKOPT CAPRIGHT(0, 0x0000000400000000ULL)
/* Allows for listen(2). */
#define CAP_LISTEN CAPRIGHT(0, 0x0000000800000000ULL)
/* Allows for sctp_peeloff(2). */
#define CAP_PEELOFF CAPRIGHT(0, 0x0000001000000000ULL)
#define CAP_RECV CAP_READ
#define CAP_SEND CAP_WRITE
/* Allows for setsockopt(2). */
#define CAP_SETSOCKOPT CAPRIGHT(0, 0x0000002000000000ULL)
/* Allows for shutdown(2). */
#define CAP_SHUTDOWN CAPRIGHT(0, 0x0000004000000000ULL)
/* Allows for bindat(2) on a directory descriptor. */
#define CAP_BINDAT (CAP_LOOKUP | 0x0000008000000000ULL)
/* Allows for connectat(2) on a directory descriptor. */
#define CAP_CONNECTAT (CAP_LOOKUP | 0x0000010000000000ULL)
#define CAP_SOCK_CLIENT \
(CAP_CONNECT | CAP_GETPEERNAME | CAP_GETSOCKNAME | CAP_GETSOCKOPT | \
CAP_PEELOFF | CAP_RECV | CAP_SEND | CAP_SETSOCKOPT | CAP_SHUTDOWN)
#define CAP_SOCK_SERVER \
(CAP_ACCEPT | CAP_BIND | CAP_GETPEERNAME | CAP_GETSOCKNAME | \
CAP_GETSOCKOPT | CAP_LISTEN | CAP_PEELOFF | CAP_RECV | CAP_SEND | \
CAP_SETSOCKOPT | CAP_SHUTDOWN)
/* All used bits for index 0. */
#define CAP_ALL0 CAPRIGHT(0, 0x0000007FFFFFFFFFULL)
/* Available bits for index 0. */
#define CAP_UNUSED0_40 CAPRIGHT(0, 0x0000008000000000ULL)
/* ... */
#define CAP_UNUSED0_57 CAPRIGHT(0, 0x0100000000000000ULL)
/* INDEX 1 */
/* Mandatory Access Control. */
/* Allows for mac_get_fd(3). */
#define CAP_MAC_GET CAPRIGHT(1, 0x0000000000000001ULL)
/* Allows for mac_set_fd(3). */
#define CAP_MAC_SET CAPRIGHT(1, 0x0000000000000002ULL)
/* Methods on semaphores. */
#define CAP_SEM_GETVALUE CAPRIGHT(1, 0x0000000000000004ULL)
#define CAP_SEM_POST CAPRIGHT(1, 0x0000000000000008ULL)
#define CAP_SEM_WAIT CAPRIGHT(1, 0x0000000000000010ULL)
/* Allows select(2) and poll(2) on descriptor. */
#define CAP_EVENT CAPRIGHT(1, 0x0000000000000020ULL)
/* Allows for kevent(2) on kqueue descriptor with eventlist != NULL. */
#define CAP_KQUEUE_EVENT CAPRIGHT(1, 0x0000000000000040ULL)
/* Strange and powerful rights that should not be given lightly. */
/* Allows for ioctl(2). */
#define CAP_IOCTL CAPRIGHT(1, 0x0000000000000080ULL)
#define CAP_TTYHOOK CAPRIGHT(1, 0x0000000000000100ULL)
/* Process management via process descriptors. */
/* Allows for pdgetpid(2). */
#define CAP_PDGETPID CAPRIGHT(1, 0x0000000000000200ULL)
/* Allows for pdwait4(2). */
#define CAP_PDWAIT CAPRIGHT(1, 0x0000000000000400ULL)
/* Allows for pdkill(2). */
#define CAP_PDKILL CAPRIGHT(1, 0x0000000000000800ULL)
/* Extended attributes. */
/* Allows for extattr_delete_fd(2). */
#define CAP_EXTATTR_DELETE CAPRIGHT(1, 0x0000000000001000ULL)
/* Allows for extattr_get_fd(2). */
#define CAP_EXTATTR_GET CAPRIGHT(1, 0x0000000000002000ULL)
/* Allows for extattr_list_fd(2). */
#define CAP_EXTATTR_LIST CAPRIGHT(1, 0x0000000000004000ULL)
/* Allows for extattr_set_fd(2). */
#define CAP_EXTATTR_SET CAPRIGHT(1, 0x0000000000008000ULL)
/* Access Control Lists. */
/* Allows for acl_valid_fd_np(3). */
#define CAP_ACL_CHECK CAPRIGHT(1, 0x0000000000010000ULL)
/* Allows for acl_delete_fd_np(3). */
#define CAP_ACL_DELETE CAPRIGHT(1, 0x0000000000020000ULL)
/* Allows for acl_get_fd(3) and acl_get_fd_np(3). */
#define CAP_ACL_GET CAPRIGHT(1, 0x0000000000040000ULL)
/* Allows for acl_set_fd(3) and acl_set_fd_np(3). */
#define CAP_ACL_SET CAPRIGHT(1, 0x0000000000080000ULL)
/* Allows for kevent(2) on kqueue descriptor with changelist != NULL. */
#define CAP_KQUEUE_CHANGE CAPRIGHT(1, 0x0000000000100000ULL)
#define CAP_KQUEUE (CAP_KQUEUE_EVENT | CAP_KQUEUE_CHANGE)
/* All used bits for index 1. */
#define CAP_ALL1 CAPRIGHT(1, 0x00000000001FFFFFULL)
/* Available bits for index 1. */
#define CAP_UNUSED1_22 CAPRIGHT(1, 0x0000000000200000ULL)
/* ... */
#define CAP_UNUSED1_57 CAPRIGHT(1, 0x0100000000000000ULL)
/* Backward compatibility. */
#define CAP_POLL_EVENT CAP_EVENT
#define CAP_ALL(rights) do { \
(rights)->cr_rights[0] = \
((uint64_t)CAP_RIGHTS_VERSION << 62) | CAP_ALL0; \
(rights)->cr_rights[1] = CAP_ALL1; \
} while (0)
#define CAP_NONE(rights) do { \
(rights)->cr_rights[0] = \
((uint64_t)CAP_RIGHTS_VERSION << 62) | CAPRIGHT(0, 0ULL); \
(rights)->cr_rights[1] = CAPRIGHT(1, 0ULL); \
} while (0)
#define CAPRVER(right) ((int)((right) >> 62))
#define CAPVER(rights) CAPRVER((rights)->cr_rights[0])
#define CAPARSIZE(rights) (CAPVER(rights) + 2)
#define CAPIDXBIT(right) ((int)(((right) >> 57) & 0x1F))
/*
* Allowed fcntl(2) commands.
*/
#define CAP_FCNTL_GETFL (1 << F_GETFL)
#define CAP_FCNTL_SETFL (1 << F_SETFL)
#if __BSD_VISIBLE || __XSI_VISIBLE || __POSIX_VISIBLE >= 200112
#define CAP_FCNTL_GETOWN (1 << F_GETOWN)
#define CAP_FCNTL_SETOWN (1 << F_SETOWN)
#endif
#if __BSD_VISIBLE || __XSI_VISIBLE || __POSIX_VISIBLE >= 200112
#define CAP_FCNTL_ALL (CAP_FCNTL_GETFL | CAP_FCNTL_SETFL | \
CAP_FCNTL_GETOWN | CAP_FCNTL_SETOWN)
#else
#define CAP_FCNTL_ALL (CAP_FCNTL_GETFL | CAP_FCNTL_SETFL)
#endif
#define CAP_IOCTLS_ALL SSIZE_MAX
#define cap_rights_init(...) \
__cap_rights_init(CAP_RIGHTS_VERSION, __VA_ARGS__, 0ULL)
cap_rights_t *__cap_rights_init(int version, cap_rights_t *rights, ...);
#define cap_rights_set(rights, ...) \
__cap_rights_set((rights), __VA_ARGS__, 0ULL)
cap_rights_t *__cap_rights_set(cap_rights_t *rights, ...);
#define cap_rights_clear(rights, ...) \
__cap_rights_clear((rights), __VA_ARGS__, 0ULL)
cap_rights_t *__cap_rights_clear(cap_rights_t *rights, ...);
#define cap_rights_is_set(rights, ...) \
__cap_rights_is_set((rights), __VA_ARGS__, 0ULL)
bool __cap_rights_is_set(const cap_rights_t *rights, ...);
bool cap_rights_is_valid(const cap_rights_t *rights);
cap_rights_t *cap_rights_merge(cap_rights_t *dst, const cap_rights_t *src);
cap_rights_t *cap_rights_remove(cap_rights_t *dst, const cap_rights_t *src);
bool cap_rights_contains(const cap_rights_t *big, const cap_rights_t *little);
#ifdef _KERNEL
#include <sys/systm.h>
#define IN_CAPABILITY_MODE(td) ((td->td_ucred->cr_flags & CRED_FLAG_CAPMODE) != 0)
struct filedesc;
struct filedescent;
/*
* Test whether a capability grants the requested rights.
*/
int cap_check(const cap_rights_t *havep, const cap_rights_t *needp);
/*
* Convert capability rights into VM access flags.
*/
u_char cap_rights_to_vmprot(cap_rights_t *havep);
/*
* For the purposes of procstat(1) and similar tools, allow kern_descrip.c to
* extract the rights from a capability.
*/
cap_rights_t *cap_rights_fde(struct filedescent *fde);
cap_rights_t *cap_rights(struct filedesc *fdp, int fd);
int cap_ioctl_check(struct filedesc *fdp, int fd, u_long cmd);
int cap_fcntl_check_fde(struct filedescent *fde, int cmd);
int cap_fcntl_check(struct filedesc *fdp, int fd, int cmd);
#else /* !_KERNEL */
__BEGIN_DECLS
/*
* cap_enter(): Cause the process to enter capability mode, which will
* prevent it from directly accessing global namespaces. System calls will
* be limited to process-local, process-inherited, or file descriptor
* operations. If already in capability mode, a no-op.
*/
int cap_enter(void);
/*
* Are we sandboxed (in capability mode)?
* This is a libc wrapper around the cap_getmode(2) system call.
*/
bool cap_sandboxed(void);
/*
* cap_getmode(): Are we in capability mode?
*/
int cap_getmode(u_int *modep);
/*
* Limits capability rights for the given descriptor (CAP_*).
*/
int cap_rights_limit(int fd, const cap_rights_t *rights);
/*
* Returns capability rights for the given descriptor.
*/
#define cap_rights_get(fd, rights) __cap_rights_get(CAP_RIGHTS_VERSION, (fd), (rights))
int __cap_rights_get(int version, int fd, cap_rights_t *rightsp);
/*
* Limits allowed ioctls for the given descriptor.
*/
int cap_ioctls_limit(int fd, const unsigned long *cmds, size_t ncmds);
/*
* Returns array of allowed ioctls for the given descriptor.
* If all ioctls are allowed, the cmds array is not populated and
* the function returns CAP_IOCTLS_ALL.
*/
ssize_t cap_ioctls_get(int fd, unsigned long *cmds, size_t maxcmds);
/*
* Limits allowed fcntls for the given descriptor (CAP_FCNTL_*).
*/
int cap_fcntls_limit(int fd, uint32_t fcntlrights);
/*
* Returns bitmask of allowed fcntls for the given descriptor.
*/
int cap_fcntls_get(int fd, uint32_t *fcntlrightsp);
__END_DECLS
#endif /* !_KERNEL */
#endif /* !_SYS_CAPABILITY_H_ */
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