.\" written by Andrew Morgan <morgan@kernel.org>
.\" may be distributed as per GPL
.\" Modified by David A. Wheeler <dwheeler@ida.org>
.\" Modified 2004-05-27, mtk
.\" Modified 2004-06-21, aeb
.\" Modified 2008-04-28, morgan of kernel.org
.\"     Update in line with addition of file capabilities and
.\"     64-bit capability sets in kernel 2.6.2[45].
.\" Modified 2009-01-26, andi kleen
.\"
.\" Japanese Version Copyright (c) 1999 HANATAKA Shinya
.\"         all rights reserved.
.\" Translated 1999-12-26, HANATAKA Shinya <hanataka@abyss.rim.or.jp>
.\" Updated & Modified 2005-02-03, Yuichi SATO <ysato444@yahoo.co.jp>
.\" Updated & Modified 2006-01-31, Akihiro MOTOKI <amotoki@dd.iij4u.or.jp>
.\" Updated & Modified 2006-07-23, Akihiro MOTOKI, LDP v2.36
.\" Updated & Modified 2008-08-11, Akihiro MOTOKI, LDP v3.05
.\" Updated 2009-02-24, Akihiro MOTOKI, LDP v3.19
.\"
.\"WORD:	capability		ѥӥƥ
.\"WORD:	effective capability	¸ѥӥƥ
.\"WORD:	inheritable capabilit	Ѿǽѥӥƥ
.\"WORD:	permitted capabily	ĥѥӥƥ
.\"
.TH CAPGET 2 2009-01-26 "Linux" "Linux Programmer's Manual"
.SH ̾
capget, capset \- åɤΥѥӥƥ/
.SH 
.B #undef _POSIX_SOURCE
.br
.B #include <sys/capability.h>
.sp
.BI "int capget(cap_user_header_t " hdrp ", cap_user_data_t " datap );
.sp
.BI "int capset(cap_user_header_t " hdrp ", const cap_user_data_t " datap );
.SH 
Linux 2.2 ǡѡ桼 (root) θ¤ϡ̤Υѥӥƥ
(capabilities) ؤʬ䤵졢νȤɽ褦ˤʤä
ƥåɤϡּ¸ѥӥƥ (effective capability) νפ
ˤäƸߤɤ¹Բǽ̤Ǥ롣
ޤƥåɤϡ
ַѾǽѥӥƥ (inheritable capability) νפ
ֵĥѥӥƥ (permitted capability) νפġ
ַѾǽѥӥƥνפ
.BR execve (2)
̤ϤȤǤ륱ѥӥƥνǤꡢ
ֵĥѥӥƥ (permitted capability) νפ
¸ѥӥƥѾǽѥӥƥȤͭˤǤ
ѥӥƥꤹΤǤ롣
.PP
ĤδؿϥåɤΥѥӥƥꤷꤹ뤿
Υͥ륤󥿡եǤ롣
Υƥॳ Linux ͭǤȤǤʤ
ͥ API ѹ뤫⤷줺
ؿλˡ (ä
.I cap_user_*_t
Ȥ) ϥͥΥӥ˳ĥ뤫⤷ʤ
ΥץϤΤޤư롣
.sp
ܿΤ륤󥿡ե
.BR cap_set_proc (3)

.BR cap_get_proc (3)
Ǥ롣
ǽʤХץꥱϤδؿѤ٤Ǥ롣
ץꥱ Linux ĥѤˤϡñ
Ȥ륤󥿡եǤ
.BR capsetp (3)

.BR capgetp (3)
Ѥ٤Ǥ롣
.SS ߤξܺ
ߤΥͥξܺ٤ˤĤդҤ٤Ƥ
¤ΤϰʲΤ褦롣
.sp
.nf
.in +4n
#define _LINUX_CAPABILITY_VERSION_1  0x19980330
#define _LINUX_CAPABILITY_U32S_1     1

#define _LINUX_CAPABILITY_VERSION_2  0x20071026
#define _LINUX_CAPABILITY_U32S_2     2

typedef struct __user_cap_header_struct {
   __u32 version;
   int pid;
} *cap_user_header_t;

typedef struct __user_cap_data_struct {
   __u32 effective;
   __u32 permitted;
   __u32 inheritable;
} *cap_user_data_t;
.fi
.in -4n
.sp
.I effective, permitted, inheritable
ϡ
.BR capability (7)
륱ѥӥƥΥӥåȥޥǤ롣
.I CAP_*
ϥӥåֹɽǥåͤǤꡢ
ӥåȥեɤ OR Ԥ
.I CAP_*
ͤʬӥåȥեȤԤɬפ롣
typedef ϥݥ󥿤ʤΤǡ
ΥƥॳϤ¤Τˤϡ
.I struct __user_cap_header_struct

.I struct __user_cap_data_struct
Ȥ̾ѤʤФʤʤ

ͥ 2.6.25 ǤϡС
.B _LINUX_CAPABILITY_VERSION_1
 32 ӥåȥѥӥƥ侩Ǥ롣
ͥ 2.6.25 ʹߤǤϡС
.B _LINUX_CAPABILITY_VERSION_2
 64 ӥåȥѥӥƥ侩Ǥ롣
64 ӥåȥѥӥƥǤ
.IR datap [0]

.IR datap [1]
ѤΤФ
32 ӥåȥѥӥƥǤ
.IR datap [0]
Ѥ롣
.sp
Υƥॳεư˱ƶ⤦Ĥѹϡ
ե륱ѥӥƥ (file capabilities) Υͥˤ륵ݡ
(VFS ѥӥƥΥݡ) Ǥ롣
VFS ѥӥƥΥݡȤϸߤΤȤѥΥץǤ
(ͥ 2.6.24 ɲä줿)
.sp
.BR capget ()
Ǥϡ
.I hdrp->pid
Υեͤ˥ѥӥƥΤꤿץΥץ ID 
ꤹ뤳ȤǡǤդΥץΥѥӥƥĴ٤뤳ȤǤ롣
.SS VFS ѥӥƥݡȤƤ
VFS ѥӥƥΥݡȤǤϡø¹ԥե˥ѥӥƥ
ɲä뤿Υե°᥽åɤ줿
øǥƳˤꡢץˤ̤ΥץΥѥӥƥ
Ʊꤹ뵡ǽΥͥˤ륵ݡȤѻߤ롣
ĤޤꡢVFS ݡȤǤϡ
.BR capset ()
ƤӽФݤ
.I hdrp->pid
ͤȤƵΤ 0 
.BR getpid (2)
֤ͤȤʤ (ɤͤǤǤ)
.SS VFS ѥӥƥݡȤƤʤ
ͥ뤬 VFS ѥӥƥ򥵥ݡȤƤʤ硢
.I hdrp

.I pid
եɤ 0 ʳǤС
.BR capset ()
оݤ
.I pid
ǻꤵ줿åɤΥѥӥƥˤʤ롣
.I pid
 0 ξϸƤӽФΥåɤΥѥӥƥоݤȤʤ롣
.I pid
󥰥륹åɡץ򻲾ȤƤ硢
.I pid
ϰȤƤץID ȤäƻǤ롣
ޥåɡץΤ륹åɤоݤˤϡ
.BR gettid (2)
֤åID Ѥƻꤹɬפ롣
ޤ
.BR capset ()
Ǥ \-1  \-1 꾮ͤꤹ뤳ȤǤ롣
\-1 ϸƤӽФ
.BR init (8)
ƤΥåɤоݤȤѹԤȤ
\-1 꾮ͤ ID  \-\fIpid\fP Υץ롼פ
оݤȤѹԤȤ̣롣

Υǡξܺ٤
.BR capabilities (7)
򻲾Ȥ뤳ȡ
.SH ֤
ˤ 0 ֤顼ξˤ \-1 ֤
.I errno
Ŭڤꤹ롣

.I hdrp
Υե
.I version
˥ݡȤƤʤͤꤵ줿硢
ƤӽФϥ顼
.B EINVAL
ǼԤ
.I version
˥ͥ侩
.B _LINUX_CAPABILITY_VERSION_?
ꤹ롣
Τ褦ˤơߤο侩ѥӥƥӥ󤬲
Ĵ٤뤳ȤǤ롣
.SH 顼
.TP
.B EFAULT
ʥꥢɥ쥹
.I hdrp
 NULL ǤäƤϤʤʤ
.I datap
 NULL ꤷƤ褤Τϡ桼ͥ뤬ݡȤƤ
侩ΥѥӥƥСȽꤷ褦ȤƤȤǤ롣
.TP
.B EINVAL
Τɤ줫̵Ǥ롣
.TP
.B EPERM
ֵĥѥӥƥåȡפ˥ѥӥƥɲä褦ȤƤ뤫
⤷ϡֵĥѥӥƥåȡפ˴ޤޤʤѥӥƥ
ּ¸ѥӥƥåȡפַѾǽѥӥƥåȡפ
åȤ褦ȤƤ롣
.TP
.B EPERM
ƤӽФʬʳΥåɤΥѥӥƥ
.BR capset ()
Ȥäƽ褦Ȥʬøʤä
VFS ѥӥƥ򥵥ݡȤƤ륫ͥǤϡ
Ĥ뤳ȤϷ褷Ƥʤ
VFS ѥӥƥ򥵥ݡȤƤʤͥǤϡ
.B CAP_SETPCAP
ѥӥƥɬפǤ롣
(С 2.6.11 Υͥˤϡ
Υѥӥƥʤåɤ
.I pid
եɤ 0 Ǥʤ (Ĥޤꡢ0 
.BR getpid (2)
֤) ꤷƼʬȤΥѥӥƥѹ褦Ȥˤ⡢
Υ顼ȯȤХä)
.TP
.B ESRCH
Τ褦ʥåɤ¸ߤʤ
.SH 
Υƥॳ Linux ȼǤ롣
.SH 
ѥӥƥꤷꤹ뵡ǽΤΰܿ
󥿡ե
.I libcap
饤֥ˤä󶡤롣
Υ饤֥ϰʲǤ:
.br
http://www.kernel.org/pub/linux/libs/security/linux-privs
.SH Ϣ
.BR clone (2),
.BR gettid (2),
.BR capabilities (7)