| ucred.9 (147647) | ucred.9 (183113) |
|---|---|
| 1.\" 2.\" Copyright (C) 2001 Chad David <davidc@acns.ab.ca>. All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice(s), this list of conditions and the following disclaimer as --- 10 unchanged lines hidden (view full) --- 19.\" DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 20.\" (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 21.\" SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 22.\" CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH 25.\" DAMAGE. 26.\" | 1.\" 2.\" Copyright (C) 2001 Chad David <davidc@acns.ab.ca>. All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice(s), this list of conditions and the following disclaimer as --- 10 unchanged lines hidden (view full) --- 19.\" DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 20.\" (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR 21.\" SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 22.\" CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH 25.\" DAMAGE. 26.\" |
| 27.\" $FreeBSD: head/share/man/man9/ucred.9 147647 2005-06-28 20:15:19Z hmp $ | 27.\" $FreeBSD: head/share/man/man9/ucred.9 183113 2008-09-17 15:49:44Z attilio $ |
| 28.\" 29.Dd March 3, 2002 30.Dt UCRED 9 31.Os 32.Sh NAME 33.Nm ucred , 34.Nm crget , 35.Nm crhold , --- 122 unchanged lines hidden (view full) --- 158.Pp 159In the common case, credentials required for access control decisions are 160used in a read-only manner. 161In these circumstances, the thread credential 162.Va td_ucred 163should be used, as it requires no locking to access safely, and remains stable 164for the duration of the call even in the face of a multi-threaded 165application changing the process credentials from another thread. | 28.\" 29.Dd March 3, 2002 30.Dt UCRED 9 31.Os 32.Sh NAME 33.Nm ucred , 34.Nm crget , 35.Nm crhold , --- 122 unchanged lines hidden (view full) --- 158.Pp 159In the common case, credentials required for access control decisions are 160used in a read-only manner. 161In these circumstances, the thread credential 162.Va td_ucred 163should be used, as it requires no locking to access safely, and remains stable 164for the duration of the call even in the face of a multi-threaded 165application changing the process credentials from another thread. |
| 166Primitives such as 167.Xr suser 9 168will assume the use of 169.Va td_ucred 170unless explicitly specified using 171.Xr suser_cred 9 . | |
| 172.Pp 173During a process credential update, the process lock must be held across 174check and update, to prevent race conditions. 175The process credential, 176.Va td->td_proc->p_ucred , 177must be used both for check and update. 178If a process credential is updated during a system call and checks against 179the thread credential are to be made later during the same system call, --- 31 unchanged lines hidden --- | 166.Pp 167During a process credential update, the process lock must be held across 168check and update, to prevent race conditions. 169The process credential, 170.Va td->td_proc->p_ucred , 171must be used both for check and update. 172If a process credential is updated during a system call and checks against 173the thread credential are to be made later during the same system call, --- 31 unchanged lines hidden --- |