diff options
| author | glebius <glebius@FreeBSD.org> | 2012-09-12 09:50:17 +0000 |
|---|---|---|
| committer | glebius <glebius@FreeBSD.org> | 2012-09-12 09:50:17 +0000 |
| commit | 78d32fb722160149b58efdea9e1bf8865786ee9f (patch) | |
| tree | c85bc5c0fa292c47303a2499d61d7e7886b14cc8 /lib/libc/sys | |
| parent | 9428c312c85831539a93248f10813cf842ae1525 (diff) | |
| download | FreeBSD-src-78d32fb722160149b58efdea9e1bf8865786ee9f.zip FreeBSD-src-78d32fb722160149b58efdea9e1bf8865786ee9f.tar.gz | |
Describe in detail required conditions for receiving the SCM_CREDS
control message and suggest to use LOCAL_CREDS setsockopt() for
reliability.
Diffstat (limited to 'lib/libc/sys')
| -rw-r--r-- | lib/libc/sys/recv.2 | 22 |
1 files changed, 18 insertions, 4 deletions
diff --git a/lib/libc/sys/recv.2 b/lib/libc/sys/recv.2 index 66f311f..29ff747 100644 --- a/lib/libc/sys/recv.2 +++ b/lib/libc/sys/recv.2 @@ -28,7 +28,7 @@ .\" @(#)recv.2 8.3 (Berkeley) 2/21/94 .\" $FreeBSD$ .\" -.Dd December 28, 2006 +.Dd September 12, 2012 .Dt RECV 2 .Os .Sh NAME @@ -252,8 +252,21 @@ struct cmsgcred { }; .Ed .Pp -The kernel will fill in the credential information of the sending process -and deliver it to the receiver. +If a sender supplies ancillary data with enough space for the above struct +tagged as +.Dv SCM_CREDS +control message type to the +.Fn sendmsg +system call, then kernel will fill in the credential information of the +sending process and deliver it to the receiver. +Since receiver usually has no control over a sender, this method of retrieving +credential information isn't reliable. +For reliable retrieval of remote side credentials it is advised to use the +.Dv LOCAL_CREDS +socket option on the receiving socket. +See +.Xr unix 4 +for details. .Pp The .Fa msg_flags @@ -322,7 +335,8 @@ address space. .Xr getsockopt 2 , .Xr read 2 , .Xr select 2 , -.Xr socket 2 +.Xr socket 2 , +.Xr unix 4 .Sh HISTORY The .Fn recv |
