1.\" $OpenBSD: nfssvc.2,v 1.21 2014/03/24 01:54:58 guenther Exp $ 2.\" $NetBSD: nfssvc.2,v 1.6 1995/02/27 12:35:08 cgd Exp $ 3.\" 4.\" Copyright (c) 1989, 1991, 1993 5.\" The Regents of the University of California. All rights reserved. 6.\" 7.\" Redistribution and use in source and binary forms, with or without 8.\" modification, are permitted provided that the following conditions 9.\" are met: 10.\" 1. Redistributions of source code must retain the above copyright 11.\" notice, this list of conditions and the following disclaimer. 12.\" 2. Redistributions in binary form must reproduce the above copyright 13.\" notice, this list of conditions and the following disclaimer in the 14.\" documentation and/or other materials provided with the distribution. 15.\" 3. Neither the name of the University nor the names of its contributors 16.\" may be used to endorse or promote products derived from this software 17.\" without specific prior written permission. 18.\" 19.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29.\" SUCH DAMAGE. 30.\" 31.\" @(#)nfssvc.2 8.1 (Berkeley) 6/9/93 32.\" 33.Dd $Mdocdate: March 24 2014 $ 34.Dt NFSSVC 2 35.Os 36.Sh NAME 37.Nm nfssvc 38.Nd NFS services 39.Sh SYNOPSIS 40.Fd #include <unistd.h> 41.Fd #include <nfs/nfs.h> 42.Ft int 43.Fn nfssvc "int flags" "void *argstructp" 44.Sh DESCRIPTION 45The 46.Fn nfssvc 47function is used by NFS daemons to pass information into the kernel 48and also to enter the kernel as a server daemon. 49The 50.Fa flags 51argument consists of several bits that show what action is to be taken 52once in the kernel and the 53.Fa argstructp 54points to one of two structures depending on which bits are set in 55flags. 56.Pp 57To enter an 58.Xr nfsd 8 59daemon into the kernel, 60.Fn nfssvc 61is called with the flag 62.Dv NFSSVC_NFSD 63and a pointer to a structure: 64.Bd -literal 65struct nfsd_srvargs { 66 struct nfsd *nsd_nfsd; /* Pointer to in kernel nfsd struct */ 67 uid_t nsd_uid; /* Effective uid mapped to cred */ 68 u_int32_t nsd_haddr; /* IP address of client */ 69 struct xucred nsd_cr; /* Cred. uid maps to */ 70 int nsd_authlen; /* Length of auth string (ret) */ 71 u_char *nsd_authstr; /* Auth string (ret) */ 72 int nsd_verflen; /* and the verifier */ 73 u_char *nsd_verfstr; 74 struct timeval nsd_timestamp; /* timestamp from verifier */ 75 u_int32_t nsd_ttl; /* credential ttl (sec) */ 76}; 77.Ed 78.Pp 79To add further sockets for processing by the 80.Xr nfsd 8 81server daemons the master 82.Xr nfsd 8 83daemon calls 84.Fn nfssvc 85with the flag 86.Dv NFSSVC_ADDSOCK 87and a pointer to a structure: 88.Bd -literal 89struct nfsd_args { 90 int sock; /* Socket to serve */ 91 caddr_t name; /* Client address for connection based sockets */ 92 int namelen; /* Length of name */ 93}; 94.Ed 95.Sh RETURN VALUES 96Normally 97.Nm nfssvc 98does not return unless the server 99is terminated by a signal when a value of 0 is returned. 100Otherwise, \-1 is returned and the global variable 101.Va errno 102is set to specify the error. 103.Sh ERRORS 104.Bl -tag -width Er 105.It Bq Er EPERM 106The caller is not the superuser. 107.It Bq Er EINVAL 108The flag argument consisted of incompatible or otherwise 109unsupported bits. 110.El 111.Sh SEE ALSO 112.Xr mount_nfs 8 , 113.Xr nfsd 8 , 114.Xr sysctl 8 115.Sh HISTORY 116The 117.Nm nfssvc 118function first appeared in 119.Bx 4.4 . 120.Sh BUGS 121The 122.Nm nfssvc 123system call is designed specifically for the 124.Tn NFS 125support daemons and as such is specific to their requirements. 126Several fields of the argument structures are assumed to be valid and 127sometimes to be unchanged from a previous call, such that 128.Fn nfssvc 129must be used with extreme care. 130