xref: /freebsd/share/man/man9/VFS_CHECKEXP.9 (revision 6f5b118fe160547f534f59705566fc02c126a2da)
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25.\" $FreeBSD$
26.\"
27.Dd June 16, 2020
28.Dt VFS_CHECKEXP 9
29.Os
30.Sh NAME
31.Nm VFS_CHECKEXP
32.Nd check if a file system is exported to a client
33.Sh SYNOPSIS
34.In sys/param.h
35.In sys/mount.h
36.Ft int
37.Fo VFS_CHECKEXP
38.Fa "struct mount *mp"
39.Fa "struct sockaddr *nam"
40.Fa "uint64_t *exflagsp"
41.Fa "struct ucred **credanonp"
42.Fa "int *numsecflavor"
43.Fa "int *secflavors"
44.Fc
45.Sh DESCRIPTION
46The
47.Fn VFS_CHECKEXP
48macro is used by the NFS server to check if a mount point is exported
49to a client.
50.Pp
51The arguments it expects are:
52.Bl -tag -width credanonp
53.It Fa mp
54The mount point to be checked.
55.It Fa nam
56An mbuf containing the network address of the client.
57.It Fa exflagsp
58Return parameter for the export flags for this client.
59.It Fa credanonp
60Return parameter for the anonymous credentials for this client.
61.It Fa numsecflavors
62Return value for the number of security flavors for this client.
63.It Fa secflavors
64Must be an array of size MAXSECFLAVORS, in which the security flavors
65for this client are returned.
66.El
67.Pp
68The
69.Fn VFS_CHECKEXP
70macro should be called on a file system's mount structure to determine if it
71is exported to a client whose address is contained in
72.Fa nam .
73.Pp
74It is generally called before
75.Xr VFS_FHTOVP 9
76to validate that a client has access to the file system.
77.Pp
78The file system should call
79.Xr vfs_export_lookup 9
80with the address of an appropriate
81.Vt netexport
82structure and the address of the client,
83.Fa nam ,
84to verify that the client can access this file system.
85.Sh RETURN VALUES
86The export flags, anonymous credentials and security flavors specific to the
87client (returned by
88.Xr vfs_export_lookup 9 )
89will be returned in
90.Fa *exflagsp ,
91.Fa *credanonp ,
92.Fa *numsecflavors
93and
94.Fa *secflavors .
95.Sh SEE ALSO
96.Xr VFS 9 ,
97.Xr VFS_FHTOVP 9 ,
98.Xr vnode 9 ,
99.Xr VOP_VPTOFH 9
100.Sh AUTHORS
101This manual page was written by
102.An Alfred Perlstein .
103