linux_dsm_epyc7002/include/uapi/linux/nfsd/export.h
J. Bruce Fields 32ddd944a0 nfsd: opt in to labeled nfs per export
Currently turning on NFSv4.2 results in 4.2 clients suddenly seeing the
individual file labels as they're set on the server.  This is not what
they've previously seen, and not appropriate in may cases.  (In
particular, if clients have heterogenous security policies then one
client's labels may not even make sense to another.)  Labeled NFS should
be opted in only in those cases when the administrator knows it makes
sense.

It's helpful to be able to turn 4.2 on by default, and otherwise the
protocol upgrade seems free of regressions.  So, default labeled NFS to
off and provide an export flag to reenable it.

Users wanting labeled NFS support on an export will henceforth need to:

	- make sure 4.2 support is enabled on client and server (as
	  before), and
	- upgrade the server nfs-utils to a version supporting the new
	  "security_label" export flag.
	- set that "security_label" flag on the export.

This is commit may be seen as a regression to anyone currently depending
on security labels.  We believe those cases are currently rare.

Reported-by: tibbs@math.uh.edu
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2017-01-31 12:31:54 -05:00

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2.0 KiB
C

/*
* include/linux/nfsd/export.h
*
* Public declarations for NFS exports. The definitions for the
* syscall interface are in nfsctl.h
*
* Copyright (C) 1995-1997 Olaf Kirch <okir@monad.swb.de>
*/
#ifndef _UAPINFSD_EXPORT_H
#define _UAPINFSD_EXPORT_H
# include <linux/types.h>
/*
* Important limits for the exports stuff.
*/
#define NFSCLNT_IDMAX 1024
#define NFSCLNT_ADDRMAX 16
#define NFSCLNT_KEYMAX 32
/*
* Export flags.
*
* Please update the expflags[] array in fs/nfsd/export.c when adding
* a new flag.
*/
#define NFSEXP_READONLY 0x0001
#define NFSEXP_INSECURE_PORT 0x0002
#define NFSEXP_ROOTSQUASH 0x0004
#define NFSEXP_ALLSQUASH 0x0008
#define NFSEXP_ASYNC 0x0010
#define NFSEXP_GATHERED_WRITES 0x0020
#define NFSEXP_NOREADDIRPLUS 0x0040
#define NFSEXP_SECURITY_LABEL 0x0080
/* 0x100 currently unused */
#define NFSEXP_NOHIDE 0x0200
#define NFSEXP_NOSUBTREECHECK 0x0400
#define NFSEXP_NOAUTHNLM 0x0800 /* Don't authenticate NLM requests - just trust */
#define NFSEXP_MSNFS 0x1000 /* do silly things that MS clients expect; no longer supported */
#define NFSEXP_FSID 0x2000
#define NFSEXP_CROSSMOUNT 0x4000
#define NFSEXP_NOACL 0x8000 /* reserved for possible ACL related use */
/*
* The NFSEXP_V4ROOT flag causes the kernel to give access only to NFSv4
* clients, and only to the single directory that is the root of the
* export; further lookup and readdir operations are treated as if every
* subdirectory was a mountpoint, and ignored if they are not themselves
* exported. This is used by nfsd and mountd to construct the NFSv4
* pseudofilesystem, which provides access only to paths leading to each
* exported filesystem.
*/
#define NFSEXP_V4ROOT 0x10000
#define NFSEXP_PNFS 0x20000
/* All flags that we claim to support. (Note we don't support NOACL.) */
#define NFSEXP_ALLFLAGS 0x3FEFF
/* The flags that may vary depending on security flavor: */
#define NFSEXP_SECINFO_FLAGS (NFSEXP_READONLY | NFSEXP_ROOTSQUASH \
| NFSEXP_ALLSQUASH \
| NFSEXP_INSECURE_PORT)
#endif /* _UAPINFSD_EXPORT_H */