[mirror_ubuntu-zesty-kernel.git] / fs / nfsd / nfsfh.c

/*
 * linux/fs/nfsd/nfsfh.c
 *
 * NFS server file handle treatment.
 *
 * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
 * Portions Copyright (C) 1999 G. Allen Morris III <gam3@acm.org>
 * Extensive rewrite by Neil Brown <neilb@cse.unsw.edu.au> Southern-Spring 1999
 * ... and again Southern-Winter 2001 to support export_operations
 */

#include <linux/exportfs.h>

#include <linux/sunrpc/svcauth_gss.h>
#include "nfsd.h"
#include "vfs.h"
#include "auth.h"

#define NFSDDBG_FACILITY		NFSDDBG_FH


/*
 * our acceptability function.
 * if NOSUBTREECHECK, accept anything
 * if not, require that we can walk up to exp->ex_dentry
 * doing some checks on the 'x' bits
 */
static int nfsd_acceptable(void *expv, struct dentry *dentry)
{
	struct svc_export *exp = expv;
	int rv;
	struct dentry *tdentry;
	struct dentry *parent;

	if (exp->ex_flags & NFSEXP_NOSUBTREECHECK)
		return 1;

	tdentry = dget(dentry);
	while (tdentry != exp->ex_path.dentry && !IS_ROOT(tdentry)) {
		/* make sure parents give x permission to user */
		int err;
		parent = dget_parent(tdentry);
		err = inode_permission(parent->d_inode, MAY_EXEC);
		if (err < 0) {
			dput(parent);
			break;
		}
		dput(tdentry);
		tdentry = parent;
	}
	if (tdentry != exp->ex_path.dentry)
		dprintk("nfsd_acceptable failed at %p %s\n", tdentry, tdentry->d_name.name);
	rv = (tdentry == exp->ex_path.dentry);
	dput(tdentry);
	return rv;
}

/* Type check. The correct error return for type mismatches does not seem to be
 * generally agreed upon. SunOS seems to use EISDIR if file isn't S_IFREG; a
 * comment in the NFSv3 spec says this is incorrect (implementation notes for
 * the write call).
 */
static inline __be32
nfsd_mode_check(struct svc_rqst *rqstp, umode_t mode, int type)
{
	/* Type can be negative when creating hardlinks - not to a dir */
	if (type > 0 && (mode & S_IFMT) != type) {
		if (rqstp->rq_vers == 4 && (mode & S_IFMT) == S_IFLNK)
			return nfserr_symlink;
		else if (type == S_IFDIR)
			return nfserr_notdir;
		else if ((mode & S_IFMT) == S_IFDIR)
			return nfserr_isdir;
		else
			return nfserr_inval;
	}
	if (type < 0 && (mode & S_IFMT) == -type) {
		if (rqstp->rq_vers == 4 && (mode & S_IFMT) == S_IFLNK)
			return nfserr_symlink;
		else if (type == -S_IFDIR)
			return nfserr_isdir;
		else
			return nfserr_notdir;
	}
	return 0;
}

static __be32 nfsd_setuser_and_check_port(struct svc_rqst *rqstp,
					  struct svc_export *exp)
{
	int flags = nfsexp_flags(rqstp, exp);

	/* Check if the request originated from a secure port. */
	if (!rqstp->rq_secure && (flags & NFSEXP_INSECURE_PORT)) {
		RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]);
		dprintk(KERN_WARNING
		       "nfsd: request from insecure port %s!\n",
		       svc_print_addr(rqstp, buf, sizeof(buf)));
		return nfserr_perm;
	}

	/* Set user creds for this exportpoint */
	return nfserrno(nfsd_setuser(rqstp, exp));
}

/*
 * Use the given filehandle to look up the corresponding export and
 * dentry.  On success, the results are used to set fh_export and
 * fh_dentry.
 */
static __be32 nfsd_set_fh_dentry(struct svc_rqst *rqstp, struct svc_fh *fhp)
{
	struct knfsd_fh	*fh = &fhp->fh_handle;
	struct fid *fid = NULL, sfid;
	struct svc_export *exp;
	struct dentry *dentry;
	int fileid_type;
	int data_left = fh->fh_size/4;
	__be32 error;

	error = nfserr_stale;
	if (rqstp->rq_vers > 2)
		error = nfserr_badhandle;
	if (rqstp->rq_vers == 4 && fh->fh_size == 0)
		return nfserr_nofilehandle;

	if (fh->fh_version == 1) {
		int len;

		if (--data_left < 0)
			return error;
		if (fh->fh_auth_type != 0)
			return error;
		len = key_len(fh->fh_fsid_type) / 4;
		if (len == 0)
			return error;
		if  (fh->fh_fsid_type == FSID_MAJOR_MINOR) {
			/* deprecated, convert to type 3 */
			len = key_len(FSID_ENCODE_DEV)/4;
			fh->fh_fsid_type = FSID_ENCODE_DEV;
			fh->fh_fsid[0] = new_encode_dev(MKDEV(ntohl(fh->fh_fsid[0]), ntohl(fh->fh_fsid[1])));
			fh->fh_fsid[1] = fh->fh_fsid[2];
		}
		data_left -= len;
		if (data_left < 0)
			return error;
		exp = rqst_exp_find(rqstp, fh->fh_fsid_type, fh->fh_auth);
		fid = (struct fid *)(fh->fh_auth + len);
	} else {
		__u32 tfh[2];
		dev_t xdev;
		ino_t xino;

		if (fh->fh_size != NFS_FHSIZE)
			return error;
		/* assume old filehandle format */
		xdev = old_decode_dev(fh->ofh_xdev);
		xino = u32_to_ino_t(fh->ofh_xino);
		mk_fsid(FSID_DEV, tfh, xdev, xino, 0, NULL);
		exp = rqst_exp_find(rqstp, FSID_DEV, tfh);
	}

	error = nfserr_stale;
	if (PTR_ERR(exp) == -ENOENT)
		return error;

	if (IS_ERR(exp))
		return nfserrno(PTR_ERR(exp));

	if (exp->ex_flags & NFSEXP_NOSUBTREECHECK) {
		/* Elevate privileges so that the lack of 'r' or 'x'
		 * permission on some parent directory will
		 * not stop exportfs_decode_fh from being able
		 * to reconnect a directory into the dentry cache.
		 * The same problem can affect "SUBTREECHECK" exports,
		 * but as nfsd_acceptable depends on correct
		 * access control settings being in effect, we cannot
		 * fix that case easily.
		 */
		struct cred *new = prepare_creds();
		if (!new)
			return nfserrno(-ENOMEM);
		new->cap_effective =
			cap_raise_nfsd_set(new->cap_effective,
					   new->cap_permitted);
		put_cred(override_creds(new));
		put_cred(new);
	} else {
		error = nfsd_setuser_and_check_port(rqstp, exp);
		if (error)
			goto out;
	}

	/*
	 * Look up the dentry using the NFS file handle.
	 */
	error = nfserr_stale;
	if (rqstp->rq_vers > 2)
		error = nfserr_badhandle;

	if (fh->fh_version != 1) {
		sfid.i32.ino = fh->ofh_ino;
		sfid.i32.gen = fh->ofh_generation;
		sfid.i32.parent_ino = fh->ofh_dirino;
		fid = &sfid;
		data_left = 3;
		if (fh->ofh_dirino == 0)
			fileid_type = FILEID_INO32_GEN;
		else
			fileid_type = FILEID_INO32_GEN_PARENT;
	} else
		fileid_type = fh->fh_fileid_type;

	if (fileid_type == FILEID_ROOT)
		dentry = dget(exp->ex_path.dentry);
	else {
		dentry = exportfs_decode_fh(exp->ex_path.mnt, fid,
				data_left, fileid_type,
				nfsd_acceptable, exp);
	}
	if (dentry == NULL)
		goto out;
	if (IS_ERR(dentry)) {
		if (PTR_ERR(dentry) != -EINVAL)
			error = nfserrno(PTR_ERR(dentry));
		goto out;
	}

	if (S_ISDIR(dentry->d_inode->i_mode) &&
			(dentry->d_flags & DCACHE_DISCONNECTED)) {
		printk("nfsd: find_fh_dentry returned a DISCONNECTED directory: %s/%s\n",
				dentry->d_parent->d_name.name, dentry->d_name.name);
	}

	fhp->fh_dentry = dentry;
	fhp->fh_export = exp;
	return 0;
out:
	exp_put(exp);
	return error;
}

/**
 * fh_verify - filehandle lookup and access checking
 * @rqstp: pointer to current rpc request
 * @fhp: filehandle to be verified
 * @type: expected type of object pointed to by filehandle
 * @access: type of access needed to object
 *
 * Look up a dentry from the on-the-wire filehandle, check the client's
 * access to the export, and set the current task's credentials.
 *
 * Regardless of success or failure of fh_verify(), fh_put() should be
 * called on @fhp when the caller is finished with the filehandle.
 *
 * fh_verify() may be called multiple times on a given filehandle, for
 * example, when processing an NFSv4 compound.  The first call will look
 * up a dentry using the on-the-wire filehandle.  Subsequent calls will
 * skip the lookup and just perform the other checks and possibly change
 * the current task's credentials.
 *
 * @type specifies the type of object expected using one of the S_IF*
 * constants defined in include/linux/stat.h.  The caller may use zero
 * to indicate that it doesn't care, or a negative integer to indicate
 * that it expects something not of the given type.
 *
 * @access is formed from the NFSD_MAY_* constants defined in
 * include/linux/nfsd/nfsd.h.
 */
__be32
fh_verify(struct svc_rqst *rqstp, struct svc_fh *fhp, int type, int access)
{
	struct svc_export *exp;
	struct dentry	*dentry;
	__be32		error;

	dprintk("nfsd: fh_verify(%s)\n", SVCFH_fmt(fhp));

	if (!fhp->fh_dentry) {
		error = nfsd_set_fh_dentry(rqstp, fhp);
		if (error)
			goto out;
	}
	dentry = fhp->fh_dentry;
	exp = fhp->fh_export;
	/*
	 * We still have to do all these permission checks, even when
	 * fh_dentry is already set:
	 * 	- fh_verify may be called multiple times with different
	 * 	  "access" arguments (e.g. nfsd_proc_create calls
	 * 	  fh_verify(...,NFSD_MAY_EXEC) first, then later (in
	 * 	  nfsd_create) calls fh_verify(...,NFSD_MAY_CREATE).
	 *	- in the NFSv4 case, the filehandle may have been filled
	 *	  in by fh_compose, and given a dentry, but further
	 *	  compound operations performed with that filehandle
	 *	  still need permissions checks.  In the worst case, a
	 *	  mountpoint crossing may have changed the export
	 *	  options, and we may now need to use a different uid
	 *	  (for example, if different id-squashing options are in
	 *	  effect on the new filesystem).
	 */
	error = nfsd_setuser_and_check_port(rqstp, exp);
	if (error)
		goto out;

	error = nfsd_mode_check(rqstp, dentry->d_inode->i_mode, type);
	if (error)
		goto out;

	/*
	 * pseudoflavor restrictions are not enforced on NLM,
	 * which clients virtually always use auth_sys for,
	 * even while using RPCSEC_GSS for NFS.
	 */
	if (access & NFSD_MAY_LOCK)
		goto skip_pseudoflavor_check;
	/*
	 * Clients may expect to be able to use auth_sys during mount,
	 * even if they use gss for everything else; see section 2.3.2
	 * of rfc 2623.
	 */
	if (access & NFSD_MAY_BYPASS_GSS_ON_ROOT
			&& exp->ex_path.dentry == dentry)
		goto skip_pseudoflavor_check;

	error = check_nfsd_access(exp, rqstp);
	if (error)
		goto out;

skip_pseudoflavor_check:
	/* Finally, check access permissions. */
	error = nfsd_permission(rqstp, exp, dentry, access);

	if (error) {
		dprintk("fh_verify: %s/%s permission failure, "
			"acc=%x, error=%d\n",
			dentry->d_parent->d_name.name,
			dentry->d_name.name,
			access, ntohl(error));
	}
out:
	if (error == nfserr_stale)
		nfsdstats.fh_stale++;
	return error;
}


/*
 * Compose a file handle for an NFS reply.
 *
 * Note that when first composed, the dentry may not yet have
 * an inode.  In this case a call to fh_update should be made
 * before the fh goes out on the wire ...
 */
static void _fh_update(struct svc_fh *fhp, struct svc_export *exp,
		struct dentry *dentry)
{
	if (dentry != exp->ex_path.dentry) {
		struct fid *fid = (struct fid *)
			(fhp->fh_handle.fh_auth + fhp->fh_handle.fh_size/4 - 1);
		int maxsize = (fhp->fh_maxsize - fhp->fh_handle.fh_size)/4;
		int subtreecheck = !(exp->ex_flags & NFSEXP_NOSUBTREECHECK);

		fhp->fh_handle.fh_fileid_type =
			exportfs_encode_fh(dentry, fid, &maxsize, subtreecheck);
		fhp->fh_handle.fh_size += maxsize * 4;
	} else {
		fhp->fh_handle.fh_fileid_type = FILEID_ROOT;
	}
}

/*
 * for composing old style file handles
 */
static inline void _fh_update_old(struct dentry *dentry,
				  struct svc_export *exp,
				  struct knfsd_fh *fh)
{
	fh->ofh_ino = ino_t_to_u32(dentry->d_inode->i_ino);
	fh->ofh_generation = dentry->d_inode->i_generation;
	if (S_ISDIR(dentry->d_inode->i_mode) ||
	    (exp->ex_flags & NFSEXP_NOSUBTREECHECK))
		fh->ofh_dirino = 0;
}

static bool is_root_export(struct svc_export *exp)
{
	return exp->ex_path.dentry == exp->ex_path.dentry->d_sb->s_root;
}

static struct super_block *exp_sb(struct svc_export *exp)
{
	return exp->ex_path.dentry->d_inode->i_sb;
}

static bool fsid_type_ok_for_exp(u8 fsid_type, struct svc_export *exp)
{
	switch (fsid_type) {
	case FSID_DEV:
		if (!old_valid_dev(exp_sb(exp)->s_dev))
			return 0;
		/* FALL THROUGH */
	case FSID_MAJOR_MINOR:
	case FSID_ENCODE_DEV:
		return exp_sb(exp)->s_type->fs_flags & FS_REQUIRES_DEV;
	case FSID_NUM:
		return exp->ex_flags & NFSEXP_FSID;
	case FSID_UUID8:
	case FSID_UUID16:
		if (!is_root_export(exp))
			return 0;
		/* fall through */
	case FSID_UUID4_INUM:
	case FSID_UUID16_INUM:
		return exp->ex_uuid != NULL;
	}
	return 1;
}


static void set_version_and_fsid_type(struct svc_fh *fhp, struct svc_export *exp, struct svc_fh *ref_fh)
{
	u8 version;
	u8 fsid_type;
retry:
	version = 1;
	if (ref_fh && ref_fh->fh_export == exp) {
		version = ref_fh->fh_handle.fh_version;
		fsid_type = ref_fh->fh_handle.fh_fsid_type;

		ref_fh = NULL;

		switch (version) {
		case 0xca:
			fsid_type = FSID_DEV;
			break;
		case 1:
			break;
		default:
			goto retry;
		}

		/*
		 * As the fsid -> filesystem mapping was guided by
		 * user-space, there is no guarantee that the filesystem
		 * actually supports that fsid type. If it doesn't we
		 * loop around again without ref_fh set.
		 */
		if (!fsid_type_ok_for_exp(fsid_type, exp))
			goto retry;
	} else if (exp->ex_flags & NFSEXP_FSID) {
		fsid_type = FSID_NUM;
	} else if (exp->ex_uuid) {
		if (fhp->fh_maxsize >= 64) {
			if (is_root_export(exp))
				fsid_type = FSID_UUID16;
			else
				fsid_type = FSID_UUID16_INUM;
		} else {
			if (is_root_export(exp))
				fsid_type = FSID_UUID8;
			else
				fsid_type = FSID_UUID4_INUM;
		}
	} else if (!old_valid_dev(exp_sb(exp)->s_dev))
		/* for newer device numbers, we must use a newer fsid format */
		fsid_type = FSID_ENCODE_DEV;
	else
		fsid_type = FSID_DEV;
	fhp->fh_handle.fh_version = version;
	if (version)
		fhp->fh_handle.fh_fsid_type = fsid_type;
}

__be32
fh_compose(struct svc_fh *fhp, struct svc_export *exp, struct dentry *dentry,
	   struct svc_fh *ref_fh)
{
	/* ref_fh is a reference file handle.
	 * if it is non-null and for the same filesystem, then we should compose
	 * a filehandle which is of the same version, where possible.
	 * Currently, that means that if ref_fh->fh_handle.fh_version == 0xca
	 * Then create a 32byte filehandle using nfs_fhbase_old
	 *
	 */

	struct inode * inode = dentry->d_inode;
	struct dentry *parent = dentry->d_parent;
	__u32 *datap;
	dev_t ex_dev = exp_sb(exp)->s_dev;

	dprintk("nfsd: fh_compose(exp %02x:%02x/%ld %s/%s, ino=%ld)\n",
		MAJOR(ex_dev), MINOR(ex_dev),
		(long) exp->ex_path.dentry->d_inode->i_ino,
		parent->d_name.name, dentry->d_name.name,
		(inode ? inode->i_ino : 0));

	/* Choose filehandle version and fsid type based on
	 * the reference filehandle (if it is in the same export)
	 * or the export options.
	 */
	 set_version_and_fsid_type(fhp, exp, ref_fh);

	if (ref_fh == fhp)
		fh_put(ref_fh);

	if (fhp->fh_locked || fhp->fh_dentry) {
		printk(KERN_ERR "fh_compose: fh %s/%s not initialized!\n",
		       parent->d_name.name, dentry->d_name.name);
	}
	if (fhp->fh_maxsize < NFS_FHSIZE)
		printk(KERN_ERR "fh_compose: called with maxsize %d! %s/%s\n",
		       fhp->fh_maxsize,
		       parent->d_name.name, dentry->d_name.name);

	fhp->fh_dentry = dget(dentry); /* our internal copy */
	fhp->fh_export = exp;
	cache_get(&exp->h);

	if (fhp->fh_handle.fh_version == 0xca) {
		/* old style filehandle please */
		memset(&fhp->fh_handle.fh_base, 0, NFS_FHSIZE);
		fhp->fh_handle.fh_size = NFS_FHSIZE;
		fhp->fh_handle.ofh_dcookie = 0xfeebbaca;
		fhp->fh_handle.ofh_dev =  old_encode_dev(ex_dev);
		fhp->fh_handle.ofh_xdev = fhp->fh_handle.ofh_dev;
		fhp->fh_handle.ofh_xino =
			ino_t_to_u32(exp->ex_path.dentry->d_inode->i_ino);
		fhp->fh_handle.ofh_dirino = ino_t_to_u32(parent_ino(dentry));
		if (inode)
			_fh_update_old(dentry, exp, &fhp->fh_handle);
	} else {
		int len;
		fhp->fh_handle.fh_auth_type = 0;
		datap = fhp->fh_handle.fh_auth+0;
		mk_fsid(fhp->fh_handle.fh_fsid_type, datap, ex_dev,
			exp->ex_path.dentry->d_inode->i_ino,
			exp->ex_fsid, exp->ex_uuid);

		len = key_len(fhp->fh_handle.fh_fsid_type);
		datap += len/4;
		fhp->fh_handle.fh_size = 4 + len;

		if (inode)
			_fh_update(fhp, exp, dentry);
		if (fhp->fh_handle.fh_fileid_type == 255) {
			fh_put(fhp);
			return nfserr_opnotsupp;
		}
	}

	return 0;
}

/*
 * Update file handle information after changing a dentry.
 * This is only called by nfsd_create, nfsd_create_v3 and nfsd_proc_create
 */
__be32
fh_update(struct svc_fh *fhp)
{
	struct dentry *dentry;

	if (!fhp->fh_dentry)
		goto out_bad;

	dentry = fhp->fh_dentry;
	if (!dentry->d_inode)
		goto out_negative;
	if (fhp->fh_handle.fh_version != 1) {
		_fh_update_old(dentry, fhp->fh_export, &fhp->fh_handle);
	} else {
		if (fhp->fh_handle.fh_fileid_type != FILEID_ROOT)
			goto out;

		_fh_update(fhp, fhp->fh_export, dentry);
		if (fhp->fh_handle.fh_fileid_type == 255)
			return nfserr_opnotsupp;
	}
out:
	return 0;

out_bad:
	printk(KERN_ERR "fh_update: fh not verified!\n");
	goto out;
out_negative:
	printk(KERN_ERR "fh_update: %s/%s still negative!\n",
		dentry->d_parent->d_name.name, dentry->d_name.name);
	goto out;
}

/*
 * Release a file handle.
 */
void
fh_put(struct svc_fh *fhp)
{
	struct dentry * dentry = fhp->fh_dentry;
	struct svc_export * exp = fhp->fh_export;
	if (dentry) {
		fh_unlock(fhp);
		fhp->fh_dentry = NULL;
		dput(dentry);
#ifdef CONFIG_NFSD_V3
		fhp->fh_pre_saved = 0;
		fhp->fh_post_saved = 0;
#endif
	}
	if (exp) {
		cache_put(&exp->h, &svc_export_cache);
		fhp->fh_export = NULL;
	}
	return;
}

/*
 * Shorthand for dprintk()'s
 */
char * SVCFH_fmt(struct svc_fh *fhp)
{
	struct knfsd_fh *fh = &fhp->fh_handle;

	static char buf[80];
	sprintf(buf, "%d: %08x %08x %08x %08x %08x %08x",
		fh->fh_size,
		fh->fh_base.fh_pad[0],
		fh->fh_base.fh_pad[1],
		fh->fh_base.fh_pad[2],
		fh->fh_base.fh_pad[3],
		fh->fh_base.fh_pad[4],
		fh->fh_base.fh_pad[5]);
	return buf;
}

enum fsid_source fsid_source(struct svc_fh *fhp)
{
	if (fhp->fh_handle.fh_version != 1)
		return FSIDSOURCE_DEV;
	switch(fhp->fh_handle.fh_fsid_type) {
	case FSID_DEV:
	case FSID_ENCODE_DEV:
	case FSID_MAJOR_MINOR:
		if (exp_sb(fhp->fh_export)->s_type->fs_flags & FS_REQUIRES_DEV)
			return FSIDSOURCE_DEV;
		break;
	case FSID_NUM:
		if (fhp->fh_export->ex_flags & NFSEXP_FSID)
			return FSIDSOURCE_FSID;
		break;
	default:
		break;
	}
	/* either a UUID type filehandle, or the filehandle doesn't
	 * match the export.
	 */
	if (fhp->fh_export->ex_flags & NFSEXP_FSID)
		return FSIDSOURCE_FSID;
	if (fhp->fh_export->ex_uuid)
		return FSIDSOURCE_UUID;
	return FSIDSOURCE_DEV;
}
Commit	Line	Data
1da177e4 LT	1	/*
	2	* linux/fs/nfsd/nfsfh.c
	3	*
	4	* NFS server file handle treatment.
	5	*
	6	* Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
	7	* Portions Copyright (C) 1999 G. Allen Morris III <gam3@acm.org>
	8	* Extensive rewrite by Neil Brown <neilb@cse.unsw.edu.au> Southern-Spring 1999
	9	* ... and again Southern-Winter 2001 to support export_operations
	10	*/
	11
a5694255	12	#include <linux/exportfs.h>
1da177e4	13
32c1eb0c	14	#include <linux/sunrpc/svcauth_gss.h>
9a74af21	15	#include "nfsd.h"
0a3adade	16	#include "vfs.h"
2e8138a2	17	#include "auth.h"
1da177e4 LT	18
1da177e4 LT	19	#define NFSDDBG_FACILITY NFSDDBG_FH
1da177e4 LT	20
1da177e4 LT	21
1da177e4 LT	22	/*
	23	* our acceptability function.
	24	* if NOSUBTREECHECK, accept anything
	25	* if not, require that we can walk up to exp->ex_dentry
	26	* doing some checks on the 'x' bits
	27	*/
	28	static int nfsd_acceptable(void expv, struct dentry dentry)
	29	{
	30	struct svc_export *exp = expv;
	31	int rv;
	32	struct dentry *tdentry;
	33	struct dentry *parent;
	34
	35	if (exp->ex_flags & NFSEXP_NOSUBTREECHECK)
	36	return 1;
	37
	38	tdentry = dget(dentry);
54775491	39	while (tdentry != exp->ex_path.dentry && !IS_ROOT(tdentry)) {
1da177e4 LT	40	/* make sure parents give x permission to user */
	41	int err;
	42	parent = dget_parent(tdentry);
f419a2e3	43	err = inode_permission(parent->d_inode, MAY_EXEC);
1da177e4 LT	44	if (err < 0) {
	45	dput(parent);
	46	break;
	47	}
	48	dput(tdentry);
	49	tdentry = parent;
	50	}
54775491	51	if (tdentry != exp->ex_path.dentry)
1da177e4	52	dprintk("nfsd_acceptable failed at %p %s\n", tdentry, tdentry->d_name.name);
54775491	53	rv = (tdentry == exp->ex_path.dentry);
1da177e4 LT	54	dput(tdentry);
	55	return rv;
	56	}
	57
	58	/* Type check. The correct error return for type mismatches does not seem to be
	59	* generally agreed upon. SunOS seems to use EISDIR if file isn't S_IFREG; a
	60	* comment in the NFSv3 spec says this is incorrect (implementation notes for
	61	* the write call).
	62	*/
83b11340	63	static inline __be32
1da177e4 LT	64	nfsd_mode_check(struct svc_rqst *rqstp, umode_t mode, int type)
	65	{
	66	/* Type can be negative when creating hardlinks - not to a dir */
	67	if (type > 0 && (mode & S_IFMT) != type) {
	68	if (rqstp->rq_vers == 4 && (mode & S_IFMT) == S_IFLNK)
	69	return nfserr_symlink;
	70	else if (type == S_IFDIR)
	71	return nfserr_notdir;
	72	else if ((mode & S_IFMT) == S_IFDIR)
	73	return nfserr_isdir;
	74	else
	75	return nfserr_inval;
	76	}
	77	if (type < 0 && (mode & S_IFMT) == -type) {
	78	if (rqstp->rq_vers == 4 && (mode & S_IFMT) == S_IFLNK)
	79	return nfserr_symlink;
	80	else if (type == -S_IFDIR)
	81	return nfserr_isdir;
	82	else
	83	return nfserr_notdir;
	84	}
	85	return 0;
	86	}
	87
6fa02839 BF	88	static __be32 nfsd_setuser_and_check_port(struct svc_rqst *rqstp,
	89	struct svc_export *exp)
	90	{
12045a6e BF	91	int flags = nfsexp_flags(rqstp, exp);
12045a6e BF	92
6fa02839	93	/* Check if the request originated from a secure port. */
12045a6e	94	if (!rqstp->rq_secure && (flags & NFSEXP_INSECURE_PORT)) {
5216a8e7	95	RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]);
6fa02839 BF	96	dprintk(KERN_WARNING
	97	"nfsd: request from insecure port %s!\n",
	98	svc_print_addr(rqstp, buf, sizeof(buf)));
	99	return nfserr_perm;
	100	}
	101
	102	/* Set user creds for this exportpoint */
	103	return nfserrno(nfsd_setuser(rqstp, exp));
	104	}
	105
03550fac BF	106	/*
	107	* Use the given filehandle to look up the corresponding export and
	108	* dentry. On success, the results are used to set fh_export and
	109	* fh_dentry.
	110	*/
	111	static __be32 nfsd_set_fh_dentry(struct svc_rqst rqstp, struct svc_fh fhp)
	112	{
	113	struct knfsd_fh *fh = &fhp->fh_handle;
	114	struct fid *fid = NULL, sfid;
	115	struct svc_export *exp;
	116	struct dentry *dentry;
	117	int fileid_type;
	118	int data_left = fh->fh_size/4;
	119	__be32 error;
	120
	121	error = nfserr_stale;
	122	if (rqstp->rq_vers > 2)
	123	error = nfserr_badhandle;
	124	if (rqstp->rq_vers == 4 && fh->fh_size == 0)
	125	return nfserr_nofilehandle;
	126
	127	if (fh->fh_version == 1) {
	128	int len;
	129
	130	if (--data_left < 0)
	131	return error;
	132	if (fh->fh_auth_type != 0)
	133	return error;
	134	len = key_len(fh->fh_fsid_type) / 4;
	135	if (len == 0)
	136	return error;
	137	if (fh->fh_fsid_type == FSID_MAJOR_MINOR) {
	138	/* deprecated, convert to type 3 */
	139	len = key_len(FSID_ENCODE_DEV)/4;
	140	fh->fh_fsid_type = FSID_ENCODE_DEV;
	141	fh->fh_fsid[0] = new_encode_dev(MKDEV(ntohl(fh->fh_fsid[0]), ntohl(fh->fh_fsid[1])));
	142	fh->fh_fsid[1] = fh->fh_fsid[2];
	143	}
	144	data_left -= len;
	145	if (data_left < 0)
	146	return error;
	147	exp = rqst_exp_find(rqstp, fh->fh_fsid_type, fh->fh_auth);
	148	fid = (struct fid *)(fh->fh_auth + len);
	149	} else {
	150	__u32 tfh[2];
	151	dev_t xdev;
	152	ino_t xino;
	153
	154	if (fh->fh_size != NFS_FHSIZE)
	155	return error;
	156	/* assume old filehandle format */
	157	xdev = old_decode_dev(fh->ofh_xdev);
	158	xino = u32_to_ino_t(fh->ofh_xino);
	159	mk_fsid(FSID_DEV, tfh, xdev, xino, 0, NULL);
	160	exp = rqst_exp_find(rqstp, FSID_DEV, tfh);
	161	}
	162
	163	error = nfserr_stale;
	164	if (PTR_ERR(exp) == -ENOENT)
	165	return error;
	166
	167	if (IS_ERR(exp))
	168	return nfserrno(PTR_ERR(exp));
	169
496d6c32 NB	170	if (exp->ex_flags & NFSEXP_NOSUBTREECHECK) {
	171	/* Elevate privileges so that the lack of 'r' or 'x'
	172	* permission on some parent directory will
	173	* not stop exportfs_decode_fh from being able
	174	* to reconnect a directory into the dentry cache.
	175	* The same problem can affect "SUBTREECHECK" exports,
	176	* but as nfsd_acceptable depends on correct
	177	* access control settings being in effect, we cannot
	178	* fix that case easily.
	179	*/
d84f4f99 DH	180	struct cred *new = prepare_creds();
	181	if (!new)
	182	return nfserrno(-ENOMEM);
	183	new->cap_effective =
	184	cap_raise_nfsd_set(new->cap_effective,
	185	new->cap_permitted);
	186	put_cred(override_creds(new));
	187	put_cred(new);
496d6c32 NB	188	} else {
	189	error = nfsd_setuser_and_check_port(rqstp, exp);
	190	if (error)
	191	goto out;
	192	}
03550fac BF	193
	194	/*
	195	* Look up the dentry using the NFS file handle.
	196	*/
	197	error = nfserr_stale;
	198	if (rqstp->rq_vers > 2)
	199	error = nfserr_badhandle;
	200
	201	if (fh->fh_version != 1) {
	202	sfid.i32.ino = fh->ofh_ino;
	203	sfid.i32.gen = fh->ofh_generation;
	204	sfid.i32.parent_ino = fh->ofh_dirino;
	205	fid = &sfid;
	206	data_left = 3;
	207	if (fh->ofh_dirino == 0)
	208	fileid_type = FILEID_INO32_GEN;
	209	else
	210	fileid_type = FILEID_INO32_GEN_PARENT;
	211	} else
	212	fileid_type = fh->fh_fileid_type;
	213
	214	if (fileid_type == FILEID_ROOT)
	215	dentry = dget(exp->ex_path.dentry);
	216	else {
	217	dentry = exportfs_decode_fh(exp->ex_path.mnt, fid,
	218	data_left, fileid_type,
	219	nfsd_acceptable, exp);
	220	}
	221	if (dentry == NULL)
	222	goto out;
	223	if (IS_ERR(dentry)) {
	224	if (PTR_ERR(dentry) != -EINVAL)
	225	error = nfserrno(PTR_ERR(dentry));
	226	goto out;
	227	}
	228
	229	if (S_ISDIR(dentry->d_inode->i_mode) &&
	230	(dentry->d_flags & DCACHE_DISCONNECTED)) {
	231	printk("nfsd: find_fh_dentry returned a DISCONNECTED directory: %s/%s\n",
	232	dentry->d_parent->d_name.name, dentry->d_name.name);
	233	}
	234
	235	fhp->fh_dentry = dentry;
	236	fhp->fh_export = exp;
03550fac BF	237	return 0;
	238	out:
	239	exp_put(exp);
	240	return error;
	241	}
	242
b3d47676 BF	243	/**
	244	* fh_verify - filehandle lookup and access checking
	245	* @rqstp: pointer to current rpc request
	246	* @fhp: filehandle to be verified
	247	* @type: expected type of object pointed to by filehandle
	248	* @access: type of access needed to object
	249	*
	250	* Look up a dentry from the on-the-wire filehandle, check the client's
	251	* access to the export, and set the current task's credentials.
	252	*
	253	* Regardless of success or failure of fh_verify(), fh_put() should be
	254	* called on @fhp when the caller is finished with the filehandle.
	255	*
	256	* fh_verify() may be called multiple times on a given filehandle, for
	257	* example, when processing an NFSv4 compound. The first call will look
	258	* up a dentry using the on-the-wire filehandle. Subsequent calls will
	259	* skip the lookup and just perform the other checks and possibly change
	260	* the current task's credentials.
1da177e4	261	*
b3d47676 BF	262	* @type specifies the type of object expected using one of the S_IF*
	263	* constants defined in include/linux/stat.h. The caller may use zero
	264	* to indicate that it doesn't care, or a negative integer to indicate
	265	* that it expects something not of the given type.
1da177e4	266	*
b3d47676 BF	267	* @access is formed from the NFSD_MAY_* constants defined in
b3d47676 BF	268	* include/linux/nfsd/nfsd.h.
1da177e4	269	*/
83b11340	270	__be32
1da177e4 LT	271	fh_verify(struct svc_rqst rqstp, struct svc_fh fhp, int type, int access)
1da177e4 LT	272	{
03550fac	273	struct svc_export *exp;
1da177e4	274	struct dentry *dentry;
03550fac	275	__be32 error;
1da177e4 LT	276
	277	dprintk("nfsd: fh_verify(%s)\n", SVCFH_fmt(fhp));
	278
1da177e4	279	if (!fhp->fh_dentry) {
03550fac	280	error = nfsd_set_fh_dentry(rqstp, fhp);
d1bbf14f N	281	if (error)
d1bbf14f N	282	goto out;
1da177e4	283	}
864f0f61 BF	284	dentry = fhp->fh_dentry;
	285	exp = fhp->fh_export;
	286	/*
	287	* We still have to do all these permission checks, even when
	288	* fh_dentry is already set:
	289	* - fh_verify may be called multiple times with different
	290	* "access" arguments (e.g. nfsd_proc_create calls
	291	* fh_verify(...,NFSD_MAY_EXEC) first, then later (in
	292	* nfsd_create) calls fh_verify(...,NFSD_MAY_CREATE).
	293	* - in the NFSv4 case, the filehandle may have been filled
	294	* in by fh_compose, and given a dentry, but further
	295	* compound operations performed with that filehandle
	296	* still need permissions checks. In the worst case, a
	297	* mountpoint crossing may have changed the export
	298	* options, and we may now need to use a different uid
	299	* (for example, if different id-squashing options are in
	300	* effect on the new filesystem).
	301	*/
	302	error = nfsd_setuser_and_check_port(rqstp, exp);
	303	if (error)
	304	goto out;
7fc90ec9	305
1da177e4 LT	306	error = nfsd_mode_check(rqstp, dentry->d_inode->i_mode, type);
	307	if (error)
	308	goto out;
	309
04716e66 BF	310	/*
	311	* pseudoflavor restrictions are not enforced on NLM,
	312	* which clients virtually always use auth_sys for,
	313	* even while using RPCSEC_GSS for NFS.
	314	*/
	315	if (access & NFSD_MAY_LOCK)
	316	goto skip_pseudoflavor_check;
	317	/*
	318	* Clients may expect to be able to use auth_sys during mount,
	319	* even if they use gss for everything else; see section 2.3.2
	320	* of rfc 2623.
	321	*/
	322	if (access & NFSD_MAY_BYPASS_GSS_ON_ROOT
	323	&& exp->ex_path.dentry == dentry)
	324	goto skip_pseudoflavor_check;
	325
	326	error = check_nfsd_access(exp, rqstp);
	327	if (error)
	328	goto out;
32c1eb0c	329
04716e66	330	skip_pseudoflavor_check:
1da177e4	331	/* Finally, check access permissions. */
0ec757df	332	error = nfsd_permission(rqstp, exp, dentry, access);
1da177e4	333
1da177e4	334	if (error) {
34e9a63b N	335	dprintk("fh_verify: %s/%s permission failure, "
	336	"acc=%x, error=%d\n",
	337	dentry->d_parent->d_name.name,
	338	dentry->d_name.name,
fc2dd2e5	339	access, ntohl(error));
1da177e4	340	}
1da177e4	341	out:
1da177e4 LT	342	if (error == nfserr_stale)
	343	nfsdstats.fh_stale++;
	344	return error;
	345	}
	346
	347
	348	/*
	349	* Compose a file handle for an NFS reply.
	350	*
	351	* Note that when first composed, the dentry may not yet have
	352	* an inode. In this case a call to fh_update should be made
	353	* before the fh goes out on the wire ...
	354	*/
6e91ea2b CH	355	static void _fh_update(struct svc_fh fhp, struct svc_export exp,
6e91ea2b CH	356	struct dentry *dentry)
1da177e4	357	{
54775491	358	if (dentry != exp->ex_path.dentry) {
6e91ea2b CH	359	struct fid fid = (struct fid )
	360	(fhp->fh_handle.fh_auth + fhp->fh_handle.fh_size/4 - 1);
	361	int maxsize = (fhp->fh_maxsize - fhp->fh_handle.fh_size)/4;
	362	int subtreecheck = !(exp->ex_flags & NFSEXP_NOSUBTREECHECK);
1da177e4	363
6e91ea2b CH	364	fhp->fh_handle.fh_fileid_type =
	365	exportfs_encode_fh(dentry, fid, &maxsize, subtreecheck);
	366	fhp->fh_handle.fh_size += maxsize * 4;
	367	} else {
	368	fhp->fh_handle.fh_fileid_type = FILEID_ROOT;
	369	}
1da177e4 LT	370	}
	371
	372	/*
	373	* for composing old style file handles
	374	*/
	375	static inline void _fh_update_old(struct dentry *dentry,
	376	struct svc_export *exp,
	377	struct knfsd_fh *fh)
	378	{
	379	fh->ofh_ino = ino_t_to_u32(dentry->d_inode->i_ino);
	380	fh->ofh_generation = dentry->d_inode->i_generation;
	381	if (S_ISDIR(dentry->d_inode->i_mode) \|\|
	382	(exp->ex_flags & NFSEXP_NOSUBTREECHECK))
	383	fh->ofh_dirino = 0;
	384	}
	385
8e498751 BF	386	static bool is_root_export(struct svc_export *exp)
	387	{
	388	return exp->ex_path.dentry == exp->ex_path.dentry->d_sb->s_root;
	389	}
	390
	391	static struct super_block exp_sb(struct svc_export exp)
	392	{
	393	return exp->ex_path.dentry->d_inode->i_sb;
	394	}
	395
	396	static bool fsid_type_ok_for_exp(u8 fsid_type, struct svc_export *exp)
	397	{
	398	switch (fsid_type) {
	399	case FSID_DEV:
	400	if (!old_valid_dev(exp_sb(exp)->s_dev))
	401	return 0;
	402	/* FALL THROUGH */
	403	case FSID_MAJOR_MINOR:
	404	case FSID_ENCODE_DEV:
	405	return exp_sb(exp)->s_type->fs_flags & FS_REQUIRES_DEV;
	406	case FSID_NUM:
	407	return exp->ex_flags & NFSEXP_FSID;
	408	case FSID_UUID8:
	409	case FSID_UUID16:
	410	if (!is_root_export(exp))
	411	return 0;
	412	/* fall through */
	413	case FSID_UUID4_INUM:
	414	case FSID_UUID16_INUM:
	415	return exp->ex_uuid != NULL;
	416	}
	417	return 1;
	418	}
	419
1da177e4	420
bc6c53d5 BF	421	static void set_version_and_fsid_type(struct svc_fh fhp, struct svc_export exp, struct svc_fh *ref_fh)
bc6c53d5 BF	422	{
b41eeef1	423	u8 version;
bc6c53d5 BF	424	u8 fsid_type;
bc6c53d5 BF	425	retry:
b41eeef1	426	version = 1;
7e405364	427	if (ref_fh && ref_fh->fh_export == exp) {
982aedfd	428	version = ref_fh->fh_handle.fh_version;
b41eeef1 N	429	fsid_type = ref_fh->fh_handle.fh_fsid_type;
b41eeef1 N	430
b41eeef1 N	431	ref_fh = NULL;
	432
	433	switch (version) {
	434	case 0xca:
af6a4e28	435	fsid_type = FSID_DEV;
b41eeef1 N	436	break;
	437	case 1:
	438	break;
	439	default:
	440	goto retry;
	441	}
	442
8e498751 BF	443	/*
	444	* As the fsid -> filesystem mapping was guided by
	445	* user-space, there is no guarantee that the filesystem
	446	* actually supports that fsid type. If it doesn't we
	447	* loop around again without ref_fh set.
982aedfd	448	*/
8e498751 BF	449	if (!fsid_type_ok_for_exp(fsid_type, exp))
8e498751 BF	450	goto retry;
30fa8c01 SD	451	} else if (exp->ex_flags & NFSEXP_FSID) {
30fa8c01 SD	452	fsid_type = FSID_NUM;
af6a4e28 N	453	} else if (exp->ex_uuid) {
af6a4e28 N	454	if (fhp->fh_maxsize >= 64) {
8e498751	455	if (is_root_export(exp))
af6a4e28 N	456	fsid_type = FSID_UUID16;
	457	else
	458	fsid_type = FSID_UUID16_INUM;
	459	} else {
8e498751	460	if (is_root_export(exp))
af6a4e28 N	461	fsid_type = FSID_UUID8;
	462	else
	463	fsid_type = FSID_UUID4_INUM;
	464	}
bc6c53d5	465	} else if (!old_valid_dev(exp_sb(exp)->s_dev))
1da177e4	466	/* for newer device numbers, we must use a newer fsid format */
af6a4e28	467	fsid_type = FSID_ENCODE_DEV;
982aedfd	468	else
af6a4e28	469	fsid_type = FSID_DEV;
bc6c53d5 BF	470	fhp->fh_handle.fh_version = version;
	471	if (version)
	472	fhp->fh_handle.fh_fsid_type = fsid_type;
	473	}
	474
	475	__be32
	476	fh_compose(struct svc_fh fhp, struct svc_export exp, struct dentry *dentry,
	477	struct svc_fh *ref_fh)
	478	{
	479	/* ref_fh is a reference file handle.
	480	* if it is non-null and for the same filesystem, then we should compose
	481	* a filehandle which is of the same version, where possible.
	482	* Currently, that means that if ref_fh->fh_handle.fh_version == 0xca
	483	* Then create a 32byte filehandle using nfs_fhbase_old
	484	*
	485	*/
	486
	487	struct inode * inode = dentry->d_inode;
	488	struct dentry *parent = dentry->d_parent;
	489	__u32 *datap;
	490	dev_t ex_dev = exp_sb(exp)->s_dev;
	491
	492	dprintk("nfsd: fh_compose(exp %02x:%02x/%ld %s/%s, ino=%ld)\n",
	493	MAJOR(ex_dev), MINOR(ex_dev),
	494	(long) exp->ex_path.dentry->d_inode->i_ino,
	495	parent->d_name.name, dentry->d_name.name,
	496	(inode ? inode->i_ino : 0));
	497
	498	/* Choose filehandle version and fsid type based on
	499	* the reference filehandle (if it is in the same export)
	500	* or the export options.
	501	*/
	502	set_version_and_fsid_type(fhp, exp, ref_fh);
1da177e4 LT	503
	504	if (ref_fh == fhp)
	505	fh_put(ref_fh);
	506
	507	if (fhp->fh_locked \|\| fhp->fh_dentry) {
	508	printk(KERN_ERR "fh_compose: fh %s/%s not initialized!\n",
982aedfd	509	parent->d_name.name, dentry->d_name.name);
1da177e4 LT	510	}
	511	if (fhp->fh_maxsize < NFS_FHSIZE)
	512	printk(KERN_ERR "fh_compose: called with maxsize %d! %s/%s\n",
982aedfd N	513	fhp->fh_maxsize,
982aedfd N	514	parent->d_name.name, dentry->d_name.name);
1da177e4 LT	515
	516	fhp->fh_dentry = dget(dentry); /* our internal copy */
	517	fhp->fh_export = exp;
	518	cache_get(&exp->h);
	519
bc6c53d5	520	if (fhp->fh_handle.fh_version == 0xca) {
1da177e4 LT	521	/* old style filehandle please */
	522	memset(&fhp->fh_handle.fh_base, 0, NFS_FHSIZE);
	523	fhp->fh_handle.fh_size = NFS_FHSIZE;
	524	fhp->fh_handle.ofh_dcookie = 0xfeebbaca;
	525	fhp->fh_handle.ofh_dev = old_encode_dev(ex_dev);
	526	fhp->fh_handle.ofh_xdev = fhp->fh_handle.ofh_dev;
982aedfd	527	fhp->fh_handle.ofh_xino =
54775491	528	ino_t_to_u32(exp->ex_path.dentry->d_inode->i_ino);
1da177e4 LT	529	fhp->fh_handle.ofh_dirino = ino_t_to_u32(parent_ino(dentry));
	530	if (inode)
	531	_fh_update_old(dentry, exp, &fhp->fh_handle);
	532	} else {
	533	int len;
1da177e4 LT	534	fhp->fh_handle.fh_auth_type = 0;
1da177e4 LT	535	datap = fhp->fh_handle.fh_auth+0;
bc6c53d5	536	mk_fsid(fhp->fh_handle.fh_fsid_type, datap, ex_dev,
54775491	537	exp->ex_path.dentry->d_inode->i_ino,
af6a4e28 N	538	exp->ex_fsid, exp->ex_uuid);
af6a4e28 N	539
bc6c53d5	540	len = key_len(fhp->fh_handle.fh_fsid_type);
1da177e4 LT	541	datap += len/4;
	542	fhp->fh_handle.fh_size = 4 + len;
	543
6e91ea2b CH	544	if (inode)
6e91ea2b CH	545	_fh_update(fhp, exp, dentry);
1be10a88 BF	546	if (fhp->fh_handle.fh_fileid_type == 255) {
1be10a88 BF	547	fh_put(fhp);
1da177e4	548	return nfserr_opnotsupp;
1be10a88	549	}
1da177e4 LT	550	}
1da177e4 LT	551
1da177e4 LT	552	return 0;
	553	}
	554
	555	/*
	556	* Update file handle information after changing a dentry.
	557	* This is only called by nfsd_create, nfsd_create_v3 and nfsd_proc_create
	558	*/
83b11340	559	__be32
1da177e4 LT	560	fh_update(struct svc_fh *fhp)
	561	{
	562	struct dentry *dentry;
982aedfd	563
1da177e4 LT	564	if (!fhp->fh_dentry)
	565	goto out_bad;
	566
	567	dentry = fhp->fh_dentry;
	568	if (!dentry->d_inode)
	569	goto out_negative;
	570	if (fhp->fh_handle.fh_version != 1) {
	571	_fh_update_old(dentry, fhp->fh_export, &fhp->fh_handle);
	572	} else {
6e91ea2b	573	if (fhp->fh_handle.fh_fileid_type != FILEID_ROOT)
4c9608b2	574	goto out;
6e91ea2b CH	575
6e91ea2b CH	576	_fh_update(fhp, fhp->fh_export, dentry);
1da177e4 LT	577	if (fhp->fh_handle.fh_fileid_type == 255)
	578	return nfserr_opnotsupp;
	579	}
	580	out:
	581	return 0;
	582
	583	out_bad:
	584	printk(KERN_ERR "fh_update: fh not verified!\n");
	585	goto out;
	586	out_negative:
	587	printk(KERN_ERR "fh_update: %s/%s still negative!\n",
	588	dentry->d_parent->d_name.name, dentry->d_name.name);
	589	goto out;
1da177e4 LT	590	}
	591
	592	/*
	593	* Release a file handle.
	594	*/
	595	void
	596	fh_put(struct svc_fh *fhp)
	597	{
	598	struct dentry * dentry = fhp->fh_dentry;
	599	struct svc_export * exp = fhp->fh_export;
	600	if (dentry) {
	601	fh_unlock(fhp);
	602	fhp->fh_dentry = NULL;
	603	dput(dentry);
	604	#ifdef CONFIG_NFSD_V3
	605	fhp->fh_pre_saved = 0;
	606	fhp->fh_post_saved = 0;
	607	#endif
1da177e4 LT	608	}
1da177e4 LT	609	if (exp) {
baab935f	610	cache_put(&exp->h, &svc_export_cache);
1da177e4 LT	611	fhp->fh_export = NULL;
	612	}
	613	return;
	614	}
	615
	616	/*
	617	* Shorthand for dprintk()'s
	618	*/
	619	char * SVCFH_fmt(struct svc_fh *fhp)
	620	{
	621	struct knfsd_fh *fh = &fhp->fh_handle;
	622
	623	static char buf[80];
	624	sprintf(buf, "%d: %08x %08x %08x %08x %08x %08x",
	625	fh->fh_size,
	626	fh->fh_base.fh_pad[0],
	627	fh->fh_base.fh_pad[1],
	628	fh->fh_base.fh_pad[2],
	629	fh->fh_base.fh_pad[3],
	630	fh->fh_base.fh_pad[4],
	631	fh->fh_base.fh_pad[5]);
	632	return buf;
	633	}
af6a4e28 N	634
	635	enum fsid_source fsid_source(struct svc_fh *fhp)
	636	{
	637	if (fhp->fh_handle.fh_version != 1)
	638	return FSIDSOURCE_DEV;
	639	switch(fhp->fh_handle.fh_fsid_type) {
	640	case FSID_DEV:
	641	case FSID_ENCODE_DEV:
	642	case FSID_MAJOR_MINOR:
8e498751	643	if (exp_sb(fhp->fh_export)->s_type->fs_flags & FS_REQUIRES_DEV)
b8da0d1c NB	644	return FSIDSOURCE_DEV;
b8da0d1c NB	645	break;
af6a4e28	646	case FSID_NUM:
af6a4e28 N	647	if (fhp->fh_export->ex_flags & NFSEXP_FSID)
af6a4e28 N	648	return FSIDSOURCE_FSID;
b8da0d1c NB	649	break;
	650	default:
	651	break;
af6a4e28	652	}
b8da0d1c NB	653	/* either a UUID type filehandle, or the filehandle doesn't
	654	* match the export.
	655	*/
	656	if (fhp->fh_export->ex_flags & NFSEXP_FSID)
	657	return FSIDSOURCE_FSID;
	658	if (fhp->fh_export->ex_uuid)
	659	return FSIDSOURCE_UUID;
	660	return FSIDSOURCE_DEV;
af6a4e28	661	}