[linux-2.6-block.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)
{
	/* Check if the request originated from a secure port. */
	if (!rqstp->rq_secure && EX_SECURE(exp)) {
		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	{
	91	/* Check if the request originated from a secure port. */
	92	if (!rqstp->rq_secure && EX_SECURE(exp)) {
5216a8e7	93	RPC_IFDEBUG(char buf[RPC_MAX_ADDRBUFLEN]);
6fa02839 BF	94	dprintk(KERN_WARNING
	95	"nfsd: request from insecure port %s!\n",
	96	svc_print_addr(rqstp, buf, sizeof(buf)));
	97	return nfserr_perm;
	98	}
	99
	100	/* Set user creds for this exportpoint */
	101	return nfserrno(nfsd_setuser(rqstp, exp));
	102	}
	103
03550fac BF	104	/*
	105	* Use the given filehandle to look up the corresponding export and
	106	* dentry. On success, the results are used to set fh_export and
	107	* fh_dentry.
	108	*/
	109	static __be32 nfsd_set_fh_dentry(struct svc_rqst rqstp, struct svc_fh fhp)
	110	{
	111	struct knfsd_fh *fh = &fhp->fh_handle;
	112	struct fid *fid = NULL, sfid;
	113	struct svc_export *exp;
	114	struct dentry *dentry;
	115	int fileid_type;
	116	int data_left = fh->fh_size/4;
	117	__be32 error;
	118
	119	error = nfserr_stale;
	120	if (rqstp->rq_vers > 2)
	121	error = nfserr_badhandle;
	122	if (rqstp->rq_vers == 4 && fh->fh_size == 0)
	123	return nfserr_nofilehandle;
	124
	125	if (fh->fh_version == 1) {
	126	int len;
	127
	128	if (--data_left < 0)
	129	return error;
	130	if (fh->fh_auth_type != 0)
	131	return error;
	132	len = key_len(fh->fh_fsid_type) / 4;
	133	if (len == 0)
	134	return error;
	135	if (fh->fh_fsid_type == FSID_MAJOR_MINOR) {
	136	/* deprecated, convert to type 3 */
	137	len = key_len(FSID_ENCODE_DEV)/4;
	138	fh->fh_fsid_type = FSID_ENCODE_DEV;
	139	fh->fh_fsid[0] = new_encode_dev(MKDEV(ntohl(fh->fh_fsid[0]), ntohl(fh->fh_fsid[1])));
	140	fh->fh_fsid[1] = fh->fh_fsid[2];
	141	}
	142	data_left -= len;
	143	if (data_left < 0)
	144	return error;
	145	exp = rqst_exp_find(rqstp, fh->fh_fsid_type, fh->fh_auth);
	146	fid = (struct fid *)(fh->fh_auth + len);
	147	} else {
	148	__u32 tfh[2];
	149	dev_t xdev;
	150	ino_t xino;
	151
	152	if (fh->fh_size != NFS_FHSIZE)
	153	return error;
	154	/* assume old filehandle format */
	155	xdev = old_decode_dev(fh->ofh_xdev);
	156	xino = u32_to_ino_t(fh->ofh_xino);
	157	mk_fsid(FSID_DEV, tfh, xdev, xino, 0, NULL);
	158	exp = rqst_exp_find(rqstp, FSID_DEV, tfh);
	159	}
	160
	161	error = nfserr_stale;
	162	if (PTR_ERR(exp) == -ENOENT)
	163	return error;
	164
	165	if (IS_ERR(exp))
	166	return nfserrno(PTR_ERR(exp));
	167
496d6c32 NB	168	if (exp->ex_flags & NFSEXP_NOSUBTREECHECK) {
	169	/* Elevate privileges so that the lack of 'r' or 'x'
	170	* permission on some parent directory will
	171	* not stop exportfs_decode_fh from being able
	172	* to reconnect a directory into the dentry cache.
	173	* The same problem can affect "SUBTREECHECK" exports,
	174	* but as nfsd_acceptable depends on correct
	175	* access control settings being in effect, we cannot
	176	* fix that case easily.
	177	*/
d84f4f99 DH	178	struct cred *new = prepare_creds();
	179	if (!new)
	180	return nfserrno(-ENOMEM);
	181	new->cap_effective =
	182	cap_raise_nfsd_set(new->cap_effective,
	183	new->cap_permitted);
	184	put_cred(override_creds(new));
	185	put_cred(new);
496d6c32 NB	186	} else {
	187	error = nfsd_setuser_and_check_port(rqstp, exp);
	188	if (error)
	189	goto out;
	190	}
03550fac BF	191
	192	/*
	193	* Look up the dentry using the NFS file handle.
	194	*/
	195	error = nfserr_stale;
	196	if (rqstp->rq_vers > 2)
	197	error = nfserr_badhandle;
	198
	199	if (fh->fh_version != 1) {
	200	sfid.i32.ino = fh->ofh_ino;
	201	sfid.i32.gen = fh->ofh_generation;
	202	sfid.i32.parent_ino = fh->ofh_dirino;
	203	fid = &sfid;
	204	data_left = 3;
	205	if (fh->ofh_dirino == 0)
	206	fileid_type = FILEID_INO32_GEN;
	207	else
	208	fileid_type = FILEID_INO32_GEN_PARENT;
	209	} else
	210	fileid_type = fh->fh_fileid_type;
	211
	212	if (fileid_type == FILEID_ROOT)
	213	dentry = dget(exp->ex_path.dentry);
	214	else {
	215	dentry = exportfs_decode_fh(exp->ex_path.mnt, fid,
	216	data_left, fileid_type,
	217	nfsd_acceptable, exp);
	218	}
	219	if (dentry == NULL)
	220	goto out;
	221	if (IS_ERR(dentry)) {
	222	if (PTR_ERR(dentry) != -EINVAL)
	223	error = nfserrno(PTR_ERR(dentry));
	224	goto out;
	225	}
	226
	227	if (S_ISDIR(dentry->d_inode->i_mode) &&
	228	(dentry->d_flags & DCACHE_DISCONNECTED)) {
	229	printk("nfsd: find_fh_dentry returned a DISCONNECTED directory: %s/%s\n",
	230	dentry->d_parent->d_name.name, dentry->d_name.name);
	231	}
	232
	233	fhp->fh_dentry = dentry;
	234	fhp->fh_export = exp;
03550fac BF	235	return 0;
	236	out:
	237	exp_put(exp);
	238	return error;
	239	}
	240
b3d47676 BF	241	/**
	242	* fh_verify - filehandle lookup and access checking
	243	* @rqstp: pointer to current rpc request
	244	* @fhp: filehandle to be verified
	245	* @type: expected type of object pointed to by filehandle
	246	* @access: type of access needed to object
	247	*
	248	* Look up a dentry from the on-the-wire filehandle, check the client's
	249	* access to the export, and set the current task's credentials.
	250	*
	251	* Regardless of success or failure of fh_verify(), fh_put() should be
	252	* called on @fhp when the caller is finished with the filehandle.
	253	*
	254	* fh_verify() may be called multiple times on a given filehandle, for
	255	* example, when processing an NFSv4 compound. The first call will look
	256	* up a dentry using the on-the-wire filehandle. Subsequent calls will
	257	* skip the lookup and just perform the other checks and possibly change
	258	* the current task's credentials.
1da177e4	259	*
b3d47676 BF	260	* @type specifies the type of object expected using one of the S_IF*
	261	* constants defined in include/linux/stat.h. The caller may use zero
	262	* to indicate that it doesn't care, or a negative integer to indicate
	263	* that it expects something not of the given type.
1da177e4	264	*
b3d47676 BF	265	* @access is formed from the NFSD_MAY_* constants defined in
b3d47676 BF	266	* include/linux/nfsd/nfsd.h.
1da177e4	267	*/
83b11340	268	__be32
1da177e4 LT	269	fh_verify(struct svc_rqst rqstp, struct svc_fh fhp, int type, int access)
1da177e4 LT	270	{
03550fac	271	struct svc_export *exp;
1da177e4	272	struct dentry *dentry;
03550fac	273	__be32 error;
1da177e4 LT	274
	275	dprintk("nfsd: fh_verify(%s)\n", SVCFH_fmt(fhp));
	276
1da177e4	277	if (!fhp->fh_dentry) {
03550fac	278	error = nfsd_set_fh_dentry(rqstp, fhp);
d1bbf14f N	279	if (error)
d1bbf14f N	280	goto out;
1da177e4	281	}
864f0f61 BF	282	dentry = fhp->fh_dentry;
	283	exp = fhp->fh_export;
	284	/*
	285	* We still have to do all these permission checks, even when
	286	* fh_dentry is already set:
	287	* - fh_verify may be called multiple times with different
	288	* "access" arguments (e.g. nfsd_proc_create calls
	289	* fh_verify(...,NFSD_MAY_EXEC) first, then later (in
	290	* nfsd_create) calls fh_verify(...,NFSD_MAY_CREATE).
	291	* - in the NFSv4 case, the filehandle may have been filled
	292	* in by fh_compose, and given a dentry, but further
	293	* compound operations performed with that filehandle
	294	* still need permissions checks. In the worst case, a
	295	* mountpoint crossing may have changed the export
	296	* options, and we may now need to use a different uid
	297	* (for example, if different id-squashing options are in
	298	* effect on the new filesystem).
	299	*/
	300	error = nfsd_setuser_and_check_port(rqstp, exp);
	301	if (error)
	302	goto out;
7fc90ec9	303
1da177e4 LT	304	error = nfsd_mode_check(rqstp, dentry->d_inode->i_mode, type);
	305	if (error)
	306	goto out;
	307
04716e66 BF	308	/*
	309	* pseudoflavor restrictions are not enforced on NLM,
	310	* which clients virtually always use auth_sys for,
	311	* even while using RPCSEC_GSS for NFS.
	312	*/
	313	if (access & NFSD_MAY_LOCK)
	314	goto skip_pseudoflavor_check;
	315	/*
	316	* Clients may expect to be able to use auth_sys during mount,
	317	* even if they use gss for everything else; see section 2.3.2
	318	* of rfc 2623.
	319	*/
	320	if (access & NFSD_MAY_BYPASS_GSS_ON_ROOT
	321	&& exp->ex_path.dentry == dentry)
	322	goto skip_pseudoflavor_check;
	323
	324	error = check_nfsd_access(exp, rqstp);
	325	if (error)
	326	goto out;
32c1eb0c	327
04716e66	328	skip_pseudoflavor_check:
1da177e4	329	/* Finally, check access permissions. */
0ec757df	330	error = nfsd_permission(rqstp, exp, dentry, access);
1da177e4	331
1da177e4	332	if (error) {
34e9a63b N	333	dprintk("fh_verify: %s/%s permission failure, "
	334	"acc=%x, error=%d\n",
	335	dentry->d_parent->d_name.name,
	336	dentry->d_name.name,
fc2dd2e5	337	access, ntohl(error));
1da177e4	338	}
1da177e4	339	out:
1da177e4 LT	340	if (error == nfserr_stale)
	341	nfsdstats.fh_stale++;
	342	return error;
	343	}
	344
	345
	346	/*
	347	* Compose a file handle for an NFS reply.
	348	*
	349	* Note that when first composed, the dentry may not yet have
	350	* an inode. In this case a call to fh_update should be made
	351	* before the fh goes out on the wire ...
	352	*/
6e91ea2b CH	353	static void _fh_update(struct svc_fh fhp, struct svc_export exp,
6e91ea2b CH	354	struct dentry *dentry)
1da177e4	355	{
54775491	356	if (dentry != exp->ex_path.dentry) {
6e91ea2b CH	357	struct fid fid = (struct fid )
	358	(fhp->fh_handle.fh_auth + fhp->fh_handle.fh_size/4 - 1);
	359	int maxsize = (fhp->fh_maxsize - fhp->fh_handle.fh_size)/4;
	360	int subtreecheck = !(exp->ex_flags & NFSEXP_NOSUBTREECHECK);
1da177e4	361
6e91ea2b CH	362	fhp->fh_handle.fh_fileid_type =
	363	exportfs_encode_fh(dentry, fid, &maxsize, subtreecheck);
	364	fhp->fh_handle.fh_size += maxsize * 4;
	365	} else {
	366	fhp->fh_handle.fh_fileid_type = FILEID_ROOT;
	367	}
1da177e4 LT	368	}
	369
	370	/*
	371	* for composing old style file handles
	372	*/
	373	static inline void _fh_update_old(struct dentry *dentry,
	374	struct svc_export *exp,
	375	struct knfsd_fh *fh)
	376	{
	377	fh->ofh_ino = ino_t_to_u32(dentry->d_inode->i_ino);
	378	fh->ofh_generation = dentry->d_inode->i_generation;
	379	if (S_ISDIR(dentry->d_inode->i_mode) \|\|
	380	(exp->ex_flags & NFSEXP_NOSUBTREECHECK))
	381	fh->ofh_dirino = 0;
	382	}
	383
8e498751 BF	384	static bool is_root_export(struct svc_export *exp)
	385	{
	386	return exp->ex_path.dentry == exp->ex_path.dentry->d_sb->s_root;
	387	}
	388
	389	static struct super_block exp_sb(struct svc_export exp)
	390	{
	391	return exp->ex_path.dentry->d_inode->i_sb;
	392	}
	393
	394	static bool fsid_type_ok_for_exp(u8 fsid_type, struct svc_export *exp)
	395	{
	396	switch (fsid_type) {
	397	case FSID_DEV:
	398	if (!old_valid_dev(exp_sb(exp)->s_dev))
	399	return 0;
	400	/* FALL THROUGH */
	401	case FSID_MAJOR_MINOR:
	402	case FSID_ENCODE_DEV:
	403	return exp_sb(exp)->s_type->fs_flags & FS_REQUIRES_DEV;
	404	case FSID_NUM:
	405	return exp->ex_flags & NFSEXP_FSID;
	406	case FSID_UUID8:
	407	case FSID_UUID16:
	408	if (!is_root_export(exp))
	409	return 0;
	410	/* fall through */
	411	case FSID_UUID4_INUM:
	412	case FSID_UUID16_INUM:
	413	return exp->ex_uuid != NULL;
	414	}
	415	return 1;
	416	}
	417
1da177e4	418
bc6c53d5 BF	419	static void set_version_and_fsid_type(struct svc_fh fhp, struct svc_export exp, struct svc_fh *ref_fh)
bc6c53d5 BF	420	{
b41eeef1	421	u8 version;
bc6c53d5 BF	422	u8 fsid_type;
bc6c53d5 BF	423	retry:
b41eeef1	424	version = 1;
7e405364	425	if (ref_fh && ref_fh->fh_export == exp) {
982aedfd	426	version = ref_fh->fh_handle.fh_version;
b41eeef1 N	427	fsid_type = ref_fh->fh_handle.fh_fsid_type;
b41eeef1 N	428
b41eeef1 N	429	ref_fh = NULL;
	430
	431	switch (version) {
	432	case 0xca:
af6a4e28	433	fsid_type = FSID_DEV;
b41eeef1 N	434	break;
	435	case 1:
	436	break;
	437	default:
	438	goto retry;
	439	}
	440
8e498751 BF	441	/*
	442	* As the fsid -> filesystem mapping was guided by
	443	* user-space, there is no guarantee that the filesystem
	444	* actually supports that fsid type. If it doesn't we
	445	* loop around again without ref_fh set.
982aedfd	446	*/
8e498751 BF	447	if (!fsid_type_ok_for_exp(fsid_type, exp))
8e498751 BF	448	goto retry;
30fa8c01 SD	449	} else if (exp->ex_flags & NFSEXP_FSID) {
30fa8c01 SD	450	fsid_type = FSID_NUM;
af6a4e28 N	451	} else if (exp->ex_uuid) {
af6a4e28 N	452	if (fhp->fh_maxsize >= 64) {
8e498751	453	if (is_root_export(exp))
af6a4e28 N	454	fsid_type = FSID_UUID16;
	455	else
	456	fsid_type = FSID_UUID16_INUM;
	457	} else {
8e498751	458	if (is_root_export(exp))
af6a4e28 N	459	fsid_type = FSID_UUID8;
	460	else
	461	fsid_type = FSID_UUID4_INUM;
	462	}
bc6c53d5	463	} else if (!old_valid_dev(exp_sb(exp)->s_dev))
1da177e4	464	/* for newer device numbers, we must use a newer fsid format */
af6a4e28	465	fsid_type = FSID_ENCODE_DEV;
982aedfd	466	else
af6a4e28	467	fsid_type = FSID_DEV;
bc6c53d5 BF	468	fhp->fh_handle.fh_version = version;
	469	if (version)
	470	fhp->fh_handle.fh_fsid_type = fsid_type;
	471	}
	472
	473	__be32
	474	fh_compose(struct svc_fh fhp, struct svc_export exp, struct dentry *dentry,
	475	struct svc_fh *ref_fh)
	476	{
	477	/* ref_fh is a reference file handle.
	478	* if it is non-null and for the same filesystem, then we should compose
	479	* a filehandle which is of the same version, where possible.
	480	* Currently, that means that if ref_fh->fh_handle.fh_version == 0xca
	481	* Then create a 32byte filehandle using nfs_fhbase_old
	482	*
	483	*/
	484
	485	struct inode * inode = dentry->d_inode;
	486	struct dentry *parent = dentry->d_parent;
	487	__u32 *datap;
	488	dev_t ex_dev = exp_sb(exp)->s_dev;
	489
	490	dprintk("nfsd: fh_compose(exp %02x:%02x/%ld %s/%s, ino=%ld)\n",
	491	MAJOR(ex_dev), MINOR(ex_dev),
	492	(long) exp->ex_path.dentry->d_inode->i_ino,
	493	parent->d_name.name, dentry->d_name.name,
	494	(inode ? inode->i_ino : 0));
	495
	496	/* Choose filehandle version and fsid type based on
	497	* the reference filehandle (if it is in the same export)
	498	* or the export options.
	499	*/
	500	set_version_and_fsid_type(fhp, exp, ref_fh);
1da177e4 LT	501
	502	if (ref_fh == fhp)
	503	fh_put(ref_fh);
	504
	505	if (fhp->fh_locked \|\| fhp->fh_dentry) {
	506	printk(KERN_ERR "fh_compose: fh %s/%s not initialized!\n",
982aedfd	507	parent->d_name.name, dentry->d_name.name);
1da177e4 LT	508	}
	509	if (fhp->fh_maxsize < NFS_FHSIZE)
	510	printk(KERN_ERR "fh_compose: called with maxsize %d! %s/%s\n",
982aedfd N	511	fhp->fh_maxsize,
982aedfd N	512	parent->d_name.name, dentry->d_name.name);
1da177e4 LT	513
	514	fhp->fh_dentry = dget(dentry); /* our internal copy */
	515	fhp->fh_export = exp;
	516	cache_get(&exp->h);
	517
bc6c53d5	518	if (fhp->fh_handle.fh_version == 0xca) {
1da177e4 LT	519	/* old style filehandle please */
	520	memset(&fhp->fh_handle.fh_base, 0, NFS_FHSIZE);
	521	fhp->fh_handle.fh_size = NFS_FHSIZE;
	522	fhp->fh_handle.ofh_dcookie = 0xfeebbaca;
	523	fhp->fh_handle.ofh_dev = old_encode_dev(ex_dev);
	524	fhp->fh_handle.ofh_xdev = fhp->fh_handle.ofh_dev;
982aedfd	525	fhp->fh_handle.ofh_xino =
54775491	526	ino_t_to_u32(exp->ex_path.dentry->d_inode->i_ino);
1da177e4 LT	527	fhp->fh_handle.ofh_dirino = ino_t_to_u32(parent_ino(dentry));
	528	if (inode)
	529	_fh_update_old(dentry, exp, &fhp->fh_handle);
	530	} else {
	531	int len;
1da177e4 LT	532	fhp->fh_handle.fh_auth_type = 0;
1da177e4 LT	533	datap = fhp->fh_handle.fh_auth+0;
bc6c53d5	534	mk_fsid(fhp->fh_handle.fh_fsid_type, datap, ex_dev,
54775491	535	exp->ex_path.dentry->d_inode->i_ino,
af6a4e28 N	536	exp->ex_fsid, exp->ex_uuid);
af6a4e28 N	537
bc6c53d5	538	len = key_len(fhp->fh_handle.fh_fsid_type);
1da177e4 LT	539	datap += len/4;
	540	fhp->fh_handle.fh_size = 4 + len;
	541
6e91ea2b CH	542	if (inode)
6e91ea2b CH	543	_fh_update(fhp, exp, dentry);
1be10a88 BF	544	if (fhp->fh_handle.fh_fileid_type == 255) {
1be10a88 BF	545	fh_put(fhp);
1da177e4	546	return nfserr_opnotsupp;
1be10a88	547	}
1da177e4 LT	548	}
1da177e4 LT	549
1da177e4 LT	550	return 0;
	551	}
	552
	553	/*
	554	* Update file handle information after changing a dentry.
	555	* This is only called by nfsd_create, nfsd_create_v3 and nfsd_proc_create
	556	*/
83b11340	557	__be32
1da177e4 LT	558	fh_update(struct svc_fh *fhp)
	559	{
	560	struct dentry *dentry;
982aedfd	561
1da177e4 LT	562	if (!fhp->fh_dentry)
	563	goto out_bad;
	564
	565	dentry = fhp->fh_dentry;
	566	if (!dentry->d_inode)
	567	goto out_negative;
	568	if (fhp->fh_handle.fh_version != 1) {
	569	_fh_update_old(dentry, fhp->fh_export, &fhp->fh_handle);
	570	} else {
6e91ea2b	571	if (fhp->fh_handle.fh_fileid_type != FILEID_ROOT)
4c9608b2	572	goto out;
6e91ea2b CH	573
6e91ea2b CH	574	_fh_update(fhp, fhp->fh_export, dentry);
1da177e4 LT	575	if (fhp->fh_handle.fh_fileid_type == 255)
	576	return nfserr_opnotsupp;
	577	}
	578	out:
	579	return 0;
	580
	581	out_bad:
	582	printk(KERN_ERR "fh_update: fh not verified!\n");
	583	goto out;
	584	out_negative:
	585	printk(KERN_ERR "fh_update: %s/%s still negative!\n",
	586	dentry->d_parent->d_name.name, dentry->d_name.name);
	587	goto out;
1da177e4 LT	588	}
	589
	590	/*
	591	* Release a file handle.
	592	*/
	593	void
	594	fh_put(struct svc_fh *fhp)
	595	{
	596	struct dentry * dentry = fhp->fh_dentry;
	597	struct svc_export * exp = fhp->fh_export;
	598	if (dentry) {
	599	fh_unlock(fhp);
	600	fhp->fh_dentry = NULL;
	601	dput(dentry);
	602	#ifdef CONFIG_NFSD_V3
	603	fhp->fh_pre_saved = 0;
	604	fhp->fh_post_saved = 0;
	605	#endif
1da177e4 LT	606	}
1da177e4 LT	607	if (exp) {
baab935f	608	cache_put(&exp->h, &svc_export_cache);
1da177e4 LT	609	fhp->fh_export = NULL;
	610	}
	611	return;
	612	}
	613
	614	/*
	615	* Shorthand for dprintk()'s
	616	*/
	617	char * SVCFH_fmt(struct svc_fh *fhp)
	618	{
	619	struct knfsd_fh *fh = &fhp->fh_handle;
	620
	621	static char buf[80];
	622	sprintf(buf, "%d: %08x %08x %08x %08x %08x %08x",
	623	fh->fh_size,
	624	fh->fh_base.fh_pad[0],
	625	fh->fh_base.fh_pad[1],
	626	fh->fh_base.fh_pad[2],
	627	fh->fh_base.fh_pad[3],
	628	fh->fh_base.fh_pad[4],
	629	fh->fh_base.fh_pad[5]);
	630	return buf;
	631	}
af6a4e28 N	632
	633	enum fsid_source fsid_source(struct svc_fh *fhp)
	634	{
	635	if (fhp->fh_handle.fh_version != 1)
	636	return FSIDSOURCE_DEV;
	637	switch(fhp->fh_handle.fh_fsid_type) {
	638	case FSID_DEV:
	639	case FSID_ENCODE_DEV:
	640	case FSID_MAJOR_MINOR:
8e498751	641	if (exp_sb(fhp->fh_export)->s_type->fs_flags & FS_REQUIRES_DEV)
b8da0d1c NB	642	return FSIDSOURCE_DEV;
b8da0d1c NB	643	break;
af6a4e28	644	case FSID_NUM:
af6a4e28 N	645	if (fhp->fh_export->ex_flags & NFSEXP_FSID)
af6a4e28 N	646	return FSIDSOURCE_FSID;
b8da0d1c NB	647	break;
	648	default:
	649	break;
af6a4e28	650	}
b8da0d1c NB	651	/* either a UUID type filehandle, or the filehandle doesn't
	652	* match the export.
	653	*/
	654	if (fhp->fh_export->ex_flags & NFSEXP_FSID)
	655	return FSIDSOURCE_FSID;
	656	if (fhp->fh_export->ex_uuid)
	657	return FSIDSOURCE_UUID;
	658	return FSIDSOURCE_DEV;
af6a4e28	659	}