[net-next-2.6.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/slab.h>
#include <linux/smp_lock.h>
#include <linux/fs.h>
#include <linux/unistd.h>
#include <linux/string.h>
#include <linux/stat.h>
#include <linux/dcache.h>
#include <linux/mount.h>
#include <asm/pgtable.h>

#include <linux/sunrpc/clnt.h>
#include <linux/sunrpc/svc.h>
#include <linux/nfsd/nfsd.h>

#define NFSDDBG_FACILITY		NFSDDBG_FH


static int nfsd_nr_verified;
static int nfsd_nr_put;

extern struct export_operations export_op_default;

#define	CALL(ops,fun) ((ops->fun)?(ops->fun):export_op_default.fun)

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

/*
 * Perform sanity checks on the dentry in a client's file handle.
 *
 * Note that the file handle dentry may need to be freed even after
 * an error return.
 *
 * This is only called at the start of an nfsproc call, so fhp points to
 * a svc_fh which is all 0 except for the over-the-wire file handle.
 */
__be32
fh_verify(struct svc_rqst *rqstp, struct svc_fh *fhp, int type, int access)
{
	struct knfsd_fh	*fh = &fhp->fh_handle;
	struct svc_export *exp = NULL;
	struct dentry	*dentry;
	__be32		error = 0;

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

	if (!fhp->fh_dentry) {
		__u32 *datap=NULL;
		__u32 tfh[3];		/* filehandle fragment for oldstyle filehandles */
		int fileid_type;
		int data_left = fh->fh_size/4;

		error = nfserr_stale;
		if (rqstp->rq_client == NULL)
			goto out;
		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;
			datap = fh->fh_auth;
			if (--data_left<0) goto out;
			switch (fh->fh_auth_type) {
			case 0: break;
			default: goto out;
			}
			len = key_len(fh->fh_fsid_type) / 4;
			if (len == 0) goto out;
			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];
			}
			if ((data_left -= len)<0) goto out;
			exp = exp_find(rqstp->rq_client, fh->fh_fsid_type, datap, &rqstp->rq_chandle);
			datap += len;
		} else {
			dev_t xdev;
			ino_t xino;
			if (fh->fh_size != NFS_FHSIZE)
				goto out;
			/* 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 = exp_find(rqstp->rq_client, FSID_DEV, tfh,
				       &rqstp->rq_chandle);
		}

		if (IS_ERR(exp) && (PTR_ERR(exp) == -EAGAIN
				|| PTR_ERR(exp) == -ETIMEDOUT)) {
			error = nfserrno(PTR_ERR(exp));
			goto out;
		}

		error = nfserr_stale; 
		if (!exp || IS_ERR(exp))
			goto out;

		/* Check if the request originated from a secure port. */
		error = nfserr_perm;
		if (!rqstp->rq_secure && EX_SECURE(exp)) {
			char buf[RPC_MAX_ADDRBUFLEN];
			printk(KERN_WARNING
			       "nfsd: request from insecure port %s!\n",
			       svc_print_addr(rqstp, buf, sizeof(buf)));
			goto out;
		}

		/* Set user creds for this exportpoint */
		error = nfserrno(nfsd_setuser(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) {
			tfh[0] = fh->ofh_ino;
			tfh[1] = fh->ofh_generation;
			tfh[2] = fh->ofh_dirino;
			datap = tfh;
			data_left = 3;
			if (fh->ofh_dirino == 0)
				fileid_type = 1;
			else
				fileid_type = 2;
		} else
			fileid_type = fh->fh_fileid_type;

		if (fileid_type == 0)
			dentry = dget(exp->ex_dentry);
		else {
			struct export_operations *nop = exp->ex_mnt->mnt_sb->s_export_op;
			dentry = CALL(nop,decode_fh)(exp->ex_mnt->mnt_sb,
						     datap, 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;
		nfsd_nr_verified++;
	} else {
		/* just rechecking permissions
		 * (e.g. nfsproc_create calls fh_verify, then nfsd_create does as well)
		 */
		dprintk("nfsd: fh_verify - just checking\n");
		dentry = fhp->fh_dentry;
		exp = fhp->fh_export;
		/* Set user creds for this exportpoint; necessary even
		 * in the "just checking" case because this may be a
		 * filehandle that was created by fh_compose, and that
		 * is about to be used in another nfsv4 compound
		 * operation */
		error = nfserrno(nfsd_setuser(rqstp, exp));
		if (error)
			goto out;
	}
	cache_get(&exp->h);


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

	/* Finally, check access permissions. */
	error = nfsd_permission(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 (exp && !IS_ERR(exp))
		exp_put(exp);
	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 inline int _fh_update(struct dentry *dentry, struct svc_export *exp,
			     __u32 *datap, int *maxsize)
{
	struct export_operations *nop = exp->ex_mnt->mnt_sb->s_export_op;

	if (dentry == exp->ex_dentry) {
		*maxsize = 0;
		return 0;
	}

	return CALL(nop,encode_fh)(dentry, datap, maxsize,
			  !(exp->ex_flags&NFSEXP_NOSUBTREECHECK));
}

/*
 * 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;
}

__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
	 *
	 */

	u8 version = 1;
	u8 fsid_type = 0;
	struct inode * inode = dentry->d_inode;
	struct dentry *parent = dentry->d_parent;
	__u32 *datap;
	dev_t ex_dev = exp->ex_dentry->d_inode->i_sb->s_dev;
	int root_export = (exp->ex_dentry == exp->ex_dentry->d_sb->s_root);

	dprintk("nfsd: fh_compose(exp %02x:%02x/%ld %s/%s, ino=%ld)\n",
		MAJOR(ex_dev), MINOR(ex_dev),
		(long) exp->ex_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.
	 */
	if (ref_fh && ref_fh->fh_export == exp) {
		version = ref_fh->fh_handle.fh_version;
		if (version == 0xca)
			fsid_type = FSID_DEV;
		else
			fsid_type = ref_fh->fh_handle.fh_fsid_type;
		/* We know this version/type works for this export
		 * so there is no need for further checks.
		 */
	} else if (exp->ex_uuid) {
		if (fhp->fh_maxsize >= 64) {
			if (root_export)
				fsid_type = FSID_UUID16;
			else
				fsid_type = FSID_UUID16_INUM;
		} else {
			if (root_export)
				fsid_type = FSID_UUID8;
			else
				fsid_type = FSID_UUID4_INUM;
		}
	} else if (exp->ex_flags & NFSEXP_FSID)
		fsid_type = FSID_NUM;
	else if (!old_valid_dev(ex_dev))
		/* for newer device numbers, we must use a newer fsid format */
		fsid_type = FSID_ENCODE_DEV;
	else
		fsid_type = FSID_DEV;

	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 (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_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_version = 1;
		fhp->fh_handle.fh_auth_type = 0;
		datap = fhp->fh_handle.fh_auth+0;
		fhp->fh_handle.fh_fsid_type = fsid_type;
		mk_fsid(fsid_type, datap, ex_dev,
			exp->ex_dentry->d_inode->i_ino,
			exp->ex_fsid, exp->ex_uuid);

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

		if (inode) {
			int size = (fhp->fh_maxsize-len-4)/4;
			fhp->fh_handle.fh_fileid_type =
				_fh_update(dentry, exp, datap, &size);
			fhp->fh_handle.fh_size += size*4;
		}
		if (fhp->fh_handle.fh_fileid_type == 255)
			return nfserr_opnotsupp;
	}

	nfsd_nr_verified++;
	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;
	__u32 *datap;

	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 {
		int size;
		if (fhp->fh_handle.fh_fileid_type != 0)
			goto out;
		datap = fhp->fh_handle.fh_auth+
			fhp->fh_handle.fh_size/4 -1;
		size = (fhp->fh_maxsize - fhp->fh_handle.fh_size)/4;
		fhp->fh_handle.fh_fileid_type =
			_fh_update(dentry, fhp->fh_export, datap, &size);
		fhp->fh_handle.fh_size += size*4;
		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
		nfsd_nr_put++;
	}
	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:
		return FSIDSOURCE_DEV;
	case FSID_NUM:
		return FSIDSOURCE_FSID;
	default:
		if (fhp->fh_export->ex_flags & NFSEXP_FSID)
			return FSIDSOURCE_FSID;
		else
			return FSIDSOURCE_UUID;
	}
}
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
1da177e4 LT	12	#include <linux/slab.h>
	13	#include <linux/smp_lock.h>
	14	#include <linux/fs.h>
	15	#include <linux/unistd.h>
	16	#include <linux/string.h>
	17	#include <linux/stat.h>
	18	#include <linux/dcache.h>
	19	#include <linux/mount.h>
	20	#include <asm/pgtable.h>
	21
ad06e4bd	22	#include <linux/sunrpc/clnt.h>
1da177e4 LT	23	#include <linux/sunrpc/svc.h>
	24	#include <linux/nfsd/nfsd.h>
	25
	26	#define NFSDDBG_FACILITY NFSDDBG_FH
1da177e4 LT	27
	28
	29	static int nfsd_nr_verified;
	30	static int nfsd_nr_put;
	31
	32	extern struct export_operations export_op_default;
	33
	34	#define CALL(ops,fun) ((ops->fun)?(ops->fun):export_op_default.fun)
	35
	36	/*
	37	* our acceptability function.
	38	* if NOSUBTREECHECK, accept anything
	39	* if not, require that we can walk up to exp->ex_dentry
	40	* doing some checks on the 'x' bits
	41	*/
	42	static int nfsd_acceptable(void expv, struct dentry dentry)
	43	{
	44	struct svc_export *exp = expv;
	45	int rv;
	46	struct dentry *tdentry;
	47	struct dentry *parent;
	48
	49	if (exp->ex_flags & NFSEXP_NOSUBTREECHECK)
	50	return 1;
	51
	52	tdentry = dget(dentry);
	53	while (tdentry != exp->ex_dentry && ! IS_ROOT(tdentry)) {
	54	/* make sure parents give x permission to user */
	55	int err;
	56	parent = dget_parent(tdentry);
	57	err = permission(parent->d_inode, MAY_EXEC, NULL);
	58	if (err < 0) {
	59	dput(parent);
	60	break;
	61	}
	62	dput(tdentry);
	63	tdentry = parent;
	64	}
	65	if (tdentry != exp->ex_dentry)
	66	dprintk("nfsd_acceptable failed at %p %s\n", tdentry, tdentry->d_name.name);
	67	rv = (tdentry == exp->ex_dentry);
	68	dput(tdentry);
	69	return rv;
	70	}
	71
	72	/* Type check. The correct error return for type mismatches does not seem to be
	73	* generally agreed upon. SunOS seems to use EISDIR if file isn't S_IFREG; a
	74	* comment in the NFSv3 spec says this is incorrect (implementation notes for
	75	* the write call).
	76	*/
83b11340	77	static inline __be32
1da177e4 LT	78	nfsd_mode_check(struct svc_rqst *rqstp, umode_t mode, int type)
	79	{
	80	/* Type can be negative when creating hardlinks - not to a dir */
	81	if (type > 0 && (mode & S_IFMT) != type) {
	82	if (rqstp->rq_vers == 4 && (mode & S_IFMT) == S_IFLNK)
	83	return nfserr_symlink;
	84	else if (type == S_IFDIR)
	85	return nfserr_notdir;
	86	else if ((mode & S_IFMT) == S_IFDIR)
	87	return nfserr_isdir;
	88	else
	89	return nfserr_inval;
	90	}
	91	if (type < 0 && (mode & S_IFMT) == -type) {
	92	if (rqstp->rq_vers == 4 && (mode & S_IFMT) == S_IFLNK)
	93	return nfserr_symlink;
	94	else if (type == -S_IFDIR)
	95	return nfserr_isdir;
	96	else
	97	return nfserr_notdir;
	98	}
	99	return 0;
	100	}
	101
	102	/*
	103	* Perform sanity checks on the dentry in a client's file handle.
	104	*
	105	* Note that the file handle dentry may need to be freed even after
	106	* an error return.
	107	*
	108	* This is only called at the start of an nfsproc call, so fhp points to
	109	* a svc_fh which is all 0 except for the over-the-wire file handle.
	110	*/
83b11340	111	__be32
1da177e4 LT	112	fh_verify(struct svc_rqst rqstp, struct svc_fh fhp, int type, int access)
	113	{
	114	struct knfsd_fh *fh = &fhp->fh_handle;
	115	struct svc_export *exp = NULL;
	116	struct dentry *dentry;
83b11340	117	__be32 error = 0;
1da177e4 LT	118
	119	dprintk("nfsd: fh_verify(%s)\n", SVCFH_fmt(fhp));
	120
1da177e4 LT	121	if (!fhp->fh_dentry) {
	122	__u32 *datap=NULL;
	123	__u32 tfh[3]; /* filehandle fragment for oldstyle filehandles */
	124	int fileid_type;
	125	int data_left = fh->fh_size/4;
	126
	127	error = nfserr_stale;
	128	if (rqstp->rq_client == NULL)
	129	goto out;
	130	if (rqstp->rq_vers > 2)
	131	error = nfserr_badhandle;
	132	if (rqstp->rq_vers == 4 && fh->fh_size == 0)
	133	return nfserr_nofilehandle;
	134
	135	if (fh->fh_version == 1) {
	136	int len;
	137	datap = fh->fh_auth;
	138	if (--data_left<0) goto out;
	139	switch (fh->fh_auth_type) {
	140	case 0: break;
	141	default: goto out;
	142	}
	143	len = key_len(fh->fh_fsid_type) / 4;
	144	if (len == 0) goto out;
af6a4e28	145	if (fh->fh_fsid_type == FSID_MAJOR_MINOR) {
1da177e4	146	/* deprecated, convert to type 3 */
af6a4e28 N	147	len = key_len(FSID_ENCODE_DEV)/4;
af6a4e28 N	148	fh->fh_fsid_type = FSID_ENCODE_DEV;
1da177e4 LT	149	fh->fh_fsid[0] = new_encode_dev(MKDEV(ntohl(fh->fh_fsid[0]), ntohl(fh->fh_fsid[1])));
	150	fh->fh_fsid[1] = fh->fh_fsid[2];
	151	}
	152	if ((data_left -= len)<0) goto out;
	153	exp = exp_find(rqstp->rq_client, fh->fh_fsid_type, datap, &rqstp->rq_chandle);
	154	datap += len;
	155	} else {
	156	dev_t xdev;
	157	ino_t xino;
	158	if (fh->fh_size != NFS_FHSIZE)
	159	goto out;
	160	/* assume old filehandle format */
	161	xdev = old_decode_dev(fh->ofh_xdev);
	162	xino = u32_to_ino_t(fh->ofh_xino);
af6a4e28 N	163	mk_fsid(FSID_DEV, tfh, xdev, xino, 0, NULL);
	164	exp = exp_find(rqstp->rq_client, FSID_DEV, tfh,
	165	&rqstp->rq_chandle);
1da177e4 LT	166	}
1da177e4 LT	167
e0bb89ef BF	168	if (IS_ERR(exp) && (PTR_ERR(exp) == -EAGAIN
	169	\|\| PTR_ERR(exp) == -ETIMEDOUT)) {
	170	error = nfserrno(PTR_ERR(exp));
1da177e4	171	goto out;
e0bb89ef	172	}
1da177e4 LT	173
	174	error = nfserr_stale;
	175	if (!exp \|\| IS_ERR(exp))
	176	goto out;
	177
	178	/* Check if the request originated from a secure port. */
	179	error = nfserr_perm;
	180	if (!rqstp->rq_secure && EX_SECURE(exp)) {
ad06e4bd	181	char buf[RPC_MAX_ADDRBUFLEN];
1da177e4	182	printk(KERN_WARNING
ad06e4bd CL	183	"nfsd: request from insecure port %s!\n",
ad06e4bd CL	184	svc_print_addr(rqstp, buf, sizeof(buf)));
1da177e4 LT	185	goto out;
	186	}
	187
d1bbf14f N	188	/* Set user creds for this exportpoint */
	189	error = nfserrno(nfsd_setuser(rqstp, exp));
	190	if (error)
	191	goto out;
	192
1da177e4 LT	193	/*
	194	* Look up the dentry using the NFS file handle.
	195	*/
	196	error = nfserr_stale;
	197	if (rqstp->rq_vers > 2)
	198	error = nfserr_badhandle;
	199
	200	if (fh->fh_version != 1) {
	201	tfh[0] = fh->ofh_ino;
	202	tfh[1] = fh->ofh_generation;
	203	tfh[2] = fh->ofh_dirino;
	204	datap = tfh;
	205	data_left = 3;
	206	if (fh->ofh_dirino == 0)
	207	fileid_type = 1;
	208	else
	209	fileid_type = 2;
	210	} else
	211	fileid_type = fh->fh_fileid_type;
982aedfd	212
1da177e4 LT	213	if (fileid_type == 0)
	214	dentry = dget(exp->ex_dentry);
	215	else {
	216	struct export_operations *nop = exp->ex_mnt->mnt_sb->s_export_op;
	217	dentry = CALL(nop,decode_fh)(exp->ex_mnt->mnt_sb,
	218	datap, data_left,
	219	fileid_type,
	220	nfsd_acceptable, exp);
	221	}
	222	if (dentry == NULL)
	223	goto out;
	224	if (IS_ERR(dentry)) {
	225	if (PTR_ERR(dentry) != -EINVAL)
	226	error = nfserrno(PTR_ERR(dentry));
	227	goto out;
	228	}
34e9a63b	229
1da177e4 LT	230	if (S_ISDIR(dentry->d_inode->i_mode) &&
	231	(dentry->d_flags & DCACHE_DISCONNECTED)) {
	232	printk("nfsd: find_fh_dentry returned a DISCONNECTED directory: %s/%s\n",
	233	dentry->d_parent->d_name.name, dentry->d_name.name);
	234	}
1da177e4 LT	235
	236	fhp->fh_dentry = dentry;
	237	fhp->fh_export = exp;
	238	nfsd_nr_verified++;
	239	} else {
	240	/* just rechecking permissions
	241	* (e.g. nfsproc_create calls fh_verify, then nfsd_create does as well)
	242	*/
	243	dprintk("nfsd: fh_verify - just checking\n");
	244	dentry = fhp->fh_dentry;
	245	exp = fhp->fh_export;
d1bbf14f N	246	/* Set user creds for this exportpoint; necessary even
	247	* in the "just checking" case because this may be a
	248	* filehandle that was created by fh_compose, and that
	249	* is about to be used in another nfsv4 compound
	250	* operation */
	251	error = nfserrno(nfsd_setuser(rqstp, exp));
	252	if (error)
	253	goto out;
1da177e4 LT	254	}
	255	cache_get(&exp->h);
	256
7fc90ec9	257
1da177e4 LT	258	error = nfsd_mode_check(rqstp, dentry->d_inode->i_mode, type);
	259	if (error)
	260	goto out;
	261
	262	/* Finally, check access permissions. */
	263	error = nfsd_permission(exp, dentry, access);
	264
1da177e4	265	if (error) {
34e9a63b N	266	dprintk("fh_verify: %s/%s permission failure, "
	267	"acc=%x, error=%d\n",
	268	dentry->d_parent->d_name.name,
	269	dentry->d_name.name,
fc2dd2e5	270	access, ntohl(error));
1da177e4	271	}
1da177e4 LT	272	out:
	273	if (exp && !IS_ERR(exp))
	274	exp_put(exp);
	275	if (error == nfserr_stale)
	276	nfsdstats.fh_stale++;
	277	return error;
	278	}
	279
	280
	281	/*
	282	* Compose a file handle for an NFS reply.
	283	*
	284	* Note that when first composed, the dentry may not yet have
	285	* an inode. In this case a call to fh_update should be made
	286	* before the fh goes out on the wire ...
	287	*/
	288	static inline int _fh_update(struct dentry dentry, struct svc_export exp,
	289	__u32 datap, int maxsize)
	290	{
	291	struct export_operations *nop = exp->ex_mnt->mnt_sb->s_export_op;
982aedfd	292
1da177e4 LT	293	if (dentry == exp->ex_dentry) {
	294	*maxsize = 0;
	295	return 0;
	296	}
	297
	298	return CALL(nop,encode_fh)(dentry, datap, maxsize,
	299	!(exp->ex_flags&NFSEXP_NOSUBTREECHECK));
	300	}
	301
	302	/*
	303	* for composing old style file handles
	304	*/
	305	static inline void _fh_update_old(struct dentry *dentry,
	306	struct svc_export *exp,
	307	struct knfsd_fh *fh)
	308	{
	309	fh->ofh_ino = ino_t_to_u32(dentry->d_inode->i_ino);
	310	fh->ofh_generation = dentry->d_inode->i_generation;
	311	if (S_ISDIR(dentry->d_inode->i_mode) \|\|
	312	(exp->ex_flags & NFSEXP_NOSUBTREECHECK))
	313	fh->ofh_dirino = 0;
	314	}
	315
83b11340	316	__be32
982aedfd N	317	fh_compose(struct svc_fh fhp, struct svc_export exp, struct dentry *dentry,
982aedfd N	318	struct svc_fh *ref_fh)
1da177e4 LT	319	{
1da177e4 LT	320	/* ref_fh is a reference file handle.
7e405364 N	321	* if it is non-null and for the same filesystem, then we should compose
7e405364 N	322	* a filehandle which is of the same version, where possible.
1da177e4 LT	323	* Currently, that means that if ref_fh->fh_handle.fh_version == 0xca
	324	* Then create a 32byte filehandle using nfs_fhbase_old
	325	*
	326	*/
	327
982aedfd N	328	u8 version = 1;
982aedfd N	329	u8 fsid_type = 0;
1da177e4 LT	330	struct inode * inode = dentry->d_inode;
	331	struct dentry *parent = dentry->d_parent;
	332	__u32 *datap;
	333	dev_t ex_dev = exp->ex_dentry->d_inode->i_sb->s_dev;
af6a4e28	334	int root_export = (exp->ex_dentry == exp->ex_dentry->d_sb->s_root);
1da177e4 LT	335
	336	dprintk("nfsd: fh_compose(exp %02x:%02x/%ld %s/%s, ino=%ld)\n",
	337	MAJOR(ex_dev), MINOR(ex_dev),
	338	(long) exp->ex_dentry->d_inode->i_ino,
	339	parent->d_name.name, dentry->d_name.name,
	340	(inode ? inode->i_ino : 0));
	341
982aedfd N	342	/* Choose filehandle version and fsid type based on
	343	* the reference filehandle (if it is in the same export)
	344	* or the export options.
	345	*/
7e405364	346	if (ref_fh && ref_fh->fh_export == exp) {
982aedfd N	347	version = ref_fh->fh_handle.fh_version;
982aedfd N	348	if (version == 0xca)
af6a4e28	349	fsid_type = FSID_DEV;
1da177e4	350	else
982aedfd N	351	fsid_type = ref_fh->fh_handle.fh_fsid_type;
	352	/* We know this version/type works for this export
	353	* so there is no need for further checks.
	354	*/
af6a4e28 N	355	} else if (exp->ex_uuid) {
	356	if (fhp->fh_maxsize >= 64) {
	357	if (root_export)
	358	fsid_type = FSID_UUID16;
	359	else
	360	fsid_type = FSID_UUID16_INUM;
	361	} else {
	362	if (root_export)
	363	fsid_type = FSID_UUID8;
	364	else
	365	fsid_type = FSID_UUID4_INUM;
	366	}
1da177e4	367	} else if (exp->ex_flags & NFSEXP_FSID)
af6a4e28	368	fsid_type = FSID_NUM;
982aedfd	369	else if (!old_valid_dev(ex_dev))
1da177e4	370	/* for newer device numbers, we must use a newer fsid format */
af6a4e28	371	fsid_type = FSID_ENCODE_DEV;
982aedfd	372	else
af6a4e28	373	fsid_type = FSID_DEV;
1da177e4 LT	374
	375	if (ref_fh == fhp)
	376	fh_put(ref_fh);
	377
	378	if (fhp->fh_locked \|\| fhp->fh_dentry) {
	379	printk(KERN_ERR "fh_compose: fh %s/%s not initialized!\n",
982aedfd	380	parent->d_name.name, dentry->d_name.name);
1da177e4 LT	381	}
	382	if (fhp->fh_maxsize < NFS_FHSIZE)
	383	printk(KERN_ERR "fh_compose: called with maxsize %d! %s/%s\n",
982aedfd N	384	fhp->fh_maxsize,
982aedfd N	385	parent->d_name.name, dentry->d_name.name);
1da177e4 LT	386
	387	fhp->fh_dentry = dget(dentry); /* our internal copy */
	388	fhp->fh_export = exp;
	389	cache_get(&exp->h);
	390
982aedfd	391	if (version == 0xca) {
1da177e4 LT	392	/* old style filehandle please */
	393	memset(&fhp->fh_handle.fh_base, 0, NFS_FHSIZE);
	394	fhp->fh_handle.fh_size = NFS_FHSIZE;
	395	fhp->fh_handle.ofh_dcookie = 0xfeebbaca;
	396	fhp->fh_handle.ofh_dev = old_encode_dev(ex_dev);
	397	fhp->fh_handle.ofh_xdev = fhp->fh_handle.ofh_dev;
982aedfd N	398	fhp->fh_handle.ofh_xino =
982aedfd N	399	ino_t_to_u32(exp->ex_dentry->d_inode->i_ino);
1da177e4 LT	400	fhp->fh_handle.ofh_dirino = ino_t_to_u32(parent_ino(dentry));
	401	if (inode)
	402	_fh_update_old(dentry, exp, &fhp->fh_handle);
	403	} else {
	404	int len;
	405	fhp->fh_handle.fh_version = 1;
	406	fhp->fh_handle.fh_auth_type = 0;
	407	datap = fhp->fh_handle.fh_auth+0;
982aedfd	408	fhp->fh_handle.fh_fsid_type = fsid_type;
af6a4e28 N	409	mk_fsid(fsid_type, datap, ex_dev,
	410	exp->ex_dentry->d_inode->i_ino,
	411	exp->ex_fsid, exp->ex_uuid);
	412
982aedfd	413	len = key_len(fsid_type);
1da177e4 LT	414	datap += len/4;
	415	fhp->fh_handle.fh_size = 4 + len;
	416
	417	if (inode) {
	418	int size = (fhp->fh_maxsize-len-4)/4;
	419	fhp->fh_handle.fh_fileid_type =
	420	_fh_update(dentry, exp, datap, &size);
	421	fhp->fh_handle.fh_size += size*4;
	422	}
	423	if (fhp->fh_handle.fh_fileid_type == 255)
	424	return nfserr_opnotsupp;
	425	}
	426
	427	nfsd_nr_verified++;
	428	return 0;
	429	}
	430
	431	/*
	432	* Update file handle information after changing a dentry.
	433	* This is only called by nfsd_create, nfsd_create_v3 and nfsd_proc_create
	434	*/
83b11340	435	__be32
1da177e4 LT	436	fh_update(struct svc_fh *fhp)
	437	{
	438	struct dentry *dentry;
	439	__u32 *datap;
982aedfd	440
1da177e4 LT	441	if (!fhp->fh_dentry)
	442	goto out_bad;
	443
	444	dentry = fhp->fh_dentry;
	445	if (!dentry->d_inode)
	446	goto out_negative;
	447	if (fhp->fh_handle.fh_version != 1) {
	448	_fh_update_old(dentry, fhp->fh_export, &fhp->fh_handle);
	449	} else {
	450	int size;
	451	if (fhp->fh_handle.fh_fileid_type != 0)
4c9608b2	452	goto out;
1da177e4 LT	453	datap = fhp->fh_handle.fh_auth+
	454	fhp->fh_handle.fh_size/4 -1;
	455	size = (fhp->fh_maxsize - fhp->fh_handle.fh_size)/4;
	456	fhp->fh_handle.fh_fileid_type =
	457	_fh_update(dentry, fhp->fh_export, datap, &size);
	458	fhp->fh_handle.fh_size += size*4;
	459	if (fhp->fh_handle.fh_fileid_type == 255)
	460	return nfserr_opnotsupp;
	461	}
	462	out:
	463	return 0;
	464
	465	out_bad:
	466	printk(KERN_ERR "fh_update: fh not verified!\n");
	467	goto out;
	468	out_negative:
	469	printk(KERN_ERR "fh_update: %s/%s still negative!\n",
	470	dentry->d_parent->d_name.name, dentry->d_name.name);
	471	goto out;
1da177e4 LT	472	}
	473
	474	/*
	475	* Release a file handle.
	476	*/
	477	void
	478	fh_put(struct svc_fh *fhp)
	479	{
	480	struct dentry * dentry = fhp->fh_dentry;
	481	struct svc_export * exp = fhp->fh_export;
	482	if (dentry) {
	483	fh_unlock(fhp);
	484	fhp->fh_dentry = NULL;
	485	dput(dentry);
	486	#ifdef CONFIG_NFSD_V3
	487	fhp->fh_pre_saved = 0;
	488	fhp->fh_post_saved = 0;
	489	#endif
	490	nfsd_nr_put++;
	491	}
	492	if (exp) {
baab935f	493	cache_put(&exp->h, &svc_export_cache);
1da177e4 LT	494	fhp->fh_export = NULL;
	495	}
	496	return;
	497	}
	498
	499	/*
	500	* Shorthand for dprintk()'s
	501	*/
	502	char * SVCFH_fmt(struct svc_fh *fhp)
	503	{
	504	struct knfsd_fh *fh = &fhp->fh_handle;
	505
	506	static char buf[80];
	507	sprintf(buf, "%d: %08x %08x %08x %08x %08x %08x",
	508	fh->fh_size,
	509	fh->fh_base.fh_pad[0],
	510	fh->fh_base.fh_pad[1],
	511	fh->fh_base.fh_pad[2],
	512	fh->fh_base.fh_pad[3],
	513	fh->fh_base.fh_pad[4],
	514	fh->fh_base.fh_pad[5]);
	515	return buf;
	516	}
af6a4e28 N	517
	518	enum fsid_source fsid_source(struct svc_fh *fhp)
	519	{
	520	if (fhp->fh_handle.fh_version != 1)
	521	return FSIDSOURCE_DEV;
	522	switch(fhp->fh_handle.fh_fsid_type) {
	523	case FSID_DEV:
	524	case FSID_ENCODE_DEV:
	525	case FSID_MAJOR_MINOR:
	526	return FSIDSOURCE_DEV;
	527	case FSID_NUM:
	528	return FSIDSOURCE_FSID;
	529	default:
	530	if (fhp->fh_export->ex_flags & NFSEXP_FSID)
	531	return FSIDSOURCE_FSID;
	532	else
	533	return FSIDSOURCE_UUID;
	534	}
	535	}