[deliverable/linux.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/fs.h>
#include <linux/unistd.h>
#include <linux/string.h>
#include <linux/stat.h>
#include <linux/dcache.h>
#include <linux/exportfs.h>
#include <linux/mount.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;

/*
 * 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_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 = rqst_exp_find(rqstp, fh->fh_fsid_type, datap);
			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 = rqst_exp_find(rqstp, FSID_DEV, tfh);
		}

		error = nfserr_stale;
		if (PTR_ERR(exp) == -ENOENT)
			goto out;

		if (IS_ERR(exp)) {
			error = nfserrno(PTR_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 {
			dentry = exportfs_decode_fh(exp->ex_mnt, 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)
{
	if (dentry == exp->ex_dentry) {
		*maxsize = 0;
		return 0;
	}

	return exportfs_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;
	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.
	 */
 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;

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

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

		/* Need to check that this type works for this
		 * export point.  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.
		 */
		switch(fsid_type) {
		case FSID_DEV:
			if (!old_valid_dev(ex_dev))
				goto retry;
			/* FALL THROUGH */
		case FSID_MAJOR_MINOR:
		case FSID_ENCODE_DEV:
			if (!(exp->ex_dentry->d_inode->i_sb->s_type->fs_flags
			      & FS_REQUIRES_DEV))
				goto retry;
			break;
		case FSID_NUM:
			if (! (exp->ex_flags & NFSEXP_FSID))
				goto retry;
			break;
		case FSID_UUID8:
		case FSID_UUID16:
			if (!root_export)
				goto retry;
			/* fall through */
		case FSID_UUID4_INUM:
		case FSID_UUID16_INUM:
			if (exp->ex_uuid == NULL)
				goto retry;
			break;
		}
	} 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	12	#include <linux/slab.h>
1da177e4 LT	13	#include <linux/fs.h>
	14	#include <linux/unistd.h>
	15	#include <linux/string.h>
	16	#include <linux/stat.h>
	17	#include <linux/dcache.h>
a5694255	18	#include <linux/exportfs.h>
1da177e4	19	#include <linux/mount.h>
1da177e4	20
ad06e4bd	21	#include <linux/sunrpc/clnt.h>
1da177e4 LT	22	#include <linux/sunrpc/svc.h>
	23	#include <linux/nfsd/nfsd.h>
	24
	25	#define NFSDDBG_FACILITY NFSDDBG_FH
1da177e4 LT	26
	27
	28	static int nfsd_nr_verified;
	29	static int nfsd_nr_put;
	30
1da177e4 LT	31	/*
	32	* our acceptability function.
	33	* if NOSUBTREECHECK, accept anything
	34	* if not, require that we can walk up to exp->ex_dentry
	35	* doing some checks on the 'x' bits
	36	*/
	37	static int nfsd_acceptable(void expv, struct dentry dentry)
	38	{
	39	struct svc_export *exp = expv;
	40	int rv;
	41	struct dentry *tdentry;
	42	struct dentry *parent;
	43
	44	if (exp->ex_flags & NFSEXP_NOSUBTREECHECK)
	45	return 1;
	46
	47	tdentry = dget(dentry);
	48	while (tdentry != exp->ex_dentry && ! IS_ROOT(tdentry)) {
	49	/* make sure parents give x permission to user */
	50	int err;
	51	parent = dget_parent(tdentry);
	52	err = permission(parent->d_inode, MAY_EXEC, NULL);
	53	if (err < 0) {
	54	dput(parent);
	55	break;
	56	}
	57	dput(tdentry);
	58	tdentry = parent;
	59	}
	60	if (tdentry != exp->ex_dentry)
	61	dprintk("nfsd_acceptable failed at %p %s\n", tdentry, tdentry->d_name.name);
	62	rv = (tdentry == exp->ex_dentry);
	63	dput(tdentry);
	64	return rv;
	65	}
	66
	67	/* Type check. The correct error return for type mismatches does not seem to be
	68	* generally agreed upon. SunOS seems to use EISDIR if file isn't S_IFREG; a
	69	* comment in the NFSv3 spec says this is incorrect (implementation notes for
	70	* the write call).
	71	*/
83b11340	72	static inline __be32
1da177e4 LT	73	nfsd_mode_check(struct svc_rqst *rqstp, umode_t mode, int type)
	74	{
	75	/* Type can be negative when creating hardlinks - not to a dir */
	76	if (type > 0 && (mode & S_IFMT) != type) {
	77	if (rqstp->rq_vers == 4 && (mode & S_IFMT) == S_IFLNK)
	78	return nfserr_symlink;
	79	else if (type == S_IFDIR)
	80	return nfserr_notdir;
	81	else if ((mode & S_IFMT) == S_IFDIR)
	82	return nfserr_isdir;
	83	else
	84	return nfserr_inval;
	85	}
	86	if (type < 0 && (mode & S_IFMT) == -type) {
	87	if (rqstp->rq_vers == 4 && (mode & S_IFMT) == S_IFLNK)
	88	return nfserr_symlink;
	89	else if (type == -S_IFDIR)
	90	return nfserr_isdir;
	91	else
	92	return nfserr_notdir;
	93	}
	94	return 0;
	95	}
	96
	97	/*
	98	* Perform sanity checks on the dentry in a client's file handle.
	99	*
	100	* Note that the file handle dentry may need to be freed even after
	101	* an error return.
	102	*
	103	* This is only called at the start of an nfsproc call, so fhp points to
	104	* a svc_fh which is all 0 except for the over-the-wire file handle.
	105	*/
83b11340	106	__be32
1da177e4 LT	107	fh_verify(struct svc_rqst rqstp, struct svc_fh fhp, int type, int access)
	108	{
	109	struct knfsd_fh *fh = &fhp->fh_handle;
	110	struct svc_export *exp = NULL;
	111	struct dentry *dentry;
83b11340	112	__be32 error = 0;
1da177e4 LT	113
	114	dprintk("nfsd: fh_verify(%s)\n", SVCFH_fmt(fhp));
	115
1da177e4 LT	116	if (!fhp->fh_dentry) {
	117	__u32 *datap=NULL;
	118	__u32 tfh[3]; /* filehandle fragment for oldstyle filehandles */
	119	int fileid_type;
	120	int data_left = fh->fh_size/4;
	121
	122	error = nfserr_stale;
1da177e4 LT	123	if (rqstp->rq_vers > 2)
	124	error = nfserr_badhandle;
	125	if (rqstp->rq_vers == 4 && fh->fh_size == 0)
	126	return nfserr_nofilehandle;
	127
	128	if (fh->fh_version == 1) {
	129	int len;
	130	datap = fh->fh_auth;
	131	if (--data_left<0) goto out;
	132	switch (fh->fh_auth_type) {
	133	case 0: break;
	134	default: goto out;
	135	}
	136	len = key_len(fh->fh_fsid_type) / 4;
	137	if (len == 0) goto out;
af6a4e28	138	if (fh->fh_fsid_type == FSID_MAJOR_MINOR) {
1da177e4	139	/* deprecated, convert to type 3 */
af6a4e28 N	140	len = key_len(FSID_ENCODE_DEV)/4;
af6a4e28 N	141	fh->fh_fsid_type = FSID_ENCODE_DEV;
1da177e4 LT	142	fh->fh_fsid[0] = new_encode_dev(MKDEV(ntohl(fh->fh_fsid[0]), ntohl(fh->fh_fsid[1])));
	143	fh->fh_fsid[1] = fh->fh_fsid[2];
	144	}
	145	if ((data_left -= len)<0) goto out;
0989a788	146	exp = rqst_exp_find(rqstp, fh->fh_fsid_type, datap);
1da177e4 LT	147	datap += len;
	148	} else {
	149	dev_t xdev;
	150	ino_t xino;
	151	if (fh->fh_size != NFS_FHSIZE)
	152	goto out;
	153	/* assume old filehandle format */
	154	xdev = old_decode_dev(fh->ofh_xdev);
	155	xino = u32_to_ino_t(fh->ofh_xino);
af6a4e28	156	mk_fsid(FSID_DEV, tfh, xdev, xino, 0, NULL);
0989a788	157	exp = rqst_exp_find(rqstp, FSID_DEV, tfh);
1da177e4 LT	158	}
1da177e4 LT	159
2d3bb252 BF	160	error = nfserr_stale;
2d3bb252 BF	161	if (PTR_ERR(exp) == -ENOENT)
1da177e4 LT	162	goto out;
1da177e4 LT	163
2d3bb252 BF	164	if (IS_ERR(exp)) {
2d3bb252 BF	165	error = nfserrno(PTR_ERR(exp));
1da177e4	166	goto out;
2d3bb252	167	}
1da177e4 LT	168
	169	/* Check if the request originated from a secure port. */
	170	error = nfserr_perm;
	171	if (!rqstp->rq_secure && EX_SECURE(exp)) {
ad06e4bd	172	char buf[RPC_MAX_ADDRBUFLEN];
1da177e4	173	printk(KERN_WARNING
ad06e4bd CL	174	"nfsd: request from insecure port %s!\n",
ad06e4bd CL	175	svc_print_addr(rqstp, buf, sizeof(buf)));
1da177e4 LT	176	goto out;
	177	}
	178
d1bbf14f N	179	/* Set user creds for this exportpoint */
	180	error = nfserrno(nfsd_setuser(rqstp, exp));
	181	if (error)
	182	goto out;
	183
1da177e4 LT	184	/*
	185	* Look up the dentry using the NFS file handle.
	186	*/
	187	error = nfserr_stale;
	188	if (rqstp->rq_vers > 2)
	189	error = nfserr_badhandle;
	190
	191	if (fh->fh_version != 1) {
	192	tfh[0] = fh->ofh_ino;
	193	tfh[1] = fh->ofh_generation;
	194	tfh[2] = fh->ofh_dirino;
	195	datap = tfh;
	196	data_left = 3;
	197	if (fh->ofh_dirino == 0)
	198	fileid_type = 1;
	199	else
	200	fileid_type = 2;
	201	} else
	202	fileid_type = fh->fh_fileid_type;
982aedfd	203
1da177e4 LT	204	if (fileid_type == 0)
	205	dentry = dget(exp->ex_dentry);
	206	else {
d37065cd CH	207	dentry = exportfs_decode_fh(exp->ex_mnt, datap,
	208	data_left, fileid_type,
	209	nfsd_acceptable, exp);
1da177e4 LT	210	}
	211	if (dentry == NULL)
	212	goto out;
	213	if (IS_ERR(dentry)) {
	214	if (PTR_ERR(dentry) != -EINVAL)
	215	error = nfserrno(PTR_ERR(dentry));
	216	goto out;
	217	}
34e9a63b	218
1da177e4 LT	219	if (S_ISDIR(dentry->d_inode->i_mode) &&
	220	(dentry->d_flags & DCACHE_DISCONNECTED)) {
	221	printk("nfsd: find_fh_dentry returned a DISCONNECTED directory: %s/%s\n",
	222	dentry->d_parent->d_name.name, dentry->d_name.name);
	223	}
1da177e4 LT	224
	225	fhp->fh_dentry = dentry;
	226	fhp->fh_export = exp;
	227	nfsd_nr_verified++;
	228	} else {
	229	/* just rechecking permissions
	230	* (e.g. nfsproc_create calls fh_verify, then nfsd_create does as well)
	231	*/
	232	dprintk("nfsd: fh_verify - just checking\n");
	233	dentry = fhp->fh_dentry;
	234	exp = fhp->fh_export;
d1bbf14f N	235	/* Set user creds for this exportpoint; necessary even
	236	* in the "just checking" case because this may be a
	237	* filehandle that was created by fh_compose, and that
	238	* is about to be used in another nfsv4 compound
	239	* operation */
	240	error = nfserrno(nfsd_setuser(rqstp, exp));
	241	if (error)
	242	goto out;
1da177e4 LT	243	}
	244	cache_get(&exp->h);
	245
7fc90ec9	246
1da177e4 LT	247	error = nfsd_mode_check(rqstp, dentry->d_inode->i_mode, type);
	248	if (error)
	249	goto out;
	250
	251	/* Finally, check access permissions. */
	252	error = nfsd_permission(exp, dentry, access);
	253
1da177e4	254	if (error) {
34e9a63b N	255	dprintk("fh_verify: %s/%s permission failure, "
	256	"acc=%x, error=%d\n",
	257	dentry->d_parent->d_name.name,
	258	dentry->d_name.name,
fc2dd2e5	259	access, ntohl(error));
1da177e4	260	}
1da177e4 LT	261	out:
	262	if (exp && !IS_ERR(exp))
	263	exp_put(exp);
	264	if (error == nfserr_stale)
	265	nfsdstats.fh_stale++;
	266	return error;
	267	}
	268
	269
	270	/*
	271	* Compose a file handle for an NFS reply.
	272	*
	273	* Note that when first composed, the dentry may not yet have
	274	* an inode. In this case a call to fh_update should be made
	275	* before the fh goes out on the wire ...
	276	*/
	277	static inline int _fh_update(struct dentry dentry, struct svc_export exp,
	278	__u32 datap, int maxsize)
	279	{
1da177e4 LT	280	if (dentry == exp->ex_dentry) {
	281	*maxsize = 0;
	282	return 0;
	283	}
	284
d37065cd CH	285	return exportfs_encode_fh(dentry, datap, maxsize,
d37065cd CH	286	!(exp->ex_flags & NFSEXP_NOSUBTREECHECK));
1da177e4 LT	287	}
	288
	289	/*
	290	* for composing old style file handles
	291	*/
	292	static inline void _fh_update_old(struct dentry *dentry,
	293	struct svc_export *exp,
	294	struct knfsd_fh *fh)
	295	{
	296	fh->ofh_ino = ino_t_to_u32(dentry->d_inode->i_ino);
	297	fh->ofh_generation = dentry->d_inode->i_generation;
	298	if (S_ISDIR(dentry->d_inode->i_mode) \|\|
	299	(exp->ex_flags & NFSEXP_NOSUBTREECHECK))
	300	fh->ofh_dirino = 0;
	301	}
	302
83b11340	303	__be32
982aedfd N	304	fh_compose(struct svc_fh fhp, struct svc_export exp, struct dentry *dentry,
982aedfd N	305	struct svc_fh *ref_fh)
1da177e4 LT	306	{
1da177e4 LT	307	/* ref_fh is a reference file handle.
7e405364 N	308	* if it is non-null and for the same filesystem, then we should compose
7e405364 N	309	* a filehandle which is of the same version, where possible.
1da177e4 LT	310	* Currently, that means that if ref_fh->fh_handle.fh_version == 0xca
	311	* Then create a 32byte filehandle using nfs_fhbase_old
	312	*
	313	*/
	314
b41eeef1	315	u8 version;
982aedfd	316	u8 fsid_type = 0;
1da177e4 LT	317	struct inode * inode = dentry->d_inode;
	318	struct dentry *parent = dentry->d_parent;
	319	__u32 *datap;
	320	dev_t ex_dev = exp->ex_dentry->d_inode->i_sb->s_dev;
af6a4e28	321	int root_export = (exp->ex_dentry == exp->ex_dentry->d_sb->s_root);
1da177e4 LT	322
	323	dprintk("nfsd: fh_compose(exp %02x:%02x/%ld %s/%s, ino=%ld)\n",
	324	MAJOR(ex_dev), MINOR(ex_dev),
	325	(long) exp->ex_dentry->d_inode->i_ino,
	326	parent->d_name.name, dentry->d_name.name,
	327	(inode ? inode->i_ino : 0));
	328
982aedfd N	329	/* Choose filehandle version and fsid type based on
	330	* the reference filehandle (if it is in the same export)
	331	* or the export options.
	332	*/
b41eeef1 N	333	retry:
b41eeef1 N	334	version = 1;
7e405364	335	if (ref_fh && ref_fh->fh_export == exp) {
982aedfd	336	version = ref_fh->fh_handle.fh_version;
b41eeef1 N	337	fsid_type = ref_fh->fh_handle.fh_fsid_type;
	338
	339	if (ref_fh == fhp)
	340	fh_put(ref_fh);
	341	ref_fh = NULL;
	342
	343	switch (version) {
	344	case 0xca:
af6a4e28	345	fsid_type = FSID_DEV;
b41eeef1 N	346	break;
	347	case 1:
	348	break;
	349	default:
	350	goto retry;
	351	}
	352
	353	/* Need to check that this type works for this
	354	* export point. As the fsid -> filesystem mapping
	355	* was guided by user-space, there is no guarantee
	356	* that the filesystem actually supports that fsid
	357	* type. If it doesn't we loop around again without
	358	* ref_fh set.
982aedfd	359	*/
b41eeef1 N	360	switch(fsid_type) {
	361	case FSID_DEV:
	362	if (!old_valid_dev(ex_dev))
	363	goto retry;
	364	/* FALL THROUGH */
	365	case FSID_MAJOR_MINOR:
	366	case FSID_ENCODE_DEV:
	367	if (!(exp->ex_dentry->d_inode->i_sb->s_type->fs_flags
	368	& FS_REQUIRES_DEV))
	369	goto retry;
	370	break;
	371	case FSID_NUM:
	372	if (! (exp->ex_flags & NFSEXP_FSID))
	373	goto retry;
	374	break;
	375	case FSID_UUID8:
	376	case FSID_UUID16:
	377	if (!root_export)
	378	goto retry;
	379	/* fall through */
	380	case FSID_UUID4_INUM:
	381	case FSID_UUID16_INUM:
	382	if (exp->ex_uuid == NULL)
	383	goto retry;
	384	break;
	385	}
af6a4e28 N	386	} else if (exp->ex_uuid) {
	387	if (fhp->fh_maxsize >= 64) {
	388	if (root_export)
	389	fsid_type = FSID_UUID16;
	390	else
	391	fsid_type = FSID_UUID16_INUM;
	392	} else {
	393	if (root_export)
	394	fsid_type = FSID_UUID8;
	395	else
	396	fsid_type = FSID_UUID4_INUM;
	397	}
1da177e4	398	} else if (exp->ex_flags & NFSEXP_FSID)
af6a4e28	399	fsid_type = FSID_NUM;
982aedfd	400	else if (!old_valid_dev(ex_dev))
1da177e4	401	/* for newer device numbers, we must use a newer fsid format */
af6a4e28	402	fsid_type = FSID_ENCODE_DEV;
982aedfd	403	else
af6a4e28	404	fsid_type = FSID_DEV;
1da177e4 LT	405
	406	if (ref_fh == fhp)
	407	fh_put(ref_fh);
	408
	409	if (fhp->fh_locked \|\| fhp->fh_dentry) {
	410	printk(KERN_ERR "fh_compose: fh %s/%s not initialized!\n",
982aedfd	411	parent->d_name.name, dentry->d_name.name);
1da177e4 LT	412	}
	413	if (fhp->fh_maxsize < NFS_FHSIZE)
	414	printk(KERN_ERR "fh_compose: called with maxsize %d! %s/%s\n",
982aedfd N	415	fhp->fh_maxsize,
982aedfd N	416	parent->d_name.name, dentry->d_name.name);
1da177e4 LT	417
	418	fhp->fh_dentry = dget(dentry); /* our internal copy */
	419	fhp->fh_export = exp;
	420	cache_get(&exp->h);
	421
982aedfd	422	if (version == 0xca) {
1da177e4 LT	423	/* old style filehandle please */
	424	memset(&fhp->fh_handle.fh_base, 0, NFS_FHSIZE);
	425	fhp->fh_handle.fh_size = NFS_FHSIZE;
	426	fhp->fh_handle.ofh_dcookie = 0xfeebbaca;
	427	fhp->fh_handle.ofh_dev = old_encode_dev(ex_dev);
	428	fhp->fh_handle.ofh_xdev = fhp->fh_handle.ofh_dev;
982aedfd N	429	fhp->fh_handle.ofh_xino =
982aedfd N	430	ino_t_to_u32(exp->ex_dentry->d_inode->i_ino);
1da177e4 LT	431	fhp->fh_handle.ofh_dirino = ino_t_to_u32(parent_ino(dentry));
	432	if (inode)
	433	_fh_update_old(dentry, exp, &fhp->fh_handle);
	434	} else {
	435	int len;
	436	fhp->fh_handle.fh_version = 1;
	437	fhp->fh_handle.fh_auth_type = 0;
	438	datap = fhp->fh_handle.fh_auth+0;
982aedfd	439	fhp->fh_handle.fh_fsid_type = fsid_type;
af6a4e28 N	440	mk_fsid(fsid_type, datap, ex_dev,
	441	exp->ex_dentry->d_inode->i_ino,
	442	exp->ex_fsid, exp->ex_uuid);
	443
982aedfd	444	len = key_len(fsid_type);
1da177e4 LT	445	datap += len/4;
	446	fhp->fh_handle.fh_size = 4 + len;
	447
	448	if (inode) {
	449	int size = (fhp->fh_maxsize-len-4)/4;
	450	fhp->fh_handle.fh_fileid_type =
	451	_fh_update(dentry, exp, datap, &size);
	452	fhp->fh_handle.fh_size += size*4;
	453	}
	454	if (fhp->fh_handle.fh_fileid_type == 255)
	455	return nfserr_opnotsupp;
	456	}
	457
	458	nfsd_nr_verified++;
	459	return 0;
	460	}
	461
	462	/*
	463	* Update file handle information after changing a dentry.
	464	* This is only called by nfsd_create, nfsd_create_v3 and nfsd_proc_create
	465	*/
83b11340	466	__be32
1da177e4 LT	467	fh_update(struct svc_fh *fhp)
	468	{
	469	struct dentry *dentry;
	470	__u32 *datap;
982aedfd	471
1da177e4 LT	472	if (!fhp->fh_dentry)
	473	goto out_bad;
	474
	475	dentry = fhp->fh_dentry;
	476	if (!dentry->d_inode)
	477	goto out_negative;
	478	if (fhp->fh_handle.fh_version != 1) {
	479	_fh_update_old(dentry, fhp->fh_export, &fhp->fh_handle);
	480	} else {
	481	int size;
	482	if (fhp->fh_handle.fh_fileid_type != 0)
4c9608b2	483	goto out;
1da177e4 LT	484	datap = fhp->fh_handle.fh_auth+
	485	fhp->fh_handle.fh_size/4 -1;
	486	size = (fhp->fh_maxsize - fhp->fh_handle.fh_size)/4;
	487	fhp->fh_handle.fh_fileid_type =
	488	_fh_update(dentry, fhp->fh_export, datap, &size);
	489	fhp->fh_handle.fh_size += size*4;
	490	if (fhp->fh_handle.fh_fileid_type == 255)
	491	return nfserr_opnotsupp;
	492	}
	493	out:
	494	return 0;
	495
	496	out_bad:
	497	printk(KERN_ERR "fh_update: fh not verified!\n");
	498	goto out;
	499	out_negative:
	500	printk(KERN_ERR "fh_update: %s/%s still negative!\n",
	501	dentry->d_parent->d_name.name, dentry->d_name.name);
	502	goto out;
1da177e4 LT	503	}
	504
	505	/*
	506	* Release a file handle.
	507	*/
	508	void
	509	fh_put(struct svc_fh *fhp)
	510	{
	511	struct dentry * dentry = fhp->fh_dentry;
	512	struct svc_export * exp = fhp->fh_export;
	513	if (dentry) {
	514	fh_unlock(fhp);
	515	fhp->fh_dentry = NULL;
	516	dput(dentry);
	517	#ifdef CONFIG_NFSD_V3
	518	fhp->fh_pre_saved = 0;
	519	fhp->fh_post_saved = 0;
	520	#endif
	521	nfsd_nr_put++;
	522	}
	523	if (exp) {
baab935f	524	cache_put(&exp->h, &svc_export_cache);
1da177e4 LT	525	fhp->fh_export = NULL;
	526	}
	527	return;
	528	}
	529
	530	/*
	531	* Shorthand for dprintk()'s
	532	*/
	533	char * SVCFH_fmt(struct svc_fh *fhp)
	534	{
	535	struct knfsd_fh *fh = &fhp->fh_handle;
	536
	537	static char buf[80];
	538	sprintf(buf, "%d: %08x %08x %08x %08x %08x %08x",
	539	fh->fh_size,
	540	fh->fh_base.fh_pad[0],
	541	fh->fh_base.fh_pad[1],
	542	fh->fh_base.fh_pad[2],
	543	fh->fh_base.fh_pad[3],
	544	fh->fh_base.fh_pad[4],
	545	fh->fh_base.fh_pad[5]);
	546	return buf;
	547	}
af6a4e28 N	548
	549	enum fsid_source fsid_source(struct svc_fh *fhp)
	550	{
	551	if (fhp->fh_handle.fh_version != 1)
	552	return FSIDSOURCE_DEV;
	553	switch(fhp->fh_handle.fh_fsid_type) {
	554	case FSID_DEV:
	555	case FSID_ENCODE_DEV:
	556	case FSID_MAJOR_MINOR:
	557	return FSIDSOURCE_DEV;
	558	case FSID_NUM:
	559	return FSIDSOURCE_FSID;
	560	default:
	561	if (fhp->fh_export->ex_flags & NFSEXP_FSID)
	562	return FSIDSOURCE_FSID;
	563	else
	564	return FSIDSOURCE_UUID;
	565	}
	566	}