include/linux/nfsd/nfsfh.h - kernel/msm-4.9 - Gitiles

 /*
  * include/linux/nfsd/nfsfh.h
  *
  * This file describes the layout of the file handles as passed
  * over the wire.
  *
  * Earlier versions of knfsd used to sign file handles using keyed MD5
  * or SHA. I've removed this code, because it doesn't give you more
  * security than blocking external access to port 2049 on your firewall.
  *
  * Copyright (C) 1995, 1996, 1997 Olaf Kirch <okir@monad.swb.de>
  */

 #ifndef _LINUX_NFSD_FH_H
 #define _LINUX_NFSD_FH_H

 #include <asm/types.h>
 #ifdef __KERNEL__
 # include <linux/types.h>
 # include <linux/string.h>
 # include <linux/fs.h>
 #endif
 #include <linux/nfsd/const.h>
 #include <linux/nfsd/debug.h>

 /*
  * This is the old "dentry style" Linux NFSv2 file handle.
  *
  * The xino and xdev fields are currently used to transport the
  * ino/dev of the exported inode.
  */
 struct nfs_fhbase_old {
 	__u32		fb_dcookie;	/* dentry cookie - always 0xfeebbaca */
 	__u32		fb_ino;		/* our inode number */
 	__u32		fb_dirino;	/* dir inode number, 0 for directories */
 	__u32		fb_dev;		/* our device */
 	__u32		fb_xdev;
 	__u32		fb_xino;
 	__u32		fb_generation;
 };

 /*
  * This is the new flexible, extensible style NFSv2/v3 file handle.
  * by Neil Brown <neilb@cse.unsw.edu.au> - March 2000
  *
  * The file handle is seens as a list of 4byte words.
  * The first word contains a version number (1) and four descriptor bytes
  * that tell how the remaining 3 variable length fields should be handled.
  * These three bytes are auth_type, fsid_type and fileid_type.
  *
  * All 4byte values are in host-byte-order.
  *
  * The auth_type field specifies how the filehandle can be authenticated
  * This might allow a file to be confirmed to be in a writable part of a
  * filetree without checking the path from it upto the root.
  * Current values:
  *     0  - No authentication.  fb_auth is 0 bytes long
  * Possible future values:
  *     1  - 4 bytes taken from MD5 hash of the remainer of the file handle
  *          prefixed by a secret and with the important export flags.
  *
  * The fsid_type identifies how the filesystem (or export point) is
  *    encoded.
  *  Current values:
  *     0  - 4 byte device id (ms-2-bytes major, ls-2-bytes minor), 4byte inode number
  *        NOTE: we cannot use the kdev_t device id value, because kdev_t.h
  *              says we mustn't.  We must break it up and reassemble.
  *     1  - 4 byte user specified identifier
  *     2  - 4 byte major, 4 byte minor, 4 byte inode number - DEPRECATED
  *     3  - 4 byte device id, encoded for user-space, 4 byte inode number
  *
  * The fileid_type identified how the file within the filesystem is encoded.
  * This is (will be) passed to, and set by, the underlying filesystem if it supports
  * filehandle operations.  The filesystem must not use the value '0' or '0xff' and may
  * only use the values 1 and 2 as defined below:
  *  Current values:
  *    0   - The root, or export point, of the filesystem.  fb_fileid is 0 bytes.
  *    1   - 32bit inode number, 32 bit generation number.
  *    2   - 32bit inode number, 32 bit generation number, 32 bit parent directory inode number.
  *
  */
 struct nfs_fhbase_new {
 	__u8		fb_version;	/* == 1, even => nfs_fhbase_old */
 	__u8		fb_auth_type;
 	__u8		fb_fsid_type;
 	__u8		fb_fileid_type;
 	__u32		fb_auth[1];
 /*	__u32		fb_fsid[0]; floating */
 /*	__u32		fb_fileid[0]; floating */
 };

 struct knfsd_fh {
 	unsigned int	fh_size;	/* significant for NFSv3.
 					 * Points to the current size while building
 					 * a new file handle
 					 */
 	union {
 		struct nfs_fhbase_old	fh_old;
 		__u32			fh_pad[NFS4_FHSIZE/4];
 		struct nfs_fhbase_new	fh_new;
 	} fh_base;
 };

 #define ofh_dcookie		fh_base.fh_old.fb_dcookie
 #define ofh_ino			fh_base.fh_old.fb_ino
 #define ofh_dirino		fh_base.fh_old.fb_dirino
 #define ofh_dev			fh_base.fh_old.fb_dev
 #define ofh_xdev		fh_base.fh_old.fb_xdev
 #define ofh_xino		fh_base.fh_old.fb_xino
 #define ofh_generation		fh_base.fh_old.fb_generation

 #define	fh_version		fh_base.fh_new.fb_version
 #define	fh_fsid_type		fh_base.fh_new.fb_fsid_type
 #define	fh_auth_type		fh_base.fh_new.fb_auth_type
 #define	fh_fileid_type		fh_base.fh_new.fb_fileid_type
 #define	fh_auth			fh_base.fh_new.fb_auth
 #define	fh_fsid			fh_base.fh_new.fb_auth

 #ifdef __KERNEL__

 static inline __u32 ino_t_to_u32(ino_t ino)
 {
 	return (__u32) ino;
 }

 static inline ino_t u32_to_ino_t(__u32 uino)
 {
 	return (ino_t) uino;
 }

 /*
  * This is the internal representation of an NFS handle used in knfsd.
  * pre_mtime/post_version will be used to support wcc_attr's in NFSv3.
  */
 typedef struct svc_fh {
 	struct knfsd_fh		fh_handle;	/* FH data */
 	struct dentry *		fh_dentry;	/* validated dentry */
 	struct svc_export *	fh_export;	/* export pointer */
 	int			fh_maxsize;	/* max size for fh_handle */

 	unsigned char		fh_locked;	/* inode locked by us */

 #ifdef CONFIG_NFSD_V3
 	unsigned char		fh_post_saved;	/* post-op attrs saved */
 	unsigned char		fh_pre_saved;	/* pre-op attrs saved */

 	/* Pre-op attributes saved during fh_lock */
 	__u64			fh_pre_size;	/* size before operation */
 	struct timespec		fh_pre_mtime;	/* mtime before oper */
 	struct timespec		fh_pre_ctime;	/* ctime before oper */

 	/* Post-op attributes saved in fh_unlock */
 	struct kstat		fh_post_attr;	/* full attrs after operation */
 #endif /* CONFIG_NFSD_V3 */

 } svc_fh;

 enum nfsd_fsid {
 	FSID_DEV = 0,
 	FSID_NUM,
 	FSID_MAJOR_MINOR,
 	FSID_ENCODE_DEV,
 	FSID_UUID4_INUM,
 	FSID_UUID8,
 	FSID_UUID16,
 	FSID_UUID16_INUM,
 };

 enum fsid_source {
 	FSIDSOURCE_DEV,
 	FSIDSOURCE_FSID,
 	FSIDSOURCE_UUID,
 };
 extern enum fsid_source fsid_source(struct svc_fh *fhp);


 /* This might look a little large to "inline" but in all calls except
  * one, 'vers' is constant so moste of the function disappears.
  */
 static inline void mk_fsid(int vers, u32 *fsidv, dev_t dev, ino_t ino,
 			   u32 fsid, unsigned char *uuid)
 {
 	u32 *up;
 	switch(vers) {
 	case FSID_DEV:
 		fsidv[0] = htonl((MAJOR(dev)<<16) |
 				 MINOR(dev));
 		fsidv[1] = ino_t_to_u32(ino);
 		break;
 	case FSID_NUM:
 		fsidv[0] = fsid;
 		break;
 	case FSID_MAJOR_MINOR:
 		fsidv[0] = htonl(MAJOR(dev));
 		fsidv[1] = htonl(MINOR(dev));
 		fsidv[2] = ino_t_to_u32(ino);
 		break;

 	case FSID_ENCODE_DEV:
 		fsidv[0] = new_encode_dev(dev);
 		fsidv[1] = ino_t_to_u32(ino);
 		break;

 	case FSID_UUID4_INUM:
 		/* 4 byte fsid and inode number */
 		up = (u32*)uuid;
 		fsidv[0] = ino_t_to_u32(ino);
 		fsidv[1] = up[0] ^ up[1] ^ up[2] ^ up[3];
 		break;

 	case FSID_UUID8:
 		/* 8 byte fsid  */
 		up = (u32*)uuid;
 		fsidv[0] = up[0] ^ up[2];
 		fsidv[1] = up[1] ^ up[3];
 		break;

 	case FSID_UUID16:
 		/* 16 byte fsid - NFSv3+ only */
 		memcpy(fsidv, uuid, 16);
 		break;

 	case FSID_UUID16_INUM:
 		/* 8 byte inode and 16 byte fsid */
 		*(u64*)fsidv = (u64)ino;
 		memcpy(fsidv+2, uuid, 16);
 		break;
 	default: BUG();
 	}
 }

 static inline int key_len(int type)
 {
 	switch(type) {
 	case FSID_DEV:		return 8;
 	case FSID_NUM: 		return 4;
 	case FSID_MAJOR_MINOR:	return 12;
 	case FSID_ENCODE_DEV:	return 8;
 	case FSID_UUID4_INUM:	return 8;
 	case FSID_UUID8:	return 8;
 	case FSID_UUID16:	return 16;
 	case FSID_UUID16_INUM:	return 24;
 	default: return 0;
 	}
 }

 /*
  * Shorthand for dprintk()'s
  */
 extern char * SVCFH_fmt(struct svc_fh *fhp);

 /*
  * Function prototypes
  */
 __be32	fh_verify(struct svc_rqst *, struct svc_fh *, int, int);
 __be32	fh_compose(struct svc_fh *, struct svc_export *, struct dentry *, struct svc_fh *);
 __be32	fh_update(struct svc_fh *);
 void	fh_put(struct svc_fh *);

 static __inline__ struct svc_fh *
 fh_copy(struct svc_fh *dst, struct svc_fh *src)
 {
 	WARN_ON(src->fh_dentry || src->fh_locked);

 	*dst = *src;
 	return dst;
 }

 static __inline__ struct svc_fh *
 fh_init(struct svc_fh *fhp, int maxsize)
 {
 	memset(fhp, 0, sizeof(*fhp));
 	fhp->fh_maxsize = maxsize;
 	return fhp;
 }

 #ifdef CONFIG_NFSD_V3
 /*
  * Fill in the pre_op attr for the wcc data
  */
 static inline void
 fill_pre_wcc(struct svc_fh *fhp)
 {
 	struct inode    *inode;

 	inode = fhp->fh_dentry->d_inode;
 	if (!fhp->fh_pre_saved) {
 		fhp->fh_pre_mtime = inode->i_mtime;
 		fhp->fh_pre_ctime = inode->i_ctime;
 		fhp->fh_pre_size  = inode->i_size;
 		fhp->fh_pre_saved = 1;
 	}
 }

 extern void fill_post_wcc(struct svc_fh *);
 #else
 #define	fill_pre_wcc(ignored)
 #define fill_post_wcc(notused)
 #endif /* CONFIG_NFSD_V3 */


 /*
  * Lock a file handle/inode
  * NOTE: both fh_lock and fh_unlock are done "by hand" in
  * vfs.c:nfsd_rename as it needs to grab 2 i_mutex's at once
  * so, any changes here should be reflected there.
  */

 static inline void
 fh_lock_nested(struct svc_fh *fhp, unsigned int subclass)
 {
 	struct dentry	*dentry = fhp->fh_dentry;
 	struct inode	*inode;

 	dfprintk(FILEOP, "nfsd: fh_lock(%s) locked = %d\n",
 			SVCFH_fmt(fhp), fhp->fh_locked);

 	BUG_ON(!dentry);

 	if (fhp->fh_locked) {
 		printk(KERN_WARNING "fh_lock: %s/%s already locked!\n",
 			dentry->d_parent->d_name.name, dentry->d_name.name);
 		return;
 	}

 	inode = dentry->d_inode;
 	mutex_lock_nested(&inode->i_mutex, subclass);
 	fill_pre_wcc(fhp);
 	fhp->fh_locked = 1;
 }

 static inline void
 fh_lock(struct svc_fh *fhp)
 {
 	fh_lock_nested(fhp, I_MUTEX_NORMAL);
 }

 /*
  * Unlock a file handle/inode
  */
 static inline void
 fh_unlock(struct svc_fh *fhp)
 {
 	BUG_ON(!fhp->fh_dentry);

 	if (fhp->fh_locked) {
 		fill_post_wcc(fhp);
 		mutex_unlock(&fhp->fh_dentry->d_inode->i_mutex);
 		fhp->fh_locked = 0;
 	}
 }
 #endif /* __KERNEL__ */


 #endif /* _LINUX_NFSD_FH_H */
	/*
	* include/linux/nfsd/nfsfh.h
	*
	* This file describes the layout of the file handles as passed
	* over the wire.
	*
	* Earlier versions of knfsd used to sign file handles using keyed MD5
	* or SHA. I've removed this code, because it doesn't give you more
	* security than blocking external access to port 2049 on your firewall.
	*
	* Copyright (C) 1995, 1996, 1997 Olaf Kirch <okir@monad.swb.de>
	*/

	#ifndef _LINUX_NFSD_FH_H
	#define _LINUX_NFSD_FH_H

	#include <asm/types.h>
	#ifdef __KERNEL__
	# include <linux/types.h>
	# include <linux/string.h>
	# include <linux/fs.h>
	#endif
	#include <linux/nfsd/const.h>
	#include <linux/nfsd/debug.h>

	/*
	* This is the old "dentry style" Linux NFSv2 file handle.
	*
	* The xino and xdev fields are currently used to transport the
	* ino/dev of the exported inode.
	*/
	struct nfs_fhbase_old {
	__u32 fb_dcookie; /* dentry cookie - always 0xfeebbaca */
	__u32 fb_ino; /* our inode number */
	__u32 fb_dirino; /* dir inode number, 0 for directories */
	__u32 fb_dev; /* our device */
	__u32 fb_xdev;
	__u32 fb_xino;
	__u32 fb_generation;
	};

	/*
	* This is the new flexible, extensible style NFSv2/v3 file handle.
	* by Neil Brown <neilb@cse.unsw.edu.au> - March 2000
	*
	* The file handle is seens as a list of 4byte words.
	* The first word contains a version number (1) and four descriptor bytes
	* that tell how the remaining 3 variable length fields should be handled.
	* These three bytes are auth_type, fsid_type and fileid_type.
	*
	* All 4byte values are in host-byte-order.
	*
	* The auth_type field specifies how the filehandle can be authenticated
	* This might allow a file to be confirmed to be in a writable part of a
	* filetree without checking the path from it upto the root.
	* Current values:
	* 0 - No authentication. fb_auth is 0 bytes long
	* Possible future values:
	* 1 - 4 bytes taken from MD5 hash of the remainer of the file handle
	* prefixed by a secret and with the important export flags.
	*
	* The fsid_type identifies how the filesystem (or export point) is
	* encoded.
	* Current values:
	* 0 - 4 byte device id (ms-2-bytes major, ls-2-bytes minor), 4byte inode number
	* NOTE: we cannot use the kdev_t device id value, because kdev_t.h
	* says we mustn't. We must break it up and reassemble.
	* 1 - 4 byte user specified identifier
	* 2 - 4 byte major, 4 byte minor, 4 byte inode number - DEPRECATED
	* 3 - 4 byte device id, encoded for user-space, 4 byte inode number
	*
	* The fileid_type identified how the file within the filesystem is encoded.
	* This is (will be) passed to, and set by, the underlying filesystem if it supports
	* filehandle operations. The filesystem must not use the value '0' or '0xff' and may
	* only use the values 1 and 2 as defined below:
	* Current values:
	* 0 - The root, or export point, of the filesystem. fb_fileid is 0 bytes.
	* 1 - 32bit inode number, 32 bit generation number.
	* 2 - 32bit inode number, 32 bit generation number, 32 bit parent directory inode number.
	*
	*/
	struct nfs_fhbase_new {
	__u8 fb_version; /* == 1, even => nfs_fhbase_old */
	__u8 fb_auth_type;
	__u8 fb_fsid_type;
	__u8 fb_fileid_type;
	__u32 fb_auth[1];
	/* __u32 fb_fsid[0]; floating */
	/* __u32 fb_fileid[0]; floating */
	};

	struct knfsd_fh {
	unsigned int fh_size; /* significant for NFSv3.
	* Points to the current size while building
	* a new file handle
	*/
	union {
	struct nfs_fhbase_old fh_old;
	__u32 fh_pad[NFS4_FHSIZE/4];
	struct nfs_fhbase_new fh_new;
	} fh_base;
	};

	#define ofh_dcookie fh_base.fh_old.fb_dcookie
	#define ofh_ino fh_base.fh_old.fb_ino
	#define ofh_dirino fh_base.fh_old.fb_dirino
	#define ofh_dev fh_base.fh_old.fb_dev
	#define ofh_xdev fh_base.fh_old.fb_xdev
	#define ofh_xino fh_base.fh_old.fb_xino
	#define ofh_generation fh_base.fh_old.fb_generation

	#define fh_version fh_base.fh_new.fb_version
	#define fh_fsid_type fh_base.fh_new.fb_fsid_type
	#define fh_auth_type fh_base.fh_new.fb_auth_type
	#define fh_fileid_type fh_base.fh_new.fb_fileid_type
	#define fh_auth fh_base.fh_new.fb_auth
	#define fh_fsid fh_base.fh_new.fb_auth

	#ifdef __KERNEL__

	static inline __u32 ino_t_to_u32(ino_t ino)
	{
	return (__u32) ino;
	}

	static inline ino_t u32_to_ino_t(__u32 uino)
	{
	return (ino_t) uino;
	}

	/*
	* This is the internal representation of an NFS handle used in knfsd.
	* pre_mtime/post_version will be used to support wcc_attr's in NFSv3.
	*/
	typedef struct svc_fh {
	struct knfsd_fh fh_handle; /* FH data */
	struct dentry * fh_dentry; /* validated dentry */
	struct svc_export * fh_export; /* export pointer */
	int fh_maxsize; /* max size for fh_handle */

	unsigned char fh_locked; /* inode locked by us */

	#ifdef CONFIG_NFSD_V3
	unsigned char fh_post_saved; /* post-op attrs saved */
	unsigned char fh_pre_saved; /* pre-op attrs saved */

	/* Pre-op attributes saved during fh_lock */
	__u64 fh_pre_size; /* size before operation */
	struct timespec fh_pre_mtime; /* mtime before oper */
	struct timespec fh_pre_ctime; /* ctime before oper */

	/* Post-op attributes saved in fh_unlock */
	struct kstat fh_post_attr; /* full attrs after operation */
	#endif /* CONFIG_NFSD_V3 */

	} svc_fh;

	enum nfsd_fsid {
	FSID_DEV = 0,
	FSID_NUM,
	FSID_MAJOR_MINOR,
	FSID_ENCODE_DEV,
	FSID_UUID4_INUM,
	FSID_UUID8,
	FSID_UUID16,
	FSID_UUID16_INUM,
	};

	enum fsid_source {
	FSIDSOURCE_DEV,
	FSIDSOURCE_FSID,
	FSIDSOURCE_UUID,
	};
	extern enum fsid_source fsid_source(struct svc_fh *fhp);


	/* This might look a little large to "inline" but in all calls except
	* one, 'vers' is constant so moste of the function disappears.
	*/
	static inline void mk_fsid(int vers, u32 *fsidv, dev_t dev, ino_t ino,
	u32 fsid, unsigned char *uuid)
	{
	u32 *up;
	switch(vers) {
	case FSID_DEV:
	fsidv[0] = htonl((MAJOR(dev)<<16) \|
	MINOR(dev));
	fsidv[1] = ino_t_to_u32(ino);
	break;
	case FSID_NUM:
	fsidv[0] = fsid;
	break;
	case FSID_MAJOR_MINOR:
	fsidv[0] = htonl(MAJOR(dev));
	fsidv[1] = htonl(MINOR(dev));
	fsidv[2] = ino_t_to_u32(ino);
	break;

	case FSID_ENCODE_DEV:
	fsidv[0] = new_encode_dev(dev);
	fsidv[1] = ino_t_to_u32(ino);
	break;

	case FSID_UUID4_INUM:
	/* 4 byte fsid and inode number */
	up = (u32*)uuid;
	fsidv[0] = ino_t_to_u32(ino);
	fsidv[1] = up[0] ^ up[1] ^ up[2] ^ up[3];
	break;

	case FSID_UUID8:
	/* 8 byte fsid */
	up = (u32*)uuid;
	fsidv[0] = up[0] ^ up[2];
	fsidv[1] = up[1] ^ up[3];
	break;

	case FSID_UUID16:
	/* 16 byte fsid - NFSv3+ only */
	memcpy(fsidv, uuid, 16);
	break;

	case FSID_UUID16_INUM:
	/* 8 byte inode and 16 byte fsid */
	(u64)fsidv = (u64)ino;
	memcpy(fsidv+2, uuid, 16);
	break;
	default: BUG();
	}
	}

	static inline int key_len(int type)
	{
	switch(type) {
	case FSID_DEV: return 8;
	case FSID_NUM: return 4;
	case FSID_MAJOR_MINOR: return 12;
	case FSID_ENCODE_DEV: return 8;
	case FSID_UUID4_INUM: return 8;
	case FSID_UUID8: return 8;
	case FSID_UUID16: return 16;
	case FSID_UUID16_INUM: return 24;
	default: return 0;
	}
	}

	/*
	* Shorthand for dprintk()'s
	*/
	extern char * SVCFH_fmt(struct svc_fh *fhp);

	/*
	* Function prototypes
	*/
	__be32 fh_verify(struct svc_rqst , struct svc_fh , int, int);
	__be32 fh_compose(struct svc_fh , struct svc_export , struct dentry , struct svc_fh );
	__be32 fh_update(struct svc_fh *);
	void fh_put(struct svc_fh *);

	static __inline__ struct svc_fh *
	fh_copy(struct svc_fh dst, struct svc_fh src)
	{
	WARN_ON(src->fh_dentry \|\| src->fh_locked);

	dst = src;
	return dst;
	}

	static __inline__ struct svc_fh *
	fh_init(struct svc_fh *fhp, int maxsize)
	{
	memset(fhp, 0, sizeof(*fhp));
	fhp->fh_maxsize = maxsize;
	return fhp;
	}

	#ifdef CONFIG_NFSD_V3
	/*
	* Fill in the pre_op attr for the wcc data
	*/
	static inline void
	fill_pre_wcc(struct svc_fh *fhp)
	{
	struct inode *inode;

	inode = fhp->fh_dentry->d_inode;
	if (!fhp->fh_pre_saved) {
	fhp->fh_pre_mtime = inode->i_mtime;
	fhp->fh_pre_ctime = inode->i_ctime;
	fhp->fh_pre_size = inode->i_size;
	fhp->fh_pre_saved = 1;
	}
	}

	extern void fill_post_wcc(struct svc_fh *);
	#else
	#define fill_pre_wcc(ignored)
	#define fill_post_wcc(notused)
	#endif /* CONFIG_NFSD_V3 */


	/*
	* Lock a file handle/inode
	* NOTE: both fh_lock and fh_unlock are done "by hand" in
	* vfs.c:nfsd_rename as it needs to grab 2 i_mutex's at once
	* so, any changes here should be reflected there.
	*/

	static inline void
	fh_lock_nested(struct svc_fh *fhp, unsigned int subclass)
	{
	struct dentry *dentry = fhp->fh_dentry;
	struct inode *inode;

	dfprintk(FILEOP, "nfsd: fh_lock(%s) locked = %d\n",
	SVCFH_fmt(fhp), fhp->fh_locked);

	BUG_ON(!dentry);

	if (fhp->fh_locked) {
	printk(KERN_WARNING "fh_lock: %s/%s already locked!\n",
	dentry->d_parent->d_name.name, dentry->d_name.name);
	return;
	}

	inode = dentry->d_inode;
	mutex_lock_nested(&inode->i_mutex, subclass);
	fill_pre_wcc(fhp);
	fhp->fh_locked = 1;
	}

	static inline void
	fh_lock(struct svc_fh *fhp)
	{
	fh_lock_nested(fhp, I_MUTEX_NORMAL);
	}

	/*
	* Unlock a file handle/inode
	*/
	static inline void
	fh_unlock(struct svc_fh *fhp)
	{
	BUG_ON(!fhp->fh_dentry);

	if (fhp->fh_locked) {
	fill_post_wcc(fhp);
	mutex_unlock(&fhp->fh_dentry->d_inode->i_mutex);
	fhp->fh_locked = 0;
	}
	}
	#endif /* __KERNEL__ */


	#endif /* _LINUX_NFSD_FH_H */