fs/nfsd/nfsfh.h - linux - Git at Google

 /* SPDX-License-Identifier: GPL-2.0 */
 /*
  * Copyright (C) 1995, 1996, 1997 Olaf Kirch <okir@monad.swb.de>
  *
  * This file describes the layout of the file handles as passed
  * over the wire.
  */
 #ifndef _LINUX_NFSD_NFSFH_H
 #define _LINUX_NFSD_NFSFH_H

 #include <linux/crc32.h>
 #include <linux/sunrpc/svc.h>
 #include <linux/iversion.h>
 #include <linux/exportfs.h>
 #include <linux/nfs4.h>

 /*
  * The file handle starts with a sequence of four-byte words.
  * The first word contains a version number (1) and three 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 four-byte values are in host-byte-order.
  *
  * The auth_type field is deprecated and must be set to 0.
  *
  * 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
  *     4  - 4 byte inode number and 4 byte uuid
  *     5  - 8 byte uuid
  *     6  - 16 byte uuid
  *     7  - 8 byte inode number and 16 byte uuid
  *
  * The fileid_type identifies how the file within the filesystem is encoded.
  *   The values for this field are filesystem specific, exccept that
  *   filesystems must not use the values '0' or '0xff'. 'See enum fid_type'
  *   in include/linux/exportfs.h for currently registered values.
  */

 struct knfsd_fh {
 	unsigned int	fh_size;	/*
 					 * Points to the current size while
 					 * building a new file handle.
 					 */
 	union {
 		char			fh_raw[NFS4_FHSIZE];
 		struct {
 			u8		fh_version;	/* == 1 */
 			u8		fh_auth_type;	/* deprecated */
 			u8		fh_fsid_type;
 			u8		fh_fileid_type;
 			u32		fh_fsid[]; /* flexible-array member */
 		};
 	};
 };

 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 */
 	int			fh_maxsize;	/* max size for fh_handle */
 	struct dentry *		fh_dentry;	/* validated dentry */
 	struct svc_export *	fh_export;	/* export pointer */

 	bool			fh_want_write;	/* remount protection taken */
 	bool			fh_no_wcc;	/* no wcc data needed */
 	bool			fh_no_atomic_attr;
 						/*
 						 * wcc data is not atomic with
 						 * operation
 						 */
 	bool			fh_use_wgather;	/* NFSv2 wgather option */
 	bool			fh_64bit_cookies;/* readdir cookie size */
 	int			fh_flags;	/* FH flags */
 	bool			fh_post_saved;	/* post-op attrs saved */
 	bool			fh_pre_saved;	/* pre-op attrs saved */

 	/* Pre-op attributes saved when inode is locked */
 	__u64			fh_pre_size;	/* size before operation */
 	struct timespec64	fh_pre_mtime;	/* mtime before oper */
 	struct timespec64	fh_pre_ctime;	/* ctime before oper */
 	/*
 	 * pre-op nfsv4 change attr: note must check IS_I_VERSION(inode)
 	 *  to find out if it is valid.
 	 */
 	u64			fh_pre_change;

 	/* Post-op attributes saved in fh_fill_post_attrs() */
 	struct kstat		fh_post_attr;	/* full attrs after operation */
 	u64			fh_post_change; /* nfsv4 change; see above */
 } svc_fh;
 #define NFSD4_FH_FOREIGN (1<<0)
 #define SET_FH_FLAG(c, f) ((c)->fh_flags |= (f))
 #define HAS_FH_FLAG(c, f) ((c)->fh_flags & (f))

 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(const 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.
  *
  * In some cases the values are considered to be host endian and in
  * others, net endian. fsidv is always considered to be u32 as the
  * callers don't know which it will be. So we must use __force to keep
  * sparse from complaining. Since these values are opaque to the
  * client, that shouldn't be a problem.
  */
 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] = (__force __u32)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] = (__force __u32)htonl(MAJOR(dev));
 		fsidv[1] = (__force __u32)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 *, umode_t, int);
 __be32	fh_verify_local(struct net *, struct svc_cred *, struct auth_domain *,
 			struct svc_fh *, umode_t, 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, const struct svc_fh *src)
 {
 	WARN_ON(src->fh_dentry);

 	*dst = *src;
 	return dst;
 }

 static inline void
 fh_copy_shallow(struct knfsd_fh *dst, const struct knfsd_fh *src)
 {
 	dst->fh_size = src->fh_size;
 	memcpy(&dst->fh_raw, &src->fh_raw, src->fh_size);
 }

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

 static inline bool fh_match(const struct knfsd_fh *fh1,
 			    const struct knfsd_fh *fh2)
 {
 	if (fh1->fh_size != fh2->fh_size)
 		return false;
 	if (memcmp(fh1->fh_raw, fh2->fh_raw, fh1->fh_size) != 0)
 		return false;
 	return true;
 }

 static inline bool fh_fsid_match(const struct knfsd_fh *fh1,
 				 const struct knfsd_fh *fh2)
 {
 	if (fh1->fh_fsid_type != fh2->fh_fsid_type)
 		return false;
 	if (memcmp(fh1->fh_fsid, fh2->fh_fsid, key_len(fh1->fh_fsid_type)) != 0)
 		return false;
 	return true;
 }

 #ifdef CONFIG_CRC32
 /**
  * knfsd_fh_hash - calculate the crc32 hash for the filehandle
  * @fh - pointer to filehandle
  *
  * returns a crc32 hash for the filehandle that is compatible with
  * the one displayed by "wireshark".
  */
 static inline u32 knfsd_fh_hash(const struct knfsd_fh *fh)
 {
 	return ~crc32_le(0xFFFFFFFF, fh->fh_raw, fh->fh_size);
 }
 #else
 static inline u32 knfsd_fh_hash(const struct knfsd_fh *fh)
 {
 	return 0;
 }
 #endif

 /**
  * fh_clear_pre_post_attrs - Reset pre/post attributes
  * @fhp: file handle to be updated
  *
  */
 static inline void fh_clear_pre_post_attrs(struct svc_fh *fhp)
 {
 	fhp->fh_post_saved = false;
 	fhp->fh_pre_saved = false;
 }

 u64 nfsd4_change_attribute(const struct kstat *stat,
 			   const struct inode *inode);
 __be32 __must_check fh_fill_pre_attrs(struct svc_fh *fhp);
 __be32 fh_fill_post_attrs(struct svc_fh *fhp);
 __be32 __must_check fh_fill_both_attrs(struct svc_fh *fhp);
 #endif /* _LINUX_NFSD_NFSFH_H */
	/* SPDX-License-Identifier: GPL-2.0 */
	/*
	* Copyright (C) 1995, 1996, 1997 Olaf Kirch <okir@monad.swb.de>
	*
	* This file describes the layout of the file handles as passed
	* over the wire.
	*/
	#ifndef _LINUX_NFSD_NFSFH_H
	#define _LINUX_NFSD_NFSFH_H

	#include <linux/crc32.h>
	#include <linux/sunrpc/svc.h>
	#include <linux/iversion.h>
	#include <linux/exportfs.h>
	#include <linux/nfs4.h>

	/*
	* The file handle starts with a sequence of four-byte words.
	* The first word contains a version number (1) and three 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 four-byte values are in host-byte-order.
	*
	* The auth_type field is deprecated and must be set to 0.
	*
	* 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
	* 4 - 4 byte inode number and 4 byte uuid
	* 5 - 8 byte uuid
	* 6 - 16 byte uuid
	* 7 - 8 byte inode number and 16 byte uuid
	*
	* The fileid_type identifies how the file within the filesystem is encoded.
	* The values for this field are filesystem specific, exccept that
	* filesystems must not use the values '0' or '0xff'. 'See enum fid_type'
	* in include/linux/exportfs.h for currently registered values.
	*/

	struct knfsd_fh {
	unsigned int fh_size; /*
	* Points to the current size while
	* building a new file handle.
	*/
	union {
	char fh_raw[NFS4_FHSIZE];
	struct {
	u8 fh_version; /* == 1 */
	u8 fh_auth_type; /* deprecated */
	u8 fh_fsid_type;
	u8 fh_fileid_type;
	u32 fh_fsid[]; /* flexible-array member */
	};
	};
	};

	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 */
	int fh_maxsize; /* max size for fh_handle */
	struct dentry * fh_dentry; /* validated dentry */
	struct svc_export * fh_export; /* export pointer */

	bool fh_want_write; /* remount protection taken */
	bool fh_no_wcc; /* no wcc data needed */
	bool fh_no_atomic_attr;
	/*
	* wcc data is not atomic with
	* operation
	*/
	bool fh_use_wgather; /* NFSv2 wgather option */
	bool fh_64bit_cookies;/* readdir cookie size */
	int fh_flags; /* FH flags */
	bool fh_post_saved; /* post-op attrs saved */
	bool fh_pre_saved; /* pre-op attrs saved */

	/* Pre-op attributes saved when inode is locked */
	__u64 fh_pre_size; /* size before operation */
	struct timespec64 fh_pre_mtime; /* mtime before oper */
	struct timespec64 fh_pre_ctime; /* ctime before oper */
	/*
	* pre-op nfsv4 change attr: note must check IS_I_VERSION(inode)
	* to find out if it is valid.
	*/
	u64 fh_pre_change;

	/* Post-op attributes saved in fh_fill_post_attrs() */
	struct kstat fh_post_attr; /* full attrs after operation */
	u64 fh_post_change; /* nfsv4 change; see above */
	} svc_fh;
	#define NFSD4_FH_FOREIGN (1<<0)
	#define SET_FH_FLAG(c, f) ((c)->fh_flags \|= (f))
	#define HAS_FH_FLAG(c, f) ((c)->fh_flags & (f))

	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(const 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.
	*
	* In some cases the values are considered to be host endian and in
	* others, net endian. fsidv is always considered to be u32 as the
	* callers don't know which it will be. So we must use __force to keep
	* sparse from complaining. Since these values are opaque to the
	* client, that shouldn't be a problem.
	*/
	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] = (__force __u32)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] = (__force __u32)htonl(MAJOR(dev));
	fsidv[1] = (__force __u32)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 , umode_t, int);
	__be32 fh_verify_local(struct net , struct svc_cred , struct auth_domain *,
	struct svc_fh *, umode_t, 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, const struct svc_fh src)
	{
	WARN_ON(src->fh_dentry);

	dst = src;
	return dst;
	}

	static inline void
	fh_copy_shallow(struct knfsd_fh dst, const struct knfsd_fh src)
	{
	dst->fh_size = src->fh_size;
	memcpy(&dst->fh_raw, &src->fh_raw, src->fh_size);
	}

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

	static inline bool fh_match(const struct knfsd_fh *fh1,
	const struct knfsd_fh *fh2)
	{
	if (fh1->fh_size != fh2->fh_size)
	return false;
	if (memcmp(fh1->fh_raw, fh2->fh_raw, fh1->fh_size) != 0)
	return false;
	return true;
	}

	static inline bool fh_fsid_match(const struct knfsd_fh *fh1,
	const struct knfsd_fh *fh2)
	{
	if (fh1->fh_fsid_type != fh2->fh_fsid_type)
	return false;
	if (memcmp(fh1->fh_fsid, fh2->fh_fsid, key_len(fh1->fh_fsid_type)) != 0)
	return false;
	return true;
	}

	#ifdef CONFIG_CRC32
	/**
	* knfsd_fh_hash - calculate the crc32 hash for the filehandle
	* @fh - pointer to filehandle
	*
	* returns a crc32 hash for the filehandle that is compatible with
	* the one displayed by "wireshark".
	*/
	static inline u32 knfsd_fh_hash(const struct knfsd_fh *fh)
	{
	return ~crc32_le(0xFFFFFFFF, fh->fh_raw, fh->fh_size);
	}
	#else
	static inline u32 knfsd_fh_hash(const struct knfsd_fh *fh)
	{
	return 0;
	}
	#endif

	/**
	* fh_clear_pre_post_attrs - Reset pre/post attributes
	* @fhp: file handle to be updated
	*
	*/
	static inline void fh_clear_pre_post_attrs(struct svc_fh *fhp)
	{
	fhp->fh_post_saved = false;
	fhp->fh_pre_saved = false;
	}

	u64 nfsd4_change_attribute(const struct kstat *stat,
	const struct inode *inode);
	__be32 __must_check fh_fill_pre_attrs(struct svc_fh *fhp);
	__be32 fh_fill_post_attrs(struct svc_fh *fhp);
	__be32 __must_check fh_fill_both_attrs(struct svc_fh *fhp);
	#endif /* _LINUX_NFSD_NFSFH_H */