/* * 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 <linux/types.h> #ifdef __KERNEL__ # 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 * 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 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 */