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Diffstat (limited to 'include/linux/nfsd/nfsfh.h')
| -rw-r--r-- | include/linux/nfsd/nfsfh.h | 343 |
1 files changed, 343 insertions, 0 deletions
diff --git a/include/linux/nfsd/nfsfh.h b/include/linux/nfsd/nfsfh.h new file mode 100644 index 000000000000..bb842ea41033 --- /dev/null +++ b/include/linux/nfsd/nfsfh.h @@ -0,0 +1,343 @@ +/* + * 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/config.h> +# 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 */ + umode_t fh_post_mode; /* i_mode */ + nlink_t fh_post_nlink; /* i_nlink */ + uid_t fh_post_uid; /* i_uid */ + gid_t fh_post_gid; /* i_gid */ + __u64 fh_post_size; /* i_size */ + unsigned long fh_post_blocks; /* i_blocks */ + unsigned long fh_post_blksize;/* i_blksize */ + __u32 fh_post_rdev[2];/* i_rdev */ + struct timespec fh_post_atime; /* i_atime */ + struct timespec fh_post_mtime; /* i_mtime */ + struct timespec fh_post_ctime; /* i_ctime */ +#endif /* CONFIG_NFSD_V3 */ + +} svc_fh; + +static inline void mk_fsid_v0(u32 *fsidv, dev_t dev, ino_t ino) +{ + fsidv[0] = htonl((MAJOR(dev)<<16) | + MINOR(dev)); + fsidv[1] = ino_t_to_u32(ino); +} + +static inline void mk_fsid_v1(u32 *fsidv, u32 fsid) +{ + fsidv[0] = fsid; +} + +static inline void mk_fsid_v2(u32 *fsidv, dev_t dev, ino_t ino) +{ + fsidv[0] = htonl(MAJOR(dev)); + fsidv[1] = htonl(MINOR(dev)); + fsidv[2] = ino_t_to_u32(ino); +} + +static inline void mk_fsid_v3(u32 *fsidv, dev_t dev, ino_t ino) +{ + fsidv[0] = new_encode_dev(dev); + fsidv[1] = ino_t_to_u32(ino); +} + +static inline int key_len(int type) +{ + switch(type) { + case 0: return 8; + case 1: return 4; + case 2: return 12; + case 3: return 8; + default: return 0; + } +} + +/* + * Shorthand for dprintk()'s + */ +extern char * SVCFH_fmt(struct svc_fh *fhp); + +/* + * Function prototypes + */ +u32 fh_verify(struct svc_rqst *, struct svc_fh *, int, int); +int fh_compose(struct svc_fh *, struct svc_export *, struct dentry *, struct svc_fh *); +int 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) +{ + if (src->fh_dentry || src->fh_locked) { + struct dentry *dentry = src->fh_dentry; + printk(KERN_ERR "fh_copy: copying %s/%s, already verified!\n", + dentry->d_parent->d_name.name, dentry->d_name.name); + } + + *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; + } +} + +/* + * Fill in the post_op attr for the wcc data + */ +static inline void +fill_post_wcc(struct svc_fh *fhp) +{ + struct inode *inode = fhp->fh_dentry->d_inode; + + if (fhp->fh_post_saved) + printk("nfsd: inode locked twice during operation.\n"); + + fhp->fh_post_mode = inode->i_mode; + fhp->fh_post_nlink = inode->i_nlink; + fhp->fh_post_uid = inode->i_uid; + fhp->fh_post_gid = inode->i_gid; + fhp->fh_post_size = inode->i_size; + if (inode->i_blksize) { + fhp->fh_post_blksize = inode->i_blksize; + fhp->fh_post_blocks = inode->i_blocks; + } else { + fhp->fh_post_blksize = BLOCK_SIZE; + /* how much do we care for accuracy with MinixFS? */ + fhp->fh_post_blocks = (inode->i_size+511) >> 9; + } + fhp->fh_post_rdev[0] = htonl((u32)imajor(inode)); + fhp->fh_post_rdev[1] = htonl((u32)iminor(inode)); + fhp->fh_post_atime = inode->i_atime; + fhp->fh_post_mtime = inode->i_mtime; + fhp->fh_post_ctime = inode->i_ctime; + fhp->fh_post_saved = 1; +} +#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_sem's at once + * so, any changes here should be reflected there. + */ +static inline void +fh_lock(struct svc_fh *fhp) +{ + struct dentry *dentry = fhp->fh_dentry; + struct inode *inode; + + dfprintk(FILEOP, "nfsd: fh_lock(%s) locked = %d\n", + SVCFH_fmt(fhp), fhp->fh_locked); + + if (!fhp->fh_dentry) { + printk(KERN_ERR "fh_lock: fh not verified!\n"); + return; + } + 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; + down(&inode->i_sem); + fill_pre_wcc(fhp); + fhp->fh_locked = 1; +} + +/* + * Unlock a file handle/inode + */ +static inline void +fh_unlock(struct svc_fh *fhp) +{ + if (!fhp->fh_dentry) + printk(KERN_ERR "fh_unlock: fh not verified!\n"); + + if (fhp->fh_locked) { + fill_post_wcc(fhp); + up(&fhp->fh_dentry->d_inode->i_sem); + fhp->fh_locked = 0; + } +} +#endif /* __KERNEL__ */ + + +#endif /* _LINUX_NFSD_FH_H */ |