1 /* 2 * include/linux/nfsd/nfsfh.h 3 * 4 * This file describes the layout of the file handles as passed 5 * over the wire. 6 * 7 * Earlier versions of knfsd used to sign file handles using keyed MD5 8 * or SHA. I've removed this code, because it doesn't give you more 9 * security than blocking external access to port 2049 on your firewall. 10 * 11 * Copyright (C) 1995, 1996, 1997 Olaf Kirch <[email protected]> 12 */ 13 14 #ifndef _LINUX_NFSD_FH_H 15 #define _LINUX_NFSD_FH_H 16 17 #include <linux/types.h> 18 #include <linux/nfs.h> 19 #include <linux/nfs2.h> 20 #include <linux/nfs3.h> 21 #include <linux/nfs4.h> 22 23 /* 24 * This is the old "dentry style" Linux NFSv2 file handle. 25 * 26 * The xino and xdev fields are currently used to transport the 27 * ino/dev of the exported inode. 28 */ 29 struct nfs_fhbase_old { 30 __u32 fb_dcookie; /* dentry cookie - always 0xfeebbaca */ 31 __u32 fb_ino; /* our inode number */ 32 __u32 fb_dirino; /* dir inode number, 0 for directories */ 33 __u32 fb_dev; /* our device */ 34 __u32 fb_xdev; 35 __u32 fb_xino; 36 __u32 fb_generation; 37 }; 38 39 /* 40 * This is the new flexible, extensible style NFSv2/v3 file handle. 41 * by Neil Brown <[email protected]> - March 2000 42 * 43 * The file handle starts with a sequence of four-byte words. 44 * The first word contains a version number (1) and three descriptor bytes 45 * that tell how the remaining 3 variable length fields should be handled. 46 * These three bytes are auth_type, fsid_type and fileid_type. 47 * 48 * All four-byte values are in host-byte-order. 49 * 50 * The auth_type field specifies how the filehandle can be authenticated 51 * This might allow a file to be confirmed to be in a writable part of a 52 * filetree without checking the path from it up to the root. 53 * Current values: 54 * 0 - No authentication. fb_auth is 0 bytes long 55 * Possible future values: 56 * 1 - 4 bytes taken from MD5 hash of the remainer of the file handle 57 * prefixed by a secret and with the important export flags. 58 * 59 * The fsid_type identifies how the filesystem (or export point) is 60 * encoded. 61 * Current values: 62 * 0 - 4 byte device id (ms-2-bytes major, ls-2-bytes minor), 4byte inode number 63 * NOTE: we cannot use the kdev_t device id value, because kdev_t.h 64 * says we mustn't. We must break it up and reassemble. 65 * 1 - 4 byte user specified identifier 66 * 2 - 4 byte major, 4 byte minor, 4 byte inode number - DEPRECATED 67 * 3 - 4 byte device id, encoded for user-space, 4 byte inode number 68 * 4 - 4 byte inode number and 4 byte uuid 69 * 5 - 8 byte uuid 70 * 6 - 16 byte uuid 71 * 7 - 8 byte inode number and 16 byte uuid 72 * 73 * The fileid_type identified how the file within the filesystem is encoded. 74 * This is (will be) passed to, and set by, the underlying filesystem if it supports 75 * filehandle operations. The filesystem must not use the value '0' or '0xff' and may 76 * only use the values 1 and 2 as defined below: 77 * Current values: 78 * 0 - The root, or export point, of the filesystem. fb_fileid is 0 bytes. 79 * 1 - 32bit inode number, 32 bit generation number. 80 * 2 - 32bit inode number, 32 bit generation number, 32 bit parent directory inode number. 81 * 82 */ 83 struct nfs_fhbase_new { 84 __u8 fb_version; /* == 1, even => nfs_fhbase_old */ 85 __u8 fb_auth_type; 86 __u8 fb_fsid_type; 87 __u8 fb_fileid_type; 88 __u32 fb_auth[1]; 89 /* __u32 fb_fsid[0]; floating */ 90 /* __u32 fb_fileid[0]; floating */ 91 }; 92 93 struct knfsd_fh { 94 unsigned int fh_size; /* significant for NFSv3. 95 * Points to the current size while building 96 * a new file handle 97 */ 98 union { 99 struct nfs_fhbase_old fh_old; 100 __u32 fh_pad[NFS4_FHSIZE/4]; 101 struct nfs_fhbase_new fh_new; 102 } fh_base; 103 }; 104 105 #define ofh_dcookie fh_base.fh_old.fb_dcookie 106 #define ofh_ino fh_base.fh_old.fb_ino 107 #define ofh_dirino fh_base.fh_old.fb_dirino 108 #define ofh_dev fh_base.fh_old.fb_dev 109 #define ofh_xdev fh_base.fh_old.fb_xdev 110 #define ofh_xino fh_base.fh_old.fb_xino 111 #define ofh_generation fh_base.fh_old.fb_generation 112 113 #define fh_version fh_base.fh_new.fb_version 114 #define fh_fsid_type fh_base.fh_new.fb_fsid_type 115 #define fh_auth_type fh_base.fh_new.fb_auth_type 116 #define fh_fileid_type fh_base.fh_new.fb_fileid_type 117 #define fh_auth fh_base.fh_new.fb_auth 118 #define fh_fsid fh_base.fh_new.fb_auth 119 120 121 122 #endif /* _LINUX_NFSD_FH_H */ 123