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 <okir@monad.swb.de>
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 #ifdef __KERNEL__
23 # include <linux/sunrpc/svc.h>
24 #endif
25
26 /*
27 * This is the old "dentry style" Linux NFSv2 file handle.
28 *
29 * The xino and xdev fields are currently used to transport the
30 * ino/dev of the exported inode.
31 */
32 struct nfs_fhbase_old {
33 __u32 fb_dcookie; /* dentry cookie - always 0xfeebbaca */
34 __u32 fb_ino; /* our inode number */
35 __u32 fb_dirino; /* dir inode number, 0 for directories */
36 __u32 fb_dev; /* our device */
37 __u32 fb_xdev;
38 __u32 fb_xino;
39 __u32 fb_generation;
40 };
41
42 /*
43 * This is the new flexible, extensible style NFSv2/v3 file handle.
44 * by Neil Brown <neilb@cse.unsw.edu.au> - March 2000
45 *
46 * The file handle starts with a sequence of four-byte words.
47 * The first word contains a version number (1) and three descriptor bytes
48 * that tell how the remaining 3 variable length fields should be handled.
49 * These three bytes are auth_type, fsid_type and fileid_type.
50 *
51 * All four-byte values are in host-byte-order.
52 *
53 * The auth_type field specifies how the filehandle can be authenticated
54 * This might allow a file to be confirmed to be in a writable part of a
55 * filetree without checking the path from it up to the root.
56 * Current values:
57 * 0 - No authentication. fb_auth is 0 bytes long
58 * Possible future values:
59 * 1 - 4 bytes taken from MD5 hash of the remainer of the file handle
60 * prefixed by a secret and with the important export flags.
61 *
62 * The fsid_type identifies how the filesystem (or export point) is
63 * encoded.
64 * Current values:
65 * 0 - 4 byte device id (ms-2-bytes major, ls-2-bytes minor), 4byte inode number
66 * NOTE: we cannot use the kdev_t device id value, because kdev_t.h
67 * says we mustn't. We must break it up and reassemble.
68 * 1 - 4 byte user specified identifier
69 * 2 - 4 byte major, 4 byte minor, 4 byte inode number - DEPRECATED
70 * 3 - 4 byte device id, encoded for user-space, 4 byte inode number
71 * 4 - 4 byte inode number and 4 byte uuid
72 * 5 - 8 byte uuid
73 * 6 - 16 byte uuid
74 * 7 - 8 byte inode number and 16 byte uuid
75 *
76 * The fileid_type identified how the file within the filesystem is encoded.
77 * This is (will be) passed to, and set by, the underlying filesystem if it supports
78 * filehandle operations. The filesystem must not use the value '0' or '0xff' and may
79 * only use the values 1 and 2 as defined below:
80 * Current values:
81 * 0 - The root, or export point, of the filesystem. fb_fileid is 0 bytes.
82 * 1 - 32bit inode number, 32 bit generation number.
83 * 2 - 32bit inode number, 32 bit generation number, 32 bit parent directory inode number.
84 *
85 */
86 struct nfs_fhbase_new {
87 __u8 fb_version; /* == 1, even => nfs_fhbase_old */
88 __u8 fb_auth_type;
89 __u8 fb_fsid_type;
90 __u8 fb_fileid_type;
91 __u32 fb_auth[1];
92 /* __u32 fb_fsid[0]; floating */
93 /* __u32 fb_fileid[0]; floating */
94 };
95
96 struct knfsd_fh {
97 unsigned int fh_size; /* significant for NFSv3.
98 * Points to the current size while building
99 * a new file handle
100 */
101 union {
102 struct nfs_fhbase_old fh_old;
103 __u32 fh_pad[NFS4_FHSIZE/4];
104 struct nfs_fhbase_new fh_new;
105 } fh_base;
106 };
107
108 #define ofh_dcookie fh_base.fh_old.fb_dcookie
109 #define ofh_ino fh_base.fh_old.fb_ino
110 #define ofh_dirino fh_base.fh_old.fb_dirino
111 #define ofh_dev fh_base.fh_old.fb_dev
112 #define ofh_xdev fh_base.fh_old.fb_xdev
113 #define ofh_xino fh_base.fh_old.fb_xino
114 #define ofh_generation fh_base.fh_old.fb_generation
115
116 #define fh_version fh_base.fh_new.fb_version
117 #define fh_fsid_type fh_base.fh_new.fb_fsid_type
118 #define fh_auth_type fh_base.fh_new.fb_auth_type
119 #define fh_fileid_type fh_base.fh_new.fb_fileid_type
120 #define fh_auth fh_base.fh_new.fb_auth
121 #define fh_fsid fh_base.fh_new.fb_auth
122
123 #ifdef __KERNEL__
124
ino_t_to_u32(ino_t ino)125 static inline __u32 ino_t_to_u32(ino_t ino)
126 {
127 return (__u32) ino;
128 }
129
u32_to_ino_t(__u32 uino)130 static inline ino_t u32_to_ino_t(__u32 uino)
131 {
132 return (ino_t) uino;
133 }
134
135 /*
136 * This is the internal representation of an NFS handle used in knfsd.
137 * pre_mtime/post_version will be used to support wcc_attr's in NFSv3.
138 */
139 typedef struct svc_fh {
140 struct knfsd_fh fh_handle; /* FH data */
141 struct dentry * fh_dentry; /* validated dentry */
142 struct svc_export * fh_export; /* export pointer */
143 int fh_maxsize; /* max size for fh_handle */
144
145 unsigned char fh_locked; /* inode locked by us */
146
147 #ifdef CONFIG_NFSD_V3
148 unsigned char fh_post_saved; /* post-op attrs saved */
149 unsigned char fh_pre_saved; /* pre-op attrs saved */
150
151 /* Pre-op attributes saved during fh_lock */
152 __u64 fh_pre_size; /* size before operation */
153 struct timespec fh_pre_mtime; /* mtime before oper */
154 struct timespec fh_pre_ctime; /* ctime before oper */
155 /*
156 * pre-op nfsv4 change attr: note must check IS_I_VERSION(inode)
157 * to find out if it is valid.
158 */
159 u64 fh_pre_change;
160
161 /* Post-op attributes saved in fh_unlock */
162 struct kstat fh_post_attr; /* full attrs after operation */
163 u64 fh_post_change; /* nfsv4 change; see above */
164 #endif /* CONFIG_NFSD_V3 */
165
166 } svc_fh;
167
168 #endif /* __KERNEL__ */
169
170
171 #endif /* _LINUX_NFSD_FH_H */
172