1 /*
2  * include/linux/nfsd/export.h
3  *
4  * Public declarations for NFS exports. The definitions for the
5  * syscall interface are in nfsctl.h
6  *
7  * Copyright (C) 1995-1997 Olaf Kirch <okir@monad.swb.de>
8  */
9 
10 #ifndef NFSD_EXPORT_H
11 #define NFSD_EXPORT_H
12 
13 # include <linux/types.h>
14 #ifdef __KERNEL__
15 # include <linux/nfsd/nfsfh.h>
16 #endif
17 
18 /*
19  * Important limits for the exports stuff.
20  */
21 #define NFSCLNT_IDMAX		1024
22 #define NFSCLNT_ADDRMAX		16
23 #define NFSCLNT_KEYMAX		32
24 
25 /*
26  * Export flags.
27  */
28 #define NFSEXP_READONLY		0x0001
29 #define NFSEXP_INSECURE_PORT	0x0002
30 #define NFSEXP_ROOTSQUASH	0x0004
31 #define NFSEXP_ALLSQUASH	0x0008
32 #define NFSEXP_ASYNC		0x0010
33 #define NFSEXP_GATHERED_WRITES	0x0020
34 /* 40 80 100 currently unused */
35 #define NFSEXP_NOHIDE		0x0200
36 #define NFSEXP_NOSUBTREECHECK	0x0400
37 #define	NFSEXP_NOAUTHNLM	0x0800		/* Don't authenticate NLM requests - just trust */
38 #define NFSEXP_MSNFS		0x1000	/* do silly things that MS clients expect; no longer supported */
39 #define NFSEXP_FSID		0x2000
40 #define	NFSEXP_CROSSMOUNT	0x4000
41 #define	NFSEXP_NOACL		0x8000	/* reserved for possible ACL related use */
42 /*
43  * The NFSEXP_V4ROOT flag causes the kernel to give access only to NFSv4
44  * clients, and only to the single directory that is the root of the
45  * export; further lookup and readdir operations are treated as if every
46  * subdirectory was a mountpoint, and ignored if they are not themselves
47  * exported.  This is used by nfsd and mountd to construct the NFSv4
48  * pseudofilesystem, which provides access only to paths leading to each
49  * exported filesystem.
50  */
51 #define	NFSEXP_V4ROOT		0x10000
52 /* All flags that we claim to support.  (Note we don't support NOACL.) */
53 #define NFSEXP_ALLFLAGS		0x17E3F
54 
55 /* The flags that may vary depending on security flavor: */
56 #define NFSEXP_SECINFO_FLAGS	(NFSEXP_READONLY | NFSEXP_ROOTSQUASH \
57 					| NFSEXP_ALLSQUASH \
58 					| NFSEXP_INSECURE_PORT)
59 
60 #ifdef __KERNEL__
61 
62 /*
63  * FS Locations
64  */
65 
66 #define MAX_FS_LOCATIONS	128
67 
68 struct nfsd4_fs_location {
69 	char *hosts; /* colon separated list of hosts */
70 	char *path;  /* slash separated list of path components */
71 };
72 
73 struct nfsd4_fs_locations {
74 	uint32_t locations_count;
75 	struct nfsd4_fs_location *locations;
76 /* If we're not actually serving this data ourselves (only providing a
77  * list of replicas that do serve it) then we set "migrated": */
78 	int migrated;
79 };
80 
81 /*
82  * We keep an array of pseudoflavors with the export, in order from most
83  * to least preferred.  For the foreseeable future, we don't expect more
84  * than the eight pseudoflavors null, unix, krb5, krb5i, krb5p, skpm3,
85  * spkm3i, and spkm3p (and using all 8 at once should be rare).
86  */
87 #define MAX_SECINFO_LIST	8
88 
89 struct exp_flavor_info {
90 	u32	pseudoflavor;
91 	u32	flags;
92 };
93 
94 struct svc_export {
95 	struct cache_head	h;
96 	struct auth_domain *	ex_client;
97 	int			ex_flags;
98 	struct path		ex_path;
99 	char			*ex_pathname;
100 	uid_t			ex_anon_uid;
101 	gid_t			ex_anon_gid;
102 	int			ex_fsid;
103 	unsigned char *		ex_uuid; /* 16 byte fsid */
104 	struct nfsd4_fs_locations ex_fslocs;
105 	int			ex_nflavors;
106 	struct exp_flavor_info	ex_flavors[MAX_SECINFO_LIST];
107 };
108 
109 /* an "export key" (expkey) maps a filehandlefragement to an
110  * svc_export for a given client.  There can be several per export,
111  * for the different fsid types.
112  */
113 struct svc_expkey {
114 	struct cache_head	h;
115 
116 	struct auth_domain *	ek_client;
117 	int			ek_fsidtype;
118 	u32			ek_fsid[6];
119 
120 	struct path		ek_path;
121 };
122 
123 #define EX_ISSYNC(exp)		(!((exp)->ex_flags & NFSEXP_ASYNC))
124 #define EX_NOHIDE(exp)		((exp)->ex_flags & NFSEXP_NOHIDE)
125 #define EX_WGATHER(exp)		((exp)->ex_flags & NFSEXP_GATHERED_WRITES)
126 
127 int nfsexp_flags(struct svc_rqst *rqstp, struct svc_export *exp);
128 __be32 check_nfsd_access(struct svc_export *exp, struct svc_rqst *rqstp);
129 
130 /*
131  * Function declarations
132  */
133 int			nfsd_export_init(void);
134 void			nfsd_export_shutdown(void);
135 void			nfsd_export_flush(void);
136 void			exp_readlock(void);
137 void			exp_readunlock(void);
138 struct svc_export *	rqst_exp_get_by_name(struct svc_rqst *,
139 					     struct path *);
140 struct svc_export *	rqst_exp_parent(struct svc_rqst *,
141 					struct path *);
142 int			exp_rootfh(struct auth_domain *,
143 					char *path, struct knfsd_fh *, int maxsize);
144 __be32			exp_pseudoroot(struct svc_rqst *, struct svc_fh *);
145 __be32			nfserrno(int errno);
146 
147 extern struct cache_detail svc_export_cache;
148 
exp_put(struct svc_export * exp)149 static inline void exp_put(struct svc_export *exp)
150 {
151 	cache_put(&exp->h, &svc_export_cache);
152 }
153 
exp_get(struct svc_export * exp)154 static inline void exp_get(struct svc_export *exp)
155 {
156 	cache_get(&exp->h);
157 }
158 struct svc_export * rqst_exp_find(struct svc_rqst *, int, u32 *);
159 
160 #endif /* __KERNEL__ */
161 
162 #endif /* NFSD_EXPORT_H */
163 
164