1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3 * linux/include/linux/sunrpc/auth.h
4 *
5 * Declarations for the RPC client authentication machinery.
6 *
7 * Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de>
8 */
9
10 #ifndef _LINUX_SUNRPC_AUTH_H
11 #define _LINUX_SUNRPC_AUTH_H
12
13 #ifdef __KERNEL__
14
15 #include <linux/sunrpc/sched.h>
16 #include <linux/sunrpc/msg_prot.h>
17 #include <linux/sunrpc/xdr.h>
18
19 #include <linux/atomic.h>
20 #include <linux/rcupdate.h>
21 #include <linux/uidgid.h>
22 #include <linux/utsname.h>
23
24 /*
25 * Maximum size of AUTH_NONE authentication information, in XDR words.
26 */
27 #define NUL_CALLSLACK (4)
28 #define NUL_REPLYSLACK (2)
29
30 /*
31 * Size of the nodename buffer. RFC1831 specifies a hard limit of 255 bytes,
32 * but Linux hostnames are actually limited to __NEW_UTS_LEN bytes.
33 */
34 #define UNX_MAXNODENAME __NEW_UTS_LEN
35 #define UNX_CALLSLACK (21 + XDR_QUADLEN(UNX_MAXNODENAME))
36 #define UNX_NGROUPS 16
37
38 struct rpcsec_gss_info;
39
40 struct auth_cred {
41 const struct cred *cred;
42 const char *principal; /* If present, this is a machine credential */
43 };
44
45 /*
46 * Client user credentials
47 */
48 struct rpc_auth;
49 struct rpc_credops;
50 struct rpc_cred {
51 struct hlist_node cr_hash; /* hash chain */
52 struct list_head cr_lru; /* lru garbage collection */
53 struct rcu_head cr_rcu;
54 struct rpc_auth * cr_auth;
55 const struct rpc_credops *cr_ops;
56 unsigned long cr_expire; /* when to gc */
57 unsigned long cr_flags; /* various flags */
58 refcount_t cr_count; /* ref count */
59 const struct cred *cr_cred;
60
61 /* per-flavor data */
62 };
63 #define RPCAUTH_CRED_NEW 0
64 #define RPCAUTH_CRED_UPTODATE 1
65 #define RPCAUTH_CRED_HASHED 2
66 #define RPCAUTH_CRED_NEGATIVE 3
67
68 const struct cred *rpc_machine_cred(void);
69
70 /*
71 * Client authentication handle
72 */
73 struct rpc_cred_cache;
74 struct rpc_authops;
75 struct rpc_auth {
76 unsigned int au_cslack; /* call cred size estimate */
77 unsigned int au_rslack; /* reply cred size estimate */
78 unsigned int au_verfsize; /* size of reply verifier */
79 unsigned int au_ralign; /* words before UL header */
80
81 unsigned int au_flags;
82 const struct rpc_authops *au_ops;
83 rpc_authflavor_t au_flavor; /* pseudoflavor (note may
84 * differ from the flavor in
85 * au_ops->au_flavor in gss
86 * case) */
87 refcount_t au_count; /* Reference counter */
88
89 struct rpc_cred_cache * au_credcache;
90 /* per-flavor data */
91 };
92
93 /* rpc_auth au_flags */
94 #define RPCAUTH_AUTH_DATATOUCH 0x00000002
95
96 struct rpc_auth_create_args {
97 rpc_authflavor_t pseudoflavor;
98 const char *target_name;
99 };
100
101 /* Flags for rpcauth_lookupcred() */
102 #define RPCAUTH_LOOKUP_NEW 0x01 /* Accept an uninitialised cred */
103
104 /*
105 * Client authentication ops
106 */
107 struct rpc_authops {
108 struct module *owner;
109 rpc_authflavor_t au_flavor; /* flavor (RPC_AUTH_*) */
110 char * au_name;
111 struct rpc_auth * (*create)(const struct rpc_auth_create_args *,
112 struct rpc_clnt *);
113 void (*destroy)(struct rpc_auth *);
114
115 int (*hash_cred)(struct auth_cred *, unsigned int);
116 struct rpc_cred * (*lookup_cred)(struct rpc_auth *, struct auth_cred *, int);
117 struct rpc_cred * (*crcreate)(struct rpc_auth*, struct auth_cred *, int, gfp_t);
118 int (*list_pseudoflavors)(rpc_authflavor_t *, int);
119 rpc_authflavor_t (*info2flavor)(struct rpcsec_gss_info *);
120 int (*flavor2info)(rpc_authflavor_t,
121 struct rpcsec_gss_info *);
122 int (*key_timeout)(struct rpc_auth *,
123 struct rpc_cred *);
124 };
125
126 struct rpc_credops {
127 const char * cr_name; /* Name of the auth flavour */
128 int (*cr_init)(struct rpc_auth *, struct rpc_cred *);
129 void (*crdestroy)(struct rpc_cred *);
130
131 int (*crmatch)(struct auth_cred *, struct rpc_cred *, int);
132 int (*crmarshal)(struct rpc_task *task,
133 struct xdr_stream *xdr);
134 int (*crrefresh)(struct rpc_task *);
135 int (*crvalidate)(struct rpc_task *task,
136 struct xdr_stream *xdr);
137 int (*crwrap_req)(struct rpc_task *task,
138 struct xdr_stream *xdr);
139 int (*crunwrap_resp)(struct rpc_task *task,
140 struct xdr_stream *xdr);
141 int (*crkey_timeout)(struct rpc_cred *);
142 char * (*crstringify_acceptor)(struct rpc_cred *);
143 bool (*crneed_reencode)(struct rpc_task *);
144 };
145
146 extern const struct rpc_authops authunix_ops;
147 extern const struct rpc_authops authnull_ops;
148
149 int __init rpc_init_authunix(void);
150 int __init rpcauth_init_module(void);
151 void rpcauth_remove_module(void);
152 void rpc_destroy_authunix(void);
153
154 int rpcauth_register(const struct rpc_authops *);
155 int rpcauth_unregister(const struct rpc_authops *);
156 struct rpc_auth * rpcauth_create(const struct rpc_auth_create_args *,
157 struct rpc_clnt *);
158 void rpcauth_release(struct rpc_auth *);
159 rpc_authflavor_t rpcauth_get_pseudoflavor(rpc_authflavor_t,
160 struct rpcsec_gss_info *);
161 int rpcauth_get_gssinfo(rpc_authflavor_t,
162 struct rpcsec_gss_info *);
163 int rpcauth_list_flavors(rpc_authflavor_t *, int);
164 struct rpc_cred * rpcauth_lookup_credcache(struct rpc_auth *, struct auth_cred *, int, gfp_t);
165 void rpcauth_init_cred(struct rpc_cred *, const struct auth_cred *, struct rpc_auth *, const struct rpc_credops *);
166 struct rpc_cred * rpcauth_lookupcred(struct rpc_auth *, int);
167 void put_rpccred(struct rpc_cred *);
168 int rpcauth_marshcred(struct rpc_task *task,
169 struct xdr_stream *xdr);
170 int rpcauth_checkverf(struct rpc_task *task,
171 struct xdr_stream *xdr);
172 int rpcauth_wrap_req_encode(struct rpc_task *task,
173 struct xdr_stream *xdr);
174 int rpcauth_wrap_req(struct rpc_task *task,
175 struct xdr_stream *xdr);
176 int rpcauth_unwrap_resp_decode(struct rpc_task *task,
177 struct xdr_stream *xdr);
178 int rpcauth_unwrap_resp(struct rpc_task *task,
179 struct xdr_stream *xdr);
180 bool rpcauth_xmit_need_reencode(struct rpc_task *task);
181 int rpcauth_refreshcred(struct rpc_task *);
182 void rpcauth_invalcred(struct rpc_task *);
183 int rpcauth_uptodatecred(struct rpc_task *);
184 int rpcauth_init_credcache(struct rpc_auth *);
185 void rpcauth_destroy_credcache(struct rpc_auth *);
186 void rpcauth_clear_credcache(struct rpc_cred_cache *);
187 char * rpcauth_stringify_acceptor(struct rpc_cred *);
188
189 static inline
get_rpccred(struct rpc_cred * cred)190 struct rpc_cred *get_rpccred(struct rpc_cred *cred)
191 {
192 if (cred != NULL && refcount_inc_not_zero(&cred->cr_count))
193 return cred;
194 return NULL;
195 }
196
197 #endif /* __KERNEL__ */
198 #endif /* _LINUX_SUNRPC_AUTH_H */
199
