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 #include <linux/sunrpc/sched.h>
14 #include <linux/sunrpc/msg_prot.h>
15 #include <linux/sunrpc/xdr.h>
16
17 #include <linux/atomic.h>
18 #include <linux/rcupdate.h>
19 #include <linux/uidgid.h>
20 #include <linux/utsname.h>
21
22 /*
23 * Maximum size of AUTH_NONE authentication information, in XDR words.
24 */
25 #define NUL_CALLSLACK (4)
26 #define NUL_REPLYSLACK (2)
27
28 /*
29 * Size of the nodename buffer. RFC1831 specifies a hard limit of 255 bytes,
30 * but Linux hostnames are actually limited to __NEW_UTS_LEN bytes.
31 */
32 #define UNX_MAXNODENAME __NEW_UTS_LEN
33 #define UNX_CALLSLACK (21 + XDR_QUADLEN(UNX_MAXNODENAME))
34 #define UNX_NGROUPS 16
35
36 struct rpcsec_gss_info;
37
38 struct auth_cred {
39 const struct cred *cred;
40 const char *principal; /* If present, this is a machine credential */
41 };
42
43 /*
44 * Client user credentials
45 */
46 struct rpc_auth;
47 struct rpc_credops;
48 struct rpc_cred {
49 struct hlist_node cr_hash; /* hash chain */
50 struct list_head cr_lru; /* lru garbage collection */
51 struct rcu_head cr_rcu;
52 struct rpc_auth * cr_auth;
53 const struct rpc_credops *cr_ops;
54 unsigned long cr_expire; /* when to gc */
55 unsigned long cr_flags; /* various flags */
56 refcount_t cr_count; /* ref count */
57 const struct cred *cr_cred;
58
59 /* per-flavor data */
60 };
61 #define RPCAUTH_CRED_NEW 0
62 #define RPCAUTH_CRED_UPTODATE 1
63 #define RPCAUTH_CRED_HASHED 2
64 #define RPCAUTH_CRED_NEGATIVE 3
65
66 const struct cred *rpc_machine_cred(void);
67
68 /*
69 * Client authentication handle
70 */
71 struct rpc_cred_cache;
72 struct rpc_authops;
73 struct rpc_auth {
74 unsigned int au_cslack; /* call cred size estimate */
75 unsigned int au_rslack; /* reply cred size estimate */
76 unsigned int au_verfsize; /* size of reply verifier */
77 unsigned int au_ralign; /* words before UL header */
78
79 unsigned long au_flags;
80 const struct rpc_authops *au_ops;
81 rpc_authflavor_t au_flavor; /* pseudoflavor (note may
82 * differ from the flavor in
83 * au_ops->au_flavor in gss
84 * case) */
85 refcount_t au_count; /* Reference counter */
86
87 struct rpc_cred_cache * au_credcache;
88 /* per-flavor data */
89 };
90
91 /* rpc_auth au_flags */
92 #define RPCAUTH_AUTH_DATATOUCH (1)
93 #define RPCAUTH_AUTH_UPDATE_SLACK (2)
94
95 struct rpc_auth_create_args {
96 rpc_authflavor_t pseudoflavor;
97 const char *target_name;
98 };
99
100 /* Flags for rpcauth_lookupcred() */
101 #define RPCAUTH_LOOKUP_NEW 0x01 /* Accept an uninitialised cred */
102 #define RPCAUTH_LOOKUP_ASYNC 0x02 /* Don't block waiting for memory */
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 rpc_authflavor_t (*info2flavor)(struct rpcsec_gss_info *);
119 int (*flavor2info)(rpc_authflavor_t,
120 struct rpcsec_gss_info *);
121 int (*key_timeout)(struct rpc_auth *,
122 struct rpc_cred *);
123 int (*ping)(struct rpc_clnt *clnt);
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 extern const struct rpc_authops authtls_ops;
149
150 int __init rpc_init_authunix(void);
151 int __init rpcauth_init_module(void);
152 void rpcauth_remove_module(void);
153 void rpc_destroy_authunix(void);
154
155 int rpcauth_register(const struct rpc_authops *);
156 int rpcauth_unregister(const struct rpc_authops *);
157 struct rpc_auth * rpcauth_create(const struct rpc_auth_create_args *,
158 struct rpc_clnt *);
159 void rpcauth_release(struct rpc_auth *);
160 rpc_authflavor_t rpcauth_get_pseudoflavor(rpc_authflavor_t,
161 struct rpcsec_gss_info *);
162 int rpcauth_get_gssinfo(rpc_authflavor_t,
163 struct rpcsec_gss_info *);
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 /* _LINUX_SUNRPC_AUTH_H */
198