1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * linux/net/sunrpc/auth_null.c
4 *
5 * AUTH_NULL authentication. Really :-)
6 *
7 * Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de>
8 */
9
10 #include <linux/types.h>
11 #include <linux/module.h>
12 #include <linux/sunrpc/clnt.h>
13
14 #if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
15 # define RPCDBG_FACILITY RPCDBG_AUTH
16 #endif
17
18 static struct rpc_auth null_auth;
19 static struct rpc_cred null_cred;
20
21 static struct rpc_auth *
nul_create(const struct rpc_auth_create_args * args,struct rpc_clnt * clnt)22 nul_create(const struct rpc_auth_create_args *args, struct rpc_clnt *clnt)
23 {
24 refcount_inc(&null_auth.au_count);
25 return &null_auth;
26 }
27
28 static void
nul_destroy(struct rpc_auth * auth)29 nul_destroy(struct rpc_auth *auth)
30 {
31 }
32
33 /*
34 * Lookup NULL creds for current process
35 */
36 static struct rpc_cred *
nul_lookup_cred(struct rpc_auth * auth,struct auth_cred * acred,int flags)37 nul_lookup_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags)
38 {
39 return get_rpccred(&null_cred);
40 }
41
42 /*
43 * Destroy cred handle.
44 */
45 static void
nul_destroy_cred(struct rpc_cred * cred)46 nul_destroy_cred(struct rpc_cred *cred)
47 {
48 }
49
50 /*
51 * Match cred handle against current process
52 */
53 static int
nul_match(struct auth_cred * acred,struct rpc_cred * cred,int taskflags)54 nul_match(struct auth_cred *acred, struct rpc_cred *cred, int taskflags)
55 {
56 return 1;
57 }
58
59 /*
60 * Marshal credential.
61 */
62 static int
nul_marshal(struct rpc_task * task,struct xdr_stream * xdr)63 nul_marshal(struct rpc_task *task, struct xdr_stream *xdr)
64 {
65 __be32 *p;
66
67 p = xdr_reserve_space(xdr, 4 * sizeof(*p));
68 if (!p)
69 return -EMSGSIZE;
70 /* Credential */
71 *p++ = rpc_auth_null;
72 *p++ = xdr_zero;
73 /* Verifier */
74 *p++ = rpc_auth_null;
75 *p = xdr_zero;
76 return 0;
77 }
78
79 /*
80 * Refresh credential. This is a no-op for AUTH_NULL
81 */
82 static int
nul_refresh(struct rpc_task * task)83 nul_refresh(struct rpc_task *task)
84 {
85 set_bit(RPCAUTH_CRED_UPTODATE, &task->tk_rqstp->rq_cred->cr_flags);
86 return 0;
87 }
88
89 static int
nul_validate(struct rpc_task * task,struct xdr_stream * xdr)90 nul_validate(struct rpc_task *task, struct xdr_stream *xdr)
91 {
92 __be32 *p;
93
94 p = xdr_inline_decode(xdr, 2 * sizeof(*p));
95 if (!p)
96 return -EIO;
97 if (*p++ != rpc_auth_null)
98 return -EIO;
99 if (*p != xdr_zero)
100 return -EIO;
101 return 0;
102 }
103
104 const struct rpc_authops authnull_ops = {
105 .owner = THIS_MODULE,
106 .au_flavor = RPC_AUTH_NULL,
107 .au_name = "NULL",
108 .create = nul_create,
109 .destroy = nul_destroy,
110 .lookup_cred = nul_lookup_cred,
111 };
112
113 static
114 struct rpc_auth null_auth = {
115 .au_cslack = NUL_CALLSLACK,
116 .au_rslack = NUL_REPLYSLACK,
117 .au_verfsize = NUL_REPLYSLACK,
118 .au_ralign = NUL_REPLYSLACK,
119 .au_ops = &authnull_ops,
120 .au_flavor = RPC_AUTH_NULL,
121 .au_count = REFCOUNT_INIT(1),
122 };
123
124 static
125 const struct rpc_credops null_credops = {
126 .cr_name = "AUTH_NULL",
127 .crdestroy = nul_destroy_cred,
128 .crmatch = nul_match,
129 .crmarshal = nul_marshal,
130 .crwrap_req = rpcauth_wrap_req_encode,
131 .crrefresh = nul_refresh,
132 .crvalidate = nul_validate,
133 .crunwrap_resp = rpcauth_unwrap_resp_decode,
134 };
135
136 static
137 struct rpc_cred null_cred = {
138 .cr_lru = LIST_HEAD_INIT(null_cred.cr_lru),
139 .cr_auth = &null_auth,
140 .cr_ops = &null_credops,
141 .cr_count = REFCOUNT_INIT(2),
142 .cr_flags = 1UL << RPCAUTH_CRED_UPTODATE,
143 };
144