xref: /openbmc/linux/net/sunrpc/auth_null.c (revision 35e77d21)
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