xref: /linux/net/sunrpc/auth_null.c (revision 9f7d35d9f7a184ffb591b090b2cbf63d2d599c02)
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 *
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
29 nul_destroy(struct rpc_auth *auth)
30 {
31 }
32 
33 /*
34  * Lookup NULL creds for current process
35  */
36 static struct rpc_cred *
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
46 nul_destroy_cred(struct rpc_cred *cred)
47 {
48 }
49 
50 /*
51  * Match cred handle against current process
52  */
53 static int
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 __be32 *
63 nul_marshal(struct rpc_task *task, __be32 *p)
64 {
65 	*p++ = htonl(RPC_AUTH_NULL);
66 	*p++ = 0;
67 	*p++ = htonl(RPC_AUTH_NULL);
68 	*p++ = 0;
69 
70 	return p;
71 }
72 
73 /*
74  * Refresh credential. This is a no-op for AUTH_NULL
75  */
76 static int
77 nul_refresh(struct rpc_task *task)
78 {
79 	set_bit(RPCAUTH_CRED_UPTODATE, &task->tk_rqstp->rq_cred->cr_flags);
80 	return 0;
81 }
82 
83 static __be32 *
84 nul_validate(struct rpc_task *task, __be32 *p)
85 {
86 	rpc_authflavor_t	flavor;
87 	u32			size;
88 
89 	flavor = ntohl(*p++);
90 	if (flavor != RPC_AUTH_NULL) {
91 		printk("RPC: bad verf flavor: %u\n", flavor);
92 		return ERR_PTR(-EIO);
93 	}
94 
95 	size = ntohl(*p++);
96 	if (size != 0) {
97 		printk("RPC: bad verf size: %u\n", size);
98 		return ERR_PTR(-EIO);
99 	}
100 
101 	return p;
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_ops		= &authnull_ops,
118 	.au_flavor	= RPC_AUTH_NULL,
119 	.au_count	= REFCOUNT_INIT(1),
120 };
121 
122 static
123 const struct rpc_credops null_credops = {
124 	.cr_name	= "AUTH_NULL",
125 	.crdestroy	= nul_destroy_cred,
126 	.crmatch	= nul_match,
127 	.crmarshal	= nul_marshal,
128 	.crrefresh	= nul_refresh,
129 	.crvalidate	= nul_validate,
130 };
131 
132 static
133 struct rpc_cred null_cred = {
134 	.cr_lru		= LIST_HEAD_INIT(null_cred.cr_lru),
135 	.cr_auth	= &null_auth,
136 	.cr_ops		= &null_credops,
137 	.cr_count	= REFCOUNT_INIT(2),
138 	.cr_flags	= 1UL << RPCAUTH_CRED_UPTODATE,
139 };
140