1/*
2 * linux/net/sunrpc/auth_null.c
3 *
4 * AUTH_NULL authentication. Really :-)
5 *
6 * Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de>
7 */
8
9#include <linux/types.h>
10#include <linux/module.h>
11#include <linux/sunrpc/clnt.h>
12
13#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
14# define RPCDBG_FACILITY	RPCDBG_AUTH
15#endif
16
17static struct rpc_auth null_auth;
18static struct rpc_cred null_cred;
19
20static struct rpc_auth *
21nul_create(struct rpc_auth_create_args *args, struct rpc_clnt *clnt)
22{
23	atomic_inc(&null_auth.au_count);
24	return &null_auth;
25}
26
27static void
28nul_destroy(struct rpc_auth *auth)
29{
30}
31
32/*
33 * Lookup NULL creds for current process
34 */
35static struct rpc_cred *
36nul_lookup_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags)
37{
38	if (flags & RPCAUTH_LOOKUP_RCU)
39		return &null_cred;
40	return get_rpccred(&null_cred);
41}
42
43/*
44 * Destroy cred handle.
45 */
46static void
47nul_destroy_cred(struct rpc_cred *cred)
48{
49}
50
51/*
52 * Match cred handle against current process
53 */
54static int
55nul_match(struct auth_cred *acred, struct rpc_cred *cred, int taskflags)
56{
57	return 1;
58}
59
60/*
61 * Marshal credential.
62 */
63static __be32 *
64nul_marshal(struct rpc_task *task, __be32 *p)
65{
66	*p++ = htonl(RPC_AUTH_NULL);
67	*p++ = 0;
68	*p++ = htonl(RPC_AUTH_NULL);
69	*p++ = 0;
70
71	return p;
72}
73
74/*
75 * Refresh credential. This is a no-op for AUTH_NULL
76 */
77static int
78nul_refresh(struct rpc_task *task)
79{
80	set_bit(RPCAUTH_CRED_UPTODATE, &task->tk_rqstp->rq_cred->cr_flags);
81	return 0;
82}
83
84static __be32 *
85nul_validate(struct rpc_task *task, __be32 *p)
86{
87	rpc_authflavor_t	flavor;
88	u32			size;
89
90	flavor = ntohl(*p++);
91	if (flavor != RPC_AUTH_NULL) {
92		printk("RPC: bad verf flavor: %u\n", flavor);
93		return ERR_PTR(-EIO);
94	}
95
96	size = ntohl(*p++);
97	if (size != 0) {
98		printk("RPC: bad verf size: %u\n", size);
99		return ERR_PTR(-EIO);
100	}
101
102	return p;
103}
104
105const struct rpc_authops authnull_ops = {
106	.owner		= THIS_MODULE,
107	.au_flavor	= RPC_AUTH_NULL,
108	.au_name	= "NULL",
109	.create		= nul_create,
110	.destroy	= nul_destroy,
111	.lookup_cred	= nul_lookup_cred,
112};
113
114static
115struct rpc_auth null_auth = {
116	.au_cslack	= 4,
117	.au_rslack	= 2,
118	.au_ops		= &authnull_ops,
119	.au_flavor	= RPC_AUTH_NULL,
120	.au_count	= ATOMIC_INIT(0),
121};
122
123static
124const struct rpc_credops null_credops = {
125	.cr_name	= "AUTH_NULL",
126	.crdestroy	= nul_destroy_cred,
127	.crbind		= rpcauth_generic_bind_cred,
128	.crmatch	= nul_match,
129	.crmarshal	= nul_marshal,
130	.crrefresh	= nul_refresh,
131	.crvalidate	= nul_validate,
132};
133
134static
135struct rpc_cred null_cred = {
136	.cr_lru		= LIST_HEAD_INIT(null_cred.cr_lru),
137	.cr_auth	= &null_auth,
138	.cr_ops		= &null_credops,
139	.cr_count	= ATOMIC_INIT(1),
140	.cr_flags	= 1UL << RPCAUTH_CRED_UPTODATE,
141#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
142	.cr_magic	= RPCAUTH_CRED_MAGIC,
143#endif
144};
145