1 /*
2  * linux/net/sunrpc/rpcauth_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/slab.h>
11 #include <linux/socket.h>
12 #include <linux/in.h>
13 #include <linux/utsname.h>
14 #include <linux/sunrpc/clnt.h>
15 
16 #ifdef RPC_DEBUG
17 # define RPCDBG_FACILITY	RPCDBG_AUTH
18 #endif
19 
20 static struct rpc_credops	null_credops;
21 
22 static struct rpc_auth *
nul_create(struct rpc_clnt * clnt)23 nul_create(struct rpc_clnt *clnt)
24 {
25 	struct rpc_auth	*auth;
26 
27 	dprintk("RPC: creating NULL authenticator for client %p\n", clnt);
28 	if (!(auth = (struct rpc_auth *) rpc_allocate(0, sizeof(*auth))))
29 		return NULL;
30 	auth->au_cslack = 4;
31 	auth->au_rslack = 2;
32 	auth->au_ops = &authnull_ops;
33 	auth->au_expire = 1800 * HZ;
34 	rpcauth_init_credcache(auth);
35 
36 	return (struct rpc_auth *) auth;
37 }
38 
39 static void
nul_destroy(struct rpc_auth * auth)40 nul_destroy(struct rpc_auth *auth)
41 {
42 	dprintk("RPC: destroying NULL authenticator %p\n", auth);
43 	rpcauth_free_credcache(auth);
44 	rpc_free(auth);
45 }
46 
47 /*
48  * Create NULL creds for current process
49  */
50 static struct rpc_cred *
nul_create_cred(int flags)51 nul_create_cred(int flags)
52 {
53 	struct rpc_cred	*cred;
54 
55 	if (!(cred = (struct rpc_cred *) rpc_allocate(flags, sizeof(*cred))))
56 		return NULL;
57 	atomic_set(&cred->cr_count, 0);
58 	cred->cr_flags = RPCAUTH_CRED_UPTODATE;
59 	cred->cr_uid = current->uid;
60 	cred->cr_ops = &null_credops;
61 
62 	return cred;
63 }
64 
65 /*
66  * Destroy cred handle.
67  */
68 static void
nul_destroy_cred(struct rpc_cred * cred)69 nul_destroy_cred(struct rpc_cred *cred)
70 {
71 	rpc_free(cred);
72 }
73 
74 /*
75  * Match cred handle against current process
76  */
77 static int
nul_match(struct rpc_cred * cred,int taskflags)78 nul_match(struct rpc_cred *cred, int taskflags)
79 {
80 	return 1;
81 }
82 
83 /*
84  * Marshal credential.
85  */
86 static u32 *
nul_marshal(struct rpc_task * task,u32 * p,int ruid)87 nul_marshal(struct rpc_task *task, u32 *p, int ruid)
88 {
89 	*p++ = htonl(RPC_AUTH_NULL);
90 	*p++ = 0;
91 	*p++ = htonl(RPC_AUTH_NULL);
92 	*p++ = 0;
93 
94 	return p;
95 }
96 
97 /*
98  * Refresh credential. This is a no-op for AUTH_NULL
99  */
100 static int
nul_refresh(struct rpc_task * task)101 nul_refresh(struct rpc_task *task)
102 {
103 	return task->tk_status = -EACCES;
104 }
105 
106 static u32 *
nul_validate(struct rpc_task * task,u32 * p)107 nul_validate(struct rpc_task *task, u32 *p)
108 {
109 	u32		n = ntohl(*p++);
110 
111 	if (n != RPC_AUTH_NULL) {
112 		printk("RPC: bad verf flavor: %ld\n", (unsigned long) n);
113 		return NULL;
114 	}
115 	if ((n = ntohl(*p++)) != 0) {
116 		printk("RPC: bad verf size: %ld\n", (unsigned long) n);
117 		return NULL;
118 	}
119 
120 	return p;
121 }
122 
123 struct rpc_authops	authnull_ops = {
124 	RPC_AUTH_NULL,
125 #ifdef RPC_DEBUG
126 	"NULL",
127 #endif
128 	nul_create,
129 	nul_destroy,
130 	nul_create_cred
131 };
132 
133 static
134 struct rpc_credops	null_credops = {
135 	nul_destroy_cred,
136 	nul_match,
137 	nul_marshal,
138 	nul_refresh,
139 	nul_validate
140 };
141