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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * linux/net/sunrpc/svcauth.c
4 *
5 * The generic interface for RPC authentication on the server side.
6 *
7 * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
8 *
9 * CHANGES
10 * 19-Apr-2000 Chris Evans - Security fix
11 */
12
13#include <linux/types.h>
14#include <linux/module.h>
15#include <linux/sunrpc/types.h>
16#include <linux/sunrpc/xdr.h>
17#include <linux/sunrpc/svcsock.h>
18#include <linux/sunrpc/svcauth.h>
19#include <linux/err.h>
20#include <linux/hash.h>
21
22#define RPCDBG_FACILITY RPCDBG_AUTH
23
24
25/*
26 * Table of authenticators
27 */
28extern struct auth_ops svcauth_null;
29extern struct auth_ops svcauth_unix;
30
31static struct auth_ops __rcu *authtab[RPC_AUTH_MAXFLAVOR] = {
32 [RPC_AUTH_NULL] = (struct auth_ops __force __rcu *)&svcauth_null,
33 [RPC_AUTH_UNIX] = (struct auth_ops __force __rcu *)&svcauth_unix,
34};
35
36static struct auth_ops *
37svc_get_auth_ops(rpc_authflavor_t flavor)
38{
39 struct auth_ops *aops;
40
41 if (flavor >= RPC_AUTH_MAXFLAVOR)
42 return NULL;
43 rcu_read_lock();
44 aops = rcu_dereference(authtab[flavor]);
45 if (aops != NULL && !try_module_get(aops->owner))
46 aops = NULL;
47 rcu_read_unlock();
48 return aops;
49}
50
51static void
52svc_put_auth_ops(struct auth_ops *aops)
53{
54 module_put(aops->owner);
55}
56
57int
58svc_authenticate(struct svc_rqst *rqstp, __be32 *authp)
59{
60 rpc_authflavor_t flavor;
61 struct auth_ops *aops;
62
63 *authp = rpc_auth_ok;
64
65 flavor = svc_getnl(&rqstp->rq_arg.head[0]);
66
67 dprintk("svc: svc_authenticate (%d)\n", flavor);
68
69 aops = svc_get_auth_ops(flavor);
70 if (aops == NULL) {
71 *authp = rpc_autherr_badcred;
72 return SVC_DENIED;
73 }
74
75 rqstp->rq_auth_slack = 0;
76 init_svc_cred(&rqstp->rq_cred);
77
78 rqstp->rq_authop = aops;
79 return aops->accept(rqstp, authp);
80}
81EXPORT_SYMBOL_GPL(svc_authenticate);
82
83int svc_set_client(struct svc_rqst *rqstp)
84{
85 rqstp->rq_client = NULL;
86 return rqstp->rq_authop->set_client(rqstp);
87}
88EXPORT_SYMBOL_GPL(svc_set_client);
89
90/* A request, which was authenticated, has now executed.
91 * Time to finalise the credentials and verifier
92 * and release and resources
93 */
94int svc_authorise(struct svc_rqst *rqstp)
95{
96 struct auth_ops *aops = rqstp->rq_authop;
97 int rv = 0;
98
99 rqstp->rq_authop = NULL;
100
101 if (aops) {
102 rv = aops->release(rqstp);
103 svc_put_auth_ops(aops);
104 }
105 return rv;
106}
107
108int
109svc_auth_register(rpc_authflavor_t flavor, struct auth_ops *aops)
110{
111 struct auth_ops *old;
112 int rv = -EINVAL;
113
114 if (flavor < RPC_AUTH_MAXFLAVOR) {
115 old = cmpxchg((struct auth_ops ** __force)&authtab[flavor], NULL, aops);
116 if (old == NULL || old == aops)
117 rv = 0;
118 }
119 return rv;
120}
121EXPORT_SYMBOL_GPL(svc_auth_register);
122
123void
124svc_auth_unregister(rpc_authflavor_t flavor)
125{
126 if (flavor < RPC_AUTH_MAXFLAVOR)
127 rcu_assign_pointer(authtab[flavor], NULL);
128}
129EXPORT_SYMBOL_GPL(svc_auth_unregister);
130
131/**************************************************
132 * 'auth_domains' are stored in a hash table indexed by name.
133 * When the last reference to an 'auth_domain' is dropped,
134 * the object is unhashed and freed.
135 * If auth_domain_lookup fails to find an entry, it will return
136 * it's second argument 'new'. If this is non-null, it will
137 * have been atomically linked into the table.
138 */
139
140#define DN_HASHBITS 6
141#define DN_HASHMAX (1<<DN_HASHBITS)
142
143static struct hlist_head auth_domain_table[DN_HASHMAX];
144static DEFINE_SPINLOCK(auth_domain_lock);
145
146static void auth_domain_release(struct kref *kref)
147 __releases(&auth_domain_lock)
148{
149 struct auth_domain *dom = container_of(kref, struct auth_domain, ref);
150
151 hlist_del_rcu(&dom->hash);
152 dom->flavour->domain_release(dom);
153 spin_unlock(&auth_domain_lock);
154}
155
156void auth_domain_put(struct auth_domain *dom)
157{
158 kref_put_lock(&dom->ref, auth_domain_release, &auth_domain_lock);
159}
160EXPORT_SYMBOL_GPL(auth_domain_put);
161
162struct auth_domain *
163auth_domain_lookup(char *name, struct auth_domain *new)
164{
165 struct auth_domain *hp;
166 struct hlist_head *head;
167
168 head = &auth_domain_table[hash_str(name, DN_HASHBITS)];
169
170 spin_lock(&auth_domain_lock);
171
172 hlist_for_each_entry(hp, head, hash) {
173 if (strcmp(hp->name, name)==0) {
174 kref_get(&hp->ref);
175 spin_unlock(&auth_domain_lock);
176 return hp;
177 }
178 }
179 if (new)
180 hlist_add_head_rcu(&new->hash, head);
181 spin_unlock(&auth_domain_lock);
182 return new;
183}
184EXPORT_SYMBOL_GPL(auth_domain_lookup);
185
186struct auth_domain *auth_domain_find(char *name)
187{
188 struct auth_domain *hp;
189 struct hlist_head *head;
190
191 head = &auth_domain_table[hash_str(name, DN_HASHBITS)];
192
193 rcu_read_lock();
194 hlist_for_each_entry_rcu(hp, head, hash) {
195 if (strcmp(hp->name, name)==0) {
196 if (!kref_get_unless_zero(&hp->ref))
197 hp = NULL;
198 rcu_read_unlock();
199 return hp;
200 }
201 }
202 rcu_read_unlock();
203 return NULL;
204}
205EXPORT_SYMBOL_GPL(auth_domain_find);
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * linux/net/sunrpc/svcauth.c
4 *
5 * The generic interface for RPC authentication on the server side.
6 *
7 * Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
8 *
9 * CHANGES
10 * 19-Apr-2000 Chris Evans - Security fix
11 */
12
13#include <linux/types.h>
14#include <linux/module.h>
15#include <linux/sunrpc/types.h>
16#include <linux/sunrpc/xdr.h>
17#include <linux/sunrpc/svcsock.h>
18#include <linux/sunrpc/svcauth.h>
19#include <linux/err.h>
20#include <linux/hash.h>
21
22#define RPCDBG_FACILITY RPCDBG_AUTH
23
24
25/*
26 * Table of authenticators
27 */
28extern struct auth_ops svcauth_null;
29extern struct auth_ops svcauth_unix;
30
31static struct auth_ops __rcu *authtab[RPC_AUTH_MAXFLAVOR] = {
32 [RPC_AUTH_NULL] = (struct auth_ops __force __rcu *)&svcauth_null,
33 [RPC_AUTH_UNIX] = (struct auth_ops __force __rcu *)&svcauth_unix,
34};
35
36static struct auth_ops *
37svc_get_auth_ops(rpc_authflavor_t flavor)
38{
39 struct auth_ops *aops;
40
41 if (flavor >= RPC_AUTH_MAXFLAVOR)
42 return NULL;
43 rcu_read_lock();
44 aops = rcu_dereference(authtab[flavor]);
45 if (aops != NULL && !try_module_get(aops->owner))
46 aops = NULL;
47 rcu_read_unlock();
48 return aops;
49}
50
51static void
52svc_put_auth_ops(struct auth_ops *aops)
53{
54 module_put(aops->owner);
55}
56
57int
58svc_authenticate(struct svc_rqst *rqstp, __be32 *authp)
59{
60 rpc_authflavor_t flavor;
61 struct auth_ops *aops;
62
63 *authp = rpc_auth_ok;
64
65 flavor = svc_getnl(&rqstp->rq_arg.head[0]);
66
67 dprintk("svc: svc_authenticate (%d)\n", flavor);
68
69 aops = svc_get_auth_ops(flavor);
70 if (aops == NULL) {
71 *authp = rpc_autherr_badcred;
72 return SVC_DENIED;
73 }
74
75 rqstp->rq_auth_slack = 0;
76 init_svc_cred(&rqstp->rq_cred);
77
78 rqstp->rq_authop = aops;
79 return aops->accept(rqstp, authp);
80}
81EXPORT_SYMBOL_GPL(svc_authenticate);
82
83int svc_set_client(struct svc_rqst *rqstp)
84{
85 rqstp->rq_client = NULL;
86 return rqstp->rq_authop->set_client(rqstp);
87}
88EXPORT_SYMBOL_GPL(svc_set_client);
89
90/* A request, which was authenticated, has now executed.
91 * Time to finalise the credentials and verifier
92 * and release and resources
93 */
94int svc_authorise(struct svc_rqst *rqstp)
95{
96 struct auth_ops *aops = rqstp->rq_authop;
97 int rv = 0;
98
99 rqstp->rq_authop = NULL;
100
101 if (aops) {
102 rv = aops->release(rqstp);
103 svc_put_auth_ops(aops);
104 }
105 return rv;
106}
107
108int
109svc_auth_register(rpc_authflavor_t flavor, struct auth_ops *aops)
110{
111 struct auth_ops *old;
112 int rv = -EINVAL;
113
114 if (flavor < RPC_AUTH_MAXFLAVOR) {
115 old = cmpxchg((struct auth_ops ** __force)&authtab[flavor], NULL, aops);
116 if (old == NULL || old == aops)
117 rv = 0;
118 }
119 return rv;
120}
121EXPORT_SYMBOL_GPL(svc_auth_register);
122
123void
124svc_auth_unregister(rpc_authflavor_t flavor)
125{
126 if (flavor < RPC_AUTH_MAXFLAVOR)
127 rcu_assign_pointer(authtab[flavor], NULL);
128}
129EXPORT_SYMBOL_GPL(svc_auth_unregister);
130
131/**************************************************
132 * 'auth_domains' are stored in a hash table indexed by name.
133 * When the last reference to an 'auth_domain' is dropped,
134 * the object is unhashed and freed.
135 * If auth_domain_lookup fails to find an entry, it will return
136 * it's second argument 'new'. If this is non-null, it will
137 * have been atomically linked into the table.
138 */
139
140#define DN_HASHBITS 6
141#define DN_HASHMAX (1<<DN_HASHBITS)
142
143static struct hlist_head auth_domain_table[DN_HASHMAX];
144static DEFINE_SPINLOCK(auth_domain_lock);
145
146static void auth_domain_release(struct kref *kref)
147 __releases(&auth_domain_lock)
148{
149 struct auth_domain *dom = container_of(kref, struct auth_domain, ref);
150
151 hlist_del_rcu(&dom->hash);
152 dom->flavour->domain_release(dom);
153 spin_unlock(&auth_domain_lock);
154}
155
156void auth_domain_put(struct auth_domain *dom)
157{
158 kref_put_lock(&dom->ref, auth_domain_release, &auth_domain_lock);
159}
160EXPORT_SYMBOL_GPL(auth_domain_put);
161
162struct auth_domain *
163auth_domain_lookup(char *name, struct auth_domain *new)
164{
165 struct auth_domain *hp;
166 struct hlist_head *head;
167
168 head = &auth_domain_table[hash_str(name, DN_HASHBITS)];
169
170 spin_lock(&auth_domain_lock);
171
172 hlist_for_each_entry(hp, head, hash) {
173 if (strcmp(hp->name, name)==0) {
174 kref_get(&hp->ref);
175 spin_unlock(&auth_domain_lock);
176 return hp;
177 }
178 }
179 if (new)
180 hlist_add_head_rcu(&new->hash, head);
181 spin_unlock(&auth_domain_lock);
182 return new;
183}
184EXPORT_SYMBOL_GPL(auth_domain_lookup);
185
186struct auth_domain *auth_domain_find(char *name)
187{
188 struct auth_domain *hp;
189 struct hlist_head *head;
190
191 head = &auth_domain_table[hash_str(name, DN_HASHBITS)];
192
193 rcu_read_lock();
194 hlist_for_each_entry_rcu(hp, head, hash) {
195 if (strcmp(hp->name, name)==0) {
196 if (!kref_get_unless_zero(&hp->ref))
197 hp = NULL;
198 rcu_read_unlock();
199 return hp;
200 }
201 }
202 rcu_read_unlock();
203 return NULL;
204}
205EXPORT_SYMBOL_GPL(auth_domain_find);