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#include <trace/events/sunrpc.h>
 23
 24#include "sunrpc.h"
 25
 26#define RPCDBG_FACILITY	RPCDBG_AUTH
 27
 28
 29/*
 30 * Table of authenticators
 31 */
 32extern struct auth_ops svcauth_null;
 33extern struct auth_ops svcauth_unix;
 34extern struct auth_ops svcauth_tls;
 35
 36static struct auth_ops __rcu *authtab[RPC_AUTH_MAXFLAVOR] = {
 37	[RPC_AUTH_NULL] = (struct auth_ops __force __rcu *)&svcauth_null,
 38	[RPC_AUTH_UNIX] = (struct auth_ops __force __rcu *)&svcauth_unix,
 39	[RPC_AUTH_TLS]  = (struct auth_ops __force __rcu *)&svcauth_tls,
 40};
 41
 42static struct auth_ops *
 43svc_get_auth_ops(rpc_authflavor_t flavor)
 44{
 45	struct auth_ops		*aops;
 46
 47	if (flavor >= RPC_AUTH_MAXFLAVOR)
 48		return NULL;
 49	rcu_read_lock();
 50	aops = rcu_dereference(authtab[flavor]);
 51	if (aops != NULL && !try_module_get(aops->owner))
 52		aops = NULL;
 53	rcu_read_unlock();
 54	return aops;
 55}
 56
 57static void
 58svc_put_auth_ops(struct auth_ops *aops)
 59{
 60	module_put(aops->owner);
 61}
 62
 63int
 64svc_authenticate(struct svc_rqst *rqstp)
 65{
 66	rpc_authflavor_t	flavor;
 67	struct auth_ops		*aops;
 68
 69	rqstp->rq_auth_stat = rpc_auth_ok;
 70
 71	flavor = svc_getnl(&rqstp->rq_arg.head[0]);
 72
 73	dprintk("svc: svc_authenticate (%d)\n", flavor);
 74
 75	aops = svc_get_auth_ops(flavor);
 76	if (aops == NULL) {
 77		rqstp->rq_auth_stat = rpc_autherr_badcred;
 78		return SVC_DENIED;
 79	}
 80
 81	rqstp->rq_auth_slack = 0;
 82	init_svc_cred(&rqstp->rq_cred);
 83
 84	rqstp->rq_authop = aops;
 85	return aops->accept(rqstp);
 86}
 87EXPORT_SYMBOL_GPL(svc_authenticate);
 88
 89int svc_set_client(struct svc_rqst *rqstp)
 90{
 91	rqstp->rq_client = NULL;
 92	return rqstp->rq_authop->set_client(rqstp);
 93}
 94EXPORT_SYMBOL_GPL(svc_set_client);
 95
 96/* A request, which was authenticated, has now executed.
 97 * Time to finalise the credentials and verifier
 98 * and release and resources
 99 */
100int svc_authorise(struct svc_rqst *rqstp)
101{
102	struct auth_ops *aops = rqstp->rq_authop;
103	int rv = 0;
104
105	rqstp->rq_authop = NULL;
106
107	if (aops) {
108		rv = aops->release(rqstp);
109		svc_put_auth_ops(aops);
110	}
111	return rv;
112}
113
114int
115svc_auth_register(rpc_authflavor_t flavor, struct auth_ops *aops)
116{
117	struct auth_ops *old;
118	int rv = -EINVAL;
119
120	if (flavor < RPC_AUTH_MAXFLAVOR) {
121		old = cmpxchg((struct auth_ops ** __force)&authtab[flavor], NULL, aops);
122		if (old == NULL || old == aops)
123			rv = 0;
124	}
125	return rv;
126}
127EXPORT_SYMBOL_GPL(svc_auth_register);
128
129void
130svc_auth_unregister(rpc_authflavor_t flavor)
131{
132	if (flavor < RPC_AUTH_MAXFLAVOR)
133		rcu_assign_pointer(authtab[flavor], NULL);
134}
135EXPORT_SYMBOL_GPL(svc_auth_unregister);
136
137/**************************************************
138 * 'auth_domains' are stored in a hash table indexed by name.
139 * When the last reference to an 'auth_domain' is dropped,
140 * the object is unhashed and freed.
141 * If auth_domain_lookup fails to find an entry, it will return
142 * it's second argument 'new'.  If this is non-null, it will
143 * have been atomically linked into the table.
144 */
145
146#define	DN_HASHBITS	6
147#define	DN_HASHMAX	(1<<DN_HASHBITS)
148
149static struct hlist_head	auth_domain_table[DN_HASHMAX];
150static DEFINE_SPINLOCK(auth_domain_lock);
151
152static void auth_domain_release(struct kref *kref)
153	__releases(&auth_domain_lock)
154{
155	struct auth_domain *dom = container_of(kref, struct auth_domain, ref);
156
157	hlist_del_rcu(&dom->hash);
158	dom->flavour->domain_release(dom);
159	spin_unlock(&auth_domain_lock);
160}
161
162void auth_domain_put(struct auth_domain *dom)
163{
164	kref_put_lock(&dom->ref, auth_domain_release, &auth_domain_lock);
165}
166EXPORT_SYMBOL_GPL(auth_domain_put);
167
168struct auth_domain *
169auth_domain_lookup(char *name, struct auth_domain *new)
170{
171	struct auth_domain *hp;
172	struct hlist_head *head;
173
174	head = &auth_domain_table[hash_str(name, DN_HASHBITS)];
175
176	spin_lock(&auth_domain_lock);
177
178	hlist_for_each_entry(hp, head, hash) {
179		if (strcmp(hp->name, name)==0) {
180			kref_get(&hp->ref);
181			spin_unlock(&auth_domain_lock);
182			return hp;
183		}
184	}
185	if (new)
186		hlist_add_head_rcu(&new->hash, head);
187	spin_unlock(&auth_domain_lock);
188	return new;
189}
190EXPORT_SYMBOL_GPL(auth_domain_lookup);
191
192struct auth_domain *auth_domain_find(char *name)
193{
194	struct auth_domain *hp;
195	struct hlist_head *head;
196
197	head = &auth_domain_table[hash_str(name, DN_HASHBITS)];
198
199	rcu_read_lock();
200	hlist_for_each_entry_rcu(hp, head, hash) {
201		if (strcmp(hp->name, name)==0) {
202			if (!kref_get_unless_zero(&hp->ref))
203				hp = NULL;
204			rcu_read_unlock();
205			return hp;
206		}
207	}
208	rcu_read_unlock();
209	return NULL;
210}
211EXPORT_SYMBOL_GPL(auth_domain_find);
212
213/**
214 * auth_domain_cleanup - check that the auth_domain table is empty
215 *
216 * On module unload the auth_domain_table must be empty.  To make it
217 * easier to catch bugs which don't clean up domains properly, we
218 * warn if anything remains in the table at cleanup time.
219 *
220 * Note that we cannot proactively remove the domains at this stage.
221 * The ->release() function might be in a module that has already been
222 * unloaded.
223 */
224
225void auth_domain_cleanup(void)
226{
227	int h;
228	struct auth_domain *hp;
229
230	for (h = 0; h < DN_HASHMAX; h++)
231		hlist_for_each_entry(hp, &auth_domain_table[h], hash)
232			pr_warn("svc: domain %s still present at module unload.\n",
233				hp->name);
234}

  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);