blob: 1619211f0960afbfdac1a22617a3e74f437672e1 [file] [log] [blame]
Thomas Gleixner457c8992019-05-19 13:08:55 +01001// SPDX-License-Identifier: GPL-2.0-only
Linus Torvalds1da177e2005-04-16 15:20:36 -07002/*
3 * linux/net/sunrpc/svcauth.c
4 *
5 * The generic interface for RPC authentication on the server side.
YOSHIFUJI Hideakicca51722007-02-09 15:38:13 -08006 *
Linus Torvalds1da177e2005-04-16 15:20:36 -07007 * 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>
Linus Torvalds1da177e2005-04-16 15:20:36 -070014#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
Chuck Leverff27e9f2019-10-24 09:34:10 -040022#include <trace/events/sunrpc.h>
23
NeilBrownf45db2b2020-05-22 12:01:32 +100024#include "sunrpc.h"
25
Linus Torvalds1da177e2005-04-16 15:20:36 -070026#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;
Chuck Lever74aaf962022-02-22 13:10:52 -050034extern struct auth_ops svcauth_tls;
Linus Torvalds1da177e2005-04-16 15:20:36 -070035
Trond Myklebust30382d62018-10-01 10:41:43 -040036static 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,
Chuck Lever74aaf962022-02-22 13:10:52 -050039 [RPC_AUTH_TLS] = (struct auth_ops __force __rcu *)&svcauth_tls,
Linus Torvalds1da177e2005-04-16 15:20:36 -070040};
41
Trond Myklebust30382d62018-10-01 10:41:43 -040042static 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
Chuck Lever78c542f2023-07-29 20:58:54 -040063/**
64 * svc_authenticate - Initialize an outgoing credential
65 * @rqstp: RPC execution context
66 *
67 * Return values:
68 * %SVC_OK: XDR encoding of the result can begin
69 * %SVC_DENIED: Credential or verifier is not valid
70 * %SVC_GARBAGE: Failed to decode credential or verifier
71 * %SVC_COMPLETE: GSS context lifetime event; no further action
72 * %SVC_DROP: Drop this request; no further action
73 * %SVC_CLOSE: Like drop, but also close transport connection
74 */
75enum svc_auth_status svc_authenticate(struct svc_rqst *rqstp)
Linus Torvalds1da177e2005-04-16 15:20:36 -070076{
Chuck Lever6898b472023-01-02 12:07:32 -050077 struct auth_ops *aops;
78 u32 flavor;
Linus Torvalds1da177e2005-04-16 15:20:36 -070079
Chuck Lever438623a2021-07-15 15:52:06 -040080 rqstp->rq_auth_stat = rpc_auth_ok;
Linus Torvalds1da177e2005-04-16 15:20:36 -070081
Chuck Lever6898b472023-01-02 12:07:32 -050082 /*
83 * Decode the Call credential's flavor field. The credential's
84 * body field is decoded in the chosen ->accept method below.
85 */
86 if (xdr_stream_decode_u32(&rqstp->rq_arg_stream, &flavor) < 0)
87 return SVC_GARBAGE;
Linus Torvalds1da177e2005-04-16 15:20:36 -070088
Trond Myklebust30382d62018-10-01 10:41:43 -040089 aops = svc_get_auth_ops(flavor);
90 if (aops == NULL) {
Chuck Lever438623a2021-07-15 15:52:06 -040091 rqstp->rq_auth_stat = rpc_autherr_badcred;
Linus Torvalds1da177e2005-04-16 15:20:36 -070092 return SVC_DENIED;
93 }
Linus Torvalds1da177e2005-04-16 15:20:36 -070094
J. Bruce Fieldsa5cddc82014-05-12 18:10:58 -040095 rqstp->rq_auth_slack = 0;
J. Bruce Fields6496500c2015-11-20 15:45:35 -050096 init_svc_cred(&rqstp->rq_cred);
J. Bruce Fieldsa5cddc82014-05-12 18:10:58 -040097
Linus Torvalds1da177e2005-04-16 15:20:36 -070098 rqstp->rq_authop = aops;
Chuck Lever438623a2021-07-15 15:52:06 -040099 return aops->accept(rqstp);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700100}
Trond Myklebust24c37672008-12-23 16:30:12 -0500101EXPORT_SYMBOL_GPL(svc_authenticate);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700102
Chuck Lever78c542f2023-07-29 20:58:54 -0400103/**
104 * svc_set_client - Assign an appropriate 'auth_domain' as the client
105 * @rqstp: RPC execution context
106 *
107 * Return values:
108 * %SVC_OK: Client was found and assigned
109 * %SVC_DENY: Client was explicitly denied
110 * %SVC_DROP: Ignore this request
111 * %SVC_CLOSE: Ignore this request and close the connection
112 */
113enum svc_auth_status svc_set_client(struct svc_rqst *rqstp)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700114{
J. Bruce Fields6496500c2015-11-20 15:45:35 -0500115 rqstp->rq_client = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700116 return rqstp->rq_authop->set_client(rqstp);
117}
Trond Myklebust24c37672008-12-23 16:30:12 -0500118EXPORT_SYMBOL_GPL(svc_set_client);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700119
Chuck Lever78c542f2023-07-29 20:58:54 -0400120/**
121 * svc_authorise - Finalize credentials/verifier and release resources
122 * @rqstp: RPC execution context
123 *
124 * Returns zero on success, or a negative errno.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700125 */
126int svc_authorise(struct svc_rqst *rqstp)
127{
128 struct auth_ops *aops = rqstp->rq_authop;
129 int rv = 0;
130
131 rqstp->rq_authop = NULL;
YOSHIFUJI Hideakicca51722007-02-09 15:38:13 -0800132
Linus Torvalds1da177e2005-04-16 15:20:36 -0700133 if (aops) {
134 rv = aops->release(rqstp);
Trond Myklebust30382d62018-10-01 10:41:43 -0400135 svc_put_auth_ops(aops);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700136 }
137 return rv;
138}
139
140int
141svc_auth_register(rpc_authflavor_t flavor, struct auth_ops *aops)
142{
Trond Myklebust30382d62018-10-01 10:41:43 -0400143 struct auth_ops *old;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700144 int rv = -EINVAL;
Trond Myklebust30382d62018-10-01 10:41:43 -0400145
146 if (flavor < RPC_AUTH_MAXFLAVOR) {
147 old = cmpxchg((struct auth_ops ** __force)&authtab[flavor], NULL, aops);
148 if (old == NULL || old == aops)
149 rv = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700150 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700151 return rv;
152}
Trond Myklebust24c37672008-12-23 16:30:12 -0500153EXPORT_SYMBOL_GPL(svc_auth_register);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700154
155void
156svc_auth_unregister(rpc_authflavor_t flavor)
157{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700158 if (flavor < RPC_AUTH_MAXFLAVOR)
Trond Myklebust30382d62018-10-01 10:41:43 -0400159 rcu_assign_pointer(authtab[flavor], NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700160}
Trond Myklebust24c37672008-12-23 16:30:12 -0500161EXPORT_SYMBOL_GPL(svc_auth_unregister);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700162
Chuck Leverdeb70422023-11-17 17:14:27 -0500163/**
164 * svc_auth_flavor - return RPC transaction's RPC_AUTH flavor
165 * @rqstp: RPC transaction context
166 *
167 * Returns an RPC flavor or GSS pseudoflavor.
168 */
169rpc_authflavor_t svc_auth_flavor(struct svc_rqst *rqstp)
170{
171 struct auth_ops *aops = rqstp->rq_authop;
172
173 if (!aops->pseudoflavor)
174 return aops->flavour;
175 return aops->pseudoflavor(rqstp);
176}
177EXPORT_SYMBOL_GPL(svc_auth_flavor);
178
Linus Torvalds1da177e2005-04-16 15:20:36 -0700179/**************************************************
NeilBrownefc36aa2006-03-27 01:14:59 -0800180 * 'auth_domains' are stored in a hash table indexed by name.
181 * When the last reference to an 'auth_domain' is dropped,
182 * the object is unhashed and freed.
183 * If auth_domain_lookup fails to find an entry, it will return
184 * it's second argument 'new'. If this is non-null, it will
185 * have been atomically linked into the table.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700186 */
187
Linus Torvalds1da177e2005-04-16 15:20:36 -0700188#define DN_HASHBITS 6
189#define DN_HASHMAX (1<<DN_HASHBITS)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700190
NeilBrownefc36aa2006-03-27 01:14:59 -0800191static struct hlist_head auth_domain_table[DN_HASHMAX];
Fabian Frederick3eb15f22016-12-04 13:45:28 +0100192static DEFINE_SPINLOCK(auth_domain_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700193
Peter Zijlstra0a13cd12016-11-14 18:03:11 +0100194static void auth_domain_release(struct kref *kref)
Trond Myklebust608a0ab2018-10-01 10:41:44 -0400195 __releases(&auth_domain_lock)
Peter Zijlstra0a13cd12016-11-14 18:03:11 +0100196{
197 struct auth_domain *dom = container_of(kref, struct auth_domain, ref);
198
Trond Myklebust608a0ab2018-10-01 10:41:44 -0400199 hlist_del_rcu(&dom->hash);
Peter Zijlstra0a13cd12016-11-14 18:03:11 +0100200 dom->flavour->domain_release(dom);
201 spin_unlock(&auth_domain_lock);
202}
203
Linus Torvalds1da177e2005-04-16 15:20:36 -0700204void auth_domain_put(struct auth_domain *dom)
205{
Peter Zijlstra0a13cd12016-11-14 18:03:11 +0100206 kref_put_lock(&dom->ref, auth_domain_release, &auth_domain_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700207}
Trond Myklebust24c37672008-12-23 16:30:12 -0500208EXPORT_SYMBOL_GPL(auth_domain_put);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700209
210struct auth_domain *
NeilBrownefc36aa2006-03-27 01:14:59 -0800211auth_domain_lookup(char *name, struct auth_domain *new)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700212{
NeilBrownefc36aa2006-03-27 01:14:59 -0800213 struct auth_domain *hp;
214 struct hlist_head *head;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700215
NeilBrownefc36aa2006-03-27 01:14:59 -0800216 head = &auth_domain_table[hash_str(name, DN_HASHBITS)];
217
218 spin_lock(&auth_domain_lock);
219
Sasha Levinb67bfe02013-02-27 17:06:00 -0800220 hlist_for_each_entry(hp, head, hash) {
NeilBrownefc36aa2006-03-27 01:14:59 -0800221 if (strcmp(hp->name, name)==0) {
222 kref_get(&hp->ref);
223 spin_unlock(&auth_domain_lock);
224 return hp;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700225 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700226 }
Neil Brownd6740df2006-10-29 22:46:45 -0800227 if (new)
Trond Myklebust608a0ab2018-10-01 10:41:44 -0400228 hlist_add_head_rcu(&new->hash, head);
NeilBrownefc36aa2006-03-27 01:14:59 -0800229 spin_unlock(&auth_domain_lock);
230 return new;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700231}
Trond Myklebust24c37672008-12-23 16:30:12 -0500232EXPORT_SYMBOL_GPL(auth_domain_lookup);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700233
234struct auth_domain *auth_domain_find(char *name)
235{
Trond Myklebust608a0ab2018-10-01 10:41:44 -0400236 struct auth_domain *hp;
237 struct hlist_head *head;
238
239 head = &auth_domain_table[hash_str(name, DN_HASHBITS)];
240
241 rcu_read_lock();
242 hlist_for_each_entry_rcu(hp, head, hash) {
243 if (strcmp(hp->name, name)==0) {
244 if (!kref_get_unless_zero(&hp->ref))
245 hp = NULL;
246 rcu_read_unlock();
247 return hp;
248 }
249 }
250 rcu_read_unlock();
251 return NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700252}
Trond Myklebust24c37672008-12-23 16:30:12 -0500253EXPORT_SYMBOL_GPL(auth_domain_find);
NeilBrownf45db2b2020-05-22 12:01:32 +1000254
255/**
256 * auth_domain_cleanup - check that the auth_domain table is empty
257 *
258 * On module unload the auth_domain_table must be empty. To make it
259 * easier to catch bugs which don't clean up domains properly, we
260 * warn if anything remains in the table at cleanup time.
261 *
262 * Note that we cannot proactively remove the domains at this stage.
263 * The ->release() function might be in a module that has already been
264 * unloaded.
265 */
266
267void auth_domain_cleanup(void)
268{
269 int h;
270 struct auth_domain *hp;
271
272 for (h = 0; h < DN_HASHMAX; h++)
273 hlist_for_each_entry(hp, &auth_domain_table[h], hash)
274 pr_warn("svc: domain %s still present at module unload.\n",
275 hp->name);
276}