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1/*
2 * Generic RPC credential
3 *
4 * Copyright (C) 2008, Trond Myklebust <Trond.Myklebust@netapp.com>
5 */
6
7#include <linux/err.h>
8#include <linux/slab.h>
9#include <linux/types.h>
10#include <linux/module.h>
11#include <linux/sched.h>
12#include <linux/sunrpc/auth.h>
13#include <linux/sunrpc/clnt.h>
14#include <linux/sunrpc/debug.h>
15#include <linux/sunrpc/sched.h>
16
17#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
18# define RPCDBG_FACILITY RPCDBG_AUTH
19#endif
20
21#define RPC_MACHINE_CRED_USERID GLOBAL_ROOT_UID
22#define RPC_MACHINE_CRED_GROUPID GLOBAL_ROOT_GID
23
24struct generic_cred {
25 struct rpc_cred gc_base;
26 struct auth_cred acred;
27};
28
29static struct rpc_auth generic_auth;
30static const struct rpc_credops generic_credops;
31
32/*
33 * Public call interface
34 */
35struct rpc_cred *rpc_lookup_cred(void)
36{
37 return rpcauth_lookupcred(&generic_auth, 0);
38}
39EXPORT_SYMBOL_GPL(rpc_lookup_cred);
40
41struct rpc_cred *rpc_lookup_cred_nonblock(void)
42{
43 return rpcauth_lookupcred(&generic_auth, RPCAUTH_LOOKUP_RCU);
44}
45EXPORT_SYMBOL_GPL(rpc_lookup_cred_nonblock);
46
47/*
48 * Public call interface for looking up machine creds.
49 */
50struct rpc_cred *rpc_lookup_machine_cred(const char *service_name)
51{
52 struct auth_cred acred = {
53 .uid = RPC_MACHINE_CRED_USERID,
54 .gid = RPC_MACHINE_CRED_GROUPID,
55 .principal = service_name,
56 .machine_cred = 1,
57 };
58
59 dprintk("RPC: looking up machine cred for service %s\n",
60 service_name);
61 return generic_auth.au_ops->lookup_cred(&generic_auth, &acred, 0);
62}
63EXPORT_SYMBOL_GPL(rpc_lookup_machine_cred);
64
65static struct rpc_cred *generic_bind_cred(struct rpc_task *task,
66 struct rpc_cred *cred, int lookupflags)
67{
68 struct rpc_auth *auth = task->tk_client->cl_auth;
69 struct auth_cred *acred = &container_of(cred, struct generic_cred, gc_base)->acred;
70
71 return auth->au_ops->lookup_cred(auth, acred, lookupflags);
72}
73
74/*
75 * Lookup generic creds for current process
76 */
77static struct rpc_cred *
78generic_lookup_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags)
79{
80 return rpcauth_lookup_credcache(&generic_auth, acred, flags);
81}
82
83static struct rpc_cred *
84generic_create_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags)
85{
86 struct generic_cred *gcred;
87
88 gcred = kmalloc(sizeof(*gcred), GFP_KERNEL);
89 if (gcred == NULL)
90 return ERR_PTR(-ENOMEM);
91
92 rpcauth_init_cred(&gcred->gc_base, acred, &generic_auth, &generic_credops);
93 gcred->gc_base.cr_flags = 1UL << RPCAUTH_CRED_UPTODATE;
94
95 gcred->acred.uid = acred->uid;
96 gcred->acred.gid = acred->gid;
97 gcred->acred.group_info = acred->group_info;
98 gcred->acred.ac_flags = 0;
99 if (gcred->acred.group_info != NULL)
100 get_group_info(gcred->acred.group_info);
101 gcred->acred.machine_cred = acred->machine_cred;
102 gcred->acred.principal = acred->principal;
103
104 dprintk("RPC: allocated %s cred %p for uid %d gid %d\n",
105 gcred->acred.machine_cred ? "machine" : "generic",
106 gcred,
107 from_kuid(&init_user_ns, acred->uid),
108 from_kgid(&init_user_ns, acred->gid));
109 return &gcred->gc_base;
110}
111
112static void
113generic_free_cred(struct rpc_cred *cred)
114{
115 struct generic_cred *gcred = container_of(cred, struct generic_cred, gc_base);
116
117 dprintk("RPC: generic_free_cred %p\n", gcred);
118 if (gcred->acred.group_info != NULL)
119 put_group_info(gcred->acred.group_info);
120 kfree(gcred);
121}
122
123static void
124generic_free_cred_callback(struct rcu_head *head)
125{
126 struct rpc_cred *cred = container_of(head, struct rpc_cred, cr_rcu);
127 generic_free_cred(cred);
128}
129
130static void
131generic_destroy_cred(struct rpc_cred *cred)
132{
133 call_rcu(&cred->cr_rcu, generic_free_cred_callback);
134}
135
136static int
137machine_cred_match(struct auth_cred *acred, struct generic_cred *gcred, int flags)
138{
139 if (!gcred->acred.machine_cred ||
140 gcred->acred.principal != acred->principal ||
141 !uid_eq(gcred->acred.uid, acred->uid) ||
142 !gid_eq(gcred->acred.gid, acred->gid))
143 return 0;
144 return 1;
145}
146
147/*
148 * Match credentials against current process creds.
149 */
150static int
151generic_match(struct auth_cred *acred, struct rpc_cred *cred, int flags)
152{
153 struct generic_cred *gcred = container_of(cred, struct generic_cred, gc_base);
154 int i;
155
156 if (acred->machine_cred)
157 return machine_cred_match(acred, gcred, flags);
158
159 if (!uid_eq(gcred->acred.uid, acred->uid) ||
160 !gid_eq(gcred->acred.gid, acred->gid) ||
161 gcred->acred.machine_cred != 0)
162 goto out_nomatch;
163
164 /* Optimisation in the case where pointers are identical... */
165 if (gcred->acred.group_info == acred->group_info)
166 goto out_match;
167
168 /* Slow path... */
169 if (gcred->acred.group_info->ngroups != acred->group_info->ngroups)
170 goto out_nomatch;
171 for (i = 0; i < gcred->acred.group_info->ngroups; i++) {
172 if (!gid_eq(GROUP_AT(gcred->acred.group_info, i),
173 GROUP_AT(acred->group_info, i)))
174 goto out_nomatch;
175 }
176out_match:
177 return 1;
178out_nomatch:
179 return 0;
180}
181
182int __init rpc_init_generic_auth(void)
183{
184 return rpcauth_init_credcache(&generic_auth);
185}
186
187void rpc_destroy_generic_auth(void)
188{
189 rpcauth_destroy_credcache(&generic_auth);
190}
191
192/*
193 * Test the the current time (now) against the underlying credential key expiry
194 * minus a timeout and setup notification.
195 *
196 * The normal case:
197 * If 'now' is before the key expiry minus RPC_KEY_EXPIRE_TIMEO, set
198 * the RPC_CRED_NOTIFY_TIMEOUT flag to setup the underlying credential
199 * rpc_credops crmatch routine to notify this generic cred when it's key
200 * expiration is within RPC_KEY_EXPIRE_TIMEO, and return 0.
201 *
202 * The error case:
203 * If the underlying cred lookup fails, return -EACCES.
204 *
205 * The 'almost' error case:
206 * If 'now' is within key expiry minus RPC_KEY_EXPIRE_TIMEO, but not within
207 * key expiry minus RPC_KEY_EXPIRE_FAIL, set the RPC_CRED_EXPIRE_SOON bit
208 * on the acred ac_flags and return 0.
209 */
210static int
211generic_key_timeout(struct rpc_auth *auth, struct rpc_cred *cred)
212{
213 struct auth_cred *acred = &container_of(cred, struct generic_cred,
214 gc_base)->acred;
215 struct rpc_cred *tcred;
216 int ret = 0;
217
218
219 /* Fast track for non crkey_timeout (no key) underlying credentials */
220 if (test_bit(RPC_CRED_NO_CRKEY_TIMEOUT, &acred->ac_flags))
221 return 0;
222
223 /* Fast track for the normal case */
224 if (test_bit(RPC_CRED_NOTIFY_TIMEOUT, &acred->ac_flags))
225 return 0;
226
227 /* lookup_cred either returns a valid referenced rpc_cred, or PTR_ERR */
228 tcred = auth->au_ops->lookup_cred(auth, acred, 0);
229 if (IS_ERR(tcred))
230 return -EACCES;
231
232 if (!tcred->cr_ops->crkey_timeout) {
233 set_bit(RPC_CRED_NO_CRKEY_TIMEOUT, &acred->ac_flags);
234 ret = 0;
235 goto out_put;
236 }
237
238 /* Test for the almost error case */
239 ret = tcred->cr_ops->crkey_timeout(tcred);
240 if (ret != 0) {
241 set_bit(RPC_CRED_KEY_EXPIRE_SOON, &acred->ac_flags);
242 ret = 0;
243 } else {
244 /* In case underlying cred key has been reset */
245 if (test_and_clear_bit(RPC_CRED_KEY_EXPIRE_SOON,
246 &acred->ac_flags))
247 dprintk("RPC: UID %d Credential key reset\n",
248 from_kuid(&init_user_ns, tcred->cr_uid));
249 /* set up fasttrack for the normal case */
250 set_bit(RPC_CRED_NOTIFY_TIMEOUT, &acred->ac_flags);
251 }
252
253out_put:
254 put_rpccred(tcred);
255 return ret;
256}
257
258static const struct rpc_authops generic_auth_ops = {
259 .owner = THIS_MODULE,
260 .au_name = "Generic",
261 .lookup_cred = generic_lookup_cred,
262 .crcreate = generic_create_cred,
263 .key_timeout = generic_key_timeout,
264};
265
266static struct rpc_auth generic_auth = {
267 .au_ops = &generic_auth_ops,
268 .au_count = ATOMIC_INIT(0),
269};
270
271static bool generic_key_to_expire(struct rpc_cred *cred)
272{
273 struct auth_cred *acred = &container_of(cred, struct generic_cred,
274 gc_base)->acred;
275 bool ret;
276
277 get_rpccred(cred);
278 ret = test_bit(RPC_CRED_KEY_EXPIRE_SOON, &acred->ac_flags);
279 put_rpccred(cred);
280
281 return ret;
282}
283
284static const struct rpc_credops generic_credops = {
285 .cr_name = "Generic cred",
286 .crdestroy = generic_destroy_cred,
287 .crbind = generic_bind_cred,
288 .crmatch = generic_match,
289 .crkey_to_expire = generic_key_to_expire,
290};
1/*
2 * Generic RPC credential
3 *
4 * Copyright (C) 2008, Trond Myklebust <Trond.Myklebust@netapp.com>
5 */
6
7#include <linux/err.h>
8#include <linux/slab.h>
9#include <linux/types.h>
10#include <linux/module.h>
11#include <linux/sched.h>
12#include <linux/sunrpc/auth.h>
13#include <linux/sunrpc/clnt.h>
14#include <linux/sunrpc/debug.h>
15#include <linux/sunrpc/sched.h>
16
17#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
18# define RPCDBG_FACILITY RPCDBG_AUTH
19#endif
20
21#define RPC_MACHINE_CRED_USERID GLOBAL_ROOT_UID
22#define RPC_MACHINE_CRED_GROUPID GLOBAL_ROOT_GID
23
24struct generic_cred {
25 struct rpc_cred gc_base;
26 struct auth_cred acred;
27};
28
29static struct rpc_auth generic_auth;
30static const struct rpc_credops generic_credops;
31
32/*
33 * Public call interface
34 */
35struct rpc_cred *rpc_lookup_cred(void)
36{
37 return rpcauth_lookupcred(&generic_auth, 0);
38}
39EXPORT_SYMBOL_GPL(rpc_lookup_cred);
40
41struct rpc_cred *
42rpc_lookup_generic_cred(struct auth_cred *acred, int flags, gfp_t gfp)
43{
44 return rpcauth_lookup_credcache(&generic_auth, acred, flags, gfp);
45}
46EXPORT_SYMBOL_GPL(rpc_lookup_generic_cred);
47
48struct rpc_cred *rpc_lookup_cred_nonblock(void)
49{
50 return rpcauth_lookupcred(&generic_auth, RPCAUTH_LOOKUP_RCU);
51}
52EXPORT_SYMBOL_GPL(rpc_lookup_cred_nonblock);
53
54/*
55 * Public call interface for looking up machine creds.
56 */
57struct rpc_cred *rpc_lookup_machine_cred(const char *service_name)
58{
59 struct auth_cred acred = {
60 .uid = RPC_MACHINE_CRED_USERID,
61 .gid = RPC_MACHINE_CRED_GROUPID,
62 .principal = service_name,
63 .machine_cred = 1,
64 };
65
66 dprintk("RPC: looking up machine cred for service %s\n",
67 service_name);
68 return generic_auth.au_ops->lookup_cred(&generic_auth, &acred, 0);
69}
70EXPORT_SYMBOL_GPL(rpc_lookup_machine_cred);
71
72static struct rpc_cred *generic_bind_cred(struct rpc_task *task,
73 struct rpc_cred *cred, int lookupflags)
74{
75 struct rpc_auth *auth = task->tk_client->cl_auth;
76 struct auth_cred *acred = &container_of(cred, struct generic_cred, gc_base)->acred;
77
78 return auth->au_ops->lookup_cred(auth, acred, lookupflags);
79}
80
81static int
82generic_hash_cred(struct auth_cred *acred, unsigned int hashbits)
83{
84 return hash_64(from_kgid(&init_user_ns, acred->gid) |
85 ((u64)from_kuid(&init_user_ns, acred->uid) <<
86 (sizeof(gid_t) * 8)), hashbits);
87}
88
89/*
90 * Lookup generic creds for current process
91 */
92static struct rpc_cred *
93generic_lookup_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags)
94{
95 return rpcauth_lookup_credcache(&generic_auth, acred, flags, GFP_KERNEL);
96}
97
98static struct rpc_cred *
99generic_create_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags, gfp_t gfp)
100{
101 struct generic_cred *gcred;
102
103 gcred = kmalloc(sizeof(*gcred), gfp);
104 if (gcred == NULL)
105 return ERR_PTR(-ENOMEM);
106
107 rpcauth_init_cred(&gcred->gc_base, acred, &generic_auth, &generic_credops);
108 gcred->gc_base.cr_flags = 1UL << RPCAUTH_CRED_UPTODATE;
109
110 gcred->acred.uid = acred->uid;
111 gcred->acred.gid = acred->gid;
112 gcred->acred.group_info = acred->group_info;
113 gcred->acred.ac_flags = 0;
114 if (gcred->acred.group_info != NULL)
115 get_group_info(gcred->acred.group_info);
116 gcred->acred.machine_cred = acred->machine_cred;
117 gcred->acred.principal = acred->principal;
118
119 dprintk("RPC: allocated %s cred %p for uid %d gid %d\n",
120 gcred->acred.machine_cred ? "machine" : "generic",
121 gcred,
122 from_kuid(&init_user_ns, acred->uid),
123 from_kgid(&init_user_ns, acred->gid));
124 return &gcred->gc_base;
125}
126
127static void
128generic_free_cred(struct rpc_cred *cred)
129{
130 struct generic_cred *gcred = container_of(cred, struct generic_cred, gc_base);
131
132 dprintk("RPC: generic_free_cred %p\n", gcred);
133 if (gcred->acred.group_info != NULL)
134 put_group_info(gcred->acred.group_info);
135 kfree(gcred);
136}
137
138static void
139generic_free_cred_callback(struct rcu_head *head)
140{
141 struct rpc_cred *cred = container_of(head, struct rpc_cred, cr_rcu);
142 generic_free_cred(cred);
143}
144
145static void
146generic_destroy_cred(struct rpc_cred *cred)
147{
148 call_rcu(&cred->cr_rcu, generic_free_cred_callback);
149}
150
151static int
152machine_cred_match(struct auth_cred *acred, struct generic_cred *gcred, int flags)
153{
154 if (!gcred->acred.machine_cred ||
155 gcred->acred.principal != acred->principal ||
156 !uid_eq(gcred->acred.uid, acred->uid) ||
157 !gid_eq(gcred->acred.gid, acred->gid))
158 return 0;
159 return 1;
160}
161
162/*
163 * Match credentials against current process creds.
164 */
165static int
166generic_match(struct auth_cred *acred, struct rpc_cred *cred, int flags)
167{
168 struct generic_cred *gcred = container_of(cred, struct generic_cred, gc_base);
169 int i;
170
171 if (acred->machine_cred)
172 return machine_cred_match(acred, gcred, flags);
173
174 if (!uid_eq(gcred->acred.uid, acred->uid) ||
175 !gid_eq(gcred->acred.gid, acred->gid) ||
176 gcred->acred.machine_cred != 0)
177 goto out_nomatch;
178
179 /* Optimisation in the case where pointers are identical... */
180 if (gcred->acred.group_info == acred->group_info)
181 goto out_match;
182
183 /* Slow path... */
184 if (gcred->acred.group_info->ngroups != acred->group_info->ngroups)
185 goto out_nomatch;
186 for (i = 0; i < gcred->acred.group_info->ngroups; i++) {
187 if (!gid_eq(gcred->acred.group_info->gid[i],
188 acred->group_info->gid[i]))
189 goto out_nomatch;
190 }
191out_match:
192 return 1;
193out_nomatch:
194 return 0;
195}
196
197int __init rpc_init_generic_auth(void)
198{
199 return rpcauth_init_credcache(&generic_auth);
200}
201
202void rpc_destroy_generic_auth(void)
203{
204 rpcauth_destroy_credcache(&generic_auth);
205}
206
207/*
208 * Test the the current time (now) against the underlying credential key expiry
209 * minus a timeout and setup notification.
210 *
211 * The normal case:
212 * If 'now' is before the key expiry minus RPC_KEY_EXPIRE_TIMEO, set
213 * the RPC_CRED_NOTIFY_TIMEOUT flag to setup the underlying credential
214 * rpc_credops crmatch routine to notify this generic cred when it's key
215 * expiration is within RPC_KEY_EXPIRE_TIMEO, and return 0.
216 *
217 * The error case:
218 * If the underlying cred lookup fails, return -EACCES.
219 *
220 * The 'almost' error case:
221 * If 'now' is within key expiry minus RPC_KEY_EXPIRE_TIMEO, but not within
222 * key expiry minus RPC_KEY_EXPIRE_FAIL, set the RPC_CRED_EXPIRE_SOON bit
223 * on the acred ac_flags and return 0.
224 */
225static int
226generic_key_timeout(struct rpc_auth *auth, struct rpc_cred *cred)
227{
228 struct auth_cred *acred = &container_of(cred, struct generic_cred,
229 gc_base)->acred;
230 struct rpc_cred *tcred;
231 int ret = 0;
232
233
234 /* Fast track for non crkey_timeout (no key) underlying credentials */
235 if (auth->au_flags & RPCAUTH_AUTH_NO_CRKEY_TIMEOUT)
236 return 0;
237
238 /* Fast track for the normal case */
239 if (test_bit(RPC_CRED_NOTIFY_TIMEOUT, &acred->ac_flags))
240 return 0;
241
242 /* lookup_cred either returns a valid referenced rpc_cred, or PTR_ERR */
243 tcred = auth->au_ops->lookup_cred(auth, acred, 0);
244 if (IS_ERR(tcred))
245 return -EACCES;
246
247 /* Test for the almost error case */
248 ret = tcred->cr_ops->crkey_timeout(tcred);
249 if (ret != 0) {
250 set_bit(RPC_CRED_KEY_EXPIRE_SOON, &acred->ac_flags);
251 ret = 0;
252 } else {
253 /* In case underlying cred key has been reset */
254 if (test_and_clear_bit(RPC_CRED_KEY_EXPIRE_SOON,
255 &acred->ac_flags))
256 dprintk("RPC: UID %d Credential key reset\n",
257 from_kuid(&init_user_ns, tcred->cr_uid));
258 /* set up fasttrack for the normal case */
259 set_bit(RPC_CRED_NOTIFY_TIMEOUT, &acred->ac_flags);
260 }
261
262 put_rpccred(tcred);
263 return ret;
264}
265
266static const struct rpc_authops generic_auth_ops = {
267 .owner = THIS_MODULE,
268 .au_name = "Generic",
269 .hash_cred = generic_hash_cred,
270 .lookup_cred = generic_lookup_cred,
271 .crcreate = generic_create_cred,
272 .key_timeout = generic_key_timeout,
273};
274
275static struct rpc_auth generic_auth = {
276 .au_ops = &generic_auth_ops,
277 .au_count = ATOMIC_INIT(0),
278};
279
280static bool generic_key_to_expire(struct rpc_cred *cred)
281{
282 struct auth_cred *acred = &container_of(cred, struct generic_cred,
283 gc_base)->acred;
284 bool ret;
285
286 get_rpccred(cred);
287 ret = test_bit(RPC_CRED_KEY_EXPIRE_SOON, &acred->ac_flags);
288 put_rpccred(cred);
289
290 return ret;
291}
292
293static const struct rpc_credops generic_credops = {
294 .cr_name = "Generic cred",
295 .crdestroy = generic_destroy_cred,
296 .crbind = generic_bind_cred,
297 .crmatch = generic_match,
298 .crkey_to_expire = generic_key_to_expire,
299};