1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Copyright (C) 2018 Samsung Electronics Co., Ltd.
4 */
5
6 #include <linux/list.h>
7 #include <linux/slab.h>
8 #include <linux/rwsem.h>
9 #include <linux/xarray.h>
10
11 #include "ksmbd_ida.h"
12 #include "user_session.h"
13 #include "user_config.h"
14 #include "tree_connect.h"
15 #include "../transport_ipc.h"
16 #include "../connection.h"
17 #include "../vfs_cache.h"
18
19 static DEFINE_IDA(session_ida);
20
21 #define SESSION_HASH_BITS 3
22 static DEFINE_HASHTABLE(sessions_table, SESSION_HASH_BITS);
23 static DECLARE_RWSEM(sessions_table_lock);
24
25 struct ksmbd_session_rpc {
26 int id;
27 unsigned int method;
28 };
29
free_channel_list(struct ksmbd_session * sess)30 static void free_channel_list(struct ksmbd_session *sess)
31 {
32 struct channel *chann;
33 unsigned long index;
34
35 xa_for_each(&sess->ksmbd_chann_list, index, chann) {
36 xa_erase(&sess->ksmbd_chann_list, index);
37 kfree(chann);
38 }
39
40 xa_destroy(&sess->ksmbd_chann_list);
41 }
42
__session_rpc_close(struct ksmbd_session * sess,struct ksmbd_session_rpc * entry)43 static void __session_rpc_close(struct ksmbd_session *sess,
44 struct ksmbd_session_rpc *entry)
45 {
46 struct ksmbd_rpc_command *resp;
47
48 resp = ksmbd_rpc_close(sess, entry->id);
49 if (!resp)
50 pr_err("Unable to close RPC pipe %d\n", entry->id);
51
52 kvfree(resp);
53 ksmbd_rpc_id_free(entry->id);
54 kfree(entry);
55 }
56
ksmbd_session_rpc_clear_list(struct ksmbd_session * sess)57 static void ksmbd_session_rpc_clear_list(struct ksmbd_session *sess)
58 {
59 struct ksmbd_session_rpc *entry;
60 long index;
61
62 xa_for_each(&sess->rpc_handle_list, index, entry) {
63 xa_erase(&sess->rpc_handle_list, index);
64 __session_rpc_close(sess, entry);
65 }
66
67 xa_destroy(&sess->rpc_handle_list);
68 }
69
__rpc_method(char * rpc_name)70 static int __rpc_method(char *rpc_name)
71 {
72 if (!strcmp(rpc_name, "\\srvsvc") || !strcmp(rpc_name, "srvsvc"))
73 return KSMBD_RPC_SRVSVC_METHOD_INVOKE;
74
75 if (!strcmp(rpc_name, "\\wkssvc") || !strcmp(rpc_name, "wkssvc"))
76 return KSMBD_RPC_WKSSVC_METHOD_INVOKE;
77
78 if (!strcmp(rpc_name, "LANMAN") || !strcmp(rpc_name, "lanman"))
79 return KSMBD_RPC_RAP_METHOD;
80
81 if (!strcmp(rpc_name, "\\samr") || !strcmp(rpc_name, "samr"))
82 return KSMBD_RPC_SAMR_METHOD_INVOKE;
83
84 if (!strcmp(rpc_name, "\\lsarpc") || !strcmp(rpc_name, "lsarpc"))
85 return KSMBD_RPC_LSARPC_METHOD_INVOKE;
86
87 pr_err("Unsupported RPC: %s\n", rpc_name);
88 return 0;
89 }
90
ksmbd_session_rpc_open(struct ksmbd_session * sess,char * rpc_name)91 int ksmbd_session_rpc_open(struct ksmbd_session *sess, char *rpc_name)
92 {
93 struct ksmbd_session_rpc *entry, *old;
94 struct ksmbd_rpc_command *resp;
95 int method;
96
97 method = __rpc_method(rpc_name);
98 if (!method)
99 return -EINVAL;
100
101 entry = kzalloc(sizeof(struct ksmbd_session_rpc), KSMBD_DEFAULT_GFP);
102 if (!entry)
103 return -ENOMEM;
104
105 entry->method = method;
106 entry->id = ksmbd_ipc_id_alloc();
107 if (entry->id < 0)
108 goto free_entry;
109 old = xa_store(&sess->rpc_handle_list, entry->id, entry, KSMBD_DEFAULT_GFP);
110 if (xa_is_err(old))
111 goto free_id;
112
113 resp = ksmbd_rpc_open(sess, entry->id);
114 if (!resp)
115 goto erase_xa;
116
117 kvfree(resp);
118 return entry->id;
119 erase_xa:
120 xa_erase(&sess->rpc_handle_list, entry->id);
121 free_id:
122 ksmbd_rpc_id_free(entry->id);
123 free_entry:
124 kfree(entry);
125 return -EINVAL;
126 }
127
ksmbd_session_rpc_close(struct ksmbd_session * sess,int id)128 void ksmbd_session_rpc_close(struct ksmbd_session *sess, int id)
129 {
130 struct ksmbd_session_rpc *entry;
131
132 entry = xa_erase(&sess->rpc_handle_list, id);
133 if (entry)
134 __session_rpc_close(sess, entry);
135 }
136
ksmbd_session_rpc_method(struct ksmbd_session * sess,int id)137 int ksmbd_session_rpc_method(struct ksmbd_session *sess, int id)
138 {
139 struct ksmbd_session_rpc *entry;
140
141 entry = xa_load(&sess->rpc_handle_list, id);
142 return entry ? entry->method : 0;
143 }
144
ksmbd_session_destroy(struct ksmbd_session * sess)145 void ksmbd_session_destroy(struct ksmbd_session *sess)
146 {
147 if (!sess)
148 return;
149
150 if (sess->user)
151 ksmbd_free_user(sess->user);
152
153 ksmbd_tree_conn_session_logoff(sess);
154 ksmbd_destroy_file_table(&sess->file_table);
155 ksmbd_launch_ksmbd_durable_scavenger();
156 ksmbd_session_rpc_clear_list(sess);
157 free_channel_list(sess);
158 kfree(sess->Preauth_HashValue);
159 ksmbd_release_id(&session_ida, sess->id);
160 kfree(sess);
161 }
162
__session_lookup(unsigned long long id)163 struct ksmbd_session *__session_lookup(unsigned long long id)
164 {
165 struct ksmbd_session *sess;
166
167 hash_for_each_possible(sessions_table, sess, hlist, id) {
168 if (id == sess->id) {
169 sess->last_active = jiffies;
170 return sess;
171 }
172 }
173 return NULL;
174 }
175
ksmbd_expire_session(struct ksmbd_conn * conn)176 static void ksmbd_expire_session(struct ksmbd_conn *conn)
177 {
178 unsigned long id;
179 struct ksmbd_session *sess;
180
181 down_write(&sessions_table_lock);
182 down_write(&conn->session_lock);
183 xa_for_each(&conn->sessions, id, sess) {
184 if (atomic_read(&sess->refcnt) <= 1 &&
185 (sess->state != SMB2_SESSION_VALID ||
186 time_after(jiffies,
187 sess->last_active + SMB2_SESSION_TIMEOUT))) {
188 xa_erase(&conn->sessions, sess->id);
189 hash_del(&sess->hlist);
190 ksmbd_session_destroy(sess);
191 continue;
192 }
193 }
194 up_write(&conn->session_lock);
195 up_write(&sessions_table_lock);
196 }
197
ksmbd_session_register(struct ksmbd_conn * conn,struct ksmbd_session * sess)198 int ksmbd_session_register(struct ksmbd_conn *conn,
199 struct ksmbd_session *sess)
200 {
201 sess->dialect = conn->dialect;
202 memcpy(sess->ClientGUID, conn->ClientGUID, SMB2_CLIENT_GUID_SIZE);
203 ksmbd_expire_session(conn);
204 return xa_err(xa_store(&conn->sessions, sess->id, sess, KSMBD_DEFAULT_GFP));
205 }
206
ksmbd_chann_del(struct ksmbd_conn * conn,struct ksmbd_session * sess)207 static int ksmbd_chann_del(struct ksmbd_conn *conn, struct ksmbd_session *sess)
208 {
209 struct channel *chann;
210
211 chann = xa_erase(&sess->ksmbd_chann_list, (long)conn);
212 if (!chann)
213 return -ENOENT;
214
215 kfree(chann);
216 return 0;
217 }
218
ksmbd_sessions_deregister(struct ksmbd_conn * conn)219 void ksmbd_sessions_deregister(struct ksmbd_conn *conn)
220 {
221 struct ksmbd_session *sess;
222 unsigned long id;
223
224 down_write(&sessions_table_lock);
225 if (conn->binding) {
226 int bkt;
227 struct hlist_node *tmp;
228
229 hash_for_each_safe(sessions_table, bkt, tmp, sess, hlist) {
230 if (!ksmbd_chann_del(conn, sess) &&
231 xa_empty(&sess->ksmbd_chann_list)) {
232 hash_del(&sess->hlist);
233 down_write(&conn->session_lock);
234 xa_erase(&conn->sessions, sess->id);
235 up_write(&conn->session_lock);
236 if (atomic_dec_and_test(&sess->refcnt))
237 ksmbd_session_destroy(sess);
238 }
239 }
240 }
241
242 down_write(&conn->session_lock);
243 xa_for_each(&conn->sessions, id, sess) {
244 unsigned long chann_id;
245 struct channel *chann;
246
247 xa_for_each(&sess->ksmbd_chann_list, chann_id, chann) {
248 if (chann->conn != conn)
249 ksmbd_conn_set_exiting(chann->conn);
250 }
251
252 ksmbd_chann_del(conn, sess);
253 if (xa_empty(&sess->ksmbd_chann_list)) {
254 xa_erase(&conn->sessions, sess->id);
255 hash_del(&sess->hlist);
256 if (atomic_dec_and_test(&sess->refcnt))
257 ksmbd_session_destroy(sess);
258 }
259 }
260 up_write(&conn->session_lock);
261 up_write(&sessions_table_lock);
262 }
263
is_ksmbd_session_in_connection(struct ksmbd_conn * conn,unsigned long long id)264 bool is_ksmbd_session_in_connection(struct ksmbd_conn *conn,
265 unsigned long long id)
266 {
267 struct ksmbd_session *sess;
268
269 down_read(&conn->session_lock);
270 sess = xa_load(&conn->sessions, id);
271 if (sess) {
272 up_read(&conn->session_lock);
273 return true;
274 }
275 up_read(&conn->session_lock);
276
277 return false;
278 }
279
ksmbd_session_lookup(struct ksmbd_conn * conn,unsigned long long id)280 struct ksmbd_session *ksmbd_session_lookup(struct ksmbd_conn *conn,
281 unsigned long long id)
282 {
283 struct ksmbd_session *sess;
284
285 down_read(&conn->session_lock);
286 sess = xa_load(&conn->sessions, id);
287 if (sess) {
288 sess->last_active = jiffies;
289 ksmbd_user_session_get(sess);
290 }
291 up_read(&conn->session_lock);
292 return sess;
293 }
294
ksmbd_session_lookup_slowpath(unsigned long long id)295 struct ksmbd_session *ksmbd_session_lookup_slowpath(unsigned long long id)
296 {
297 struct ksmbd_session *sess;
298
299 down_read(&sessions_table_lock);
300 sess = __session_lookup(id);
301 if (sess)
302 ksmbd_user_session_get(sess);
303 up_read(&sessions_table_lock);
304
305 return sess;
306 }
307
ksmbd_session_lookup_all(struct ksmbd_conn * conn,unsigned long long id)308 struct ksmbd_session *ksmbd_session_lookup_all(struct ksmbd_conn *conn,
309 unsigned long long id)
310 {
311 struct ksmbd_session *sess;
312
313 sess = ksmbd_session_lookup(conn, id);
314 if (!sess && conn->binding)
315 sess = ksmbd_session_lookup_slowpath(id);
316 if (sess && sess->state != SMB2_SESSION_VALID)
317 sess = NULL;
318 return sess;
319 }
320
ksmbd_user_session_get(struct ksmbd_session * sess)321 void ksmbd_user_session_get(struct ksmbd_session *sess)
322 {
323 atomic_inc(&sess->refcnt);
324 }
325
ksmbd_user_session_put(struct ksmbd_session * sess)326 void ksmbd_user_session_put(struct ksmbd_session *sess)
327 {
328 if (!sess)
329 return;
330
331 if (atomic_read(&sess->refcnt) <= 0)
332 WARN_ON(1);
333 else if (atomic_dec_and_test(&sess->refcnt))
334 ksmbd_session_destroy(sess);
335 }
336
ksmbd_preauth_session_alloc(struct ksmbd_conn * conn,u64 sess_id)337 struct preauth_session *ksmbd_preauth_session_alloc(struct ksmbd_conn *conn,
338 u64 sess_id)
339 {
340 struct preauth_session *sess;
341
342 sess = kmalloc(sizeof(struct preauth_session), KSMBD_DEFAULT_GFP);
343 if (!sess)
344 return NULL;
345
346 sess->id = sess_id;
347 memcpy(sess->Preauth_HashValue, conn->preauth_info->Preauth_HashValue,
348 PREAUTH_HASHVALUE_SIZE);
349 list_add(&sess->preauth_entry, &conn->preauth_sess_table);
350
351 return sess;
352 }
353
destroy_previous_session(struct ksmbd_conn * conn,struct ksmbd_user * user,u64 id)354 void destroy_previous_session(struct ksmbd_conn *conn,
355 struct ksmbd_user *user, u64 id)
356 {
357 struct ksmbd_session *prev_sess;
358 struct ksmbd_user *prev_user;
359 int err;
360
361 down_write(&sessions_table_lock);
362 down_write(&conn->session_lock);
363 prev_sess = __session_lookup(id);
364 if (!prev_sess || prev_sess->state == SMB2_SESSION_EXPIRED)
365 goto out;
366
367 prev_user = prev_sess->user;
368 if (!prev_user ||
369 strcmp(user->name, prev_user->name) ||
370 user->passkey_sz != prev_user->passkey_sz ||
371 memcmp(user->passkey, prev_user->passkey, user->passkey_sz))
372 goto out;
373
374 ksmbd_all_conn_set_status(id, KSMBD_SESS_NEED_RECONNECT);
375 err = ksmbd_conn_wait_idle_sess_id(conn, id);
376 if (err) {
377 ksmbd_all_conn_set_status(id, KSMBD_SESS_NEED_SETUP);
378 goto out;
379 }
380
381 ksmbd_destroy_file_table(&prev_sess->file_table);
382 prev_sess->state = SMB2_SESSION_EXPIRED;
383 ksmbd_all_conn_set_status(id, KSMBD_SESS_NEED_SETUP);
384 ksmbd_launch_ksmbd_durable_scavenger();
385 out:
386 up_write(&conn->session_lock);
387 up_write(&sessions_table_lock);
388 }
389
ksmbd_preauth_session_id_match(struct preauth_session * sess,unsigned long long id)390 static bool ksmbd_preauth_session_id_match(struct preauth_session *sess,
391 unsigned long long id)
392 {
393 return sess->id == id;
394 }
395
ksmbd_preauth_session_lookup(struct ksmbd_conn * conn,unsigned long long id)396 struct preauth_session *ksmbd_preauth_session_lookup(struct ksmbd_conn *conn,
397 unsigned long long id)
398 {
399 struct preauth_session *sess = NULL;
400
401 list_for_each_entry(sess, &conn->preauth_sess_table, preauth_entry) {
402 if (ksmbd_preauth_session_id_match(sess, id))
403 return sess;
404 }
405 return NULL;
406 }
407
__init_smb2_session(struct ksmbd_session * sess)408 static int __init_smb2_session(struct ksmbd_session *sess)
409 {
410 int id = ksmbd_acquire_smb2_uid(&session_ida);
411
412 if (id < 0)
413 return -EINVAL;
414 sess->id = id;
415 return 0;
416 }
417
__session_create(int protocol)418 static struct ksmbd_session *__session_create(int protocol)
419 {
420 struct ksmbd_session *sess;
421 int ret;
422
423 if (protocol != CIFDS_SESSION_FLAG_SMB2)
424 return NULL;
425
426 sess = kzalloc(sizeof(struct ksmbd_session), KSMBD_DEFAULT_GFP);
427 if (!sess)
428 return NULL;
429
430 if (ksmbd_init_file_table(&sess->file_table))
431 goto error;
432
433 sess->last_active = jiffies;
434 sess->state = SMB2_SESSION_IN_PROGRESS;
435 set_session_flag(sess, protocol);
436 xa_init(&sess->tree_conns);
437 xa_init(&sess->ksmbd_chann_list);
438 xa_init(&sess->rpc_handle_list);
439 sess->sequence_number = 1;
440 rwlock_init(&sess->tree_conns_lock);
441 atomic_set(&sess->refcnt, 2);
442
443 ret = __init_smb2_session(sess);
444 if (ret)
445 goto error;
446
447 ida_init(&sess->tree_conn_ida);
448
449 down_write(&sessions_table_lock);
450 hash_add(sessions_table, &sess->hlist, sess->id);
451 up_write(&sessions_table_lock);
452
453 return sess;
454
455 error:
456 ksmbd_session_destroy(sess);
457 return NULL;
458 }
459
ksmbd_smb2_session_create(void)460 struct ksmbd_session *ksmbd_smb2_session_create(void)
461 {
462 return __session_create(CIFDS_SESSION_FLAG_SMB2);
463 }
464
ksmbd_acquire_tree_conn_id(struct ksmbd_session * sess)465 int ksmbd_acquire_tree_conn_id(struct ksmbd_session *sess)
466 {
467 int id = -EINVAL;
468
469 if (test_session_flag(sess, CIFDS_SESSION_FLAG_SMB2))
470 id = ksmbd_acquire_smb2_tid(&sess->tree_conn_ida);
471
472 return id;
473 }
474
ksmbd_release_tree_conn_id(struct ksmbd_session * sess,int id)475 void ksmbd_release_tree_conn_id(struct ksmbd_session *sess, int id)
476 {
477 if (id >= 0)
478 ksmbd_release_id(&sess->tree_conn_ida, id);
479 }
480