1 | /* SPDX-License-Identifier: GPL-2.0 */ |
2 | /* |
3 | * linux/include/linux/lockd/lockd.h |
4 | * |
5 | * General-purpose lockd include file. |
6 | * |
7 | * Copyright (C) 1996 Olaf Kirch <okir@monad.swb.de> |
8 | */ |
9 | |
10 | #ifndef LINUX_LOCKD_LOCKD_H |
11 | #define LINUX_LOCKD_LOCKD_H |
12 | |
13 | /* XXX: a lot of this should really be under fs/lockd. */ |
14 | |
15 | #include <linux/in.h> |
16 | #include <linux/in6.h> |
17 | #include <net/ipv6.h> |
18 | #include <linux/fs.h> |
19 | #include <linux/kref.h> |
20 | #include <linux/refcount.h> |
21 | #include <linux/utsname.h> |
22 | #include <linux/lockd/bind.h> |
23 | #include <linux/lockd/xdr.h> |
24 | #ifdef CONFIG_LOCKD_V4 |
25 | #include <linux/lockd/xdr4.h> |
26 | #endif |
27 | #include <linux/lockd/debug.h> |
28 | #include <linux/sunrpc/svc.h> |
29 | |
30 | /* |
31 | * Version string |
32 | */ |
33 | #define LOCKD_VERSION "0.5" |
34 | |
35 | /* |
36 | * Default timeout for RPC calls (seconds) |
37 | */ |
38 | #define LOCKD_DFLT_TIMEO 10 |
39 | |
40 | /* |
41 | * Lockd host handle (used both by the client and server personality). |
42 | */ |
43 | struct nlm_host { |
44 | struct hlist_node h_hash; /* doubly linked list */ |
45 | struct sockaddr_storage h_addr; /* peer address */ |
46 | size_t h_addrlen; |
47 | struct sockaddr_storage h_srcaddr; /* our address (optional) */ |
48 | size_t h_srcaddrlen; |
49 | struct rpc_clnt *h_rpcclnt; /* RPC client to talk to peer */ |
50 | char *h_name; /* remote hostname */ |
51 | u32 h_version; /* interface version */ |
52 | unsigned short h_proto; /* transport proto */ |
53 | unsigned short h_reclaiming : 1, |
54 | h_server : 1, /* server side, not client side */ |
55 | h_noresvport : 1, |
56 | h_inuse : 1; |
57 | wait_queue_head_t h_gracewait; /* wait while reclaiming */ |
58 | struct rw_semaphore h_rwsem; /* Reboot recovery lock */ |
59 | u32 h_state; /* pseudo-state counter */ |
60 | u32 h_nsmstate; /* true remote NSM state */ |
61 | u32 h_pidcount; /* Pseudopids */ |
62 | refcount_t h_count; /* reference count */ |
63 | struct mutex h_mutex; /* mutex for pmap binding */ |
64 | unsigned long h_nextrebind; /* next portmap call */ |
65 | unsigned long h_expires; /* eligible for GC */ |
66 | struct list_head h_lockowners; /* Lockowners for the client */ |
67 | spinlock_t h_lock; |
68 | struct list_head h_granted; /* Locks in GRANTED state */ |
69 | struct list_head h_reclaim; /* Locks in RECLAIM state */ |
70 | struct nsm_handle *h_nsmhandle; /* NSM status handle */ |
71 | char *h_addrbuf; /* address eyecatcher */ |
72 | struct net *net; /* host net */ |
73 | const struct cred *h_cred; |
74 | char nodename[UNX_MAXNODENAME + 1]; |
75 | const struct nlmclnt_operations *h_nlmclnt_ops; /* Callback ops for NLM users */ |
76 | }; |
77 | |
78 | /* |
79 | * The largest string sm_addrbuf should hold is a full-size IPv6 address |
80 | * (no "::" anywhere) with a scope ID. The buffer size is computed to |
81 | * hold eight groups of colon-separated four-hex-digit numbers, a |
82 | * percent sign, a scope id (at most 32 bits, in decimal), and NUL. |
83 | */ |
84 | #define NSM_ADDRBUF ((8 * 4 + 7) + (1 + 10) + 1) |
85 | |
86 | struct nsm_handle { |
87 | struct list_head sm_link; |
88 | refcount_t sm_count; |
89 | char *sm_mon_name; |
90 | char *sm_name; |
91 | struct sockaddr_storage sm_addr; |
92 | size_t sm_addrlen; |
93 | unsigned int sm_monitored : 1, |
94 | sm_sticky : 1; /* don't unmonitor */ |
95 | struct nsm_private sm_priv; |
96 | char sm_addrbuf[NSM_ADDRBUF]; |
97 | }; |
98 | |
99 | /* |
100 | * Rigorous type checking on sockaddr type conversions |
101 | */ |
102 | static inline struct sockaddr *nlm_addr(const struct nlm_host *host) |
103 | { |
104 | return (struct sockaddr *)&host->h_addr; |
105 | } |
106 | |
107 | static inline struct sockaddr *nlm_srcaddr(const struct nlm_host *host) |
108 | { |
109 | return (struct sockaddr *)&host->h_srcaddr; |
110 | } |
111 | |
112 | /* |
113 | * Map an fl_owner_t into a unique 32-bit "pid" |
114 | */ |
115 | struct nlm_lockowner { |
116 | struct list_head list; |
117 | refcount_t count; |
118 | |
119 | struct nlm_host *host; |
120 | fl_owner_t owner; |
121 | uint32_t pid; |
122 | }; |
123 | |
124 | /* |
125 | * This is the representation of a blocked client lock. |
126 | */ |
127 | struct nlm_wait { |
128 | struct list_head b_list; /* linked list */ |
129 | wait_queue_head_t b_wait; /* where to wait on */ |
130 | struct nlm_host *b_host; |
131 | struct file_lock *b_lock; /* local file lock */ |
132 | __be32 b_status; /* grant callback status */ |
133 | }; |
134 | |
135 | /* |
136 | * Memory chunk for NLM client RPC request. |
137 | */ |
138 | #define NLMCLNT_OHSIZE ((__NEW_UTS_LEN) + 10u) |
139 | struct nlm_rqst { |
140 | refcount_t a_count; |
141 | unsigned int a_flags; /* initial RPC task flags */ |
142 | struct nlm_host * a_host; /* host handle */ |
143 | struct nlm_args a_args; /* arguments */ |
144 | struct nlm_res a_res; /* result */ |
145 | struct nlm_block * a_block; |
146 | unsigned int a_retries; /* Retry count */ |
147 | u8 a_owner[NLMCLNT_OHSIZE]; |
148 | void * a_callback_data; /* sent to nlmclnt_operations callbacks */ |
149 | }; |
150 | |
151 | /* |
152 | * This struct describes a file held open by lockd on behalf of |
153 | * an NFS client. |
154 | */ |
155 | struct nlm_file { |
156 | struct hlist_node f_list; /* linked list */ |
157 | struct nfs_fh f_handle; /* NFS file handle */ |
158 | struct file * f_file[2]; /* VFS file pointers, |
159 | indexed by O_ flags */ |
160 | struct nlm_share * f_shares; /* DOS shares */ |
161 | struct list_head f_blocks; /* blocked locks */ |
162 | unsigned int f_locks; /* guesstimate # of locks */ |
163 | unsigned int f_count; /* reference count */ |
164 | struct mutex f_mutex; /* avoid concurrent access */ |
165 | }; |
166 | |
167 | /* |
168 | * This is a server block (i.e. a lock requested by some client which |
169 | * couldn't be granted because of a conflicting lock). |
170 | */ |
171 | #define NLM_NEVER (~(unsigned long) 0) |
172 | /* timeout on non-blocking call: */ |
173 | #define NLM_TIMEOUT (7 * HZ) |
174 | |
175 | struct nlm_block { |
176 | struct kref b_count; /* Reference count */ |
177 | struct list_head b_list; /* linked list of all blocks */ |
178 | struct list_head b_flist; /* linked list (per file) */ |
179 | struct nlm_rqst * b_call; /* RPC args & callback info */ |
180 | struct svc_serv * b_daemon; /* NLM service */ |
181 | struct nlm_host * b_host; /* host handle for RPC clnt */ |
182 | unsigned long b_when; /* next re-xmit */ |
183 | unsigned int b_id; /* block id */ |
184 | unsigned char b_granted; /* VFS granted lock */ |
185 | struct nlm_file * b_file; /* file in question */ |
186 | struct cache_req * b_cache_req; /* deferred request handling */ |
187 | struct cache_deferred_req * b_deferred_req; |
188 | unsigned int b_flags; /* block flags */ |
189 | #define B_QUEUED 1 /* lock queued */ |
190 | #define B_GOT_CALLBACK 2 /* got lock or conflicting lock */ |
191 | #define B_TIMED_OUT 4 /* filesystem too slow to respond */ |
192 | }; |
193 | |
194 | /* |
195 | * Global variables |
196 | */ |
197 | extern const struct rpc_program nlm_program; |
198 | extern const struct svc_procedure nlmsvc_procedures[24]; |
199 | #ifdef CONFIG_LOCKD_V4 |
200 | extern const struct svc_procedure nlmsvc_procedures4[24]; |
201 | #endif |
202 | extern int nlmsvc_grace_period; |
203 | extern unsigned long nlmsvc_timeout; |
204 | extern bool nsm_use_hostnames; |
205 | extern u32 nsm_local_state; |
206 | |
207 | extern struct timer_list nlmsvc_retry; |
208 | |
209 | /* |
210 | * Lockd client functions |
211 | */ |
212 | struct nlm_rqst * nlm_alloc_call(struct nlm_host *host); |
213 | int nlm_async_call(struct nlm_rqst *, u32, const struct rpc_call_ops *); |
214 | int nlm_async_reply(struct nlm_rqst *, u32, const struct rpc_call_ops *); |
215 | void nlmclnt_release_call(struct nlm_rqst *); |
216 | void nlmclnt_prepare_block(struct nlm_wait *block, struct nlm_host *host, |
217 | struct file_lock *fl); |
218 | void nlmclnt_queue_block(struct nlm_wait *block); |
219 | __be32 nlmclnt_dequeue_block(struct nlm_wait *block); |
220 | int nlmclnt_wait(struct nlm_wait *block, struct nlm_rqst *req, long timeout); |
221 | __be32 nlmclnt_grant(const struct sockaddr *addr, |
222 | const struct nlm_lock *lock); |
223 | void nlmclnt_recovery(struct nlm_host *); |
224 | int nlmclnt_reclaim(struct nlm_host *, struct file_lock *, |
225 | struct nlm_rqst *); |
226 | void nlmclnt_next_cookie(struct nlm_cookie *); |
227 | |
228 | /* |
229 | * Host cache |
230 | */ |
231 | struct nlm_host *nlmclnt_lookup_host(const struct sockaddr *sap, |
232 | const size_t salen, |
233 | const unsigned short protocol, |
234 | const u32 version, |
235 | const char *hostname, |
236 | int noresvport, |
237 | struct net *net, |
238 | const struct cred *cred); |
239 | void nlmclnt_release_host(struct nlm_host *); |
240 | struct nlm_host *nlmsvc_lookup_host(const struct svc_rqst *rqstp, |
241 | const char *hostname, |
242 | const size_t hostname_len); |
243 | void nlmsvc_release_host(struct nlm_host *); |
244 | struct rpc_clnt * nlm_bind_host(struct nlm_host *); |
245 | void nlm_rebind_host(struct nlm_host *); |
246 | struct nlm_host * nlm_get_host(struct nlm_host *); |
247 | void nlm_shutdown_hosts(void); |
248 | void nlm_shutdown_hosts_net(struct net *net); |
249 | void nlm_host_rebooted(const struct net *net, |
250 | const struct nlm_reboot *); |
251 | |
252 | /* |
253 | * Host monitoring |
254 | */ |
255 | int nsm_monitor(const struct nlm_host *host); |
256 | void nsm_unmonitor(const struct nlm_host *host); |
257 | |
258 | struct nsm_handle *nsm_get_handle(const struct net *net, |
259 | const struct sockaddr *sap, |
260 | const size_t salen, |
261 | const char *hostname, |
262 | const size_t hostname_len); |
263 | struct nsm_handle *nsm_reboot_lookup(const struct net *net, |
264 | const struct nlm_reboot *info); |
265 | void nsm_release(struct nsm_handle *nsm); |
266 | |
267 | /* |
268 | * This is used in garbage collection and resource reclaim |
269 | * A return value != 0 means destroy the lock/block/share |
270 | */ |
271 | typedef int (*nlm_host_match_fn_t)(void *cur, struct nlm_host *ref); |
272 | |
273 | /* |
274 | * Server-side lock handling |
275 | */ |
276 | int lock_to_openmode(struct file_lock *); |
277 | __be32 nlmsvc_lock(struct svc_rqst *, struct nlm_file *, |
278 | struct nlm_host *, struct nlm_lock *, int, |
279 | struct nlm_cookie *, int); |
280 | __be32 nlmsvc_unlock(struct net *net, struct nlm_file *, struct nlm_lock *); |
281 | __be32 nlmsvc_testlock(struct svc_rqst *, struct nlm_file *, |
282 | struct nlm_host *, struct nlm_lock *, |
283 | struct nlm_lock *, struct nlm_cookie *); |
284 | __be32 nlmsvc_cancel_blocked(struct net *net, struct nlm_file *, struct nlm_lock *); |
285 | void nlmsvc_retry_blocked(struct svc_rqst *rqstp); |
286 | void nlmsvc_traverse_blocks(struct nlm_host *, struct nlm_file *, |
287 | nlm_host_match_fn_t match); |
288 | void nlmsvc_grant_reply(struct nlm_cookie *, __be32); |
289 | void nlmsvc_release_call(struct nlm_rqst *); |
290 | void nlmsvc_locks_init_private(struct file_lock *, struct nlm_host *, pid_t); |
291 | |
292 | /* |
293 | * File handling for the server personality |
294 | */ |
295 | __be32 nlm_lookup_file(struct svc_rqst *, struct nlm_file **, |
296 | struct nlm_lock *); |
297 | void nlm_release_file(struct nlm_file *); |
298 | void nlmsvc_put_lockowner(struct nlm_lockowner *); |
299 | void nlmsvc_release_lockowner(struct nlm_lock *); |
300 | void nlmsvc_mark_resources(struct net *); |
301 | void nlmsvc_free_host_resources(struct nlm_host *); |
302 | void nlmsvc_invalidate_all(void); |
303 | |
304 | /* |
305 | * Cluster failover support |
306 | */ |
307 | int nlmsvc_unlock_all_by_sb(struct super_block *sb); |
308 | int nlmsvc_unlock_all_by_ip(struct sockaddr *server_addr); |
309 | |
310 | static inline struct file *nlmsvc_file_file(struct nlm_file *file) |
311 | { |
312 | return file->f_file[O_RDONLY] ? |
313 | file->f_file[O_RDONLY] : file->f_file[O_WRONLY]; |
314 | } |
315 | |
316 | static inline struct inode *nlmsvc_file_inode(struct nlm_file *file) |
317 | { |
318 | return file_inode(f: nlmsvc_file_file(file)); |
319 | } |
320 | |
321 | static inline int __nlm_privileged_request4(const struct sockaddr *sap) |
322 | { |
323 | const struct sockaddr_in *sin = (struct sockaddr_in *)sap; |
324 | |
325 | if (ntohs(sin->sin_port) > 1023) |
326 | return 0; |
327 | |
328 | return ipv4_is_loopback(addr: sin->sin_addr.s_addr); |
329 | } |
330 | |
331 | #if IS_ENABLED(CONFIG_IPV6) |
332 | static inline int __nlm_privileged_request6(const struct sockaddr *sap) |
333 | { |
334 | const struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap; |
335 | |
336 | if (ntohs(sin6->sin6_port) > 1023) |
337 | return 0; |
338 | |
339 | if (ipv6_addr_type(addr: &sin6->sin6_addr) & IPV6_ADDR_MAPPED) |
340 | return ipv4_is_loopback(addr: sin6->sin6_addr.s6_addr32[3]); |
341 | |
342 | return ipv6_addr_type(addr: &sin6->sin6_addr) & IPV6_ADDR_LOOPBACK; |
343 | } |
344 | #else /* IS_ENABLED(CONFIG_IPV6) */ |
345 | static inline int __nlm_privileged_request6(const struct sockaddr *sap) |
346 | { |
347 | return 0; |
348 | } |
349 | #endif /* IS_ENABLED(CONFIG_IPV6) */ |
350 | |
351 | /* |
352 | * Ensure incoming requests are from local privileged callers. |
353 | * |
354 | * Return TRUE if sender is local and is connecting via a privileged port; |
355 | * otherwise return FALSE. |
356 | */ |
357 | static inline int nlm_privileged_requester(const struct svc_rqst *rqstp) |
358 | { |
359 | const struct sockaddr *sap = svc_addr(rqst: rqstp); |
360 | |
361 | switch (sap->sa_family) { |
362 | case AF_INET: |
363 | return __nlm_privileged_request4(sap); |
364 | case AF_INET6: |
365 | return __nlm_privileged_request6(sap); |
366 | default: |
367 | return 0; |
368 | } |
369 | } |
370 | |
371 | /* |
372 | * Compare two NLM locks. |
373 | * When the second lock is of type F_UNLCK, this acts like a wildcard. |
374 | */ |
375 | static inline int nlm_compare_locks(const struct file_lock *fl1, |
376 | const struct file_lock *fl2) |
377 | { |
378 | return file_inode(f: fl1->c.flc_file) == file_inode(f: fl2->c.flc_file) |
379 | && fl1->c.flc_pid == fl2->c.flc_pid |
380 | && fl1->c.flc_owner == fl2->c.flc_owner |
381 | && fl1->fl_start == fl2->fl_start |
382 | && fl1->fl_end == fl2->fl_end |
383 | &&(fl1->c.flc_type == fl2->c.flc_type || fl2->c.flc_type == F_UNLCK); |
384 | } |
385 | |
386 | extern const struct lock_manager_operations nlmsvc_lock_operations; |
387 | |
388 | #endif /* LINUX_LOCKD_LOCKD_H */ |
389 | |