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