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 <[email protected]> 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 /* 208 * Lockd client functions 209 */ 210 struct nlm_rqst * nlm_alloc_call(struct nlm_host *host); 211 int nlm_async_call(struct nlm_rqst *, u32, const struct rpc_call_ops *); 212 int nlm_async_reply(struct nlm_rqst *, u32, const struct rpc_call_ops *); 213 void nlmclnt_release_call(struct nlm_rqst *); 214 struct nlm_wait * nlmclnt_prepare_block(struct nlm_host *host, struct file_lock *fl); 215 void nlmclnt_finish_block(struct nlm_wait *block); 216 int nlmclnt_block(struct nlm_wait *block, struct nlm_rqst *req, long timeout); 217 __be32 nlmclnt_grant(const struct sockaddr *addr, 218 const struct nlm_lock *lock); 219 void nlmclnt_recovery(struct nlm_host *); 220 int nlmclnt_reclaim(struct nlm_host *, struct file_lock *, 221 struct nlm_rqst *); 222 void nlmclnt_next_cookie(struct nlm_cookie *); 223 224 /* 225 * Host cache 226 */ 227 struct nlm_host *nlmclnt_lookup_host(const struct sockaddr *sap, 228 const size_t salen, 229 const unsigned short protocol, 230 const u32 version, 231 const char *hostname, 232 int noresvport, 233 struct net *net, 234 const struct cred *cred); 235 void nlmclnt_release_host(struct nlm_host *); 236 struct nlm_host *nlmsvc_lookup_host(const struct svc_rqst *rqstp, 237 const char *hostname, 238 const size_t hostname_len); 239 void nlmsvc_release_host(struct nlm_host *); 240 struct rpc_clnt * nlm_bind_host(struct nlm_host *); 241 void nlm_rebind_host(struct nlm_host *); 242 struct nlm_host * nlm_get_host(struct nlm_host *); 243 void nlm_shutdown_hosts(void); 244 void nlm_shutdown_hosts_net(struct net *net); 245 void nlm_host_rebooted(const struct net *net, 246 const struct nlm_reboot *); 247 248 /* 249 * Host monitoring 250 */ 251 int nsm_monitor(const struct nlm_host *host); 252 void nsm_unmonitor(const struct nlm_host *host); 253 254 struct nsm_handle *nsm_get_handle(const struct net *net, 255 const struct sockaddr *sap, 256 const size_t salen, 257 const char *hostname, 258 const size_t hostname_len); 259 struct nsm_handle *nsm_reboot_lookup(const struct net *net, 260 const struct nlm_reboot *info); 261 void nsm_release(struct nsm_handle *nsm); 262 263 /* 264 * This is used in garbage collection and resource reclaim 265 * A return value != 0 means destroy the lock/block/share 266 */ 267 typedef int (*nlm_host_match_fn_t)(void *cur, struct nlm_host *ref); 268 269 /* 270 * Server-side lock handling 271 */ 272 int lock_to_openmode(struct file_lock *); 273 __be32 nlmsvc_lock(struct svc_rqst *, struct nlm_file *, 274 struct nlm_host *, struct nlm_lock *, int, 275 struct nlm_cookie *, int); 276 __be32 nlmsvc_unlock(struct net *net, struct nlm_file *, struct nlm_lock *); 277 __be32 nlmsvc_testlock(struct svc_rqst *, struct nlm_file *, 278 struct nlm_host *, struct nlm_lock *, 279 struct nlm_lock *, struct nlm_cookie *); 280 __be32 nlmsvc_cancel_blocked(struct net *net, struct nlm_file *, struct nlm_lock *); 281 unsigned long nlmsvc_retry_blocked(void); 282 void nlmsvc_traverse_blocks(struct nlm_host *, struct nlm_file *, 283 nlm_host_match_fn_t match); 284 void nlmsvc_grant_reply(struct nlm_cookie *, __be32); 285 void nlmsvc_release_call(struct nlm_rqst *); 286 void nlmsvc_locks_init_private(struct file_lock *, struct nlm_host *, pid_t); 287 288 /* 289 * File handling for the server personality 290 */ 291 __be32 nlm_lookup_file(struct svc_rqst *, struct nlm_file **, 292 struct nlm_lock *); 293 void nlm_release_file(struct nlm_file *); 294 void nlmsvc_put_lockowner(struct nlm_lockowner *); 295 void nlmsvc_release_lockowner(struct nlm_lock *); 296 void nlmsvc_mark_resources(struct net *); 297 void nlmsvc_free_host_resources(struct nlm_host *); 298 void nlmsvc_invalidate_all(void); 299 300 /* 301 * Cluster failover support 302 */ 303 int nlmsvc_unlock_all_by_sb(struct super_block *sb); 304 int nlmsvc_unlock_all_by_ip(struct sockaddr *server_addr); 305 306 static inline struct file *nlmsvc_file_file(struct nlm_file *file) 307 { 308 return file->f_file[O_RDONLY] ? 309 file->f_file[O_RDONLY] : file->f_file[O_WRONLY]; 310 } 311 312 static inline struct inode *nlmsvc_file_inode(struct nlm_file *file) 313 { 314 return file_inode(nlmsvc_file_file(file)); 315 } 316 317 static inline int __nlm_privileged_request4(const struct sockaddr *sap) 318 { 319 const struct sockaddr_in *sin = (struct sockaddr_in *)sap; 320 321 if (ntohs(sin->sin_port) > 1023) 322 return 0; 323 324 return ipv4_is_loopback(sin->sin_addr.s_addr); 325 } 326 327 #if IS_ENABLED(CONFIG_IPV6) 328 static inline int __nlm_privileged_request6(const struct sockaddr *sap) 329 { 330 const struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap; 331 332 if (ntohs(sin6->sin6_port) > 1023) 333 return 0; 334 335 if (ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_MAPPED) 336 return ipv4_is_loopback(sin6->sin6_addr.s6_addr32[3]); 337 338 return ipv6_addr_type(&sin6->sin6_addr) & IPV6_ADDR_LOOPBACK; 339 } 340 #else /* IS_ENABLED(CONFIG_IPV6) */ 341 static inline int __nlm_privileged_request6(const struct sockaddr *sap) 342 { 343 return 0; 344 } 345 #endif /* IS_ENABLED(CONFIG_IPV6) */ 346 347 /* 348 * Ensure incoming requests are from local privileged callers. 349 * 350 * Return TRUE if sender is local and is connecting via a privileged port; 351 * otherwise return FALSE. 352 */ 353 static inline int nlm_privileged_requester(const struct svc_rqst *rqstp) 354 { 355 const struct sockaddr *sap = svc_addr(rqstp); 356 357 switch (sap->sa_family) { 358 case AF_INET: 359 return __nlm_privileged_request4(sap); 360 case AF_INET6: 361 return __nlm_privileged_request6(sap); 362 default: 363 return 0; 364 } 365 } 366 367 /* 368 * Compare two NLM locks. 369 * When the second lock is of type F_UNLCK, this acts like a wildcard. 370 */ 371 static inline int nlm_compare_locks(const struct file_lock *fl1, 372 const struct file_lock *fl2) 373 { 374 return file_inode(fl1->fl_file) == file_inode(fl2->fl_file) 375 && fl1->fl_pid == fl2->fl_pid 376 && fl1->fl_owner == fl2->fl_owner 377 && fl1->fl_start == fl2->fl_start 378 && fl1->fl_end == fl2->fl_end 379 &&(fl1->fl_type == fl2->fl_type || fl2->fl_type == F_UNLCK); 380 } 381 382 extern const struct lock_manager_operations nlmsvc_lock_operations; 383 384 #endif /* LINUX_LOCKD_LOCKD_H */ 385