4 * The kernel statd client.
6 * Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de>
9 #include <linux/types.h>
10 #include <linux/utsname.h>
11 #include <linux/kernel.h>
12 #include <linux/sunrpc/clnt.h>
13 #include <linux/sunrpc/xprtsock.h>
14 #include <linux/sunrpc/svc.h>
15 #include <linux/lockd/lockd.h>
16 #include <linux/lockd/sm_inter.h>
19 #define NLMDBG_FACILITY NLMDBG_MONITOR
20 #define NSM_PROGRAM 100024
34 struct nsm_private *priv;
35 u32 prog; /* RPC callback info */
47 static struct rpc_clnt * nsm_create(void);
49 static struct rpc_program nsm_program;
50 static LIST_HEAD(nsm_handles);
51 static DEFINE_SPINLOCK(nsm_lock);
58 static void nsm_display_ipv4_address(const struct sockaddr *sap, char *buf,
61 const struct sockaddr_in *sin = (struct sockaddr_in *)sap;
62 snprintf(buf, len, "%pI4", &sin->sin_addr.s_addr);
65 static void nsm_display_ipv6_address(const struct sockaddr *sap, char *buf,
68 const struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
70 if (ipv6_addr_v4mapped(&sin6->sin6_addr))
71 snprintf(buf, len, "%pI4", &sin6->sin6_addr.s6_addr32[3]);
72 else if (sin6->sin6_scope_id != 0)
73 snprintf(buf, len, "%pI6%%%u", &sin6->sin6_addr,
76 snprintf(buf, len, "%pI6", &sin6->sin6_addr);
79 static void nsm_display_address(const struct sockaddr *sap,
80 char *buf, const size_t len)
82 switch (sap->sa_family) {
84 nsm_display_ipv4_address(sap, buf, len);
87 nsm_display_ipv6_address(sap, buf, len);
90 snprintf(buf, len, "unsupported address family");
96 * Common procedure for NSMPROC_MON/NSMPROC_UNMON calls
99 nsm_mon_unmon(struct nsm_handle *nsm, u32 proc, struct nsm_res *res)
101 struct rpc_clnt *clnt;
103 struct nsm_args args = {
104 .priv = &nsm->sm_priv,
107 .proc = NLMPROC_NSM_NOTIFY,
108 .mon_name = nsm->sm_mon_name,
110 struct rpc_message msg = {
117 status = PTR_ERR(clnt);
118 dprintk("lockd: failed to create NSM upcall transport, "
119 "status=%d\n", status);
123 memset(res, 0, sizeof(*res));
125 msg.rpc_proc = &clnt->cl_procinfo[proc];
126 status = rpc_call_sync(clnt, &msg, 0);
128 dprintk("lockd: NSM upcall RPC failed, status=%d\n",
132 rpc_shutdown_client(clnt);
138 * nsm_monitor - Notify a peer in case we reboot
139 * @host: pointer to nlm_host of peer to notify
141 * If this peer is not already monitored, this function sends an
142 * upcall to the local rpc.statd to record the name/address of
143 * the peer to notify in case we reboot.
145 * Returns zero if the peer is monitored by the local rpc.statd;
146 * otherwise a negative errno value is returned.
148 int nsm_monitor(const struct nlm_host *host)
150 struct nsm_handle *nsm = host->h_nsmhandle;
154 dprintk("lockd: nsm_monitor(%s)\n", nsm->sm_name);
156 if (nsm->sm_monitored)
160 * Choose whether to record the caller_name or IP address of
161 * this peer in the local rpc.statd's database.
163 nsm->sm_mon_name = nsm_use_hostnames ? nsm->sm_name : nsm->sm_addrbuf;
165 status = nsm_mon_unmon(nsm, NSMPROC_MON, &res);
169 printk(KERN_NOTICE "lockd: cannot monitor %s\n", nsm->sm_name);
171 nsm->sm_monitored = 1;
176 * nsm_unmonitor - Unregister peer notification
177 * @host: pointer to nlm_host of peer to stop monitoring
179 * If this peer is monitored, this function sends an upcall to
180 * tell the local rpc.statd not to send this peer a notification
183 void nsm_unmonitor(const struct nlm_host *host)
185 struct nsm_handle *nsm = host->h_nsmhandle;
189 if (atomic_read(&nsm->sm_count) == 1
190 && nsm->sm_monitored && !nsm->sm_sticky) {
191 dprintk("lockd: nsm_unmonitor(%s)\n", nsm->sm_name);
193 status = nsm_mon_unmon(nsm, NSMPROC_UNMON, &res);
197 printk(KERN_NOTICE "lockd: cannot unmonitor %s\n",
200 nsm->sm_monitored = 0;
204 static struct nsm_handle *nsm_lookup_hostname(const char *hostname,
207 struct nsm_handle *nsm;
209 list_for_each_entry(nsm, &nsm_handles, sm_link)
210 if (strlen(nsm->sm_name) == len &&
211 memcmp(nsm->sm_name, hostname, len) == 0)
216 static struct nsm_handle *nsm_lookup_addr(const struct sockaddr *sap)
218 struct nsm_handle *nsm;
220 list_for_each_entry(nsm, &nsm_handles, sm_link)
221 if (nlm_cmp_addr(nsm_addr(nsm), sap))
226 static struct nsm_handle *nsm_lookup_priv(const struct nsm_private *priv)
228 struct nsm_handle *nsm;
230 list_for_each_entry(nsm, &nsm_handles, sm_link)
231 if (memcmp(nsm->sm_priv.data, priv->data,
232 sizeof(priv->data)) == 0)
238 * Construct a unique cookie to match this nsm_handle to this monitored
239 * host. It is passed to the local rpc.statd via NSMPROC_MON, and
240 * returned via NLMPROC_SM_NOTIFY, in the "priv" field of these
243 * Linux provides the raw IP address of the monitored host,
244 * left in network byte order.
246 static void nsm_init_private(struct nsm_handle *nsm)
248 __be32 *p = (__be32 *)&nsm->sm_priv.data;
249 *p = nsm_addr_in(nsm)->sin_addr.s_addr;
252 static struct nsm_handle *nsm_create_handle(const struct sockaddr *sap,
254 const char *hostname,
255 const size_t hostname_len)
257 struct nsm_handle *new;
259 new = kzalloc(sizeof(*new) + hostname_len + 1, GFP_KERNEL);
260 if (unlikely(new == NULL))
263 atomic_set(&new->sm_count, 1);
264 new->sm_name = (char *)(new + 1);
265 memcpy(nsm_addr(new), sap, salen);
266 new->sm_addrlen = salen;
267 nsm_init_private(new);
268 nsm_display_address((const struct sockaddr *)&new->sm_addr,
269 new->sm_addrbuf, sizeof(new->sm_addrbuf));
270 memcpy(new->sm_name, hostname, hostname_len);
271 new->sm_name[hostname_len] = '\0';
277 * nsm_get_handle - Find or create a cached nsm_handle
278 * @sap: pointer to socket address of handle to find
279 * @salen: length of socket address
280 * @hostname: pointer to C string containing hostname to find
281 * @hostname_len: length of C string
283 * Behavior is modulated by the global nsm_use_hostnames variable.
285 * Returns a cached nsm_handle after bumping its ref count, or
286 * returns a fresh nsm_handle if a handle that matches @sap and/or
287 * @hostname cannot be found in the handle cache. Returns NULL if
290 struct nsm_handle *nsm_get_handle(const struct sockaddr *sap,
291 const size_t salen, const char *hostname,
292 const size_t hostname_len)
294 struct nsm_handle *cached, *new = NULL;
296 if (hostname && memchr(hostname, '/', hostname_len) != NULL) {
297 if (printk_ratelimit()) {
298 printk(KERN_WARNING "Invalid hostname \"%.*s\" "
299 "in NFS lock request\n",
300 (int)hostname_len, hostname);
306 spin_lock(&nsm_lock);
308 if (nsm_use_hostnames && hostname != NULL)
309 cached = nsm_lookup_hostname(hostname, hostname_len);
311 cached = nsm_lookup_addr(sap);
313 if (cached != NULL) {
314 atomic_inc(&cached->sm_count);
315 spin_unlock(&nsm_lock);
317 dprintk("lockd: found nsm_handle for %s (%s), "
318 "cnt %d\n", cached->sm_name,
320 atomic_read(&cached->sm_count));
325 list_add(&new->sm_link, &nsm_handles);
326 spin_unlock(&nsm_lock);
327 dprintk("lockd: created nsm_handle for %s (%s)\n",
328 new->sm_name, new->sm_addrbuf);
332 spin_unlock(&nsm_lock);
334 new = nsm_create_handle(sap, salen, hostname, hostname_len);
335 if (unlikely(new == NULL))
341 * nsm_reboot_lookup - match NLMPROC_SM_NOTIFY arguments to an nsm_handle
342 * @info: pointer to NLMPROC_SM_NOTIFY arguments
344 * Returns a matching nsm_handle if found in the nsm cache; the returned
345 * nsm_handle's reference count is bumped and sm_monitored is cleared.
346 * Otherwise returns NULL if some error occurred.
348 struct nsm_handle *nsm_reboot_lookup(const struct nlm_reboot *info)
350 struct nsm_handle *cached;
352 spin_lock(&nsm_lock);
354 if (nsm_use_hostnames && info->mon != NULL)
355 cached = nsm_lookup_hostname(info->mon, info->len);
357 cached = nsm_lookup_priv(&info->priv);
359 if (unlikely(cached == NULL)) {
360 spin_unlock(&nsm_lock);
361 dprintk("lockd: never saw rebooted peer '%.*s' before\n",
362 info->len, info->mon);
366 atomic_inc(&cached->sm_count);
367 spin_unlock(&nsm_lock);
370 * During subsequent lock activity, force a fresh
371 * notification to be set up for this host.
373 cached->sm_monitored = 0;
375 dprintk("lockd: host %s (%s) rebooted, cnt %d\n",
376 cached->sm_name, cached->sm_addrbuf,
377 atomic_read(&cached->sm_count));
382 * nsm_release - Release an NSM handle
383 * @nsm: pointer to handle to be released
386 void nsm_release(struct nsm_handle *nsm)
388 if (atomic_dec_and_lock(&nsm->sm_count, &nsm_lock)) {
389 list_del(&nsm->sm_link);
390 spin_unlock(&nsm_lock);
391 dprintk("lockd: destroyed nsm_handle for %s (%s)\n",
392 nsm->sm_name, nsm->sm_addrbuf);
398 * Create NSM client for the local host
400 static struct rpc_clnt *
403 struct sockaddr_in sin = {
404 .sin_family = AF_INET,
405 .sin_addr.s_addr = htonl(INADDR_LOOPBACK),
408 struct rpc_create_args args = {
409 .protocol = XPRT_TRANSPORT_UDP,
410 .address = (struct sockaddr *)&sin,
411 .addrsize = sizeof(sin),
412 .servername = "localhost",
413 .program = &nsm_program,
414 .version = NSM_VERSION,
415 .authflavor = RPC_AUTH_NULL,
418 return rpc_create(&args);
422 * XDR functions for NSM.
424 * See http://www.opengroup.org/ for details on the Network
425 * Status Monitor wire protocol.
428 static int encode_nsm_string(struct xdr_stream *xdr, const char *string)
430 const u32 len = strlen(string);
433 if (unlikely(len > SM_MAXSTRLEN))
435 p = xdr_reserve_space(xdr, sizeof(u32) + len);
436 if (unlikely(p == NULL))
438 xdr_encode_opaque(p, string, len);
443 * "mon_name" specifies the host to be monitored.
445 static int encode_mon_name(struct xdr_stream *xdr, const struct nsm_args *argp)
447 return encode_nsm_string(xdr, argp->mon_name);
451 * The "my_id" argument specifies the hostname and RPC procedure
452 * to be called when the status manager receives notification
453 * (via the NLMPROC_SM_NOTIFY call) that the state of host "mon_name"
456 static int encode_my_id(struct xdr_stream *xdr, const struct nsm_args *argp)
461 status = encode_nsm_string(xdr, utsname()->nodename);
462 if (unlikely(status != 0))
464 p = xdr_reserve_space(xdr, 3 * sizeof(u32));
465 if (unlikely(p == NULL))
467 *p++ = htonl(argp->prog);
468 *p++ = htonl(argp->vers);
469 *p++ = htonl(argp->proc);
474 * The "mon_id" argument specifies the non-private arguments
475 * of an NSMPROC_MON or NSMPROC_UNMON call.
477 static int encode_mon_id(struct xdr_stream *xdr, const struct nsm_args *argp)
481 status = encode_mon_name(xdr, argp);
482 if (unlikely(status != 0))
484 return encode_my_id(xdr, argp);
488 * The "priv" argument may contain private information required
489 * by the NSMPROC_MON call. This information will be supplied in the
490 * NLMPROC_SM_NOTIFY call.
492 static int encode_priv(struct xdr_stream *xdr, const struct nsm_args *argp)
496 p = xdr_reserve_space(xdr, SM_PRIV_SIZE);
497 if (unlikely(p == NULL))
499 xdr_encode_opaque_fixed(p, argp->priv->data, SM_PRIV_SIZE);
503 static int xdr_enc_mon(struct rpc_rqst *req, __be32 *p,
504 const struct nsm_args *argp)
506 struct xdr_stream xdr;
509 xdr_init_encode(&xdr, &req->rq_snd_buf, p);
510 status = encode_mon_id(&xdr, argp);
511 if (unlikely(status))
513 return encode_priv(&xdr, argp);
516 static int xdr_enc_unmon(struct rpc_rqst *req, __be32 *p,
517 const struct nsm_args *argp)
519 struct xdr_stream xdr;
521 xdr_init_encode(&xdr, &req->rq_snd_buf, p);
522 return encode_mon_id(&xdr, argp);
525 static int xdr_dec_stat_res(struct rpc_rqst *rqstp, __be32 *p,
526 struct nsm_res *resp)
528 struct xdr_stream xdr;
530 xdr_init_decode(&xdr, &rqstp->rq_rcv_buf, p);
531 p = xdr_inline_decode(&xdr, 2 * sizeof(u32));
532 if (unlikely(p == NULL))
534 resp->status = ntohl(*p++);
535 resp->state = ntohl(*p);
537 dprintk("lockd: xdr_dec_stat_res status %d state %d\n",
538 resp->status, resp->state);
542 static int xdr_dec_stat(struct rpc_rqst *rqstp, __be32 *p,
543 struct nsm_res *resp)
545 struct xdr_stream xdr;
547 xdr_init_decode(&xdr, &rqstp->rq_rcv_buf, p);
548 p = xdr_inline_decode(&xdr, sizeof(u32));
549 if (unlikely(p == NULL))
551 resp->state = ntohl(*p);
553 dprintk("lockd: xdr_dec_stat state %d\n", resp->state);
557 #define SM_my_name_sz (1+XDR_QUADLEN(SM_MAXSTRLEN))
558 #define SM_my_id_sz (SM_my_name_sz+3)
559 #define SM_mon_name_sz (1+XDR_QUADLEN(SM_MAXSTRLEN))
560 #define SM_mon_id_sz (SM_mon_name_sz+SM_my_id_sz)
561 #define SM_priv_sz (XDR_QUADLEN(SM_PRIV_SIZE))
562 #define SM_mon_sz (SM_mon_id_sz+SM_priv_sz)
563 #define SM_monres_sz 2
564 #define SM_unmonres_sz 1
566 static struct rpc_procinfo nsm_procedures[] = {
568 .p_proc = NSMPROC_MON,
569 .p_encode = (kxdrproc_t)xdr_enc_mon,
570 .p_decode = (kxdrproc_t)xdr_dec_stat_res,
571 .p_arglen = SM_mon_sz,
572 .p_replen = SM_monres_sz,
573 .p_statidx = NSMPROC_MON,
577 .p_proc = NSMPROC_UNMON,
578 .p_encode = (kxdrproc_t)xdr_enc_unmon,
579 .p_decode = (kxdrproc_t)xdr_dec_stat,
580 .p_arglen = SM_mon_id_sz,
581 .p_replen = SM_unmonres_sz,
582 .p_statidx = NSMPROC_UNMON,
583 .p_name = "UNMONITOR",
587 static struct rpc_version nsm_version1 = {
589 .nrprocs = ARRAY_SIZE(nsm_procedures),
590 .procs = nsm_procedures
593 static struct rpc_version * nsm_version[] = {
597 static struct rpc_stat nsm_stats;
599 static struct rpc_program nsm_program = {
601 .number = NSM_PROGRAM,
602 .nrvers = ARRAY_SIZE(nsm_version),
603 .version = nsm_version,