#include <linux/types.h>
#include <linux/utsname.h>
#include <linux/kernel.h>
+#include <linux/ktime.h>
+
#include <linux/sunrpc/clnt.h>
+#include <linux/sunrpc/xprtsock.h>
#include <linux/sunrpc/svc.h>
#include <linux/lockd/lockd.h>
-#include <linux/lockd/sm_inter.h>
+#include <asm/unaligned.h>
#define NLMDBG_FACILITY NLMDBG_MONITOR
+#define NSM_PROGRAM 100024
+#define NSM_VERSION 1
+
+enum {
+ NSMPROC_NULL,
+ NSMPROC_STAT,
+ NSMPROC_MON,
+ NSMPROC_UNMON,
+ NSMPROC_UNMON_ALL,
+ NSMPROC_SIMU_CRASH,
+ NSMPROC_NOTIFY,
+};
+
+struct nsm_args {
+ struct nsm_private *priv;
+ u32 prog; /* RPC callback info */
+ u32 vers;
+ u32 proc;
+
+ char *mon_name;
+};
-static struct rpc_clnt * nsm_create(void);
+struct nsm_res {
+ u32 status;
+ u32 state;
+};
static struct rpc_program nsm_program;
+static LIST_HEAD(nsm_handles);
+static DEFINE_SPINLOCK(nsm_lock);
/*
* Local NSM state
*/
-int nsm_local_state;
+u32 __read_mostly nsm_local_state;
+int __read_mostly nsm_use_hostnames;
-/*
- * Common procedure for SM_MON/SM_UNMON calls
- */
-static int
-nsm_mon_unmon(struct nsm_handle *nsm, u32 proc, struct nsm_res *res)
+static inline struct sockaddr *nsm_addr(const struct nsm_handle *nsm)
+{
+ return (struct sockaddr *)&nsm->sm_addr;
+}
+
+static struct rpc_clnt *nsm_create(void)
+{
+ struct sockaddr_in sin = {
+ .sin_family = AF_INET,
+ .sin_addr.s_addr = htonl(INADDR_LOOPBACK),
+ };
+ struct rpc_create_args args = {
+ .protocol = XPRT_TRANSPORT_UDP,
+ .address = (struct sockaddr *)&sin,
+ .addrsize = sizeof(sin),
+ .servername = "rpc.statd",
+ .program = &nsm_program,
+ .version = NSM_VERSION,
+ .authflavor = RPC_AUTH_NULL,
+ .flags = RPC_CLNT_CREATE_NOPING,
+ };
+
+ return rpc_create(&args);
+}
+
+static int nsm_mon_unmon(struct nsm_handle *nsm, u32 proc, struct nsm_res *res)
{
struct rpc_clnt *clnt;
int status;
- struct nsm_args args;
+ struct nsm_args args = {
+ .priv = &nsm->sm_priv,
+ .prog = NLM_PROGRAM,
+ .vers = 3,
+ .proc = NLMPROC_NSM_NOTIFY,
+ .mon_name = nsm->sm_mon_name,
+ };
struct rpc_message msg = {
.rpc_argp = &args,
.rpc_resp = res,
clnt = nsm_create();
if (IS_ERR(clnt)) {
status = PTR_ERR(clnt);
+ dprintk("lockd: failed to create NSM upcall transport, "
+ "status=%d\n", status);
goto out;
}
- memset(&args, 0, sizeof(args));
- args.mon_name = nsm->sm_name;
- args.addr = nsm->sm_addr.sin_addr.s_addr;
- args.prog = NLM_PROGRAM;
- args.vers = 3;
- args.proc = NLMPROC_NSM_NOTIFY;
memset(res, 0, sizeof(*res));
msg.rpc_proc = &clnt->cl_procinfo[proc];
status = rpc_call_sync(clnt, &msg, 0);
if (status < 0)
- printk(KERN_DEBUG "nsm_mon_unmon: rpc failed, status=%d\n",
- status);
+ dprintk("lockd: NSM upcall RPC failed, status=%d\n",
+ status);
else
status = 0;
+ rpc_shutdown_client(clnt);
out:
return status;
}
-/*
- * Set up monitoring of a remote host
+/**
+ * nsm_monitor - Notify a peer in case we reboot
+ * @host: pointer to nlm_host of peer to notify
+ *
+ * If this peer is not already monitored, this function sends an
+ * upcall to the local rpc.statd to record the name/address of
+ * the peer to notify in case we reboot.
+ *
+ * Returns zero if the peer is monitored by the local rpc.statd;
+ * otherwise a negative errno value is returned.
*/
-int
-nsm_monitor(struct nlm_host *host)
+int nsm_monitor(const struct nlm_host *host)
{
struct nsm_handle *nsm = host->h_nsmhandle;
struct nsm_res res;
int status;
- dprintk("lockd: nsm_monitor(%s)\n", host->h_name);
- BUG_ON(nsm == NULL);
+ dprintk("lockd: nsm_monitor(%s)\n", nsm->sm_name);
if (nsm->sm_monitored)
return 0;
- status = nsm_mon_unmon(nsm, SM_MON, &res);
+ /*
+ * Choose whether to record the caller_name or IP address of
+ * this peer in the local rpc.statd's database.
+ */
+ nsm->sm_mon_name = nsm_use_hostnames ? nsm->sm_name : nsm->sm_addrbuf;
+
+ status = nsm_mon_unmon(nsm, NSMPROC_MON, &res);
+ if (unlikely(res.status != 0))
+ status = -EIO;
+ if (unlikely(status < 0)) {
+ printk(KERN_NOTICE "lockd: cannot monitor %s\n", nsm->sm_name);
+ return status;
+ }
- if (status < 0 || res.status != 0)
- printk(KERN_NOTICE "lockd: cannot monitor %s\n", host->h_name);
- else
- nsm->sm_monitored = 1;
- return status;
+ nsm->sm_monitored = 1;
+ if (unlikely(nsm_local_state != res.state)) {
+ nsm_local_state = res.state;
+ dprintk("lockd: NSM state changed to %d\n", nsm_local_state);
+ }
+ return 0;
}
-/*
- * Cease to monitor remote host
+/**
+ * nsm_unmonitor - Unregister peer notification
+ * @host: pointer to nlm_host of peer to stop monitoring
+ *
+ * If this peer is monitored, this function sends an upcall to
+ * tell the local rpc.statd not to send this peer a notification
+ * when we reboot.
*/
-int
-nsm_unmonitor(struct nlm_host *host)
+void nsm_unmonitor(const struct nlm_host *host)
{
struct nsm_handle *nsm = host->h_nsmhandle;
struct nsm_res res;
- int status = 0;
-
- if (nsm == NULL)
- return 0;
- host->h_nsmhandle = NULL;
+ int status;
if (atomic_read(&nsm->sm_count) == 1
&& nsm->sm_monitored && !nsm->sm_sticky) {
- dprintk("lockd: nsm_unmonitor(%s)\n", host->h_name);
+ dprintk("lockd: nsm_unmonitor(%s)\n", nsm->sm_name);
- status = nsm_mon_unmon(nsm, SM_UNMON, &res);
+ status = nsm_mon_unmon(nsm, NSMPROC_UNMON, &res);
+ if (res.status != 0)
+ status = -EIO;
if (status < 0)
printk(KERN_NOTICE "lockd: cannot unmonitor %s\n",
- host->h_name);
+ nsm->sm_name);
else
nsm->sm_monitored = 0;
}
- nsm_release(nsm);
- return status;
+}
+
+static struct nsm_handle *nsm_lookup_hostname(const char *hostname,
+ const size_t len)
+{
+ struct nsm_handle *nsm;
+
+ list_for_each_entry(nsm, &nsm_handles, sm_link)
+ if (strlen(nsm->sm_name) == len &&
+ memcmp(nsm->sm_name, hostname, len) == 0)
+ return nsm;
+ return NULL;
+}
+
+static struct nsm_handle *nsm_lookup_addr(const struct sockaddr *sap)
+{
+ struct nsm_handle *nsm;
+
+ list_for_each_entry(nsm, &nsm_handles, sm_link)
+ if (rpc_cmp_addr(nsm_addr(nsm), sap))
+ return nsm;
+ return NULL;
+}
+
+static struct nsm_handle *nsm_lookup_priv(const struct nsm_private *priv)
+{
+ struct nsm_handle *nsm;
+
+ list_for_each_entry(nsm, &nsm_handles, sm_link)
+ if (memcmp(nsm->sm_priv.data, priv->data,
+ sizeof(priv->data)) == 0)
+ return nsm;
+ return NULL;
}
/*
- * Create NSM client for the local host
+ * Construct a unique cookie to match this nsm_handle to this monitored
+ * host. It is passed to the local rpc.statd via NSMPROC_MON, and
+ * returned via NLMPROC_SM_NOTIFY, in the "priv" field of these
+ * requests.
+ *
+ * The NSM protocol requires that these cookies be unique while the
+ * system is running. We prefer a stronger requirement of making them
+ * unique across reboots. If user space bugs cause a stale cookie to
+ * be sent to the kernel, it could cause the wrong host to lose its
+ * lock state if cookies were not unique across reboots.
+ *
+ * The cookies are exposed only to local user space via loopback. They
+ * do not appear on the physical network. If we want greater security
+ * for some reason, nsm_init_private() could perform a one-way hash to
+ * obscure the contents of the cookie.
*/
-static struct rpc_clnt *
-nsm_create(void)
+static void nsm_init_private(struct nsm_handle *nsm)
{
- struct sockaddr_in sin = {
- .sin_family = AF_INET,
- .sin_addr.s_addr = htonl(INADDR_LOOPBACK),
- .sin_port = 0,
- };
- struct rpc_create_args args = {
- .protocol = IPPROTO_UDP,
- .address = (struct sockaddr *)&sin,
- .addrsize = sizeof(sin),
- .servername = "localhost",
- .program = &nsm_program,
- .version = SM_VERSION,
- .authflavor = RPC_AUTH_NULL,
- .flags = (RPC_CLNT_CREATE_ONESHOT),
- };
+ u64 *p = (u64 *)&nsm->sm_priv.data;
+ struct timespec ts;
+ s64 ns;
+
+ ktime_get_ts(&ts);
+ ns = timespec_to_ns(&ts);
+ put_unaligned(ns, p);
+ put_unaligned((unsigned long)nsm, p + 1);
+}
- return rpc_create(&args);
+static struct nsm_handle *nsm_create_handle(const struct sockaddr *sap,
+ const size_t salen,
+ const char *hostname,
+ const size_t hostname_len)
+{
+ struct nsm_handle *new;
+
+ new = kzalloc(sizeof(*new) + hostname_len + 1, GFP_KERNEL);
+ if (unlikely(new == NULL))
+ return NULL;
+
+ atomic_set(&new->sm_count, 1);
+ new->sm_name = (char *)(new + 1);
+ memcpy(nsm_addr(new), sap, salen);
+ new->sm_addrlen = salen;
+ nsm_init_private(new);
+
+ if (rpc_ntop(nsm_addr(new), new->sm_addrbuf,
+ sizeof(new->sm_addrbuf)) == 0)
+ (void)snprintf(new->sm_addrbuf, sizeof(new->sm_addrbuf),
+ "unsupported address family");
+ memcpy(new->sm_name, hostname, hostname_len);
+ new->sm_name[hostname_len] = '\0';
+
+ return new;
}
-/*
- * XDR functions for NSM.
+/**
+ * nsm_get_handle - Find or create a cached nsm_handle
+ * @sap: pointer to socket address of handle to find
+ * @salen: length of socket address
+ * @hostname: pointer to C string containing hostname to find
+ * @hostname_len: length of C string
+ *
+ * Behavior is modulated by the global nsm_use_hostnames variable.
+ *
+ * Returns a cached nsm_handle after bumping its ref count, or
+ * returns a fresh nsm_handle if a handle that matches @sap and/or
+ * @hostname cannot be found in the handle cache. Returns NULL if
+ * an error occurs.
*/
+struct nsm_handle *nsm_get_handle(const struct sockaddr *sap,
+ const size_t salen, const char *hostname,
+ const size_t hostname_len)
+{
+ struct nsm_handle *cached, *new = NULL;
+
+ if (hostname && memchr(hostname, '/', hostname_len) != NULL) {
+ if (printk_ratelimit()) {
+ printk(KERN_WARNING "Invalid hostname \"%.*s\" "
+ "in NFS lock request\n",
+ (int)hostname_len, hostname);
+ }
+ return NULL;
+ }
+
+retry:
+ spin_lock(&nsm_lock);
+
+ if (nsm_use_hostnames && hostname != NULL)
+ cached = nsm_lookup_hostname(hostname, hostname_len);
+ else
+ cached = nsm_lookup_addr(sap);
+
+ if (cached != NULL) {
+ atomic_inc(&cached->sm_count);
+ spin_unlock(&nsm_lock);
+ kfree(new);
+ dprintk("lockd: found nsm_handle for %s (%s), "
+ "cnt %d\n", cached->sm_name,
+ cached->sm_addrbuf,
+ atomic_read(&cached->sm_count));
+ return cached;
+ }
+
+ if (new != NULL) {
+ list_add(&new->sm_link, &nsm_handles);
+ spin_unlock(&nsm_lock);
+ dprintk("lockd: created nsm_handle for %s (%s)\n",
+ new->sm_name, new->sm_addrbuf);
+ return new;
+ }
+
+ spin_unlock(&nsm_lock);
-static u32 *
-xdr_encode_common(struct rpc_rqst *rqstp, u32 *p, struct nsm_args *argp)
+ new = nsm_create_handle(sap, salen, hostname, hostname_len);
+ if (unlikely(new == NULL))
+ return NULL;
+ goto retry;
+}
+
+/**
+ * nsm_reboot_lookup - match NLMPROC_SM_NOTIFY arguments to an nsm_handle
+ * @info: pointer to NLMPROC_SM_NOTIFY arguments
+ *
+ * Returns a matching nsm_handle if found in the nsm cache; the returned
+ * nsm_handle's reference count is bumped and sm_monitored is cleared.
+ * Otherwise returns NULL if some error occurred.
+ */
+struct nsm_handle *nsm_reboot_lookup(const struct nlm_reboot *info)
{
- char buffer[20], *name;
+ struct nsm_handle *cached;
+
+ spin_lock(&nsm_lock);
+
+ cached = nsm_lookup_priv(&info->priv);
+ if (unlikely(cached == NULL)) {
+ spin_unlock(&nsm_lock);
+ dprintk("lockd: never saw rebooted peer '%.*s' before\n",
+ info->len, info->mon);
+ return cached;
+ }
+
+ atomic_inc(&cached->sm_count);
+ spin_unlock(&nsm_lock);
/*
- * Use the dotted-quad IP address of the remote host as
- * identifier. Linux statd always looks up the canonical
- * hostname first for whatever remote hostname it receives,
- * so this works alright.
+ * During subsequent lock activity, force a fresh
+ * notification to be set up for this host.
*/
- if (nsm_use_hostnames) {
- name = argp->mon_name;
- } else {
- sprintf(buffer, "%u.%u.%u.%u", NIPQUAD(argp->addr));
- name = buffer;
+ cached->sm_monitored = 0;
+
+ dprintk("lockd: host %s (%s) rebooted, cnt %d\n",
+ cached->sm_name, cached->sm_addrbuf,
+ atomic_read(&cached->sm_count));
+ return cached;
+}
+
+/**
+ * nsm_release - Release an NSM handle
+ * @nsm: pointer to handle to be released
+ *
+ */
+void nsm_release(struct nsm_handle *nsm)
+{
+ if (atomic_dec_and_lock(&nsm->sm_count, &nsm_lock)) {
+ list_del(&nsm->sm_link);
+ spin_unlock(&nsm_lock);
+ dprintk("lockd: destroyed nsm_handle for %s (%s)\n",
+ nsm->sm_name, nsm->sm_addrbuf);
+ kfree(nsm);
}
- if (!(p = xdr_encode_string(p, name))
- || !(p = xdr_encode_string(p, utsname()->nodename)))
- return ERR_PTR(-EIO);
+}
+
+/*
+ * XDR functions for NSM.
+ *
+ * See http://www.opengroup.org/ for details on the Network
+ * Status Monitor wire protocol.
+ */
+
+static int encode_nsm_string(struct xdr_stream *xdr, const char *string)
+{
+ const u32 len = strlen(string);
+ __be32 *p;
+
+ if (unlikely(len > SM_MAXSTRLEN))
+ return -EIO;
+ p = xdr_reserve_space(xdr, sizeof(u32) + len);
+ if (unlikely(p == NULL))
+ return -EIO;
+ xdr_encode_opaque(p, string, len);
+ return 0;
+}
+
+/*
+ * "mon_name" specifies the host to be monitored.
+ */
+static int encode_mon_name(struct xdr_stream *xdr, const struct nsm_args *argp)
+{
+ return encode_nsm_string(xdr, argp->mon_name);
+}
+
+/*
+ * The "my_id" argument specifies the hostname and RPC procedure
+ * to be called when the status manager receives notification
+ * (via the NLMPROC_SM_NOTIFY call) that the state of host "mon_name"
+ * has changed.
+ */
+static int encode_my_id(struct xdr_stream *xdr, const struct nsm_args *argp)
+{
+ int status;
+ __be32 *p;
+
+ status = encode_nsm_string(xdr, utsname()->nodename);
+ if (unlikely(status != 0))
+ return status;
+ p = xdr_reserve_space(xdr, 3 * sizeof(u32));
+ if (unlikely(p == NULL))
+ return -EIO;
*p++ = htonl(argp->prog);
*p++ = htonl(argp->vers);
*p++ = htonl(argp->proc);
+ return 0;
+}
+
+/*
+ * The "mon_id" argument specifies the non-private arguments
+ * of an NSMPROC_MON or NSMPROC_UNMON call.
+ */
+static int encode_mon_id(struct xdr_stream *xdr, const struct nsm_args *argp)
+{
+ int status;
- return p;
+ status = encode_mon_name(xdr, argp);
+ if (unlikely(status != 0))
+ return status;
+ return encode_my_id(xdr, argp);
}
-static int
-xdr_encode_mon(struct rpc_rqst *rqstp, u32 *p, struct nsm_args *argp)
+/*
+ * The "priv" argument may contain private information required
+ * by the NSMPROC_MON call. This information will be supplied in the
+ * NLMPROC_SM_NOTIFY call.
+ */
+static int encode_priv(struct xdr_stream *xdr, const struct nsm_args *argp)
{
- p = xdr_encode_common(rqstp, p, argp);
- if (IS_ERR(p))
- return PTR_ERR(p);
-
- /* Surprise - there may even be room for an IPv6 address now */
- *p++ = argp->addr;
- *p++ = 0;
- *p++ = 0;
- *p++ = 0;
- rqstp->rq_slen = xdr_adjust_iovec(rqstp->rq_svec, p);
+ __be32 *p;
+
+ p = xdr_reserve_space(xdr, SM_PRIV_SIZE);
+ if (unlikely(p == NULL))
+ return -EIO;
+ xdr_encode_opaque_fixed(p, argp->priv->data, SM_PRIV_SIZE);
return 0;
}
-static int
-xdr_encode_unmon(struct rpc_rqst *rqstp, u32 *p, struct nsm_args *argp)
+static int xdr_enc_mon(struct rpc_rqst *req, __be32 *p,
+ const struct nsm_args *argp)
{
- p = xdr_encode_common(rqstp, p, argp);
- if (IS_ERR(p))
- return PTR_ERR(p);
- rqstp->rq_slen = xdr_adjust_iovec(rqstp->rq_svec, p);
- return 0;
+ struct xdr_stream xdr;
+ int status;
+
+ xdr_init_encode(&xdr, &req->rq_snd_buf, p);
+ status = encode_mon_id(&xdr, argp);
+ if (unlikely(status))
+ return status;
+ return encode_priv(&xdr, argp);
}
-static int
-xdr_decode_stat_res(struct rpc_rqst *rqstp, u32 *p, struct nsm_res *resp)
+static int xdr_enc_unmon(struct rpc_rqst *req, __be32 *p,
+ const struct nsm_args *argp)
{
+ struct xdr_stream xdr;
+
+ xdr_init_encode(&xdr, &req->rq_snd_buf, p);
+ return encode_mon_id(&xdr, argp);
+}
+
+static int xdr_dec_stat_res(struct rpc_rqst *rqstp, __be32 *p,
+ struct nsm_res *resp)
+{
+ struct xdr_stream xdr;
+
+ xdr_init_decode(&xdr, &rqstp->rq_rcv_buf, p);
+ p = xdr_inline_decode(&xdr, 2 * sizeof(u32));
+ if (unlikely(p == NULL))
+ return -EIO;
resp->status = ntohl(*p++);
- resp->state = ntohl(*p++);
- dprintk("nsm: xdr_decode_stat_res status %d state %d\n",
+ resp->state = ntohl(*p);
+
+ dprintk("lockd: xdr_dec_stat_res status %d state %d\n",
resp->status, resp->state);
return 0;
}
-static int
-xdr_decode_stat(struct rpc_rqst *rqstp, u32 *p, struct nsm_res *resp)
+static int xdr_dec_stat(struct rpc_rqst *rqstp, __be32 *p,
+ struct nsm_res *resp)
{
- resp->state = ntohl(*p++);
+ struct xdr_stream xdr;
+
+ xdr_init_decode(&xdr, &rqstp->rq_rcv_buf, p);
+ p = xdr_inline_decode(&xdr, sizeof(u32));
+ if (unlikely(p == NULL))
+ return -EIO;
+ resp->state = ntohl(*p);
+
+ dprintk("lockd: xdr_dec_stat state %d\n", resp->state);
return 0;
}
#define SM_my_name_sz (1+XDR_QUADLEN(SM_MAXSTRLEN))
-#define SM_my_id_sz (3+1+SM_my_name_sz)
-#define SM_mon_id_sz (1+XDR_QUADLEN(20)+SM_my_id_sz)
-#define SM_mon_sz (SM_mon_id_sz+4)
+#define SM_my_id_sz (SM_my_name_sz+3)
+#define SM_mon_name_sz (1+XDR_QUADLEN(SM_MAXSTRLEN))
+#define SM_mon_id_sz (SM_mon_name_sz+SM_my_id_sz)
+#define SM_priv_sz (XDR_QUADLEN(SM_PRIV_SIZE))
+#define SM_mon_sz (SM_mon_id_sz+SM_priv_sz)
#define SM_monres_sz 2
#define SM_unmonres_sz 1
-#ifndef MAX
-# define MAX(a, b) (((a) > (b))? (a) : (b))
-#endif
-
static struct rpc_procinfo nsm_procedures[] = {
-[SM_MON] = {
- .p_proc = SM_MON,
- .p_encode = (kxdrproc_t) xdr_encode_mon,
- .p_decode = (kxdrproc_t) xdr_decode_stat_res,
- .p_bufsiz = MAX(SM_mon_sz, SM_monres_sz) << 2,
- .p_statidx = SM_MON,
+[NSMPROC_MON] = {
+ .p_proc = NSMPROC_MON,
+ .p_encode = (kxdrproc_t)xdr_enc_mon,
+ .p_decode = (kxdrproc_t)xdr_dec_stat_res,
+ .p_arglen = SM_mon_sz,
+ .p_replen = SM_monres_sz,
+ .p_statidx = NSMPROC_MON,
.p_name = "MONITOR",
},
-[SM_UNMON] = {
- .p_proc = SM_UNMON,
- .p_encode = (kxdrproc_t) xdr_encode_unmon,
- .p_decode = (kxdrproc_t) xdr_decode_stat,
- .p_bufsiz = MAX(SM_mon_id_sz, SM_unmonres_sz) << 2,
- .p_statidx = SM_UNMON,
+[NSMPROC_UNMON] = {
+ .p_proc = NSMPROC_UNMON,
+ .p_encode = (kxdrproc_t)xdr_enc_unmon,
+ .p_decode = (kxdrproc_t)xdr_dec_stat,
+ .p_arglen = SM_mon_id_sz,
+ .p_replen = SM_unmonres_sz,
+ .p_statidx = NSMPROC_UNMON,
.p_name = "UNMONITOR",
},
};
static struct rpc_program nsm_program = {
.name = "statd",
- .number = SM_PROGRAM,
+ .number = NSM_PROGRAM,
.nrvers = ARRAY_SIZE(nsm_version),
.version = nsm_version,
.stats = &nsm_stats
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff