#include <linux/types.h>
#include <linux/utsname.h>
#include <linux/kernel.h>
+#include <linux/ktime.h>
+#include <linux/slab.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
u32 state;
};
-static struct rpc_clnt * nsm_create(void);
-
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;
-static void nsm_display_ipv4_address(const struct sockaddr *sap, char *buf,
- const size_t len)
+static inline struct sockaddr *nsm_addr(const struct nsm_handle *nsm)
{
- const struct sockaddr_in *sin = (struct sockaddr_in *)sap;
- snprintf(buf, len, "%pI4", &sin->sin_addr.s_addr);
+ return (struct sockaddr *)&nsm->sm_addr;
}
-static void nsm_display_ipv6_address(const struct sockaddr *sap, char *buf,
- const size_t len)
+static struct rpc_clnt *nsm_create(void)
{
- const struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap;
-
- if (ipv6_addr_v4mapped(&sin6->sin6_addr))
- snprintf(buf, len, "%pI4", &sin6->sin6_addr.s6_addr32[3]);
- else if (sin6->sin6_scope_id != 0)
- snprintf(buf, len, "%pI6%%%u", &sin6->sin6_addr,
- sin6->sin6_scope_id);
- else
- snprintf(buf, len, "%pI6", &sin6->sin6_addr);
-}
+ 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,
+ };
-static void nsm_display_address(const struct sockaddr *sap,
- char *buf, const size_t len)
-{
- switch (sap->sa_family) {
- case AF_INET:
- nsm_display_ipv4_address(sap, buf, len);
- break;
- case AF_INET6:
- nsm_display_ipv6_address(sap, buf, len);
- break;
- default:
- snprintf(buf, len, "unsupported address family");
- break;
- }
+ return rpc_create(&args);
}
-/*
- * Common procedure for NSMPROC_MON/NSMPROC_UNMON calls
- */
-static int
-nsm_mon_unmon(struct nsm_handle *nsm, u32 proc, struct nsm_res *res)
+static int nsm_mon_unmon(struct nsm_handle *nsm, u32 proc, struct nsm_res *res)
{
struct rpc_clnt *clnt;
int status;
nsm->sm_mon_name = nsm_use_hostnames ? nsm->sm_name : nsm->sm_addrbuf;
status = nsm_mon_unmon(nsm, NSMPROC_MON, &res);
- if (res.status != 0)
+ if (unlikely(res.status != 0))
status = -EIO;
- if (status < 0)
+ if (unlikely(status < 0)) {
printk(KERN_NOTICE "lockd: cannot monitor %s\n", nsm->sm_name);
- else
- nsm->sm_monitored = 1;
- return status;
+ 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;
}
/**
}
}
+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;
+}
+
/*
* 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.
*
- * Linux provides the raw IP address of the monitored host,
- * left in network byte order.
+ * 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 void nsm_init_private(struct nsm_handle *nsm)
{
- __be32 *p = (__be32 *)&nsm->sm_priv.data;
- *p = nsm_addr_in(nsm)->sin_addr.s_addr;
+ 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);
+}
+
+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;
}
/**
- * nsm_find - Find or create a cached nsm_handle
+ * 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
- * @create: one means create new handle if not found in cache
*
- * Behavior is modulated by the global nsm_use_hostnames variable
- * and by the @create argument.
+ * Behavior is modulated by the global nsm_use_hostnames variable.
*
- * Returns a cached nsm_handle after bumping its ref count, or if
- * @create is set, 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.
+ * 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_find(const struct sockaddr *sap, const size_t salen,
- const char *hostname, const size_t hostname_len,
- const int create)
+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 *nsm = NULL;
- struct nsm_handle *pos;
+ struct nsm_handle *cached, *new = NULL;
if (hostname && memchr(hostname, '/', hostname_len) != NULL) {
if (printk_ratelimit()) {
retry:
spin_lock(&nsm_lock);
- list_for_each_entry(pos, &nsm_handles, sm_link) {
-
- if (hostname && nsm_use_hostnames) {
- if (strlen(pos->sm_name) != hostname_len
- || memcmp(pos->sm_name, hostname, hostname_len))
- continue;
- } else if (!nlm_cmp_addr(nsm_addr(pos), sap))
- continue;
- atomic_inc(&pos->sm_count);
- kfree(nsm);
- nsm = pos;
- dprintk("lockd: found nsm_handle for %s (%s), cnt %d\n",
- pos->sm_name, pos->sm_addrbuf,
- atomic_read(&pos->sm_count));
- goto found;
+
+ 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 (nsm) {
- list_add(&nsm->sm_link, &nsm_handles);
+
+ if (new != NULL) {
+ list_add(&new->sm_link, &nsm_handles);
+ spin_unlock(&nsm_lock);
dprintk("lockd: created nsm_handle for %s (%s)\n",
- nsm->sm_name, nsm->sm_addrbuf);
- goto found;
+ new->sm_name, new->sm_addrbuf);
+ return new;
}
+
spin_unlock(&nsm_lock);
- if (!create)
+ new = nsm_create_handle(sap, salen, hostname, hostname_len);
+ if (unlikely(new == NULL))
return NULL;
+ goto retry;
+}
- nsm = kzalloc(sizeof(*nsm) + hostname_len + 1, GFP_KERNEL);
- if (nsm == NULL)
- return NULL;
+/**
+ * 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. Otherwise returns NULL if some
+ * error occurred.
+ */
+struct nsm_handle *nsm_reboot_lookup(const struct nlm_reboot *info)
+{
+ struct nsm_handle *cached;
- memcpy(nsm_addr(nsm), sap, salen);
- nsm->sm_addrlen = salen;
- nsm->sm_name = (char *) (nsm + 1);
- memcpy(nsm->sm_name, hostname, hostname_len);
- nsm->sm_name[hostname_len] = '\0';
- nsm_init_private(nsm);
- nsm_display_address((struct sockaddr *)&nsm->sm_addr,
- nsm->sm_addrbuf, sizeof(nsm->sm_addrbuf));
- atomic_set(&nsm->sm_count, 1);
- goto retry;
+ spin_lock(&nsm_lock);
-found:
+ 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);
- return nsm;
+
+ dprintk("lockd: host %s (%s) rebooted, cnt %d\n",
+ cached->sm_name, cached->sm_addrbuf,
+ atomic_read(&cached->sm_count));
+ return cached;
}
/**
}
/*
- * Create NSM client for the local host
- */
-static struct rpc_clnt *
-nsm_create(void)
-{
- struct sockaddr_in sin = {
- .sin_family = AF_INET,
- .sin_addr.s_addr = htonl(INADDR_LOOPBACK),
- .sin_port = 0,
- };
- struct rpc_create_args args = {
- .protocol = XPRT_TRANSPORT_UDP,
- .address = (struct sockaddr *)&sin,
- .addrsize = sizeof(sin),
- .servername = "localhost",
- .program = &nsm_program,
- .version = NSM_VERSION,
- .authflavor = RPC_AUTH_NULL,
- };
-
- return rpc_create(&args);
-}
-
-/*
* XDR functions for NSM.
*
* See http://www.opengroup.org/ for details on the Network