#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>
-
#define NLMDBG_FACILITY NLMDBG_MONITOR
#define NSM_PROGRAM 100024
};
struct nsm_args {
- __be32 addr; /* remote address */
+ struct nsm_private *priv;
u32 prog; /* RPC callback info */
u32 vers;
u32 proc;
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;
+int __read_mostly nsm_local_state;
+int __read_mostly nsm_use_hostnames;
-/*
- * Common procedure for NSMPROC_MON/NSMPROC_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 void nsm_display_ipv4_address(const struct sockaddr *sap, char *buf,
+ const size_t len)
+{
+ const struct sockaddr_in *sin = (struct sockaddr_in *)sap;
+ snprintf(buf, len, "%pI4", &sin->sin_addr.s_addr);
+}
+
+static void nsm_display_ipv6_address(const struct sockaddr *sap, char *buf,
+ const size_t len)
+{
+ 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);
+}
+
+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;
+ }
+}
+
+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,
+ };
+
+ 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 = {
- .addr = nsm_addr_in(nsm)->sin_addr.s_addr,
+ .priv = &nsm->sm_priv,
.prog = NLM_PROGRAM,
.vers = 3,
.proc = NLMPROC_NSM_NOTIFY,
}
}
+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 (nlm_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 = XPRT_TRANSPORT_UDP,
- .address = (struct sockaddr *)&sin,
- .addrsize = sizeof(sin),
- .servername = "localhost",
- .program = &nsm_program,
- .version = NSM_VERSION,
- .authflavor = RPC_AUTH_NULL,
- };
+ u64 *p = (u64 *)&nsm->sm_priv.data;
+ struct timespec ts;
- return rpc_create(&args);
+ ktime_get_ts(&ts);
+ *p++ = timespec_to_ns(&ts);
+ *p = (unsigned long)nsm;
+}
+
+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);
+ nsm_display_address((const struct sockaddr *)&new->sm_addr,
+ new->sm_addrbuf, sizeof(new->sm_addrbuf));
+ memcpy(new->sm_name, hostname, hostname_len);
+ new->sm_name[hostname_len] = '\0';
+
+ return new;
+}
+
+/**
+ * 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);
+
+ 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)
+{
+ 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);
+
+ /*
+ * During subsequent lock activity, force a fresh
+ * notification to be set up for this host.
+ */
+ 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);
+ }
}
/*
* The "priv" argument may contain private information required
* by the NSMPROC_MON call. This information will be supplied in the
* NLMPROC_SM_NOTIFY call.
- *
- * Linux provides the raw IP address of the monitored host,
- * left in network byte order.
*/
static int encode_priv(struct xdr_stream *xdr, const struct nsm_args *argp)
{
p = xdr_reserve_space(xdr, SM_PRIV_SIZE);
if (unlikely(p == NULL))
return -EIO;
- *p++ = argp->addr;
- *p++ = 0;
- *p++ = 0;
- *p++ = 0;
+ xdr_encode_opaque_fixed(p, argp->priv->data, SM_PRIV_SIZE);
return 0;
}
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff