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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /net/sunrpc/rpcb_clnt.c
Initial import
Diffstat (limited to 'net/sunrpc/rpcb_clnt.c')
-rw-r--r--net/sunrpc/rpcb_clnt.c1151
1 files changed, 1151 insertions, 0 deletions
diff --git a/net/sunrpc/rpcb_clnt.c b/net/sunrpc/rpcb_clnt.c
new file mode 100644
index 000000000..cf5770d8f
--- /dev/null
+++ b/net/sunrpc/rpcb_clnt.c
@@ -0,0 +1,1151 @@
+/*
+ * In-kernel rpcbind client supporting versions 2, 3, and 4 of the rpcbind
+ * protocol
+ *
+ * Based on RFC 1833: "Binding Protocols for ONC RPC Version 2" and
+ * RFC 3530: "Network File System (NFS) version 4 Protocol"
+ *
+ * Original: Gilles Quillard, Bull Open Source, 2005 <gilles.quillard@bull.net>
+ * Updated: Chuck Lever, Oracle Corporation, 2007 <chuck.lever@oracle.com>
+ *
+ * Descended from net/sunrpc/pmap_clnt.c,
+ * Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de>
+ */
+
+#include <linux/module.h>
+
+#include <linux/types.h>
+#include <linux/socket.h>
+#include <linux/un.h>
+#include <linux/in.h>
+#include <linux/in6.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/mutex.h>
+#include <linux/slab.h>
+#include <net/ipv6.h>
+
+#include <linux/sunrpc/clnt.h>
+#include <linux/sunrpc/addr.h>
+#include <linux/sunrpc/sched.h>
+#include <linux/sunrpc/xprtsock.h>
+
+#include "netns.h"
+
+#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
+# define RPCDBG_FACILITY RPCDBG_BIND
+#endif
+
+#define RPCBIND_SOCK_PATHNAME "/var/run/rpcbind.sock"
+
+#define RPCBIND_PROGRAM (100000u)
+#define RPCBIND_PORT (111u)
+
+#define RPCBVERS_2 (2u)
+#define RPCBVERS_3 (3u)
+#define RPCBVERS_4 (4u)
+
+enum {
+ RPCBPROC_NULL,
+ RPCBPROC_SET,
+ RPCBPROC_UNSET,
+ RPCBPROC_GETPORT,
+ RPCBPROC_GETADDR = 3, /* alias for GETPORT */
+ RPCBPROC_DUMP,
+ RPCBPROC_CALLIT,
+ RPCBPROC_BCAST = 5, /* alias for CALLIT */
+ RPCBPROC_GETTIME,
+ RPCBPROC_UADDR2TADDR,
+ RPCBPROC_TADDR2UADDR,
+ RPCBPROC_GETVERSADDR,
+ RPCBPROC_INDIRECT,
+ RPCBPROC_GETADDRLIST,
+ RPCBPROC_GETSTAT,
+};
+
+/*
+ * r_owner
+ *
+ * The "owner" is allowed to unset a service in the rpcbind database.
+ *
+ * For AF_LOCAL SET/UNSET requests, rpcbind treats this string as a
+ * UID which it maps to a local user name via a password lookup.
+ * In all other cases it is ignored.
+ *
+ * For SET/UNSET requests, user space provides a value, even for
+ * network requests, and GETADDR uses an empty string. We follow
+ * those precedents here.
+ */
+#define RPCB_OWNER_STRING "0"
+#define RPCB_MAXOWNERLEN sizeof(RPCB_OWNER_STRING)
+
+/*
+ * XDR data type sizes
+ */
+#define RPCB_program_sz (1)
+#define RPCB_version_sz (1)
+#define RPCB_protocol_sz (1)
+#define RPCB_port_sz (1)
+#define RPCB_boolean_sz (1)
+
+#define RPCB_netid_sz (1 + XDR_QUADLEN(RPCBIND_MAXNETIDLEN))
+#define RPCB_addr_sz (1 + XDR_QUADLEN(RPCBIND_MAXUADDRLEN))
+#define RPCB_ownerstring_sz (1 + XDR_QUADLEN(RPCB_MAXOWNERLEN))
+
+/*
+ * XDR argument and result sizes
+ */
+#define RPCB_mappingargs_sz (RPCB_program_sz + RPCB_version_sz + \
+ RPCB_protocol_sz + RPCB_port_sz)
+#define RPCB_getaddrargs_sz (RPCB_program_sz + RPCB_version_sz + \
+ RPCB_netid_sz + RPCB_addr_sz + \
+ RPCB_ownerstring_sz)
+
+#define RPCB_getportres_sz RPCB_port_sz
+#define RPCB_setres_sz RPCB_boolean_sz
+
+/*
+ * Note that RFC 1833 does not put any size restrictions on the
+ * address string returned by the remote rpcbind database.
+ */
+#define RPCB_getaddrres_sz RPCB_addr_sz
+
+static void rpcb_getport_done(struct rpc_task *, void *);
+static void rpcb_map_release(void *data);
+static const struct rpc_program rpcb_program;
+
+struct rpcbind_args {
+ struct rpc_xprt * r_xprt;
+
+ u32 r_prog;
+ u32 r_vers;
+ u32 r_prot;
+ unsigned short r_port;
+ const char * r_netid;
+ const char * r_addr;
+ const char * r_owner;
+
+ int r_status;
+};
+
+static struct rpc_procinfo rpcb_procedures2[];
+static struct rpc_procinfo rpcb_procedures3[];
+static struct rpc_procinfo rpcb_procedures4[];
+
+struct rpcb_info {
+ u32 rpc_vers;
+ struct rpc_procinfo * rpc_proc;
+};
+
+static const struct rpcb_info rpcb_next_version[];
+static const struct rpcb_info rpcb_next_version6[];
+
+static const struct rpc_call_ops rpcb_getport_ops = {
+ .rpc_call_done = rpcb_getport_done,
+ .rpc_release = rpcb_map_release,
+};
+
+static void rpcb_wake_rpcbind_waiters(struct rpc_xprt *xprt, int status)
+{
+ xprt_clear_binding(xprt);
+ rpc_wake_up_status(&xprt->binding, status);
+}
+
+static void rpcb_map_release(void *data)
+{
+ struct rpcbind_args *map = data;
+
+ rpcb_wake_rpcbind_waiters(map->r_xprt, map->r_status);
+ xprt_put(map->r_xprt);
+ kfree(map->r_addr);
+ kfree(map);
+}
+
+static int rpcb_get_local(struct net *net)
+{
+ int cnt;
+ struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
+
+ spin_lock(&sn->rpcb_clnt_lock);
+ if (sn->rpcb_users)
+ sn->rpcb_users++;
+ cnt = sn->rpcb_users;
+ spin_unlock(&sn->rpcb_clnt_lock);
+
+ return cnt;
+}
+
+void rpcb_put_local(struct net *net)
+{
+ struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
+ struct rpc_clnt *clnt = sn->rpcb_local_clnt;
+ struct rpc_clnt *clnt4 = sn->rpcb_local_clnt4;
+ int shutdown = 0;
+
+ spin_lock(&sn->rpcb_clnt_lock);
+ if (sn->rpcb_users) {
+ if (--sn->rpcb_users == 0) {
+ sn->rpcb_local_clnt = NULL;
+ sn->rpcb_local_clnt4 = NULL;
+ }
+ shutdown = !sn->rpcb_users;
+ }
+ spin_unlock(&sn->rpcb_clnt_lock);
+
+ if (shutdown) {
+ /*
+ * cleanup_rpcb_clnt - remove xprtsock's sysctls, unregister
+ */
+ if (clnt4)
+ rpc_shutdown_client(clnt4);
+ if (clnt)
+ rpc_shutdown_client(clnt);
+ }
+}
+
+static void rpcb_set_local(struct net *net, struct rpc_clnt *clnt,
+ struct rpc_clnt *clnt4,
+ bool is_af_local)
+{
+ struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
+
+ /* Protected by rpcb_create_local_mutex */
+ sn->rpcb_local_clnt = clnt;
+ sn->rpcb_local_clnt4 = clnt4;
+ sn->rpcb_is_af_local = is_af_local ? 1 : 0;
+ smp_wmb();
+ sn->rpcb_users = 1;
+ dprintk("RPC: created new rpcb local clients (rpcb_local_clnt: "
+ "%p, rpcb_local_clnt4: %p) for net %p%s\n",
+ sn->rpcb_local_clnt, sn->rpcb_local_clnt4,
+ net, (net == &init_net) ? " (init_net)" : "");
+}
+
+/*
+ * Returns zero on success, otherwise a negative errno value
+ * is returned.
+ */
+static int rpcb_create_local_unix(struct net *net)
+{
+ static const struct sockaddr_un rpcb_localaddr_rpcbind = {
+ .sun_family = AF_LOCAL,
+ .sun_path = RPCBIND_SOCK_PATHNAME,
+ };
+ struct rpc_create_args args = {
+ .net = net,
+ .protocol = XPRT_TRANSPORT_LOCAL,
+ .address = (struct sockaddr *)&rpcb_localaddr_rpcbind,
+ .addrsize = sizeof(rpcb_localaddr_rpcbind),
+ .servername = "localhost",
+ .program = &rpcb_program,
+ .version = RPCBVERS_2,
+ .authflavor = RPC_AUTH_NULL,
+ /*
+ * We turn off the idle timeout to prevent the kernel
+ * from automatically disconnecting the socket.
+ * Otherwise, we'd have to cache the mount namespace
+ * of the caller and somehow pass that to the socket
+ * reconnect code.
+ */
+ .flags = RPC_CLNT_CREATE_NO_IDLE_TIMEOUT,
+ };
+ struct rpc_clnt *clnt, *clnt4;
+ int result = 0;
+
+ /*
+ * Because we requested an RPC PING at transport creation time,
+ * this works only if the user space portmapper is rpcbind, and
+ * it's listening on AF_LOCAL on the named socket.
+ */
+ clnt = rpc_create(&args);
+ if (IS_ERR(clnt)) {
+ dprintk("RPC: failed to create AF_LOCAL rpcbind "
+ "client (errno %ld).\n", PTR_ERR(clnt));
+ result = PTR_ERR(clnt);
+ goto out;
+ }
+
+ clnt4 = rpc_bind_new_program(clnt, &rpcb_program, RPCBVERS_4);
+ if (IS_ERR(clnt4)) {
+ dprintk("RPC: failed to bind second program to "
+ "rpcbind v4 client (errno %ld).\n",
+ PTR_ERR(clnt4));
+ clnt4 = NULL;
+ }
+
+ rpcb_set_local(net, clnt, clnt4, true);
+
+out:
+ return result;
+}
+
+/*
+ * Returns zero on success, otherwise a negative errno value
+ * is returned.
+ */
+static int rpcb_create_local_net(struct net *net)
+{
+ static const struct sockaddr_in rpcb_inaddr_loopback = {
+ .sin_family = AF_INET,
+ .sin_addr.s_addr = htonl(INADDR_LOOPBACK),
+ .sin_port = htons(RPCBIND_PORT),
+ };
+ struct rpc_create_args args = {
+ .net = net,
+ .protocol = XPRT_TRANSPORT_TCP,
+ .address = (struct sockaddr *)&rpcb_inaddr_loopback,
+ .addrsize = sizeof(rpcb_inaddr_loopback),
+ .servername = "localhost",
+ .program = &rpcb_program,
+ .version = RPCBVERS_2,
+ .authflavor = RPC_AUTH_UNIX,
+ .flags = RPC_CLNT_CREATE_NOPING,
+ };
+ struct rpc_clnt *clnt, *clnt4;
+ int result = 0;
+
+ clnt = rpc_create(&args);
+ if (IS_ERR(clnt)) {
+ dprintk("RPC: failed to create local rpcbind "
+ "client (errno %ld).\n", PTR_ERR(clnt));
+ result = PTR_ERR(clnt);
+ goto out;
+ }
+
+ /*
+ * This results in an RPC ping. On systems running portmapper,
+ * the v4 ping will fail. Proceed anyway, but disallow rpcb
+ * v4 upcalls.
+ */
+ clnt4 = rpc_bind_new_program(clnt, &rpcb_program, RPCBVERS_4);
+ if (IS_ERR(clnt4)) {
+ dprintk("RPC: failed to bind second program to "
+ "rpcbind v4 client (errno %ld).\n",
+ PTR_ERR(clnt4));
+ clnt4 = NULL;
+ }
+
+ rpcb_set_local(net, clnt, clnt4, false);
+
+out:
+ return result;
+}
+
+/*
+ * Returns zero on success, otherwise a negative errno value
+ * is returned.
+ */
+int rpcb_create_local(struct net *net)
+{
+ static DEFINE_MUTEX(rpcb_create_local_mutex);
+ int result = 0;
+
+ if (rpcb_get_local(net))
+ return result;
+
+ mutex_lock(&rpcb_create_local_mutex);
+ if (rpcb_get_local(net))
+ goto out;
+
+ if (rpcb_create_local_unix(net) != 0)
+ result = rpcb_create_local_net(net);
+
+out:
+ mutex_unlock(&rpcb_create_local_mutex);
+ return result;
+}
+
+static struct rpc_clnt *rpcb_create(struct net *net, const char *nodename,
+ const char *hostname,
+ struct sockaddr *srvaddr, size_t salen,
+ int proto, u32 version)
+{
+ struct rpc_create_args args = {
+ .net = net,
+ .protocol = proto,
+ .address = srvaddr,
+ .addrsize = salen,
+ .servername = hostname,
+ .nodename = nodename,
+ .program = &rpcb_program,
+ .version = version,
+ .authflavor = RPC_AUTH_UNIX,
+ .flags = (RPC_CLNT_CREATE_NOPING |
+ RPC_CLNT_CREATE_NONPRIVPORT),
+ };
+
+ switch (srvaddr->sa_family) {
+ case AF_INET:
+ ((struct sockaddr_in *)srvaddr)->sin_port = htons(RPCBIND_PORT);
+ break;
+ case AF_INET6:
+ ((struct sockaddr_in6 *)srvaddr)->sin6_port = htons(RPCBIND_PORT);
+ break;
+ default:
+ return ERR_PTR(-EAFNOSUPPORT);
+ }
+
+ return rpc_create(&args);
+}
+
+static int rpcb_register_call(struct sunrpc_net *sn, struct rpc_clnt *clnt, struct rpc_message *msg, bool is_set)
+{
+ int flags = RPC_TASK_NOCONNECT;
+ int error, result = 0;
+
+ if (is_set || !sn->rpcb_is_af_local)
+ flags = RPC_TASK_SOFTCONN;
+ msg->rpc_resp = &result;
+
+ error = rpc_call_sync(clnt, msg, flags);
+ if (error < 0) {
+ dprintk("RPC: failed to contact local rpcbind "
+ "server (errno %d).\n", -error);
+ return error;
+ }
+
+ if (!result)
+ return -EACCES;
+ return 0;
+}
+
+/**
+ * rpcb_register - set or unset a port registration with the local rpcbind svc
+ * @net: target network namespace
+ * @prog: RPC program number to bind
+ * @vers: RPC version number to bind
+ * @prot: transport protocol to register
+ * @port: port value to register
+ *
+ * Returns zero if the registration request was dispatched successfully
+ * and the rpcbind daemon returned success. Otherwise, returns an errno
+ * value that reflects the nature of the error (request could not be
+ * dispatched, timed out, or rpcbind returned an error).
+ *
+ * RPC services invoke this function to advertise their contact
+ * information via the system's rpcbind daemon. RPC services
+ * invoke this function once for each [program, version, transport]
+ * tuple they wish to advertise.
+ *
+ * Callers may also unregister RPC services that are no longer
+ * available by setting the passed-in port to zero. This removes
+ * all registered transports for [program, version] from the local
+ * rpcbind database.
+ *
+ * This function uses rpcbind protocol version 2 to contact the
+ * local rpcbind daemon.
+ *
+ * Registration works over both AF_INET and AF_INET6, and services
+ * registered via this function are advertised as available for any
+ * address. If the local rpcbind daemon is listening on AF_INET6,
+ * services registered via this function will be advertised on
+ * IN6ADDR_ANY (ie available for all AF_INET and AF_INET6
+ * addresses).
+ */
+int rpcb_register(struct net *net, u32 prog, u32 vers, int prot, unsigned short port)
+{
+ struct rpcbind_args map = {
+ .r_prog = prog,
+ .r_vers = vers,
+ .r_prot = prot,
+ .r_port = port,
+ };
+ struct rpc_message msg = {
+ .rpc_argp = &map,
+ };
+ struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
+ bool is_set = false;
+
+ dprintk("RPC: %sregistering (%u, %u, %d, %u) with local "
+ "rpcbind\n", (port ? "" : "un"),
+ prog, vers, prot, port);
+
+ msg.rpc_proc = &rpcb_procedures2[RPCBPROC_UNSET];
+ if (port != 0) {
+ msg.rpc_proc = &rpcb_procedures2[RPCBPROC_SET];
+ is_set = true;
+ }
+
+ return rpcb_register_call(sn, sn->rpcb_local_clnt, &msg, is_set);
+}
+
+/*
+ * Fill in AF_INET family-specific arguments to register
+ */
+static int rpcb_register_inet4(struct sunrpc_net *sn,
+ const struct sockaddr *sap,
+ struct rpc_message *msg)
+{
+ const struct sockaddr_in *sin = (const struct sockaddr_in *)sap;
+ struct rpcbind_args *map = msg->rpc_argp;
+ unsigned short port = ntohs(sin->sin_port);
+ bool is_set = false;
+ int result;
+
+ map->r_addr = rpc_sockaddr2uaddr(sap, GFP_KERNEL);
+
+ dprintk("RPC: %sregistering [%u, %u, %s, '%s'] with "
+ "local rpcbind\n", (port ? "" : "un"),
+ map->r_prog, map->r_vers,
+ map->r_addr, map->r_netid);
+
+ msg->rpc_proc = &rpcb_procedures4[RPCBPROC_UNSET];
+ if (port != 0) {
+ msg->rpc_proc = &rpcb_procedures4[RPCBPROC_SET];
+ is_set = true;
+ }
+
+ result = rpcb_register_call(sn, sn->rpcb_local_clnt4, msg, is_set);
+ kfree(map->r_addr);
+ return result;
+}
+
+/*
+ * Fill in AF_INET6 family-specific arguments to register
+ */
+static int rpcb_register_inet6(struct sunrpc_net *sn,
+ const struct sockaddr *sap,
+ struct rpc_message *msg)
+{
+ const struct sockaddr_in6 *sin6 = (const struct sockaddr_in6 *)sap;
+ struct rpcbind_args *map = msg->rpc_argp;
+ unsigned short port = ntohs(sin6->sin6_port);
+ bool is_set = false;
+ int result;
+
+ map->r_addr = rpc_sockaddr2uaddr(sap, GFP_KERNEL);
+
+ dprintk("RPC: %sregistering [%u, %u, %s, '%s'] with "
+ "local rpcbind\n", (port ? "" : "un"),
+ map->r_prog, map->r_vers,
+ map->r_addr, map->r_netid);
+
+ msg->rpc_proc = &rpcb_procedures4[RPCBPROC_UNSET];
+ if (port != 0) {
+ msg->rpc_proc = &rpcb_procedures4[RPCBPROC_SET];
+ is_set = true;
+ }
+
+ result = rpcb_register_call(sn, sn->rpcb_local_clnt4, msg, is_set);
+ kfree(map->r_addr);
+ return result;
+}
+
+static int rpcb_unregister_all_protofamilies(struct sunrpc_net *sn,
+ struct rpc_message *msg)
+{
+ struct rpcbind_args *map = msg->rpc_argp;
+
+ dprintk("RPC: unregistering [%u, %u, '%s'] with "
+ "local rpcbind\n",
+ map->r_prog, map->r_vers, map->r_netid);
+
+ map->r_addr = "";
+ msg->rpc_proc = &rpcb_procedures4[RPCBPROC_UNSET];
+
+ return rpcb_register_call(sn, sn->rpcb_local_clnt4, msg, false);
+}
+
+/**
+ * rpcb_v4_register - set or unset a port registration with the local rpcbind
+ * @net: target network namespace
+ * @program: RPC program number of service to (un)register
+ * @version: RPC version number of service to (un)register
+ * @address: address family, IP address, and port to (un)register
+ * @netid: netid of transport protocol to (un)register
+ *
+ * Returns zero if the registration request was dispatched successfully
+ * and the rpcbind daemon returned success. Otherwise, returns an errno
+ * value that reflects the nature of the error (request could not be
+ * dispatched, timed out, or rpcbind returned an error).
+ *
+ * RPC services invoke this function to advertise their contact
+ * information via the system's rpcbind daemon. RPC services
+ * invoke this function once for each [program, version, address,
+ * netid] tuple they wish to advertise.
+ *
+ * Callers may also unregister RPC services that are registered at a
+ * specific address by setting the port number in @address to zero.
+ * They may unregister all registered protocol families at once for
+ * a service by passing a NULL @address argument. If @netid is ""
+ * then all netids for [program, version, address] are unregistered.
+ *
+ * This function uses rpcbind protocol version 4 to contact the
+ * local rpcbind daemon. The local rpcbind daemon must support
+ * version 4 of the rpcbind protocol in order for these functions
+ * to register a service successfully.
+ *
+ * Supported netids include "udp" and "tcp" for UDP and TCP over
+ * IPv4, and "udp6" and "tcp6" for UDP and TCP over IPv6,
+ * respectively.
+ *
+ * The contents of @address determine the address family and the
+ * port to be registered. The usual practice is to pass INADDR_ANY
+ * as the raw address, but specifying a non-zero address is also
+ * supported by this API if the caller wishes to advertise an RPC
+ * service on a specific network interface.
+ *
+ * Note that passing in INADDR_ANY does not create the same service
+ * registration as IN6ADDR_ANY. The former advertises an RPC
+ * service on any IPv4 address, but not on IPv6. The latter
+ * advertises the service on all IPv4 and IPv6 addresses.
+ */
+int rpcb_v4_register(struct net *net, const u32 program, const u32 version,
+ const struct sockaddr *address, const char *netid)
+{
+ struct rpcbind_args map = {
+ .r_prog = program,
+ .r_vers = version,
+ .r_netid = netid,
+ .r_owner = RPCB_OWNER_STRING,
+ };
+ struct rpc_message msg = {
+ .rpc_argp = &map,
+ };
+ struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
+
+ if (sn->rpcb_local_clnt4 == NULL)
+ return -EPROTONOSUPPORT;
+
+ if (address == NULL)
+ return rpcb_unregister_all_protofamilies(sn, &msg);
+
+ switch (address->sa_family) {
+ case AF_INET:
+ return rpcb_register_inet4(sn, address, &msg);
+ case AF_INET6:
+ return rpcb_register_inet6(sn, address, &msg);
+ }
+
+ return -EAFNOSUPPORT;
+}
+
+static struct rpc_task *rpcb_call_async(struct rpc_clnt *rpcb_clnt, struct rpcbind_args *map, struct rpc_procinfo *proc)
+{
+ struct rpc_message msg = {
+ .rpc_proc = proc,
+ .rpc_argp = map,
+ .rpc_resp = map,
+ };
+ struct rpc_task_setup task_setup_data = {
+ .rpc_client = rpcb_clnt,
+ .rpc_message = &msg,
+ .callback_ops = &rpcb_getport_ops,
+ .callback_data = map,
+ .flags = RPC_TASK_ASYNC | RPC_TASK_SOFTCONN,
+ };
+
+ return rpc_run_task(&task_setup_data);
+}
+
+/*
+ * In the case where rpc clients have been cloned, we want to make
+ * sure that we use the program number/version etc of the actual
+ * owner of the xprt. To do so, we walk back up the tree of parents
+ * to find whoever created the transport and/or whoever has the
+ * autobind flag set.
+ */
+static struct rpc_clnt *rpcb_find_transport_owner(struct rpc_clnt *clnt)
+{
+ struct rpc_clnt *parent = clnt->cl_parent;
+ struct rpc_xprt *xprt = rcu_dereference(clnt->cl_xprt);
+
+ while (parent != clnt) {
+ if (rcu_dereference(parent->cl_xprt) != xprt)
+ break;
+ if (clnt->cl_autobind)
+ break;
+ clnt = parent;
+ parent = parent->cl_parent;
+ }
+ return clnt;
+}
+
+/**
+ * rpcb_getport_async - obtain the port for a given RPC service on a given host
+ * @task: task that is waiting for portmapper request
+ *
+ * This one can be called for an ongoing RPC request, and can be used in
+ * an async (rpciod) context.
+ */
+void rpcb_getport_async(struct rpc_task *task)
+{
+ struct rpc_clnt *clnt;
+ struct rpc_procinfo *proc;
+ u32 bind_version;
+ struct rpc_xprt *xprt;
+ struct rpc_clnt *rpcb_clnt;
+ struct rpcbind_args *map;
+ struct rpc_task *child;
+ struct sockaddr_storage addr;
+ struct sockaddr *sap = (struct sockaddr *)&addr;
+ size_t salen;
+ int status;
+
+ rcu_read_lock();
+ do {
+ clnt = rpcb_find_transport_owner(task->tk_client);
+ xprt = xprt_get(rcu_dereference(clnt->cl_xprt));
+ } while (xprt == NULL);
+ rcu_read_unlock();
+
+ dprintk("RPC: %5u %s(%s, %u, %u, %d)\n",
+ task->tk_pid, __func__,
+ xprt->servername, clnt->cl_prog, clnt->cl_vers, xprt->prot);
+
+ /* Put self on the wait queue to ensure we get notified if
+ * some other task is already attempting to bind the port */
+ rpc_sleep_on(&xprt->binding, task, NULL);
+
+ if (xprt_test_and_set_binding(xprt)) {
+ dprintk("RPC: %5u %s: waiting for another binder\n",
+ task->tk_pid, __func__);
+ xprt_put(xprt);
+ return;
+ }
+
+ /* Someone else may have bound if we slept */
+ if (xprt_bound(xprt)) {
+ status = 0;
+ dprintk("RPC: %5u %s: already bound\n",
+ task->tk_pid, __func__);
+ goto bailout_nofree;
+ }
+
+ /* Parent transport's destination address */
+ salen = rpc_peeraddr(clnt, sap, sizeof(addr));
+
+ /* Don't ever use rpcbind v2 for AF_INET6 requests */
+ switch (sap->sa_family) {
+ case AF_INET:
+ proc = rpcb_next_version[xprt->bind_index].rpc_proc;
+ bind_version = rpcb_next_version[xprt->bind_index].rpc_vers;
+ break;
+ case AF_INET6:
+ proc = rpcb_next_version6[xprt->bind_index].rpc_proc;
+ bind_version = rpcb_next_version6[xprt->bind_index].rpc_vers;
+ break;
+ default:
+ status = -EAFNOSUPPORT;
+ dprintk("RPC: %5u %s: bad address family\n",
+ task->tk_pid, __func__);
+ goto bailout_nofree;
+ }
+ if (proc == NULL) {
+ xprt->bind_index = 0;
+ status = -EPFNOSUPPORT;
+ dprintk("RPC: %5u %s: no more getport versions available\n",
+ task->tk_pid, __func__);
+ goto bailout_nofree;
+ }
+
+ dprintk("RPC: %5u %s: trying rpcbind version %u\n",
+ task->tk_pid, __func__, bind_version);
+
+ rpcb_clnt = rpcb_create(xprt->xprt_net,
+ clnt->cl_nodename,
+ xprt->servername, sap, salen,
+ xprt->prot, bind_version);
+ if (IS_ERR(rpcb_clnt)) {
+ status = PTR_ERR(rpcb_clnt);
+ dprintk("RPC: %5u %s: rpcb_create failed, error %ld\n",
+ task->tk_pid, __func__, PTR_ERR(rpcb_clnt));
+ goto bailout_nofree;
+ }
+
+ map = kzalloc(sizeof(struct rpcbind_args), GFP_ATOMIC);
+ if (!map) {
+ status = -ENOMEM;
+ dprintk("RPC: %5u %s: no memory available\n",
+ task->tk_pid, __func__);
+ goto bailout_release_client;
+ }
+ map->r_prog = clnt->cl_prog;
+ map->r_vers = clnt->cl_vers;
+ map->r_prot = xprt->prot;
+ map->r_port = 0;
+ map->r_xprt = xprt;
+ map->r_status = -EIO;
+
+ switch (bind_version) {
+ case RPCBVERS_4:
+ case RPCBVERS_3:
+ map->r_netid = xprt->address_strings[RPC_DISPLAY_NETID];
+ map->r_addr = rpc_sockaddr2uaddr(sap, GFP_ATOMIC);
+ map->r_owner = "";
+ break;
+ case RPCBVERS_2:
+ map->r_addr = NULL;
+ break;
+ default:
+ BUG();
+ }
+
+ child = rpcb_call_async(rpcb_clnt, map, proc);
+ rpc_release_client(rpcb_clnt);
+ if (IS_ERR(child)) {
+ /* rpcb_map_release() has freed the arguments */
+ dprintk("RPC: %5u %s: rpc_run_task failed\n",
+ task->tk_pid, __func__);
+ return;
+ }
+
+ xprt->stat.bind_count++;
+ rpc_put_task(child);
+ return;
+
+bailout_release_client:
+ rpc_release_client(rpcb_clnt);
+bailout_nofree:
+ rpcb_wake_rpcbind_waiters(xprt, status);
+ task->tk_status = status;
+ xprt_put(xprt);
+}
+EXPORT_SYMBOL_GPL(rpcb_getport_async);
+
+/*
+ * Rpcbind child task calls this callback via tk_exit.
+ */
+static void rpcb_getport_done(struct rpc_task *child, void *data)
+{
+ struct rpcbind_args *map = data;
+ struct rpc_xprt *xprt = map->r_xprt;
+ int status = child->tk_status;
+
+ /* Garbage reply: retry with a lesser rpcbind version */
+ if (status == -EIO)
+ status = -EPROTONOSUPPORT;
+
+ /* rpcbind server doesn't support this rpcbind protocol version */
+ if (status == -EPROTONOSUPPORT)
+ xprt->bind_index++;
+
+ if (status < 0) {
+ /* rpcbind server not available on remote host? */
+ xprt->ops->set_port(xprt, 0);
+ } else if (map->r_port == 0) {
+ /* Requested RPC service wasn't registered on remote host */
+ xprt->ops->set_port(xprt, 0);
+ status = -EACCES;
+ } else {
+ /* Succeeded */
+ xprt->ops->set_port(xprt, map->r_port);
+ xprt_set_bound(xprt);
+ status = 0;
+ }
+
+ dprintk("RPC: %5u rpcb_getport_done(status %d, port %u)\n",
+ child->tk_pid, status, map->r_port);
+
+ map->r_status = status;
+}
+
+/*
+ * XDR functions for rpcbind
+ */
+
+static void rpcb_enc_mapping(struct rpc_rqst *req, struct xdr_stream *xdr,
+ const struct rpcbind_args *rpcb)
+{
+ __be32 *p;
+
+ dprintk("RPC: %5u encoding PMAP_%s call (%u, %u, %d, %u)\n",
+ req->rq_task->tk_pid,
+ req->rq_task->tk_msg.rpc_proc->p_name,
+ rpcb->r_prog, rpcb->r_vers, rpcb->r_prot, rpcb->r_port);
+
+ p = xdr_reserve_space(xdr, RPCB_mappingargs_sz << 2);
+ *p++ = cpu_to_be32(rpcb->r_prog);
+ *p++ = cpu_to_be32(rpcb->r_vers);
+ *p++ = cpu_to_be32(rpcb->r_prot);
+ *p = cpu_to_be32(rpcb->r_port);
+}
+
+static int rpcb_dec_getport(struct rpc_rqst *req, struct xdr_stream *xdr,
+ struct rpcbind_args *rpcb)
+{
+ unsigned long port;
+ __be32 *p;
+
+ rpcb->r_port = 0;
+
+ p = xdr_inline_decode(xdr, 4);
+ if (unlikely(p == NULL))
+ return -EIO;
+
+ port = be32_to_cpup(p);
+ dprintk("RPC: %5u PMAP_%s result: %lu\n", req->rq_task->tk_pid,
+ req->rq_task->tk_msg.rpc_proc->p_name, port);
+ if (unlikely(port > USHRT_MAX))
+ return -EIO;
+
+ rpcb->r_port = port;
+ return 0;
+}
+
+static int rpcb_dec_set(struct rpc_rqst *req, struct xdr_stream *xdr,
+ unsigned int *boolp)
+{
+ __be32 *p;
+
+ p = xdr_inline_decode(xdr, 4);
+ if (unlikely(p == NULL))
+ return -EIO;
+
+ *boolp = 0;
+ if (*p != xdr_zero)
+ *boolp = 1;
+
+ dprintk("RPC: %5u RPCB_%s call %s\n",
+ req->rq_task->tk_pid,
+ req->rq_task->tk_msg.rpc_proc->p_name,
+ (*boolp ? "succeeded" : "failed"));
+ return 0;
+}
+
+static void encode_rpcb_string(struct xdr_stream *xdr, const char *string,
+ const u32 maxstrlen)
+{
+ __be32 *p;
+ u32 len;
+
+ len = strlen(string);
+ WARN_ON_ONCE(len > maxstrlen);
+ if (len > maxstrlen)
+ /* truncate and hope for the best */
+ len = maxstrlen;
+ p = xdr_reserve_space(xdr, 4 + len);
+ xdr_encode_opaque(p, string, len);
+}
+
+static void rpcb_enc_getaddr(struct rpc_rqst *req, struct xdr_stream *xdr,
+ const struct rpcbind_args *rpcb)
+{
+ __be32 *p;
+
+ dprintk("RPC: %5u encoding RPCB_%s call (%u, %u, '%s', '%s')\n",
+ req->rq_task->tk_pid,
+ req->rq_task->tk_msg.rpc_proc->p_name,
+ rpcb->r_prog, rpcb->r_vers,
+ rpcb->r_netid, rpcb->r_addr);
+
+ p = xdr_reserve_space(xdr, (RPCB_program_sz + RPCB_version_sz) << 2);
+ *p++ = cpu_to_be32(rpcb->r_prog);
+ *p = cpu_to_be32(rpcb->r_vers);
+
+ encode_rpcb_string(xdr, rpcb->r_netid, RPCBIND_MAXNETIDLEN);
+ encode_rpcb_string(xdr, rpcb->r_addr, RPCBIND_MAXUADDRLEN);
+ encode_rpcb_string(xdr, rpcb->r_owner, RPCB_MAXOWNERLEN);
+}
+
+static int rpcb_dec_getaddr(struct rpc_rqst *req, struct xdr_stream *xdr,
+ struct rpcbind_args *rpcb)
+{
+ struct sockaddr_storage address;
+ struct sockaddr *sap = (struct sockaddr *)&address;
+ __be32 *p;
+ u32 len;
+
+ rpcb->r_port = 0;
+
+ p = xdr_inline_decode(xdr, 4);
+ if (unlikely(p == NULL))
+ goto out_fail;
+ len = be32_to_cpup(p);
+
+ /*
+ * If the returned universal address is a null string,
+ * the requested RPC service was not registered.
+ */
+ if (len == 0) {
+ dprintk("RPC: %5u RPCB reply: program not registered\n",
+ req->rq_task->tk_pid);
+ return 0;
+ }
+
+ if (unlikely(len > RPCBIND_MAXUADDRLEN))
+ goto out_fail;
+
+ p = xdr_inline_decode(xdr, len);
+ if (unlikely(p == NULL))
+ goto out_fail;
+ dprintk("RPC: %5u RPCB_%s reply: %s\n", req->rq_task->tk_pid,
+ req->rq_task->tk_msg.rpc_proc->p_name, (char *)p);
+
+ if (rpc_uaddr2sockaddr(req->rq_xprt->xprt_net, (char *)p, len,
+ sap, sizeof(address)) == 0)
+ goto out_fail;
+ rpcb->r_port = rpc_get_port(sap);
+
+ return 0;
+
+out_fail:
+ dprintk("RPC: %5u malformed RPCB_%s reply\n",
+ req->rq_task->tk_pid,
+ req->rq_task->tk_msg.rpc_proc->p_name);
+ return -EIO;
+}
+
+/*
+ * Not all rpcbind procedures described in RFC 1833 are implemented
+ * since the Linux kernel RPC code requires only these.
+ */
+
+static struct rpc_procinfo rpcb_procedures2[] = {
+ [RPCBPROC_SET] = {
+ .p_proc = RPCBPROC_SET,
+ .p_encode = (kxdreproc_t)rpcb_enc_mapping,
+ .p_decode = (kxdrdproc_t)rpcb_dec_set,
+ .p_arglen = RPCB_mappingargs_sz,
+ .p_replen = RPCB_setres_sz,
+ .p_statidx = RPCBPROC_SET,
+ .p_timer = 0,
+ .p_name = "SET",
+ },
+ [RPCBPROC_UNSET] = {
+ .p_proc = RPCBPROC_UNSET,
+ .p_encode = (kxdreproc_t)rpcb_enc_mapping,
+ .p_decode = (kxdrdproc_t)rpcb_dec_set,
+ .p_arglen = RPCB_mappingargs_sz,
+ .p_replen = RPCB_setres_sz,
+ .p_statidx = RPCBPROC_UNSET,
+ .p_timer = 0,
+ .p_name = "UNSET",
+ },
+ [RPCBPROC_GETPORT] = {
+ .p_proc = RPCBPROC_GETPORT,
+ .p_encode = (kxdreproc_t)rpcb_enc_mapping,
+ .p_decode = (kxdrdproc_t)rpcb_dec_getport,
+ .p_arglen = RPCB_mappingargs_sz,
+ .p_replen = RPCB_getportres_sz,
+ .p_statidx = RPCBPROC_GETPORT,
+ .p_timer = 0,
+ .p_name = "GETPORT",
+ },
+};
+
+static struct rpc_procinfo rpcb_procedures3[] = {
+ [RPCBPROC_SET] = {
+ .p_proc = RPCBPROC_SET,
+ .p_encode = (kxdreproc_t)rpcb_enc_getaddr,
+ .p_decode = (kxdrdproc_t)rpcb_dec_set,
+ .p_arglen = RPCB_getaddrargs_sz,
+ .p_replen = RPCB_setres_sz,
+ .p_statidx = RPCBPROC_SET,
+ .p_timer = 0,
+ .p_name = "SET",
+ },
+ [RPCBPROC_UNSET] = {
+ .p_proc = RPCBPROC_UNSET,
+ .p_encode = (kxdreproc_t)rpcb_enc_getaddr,
+ .p_decode = (kxdrdproc_t)rpcb_dec_set,
+ .p_arglen = RPCB_getaddrargs_sz,
+ .p_replen = RPCB_setres_sz,
+ .p_statidx = RPCBPROC_UNSET,
+ .p_timer = 0,
+ .p_name = "UNSET",
+ },
+ [RPCBPROC_GETADDR] = {
+ .p_proc = RPCBPROC_GETADDR,
+ .p_encode = (kxdreproc_t)rpcb_enc_getaddr,
+ .p_decode = (kxdrdproc_t)rpcb_dec_getaddr,
+ .p_arglen = RPCB_getaddrargs_sz,
+ .p_replen = RPCB_getaddrres_sz,
+ .p_statidx = RPCBPROC_GETADDR,
+ .p_timer = 0,
+ .p_name = "GETADDR",
+ },
+};
+
+static struct rpc_procinfo rpcb_procedures4[] = {
+ [RPCBPROC_SET] = {
+ .p_proc = RPCBPROC_SET,
+ .p_encode = (kxdreproc_t)rpcb_enc_getaddr,
+ .p_decode = (kxdrdproc_t)rpcb_dec_set,
+ .p_arglen = RPCB_getaddrargs_sz,
+ .p_replen = RPCB_setres_sz,
+ .p_statidx = RPCBPROC_SET,
+ .p_timer = 0,
+ .p_name = "SET",
+ },
+ [RPCBPROC_UNSET] = {
+ .p_proc = RPCBPROC_UNSET,
+ .p_encode = (kxdreproc_t)rpcb_enc_getaddr,
+ .p_decode = (kxdrdproc_t)rpcb_dec_set,
+ .p_arglen = RPCB_getaddrargs_sz,
+ .p_replen = RPCB_setres_sz,
+ .p_statidx = RPCBPROC_UNSET,
+ .p_timer = 0,
+ .p_name = "UNSET",
+ },
+ [RPCBPROC_GETADDR] = {
+ .p_proc = RPCBPROC_GETADDR,
+ .p_encode = (kxdreproc_t)rpcb_enc_getaddr,
+ .p_decode = (kxdrdproc_t)rpcb_dec_getaddr,
+ .p_arglen = RPCB_getaddrargs_sz,
+ .p_replen = RPCB_getaddrres_sz,
+ .p_statidx = RPCBPROC_GETADDR,
+ .p_timer = 0,
+ .p_name = "GETADDR",
+ },
+};
+
+static const struct rpcb_info rpcb_next_version[] = {
+ {
+ .rpc_vers = RPCBVERS_2,
+ .rpc_proc = &rpcb_procedures2[RPCBPROC_GETPORT],
+ },
+ {
+ .rpc_proc = NULL,
+ },
+};
+
+static const struct rpcb_info rpcb_next_version6[] = {
+ {
+ .rpc_vers = RPCBVERS_4,
+ .rpc_proc = &rpcb_procedures4[RPCBPROC_GETADDR],
+ },
+ {
+ .rpc_vers = RPCBVERS_3,
+ .rpc_proc = &rpcb_procedures3[RPCBPROC_GETADDR],
+ },
+ {
+ .rpc_proc = NULL,
+ },
+};
+
+static const struct rpc_version rpcb_version2 = {
+ .number = RPCBVERS_2,
+ .nrprocs = ARRAY_SIZE(rpcb_procedures2),
+ .procs = rpcb_procedures2
+};
+
+static const struct rpc_version rpcb_version3 = {
+ .number = RPCBVERS_3,
+ .nrprocs = ARRAY_SIZE(rpcb_procedures3),
+ .procs = rpcb_procedures3
+};
+
+static const struct rpc_version rpcb_version4 = {
+ .number = RPCBVERS_4,
+ .nrprocs = ARRAY_SIZE(rpcb_procedures4),
+ .procs = rpcb_procedures4
+};
+
+static const struct rpc_version *rpcb_version[] = {
+ NULL,
+ NULL,
+ &rpcb_version2,
+ &rpcb_version3,
+ &rpcb_version4
+};
+
+static struct rpc_stat rpcb_stats;
+
+static const struct rpc_program rpcb_program = {
+ .name = "rpcbind",
+ .number = RPCBIND_PROGRAM,
+ .nrvers = ARRAY_SIZE(rpcb_version),
+ .version = rpcb_version,
+ .stats = &rpcb_stats,
+};