diff options
Diffstat (limited to 'net/sunrpc/rpcb_clnt.c')
| -rw-r--r-- | net/sunrpc/rpcb_clnt.c | 1121 |
1 files changed, 1121 insertions, 0 deletions
diff --git a/net/sunrpc/rpcb_clnt.c b/net/sunrpc/rpcb_clnt.c new file mode 100644 index 000000000..102c3818b --- /dev/null +++ b/net/sunrpc/rpcb_clnt.c @@ -0,0 +1,1121 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * 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 <trace/events/sunrpc.h> + +#include "netns.h" + +#define RPCBIND_SOCK_PATHNAME "/var/run/rpcbind.sock" +#define RPCBIND_SOCK_ABSTRACT_NAME "\0/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 const struct rpc_procinfo rpcb_procedures2[]; +static const struct rpc_procinfo rpcb_procedures3[]; +static const struct rpc_procinfo rpcb_procedures4[]; + +struct rpcb_info { + u32 rpc_vers; + const 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; +} + +/* Evaluate to actual length of the `sockaddr_un' structure. */ +# define SUN_LEN(ptr) (offsetof(struct sockaddr_un, sun_path) \ + + 1 + strlen((ptr)->sun_path + 1)) + +/* + * Returns zero on success, otherwise a negative errno value + * is returned. + */ +static int rpcb_create_af_local(struct net *net, + const struct sockaddr_un *addr) +{ + struct rpc_create_args args = { + .net = net, + .protocol = XPRT_TRANSPORT_LOCAL, + .address = (struct sockaddr *)addr, + .addrsize = SUN_LEN(addr), + .servername = "localhost", + .program = &rpcb_program, + .version = RPCBVERS_2, + .authflavor = RPC_AUTH_NULL, + .cred = current_cred(), + /* + * 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)) { + result = PTR_ERR(clnt); + goto out; + } + + clnt4 = rpc_bind_new_program(clnt, &rpcb_program, RPCBVERS_4); + if (IS_ERR(clnt4)) + clnt4 = NULL; + + rpcb_set_local(net, clnt, clnt4, true); + +out: + return result; +} + +static int rpcb_create_local_abstract(struct net *net) +{ + static const struct sockaddr_un rpcb_localaddr_abstract = { + .sun_family = AF_LOCAL, + .sun_path = RPCBIND_SOCK_ABSTRACT_NAME, + }; + + return rpcb_create_af_local(net, &rpcb_localaddr_abstract); +} + +static int rpcb_create_local_unix(struct net *net) +{ + static const struct sockaddr_un rpcb_localaddr_unix = { + .sun_family = AF_LOCAL, + .sun_path = RPCBIND_SOCK_PATHNAME, + }; + + return rpcb_create_af_local(net, &rpcb_localaddr_unix); +} + +/* + * 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, + .cred = current_cred(), + .flags = RPC_CLNT_CREATE_NOPING, + }; + struct rpc_clnt *clnt, *clnt4; + int result = 0; + + clnt = rpc_create(&args); + if (IS_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)) + 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_abstract(net) != 0 && + 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, + const struct cred *cred, + const struct rpc_timeout *timeo) +{ + struct rpc_create_args args = { + .net = net, + .protocol = proto, + .address = srvaddr, + .addrsize = salen, + .timeout = timeo, + .servername = hostname, + .nodename = nodename, + .program = &rpcb_program, + .version = version, + .authflavor = RPC_AUTH_UNIX, + .cred = cred, + .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) + 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; + + trace_pmap_register(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); + + 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); + + 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; + + trace_rpcb_unregister(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); + + trace_rpcb_register(map.r_prog, map.r_vers, map.r_addr, map.r_netid); + + 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, const 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_switch *xps = rcu_access_pointer(clnt->cl_xpi.xpi_xpswitch); + + while (parent != clnt) { + if (rcu_access_pointer(parent->cl_xpi.xpi_xpswitch) != xps) + 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; + const 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(); + clnt = rpcb_find_transport_owner(task->tk_client); + rcu_read_unlock(); + xprt = xprt_get(task->tk_xprt); + + /* 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_timeout(&xprt->binding, task, + NULL, jiffies + xprt->bind_timeout); + + if (xprt_test_and_set_binding(xprt)) { + xprt_put(xprt); + return; + } + + /* Someone else may have bound if we slept */ + if (xprt_bound(xprt)) { + status = 0; + 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; + goto bailout_nofree; + } + if (proc == NULL) { + xprt->bind_index = 0; + status = -EPFNOSUPPORT; + goto bailout_nofree; + } + + trace_rpcb_getport(clnt, task, bind_version); + + rpcb_clnt = rpcb_create(xprt->xprt_net, + clnt->cl_nodename, + xprt->servername, sap, salen, + xprt->prot, bind_version, + clnt->cl_cred, + task->tk_client->cl_timeout); + if (IS_ERR(rpcb_clnt)) { + status = PTR_ERR(rpcb_clnt); + goto bailout_nofree; + } + + map = kzalloc(sizeof(struct rpcbind_args), rpc_task_gfp_mask()); + if (!map) { + status = -ENOMEM; + 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, rpc_task_gfp_mask()); + if (!map->r_addr) { + status = -ENOMEM; + goto bailout_free_args; + } + 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 */ + return; + } + + xprt->stat.bind_count++; + rpc_put_task(child); + return; + +bailout_free_args: + kfree(map); +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; + + map->r_status = child->tk_status; + + /* Garbage reply: retry with a lesser rpcbind version */ + if (map->r_status == -EIO) + map->r_status = -EPROTONOSUPPORT; + + /* rpcbind server doesn't support this rpcbind protocol version */ + if (map->r_status == -EPROTONOSUPPORT) + xprt->bind_index++; + + if (map->r_status < 0) { + /* rpcbind server not available on remote host? */ + map->r_port = 0; + + } else if (map->r_port == 0) { + /* Requested RPC service wasn't registered on remote host */ + map->r_status = -EACCES; + } else { + /* Succeeded */ + map->r_status = 0; + } + + trace_rpcb_setport(child, map->r_status, map->r_port); + xprt->ops->set_port(xprt, map->r_port); + if (map->r_port) + xprt_set_bound(xprt); +} + +/* + * XDR functions for rpcbind + */ + +static void rpcb_enc_mapping(struct rpc_rqst *req, struct xdr_stream *xdr, + const void *data) +{ + const struct rpcbind_args *rpcb = data; + __be32 *p; + + 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, + void *data) +{ + struct rpcbind_args *rpcb = data; + 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); + 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, + void *data) +{ + unsigned int *boolp = data; + __be32 *p; + + p = xdr_inline_decode(xdr, 4); + if (unlikely(p == NULL)) + return -EIO; + + *boolp = 0; + if (*p != xdr_zero) + *boolp = 1; + 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 void *data) +{ + const struct rpcbind_args *rpcb = data; + __be32 *p; + + 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, + void *data) +{ + struct rpcbind_args *rpcb = data; + 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) + return 0; + + if (unlikely(len > RPCBIND_MAXUADDRLEN)) + goto out_fail; + + p = xdr_inline_decode(xdr, len); + if (unlikely(p == NULL)) + goto out_fail; + + 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: + return -EIO; +} + +/* + * Not all rpcbind procedures described in RFC 1833 are implemented + * since the Linux kernel RPC code requires only these. + */ + +static const struct rpc_procinfo rpcb_procedures2[] = { + [RPCBPROC_SET] = { + .p_proc = RPCBPROC_SET, + .p_encode = rpcb_enc_mapping, + .p_decode = 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 = rpcb_enc_mapping, + .p_decode = 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 = rpcb_enc_mapping, + .p_decode = rpcb_dec_getport, + .p_arglen = RPCB_mappingargs_sz, + .p_replen = RPCB_getportres_sz, + .p_statidx = RPCBPROC_GETPORT, + .p_timer = 0, + .p_name = "GETPORT", + }, +}; + +static const struct rpc_procinfo rpcb_procedures3[] = { + [RPCBPROC_SET] = { + .p_proc = RPCBPROC_SET, + .p_encode = rpcb_enc_getaddr, + .p_decode = 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 = rpcb_enc_getaddr, + .p_decode = 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 = rpcb_enc_getaddr, + .p_decode = 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 rpc_procinfo rpcb_procedures4[] = { + [RPCBPROC_SET] = { + .p_proc = RPCBPROC_SET, + .p_encode = rpcb_enc_getaddr, + .p_decode = 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 = rpcb_enc_getaddr, + .p_decode = 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 = rpcb_enc_getaddr, + .p_decode = 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 unsigned int rpcb_version2_counts[ARRAY_SIZE(rpcb_procedures2)]; +static const struct rpc_version rpcb_version2 = { + .number = RPCBVERS_2, + .nrprocs = ARRAY_SIZE(rpcb_procedures2), + .procs = rpcb_procedures2, + .counts = rpcb_version2_counts, +}; + +static unsigned int rpcb_version3_counts[ARRAY_SIZE(rpcb_procedures3)]; +static const struct rpc_version rpcb_version3 = { + .number = RPCBVERS_3, + .nrprocs = ARRAY_SIZE(rpcb_procedures3), + .procs = rpcb_procedures3, + .counts = rpcb_version3_counts, +}; + +static unsigned int rpcb_version4_counts[ARRAY_SIZE(rpcb_procedures4)]; +static const struct rpc_version rpcb_version4 = { + .number = RPCBVERS_4, + .nrprocs = ARRAY_SIZE(rpcb_procedures4), + .procs = rpcb_procedures4, + .counts = rpcb_version4_counts, +}; + +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, +}; |