net/sunrpc/pmap_clnt.c

   1 /*
   2  * linux/net/sunrpc/pmap.c
   3  *
   4  * Portmapper client.
   5  *
   6  * Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de>
   7  */
   8
   9 #include <linux/config.h>
  10 #include <linux/types.h>
  11 #include <linux/socket.h>
  12 #include <linux/kernel.h>
  13 #include <linux/errno.h>
  14 #include <linux/uio.h>
  15 #include <linux/in.h>
  16 #include <linux/sunrpc/clnt.h>
  17 #include <linux/sunrpc/xprt.h>
  18 #include <linux/sunrpc/sched.h>
  19
  20 #ifdef RPC_DEBUG
  21 # define RPCDBG_FACILITY        RPCDBG_PMAP
  22 #endif
  23
  24 #define PMAP_SET                1
  25 #define PMAP_UNSET              2
  26 #define PMAP_GETPORT            3
  27
  28 static struct rpc_procinfo      pmap_procedures[];
  29 static struct rpc_clnt *        pmap_create(char *, struct sockaddr_in *, int, int);
  30 static void                     pmap_getport_done(struct rpc_task *);
  31 static struct rpc_program       pmap_program;
  32 static DEFINE_SPINLOCK(pmap_lock);
  33
  34 /*
  35  * Obtain the port for a given RPC service on a given host. This one can
  36  * be called for an ongoing RPC request.
  37  */
  38 void
  39 rpc_getport(struct rpc_task *task, struct rpc_clnt *clnt)
  40 {
  41         struct rpc_portmap *map = clnt->cl_pmap;
  42         struct sockaddr_in *sap = &clnt->cl_xprt->addr;
  43         struct rpc_message msg = {
  44                 .rpc_proc       = &pmap_procedures[PMAP_GETPORT],
  45                 .rpc_argp       = map,
  46                 .rpc_resp       = &clnt->cl_port,
  47                 .rpc_cred       = NULL
  48         };
  49         struct rpc_clnt *pmap_clnt;
  50         struct rpc_task *child;
  51
  52         dprintk("RPC: %4d rpc_getport(%s, %d, %d, %d)\n",
  53                         task->tk_pid, clnt->cl_server,
  54                         map->pm_prog, map->pm_vers, map->pm_prot);
  55
  56         /* Autobind on cloned rpc clients is discouraged */
  57         BUG_ON(clnt->cl_parent != clnt);
  58
  59         spin_lock(&pmap_lock);
  60         if (map->pm_binding) {
  61                 rpc_sleep_on(&map->pm_bindwait, task, NULL, NULL);
  62                 spin_unlock(&pmap_lock);
  63                 return;
  64         }
  65         map->pm_binding = 1;
  66         spin_unlock(&pmap_lock);
  67
  68         pmap_clnt = pmap_create(clnt->cl_server, sap, map->pm_prot, 0);
  69         if (IS_ERR(pmap_clnt)) {
  70                 task->tk_status = PTR_ERR(pmap_clnt);
  71                 goto bailout;
  72         }
  73         task->tk_status = 0;
  74
  75         /*
  76          * Note: rpc_new_child will release client after a failure.
  77          */
  78         if (!(child = rpc_new_child(pmap_clnt, task)))
  79                 goto bailout;
  80
  81         /* Setup the call info struct */
  82         rpc_call_setup(child, &msg, 0);
  83
  84         /* ... and run the child task */
  85         task->tk_xprt->stat.bind_count++;
  86         rpc_run_child(task, child, pmap_getport_done);
  87         return;
  88
  89 bailout:
  90         spin_lock(&pmap_lock);
  91         map->pm_binding = 0;
  92         rpc_wake_up(&map->pm_bindwait);
  93         spin_unlock(&pmap_lock);
  94         rpc_exit(task, -EIO);
  95 }
  96
  97 #ifdef CONFIG_ROOT_NFS
  98 int
  99 rpc_getport_external(struct sockaddr_in *sin, __u32 prog, __u32 vers, int prot)
 100 {
 101         struct rpc_portmap map = {
 102                 .pm_prog        = prog,
 103                 .pm_vers        = vers,
 104                 .pm_prot        = prot,
 105                 .pm_port        = 0
 106         };
 107         struct rpc_message msg = {
 108                 .rpc_proc       = &pmap_procedures[PMAP_GETPORT],
 109                 .rpc_argp       = &map,
 110                 .rpc_resp       = &map.pm_port,
 111         };
 112         struct rpc_clnt *pmap_clnt;
 113         char            hostname[32];
 114         int             status;
 115
 116         dprintk("RPC:      rpc_getport_external(%u.%u.%u.%u, %d, %d, %d)\n",
 117                         NIPQUAD(sin->sin_addr.s_addr), prog, vers, prot);
 118
 119         sprintf(hostname, "%u.%u.%u.%u", NIPQUAD(sin->sin_addr.s_addr));
 120         pmap_clnt = pmap_create(hostname, sin, prot, 0);
 121         if (IS_ERR(pmap_clnt))
 122                 return PTR_ERR(pmap_clnt);
 123
 124         /* Setup the call info struct */
 125         status = rpc_call_sync(pmap_clnt, &msg, 0);
 126
 127         if (status >= 0) {
 128                 if (map.pm_port != 0)
 129                         return map.pm_port;
 130                 status = -EACCES;
 131         }
 132         return status;
 133 }
 134 #endif
 135
 136 static void
 137 pmap_getport_done(struct rpc_task *task)
 138 {
 139         struct rpc_clnt *clnt = task->tk_client;
 140         struct rpc_xprt *xprt = task->tk_xprt;
 141         struct rpc_portmap *map = clnt->cl_pmap;
 142
 143         dprintk("RPC: %4d pmap_getport_done(status %d, port %d)\n",
 144                         task->tk_pid, task->tk_status, clnt->cl_port);
 145
 146         xprt->ops->set_port(xprt, 0);
 147         if (task->tk_status < 0) {
 148                 /* Make the calling task exit with an error */
 149                 task->tk_action = rpc_exit_task;
 150         } else if (clnt->cl_port == 0) {
 151                 /* Program not registered */
 152                 rpc_exit(task, -EACCES);
 153         } else {
 154                 xprt->ops->set_port(xprt, clnt->cl_port);
 155                 clnt->cl_port = htons(clnt->cl_port);
 156         }
 157         spin_lock(&pmap_lock);
 158         map->pm_binding = 0;
 159         rpc_wake_up(&map->pm_bindwait);
 160         spin_unlock(&pmap_lock);
 161 }
 162
 163 /*
 164  * Set or unset a port registration with the local portmapper.
 165  * port == 0 means unregister, port != 0 means register.
 166  */
 167 int
 168 rpc_register(u32 prog, u32 vers, int prot, unsigned short port, int *okay)
 169 {
 170         struct sockaddr_in      sin = {
 171                 .sin_family     = AF_INET,
 172                 .sin_addr.s_addr = htonl(INADDR_LOOPBACK),
 173         };
 174         struct rpc_portmap      map = {
 175                 .pm_prog        = prog,
 176                 .pm_vers        = vers,
 177                 .pm_prot        = prot,
 178                 .pm_port        = port,
 179         };
 180         struct rpc_message msg = {
 181                 .rpc_proc       = &pmap_procedures[port ? PMAP_SET : PMAP_UNSET],
 182                 .rpc_argp       = &map,
 183                 .rpc_resp       = okay,
 184         };
 185         struct rpc_clnt         *pmap_clnt;
 186         int error = 0;
 187
 188         dprintk("RPC: registering (%d, %d, %d, %d) with portmapper.\n",
 189                         prog, vers, prot, port);
 190
 191         pmap_clnt = pmap_create("localhost", &sin, IPPROTO_UDP, 1);
 192         if (IS_ERR(pmap_clnt)) {
 193                 error = PTR_ERR(pmap_clnt);
 194                 dprintk("RPC: couldn't create pmap client. Error = %d\n", error);
 195                 return error;
 196         }
 197
 198         error = rpc_call_sync(pmap_clnt, &msg, 0);
 199
 200         if (error < 0) {
 201                 printk(KERN_WARNING
 202                         "RPC: failed to contact portmap (errno %d).\n",
 203                         error);
 204         }
 205         dprintk("RPC: registration status %d/%d\n", error, *okay);
 206
 207         /* Client deleted automatically because cl_oneshot == 1 */
 208         return error;
 209 }
 210
 211 static struct rpc_clnt *
 212 pmap_create(char *hostname, struct sockaddr_in *srvaddr, int proto, int privileged)
 213 {
 214         struct rpc_xprt *xprt;
 215         struct rpc_clnt *clnt;
 216
 217         /* printk("pmap: create xprt\n"); */
 218         xprt = xprt_create_proto(proto, srvaddr, NULL);
 219         if (IS_ERR(xprt))
 220                 return (struct rpc_clnt *)xprt;
 221         xprt->ops->set_port(xprt, RPC_PMAP_PORT);
 222         if (!privileged)
 223                 xprt->resvport = 0;
 224
 225         /* printk("pmap: create clnt\n"); */
 226         clnt = rpc_new_client(xprt, hostname,
 227                                 &pmap_program, RPC_PMAP_VERSION,
 228                                 RPC_AUTH_UNIX);
 229         if (!IS_ERR(clnt)) {
 230                 clnt->cl_softrtry = 1;
 231                 clnt->cl_oneshot  = 1;
 232         }
 233         return clnt;
 234 }
 235
 236 /*
 237  * XDR encode/decode functions for PMAP
 238  */
 239 static int
 240 xdr_encode_mapping(struct rpc_rqst *req, u32 *p, struct rpc_portmap *map)
 241 {
 242         dprintk("RPC: xdr_encode_mapping(%d, %d, %d, %d)\n",
 243                 map->pm_prog, map->pm_vers, map->pm_prot, map->pm_port);
 244         *p++ = htonl(map->pm_prog);
 245         *p++ = htonl(map->pm_vers);
 246         *p++ = htonl(map->pm_prot);
 247         *p++ = htonl(map->pm_port);
 248
 249         req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
 250         return 0;
 251 }
 252
 253 static int
 254 xdr_decode_port(struct rpc_rqst *req, u32 *p, unsigned short *portp)
 255 {
 256         *portp = (unsigned short) ntohl(*p++);
 257         return 0;
 258 }
 259
 260 static int
 261 xdr_decode_bool(struct rpc_rqst *req, u32 *p, unsigned int *boolp)
 262 {
 263         *boolp = (unsigned int) ntohl(*p++);
 264         return 0;
 265 }
 266
 267 static struct rpc_procinfo      pmap_procedures[] = {
 268 [PMAP_SET] = {
 269           .p_proc               = PMAP_SET,
 270           .p_encode             = (kxdrproc_t) xdr_encode_mapping,
 271           .p_decode             = (kxdrproc_t) xdr_decode_bool,
 272           .p_bufsiz             = 4,
 273           .p_count              = 1,
 274           .p_statidx            = PMAP_SET,
 275           .p_name               = "SET",
 276         },
 277 [PMAP_UNSET] = {
 278           .p_proc               = PMAP_UNSET,
 279           .p_encode             = (kxdrproc_t) xdr_encode_mapping,
 280           .p_decode             = (kxdrproc_t) xdr_decode_bool,
 281           .p_bufsiz             = 4,
 282           .p_count              = 1,
 283           .p_statidx            = PMAP_UNSET,
 284           .p_name               = "UNSET",
 285         },
 286 [PMAP_GETPORT] = {
 287           .p_proc               = PMAP_GETPORT,
 288           .p_encode             = (kxdrproc_t) xdr_encode_mapping,
 289           .p_decode             = (kxdrproc_t) xdr_decode_port,
 290           .p_bufsiz             = 4,
 291           .p_count              = 1,
 292           .p_statidx            = PMAP_GETPORT,
 293           .p_name               = "GETPORT",
 294         },
 295 };
 296
 297 static struct rpc_version       pmap_version2 = {
 298         .number         = 2,
 299         .nrprocs        = 4,
 300         .procs          = pmap_procedures
 301 };
 302
 303 static struct rpc_version *     pmap_version[] = {
 304         NULL,
 305         NULL,
 306         &pmap_version2
 307 };
 308
 309 static struct rpc_stat          pmap_stats;
 310
 311 static struct rpc_program       pmap_program = {
 312         .name           = "portmap",
 313         .number         = RPC_PMAP_PROGRAM,
 314         .nrvers         = ARRAY_SIZE(pmap_version),
 315         .version        = pmap_version,
 316         .stats          = &pmap_stats,
 317 };