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