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         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_clnt *pmap_clnt;
 107         char            hostname[32];
 108         int             status;
 109
 110         dprintk("RPC:      rpc_getport_external(%u.%u.%u.%u, %d, %d, %d)\n",
 111                         NIPQUAD(sin->sin_addr.s_addr), prog, vers, prot);
 112
 113         sprintf(hostname, "%u.%u.%u.%u", NIPQUAD(sin->sin_addr.s_addr));
 114         pmap_clnt = pmap_create(hostname, sin, prot, 0);
 115         if (IS_ERR(pmap_clnt))
 116                 return PTR_ERR(pmap_clnt);
 117
 118         /* Setup the call info struct */
 119         status = rpc_call(pmap_clnt, PMAP_GETPORT, &map, &map.pm_port, 0);
 120
 121         if (status >= 0) {
 122                 if (map.pm_port != 0)
 123                         return map.pm_port;
 124                 status = -EACCES;
 125         }
 126         return status;
 127 }
 128 #endif
 129
 130 static void
 131 pmap_getport_done(struct rpc_task *task)
 132 {
 133         struct rpc_clnt *clnt = task->tk_client;
 134         struct rpc_portmap *map = clnt->cl_pmap;
 135
 136         dprintk("RPC: %4d pmap_getport_done(status %d, port %d)\n",
 137                         task->tk_pid, task->tk_status, clnt->cl_port);
 138         if (task->tk_status < 0) {
 139                 /* Make the calling task exit with an error */
 140                 task->tk_action = rpc_exit_task;
 141         } else if (clnt->cl_port == 0) {
 142                 /* Program not registered */
 143                 rpc_exit(task, -EACCES);
 144         } else {
 145                 /* byte-swap port number first */
 146                 clnt->cl_port = htons(clnt->cl_port);
 147                 clnt->cl_xprt->addr.sin_port = clnt->cl_port;
 148         }
 149         spin_lock(&pmap_lock);
 150         map->pm_binding = 0;
 151         rpc_wake_up(&map->pm_bindwait);
 152         spin_unlock(&pmap_lock);
 153 }
 154
 155 /*
 156  * Set or unset a port registration with the local portmapper.
 157  * port == 0 means unregister, port != 0 means register.
 158  */
 159 int
 160 rpc_register(u32 prog, u32 vers, int prot, unsigned short port, int *okay)
 161 {
 162         struct sockaddr_in      sin;
 163         struct rpc_portmap      map;
 164         struct rpc_clnt         *pmap_clnt;
 165         int error = 0;
 166
 167         dprintk("RPC: registering (%d, %d, %d, %d) with portmapper.\n",
 168                         prog, vers, prot, port);
 169
 170         sin.sin_family = AF_INET;
 171         sin.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
 172         pmap_clnt = pmap_create("localhost", &sin, IPPROTO_UDP, 1);
 173         if (IS_ERR(pmap_clnt)) {
 174                 error = PTR_ERR(pmap_clnt);
 175                 dprintk("RPC: couldn't create pmap client. Error = %d\n", error);
 176                 return error;
 177         }
 178
 179         map.pm_prog = prog;
 180         map.pm_vers = vers;
 181         map.pm_prot = prot;
 182         map.pm_port = port;
 183
 184         error = rpc_call(pmap_clnt, port? PMAP_SET : PMAP_UNSET,
 185                                         &map, okay, 0);
 186
 187         if (error < 0) {
 188                 printk(KERN_WARNING
 189                         "RPC: failed to contact portmap (errno %d).\n",
 190                         error);
 191         }
 192         dprintk("RPC: registration status %d/%d\n", error, *okay);
 193
 194         /* Client deleted automatically because cl_oneshot == 1 */
 195         return error;
 196 }
 197
 198 static struct rpc_clnt *
 199 pmap_create(char *hostname, struct sockaddr_in *srvaddr, int proto, int privileged)
 200 {
 201         struct rpc_xprt *xprt;
 202         struct rpc_clnt *clnt;
 203
 204         /* printk("pmap: create xprt\n"); */
 205         xprt = xprt_create_proto(proto, srvaddr, NULL);
 206         if (IS_ERR(xprt))
 207                 return (struct rpc_clnt *)xprt;
 208         xprt->addr.sin_port = htons(RPC_PMAP_PORT);
 209         if (!privileged)
 210                 xprt->resvport = 0;
 211
 212         /* printk("pmap: create clnt\n"); */
 213         clnt = rpc_new_client(xprt, hostname,
 214                                 &pmap_program, RPC_PMAP_VERSION,
 215                                 RPC_AUTH_UNIX);
 216         if (!IS_ERR(clnt)) {
 217                 clnt->cl_softrtry = 1;
 218                 clnt->cl_chatty   = 1;
 219                 clnt->cl_oneshot  = 1;
 220         }
 221         return clnt;
 222 }
 223
 224 /*
 225  * XDR encode/decode functions for PMAP
 226  */
 227 static int
 228 xdr_encode_mapping(struct rpc_rqst *req, u32 *p, struct rpc_portmap *map)
 229 {
 230         dprintk("RPC: xdr_encode_mapping(%d, %d, %d, %d)\n",
 231                 map->pm_prog, map->pm_vers, map->pm_prot, map->pm_port);
 232         *p++ = htonl(map->pm_prog);
 233         *p++ = htonl(map->pm_vers);
 234         *p++ = htonl(map->pm_prot);
 235         *p++ = htonl(map->pm_port);
 236
 237         req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
 238         return 0;
 239 }
 240
 241 static int
 242 xdr_decode_port(struct rpc_rqst *req, u32 *p, unsigned short *portp)
 243 {
 244         *portp = (unsigned short) ntohl(*p++);
 245         return 0;
 246 }
 247
 248 static int
 249 xdr_decode_bool(struct rpc_rqst *req, u32 *p, unsigned int *boolp)
 250 {
 251         *boolp = (unsigned int) ntohl(*p++);
 252         return 0;
 253 }
 254
 255 static struct rpc_procinfo      pmap_procedures[] = {
 256 [PMAP_SET] = {
 257           .p_proc               = PMAP_SET,
 258           .p_encode             = (kxdrproc_t) xdr_encode_mapping,
 259           .p_decode             = (kxdrproc_t) xdr_decode_bool,
 260           .p_bufsiz             = 4,
 261           .p_count              = 1,
 262         },
 263 [PMAP_UNSET] = {
 264           .p_proc               = PMAP_UNSET,
 265           .p_encode             = (kxdrproc_t) xdr_encode_mapping,
 266           .p_decode             = (kxdrproc_t) xdr_decode_bool,
 267           .p_bufsiz             = 4,
 268           .p_count              = 1,
 269         },
 270 [PMAP_GETPORT] = {
 271           .p_proc               = PMAP_GETPORT,
 272           .p_encode             = (kxdrproc_t) xdr_encode_mapping,
 273           .p_decode             = (kxdrproc_t) xdr_decode_port,
 274           .p_bufsiz             = 4,
 275           .p_count              = 1,
 276         },
 277 };
 278
 279 static struct rpc_version       pmap_version2 = {
 280         .number         = 2,
 281         .nrprocs        = 4,
 282         .procs          = pmap_procedures
 283 };
 284
 285 static struct rpc_version *     pmap_version[] = {
 286         NULL,
 287         NULL,
 288         &pmap_version2
 289 };
 290
 291 static struct rpc_stat          pmap_stats;
 292
 293 static struct rpc_program       pmap_program = {
 294         .name           = "portmap",
 295         .number         = RPC_PMAP_PROGRAM,
 296         .nrvers         = ARRAY_SIZE(pmap_version),
 297         .version        = pmap_version,
 298         .stats          = &pmap_stats,
 299 };