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_clnt *pmap_clnt;
 108         char            hostname[32];
 109         int             status;
 110
 111         dprintk("RPC:      rpc_getport_external(%u.%u.%u.%u, %d, %d, %d)\n",
 112                         NIPQUAD(sin->sin_addr.s_addr), prog, vers, prot);
 113
 114         sprintf(hostname, "%u.%u.%u.%u", NIPQUAD(sin->sin_addr.s_addr));
 115         pmap_clnt = pmap_create(hostname, sin, prot, 0);
 116         if (IS_ERR(pmap_clnt))
 117                 return PTR_ERR(pmap_clnt);
 118
 119         /* Setup the call info struct */
 120         status = rpc_call(pmap_clnt, PMAP_GETPORT, &map, &map.pm_port, 0);
 121
 122         if (status >= 0) {
 123                 if (map.pm_port != 0)
 124                         return map.pm_port;
 125                 status = -EACCES;
 126         }
 127         return status;
 128 }
 129 #endif
 130
 131 static void
 132 pmap_getport_done(struct rpc_task *task)
 133 {
 134         struct rpc_clnt *clnt = task->tk_client;
 135         struct rpc_xprt *xprt = task->tk_xprt;
 136         struct rpc_portmap *map = clnt->cl_pmap;
 137
 138         dprintk("RPC: %4d pmap_getport_done(status %d, port %d)\n",
 139                         task->tk_pid, task->tk_status, clnt->cl_port);
 140
 141         xprt->ops->set_port(xprt, 0);
 142         if (task->tk_status < 0) {
 143                 /* Make the calling task exit with an error */
 144                 task->tk_action = rpc_exit_task;
 145         } else if (clnt->cl_port == 0) {
 146                 /* Program not registered */
 147                 rpc_exit(task, -EACCES);
 148         } else {
 149                 xprt->ops->set_port(xprt, clnt->cl_port);
 150                 clnt->cl_port = htons(clnt->cl_port);
 151         }
 152         spin_lock(&pmap_lock);
 153         map->pm_binding = 0;
 154         rpc_wake_up(&map->pm_bindwait);
 155         spin_unlock(&pmap_lock);
 156 }
 157
 158 /*
 159  * Set or unset a port registration with the local portmapper.
 160  * port == 0 means unregister, port != 0 means register.
 161  */
 162 int
 163 rpc_register(u32 prog, u32 vers, int prot, unsigned short port, int *okay)
 164 {
 165         struct sockaddr_in      sin;
 166         struct rpc_portmap      map;
 167         struct rpc_clnt         *pmap_clnt;
 168         int error = 0;
 169
 170         dprintk("RPC: registering (%d, %d, %d, %d) with portmapper.\n",
 171                         prog, vers, prot, port);
 172
 173         sin.sin_family = AF_INET;
 174         sin.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
 175         pmap_clnt = pmap_create("localhost", &sin, IPPROTO_UDP, 1);
 176         if (IS_ERR(pmap_clnt)) {
 177                 error = PTR_ERR(pmap_clnt);
 178                 dprintk("RPC: couldn't create pmap client. Error = %d\n", error);
 179                 return error;
 180         }
 181
 182         map.pm_prog = prog;
 183         map.pm_vers = vers;
 184         map.pm_prot = prot;
 185         map.pm_port = port;
 186
 187         error = rpc_call(pmap_clnt, port? PMAP_SET : PMAP_UNSET,
 188                                         &map, okay, 0);
 189
 190         if (error < 0) {
 191                 printk(KERN_WARNING
 192                         "RPC: failed to contact portmap (errno %d).\n",
 193                         error);
 194         }
 195         dprintk("RPC: registration status %d/%d\n", error, *okay);
 196
 197         /* Client deleted automatically because cl_oneshot == 1 */
 198         return error;
 199 }
 200
 201 static struct rpc_clnt *
 202 pmap_create(char *hostname, struct sockaddr_in *srvaddr, int proto, int privileged)
 203 {
 204         struct rpc_xprt *xprt;
 205         struct rpc_clnt *clnt;
 206
 207         /* printk("pmap: create xprt\n"); */
 208         xprt = xprt_create_proto(proto, srvaddr, NULL);
 209         if (IS_ERR(xprt))
 210                 return (struct rpc_clnt *)xprt;
 211         xprt->ops->set_port(xprt, RPC_PMAP_PORT);
 212         if (!privileged)
 213                 xprt->resvport = 0;
 214
 215         /* printk("pmap: create clnt\n"); */
 216         clnt = rpc_new_client(xprt, hostname,
 217                                 &pmap_program, RPC_PMAP_VERSION,
 218                                 RPC_AUTH_UNIX);
 219         if (!IS_ERR(clnt)) {
 220                 clnt->cl_softrtry = 1;
 221                 clnt->cl_oneshot  = 1;
 222         }
 223         return clnt;
 224 }
 225
 226 /*
 227  * XDR encode/decode functions for PMAP
 228  */
 229 static int
 230 xdr_encode_mapping(struct rpc_rqst *req, u32 *p, struct rpc_portmap *map)
 231 {
 232         dprintk("RPC: xdr_encode_mapping(%d, %d, %d, %d)\n",
 233                 map->pm_prog, map->pm_vers, map->pm_prot, map->pm_port);
 234         *p++ = htonl(map->pm_prog);
 235         *p++ = htonl(map->pm_vers);
 236         *p++ = htonl(map->pm_prot);
 237         *p++ = htonl(map->pm_port);
 238
 239         req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
 240         return 0;
 241 }
 242
 243 static int
 244 xdr_decode_port(struct rpc_rqst *req, u32 *p, unsigned short *portp)
 245 {
 246         *portp = (unsigned short) ntohl(*p++);
 247         return 0;
 248 }
 249
 250 static int
 251 xdr_decode_bool(struct rpc_rqst *req, u32 *p, unsigned int *boolp)
 252 {
 253         *boolp = (unsigned int) ntohl(*p++);
 254         return 0;
 255 }
 256
 257 static struct rpc_procinfo      pmap_procedures[] = {
 258 [PMAP_SET] = {
 259           .p_proc               = PMAP_SET,
 260           .p_encode             = (kxdrproc_t) xdr_encode_mapping,
 261           .p_decode             = (kxdrproc_t) xdr_decode_bool,
 262           .p_bufsiz             = 4,
 263           .p_count              = 1,
 264           .p_statidx            = PMAP_SET,
 265           .p_name               = "SET",
 266         },
 267 [PMAP_UNSET] = {
 268           .p_proc               = PMAP_UNSET,
 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_UNSET,
 274           .p_name               = "UNSET",
 275         },
 276 [PMAP_GETPORT] = {
 277           .p_proc               = PMAP_GETPORT,
 278           .p_encode             = (kxdrproc_t) xdr_encode_mapping,
 279           .p_decode             = (kxdrproc_t) xdr_decode_port,
 280           .p_bufsiz             = 4,
 281           .p_count              = 1,
 282           .p_statidx            = PMAP_GETPORT,
 283           .p_name               = "GETPORT",
 284         },
 285 };
 286
 287 static struct rpc_version       pmap_version2 = {
 288         .number         = 2,
 289         .nrprocs        = 4,
 290         .procs          = pmap_procedures
 291 };
 292
 293 static struct rpc_version *     pmap_version[] = {
 294         NULL,
 295         NULL,
 296         &pmap_version2
 297 };
 298
 299 static struct rpc_stat          pmap_stats;
 300
 301 static struct rpc_program       pmap_program = {
 302         .name           = "portmap",
 303         .number         = RPC_PMAP_PROGRAM,
 304         .nrvers         = ARRAY_SIZE(pmap_version),
 305         .version        = pmap_version,
 306         .stats          = &pmap_stats,
 307 };