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);
  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         spin_lock(&pmap_lock);
  57         if (map->pm_binding) {
  58                 rpc_sleep_on(&map->pm_bindwait, task, NULL, NULL);
  59                 spin_unlock(&pmap_lock);
  60                 return;
  61         }
  62         map->pm_binding = 1;
  63         spin_unlock(&pmap_lock);
  64
  65         pmap_clnt = pmap_create(clnt->cl_server, sap, map->pm_prot);
  66         if (IS_ERR(pmap_clnt)) {
  67                 task->tk_status = PTR_ERR(pmap_clnt);
  68                 goto bailout;
  69         }
  70         task->tk_status = 0;
  71
  72         /*
  73          * Note: rpc_new_child will release client after a failure.
  74          */
  75         if (!(child = rpc_new_child(pmap_clnt, task)))
  76                 goto bailout;
  77
  78         /* Setup the call info struct */
  79         rpc_call_setup(child, &msg, 0);
  80
  81         /* ... and run the child task */
  82         rpc_run_child(task, child, pmap_getport_done);
  83         return;
  84
  85 bailout:
  86         spin_lock(&pmap_lock);
  87         map->pm_binding = 0;
  88         rpc_wake_up(&map->pm_bindwait);
  89         spin_unlock(&pmap_lock);
  90         task->tk_status = -EIO;
  91         task->tk_action = NULL;
  92 }
  93
  94 #ifdef CONFIG_ROOT_NFS
  95 int
  96 rpc_getport_external(struct sockaddr_in *sin, __u32 prog, __u32 vers, int prot)
  97 {
  98         struct rpc_portmap map = {
  99                 .pm_prog        = prog,
 100                 .pm_vers        = vers,
 101                 .pm_prot        = prot,
 102                 .pm_port        = 0
 103         };
 104         struct rpc_clnt *pmap_clnt;
 105         char            hostname[32];
 106         int             status;
 107
 108         dprintk("RPC:      rpc_getport_external(%u.%u.%u.%u, %d, %d, %d)\n",
 109                         NIPQUAD(sin->sin_addr.s_addr), prog, vers, prot);
 110
 111         sprintf(hostname, "%u.%u.%u.%u", NIPQUAD(sin->sin_addr.s_addr));
 112         pmap_clnt = pmap_create(hostname, sin, prot);
 113         if (IS_ERR(pmap_clnt))
 114                 return PTR_ERR(pmap_clnt);
 115
 116         /* Setup the call info struct */
 117         status = rpc_call(pmap_clnt, PMAP_GETPORT, &map, &map.pm_port, 0);
 118
 119         if (status >= 0) {
 120                 if (map.pm_port != 0)
 121                         return map.pm_port;
 122                 status = -EACCES;
 123         }
 124         return status;
 125 }
 126 #endif
 127
 128 static void
 129 pmap_getport_done(struct rpc_task *task)
 130 {
 131         struct rpc_clnt *clnt = task->tk_client;
 132         struct rpc_portmap *map = clnt->cl_pmap;
 133
 134         dprintk("RPC: %4d pmap_getport_done(status %d, port %d)\n",
 135                         task->tk_pid, task->tk_status, clnt->cl_port);
 136         if (task->tk_status < 0) {
 137                 /* Make the calling task exit with an error */
 138                 task->tk_action = NULL;
 139         } else if (clnt->cl_port == 0) {
 140                 /* Program not registered */
 141                 task->tk_status = -EACCES;
 142                 task->tk_action = NULL;
 143         } else {
 144                 /* byte-swap port number first */
 145                 clnt->cl_port = htons(clnt->cl_port);
 146                 clnt->cl_xprt->addr.sin_port = clnt->cl_port;
 147         }
 148         spin_lock(&pmap_lock);
 149         map->pm_binding = 0;
 150         rpc_wake_up(&map->pm_bindwait);
 151         spin_unlock(&pmap_lock);
 152 }
 153
 154 /*
 155  * Set or unset a port registration with the local portmapper.
 156  * port == 0 means unregister, port != 0 means register.
 157  */
 158 int
 159 rpc_register(u32 prog, u32 vers, int prot, unsigned short port, int *okay)
 160 {
 161         struct sockaddr_in      sin;
 162         struct rpc_portmap      map;
 163         struct rpc_clnt         *pmap_clnt;
 164         int error = 0;
 165
 166         dprintk("RPC: registering (%d, %d, %d, %d) with portmapper.\n",
 167                         prog, vers, prot, port);
 168
 169         sin.sin_family = AF_INET;
 170         sin.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
 171         pmap_clnt = pmap_create("localhost", &sin, IPPROTO_UDP);
 172         if (IS_ERR(pmap_clnt)) {
 173                 error = PTR_ERR(pmap_clnt);
 174                 dprintk("RPC: couldn't create pmap client. Error = %d\n", error);
 175                 return error;
 176         }
 177
 178         map.pm_prog = prog;
 179         map.pm_vers = vers;
 180         map.pm_prot = prot;
 181         map.pm_port = port;
 182
 183         error = rpc_call(pmap_clnt, port? PMAP_SET : PMAP_UNSET,
 184                                         &map, okay, 0);
 185
 186         if (error < 0) {
 187                 printk(KERN_WARNING
 188                         "RPC: failed to contact portmap (errno %d).\n",
 189                         error);
 190         }
 191         dprintk("RPC: registration status %d/%d\n", error, *okay);
 192
 193         /* Client deleted automatically because cl_oneshot == 1 */
 194         return error;
 195 }
 196
 197 static struct rpc_clnt *
 198 pmap_create(char *hostname, struct sockaddr_in *srvaddr, int proto)
 199 {
 200         struct rpc_xprt *xprt;
 201         struct rpc_clnt *clnt;
 202
 203         /* printk("pmap: create xprt\n"); */
 204         xprt = xprt_create_proto(proto, srvaddr, NULL);
 205         if (IS_ERR(xprt))
 206                 return (struct rpc_clnt *)xprt;
 207         xprt->addr.sin_port = htons(RPC_PMAP_PORT);
 208
 209         /* printk("pmap: create clnt\n"); */
 210         clnt = rpc_create_client(xprt, hostname,
 211                                 &pmap_program, RPC_PMAP_VERSION,
 212                                 RPC_AUTH_UNIX);
 213         if (IS_ERR(clnt)) {
 214                 xprt_destroy(xprt);
 215         } else {
 216                 clnt->cl_softrtry = 1;
 217                 clnt->cl_chatty   = 1;
 218                 clnt->cl_oneshot  = 1;
 219         }
 220         return clnt;
 221 }
 222
 223 /*
 224  * XDR encode/decode functions for PMAP
 225  */
 226 static int
 227 xdr_encode_mapping(struct rpc_rqst *req, u32 *p, struct rpc_portmap *map)
 228 {
 229         dprintk("RPC: xdr_encode_mapping(%d, %d, %d, %d)\n",
 230                 map->pm_prog, map->pm_vers, map->pm_prot, map->pm_port);
 231         *p++ = htonl(map->pm_prog);
 232         *p++ = htonl(map->pm_vers);
 233         *p++ = htonl(map->pm_prot);
 234         *p++ = htonl(map->pm_port);
 235
 236         req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
 237         return 0;
 238 }
 239
 240 static int
 241 xdr_decode_port(struct rpc_rqst *req, u32 *p, unsigned short *portp)
 242 {
 243         *portp = (unsigned short) ntohl(*p++);
 244         return 0;
 245 }
 246
 247 static int
 248 xdr_decode_bool(struct rpc_rqst *req, u32 *p, unsigned int *boolp)
 249 {
 250         *boolp = (unsigned int) ntohl(*p++);
 251         return 0;
 252 }
 253
 254 static struct rpc_procinfo      pmap_procedures[] = {
 255 [PMAP_SET] = {
 256           .p_proc               = PMAP_SET,
 257           .p_encode             = (kxdrproc_t) xdr_encode_mapping,
 258           .p_decode             = (kxdrproc_t) xdr_decode_bool,
 259           .p_bufsiz             = 4,
 260           .p_count              = 1,
 261         },
 262 [PMAP_UNSET] = {
 263           .p_proc               = PMAP_UNSET,
 264           .p_encode             = (kxdrproc_t) xdr_encode_mapping,
 265           .p_decode             = (kxdrproc_t) xdr_decode_bool,
 266           .p_bufsiz             = 4,
 267           .p_count              = 1,
 268         },
 269 [PMAP_GETPORT] = {
 270           .p_proc               = PMAP_GETPORT,
 271           .p_encode             = (kxdrproc_t) xdr_encode_mapping,
 272           .p_decode             = (kxdrproc_t) xdr_decode_port,
 273           .p_bufsiz             = 4,
 274           .p_count              = 1,
 275         },
 276 };
 277
 278 static struct rpc_version       pmap_version2 = {
 279         .number         = 2,
 280         .nrprocs        = 4,
 281         .procs          = pmap_procedures
 282 };
 283
 284 static struct rpc_version *     pmap_version[] = {
 285         NULL,
 286         NULL,
 287         &pmap_version2
 288 };
 289
 290 static struct rpc_stat          pmap_stats;
 291
 292 static struct rpc_program       pmap_program = {
 293         .name           = "portmap",
 294         .number         = RPC_PMAP_PROGRAM,
 295         .nrvers         = ARRAY_SIZE(pmap_version),
 296         .version        = pmap_version,
 297         .stats          = &pmap_stats,
 298 };