net/sunrpc/pmap_clnt.c

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