1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21 /*
  22  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
  23  * Use is subject to license terms.
  24  */
  25 
  26 /*      Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T */
  27 /*        All Rights Reserved   */
  28 
  29 /*
  30  * Portions of this source code were derived from Berkeley 4.3 BSD
  31  * under license from the Regents of the University of California.
  32  */
  33 
  34 /*
  35  * This module provides the user level support for the NFSv4
  36  * callback program.  It is modeled after nfsd.  When a nfsv4
  37  * mount occurs, the mount command forks and the child runs
  38  * start_nfs4_callback.  If this is the first mount, then the
  39  * process will hang around listening for incoming connection
  40  * requests from the nfsv4 server.
  41  *
  42  * For connection-less protocols, the krpc is started immediately.
  43  * For connection oriented protocols, the kernel module is informed
  44  * of netid and universal address that it can give this
  45  * information to the server during setclientid.
  46  */
  47 
  48 #include <sys/param.h>
  49 #include <sys/types.h>
  50 #include <syslog.h>
  51 #include <tiuser.h>
  52 #include <rpc/rpc.h>
  53 #include <errno.h>
  54 #include <thread.h>
  55 #include <sys/resource.h>
  56 #include <sys/file.h>
  57 #include <nfs/nfs.h>
  58 #include <nfs/nfssys.h>
  59 #include <stdio.h>
  60 #include <stdlib.h>
  61 #include <netconfig.h>
  62 #include <netdir.h>
  63 #include <string.h>
  64 #include <unistd.h>
  65 #include <stropts.h>
  66 #include <sys/tihdr.h>
  67 #include <netinet/tcp.h>
  68 #include "nfs_tbind.h"
  69 #include "thrpool.h"
  70 #include <rpcsvc/nfs4_prot.h>
  71 #include <netdb.h>
  72 #include <signal.h>
  73 #include <strings.h>
  74 #include <priv_utils.h>
  75 #include <rpcsvc/daemon_utils.h>
  76 
  77 static  int     nfs4svc(int, struct netbuf *, struct netconfig *, int,
  78                 struct netbuf *);
  79 extern  int     _nfssys(int, void *);
  80 
  81 static  char    *MyName;
  82 
  83 /*
  84  * The following are all globals used by routines in nfs_tbind.c.
  85  */
  86 size_t  end_listen_fds;         /* used by conn_close_oldest() */
  87 size_t  num_fds = 0;            /* used by multiple routines */
  88 int     listen_backlog = 32;    /* used by bind_to_{provider,proto}() */
  89 int     num_servers;            /* used by cots_listen_event() */
  90 int     (*Mysvc)(int, struct netbuf, struct netconfig *) = NULL;
  91                                 /* used by cots_listen_event() */
  92 int     max_conns_allowed = -1; /* used by cots_listen_event() */
  93 
  94 int
  95 main(int argc, char *argv[])
  96 {
  97         int pid;
  98         int i;
  99         struct protob *protobp;
 100         struct flock f;
 101         pid_t pi;
 102         struct svcpool_args cb_svcpool;
 103 
 104         MyName = "nfs4cbd";
 105         Mysvc4 = nfs4svc;
 106 
 107 #ifndef DEBUG
 108         /*
 109          * Close existing file descriptors, open "/dev/null" as
 110          * standard input, output, and error, and detach from
 111          * controlling terminal.
 112          */
 113         closefrom(0);
 114         (void) open("/dev/null", O_RDONLY);
 115         (void) open("/dev/null", O_WRONLY);
 116         (void) dup(1);
 117         (void) setsid();
 118 #endif
 119 
 120         /*
 121          * create a child to continue our work
 122          * Parent's exit will tell mount command we're ready to go
 123          */
 124         if ((pi = fork()) > 0) {
 125                 exit(0);
 126         }
 127 
 128         if (pi == -1) {
 129                 (void) syslog(LOG_ERR,
 130                     "Could not start NFS4_CALLBACK service");
 131                 exit(1);
 132         }
 133 
 134         (void) _create_daemon_lock(NFS4CBD, DAEMON_UID, DAEMON_GID);
 135 
 136         svcsetprio();
 137 
 138         if (__init_daemon_priv(PU_RESETGROUPS|PU_CLEARLIMITSET,
 139             DAEMON_UID, DAEMON_GID, PRIV_SYS_NFS, (char *)NULL) == -1) {
 140                 (void) fprintf(stderr, "%s must be run with sufficient"
 141                     " privileges\n", argv[0]);
 142                 exit(1);
 143         }
 144         /* Basic privileges we don't need, remove from E/P. */
 145         __fini_daemon_priv(PRIV_PROC_EXEC, PRIV_PROC_FORK, PRIV_FILE_LINK_ANY,
 146             PRIV_PROC_SESSION, PRIV_PROC_INFO, (char *)NULL);
 147 
 148         /*
 149          * establish our lock on the lock file and write our pid to it.
 150          * exit if some other process holds the lock, or if there's any
 151          * error in writing/locking the file.
 152          */
 153         pid = _enter_daemon_lock(NFS4CBD);
 154         switch (pid) {
 155         case 0:
 156                 break;
 157         case -1:
 158                 syslog(LOG_ERR, "error locking for %s: %s", NFS4CBD,
 159                     strerror(errno));
 160                 exit(2);
 161         default:
 162                 /* daemon was already running */
 163                 exit(0);
 164         }
 165 
 166         openlog(MyName, LOG_PID | LOG_NDELAY, LOG_DAEMON);
 167 
 168         cb_svcpool.id = NFS_CB_SVCPOOL_ID;
 169         cb_svcpool.maxthreads = 0;
 170         cb_svcpool.redline = 0;
 171         cb_svcpool.qsize = 0;
 172         cb_svcpool.timeout = 0;
 173         cb_svcpool.stksize = 0;
 174         cb_svcpool.max_same_xprt = 0;
 175 
 176         /* create a SVC_POOL for the nfsv4 callback deamon */
 177         if (_nfssys(SVCPOOL_CREATE, &cb_svcpool)) {
 178                 (void) syslog(LOG_ERR, "can't setup NFS_CB SVCPOOL: Exiting");
 179                 exit(1);
 180         }
 181 
 182         /*
 183          * Set up blocked thread to do LWP creation on behalf of the kernel.
 184          */
 185         if (svcwait(NFS_CB_SVCPOOL_ID)) {
 186                 (void) syslog(LOG_ERR,
 187                     "Can't set up NFS_CB LWP creator: Exiting");
 188                 exit(1);
 189         }
 190 
 191 
 192         /*
 193          * Build a protocol block list for registration.
 194          */
 195         protobp = (struct protob *)malloc(sizeof (struct protob));
 196         protobp->serv = "NFS4_CALLBACK";
 197         protobp->versmin = NFS_CB;
 198         protobp->versmax = NFS_CB;
 199         protobp->program = NFS4_CALLBACK;
 200         protobp->next = NULL;
 201 
 202         if (do_all(protobp, NULL, 0) == -1) {
 203                 exit(1);
 204         }
 205 
 206         free(protobp);
 207 
 208         if (num_fds == 0) {
 209                 (void) syslog(LOG_ERR,
 210                 "Could not start NFS4_CALLBACK service for any protocol");
 211                 exit(1);
 212         }
 213 
 214         end_listen_fds = num_fds;
 215         /*
 216          * Poll for non-data control events on the transport descriptors.
 217          */
 218         poll_for_action();
 219 
 220         /*
 221          * If we get here, something failed in poll_for_action().
 222          */
 223         return (1);
 224 }
 225 
 226 char *
 227 get_uaddr(int fd, struct netconfig *nconf, struct netbuf *nb)
 228 {
 229         struct nfs_svc_args nsa;
 230         char *ua, *ua2, *mua = NULL;
 231         char me[MAXHOSTNAMELEN];
 232         struct nd_addrlist *nas;
 233         struct nd_hostserv hs;
 234         struct nd_mergearg ma;
 235 
 236         ua = taddr2uaddr(nconf, nb);
 237 
 238         if (ua == NULL) {
 239 #ifdef  DEBUG
 240                 fprintf(stderr, "taddr2uaddr failed for netid %s\n",
 241                     nconf->nc_netid);
 242 #endif
 243                 return (NULL);
 244         }
 245 
 246         gethostname(me, MAXHOSTNAMELEN);
 247 
 248         hs.h_host = me;
 249         hs.h_serv = "nfs";
 250         if (netdir_getbyname(nconf, &hs, &nas)) {
 251 #ifdef DEBUG
 252                 netdir_perror("netdir_getbyname");
 253 #endif
 254                 return (NULL);
 255         }
 256 
 257         ua2 = taddr2uaddr(nconf, nas->n_addrs);
 258 
 259         if (ua2 == NULL) {
 260 #ifdef  DEBUG
 261                 fprintf(stderr, "taddr2uaddr failed for netid %s.\n",
 262                     nconf->nc_netid);
 263 #endif
 264                 return (NULL);
 265         }
 266 
 267         ma.s_uaddr = ua;
 268         ma.c_uaddr = ua2;
 269         ma.m_uaddr = NULL;
 270 
 271         if (netdir_options(nconf, ND_MERGEADDR, 0, (char *)&ma)) {
 272 #ifdef DEBUG
 273                 netdir_perror("netdir_options");
 274 #endif
 275                 return (NULL);
 276         }
 277 
 278         mua = ma.m_uaddr;
 279         return (mua);
 280 }
 281 
 282 /*
 283  * Establish NFS4 callback service thread.
 284  */
 285 static int
 286 nfs4svc(int fd, struct netbuf *addrmask, struct netconfig *nconf,
 287         int cmd, struct netbuf *addr)
 288 {
 289         struct nfs4_svc_args nsa;
 290         char *ua;
 291         int error;
 292 
 293         ua = get_uaddr(fd, nconf, addr);
 294 
 295         if (ua == NULL) {
 296                 syslog(LOG_NOTICE, "nfsv4 cannot determine local hostname "
 297                     "binding for transport %s - delegations will not be "
 298                     "available on this transport\n", nconf->nc_netid);
 299                 return (0);
 300         }
 301 
 302 #ifdef  DEBUG
 303         if (cmd & NFS4_KRPC_START)
 304                 fprintf(stderr, "nfs4cbd: starting callback rpc on %s %s\n",
 305                     nconf->nc_netid, ua);
 306         else
 307                 fprintf(stderr, "nfs4cbd: listening on %s %s\n",
 308                     nconf->nc_netid, ua);
 309 #endif
 310 
 311         nsa.fd = fd;
 312         nsa.cmd = cmd;
 313         nsa.netid = nconf->nc_netid;
 314         if (addrmask)
 315                 nsa.addrmask = *addrmask;
 316         else
 317                 bzero(&nsa.addrmask, sizeof (struct netbuf));
 318         nsa.addr = ua;
 319         nsa.protofmly = nconf->nc_protofmly;
 320         nsa.proto = nconf->nc_proto;
 321         if ((error = _nfssys(NFS4_SVC, &nsa)) != 0)
 322                 syslog(LOG_ERR, "nfssys NFS4_SVC failed\n");
 323 
 324         return (error);
 325 }