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 2006 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 #pragma ident   "%Z%%M% %I%     %E% SMI"
  35 
  36 /*
  37  * This module provides the user level support for the NFSv4
  38  * callback program.  It is modeled after nfsd.  When a nfsv4
  39  * mount occurs, the mount command forks and the child runs
  40  * start_nfs4_callback.  If this is the first mount, then the
  41  * process will hang around listening for incoming connection
  42  * requests from the nfsv4 server.
  43  *
  44  * For connection-less protocols, the krpc is started immediately.
  45  * For connection oriented protocols, the kernel module is informed
  46  * of netid and universal address that it can give this
  47  * information to the server during setclientid.
  48  */
  49 
  50 #include <sys/param.h>
  51 #include <sys/types.h>
  52 #include <syslog.h>
  53 #include <tiuser.h>
  54 #include <rpc/rpc.h>
  55 #include <errno.h>
  56 #include <thread.h>
  57 #include <sys/resource.h>
  58 #include <sys/file.h>
  59 #include <nfs/nfs.h>
  60 #include <nfs/nfssys.h>
  61 #include <stdio.h>
  62 #include <stdlib.h>
  63 #include <netconfig.h>
  64 #include <netdir.h>
  65 #include <string.h>
  66 #include <unistd.h>
  67 #include <stropts.h>
  68 #include <sys/tihdr.h>
  69 #include <netinet/tcp.h>
  70 #include "nfs_tbind.h"
  71 #include "thrpool.h"
  72 #include <rpcsvc/nfs4_prot.h>
  73 #include <netdb.h>
  74 #include <signal.h>
  75 #include <strings.h>
  76 #include <priv_utils.h>
  77 #include <rpcsvc/daemon_utils.h>
  78 
  79 static  int     nfs4svc(int, struct netbuf *, struct netconfig *, int,
  80                 struct netbuf *);
  81 extern  int     _nfssys(int, void *);
  82 
  83 static  char    *MyName;
  84 
  85 /*
  86  * The following are all globals used by routines in nfs_tbind.c.
  87  */
  88 size_t  end_listen_fds;         /* used by conn_close_oldest() */
  89 size_t  num_fds = 0;            /* used by multiple routines */
  90 int     listen_backlog = 32;    /* used by bind_to_{provider,proto}() */
  91 int     num_servers;            /* used by cots_listen_event() */
  92 int     (*Mysvc)(int, struct netbuf, struct netconfig *) = NULL;
  93                                 /* used by cots_listen_event() */
  94 int     max_conns_allowed = -1; /* used by cots_listen_event() */
  95 
  96 int
  97 main(int argc, char *argv[])
  98 {
  99         int pid;
 100         int i;
 101         struct protob *protobp;
 102         struct flock f;
 103         pid_t pi;
 104         struct svcpool_args cb_svcpool;
 105 
 106         MyName = "nfs4cbd";
 107         Mysvc4 = nfs4svc;
 108 
 109 #ifndef DEBUG
 110         /*
 111          * Close existing file descriptors, open "/dev/null" as
 112          * standard input, output, and error, and detach from
 113          * controlling terminal.
 114          */
 115         closefrom(0);
 116         (void) open("/dev/null", O_RDONLY);
 117         (void) open("/dev/null", O_WRONLY);
 118         (void) dup(1);
 119         (void) setsid();
 120 #endif
 121 
 122         /*
 123          * create a child to continue our work
 124          * Parent's exit will tell mount command we're ready to go
 125          */
 126         if ((pi = fork()) > 0) {
 127                 exit(0);
 128         }
 129 
 130         if (pi == -1) {
 131                 (void) syslog(LOG_ERR,
 132                         "Could not start NFS4_CALLBACK service");
 133                 exit(1);
 134         }
 135 
 136         (void) _create_daemon_lock(NFS4CBD, DAEMON_UID, DAEMON_GID);
 137 
 138         svcsetprio();
 139 
 140         if (__init_daemon_priv(PU_RESETGROUPS|PU_CLEARLIMITSET,
 141             DAEMON_UID, DAEMON_GID, PRIV_SYS_NFS, (char *)NULL) == -1) {
 142                 (void) fprintf(stderr, "%s must be run with sufficient"
 143                         " privileges\n", argv[0]);
 144                 exit(1);
 145         }
 146         /* Basic privileges we don't need, remove from E/P. */
 147         __fini_daemon_priv(PRIV_PROC_EXEC, PRIV_PROC_FORK, PRIV_FILE_LINK_ANY,
 148             PRIV_PROC_SESSION, PRIV_PROC_INFO, (char *)NULL);
 149 
 150         /*
 151          * establish our lock on the lock file and write our pid to it.
 152          * exit if some other process holds the lock, or if there's any
 153          * error in writing/locking the file.
 154          */
 155         pid = _enter_daemon_lock(NFS4CBD);
 156         switch (pid) {
 157         case 0:
 158                 break;
 159         case -1:
 160                 syslog(LOG_ERR, "error locking for %s: %s", NFS4CBD,
 161                     strerror(errno));
 162                 exit(2);
 163         default:
 164                 /* daemon was already running */
 165                 exit(0);
 166         }
 167 
 168         openlog(MyName, LOG_PID | LOG_NDELAY, LOG_DAEMON);
 169 
 170         cb_svcpool.id = NFS_CB_SVCPOOL_ID;
 171         cb_svcpool.maxthreads = 0;
 172         cb_svcpool.redline = 0;
 173         cb_svcpool.qsize = 0;
 174         cb_svcpool.timeout = 0;
 175         cb_svcpool.stksize = 0;
 176         cb_svcpool.max_same_xprt = 0;
 177 
 178         /* create a SVC_POOL for the nfsv4 callback deamon */
 179         if (_nfssys(SVCPOOL_CREATE, &cb_svcpool)) {
 180                 (void) syslog(LOG_ERR, "can't setup NFS_CB SVCPOOL: Exiting");
 181                 exit(1);
 182         }
 183 
 184         /*
 185          * Set up blocked thread to do LWP creation on behalf of the kernel.
 186          */
 187         if (svcwait(NFS_CB_SVCPOOL_ID)) {
 188                 (void) syslog(LOG_ERR,
 189                     "Can't set up NFS_CB LWP creator: Exiting");
 190                 exit(1);
 191         }
 192 
 193 
 194         /*
 195          * Build a protocol block list for registration.
 196          */
 197         protobp = (struct protob *)malloc(sizeof (struct protob));
 198         protobp->serv = "NFS4_CALLBACK";
 199         protobp->versmin = NFS_CB;
 200         protobp->versmax = NFS_CB;
 201         protobp->program = NFS4_CALLBACK;
 202         protobp->next = NULL;
 203 
 204         if (do_all(protobp, NULL, 0) == -1) {
 205                 exit(1);
 206         }
 207 
 208         free(protobp);
 209 
 210         if (num_fds == 0) {
 211                 (void) syslog(LOG_ERR,
 212                 "Could not start NFS4_CALLBACK service for any protocol");
 213                 exit(1);
 214         }
 215 
 216         end_listen_fds = num_fds;
 217         /*
 218          * Poll for non-data control events on the transport descriptors.
 219          */
 220         poll_for_action();
 221 
 222         /*
 223          * If we get here, something failed in poll_for_action().
 224          */
 225         return (1);
 226 }
 227 
 228 char *
 229 get_uaddr(int fd, struct netconfig *nconf, struct netbuf *nb)
 230 {
 231         struct nfs_svc_args nsa;
 232         char *ua, *ua2, *mua = NULL;
 233         char me[MAXHOSTNAMELEN];
 234         struct nd_addrlist *nas;
 235         struct nd_hostserv hs;
 236         struct nd_mergearg ma;
 237 
 238         ua = taddr2uaddr(nconf, nb);
 239 
 240         if (ua == NULL) {
 241 #ifdef  DEBUG
 242                 fprintf(stderr, "taddr2uaddr failed for netid %s\n",
 243                         nconf->nc_netid);
 244 #endif
 245                 return (NULL);
 246         }
 247 
 248         gethostname(me, MAXHOSTNAMELEN);
 249 
 250         hs.h_host = me;
 251         hs.h_serv = "nfs";
 252         if (netdir_getbyname(nconf, &hs, &nas)) {
 253 #ifdef DEBUG
 254                 netdir_perror("netdir_getbyname");
 255 #endif
 256                 return (NULL);
 257         }
 258 
 259         ua2 = taddr2uaddr(nconf, nas->n_addrs);
 260 
 261         if (ua2 == NULL) {
 262 #ifdef  DEBUG
 263                 fprintf(stderr, "taddr2uaddr failed for netid %s.\n",
 264                         nconf->nc_netid);
 265 #endif
 266                 return (NULL);
 267         }
 268 
 269         ma.s_uaddr = ua;
 270         ma.c_uaddr = ua2;
 271         ma.m_uaddr = NULL;
 272 
 273         if (netdir_options(nconf, ND_MERGEADDR, 0, (char *)&ma)) {
 274 #ifdef DEBUG
 275                 netdir_perror("netdir_options");
 276 #endif
 277                 return (NULL);
 278         }
 279 
 280         mua = ma.m_uaddr;
 281         return (mua);
 282 }
 283 
 284 /*
 285  * Establish NFS4 callback service thread.
 286  */
 287 static int
 288 nfs4svc(int fd, struct netbuf *addrmask, struct netconfig *nconf,
 289         int cmd, struct netbuf *addr)
 290 {
 291         struct nfs4_svc_args nsa;
 292         char *ua;
 293         int error;
 294 
 295         ua = get_uaddr(fd, nconf, addr);
 296 
 297         if (ua == NULL) {
 298                 syslog(LOG_NOTICE, "nfsv4 cannot determine local hostname "
 299                         "binding for transport %s - delegations will not be "
 300                         "available on this transport\n", nconf->nc_netid);
 301                 return (0);
 302         }
 303 
 304 #ifdef  DEBUG
 305         if (cmd & NFS4_KRPC_START)
 306                 fprintf(stderr, "nfs4cbd: starting callback rpc on %s %s\n",
 307                         nconf->nc_netid, ua);
 308         else
 309                 fprintf(stderr, "nfs4cbd: listening on %s %s\n",
 310                         nconf->nc_netid, ua);
 311 #endif
 312 
 313         nsa.fd = fd;
 314         nsa.cmd = cmd;
 315         nsa.netid = nconf->nc_netid;
 316         if (addrmask)
 317                 nsa.addrmask = *addrmask;
 318         else
 319                 bzero(&nsa.addrmask, sizeof (struct netbuf));
 320         nsa.addr = ua;
 321         nsa.protofmly = nconf->nc_protofmly;
 322         nsa.proto = nconf->nc_proto;
 323         if ((error = _nfssys(NFS4_SVC, &nsa)) != 0)
 324                 syslog(LOG_ERR, "nfssys NFS4_SVC failed\n");
 325 
 326         return (error);
 327 }